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Commit | Line | Data |
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fc01f7e7 FB |
1 | /* |
2 | * QEMU System Emulator block driver | |
5fafdf24 | 3 | * |
fc01f7e7 | 4 | * Copyright (c) 2003 Fabrice Bellard |
c20555e1 | 5 | * Copyright (c) 2020 Virtuozzo International GmbH. |
5fafdf24 | 6 | * |
fc01f7e7 FB |
7 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
8 | * of this software and associated documentation files (the "Software"), to deal | |
9 | * in the Software without restriction, including without limitation the rights | |
10 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
11 | * copies of the Software, and to permit persons to whom the Software is | |
12 | * furnished to do so, subject to the following conditions: | |
13 | * | |
14 | * The above copyright notice and this permission notice shall be included in | |
15 | * all copies or substantial portions of the Software. | |
16 | * | |
17 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
18 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
19 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
20 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
21 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
22 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
23 | * THE SOFTWARE. | |
24 | */ | |
e688df6b | 25 | |
d38ea87a | 26 | #include "qemu/osdep.h" |
0ab8ed18 | 27 | #include "block/trace.h" |
737e150e PB |
28 | #include "block/block_int.h" |
29 | #include "block/blockjob.h" | |
e2c1c34f | 30 | #include "block/dirty-bitmap.h" |
0c9b70d5 | 31 | #include "block/fuse.h" |
cd7fca95 | 32 | #include "block/nbd.h" |
609f45ea | 33 | #include "block/qdict.h" |
d49b6836 | 34 | #include "qemu/error-report.h" |
5e5733e5 | 35 | #include "block/module_block.h" |
db725815 | 36 | #include "qemu/main-loop.h" |
1de7afc9 | 37 | #include "qemu/module.h" |
e688df6b | 38 | #include "qapi/error.h" |
452fcdbc | 39 | #include "qapi/qmp/qdict.h" |
7b1b5d19 | 40 | #include "qapi/qmp/qjson.h" |
e59a0cf1 | 41 | #include "qapi/qmp/qnull.h" |
fc81fa1e | 42 | #include "qapi/qmp/qstring.h" |
e1d74bc6 KW |
43 | #include "qapi/qobject-output-visitor.h" |
44 | #include "qapi/qapi-visit-block-core.h" | |
bfb197e0 | 45 | #include "sysemu/block-backend.h" |
1de7afc9 | 46 | #include "qemu/notify.h" |
922a01a0 | 47 | #include "qemu/option.h" |
10817bf0 | 48 | #include "qemu/coroutine.h" |
c13163fb | 49 | #include "block/qapi.h" |
1de7afc9 | 50 | #include "qemu/timer.h" |
f348b6d1 VB |
51 | #include "qemu/cutils.h" |
52 | #include "qemu/id.h" | |
0bc329fb HR |
53 | #include "qemu/range.h" |
54 | #include "qemu/rcu.h" | |
21c2283e | 55 | #include "block/coroutines.h" |
fc01f7e7 | 56 | |
71e72a19 | 57 | #ifdef CONFIG_BSD |
7674e7bf | 58 | #include <sys/ioctl.h> |
72cf2d4f | 59 | #include <sys/queue.h> |
feccdcee | 60 | #if defined(HAVE_SYS_DISK_H) |
7674e7bf FB |
61 | #include <sys/disk.h> |
62 | #endif | |
c5e97233 | 63 | #endif |
7674e7bf | 64 | |
49dc768d AL |
65 | #ifdef _WIN32 |
66 | #include <windows.h> | |
67 | #endif | |
68 | ||
1c9805a3 SH |
69 | #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ |
70 | ||
3b491a90 | 71 | /* Protected by BQL */ |
dc364f4c BC |
72 | static QTAILQ_HEAD(, BlockDriverState) graph_bdrv_states = |
73 | QTAILQ_HEAD_INITIALIZER(graph_bdrv_states); | |
74 | ||
3b491a90 | 75 | /* Protected by BQL */ |
2c1d04e0 HR |
76 | static QTAILQ_HEAD(, BlockDriverState) all_bdrv_states = |
77 | QTAILQ_HEAD_INITIALIZER(all_bdrv_states); | |
78 | ||
3b491a90 | 79 | /* Protected by BQL */ |
8a22f02a SH |
80 | static QLIST_HEAD(, BlockDriver) bdrv_drivers = |
81 | QLIST_HEAD_INITIALIZER(bdrv_drivers); | |
ea2384d3 | 82 | |
5b363937 HR |
83 | static BlockDriverState *bdrv_open_inherit(const char *filename, |
84 | const char *reference, | |
85 | QDict *options, int flags, | |
86 | BlockDriverState *parent, | |
bd86fb99 | 87 | const BdrvChildClass *child_class, |
272c02ea | 88 | BdrvChildRole child_role, |
5b363937 | 89 | Error **errp); |
f3930ed0 | 90 | |
bfb8aa6d KW |
91 | static bool bdrv_recurse_has_child(BlockDriverState *bs, |
92 | BlockDriverState *child); | |
93 | ||
ad29eb3d KW |
94 | static void GRAPH_WRLOCK |
95 | bdrv_replace_child_noperm(BdrvChild *child, BlockDriverState *new_bs); | |
96 | ||
2f64e1fc KW |
97 | static void GRAPH_WRLOCK |
98 | bdrv_remove_child(BdrvChild *child, Transaction *tran); | |
0978623e | 99 | |
72373e40 VSO |
100 | static int bdrv_reopen_prepare(BDRVReopenState *reopen_state, |
101 | BlockReopenQueue *queue, | |
ecd30d2d | 102 | Transaction *change_child_tran, Error **errp); |
53e96d1e VSO |
103 | static void bdrv_reopen_commit(BDRVReopenState *reopen_state); |
104 | static void bdrv_reopen_abort(BDRVReopenState *reopen_state); | |
105 | ||
fa8fc1d0 EGE |
106 | static bool bdrv_backing_overridden(BlockDriverState *bs); |
107 | ||
7e8c182f | 108 | static bool bdrv_change_aio_context(BlockDriverState *bs, AioContext *ctx, |
e08cc001 | 109 | GHashTable *visited, Transaction *tran, |
7e8c182f EGE |
110 | Error **errp); |
111 | ||
eb852011 MA |
112 | /* If non-zero, use only whitelisted block drivers */ |
113 | static int use_bdrv_whitelist; | |
114 | ||
9e0b22f4 SH |
115 | #ifdef _WIN32 |
116 | static int is_windows_drive_prefix(const char *filename) | |
117 | { | |
118 | return (((filename[0] >= 'a' && filename[0] <= 'z') || | |
119 | (filename[0] >= 'A' && filename[0] <= 'Z')) && | |
120 | filename[1] == ':'); | |
121 | } | |
122 | ||
123 | int is_windows_drive(const char *filename) | |
124 | { | |
125 | if (is_windows_drive_prefix(filename) && | |
126 | filename[2] == '\0') | |
127 | return 1; | |
128 | if (strstart(filename, "\\\\.\\", NULL) || | |
129 | strstart(filename, "//./", NULL)) | |
130 | return 1; | |
131 | return 0; | |
132 | } | |
133 | #endif | |
134 | ||
339064d5 KW |
135 | size_t bdrv_opt_mem_align(BlockDriverState *bs) |
136 | { | |
137 | if (!bs || !bs->drv) { | |
459b4e66 | 138 | /* page size or 4k (hdd sector size) should be on the safe side */ |
8e3b0cbb | 139 | return MAX(4096, qemu_real_host_page_size()); |
339064d5 | 140 | } |
384a48fb | 141 | IO_CODE(); |
339064d5 KW |
142 | |
143 | return bs->bl.opt_mem_alignment; | |
144 | } | |
145 | ||
4196d2f0 DL |
146 | size_t bdrv_min_mem_align(BlockDriverState *bs) |
147 | { | |
148 | if (!bs || !bs->drv) { | |
459b4e66 | 149 | /* page size or 4k (hdd sector size) should be on the safe side */ |
8e3b0cbb | 150 | return MAX(4096, qemu_real_host_page_size()); |
4196d2f0 | 151 | } |
384a48fb | 152 | IO_CODE(); |
4196d2f0 DL |
153 | |
154 | return bs->bl.min_mem_alignment; | |
155 | } | |
156 | ||
9e0b22f4 | 157 | /* check if the path starts with "<protocol>:" */ |
5c98415b | 158 | int path_has_protocol(const char *path) |
9e0b22f4 | 159 | { |
947995c0 PB |
160 | const char *p; |
161 | ||
9e0b22f4 SH |
162 | #ifdef _WIN32 |
163 | if (is_windows_drive(path) || | |
164 | is_windows_drive_prefix(path)) { | |
165 | return 0; | |
166 | } | |
947995c0 PB |
167 | p = path + strcspn(path, ":/\\"); |
168 | #else | |
169 | p = path + strcspn(path, ":/"); | |
9e0b22f4 SH |
170 | #endif |
171 | ||
947995c0 | 172 | return *p == ':'; |
9e0b22f4 SH |
173 | } |
174 | ||
83f64091 | 175 | int path_is_absolute(const char *path) |
3b0d4f61 | 176 | { |
21664424 FB |
177 | #ifdef _WIN32 |
178 | /* specific case for names like: "\\.\d:" */ | |
f53f4da9 | 179 | if (is_windows_drive(path) || is_windows_drive_prefix(path)) { |
21664424 | 180 | return 1; |
f53f4da9 PB |
181 | } |
182 | return (*path == '/' || *path == '\\'); | |
3b9f94e1 | 183 | #else |
f53f4da9 | 184 | return (*path == '/'); |
3b9f94e1 | 185 | #endif |
3b0d4f61 FB |
186 | } |
187 | ||
009b03aa | 188 | /* if filename is absolute, just return its duplicate. Otherwise, build a |
83f64091 FB |
189 | path to it by considering it is relative to base_path. URL are |
190 | supported. */ | |
009b03aa | 191 | char *path_combine(const char *base_path, const char *filename) |
3b0d4f61 | 192 | { |
009b03aa | 193 | const char *protocol_stripped = NULL; |
83f64091 | 194 | const char *p, *p1; |
009b03aa | 195 | char *result; |
83f64091 FB |
196 | int len; |
197 | ||
83f64091 | 198 | if (path_is_absolute(filename)) { |
009b03aa HR |
199 | return g_strdup(filename); |
200 | } | |
0d54a6fe | 201 | |
009b03aa HR |
202 | if (path_has_protocol(base_path)) { |
203 | protocol_stripped = strchr(base_path, ':'); | |
204 | if (protocol_stripped) { | |
205 | protocol_stripped++; | |
0d54a6fe | 206 | } |
009b03aa HR |
207 | } |
208 | p = protocol_stripped ?: base_path; | |
0d54a6fe | 209 | |
009b03aa | 210 | p1 = strrchr(base_path, '/'); |
3b9f94e1 | 211 | #ifdef _WIN32 |
009b03aa HR |
212 | { |
213 | const char *p2; | |
214 | p2 = strrchr(base_path, '\\'); | |
215 | if (!p1 || p2 > p1) { | |
216 | p1 = p2; | |
3b9f94e1 | 217 | } |
009b03aa | 218 | } |
3b9f94e1 | 219 | #endif |
009b03aa HR |
220 | if (p1) { |
221 | p1++; | |
222 | } else { | |
223 | p1 = base_path; | |
224 | } | |
225 | if (p1 > p) { | |
226 | p = p1; | |
3b0d4f61 | 227 | } |
009b03aa HR |
228 | len = p - base_path; |
229 | ||
230 | result = g_malloc(len + strlen(filename) + 1); | |
231 | memcpy(result, base_path, len); | |
232 | strcpy(result + len, filename); | |
233 | ||
234 | return result; | |
235 | } | |
236 | ||
03c320d8 HR |
237 | /* |
238 | * Helper function for bdrv_parse_filename() implementations to remove optional | |
239 | * protocol prefixes (especially "file:") from a filename and for putting the | |
240 | * stripped filename into the options QDict if there is such a prefix. | |
241 | */ | |
242 | void bdrv_parse_filename_strip_prefix(const char *filename, const char *prefix, | |
243 | QDict *options) | |
244 | { | |
245 | if (strstart(filename, prefix, &filename)) { | |
246 | /* Stripping the explicit protocol prefix may result in a protocol | |
247 | * prefix being (wrongly) detected (if the filename contains a colon) */ | |
248 | if (path_has_protocol(filename)) { | |
18cf67c5 | 249 | GString *fat_filename; |
03c320d8 HR |
250 | |
251 | /* This means there is some colon before the first slash; therefore, | |
252 | * this cannot be an absolute path */ | |
253 | assert(!path_is_absolute(filename)); | |
254 | ||
255 | /* And we can thus fix the protocol detection issue by prefixing it | |
256 | * by "./" */ | |
18cf67c5 MA |
257 | fat_filename = g_string_new("./"); |
258 | g_string_append(fat_filename, filename); | |
03c320d8 | 259 | |
18cf67c5 | 260 | assert(!path_has_protocol(fat_filename->str)); |
03c320d8 | 261 | |
18cf67c5 MA |
262 | qdict_put(options, "filename", |
263 | qstring_from_gstring(fat_filename)); | |
03c320d8 HR |
264 | } else { |
265 | /* If no protocol prefix was detected, we can use the shortened | |
266 | * filename as-is */ | |
267 | qdict_put_str(options, "filename", filename); | |
268 | } | |
269 | } | |
270 | } | |
271 | ||
272 | ||
9c5e6594 KW |
273 | /* Returns whether the image file is opened as read-only. Note that this can |
274 | * return false and writing to the image file is still not possible because the | |
275 | * image is inactivated. */ | |
93ed524e JC |
276 | bool bdrv_is_read_only(BlockDriverState *bs) |
277 | { | |
384a48fb | 278 | IO_CODE(); |
975da073 | 279 | return !(bs->open_flags & BDRV_O_RDWR); |
93ed524e JC |
280 | } |
281 | ||
10e5d707 KW |
282 | static int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, |
283 | bool ignore_allow_rdw, Error **errp) | |
fe5241bf | 284 | { |
384a48fb EGE |
285 | IO_CODE(); |
286 | ||
e2b8247a JC |
287 | /* Do not set read_only if copy_on_read is enabled */ |
288 | if (bs->copy_on_read && read_only) { | |
289 | error_setg(errp, "Can't set node '%s' to r/o with copy-on-read enabled", | |
290 | bdrv_get_device_or_node_name(bs)); | |
291 | return -EINVAL; | |
292 | } | |
293 | ||
d6fcdf06 | 294 | /* Do not clear read_only if it is prohibited */ |
54a32bfe KW |
295 | if (!read_only && !(bs->open_flags & BDRV_O_ALLOW_RDWR) && |
296 | !ignore_allow_rdw) | |
297 | { | |
d6fcdf06 JC |
298 | error_setg(errp, "Node '%s' is read only", |
299 | bdrv_get_device_or_node_name(bs)); | |
300 | return -EPERM; | |
301 | } | |
302 | ||
45803a03 JC |
303 | return 0; |
304 | } | |
305 | ||
eaa2410f KW |
306 | /* |
307 | * Called by a driver that can only provide a read-only image. | |
308 | * | |
309 | * Returns 0 if the node is already read-only or it could switch the node to | |
310 | * read-only because BDRV_O_AUTO_RDONLY is set. | |
311 | * | |
312 | * Returns -EACCES if the node is read-write and BDRV_O_AUTO_RDONLY is not set | |
313 | * or bdrv_can_set_read_only() forbids making the node read-only. If @errmsg | |
314 | * is not NULL, it is used as the error message for the Error object. | |
315 | */ | |
316 | int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, | |
317 | Error **errp) | |
45803a03 JC |
318 | { |
319 | int ret = 0; | |
384a48fb | 320 | IO_CODE(); |
45803a03 | 321 | |
eaa2410f KW |
322 | if (!(bs->open_flags & BDRV_O_RDWR)) { |
323 | return 0; | |
324 | } | |
325 | if (!(bs->open_flags & BDRV_O_AUTO_RDONLY)) { | |
326 | goto fail; | |
45803a03 JC |
327 | } |
328 | ||
eaa2410f KW |
329 | ret = bdrv_can_set_read_only(bs, true, false, NULL); |
330 | if (ret < 0) { | |
331 | goto fail; | |
eeae6a59 KW |
332 | } |
333 | ||
eaa2410f KW |
334 | bs->open_flags &= ~BDRV_O_RDWR; |
335 | ||
e2b8247a | 336 | return 0; |
eaa2410f KW |
337 | |
338 | fail: | |
339 | error_setg(errp, "%s", errmsg ?: "Image is read-only"); | |
340 | return -EACCES; | |
fe5241bf JC |
341 | } |
342 | ||
645ae7d8 HR |
343 | /* |
344 | * If @backing is empty, this function returns NULL without setting | |
345 | * @errp. In all other cases, NULL will only be returned with @errp | |
346 | * set. | |
347 | * | |
348 | * Therefore, a return value of NULL without @errp set means that | |
349 | * there is no backing file; if @errp is set, there is one but its | |
350 | * absolute filename cannot be generated. | |
351 | */ | |
352 | char *bdrv_get_full_backing_filename_from_filename(const char *backed, | |
353 | const char *backing, | |
354 | Error **errp) | |
dc5a1371 | 355 | { |
645ae7d8 HR |
356 | if (backing[0] == '\0') { |
357 | return NULL; | |
358 | } else if (path_has_protocol(backing) || path_is_absolute(backing)) { | |
359 | return g_strdup(backing); | |
9f07429e HR |
360 | } else if (backed[0] == '\0' || strstart(backed, "json:", NULL)) { |
361 | error_setg(errp, "Cannot use relative backing file names for '%s'", | |
362 | backed); | |
645ae7d8 | 363 | return NULL; |
dc5a1371 | 364 | } else { |
645ae7d8 | 365 | return path_combine(backed, backing); |
dc5a1371 PB |
366 | } |
367 | } | |
368 | ||
9f4793d8 HR |
369 | /* |
370 | * If @filename is empty or NULL, this function returns NULL without | |
371 | * setting @errp. In all other cases, NULL will only be returned with | |
372 | * @errp set. | |
373 | */ | |
374 | static char *bdrv_make_absolute_filename(BlockDriverState *relative_to, | |
375 | const char *filename, Error **errp) | |
0a82855a | 376 | { |
8df68616 | 377 | char *dir, *full_name; |
9f4793d8 | 378 | |
8df68616 HR |
379 | if (!filename || filename[0] == '\0') { |
380 | return NULL; | |
381 | } else if (path_has_protocol(filename) || path_is_absolute(filename)) { | |
382 | return g_strdup(filename); | |
383 | } | |
9f07429e | 384 | |
8df68616 HR |
385 | dir = bdrv_dirname(relative_to, errp); |
386 | if (!dir) { | |
387 | return NULL; | |
388 | } | |
f30c66ba | 389 | |
8df68616 HR |
390 | full_name = g_strconcat(dir, filename, NULL); |
391 | g_free(dir); | |
392 | return full_name; | |
9f4793d8 HR |
393 | } |
394 | ||
395 | char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp) | |
396 | { | |
f791bf7f | 397 | GLOBAL_STATE_CODE(); |
9f4793d8 | 398 | return bdrv_make_absolute_filename(bs, bs->backing_file, errp); |
0a82855a HR |
399 | } |
400 | ||
0eb7217e SH |
401 | void bdrv_register(BlockDriver *bdrv) |
402 | { | |
a15f08dc | 403 | assert(bdrv->format_name); |
f791bf7f | 404 | GLOBAL_STATE_CODE(); |
8a22f02a | 405 | QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list); |
ea2384d3 | 406 | } |
b338082b | 407 | |
e4e9986b MA |
408 | BlockDriverState *bdrv_new(void) |
409 | { | |
410 | BlockDriverState *bs; | |
411 | int i; | |
412 | ||
f791bf7f EGE |
413 | GLOBAL_STATE_CODE(); |
414 | ||
5839e53b | 415 | bs = g_new0(BlockDriverState, 1); |
e4654d2d | 416 | QLIST_INIT(&bs->dirty_bitmaps); |
fbe40ff7 FZ |
417 | for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { |
418 | QLIST_INIT(&bs->op_blockers[i]); | |
419 | } | |
fa9185fc | 420 | qemu_mutex_init(&bs->reqs_lock); |
2119882c | 421 | qemu_mutex_init(&bs->dirty_bitmap_mutex); |
9fcb0251 | 422 | bs->refcnt = 1; |
dcd04228 | 423 | bs->aio_context = qemu_get_aio_context(); |
d7d512f6 | 424 | |
3ff2f67a EY |
425 | qemu_co_queue_init(&bs->flush_queue); |
426 | ||
0bc329fb HR |
427 | qemu_co_mutex_init(&bs->bsc_modify_lock); |
428 | bs->block_status_cache = g_new0(BdrvBlockStatusCache, 1); | |
429 | ||
0f12264e KW |
430 | for (i = 0; i < bdrv_drain_all_count; i++) { |
431 | bdrv_drained_begin(bs); | |
432 | } | |
433 | ||
2c1d04e0 HR |
434 | QTAILQ_INSERT_TAIL(&all_bdrv_states, bs, bs_list); |
435 | ||
b338082b FB |
436 | return bs; |
437 | } | |
438 | ||
88d88798 | 439 | static BlockDriver *bdrv_do_find_format(const char *format_name) |
ea2384d3 FB |
440 | { |
441 | BlockDriver *drv1; | |
bdb73476 | 442 | GLOBAL_STATE_CODE(); |
88d88798 | 443 | |
8a22f02a SH |
444 | QLIST_FOREACH(drv1, &bdrv_drivers, list) { |
445 | if (!strcmp(drv1->format_name, format_name)) { | |
ea2384d3 | 446 | return drv1; |
8a22f02a | 447 | } |
ea2384d3 | 448 | } |
88d88798 | 449 | |
ea2384d3 FB |
450 | return NULL; |
451 | } | |
452 | ||
88d88798 MM |
453 | BlockDriver *bdrv_find_format(const char *format_name) |
454 | { | |
455 | BlockDriver *drv1; | |
456 | int i; | |
457 | ||
f791bf7f EGE |
458 | GLOBAL_STATE_CODE(); |
459 | ||
88d88798 MM |
460 | drv1 = bdrv_do_find_format(format_name); |
461 | if (drv1) { | |
462 | return drv1; | |
463 | } | |
464 | ||
465 | /* The driver isn't registered, maybe we need to load a module */ | |
466 | for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); ++i) { | |
467 | if (!strcmp(block_driver_modules[i].format_name, format_name)) { | |
c551fb0b CF |
468 | Error *local_err = NULL; |
469 | int rv = block_module_load(block_driver_modules[i].library_name, | |
470 | &local_err); | |
471 | if (rv > 0) { | |
472 | return bdrv_do_find_format(format_name); | |
473 | } else if (rv < 0) { | |
474 | error_report_err(local_err); | |
475 | } | |
88d88798 MM |
476 | break; |
477 | } | |
478 | } | |
c551fb0b | 479 | return NULL; |
88d88798 MM |
480 | } |
481 | ||
9ac404c5 | 482 | static int bdrv_format_is_whitelisted(const char *format_name, bool read_only) |
eb852011 | 483 | { |
b64ec4e4 FZ |
484 | static const char *whitelist_rw[] = { |
485 | CONFIG_BDRV_RW_WHITELIST | |
859aef02 | 486 | NULL |
b64ec4e4 FZ |
487 | }; |
488 | static const char *whitelist_ro[] = { | |
489 | CONFIG_BDRV_RO_WHITELIST | |
859aef02 | 490 | NULL |
eb852011 MA |
491 | }; |
492 | const char **p; | |
493 | ||
b64ec4e4 | 494 | if (!whitelist_rw[0] && !whitelist_ro[0]) { |
eb852011 | 495 | return 1; /* no whitelist, anything goes */ |
b64ec4e4 | 496 | } |
eb852011 | 497 | |
b64ec4e4 | 498 | for (p = whitelist_rw; *p; p++) { |
9ac404c5 | 499 | if (!strcmp(format_name, *p)) { |
eb852011 MA |
500 | return 1; |
501 | } | |
502 | } | |
b64ec4e4 FZ |
503 | if (read_only) { |
504 | for (p = whitelist_ro; *p; p++) { | |
9ac404c5 | 505 | if (!strcmp(format_name, *p)) { |
b64ec4e4 FZ |
506 | return 1; |
507 | } | |
508 | } | |
509 | } | |
eb852011 MA |
510 | return 0; |
511 | } | |
512 | ||
9ac404c5 AS |
513 | int bdrv_is_whitelisted(BlockDriver *drv, bool read_only) |
514 | { | |
f791bf7f | 515 | GLOBAL_STATE_CODE(); |
9ac404c5 AS |
516 | return bdrv_format_is_whitelisted(drv->format_name, read_only); |
517 | } | |
518 | ||
e6ff69bf DB |
519 | bool bdrv_uses_whitelist(void) |
520 | { | |
521 | return use_bdrv_whitelist; | |
522 | } | |
523 | ||
5b7e1542 ZYW |
524 | typedef struct CreateCo { |
525 | BlockDriver *drv; | |
526 | char *filename; | |
83d0521a | 527 | QemuOpts *opts; |
5b7e1542 | 528 | int ret; |
cc84d90f | 529 | Error *err; |
5b7e1542 ZYW |
530 | } CreateCo; |
531 | ||
741443eb EGE |
532 | int coroutine_fn bdrv_co_create(BlockDriver *drv, const char *filename, |
533 | QemuOpts *opts, Error **errp) | |
5b7e1542 | 534 | { |
cc84d90f | 535 | int ret; |
84bdf21f EGE |
536 | GLOBAL_STATE_CODE(); |
537 | ERRP_GUARD(); | |
538 | ||
539 | if (!drv->bdrv_co_create_opts) { | |
540 | error_setg(errp, "Driver '%s' does not support image creation", | |
541 | drv->format_name); | |
542 | return -ENOTSUP; | |
543 | } | |
544 | ||
545 | ret = drv->bdrv_co_create_opts(drv, filename, opts, errp); | |
546 | if (ret < 0 && !*errp) { | |
547 | error_setg_errno(errp, -ret, "Could not create image"); | |
548 | } | |
cc84d90f | 549 | |
84bdf21f EGE |
550 | return ret; |
551 | } | |
552 | ||
fd17146c HR |
553 | /** |
554 | * Helper function for bdrv_create_file_fallback(): Resize @blk to at | |
555 | * least the given @minimum_size. | |
556 | * | |
557 | * On success, return @blk's actual length. | |
558 | * Otherwise, return -errno. | |
559 | */ | |
84569a7d PB |
560 | static int64_t coroutine_fn GRAPH_UNLOCKED |
561 | create_file_fallback_truncate(BlockBackend *blk, int64_t minimum_size, | |
562 | Error **errp) | |
84a12e66 | 563 | { |
cc84d90f | 564 | Error *local_err = NULL; |
fd17146c | 565 | int64_t size; |
cc84d90f | 566 | int ret; |
84a12e66 | 567 | |
bdb73476 EGE |
568 | GLOBAL_STATE_CODE(); |
569 | ||
84569a7d PB |
570 | ret = blk_co_truncate(blk, minimum_size, false, PREALLOC_MODE_OFF, 0, |
571 | &local_err); | |
fd17146c HR |
572 | if (ret < 0 && ret != -ENOTSUP) { |
573 | error_propagate(errp, local_err); | |
574 | return ret; | |
575 | } | |
576 | ||
84569a7d | 577 | size = blk_co_getlength(blk); |
fd17146c HR |
578 | if (size < 0) { |
579 | error_free(local_err); | |
580 | error_setg_errno(errp, -size, | |
581 | "Failed to inquire the new image file's length"); | |
582 | return size; | |
583 | } | |
584 | ||
585 | if (size < minimum_size) { | |
586 | /* Need to grow the image, but we failed to do that */ | |
587 | error_propagate(errp, local_err); | |
588 | return -ENOTSUP; | |
589 | } | |
590 | ||
591 | error_free(local_err); | |
592 | local_err = NULL; | |
593 | ||
594 | return size; | |
595 | } | |
596 | ||
597 | /** | |
598 | * Helper function for bdrv_create_file_fallback(): Zero the first | |
599 | * sector to remove any potentially pre-existing image header. | |
600 | */ | |
881a4c55 PB |
601 | static int coroutine_fn |
602 | create_file_fallback_zero_first_sector(BlockBackend *blk, | |
603 | int64_t current_size, | |
604 | Error **errp) | |
fd17146c HR |
605 | { |
606 | int64_t bytes_to_clear; | |
607 | int ret; | |
608 | ||
bdb73476 EGE |
609 | GLOBAL_STATE_CODE(); |
610 | ||
fd17146c HR |
611 | bytes_to_clear = MIN(current_size, BDRV_SECTOR_SIZE); |
612 | if (bytes_to_clear) { | |
ce47ff20 | 613 | ret = blk_co_pwrite_zeroes(blk, 0, bytes_to_clear, BDRV_REQ_MAY_UNMAP); |
fd17146c HR |
614 | if (ret < 0) { |
615 | error_setg_errno(errp, -ret, | |
616 | "Failed to clear the new image's first sector"); | |
617 | return ret; | |
618 | } | |
619 | } | |
620 | ||
621 | return 0; | |
622 | } | |
623 | ||
5a5e7f8c ML |
624 | /** |
625 | * Simple implementation of bdrv_co_create_opts for protocol drivers | |
626 | * which only support creation via opening a file | |
627 | * (usually existing raw storage device) | |
628 | */ | |
629 | int coroutine_fn bdrv_co_create_opts_simple(BlockDriver *drv, | |
630 | const char *filename, | |
631 | QemuOpts *opts, | |
632 | Error **errp) | |
fd17146c HR |
633 | { |
634 | BlockBackend *blk; | |
eeea1faa | 635 | QDict *options; |
fd17146c HR |
636 | int64_t size = 0; |
637 | char *buf = NULL; | |
638 | PreallocMode prealloc; | |
639 | Error *local_err = NULL; | |
640 | int ret; | |
641 | ||
b4ad82aa EGE |
642 | GLOBAL_STATE_CODE(); |
643 | ||
fd17146c HR |
644 | size = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0); |
645 | buf = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC); | |
646 | prealloc = qapi_enum_parse(&PreallocMode_lookup, buf, | |
647 | PREALLOC_MODE_OFF, &local_err); | |
648 | g_free(buf); | |
649 | if (local_err) { | |
650 | error_propagate(errp, local_err); | |
651 | return -EINVAL; | |
652 | } | |
653 | ||
654 | if (prealloc != PREALLOC_MODE_OFF) { | |
655 | error_setg(errp, "Unsupported preallocation mode '%s'", | |
656 | PreallocMode_str(prealloc)); | |
657 | return -ENOTSUP; | |
658 | } | |
659 | ||
eeea1faa | 660 | options = qdict_new(); |
fd17146c HR |
661 | qdict_put_str(options, "driver", drv->format_name); |
662 | ||
be1a732c KW |
663 | blk = blk_co_new_open(filename, NULL, options, |
664 | BDRV_O_RDWR | BDRV_O_RESIZE, errp); | |
fd17146c | 665 | if (!blk) { |
81624867 HC |
666 | error_prepend(errp, "Protocol driver '%s' does not support creating " |
667 | "new images, so an existing image must be selected as " | |
668 | "the target; however, opening the given target as an " | |
669 | "existing image failed: ", | |
fd17146c HR |
670 | drv->format_name); |
671 | return -EINVAL; | |
672 | } | |
673 | ||
674 | size = create_file_fallback_truncate(blk, size, errp); | |
675 | if (size < 0) { | |
676 | ret = size; | |
677 | goto out; | |
678 | } | |
679 | ||
680 | ret = create_file_fallback_zero_first_sector(blk, size, errp); | |
681 | if (ret < 0) { | |
682 | goto out; | |
683 | } | |
684 | ||
685 | ret = 0; | |
686 | out: | |
b2ab5f54 | 687 | blk_co_unref(blk); |
fd17146c HR |
688 | return ret; |
689 | } | |
690 | ||
2475a0d0 EGE |
691 | int coroutine_fn bdrv_co_create_file(const char *filename, QemuOpts *opts, |
692 | Error **errp) | |
fd17146c | 693 | { |
729222af | 694 | QemuOpts *protocol_opts; |
fd17146c | 695 | BlockDriver *drv; |
729222af SG |
696 | QDict *qdict; |
697 | int ret; | |
fd17146c | 698 | |
f791bf7f EGE |
699 | GLOBAL_STATE_CODE(); |
700 | ||
b65a5e12 | 701 | drv = bdrv_find_protocol(filename, true, errp); |
84a12e66 | 702 | if (drv == NULL) { |
16905d71 | 703 | return -ENOENT; |
84a12e66 CH |
704 | } |
705 | ||
729222af SG |
706 | if (!drv->create_opts) { |
707 | error_setg(errp, "Driver '%s' does not support image creation", | |
708 | drv->format_name); | |
709 | return -ENOTSUP; | |
710 | } | |
711 | ||
712 | /* | |
713 | * 'opts' contains a QemuOptsList with a combination of format and protocol | |
714 | * default values. | |
715 | * | |
716 | * The format properly removes its options, but the default values remain | |
717 | * in 'opts->list'. So if the protocol has options with the same name | |
718 | * (e.g. rbd has 'cluster_size' as qcow2), it will see the default values | |
719 | * of the format, since for overlapping options, the format wins. | |
720 | * | |
721 | * To avoid this issue, lets convert QemuOpts to QDict, in this way we take | |
722 | * only the set options, and then convert it back to QemuOpts, using the | |
723 | * create_opts of the protocol. So the new QemuOpts, will contain only the | |
724 | * protocol defaults. | |
725 | */ | |
726 | qdict = qemu_opts_to_qdict(opts, NULL); | |
727 | protocol_opts = qemu_opts_from_qdict(drv->create_opts, qdict, errp); | |
728 | if (protocol_opts == NULL) { | |
729 | ret = -EINVAL; | |
730 | goto out; | |
731 | } | |
732 | ||
2475a0d0 | 733 | ret = bdrv_co_create(drv, filename, protocol_opts, errp); |
729222af SG |
734 | out: |
735 | qemu_opts_del(protocol_opts); | |
736 | qobject_unref(qdict); | |
737 | return ret; | |
84a12e66 CH |
738 | } |
739 | ||
e1d7f8bb DHB |
740 | int coroutine_fn bdrv_co_delete_file(BlockDriverState *bs, Error **errp) |
741 | { | |
742 | Error *local_err = NULL; | |
743 | int ret; | |
744 | ||
384a48fb | 745 | IO_CODE(); |
e1d7f8bb | 746 | assert(bs != NULL); |
48aef794 | 747 | assert_bdrv_graph_readable(); |
e1d7f8bb DHB |
748 | |
749 | if (!bs->drv) { | |
750 | error_setg(errp, "Block node '%s' is not opened", bs->filename); | |
751 | return -ENOMEDIUM; | |
752 | } | |
753 | ||
754 | if (!bs->drv->bdrv_co_delete_file) { | |
755 | error_setg(errp, "Driver '%s' does not support image deletion", | |
756 | bs->drv->format_name); | |
757 | return -ENOTSUP; | |
758 | } | |
759 | ||
760 | ret = bs->drv->bdrv_co_delete_file(bs, &local_err); | |
761 | if (ret < 0) { | |
762 | error_propagate(errp, local_err); | |
763 | } | |
764 | ||
765 | return ret; | |
766 | } | |
767 | ||
a890f08e ML |
768 | void coroutine_fn bdrv_co_delete_file_noerr(BlockDriverState *bs) |
769 | { | |
770 | Error *local_err = NULL; | |
771 | int ret; | |
384a48fb | 772 | IO_CODE(); |
a890f08e ML |
773 | |
774 | if (!bs) { | |
775 | return; | |
776 | } | |
777 | ||
778 | ret = bdrv_co_delete_file(bs, &local_err); | |
779 | /* | |
780 | * ENOTSUP will happen if the block driver doesn't support | |
781 | * the 'bdrv_co_delete_file' interface. This is a predictable | |
782 | * scenario and shouldn't be reported back to the user. | |
783 | */ | |
784 | if (ret == -ENOTSUP) { | |
785 | error_free(local_err); | |
786 | } else if (ret < 0) { | |
787 | error_report_err(local_err); | |
788 | } | |
789 | } | |
790 | ||
892b7de8 ET |
791 | /** |
792 | * Try to get @bs's logical and physical block size. | |
793 | * On success, store them in @bsz struct and return 0. | |
794 | * On failure return -errno. | |
795 | * @bs must not be empty. | |
796 | */ | |
797 | int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz) | |
798 | { | |
799 | BlockDriver *drv = bs->drv; | |
93393e69 | 800 | BlockDriverState *filtered = bdrv_filter_bs(bs); |
f791bf7f | 801 | GLOBAL_STATE_CODE(); |
892b7de8 ET |
802 | |
803 | if (drv && drv->bdrv_probe_blocksizes) { | |
804 | return drv->bdrv_probe_blocksizes(bs, bsz); | |
93393e69 HR |
805 | } else if (filtered) { |
806 | return bdrv_probe_blocksizes(filtered, bsz); | |
892b7de8 ET |
807 | } |
808 | ||
809 | return -ENOTSUP; | |
810 | } | |
811 | ||
812 | /** | |
813 | * Try to get @bs's geometry (cyls, heads, sectors). | |
814 | * On success, store them in @geo struct and return 0. | |
815 | * On failure return -errno. | |
816 | * @bs must not be empty. | |
817 | */ | |
818 | int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo) | |
819 | { | |
820 | BlockDriver *drv = bs->drv; | |
93393e69 | 821 | BlockDriverState *filtered = bdrv_filter_bs(bs); |
f791bf7f | 822 | GLOBAL_STATE_CODE(); |
892b7de8 ET |
823 | |
824 | if (drv && drv->bdrv_probe_geometry) { | |
825 | return drv->bdrv_probe_geometry(bs, geo); | |
93393e69 HR |
826 | } else if (filtered) { |
827 | return bdrv_probe_geometry(filtered, geo); | |
892b7de8 ET |
828 | } |
829 | ||
830 | return -ENOTSUP; | |
831 | } | |
832 | ||
eba25057 JM |
833 | /* |
834 | * Create a uniquely-named empty temporary file. | |
69fbfff9 BM |
835 | * Return the actual file name used upon success, otherwise NULL. |
836 | * This string should be freed with g_free() when not needed any longer. | |
837 | * | |
838 | * Note: creating a temporary file for the caller to (re)open is | |
839 | * inherently racy. Use g_file_open_tmp() instead whenever practical. | |
eba25057 | 840 | */ |
69fbfff9 | 841 | char *create_tmp_file(Error **errp) |
d5249393 | 842 | { |
67b915a5 | 843 | int fd; |
7ccfb2eb | 844 | const char *tmpdir; |
69fbfff9 BM |
845 | g_autofree char *filename = NULL; |
846 | ||
847 | tmpdir = g_get_tmp_dir(); | |
848 | #ifndef _WIN32 | |
849 | /* | |
850 | * See commit 69bef79 ("block: use /var/tmp instead of /tmp for -snapshot") | |
851 | * | |
852 | * This function is used to create temporary disk images (like -snapshot), | |
853 | * so the files can become very large. /tmp is often a tmpfs where as | |
854 | * /var/tmp is usually on a disk, so more appropriate for disk images. | |
855 | */ | |
856 | if (!g_strcmp0(tmpdir, "/tmp")) { | |
69bef793 AS |
857 | tmpdir = "/var/tmp"; |
858 | } | |
69fbfff9 BM |
859 | #endif |
860 | ||
861 | filename = g_strdup_printf("%s/vl.XXXXXX", tmpdir); | |
862 | fd = g_mkstemp(filename); | |
fe235a06 | 863 | if (fd < 0) { |
69fbfff9 BM |
864 | error_setg_errno(errp, errno, "Could not open temporary file '%s'", |
865 | filename); | |
866 | return NULL; | |
eba25057 | 867 | } |
6b6471ee | 868 | close(fd); |
69fbfff9 BM |
869 | |
870 | return g_steal_pointer(&filename); | |
eba25057 | 871 | } |
fc01f7e7 | 872 | |
84a12e66 CH |
873 | /* |
874 | * Detect host devices. By convention, /dev/cdrom[N] is always | |
875 | * recognized as a host CDROM. | |
876 | */ | |
877 | static BlockDriver *find_hdev_driver(const char *filename) | |
878 | { | |
879 | int score_max = 0, score; | |
880 | BlockDriver *drv = NULL, *d; | |
bdb73476 | 881 | GLOBAL_STATE_CODE(); |
84a12e66 CH |
882 | |
883 | QLIST_FOREACH(d, &bdrv_drivers, list) { | |
884 | if (d->bdrv_probe_device) { | |
885 | score = d->bdrv_probe_device(filename); | |
886 | if (score > score_max) { | |
887 | score_max = score; | |
888 | drv = d; | |
889 | } | |
890 | } | |
891 | } | |
892 | ||
893 | return drv; | |
894 | } | |
895 | ||
88d88798 MM |
896 | static BlockDriver *bdrv_do_find_protocol(const char *protocol) |
897 | { | |
898 | BlockDriver *drv1; | |
bdb73476 | 899 | GLOBAL_STATE_CODE(); |
88d88798 MM |
900 | |
901 | QLIST_FOREACH(drv1, &bdrv_drivers, list) { | |
902 | if (drv1->protocol_name && !strcmp(drv1->protocol_name, protocol)) { | |
903 | return drv1; | |
904 | } | |
905 | } | |
906 | ||
907 | return NULL; | |
908 | } | |
909 | ||
98289620 | 910 | BlockDriver *bdrv_find_protocol(const char *filename, |
b65a5e12 HR |
911 | bool allow_protocol_prefix, |
912 | Error **errp) | |
83f64091 FB |
913 | { |
914 | BlockDriver *drv1; | |
915 | char protocol[128]; | |
1cec71e3 | 916 | int len; |
83f64091 | 917 | const char *p; |
88d88798 | 918 | int i; |
19cb3738 | 919 | |
f791bf7f | 920 | GLOBAL_STATE_CODE(); |
66f82cee KW |
921 | /* TODO Drivers without bdrv_file_open must be specified explicitly */ |
922 | ||
39508e7a CH |
923 | /* |
924 | * XXX(hch): we really should not let host device detection | |
925 | * override an explicit protocol specification, but moving this | |
926 | * later breaks access to device names with colons in them. | |
927 | * Thanks to the brain-dead persistent naming schemes on udev- | |
928 | * based Linux systems those actually are quite common. | |
929 | */ | |
930 | drv1 = find_hdev_driver(filename); | |
931 | if (drv1) { | |
932 | return drv1; | |
933 | } | |
934 | ||
98289620 | 935 | if (!path_has_protocol(filename) || !allow_protocol_prefix) { |
ef810437 | 936 | return &bdrv_file; |
84a12e66 | 937 | } |
98289620 | 938 | |
9e0b22f4 SH |
939 | p = strchr(filename, ':'); |
940 | assert(p != NULL); | |
1cec71e3 AL |
941 | len = p - filename; |
942 | if (len > sizeof(protocol) - 1) | |
943 | len = sizeof(protocol) - 1; | |
944 | memcpy(protocol, filename, len); | |
945 | protocol[len] = '\0'; | |
88d88798 MM |
946 | |
947 | drv1 = bdrv_do_find_protocol(protocol); | |
948 | if (drv1) { | |
949 | return drv1; | |
950 | } | |
951 | ||
952 | for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); ++i) { | |
953 | if (block_driver_modules[i].protocol_name && | |
954 | !strcmp(block_driver_modules[i].protocol_name, protocol)) { | |
c551fb0b CF |
955 | int rv = block_module_load(block_driver_modules[i].library_name, errp); |
956 | if (rv > 0) { | |
957 | drv1 = bdrv_do_find_protocol(protocol); | |
958 | } else if (rv < 0) { | |
959 | return NULL; | |
960 | } | |
88d88798 | 961 | break; |
8a22f02a | 962 | } |
83f64091 | 963 | } |
b65a5e12 | 964 | |
88d88798 MM |
965 | if (!drv1) { |
966 | error_setg(errp, "Unknown protocol '%s'", protocol); | |
967 | } | |
968 | return drv1; | |
83f64091 FB |
969 | } |
970 | ||
c6684249 MA |
971 | /* |
972 | * Guess image format by probing its contents. | |
973 | * This is not a good idea when your image is raw (CVE-2008-2004), but | |
974 | * we do it anyway for backward compatibility. | |
975 | * | |
976 | * @buf contains the image's first @buf_size bytes. | |
7cddd372 KW |
977 | * @buf_size is the buffer size in bytes (generally BLOCK_PROBE_BUF_SIZE, |
978 | * but can be smaller if the image file is smaller) | |
c6684249 MA |
979 | * @filename is its filename. |
980 | * | |
981 | * For all block drivers, call the bdrv_probe() method to get its | |
982 | * probing score. | |
983 | * Return the first block driver with the highest probing score. | |
984 | */ | |
38f3ef57 KW |
985 | BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, |
986 | const char *filename) | |
c6684249 MA |
987 | { |
988 | int score_max = 0, score; | |
989 | BlockDriver *drv = NULL, *d; | |
967d7905 | 990 | IO_CODE(); |
c6684249 MA |
991 | |
992 | QLIST_FOREACH(d, &bdrv_drivers, list) { | |
993 | if (d->bdrv_probe) { | |
994 | score = d->bdrv_probe(buf, buf_size, filename); | |
995 | if (score > score_max) { | |
996 | score_max = score; | |
997 | drv = d; | |
998 | } | |
999 | } | |
1000 | } | |
1001 | ||
1002 | return drv; | |
1003 | } | |
1004 | ||
5696c6e3 | 1005 | static int find_image_format(BlockBackend *file, const char *filename, |
34b5d2c6 | 1006 | BlockDriver **pdrv, Error **errp) |
f3a5d3f8 | 1007 | { |
c6684249 | 1008 | BlockDriver *drv; |
7cddd372 | 1009 | uint8_t buf[BLOCK_PROBE_BUF_SIZE]; |
f500a6d3 | 1010 | int ret = 0; |
f8ea0b00 | 1011 | |
bdb73476 EGE |
1012 | GLOBAL_STATE_CODE(); |
1013 | ||
08a00559 | 1014 | /* Return the raw BlockDriver * to scsi-generic devices or empty drives */ |
5696c6e3 | 1015 | if (blk_is_sg(file) || !blk_is_inserted(file) || blk_getlength(file) == 0) { |
ef810437 | 1016 | *pdrv = &bdrv_raw; |
c98ac35d | 1017 | return ret; |
1a396859 | 1018 | } |
f8ea0b00 | 1019 | |
a9262f55 | 1020 | ret = blk_pread(file, 0, sizeof(buf), buf, 0); |
83f64091 | 1021 | if (ret < 0) { |
34b5d2c6 HR |
1022 | error_setg_errno(errp, -ret, "Could not read image for determining its " |
1023 | "format"); | |
c98ac35d SW |
1024 | *pdrv = NULL; |
1025 | return ret; | |
83f64091 FB |
1026 | } |
1027 | ||
bf5b16fa | 1028 | drv = bdrv_probe_all(buf, sizeof(buf), filename); |
c98ac35d | 1029 | if (!drv) { |
34b5d2c6 HR |
1030 | error_setg(errp, "Could not determine image format: No compatible " |
1031 | "driver found"); | |
bf5b16fa AF |
1032 | *pdrv = NULL; |
1033 | return -ENOENT; | |
c98ac35d | 1034 | } |
bf5b16fa | 1035 | |
c98ac35d | 1036 | *pdrv = drv; |
bf5b16fa | 1037 | return 0; |
ea2384d3 FB |
1038 | } |
1039 | ||
51762288 SH |
1040 | /** |
1041 | * Set the current 'total_sectors' value | |
65a9bb25 | 1042 | * Return 0 on success, -errno on error. |
51762288 | 1043 | */ |
c86422c5 EGE |
1044 | int coroutine_fn bdrv_co_refresh_total_sectors(BlockDriverState *bs, |
1045 | int64_t hint) | |
51762288 SH |
1046 | { |
1047 | BlockDriver *drv = bs->drv; | |
967d7905 | 1048 | IO_CODE(); |
8ab8140a | 1049 | assert_bdrv_graph_readable(); |
51762288 | 1050 | |
d470ad42 HR |
1051 | if (!drv) { |
1052 | return -ENOMEDIUM; | |
1053 | } | |
1054 | ||
c86422c5 | 1055 | /* Do not attempt drv->bdrv_co_getlength() on scsi-generic devices */ |
b192af8a | 1056 | if (bdrv_is_sg(bs)) |
396759ad NB |
1057 | return 0; |
1058 | ||
51762288 | 1059 | /* query actual device if possible, otherwise just trust the hint */ |
c86422c5 EGE |
1060 | if (drv->bdrv_co_getlength) { |
1061 | int64_t length = drv->bdrv_co_getlength(bs); | |
51762288 SH |
1062 | if (length < 0) { |
1063 | return length; | |
1064 | } | |
7e382003 | 1065 | hint = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE); |
51762288 SH |
1066 | } |
1067 | ||
1068 | bs->total_sectors = hint; | |
8b117001 VSO |
1069 | |
1070 | if (bs->total_sectors * BDRV_SECTOR_SIZE > BDRV_MAX_LENGTH) { | |
1071 | return -EFBIG; | |
1072 | } | |
1073 | ||
51762288 SH |
1074 | return 0; |
1075 | } | |
1076 | ||
cddff5ba KW |
1077 | /** |
1078 | * Combines a QDict of new block driver @options with any missing options taken | |
1079 | * from @old_options, so that leaving out an option defaults to its old value. | |
1080 | */ | |
1081 | static void bdrv_join_options(BlockDriverState *bs, QDict *options, | |
1082 | QDict *old_options) | |
1083 | { | |
da359909 | 1084 | GLOBAL_STATE_CODE(); |
cddff5ba KW |
1085 | if (bs->drv && bs->drv->bdrv_join_options) { |
1086 | bs->drv->bdrv_join_options(options, old_options); | |
1087 | } else { | |
1088 | qdict_join(options, old_options, false); | |
1089 | } | |
1090 | } | |
1091 | ||
543770bd AG |
1092 | static BlockdevDetectZeroesOptions bdrv_parse_detect_zeroes(QemuOpts *opts, |
1093 | int open_flags, | |
1094 | Error **errp) | |
1095 | { | |
1096 | Error *local_err = NULL; | |
1097 | char *value = qemu_opt_get_del(opts, "detect-zeroes"); | |
1098 | BlockdevDetectZeroesOptions detect_zeroes = | |
1099 | qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, value, | |
1100 | BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, &local_err); | |
bdb73476 | 1101 | GLOBAL_STATE_CODE(); |
543770bd AG |
1102 | g_free(value); |
1103 | if (local_err) { | |
1104 | error_propagate(errp, local_err); | |
1105 | return detect_zeroes; | |
1106 | } | |
1107 | ||
1108 | if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && | |
1109 | !(open_flags & BDRV_O_UNMAP)) | |
1110 | { | |
1111 | error_setg(errp, "setting detect-zeroes to unmap is not allowed " | |
1112 | "without setting discard operation to unmap"); | |
1113 | } | |
1114 | ||
1115 | return detect_zeroes; | |
1116 | } | |
1117 | ||
f80f2673 AM |
1118 | /** |
1119 | * Set open flags for aio engine | |
1120 | * | |
1121 | * Return 0 on success, -1 if the engine specified is invalid | |
1122 | */ | |
1123 | int bdrv_parse_aio(const char *mode, int *flags) | |
1124 | { | |
1125 | if (!strcmp(mode, "threads")) { | |
1126 | /* do nothing, default */ | |
1127 | } else if (!strcmp(mode, "native")) { | |
1128 | *flags |= BDRV_O_NATIVE_AIO; | |
1129 | #ifdef CONFIG_LINUX_IO_URING | |
1130 | } else if (!strcmp(mode, "io_uring")) { | |
1131 | *flags |= BDRV_O_IO_URING; | |
1132 | #endif | |
1133 | } else { | |
1134 | return -1; | |
1135 | } | |
1136 | ||
1137 | return 0; | |
1138 | } | |
1139 | ||
9e8f1835 PB |
1140 | /** |
1141 | * Set open flags for a given discard mode | |
1142 | * | |
1143 | * Return 0 on success, -1 if the discard mode was invalid. | |
1144 | */ | |
1145 | int bdrv_parse_discard_flags(const char *mode, int *flags) | |
1146 | { | |
1147 | *flags &= ~BDRV_O_UNMAP; | |
1148 | ||
1149 | if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) { | |
1150 | /* do nothing */ | |
1151 | } else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) { | |
1152 | *flags |= BDRV_O_UNMAP; | |
1153 | } else { | |
1154 | return -1; | |
1155 | } | |
1156 | ||
1157 | return 0; | |
1158 | } | |
1159 | ||
c3993cdc SH |
1160 | /** |
1161 | * Set open flags for a given cache mode | |
1162 | * | |
1163 | * Return 0 on success, -1 if the cache mode was invalid. | |
1164 | */ | |
53e8ae01 | 1165 | int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough) |
c3993cdc SH |
1166 | { |
1167 | *flags &= ~BDRV_O_CACHE_MASK; | |
1168 | ||
1169 | if (!strcmp(mode, "off") || !strcmp(mode, "none")) { | |
53e8ae01 KW |
1170 | *writethrough = false; |
1171 | *flags |= BDRV_O_NOCACHE; | |
92196b2f | 1172 | } else if (!strcmp(mode, "directsync")) { |
53e8ae01 | 1173 | *writethrough = true; |
92196b2f | 1174 | *flags |= BDRV_O_NOCACHE; |
c3993cdc | 1175 | } else if (!strcmp(mode, "writeback")) { |
53e8ae01 | 1176 | *writethrough = false; |
c3993cdc | 1177 | } else if (!strcmp(mode, "unsafe")) { |
53e8ae01 | 1178 | *writethrough = false; |
c3993cdc SH |
1179 | *flags |= BDRV_O_NO_FLUSH; |
1180 | } else if (!strcmp(mode, "writethrough")) { | |
53e8ae01 | 1181 | *writethrough = true; |
c3993cdc SH |
1182 | } else { |
1183 | return -1; | |
1184 | } | |
1185 | ||
1186 | return 0; | |
1187 | } | |
1188 | ||
b5411555 KW |
1189 | static char *bdrv_child_get_parent_desc(BdrvChild *c) |
1190 | { | |
1191 | BlockDriverState *parent = c->opaque; | |
2c0a3acb | 1192 | return g_strdup_printf("node '%s'", bdrv_get_node_name(parent)); |
b5411555 KW |
1193 | } |
1194 | ||
20018e12 KW |
1195 | static void bdrv_child_cb_drained_begin(BdrvChild *child) |
1196 | { | |
1197 | BlockDriverState *bs = child->opaque; | |
a82a3bd1 | 1198 | bdrv_do_drained_begin_quiesce(bs, NULL); |
20018e12 KW |
1199 | } |
1200 | ||
89bd0305 KW |
1201 | static bool bdrv_child_cb_drained_poll(BdrvChild *child) |
1202 | { | |
1203 | BlockDriverState *bs = child->opaque; | |
299403ae | 1204 | return bdrv_drain_poll(bs, NULL, false); |
89bd0305 KW |
1205 | } |
1206 | ||
2f65df6e | 1207 | static void bdrv_child_cb_drained_end(BdrvChild *child) |
20018e12 KW |
1208 | { |
1209 | BlockDriverState *bs = child->opaque; | |
2f65df6e | 1210 | bdrv_drained_end(bs); |
20018e12 KW |
1211 | } |
1212 | ||
38701b6a KW |
1213 | static int bdrv_child_cb_inactivate(BdrvChild *child) |
1214 | { | |
1215 | BlockDriverState *bs = child->opaque; | |
bdb73476 | 1216 | GLOBAL_STATE_CODE(); |
38701b6a KW |
1217 | assert(bs->open_flags & BDRV_O_INACTIVE); |
1218 | return 0; | |
1219 | } | |
1220 | ||
27633e74 EGE |
1221 | static bool bdrv_child_cb_change_aio_ctx(BdrvChild *child, AioContext *ctx, |
1222 | GHashTable *visited, Transaction *tran, | |
1223 | Error **errp) | |
53a7d041 KW |
1224 | { |
1225 | BlockDriverState *bs = child->opaque; | |
27633e74 | 1226 | return bdrv_change_aio_context(bs, ctx, visited, tran, errp); |
53a7d041 KW |
1227 | } |
1228 | ||
b1e6fc08 | 1229 | /* |
73176bee KW |
1230 | * Returns the options and flags that a temporary snapshot should get, based on |
1231 | * the originally requested flags (the originally requested image will have | |
1232 | * flags like a backing file) | |
b1e6fc08 | 1233 | */ |
73176bee KW |
1234 | static void bdrv_temp_snapshot_options(int *child_flags, QDict *child_options, |
1235 | int parent_flags, QDict *parent_options) | |
b1e6fc08 | 1236 | { |
bdb73476 | 1237 | GLOBAL_STATE_CODE(); |
73176bee KW |
1238 | *child_flags = (parent_flags & ~BDRV_O_SNAPSHOT) | BDRV_O_TEMPORARY; |
1239 | ||
1240 | /* For temporary files, unconditional cache=unsafe is fine */ | |
73176bee KW |
1241 | qdict_set_default_str(child_options, BDRV_OPT_CACHE_DIRECT, "off"); |
1242 | qdict_set_default_str(child_options, BDRV_OPT_CACHE_NO_FLUSH, "on"); | |
41869044 | 1243 | |
3f48686f | 1244 | /* Copy the read-only and discard options from the parent */ |
f87a0e29 | 1245 | qdict_copy_default(child_options, parent_options, BDRV_OPT_READ_ONLY); |
3f48686f | 1246 | qdict_copy_default(child_options, parent_options, BDRV_OPT_DISCARD); |
f87a0e29 | 1247 | |
41869044 KW |
1248 | /* aio=native doesn't work for cache.direct=off, so disable it for the |
1249 | * temporary snapshot */ | |
1250 | *child_flags &= ~BDRV_O_NATIVE_AIO; | |
b1e6fc08 KW |
1251 | } |
1252 | ||
db95dbba KW |
1253 | static void bdrv_backing_attach(BdrvChild *c) |
1254 | { | |
1255 | BlockDriverState *parent = c->opaque; | |
1256 | BlockDriverState *backing_hd = c->bs; | |
1257 | ||
bdb73476 | 1258 | GLOBAL_STATE_CODE(); |
db95dbba KW |
1259 | assert(!parent->backing_blocker); |
1260 | error_setg(&parent->backing_blocker, | |
1261 | "node is used as backing hd of '%s'", | |
1262 | bdrv_get_device_or_node_name(parent)); | |
1263 | ||
f30c66ba HR |
1264 | bdrv_refresh_filename(backing_hd); |
1265 | ||
db95dbba | 1266 | parent->open_flags &= ~BDRV_O_NO_BACKING; |
db95dbba KW |
1267 | |
1268 | bdrv_op_block_all(backing_hd, parent->backing_blocker); | |
1269 | /* Otherwise we won't be able to commit or stream */ | |
1270 | bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_COMMIT_TARGET, | |
1271 | parent->backing_blocker); | |
1272 | bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_STREAM, | |
1273 | parent->backing_blocker); | |
1274 | /* | |
1275 | * We do backup in 3 ways: | |
1276 | * 1. drive backup | |
1277 | * The target bs is new opened, and the source is top BDS | |
1278 | * 2. blockdev backup | |
1279 | * Both the source and the target are top BDSes. | |
1280 | * 3. internal backup(used for block replication) | |
1281 | * Both the source and the target are backing file | |
1282 | * | |
1283 | * In case 1 and 2, neither the source nor the target is the backing file. | |
1284 | * In case 3, we will block the top BDS, so there is only one block job | |
1285 | * for the top BDS and its backing chain. | |
1286 | */ | |
1287 | bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_SOURCE, | |
1288 | parent->backing_blocker); | |
1289 | bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_TARGET, | |
1290 | parent->backing_blocker); | |
ca2f1234 | 1291 | } |
d736f119 | 1292 | |
db95dbba KW |
1293 | static void bdrv_backing_detach(BdrvChild *c) |
1294 | { | |
1295 | BlockDriverState *parent = c->opaque; | |
1296 | ||
bdb73476 | 1297 | GLOBAL_STATE_CODE(); |
db95dbba KW |
1298 | assert(parent->backing_blocker); |
1299 | bdrv_op_unblock_all(c->bs, parent->backing_blocker); | |
1300 | error_free(parent->backing_blocker); | |
1301 | parent->backing_blocker = NULL; | |
48e08288 | 1302 | } |
d736f119 | 1303 | |
6858eba0 KW |
1304 | static int bdrv_backing_update_filename(BdrvChild *c, BlockDriverState *base, |
1305 | const char *filename, Error **errp) | |
1306 | { | |
1307 | BlockDriverState *parent = c->opaque; | |
e94d3dba | 1308 | bool read_only = bdrv_is_read_only(parent); |
6858eba0 | 1309 | int ret; |
bdb73476 | 1310 | GLOBAL_STATE_CODE(); |
6858eba0 | 1311 | |
e94d3dba AG |
1312 | if (read_only) { |
1313 | ret = bdrv_reopen_set_read_only(parent, false, errp); | |
61f09cea KW |
1314 | if (ret < 0) { |
1315 | return ret; | |
1316 | } | |
1317 | } | |
1318 | ||
6858eba0 | 1319 | ret = bdrv_change_backing_file(parent, filename, |
e54ee1b3 EB |
1320 | base->drv ? base->drv->format_name : "", |
1321 | false); | |
6858eba0 | 1322 | if (ret < 0) { |
64730694 | 1323 | error_setg_errno(errp, -ret, "Could not update backing file link"); |
6858eba0 KW |
1324 | } |
1325 | ||
e94d3dba AG |
1326 | if (read_only) { |
1327 | bdrv_reopen_set_read_only(parent, true, NULL); | |
61f09cea KW |
1328 | } |
1329 | ||
6858eba0 KW |
1330 | return ret; |
1331 | } | |
1332 | ||
fae8bd39 HR |
1333 | /* |
1334 | * Returns the options and flags that a generic child of a BDS should | |
1335 | * get, based on the given options and flags for the parent BDS. | |
1336 | */ | |
00ff7ffd HR |
1337 | static void bdrv_inherited_options(BdrvChildRole role, bool parent_is_format, |
1338 | int *child_flags, QDict *child_options, | |
1339 | int parent_flags, QDict *parent_options) | |
fae8bd39 HR |
1340 | { |
1341 | int flags = parent_flags; | |
bdb73476 | 1342 | GLOBAL_STATE_CODE(); |
fae8bd39 HR |
1343 | |
1344 | /* | |
1345 | * First, decide whether to set, clear, or leave BDRV_O_PROTOCOL. | |
1346 | * Generally, the question to answer is: Should this child be | |
1347 | * format-probed by default? | |
1348 | */ | |
1349 | ||
1350 | /* | |
1351 | * Pure and non-filtered data children of non-format nodes should | |
1352 | * be probed by default (even when the node itself has BDRV_O_PROTOCOL | |
1353 | * set). This only affects a very limited set of drivers (namely | |
1354 | * quorum and blkverify when this comment was written). | |
1355 | * Force-clear BDRV_O_PROTOCOL then. | |
1356 | */ | |
1357 | if (!parent_is_format && | |
1358 | (role & BDRV_CHILD_DATA) && | |
1359 | !(role & (BDRV_CHILD_METADATA | BDRV_CHILD_FILTERED))) | |
1360 | { | |
1361 | flags &= ~BDRV_O_PROTOCOL; | |
1362 | } | |
1363 | ||
1364 | /* | |
1365 | * All children of format nodes (except for COW children) and all | |
1366 | * metadata children in general should never be format-probed. | |
1367 | * Force-set BDRV_O_PROTOCOL then. | |
1368 | */ | |
1369 | if ((parent_is_format && !(role & BDRV_CHILD_COW)) || | |
1370 | (role & BDRV_CHILD_METADATA)) | |
1371 | { | |
1372 | flags |= BDRV_O_PROTOCOL; | |
1373 | } | |
1374 | ||
1375 | /* | |
1376 | * If the cache mode isn't explicitly set, inherit direct and no-flush from | |
1377 | * the parent. | |
1378 | */ | |
1379 | qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_DIRECT); | |
1380 | qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_NO_FLUSH); | |
1381 | qdict_copy_default(child_options, parent_options, BDRV_OPT_FORCE_SHARE); | |
1382 | ||
1383 | if (role & BDRV_CHILD_COW) { | |
1384 | /* backing files are opened read-only by default */ | |
1385 | qdict_set_default_str(child_options, BDRV_OPT_READ_ONLY, "on"); | |
1386 | qdict_set_default_str(child_options, BDRV_OPT_AUTO_READ_ONLY, "off"); | |
1387 | } else { | |
1388 | /* Inherit the read-only option from the parent if it's not set */ | |
1389 | qdict_copy_default(child_options, parent_options, BDRV_OPT_READ_ONLY); | |
1390 | qdict_copy_default(child_options, parent_options, | |
1391 | BDRV_OPT_AUTO_READ_ONLY); | |
1392 | } | |
1393 | ||
1394 | /* | |
1395 | * bdrv_co_pdiscard() respects unmap policy for the parent, so we | |
1396 | * can default to enable it on lower layers regardless of the | |
1397 | * parent option. | |
1398 | */ | |
1399 | qdict_set_default_str(child_options, BDRV_OPT_DISCARD, "unmap"); | |
1400 | ||
1401 | /* Clear flags that only apply to the top layer */ | |
1402 | flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_COPY_ON_READ); | |
1403 | ||
1404 | if (role & BDRV_CHILD_METADATA) { | |
1405 | flags &= ~BDRV_O_NO_IO; | |
1406 | } | |
1407 | if (role & BDRV_CHILD_COW) { | |
1408 | flags &= ~BDRV_O_TEMPORARY; | |
1409 | } | |
1410 | ||
1411 | *child_flags = flags; | |
1412 | } | |
1413 | ||
303de47b | 1414 | static void GRAPH_WRLOCK bdrv_child_cb_attach(BdrvChild *child) |
ca2f1234 HR |
1415 | { |
1416 | BlockDriverState *bs = child->opaque; | |
1417 | ||
3f35f82e | 1418 | assert_bdrv_graph_writable(); |
a225369b | 1419 | QLIST_INSERT_HEAD(&bs->children, child, next); |
5bb04747 VSO |
1420 | if (bs->drv->is_filter || (child->role & BDRV_CHILD_FILTERED)) { |
1421 | /* | |
1422 | * Here we handle filters and block/raw-format.c when it behave like | |
1423 | * filter. They generally have a single PRIMARY child, which is also the | |
1424 | * FILTERED child, and that they may have multiple more children, which | |
1425 | * are neither PRIMARY nor FILTERED. And never we have a COW child here. | |
1426 | * So bs->file will be the PRIMARY child, unless the PRIMARY child goes | |
1427 | * into bs->backing on exceptional cases; and bs->backing will be | |
1428 | * nothing else. | |
1429 | */ | |
1430 | assert(!(child->role & BDRV_CHILD_COW)); | |
1431 | if (child->role & BDRV_CHILD_PRIMARY) { | |
1432 | assert(child->role & BDRV_CHILD_FILTERED); | |
1433 | assert(!bs->backing); | |
1434 | assert(!bs->file); | |
1435 | ||
1436 | if (bs->drv->filtered_child_is_backing) { | |
1437 | bs->backing = child; | |
1438 | } else { | |
1439 | bs->file = child; | |
1440 | } | |
1441 | } else { | |
1442 | assert(!(child->role & BDRV_CHILD_FILTERED)); | |
1443 | } | |
1444 | } else if (child->role & BDRV_CHILD_COW) { | |
1445 | assert(bs->drv->supports_backing); | |
1446 | assert(!(child->role & BDRV_CHILD_PRIMARY)); | |
1447 | assert(!bs->backing); | |
1448 | bs->backing = child; | |
ca2f1234 | 1449 | bdrv_backing_attach(child); |
5bb04747 VSO |
1450 | } else if (child->role & BDRV_CHILD_PRIMARY) { |
1451 | assert(!bs->file); | |
1452 | bs->file = child; | |
ca2f1234 | 1453 | } |
ca2f1234 HR |
1454 | } |
1455 | ||
303de47b | 1456 | static void GRAPH_WRLOCK bdrv_child_cb_detach(BdrvChild *child) |
48e08288 HR |
1457 | { |
1458 | BlockDriverState *bs = child->opaque; | |
1459 | ||
1460 | if (child->role & BDRV_CHILD_COW) { | |
1461 | bdrv_backing_detach(child); | |
1462 | } | |
1463 | ||
3f35f82e | 1464 | assert_bdrv_graph_writable(); |
a225369b | 1465 | QLIST_REMOVE(child, next); |
5bb04747 VSO |
1466 | if (child == bs->backing) { |
1467 | assert(child != bs->file); | |
1468 | bs->backing = NULL; | |
1469 | } else if (child == bs->file) { | |
1470 | bs->file = NULL; | |
1471 | } | |
48e08288 HR |
1472 | } |
1473 | ||
43483550 HR |
1474 | static int bdrv_child_cb_update_filename(BdrvChild *c, BlockDriverState *base, |
1475 | const char *filename, Error **errp) | |
1476 | { | |
1477 | if (c->role & BDRV_CHILD_COW) { | |
1478 | return bdrv_backing_update_filename(c, base, filename, errp); | |
1479 | } | |
1480 | return 0; | |
1481 | } | |
1482 | ||
fb62b588 | 1483 | AioContext *child_of_bds_get_parent_aio_context(BdrvChild *c) |
3ca1f322 VSO |
1484 | { |
1485 | BlockDriverState *bs = c->opaque; | |
384a48fb | 1486 | IO_CODE(); |
3ca1f322 VSO |
1487 | |
1488 | return bdrv_get_aio_context(bs); | |
1489 | } | |
1490 | ||
43483550 HR |
1491 | const BdrvChildClass child_of_bds = { |
1492 | .parent_is_bds = true, | |
1493 | .get_parent_desc = bdrv_child_get_parent_desc, | |
1494 | .inherit_options = bdrv_inherited_options, | |
1495 | .drained_begin = bdrv_child_cb_drained_begin, | |
1496 | .drained_poll = bdrv_child_cb_drained_poll, | |
1497 | .drained_end = bdrv_child_cb_drained_end, | |
1498 | .attach = bdrv_child_cb_attach, | |
1499 | .detach = bdrv_child_cb_detach, | |
1500 | .inactivate = bdrv_child_cb_inactivate, | |
27633e74 | 1501 | .change_aio_ctx = bdrv_child_cb_change_aio_ctx, |
43483550 | 1502 | .update_filename = bdrv_child_cb_update_filename, |
fb62b588 | 1503 | .get_parent_aio_context = child_of_bds_get_parent_aio_context, |
43483550 HR |
1504 | }; |
1505 | ||
3ca1f322 VSO |
1506 | AioContext *bdrv_child_get_parent_aio_context(BdrvChild *c) |
1507 | { | |
d5f8d79c | 1508 | IO_CODE(); |
3ca1f322 VSO |
1509 | return c->klass->get_parent_aio_context(c); |
1510 | } | |
1511 | ||
7b272452 KW |
1512 | static int bdrv_open_flags(BlockDriverState *bs, int flags) |
1513 | { | |
61de4c68 | 1514 | int open_flags = flags; |
bdb73476 | 1515 | GLOBAL_STATE_CODE(); |
7b272452 KW |
1516 | |
1517 | /* | |
1518 | * Clear flags that are internal to the block layer before opening the | |
1519 | * image. | |
1520 | */ | |
20cca275 | 1521 | open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_PROTOCOL); |
7b272452 | 1522 | |
7b272452 KW |
1523 | return open_flags; |
1524 | } | |
1525 | ||
91a097e7 KW |
1526 | static void update_flags_from_options(int *flags, QemuOpts *opts) |
1527 | { | |
bdb73476 EGE |
1528 | GLOBAL_STATE_CODE(); |
1529 | ||
2a3d4331 | 1530 | *flags &= ~(BDRV_O_CACHE_MASK | BDRV_O_RDWR | BDRV_O_AUTO_RDONLY); |
91a097e7 | 1531 | |
57f9db9a | 1532 | if (qemu_opt_get_bool_del(opts, BDRV_OPT_CACHE_NO_FLUSH, false)) { |
91a097e7 KW |
1533 | *flags |= BDRV_O_NO_FLUSH; |
1534 | } | |
1535 | ||
57f9db9a | 1536 | if (qemu_opt_get_bool_del(opts, BDRV_OPT_CACHE_DIRECT, false)) { |
91a097e7 KW |
1537 | *flags |= BDRV_O_NOCACHE; |
1538 | } | |
f87a0e29 | 1539 | |
57f9db9a | 1540 | if (!qemu_opt_get_bool_del(opts, BDRV_OPT_READ_ONLY, false)) { |
f87a0e29 AG |
1541 | *flags |= BDRV_O_RDWR; |
1542 | } | |
1543 | ||
e35bdc12 KW |
1544 | if (qemu_opt_get_bool_del(opts, BDRV_OPT_AUTO_READ_ONLY, false)) { |
1545 | *flags |= BDRV_O_AUTO_RDONLY; | |
1546 | } | |
91a097e7 KW |
1547 | } |
1548 | ||
1549 | static void update_options_from_flags(QDict *options, int flags) | |
1550 | { | |
bdb73476 | 1551 | GLOBAL_STATE_CODE(); |
91a097e7 | 1552 | if (!qdict_haskey(options, BDRV_OPT_CACHE_DIRECT)) { |
46f5ac20 | 1553 | qdict_put_bool(options, BDRV_OPT_CACHE_DIRECT, flags & BDRV_O_NOCACHE); |
91a097e7 KW |
1554 | } |
1555 | if (!qdict_haskey(options, BDRV_OPT_CACHE_NO_FLUSH)) { | |
46f5ac20 EB |
1556 | qdict_put_bool(options, BDRV_OPT_CACHE_NO_FLUSH, |
1557 | flags & BDRV_O_NO_FLUSH); | |
91a097e7 | 1558 | } |
f87a0e29 | 1559 | if (!qdict_haskey(options, BDRV_OPT_READ_ONLY)) { |
46f5ac20 | 1560 | qdict_put_bool(options, BDRV_OPT_READ_ONLY, !(flags & BDRV_O_RDWR)); |
f87a0e29 | 1561 | } |
e35bdc12 KW |
1562 | if (!qdict_haskey(options, BDRV_OPT_AUTO_READ_ONLY)) { |
1563 | qdict_put_bool(options, BDRV_OPT_AUTO_READ_ONLY, | |
1564 | flags & BDRV_O_AUTO_RDONLY); | |
1565 | } | |
91a097e7 KW |
1566 | } |
1567 | ||
636ea370 KW |
1568 | static void bdrv_assign_node_name(BlockDriverState *bs, |
1569 | const char *node_name, | |
1570 | Error **errp) | |
6913c0c2 | 1571 | { |
15489c76 | 1572 | char *gen_node_name = NULL; |
bdb73476 | 1573 | GLOBAL_STATE_CODE(); |
6913c0c2 | 1574 | |
15489c76 JC |
1575 | if (!node_name) { |
1576 | node_name = gen_node_name = id_generate(ID_BLOCK); | |
1577 | } else if (!id_wellformed(node_name)) { | |
1578 | /* | |
1579 | * Check for empty string or invalid characters, but not if it is | |
1580 | * generated (generated names use characters not available to the user) | |
1581 | */ | |
785ec4b1 | 1582 | error_setg(errp, "Invalid node-name: '%s'", node_name); |
636ea370 | 1583 | return; |
6913c0c2 BC |
1584 | } |
1585 | ||
0c5e94ee | 1586 | /* takes care of avoiding namespaces collisions */ |
7f06d47e | 1587 | if (blk_by_name(node_name)) { |
0c5e94ee BC |
1588 | error_setg(errp, "node-name=%s is conflicting with a device id", |
1589 | node_name); | |
15489c76 | 1590 | goto out; |
0c5e94ee BC |
1591 | } |
1592 | ||
6913c0c2 BC |
1593 | /* takes care of avoiding duplicates node names */ |
1594 | if (bdrv_find_node(node_name)) { | |
785ec4b1 | 1595 | error_setg(errp, "Duplicate nodes with node-name='%s'", node_name); |
15489c76 | 1596 | goto out; |
6913c0c2 BC |
1597 | } |
1598 | ||
824808dd KW |
1599 | /* Make sure that the node name isn't truncated */ |
1600 | if (strlen(node_name) >= sizeof(bs->node_name)) { | |
1601 | error_setg(errp, "Node name too long"); | |
1602 | goto out; | |
1603 | } | |
1604 | ||
6913c0c2 BC |
1605 | /* copy node name into the bs and insert it into the graph list */ |
1606 | pstrcpy(bs->node_name, sizeof(bs->node_name), node_name); | |
1607 | QTAILQ_INSERT_TAIL(&graph_bdrv_states, bs, node_list); | |
15489c76 JC |
1608 | out: |
1609 | g_free(gen_node_name); | |
6913c0c2 BC |
1610 | } |
1611 | ||
c86422c5 EGE |
1612 | /* |
1613 | * The caller must always hold @bs AioContext lock, because this function calls | |
1614 | * bdrv_refresh_total_sectors() which polls when called from non-coroutine | |
1615 | * context. | |
1616 | */ | |
1a30b0f5 KW |
1617 | static int no_coroutine_fn GRAPH_UNLOCKED |
1618 | bdrv_open_driver(BlockDriverState *bs, BlockDriver *drv, const char *node_name, | |
1619 | QDict *options, int open_flags, Error **errp) | |
01a56501 | 1620 | { |
8dc8a60c | 1621 | AioContext *ctx; |
01a56501 | 1622 | Error *local_err = NULL; |
0f12264e | 1623 | int i, ret; |
da359909 | 1624 | GLOBAL_STATE_CODE(); |
01a56501 KW |
1625 | |
1626 | bdrv_assign_node_name(bs, node_name, &local_err); | |
1627 | if (local_err) { | |
1628 | error_propagate(errp, local_err); | |
1629 | return -EINVAL; | |
1630 | } | |
1631 | ||
1632 | bs->drv = drv; | |
1633 | bs->opaque = g_malloc0(drv->instance_size); | |
1634 | ||
1635 | if (drv->bdrv_file_open) { | |
1636 | assert(!drv->bdrv_needs_filename || bs->filename[0]); | |
1637 | ret = drv->bdrv_file_open(bs, options, open_flags, &local_err); | |
680c7f96 | 1638 | } else if (drv->bdrv_open) { |
01a56501 | 1639 | ret = drv->bdrv_open(bs, options, open_flags, &local_err); |
680c7f96 KW |
1640 | } else { |
1641 | ret = 0; | |
01a56501 KW |
1642 | } |
1643 | ||
1644 | if (ret < 0) { | |
1645 | if (local_err) { | |
1646 | error_propagate(errp, local_err); | |
1647 | } else if (bs->filename[0]) { | |
1648 | error_setg_errno(errp, -ret, "Could not open '%s'", bs->filename); | |
1649 | } else { | |
1650 | error_setg_errno(errp, -ret, "Could not open image"); | |
1651 | } | |
180ca19a | 1652 | goto open_failed; |
01a56501 KW |
1653 | } |
1654 | ||
e8b65355 SH |
1655 | assert(!(bs->supported_read_flags & ~BDRV_REQ_MASK)); |
1656 | assert(!(bs->supported_write_flags & ~BDRV_REQ_MASK)); | |
1657 | ||
1658 | /* | |
1659 | * Always allow the BDRV_REQ_REGISTERED_BUF optimization hint. This saves | |
1660 | * drivers that pass read/write requests through to a child the trouble of | |
1661 | * declaring support explicitly. | |
1662 | * | |
1663 | * Drivers must not propagate this flag accidentally when they initiate I/O | |
1664 | * to a bounce buffer. That case should be rare though. | |
1665 | */ | |
1666 | bs->supported_read_flags |= BDRV_REQ_REGISTERED_BUF; | |
1667 | bs->supported_write_flags |= BDRV_REQ_REGISTERED_BUF; | |
1668 | ||
8dc8a60c KW |
1669 | /* Get the context after .bdrv_open, it can change the context */ |
1670 | ctx = bdrv_get_aio_context(bs); | |
1671 | aio_context_acquire(ctx); | |
1672 | ||
c057960c | 1673 | ret = bdrv_refresh_total_sectors(bs, bs->total_sectors); |
01a56501 KW |
1674 | if (ret < 0) { |
1675 | error_setg_errno(errp, -ret, "Could not refresh total sector count"); | |
8dc8a60c | 1676 | aio_context_release(ctx); |
180ca19a | 1677 | return ret; |
01a56501 KW |
1678 | } |
1679 | ||
e19b157f | 1680 | bdrv_graph_rdlock_main_loop(); |
1e4c797c | 1681 | bdrv_refresh_limits(bs, NULL, &local_err); |
e19b157f | 1682 | bdrv_graph_rdunlock_main_loop(); |
8dc8a60c | 1683 | aio_context_release(ctx); |
e19b157f | 1684 | |
01a56501 KW |
1685 | if (local_err) { |
1686 | error_propagate(errp, local_err); | |
180ca19a | 1687 | return -EINVAL; |
01a56501 KW |
1688 | } |
1689 | ||
1690 | assert(bdrv_opt_mem_align(bs) != 0); | |
1691 | assert(bdrv_min_mem_align(bs) != 0); | |
1692 | assert(is_power_of_2(bs->bl.request_alignment)); | |
1693 | ||
0f12264e | 1694 | for (i = 0; i < bs->quiesce_counter; i++) { |
5e8ac217 KW |
1695 | if (drv->bdrv_drain_begin) { |
1696 | drv->bdrv_drain_begin(bs); | |
0f12264e KW |
1697 | } |
1698 | } | |
1699 | ||
01a56501 | 1700 | return 0; |
180ca19a MP |
1701 | open_failed: |
1702 | bs->drv = NULL; | |
1703 | if (bs->file != NULL) { | |
32a8aba3 | 1704 | bdrv_graph_wrlock(NULL); |
180ca19a | 1705 | bdrv_unref_child(bs, bs->file); |
32a8aba3 | 1706 | bdrv_graph_wrunlock(); |
5bb04747 | 1707 | assert(!bs->file); |
180ca19a | 1708 | } |
01a56501 KW |
1709 | g_free(bs->opaque); |
1710 | bs->opaque = NULL; | |
01a56501 KW |
1711 | return ret; |
1712 | } | |
1713 | ||
621d1737 VSO |
1714 | /* |
1715 | * Create and open a block node. | |
1716 | * | |
1717 | * @options is a QDict of options to pass to the block drivers, or NULL for an | |
1718 | * empty set of options. The reference to the QDict belongs to the block layer | |
1719 | * after the call (even on failure), so if the caller intends to reuse the | |
1720 | * dictionary, it needs to use qobject_ref() before calling bdrv_open. | |
1721 | */ | |
1722 | BlockDriverState *bdrv_new_open_driver_opts(BlockDriver *drv, | |
1723 | const char *node_name, | |
1724 | QDict *options, int flags, | |
1725 | Error **errp) | |
680c7f96 KW |
1726 | { |
1727 | BlockDriverState *bs; | |
1728 | int ret; | |
1729 | ||
f791bf7f EGE |
1730 | GLOBAL_STATE_CODE(); |
1731 | ||
680c7f96 KW |
1732 | bs = bdrv_new(); |
1733 | bs->open_flags = flags; | |
621d1737 VSO |
1734 | bs->options = options ?: qdict_new(); |
1735 | bs->explicit_options = qdict_clone_shallow(bs->options); | |
680c7f96 KW |
1736 | bs->opaque = NULL; |
1737 | ||
1738 | update_options_from_flags(bs->options, flags); | |
1739 | ||
1740 | ret = bdrv_open_driver(bs, drv, node_name, bs->options, flags, errp); | |
1741 | if (ret < 0) { | |
cb3e7f08 | 1742 | qobject_unref(bs->explicit_options); |
180ca19a | 1743 | bs->explicit_options = NULL; |
cb3e7f08 | 1744 | qobject_unref(bs->options); |
180ca19a | 1745 | bs->options = NULL; |
680c7f96 KW |
1746 | bdrv_unref(bs); |
1747 | return NULL; | |
1748 | } | |
1749 | ||
1750 | return bs; | |
1751 | } | |
1752 | ||
621d1737 VSO |
1753 | /* Create and open a block node. */ |
1754 | BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, | |
1755 | int flags, Error **errp) | |
1756 | { | |
f791bf7f | 1757 | GLOBAL_STATE_CODE(); |
621d1737 VSO |
1758 | return bdrv_new_open_driver_opts(drv, node_name, NULL, flags, errp); |
1759 | } | |
1760 | ||
c5f3014b | 1761 | QemuOptsList bdrv_runtime_opts = { |
18edf289 KW |
1762 | .name = "bdrv_common", |
1763 | .head = QTAILQ_HEAD_INITIALIZER(bdrv_runtime_opts.head), | |
1764 | .desc = { | |
1765 | { | |
1766 | .name = "node-name", | |
1767 | .type = QEMU_OPT_STRING, | |
1768 | .help = "Node name of the block device node", | |
1769 | }, | |
62392ebb KW |
1770 | { |
1771 | .name = "driver", | |
1772 | .type = QEMU_OPT_STRING, | |
1773 | .help = "Block driver to use for the node", | |
1774 | }, | |
91a097e7 KW |
1775 | { |
1776 | .name = BDRV_OPT_CACHE_DIRECT, | |
1777 | .type = QEMU_OPT_BOOL, | |
1778 | .help = "Bypass software writeback cache on the host", | |
1779 | }, | |
1780 | { | |
1781 | .name = BDRV_OPT_CACHE_NO_FLUSH, | |
1782 | .type = QEMU_OPT_BOOL, | |
1783 | .help = "Ignore flush requests", | |
1784 | }, | |
f87a0e29 AG |
1785 | { |
1786 | .name = BDRV_OPT_READ_ONLY, | |
1787 | .type = QEMU_OPT_BOOL, | |
1788 | .help = "Node is opened in read-only mode", | |
1789 | }, | |
e35bdc12 KW |
1790 | { |
1791 | .name = BDRV_OPT_AUTO_READ_ONLY, | |
1792 | .type = QEMU_OPT_BOOL, | |
1793 | .help = "Node can become read-only if opening read-write fails", | |
1794 | }, | |
692e01a2 KW |
1795 | { |
1796 | .name = "detect-zeroes", | |
1797 | .type = QEMU_OPT_STRING, | |
1798 | .help = "try to optimize zero writes (off, on, unmap)", | |
1799 | }, | |
818584a4 | 1800 | { |
415bbca8 | 1801 | .name = BDRV_OPT_DISCARD, |
818584a4 KW |
1802 | .type = QEMU_OPT_STRING, |
1803 | .help = "discard operation (ignore/off, unmap/on)", | |
1804 | }, | |
5a9347c6 FZ |
1805 | { |
1806 | .name = BDRV_OPT_FORCE_SHARE, | |
1807 | .type = QEMU_OPT_BOOL, | |
1808 | .help = "always accept other writers (default: off)", | |
1809 | }, | |
18edf289 KW |
1810 | { /* end of list */ } |
1811 | }, | |
1812 | }; | |
1813 | ||
5a5e7f8c ML |
1814 | QemuOptsList bdrv_create_opts_simple = { |
1815 | .name = "simple-create-opts", | |
1816 | .head = QTAILQ_HEAD_INITIALIZER(bdrv_create_opts_simple.head), | |
fd17146c HR |
1817 | .desc = { |
1818 | { | |
1819 | .name = BLOCK_OPT_SIZE, | |
1820 | .type = QEMU_OPT_SIZE, | |
1821 | .help = "Virtual disk size" | |
1822 | }, | |
1823 | { | |
1824 | .name = BLOCK_OPT_PREALLOC, | |
1825 | .type = QEMU_OPT_STRING, | |
1826 | .help = "Preallocation mode (allowed values: off)" | |
1827 | }, | |
1828 | { /* end of list */ } | |
1829 | } | |
1830 | }; | |
1831 | ||
57915332 KW |
1832 | /* |
1833 | * Common part for opening disk images and files | |
b6ad491a KW |
1834 | * |
1835 | * Removes all processed options from *options. | |
57915332 | 1836 | */ |
5696c6e3 | 1837 | static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file, |
82dc8b41 | 1838 | QDict *options, Error **errp) |
57915332 KW |
1839 | { |
1840 | int ret, open_flags; | |
035fccdf | 1841 | const char *filename; |
62392ebb | 1842 | const char *driver_name = NULL; |
6913c0c2 | 1843 | const char *node_name = NULL; |
818584a4 | 1844 | const char *discard; |
18edf289 | 1845 | QemuOpts *opts; |
62392ebb | 1846 | BlockDriver *drv; |
34b5d2c6 | 1847 | Error *local_err = NULL; |
307261b2 | 1848 | bool ro; |
57915332 | 1849 | |
6405875c | 1850 | assert(bs->file == NULL); |
707ff828 | 1851 | assert(options != NULL && bs->options != options); |
bdb73476 | 1852 | GLOBAL_STATE_CODE(); |
57915332 | 1853 | |
62392ebb | 1854 | opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort); |
af175e85 | 1855 | if (!qemu_opts_absorb_qdict(opts, options, errp)) { |
62392ebb KW |
1856 | ret = -EINVAL; |
1857 | goto fail_opts; | |
1858 | } | |
1859 | ||
9b7e8691 AG |
1860 | update_flags_from_options(&bs->open_flags, opts); |
1861 | ||
62392ebb KW |
1862 | driver_name = qemu_opt_get(opts, "driver"); |
1863 | drv = bdrv_find_format(driver_name); | |
1864 | assert(drv != NULL); | |
1865 | ||
5a9347c6 FZ |
1866 | bs->force_share = qemu_opt_get_bool(opts, BDRV_OPT_FORCE_SHARE, false); |
1867 | ||
1868 | if (bs->force_share && (bs->open_flags & BDRV_O_RDWR)) { | |
1869 | error_setg(errp, | |
1870 | BDRV_OPT_FORCE_SHARE | |
1871 | "=on can only be used with read-only images"); | |
1872 | ret = -EINVAL; | |
1873 | goto fail_opts; | |
1874 | } | |
1875 | ||
45673671 | 1876 | if (file != NULL) { |
f30c66ba | 1877 | bdrv_refresh_filename(blk_bs(file)); |
5696c6e3 | 1878 | filename = blk_bs(file)->filename; |
45673671 | 1879 | } else { |
129c7d1c MA |
1880 | /* |
1881 | * Caution: while qdict_get_try_str() is fine, getting | |
1882 | * non-string types would require more care. When @options | |
1883 | * come from -blockdev or blockdev_add, its members are typed | |
1884 | * according to the QAPI schema, but when they come from | |
1885 | * -drive, they're all QString. | |
1886 | */ | |
45673671 KW |
1887 | filename = qdict_get_try_str(options, "filename"); |
1888 | } | |
1889 | ||
4a008240 | 1890 | if (drv->bdrv_needs_filename && (!filename || !filename[0])) { |
765003db KW |
1891 | error_setg(errp, "The '%s' block driver requires a file name", |
1892 | drv->format_name); | |
18edf289 KW |
1893 | ret = -EINVAL; |
1894 | goto fail_opts; | |
6913c0c2 | 1895 | } |
6913c0c2 | 1896 | |
82dc8b41 KW |
1897 | trace_bdrv_open_common(bs, filename ?: "", bs->open_flags, |
1898 | drv->format_name); | |
62392ebb | 1899 | |
307261b2 VSO |
1900 | ro = bdrv_is_read_only(bs); |
1901 | ||
1902 | if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, ro)) { | |
1903 | if (!ro && bdrv_is_whitelisted(drv, true)) { | |
8be25de6 KW |
1904 | ret = bdrv_apply_auto_read_only(bs, NULL, NULL); |
1905 | } else { | |
1906 | ret = -ENOTSUP; | |
1907 | } | |
1908 | if (ret < 0) { | |
1909 | error_setg(errp, | |
307261b2 | 1910 | !ro && bdrv_is_whitelisted(drv, true) |
8be25de6 KW |
1911 | ? "Driver '%s' can only be used for read-only devices" |
1912 | : "Driver '%s' is not whitelisted", | |
1913 | drv->format_name); | |
1914 | goto fail_opts; | |
1915 | } | |
b64ec4e4 | 1916 | } |
57915332 | 1917 | |
d3faa13e | 1918 | /* bdrv_new() and bdrv_close() make it so */ |
d73415a3 | 1919 | assert(qatomic_read(&bs->copy_on_read) == 0); |
d3faa13e | 1920 | |
82dc8b41 | 1921 | if (bs->open_flags & BDRV_O_COPY_ON_READ) { |
307261b2 | 1922 | if (!ro) { |
0ebd24e0 KW |
1923 | bdrv_enable_copy_on_read(bs); |
1924 | } else { | |
1925 | error_setg(errp, "Can't use copy-on-read on read-only device"); | |
18edf289 KW |
1926 | ret = -EINVAL; |
1927 | goto fail_opts; | |
0ebd24e0 | 1928 | } |
53fec9d3 SH |
1929 | } |
1930 | ||
415bbca8 | 1931 | discard = qemu_opt_get(opts, BDRV_OPT_DISCARD); |
818584a4 KW |
1932 | if (discard != NULL) { |
1933 | if (bdrv_parse_discard_flags(discard, &bs->open_flags) != 0) { | |
1934 | error_setg(errp, "Invalid discard option"); | |
1935 | ret = -EINVAL; | |
1936 | goto fail_opts; | |
1937 | } | |
1938 | } | |
1939 | ||
543770bd AG |
1940 | bs->detect_zeroes = |
1941 | bdrv_parse_detect_zeroes(opts, bs->open_flags, &local_err); | |
1942 | if (local_err) { | |
1943 | error_propagate(errp, local_err); | |
1944 | ret = -EINVAL; | |
1945 | goto fail_opts; | |
692e01a2 KW |
1946 | } |
1947 | ||
c2ad1b0c KW |
1948 | if (filename != NULL) { |
1949 | pstrcpy(bs->filename, sizeof(bs->filename), filename); | |
1950 | } else { | |
1951 | bs->filename[0] = '\0'; | |
1952 | } | |
91af7014 | 1953 | pstrcpy(bs->exact_filename, sizeof(bs->exact_filename), bs->filename); |
57915332 | 1954 | |
66f82cee | 1955 | /* Open the image, either directly or using a protocol */ |
82dc8b41 | 1956 | open_flags = bdrv_open_flags(bs, bs->open_flags); |
01a56501 | 1957 | node_name = qemu_opt_get(opts, "node-name"); |
57915332 | 1958 | |
01a56501 KW |
1959 | assert(!drv->bdrv_file_open || file == NULL); |
1960 | ret = bdrv_open_driver(bs, drv, node_name, options, open_flags, errp); | |
51762288 | 1961 | if (ret < 0) { |
01a56501 | 1962 | goto fail_opts; |
3baca891 KW |
1963 | } |
1964 | ||
18edf289 | 1965 | qemu_opts_del(opts); |
57915332 KW |
1966 | return 0; |
1967 | ||
18edf289 KW |
1968 | fail_opts: |
1969 | qemu_opts_del(opts); | |
57915332 KW |
1970 | return ret; |
1971 | } | |
1972 | ||
5e5c4f63 KW |
1973 | static QDict *parse_json_filename(const char *filename, Error **errp) |
1974 | { | |
1975 | QObject *options_obj; | |
1976 | QDict *options; | |
1977 | int ret; | |
bdb73476 | 1978 | GLOBAL_STATE_CODE(); |
5e5c4f63 KW |
1979 | |
1980 | ret = strstart(filename, "json:", &filename); | |
1981 | assert(ret); | |
1982 | ||
5577fff7 | 1983 | options_obj = qobject_from_json(filename, errp); |
5e5c4f63 | 1984 | if (!options_obj) { |
5577fff7 | 1985 | error_prepend(errp, "Could not parse the JSON options: "); |
5e5c4f63 KW |
1986 | return NULL; |
1987 | } | |
1988 | ||
7dc847eb | 1989 | options = qobject_to(QDict, options_obj); |
ca6b6e1e | 1990 | if (!options) { |
cb3e7f08 | 1991 | qobject_unref(options_obj); |
5e5c4f63 KW |
1992 | error_setg(errp, "Invalid JSON object given"); |
1993 | return NULL; | |
1994 | } | |
1995 | ||
5e5c4f63 KW |
1996 | qdict_flatten(options); |
1997 | ||
1998 | return options; | |
1999 | } | |
2000 | ||
de3b53f0 KW |
2001 | static void parse_json_protocol(QDict *options, const char **pfilename, |
2002 | Error **errp) | |
2003 | { | |
2004 | QDict *json_options; | |
2005 | Error *local_err = NULL; | |
bdb73476 | 2006 | GLOBAL_STATE_CODE(); |
de3b53f0 KW |
2007 | |
2008 | /* Parse json: pseudo-protocol */ | |
2009 | if (!*pfilename || !g_str_has_prefix(*pfilename, "json:")) { | |
2010 | return; | |
2011 | } | |
2012 | ||
2013 | json_options = parse_json_filename(*pfilename, &local_err); | |
2014 | if (local_err) { | |
2015 | error_propagate(errp, local_err); | |
2016 | return; | |
2017 | } | |
2018 | ||
2019 | /* Options given in the filename have lower priority than options | |
2020 | * specified directly */ | |
2021 | qdict_join(options, json_options, false); | |
cb3e7f08 | 2022 | qobject_unref(json_options); |
de3b53f0 KW |
2023 | *pfilename = NULL; |
2024 | } | |
2025 | ||
b6ce07aa | 2026 | /* |
f54120ff KW |
2027 | * Fills in default options for opening images and converts the legacy |
2028 | * filename/flags pair to option QDict entries. | |
53a29513 HR |
2029 | * The BDRV_O_PROTOCOL flag in *flags will be set or cleared accordingly if a |
2030 | * block driver has been specified explicitly. | |
b6ce07aa | 2031 | */ |
de3b53f0 | 2032 | static int bdrv_fill_options(QDict **options, const char *filename, |
053e1578 | 2033 | int *flags, Error **errp) |
ea2384d3 | 2034 | { |
c2ad1b0c | 2035 | const char *drvname; |
53a29513 | 2036 | bool protocol = *flags & BDRV_O_PROTOCOL; |
e3fa4bfa | 2037 | bool parse_filename = false; |
053e1578 | 2038 | BlockDriver *drv = NULL; |
34b5d2c6 | 2039 | Error *local_err = NULL; |
83f64091 | 2040 | |
da359909 EGE |
2041 | GLOBAL_STATE_CODE(); |
2042 | ||
129c7d1c MA |
2043 | /* |
2044 | * Caution: while qdict_get_try_str() is fine, getting non-string | |
2045 | * types would require more care. When @options come from | |
2046 | * -blockdev or blockdev_add, its members are typed according to | |
2047 | * the QAPI schema, but when they come from -drive, they're all | |
2048 | * QString. | |
2049 | */ | |
53a29513 | 2050 | drvname = qdict_get_try_str(*options, "driver"); |
053e1578 HR |
2051 | if (drvname) { |
2052 | drv = bdrv_find_format(drvname); | |
2053 | if (!drv) { | |
2054 | error_setg(errp, "Unknown driver '%s'", drvname); | |
2055 | return -ENOENT; | |
2056 | } | |
2057 | /* If the user has explicitly specified the driver, this choice should | |
2058 | * override the BDRV_O_PROTOCOL flag */ | |
2059 | protocol = drv->bdrv_file_open; | |
53a29513 HR |
2060 | } |
2061 | ||
2062 | if (protocol) { | |
2063 | *flags |= BDRV_O_PROTOCOL; | |
2064 | } else { | |
2065 | *flags &= ~BDRV_O_PROTOCOL; | |
2066 | } | |
2067 | ||
91a097e7 KW |
2068 | /* Translate cache options from flags into options */ |
2069 | update_options_from_flags(*options, *flags); | |
2070 | ||
035fccdf | 2071 | /* Fetch the file name from the options QDict if necessary */ |
17b005f1 | 2072 | if (protocol && filename) { |
f54120ff | 2073 | if (!qdict_haskey(*options, "filename")) { |
46f5ac20 | 2074 | qdict_put_str(*options, "filename", filename); |
f54120ff KW |
2075 | parse_filename = true; |
2076 | } else { | |
2077 | error_setg(errp, "Can't specify 'file' and 'filename' options at " | |
2078 | "the same time"); | |
2079 | return -EINVAL; | |
2080 | } | |
035fccdf KW |
2081 | } |
2082 | ||
c2ad1b0c | 2083 | /* Find the right block driver */ |
129c7d1c | 2084 | /* See cautionary note on accessing @options above */ |
f54120ff | 2085 | filename = qdict_get_try_str(*options, "filename"); |
f54120ff | 2086 | |
053e1578 HR |
2087 | if (!drvname && protocol) { |
2088 | if (filename) { | |
2089 | drv = bdrv_find_protocol(filename, parse_filename, errp); | |
17b005f1 | 2090 | if (!drv) { |
053e1578 | 2091 | return -EINVAL; |
17b005f1 | 2092 | } |
053e1578 HR |
2093 | |
2094 | drvname = drv->format_name; | |
46f5ac20 | 2095 | qdict_put_str(*options, "driver", drvname); |
053e1578 HR |
2096 | } else { |
2097 | error_setg(errp, "Must specify either driver or file"); | |
2098 | return -EINVAL; | |
98289620 | 2099 | } |
c2ad1b0c KW |
2100 | } |
2101 | ||
17b005f1 | 2102 | assert(drv || !protocol); |
c2ad1b0c | 2103 | |
f54120ff | 2104 | /* Driver-specific filename parsing */ |
17b005f1 | 2105 | if (drv && drv->bdrv_parse_filename && parse_filename) { |
5acd9d81 | 2106 | drv->bdrv_parse_filename(filename, *options, &local_err); |
84d18f06 | 2107 | if (local_err) { |
34b5d2c6 | 2108 | error_propagate(errp, local_err); |
f54120ff | 2109 | return -EINVAL; |
6963a30d | 2110 | } |
cd5d031e HR |
2111 | |
2112 | if (!drv->bdrv_needs_filename) { | |
2113 | qdict_del(*options, "filename"); | |
cd5d031e | 2114 | } |
6963a30d KW |
2115 | } |
2116 | ||
f54120ff KW |
2117 | return 0; |
2118 | } | |
2119 | ||
148eb13c KW |
2120 | typedef struct BlockReopenQueueEntry { |
2121 | bool prepared; | |
2122 | BDRVReopenState state; | |
859443b0 | 2123 | QTAILQ_ENTRY(BlockReopenQueueEntry) entry; |
148eb13c KW |
2124 | } BlockReopenQueueEntry; |
2125 | ||
2126 | /* | |
2127 | * Return the flags that @bs will have after the reopens in @q have | |
2128 | * successfully completed. If @q is NULL (or @bs is not contained in @q), | |
2129 | * return the current flags. | |
2130 | */ | |
2131 | static int bdrv_reopen_get_flags(BlockReopenQueue *q, BlockDriverState *bs) | |
2132 | { | |
2133 | BlockReopenQueueEntry *entry; | |
2134 | ||
2135 | if (q != NULL) { | |
859443b0 | 2136 | QTAILQ_FOREACH(entry, q, entry) { |
148eb13c KW |
2137 | if (entry->state.bs == bs) { |
2138 | return entry->state.flags; | |
2139 | } | |
2140 | } | |
2141 | } | |
2142 | ||
2143 | return bs->open_flags; | |
2144 | } | |
2145 | ||
2146 | /* Returns whether the image file can be written to after the reopen queue @q | |
2147 | * has been successfully applied, or right now if @q is NULL. */ | |
cc022140 HR |
2148 | static bool bdrv_is_writable_after_reopen(BlockDriverState *bs, |
2149 | BlockReopenQueue *q) | |
148eb13c KW |
2150 | { |
2151 | int flags = bdrv_reopen_get_flags(q, bs); | |
2152 | ||
2153 | return (flags & (BDRV_O_RDWR | BDRV_O_INACTIVE)) == BDRV_O_RDWR; | |
2154 | } | |
2155 | ||
cc022140 HR |
2156 | /* |
2157 | * Return whether the BDS can be written to. This is not necessarily | |
2158 | * the same as !bdrv_is_read_only(bs), as inactivated images may not | |
2159 | * be written to but do not count as read-only images. | |
2160 | */ | |
2161 | bool bdrv_is_writable(BlockDriverState *bs) | |
2162 | { | |
384a48fb | 2163 | IO_CODE(); |
cc022140 HR |
2164 | return bdrv_is_writable_after_reopen(bs, NULL); |
2165 | } | |
2166 | ||
3bf416ba VSO |
2167 | static char *bdrv_child_user_desc(BdrvChild *c) |
2168 | { | |
f0c28327 | 2169 | GLOBAL_STATE_CODE(); |
da261b69 | 2170 | return c->klass->get_parent_desc(c); |
3bf416ba VSO |
2171 | } |
2172 | ||
30ebb9aa VSO |
2173 | /* |
2174 | * Check that @a allows everything that @b needs. @a and @b must reference same | |
2175 | * child node. | |
2176 | */ | |
3bf416ba VSO |
2177 | static bool bdrv_a_allow_b(BdrvChild *a, BdrvChild *b, Error **errp) |
2178 | { | |
30ebb9aa VSO |
2179 | const char *child_bs_name; |
2180 | g_autofree char *a_user = NULL; | |
2181 | g_autofree char *b_user = NULL; | |
2182 | g_autofree char *perms = NULL; | |
2183 | ||
2184 | assert(a->bs); | |
2185 | assert(a->bs == b->bs); | |
862fded9 | 2186 | GLOBAL_STATE_CODE(); |
3bf416ba VSO |
2187 | |
2188 | if ((b->perm & a->shared_perm) == b->perm) { | |
2189 | return true; | |
2190 | } | |
2191 | ||
30ebb9aa VSO |
2192 | child_bs_name = bdrv_get_node_name(b->bs); |
2193 | a_user = bdrv_child_user_desc(a); | |
2194 | b_user = bdrv_child_user_desc(b); | |
2195 | perms = bdrv_perm_names(b->perm & ~a->shared_perm); | |
2196 | ||
2197 | error_setg(errp, "Permission conflict on node '%s': permissions '%s' are " | |
2198 | "both required by %s (uses node '%s' as '%s' child) and " | |
2199 | "unshared by %s (uses node '%s' as '%s' child).", | |
2200 | child_bs_name, perms, | |
2201 | b_user, child_bs_name, b->name, | |
2202 | a_user, child_bs_name, a->name); | |
3bf416ba VSO |
2203 | |
2204 | return false; | |
2205 | } | |
2206 | ||
3804e3cf KW |
2207 | static bool GRAPH_RDLOCK |
2208 | bdrv_parent_perms_conflict(BlockDriverState *bs, Error **errp) | |
3bf416ba VSO |
2209 | { |
2210 | BdrvChild *a, *b; | |
862fded9 | 2211 | GLOBAL_STATE_CODE(); |
3bf416ba VSO |
2212 | |
2213 | /* | |
2214 | * During the loop we'll look at each pair twice. That's correct because | |
2215 | * bdrv_a_allow_b() is asymmetric and we should check each pair in both | |
2216 | * directions. | |
2217 | */ | |
2218 | QLIST_FOREACH(a, &bs->parents, next_parent) { | |
2219 | QLIST_FOREACH(b, &bs->parents, next_parent) { | |
9397c14f | 2220 | if (a == b) { |
3bf416ba VSO |
2221 | continue; |
2222 | } | |
2223 | ||
2224 | if (!bdrv_a_allow_b(a, b, errp)) { | |
2225 | return true; | |
2226 | } | |
2227 | } | |
2228 | } | |
2229 | ||
2230 | return false; | |
2231 | } | |
2232 | ||
c629b6d2 KW |
2233 | static void GRAPH_RDLOCK |
2234 | bdrv_child_perm(BlockDriverState *bs, BlockDriverState *child_bs, | |
2235 | BdrvChild *c, BdrvChildRole role, | |
2236 | BlockReopenQueue *reopen_queue, | |
2237 | uint64_t parent_perm, uint64_t parent_shared, | |
2238 | uint64_t *nperm, uint64_t *nshared) | |
ffd1a5a2 | 2239 | { |
0b3ca76e | 2240 | assert(bs->drv && bs->drv->bdrv_child_perm); |
da359909 | 2241 | GLOBAL_STATE_CODE(); |
e5d8a406 | 2242 | bs->drv->bdrv_child_perm(bs, c, role, reopen_queue, |
0b3ca76e AG |
2243 | parent_perm, parent_shared, |
2244 | nperm, nshared); | |
e0995dc3 | 2245 | /* TODO Take force_share from reopen_queue */ |
ffd1a5a2 FZ |
2246 | if (child_bs && child_bs->force_share) { |
2247 | *nshared = BLK_PERM_ALL; | |
2248 | } | |
2249 | } | |
2250 | ||
bd57f8f7 VSO |
2251 | /* |
2252 | * Adds the whole subtree of @bs (including @bs itself) to the @list (except for | |
2253 | * nodes that are already in the @list, of course) so that final list is | |
2254 | * topologically sorted. Return the result (GSList @list object is updated, so | |
2255 | * don't use old reference after function call). | |
2256 | * | |
2257 | * On function start @list must be already topologically sorted and for any node | |
2258 | * in the @list the whole subtree of the node must be in the @list as well. The | |
2259 | * simplest way to satisfy this criteria: use only result of | |
2260 | * bdrv_topological_dfs() or NULL as @list parameter. | |
2261 | */ | |
3804e3cf KW |
2262 | static GSList * GRAPH_RDLOCK |
2263 | bdrv_topological_dfs(GSList *list, GHashTable *found, BlockDriverState *bs) | |
bd57f8f7 VSO |
2264 | { |
2265 | BdrvChild *child; | |
2266 | g_autoptr(GHashTable) local_found = NULL; | |
2267 | ||
bdb73476 EGE |
2268 | GLOBAL_STATE_CODE(); |
2269 | ||
bd57f8f7 VSO |
2270 | if (!found) { |
2271 | assert(!list); | |
2272 | found = local_found = g_hash_table_new(NULL, NULL); | |
2273 | } | |
2274 | ||
2275 | if (g_hash_table_contains(found, bs)) { | |
2276 | return list; | |
2277 | } | |
2278 | g_hash_table_add(found, bs); | |
2279 | ||
2280 | QLIST_FOREACH(child, &bs->children, next) { | |
2281 | list = bdrv_topological_dfs(list, found, child->bs); | |
2282 | } | |
2283 | ||
2284 | return g_slist_prepend(list, bs); | |
2285 | } | |
2286 | ||
ecb776bd VSO |
2287 | typedef struct BdrvChildSetPermState { |
2288 | BdrvChild *child; | |
2289 | uint64_t old_perm; | |
2290 | uint64_t old_shared_perm; | |
2291 | } BdrvChildSetPermState; | |
b0defa83 VSO |
2292 | |
2293 | static void bdrv_child_set_perm_abort(void *opaque) | |
2294 | { | |
ecb776bd VSO |
2295 | BdrvChildSetPermState *s = opaque; |
2296 | ||
862fded9 EGE |
2297 | GLOBAL_STATE_CODE(); |
2298 | ||
ecb776bd VSO |
2299 | s->child->perm = s->old_perm; |
2300 | s->child->shared_perm = s->old_shared_perm; | |
b0defa83 VSO |
2301 | } |
2302 | ||
2303 | static TransactionActionDrv bdrv_child_set_pem_drv = { | |
2304 | .abort = bdrv_child_set_perm_abort, | |
ecb776bd | 2305 | .clean = g_free, |
b0defa83 VSO |
2306 | }; |
2307 | ||
ecb776bd VSO |
2308 | static void bdrv_child_set_perm(BdrvChild *c, uint64_t perm, |
2309 | uint64_t shared, Transaction *tran) | |
b0defa83 | 2310 | { |
ecb776bd | 2311 | BdrvChildSetPermState *s = g_new(BdrvChildSetPermState, 1); |
862fded9 | 2312 | GLOBAL_STATE_CODE(); |
ecb776bd VSO |
2313 | |
2314 | *s = (BdrvChildSetPermState) { | |
2315 | .child = c, | |
2316 | .old_perm = c->perm, | |
2317 | .old_shared_perm = c->shared_perm, | |
2318 | }; | |
b0defa83 VSO |
2319 | |
2320 | c->perm = perm; | |
2321 | c->shared_perm = shared; | |
2322 | ||
ecb776bd | 2323 | tran_add(tran, &bdrv_child_set_pem_drv, s); |
b0defa83 VSO |
2324 | } |
2325 | ||
bce73bc2 | 2326 | static void GRAPH_RDLOCK bdrv_drv_set_perm_commit(void *opaque) |
2513ef59 VSO |
2327 | { |
2328 | BlockDriverState *bs = opaque; | |
2329 | uint64_t cumulative_perms, cumulative_shared_perms; | |
da359909 | 2330 | GLOBAL_STATE_CODE(); |
2513ef59 VSO |
2331 | |
2332 | if (bs->drv->bdrv_set_perm) { | |
2333 | bdrv_get_cumulative_perm(bs, &cumulative_perms, | |
2334 | &cumulative_shared_perms); | |
2335 | bs->drv->bdrv_set_perm(bs, cumulative_perms, cumulative_shared_perms); | |
2336 | } | |
2337 | } | |
2338 | ||
bce73bc2 | 2339 | static void GRAPH_RDLOCK bdrv_drv_set_perm_abort(void *opaque) |
2513ef59 VSO |
2340 | { |
2341 | BlockDriverState *bs = opaque; | |
da359909 | 2342 | GLOBAL_STATE_CODE(); |
2513ef59 VSO |
2343 | |
2344 | if (bs->drv->bdrv_abort_perm_update) { | |
2345 | bs->drv->bdrv_abort_perm_update(bs); | |
2346 | } | |
2347 | } | |
2348 | ||
2349 | TransactionActionDrv bdrv_drv_set_perm_drv = { | |
2350 | .abort = bdrv_drv_set_perm_abort, | |
2351 | .commit = bdrv_drv_set_perm_commit, | |
2352 | }; | |
2353 | ||
bce73bc2 KW |
2354 | /* |
2355 | * After calling this function, the transaction @tran may only be completed | |
2356 | * while holding a reader lock for the graph. | |
2357 | */ | |
2358 | static int GRAPH_RDLOCK | |
2359 | bdrv_drv_set_perm(BlockDriverState *bs, uint64_t perm, uint64_t shared_perm, | |
2360 | Transaction *tran, Error **errp) | |
2513ef59 | 2361 | { |
da359909 | 2362 | GLOBAL_STATE_CODE(); |
2513ef59 VSO |
2363 | if (!bs->drv) { |
2364 | return 0; | |
2365 | } | |
2366 | ||
2367 | if (bs->drv->bdrv_check_perm) { | |
2368 | int ret = bs->drv->bdrv_check_perm(bs, perm, shared_perm, errp); | |
2369 | if (ret < 0) { | |
2370 | return ret; | |
2371 | } | |
2372 | } | |
2373 | ||
2374 | if (tran) { | |
2375 | tran_add(tran, &bdrv_drv_set_perm_drv, bs); | |
2376 | } | |
2377 | ||
2378 | return 0; | |
2379 | } | |
2380 | ||
0978623e VSO |
2381 | typedef struct BdrvReplaceChildState { |
2382 | BdrvChild *child; | |
2383 | BlockDriverState *old_bs; | |
2384 | } BdrvReplaceChildState; | |
2385 | ||
5661a00d | 2386 | static void GRAPH_WRLOCK bdrv_replace_child_commit(void *opaque) |
0978623e VSO |
2387 | { |
2388 | BdrvReplaceChildState *s = opaque; | |
bdb73476 | 2389 | GLOBAL_STATE_CODE(); |
0978623e | 2390 | |
5661a00d | 2391 | bdrv_schedule_unref(s->old_bs); |
0978623e VSO |
2392 | } |
2393 | ||
5661a00d | 2394 | static void GRAPH_WRLOCK bdrv_replace_child_abort(void *opaque) |
0978623e VSO |
2395 | { |
2396 | BdrvReplaceChildState *s = opaque; | |
2397 | BlockDriverState *new_bs = s->child->bs; | |
2398 | ||
bdb73476 | 2399 | GLOBAL_STATE_CODE(); |
5661a00d | 2400 | assert_bdrv_graph_writable(); |
ad29eb3d | 2401 | |
0f0b1e29 | 2402 | /* old_bs reference is transparently moved from @s to @s->child */ |
23987471 KW |
2403 | if (!s->child->bs) { |
2404 | /* | |
2405 | * The parents were undrained when removing old_bs from the child. New | |
2406 | * requests can't have been made, though, because the child was empty. | |
2407 | * | |
2408 | * TODO Make bdrv_replace_child_noperm() transactionable to avoid | |
2409 | * undraining the parent in the first place. Once this is done, having | |
2410 | * new_bs drained when calling bdrv_replace_child_tran() is not a | |
2411 | * requirement any more. | |
2412 | */ | |
606ed756 | 2413 | bdrv_parent_drained_begin_single(s->child); |
23987471 KW |
2414 | assert(!bdrv_parent_drained_poll_single(s->child)); |
2415 | } | |
2416 | assert(s->child->quiesced_parent); | |
544acc7d | 2417 | bdrv_replace_child_noperm(s->child, s->old_bs); |
ad29eb3d | 2418 | |
0978623e VSO |
2419 | bdrv_unref(new_bs); |
2420 | } | |
2421 | ||
2422 | static TransactionActionDrv bdrv_replace_child_drv = { | |
2423 | .commit = bdrv_replace_child_commit, | |
2424 | .abort = bdrv_replace_child_abort, | |
2425 | .clean = g_free, | |
2426 | }; | |
2427 | ||
2428 | /* | |
4bf021db | 2429 | * bdrv_replace_child_tran |
0978623e VSO |
2430 | * |
2431 | * Note: real unref of old_bs is done only on commit. | |
4bf021db | 2432 | * |
23987471 KW |
2433 | * Both @child->bs and @new_bs (if non-NULL) must be drained. @new_bs must be |
2434 | * kept drained until the transaction is completed. | |
2435 | * | |
5661a00d KW |
2436 | * After calling this function, the transaction @tran may only be completed |
2437 | * while holding a writer lock for the graph. | |
2438 | * | |
4bf021db | 2439 | * The function doesn't update permissions, caller is responsible for this. |
0978623e | 2440 | */ |
2f64e1fc KW |
2441 | static void GRAPH_WRLOCK |
2442 | bdrv_replace_child_tran(BdrvChild *child, BlockDriverState *new_bs, | |
2443 | Transaction *tran) | |
0978623e VSO |
2444 | { |
2445 | BdrvReplaceChildState *s = g_new(BdrvReplaceChildState, 1); | |
23987471 KW |
2446 | |
2447 | assert(child->quiesced_parent); | |
2448 | assert(!new_bs || new_bs->quiesce_counter); | |
2449 | ||
0978623e | 2450 | *s = (BdrvReplaceChildState) { |
0f0b1e29 VSO |
2451 | .child = child, |
2452 | .old_bs = child->bs, | |
0978623e VSO |
2453 | }; |
2454 | tran_add(tran, &bdrv_replace_child_drv, s); | |
2455 | ||
2456 | if (new_bs) { | |
2457 | bdrv_ref(new_bs); | |
2458 | } | |
ad29eb3d | 2459 | |
544acc7d | 2460 | bdrv_replace_child_noperm(child, new_bs); |
0f0b1e29 | 2461 | /* old_bs reference is transparently moved from @child to @s */ |
0978623e VSO |
2462 | } |
2463 | ||
33a610c3 | 2464 | /* |
c20555e1 VSO |
2465 | * Refresh permissions in @bs subtree. The function is intended to be called |
2466 | * after some graph modification that was done without permission update. | |
bce73bc2 KW |
2467 | * |
2468 | * After calling this function, the transaction @tran may only be completed | |
2469 | * while holding a reader lock for the graph. | |
33a610c3 | 2470 | */ |
bce73bc2 KW |
2471 | static int GRAPH_RDLOCK |
2472 | bdrv_node_refresh_perm(BlockDriverState *bs, BlockReopenQueue *q, | |
2473 | Transaction *tran, Error **errp) | |
33a610c3 KW |
2474 | { |
2475 | BlockDriver *drv = bs->drv; | |
2476 | BdrvChild *c; | |
2477 | int ret; | |
c20555e1 | 2478 | uint64_t cumulative_perms, cumulative_shared_perms; |
862fded9 | 2479 | GLOBAL_STATE_CODE(); |
c20555e1 VSO |
2480 | |
2481 | bdrv_get_cumulative_perm(bs, &cumulative_perms, &cumulative_shared_perms); | |
33a610c3 KW |
2482 | |
2483 | /* Write permissions never work with read-only images */ | |
2484 | if ((cumulative_perms & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) && | |
cc022140 | 2485 | !bdrv_is_writable_after_reopen(bs, q)) |
33a610c3 | 2486 | { |
481e0eee HR |
2487 | if (!bdrv_is_writable_after_reopen(bs, NULL)) { |
2488 | error_setg(errp, "Block node is read-only"); | |
2489 | } else { | |
c20555e1 VSO |
2490 | error_setg(errp, "Read-only block node '%s' cannot support " |
2491 | "read-write users", bdrv_get_node_name(bs)); | |
481e0eee HR |
2492 | } |
2493 | ||
33a610c3 KW |
2494 | return -EPERM; |
2495 | } | |
2496 | ||
9c60a5d1 KW |
2497 | /* |
2498 | * Unaligned requests will automatically be aligned to bl.request_alignment | |
2499 | * and without RESIZE we can't extend requests to write to space beyond the | |
2500 | * end of the image, so it's required that the image size is aligned. | |
2501 | */ | |
2502 | if ((cumulative_perms & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) && | |
2503 | !(cumulative_perms & BLK_PERM_RESIZE)) | |
2504 | { | |
2505 | if ((bs->total_sectors * BDRV_SECTOR_SIZE) % bs->bl.request_alignment) { | |
2506 | error_setg(errp, "Cannot get 'write' permission without 'resize': " | |
2507 | "Image size is not a multiple of request " | |
2508 | "alignment"); | |
2509 | return -EPERM; | |
2510 | } | |
2511 | } | |
2512 | ||
33a610c3 KW |
2513 | /* Check this node */ |
2514 | if (!drv) { | |
2515 | return 0; | |
2516 | } | |
2517 | ||
b1d2bbeb | 2518 | ret = bdrv_drv_set_perm(bs, cumulative_perms, cumulative_shared_perms, tran, |
2513ef59 VSO |
2519 | errp); |
2520 | if (ret < 0) { | |
2521 | return ret; | |
33a610c3 KW |
2522 | } |
2523 | ||
78e421c9 | 2524 | /* Drivers that never have children can omit .bdrv_child_perm() */ |
33a610c3 | 2525 | if (!drv->bdrv_child_perm) { |
78e421c9 | 2526 | assert(QLIST_EMPTY(&bs->children)); |
33a610c3 KW |
2527 | return 0; |
2528 | } | |
2529 | ||
2530 | /* Check all children */ | |
2531 | QLIST_FOREACH(c, &bs->children, next) { | |
2532 | uint64_t cur_perm, cur_shared; | |
9eab1544 | 2533 | |
e5d8a406 | 2534 | bdrv_child_perm(bs, c->bs, c, c->role, q, |
ffd1a5a2 FZ |
2535 | cumulative_perms, cumulative_shared_perms, |
2536 | &cur_perm, &cur_shared); | |
ecb776bd | 2537 | bdrv_child_set_perm(c, cur_perm, cur_shared, tran); |
bd57f8f7 VSO |
2538 | } |
2539 | ||
2540 | return 0; | |
2541 | } | |
3ef45e02 | 2542 | |
fb0ff4d1 VSO |
2543 | /* |
2544 | * @list is a product of bdrv_topological_dfs() (may be called several times) - | |
2545 | * a topologically sorted subgraph. | |
bce73bc2 KW |
2546 | * |
2547 | * After calling this function, the transaction @tran may only be completed | |
2548 | * while holding a reader lock for the graph. | |
fb0ff4d1 | 2549 | */ |
3804e3cf KW |
2550 | static int GRAPH_RDLOCK |
2551 | bdrv_do_refresh_perms(GSList *list, BlockReopenQueue *q, Transaction *tran, | |
2552 | Error **errp) | |
bd57f8f7 VSO |
2553 | { |
2554 | int ret; | |
b1d2bbeb | 2555 | BlockDriverState *bs; |
862fded9 | 2556 | GLOBAL_STATE_CODE(); |
bd57f8f7 | 2557 | |
b1d2bbeb VSO |
2558 | for ( ; list; list = list->next) { |
2559 | bs = list->data; | |
2560 | ||
9397c14f | 2561 | if (bdrv_parent_perms_conflict(bs, errp)) { |
b1d2bbeb | 2562 | return -EINVAL; |
bd57f8f7 VSO |
2563 | } |
2564 | ||
c20555e1 | 2565 | ret = bdrv_node_refresh_perm(bs, q, tran, errp); |
33a610c3 KW |
2566 | if (ret < 0) { |
2567 | return ret; | |
2568 | } | |
2569 | } | |
2570 | ||
2571 | return 0; | |
2572 | } | |
2573 | ||
fb0ff4d1 VSO |
2574 | /* |
2575 | * @list is any list of nodes. List is completed by all subtrees and | |
2576 | * topologically sorted. It's not a problem if some node occurs in the @list | |
2577 | * several times. | |
bce73bc2 KW |
2578 | * |
2579 | * After calling this function, the transaction @tran may only be completed | |
2580 | * while holding a reader lock for the graph. | |
fb0ff4d1 | 2581 | */ |
3804e3cf KW |
2582 | static int GRAPH_RDLOCK |
2583 | bdrv_list_refresh_perms(GSList *list, BlockReopenQueue *q, Transaction *tran, | |
2584 | Error **errp) | |
fb0ff4d1 VSO |
2585 | { |
2586 | g_autoptr(GHashTable) found = g_hash_table_new(NULL, NULL); | |
2587 | g_autoptr(GSList) refresh_list = NULL; | |
2588 | ||
2589 | for ( ; list; list = list->next) { | |
2590 | refresh_list = bdrv_topological_dfs(refresh_list, found, list->data); | |
2591 | } | |
2592 | ||
2593 | return bdrv_do_refresh_perms(refresh_list, q, tran, errp); | |
2594 | } | |
2595 | ||
c7a0f2be KW |
2596 | void bdrv_get_cumulative_perm(BlockDriverState *bs, uint64_t *perm, |
2597 | uint64_t *shared_perm) | |
33a610c3 KW |
2598 | { |
2599 | BdrvChild *c; | |
2600 | uint64_t cumulative_perms = 0; | |
2601 | uint64_t cumulative_shared_perms = BLK_PERM_ALL; | |
2602 | ||
b4ad82aa EGE |
2603 | GLOBAL_STATE_CODE(); |
2604 | ||
33a610c3 KW |
2605 | QLIST_FOREACH(c, &bs->parents, next_parent) { |
2606 | cumulative_perms |= c->perm; | |
2607 | cumulative_shared_perms &= c->shared_perm; | |
2608 | } | |
2609 | ||
2610 | *perm = cumulative_perms; | |
2611 | *shared_perm = cumulative_shared_perms; | |
2612 | } | |
2613 | ||
5176196c | 2614 | char *bdrv_perm_names(uint64_t perm) |
d083319f KW |
2615 | { |
2616 | struct perm_name { | |
2617 | uint64_t perm; | |
2618 | const char *name; | |
2619 | } permissions[] = { | |
2620 | { BLK_PERM_CONSISTENT_READ, "consistent read" }, | |
2621 | { BLK_PERM_WRITE, "write" }, | |
2622 | { BLK_PERM_WRITE_UNCHANGED, "write unchanged" }, | |
2623 | { BLK_PERM_RESIZE, "resize" }, | |
d083319f KW |
2624 | { 0, NULL } |
2625 | }; | |
2626 | ||
e2a7423a | 2627 | GString *result = g_string_sized_new(30); |
d083319f KW |
2628 | struct perm_name *p; |
2629 | ||
2630 | for (p = permissions; p->name; p++) { | |
2631 | if (perm & p->perm) { | |
e2a7423a AG |
2632 | if (result->len > 0) { |
2633 | g_string_append(result, ", "); | |
2634 | } | |
2635 | g_string_append(result, p->name); | |
d083319f KW |
2636 | } |
2637 | } | |
2638 | ||
e2a7423a | 2639 | return g_string_free(result, FALSE); |
d083319f KW |
2640 | } |
2641 | ||
33a610c3 | 2642 | |
bce73bc2 KW |
2643 | /* |
2644 | * @tran is allowed to be NULL. In this case no rollback is possible. | |
2645 | * | |
2646 | * After calling this function, the transaction @tran may only be completed | |
2647 | * while holding a reader lock for the graph. | |
2648 | */ | |
3804e3cf KW |
2649 | static int GRAPH_RDLOCK |
2650 | bdrv_refresh_perms(BlockDriverState *bs, Transaction *tran, Error **errp) | |
bb87e4d1 VSO |
2651 | { |
2652 | int ret; | |
f1316edb | 2653 | Transaction *local_tran = NULL; |
b1d2bbeb | 2654 | g_autoptr(GSList) list = bdrv_topological_dfs(NULL, NULL, bs); |
862fded9 | 2655 | GLOBAL_STATE_CODE(); |
bb87e4d1 | 2656 | |
f1316edb VSO |
2657 | if (!tran) { |
2658 | tran = local_tran = tran_new(); | |
2659 | } | |
2660 | ||
fb0ff4d1 | 2661 | ret = bdrv_do_refresh_perms(list, NULL, tran, errp); |
f1316edb VSO |
2662 | |
2663 | if (local_tran) { | |
2664 | tran_finalize(local_tran, ret); | |
2665 | } | |
bb87e4d1 | 2666 | |
b1d2bbeb | 2667 | return ret; |
bb87e4d1 VSO |
2668 | } |
2669 | ||
33a610c3 KW |
2670 | int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, |
2671 | Error **errp) | |
2672 | { | |
1046779e | 2673 | Error *local_err = NULL; |
83928dc4 | 2674 | Transaction *tran = tran_new(); |
33a610c3 KW |
2675 | int ret; |
2676 | ||
b4ad82aa EGE |
2677 | GLOBAL_STATE_CODE(); |
2678 | ||
ecb776bd | 2679 | bdrv_child_set_perm(c, perm, shared, tran); |
83928dc4 | 2680 | |
f1316edb | 2681 | ret = bdrv_refresh_perms(c->bs, tran, &local_err); |
83928dc4 VSO |
2682 | |
2683 | tran_finalize(tran, ret); | |
2684 | ||
33a610c3 | 2685 | if (ret < 0) { |
071b474f VSO |
2686 | if ((perm & ~c->perm) || (c->shared_perm & ~shared)) { |
2687 | /* tighten permissions */ | |
1046779e HR |
2688 | error_propagate(errp, local_err); |
2689 | } else { | |
2690 | /* | |
2691 | * Our caller may intend to only loosen restrictions and | |
2692 | * does not expect this function to fail. Errors are not | |
2693 | * fatal in such a case, so we can just hide them from our | |
2694 | * caller. | |
2695 | */ | |
2696 | error_free(local_err); | |
2697 | ret = 0; | |
2698 | } | |
33a610c3 KW |
2699 | } |
2700 | ||
83928dc4 | 2701 | return ret; |
d5e6f437 KW |
2702 | } |
2703 | ||
c1087f12 HR |
2704 | int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp) |
2705 | { | |
2706 | uint64_t parent_perms, parent_shared; | |
2707 | uint64_t perms, shared; | |
2708 | ||
b4ad82aa EGE |
2709 | GLOBAL_STATE_CODE(); |
2710 | ||
c1087f12 | 2711 | bdrv_get_cumulative_perm(bs, &parent_perms, &parent_shared); |
e5d8a406 | 2712 | bdrv_child_perm(bs, c->bs, c, c->role, NULL, |
bf8e925e | 2713 | parent_perms, parent_shared, &perms, &shared); |
c1087f12 HR |
2714 | |
2715 | return bdrv_child_try_set_perm(c, perms, shared, errp); | |
2716 | } | |
2717 | ||
87278af1 HR |
2718 | /* |
2719 | * Default implementation for .bdrv_child_perm() for block filters: | |
2720 | * Forward CONSISTENT_READ, WRITE, WRITE_UNCHANGED, and RESIZE to the | |
2721 | * filtered child. | |
2722 | */ | |
2723 | static void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, | |
87278af1 HR |
2724 | BdrvChildRole role, |
2725 | BlockReopenQueue *reopen_queue, | |
2726 | uint64_t perm, uint64_t shared, | |
2727 | uint64_t *nperm, uint64_t *nshared) | |
6a1b9ee1 | 2728 | { |
862fded9 | 2729 | GLOBAL_STATE_CODE(); |
e444fa83 KW |
2730 | *nperm = perm & DEFAULT_PERM_PASSTHROUGH; |
2731 | *nshared = (shared & DEFAULT_PERM_PASSTHROUGH) | DEFAULT_PERM_UNCHANGED; | |
6a1b9ee1 KW |
2732 | } |
2733 | ||
70082db4 | 2734 | static void bdrv_default_perms_for_cow(BlockDriverState *bs, BdrvChild *c, |
70082db4 HR |
2735 | BdrvChildRole role, |
2736 | BlockReopenQueue *reopen_queue, | |
2737 | uint64_t perm, uint64_t shared, | |
2738 | uint64_t *nperm, uint64_t *nshared) | |
2739 | { | |
e5d8a406 | 2740 | assert(role & BDRV_CHILD_COW); |
862fded9 | 2741 | GLOBAL_STATE_CODE(); |
70082db4 HR |
2742 | |
2743 | /* | |
2744 | * We want consistent read from backing files if the parent needs it. | |
2745 | * No other operations are performed on backing files. | |
2746 | */ | |
2747 | perm &= BLK_PERM_CONSISTENT_READ; | |
2748 | ||
2749 | /* | |
2750 | * If the parent can deal with changing data, we're okay with a | |
2751 | * writable and resizable backing file. | |
2752 | * TODO Require !(perm & BLK_PERM_CONSISTENT_READ), too? | |
2753 | */ | |
2754 | if (shared & BLK_PERM_WRITE) { | |
2755 | shared = BLK_PERM_WRITE | BLK_PERM_RESIZE; | |
2756 | } else { | |
2757 | shared = 0; | |
2758 | } | |
2759 | ||
64631f36 | 2760 | shared |= BLK_PERM_CONSISTENT_READ | BLK_PERM_WRITE_UNCHANGED; |
70082db4 HR |
2761 | |
2762 | if (bs->open_flags & BDRV_O_INACTIVE) { | |
2763 | shared |= BLK_PERM_WRITE | BLK_PERM_RESIZE; | |
2764 | } | |
2765 | ||
2766 | *nperm = perm; | |
2767 | *nshared = shared; | |
2768 | } | |
2769 | ||
6f838a4b | 2770 | static void bdrv_default_perms_for_storage(BlockDriverState *bs, BdrvChild *c, |
6f838a4b HR |
2771 | BdrvChildRole role, |
2772 | BlockReopenQueue *reopen_queue, | |
2773 | uint64_t perm, uint64_t shared, | |
2774 | uint64_t *nperm, uint64_t *nshared) | |
2775 | { | |
2776 | int flags; | |
2777 | ||
862fded9 | 2778 | GLOBAL_STATE_CODE(); |
e5d8a406 | 2779 | assert(role & (BDRV_CHILD_METADATA | BDRV_CHILD_DATA)); |
6f838a4b HR |
2780 | |
2781 | flags = bdrv_reopen_get_flags(reopen_queue, bs); | |
2782 | ||
2783 | /* | |
2784 | * Apart from the modifications below, the same permissions are | |
2785 | * forwarded and left alone as for filters | |
2786 | */ | |
e5d8a406 | 2787 | bdrv_filter_default_perms(bs, c, role, reopen_queue, |
6f838a4b HR |
2788 | perm, shared, &perm, &shared); |
2789 | ||
f889054f HR |
2790 | if (role & BDRV_CHILD_METADATA) { |
2791 | /* Format drivers may touch metadata even if the guest doesn't write */ | |
2792 | if (bdrv_is_writable_after_reopen(bs, reopen_queue)) { | |
2793 | perm |= BLK_PERM_WRITE | BLK_PERM_RESIZE; | |
2794 | } | |
2795 | ||
2796 | /* | |
2797 | * bs->file always needs to be consistent because of the | |
2798 | * metadata. We can never allow other users to resize or write | |
2799 | * to it. | |
2800 | */ | |
2801 | if (!(flags & BDRV_O_NO_IO)) { | |
2802 | perm |= BLK_PERM_CONSISTENT_READ; | |
2803 | } | |
2804 | shared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); | |
6f838a4b HR |
2805 | } |
2806 | ||
f889054f HR |
2807 | if (role & BDRV_CHILD_DATA) { |
2808 | /* | |
2809 | * Technically, everything in this block is a subset of the | |
2810 | * BDRV_CHILD_METADATA path taken above, and so this could | |
2811 | * be an "else if" branch. However, that is not obvious, and | |
2812 | * this function is not performance critical, therefore we let | |
2813 | * this be an independent "if". | |
2814 | */ | |
2815 | ||
2816 | /* | |
2817 | * We cannot allow other users to resize the file because the | |
2818 | * format driver might have some assumptions about the size | |
2819 | * (e.g. because it is stored in metadata, or because the file | |
2820 | * is split into fixed-size data files). | |
2821 | */ | |
2822 | shared &= ~BLK_PERM_RESIZE; | |
2823 | ||
2824 | /* | |
2825 | * WRITE_UNCHANGED often cannot be performed as such on the | |
2826 | * data file. For example, the qcow2 driver may still need to | |
2827 | * write copied clusters on copy-on-read. | |
2828 | */ | |
2829 | if (perm & BLK_PERM_WRITE_UNCHANGED) { | |
2830 | perm |= BLK_PERM_WRITE; | |
2831 | } | |
2832 | ||
2833 | /* | |
2834 | * If the data file is written to, the format driver may | |
2835 | * expect to be able to resize it by writing beyond the EOF. | |
2836 | */ | |
2837 | if (perm & BLK_PERM_WRITE) { | |
2838 | perm |= BLK_PERM_RESIZE; | |
2839 | } | |
6f838a4b | 2840 | } |
6f838a4b HR |
2841 | |
2842 | if (bs->open_flags & BDRV_O_INACTIVE) { | |
2843 | shared |= BLK_PERM_WRITE | BLK_PERM_RESIZE; | |
2844 | } | |
2845 | ||
2846 | *nperm = perm; | |
2847 | *nshared = shared; | |
2848 | } | |
2849 | ||
2519f549 | 2850 | void bdrv_default_perms(BlockDriverState *bs, BdrvChild *c, |
e5d8a406 | 2851 | BdrvChildRole role, BlockReopenQueue *reopen_queue, |
2519f549 HR |
2852 | uint64_t perm, uint64_t shared, |
2853 | uint64_t *nperm, uint64_t *nshared) | |
2854 | { | |
b4ad82aa | 2855 | GLOBAL_STATE_CODE(); |
2519f549 HR |
2856 | if (role & BDRV_CHILD_FILTERED) { |
2857 | assert(!(role & (BDRV_CHILD_DATA | BDRV_CHILD_METADATA | | |
2858 | BDRV_CHILD_COW))); | |
e5d8a406 | 2859 | bdrv_filter_default_perms(bs, c, role, reopen_queue, |
2519f549 HR |
2860 | perm, shared, nperm, nshared); |
2861 | } else if (role & BDRV_CHILD_COW) { | |
2862 | assert(!(role & (BDRV_CHILD_DATA | BDRV_CHILD_METADATA))); | |
e5d8a406 | 2863 | bdrv_default_perms_for_cow(bs, c, role, reopen_queue, |
2519f549 HR |
2864 | perm, shared, nperm, nshared); |
2865 | } else if (role & (BDRV_CHILD_METADATA | BDRV_CHILD_DATA)) { | |
e5d8a406 | 2866 | bdrv_default_perms_for_storage(bs, c, role, reopen_queue, |
2519f549 HR |
2867 | perm, shared, nperm, nshared); |
2868 | } else { | |
2869 | g_assert_not_reached(); | |
2870 | } | |
2871 | } | |
2872 | ||
7b1d9c4d HR |
2873 | uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm) |
2874 | { | |
2875 | static const uint64_t permissions[] = { | |
2876 | [BLOCK_PERMISSION_CONSISTENT_READ] = BLK_PERM_CONSISTENT_READ, | |
2877 | [BLOCK_PERMISSION_WRITE] = BLK_PERM_WRITE, | |
2878 | [BLOCK_PERMISSION_WRITE_UNCHANGED] = BLK_PERM_WRITE_UNCHANGED, | |
2879 | [BLOCK_PERMISSION_RESIZE] = BLK_PERM_RESIZE, | |
7b1d9c4d HR |
2880 | }; |
2881 | ||
2882 | QEMU_BUILD_BUG_ON(ARRAY_SIZE(permissions) != BLOCK_PERMISSION__MAX); | |
2883 | QEMU_BUILD_BUG_ON(1UL << ARRAY_SIZE(permissions) != BLK_PERM_ALL + 1); | |
2884 | ||
2885 | assert(qapi_perm < BLOCK_PERMISSION__MAX); | |
2886 | ||
2887 | return permissions[qapi_perm]; | |
2888 | } | |
2889 | ||
23987471 KW |
2890 | /* |
2891 | * Replaces the node that a BdrvChild points to without updating permissions. | |
2892 | * | |
2893 | * If @new_bs is non-NULL, the parent of @child must already be drained through | |
31b2ddfe | 2894 | * @child and the caller must hold the AioContext lock for @new_bs. |
23987471 | 2895 | */ |
ad29eb3d KW |
2896 | static void GRAPH_WRLOCK |
2897 | bdrv_replace_child_noperm(BdrvChild *child, BlockDriverState *new_bs) | |
e9740bc6 KW |
2898 | { |
2899 | BlockDriverState *old_bs = child->bs; | |
debc2927 | 2900 | int new_bs_quiesce_counter; |
e9740bc6 | 2901 | |
2cad1ebe | 2902 | assert(!child->frozen); |
23987471 KW |
2903 | |
2904 | /* | |
2905 | * If we want to change the BdrvChild to point to a drained node as its new | |
2906 | * child->bs, we need to make sure that its new parent is drained, too. In | |
2907 | * other words, either child->quiesce_parent must already be true or we must | |
2908 | * be able to set it and keep the parent's quiesce_counter consistent with | |
2909 | * that, but without polling or starting new requests (this function | |
2910 | * guarantees that it doesn't poll, and starting new requests would be | |
2911 | * against the invariants of drain sections). | |
2912 | * | |
2913 | * To keep things simple, we pick the first option (child->quiesce_parent | |
2914 | * must already be true). We also generalise the rule a bit to make it | |
2915 | * easier to verify in callers and more likely to be covered in test cases: | |
2916 | * The parent must be quiesced through this child even if new_bs isn't | |
2917 | * currently drained. | |
2918 | * | |
2919 | * The only exception is for callers that always pass new_bs == NULL. In | |
2920 | * this case, we obviously never need to consider the case of a drained | |
2921 | * new_bs, so we can keep the callers simpler by allowing them not to drain | |
2922 | * the parent. | |
2923 | */ | |
2924 | assert(!new_bs || child->quiesced_parent); | |
bfb8aa6d | 2925 | assert(old_bs != new_bs); |
f0c28327 | 2926 | GLOBAL_STATE_CODE(); |
2cad1ebe | 2927 | |
bb2614e9 FZ |
2928 | if (old_bs && new_bs) { |
2929 | assert(bdrv_get_aio_context(old_bs) == bdrv_get_aio_context(new_bs)); | |
2930 | } | |
debc2927 | 2931 | |
e9740bc6 | 2932 | if (old_bs) { |
bd86fb99 HR |
2933 | if (child->klass->detach) { |
2934 | child->klass->detach(child); | |
d736f119 | 2935 | } |
e9740bc6 KW |
2936 | QLIST_REMOVE(child, next_parent); |
2937 | } | |
36fe1331 KW |
2938 | |
2939 | child->bs = new_bs; | |
2940 | ||
e9740bc6 KW |
2941 | if (new_bs) { |
2942 | QLIST_INSERT_HEAD(&new_bs->parents, child, next_parent); | |
bd86fb99 HR |
2943 | if (child->klass->attach) { |
2944 | child->klass->attach(child); | |
8ee03995 KW |
2945 | } |
2946 | } | |
debc2927 HR |
2947 | |
2948 | /* | |
23987471 KW |
2949 | * If the parent was drained through this BdrvChild previously, but new_bs |
2950 | * is not drained, allow requests to come in only after the new node has | |
2951 | * been attached. | |
debc2927 | 2952 | */ |
57e05be3 KW |
2953 | new_bs_quiesce_counter = (new_bs ? new_bs->quiesce_counter : 0); |
2954 | if (!new_bs_quiesce_counter && child->quiesced_parent) { | |
debc2927 | 2955 | bdrv_parent_drained_end_single(child); |
debc2927 | 2956 | } |
8ee03995 | 2957 | } |
33a610c3 | 2958 | |
04c9c3a5 HR |
2959 | /** |
2960 | * Free the given @child. | |
2961 | * | |
2962 | * The child must be empty (i.e. `child->bs == NULL`) and it must be | |
2963 | * unused (i.e. not in a children list). | |
2964 | */ | |
2965 | static void bdrv_child_free(BdrvChild *child) | |
df581792 | 2966 | { |
548a74c0 | 2967 | assert(!child->bs); |
bdb73476 | 2968 | GLOBAL_STATE_CODE(); |
a225369b | 2969 | assert(!child->next.le_prev); /* not in children list */ |
04c9c3a5 HR |
2970 | |
2971 | g_free(child->name); | |
2972 | g_free(child); | |
548a74c0 | 2973 | } |
d5e6f437 | 2974 | |
548a74c0 | 2975 | typedef struct BdrvAttachChildCommonState { |
5bb04747 | 2976 | BdrvChild *child; |
548a74c0 VSO |
2977 | AioContext *old_parent_ctx; |
2978 | AioContext *old_child_ctx; | |
2979 | } BdrvAttachChildCommonState; | |
2980 | ||
5661a00d | 2981 | static void GRAPH_WRLOCK bdrv_attach_child_common_abort(void *opaque) |
548a74c0 VSO |
2982 | { |
2983 | BdrvAttachChildCommonState *s = opaque; | |
5bb04747 | 2984 | BlockDriverState *bs = s->child->bs; |
548a74c0 | 2985 | |
f0c28327 | 2986 | GLOBAL_STATE_CODE(); |
5661a00d | 2987 | assert_bdrv_graph_writable(); |
ad29eb3d | 2988 | |
5bb04747 | 2989 | bdrv_replace_child_noperm(s->child, NULL); |
548a74c0 VSO |
2990 | |
2991 | if (bdrv_get_aio_context(bs) != s->old_child_ctx) { | |
142e6907 | 2992 | bdrv_try_change_aio_context(bs, s->old_child_ctx, NULL, &error_abort); |
548a74c0 VSO |
2993 | } |
2994 | ||
5bb04747 | 2995 | if (bdrv_child_get_parent_aio_context(s->child) != s->old_parent_ctx) { |
f8be48ad EGE |
2996 | Transaction *tran; |
2997 | GHashTable *visited; | |
2998 | bool ret; | |
548a74c0 | 2999 | |
f8be48ad | 3000 | tran = tran_new(); |
548a74c0 | 3001 | |
f8be48ad EGE |
3002 | /* No need to visit `child`, because it has been detached already */ |
3003 | visited = g_hash_table_new(NULL, NULL); | |
3004 | ret = s->child->klass->change_aio_ctx(s->child, s->old_parent_ctx, | |
3005 | visited, tran, &error_abort); | |
3006 | g_hash_table_destroy(visited); | |
3007 | ||
3008 | /* transaction is supposed to always succeed */ | |
3009 | assert(ret == true); | |
3010 | tran_commit(tran); | |
d5e6f437 KW |
3011 | } |
3012 | ||
5661a00d | 3013 | bdrv_schedule_unref(bs); |
5bb04747 | 3014 | bdrv_child_free(s->child); |
548a74c0 VSO |
3015 | } |
3016 | ||
3017 | static TransactionActionDrv bdrv_attach_child_common_drv = { | |
3018 | .abort = bdrv_attach_child_common_abort, | |
3019 | .clean = g_free, | |
3020 | }; | |
3021 | ||
3022 | /* | |
3023 | * Common part of attaching bdrv child to bs or to blk or to job | |
f8d2ad78 | 3024 | * |
7ec390d5 | 3025 | * Function doesn't update permissions, caller is responsible for this. |
5bb04747 | 3026 | * |
5661a00d KW |
3027 | * After calling this function, the transaction @tran may only be completed |
3028 | * while holding a writer lock for the graph. | |
3029 | * | |
5bb04747 | 3030 | * Returns new created child. |
c066e808 KW |
3031 | * |
3032 | * The caller must hold the AioContext lock for @child_bs. Both @parent_bs and | |
3033 | * @child_bs can move to a different AioContext in this function. Callers must | |
3034 | * make sure that their AioContext locking is still correct after this. | |
548a74c0 | 3035 | */ |
7d4ca9d2 KW |
3036 | static BdrvChild * GRAPH_WRLOCK |
3037 | bdrv_attach_child_common(BlockDriverState *child_bs, | |
3038 | const char *child_name, | |
3039 | const BdrvChildClass *child_class, | |
3040 | BdrvChildRole child_role, | |
3041 | uint64_t perm, uint64_t shared_perm, | |
3042 | void *opaque, | |
3043 | Transaction *tran, Error **errp) | |
548a74c0 VSO |
3044 | { |
3045 | BdrvChild *new_child; | |
c066e808 | 3046 | AioContext *parent_ctx, *new_child_ctx; |
548a74c0 VSO |
3047 | AioContext *child_ctx = bdrv_get_aio_context(child_bs); |
3048 | ||
da261b69 | 3049 | assert(child_class->get_parent_desc); |
bdb73476 | 3050 | GLOBAL_STATE_CODE(); |
548a74c0 VSO |
3051 | |
3052 | new_child = g_new(BdrvChild, 1); | |
3053 | *new_child = (BdrvChild) { | |
d5e6f437 KW |
3054 | .bs = NULL, |
3055 | .name = g_strdup(child_name), | |
bd86fb99 | 3056 | .klass = child_class, |
258b7765 | 3057 | .role = child_role, |
d5e6f437 KW |
3058 | .perm = perm, |
3059 | .shared_perm = shared_perm, | |
3060 | .opaque = opaque, | |
df581792 KW |
3061 | }; |
3062 | ||
548a74c0 VSO |
3063 | /* |
3064 | * If the AioContexts don't match, first try to move the subtree of | |
132ada80 | 3065 | * child_bs into the AioContext of the new parent. If this doesn't work, |
548a74c0 VSO |
3066 | * try moving the parent into the AioContext of child_bs instead. |
3067 | */ | |
3068 | parent_ctx = bdrv_child_get_parent_aio_context(new_child); | |
3069 | if (child_ctx != parent_ctx) { | |
3070 | Error *local_err = NULL; | |
142e6907 EGE |
3071 | int ret = bdrv_try_change_aio_context(child_bs, parent_ctx, NULL, |
3072 | &local_err); | |
548a74c0 | 3073 | |
f8be48ad EGE |
3074 | if (ret < 0 && child_class->change_aio_ctx) { |
3075 | Transaction *tran = tran_new(); | |
3076 | GHashTable *visited = g_hash_table_new(NULL, NULL); | |
3077 | bool ret_child; | |
3078 | ||
3079 | g_hash_table_add(visited, new_child); | |
3080 | ret_child = child_class->change_aio_ctx(new_child, child_ctx, | |
3081 | visited, tran, NULL); | |
3082 | if (ret_child == true) { | |
132ada80 KW |
3083 | error_free(local_err); |
3084 | ret = 0; | |
132ada80 | 3085 | } |
f8be48ad EGE |
3086 | tran_finalize(tran, ret_child == true ? 0 : -1); |
3087 | g_hash_table_destroy(visited); | |
132ada80 | 3088 | } |
548a74c0 | 3089 | |
132ada80 KW |
3090 | if (ret < 0) { |
3091 | error_propagate(errp, local_err); | |
04c9c3a5 | 3092 | bdrv_child_free(new_child); |
5bb04747 | 3093 | return NULL; |
132ada80 KW |
3094 | } |
3095 | } | |
3096 | ||
c066e808 KW |
3097 | new_child_ctx = bdrv_get_aio_context(child_bs); |
3098 | if (new_child_ctx != child_ctx) { | |
3099 | aio_context_release(child_ctx); | |
3100 | aio_context_acquire(new_child_ctx); | |
3101 | } | |
3102 | ||
548a74c0 | 3103 | bdrv_ref(child_bs); |
23987471 KW |
3104 | /* |
3105 | * Let every new BdrvChild start with a drained parent. Inserting the child | |
3106 | * in the graph with bdrv_replace_child_noperm() will undrain it if | |
3107 | * @child_bs is not drained. | |
3108 | * | |
3109 | * The child was only just created and is not yet visible in global state | |
3110 | * until bdrv_replace_child_noperm() inserts it into the graph, so nobody | |
3111 | * could have sent requests and polling is not necessary. | |
3112 | * | |
3113 | * Note that this means that the parent isn't fully drained yet, we only | |
3114 | * stop new requests from coming in. This is fine, we don't care about the | |
3115 | * old requests here, they are not for this child. If another place enters a | |
3116 | * drain section for the same parent, but wants it to be fully quiesced, it | |
3117 | * will not run most of the the code in .drained_begin() again (which is not | |
3118 | * a problem, we already did this), but it will still poll until the parent | |
3119 | * is fully quiesced, so it will not be negatively affected either. | |
3120 | */ | |
606ed756 | 3121 | bdrv_parent_drained_begin_single(new_child); |
544acc7d | 3122 | bdrv_replace_child_noperm(new_child, child_bs); |
b4b059f6 | 3123 | |
548a74c0 VSO |
3124 | BdrvAttachChildCommonState *s = g_new(BdrvAttachChildCommonState, 1); |
3125 | *s = (BdrvAttachChildCommonState) { | |
5bb04747 | 3126 | .child = new_child, |
548a74c0 VSO |
3127 | .old_parent_ctx = parent_ctx, |
3128 | .old_child_ctx = child_ctx, | |
3129 | }; | |
3130 | tran_add(tran, &bdrv_attach_child_common_drv, s); | |
3131 | ||
c066e808 KW |
3132 | if (new_child_ctx != child_ctx) { |
3133 | aio_context_release(new_child_ctx); | |
3134 | aio_context_acquire(child_ctx); | |
3135 | } | |
3136 | ||
5bb04747 | 3137 | return new_child; |
548a74c0 VSO |
3138 | } |
3139 | ||
f8d2ad78 | 3140 | /* |
7ec390d5 | 3141 | * Function doesn't update permissions, caller is responsible for this. |
c066e808 KW |
3142 | * |
3143 | * The caller must hold the AioContext lock for @child_bs. Both @parent_bs and | |
3144 | * @child_bs can move to a different AioContext in this function. Callers must | |
3145 | * make sure that their AioContext locking is still correct after this. | |
5661a00d KW |
3146 | * |
3147 | * After calling this function, the transaction @tran may only be completed | |
3148 | * while holding a writer lock for the graph. | |
f8d2ad78 | 3149 | */ |
7d4ca9d2 KW |
3150 | static BdrvChild * GRAPH_WRLOCK |
3151 | bdrv_attach_child_noperm(BlockDriverState *parent_bs, | |
3152 | BlockDriverState *child_bs, | |
3153 | const char *child_name, | |
3154 | const BdrvChildClass *child_class, | |
3155 | BdrvChildRole child_role, | |
3156 | Transaction *tran, | |
3157 | Error **errp) | |
aa5a04c7 | 3158 | { |
aa5a04c7 VSO |
3159 | uint64_t perm, shared_perm; |
3160 | ||
3161 | assert(parent_bs->drv); | |
bdb73476 | 3162 | GLOBAL_STATE_CODE(); |
aa5a04c7 | 3163 | |
bfb8aa6d KW |
3164 | if (bdrv_recurse_has_child(child_bs, parent_bs)) { |
3165 | error_setg(errp, "Making '%s' a %s child of '%s' would create a cycle", | |
3166 | child_bs->node_name, child_name, parent_bs->node_name); | |
5bb04747 | 3167 | return NULL; |
bfb8aa6d KW |
3168 | } |
3169 | ||
aa5a04c7 VSO |
3170 | bdrv_get_cumulative_perm(parent_bs, &perm, &shared_perm); |
3171 | bdrv_child_perm(parent_bs, child_bs, NULL, child_role, NULL, | |
3172 | perm, shared_perm, &perm, &shared_perm); | |
3173 | ||
5bb04747 VSO |
3174 | return bdrv_attach_child_common(child_bs, child_name, child_class, |
3175 | child_role, perm, shared_perm, parent_bs, | |
3176 | tran, errp); | |
aa5a04c7 VSO |
3177 | } |
3178 | ||
548a74c0 VSO |
3179 | /* |
3180 | * This function steals the reference to child_bs from the caller. | |
3181 | * That reference is later dropped by bdrv_root_unref_child(). | |
3182 | * | |
3183 | * On failure NULL is returned, errp is set and the reference to | |
3184 | * child_bs is also dropped. | |
3185 | * | |
3186 | * The caller must hold the AioContext lock @child_bs, but not that of @ctx | |
3187 | * (unless @child_bs is already in @ctx). | |
3188 | */ | |
3189 | BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, | |
3190 | const char *child_name, | |
3191 | const BdrvChildClass *child_class, | |
3192 | BdrvChildRole child_role, | |
3193 | uint64_t perm, uint64_t shared_perm, | |
3194 | void *opaque, Error **errp) | |
3195 | { | |
3196 | int ret; | |
5bb04747 | 3197 | BdrvChild *child; |
548a74c0 VSO |
3198 | Transaction *tran = tran_new(); |
3199 | ||
b4ad82aa EGE |
3200 | GLOBAL_STATE_CODE(); |
3201 | ||
7d4ca9d2 KW |
3202 | bdrv_graph_wrlock(child_bs); |
3203 | ||
5bb04747 | 3204 | child = bdrv_attach_child_common(child_bs, child_name, child_class, |
548a74c0 | 3205 | child_role, perm, shared_perm, opaque, |
5bb04747 VSO |
3206 | tran, errp); |
3207 | if (!child) { | |
3208 | ret = -EINVAL; | |
e878bb12 | 3209 | goto out; |
548a74c0 VSO |
3210 | } |
3211 | ||
f1316edb | 3212 | ret = bdrv_refresh_perms(child_bs, tran, errp); |
548a74c0 | 3213 | |
e878bb12 KW |
3214 | out: |
3215 | tran_finalize(tran, ret); | |
5661a00d | 3216 | bdrv_graph_wrunlock(); |
f8d2ad78 | 3217 | |
548a74c0 | 3218 | bdrv_unref(child_bs); |
5bb04747 VSO |
3219 | |
3220 | return ret < 0 ? NULL : child; | |
df581792 KW |
3221 | } |
3222 | ||
b441dc71 AG |
3223 | /* |
3224 | * This function transfers the reference to child_bs from the caller | |
3225 | * to parent_bs. That reference is later dropped by parent_bs on | |
3226 | * bdrv_close() or if someone calls bdrv_unref_child(). | |
3227 | * | |
3228 | * On failure NULL is returned, errp is set and the reference to | |
3229 | * child_bs is also dropped. | |
132ada80 KW |
3230 | * |
3231 | * If @parent_bs and @child_bs are in different AioContexts, the caller must | |
3232 | * hold the AioContext lock for @child_bs, but not for @parent_bs. | |
b441dc71 | 3233 | */ |
98292c61 WC |
3234 | BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, |
3235 | BlockDriverState *child_bs, | |
3236 | const char *child_name, | |
bd86fb99 | 3237 | const BdrvChildClass *child_class, |
258b7765 | 3238 | BdrvChildRole child_role, |
8b2ff529 | 3239 | Error **errp) |
f21d96d0 | 3240 | { |
aa5a04c7 | 3241 | int ret; |
5bb04747 | 3242 | BdrvChild *child; |
aa5a04c7 | 3243 | Transaction *tran = tran_new(); |
f68c598b | 3244 | |
f791bf7f EGE |
3245 | GLOBAL_STATE_CODE(); |
3246 | ||
5bb04747 VSO |
3247 | child = bdrv_attach_child_noperm(parent_bs, child_bs, child_name, |
3248 | child_class, child_role, tran, errp); | |
3249 | if (!child) { | |
3250 | ret = -EINVAL; | |
aa5a04c7 VSO |
3251 | goto out; |
3252 | } | |
d5e6f437 | 3253 | |
f1316edb | 3254 | ret = bdrv_refresh_perms(parent_bs, tran, errp); |
aa5a04c7 VSO |
3255 | if (ret < 0) { |
3256 | goto out; | |
d5e6f437 KW |
3257 | } |
3258 | ||
aa5a04c7 VSO |
3259 | out: |
3260 | tran_finalize(tran, ret); | |
3261 | ||
afdaeb9e | 3262 | bdrv_schedule_unref(child_bs); |
aa5a04c7 | 3263 | |
5bb04747 | 3264 | return ret < 0 ? NULL : child; |
f21d96d0 KW |
3265 | } |
3266 | ||
7b99a266 | 3267 | /* Callers must ensure that child->frozen is false. */ |
f21d96d0 | 3268 | void bdrv_root_unref_child(BdrvChild *child) |
33a60407 | 3269 | { |
00eb93b5 | 3270 | BlockDriverState *child_bs = child->bs; |
779020cb | 3271 | |
f791bf7f | 3272 | GLOBAL_STATE_CODE(); |
00eb93b5 VSO |
3273 | bdrv_replace_child_noperm(child, NULL); |
3274 | bdrv_child_free(child); | |
3275 | ||
3276 | if (child_bs) { | |
3277 | /* | |
3278 | * Update permissions for old node. We're just taking a parent away, so | |
3279 | * we're loosening restrictions. Errors of permission update are not | |
3280 | * fatal in this case, ignore them. | |
3281 | */ | |
f1316edb | 3282 | bdrv_refresh_perms(child_bs, NULL, NULL); |
00eb93b5 VSO |
3283 | |
3284 | /* | |
3285 | * When the parent requiring a non-default AioContext is removed, the | |
3286 | * node moves back to the main AioContext | |
3287 | */ | |
3288 | bdrv_try_change_aio_context(child_bs, qemu_get_aio_context(), NULL, | |
3289 | NULL); | |
3290 | } | |
f791bf7f | 3291 | |
ede01e46 | 3292 | bdrv_schedule_unref(child_bs); |
f21d96d0 KW |
3293 | } |
3294 | ||
332b3a17 VSO |
3295 | typedef struct BdrvSetInheritsFrom { |
3296 | BlockDriverState *bs; | |
3297 | BlockDriverState *old_inherits_from; | |
3298 | } BdrvSetInheritsFrom; | |
3299 | ||
3300 | static void bdrv_set_inherits_from_abort(void *opaque) | |
3301 | { | |
3302 | BdrvSetInheritsFrom *s = opaque; | |
3303 | ||
3304 | s->bs->inherits_from = s->old_inherits_from; | |
3305 | } | |
3306 | ||
3307 | static TransactionActionDrv bdrv_set_inherits_from_drv = { | |
3308 | .abort = bdrv_set_inherits_from_abort, | |
3309 | .clean = g_free, | |
3310 | }; | |
3311 | ||
3312 | /* @tran is allowed to be NULL. In this case no rollback is possible */ | |
3313 | static void bdrv_set_inherits_from(BlockDriverState *bs, | |
3314 | BlockDriverState *new_inherits_from, | |
3315 | Transaction *tran) | |
3316 | { | |
3317 | if (tran) { | |
3318 | BdrvSetInheritsFrom *s = g_new(BdrvSetInheritsFrom, 1); | |
3319 | ||
3320 | *s = (BdrvSetInheritsFrom) { | |
3321 | .bs = bs, | |
3322 | .old_inherits_from = bs->inherits_from, | |
3323 | }; | |
3324 | ||
3325 | tran_add(tran, &bdrv_set_inherits_from_drv, s); | |
3326 | } | |
3327 | ||
3328 | bs->inherits_from = new_inherits_from; | |
3329 | } | |
3330 | ||
3cf746b3 HR |
3331 | /** |
3332 | * Clear all inherits_from pointers from children and grandchildren of | |
3333 | * @root that point to @root, where necessary. | |
332b3a17 | 3334 | * @tran is allowed to be NULL. In this case no rollback is possible |
3cf746b3 | 3335 | */ |
32a8aba3 KW |
3336 | static void GRAPH_WRLOCK |
3337 | bdrv_unset_inherits_from(BlockDriverState *root, BdrvChild *child, | |
3338 | Transaction *tran) | |
f21d96d0 | 3339 | { |
3cf746b3 | 3340 | BdrvChild *c; |
4e4bf5c4 | 3341 | |
3cf746b3 HR |
3342 | if (child->bs->inherits_from == root) { |
3343 | /* | |
3344 | * Remove inherits_from only when the last reference between root and | |
3345 | * child->bs goes away. | |
3346 | */ | |
3347 | QLIST_FOREACH(c, &root->children, next) { | |
4e4bf5c4 KW |
3348 | if (c != child && c->bs == child->bs) { |
3349 | break; | |
3350 | } | |
3351 | } | |
3352 | if (c == NULL) { | |
332b3a17 | 3353 | bdrv_set_inherits_from(child->bs, NULL, tran); |
4e4bf5c4 | 3354 | } |
33a60407 KW |
3355 | } |
3356 | ||
3cf746b3 | 3357 | QLIST_FOREACH(c, &child->bs->children, next) { |
332b3a17 | 3358 | bdrv_unset_inherits_from(root, c, tran); |
3cf746b3 HR |
3359 | } |
3360 | } | |
3361 | ||
7b99a266 | 3362 | /* Callers must ensure that child->frozen is false. */ |
3cf746b3 HR |
3363 | void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child) |
3364 | { | |
f791bf7f | 3365 | GLOBAL_STATE_CODE(); |
3cf746b3 HR |
3366 | if (child == NULL) { |
3367 | return; | |
3368 | } | |
3369 | ||
332b3a17 | 3370 | bdrv_unset_inherits_from(parent, child, NULL); |
f21d96d0 | 3371 | bdrv_root_unref_child(child); |
33a60407 KW |
3372 | } |
3373 | ||
5c8cab48 | 3374 | |
356f4ef6 KW |
3375 | static void GRAPH_RDLOCK |
3376 | bdrv_parent_cb_change_media(BlockDriverState *bs, bool load) | |
5c8cab48 KW |
3377 | { |
3378 | BdrvChild *c; | |
f0c28327 | 3379 | GLOBAL_STATE_CODE(); |
5c8cab48 | 3380 | QLIST_FOREACH(c, &bs->parents, next_parent) { |
bd86fb99 HR |
3381 | if (c->klass->change_media) { |
3382 | c->klass->change_media(c, load); | |
5c8cab48 KW |
3383 | } |
3384 | } | |
3385 | } | |
3386 | ||
0065c455 AG |
3387 | /* Return true if you can reach parent going through child->inherits_from |
3388 | * recursively. If parent or child are NULL, return false */ | |
3389 | static bool bdrv_inherits_from_recursive(BlockDriverState *child, | |
3390 | BlockDriverState *parent) | |
3391 | { | |
3392 | while (child && child != parent) { | |
3393 | child = child->inherits_from; | |
3394 | } | |
3395 | ||
3396 | return child != NULL; | |
3397 | } | |
3398 | ||
25191e5f HR |
3399 | /* |
3400 | * Return the BdrvChildRole for @bs's backing child. bs->backing is | |
3401 | * mostly used for COW backing children (role = COW), but also for | |
3402 | * filtered children (role = FILTERED | PRIMARY). | |
3403 | */ | |
3404 | static BdrvChildRole bdrv_backing_role(BlockDriverState *bs) | |
3405 | { | |
3406 | if (bs->drv && bs->drv->is_filter) { | |
3407 | return BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY; | |
3408 | } else { | |
3409 | return BDRV_CHILD_COW; | |
3410 | } | |
3411 | } | |
3412 | ||
5db15a57 | 3413 | /* |
e9238278 VSO |
3414 | * Sets the bs->backing or bs->file link of a BDS. A new reference is created; |
3415 | * callers which don't need their own reference any more must call bdrv_unref(). | |
7ec390d5 | 3416 | * |
7d4ca9d2 KW |
3417 | * If the respective child is already present (i.e. we're detaching a node), |
3418 | * that child node must be drained. | |
3419 | * | |
7ec390d5 | 3420 | * Function doesn't update permissions, caller is responsible for this. |
4b408668 KW |
3421 | * |
3422 | * The caller must hold the AioContext lock for @child_bs. Both @parent_bs and | |
3423 | * @child_bs can move to a different AioContext in this function. Callers must | |
3424 | * make sure that their AioContext locking is still correct after this. | |
5661a00d KW |
3425 | * |
3426 | * After calling this function, the transaction @tran may only be completed | |
3427 | * while holding a writer lock for the graph. | |
5db15a57 | 3428 | */ |
7d4ca9d2 KW |
3429 | static int GRAPH_WRLOCK |
3430 | bdrv_set_file_or_backing_noperm(BlockDriverState *parent_bs, | |
3431 | BlockDriverState *child_bs, | |
3432 | bool is_backing, | |
3433 | Transaction *tran, Error **errp) | |
8d24cce1 | 3434 | { |
e9238278 VSO |
3435 | bool update_inherits_from = |
3436 | bdrv_inherits_from_recursive(child_bs, parent_bs); | |
3437 | BdrvChild *child = is_backing ? parent_bs->backing : parent_bs->file; | |
3438 | BdrvChildRole role; | |
0065c455 | 3439 | |
bdb73476 EGE |
3440 | GLOBAL_STATE_CODE(); |
3441 | ||
e9238278 VSO |
3442 | if (!parent_bs->drv) { |
3443 | /* | |
3444 | * Node without drv is an object without a class :/. TODO: finally fix | |
3445 | * qcow2 driver to never clear bs->drv and implement format corruption | |
3446 | * handling in other way. | |
3447 | */ | |
3448 | error_setg(errp, "Node corrupted"); | |
3449 | return -EINVAL; | |
3450 | } | |
3451 | ||
3452 | if (child && child->frozen) { | |
3453 | error_setg(errp, "Cannot change frozen '%s' link from '%s' to '%s'", | |
3454 | child->name, parent_bs->node_name, child->bs->node_name); | |
a1e708fc | 3455 | return -EPERM; |
2cad1ebe AG |
3456 | } |
3457 | ||
25f78d9e VSO |
3458 | if (is_backing && !parent_bs->drv->is_filter && |
3459 | !parent_bs->drv->supports_backing) | |
3460 | { | |
3461 | error_setg(errp, "Driver '%s' of node '%s' does not support backing " | |
3462 | "files", parent_bs->drv->format_name, parent_bs->node_name); | |
3463 | return -EINVAL; | |
3464 | } | |
3465 | ||
e9238278 VSO |
3466 | if (parent_bs->drv->is_filter) { |
3467 | role = BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY; | |
3468 | } else if (is_backing) { | |
3469 | role = BDRV_CHILD_COW; | |
3470 | } else { | |
3471 | /* | |
3472 | * We only can use same role as it is in existing child. We don't have | |
3473 | * infrastructure to determine role of file child in generic way | |
3474 | */ | |
3475 | if (!child) { | |
3476 | error_setg(errp, "Cannot set file child to format node without " | |
3477 | "file child"); | |
3478 | return -EINVAL; | |
3479 | } | |
3480 | role = child->role; | |
826b6ca0 FZ |
3481 | } |
3482 | ||
e9238278 | 3483 | if (child) { |
7d4ca9d2 | 3484 | assert(child->bs->quiesce_counter); |
e9238278 | 3485 | bdrv_unset_inherits_from(parent_bs, child, tran); |
57f08941 | 3486 | bdrv_remove_child(child, tran); |
e9238278 VSO |
3487 | } |
3488 | ||
3489 | if (!child_bs) { | |
8d24cce1 FZ |
3490 | goto out; |
3491 | } | |
12fa4af6 | 3492 | |
5bb04747 VSO |
3493 | child = bdrv_attach_child_noperm(parent_bs, child_bs, |
3494 | is_backing ? "backing" : "file", | |
3495 | &child_of_bds, role, | |
3496 | tran, errp); | |
3497 | if (!child) { | |
3498 | return -EINVAL; | |
a1e708fc VSO |
3499 | } |
3500 | ||
160333e1 VSO |
3501 | |
3502 | /* | |
e9238278 | 3503 | * If inherits_from pointed recursively to bs then let's update it to |
160333e1 VSO |
3504 | * point directly to bs (else it will become NULL). |
3505 | */ | |
a1e708fc | 3506 | if (update_inherits_from) { |
e9238278 | 3507 | bdrv_set_inherits_from(child_bs, parent_bs, tran); |
0065c455 | 3508 | } |
826b6ca0 | 3509 | |
8d24cce1 | 3510 | out: |
e9238278 | 3511 | bdrv_refresh_limits(parent_bs, tran, NULL); |
160333e1 VSO |
3512 | |
3513 | return 0; | |
3514 | } | |
3515 | ||
4b408668 KW |
3516 | /* |
3517 | * The caller must hold the AioContext lock for @backing_hd. Both @bs and | |
3518 | * @backing_hd can move to a different AioContext in this function. Callers must | |
3519 | * make sure that their AioContext locking is still correct after this. | |
7d4ca9d2 KW |
3520 | * |
3521 | * If a backing child is already present (i.e. we're detaching a node), that | |
3522 | * child node must be drained. | |
5661a00d KW |
3523 | * |
3524 | * After calling this function, the transaction @tran may only be completed | |
3525 | * while holding a writer lock for the graph. | |
4b408668 | 3526 | */ |
7d4ca9d2 KW |
3527 | static int GRAPH_WRLOCK |
3528 | bdrv_set_backing_noperm(BlockDriverState *bs, | |
3529 | BlockDriverState *backing_hd, | |
3530 | Transaction *tran, Error **errp) | |
e9238278 | 3531 | { |
bdb73476 | 3532 | GLOBAL_STATE_CODE(); |
e9238278 VSO |
3533 | return bdrv_set_file_or_backing_noperm(bs, backing_hd, true, tran, errp); |
3534 | } | |
3535 | ||
92140b9f KW |
3536 | int bdrv_set_backing_hd_drained(BlockDriverState *bs, |
3537 | BlockDriverState *backing_hd, | |
3538 | Error **errp) | |
160333e1 VSO |
3539 | { |
3540 | int ret; | |
3541 | Transaction *tran = tran_new(); | |
3542 | ||
f791bf7f | 3543 | GLOBAL_STATE_CODE(); |
92140b9f | 3544 | assert(bs->quiesce_counter > 0); |
7d4ca9d2 KW |
3545 | if (bs->backing) { |
3546 | assert(bs->backing->bs->quiesce_counter > 0); | |
3547 | } | |
3548 | bdrv_graph_wrlock(backing_hd); | |
c0829cb1 | 3549 | |
160333e1 VSO |
3550 | ret = bdrv_set_backing_noperm(bs, backing_hd, tran, errp); |
3551 | if (ret < 0) { | |
3552 | goto out; | |
3553 | } | |
3554 | ||
f1316edb | 3555 | ret = bdrv_refresh_perms(bs, tran, errp); |
160333e1 VSO |
3556 | out: |
3557 | tran_finalize(tran, ret); | |
5661a00d | 3558 | bdrv_graph_wrunlock(); |
92140b9f KW |
3559 | return ret; |
3560 | } | |
a1e708fc | 3561 | |
92140b9f KW |
3562 | int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, |
3563 | Error **errp) | |
3564 | { | |
7d4ca9d2 | 3565 | BlockDriverState *drain_bs = bs->backing ? bs->backing->bs : bs; |
92140b9f KW |
3566 | int ret; |
3567 | GLOBAL_STATE_CODE(); | |
3568 | ||
7d4ca9d2 KW |
3569 | bdrv_ref(drain_bs); |
3570 | bdrv_drained_begin(drain_bs); | |
92140b9f | 3571 | ret = bdrv_set_backing_hd_drained(bs, backing_hd, errp); |
7d4ca9d2 KW |
3572 | bdrv_drained_end(drain_bs); |
3573 | bdrv_unref(drain_bs); | |
c0829cb1 | 3574 | |
a1e708fc | 3575 | return ret; |
8d24cce1 FZ |
3576 | } |
3577 | ||
31ca6d07 KW |
3578 | /* |
3579 | * Opens the backing file for a BlockDriverState if not yet open | |
3580 | * | |
d9b7b057 KW |
3581 | * bdref_key specifies the key for the image's BlockdevRef in the options QDict. |
3582 | * That QDict has to be flattened; therefore, if the BlockdevRef is a QDict | |
3583 | * itself, all options starting with "${bdref_key}." are considered part of the | |
3584 | * BlockdevRef. | |
3585 | * | |
2626d27f KW |
3586 | * The caller must hold the main AioContext lock. |
3587 | * | |
d9b7b057 | 3588 | * TODO Can this be unified with bdrv_open_image()? |
31ca6d07 | 3589 | */ |
d9b7b057 KW |
3590 | int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, |
3591 | const char *bdref_key, Error **errp) | |
9156df12 | 3592 | { |
6b6833c1 | 3593 | char *backing_filename = NULL; |
d9b7b057 KW |
3594 | char *bdref_key_dot; |
3595 | const char *reference = NULL; | |
317fc44e | 3596 | int ret = 0; |
998c2019 | 3597 | bool implicit_backing = false; |
8d24cce1 | 3598 | BlockDriverState *backing_hd; |
8aa04542 | 3599 | AioContext *backing_hd_ctx; |
d9b7b057 KW |
3600 | QDict *options; |
3601 | QDict *tmp_parent_options = NULL; | |
34b5d2c6 | 3602 | Error *local_err = NULL; |
9156df12 | 3603 | |
f791bf7f EGE |
3604 | GLOBAL_STATE_CODE(); |
3605 | ||
760e0063 | 3606 | if (bs->backing != NULL) { |
1ba4b6a5 | 3607 | goto free_exit; |
9156df12 PB |
3608 | } |
3609 | ||
31ca6d07 | 3610 | /* NULL means an empty set of options */ |
d9b7b057 KW |
3611 | if (parent_options == NULL) { |
3612 | tmp_parent_options = qdict_new(); | |
3613 | parent_options = tmp_parent_options; | |
31ca6d07 KW |
3614 | } |
3615 | ||
9156df12 | 3616 | bs->open_flags &= ~BDRV_O_NO_BACKING; |
d9b7b057 KW |
3617 | |
3618 | bdref_key_dot = g_strdup_printf("%s.", bdref_key); | |
3619 | qdict_extract_subqdict(parent_options, &options, bdref_key_dot); | |
3620 | g_free(bdref_key_dot); | |
3621 | ||
129c7d1c MA |
3622 | /* |
3623 | * Caution: while qdict_get_try_str() is fine, getting non-string | |
3624 | * types would require more care. When @parent_options come from | |
3625 | * -blockdev or blockdev_add, its members are typed according to | |
3626 | * the QAPI schema, but when they come from -drive, they're all | |
3627 | * QString. | |
3628 | */ | |
d9b7b057 KW |
3629 | reference = qdict_get_try_str(parent_options, bdref_key); |
3630 | if (reference || qdict_haskey(options, "file.filename")) { | |
6b6833c1 | 3631 | /* keep backing_filename NULL */ |
1cb6f506 | 3632 | } else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) { |
cb3e7f08 | 3633 | qobject_unref(options); |
1ba4b6a5 | 3634 | goto free_exit; |
dbecebdd | 3635 | } else { |
998c2019 HR |
3636 | if (qdict_size(options) == 0) { |
3637 | /* If the user specifies options that do not modify the | |
3638 | * backing file's behavior, we might still consider it the | |
3639 | * implicit backing file. But it's easier this way, and | |
3640 | * just specifying some of the backing BDS's options is | |
3641 | * only possible with -drive anyway (otherwise the QAPI | |
3642 | * schema forces the user to specify everything). */ | |
3643 | implicit_backing = !strcmp(bs->auto_backing_file, bs->backing_file); | |
3644 | } | |
3645 | ||
6b6833c1 | 3646 | backing_filename = bdrv_get_full_backing_filename(bs, &local_err); |
9f07429e HR |
3647 | if (local_err) { |
3648 | ret = -EINVAL; | |
3649 | error_propagate(errp, local_err); | |
cb3e7f08 | 3650 | qobject_unref(options); |
9f07429e HR |
3651 | goto free_exit; |
3652 | } | |
9156df12 PB |
3653 | } |
3654 | ||
8ee79e70 KW |
3655 | if (!bs->drv || !bs->drv->supports_backing) { |
3656 | ret = -EINVAL; | |
3657 | error_setg(errp, "Driver doesn't support backing files"); | |
cb3e7f08 | 3658 | qobject_unref(options); |
8ee79e70 KW |
3659 | goto free_exit; |
3660 | } | |
3661 | ||
6bff597b PK |
3662 | if (!reference && |
3663 | bs->backing_format[0] != '\0' && !qdict_haskey(options, "driver")) { | |
46f5ac20 | 3664 | qdict_put_str(options, "driver", bs->backing_format); |
9156df12 PB |
3665 | } |
3666 | ||
6b6833c1 | 3667 | backing_hd = bdrv_open_inherit(backing_filename, reference, options, 0, bs, |
25191e5f | 3668 | &child_of_bds, bdrv_backing_role(bs), errp); |
5b363937 | 3669 | if (!backing_hd) { |
9156df12 | 3670 | bs->open_flags |= BDRV_O_NO_BACKING; |
e43bfd9c | 3671 | error_prepend(errp, "Could not open backing file: "); |
5b363937 | 3672 | ret = -EINVAL; |
1ba4b6a5 | 3673 | goto free_exit; |
9156df12 | 3674 | } |
df581792 | 3675 | |
998c2019 HR |
3676 | if (implicit_backing) { |
3677 | bdrv_refresh_filename(backing_hd); | |
3678 | pstrcpy(bs->auto_backing_file, sizeof(bs->auto_backing_file), | |
3679 | backing_hd->filename); | |
3680 | } | |
3681 | ||
5db15a57 KW |
3682 | /* Hook up the backing file link; drop our reference, bs owns the |
3683 | * backing_hd reference now */ | |
8aa04542 KW |
3684 | backing_hd_ctx = bdrv_get_aio_context(backing_hd); |
3685 | aio_context_acquire(backing_hd_ctx); | |
dc9c10a1 | 3686 | ret = bdrv_set_backing_hd(bs, backing_hd, errp); |
5db15a57 | 3687 | bdrv_unref(backing_hd); |
8aa04542 KW |
3688 | aio_context_release(backing_hd_ctx); |
3689 | ||
dc9c10a1 | 3690 | if (ret < 0) { |
12fa4af6 KW |
3691 | goto free_exit; |
3692 | } | |
d80ac658 | 3693 | |
d9b7b057 KW |
3694 | qdict_del(parent_options, bdref_key); |
3695 | ||
1ba4b6a5 BC |
3696 | free_exit: |
3697 | g_free(backing_filename); | |
cb3e7f08 | 3698 | qobject_unref(tmp_parent_options); |
1ba4b6a5 | 3699 | return ret; |
9156df12 PB |
3700 | } |
3701 | ||
2d6b86af KW |
3702 | static BlockDriverState * |
3703 | bdrv_open_child_bs(const char *filename, QDict *options, const char *bdref_key, | |
bd86fb99 | 3704 | BlockDriverState *parent, const BdrvChildClass *child_class, |
272c02ea | 3705 | BdrvChildRole child_role, bool allow_none, Error **errp) |
da557aac | 3706 | { |
2d6b86af | 3707 | BlockDriverState *bs = NULL; |
da557aac | 3708 | QDict *image_options; |
da557aac HR |
3709 | char *bdref_key_dot; |
3710 | const char *reference; | |
3711 | ||
bd86fb99 | 3712 | assert(child_class != NULL); |
f67503e5 | 3713 | |
da557aac HR |
3714 | bdref_key_dot = g_strdup_printf("%s.", bdref_key); |
3715 | qdict_extract_subqdict(options, &image_options, bdref_key_dot); | |
3716 | g_free(bdref_key_dot); | |
3717 | ||
129c7d1c MA |
3718 | /* |
3719 | * Caution: while qdict_get_try_str() is fine, getting non-string | |
3720 | * types would require more care. When @options come from | |
3721 | * -blockdev or blockdev_add, its members are typed according to | |
3722 | * the QAPI schema, but when they come from -drive, they're all | |
3723 | * QString. | |
3724 | */ | |
da557aac HR |
3725 | reference = qdict_get_try_str(options, bdref_key); |
3726 | if (!filename && !reference && !qdict_size(image_options)) { | |
b4b059f6 | 3727 | if (!allow_none) { |
da557aac HR |
3728 | error_setg(errp, "A block device must be specified for \"%s\"", |
3729 | bdref_key); | |
da557aac | 3730 | } |
cb3e7f08 | 3731 | qobject_unref(image_options); |
da557aac HR |
3732 | goto done; |
3733 | } | |
3734 | ||
5b363937 | 3735 | bs = bdrv_open_inherit(filename, reference, image_options, 0, |
272c02ea | 3736 | parent, child_class, child_role, errp); |
5b363937 | 3737 | if (!bs) { |
df581792 KW |
3738 | goto done; |
3739 | } | |
3740 | ||
da557aac HR |
3741 | done: |
3742 | qdict_del(options, bdref_key); | |
2d6b86af KW |
3743 | return bs; |
3744 | } | |
3745 | ||
3746 | /* | |
3747 | * Opens a disk image whose options are given as BlockdevRef in another block | |
3748 | * device's options. | |
3749 | * | |
3750 | * If allow_none is true, no image will be opened if filename is false and no | |
3751 | * BlockdevRef is given. NULL will be returned, but errp remains unset. | |
3752 | * | |
3753 | * bdrev_key specifies the key for the image's BlockdevRef in the options QDict. | |
3754 | * That QDict has to be flattened; therefore, if the BlockdevRef is a QDict | |
3755 | * itself, all options starting with "${bdref_key}." are considered part of the | |
3756 | * BlockdevRef. | |
3757 | * | |
3758 | * The BlockdevRef will be removed from the options QDict. | |
aa269ff8 | 3759 | * |
8394c35e | 3760 | * The caller must hold the lock of the main AioContext and no other AioContext. |
aa269ff8 KW |
3761 | * @parent can move to a different AioContext in this function. Callers must |
3762 | * make sure that their AioContext locking is still correct after this. | |
2d6b86af KW |
3763 | */ |
3764 | BdrvChild *bdrv_open_child(const char *filename, | |
3765 | QDict *options, const char *bdref_key, | |
3766 | BlockDriverState *parent, | |
bd86fb99 | 3767 | const BdrvChildClass *child_class, |
258b7765 | 3768 | BdrvChildRole child_role, |
2d6b86af KW |
3769 | bool allow_none, Error **errp) |
3770 | { | |
3771 | BlockDriverState *bs; | |
8394c35e KW |
3772 | BdrvChild *child; |
3773 | AioContext *ctx; | |
2d6b86af | 3774 | |
f791bf7f EGE |
3775 | GLOBAL_STATE_CODE(); |
3776 | ||
bd86fb99 | 3777 | bs = bdrv_open_child_bs(filename, options, bdref_key, parent, child_class, |
272c02ea | 3778 | child_role, allow_none, errp); |
2d6b86af KW |
3779 | if (bs == NULL) { |
3780 | return NULL; | |
3781 | } | |
3782 | ||
afdaeb9e | 3783 | bdrv_graph_wrlock(NULL); |
8394c35e KW |
3784 | ctx = bdrv_get_aio_context(bs); |
3785 | aio_context_acquire(ctx); | |
3786 | child = bdrv_attach_child(parent, bs, bdref_key, child_class, child_role, | |
3787 | errp); | |
3788 | aio_context_release(ctx); | |
afdaeb9e | 3789 | bdrv_graph_wrunlock(); |
8394c35e KW |
3790 | |
3791 | return child; | |
b4b059f6 KW |
3792 | } |
3793 | ||
83930780 VSO |
3794 | /* |
3795 | * Wrapper on bdrv_open_child() for most popular case: open primary child of bs. | |
aa269ff8 | 3796 | * |
8394c35e | 3797 | * The caller must hold the lock of the main AioContext and no other AioContext. |
aa269ff8 KW |
3798 | * @parent can move to a different AioContext in this function. Callers must |
3799 | * make sure that their AioContext locking is still correct after this. | |
83930780 VSO |
3800 | */ |
3801 | int bdrv_open_file_child(const char *filename, | |
3802 | QDict *options, const char *bdref_key, | |
3803 | BlockDriverState *parent, Error **errp) | |
3804 | { | |
3805 | BdrvChildRole role; | |
3806 | ||
3807 | /* commit_top and mirror_top don't use this function */ | |
3808 | assert(!parent->drv->filtered_child_is_backing); | |
83930780 VSO |
3809 | role = parent->drv->is_filter ? |
3810 | (BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY) : BDRV_CHILD_IMAGE; | |
3811 | ||
5bb04747 VSO |
3812 | if (!bdrv_open_child(filename, options, bdref_key, parent, |
3813 | &child_of_bds, role, false, errp)) | |
3814 | { | |
3815 | return -EINVAL; | |
3816 | } | |
83930780 | 3817 | |
5bb04747 | 3818 | return 0; |
83930780 VSO |
3819 | } |
3820 | ||
bd86fb99 HR |
3821 | /* |
3822 | * TODO Future callers may need to specify parent/child_class in order for | |
3823 | * option inheritance to work. Existing callers use it for the root node. | |
3824 | */ | |
e1d74bc6 KW |
3825 | BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp) |
3826 | { | |
3827 | BlockDriverState *bs = NULL; | |
e1d74bc6 KW |
3828 | QObject *obj = NULL; |
3829 | QDict *qdict = NULL; | |
3830 | const char *reference = NULL; | |
3831 | Visitor *v = NULL; | |
3832 | ||
f791bf7f EGE |
3833 | GLOBAL_STATE_CODE(); |
3834 | ||
e1d74bc6 KW |
3835 | if (ref->type == QTYPE_QSTRING) { |
3836 | reference = ref->u.reference; | |
3837 | } else { | |
3838 | BlockdevOptions *options = &ref->u.definition; | |
3839 | assert(ref->type == QTYPE_QDICT); | |
3840 | ||
3841 | v = qobject_output_visitor_new(&obj); | |
1f584248 | 3842 | visit_type_BlockdevOptions(v, NULL, &options, &error_abort); |
e1d74bc6 KW |
3843 | visit_complete(v, &obj); |
3844 | ||
7dc847eb | 3845 | qdict = qobject_to(QDict, obj); |
e1d74bc6 KW |
3846 | qdict_flatten(qdict); |
3847 | ||
3848 | /* bdrv_open_inherit() defaults to the values in bdrv_flags (for | |
3849 | * compatibility with other callers) rather than what we want as the | |
3850 | * real defaults. Apply the defaults here instead. */ | |
3851 | qdict_set_default_str(qdict, BDRV_OPT_CACHE_DIRECT, "off"); | |
3852 | qdict_set_default_str(qdict, BDRV_OPT_CACHE_NO_FLUSH, "off"); | |
3853 | qdict_set_default_str(qdict, BDRV_OPT_READ_ONLY, "off"); | |
e35bdc12 KW |
3854 | qdict_set_default_str(qdict, BDRV_OPT_AUTO_READ_ONLY, "off"); |
3855 | ||
e1d74bc6 KW |
3856 | } |
3857 | ||
272c02ea | 3858 | bs = bdrv_open_inherit(NULL, reference, qdict, 0, NULL, NULL, 0, errp); |
e1d74bc6 | 3859 | obj = NULL; |
cb3e7f08 | 3860 | qobject_unref(obj); |
e1d74bc6 KW |
3861 | visit_free(v); |
3862 | return bs; | |
3863 | } | |
3864 | ||
66836189 HR |
3865 | static BlockDriverState *bdrv_append_temp_snapshot(BlockDriverState *bs, |
3866 | int flags, | |
3867 | QDict *snapshot_options, | |
3868 | Error **errp) | |
b998875d | 3869 | { |
69fbfff9 | 3870 | g_autofree char *tmp_filename = NULL; |
b998875d | 3871 | int64_t total_size; |
83d0521a | 3872 | QemuOpts *opts = NULL; |
ff6ed714 | 3873 | BlockDriverState *bs_snapshot = NULL; |
f665f01f | 3874 | AioContext *ctx = bdrv_get_aio_context(bs); |
b998875d KW |
3875 | int ret; |
3876 | ||
bdb73476 EGE |
3877 | GLOBAL_STATE_CODE(); |
3878 | ||
b998875d KW |
3879 | /* if snapshot, we create a temporary backing file and open it |
3880 | instead of opening 'filename' directly */ | |
3881 | ||
3882 | /* Get the required size from the image */ | |
f665f01f | 3883 | aio_context_acquire(ctx); |
f187743a | 3884 | total_size = bdrv_getlength(bs); |
f665f01f KW |
3885 | aio_context_release(ctx); |
3886 | ||
f187743a KW |
3887 | if (total_size < 0) { |
3888 | error_setg_errno(errp, -total_size, "Could not get image size"); | |
1ba4b6a5 | 3889 | goto out; |
f187743a | 3890 | } |
b998875d KW |
3891 | |
3892 | /* Create the temporary image */ | |
69fbfff9 BM |
3893 | tmp_filename = create_tmp_file(errp); |
3894 | if (!tmp_filename) { | |
1ba4b6a5 | 3895 | goto out; |
b998875d KW |
3896 | } |
3897 | ||
ef810437 | 3898 | opts = qemu_opts_create(bdrv_qcow2.create_opts, NULL, 0, |
c282e1fd | 3899 | &error_abort); |
39101f25 | 3900 | qemu_opt_set_number(opts, BLOCK_OPT_SIZE, total_size, &error_abort); |
e43bfd9c | 3901 | ret = bdrv_create(&bdrv_qcow2, tmp_filename, opts, errp); |
83d0521a | 3902 | qemu_opts_del(opts); |
b998875d | 3903 | if (ret < 0) { |
e43bfd9c MA |
3904 | error_prepend(errp, "Could not create temporary overlay '%s': ", |
3905 | tmp_filename); | |
1ba4b6a5 | 3906 | goto out; |
b998875d KW |
3907 | } |
3908 | ||
73176bee | 3909 | /* Prepare options QDict for the temporary file */ |
46f5ac20 EB |
3910 | qdict_put_str(snapshot_options, "file.driver", "file"); |
3911 | qdict_put_str(snapshot_options, "file.filename", tmp_filename); | |
3912 | qdict_put_str(snapshot_options, "driver", "qcow2"); | |
b998875d | 3913 | |
5b363937 | 3914 | bs_snapshot = bdrv_open(NULL, NULL, snapshot_options, flags, errp); |
73176bee | 3915 | snapshot_options = NULL; |
5b363937 | 3916 | if (!bs_snapshot) { |
1ba4b6a5 | 3917 | goto out; |
b998875d KW |
3918 | } |
3919 | ||
f665f01f | 3920 | aio_context_acquire(ctx); |
934aee14 | 3921 | ret = bdrv_append(bs_snapshot, bs, errp); |
f665f01f KW |
3922 | aio_context_release(ctx); |
3923 | ||
934aee14 | 3924 | if (ret < 0) { |
ff6ed714 | 3925 | bs_snapshot = NULL; |
b2c2832c KW |
3926 | goto out; |
3927 | } | |
1ba4b6a5 BC |
3928 | |
3929 | out: | |
cb3e7f08 | 3930 | qobject_unref(snapshot_options); |
ff6ed714 | 3931 | return bs_snapshot; |
b998875d KW |
3932 | } |
3933 | ||
b6ce07aa KW |
3934 | /* |
3935 | * Opens a disk image (raw, qcow2, vmdk, ...) | |
de9c0cec KW |
3936 | * |
3937 | * options is a QDict of options to pass to the block drivers, or NULL for an | |
3938 | * empty set of options. The reference to the QDict belongs to the block layer | |
3939 | * after the call (even on failure), so if the caller intends to reuse the | |
cb3e7f08 | 3940 | * dictionary, it needs to use qobject_ref() before calling bdrv_open. |
f67503e5 HR |
3941 | * |
3942 | * If *pbs is NULL, a new BDS will be created with a pointer to it stored there. | |
3943 | * If it is not NULL, the referenced BDS will be reused. | |
ddf5636d HR |
3944 | * |
3945 | * The reference parameter may be used to specify an existing block device which | |
3946 | * should be opened. If specified, neither options nor a filename may be given, | |
3947 | * nor can an existing BDS be reused (that is, *pbs has to be NULL). | |
c86422c5 | 3948 | * |
ae400dbb | 3949 | * The caller must always hold the main AioContext lock. |
b6ce07aa | 3950 | */ |
32192301 KW |
3951 | static BlockDriverState * no_coroutine_fn |
3952 | bdrv_open_inherit(const char *filename, const char *reference, QDict *options, | |
3953 | int flags, BlockDriverState *parent, | |
3954 | const BdrvChildClass *child_class, BdrvChildRole child_role, | |
3955 | Error **errp) | |
ea2384d3 | 3956 | { |
b6ce07aa | 3957 | int ret; |
5696c6e3 | 3958 | BlockBackend *file = NULL; |
9a4f4c31 | 3959 | BlockDriverState *bs; |
ce343771 | 3960 | BlockDriver *drv = NULL; |
2f624b80 | 3961 | BdrvChild *child; |
74fe54f2 | 3962 | const char *drvname; |
3e8c2e57 | 3963 | const char *backing; |
34b5d2c6 | 3964 | Error *local_err = NULL; |
73176bee | 3965 | QDict *snapshot_options = NULL; |
b1e6fc08 | 3966 | int snapshot_flags = 0; |
f665f01f | 3967 | AioContext *ctx = qemu_get_aio_context(); |
712e7874 | 3968 | |
bd86fb99 HR |
3969 | assert(!child_class || !flags); |
3970 | assert(!child_class == !parent); | |
f0c28327 | 3971 | GLOBAL_STATE_CODE(); |
32192301 | 3972 | assert(!qemu_in_coroutine()); |
f67503e5 | 3973 | |
356f4ef6 KW |
3974 | /* TODO We'll eventually have to take a writer lock in this function */ |
3975 | GRAPH_RDLOCK_GUARD_MAINLOOP(); | |
3976 | ||
ddf5636d HR |
3977 | if (reference) { |
3978 | bool options_non_empty = options ? qdict_size(options) : false; | |
cb3e7f08 | 3979 | qobject_unref(options); |
ddf5636d | 3980 | |
ddf5636d HR |
3981 | if (filename || options_non_empty) { |
3982 | error_setg(errp, "Cannot reference an existing block device with " | |
3983 | "additional options or a new filename"); | |
5b363937 | 3984 | return NULL; |
ddf5636d HR |
3985 | } |
3986 | ||
3987 | bs = bdrv_lookup_bs(reference, reference, errp); | |
3988 | if (!bs) { | |
5b363937 | 3989 | return NULL; |
ddf5636d | 3990 | } |
76b22320 | 3991 | |
ddf5636d | 3992 | bdrv_ref(bs); |
5b363937 | 3993 | return bs; |
ddf5636d HR |
3994 | } |
3995 | ||
5b363937 | 3996 | bs = bdrv_new(); |
f67503e5 | 3997 | |
de9c0cec KW |
3998 | /* NULL means an empty set of options */ |
3999 | if (options == NULL) { | |
4000 | options = qdict_new(); | |
4001 | } | |
4002 | ||
145f598e | 4003 | /* json: syntax counts as explicit options, as if in the QDict */ |
de3b53f0 KW |
4004 | parse_json_protocol(options, &filename, &local_err); |
4005 | if (local_err) { | |
de3b53f0 KW |
4006 | goto fail; |
4007 | } | |
4008 | ||
145f598e KW |
4009 | bs->explicit_options = qdict_clone_shallow(options); |
4010 | ||
bd86fb99 | 4011 | if (child_class) { |
3cdc69d3 HR |
4012 | bool parent_is_format; |
4013 | ||
4014 | if (parent->drv) { | |
4015 | parent_is_format = parent->drv->is_format; | |
4016 | } else { | |
4017 | /* | |
4018 | * parent->drv is not set yet because this node is opened for | |
4019 | * (potential) format probing. That means that @parent is going | |
4020 | * to be a format node. | |
4021 | */ | |
4022 | parent_is_format = true; | |
4023 | } | |
4024 | ||
bddcec37 | 4025 | bs->inherits_from = parent; |
3cdc69d3 HR |
4026 | child_class->inherit_options(child_role, parent_is_format, |
4027 | &flags, options, | |
bd86fb99 | 4028 | parent->open_flags, parent->options); |
f3930ed0 KW |
4029 | } |
4030 | ||
de3b53f0 | 4031 | ret = bdrv_fill_options(&options, filename, &flags, &local_err); |
dfde483e | 4032 | if (ret < 0) { |
462f5bcf KW |
4033 | goto fail; |
4034 | } | |
4035 | ||
129c7d1c MA |
4036 | /* |
4037 | * Set the BDRV_O_RDWR and BDRV_O_ALLOW_RDWR flags. | |
4038 | * Caution: getting a boolean member of @options requires care. | |
4039 | * When @options come from -blockdev or blockdev_add, members are | |
4040 | * typed according to the QAPI schema, but when they come from | |
4041 | * -drive, they're all QString. | |
4042 | */ | |
f87a0e29 AG |
4043 | if (g_strcmp0(qdict_get_try_str(options, BDRV_OPT_READ_ONLY), "on") && |
4044 | !qdict_get_try_bool(options, BDRV_OPT_READ_ONLY, false)) { | |
4045 | flags |= (BDRV_O_RDWR | BDRV_O_ALLOW_RDWR); | |
4046 | } else { | |
4047 | flags &= ~BDRV_O_RDWR; | |
14499ea5 AG |
4048 | } |
4049 | ||
4050 | if (flags & BDRV_O_SNAPSHOT) { | |
4051 | snapshot_options = qdict_new(); | |
4052 | bdrv_temp_snapshot_options(&snapshot_flags, snapshot_options, | |
4053 | flags, options); | |
f87a0e29 AG |
4054 | /* Let bdrv_backing_options() override "read-only" */ |
4055 | qdict_del(options, BDRV_OPT_READ_ONLY); | |
00ff7ffd HR |
4056 | bdrv_inherited_options(BDRV_CHILD_COW, true, |
4057 | &flags, options, flags, options); | |
14499ea5 AG |
4058 | } |
4059 | ||
62392ebb KW |
4060 | bs->open_flags = flags; |
4061 | bs->options = options; | |
4062 | options = qdict_clone_shallow(options); | |
4063 | ||
76c591b0 | 4064 | /* Find the right image format driver */ |
129c7d1c | 4065 | /* See cautionary note on accessing @options above */ |
76c591b0 KW |
4066 | drvname = qdict_get_try_str(options, "driver"); |
4067 | if (drvname) { | |
4068 | drv = bdrv_find_format(drvname); | |
76c591b0 KW |
4069 | if (!drv) { |
4070 | error_setg(errp, "Unknown driver: '%s'", drvname); | |
76c591b0 KW |
4071 | goto fail; |
4072 | } | |
4073 | } | |
4074 | ||
4075 | assert(drvname || !(flags & BDRV_O_PROTOCOL)); | |
76c591b0 | 4076 | |
129c7d1c | 4077 | /* See cautionary note on accessing @options above */ |
3e8c2e57 | 4078 | backing = qdict_get_try_str(options, "backing"); |
e59a0cf1 HR |
4079 | if (qobject_to(QNull, qdict_get(options, "backing")) != NULL || |
4080 | (backing && *backing == '\0')) | |
4081 | { | |
4f7be280 HR |
4082 | if (backing) { |
4083 | warn_report("Use of \"backing\": \"\" is deprecated; " | |
4084 | "use \"backing\": null instead"); | |
4085 | } | |
3e8c2e57 | 4086 | flags |= BDRV_O_NO_BACKING; |
ae0f57f0 KW |
4087 | qdict_del(bs->explicit_options, "backing"); |
4088 | qdict_del(bs->options, "backing"); | |
3e8c2e57 AG |
4089 | qdict_del(options, "backing"); |
4090 | } | |
4091 | ||
5696c6e3 | 4092 | /* Open image file without format layer. This BlockBackend is only used for |
4e4bf5c4 KW |
4093 | * probing, the block drivers will do their own bdrv_open_child() for the |
4094 | * same BDS, which is why we put the node name back into options. */ | |
f4788adc | 4095 | if ((flags & BDRV_O_PROTOCOL) == 0) { |
5696c6e3 KW |
4096 | BlockDriverState *file_bs; |
4097 | ||
4098 | file_bs = bdrv_open_child_bs(filename, options, "file", bs, | |
58944401 HR |
4099 | &child_of_bds, BDRV_CHILD_IMAGE, |
4100 | true, &local_err); | |
1fdd6933 | 4101 | if (local_err) { |
f4788adc KW |
4102 | goto fail; |
4103 | } | |
5696c6e3 | 4104 | if (file_bs != NULL) { |
dacaa162 KW |
4105 | /* Not requesting BLK_PERM_CONSISTENT_READ because we're only |
4106 | * looking at the header to guess the image format. This works even | |
4107 | * in cases where a guest would not see a consistent state. */ | |
f665f01f KW |
4108 | ctx = bdrv_get_aio_context(file_bs); |
4109 | aio_context_acquire(ctx); | |
4110 | file = blk_new(ctx, 0, BLK_PERM_ALL); | |
d7086422 | 4111 | blk_insert_bs(file, file_bs, &local_err); |
5696c6e3 | 4112 | bdrv_unref(file_bs); |
f665f01f KW |
4113 | aio_context_release(ctx); |
4114 | ||
d7086422 KW |
4115 | if (local_err) { |
4116 | goto fail; | |
4117 | } | |
5696c6e3 | 4118 | |
46f5ac20 | 4119 | qdict_put_str(options, "file", bdrv_get_node_name(file_bs)); |
4e4bf5c4 | 4120 | } |
f500a6d3 KW |
4121 | } |
4122 | ||
76c591b0 | 4123 | /* Image format probing */ |
38f3ef57 | 4124 | bs->probed = !drv; |
76c591b0 | 4125 | if (!drv && file) { |
cf2ab8fc | 4126 | ret = find_image_format(file, filename, &drv, &local_err); |
17b005f1 | 4127 | if (ret < 0) { |
8bfea15d | 4128 | goto fail; |
2a05cbe4 | 4129 | } |
62392ebb KW |
4130 | /* |
4131 | * This option update would logically belong in bdrv_fill_options(), | |
4132 | * but we first need to open bs->file for the probing to work, while | |
4133 | * opening bs->file already requires the (mostly) final set of options | |
4134 | * so that cache mode etc. can be inherited. | |
4135 | * | |
4136 | * Adding the driver later is somewhat ugly, but it's not an option | |
4137 | * that would ever be inherited, so it's correct. We just need to make | |
4138 | * sure to update both bs->options (which has the full effective | |
4139 | * options for bs) and options (which has file.* already removed). | |
4140 | */ | |
46f5ac20 EB |
4141 | qdict_put_str(bs->options, "driver", drv->format_name); |
4142 | qdict_put_str(options, "driver", drv->format_name); | |
76c591b0 | 4143 | } else if (!drv) { |
17b005f1 | 4144 | error_setg(errp, "Must specify either driver or file"); |
8bfea15d | 4145 | goto fail; |
ea2384d3 | 4146 | } |
b6ce07aa | 4147 | |
53a29513 HR |
4148 | /* BDRV_O_PROTOCOL must be set iff a protocol BDS is about to be created */ |
4149 | assert(!!(flags & BDRV_O_PROTOCOL) == !!drv->bdrv_file_open); | |
4150 | /* file must be NULL if a protocol BDS is about to be created | |
4151 | * (the inverse results in an error message from bdrv_open_common()) */ | |
4152 | assert(!(flags & BDRV_O_PROTOCOL) || !file); | |
4153 | ||
b6ce07aa | 4154 | /* Open the image */ |
82dc8b41 | 4155 | ret = bdrv_open_common(bs, file, options, &local_err); |
b6ce07aa | 4156 | if (ret < 0) { |
8bfea15d | 4157 | goto fail; |
6987307c CH |
4158 | } |
4159 | ||
f665f01f KW |
4160 | /* The AioContext could have changed during bdrv_open_common() */ |
4161 | ctx = bdrv_get_aio_context(bs); | |
4162 | ||
4e4bf5c4 | 4163 | if (file) { |
f665f01f | 4164 | aio_context_acquire(ctx); |
5696c6e3 | 4165 | blk_unref(file); |
f665f01f | 4166 | aio_context_release(ctx); |
f500a6d3 KW |
4167 | file = NULL; |
4168 | } | |
4169 | ||
b6ce07aa | 4170 | /* If there is a backing file, use it */ |
9156df12 | 4171 | if ((flags & BDRV_O_NO_BACKING) == 0) { |
d9b7b057 | 4172 | ret = bdrv_open_backing_file(bs, options, "backing", &local_err); |
b6ce07aa | 4173 | if (ret < 0) { |
b6ad491a | 4174 | goto close_and_fail; |
b6ce07aa | 4175 | } |
b6ce07aa KW |
4176 | } |
4177 | ||
50196d7a AG |
4178 | /* Remove all children options and references |
4179 | * from bs->options and bs->explicit_options */ | |
2f624b80 AG |
4180 | QLIST_FOREACH(child, &bs->children, next) { |
4181 | char *child_key_dot; | |
4182 | child_key_dot = g_strdup_printf("%s.", child->name); | |
4183 | qdict_extract_subqdict(bs->explicit_options, NULL, child_key_dot); | |
4184 | qdict_extract_subqdict(bs->options, NULL, child_key_dot); | |
50196d7a AG |
4185 | qdict_del(bs->explicit_options, child->name); |
4186 | qdict_del(bs->options, child->name); | |
2f624b80 AG |
4187 | g_free(child_key_dot); |
4188 | } | |
4189 | ||
b6ad491a | 4190 | /* Check if any unknown options were used */ |
7ad2757f | 4191 | if (qdict_size(options) != 0) { |
b6ad491a | 4192 | const QDictEntry *entry = qdict_first(options); |
5acd9d81 HR |
4193 | if (flags & BDRV_O_PROTOCOL) { |
4194 | error_setg(errp, "Block protocol '%s' doesn't support the option " | |
4195 | "'%s'", drv->format_name, entry->key); | |
4196 | } else { | |
d0e46a55 HR |
4197 | error_setg(errp, |
4198 | "Block format '%s' does not support the option '%s'", | |
4199 | drv->format_name, entry->key); | |
5acd9d81 | 4200 | } |
b6ad491a | 4201 | |
b6ad491a KW |
4202 | goto close_and_fail; |
4203 | } | |
b6ad491a | 4204 | |
c01c214b | 4205 | bdrv_parent_cb_change_media(bs, true); |
b6ce07aa | 4206 | |
cb3e7f08 | 4207 | qobject_unref(options); |
8961be33 | 4208 | options = NULL; |
dd62f1ca KW |
4209 | |
4210 | /* For snapshot=on, create a temporary qcow2 overlay. bs points to the | |
4211 | * temporary snapshot afterwards. */ | |
4212 | if (snapshot_flags) { | |
66836189 HR |
4213 | BlockDriverState *snapshot_bs; |
4214 | snapshot_bs = bdrv_append_temp_snapshot(bs, snapshot_flags, | |
4215 | snapshot_options, &local_err); | |
73176bee | 4216 | snapshot_options = NULL; |
dd62f1ca KW |
4217 | if (local_err) { |
4218 | goto close_and_fail; | |
4219 | } | |
5b363937 HR |
4220 | /* We are not going to return bs but the overlay on top of it |
4221 | * (snapshot_bs); thus, we have to drop the strong reference to bs | |
4222 | * (which we obtained by calling bdrv_new()). bs will not be deleted, | |
4223 | * though, because the overlay still has a reference to it. */ | |
f665f01f | 4224 | aio_context_acquire(ctx); |
5b363937 | 4225 | bdrv_unref(bs); |
f665f01f | 4226 | aio_context_release(ctx); |
5b363937 | 4227 | bs = snapshot_bs; |
dd62f1ca KW |
4228 | } |
4229 | ||
5b363937 | 4230 | return bs; |
b6ce07aa | 4231 | |
8bfea15d | 4232 | fail: |
f665f01f | 4233 | aio_context_acquire(ctx); |
5696c6e3 | 4234 | blk_unref(file); |
cb3e7f08 MAL |
4235 | qobject_unref(snapshot_options); |
4236 | qobject_unref(bs->explicit_options); | |
4237 | qobject_unref(bs->options); | |
4238 | qobject_unref(options); | |
de9c0cec | 4239 | bs->options = NULL; |
998cbd6a | 4240 | bs->explicit_options = NULL; |
5b363937 | 4241 | bdrv_unref(bs); |
f665f01f | 4242 | aio_context_release(ctx); |
621ff94d | 4243 | error_propagate(errp, local_err); |
5b363937 | 4244 | return NULL; |
de9c0cec | 4245 | |
b6ad491a | 4246 | close_and_fail: |
f665f01f | 4247 | aio_context_acquire(ctx); |
5b363937 | 4248 | bdrv_unref(bs); |
f665f01f | 4249 | aio_context_release(ctx); |
cb3e7f08 MAL |
4250 | qobject_unref(snapshot_options); |
4251 | qobject_unref(options); | |
621ff94d | 4252 | error_propagate(errp, local_err); |
5b363937 | 4253 | return NULL; |
b6ce07aa KW |
4254 | } |
4255 | ||
ae400dbb | 4256 | /* The caller must always hold the main AioContext lock. */ |
5b363937 HR |
4257 | BlockDriverState *bdrv_open(const char *filename, const char *reference, |
4258 | QDict *options, int flags, Error **errp) | |
f3930ed0 | 4259 | { |
f791bf7f EGE |
4260 | GLOBAL_STATE_CODE(); |
4261 | ||
5b363937 | 4262 | return bdrv_open_inherit(filename, reference, options, flags, NULL, |
272c02ea | 4263 | NULL, 0, errp); |
f3930ed0 KW |
4264 | } |
4265 | ||
faf116b4 AG |
4266 | /* Return true if the NULL-terminated @list contains @str */ |
4267 | static bool is_str_in_list(const char *str, const char *const *list) | |
4268 | { | |
4269 | if (str && list) { | |
4270 | int i; | |
4271 | for (i = 0; list[i] != NULL; i++) { | |
4272 | if (!strcmp(str, list[i])) { | |
4273 | return true; | |
4274 | } | |
4275 | } | |
4276 | } | |
4277 | return false; | |
4278 | } | |
4279 | ||
4280 | /* | |
4281 | * Check that every option set in @bs->options is also set in | |
4282 | * @new_opts. | |
4283 | * | |
4284 | * Options listed in the common_options list and in | |
4285 | * @bs->drv->mutable_opts are skipped. | |
4286 | * | |
4287 | * Return 0 on success, otherwise return -EINVAL and set @errp. | |
4288 | */ | |
4289 | static int bdrv_reset_options_allowed(BlockDriverState *bs, | |
4290 | const QDict *new_opts, Error **errp) | |
4291 | { | |
4292 | const QDictEntry *e; | |
4293 | /* These options are common to all block drivers and are handled | |
4294 | * in bdrv_reopen_prepare() so they can be left out of @new_opts */ | |
4295 | const char *const common_options[] = { | |
4296 | "node-name", "discard", "cache.direct", "cache.no-flush", | |
4297 | "read-only", "auto-read-only", "detect-zeroes", NULL | |
4298 | }; | |
4299 | ||
4300 | for (e = qdict_first(bs->options); e; e = qdict_next(bs->options, e)) { | |
4301 | if (!qdict_haskey(new_opts, e->key) && | |
4302 | !is_str_in_list(e->key, common_options) && | |
4303 | !is_str_in_list(e->key, bs->drv->mutable_opts)) { | |
4304 | error_setg(errp, "Option '%s' cannot be reset " | |
4305 | "to its default value", e->key); | |
4306 | return -EINVAL; | |
4307 | } | |
4308 | } | |
4309 | ||
4310 | return 0; | |
4311 | } | |
4312 | ||
cb828c31 AG |
4313 | /* |
4314 | * Returns true if @child can be reached recursively from @bs | |
4315 | */ | |
4316 | static bool bdrv_recurse_has_child(BlockDriverState *bs, | |
4317 | BlockDriverState *child) | |
4318 | { | |
4319 | BdrvChild *c; | |
4320 | ||
4321 | if (bs == child) { | |
4322 | return true; | |
4323 | } | |
4324 | ||
4325 | QLIST_FOREACH(c, &bs->children, next) { | |
4326 | if (bdrv_recurse_has_child(c->bs, child)) { | |
4327 | return true; | |
4328 | } | |
4329 | } | |
4330 | ||
4331 | return false; | |
4332 | } | |
4333 | ||
e971aa12 JC |
4334 | /* |
4335 | * Adds a BlockDriverState to a simple queue for an atomic, transactional | |
4336 | * reopen of multiple devices. | |
4337 | * | |
859443b0 | 4338 | * bs_queue can either be an existing BlockReopenQueue that has had QTAILQ_INIT |
e971aa12 JC |
4339 | * already performed, or alternatively may be NULL a new BlockReopenQueue will |
4340 | * be created and initialized. This newly created BlockReopenQueue should be | |
4341 | * passed back in for subsequent calls that are intended to be of the same | |
4342 | * atomic 'set'. | |
4343 | * | |
4344 | * bs is the BlockDriverState to add to the reopen queue. | |
4345 | * | |
4d2cb092 KW |
4346 | * options contains the changed options for the associated bs |
4347 | * (the BlockReopenQueue takes ownership) | |
4348 | * | |
e971aa12 JC |
4349 | * flags contains the open flags for the associated bs |
4350 | * | |
4351 | * returns a pointer to bs_queue, which is either the newly allocated | |
4352 | * bs_queue, or the existing bs_queue being used. | |
4353 | * | |
d22933ac | 4354 | * bs is drained here and undrained by bdrv_reopen_queue_free(). |
2e117866 KW |
4355 | * |
4356 | * To be called with bs->aio_context locked. | |
e971aa12 | 4357 | */ |
28518102 KW |
4358 | static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue, |
4359 | BlockDriverState *bs, | |
4360 | QDict *options, | |
bd86fb99 | 4361 | const BdrvChildClass *klass, |
272c02ea | 4362 | BdrvChildRole role, |
3cdc69d3 | 4363 | bool parent_is_format, |
28518102 | 4364 | QDict *parent_options, |
077e8e20 AG |
4365 | int parent_flags, |
4366 | bool keep_old_opts) | |
e971aa12 JC |
4367 | { |
4368 | assert(bs != NULL); | |
4369 | ||
4370 | BlockReopenQueueEntry *bs_entry; | |
67251a31 | 4371 | BdrvChild *child; |
9aa09ddd AG |
4372 | QDict *old_options, *explicit_options, *options_copy; |
4373 | int flags; | |
4374 | QemuOpts *opts; | |
67251a31 | 4375 | |
f0c28327 | 4376 | GLOBAL_STATE_CODE(); |
1a63a907 | 4377 | |
d22933ac KW |
4378 | bdrv_drained_begin(bs); |
4379 | ||
e971aa12 JC |
4380 | if (bs_queue == NULL) { |
4381 | bs_queue = g_new0(BlockReopenQueue, 1); | |
859443b0 | 4382 | QTAILQ_INIT(bs_queue); |
e971aa12 JC |
4383 | } |
4384 | ||
4d2cb092 KW |
4385 | if (!options) { |
4386 | options = qdict_new(); | |
4387 | } | |
4388 | ||
5b7ba05f | 4389 | /* Check if this BlockDriverState is already in the queue */ |
859443b0 | 4390 | QTAILQ_FOREACH(bs_entry, bs_queue, entry) { |
5b7ba05f AG |
4391 | if (bs == bs_entry->state.bs) { |
4392 | break; | |
4393 | } | |
4394 | } | |
4395 | ||
28518102 KW |
4396 | /* |
4397 | * Precedence of options: | |
4398 | * 1. Explicitly passed in options (highest) | |
9aa09ddd AG |
4399 | * 2. Retained from explicitly set options of bs |
4400 | * 3. Inherited from parent node | |
4401 | * 4. Retained from effective options of bs | |
28518102 KW |
4402 | */ |
4403 | ||
145f598e | 4404 | /* Old explicitly set values (don't overwrite by inherited value) */ |
077e8e20 AG |
4405 | if (bs_entry || keep_old_opts) { |
4406 | old_options = qdict_clone_shallow(bs_entry ? | |
4407 | bs_entry->state.explicit_options : | |
4408 | bs->explicit_options); | |
4409 | bdrv_join_options(bs, options, old_options); | |
4410 | qobject_unref(old_options); | |
5b7ba05f | 4411 | } |
145f598e KW |
4412 | |
4413 | explicit_options = qdict_clone_shallow(options); | |
4414 | ||
28518102 KW |
4415 | /* Inherit from parent node */ |
4416 | if (parent_options) { | |
9aa09ddd | 4417 | flags = 0; |
3cdc69d3 | 4418 | klass->inherit_options(role, parent_is_format, &flags, options, |
272c02ea | 4419 | parent_flags, parent_options); |
9aa09ddd AG |
4420 | } else { |
4421 | flags = bdrv_get_flags(bs); | |
28518102 KW |
4422 | } |
4423 | ||
077e8e20 AG |
4424 | if (keep_old_opts) { |
4425 | /* Old values are used for options that aren't set yet */ | |
4426 | old_options = qdict_clone_shallow(bs->options); | |
4427 | bdrv_join_options(bs, options, old_options); | |
4428 | qobject_unref(old_options); | |
4429 | } | |
4d2cb092 | 4430 | |
9aa09ddd AG |
4431 | /* We have the final set of options so let's update the flags */ |
4432 | options_copy = qdict_clone_shallow(options); | |
4433 | opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort); | |
4434 | qemu_opts_absorb_qdict(opts, options_copy, NULL); | |
4435 | update_flags_from_options(&flags, opts); | |
4436 | qemu_opts_del(opts); | |
4437 | qobject_unref(options_copy); | |
4438 | ||
fd452021 | 4439 | /* bdrv_open_inherit() sets and clears some additional flags internally */ |
f1f25a2e | 4440 | flags &= ~BDRV_O_PROTOCOL; |
fd452021 KW |
4441 | if (flags & BDRV_O_RDWR) { |
4442 | flags |= BDRV_O_ALLOW_RDWR; | |
4443 | } | |
f1f25a2e | 4444 | |
1857c97b KW |
4445 | if (!bs_entry) { |
4446 | bs_entry = g_new0(BlockReopenQueueEntry, 1); | |
859443b0 | 4447 | QTAILQ_INSERT_TAIL(bs_queue, bs_entry, entry); |
1857c97b | 4448 | } else { |
cb3e7f08 MAL |
4449 | qobject_unref(bs_entry->state.options); |
4450 | qobject_unref(bs_entry->state.explicit_options); | |
1857c97b KW |
4451 | } |
4452 | ||
4453 | bs_entry->state.bs = bs; | |
4454 | bs_entry->state.options = options; | |
4455 | bs_entry->state.explicit_options = explicit_options; | |
4456 | bs_entry->state.flags = flags; | |
4457 | ||
8546632e AG |
4458 | /* |
4459 | * If keep_old_opts is false then it means that unspecified | |
4460 | * options must be reset to their original value. We don't allow | |
4461 | * resetting 'backing' but we need to know if the option is | |
4462 | * missing in order to decide if we have to return an error. | |
4463 | */ | |
4464 | if (!keep_old_opts) { | |
4465 | bs_entry->state.backing_missing = | |
4466 | !qdict_haskey(options, "backing") && | |
4467 | !qdict_haskey(options, "backing.driver"); | |
4468 | } | |
4469 | ||
67251a31 | 4470 | QLIST_FOREACH(child, &bs->children, next) { |
8546632e AG |
4471 | QDict *new_child_options = NULL; |
4472 | bool child_keep_old = keep_old_opts; | |
67251a31 | 4473 | |
4c9dfe5d KW |
4474 | /* reopen can only change the options of block devices that were |
4475 | * implicitly created and inherited options. For other (referenced) | |
4476 | * block devices, a syntax like "backing.foo" results in an error. */ | |
67251a31 KW |
4477 | if (child->bs->inherits_from != bs) { |
4478 | continue; | |
4479 | } | |
4480 | ||
8546632e AG |
4481 | /* Check if the options contain a child reference */ |
4482 | if (qdict_haskey(options, child->name)) { | |
4483 | const char *childref = qdict_get_try_str(options, child->name); | |
4484 | /* | |
4485 | * The current child must not be reopened if the child | |
4486 | * reference is null or points to a different node. | |
4487 | */ | |
4488 | if (g_strcmp0(childref, child->bs->node_name)) { | |
4489 | continue; | |
4490 | } | |
4491 | /* | |
4492 | * If the child reference points to the current child then | |
4493 | * reopen it with its existing set of options (note that | |
4494 | * it can still inherit new options from the parent). | |
4495 | */ | |
4496 | child_keep_old = true; | |
4497 | } else { | |
4498 | /* Extract child options ("child-name.*") */ | |
4499 | char *child_key_dot = g_strdup_printf("%s.", child->name); | |
4500 | qdict_extract_subqdict(explicit_options, NULL, child_key_dot); | |
4501 | qdict_extract_subqdict(options, &new_child_options, child_key_dot); | |
4502 | g_free(child_key_dot); | |
4503 | } | |
4c9dfe5d | 4504 | |
9aa09ddd | 4505 | bdrv_reopen_queue_child(bs_queue, child->bs, new_child_options, |
3cdc69d3 HR |
4506 | child->klass, child->role, bs->drv->is_format, |
4507 | options, flags, child_keep_old); | |
e971aa12 JC |
4508 | } |
4509 | ||
e971aa12 JC |
4510 | return bs_queue; |
4511 | } | |
4512 | ||
2e117866 | 4513 | /* To be called with bs->aio_context locked */ |
28518102 KW |
4514 | BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, |
4515 | BlockDriverState *bs, | |
077e8e20 | 4516 | QDict *options, bool keep_old_opts) |
28518102 | 4517 | { |
f791bf7f EGE |
4518 | GLOBAL_STATE_CODE(); |
4519 | ||
3cdc69d3 HR |
4520 | return bdrv_reopen_queue_child(bs_queue, bs, options, NULL, 0, false, |
4521 | NULL, 0, keep_old_opts); | |
28518102 KW |
4522 | } |
4523 | ||
ab5b5228 AG |
4524 | void bdrv_reopen_queue_free(BlockReopenQueue *bs_queue) |
4525 | { | |
f791bf7f | 4526 | GLOBAL_STATE_CODE(); |
ab5b5228 AG |
4527 | if (bs_queue) { |
4528 | BlockReopenQueueEntry *bs_entry, *next; | |
4529 | QTAILQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) { | |
d22933ac KW |
4530 | AioContext *ctx = bdrv_get_aio_context(bs_entry->state.bs); |
4531 | ||
4532 | aio_context_acquire(ctx); | |
4533 | bdrv_drained_end(bs_entry->state.bs); | |
4534 | aio_context_release(ctx); | |
4535 | ||
ab5b5228 AG |
4536 | qobject_unref(bs_entry->state.explicit_options); |
4537 | qobject_unref(bs_entry->state.options); | |
4538 | g_free(bs_entry); | |
4539 | } | |
4540 | g_free(bs_queue); | |
4541 | } | |
4542 | } | |
4543 | ||
e971aa12 JC |
4544 | /* |
4545 | * Reopen multiple BlockDriverStates atomically & transactionally. | |
4546 | * | |
4547 | * The queue passed in (bs_queue) must have been built up previous | |
4548 | * via bdrv_reopen_queue(). | |
4549 | * | |
4550 | * Reopens all BDS specified in the queue, with the appropriate | |
4551 | * flags. All devices are prepared for reopen, and failure of any | |
50d6a8a3 | 4552 | * device will cause all device changes to be abandoned, and intermediate |
e971aa12 JC |
4553 | * data cleaned up. |
4554 | * | |
4555 | * If all devices prepare successfully, then the changes are committed | |
4556 | * to all devices. | |
4557 | * | |
1a63a907 KW |
4558 | * All affected nodes must be drained between bdrv_reopen_queue() and |
4559 | * bdrv_reopen_multiple(). | |
6cf42ca2 KW |
4560 | * |
4561 | * To be called from the main thread, with all other AioContexts unlocked. | |
e971aa12 | 4562 | */ |
5019aece | 4563 | int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) |
e971aa12 JC |
4564 | { |
4565 | int ret = -1; | |
4566 | BlockReopenQueueEntry *bs_entry, *next; | |
6cf42ca2 | 4567 | AioContext *ctx; |
72373e40 | 4568 | Transaction *tran = tran_new(); |
72373e40 | 4569 | g_autoptr(GSList) refresh_list = NULL; |
e971aa12 | 4570 | |
6cf42ca2 | 4571 | assert(qemu_get_current_aio_context() == qemu_get_aio_context()); |
e971aa12 | 4572 | assert(bs_queue != NULL); |
da359909 | 4573 | GLOBAL_STATE_CODE(); |
e971aa12 | 4574 | |
a2aabf88 | 4575 | QTAILQ_FOREACH(bs_entry, bs_queue, entry) { |
6cf42ca2 KW |
4576 | ctx = bdrv_get_aio_context(bs_entry->state.bs); |
4577 | aio_context_acquire(ctx); | |
a2aabf88 | 4578 | ret = bdrv_flush(bs_entry->state.bs); |
6cf42ca2 | 4579 | aio_context_release(ctx); |
a2aabf88 VSO |
4580 | if (ret < 0) { |
4581 | error_setg_errno(errp, -ret, "Error flushing drive"); | |
e3fc91aa | 4582 | goto abort; |
a2aabf88 VSO |
4583 | } |
4584 | } | |
4585 | ||
859443b0 | 4586 | QTAILQ_FOREACH(bs_entry, bs_queue, entry) { |
1a63a907 | 4587 | assert(bs_entry->state.bs->quiesce_counter > 0); |
6cf42ca2 KW |
4588 | ctx = bdrv_get_aio_context(bs_entry->state.bs); |
4589 | aio_context_acquire(ctx); | |
72373e40 | 4590 | ret = bdrv_reopen_prepare(&bs_entry->state, bs_queue, tran, errp); |
6cf42ca2 | 4591 | aio_context_release(ctx); |
72373e40 VSO |
4592 | if (ret < 0) { |
4593 | goto abort; | |
e971aa12 JC |
4594 | } |
4595 | bs_entry->prepared = true; | |
4596 | } | |
4597 | ||
859443b0 | 4598 | QTAILQ_FOREACH(bs_entry, bs_queue, entry) { |
69b736e7 | 4599 | BDRVReopenState *state = &bs_entry->state; |
72373e40 | 4600 | |
fb0ff4d1 | 4601 | refresh_list = g_slist_prepend(refresh_list, state->bs); |
72373e40 | 4602 | if (state->old_backing_bs) { |
fb0ff4d1 | 4603 | refresh_list = g_slist_prepend(refresh_list, state->old_backing_bs); |
cb828c31 | 4604 | } |
ecd30d2d | 4605 | if (state->old_file_bs) { |
fb0ff4d1 | 4606 | refresh_list = g_slist_prepend(refresh_list, state->old_file_bs); |
ecd30d2d | 4607 | } |
72373e40 VSO |
4608 | } |
4609 | ||
4610 | /* | |
4611 | * Note that file-posix driver rely on permission update done during reopen | |
4612 | * (even if no permission changed), because it wants "new" permissions for | |
4613 | * reconfiguring the fd and that's why it does it in raw_check_perm(), not | |
4614 | * in raw_reopen_prepare() which is called with "old" permissions. | |
4615 | */ | |
3804e3cf | 4616 | bdrv_graph_rdlock_main_loop(); |
72373e40 | 4617 | ret = bdrv_list_refresh_perms(refresh_list, bs_queue, tran, errp); |
3804e3cf KW |
4618 | bdrv_graph_rdunlock_main_loop(); |
4619 | ||
72373e40 VSO |
4620 | if (ret < 0) { |
4621 | goto abort; | |
69b736e7 KW |
4622 | } |
4623 | ||
fcd6a4f4 VSO |
4624 | /* |
4625 | * If we reach this point, we have success and just need to apply the | |
4626 | * changes. | |
4627 | * | |
4628 | * Reverse order is used to comfort qcow2 driver: on commit it need to write | |
4629 | * IN_USE flag to the image, to mark bitmaps in the image as invalid. But | |
4630 | * children are usually goes after parents in reopen-queue, so go from last | |
4631 | * to first element. | |
e971aa12 | 4632 | */ |
fcd6a4f4 | 4633 | QTAILQ_FOREACH_REVERSE(bs_entry, bs_queue, entry) { |
6cf42ca2 KW |
4634 | ctx = bdrv_get_aio_context(bs_entry->state.bs); |
4635 | aio_context_acquire(ctx); | |
e971aa12 | 4636 | bdrv_reopen_commit(&bs_entry->state); |
6cf42ca2 | 4637 | aio_context_release(ctx); |
e971aa12 JC |
4638 | } |
4639 | ||
5661a00d | 4640 | bdrv_graph_wrlock(NULL); |
72373e40 | 4641 | tran_commit(tran); |
5661a00d | 4642 | bdrv_graph_wrunlock(); |
69b736e7 | 4643 | |
72373e40 VSO |
4644 | QTAILQ_FOREACH_REVERSE(bs_entry, bs_queue, entry) { |
4645 | BlockDriverState *bs = bs_entry->state.bs; | |
74ad9a3b | 4646 | |
72373e40 | 4647 | if (bs->drv->bdrv_reopen_commit_post) { |
6cf42ca2 KW |
4648 | ctx = bdrv_get_aio_context(bs); |
4649 | aio_context_acquire(ctx); | |
72373e40 | 4650 | bs->drv->bdrv_reopen_commit_post(&bs_entry->state); |
6cf42ca2 | 4651 | aio_context_release(ctx); |
69b736e7 KW |
4652 | } |
4653 | } | |
17e1e2be | 4654 | |
72373e40 VSO |
4655 | ret = 0; |
4656 | goto cleanup; | |
17e1e2be | 4657 | |
72373e40 | 4658 | abort: |
5661a00d | 4659 | bdrv_graph_wrlock(NULL); |
72373e40 | 4660 | tran_abort(tran); |
5661a00d | 4661 | bdrv_graph_wrunlock(); |
7d4ca9d2 | 4662 | |
72373e40 VSO |
4663 | QTAILQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) { |
4664 | if (bs_entry->prepared) { | |
6cf42ca2 KW |
4665 | ctx = bdrv_get_aio_context(bs_entry->state.bs); |
4666 | aio_context_acquire(ctx); | |
72373e40 | 4667 | bdrv_reopen_abort(&bs_entry->state); |
6cf42ca2 | 4668 | aio_context_release(ctx); |
17e1e2be PK |
4669 | } |
4670 | } | |
72373e40 | 4671 | |
e971aa12 | 4672 | cleanup: |
ab5b5228 | 4673 | bdrv_reopen_queue_free(bs_queue); |
40840e41 | 4674 | |
e971aa12 JC |
4675 | return ret; |
4676 | } | |
4677 | ||
6cf42ca2 KW |
4678 | int bdrv_reopen(BlockDriverState *bs, QDict *opts, bool keep_old_opts, |
4679 | Error **errp) | |
6e1000a8 | 4680 | { |
6cf42ca2 | 4681 | AioContext *ctx = bdrv_get_aio_context(bs); |
6e1000a8 | 4682 | BlockReopenQueue *queue; |
6cf42ca2 | 4683 | int ret; |
6e1000a8 | 4684 | |
f791bf7f EGE |
4685 | GLOBAL_STATE_CODE(); |
4686 | ||
2e117866 KW |
4687 | queue = bdrv_reopen_queue(NULL, bs, opts, keep_old_opts); |
4688 | ||
6cf42ca2 KW |
4689 | if (ctx != qemu_get_aio_context()) { |
4690 | aio_context_release(ctx); | |
4691 | } | |
5019aece | 4692 | ret = bdrv_reopen_multiple(queue, errp); |
6cf42ca2 KW |
4693 | |
4694 | if (ctx != qemu_get_aio_context()) { | |
4695 | aio_context_acquire(ctx); | |
4696 | } | |
6e1000a8 AG |
4697 | |
4698 | return ret; | |
4699 | } | |
4700 | ||
6cf42ca2 KW |
4701 | int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, |
4702 | Error **errp) | |
4703 | { | |
4704 | QDict *opts = qdict_new(); | |
4705 | ||
f791bf7f EGE |
4706 | GLOBAL_STATE_CODE(); |
4707 | ||
6cf42ca2 KW |
4708 | qdict_put_bool(opts, BDRV_OPT_READ_ONLY, read_only); |
4709 | ||
4710 | return bdrv_reopen(bs, opts, true, errp); | |
4711 | } | |
4712 | ||
cb828c31 AG |
4713 | /* |
4714 | * Take a BDRVReopenState and check if the value of 'backing' in the | |
4715 | * reopen_state->options QDict is valid or not. | |
4716 | * | |
4717 | * If 'backing' is missing from the QDict then return 0. | |
4718 | * | |
4719 | * If 'backing' contains the node name of the backing file of | |
4720 | * reopen_state->bs then return 0. | |
4721 | * | |
4722 | * If 'backing' contains a different node name (or is null) then check | |
4723 | * whether the current backing file can be replaced with the new one. | |
4724 | * If that's the case then reopen_state->replace_backing_bs is set to | |
4725 | * true and reopen_state->new_backing_bs contains a pointer to the new | |
4726 | * backing BlockDriverState (or NULL). | |
4727 | * | |
5661a00d KW |
4728 | * After calling this function, the transaction @tran may only be completed |
4729 | * while holding a writer lock for the graph. | |
4730 | * | |
cb828c31 | 4731 | * Return 0 on success, otherwise return < 0 and set @errp. |
4b408668 KW |
4732 | * |
4733 | * The caller must hold the AioContext lock of @reopen_state->bs. | |
4734 | * @reopen_state->bs can move to a different AioContext in this function. | |
4735 | * Callers must make sure that their AioContext locking is still correct after | |
4736 | * this. | |
cb828c31 | 4737 | */ |
ecd30d2d AG |
4738 | static int bdrv_reopen_parse_file_or_backing(BDRVReopenState *reopen_state, |
4739 | bool is_backing, Transaction *tran, | |
4740 | Error **errp) | |
cb828c31 AG |
4741 | { |
4742 | BlockDriverState *bs = reopen_state->bs; | |
ecd30d2d AG |
4743 | BlockDriverState *new_child_bs; |
4744 | BlockDriverState *old_child_bs = is_backing ? child_bs(bs->backing) : | |
4745 | child_bs(bs->file); | |
4746 | const char *child_name = is_backing ? "backing" : "file"; | |
cb828c31 AG |
4747 | QObject *value; |
4748 | const char *str; | |
4b408668 KW |
4749 | AioContext *ctx, *old_ctx; |
4750 | int ret; | |
cb828c31 | 4751 | |
bdb73476 EGE |
4752 | GLOBAL_STATE_CODE(); |
4753 | ||
ecd30d2d | 4754 | value = qdict_get(reopen_state->options, child_name); |
cb828c31 AG |
4755 | if (value == NULL) { |
4756 | return 0; | |
4757 | } | |
4758 | ||
4759 | switch (qobject_type(value)) { | |
4760 | case QTYPE_QNULL: | |
ecd30d2d AG |
4761 | assert(is_backing); /* The 'file' option does not allow a null value */ |
4762 | new_child_bs = NULL; | |
cb828c31 AG |
4763 | break; |
4764 | case QTYPE_QSTRING: | |
410f44f5 | 4765 | str = qstring_get_str(qobject_to(QString, value)); |
ecd30d2d AG |
4766 | new_child_bs = bdrv_lookup_bs(NULL, str, errp); |
4767 | if (new_child_bs == NULL) { | |
cb828c31 | 4768 | return -EINVAL; |
ecd30d2d AG |
4769 | } else if (bdrv_recurse_has_child(new_child_bs, bs)) { |
4770 | error_setg(errp, "Making '%s' a %s child of '%s' would create a " | |
4771 | "cycle", str, child_name, bs->node_name); | |
cb828c31 AG |
4772 | return -EINVAL; |
4773 | } | |
4774 | break; | |
4775 | default: | |
ecd30d2d AG |
4776 | /* |
4777 | * The options QDict has been flattened, so 'backing' and 'file' | |
4778 | * do not allow any other data type here. | |
4779 | */ | |
cb828c31 AG |
4780 | g_assert_not_reached(); |
4781 | } | |
4782 | ||
ecd30d2d AG |
4783 | if (old_child_bs == new_child_bs) { |
4784 | return 0; | |
4785 | } | |
4786 | ||
4787 | if (old_child_bs) { | |
4788 | if (bdrv_skip_implicit_filters(old_child_bs) == new_child_bs) { | |
cbfdb98c VSO |
4789 | return 0; |
4790 | } | |
4791 | ||
ecd30d2d AG |
4792 | if (old_child_bs->implicit) { |
4793 | error_setg(errp, "Cannot replace implicit %s child of %s", | |
4794 | child_name, bs->node_name); | |
cbfdb98c VSO |
4795 | return -EPERM; |
4796 | } | |
4797 | } | |
4798 | ||
ecd30d2d | 4799 | if (bs->drv->is_filter && !old_child_bs) { |
25f78d9e VSO |
4800 | /* |
4801 | * Filters always have a file or a backing child, so we are trying to | |
4802 | * change wrong child | |
4803 | */ | |
4804 | error_setg(errp, "'%s' is a %s filter node that does not support a " | |
ecd30d2d | 4805 | "%s child", bs->node_name, bs->drv->format_name, child_name); |
1d42f48c HR |
4806 | return -EINVAL; |
4807 | } | |
4808 | ||
ecd30d2d AG |
4809 | if (is_backing) { |
4810 | reopen_state->old_backing_bs = old_child_bs; | |
4811 | } else { | |
4812 | reopen_state->old_file_bs = old_child_bs; | |
4813 | } | |
4814 | ||
7d4ca9d2 KW |
4815 | if (old_child_bs) { |
4816 | bdrv_ref(old_child_bs); | |
4817 | bdrv_drained_begin(old_child_bs); | |
4818 | } | |
4819 | ||
4b408668 KW |
4820 | old_ctx = bdrv_get_aio_context(bs); |
4821 | ctx = bdrv_get_aio_context(new_child_bs); | |
4822 | if (old_ctx != ctx) { | |
4823 | aio_context_release(old_ctx); | |
4824 | aio_context_acquire(ctx); | |
4825 | } | |
4826 | ||
7d4ca9d2 KW |
4827 | bdrv_graph_wrlock(new_child_bs); |
4828 | ||
4b408668 KW |
4829 | ret = bdrv_set_file_or_backing_noperm(bs, new_child_bs, is_backing, |
4830 | tran, errp); | |
4831 | ||
7d4ca9d2 KW |
4832 | bdrv_graph_wrunlock(); |
4833 | ||
4b408668 KW |
4834 | if (old_ctx != ctx) { |
4835 | aio_context_release(ctx); | |
4836 | aio_context_acquire(old_ctx); | |
4837 | } | |
4838 | ||
7d4ca9d2 KW |
4839 | if (old_child_bs) { |
4840 | bdrv_drained_end(old_child_bs); | |
4841 | bdrv_unref(old_child_bs); | |
4842 | } | |
4843 | ||
4b408668 | 4844 | return ret; |
cb828c31 AG |
4845 | } |
4846 | ||
e971aa12 JC |
4847 | /* |
4848 | * Prepares a BlockDriverState for reopen. All changes are staged in the | |
4849 | * 'opaque' field of the BDRVReopenState, which is used and allocated by | |
4850 | * the block driver layer .bdrv_reopen_prepare() | |
4851 | * | |
4852 | * bs is the BlockDriverState to reopen | |
4853 | * flags are the new open flags | |
4854 | * queue is the reopen queue | |
4855 | * | |
4856 | * Returns 0 on success, non-zero on error. On error errp will be set | |
4857 | * as well. | |
4858 | * | |
4859 | * On failure, bdrv_reopen_abort() will be called to clean up any data. | |
4860 | * It is the responsibility of the caller to then call the abort() or | |
4861 | * commit() for any other BDS that have been left in a prepare() state | |
4862 | * | |
4b408668 | 4863 | * The caller must hold the AioContext lock of @reopen_state->bs. |
5661a00d KW |
4864 | * |
4865 | * After calling this function, the transaction @change_child_tran may only be | |
4866 | * completed while holding a writer lock for the graph. | |
e971aa12 | 4867 | */ |
53e96d1e | 4868 | static int bdrv_reopen_prepare(BDRVReopenState *reopen_state, |
72373e40 | 4869 | BlockReopenQueue *queue, |
ecd30d2d | 4870 | Transaction *change_child_tran, Error **errp) |
e971aa12 JC |
4871 | { |
4872 | int ret = -1; | |
e6d79c41 | 4873 | int old_flags; |
e971aa12 JC |
4874 | Error *local_err = NULL; |
4875 | BlockDriver *drv; | |
ccf9dc07 | 4876 | QemuOpts *opts; |
4c8350fe | 4877 | QDict *orig_reopen_opts; |
593b3071 | 4878 | char *discard = NULL; |
3d8ce171 | 4879 | bool read_only; |
9ad08c44 | 4880 | bool drv_prepared = false; |
e971aa12 JC |
4881 | |
4882 | assert(reopen_state != NULL); | |
4883 | assert(reopen_state->bs->drv != NULL); | |
da359909 | 4884 | GLOBAL_STATE_CODE(); |
e971aa12 JC |
4885 | drv = reopen_state->bs->drv; |
4886 | ||
4c8350fe AG |
4887 | /* This function and each driver's bdrv_reopen_prepare() remove |
4888 | * entries from reopen_state->options as they are processed, so | |
4889 | * we need to make a copy of the original QDict. */ | |
4890 | orig_reopen_opts = qdict_clone_shallow(reopen_state->options); | |
4891 | ||
ccf9dc07 KW |
4892 | /* Process generic block layer options */ |
4893 | opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort); | |
af175e85 | 4894 | if (!qemu_opts_absorb_qdict(opts, reopen_state->options, errp)) { |
ccf9dc07 KW |
4895 | ret = -EINVAL; |
4896 | goto error; | |
4897 | } | |
4898 | ||
e6d79c41 AG |
4899 | /* This was already called in bdrv_reopen_queue_child() so the flags |
4900 | * are up-to-date. This time we simply want to remove the options from | |
4901 | * QemuOpts in order to indicate that they have been processed. */ | |
4902 | old_flags = reopen_state->flags; | |
91a097e7 | 4903 | update_flags_from_options(&reopen_state->flags, opts); |
e6d79c41 | 4904 | assert(old_flags == reopen_state->flags); |
91a097e7 | 4905 | |
415bbca8 | 4906 | discard = qemu_opt_get_del(opts, BDRV_OPT_DISCARD); |
593b3071 AG |
4907 | if (discard != NULL) { |
4908 | if (bdrv_parse_discard_flags(discard, &reopen_state->flags) != 0) { | |
4909 | error_setg(errp, "Invalid discard option"); | |
4910 | ret = -EINVAL; | |
4911 | goto error; | |
4912 | } | |
4913 | } | |
4914 | ||
543770bd AG |
4915 | reopen_state->detect_zeroes = |
4916 | bdrv_parse_detect_zeroes(opts, reopen_state->flags, &local_err); | |
4917 | if (local_err) { | |
4918 | error_propagate(errp, local_err); | |
4919 | ret = -EINVAL; | |
4920 | goto error; | |
4921 | } | |
4922 | ||
57f9db9a AG |
4923 | /* All other options (including node-name and driver) must be unchanged. |
4924 | * Put them back into the QDict, so that they are checked at the end | |
4925 | * of this function. */ | |
4926 | qemu_opts_to_qdict(opts, reopen_state->options); | |
ccf9dc07 | 4927 | |
3d8ce171 JC |
4928 | /* If we are to stay read-only, do not allow permission change |
4929 | * to r/w. Attempting to set to r/w may fail if either BDRV_O_ALLOW_RDWR is | |
4930 | * not set, or if the BDS still has copy_on_read enabled */ | |
4931 | read_only = !(reopen_state->flags & BDRV_O_RDWR); | |
54a32bfe | 4932 | ret = bdrv_can_set_read_only(reopen_state->bs, read_only, true, &local_err); |
3d8ce171 JC |
4933 | if (local_err) { |
4934 | error_propagate(errp, local_err); | |
e971aa12 JC |
4935 | goto error; |
4936 | } | |
4937 | ||
e971aa12 | 4938 | if (drv->bdrv_reopen_prepare) { |
faf116b4 AG |
4939 | /* |
4940 | * If a driver-specific option is missing, it means that we | |
4941 | * should reset it to its default value. | |
4942 | * But not all options allow that, so we need to check it first. | |
4943 | */ | |
4944 | ret = bdrv_reset_options_allowed(reopen_state->bs, | |
4945 | reopen_state->options, errp); | |
4946 | if (ret) { | |
4947 | goto error; | |
4948 | } | |
4949 | ||
e971aa12 JC |
4950 | ret = drv->bdrv_reopen_prepare(reopen_state, queue, &local_err); |
4951 | if (ret) { | |
4952 | if (local_err != NULL) { | |
4953 | error_propagate(errp, local_err); | |
4954 | } else { | |
f30c66ba | 4955 | bdrv_refresh_filename(reopen_state->bs); |
d8b6895f LC |
4956 | error_setg(errp, "failed while preparing to reopen image '%s'", |
4957 | reopen_state->bs->filename); | |
e971aa12 JC |
4958 | } |
4959 | goto error; | |
4960 | } | |
4961 | } else { | |
4962 | /* It is currently mandatory to have a bdrv_reopen_prepare() | |
4963 | * handler for each supported drv. */ | |
81e5f78a AG |
4964 | error_setg(errp, "Block format '%s' used by node '%s' " |
4965 | "does not support reopening files", drv->format_name, | |
4966 | bdrv_get_device_or_node_name(reopen_state->bs)); | |
e971aa12 JC |
4967 | ret = -1; |
4968 | goto error; | |
4969 | } | |
4970 | ||
9ad08c44 HR |
4971 | drv_prepared = true; |
4972 | ||
bacd9b87 AG |
4973 | /* |
4974 | * We must provide the 'backing' option if the BDS has a backing | |
4975 | * file or if the image file has a backing file name as part of | |
4976 | * its metadata. Otherwise the 'backing' option can be omitted. | |
4977 | */ | |
4978 | if (drv->supports_backing && reopen_state->backing_missing && | |
1d42f48c | 4979 | (reopen_state->bs->backing || reopen_state->bs->backing_file[0])) { |
8546632e AG |
4980 | error_setg(errp, "backing is missing for '%s'", |
4981 | reopen_state->bs->node_name); | |
4982 | ret = -EINVAL; | |
4983 | goto error; | |
4984 | } | |
4985 | ||
cb828c31 AG |
4986 | /* |
4987 | * Allow changing the 'backing' option. The new value can be | |
4988 | * either a reference to an existing node (using its node name) | |
4989 | * or NULL to simply detach the current backing file. | |
4990 | */ | |
ecd30d2d AG |
4991 | ret = bdrv_reopen_parse_file_or_backing(reopen_state, true, |
4992 | change_child_tran, errp); | |
cb828c31 AG |
4993 | if (ret < 0) { |
4994 | goto error; | |
4995 | } | |
4996 | qdict_del(reopen_state->options, "backing"); | |
4997 | ||
ecd30d2d AG |
4998 | /* Allow changing the 'file' option. In this case NULL is not allowed */ |
4999 | ret = bdrv_reopen_parse_file_or_backing(reopen_state, false, | |
5000 | change_child_tran, errp); | |
5001 | if (ret < 0) { | |
5002 | goto error; | |
5003 | } | |
5004 | qdict_del(reopen_state->options, "file"); | |
5005 | ||
4d2cb092 KW |
5006 | /* Options that are not handled are only okay if they are unchanged |
5007 | * compared to the old state. It is expected that some options are only | |
5008 | * used for the initial open, but not reopen (e.g. filename) */ | |
5009 | if (qdict_size(reopen_state->options)) { | |
5010 | const QDictEntry *entry = qdict_first(reopen_state->options); | |
5011 | ||
5012 | do { | |
54fd1b0d HR |
5013 | QObject *new = entry->value; |
5014 | QObject *old = qdict_get(reopen_state->bs->options, entry->key); | |
5015 | ||
db905283 AG |
5016 | /* Allow child references (child_name=node_name) as long as they |
5017 | * point to the current child (i.e. everything stays the same). */ | |
5018 | if (qobject_type(new) == QTYPE_QSTRING) { | |
5019 | BdrvChild *child; | |
5020 | QLIST_FOREACH(child, &reopen_state->bs->children, next) { | |
5021 | if (!strcmp(child->name, entry->key)) { | |
5022 | break; | |
5023 | } | |
5024 | } | |
5025 | ||
5026 | if (child) { | |
410f44f5 MA |
5027 | if (!strcmp(child->bs->node_name, |
5028 | qstring_get_str(qobject_to(QString, new)))) { | |
db905283 AG |
5029 | continue; /* Found child with this name, skip option */ |
5030 | } | |
5031 | } | |
5032 | } | |
5033 | ||
129c7d1c | 5034 | /* |
54fd1b0d HR |
5035 | * TODO: When using -drive to specify blockdev options, all values |
5036 | * will be strings; however, when using -blockdev, blockdev-add or | |
5037 | * filenames using the json:{} pseudo-protocol, they will be | |
5038 | * correctly typed. | |
5039 | * In contrast, reopening options are (currently) always strings | |
5040 | * (because you can only specify them through qemu-io; all other | |
5041 | * callers do not specify any options). | |
5042 | * Therefore, when using anything other than -drive to create a BDS, | |
5043 | * this cannot detect non-string options as unchanged, because | |
5044 | * qobject_is_equal() always returns false for objects of different | |
5045 | * type. In the future, this should be remedied by correctly typing | |
5046 | * all options. For now, this is not too big of an issue because | |
5047 | * the user can simply omit options which cannot be changed anyway, | |
5048 | * so they will stay unchanged. | |
129c7d1c | 5049 | */ |
54fd1b0d | 5050 | if (!qobject_is_equal(new, old)) { |
4d2cb092 KW |
5051 | error_setg(errp, "Cannot change the option '%s'", entry->key); |
5052 | ret = -EINVAL; | |
5053 | goto error; | |
5054 | } | |
5055 | } while ((entry = qdict_next(reopen_state->options, entry))); | |
5056 | } | |
5057 | ||
e971aa12 JC |
5058 | ret = 0; |
5059 | ||
4c8350fe AG |
5060 | /* Restore the original reopen_state->options QDict */ |
5061 | qobject_unref(reopen_state->options); | |
5062 | reopen_state->options = qobject_ref(orig_reopen_opts); | |
5063 | ||
e971aa12 | 5064 | error: |
9ad08c44 HR |
5065 | if (ret < 0 && drv_prepared) { |
5066 | /* drv->bdrv_reopen_prepare() has succeeded, so we need to | |
5067 | * call drv->bdrv_reopen_abort() before signaling an error | |
5068 | * (bdrv_reopen_multiple() will not call bdrv_reopen_abort() | |
5069 | * when the respective bdrv_reopen_prepare() has failed) */ | |
5070 | if (drv->bdrv_reopen_abort) { | |
5071 | drv->bdrv_reopen_abort(reopen_state); | |
5072 | } | |
5073 | } | |
ccf9dc07 | 5074 | qemu_opts_del(opts); |
4c8350fe | 5075 | qobject_unref(orig_reopen_opts); |
593b3071 | 5076 | g_free(discard); |
e971aa12 JC |
5077 | return ret; |
5078 | } | |
5079 | ||
5080 | /* | |
5081 | * Takes the staged changes for the reopen from bdrv_reopen_prepare(), and | |
5082 | * makes them final by swapping the staging BlockDriverState contents into | |
5083 | * the active BlockDriverState contents. | |
5084 | */ | |
53e96d1e | 5085 | static void bdrv_reopen_commit(BDRVReopenState *reopen_state) |
e971aa12 JC |
5086 | { |
5087 | BlockDriver *drv; | |
50bf65ba | 5088 | BlockDriverState *bs; |
50196d7a | 5089 | BdrvChild *child; |
e971aa12 JC |
5090 | |
5091 | assert(reopen_state != NULL); | |
50bf65ba VSO |
5092 | bs = reopen_state->bs; |
5093 | drv = bs->drv; | |
e971aa12 | 5094 | assert(drv != NULL); |
da359909 | 5095 | GLOBAL_STATE_CODE(); |
e971aa12 JC |
5096 | |
5097 | /* If there are any driver level actions to take */ | |
5098 | if (drv->bdrv_reopen_commit) { | |
5099 | drv->bdrv_reopen_commit(reopen_state); | |
5100 | } | |
5101 | ||
5102 | /* set BDS specific flags now */ | |
cb3e7f08 | 5103 | qobject_unref(bs->explicit_options); |
4c8350fe | 5104 | qobject_unref(bs->options); |
ab5b5228 AG |
5105 | qobject_ref(reopen_state->explicit_options); |
5106 | qobject_ref(reopen_state->options); | |
145f598e | 5107 | |
50bf65ba | 5108 | bs->explicit_options = reopen_state->explicit_options; |
4c8350fe | 5109 | bs->options = reopen_state->options; |
50bf65ba | 5110 | bs->open_flags = reopen_state->flags; |
543770bd | 5111 | bs->detect_zeroes = reopen_state->detect_zeroes; |
355ef4ac | 5112 | |
50196d7a AG |
5113 | /* Remove child references from bs->options and bs->explicit_options. |
5114 | * Child options were already removed in bdrv_reopen_queue_child() */ | |
5115 | QLIST_FOREACH(child, &bs->children, next) { | |
5116 | qdict_del(bs->explicit_options, child->name); | |
5117 | qdict_del(bs->options, child->name); | |
5118 | } | |
3d0e8743 VSO |
5119 | /* backing is probably removed, so it's not handled by previous loop */ |
5120 | qdict_del(bs->explicit_options, "backing"); | |
5121 | qdict_del(bs->options, "backing"); | |
5122 | ||
e19b157f | 5123 | bdrv_graph_rdlock_main_loop(); |
1e4c797c | 5124 | bdrv_refresh_limits(bs, NULL, NULL); |
e19b157f | 5125 | bdrv_graph_rdunlock_main_loop(); |
439cc330 | 5126 | bdrv_refresh_total_sectors(bs, bs->total_sectors); |
e971aa12 JC |
5127 | } |
5128 | ||
5129 | /* | |
5130 | * Abort the reopen, and delete and free the staged changes in | |
5131 | * reopen_state | |
5132 | */ | |
53e96d1e | 5133 | static void bdrv_reopen_abort(BDRVReopenState *reopen_state) |
e971aa12 JC |
5134 | { |
5135 | BlockDriver *drv; | |
5136 | ||
5137 | assert(reopen_state != NULL); | |
5138 | drv = reopen_state->bs->drv; | |
5139 | assert(drv != NULL); | |
da359909 | 5140 | GLOBAL_STATE_CODE(); |
e971aa12 JC |
5141 | |
5142 | if (drv->bdrv_reopen_abort) { | |
5143 | drv->bdrv_reopen_abort(reopen_state); | |
5144 | } | |
5145 | } | |
5146 | ||
5147 | ||
64dff520 | 5148 | static void bdrv_close(BlockDriverState *bs) |
fc01f7e7 | 5149 | { |
33384421 | 5150 | BdrvAioNotifier *ban, *ban_next; |
50a3efb0 | 5151 | BdrvChild *child, *next; |
33384421 | 5152 | |
f791bf7f | 5153 | GLOBAL_STATE_CODE(); |
30f55fb8 | 5154 | assert(!bs->refcnt); |
99b7e775 | 5155 | |
fc27291d | 5156 | bdrv_drained_begin(bs); /* complete I/O */ |
58fda173 | 5157 | bdrv_flush(bs); |
53ec73e2 | 5158 | bdrv_drain(bs); /* in case flush left pending I/O */ |
fc27291d | 5159 | |
3cbc002c | 5160 | if (bs->drv) { |
3c005293 | 5161 | if (bs->drv->bdrv_close) { |
7b99a266 | 5162 | /* Must unfreeze all children, so bdrv_unref_child() works */ |
3c005293 VSO |
5163 | bs->drv->bdrv_close(bs); |
5164 | } | |
9a4f4c31 | 5165 | bs->drv = NULL; |
50a3efb0 | 5166 | } |
9a7dedbc | 5167 | |
32a8aba3 | 5168 | bdrv_graph_wrlock(NULL); |
50a3efb0 | 5169 | QLIST_FOREACH_SAFE(child, &bs->children, next, next) { |
dd4118c7 | 5170 | bdrv_unref_child(bs, child); |
b338082b | 5171 | } |
32a8aba3 | 5172 | bdrv_graph_wrunlock(); |
98f90dba | 5173 | |
5bb04747 VSO |
5174 | assert(!bs->backing); |
5175 | assert(!bs->file); | |
50a3efb0 AG |
5176 | g_free(bs->opaque); |
5177 | bs->opaque = NULL; | |
d73415a3 | 5178 | qatomic_set(&bs->copy_on_read, 0); |
50a3efb0 AG |
5179 | bs->backing_file[0] = '\0'; |
5180 | bs->backing_format[0] = '\0'; | |
5181 | bs->total_sectors = 0; | |
5182 | bs->encrypted = false; | |
5183 | bs->sg = false; | |
cb3e7f08 MAL |
5184 | qobject_unref(bs->options); |
5185 | qobject_unref(bs->explicit_options); | |
50a3efb0 AG |
5186 | bs->options = NULL; |
5187 | bs->explicit_options = NULL; | |
cb3e7f08 | 5188 | qobject_unref(bs->full_open_options); |
50a3efb0 | 5189 | bs->full_open_options = NULL; |
0bc329fb HR |
5190 | g_free(bs->block_status_cache); |
5191 | bs->block_status_cache = NULL; | |
50a3efb0 | 5192 | |
cca43ae1 VSO |
5193 | bdrv_release_named_dirty_bitmaps(bs); |
5194 | assert(QLIST_EMPTY(&bs->dirty_bitmaps)); | |
5195 | ||
33384421 HR |
5196 | QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_next) { |
5197 | g_free(ban); | |
5198 | } | |
5199 | QLIST_INIT(&bs->aio_notifiers); | |
fc27291d | 5200 | bdrv_drained_end(bs); |
1a6d3bd2 GK |
5201 | |
5202 | /* | |
5203 | * If we're still inside some bdrv_drain_all_begin()/end() sections, end | |
5204 | * them now since this BDS won't exist anymore when bdrv_drain_all_end() | |
5205 | * gets called. | |
5206 | */ | |
5207 | if (bs->quiesce_counter) { | |
5208 | bdrv_drain_all_end_quiesce(bs); | |
5209 | } | |
b338082b FB |
5210 | } |
5211 | ||
2bc93fed MK |
5212 | void bdrv_close_all(void) |
5213 | { | |
f791bf7f | 5214 | GLOBAL_STATE_CODE(); |
880eeec6 | 5215 | assert(job_next(NULL) == NULL); |
ca9bd24c HR |
5216 | |
5217 | /* Drop references from requests still in flight, such as canceled block | |
5218 | * jobs whose AIO context has not been polled yet */ | |
5219 | bdrv_drain_all(); | |
2bc93fed | 5220 | |
ca9bd24c HR |
5221 | blk_remove_all_bs(); |
5222 | blockdev_close_all_bdrv_states(); | |
ed78cda3 | 5223 | |
a1a2af07 | 5224 | assert(QTAILQ_EMPTY(&all_bdrv_states)); |
2bc93fed MK |
5225 | } |
5226 | ||
2f64e1fc | 5227 | static bool GRAPH_RDLOCK should_update_child(BdrvChild *c, BlockDriverState *to) |
d0ac0380 | 5228 | { |
2f30b7c3 VSO |
5229 | GQueue *queue; |
5230 | GHashTable *found; | |
5231 | bool ret; | |
d0ac0380 | 5232 | |
bd86fb99 | 5233 | if (c->klass->stay_at_node) { |
d0ac0380 KW |
5234 | return false; |
5235 | } | |
5236 | ||
ec9f10fe HR |
5237 | /* If the child @c belongs to the BDS @to, replacing the current |
5238 | * c->bs by @to would mean to create a loop. | |
5239 | * | |
5240 | * Such a case occurs when appending a BDS to a backing chain. | |
5241 | * For instance, imagine the following chain: | |
5242 | * | |
5243 | * guest device -> node A -> further backing chain... | |
5244 | * | |
5245 | * Now we create a new BDS B which we want to put on top of this | |
5246 | * chain, so we first attach A as its backing node: | |
5247 | * | |
5248 | * node B | |
5249 | * | | |
5250 | * v | |
5251 | * guest device -> node A -> further backing chain... | |
5252 | * | |
5253 | * Finally we want to replace A by B. When doing that, we want to | |
5254 | * replace all pointers to A by pointers to B -- except for the | |
5255 | * pointer from B because (1) that would create a loop, and (2) | |
5256 | * that pointer should simply stay intact: | |
5257 | * | |
5258 | * guest device -> node B | |
5259 | * | | |
5260 | * v | |
5261 | * node A -> further backing chain... | |
5262 | * | |
5263 | * In general, when replacing a node A (c->bs) by a node B (@to), | |
5264 | * if A is a child of B, that means we cannot replace A by B there | |
5265 | * because that would create a loop. Silently detaching A from B | |
5266 | * is also not really an option. So overall just leaving A in | |
2f30b7c3 VSO |
5267 | * place there is the most sensible choice. |
5268 | * | |
5269 | * We would also create a loop in any cases where @c is only | |
5270 | * indirectly referenced by @to. Prevent this by returning false | |
5271 | * if @c is found (by breadth-first search) anywhere in the whole | |
5272 | * subtree of @to. | |
5273 | */ | |
5274 | ||
5275 | ret = true; | |
5276 | found = g_hash_table_new(NULL, NULL); | |
5277 | g_hash_table_add(found, to); | |
5278 | queue = g_queue_new(); | |
5279 | g_queue_push_tail(queue, to); | |
5280 | ||
5281 | while (!g_queue_is_empty(queue)) { | |
5282 | BlockDriverState *v = g_queue_pop_head(queue); | |
5283 | BdrvChild *c2; | |
5284 | ||
5285 | QLIST_FOREACH(c2, &v->children, next) { | |
5286 | if (c2 == c) { | |
5287 | ret = false; | |
5288 | break; | |
5289 | } | |
5290 | ||
5291 | if (g_hash_table_contains(found, c2->bs)) { | |
5292 | continue; | |
5293 | } | |
5294 | ||
5295 | g_queue_push_tail(queue, c2->bs); | |
5296 | g_hash_table_add(found, c2->bs); | |
d0ac0380 KW |
5297 | } |
5298 | } | |
5299 | ||
2f30b7c3 VSO |
5300 | g_queue_free(queue); |
5301 | g_hash_table_destroy(found); | |
5302 | ||
5303 | return ret; | |
d0ac0380 KW |
5304 | } |
5305 | ||
57f08941 | 5306 | static void bdrv_remove_child_commit(void *opaque) |
46541ee5 | 5307 | { |
bdb73476 | 5308 | GLOBAL_STATE_CODE(); |
5bb04747 | 5309 | bdrv_child_free(opaque); |
82b54cf5 HR |
5310 | } |
5311 | ||
57f08941 VSO |
5312 | static TransactionActionDrv bdrv_remove_child_drv = { |
5313 | .commit = bdrv_remove_child_commit, | |
46541ee5 VSO |
5314 | }; |
5315 | ||
2f64e1fc KW |
5316 | /* |
5317 | * Function doesn't update permissions, caller is responsible for this. | |
5318 | * | |
5319 | * @child->bs (if non-NULL) must be drained. | |
5661a00d KW |
5320 | * |
5321 | * After calling this function, the transaction @tran may only be completed | |
5322 | * while holding a writer lock for the graph. | |
2f64e1fc KW |
5323 | */ |
5324 | static void GRAPH_WRLOCK bdrv_remove_child(BdrvChild *child, Transaction *tran) | |
46541ee5 | 5325 | { |
46541ee5 VSO |
5326 | if (!child) { |
5327 | return; | |
5328 | } | |
5329 | ||
5330 | if (child->bs) { | |
2f64e1fc | 5331 | assert(child->quiesced_parent); |
a2c37a30 | 5332 | bdrv_replace_child_tran(child, NULL, tran); |
46541ee5 VSO |
5333 | } |
5334 | ||
57f08941 | 5335 | tran_add(tran, &bdrv_remove_child_drv, child); |
46541ee5 VSO |
5336 | } |
5337 | ||
2f64e1fc KW |
5338 | /* |
5339 | * Both @from and @to (if non-NULL) must be drained. @to must be kept drained | |
5340 | * until the transaction is completed. | |
5661a00d KW |
5341 | * |
5342 | * After calling this function, the transaction @tran may only be completed | |
5343 | * while holding a writer lock for the graph. | |
2f64e1fc KW |
5344 | */ |
5345 | static int GRAPH_WRLOCK | |
5346 | bdrv_replace_node_noperm(BlockDriverState *from, | |
5347 | BlockDriverState *to, | |
5348 | bool auto_skip, Transaction *tran, | |
5349 | Error **errp) | |
117caba9 VSO |
5350 | { |
5351 | BdrvChild *c, *next; | |
5352 | ||
bdb73476 | 5353 | GLOBAL_STATE_CODE(); |
82b54cf5 | 5354 | |
2f64e1fc KW |
5355 | assert(from->quiesce_counter); |
5356 | assert(to->quiesce_counter); | |
23987471 | 5357 | |
117caba9 VSO |
5358 | QLIST_FOREACH_SAFE(c, &from->parents, next_parent, next) { |
5359 | assert(c->bs == from); | |
5360 | if (!should_update_child(c, to)) { | |
5361 | if (auto_skip) { | |
5362 | continue; | |
5363 | } | |
5364 | error_setg(errp, "Should not change '%s' link to '%s'", | |
5365 | c->name, from->node_name); | |
5366 | return -EINVAL; | |
5367 | } | |
5368 | if (c->frozen) { | |
5369 | error_setg(errp, "Cannot change '%s' link to '%s'", | |
5370 | c->name, from->node_name); | |
5371 | return -EPERM; | |
5372 | } | |
0f0b1e29 | 5373 | bdrv_replace_child_tran(c, to, tran); |
117caba9 VSO |
5374 | } |
5375 | ||
5376 | return 0; | |
5377 | } | |
5378 | ||
313274bb VSO |
5379 | /* |
5380 | * With auto_skip=true bdrv_replace_node_common skips updating from parents | |
5381 | * if it creates a parent-child relation loop or if parent is block-job. | |
5382 | * | |
5383 | * With auto_skip=false the error is returned if from has a parent which should | |
5384 | * not be updated. | |
3108a15c VSO |
5385 | * |
5386 | * With @detach_subchain=true @to must be in a backing chain of @from. In this | |
5387 | * case backing link of the cow-parent of @to is removed. | |
313274bb | 5388 | */ |
a1e708fc VSO |
5389 | static int bdrv_replace_node_common(BlockDriverState *from, |
5390 | BlockDriverState *to, | |
3108a15c VSO |
5391 | bool auto_skip, bool detach_subchain, |
5392 | Error **errp) | |
dd62f1ca | 5393 | { |
3bb0e298 | 5394 | Transaction *tran = tran_new(); |
3bb0e298 | 5395 | g_autoptr(GSList) refresh_list = NULL; |
2d369d6e | 5396 | BlockDriverState *to_cow_parent = NULL; |
234ac1a9 KW |
5397 | int ret; |
5398 | ||
bdb73476 | 5399 | GLOBAL_STATE_CODE(); |
82b54cf5 | 5400 | |
3108a15c VSO |
5401 | if (detach_subchain) { |
5402 | assert(bdrv_chain_contains(from, to)); | |
5403 | assert(from != to); | |
5404 | for (to_cow_parent = from; | |
5405 | bdrv_filter_or_cow_bs(to_cow_parent) != to; | |
5406 | to_cow_parent = bdrv_filter_or_cow_bs(to_cow_parent)) | |
5407 | { | |
5408 | ; | |
5409 | } | |
5410 | } | |
5411 | ||
234ac1a9 KW |
5412 | /* Make sure that @from doesn't go away until we have successfully attached |
5413 | * all of its parents to @to. */ | |
5414 | bdrv_ref(from); | |
dd62f1ca | 5415 | |
f871abd6 | 5416 | assert(qemu_get_current_aio_context() == qemu_get_aio_context()); |
30dd65f3 | 5417 | assert(bdrv_get_aio_context(from) == bdrv_get_aio_context(to)); |
f871abd6 | 5418 | bdrv_drained_begin(from); |
2f64e1fc KW |
5419 | bdrv_drained_begin(to); |
5420 | ||
5421 | bdrv_graph_wrlock(to); | |
f871abd6 | 5422 | |
3bb0e298 VSO |
5423 | /* |
5424 | * Do the replacement without permission update. | |
5425 | * Replacement may influence the permissions, we should calculate new | |
5426 | * permissions based on new graph. If we fail, we'll roll-back the | |
5427 | * replacement. | |
5428 | */ | |
117caba9 VSO |
5429 | ret = bdrv_replace_node_noperm(from, to, auto_skip, tran, errp); |
5430 | if (ret < 0) { | |
5431 | goto out; | |
234ac1a9 KW |
5432 | } |
5433 | ||
3108a15c | 5434 | if (detach_subchain) { |
2f64e1fc | 5435 | /* to_cow_parent is already drained because from is drained */ |
f38eaec4 | 5436 | bdrv_remove_child(bdrv_filter_or_cow_child(to_cow_parent), tran); |
3108a15c VSO |
5437 | } |
5438 | ||
fb0ff4d1 VSO |
5439 | refresh_list = g_slist_prepend(refresh_list, to); |
5440 | refresh_list = g_slist_prepend(refresh_list, from); | |
9bd910e2 | 5441 | |
3bb0e298 VSO |
5442 | ret = bdrv_list_refresh_perms(refresh_list, NULL, tran, errp); |
5443 | if (ret < 0) { | |
5444 | goto out; | |
dd62f1ca | 5445 | } |
234ac1a9 | 5446 | |
a1e708fc VSO |
5447 | ret = 0; |
5448 | ||
234ac1a9 | 5449 | out: |
3bb0e298 | 5450 | tran_finalize(tran, ret); |
5661a00d | 5451 | bdrv_graph_wrunlock(); |
3bb0e298 | 5452 | |
2f64e1fc | 5453 | bdrv_drained_end(to); |
f871abd6 | 5454 | bdrv_drained_end(from); |
234ac1a9 | 5455 | bdrv_unref(from); |
a1e708fc VSO |
5456 | |
5457 | return ret; | |
dd62f1ca KW |
5458 | } |
5459 | ||
a1e708fc VSO |
5460 | int bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, |
5461 | Error **errp) | |
313274bb | 5462 | { |
f791bf7f EGE |
5463 | GLOBAL_STATE_CODE(); |
5464 | ||
3108a15c VSO |
5465 | return bdrv_replace_node_common(from, to, true, false, errp); |
5466 | } | |
5467 | ||
5468 | int bdrv_drop_filter(BlockDriverState *bs, Error **errp) | |
5469 | { | |
f791bf7f EGE |
5470 | GLOBAL_STATE_CODE(); |
5471 | ||
3108a15c VSO |
5472 | return bdrv_replace_node_common(bs, bdrv_filter_or_cow_bs(bs), true, true, |
5473 | errp); | |
313274bb VSO |
5474 | } |
5475 | ||
4ddc07ca PB |
5476 | /* |
5477 | * Add new bs contents at the top of an image chain while the chain is | |
5478 | * live, while keeping required fields on the top layer. | |
5479 | * | |
5480 | * This will modify the BlockDriverState fields, and swap contents | |
5481 | * between bs_new and bs_top. Both bs_new and bs_top are modified. | |
5482 | * | |
2272edcf VSO |
5483 | * bs_new must not be attached to a BlockBackend and must not have backing |
5484 | * child. | |
4ddc07ca PB |
5485 | * |
5486 | * This function does not create any image files. | |
60d90bf4 SG |
5487 | * |
5488 | * The caller must hold the AioContext lock for @bs_top. | |
4ddc07ca | 5489 | */ |
a1e708fc VSO |
5490 | int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, |
5491 | Error **errp) | |
4ddc07ca | 5492 | { |
2272edcf | 5493 | int ret; |
5bb04747 | 5494 | BdrvChild *child; |
2272edcf | 5495 | Transaction *tran = tran_new(); |
60d90bf4 | 5496 | AioContext *old_context, *new_context = NULL; |
2272edcf | 5497 | |
f791bf7f EGE |
5498 | GLOBAL_STATE_CODE(); |
5499 | ||
2272edcf VSO |
5500 | assert(!bs_new->backing); |
5501 | ||
60d90bf4 | 5502 | old_context = bdrv_get_aio_context(bs_top); |
7d4ca9d2 KW |
5503 | bdrv_drained_begin(bs_top); |
5504 | ||
5505 | /* | |
5506 | * bdrv_drained_begin() requires that only the AioContext of the drained | |
5507 | * node is locked, and at this point it can still differ from the AioContext | |
5508 | * of bs_top. | |
5509 | */ | |
5510 | new_context = bdrv_get_aio_context(bs_new); | |
5511 | aio_context_release(old_context); | |
5512 | aio_context_acquire(new_context); | |
5513 | bdrv_drained_begin(bs_new); | |
5514 | aio_context_release(new_context); | |
5515 | aio_context_acquire(old_context); | |
5516 | new_context = NULL; | |
5517 | ||
5518 | bdrv_graph_wrlock(bs_top); | |
60d90bf4 | 5519 | |
5bb04747 VSO |
5520 | child = bdrv_attach_child_noperm(bs_new, bs_top, "backing", |
5521 | &child_of_bds, bdrv_backing_role(bs_new), | |
5522 | tran, errp); | |
5523 | if (!child) { | |
5524 | ret = -EINVAL; | |
2272edcf | 5525 | goto out; |
b2c2832c | 5526 | } |
dd62f1ca | 5527 | |
60d90bf4 | 5528 | /* |
7d4ca9d2 KW |
5529 | * bdrv_attach_child_noperm could change the AioContext of bs_top and |
5530 | * bs_new, but at least they are in the same AioContext now. This is the | |
5531 | * AioContext that we need to lock for the rest of the function. | |
60d90bf4 SG |
5532 | */ |
5533 | new_context = bdrv_get_aio_context(bs_top); | |
5534 | ||
5535 | if (old_context != new_context) { | |
5536 | aio_context_release(old_context); | |
5537 | aio_context_acquire(new_context); | |
5538 | } | |
5539 | ||
2272edcf | 5540 | ret = bdrv_replace_node_noperm(bs_top, bs_new, true, tran, errp); |
a1e708fc | 5541 | if (ret < 0) { |
2272edcf | 5542 | goto out; |
234ac1a9 | 5543 | } |
4ddc07ca | 5544 | |
f1316edb | 5545 | ret = bdrv_refresh_perms(bs_new, tran, errp); |
2272edcf VSO |
5546 | out: |
5547 | tran_finalize(tran, ret); | |
5548 | ||
1e4c797c | 5549 | bdrv_refresh_limits(bs_top, NULL, NULL); |
5661a00d | 5550 | bdrv_graph_wrunlock(); |
2272edcf | 5551 | |
7d4ca9d2 KW |
5552 | bdrv_drained_end(bs_top); |
5553 | bdrv_drained_end(bs_new); | |
2f64e1fc | 5554 | |
60d90bf4 SG |
5555 | if (new_context && old_context != new_context) { |
5556 | aio_context_release(new_context); | |
5557 | aio_context_acquire(old_context); | |
5558 | } | |
5559 | ||
2272edcf | 5560 | return ret; |
8802d1fd JC |
5561 | } |
5562 | ||
bd8f4c42 VSO |
5563 | /* Not for empty child */ |
5564 | int bdrv_replace_child_bs(BdrvChild *child, BlockDriverState *new_bs, | |
5565 | Error **errp) | |
5566 | { | |
5567 | int ret; | |
5568 | Transaction *tran = tran_new(); | |
bd8f4c42 VSO |
5569 | g_autoptr(GSList) refresh_list = NULL; |
5570 | BlockDriverState *old_bs = child->bs; | |
5571 | ||
f791bf7f EGE |
5572 | GLOBAL_STATE_CODE(); |
5573 | ||
bd8f4c42 VSO |
5574 | bdrv_ref(old_bs); |
5575 | bdrv_drained_begin(old_bs); | |
5576 | bdrv_drained_begin(new_bs); | |
2f64e1fc | 5577 | bdrv_graph_wrlock(new_bs); |
bd8f4c42 | 5578 | |
0f0b1e29 | 5579 | bdrv_replace_child_tran(child, new_bs, tran); |
bd8f4c42 | 5580 | |
fb0ff4d1 VSO |
5581 | refresh_list = g_slist_prepend(refresh_list, old_bs); |
5582 | refresh_list = g_slist_prepend(refresh_list, new_bs); | |
bd8f4c42 VSO |
5583 | |
5584 | ret = bdrv_list_refresh_perms(refresh_list, NULL, tran, errp); | |
5585 | ||
5586 | tran_finalize(tran, ret); | |
5587 | ||
5661a00d | 5588 | bdrv_graph_wrunlock(); |
bd8f4c42 VSO |
5589 | bdrv_drained_end(old_bs); |
5590 | bdrv_drained_end(new_bs); | |
5591 | bdrv_unref(old_bs); | |
5592 | ||
5593 | return ret; | |
5594 | } | |
5595 | ||
4f6fd349 | 5596 | static void bdrv_delete(BlockDriverState *bs) |
b338082b | 5597 | { |
3718d8ab | 5598 | assert(bdrv_op_blocker_is_empty(bs)); |
4f6fd349 | 5599 | assert(!bs->refcnt); |
f791bf7f | 5600 | GLOBAL_STATE_CODE(); |
18846dee | 5601 | |
1b7bdbc1 | 5602 | /* remove from list, if necessary */ |
63eaaae0 KW |
5603 | if (bs->node_name[0] != '\0') { |
5604 | QTAILQ_REMOVE(&graph_bdrv_states, bs, node_list); | |
5605 | } | |
2c1d04e0 HR |
5606 | QTAILQ_REMOVE(&all_bdrv_states, bs, bs_list); |
5607 | ||
30c321f9 AK |
5608 | bdrv_close(bs); |
5609 | ||
fa9185fc SH |
5610 | qemu_mutex_destroy(&bs->reqs_lock); |
5611 | ||
7267c094 | 5612 | g_free(bs); |
fc01f7e7 FB |
5613 | } |
5614 | ||
96796fae VSO |
5615 | |
5616 | /* | |
5617 | * Replace @bs by newly created block node. | |
5618 | * | |
5619 | * @options is a QDict of options to pass to the block drivers, or NULL for an | |
5620 | * empty set of options. The reference to the QDict belongs to the block layer | |
5621 | * after the call (even on failure), so if the caller intends to reuse the | |
5622 | * dictionary, it needs to use qobject_ref() before calling bdrv_open. | |
8823407c KW |
5623 | * |
5624 | * The caller holds the AioContext lock for @bs. It must make sure that @bs | |
5625 | * stays in the same AioContext, i.e. @options must not refer to nodes in a | |
5626 | * different AioContext. | |
96796fae VSO |
5627 | */ |
5628 | BlockDriverState *bdrv_insert_node(BlockDriverState *bs, QDict *options, | |
8872ef78 AS |
5629 | int flags, Error **errp) |
5630 | { | |
f053b7e8 VSO |
5631 | ERRP_GUARD(); |
5632 | int ret; | |
8823407c | 5633 | AioContext *ctx = bdrv_get_aio_context(bs); |
b11c8739 VSO |
5634 | BlockDriverState *new_node_bs = NULL; |
5635 | const char *drvname, *node_name; | |
5636 | BlockDriver *drv; | |
5637 | ||
5638 | drvname = qdict_get_try_str(options, "driver"); | |
5639 | if (!drvname) { | |
5640 | error_setg(errp, "driver is not specified"); | |
5641 | goto fail; | |
5642 | } | |
5643 | ||
5644 | drv = bdrv_find_format(drvname); | |
5645 | if (!drv) { | |
5646 | error_setg(errp, "Unknown driver: '%s'", drvname); | |
5647 | goto fail; | |
5648 | } | |
8872ef78 | 5649 | |
b11c8739 VSO |
5650 | node_name = qdict_get_try_str(options, "node-name"); |
5651 | ||
f791bf7f EGE |
5652 | GLOBAL_STATE_CODE(); |
5653 | ||
8823407c KW |
5654 | aio_context_release(ctx); |
5655 | aio_context_acquire(qemu_get_aio_context()); | |
b11c8739 VSO |
5656 | new_node_bs = bdrv_new_open_driver_opts(drv, node_name, options, flags, |
5657 | errp); | |
8823407c KW |
5658 | aio_context_release(qemu_get_aio_context()); |
5659 | aio_context_acquire(ctx); | |
5660 | assert(bdrv_get_aio_context(bs) == ctx); | |
5661 | ||
b11c8739 VSO |
5662 | options = NULL; /* bdrv_new_open_driver() eats options */ |
5663 | if (!new_node_bs) { | |
8872ef78 | 5664 | error_prepend(errp, "Could not create node: "); |
b11c8739 | 5665 | goto fail; |
8872ef78 AS |
5666 | } |
5667 | ||
5668 | bdrv_drained_begin(bs); | |
f053b7e8 | 5669 | ret = bdrv_replace_node(bs, new_node_bs, errp); |
8872ef78 AS |
5670 | bdrv_drained_end(bs); |
5671 | ||
f053b7e8 VSO |
5672 | if (ret < 0) { |
5673 | error_prepend(errp, "Could not replace node: "); | |
b11c8739 | 5674 | goto fail; |
8872ef78 AS |
5675 | } |
5676 | ||
5677 | return new_node_bs; | |
b11c8739 VSO |
5678 | |
5679 | fail: | |
5680 | qobject_unref(options); | |
5681 | bdrv_unref(new_node_bs); | |
5682 | return NULL; | |
8872ef78 AS |
5683 | } |
5684 | ||
e97fc193 AL |
5685 | /* |
5686 | * Run consistency checks on an image | |
5687 | * | |
e076f338 | 5688 | * Returns 0 if the check could be completed (it doesn't mean that the image is |
a1c7273b | 5689 | * free of errors) or -errno when an internal error occurred. The results of the |
e076f338 | 5690 | * check are stored in res. |
e97fc193 | 5691 | */ |
21c2283e VSO |
5692 | int coroutine_fn bdrv_co_check(BlockDriverState *bs, |
5693 | BdrvCheckResult *res, BdrvCheckMode fix) | |
e97fc193 | 5694 | { |
1581a70d | 5695 | IO_CODE(); |
1b3ff9fe | 5696 | assert_bdrv_graph_readable(); |
908bcd54 HR |
5697 | if (bs->drv == NULL) { |
5698 | return -ENOMEDIUM; | |
5699 | } | |
2fd61638 | 5700 | if (bs->drv->bdrv_co_check == NULL) { |
e97fc193 AL |
5701 | return -ENOTSUP; |
5702 | } | |
5703 | ||
e076f338 | 5704 | memset(res, 0, sizeof(*res)); |
2fd61638 PB |
5705 | return bs->drv->bdrv_co_check(bs, res, fix); |
5706 | } | |
5707 | ||
756e6736 KW |
5708 | /* |
5709 | * Return values: | |
5710 | * 0 - success | |
5711 | * -EINVAL - backing format specified, but no file | |
5712 | * -ENOSPC - can't update the backing file because no space is left in the | |
5713 | * image file header | |
5714 | * -ENOTSUP - format driver doesn't support changing the backing file | |
5715 | */ | |
e54ee1b3 | 5716 | int bdrv_change_backing_file(BlockDriverState *bs, const char *backing_file, |
497a30db | 5717 | const char *backing_fmt, bool require) |
756e6736 KW |
5718 | { |
5719 | BlockDriver *drv = bs->drv; | |
469ef350 | 5720 | int ret; |
756e6736 | 5721 | |
f791bf7f EGE |
5722 | GLOBAL_STATE_CODE(); |
5723 | ||
d470ad42 HR |
5724 | if (!drv) { |
5725 | return -ENOMEDIUM; | |
5726 | } | |
5727 | ||
5f377794 PB |
5728 | /* Backing file format doesn't make sense without a backing file */ |
5729 | if (backing_fmt && !backing_file) { | |
5730 | return -EINVAL; | |
5731 | } | |
5732 | ||
497a30db EB |
5733 | if (require && backing_file && !backing_fmt) { |
5734 | return -EINVAL; | |
e54ee1b3 EB |
5735 | } |
5736 | ||
756e6736 | 5737 | if (drv->bdrv_change_backing_file != NULL) { |
469ef350 | 5738 | ret = drv->bdrv_change_backing_file(bs, backing_file, backing_fmt); |
756e6736 | 5739 | } else { |
469ef350 | 5740 | ret = -ENOTSUP; |
756e6736 | 5741 | } |
469ef350 PB |
5742 | |
5743 | if (ret == 0) { | |
5744 | pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); | |
5745 | pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); | |
998c2019 HR |
5746 | pstrcpy(bs->auto_backing_file, sizeof(bs->auto_backing_file), |
5747 | backing_file ?: ""); | |
469ef350 PB |
5748 | } |
5749 | return ret; | |
756e6736 KW |
5750 | } |
5751 | ||
6ebdcee2 | 5752 | /* |
dcf3f9b2 HR |
5753 | * Finds the first non-filter node above bs in the chain between |
5754 | * active and bs. The returned node is either an immediate parent of | |
5755 | * bs, or there are only filter nodes between the two. | |
6ebdcee2 JC |
5756 | * |
5757 | * Returns NULL if bs is not found in active's image chain, | |
5758 | * or if active == bs. | |
4caf0fcd JC |
5759 | * |
5760 | * Returns the bottommost base image if bs == NULL. | |
6ebdcee2 JC |
5761 | */ |
5762 | BlockDriverState *bdrv_find_overlay(BlockDriverState *active, | |
5763 | BlockDriverState *bs) | |
5764 | { | |
f791bf7f EGE |
5765 | |
5766 | GLOBAL_STATE_CODE(); | |
5767 | ||
dcf3f9b2 HR |
5768 | bs = bdrv_skip_filters(bs); |
5769 | active = bdrv_skip_filters(active); | |
5770 | ||
5771 | while (active) { | |
5772 | BlockDriverState *next = bdrv_backing_chain_next(active); | |
5773 | if (bs == next) { | |
5774 | return active; | |
5775 | } | |
5776 | active = next; | |
6ebdcee2 JC |
5777 | } |
5778 | ||
dcf3f9b2 | 5779 | return NULL; |
4caf0fcd | 5780 | } |
6ebdcee2 | 5781 | |
4caf0fcd JC |
5782 | /* Given a BDS, searches for the base layer. */ |
5783 | BlockDriverState *bdrv_find_base(BlockDriverState *bs) | |
5784 | { | |
f791bf7f EGE |
5785 | GLOBAL_STATE_CODE(); |
5786 | ||
4caf0fcd | 5787 | return bdrv_find_overlay(bs, NULL); |
6ebdcee2 JC |
5788 | } |
5789 | ||
2cad1ebe | 5790 | /* |
7b99a266 HR |
5791 | * Return true if at least one of the COW (backing) and filter links |
5792 | * between @bs and @base is frozen. @errp is set if that's the case. | |
0f0998f6 | 5793 | * @base must be reachable from @bs, or NULL. |
2cad1ebe AG |
5794 | */ |
5795 | bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base, | |
5796 | Error **errp) | |
5797 | { | |
5798 | BlockDriverState *i; | |
7b99a266 | 5799 | BdrvChild *child; |
2cad1ebe | 5800 | |
f791bf7f EGE |
5801 | GLOBAL_STATE_CODE(); |
5802 | ||
7b99a266 HR |
5803 | for (i = bs; i != base; i = child_bs(child)) { |
5804 | child = bdrv_filter_or_cow_child(i); | |
5805 | ||
5806 | if (child && child->frozen) { | |
2cad1ebe | 5807 | error_setg(errp, "Cannot change '%s' link from '%s' to '%s'", |
7b99a266 | 5808 | child->name, i->node_name, child->bs->node_name); |
2cad1ebe AG |
5809 | return true; |
5810 | } | |
5811 | } | |
5812 | ||
5813 | return false; | |
5814 | } | |
5815 | ||
5816 | /* | |
7b99a266 | 5817 | * Freeze all COW (backing) and filter links between @bs and @base. |
2cad1ebe AG |
5818 | * If any of the links is already frozen the operation is aborted and |
5819 | * none of the links are modified. | |
0f0998f6 | 5820 | * @base must be reachable from @bs, or NULL. |
2cad1ebe AG |
5821 | * Returns 0 on success. On failure returns < 0 and sets @errp. |
5822 | */ | |
5823 | int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base, | |
5824 | Error **errp) | |
5825 | { | |
5826 | BlockDriverState *i; | |
7b99a266 | 5827 | BdrvChild *child; |
2cad1ebe | 5828 | |
f791bf7f EGE |
5829 | GLOBAL_STATE_CODE(); |
5830 | ||
2cad1ebe AG |
5831 | if (bdrv_is_backing_chain_frozen(bs, base, errp)) { |
5832 | return -EPERM; | |
5833 | } | |
5834 | ||
7b99a266 HR |
5835 | for (i = bs; i != base; i = child_bs(child)) { |
5836 | child = bdrv_filter_or_cow_child(i); | |
5837 | if (child && child->bs->never_freeze) { | |
e5182c1c | 5838 | error_setg(errp, "Cannot freeze '%s' link to '%s'", |
7b99a266 | 5839 | child->name, child->bs->node_name); |
e5182c1c HR |
5840 | return -EPERM; |
5841 | } | |
5842 | } | |
5843 | ||
7b99a266 HR |
5844 | for (i = bs; i != base; i = child_bs(child)) { |
5845 | child = bdrv_filter_or_cow_child(i); | |
5846 | if (child) { | |
5847 | child->frozen = true; | |
0f0998f6 | 5848 | } |
2cad1ebe AG |
5849 | } |
5850 | ||
5851 | return 0; | |
5852 | } | |
5853 | ||
5854 | /* | |
7b99a266 HR |
5855 | * Unfreeze all COW (backing) and filter links between @bs and @base. |
5856 | * The caller must ensure that all links are frozen before using this | |
5857 | * function. | |
0f0998f6 | 5858 | * @base must be reachable from @bs, or NULL. |
2cad1ebe AG |
5859 | */ |
5860 | void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base) | |
5861 | { | |
5862 | BlockDriverState *i; | |
7b99a266 | 5863 | BdrvChild *child; |
2cad1ebe | 5864 | |
f791bf7f EGE |
5865 | GLOBAL_STATE_CODE(); |
5866 | ||
7b99a266 HR |
5867 | for (i = bs; i != base; i = child_bs(child)) { |
5868 | child = bdrv_filter_or_cow_child(i); | |
5869 | if (child) { | |
5870 | assert(child->frozen); | |
5871 | child->frozen = false; | |
0f0998f6 | 5872 | } |
2cad1ebe AG |
5873 | } |
5874 | } | |
5875 | ||
6ebdcee2 JC |
5876 | /* |
5877 | * Drops images above 'base' up to and including 'top', and sets the image | |
5878 | * above 'top' to have base as its backing file. | |
5879 | * | |
5880 | * Requires that the overlay to 'top' is opened r/w, so that the backing file | |
5881 | * information in 'bs' can be properly updated. | |
5882 | * | |
5883 | * E.g., this will convert the following chain: | |
5884 | * bottom <- base <- intermediate <- top <- active | |
5885 | * | |
5886 | * to | |
5887 | * | |
5888 | * bottom <- base <- active | |
5889 | * | |
5890 | * It is allowed for bottom==base, in which case it converts: | |
5891 | * | |
5892 | * base <- intermediate <- top <- active | |
5893 | * | |
5894 | * to | |
5895 | * | |
5896 | * base <- active | |
5897 | * | |
54e26900 JC |
5898 | * If backing_file_str is non-NULL, it will be used when modifying top's |
5899 | * overlay image metadata. | |
5900 | * | |
6ebdcee2 JC |
5901 | * Error conditions: |
5902 | * if active == top, that is considered an error | |
5903 | * | |
5904 | */ | |
bde70715 KW |
5905 | int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, |
5906 | const char *backing_file_str) | |
6ebdcee2 | 5907 | { |
6bd858b3 AG |
5908 | BlockDriverState *explicit_top = top; |
5909 | bool update_inherits_from; | |
d669ed6a | 5910 | BdrvChild *c; |
12fa4af6 | 5911 | Error *local_err = NULL; |
6ebdcee2 | 5912 | int ret = -EIO; |
d669ed6a VSO |
5913 | g_autoptr(GSList) updated_children = NULL; |
5914 | GSList *p; | |
6ebdcee2 | 5915 | |
f791bf7f EGE |
5916 | GLOBAL_STATE_CODE(); |
5917 | ||
6858eba0 | 5918 | bdrv_ref(top); |
631086de | 5919 | bdrv_drained_begin(base); |
6858eba0 | 5920 | |
6ebdcee2 JC |
5921 | if (!top->drv || !base->drv) { |
5922 | goto exit; | |
5923 | } | |
5924 | ||
5db15a57 KW |
5925 | /* Make sure that base is in the backing chain of top */ |
5926 | if (!bdrv_chain_contains(top, base)) { | |
6ebdcee2 JC |
5927 | goto exit; |
5928 | } | |
5929 | ||
6bd858b3 AG |
5930 | /* If 'base' recursively inherits from 'top' then we should set |
5931 | * base->inherits_from to top->inherits_from after 'top' and all | |
5932 | * other intermediate nodes have been dropped. | |
5933 | * If 'top' is an implicit node (e.g. "commit_top") we should skip | |
5934 | * it because no one inherits from it. We use explicit_top for that. */ | |
dcf3f9b2 | 5935 | explicit_top = bdrv_skip_implicit_filters(explicit_top); |
6bd858b3 AG |
5936 | update_inherits_from = bdrv_inherits_from_recursive(base, explicit_top); |
5937 | ||
6ebdcee2 | 5938 | /* success - we can delete the intermediate states, and link top->base */ |
f30c66ba HR |
5939 | if (!backing_file_str) { |
5940 | bdrv_refresh_filename(base); | |
5941 | backing_file_str = base->filename; | |
5942 | } | |
61f09cea | 5943 | |
733467a1 | 5944 | bdrv_graph_rdlock_main_loop(); |
d669ed6a VSO |
5945 | QLIST_FOREACH(c, &top->parents, next_parent) { |
5946 | updated_children = g_slist_prepend(updated_children, c); | |
5947 | } | |
733467a1 | 5948 | bdrv_graph_rdunlock_main_loop(); |
d669ed6a | 5949 | |
3108a15c VSO |
5950 | /* |
5951 | * It seems correct to pass detach_subchain=true here, but it triggers | |
5952 | * one more yet not fixed bug, when due to nested aio_poll loop we switch to | |
5953 | * another drained section, which modify the graph (for example, removing | |
5954 | * the child, which we keep in updated_children list). So, it's a TODO. | |
5955 | * | |
5956 | * Note, bug triggered if pass detach_subchain=true here and run | |
5957 | * test-bdrv-drain. test_drop_intermediate_poll() test-case will crash. | |
5958 | * That's a FIXME. | |
5959 | */ | |
5960 | bdrv_replace_node_common(top, base, false, false, &local_err); | |
d669ed6a VSO |
5961 | if (local_err) { |
5962 | error_report_err(local_err); | |
5963 | goto exit; | |
5964 | } | |
5965 | ||
5966 | for (p = updated_children; p; p = p->next) { | |
5967 | c = p->data; | |
12fa4af6 | 5968 | |
bd86fb99 HR |
5969 | if (c->klass->update_filename) { |
5970 | ret = c->klass->update_filename(c, base, backing_file_str, | |
5971 | &local_err); | |
61f09cea | 5972 | if (ret < 0) { |
d669ed6a VSO |
5973 | /* |
5974 | * TODO: Actually, we want to rollback all previous iterations | |
5975 | * of this loop, and (which is almost impossible) previous | |
5976 | * bdrv_replace_node()... | |
5977 | * | |
5978 | * Note, that c->klass->update_filename may lead to permission | |
5979 | * update, so it's a bad idea to call it inside permission | |
5980 | * update transaction of bdrv_replace_node. | |
5981 | */ | |
61f09cea KW |
5982 | error_report_err(local_err); |
5983 | goto exit; | |
5984 | } | |
5985 | } | |
12fa4af6 | 5986 | } |
6ebdcee2 | 5987 | |
6bd858b3 AG |
5988 | if (update_inherits_from) { |
5989 | base->inherits_from = explicit_top->inherits_from; | |
5990 | } | |
5991 | ||
6ebdcee2 | 5992 | ret = 0; |
6ebdcee2 | 5993 | exit: |
631086de | 5994 | bdrv_drained_end(base); |
6858eba0 | 5995 | bdrv_unref(top); |
6ebdcee2 JC |
5996 | return ret; |
5997 | } | |
5998 | ||
081e4650 | 5999 | /** |
82618d7b | 6000 | * Implementation of BlockDriver.bdrv_co_get_allocated_file_size() that |
081e4650 HR |
6001 | * sums the size of all data-bearing children. (This excludes backing |
6002 | * children.) | |
6003 | */ | |
de335638 EGE |
6004 | static int64_t coroutine_fn GRAPH_RDLOCK |
6005 | bdrv_sum_allocated_file_size(BlockDriverState *bs) | |
081e4650 HR |
6006 | { |
6007 | BdrvChild *child; | |
6008 | int64_t child_size, sum = 0; | |
6009 | ||
6010 | QLIST_FOREACH(child, &bs->children, next) { | |
6011 | if (child->role & (BDRV_CHILD_DATA | BDRV_CHILD_METADATA | | |
6012 | BDRV_CHILD_FILTERED)) | |
6013 | { | |
82618d7b | 6014 | child_size = bdrv_co_get_allocated_file_size(child->bs); |
081e4650 HR |
6015 | if (child_size < 0) { |
6016 | return child_size; | |
6017 | } | |
6018 | sum += child_size; | |
6019 | } | |
6020 | } | |
6021 | ||
6022 | return sum; | |
6023 | } | |
6024 | ||
61007b31 SH |
6025 | /** |
6026 | * Length of a allocated file in bytes. Sparse files are counted by actual | |
6027 | * allocated space. Return < 0 if error or unknown. | |
6028 | */ | |
82618d7b | 6029 | int64_t coroutine_fn bdrv_co_get_allocated_file_size(BlockDriverState *bs) |
71d0770c | 6030 | { |
61007b31 | 6031 | BlockDriver *drv = bs->drv; |
384a48fb | 6032 | IO_CODE(); |
de335638 | 6033 | assert_bdrv_graph_readable(); |
384a48fb | 6034 | |
61007b31 SH |
6035 | if (!drv) { |
6036 | return -ENOMEDIUM; | |
8f4754ed | 6037 | } |
82618d7b EGE |
6038 | if (drv->bdrv_co_get_allocated_file_size) { |
6039 | return drv->bdrv_co_get_allocated_file_size(bs); | |
61007b31 | 6040 | } |
081e4650 HR |
6041 | |
6042 | if (drv->bdrv_file_open) { | |
6043 | /* | |
6044 | * Protocol drivers default to -ENOTSUP (most of their data is | |
6045 | * not stored in any of their children (if they even have any), | |
6046 | * so there is no generic way to figure it out). | |
6047 | */ | |
6048 | return -ENOTSUP; | |
6049 | } else if (drv->is_filter) { | |
6050 | /* Filter drivers default to the size of their filtered child */ | |
82618d7b | 6051 | return bdrv_co_get_allocated_file_size(bdrv_filter_bs(bs)); |
081e4650 HR |
6052 | } else { |
6053 | /* Other drivers default to summing their children's sizes */ | |
6054 | return bdrv_sum_allocated_file_size(bs); | |
1c9805a3 SH |
6055 | } |
6056 | } | |
e7a8a783 | 6057 | |
90880ff1 SH |
6058 | /* |
6059 | * bdrv_measure: | |
6060 | * @drv: Format driver | |
6061 | * @opts: Creation options for new image | |
6062 | * @in_bs: Existing image containing data for new image (may be NULL) | |
6063 | * @errp: Error object | |
6064 | * Returns: A #BlockMeasureInfo (free using qapi_free_BlockMeasureInfo()) | |
6065 | * or NULL on error | |
6066 | * | |
6067 | * Calculate file size required to create a new image. | |
6068 | * | |
6069 | * If @in_bs is given then space for allocated clusters and zero clusters | |
6070 | * from that image are included in the calculation. If @opts contains a | |
6071 | * backing file that is shared by @in_bs then backing clusters may be omitted | |
6072 | * from the calculation. | |
6073 | * | |
6074 | * If @in_bs is NULL then the calculation includes no allocated clusters | |
6075 | * unless a preallocation option is given in @opts. | |
6076 | * | |
6077 | * Note that @in_bs may use a different BlockDriver from @drv. | |
6078 | * | |
6079 | * If an error occurs the @errp pointer is set. | |
6080 | */ | |
6081 | BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, | |
6082 | BlockDriverState *in_bs, Error **errp) | |
6083 | { | |
384a48fb | 6084 | IO_CODE(); |
90880ff1 SH |
6085 | if (!drv->bdrv_measure) { |
6086 | error_setg(errp, "Block driver '%s' does not support size measurement", | |
6087 | drv->format_name); | |
6088 | return NULL; | |
6089 | } | |
6090 | ||
6091 | return drv->bdrv_measure(opts, in_bs, errp); | |
6092 | } | |
6093 | ||
61007b31 SH |
6094 | /** |
6095 | * Return number of sectors on success, -errno on error. | |
1c9805a3 | 6096 | */ |
c86422c5 | 6097 | int64_t coroutine_fn bdrv_co_nb_sectors(BlockDriverState *bs) |
1c9805a3 | 6098 | { |
61007b31 | 6099 | BlockDriver *drv = bs->drv; |
384a48fb | 6100 | IO_CODE(); |
8ab8140a | 6101 | assert_bdrv_graph_readable(); |
498e386c | 6102 | |
61007b31 SH |
6103 | if (!drv) |
6104 | return -ENOMEDIUM; | |
2572b37a | 6105 | |
160a29e2 | 6106 | if (bs->bl.has_variable_length) { |
c86422c5 | 6107 | int ret = bdrv_co_refresh_total_sectors(bs, bs->total_sectors); |
61007b31 SH |
6108 | if (ret < 0) { |
6109 | return ret; | |
1c9805a3 SH |
6110 | } |
6111 | } | |
61007b31 | 6112 | return bs->total_sectors; |
1c9805a3 | 6113 | } |
b338082b | 6114 | |
81f730d4 PB |
6115 | /* |
6116 | * This wrapper is written by hand because this function is in the hot I/O path, | |
6117 | * via blk_get_geometry. | |
6118 | */ | |
6119 | int64_t coroutine_mixed_fn bdrv_nb_sectors(BlockDriverState *bs) | |
6120 | { | |
6121 | BlockDriver *drv = bs->drv; | |
6122 | IO_CODE(); | |
6123 | ||
6124 | if (!drv) | |
6125 | return -ENOMEDIUM; | |
6126 | ||
6127 | if (bs->bl.has_variable_length) { | |
6128 | int ret = bdrv_refresh_total_sectors(bs, bs->total_sectors); | |
6129 | if (ret < 0) { | |
6130 | return ret; | |
6131 | } | |
6132 | } | |
6133 | ||
6134 | return bs->total_sectors; | |
6135 | } | |
6136 | ||
61007b31 SH |
6137 | /** |
6138 | * Return length in bytes on success, -errno on error. | |
6139 | * The length is always a multiple of BDRV_SECTOR_SIZE. | |
8d3b1a2d | 6140 | */ |
c86422c5 | 6141 | int64_t coroutine_fn bdrv_co_getlength(BlockDriverState *bs) |
8d3b1a2d | 6142 | { |
c86422c5 | 6143 | int64_t ret; |
384a48fb | 6144 | IO_CODE(); |
8ab8140a | 6145 | assert_bdrv_graph_readable(); |
8d3b1a2d | 6146 | |
c86422c5 | 6147 | ret = bdrv_co_nb_sectors(bs); |
122860ba EB |
6148 | if (ret < 0) { |
6149 | return ret; | |
6150 | } | |
6151 | if (ret > INT64_MAX / BDRV_SECTOR_SIZE) { | |
6152 | return -EFBIG; | |
6153 | } | |
6154 | return ret * BDRV_SECTOR_SIZE; | |
fc01f7e7 FB |
6155 | } |
6156 | ||
54115412 | 6157 | bool bdrv_is_sg(BlockDriverState *bs) |
f08145fe | 6158 | { |
384a48fb | 6159 | IO_CODE(); |
61007b31 | 6160 | return bs->sg; |
f08145fe KW |
6161 | } |
6162 | ||
ae23f786 HR |
6163 | /** |
6164 | * Return whether the given node supports compressed writes. | |
6165 | */ | |
6166 | bool bdrv_supports_compressed_writes(BlockDriverState *bs) | |
6167 | { | |
6168 | BlockDriverState *filtered; | |
384a48fb | 6169 | IO_CODE(); |
ae23f786 HR |
6170 | |
6171 | if (!bs->drv || !block_driver_can_compress(bs->drv)) { | |
6172 | return false; | |
6173 | } | |
6174 | ||
6175 | filtered = bdrv_filter_bs(bs); | |
6176 | if (filtered) { | |
6177 | /* | |
6178 | * Filters can only forward compressed writes, so we have to | |
6179 | * check the child. | |
6180 | */ | |
6181 | return bdrv_supports_compressed_writes(filtered); | |
6182 | } | |
6183 | ||
6184 | return true; | |
6185 | } | |
6186 | ||
61007b31 | 6187 | const char *bdrv_get_format_name(BlockDriverState *bs) |
40b4f539 | 6188 | { |
384a48fb | 6189 | IO_CODE(); |
61007b31 | 6190 | return bs->drv ? bs->drv->format_name : NULL; |
40b4f539 KW |
6191 | } |
6192 | ||
61007b31 | 6193 | static int qsort_strcmp(const void *a, const void *b) |
40b4f539 | 6194 | { |
ceff5bd7 | 6195 | return strcmp(*(char *const *)a, *(char *const *)b); |
40b4f539 KW |
6196 | } |
6197 | ||
61007b31 | 6198 | void bdrv_iterate_format(void (*it)(void *opaque, const char *name), |
9ac404c5 | 6199 | void *opaque, bool read_only) |
40b4f539 | 6200 | { |
61007b31 SH |
6201 | BlockDriver *drv; |
6202 | int count = 0; | |
6203 | int i; | |
6204 | const char **formats = NULL; | |
40b4f539 | 6205 | |
f791bf7f EGE |
6206 | GLOBAL_STATE_CODE(); |
6207 | ||
61007b31 SH |
6208 | QLIST_FOREACH(drv, &bdrv_drivers, list) { |
6209 | if (drv->format_name) { | |
6210 | bool found = false; | |
6211 | int i = count; | |
9ac404c5 AS |
6212 | |
6213 | if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, read_only)) { | |
6214 | continue; | |
6215 | } | |
6216 | ||
61007b31 SH |
6217 | while (formats && i && !found) { |
6218 | found = !strcmp(formats[--i], drv->format_name); | |
6219 | } | |
e2a305fb | 6220 | |
61007b31 SH |
6221 | if (!found) { |
6222 | formats = g_renew(const char *, formats, count + 1); | |
6223 | formats[count++] = drv->format_name; | |
6224 | } | |
6c5a42ac | 6225 | } |
61007b31 | 6226 | } |
6c5a42ac | 6227 | |
eb0df69f HR |
6228 | for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); i++) { |
6229 | const char *format_name = block_driver_modules[i].format_name; | |
6230 | ||
6231 | if (format_name) { | |
6232 | bool found = false; | |
6233 | int j = count; | |
6234 | ||
9ac404c5 AS |
6235 | if (use_bdrv_whitelist && |
6236 | !bdrv_format_is_whitelisted(format_name, read_only)) { | |
6237 | continue; | |
6238 | } | |
6239 | ||
eb0df69f HR |
6240 | while (formats && j && !found) { |
6241 | found = !strcmp(formats[--j], format_name); | |
6242 | } | |
6243 | ||
6244 | if (!found) { | |
6245 | formats = g_renew(const char *, formats, count + 1); | |
6246 | formats[count++] = format_name; | |
6247 | } | |
6248 | } | |
6249 | } | |
6250 | ||
61007b31 | 6251 | qsort(formats, count, sizeof(formats[0]), qsort_strcmp); |
40b4f539 | 6252 | |
61007b31 SH |
6253 | for (i = 0; i < count; i++) { |
6254 | it(opaque, formats[i]); | |
6255 | } | |
40b4f539 | 6256 | |
61007b31 SH |
6257 | g_free(formats); |
6258 | } | |
40b4f539 | 6259 | |
61007b31 SH |
6260 | /* This function is to find a node in the bs graph */ |
6261 | BlockDriverState *bdrv_find_node(const char *node_name) | |
6262 | { | |
6263 | BlockDriverState *bs; | |
391827eb | 6264 | |
61007b31 | 6265 | assert(node_name); |
f791bf7f | 6266 | GLOBAL_STATE_CODE(); |
40b4f539 | 6267 | |
61007b31 SH |
6268 | QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) { |
6269 | if (!strcmp(node_name, bs->node_name)) { | |
6270 | return bs; | |
40b4f539 KW |
6271 | } |
6272 | } | |
61007b31 | 6273 | return NULL; |
40b4f539 KW |
6274 | } |
6275 | ||
61007b31 | 6276 | /* Put this QMP function here so it can access the static graph_bdrv_states. */ |
facda544 PK |
6277 | BlockDeviceInfoList *bdrv_named_nodes_list(bool flat, |
6278 | Error **errp) | |
40b4f539 | 6279 | { |
9812e712 | 6280 | BlockDeviceInfoList *list; |
61007b31 | 6281 | BlockDriverState *bs; |
40b4f539 | 6282 | |
f791bf7f EGE |
6283 | GLOBAL_STATE_CODE(); |
6284 | ||
61007b31 SH |
6285 | list = NULL; |
6286 | QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) { | |
facda544 | 6287 | BlockDeviceInfo *info = bdrv_block_device_info(NULL, bs, flat, errp); |
61007b31 SH |
6288 | if (!info) { |
6289 | qapi_free_BlockDeviceInfoList(list); | |
6290 | return NULL; | |
301db7c2 | 6291 | } |
9812e712 | 6292 | QAPI_LIST_PREPEND(list, info); |
301db7c2 RH |
6293 | } |
6294 | ||
61007b31 SH |
6295 | return list; |
6296 | } | |
40b4f539 | 6297 | |
5d3b4e99 VSO |
6298 | typedef struct XDbgBlockGraphConstructor { |
6299 | XDbgBlockGraph *graph; | |
6300 | GHashTable *graph_nodes; | |
6301 | } XDbgBlockGraphConstructor; | |
6302 | ||
6303 | static XDbgBlockGraphConstructor *xdbg_graph_new(void) | |
6304 | { | |
6305 | XDbgBlockGraphConstructor *gr = g_new(XDbgBlockGraphConstructor, 1); | |
6306 | ||
6307 | gr->graph = g_new0(XDbgBlockGraph, 1); | |
6308 | gr->graph_nodes = g_hash_table_new(NULL, NULL); | |
6309 | ||
6310 | return gr; | |
6311 | } | |
6312 | ||
6313 | static XDbgBlockGraph *xdbg_graph_finalize(XDbgBlockGraphConstructor *gr) | |
6314 | { | |
6315 | XDbgBlockGraph *graph = gr->graph; | |
6316 | ||
6317 | g_hash_table_destroy(gr->graph_nodes); | |
6318 | g_free(gr); | |
6319 | ||
6320 | return graph; | |
6321 | } | |
6322 | ||
6323 | static uintptr_t xdbg_graph_node_num(XDbgBlockGraphConstructor *gr, void *node) | |
6324 | { | |
6325 | uintptr_t ret = (uintptr_t)g_hash_table_lookup(gr->graph_nodes, node); | |
6326 | ||
6327 | if (ret != 0) { | |
6328 | return ret; | |
6329 | } | |
6330 | ||
6331 | /* | |
6332 | * Start counting from 1, not 0, because 0 interferes with not-found (NULL) | |
6333 | * answer of g_hash_table_lookup. | |
6334 | */ | |
6335 | ret = g_hash_table_size(gr->graph_nodes) + 1; | |
6336 | g_hash_table_insert(gr->graph_nodes, node, (void *)ret); | |
6337 | ||
6338 | return ret; | |
6339 | } | |
6340 | ||
6341 | static void xdbg_graph_add_node(XDbgBlockGraphConstructor *gr, void *node, | |
6342 | XDbgBlockGraphNodeType type, const char *name) | |
6343 | { | |
6344 | XDbgBlockGraphNode *n; | |
6345 | ||
6346 | n = g_new0(XDbgBlockGraphNode, 1); | |
6347 | ||
6348 | n->id = xdbg_graph_node_num(gr, node); | |
6349 | n->type = type; | |
6350 | n->name = g_strdup(name); | |
6351 | ||
9812e712 | 6352 | QAPI_LIST_PREPEND(gr->graph->nodes, n); |
5d3b4e99 VSO |
6353 | } |
6354 | ||
6355 | static void xdbg_graph_add_edge(XDbgBlockGraphConstructor *gr, void *parent, | |
6356 | const BdrvChild *child) | |
6357 | { | |
cdb1cec8 | 6358 | BlockPermission qapi_perm; |
5d3b4e99 | 6359 | XDbgBlockGraphEdge *edge; |
862fded9 | 6360 | GLOBAL_STATE_CODE(); |
5d3b4e99 | 6361 | |
5d3b4e99 VSO |
6362 | edge = g_new0(XDbgBlockGraphEdge, 1); |
6363 | ||
6364 | edge->parent = xdbg_graph_node_num(gr, parent); | |
6365 | edge->child = xdbg_graph_node_num(gr, child->bs); | |
6366 | edge->name = g_strdup(child->name); | |
6367 | ||
cdb1cec8 HR |
6368 | for (qapi_perm = 0; qapi_perm < BLOCK_PERMISSION__MAX; qapi_perm++) { |
6369 | uint64_t flag = bdrv_qapi_perm_to_blk_perm(qapi_perm); | |
6370 | ||
6371 | if (flag & child->perm) { | |
9812e712 | 6372 | QAPI_LIST_PREPEND(edge->perm, qapi_perm); |
5d3b4e99 | 6373 | } |
cdb1cec8 | 6374 | if (flag & child->shared_perm) { |
9812e712 | 6375 | QAPI_LIST_PREPEND(edge->shared_perm, qapi_perm); |
5d3b4e99 VSO |
6376 | } |
6377 | } | |
6378 | ||
9812e712 | 6379 | QAPI_LIST_PREPEND(gr->graph->edges, edge); |
5d3b4e99 VSO |
6380 | } |
6381 | ||
6382 | ||
6383 | XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp) | |
6384 | { | |
6385 | BlockBackend *blk; | |
6386 | BlockJob *job; | |
6387 | BlockDriverState *bs; | |
6388 | BdrvChild *child; | |
6389 | XDbgBlockGraphConstructor *gr = xdbg_graph_new(); | |
6390 | ||
f791bf7f EGE |
6391 | GLOBAL_STATE_CODE(); |
6392 | ||
5d3b4e99 VSO |
6393 | for (blk = blk_all_next(NULL); blk; blk = blk_all_next(blk)) { |
6394 | char *allocated_name = NULL; | |
6395 | const char *name = blk_name(blk); | |
6396 | ||
6397 | if (!*name) { | |
6398 | name = allocated_name = blk_get_attached_dev_id(blk); | |
6399 | } | |
6400 | xdbg_graph_add_node(gr, blk, X_DBG_BLOCK_GRAPH_NODE_TYPE_BLOCK_BACKEND, | |
6401 | name); | |
6402 | g_free(allocated_name); | |
6403 | if (blk_root(blk)) { | |
6404 | xdbg_graph_add_edge(gr, blk, blk_root(blk)); | |
6405 | } | |
6406 | } | |
6407 | ||
880eeec6 EGE |
6408 | WITH_JOB_LOCK_GUARD() { |
6409 | for (job = block_job_next_locked(NULL); job; | |
6410 | job = block_job_next_locked(job)) { | |
6411 | GSList *el; | |
5d3b4e99 | 6412 | |
880eeec6 EGE |
6413 | xdbg_graph_add_node(gr, job, X_DBG_BLOCK_GRAPH_NODE_TYPE_BLOCK_JOB, |
6414 | job->job.id); | |
6415 | for (el = job->nodes; el; el = el->next) { | |
6416 | xdbg_graph_add_edge(gr, job, (BdrvChild *)el->data); | |
6417 | } | |
5d3b4e99 VSO |
6418 | } |
6419 | } | |
6420 | ||
6421 | QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) { | |
6422 | xdbg_graph_add_node(gr, bs, X_DBG_BLOCK_GRAPH_NODE_TYPE_BLOCK_DRIVER, | |
6423 | bs->node_name); | |
6424 | QLIST_FOREACH(child, &bs->children, next) { | |
6425 | xdbg_graph_add_edge(gr, bs, child); | |
6426 | } | |
6427 | } | |
6428 | ||
6429 | return xdbg_graph_finalize(gr); | |
6430 | } | |
6431 | ||
61007b31 SH |
6432 | BlockDriverState *bdrv_lookup_bs(const char *device, |
6433 | const char *node_name, | |
6434 | Error **errp) | |
6435 | { | |
6436 | BlockBackend *blk; | |
6437 | BlockDriverState *bs; | |
40b4f539 | 6438 | |
f791bf7f EGE |
6439 | GLOBAL_STATE_CODE(); |
6440 | ||
61007b31 SH |
6441 | if (device) { |
6442 | blk = blk_by_name(device); | |
40b4f539 | 6443 | |
61007b31 | 6444 | if (blk) { |
9f4ed6fb AG |
6445 | bs = blk_bs(blk); |
6446 | if (!bs) { | |
5433c24f | 6447 | error_setg(errp, "Device '%s' has no medium", device); |
5433c24f HR |
6448 | } |
6449 | ||
9f4ed6fb | 6450 | return bs; |
61007b31 SH |
6451 | } |
6452 | } | |
40b4f539 | 6453 | |
61007b31 SH |
6454 | if (node_name) { |
6455 | bs = bdrv_find_node(node_name); | |
6d519a5f | 6456 | |
61007b31 SH |
6457 | if (bs) { |
6458 | return bs; | |
6459 | } | |
40b4f539 KW |
6460 | } |
6461 | ||
785ec4b1 | 6462 | error_setg(errp, "Cannot find device=\'%s\' nor node-name=\'%s\'", |
61007b31 SH |
6463 | device ? device : "", |
6464 | node_name ? node_name : ""); | |
6465 | return NULL; | |
40b4f539 KW |
6466 | } |
6467 | ||
61007b31 SH |
6468 | /* If 'base' is in the same chain as 'top', return true. Otherwise, |
6469 | * return false. If either argument is NULL, return false. */ | |
6470 | bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base) | |
83f64091 | 6471 | { |
f791bf7f EGE |
6472 | |
6473 | GLOBAL_STATE_CODE(); | |
6474 | ||
61007b31 | 6475 | while (top && top != base) { |
dcf3f9b2 | 6476 | top = bdrv_filter_or_cow_bs(top); |
02c50efe | 6477 | } |
61007b31 SH |
6478 | |
6479 | return top != NULL; | |
02c50efe FZ |
6480 | } |
6481 | ||
61007b31 | 6482 | BlockDriverState *bdrv_next_node(BlockDriverState *bs) |
02c50efe | 6483 | { |
f791bf7f | 6484 | GLOBAL_STATE_CODE(); |
61007b31 SH |
6485 | if (!bs) { |
6486 | return QTAILQ_FIRST(&graph_bdrv_states); | |
02c50efe | 6487 | } |
61007b31 | 6488 | return QTAILQ_NEXT(bs, node_list); |
83f64091 FB |
6489 | } |
6490 | ||
0f12264e KW |
6491 | BlockDriverState *bdrv_next_all_states(BlockDriverState *bs) |
6492 | { | |
f791bf7f | 6493 | GLOBAL_STATE_CODE(); |
0f12264e KW |
6494 | if (!bs) { |
6495 | return QTAILQ_FIRST(&all_bdrv_states); | |
6496 | } | |
6497 | return QTAILQ_NEXT(bs, bs_list); | |
6498 | } | |
6499 | ||
61007b31 | 6500 | const char *bdrv_get_node_name(const BlockDriverState *bs) |
83f64091 | 6501 | { |
384a48fb | 6502 | IO_CODE(); |
61007b31 | 6503 | return bs->node_name; |
beac80cd FB |
6504 | } |
6505 | ||
1f0c461b | 6506 | const char *bdrv_get_parent_name(const BlockDriverState *bs) |
4c265bf9 KW |
6507 | { |
6508 | BdrvChild *c; | |
6509 | const char *name; | |
967d7905 | 6510 | IO_CODE(); |
4c265bf9 KW |
6511 | |
6512 | /* If multiple parents have a name, just pick the first one. */ | |
6513 | QLIST_FOREACH(c, &bs->parents, next_parent) { | |
bd86fb99 HR |
6514 | if (c->klass->get_name) { |
6515 | name = c->klass->get_name(c); | |
4c265bf9 KW |
6516 | if (name && *name) { |
6517 | return name; | |
6518 | } | |
6519 | } | |
6520 | } | |
6521 | ||
6522 | return NULL; | |
6523 | } | |
6524 | ||
61007b31 SH |
6525 | /* TODO check what callers really want: bs->node_name or blk_name() */ |
6526 | const char *bdrv_get_device_name(const BlockDriverState *bs) | |
beac80cd | 6527 | { |
384a48fb | 6528 | IO_CODE(); |
4c265bf9 | 6529 | return bdrv_get_parent_name(bs) ?: ""; |
f141eafe | 6530 | } |
83f64091 | 6531 | |
61007b31 SH |
6532 | /* This can be used to identify nodes that might not have a device |
6533 | * name associated. Since node and device names live in the same | |
6534 | * namespace, the result is unambiguous. The exception is if both are | |
6535 | * absent, then this returns an empty (non-null) string. */ | |
6536 | const char *bdrv_get_device_or_node_name(const BlockDriverState *bs) | |
f141eafe | 6537 | { |
384a48fb | 6538 | IO_CODE(); |
4c265bf9 | 6539 | return bdrv_get_parent_name(bs) ?: bs->node_name; |
beac80cd | 6540 | } |
beac80cd | 6541 | |
61007b31 | 6542 | int bdrv_get_flags(BlockDriverState *bs) |
0b5a2445 | 6543 | { |
15aee7ac | 6544 | IO_CODE(); |
61007b31 | 6545 | return bs->open_flags; |
0b5a2445 PB |
6546 | } |
6547 | ||
61007b31 | 6548 | int bdrv_has_zero_init_1(BlockDriverState *bs) |
68485420 | 6549 | { |
f791bf7f | 6550 | GLOBAL_STATE_CODE(); |
61007b31 | 6551 | return 1; |
0b5a2445 PB |
6552 | } |
6553 | ||
61007b31 | 6554 | int bdrv_has_zero_init(BlockDriverState *bs) |
0b5a2445 | 6555 | { |
93393e69 | 6556 | BlockDriverState *filtered; |
f791bf7f | 6557 | GLOBAL_STATE_CODE(); |
93393e69 | 6558 | |
d470ad42 HR |
6559 | if (!bs->drv) { |
6560 | return 0; | |
6561 | } | |
0b5a2445 | 6562 | |
61007b31 SH |
6563 | /* If BS is a copy on write image, it is initialized to |
6564 | the contents of the base image, which may not be zeroes. */ | |
34778172 | 6565 | if (bdrv_cow_child(bs)) { |
61007b31 SH |
6566 | return 0; |
6567 | } | |
6568 | if (bs->drv->bdrv_has_zero_init) { | |
6569 | return bs->drv->bdrv_has_zero_init(bs); | |
0b5a2445 | 6570 | } |
93393e69 HR |
6571 | |
6572 | filtered = bdrv_filter_bs(bs); | |
6573 | if (filtered) { | |
6574 | return bdrv_has_zero_init(filtered); | |
5a612c00 | 6575 | } |
61007b31 SH |
6576 | |
6577 | /* safe default */ | |
6578 | return 0; | |
68485420 KW |
6579 | } |
6580 | ||
61007b31 | 6581 | bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs) |
68485420 | 6582 | { |
384a48fb | 6583 | IO_CODE(); |
2f0342ef | 6584 | if (!(bs->open_flags & BDRV_O_UNMAP)) { |
61007b31 SH |
6585 | return false; |
6586 | } | |
68485420 | 6587 | |
e24d813b | 6588 | return bs->supported_zero_flags & BDRV_REQ_MAY_UNMAP; |
68485420 KW |
6589 | } |
6590 | ||
61007b31 SH |
6591 | void bdrv_get_backing_filename(BlockDriverState *bs, |
6592 | char *filename, int filename_size) | |
016f5cf6 | 6593 | { |
384a48fb | 6594 | IO_CODE(); |
61007b31 SH |
6595 | pstrcpy(filename, filename_size, bs->backing_file); |
6596 | } | |
d318aea9 | 6597 | |
3d47eb0a | 6598 | int coroutine_fn bdrv_co_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
61007b31 | 6599 | { |
8b117001 | 6600 | int ret; |
61007b31 | 6601 | BlockDriver *drv = bs->drv; |
384a48fb | 6602 | IO_CODE(); |
a00e70c0 EGE |
6603 | assert_bdrv_graph_readable(); |
6604 | ||
5a612c00 MP |
6605 | /* if bs->drv == NULL, bs is closed, so there's nothing to do here */ |
6606 | if (!drv) { | |
61007b31 | 6607 | return -ENOMEDIUM; |
5a612c00 | 6608 | } |
3d47eb0a | 6609 | if (!drv->bdrv_co_get_info) { |
93393e69 HR |
6610 | BlockDriverState *filtered = bdrv_filter_bs(bs); |
6611 | if (filtered) { | |
3d47eb0a | 6612 | return bdrv_co_get_info(filtered, bdi); |
5a612c00 | 6613 | } |
61007b31 | 6614 | return -ENOTSUP; |
5a612c00 | 6615 | } |
61007b31 | 6616 | memset(bdi, 0, sizeof(*bdi)); |
3d47eb0a | 6617 | ret = drv->bdrv_co_get_info(bs, bdi); |
c54483b6 AD |
6618 | if (bdi->subcluster_size == 0) { |
6619 | /* | |
6620 | * If the driver left this unset, subclusters are not supported. | |
6621 | * Then it is safe to treat each cluster as having only one subcluster. | |
6622 | */ | |
6623 | bdi->subcluster_size = bdi->cluster_size; | |
6624 | } | |
8b117001 VSO |
6625 | if (ret < 0) { |
6626 | return ret; | |
6627 | } | |
6628 | ||
6629 | if (bdi->cluster_size > BDRV_MAX_ALIGNMENT) { | |
6630 | return -EINVAL; | |
6631 | } | |
6632 | ||
6633 | return 0; | |
61007b31 | 6634 | } |
016f5cf6 | 6635 | |
1bf6e9ca AS |
6636 | ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs, |
6637 | Error **errp) | |
61007b31 SH |
6638 | { |
6639 | BlockDriver *drv = bs->drv; | |
384a48fb | 6640 | IO_CODE(); |
61007b31 | 6641 | if (drv && drv->bdrv_get_specific_info) { |
1bf6e9ca | 6642 | return drv->bdrv_get_specific_info(bs, errp); |
61007b31 SH |
6643 | } |
6644 | return NULL; | |
016f5cf6 AG |
6645 | } |
6646 | ||
d9245599 AN |
6647 | BlockStatsSpecific *bdrv_get_specific_stats(BlockDriverState *bs) |
6648 | { | |
6649 | BlockDriver *drv = bs->drv; | |
384a48fb | 6650 | IO_CODE(); |
d9245599 AN |
6651 | if (!drv || !drv->bdrv_get_specific_stats) { |
6652 | return NULL; | |
6653 | } | |
6654 | return drv->bdrv_get_specific_stats(bs); | |
6655 | } | |
6656 | ||
c834dc05 | 6657 | void coroutine_fn bdrv_co_debug_event(BlockDriverState *bs, BlkdebugEvent event) |
4265d620 | 6658 | { |
384a48fb | 6659 | IO_CODE(); |
cb2bfaa4 EGE |
6660 | assert_bdrv_graph_readable(); |
6661 | ||
c834dc05 | 6662 | if (!bs || !bs->drv || !bs->drv->bdrv_co_debug_event) { |
61007b31 SH |
6663 | return; |
6664 | } | |
4265d620 | 6665 | |
c834dc05 | 6666 | bs->drv->bdrv_co_debug_event(bs, event); |
4265d620 PB |
6667 | } |
6668 | ||
d10529a2 | 6669 | static BlockDriverState *bdrv_find_debug_node(BlockDriverState *bs) |
4265d620 | 6670 | { |
bdb73476 | 6671 | GLOBAL_STATE_CODE(); |
61007b31 | 6672 | while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) { |
f706a92f | 6673 | bs = bdrv_primary_bs(bs); |
61007b31 | 6674 | } |
4265d620 | 6675 | |
61007b31 | 6676 | if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) { |
d10529a2 VSO |
6677 | assert(bs->drv->bdrv_debug_remove_breakpoint); |
6678 | return bs; | |
6679 | } | |
6680 | ||
6681 | return NULL; | |
6682 | } | |
6683 | ||
6684 | int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, | |
6685 | const char *tag) | |
6686 | { | |
f791bf7f | 6687 | GLOBAL_STATE_CODE(); |
d10529a2 VSO |
6688 | bs = bdrv_find_debug_node(bs); |
6689 | if (bs) { | |
61007b31 SH |
6690 | return bs->drv->bdrv_debug_breakpoint(bs, event, tag); |
6691 | } | |
4265d620 | 6692 | |
61007b31 | 6693 | return -ENOTSUP; |
4265d620 PB |
6694 | } |
6695 | ||
61007b31 | 6696 | int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag) |
ea2384d3 | 6697 | { |
f791bf7f | 6698 | GLOBAL_STATE_CODE(); |
d10529a2 VSO |
6699 | bs = bdrv_find_debug_node(bs); |
6700 | if (bs) { | |
61007b31 SH |
6701 | return bs->drv->bdrv_debug_remove_breakpoint(bs, tag); |
6702 | } | |
6703 | ||
6704 | return -ENOTSUP; | |
eb852011 MA |
6705 | } |
6706 | ||
61007b31 | 6707 | int bdrv_debug_resume(BlockDriverState *bs, const char *tag) |
ce1a14dc | 6708 | { |
f791bf7f | 6709 | GLOBAL_STATE_CODE(); |
61007b31 | 6710 | while (bs && (!bs->drv || !bs->drv->bdrv_debug_resume)) { |
f706a92f | 6711 | bs = bdrv_primary_bs(bs); |
61007b31 | 6712 | } |
ce1a14dc | 6713 | |
61007b31 SH |
6714 | if (bs && bs->drv && bs->drv->bdrv_debug_resume) { |
6715 | return bs->drv->bdrv_debug_resume(bs, tag); | |
6716 | } | |
ce1a14dc | 6717 | |
61007b31 | 6718 | return -ENOTSUP; |
f197fe2b FZ |
6719 | } |
6720 | ||
61007b31 | 6721 | bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag) |
ce1a14dc | 6722 | { |
f791bf7f | 6723 | GLOBAL_STATE_CODE(); |
61007b31 | 6724 | while (bs && bs->drv && !bs->drv->bdrv_debug_is_suspended) { |
f706a92f | 6725 | bs = bdrv_primary_bs(bs); |
f197fe2b | 6726 | } |
19cb3738 | 6727 | |
61007b31 SH |
6728 | if (bs && bs->drv && bs->drv->bdrv_debug_is_suspended) { |
6729 | return bs->drv->bdrv_debug_is_suspended(bs, tag); | |
6730 | } | |
f9f05dc5 | 6731 | |
61007b31 SH |
6732 | return false; |
6733 | } | |
f9f05dc5 | 6734 | |
61007b31 SH |
6735 | /* backing_file can either be relative, or absolute, or a protocol. If it is |
6736 | * relative, it must be relative to the chain. So, passing in bs->filename | |
6737 | * from a BDS as backing_file should not be done, as that may be relative to | |
6738 | * the CWD rather than the chain. */ | |
6739 | BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, | |
6740 | const char *backing_file) | |
f9f05dc5 | 6741 | { |
61007b31 SH |
6742 | char *filename_full = NULL; |
6743 | char *backing_file_full = NULL; | |
6744 | char *filename_tmp = NULL; | |
6745 | int is_protocol = 0; | |
0b877d09 | 6746 | bool filenames_refreshed = false; |
61007b31 SH |
6747 | BlockDriverState *curr_bs = NULL; |
6748 | BlockDriverState *retval = NULL; | |
dcf3f9b2 | 6749 | BlockDriverState *bs_below; |
f9f05dc5 | 6750 | |
f791bf7f EGE |
6751 | GLOBAL_STATE_CODE(); |
6752 | ||
61007b31 SH |
6753 | if (!bs || !bs->drv || !backing_file) { |
6754 | return NULL; | |
f9f05dc5 KW |
6755 | } |
6756 | ||
61007b31 SH |
6757 | filename_full = g_malloc(PATH_MAX); |
6758 | backing_file_full = g_malloc(PATH_MAX); | |
f9f05dc5 | 6759 | |
61007b31 | 6760 | is_protocol = path_has_protocol(backing_file); |
f9f05dc5 | 6761 | |
dcf3f9b2 HR |
6762 | /* |
6763 | * Being largely a legacy function, skip any filters here | |
6764 | * (because filters do not have normal filenames, so they cannot | |
6765 | * match anyway; and allowing json:{} filenames is a bit out of | |
6766 | * scope). | |
6767 | */ | |
6768 | for (curr_bs = bdrv_skip_filters(bs); | |
6769 | bdrv_cow_child(curr_bs) != NULL; | |
6770 | curr_bs = bs_below) | |
6771 | { | |
6772 | bs_below = bdrv_backing_chain_next(curr_bs); | |
f9f05dc5 | 6773 | |
0b877d09 HR |
6774 | if (bdrv_backing_overridden(curr_bs)) { |
6775 | /* | |
6776 | * If the backing file was overridden, we can only compare | |
6777 | * directly against the backing node's filename. | |
6778 | */ | |
6779 | ||
6780 | if (!filenames_refreshed) { | |
6781 | /* | |
6782 | * This will automatically refresh all of the | |
6783 | * filenames in the rest of the backing chain, so we | |
6784 | * only need to do this once. | |
6785 | */ | |
6786 | bdrv_refresh_filename(bs_below); | |
6787 | filenames_refreshed = true; | |
6788 | } | |
6789 | ||
6790 | if (strcmp(backing_file, bs_below->filename) == 0) { | |
6791 | retval = bs_below; | |
6792 | break; | |
6793 | } | |
6794 | } else if (is_protocol || path_has_protocol(curr_bs->backing_file)) { | |
6795 | /* | |
6796 | * If either of the filename paths is actually a protocol, then | |
6797 | * compare unmodified paths; otherwise make paths relative. | |
6798 | */ | |
6b6833c1 HR |
6799 | char *backing_file_full_ret; |
6800 | ||
61007b31 | 6801 | if (strcmp(backing_file, curr_bs->backing_file) == 0) { |
dcf3f9b2 | 6802 | retval = bs_below; |
61007b31 SH |
6803 | break; |
6804 | } | |
418661e0 | 6805 | /* Also check against the full backing filename for the image */ |
6b6833c1 HR |
6806 | backing_file_full_ret = bdrv_get_full_backing_filename(curr_bs, |
6807 | NULL); | |
6808 | if (backing_file_full_ret) { | |
6809 | bool equal = strcmp(backing_file, backing_file_full_ret) == 0; | |
6810 | g_free(backing_file_full_ret); | |
6811 | if (equal) { | |
dcf3f9b2 | 6812 | retval = bs_below; |
418661e0 JC |
6813 | break; |
6814 | } | |
418661e0 | 6815 | } |
61007b31 SH |
6816 | } else { |
6817 | /* If not an absolute filename path, make it relative to the current | |
6818 | * image's filename path */ | |
2d9158ce HR |
6819 | filename_tmp = bdrv_make_absolute_filename(curr_bs, backing_file, |
6820 | NULL); | |
6821 | /* We are going to compare canonicalized absolute pathnames */ | |
6822 | if (!filename_tmp || !realpath(filename_tmp, filename_full)) { | |
6823 | g_free(filename_tmp); | |
61007b31 SH |
6824 | continue; |
6825 | } | |
2d9158ce | 6826 | g_free(filename_tmp); |
07f07615 | 6827 | |
61007b31 SH |
6828 | /* We need to make sure the backing filename we are comparing against |
6829 | * is relative to the current image filename (or absolute) */ | |
2d9158ce HR |
6830 | filename_tmp = bdrv_get_full_backing_filename(curr_bs, NULL); |
6831 | if (!filename_tmp || !realpath(filename_tmp, backing_file_full)) { | |
6832 | g_free(filename_tmp); | |
61007b31 SH |
6833 | continue; |
6834 | } | |
2d9158ce | 6835 | g_free(filename_tmp); |
eb489bb1 | 6836 | |
61007b31 | 6837 | if (strcmp(backing_file_full, filename_full) == 0) { |
dcf3f9b2 | 6838 | retval = bs_below; |
61007b31 SH |
6839 | break; |
6840 | } | |
6841 | } | |
eb489bb1 KW |
6842 | } |
6843 | ||
61007b31 SH |
6844 | g_free(filename_full); |
6845 | g_free(backing_file_full); | |
61007b31 SH |
6846 | return retval; |
6847 | } | |
6848 | ||
61007b31 SH |
6849 | void bdrv_init(void) |
6850 | { | |
e5f05f8c KW |
6851 | #ifdef CONFIG_BDRV_WHITELIST_TOOLS |
6852 | use_bdrv_whitelist = 1; | |
6853 | #endif | |
61007b31 SH |
6854 | module_call_init(MODULE_INIT_BLOCK); |
6855 | } | |
29cdb251 | 6856 | |
61007b31 SH |
6857 | void bdrv_init_with_whitelist(void) |
6858 | { | |
6859 | use_bdrv_whitelist = 1; | |
6860 | bdrv_init(); | |
07f07615 PB |
6861 | } |
6862 | ||
a94750d9 | 6863 | int bdrv_activate(BlockDriverState *bs, Error **errp) |
0f15423c | 6864 | { |
4417ab7a | 6865 | BdrvChild *child, *parent; |
5a8a30db KW |
6866 | Error *local_err = NULL; |
6867 | int ret; | |
9c98f145 | 6868 | BdrvDirtyBitmap *bm; |
5a8a30db | 6869 | |
f791bf7f | 6870 | GLOBAL_STATE_CODE(); |
3804e3cf | 6871 | GRAPH_RDLOCK_GUARD_MAINLOOP(); |
f791bf7f | 6872 | |
3456a8d1 | 6873 | if (!bs->drv) { |
5416645f | 6874 | return -ENOMEDIUM; |
3456a8d1 KW |
6875 | } |
6876 | ||
16e977d5 | 6877 | QLIST_FOREACH(child, &bs->children, next) { |
11d0c9b3 | 6878 | bdrv_activate(child->bs, &local_err); |
0d1c5c91 | 6879 | if (local_err) { |
0d1c5c91 | 6880 | error_propagate(errp, local_err); |
5416645f | 6881 | return -EINVAL; |
0d1c5c91 | 6882 | } |
5a8a30db | 6883 | } |
0d1c5c91 | 6884 | |
dafe0960 KW |
6885 | /* |
6886 | * Update permissions, they may differ for inactive nodes. | |
6887 | * | |
6888 | * Note that the required permissions of inactive images are always a | |
6889 | * subset of the permissions required after activating the image. This | |
6890 | * allows us to just get the permissions upfront without restricting | |
11d0c9b3 | 6891 | * bdrv_co_invalidate_cache(). |
dafe0960 KW |
6892 | * |
6893 | * It also means that in error cases, we don't have to try and revert to | |
6894 | * the old permissions (which is an operation that could fail, too). We can | |
6895 | * just keep the extended permissions for the next time that an activation | |
6896 | * of the image is tried. | |
6897 | */ | |
7bb4941a KW |
6898 | if (bs->open_flags & BDRV_O_INACTIVE) { |
6899 | bs->open_flags &= ~BDRV_O_INACTIVE; | |
f1316edb | 6900 | ret = bdrv_refresh_perms(bs, NULL, errp); |
7bb4941a | 6901 | if (ret < 0) { |
0d1c5c91 | 6902 | bs->open_flags |= BDRV_O_INACTIVE; |
5416645f | 6903 | return ret; |
0d1c5c91 | 6904 | } |
3456a8d1 | 6905 | |
11d0c9b3 EGE |
6906 | ret = bdrv_invalidate_cache(bs, errp); |
6907 | if (ret < 0) { | |
6908 | bs->open_flags |= BDRV_O_INACTIVE; | |
6909 | return ret; | |
7bb4941a | 6910 | } |
9c98f145 | 6911 | |
7bb4941a KW |
6912 | FOR_EACH_DIRTY_BITMAP(bs, bm) { |
6913 | bdrv_dirty_bitmap_skip_store(bm, false); | |
6914 | } | |
6915 | ||
c057960c | 6916 | ret = bdrv_refresh_total_sectors(bs, bs->total_sectors); |
7bb4941a KW |
6917 | if (ret < 0) { |
6918 | bs->open_flags |= BDRV_O_INACTIVE; | |
6919 | error_setg_errno(errp, -ret, "Could not refresh total sector count"); | |
5416645f | 6920 | return ret; |
7bb4941a | 6921 | } |
5a8a30db | 6922 | } |
4417ab7a KW |
6923 | |
6924 | QLIST_FOREACH(parent, &bs->parents, next_parent) { | |
bd86fb99 HR |
6925 | if (parent->klass->activate) { |
6926 | parent->klass->activate(parent, &local_err); | |
4417ab7a | 6927 | if (local_err) { |
78fc3b3a | 6928 | bs->open_flags |= BDRV_O_INACTIVE; |
4417ab7a | 6929 | error_propagate(errp, local_err); |
5416645f | 6930 | return -EINVAL; |
4417ab7a KW |
6931 | } |
6932 | } | |
6933 | } | |
5416645f VSO |
6934 | |
6935 | return 0; | |
0f15423c AL |
6936 | } |
6937 | ||
11d0c9b3 EGE |
6938 | int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp) |
6939 | { | |
6940 | Error *local_err = NULL; | |
1581a70d | 6941 | IO_CODE(); |
11d0c9b3 EGE |
6942 | |
6943 | assert(!(bs->open_flags & BDRV_O_INACTIVE)); | |
1b3ff9fe | 6944 | assert_bdrv_graph_readable(); |
11d0c9b3 EGE |
6945 | |
6946 | if (bs->drv->bdrv_co_invalidate_cache) { | |
6947 | bs->drv->bdrv_co_invalidate_cache(bs, &local_err); | |
6948 | if (local_err) { | |
6949 | error_propagate(errp, local_err); | |
6950 | return -EINVAL; | |
6951 | } | |
6952 | } | |
6953 | ||
6954 | return 0; | |
6955 | } | |
6956 | ||
3b717194 | 6957 | void bdrv_activate_all(Error **errp) |
0f15423c | 6958 | { |
7c8eece4 | 6959 | BlockDriverState *bs; |
88be7b4b | 6960 | BdrvNextIterator it; |
0f15423c | 6961 | |
f791bf7f EGE |
6962 | GLOBAL_STATE_CODE(); |
6963 | ||
88be7b4b | 6964 | for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { |
ed78cda3 | 6965 | AioContext *aio_context = bdrv_get_aio_context(bs); |
5416645f | 6966 | int ret; |
ed78cda3 SH |
6967 | |
6968 | aio_context_acquire(aio_context); | |
a94750d9 | 6969 | ret = bdrv_activate(bs, errp); |
ed78cda3 | 6970 | aio_context_release(aio_context); |
5416645f | 6971 | if (ret < 0) { |
5e003f17 | 6972 | bdrv_next_cleanup(&it); |
5a8a30db KW |
6973 | return; |
6974 | } | |
0f15423c AL |
6975 | } |
6976 | } | |
6977 | ||
9e37271f KW |
6978 | static bool bdrv_has_bds_parent(BlockDriverState *bs, bool only_active) |
6979 | { | |
6980 | BdrvChild *parent; | |
bdb73476 | 6981 | GLOBAL_STATE_CODE(); |
9e37271f KW |
6982 | |
6983 | QLIST_FOREACH(parent, &bs->parents, next_parent) { | |
bd86fb99 | 6984 | if (parent->klass->parent_is_bds) { |
9e37271f KW |
6985 | BlockDriverState *parent_bs = parent->opaque; |
6986 | if (!only_active || !(parent_bs->open_flags & BDRV_O_INACTIVE)) { | |
6987 | return true; | |
6988 | } | |
6989 | } | |
6990 | } | |
6991 | ||
6992 | return false; | |
6993 | } | |
6994 | ||
6995 | static int bdrv_inactivate_recurse(BlockDriverState *bs) | |
76b1c7fe | 6996 | { |
cfa1a572 | 6997 | BdrvChild *child, *parent; |
76b1c7fe | 6998 | int ret; |
a13de40a | 6999 | uint64_t cumulative_perms, cumulative_shared_perms; |
76b1c7fe | 7000 | |
da359909 | 7001 | GLOBAL_STATE_CODE(); |
3804e3cf | 7002 | GRAPH_RDLOCK_GUARD_MAINLOOP(); |
da359909 | 7003 | |
d470ad42 HR |
7004 | if (!bs->drv) { |
7005 | return -ENOMEDIUM; | |
7006 | } | |
7007 | ||
9e37271f KW |
7008 | /* Make sure that we don't inactivate a child before its parent. |
7009 | * It will be covered by recursion from the yet active parent. */ | |
7010 | if (bdrv_has_bds_parent(bs, true)) { | |
7011 | return 0; | |
7012 | } | |
7013 | ||
7014 | assert(!(bs->open_flags & BDRV_O_INACTIVE)); | |
7015 | ||
7016 | /* Inactivate this node */ | |
7017 | if (bs->drv->bdrv_inactivate) { | |
76b1c7fe KW |
7018 | ret = bs->drv->bdrv_inactivate(bs); |
7019 | if (ret < 0) { | |
7020 | return ret; | |
7021 | } | |
7022 | } | |
7023 | ||
9e37271f | 7024 | QLIST_FOREACH(parent, &bs->parents, next_parent) { |
bd86fb99 HR |
7025 | if (parent->klass->inactivate) { |
7026 | ret = parent->klass->inactivate(parent); | |
9e37271f KW |
7027 | if (ret < 0) { |
7028 | return ret; | |
cfa1a572 KW |
7029 | } |
7030 | } | |
9e37271f | 7031 | } |
9c5e6594 | 7032 | |
a13de40a VSO |
7033 | bdrv_get_cumulative_perm(bs, &cumulative_perms, |
7034 | &cumulative_shared_perms); | |
7035 | if (cumulative_perms & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) { | |
7036 | /* Our inactive parents still need write access. Inactivation failed. */ | |
7037 | return -EPERM; | |
7038 | } | |
7039 | ||
9e37271f | 7040 | bs->open_flags |= BDRV_O_INACTIVE; |
7d5b5261 | 7041 | |
bb87e4d1 VSO |
7042 | /* |
7043 | * Update permissions, they may differ for inactive nodes. | |
7044 | * We only tried to loosen restrictions, so errors are not fatal, ignore | |
7045 | * them. | |
7046 | */ | |
f1316edb | 7047 | bdrv_refresh_perms(bs, NULL, NULL); |
9e37271f KW |
7048 | |
7049 | /* Recursively inactivate children */ | |
38701b6a | 7050 | QLIST_FOREACH(child, &bs->children, next) { |
9e37271f | 7051 | ret = bdrv_inactivate_recurse(child->bs); |
38701b6a KW |
7052 | if (ret < 0) { |
7053 | return ret; | |
7054 | } | |
7055 | } | |
7056 | ||
76b1c7fe KW |
7057 | return 0; |
7058 | } | |
7059 | ||
7060 | int bdrv_inactivate_all(void) | |
7061 | { | |
79720af6 | 7062 | BlockDriverState *bs = NULL; |
88be7b4b | 7063 | BdrvNextIterator it; |
aad0b7a0 | 7064 | int ret = 0; |
bd6458e4 | 7065 | GSList *aio_ctxs = NULL, *ctx; |
76b1c7fe | 7066 | |
f791bf7f EGE |
7067 | GLOBAL_STATE_CODE(); |
7068 | ||
88be7b4b | 7069 | for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { |
bd6458e4 PB |
7070 | AioContext *aio_context = bdrv_get_aio_context(bs); |
7071 | ||
7072 | if (!g_slist_find(aio_ctxs, aio_context)) { | |
7073 | aio_ctxs = g_slist_prepend(aio_ctxs, aio_context); | |
7074 | aio_context_acquire(aio_context); | |
7075 | } | |
aad0b7a0 | 7076 | } |
76b1c7fe | 7077 | |
9e37271f KW |
7078 | for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { |
7079 | /* Nodes with BDS parents are covered by recursion from the last | |
7080 | * parent that gets inactivated. Don't inactivate them a second | |
7081 | * time if that has already happened. */ | |
7082 | if (bdrv_has_bds_parent(bs, false)) { | |
7083 | continue; | |
7084 | } | |
7085 | ret = bdrv_inactivate_recurse(bs); | |
7086 | if (ret < 0) { | |
7087 | bdrv_next_cleanup(&it); | |
7088 | goto out; | |
76b1c7fe KW |
7089 | } |
7090 | } | |
7091 | ||
aad0b7a0 | 7092 | out: |
bd6458e4 PB |
7093 | for (ctx = aio_ctxs; ctx != NULL; ctx = ctx->next) { |
7094 | AioContext *aio_context = ctx->data; | |
7095 | aio_context_release(aio_context); | |
aad0b7a0 | 7096 | } |
bd6458e4 | 7097 | g_slist_free(aio_ctxs); |
aad0b7a0 FZ |
7098 | |
7099 | return ret; | |
76b1c7fe KW |
7100 | } |
7101 | ||
19cb3738 FB |
7102 | /**************************************************************/ |
7103 | /* removable device support */ | |
7104 | ||
7105 | /** | |
7106 | * Return TRUE if the media is present | |
7107 | */ | |
1e97be91 | 7108 | bool coroutine_fn bdrv_co_is_inserted(BlockDriverState *bs) |
19cb3738 FB |
7109 | { |
7110 | BlockDriver *drv = bs->drv; | |
28d7a789 | 7111 | BdrvChild *child; |
384a48fb | 7112 | IO_CODE(); |
c73ff92c | 7113 | assert_bdrv_graph_readable(); |
a1aff5bf | 7114 | |
e031f750 HR |
7115 | if (!drv) { |
7116 | return false; | |
7117 | } | |
1e97be91 EGE |
7118 | if (drv->bdrv_co_is_inserted) { |
7119 | return drv->bdrv_co_is_inserted(bs); | |
28d7a789 HR |
7120 | } |
7121 | QLIST_FOREACH(child, &bs->children, next) { | |
1e97be91 | 7122 | if (!bdrv_co_is_inserted(child->bs)) { |
28d7a789 HR |
7123 | return false; |
7124 | } | |
e031f750 | 7125 | } |
28d7a789 | 7126 | return true; |
19cb3738 FB |
7127 | } |
7128 | ||
19cb3738 FB |
7129 | /** |
7130 | * If eject_flag is TRUE, eject the media. Otherwise, close the tray | |
7131 | */ | |
2531b390 | 7132 | void coroutine_fn bdrv_co_eject(BlockDriverState *bs, bool eject_flag) |
19cb3738 FB |
7133 | { |
7134 | BlockDriver *drv = bs->drv; | |
384a48fb | 7135 | IO_CODE(); |
79a292e5 | 7136 | assert_bdrv_graph_readable(); |
19cb3738 | 7137 | |
2531b390 EGE |
7138 | if (drv && drv->bdrv_co_eject) { |
7139 | drv->bdrv_co_eject(bs, eject_flag); | |
19cb3738 FB |
7140 | } |
7141 | } | |
7142 | ||
19cb3738 FB |
7143 | /** |
7144 | * Lock or unlock the media (if it is locked, the user won't be able | |
7145 | * to eject it manually). | |
7146 | */ | |
2c75261c | 7147 | void coroutine_fn bdrv_co_lock_medium(BlockDriverState *bs, bool locked) |
19cb3738 FB |
7148 | { |
7149 | BlockDriver *drv = bs->drv; | |
384a48fb | 7150 | IO_CODE(); |
79a292e5 | 7151 | assert_bdrv_graph_readable(); |
025e849a | 7152 | trace_bdrv_lock_medium(bs, locked); |
b8c6d095 | 7153 | |
2c75261c EGE |
7154 | if (drv && drv->bdrv_co_lock_medium) { |
7155 | drv->bdrv_co_lock_medium(bs, locked); | |
19cb3738 FB |
7156 | } |
7157 | } | |
985a03b0 | 7158 | |
9fcb0251 FZ |
7159 | /* Get a reference to bs */ |
7160 | void bdrv_ref(BlockDriverState *bs) | |
7161 | { | |
f791bf7f | 7162 | GLOBAL_STATE_CODE(); |
9fcb0251 FZ |
7163 | bs->refcnt++; |
7164 | } | |
7165 | ||
7166 | /* Release a previously grabbed reference to bs. | |
7167 | * If after releasing, reference count is zero, the BlockDriverState is | |
7168 | * deleted. */ | |
7169 | void bdrv_unref(BlockDriverState *bs) | |
7170 | { | |
f791bf7f | 7171 | GLOBAL_STATE_CODE(); |
9a4d5ca6 JC |
7172 | if (!bs) { |
7173 | return; | |
7174 | } | |
9fcb0251 FZ |
7175 | assert(bs->refcnt > 0); |
7176 | if (--bs->refcnt == 0) { | |
7177 | bdrv_delete(bs); | |
7178 | } | |
7179 | } | |
7180 | ||
ac2ae233 KW |
7181 | /* |
7182 | * Release a BlockDriverState reference while holding the graph write lock. | |
7183 | * | |
7184 | * Calling bdrv_unref() directly is forbidden while holding the graph lock | |
7185 | * because bdrv_close() both involves polling and taking the graph lock | |
7186 | * internally. bdrv_schedule_unref() instead delays decreasing the refcount and | |
7187 | * possibly closing @bs until the graph lock is released. | |
7188 | */ | |
7189 | void bdrv_schedule_unref(BlockDriverState *bs) | |
7190 | { | |
7191 | if (!bs) { | |
7192 | return; | |
7193 | } | |
7194 | aio_bh_schedule_oneshot(qemu_get_aio_context(), | |
7195 | (QEMUBHFunc *) bdrv_unref, bs); | |
7196 | } | |
7197 | ||
fbe40ff7 FZ |
7198 | struct BdrvOpBlocker { |
7199 | Error *reason; | |
7200 | QLIST_ENTRY(BdrvOpBlocker) list; | |
7201 | }; | |
7202 | ||
7203 | bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp) | |
7204 | { | |
7205 | BdrvOpBlocker *blocker; | |
f791bf7f | 7206 | GLOBAL_STATE_CODE(); |
fbe40ff7 FZ |
7207 | assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); |
7208 | if (!QLIST_EMPTY(&bs->op_blockers[op])) { | |
7209 | blocker = QLIST_FIRST(&bs->op_blockers[op]); | |
4b576648 MA |
7210 | error_propagate_prepend(errp, error_copy(blocker->reason), |
7211 | "Node '%s' is busy: ", | |
7212 | bdrv_get_device_or_node_name(bs)); | |
fbe40ff7 FZ |
7213 | return true; |
7214 | } | |
7215 | return false; | |
7216 | } | |
7217 | ||
7218 | void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason) | |
7219 | { | |
7220 | BdrvOpBlocker *blocker; | |
f791bf7f | 7221 | GLOBAL_STATE_CODE(); |
fbe40ff7 FZ |
7222 | assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); |
7223 | ||
5839e53b | 7224 | blocker = g_new0(BdrvOpBlocker, 1); |
fbe40ff7 FZ |
7225 | blocker->reason = reason; |
7226 | QLIST_INSERT_HEAD(&bs->op_blockers[op], blocker, list); | |
7227 | } | |
7228 | ||
7229 | void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason) | |
7230 | { | |
7231 | BdrvOpBlocker *blocker, *next; | |
f791bf7f | 7232 | GLOBAL_STATE_CODE(); |
fbe40ff7 FZ |
7233 | assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); |
7234 | QLIST_FOREACH_SAFE(blocker, &bs->op_blockers[op], list, next) { | |
7235 | if (blocker->reason == reason) { | |
7236 | QLIST_REMOVE(blocker, list); | |
7237 | g_free(blocker); | |
7238 | } | |
7239 | } | |
7240 | } | |
7241 | ||
7242 | void bdrv_op_block_all(BlockDriverState *bs, Error *reason) | |
7243 | { | |
7244 | int i; | |
f791bf7f | 7245 | GLOBAL_STATE_CODE(); |
fbe40ff7 FZ |
7246 | for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { |
7247 | bdrv_op_block(bs, i, reason); | |
7248 | } | |
7249 | } | |
7250 | ||
7251 | void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason) | |
7252 | { | |
7253 | int i; | |
f791bf7f | 7254 | GLOBAL_STATE_CODE(); |
fbe40ff7 FZ |
7255 | for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { |
7256 | bdrv_op_unblock(bs, i, reason); | |
7257 | } | |
7258 | } | |
7259 | ||
7260 | bool bdrv_op_blocker_is_empty(BlockDriverState *bs) | |
7261 | { | |
7262 | int i; | |
f791bf7f | 7263 | GLOBAL_STATE_CODE(); |
fbe40ff7 FZ |
7264 | for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { |
7265 | if (!QLIST_EMPTY(&bs->op_blockers[i])) { | |
7266 | return false; | |
7267 | } | |
7268 | } | |
7269 | return true; | |
7270 | } | |
7271 | ||
e1355055 KW |
7272 | /* |
7273 | * Must not be called while holding the lock of an AioContext other than the | |
7274 | * current one. | |
7275 | */ | |
d92ada22 LC |
7276 | void bdrv_img_create(const char *filename, const char *fmt, |
7277 | const char *base_filename, const char *base_fmt, | |
9217283d FZ |
7278 | char *options, uint64_t img_size, int flags, bool quiet, |
7279 | Error **errp) | |
f88e1a42 | 7280 | { |
83d0521a CL |
7281 | QemuOptsList *create_opts = NULL; |
7282 | QemuOpts *opts = NULL; | |
7283 | const char *backing_fmt, *backing_file; | |
7284 | int64_t size; | |
f88e1a42 | 7285 | BlockDriver *drv, *proto_drv; |
cc84d90f | 7286 | Error *local_err = NULL; |
f88e1a42 JS |
7287 | int ret = 0; |
7288 | ||
f791bf7f EGE |
7289 | GLOBAL_STATE_CODE(); |
7290 | ||
f88e1a42 JS |
7291 | /* Find driver and parse its options */ |
7292 | drv = bdrv_find_format(fmt); | |
7293 | if (!drv) { | |
71c79813 | 7294 | error_setg(errp, "Unknown file format '%s'", fmt); |
d92ada22 | 7295 | return; |
f88e1a42 JS |
7296 | } |
7297 | ||
b65a5e12 | 7298 | proto_drv = bdrv_find_protocol(filename, true, errp); |
f88e1a42 | 7299 | if (!proto_drv) { |
d92ada22 | 7300 | return; |
f88e1a42 JS |
7301 | } |
7302 | ||
c6149724 HR |
7303 | if (!drv->create_opts) { |
7304 | error_setg(errp, "Format driver '%s' does not support image creation", | |
7305 | drv->format_name); | |
7306 | return; | |
7307 | } | |
7308 | ||
5a5e7f8c ML |
7309 | if (!proto_drv->create_opts) { |
7310 | error_setg(errp, "Protocol driver '%s' does not support image creation", | |
7311 | proto_drv->format_name); | |
7312 | return; | |
7313 | } | |
7314 | ||
c6e0a6de KW |
7315 | aio_context_acquire(qemu_get_aio_context()); |
7316 | ||
f6dc1c31 | 7317 | /* Create parameter list */ |
c282e1fd | 7318 | create_opts = qemu_opts_append(create_opts, drv->create_opts); |
5a5e7f8c | 7319 | create_opts = qemu_opts_append(create_opts, proto_drv->create_opts); |
f88e1a42 | 7320 | |
83d0521a | 7321 | opts = qemu_opts_create(create_opts, NULL, 0, &error_abort); |
f88e1a42 JS |
7322 | |
7323 | /* Parse -o options */ | |
7324 | if (options) { | |
a5f9b9df | 7325 | if (!qemu_opts_do_parse(opts, options, NULL, errp)) { |
f88e1a42 JS |
7326 | goto out; |
7327 | } | |
7328 | } | |
7329 | ||
f6dc1c31 KW |
7330 | if (!qemu_opt_get(opts, BLOCK_OPT_SIZE)) { |
7331 | qemu_opt_set_number(opts, BLOCK_OPT_SIZE, img_size, &error_abort); | |
7332 | } else if (img_size != UINT64_C(-1)) { | |
7333 | error_setg(errp, "The image size must be specified only once"); | |
7334 | goto out; | |
7335 | } | |
7336 | ||
f88e1a42 | 7337 | if (base_filename) { |
235e59cf | 7338 | if (!qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, base_filename, |
3882578b | 7339 | NULL)) { |
71c79813 LC |
7340 | error_setg(errp, "Backing file not supported for file format '%s'", |
7341 | fmt); | |
f88e1a42 JS |
7342 | goto out; |
7343 | } | |
7344 | } | |
7345 | ||
7346 | if (base_fmt) { | |
3882578b | 7347 | if (!qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, base_fmt, NULL)) { |
71c79813 LC |
7348 | error_setg(errp, "Backing file format not supported for file " |
7349 | "format '%s'", fmt); | |
f88e1a42 JS |
7350 | goto out; |
7351 | } | |
7352 | } | |
7353 | ||
83d0521a CL |
7354 | backing_file = qemu_opt_get(opts, BLOCK_OPT_BACKING_FILE); |
7355 | if (backing_file) { | |
7356 | if (!strcmp(filename, backing_file)) { | |
71c79813 LC |
7357 | error_setg(errp, "Error: Trying to create an image with the " |
7358 | "same filename as the backing file"); | |
792da93a JS |
7359 | goto out; |
7360 | } | |
975a7bd2 CK |
7361 | if (backing_file[0] == '\0') { |
7362 | error_setg(errp, "Expected backing file name, got empty string"); | |
7363 | goto out; | |
7364 | } | |
792da93a JS |
7365 | } |
7366 | ||
83d0521a | 7367 | backing_fmt = qemu_opt_get(opts, BLOCK_OPT_BACKING_FMT); |
f88e1a42 | 7368 | |
6e6e55f5 JS |
7369 | /* The size for the image must always be specified, unless we have a backing |
7370 | * file and we have not been forbidden from opening it. */ | |
a8b42a1c | 7371 | size = qemu_opt_get_size(opts, BLOCK_OPT_SIZE, img_size); |
6e6e55f5 JS |
7372 | if (backing_file && !(flags & BDRV_O_NO_BACKING)) { |
7373 | BlockDriverState *bs; | |
645ae7d8 | 7374 | char *full_backing; |
6e6e55f5 JS |
7375 | int back_flags; |
7376 | QDict *backing_options = NULL; | |
7377 | ||
645ae7d8 HR |
7378 | full_backing = |
7379 | bdrv_get_full_backing_filename_from_filename(filename, backing_file, | |
7380 | &local_err); | |
6e6e55f5 | 7381 | if (local_err) { |
6e6e55f5 JS |
7382 | goto out; |
7383 | } | |
645ae7d8 | 7384 | assert(full_backing); |
29168018 | 7385 | |
d5b23994 HR |
7386 | /* |
7387 | * No need to do I/O here, which allows us to open encrypted | |
7388 | * backing images without needing the secret | |
7389 | */ | |
6e6e55f5 JS |
7390 | back_flags = flags; |
7391 | back_flags &= ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); | |
d5b23994 | 7392 | back_flags |= BDRV_O_NO_IO; |
f88e1a42 | 7393 | |
cc954f01 | 7394 | backing_options = qdict_new(); |
6e6e55f5 | 7395 | if (backing_fmt) { |
6e6e55f5 JS |
7396 | qdict_put_str(backing_options, "driver", backing_fmt); |
7397 | } | |
cc954f01 | 7398 | qdict_put_bool(backing_options, BDRV_OPT_FORCE_SHARE, true); |
e6641719 | 7399 | |
6e6e55f5 JS |
7400 | bs = bdrv_open(full_backing, NULL, backing_options, back_flags, |
7401 | &local_err); | |
7402 | g_free(full_backing); | |
add8200d EB |
7403 | if (!bs) { |
7404 | error_append_hint(&local_err, "Could not open backing image.\n"); | |
6e6e55f5 JS |
7405 | goto out; |
7406 | } else { | |
d9f059aa | 7407 | if (!backing_fmt) { |
497a30db EB |
7408 | error_setg(&local_err, |
7409 | "Backing file specified without backing format"); | |
fbdffb08 | 7410 | error_append_hint(&local_err, "Detected format of %s.\n", |
497a30db EB |
7411 | bs->drv->format_name); |
7412 | goto out; | |
d9f059aa | 7413 | } |
6e6e55f5 JS |
7414 | if (size == -1) { |
7415 | /* Opened BS, have no size */ | |
7416 | size = bdrv_getlength(bs); | |
7417 | if (size < 0) { | |
7418 | error_setg_errno(errp, -size, "Could not get size of '%s'", | |
7419 | backing_file); | |
7420 | bdrv_unref(bs); | |
7421 | goto out; | |
7422 | } | |
7423 | qemu_opt_set_number(opts, BLOCK_OPT_SIZE, size, &error_abort); | |
52bf1e72 | 7424 | } |
66f6b814 | 7425 | bdrv_unref(bs); |
f88e1a42 | 7426 | } |
d9f059aa EB |
7427 | /* (backing_file && !(flags & BDRV_O_NO_BACKING)) */ |
7428 | } else if (backing_file && !backing_fmt) { | |
497a30db EB |
7429 | error_setg(&local_err, |
7430 | "Backing file specified without backing format"); | |
7431 | goto out; | |
d9f059aa | 7432 | } |
6e6e55f5 JS |
7433 | |
7434 | if (size == -1) { | |
7435 | error_setg(errp, "Image creation needs a size parameter"); | |
7436 | goto out; | |
f88e1a42 JS |
7437 | } |
7438 | ||
f382d43a | 7439 | if (!quiet) { |
fe646693 | 7440 | printf("Formatting '%s', fmt=%s ", filename, fmt); |
43c5d8f8 | 7441 | qemu_opts_print(opts, " "); |
f382d43a | 7442 | puts(""); |
4e2f4418 | 7443 | fflush(stdout); |
f382d43a | 7444 | } |
83d0521a | 7445 | |
c282e1fd | 7446 | ret = bdrv_create(drv, filename, opts, &local_err); |
83d0521a | 7447 | |
cc84d90f HR |
7448 | if (ret == -EFBIG) { |
7449 | /* This is generally a better message than whatever the driver would | |
7450 | * deliver (especially because of the cluster_size_hint), since that | |
7451 | * is most probably not much different from "image too large". */ | |
7452 | const char *cluster_size_hint = ""; | |
83d0521a | 7453 | if (qemu_opt_get_size(opts, BLOCK_OPT_CLUSTER_SIZE, 0)) { |
cc84d90f | 7454 | cluster_size_hint = " (try using a larger cluster size)"; |
f88e1a42 | 7455 | } |
cc84d90f HR |
7456 | error_setg(errp, "The image size is too large for file format '%s'" |
7457 | "%s", fmt, cluster_size_hint); | |
7458 | error_free(local_err); | |
7459 | local_err = NULL; | |
f88e1a42 JS |
7460 | } |
7461 | ||
7462 | out: | |
83d0521a CL |
7463 | qemu_opts_del(opts); |
7464 | qemu_opts_free(create_opts); | |
621ff94d | 7465 | error_propagate(errp, local_err); |
c6e0a6de | 7466 | aio_context_release(qemu_get_aio_context()); |
f88e1a42 | 7467 | } |
85d126f3 SH |
7468 | |
7469 | AioContext *bdrv_get_aio_context(BlockDriverState *bs) | |
7470 | { | |
384a48fb | 7471 | IO_CODE(); |
33f2a757 | 7472 | return bs ? bs->aio_context : qemu_get_aio_context(); |
dcd04228 SH |
7473 | } |
7474 | ||
e336fd4c KW |
7475 | AioContext *coroutine_fn bdrv_co_enter(BlockDriverState *bs) |
7476 | { | |
7477 | Coroutine *self = qemu_coroutine_self(); | |
7478 | AioContext *old_ctx = qemu_coroutine_get_aio_context(self); | |
7479 | AioContext *new_ctx; | |
384a48fb | 7480 | IO_CODE(); |
e336fd4c KW |
7481 | |
7482 | /* | |
7483 | * Increase bs->in_flight to ensure that this operation is completed before | |
7484 | * moving the node to a different AioContext. Read new_ctx only afterwards. | |
7485 | */ | |
7486 | bdrv_inc_in_flight(bs); | |
7487 | ||
7488 | new_ctx = bdrv_get_aio_context(bs); | |
7489 | aio_co_reschedule_self(new_ctx); | |
7490 | return old_ctx; | |
7491 | } | |
7492 | ||
7493 | void coroutine_fn bdrv_co_leave(BlockDriverState *bs, AioContext *old_ctx) | |
7494 | { | |
384a48fb | 7495 | IO_CODE(); |
e336fd4c KW |
7496 | aio_co_reschedule_self(old_ctx); |
7497 | bdrv_dec_in_flight(bs); | |
7498 | } | |
7499 | ||
18c6ac1c KW |
7500 | void coroutine_fn bdrv_co_lock(BlockDriverState *bs) |
7501 | { | |
7502 | AioContext *ctx = bdrv_get_aio_context(bs); | |
7503 | ||
7504 | /* In the main thread, bs->aio_context won't change concurrently */ | |
7505 | assert(qemu_get_current_aio_context() == qemu_get_aio_context()); | |
7506 | ||
7507 | /* | |
7508 | * We're in coroutine context, so we already hold the lock of the main | |
7509 | * loop AioContext. Don't lock it twice to avoid deadlocks. | |
7510 | */ | |
7511 | assert(qemu_in_coroutine()); | |
7512 | if (ctx != qemu_get_aio_context()) { | |
7513 | aio_context_acquire(ctx); | |
7514 | } | |
7515 | } | |
7516 | ||
7517 | void coroutine_fn bdrv_co_unlock(BlockDriverState *bs) | |
7518 | { | |
7519 | AioContext *ctx = bdrv_get_aio_context(bs); | |
7520 | ||
7521 | assert(qemu_in_coroutine()); | |
7522 | if (ctx != qemu_get_aio_context()) { | |
7523 | aio_context_release(ctx); | |
7524 | } | |
7525 | } | |
7526 | ||
e8a095da SH |
7527 | static void bdrv_do_remove_aio_context_notifier(BdrvAioNotifier *ban) |
7528 | { | |
bdb73476 | 7529 | GLOBAL_STATE_CODE(); |
e8a095da SH |
7530 | QLIST_REMOVE(ban, list); |
7531 | g_free(ban); | |
7532 | } | |
7533 | ||
a3a683c3 | 7534 | static void bdrv_detach_aio_context(BlockDriverState *bs) |
dcd04228 | 7535 | { |
e8a095da | 7536 | BdrvAioNotifier *baf, *baf_tmp; |
33384421 | 7537 | |
e8a095da | 7538 | assert(!bs->walking_aio_notifiers); |
da359909 | 7539 | GLOBAL_STATE_CODE(); |
e8a095da SH |
7540 | bs->walking_aio_notifiers = true; |
7541 | QLIST_FOREACH_SAFE(baf, &bs->aio_notifiers, list, baf_tmp) { | |
7542 | if (baf->deleted) { | |
7543 | bdrv_do_remove_aio_context_notifier(baf); | |
7544 | } else { | |
7545 | baf->detach_aio_context(baf->opaque); | |
7546 | } | |
33384421 | 7547 | } |
e8a095da SH |
7548 | /* Never mind iterating again to check for ->deleted. bdrv_close() will |
7549 | * remove remaining aio notifiers if we aren't called again. | |
7550 | */ | |
7551 | bs->walking_aio_notifiers = false; | |
33384421 | 7552 | |
1bffe1ae | 7553 | if (bs->drv && bs->drv->bdrv_detach_aio_context) { |
dcd04228 SH |
7554 | bs->drv->bdrv_detach_aio_context(bs); |
7555 | } | |
dcd04228 SH |
7556 | |
7557 | bs->aio_context = NULL; | |
7558 | } | |
7559 | ||
a3a683c3 KW |
7560 | static void bdrv_attach_aio_context(BlockDriverState *bs, |
7561 | AioContext *new_context) | |
dcd04228 | 7562 | { |
e8a095da | 7563 | BdrvAioNotifier *ban, *ban_tmp; |
da359909 | 7564 | GLOBAL_STATE_CODE(); |
33384421 | 7565 | |
dcd04228 SH |
7566 | bs->aio_context = new_context; |
7567 | ||
1bffe1ae | 7568 | if (bs->drv && bs->drv->bdrv_attach_aio_context) { |
dcd04228 SH |
7569 | bs->drv->bdrv_attach_aio_context(bs, new_context); |
7570 | } | |
33384421 | 7571 | |
e8a095da SH |
7572 | assert(!bs->walking_aio_notifiers); |
7573 | bs->walking_aio_notifiers = true; | |
7574 | QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_tmp) { | |
7575 | if (ban->deleted) { | |
7576 | bdrv_do_remove_aio_context_notifier(ban); | |
7577 | } else { | |
7578 | ban->attached_aio_context(new_context, ban->opaque); | |
7579 | } | |
33384421 | 7580 | } |
e8a095da | 7581 | bs->walking_aio_notifiers = false; |
dcd04228 SH |
7582 | } |
7583 | ||
7e8c182f EGE |
7584 | typedef struct BdrvStateSetAioContext { |
7585 | AioContext *new_ctx; | |
7586 | BlockDriverState *bs; | |
7587 | } BdrvStateSetAioContext; | |
d616b224 | 7588 | |
7e8c182f | 7589 | static bool bdrv_parent_change_aio_context(BdrvChild *c, AioContext *ctx, |
e08cc001 EGE |
7590 | GHashTable *visited, |
7591 | Transaction *tran, | |
7e8c182f | 7592 | Error **errp) |
5d231849 | 7593 | { |
f0c28327 | 7594 | GLOBAL_STATE_CODE(); |
e08cc001 | 7595 | if (g_hash_table_contains(visited, c)) { |
5d231849 KW |
7596 | return true; |
7597 | } | |
e08cc001 | 7598 | g_hash_table_add(visited, c); |
5d231849 | 7599 | |
bd86fb99 HR |
7600 | /* |
7601 | * A BdrvChildClass that doesn't handle AioContext changes cannot | |
7602 | * tolerate any AioContext changes | |
7603 | */ | |
7e8c182f | 7604 | if (!c->klass->change_aio_ctx) { |
5d231849 KW |
7605 | char *user = bdrv_child_user_desc(c); |
7606 | error_setg(errp, "Changing iothreads is not supported by %s", user); | |
7607 | g_free(user); | |
7608 | return false; | |
7609 | } | |
7e8c182f | 7610 | if (!c->klass->change_aio_ctx(c, ctx, visited, tran, errp)) { |
5d231849 KW |
7611 | assert(!errp || *errp); |
7612 | return false; | |
7613 | } | |
7614 | return true; | |
7615 | } | |
7616 | ||
7e8c182f | 7617 | bool bdrv_child_change_aio_context(BdrvChild *c, AioContext *ctx, |
e08cc001 | 7618 | GHashTable *visited, Transaction *tran, |
7e8c182f | 7619 | Error **errp) |
5d231849 | 7620 | { |
f791bf7f | 7621 | GLOBAL_STATE_CODE(); |
e08cc001 | 7622 | if (g_hash_table_contains(visited, c)) { |
5d231849 KW |
7623 | return true; |
7624 | } | |
e08cc001 | 7625 | g_hash_table_add(visited, c); |
7e8c182f | 7626 | return bdrv_change_aio_context(c->bs, ctx, visited, tran, errp); |
5d231849 KW |
7627 | } |
7628 | ||
7e8c182f EGE |
7629 | static void bdrv_set_aio_context_clean(void *opaque) |
7630 | { | |
7631 | BdrvStateSetAioContext *state = (BdrvStateSetAioContext *) opaque; | |
7632 | BlockDriverState *bs = (BlockDriverState *) state->bs; | |
7633 | ||
7634 | /* Paired with bdrv_drained_begin in bdrv_change_aio_context() */ | |
7635 | bdrv_drained_end(bs); | |
7636 | ||
7637 | g_free(state); | |
7638 | } | |
7639 | ||
7640 | static void bdrv_set_aio_context_commit(void *opaque) | |
7641 | { | |
7642 | BdrvStateSetAioContext *state = (BdrvStateSetAioContext *) opaque; | |
7643 | BlockDriverState *bs = (BlockDriverState *) state->bs; | |
7644 | AioContext *new_context = state->new_ctx; | |
7645 | AioContext *old_context = bdrv_get_aio_context(bs); | |
7e8c182f EGE |
7646 | |
7647 | /* | |
7648 | * Take the old AioContex when detaching it from bs. | |
7649 | * At this point, new_context lock is already acquired, and we are now | |
7650 | * also taking old_context. This is safe as long as bdrv_detach_aio_context | |
7651 | * does not call AIO_POLL_WHILE(). | |
7652 | */ | |
7653 | if (old_context != qemu_get_aio_context()) { | |
7654 | aio_context_acquire(old_context); | |
7655 | } | |
7656 | bdrv_detach_aio_context(bs); | |
7657 | if (old_context != qemu_get_aio_context()) { | |
7658 | aio_context_release(old_context); | |
7659 | } | |
7660 | bdrv_attach_aio_context(bs, new_context); | |
7661 | } | |
7662 | ||
7663 | static TransactionActionDrv set_aio_context = { | |
7664 | .commit = bdrv_set_aio_context_commit, | |
7665 | .clean = bdrv_set_aio_context_clean, | |
7666 | }; | |
7667 | ||
7668 | /* | |
7669 | * Changes the AioContext used for fd handlers, timers, and BHs by this | |
7670 | * BlockDriverState and all its children and parents. | |
7671 | * | |
7672 | * Must be called from the main AioContext. | |
7673 | * | |
7674 | * The caller must own the AioContext lock for the old AioContext of bs, but it | |
7675 | * must not own the AioContext lock for new_context (unless new_context is the | |
7676 | * same as the current context of bs). | |
7677 | * | |
7678 | * @visited will accumulate all visited BdrvChild objects. The caller is | |
7679 | * responsible for freeing the list afterwards. | |
7680 | */ | |
7681 | static bool bdrv_change_aio_context(BlockDriverState *bs, AioContext *ctx, | |
e08cc001 | 7682 | GHashTable *visited, Transaction *tran, |
7e8c182f | 7683 | Error **errp) |
5d231849 KW |
7684 | { |
7685 | BdrvChild *c; | |
7e8c182f EGE |
7686 | BdrvStateSetAioContext *state; |
7687 | ||
7688 | GLOBAL_STATE_CODE(); | |
5d231849 KW |
7689 | |
7690 | if (bdrv_get_aio_context(bs) == ctx) { | |
7691 | return true; | |
7692 | } | |
7693 | ||
7f831d29 | 7694 | bdrv_graph_rdlock_main_loop(); |
5d231849 | 7695 | QLIST_FOREACH(c, &bs->parents, next_parent) { |
7e8c182f | 7696 | if (!bdrv_parent_change_aio_context(c, ctx, visited, tran, errp)) { |
7f831d29 | 7697 | bdrv_graph_rdunlock_main_loop(); |
5d231849 KW |
7698 | return false; |
7699 | } | |
7700 | } | |
7e8c182f | 7701 | |
5d231849 | 7702 | QLIST_FOREACH(c, &bs->children, next) { |
7e8c182f | 7703 | if (!bdrv_child_change_aio_context(c, ctx, visited, tran, errp)) { |
7f831d29 | 7704 | bdrv_graph_rdunlock_main_loop(); |
5d231849 KW |
7705 | return false; |
7706 | } | |
7707 | } | |
7f831d29 | 7708 | bdrv_graph_rdunlock_main_loop(); |
5d231849 | 7709 | |
7e8c182f EGE |
7710 | state = g_new(BdrvStateSetAioContext, 1); |
7711 | *state = (BdrvStateSetAioContext) { | |
7712 | .new_ctx = ctx, | |
7713 | .bs = bs, | |
7714 | }; | |
7715 | ||
7716 | /* Paired with bdrv_drained_end in bdrv_set_aio_context_clean() */ | |
7717 | bdrv_drained_begin(bs); | |
7718 | ||
7719 | tran_add(tran, &set_aio_context, state); | |
7720 | ||
5d231849 KW |
7721 | return true; |
7722 | } | |
7723 | ||
7e8c182f EGE |
7724 | /* |
7725 | * Change bs's and recursively all of its parents' and children's AioContext | |
7726 | * to the given new context, returning an error if that isn't possible. | |
7727 | * | |
7728 | * If ignore_child is not NULL, that child (and its subgraph) will not | |
7729 | * be touched. | |
7730 | * | |
7731 | * This function still requires the caller to take the bs current | |
7732 | * AioContext lock, otherwise draining will fail since AIO_WAIT_WHILE | |
7733 | * assumes the lock is always held if bs is in another AioContext. | |
7734 | * For the same reason, it temporarily also holds the new AioContext, since | |
7735 | * bdrv_drained_end calls BDRV_POLL_WHILE that assumes the lock is taken too. | |
7736 | * Therefore the new AioContext lock must not be taken by the caller. | |
7737 | */ | |
a41cfda1 EGE |
7738 | int bdrv_try_change_aio_context(BlockDriverState *bs, AioContext *ctx, |
7739 | BdrvChild *ignore_child, Error **errp) | |
5d231849 | 7740 | { |
7e8c182f | 7741 | Transaction *tran; |
e08cc001 | 7742 | GHashTable *visited; |
7e8c182f EGE |
7743 | int ret; |
7744 | AioContext *old_context = bdrv_get_aio_context(bs); | |
f791bf7f EGE |
7745 | GLOBAL_STATE_CODE(); |
7746 | ||
7e8c182f EGE |
7747 | /* |
7748 | * Recursion phase: go through all nodes of the graph. | |
7749 | * Take care of checking that all nodes support changing AioContext | |
3202d8e4 | 7750 | * and drain them, building a linear list of callbacks to run if everything |
7e8c182f EGE |
7751 | * is successful (the transaction itself). |
7752 | */ | |
7753 | tran = tran_new(); | |
e08cc001 EGE |
7754 | visited = g_hash_table_new(NULL, NULL); |
7755 | if (ignore_child) { | |
7756 | g_hash_table_add(visited, ignore_child); | |
7757 | } | |
7758 | ret = bdrv_change_aio_context(bs, ctx, visited, tran, errp); | |
7759 | g_hash_table_destroy(visited); | |
7e8c182f EGE |
7760 | |
7761 | /* | |
7762 | * Linear phase: go through all callbacks collected in the transaction. | |
7763 | * Run all callbacks collected in the recursion to switch all nodes | |
7764 | * AioContext lock (transaction commit), or undo all changes done in the | |
7765 | * recursion (transaction abort). | |
7766 | */ | |
5d231849 KW |
7767 | |
7768 | if (!ret) { | |
7e8c182f EGE |
7769 | /* Just run clean() callbacks. No AioContext changed. */ |
7770 | tran_abort(tran); | |
5d231849 KW |
7771 | return -EPERM; |
7772 | } | |
7773 | ||
7e8c182f EGE |
7774 | /* |
7775 | * Release old AioContext, it won't be needed anymore, as all | |
7776 | * bdrv_drained_begin() have been called already. | |
7777 | */ | |
7778 | if (qemu_get_aio_context() != old_context) { | |
7779 | aio_context_release(old_context); | |
7780 | } | |
7781 | ||
7782 | /* | |
7783 | * Acquire new AioContext since bdrv_drained_end() is going to be called | |
7784 | * after we switched all nodes in the new AioContext, and the function | |
7785 | * assumes that the lock of the bs is always taken. | |
7786 | */ | |
7787 | if (qemu_get_aio_context() != ctx) { | |
7788 | aio_context_acquire(ctx); | |
7789 | } | |
53a7d041 | 7790 | |
7e8c182f | 7791 | tran_commit(tran); |
5d231849 | 7792 | |
7e8c182f EGE |
7793 | if (qemu_get_aio_context() != ctx) { |
7794 | aio_context_release(ctx); | |
7795 | } | |
7796 | ||
7797 | /* Re-acquire the old AioContext, since the caller takes and releases it. */ | |
7798 | if (qemu_get_aio_context() != old_context) { | |
7799 | aio_context_acquire(old_context); | |
7800 | } | |
7801 | ||
7802 | return 0; | |
5d231849 KW |
7803 | } |
7804 | ||
33384421 HR |
7805 | void bdrv_add_aio_context_notifier(BlockDriverState *bs, |
7806 | void (*attached_aio_context)(AioContext *new_context, void *opaque), | |
7807 | void (*detach_aio_context)(void *opaque), void *opaque) | |
7808 | { | |
7809 | BdrvAioNotifier *ban = g_new(BdrvAioNotifier, 1); | |
7810 | *ban = (BdrvAioNotifier){ | |
7811 | .attached_aio_context = attached_aio_context, | |
7812 | .detach_aio_context = detach_aio_context, | |
7813 | .opaque = opaque | |
7814 | }; | |
f791bf7f | 7815 | GLOBAL_STATE_CODE(); |
33384421 HR |
7816 | |
7817 | QLIST_INSERT_HEAD(&bs->aio_notifiers, ban, list); | |
7818 | } | |
7819 | ||
7820 | void bdrv_remove_aio_context_notifier(BlockDriverState *bs, | |
7821 | void (*attached_aio_context)(AioContext *, | |
7822 | void *), | |
7823 | void (*detach_aio_context)(void *), | |
7824 | void *opaque) | |
7825 | { | |
7826 | BdrvAioNotifier *ban, *ban_next; | |
f791bf7f | 7827 | GLOBAL_STATE_CODE(); |
33384421 HR |
7828 | |
7829 | QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_next) { | |
7830 | if (ban->attached_aio_context == attached_aio_context && | |
7831 | ban->detach_aio_context == detach_aio_context && | |
e8a095da SH |
7832 | ban->opaque == opaque && |
7833 | ban->deleted == false) | |
33384421 | 7834 | { |
e8a095da SH |
7835 | if (bs->walking_aio_notifiers) { |
7836 | ban->deleted = true; | |
7837 | } else { | |
7838 | bdrv_do_remove_aio_context_notifier(ban); | |
7839 | } | |
33384421 HR |
7840 | return; |
7841 | } | |
7842 | } | |
7843 | ||
7844 | abort(); | |
7845 | } | |
7846 | ||
77485434 | 7847 | int bdrv_amend_options(BlockDriverState *bs, QemuOpts *opts, |
d1402b50 | 7848 | BlockDriverAmendStatusCB *status_cb, void *cb_opaque, |
a3579bfa | 7849 | bool force, |
d1402b50 | 7850 | Error **errp) |
6f176b48 | 7851 | { |
f791bf7f | 7852 | GLOBAL_STATE_CODE(); |
d470ad42 | 7853 | if (!bs->drv) { |
d1402b50 | 7854 | error_setg(errp, "Node is ejected"); |
d470ad42 HR |
7855 | return -ENOMEDIUM; |
7856 | } | |
c282e1fd | 7857 | if (!bs->drv->bdrv_amend_options) { |
d1402b50 HR |
7858 | error_setg(errp, "Block driver '%s' does not support option amendment", |
7859 | bs->drv->format_name); | |
6f176b48 HR |
7860 | return -ENOTSUP; |
7861 | } | |
a3579bfa ML |
7862 | return bs->drv->bdrv_amend_options(bs, opts, status_cb, |
7863 | cb_opaque, force, errp); | |
6f176b48 | 7864 | } |
f6186f49 | 7865 | |
5d69b5ab HR |
7866 | /* |
7867 | * This function checks whether the given @to_replace is allowed to be | |
7868 | * replaced by a node that always shows the same data as @bs. This is | |
7869 | * used for example to verify whether the mirror job can replace | |
7870 | * @to_replace by the target mirrored from @bs. | |
7871 | * To be replaceable, @bs and @to_replace may either be guaranteed to | |
7872 | * always show the same data (because they are only connected through | |
7873 | * filters), or some driver may allow replacing one of its children | |
7874 | * because it can guarantee that this child's data is not visible at | |
7875 | * all (for example, for dissenting quorum children that have no other | |
7876 | * parents). | |
7877 | */ | |
7878 | bool bdrv_recurse_can_replace(BlockDriverState *bs, | |
7879 | BlockDriverState *to_replace) | |
7880 | { | |
93393e69 HR |
7881 | BlockDriverState *filtered; |
7882 | ||
b4ad82aa EGE |
7883 | GLOBAL_STATE_CODE(); |
7884 | ||
5d69b5ab HR |
7885 | if (!bs || !bs->drv) { |
7886 | return false; | |
7887 | } | |
7888 | ||
7889 | if (bs == to_replace) { | |
7890 | return true; | |
7891 | } | |
7892 | ||
7893 | /* See what the driver can do */ | |
7894 | if (bs->drv->bdrv_recurse_can_replace) { | |
7895 | return bs->drv->bdrv_recurse_can_replace(bs, to_replace); | |
7896 | } | |
7897 | ||
7898 | /* For filters without an own implementation, we can recurse on our own */ | |
93393e69 HR |
7899 | filtered = bdrv_filter_bs(bs); |
7900 | if (filtered) { | |
7901 | return bdrv_recurse_can_replace(filtered, to_replace); | |
5d69b5ab HR |
7902 | } |
7903 | ||
7904 | /* Safe default */ | |
7905 | return false; | |
7906 | } | |
7907 | ||
810803a8 HR |
7908 | /* |
7909 | * Check whether the given @node_name can be replaced by a node that | |
7910 | * has the same data as @parent_bs. If so, return @node_name's BDS; | |
7911 | * NULL otherwise. | |
7912 | * | |
7913 | * @node_name must be a (recursive) *child of @parent_bs (or this | |
7914 | * function will return NULL). | |
7915 | * | |
7916 | * The result (whether the node can be replaced or not) is only valid | |
7917 | * for as long as no graph or permission changes occur. | |
7918 | */ | |
e12f3784 WC |
7919 | BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, |
7920 | const char *node_name, Error **errp) | |
09158f00 BC |
7921 | { |
7922 | BlockDriverState *to_replace_bs = bdrv_find_node(node_name); | |
5a7e7a0b SH |
7923 | AioContext *aio_context; |
7924 | ||
f791bf7f EGE |
7925 | GLOBAL_STATE_CODE(); |
7926 | ||
09158f00 | 7927 | if (!to_replace_bs) { |
785ec4b1 | 7928 | error_setg(errp, "Failed to find node with node-name='%s'", node_name); |
09158f00 BC |
7929 | return NULL; |
7930 | } | |
7931 | ||
5a7e7a0b SH |
7932 | aio_context = bdrv_get_aio_context(to_replace_bs); |
7933 | aio_context_acquire(aio_context); | |
7934 | ||
09158f00 | 7935 | if (bdrv_op_is_blocked(to_replace_bs, BLOCK_OP_TYPE_REPLACE, errp)) { |
5a7e7a0b SH |
7936 | to_replace_bs = NULL; |
7937 | goto out; | |
09158f00 BC |
7938 | } |
7939 | ||
7940 | /* We don't want arbitrary node of the BDS chain to be replaced only the top | |
7941 | * most non filter in order to prevent data corruption. | |
7942 | * Another benefit is that this tests exclude backing files which are | |
7943 | * blocked by the backing blockers. | |
7944 | */ | |
810803a8 HR |
7945 | if (!bdrv_recurse_can_replace(parent_bs, to_replace_bs)) { |
7946 | error_setg(errp, "Cannot replace '%s' by a node mirrored from '%s', " | |
7947 | "because it cannot be guaranteed that doing so would not " | |
7948 | "lead to an abrupt change of visible data", | |
7949 | node_name, parent_bs->node_name); | |
5a7e7a0b SH |
7950 | to_replace_bs = NULL; |
7951 | goto out; | |
09158f00 BC |
7952 | } |
7953 | ||
5a7e7a0b SH |
7954 | out: |
7955 | aio_context_release(aio_context); | |
09158f00 BC |
7956 | return to_replace_bs; |
7957 | } | |
448ad91d | 7958 | |
97e2f021 HR |
7959 | /** |
7960 | * Iterates through the list of runtime option keys that are said to | |
7961 | * be "strong" for a BDS. An option is called "strong" if it changes | |
7962 | * a BDS's data. For example, the null block driver's "size" and | |
7963 | * "read-zeroes" options are strong, but its "latency-ns" option is | |
7964 | * not. | |
7965 | * | |
7966 | * If a key returned by this function ends with a dot, all options | |
7967 | * starting with that prefix are strong. | |
7968 | */ | |
7969 | static const char *const *strong_options(BlockDriverState *bs, | |
7970 | const char *const *curopt) | |
7971 | { | |
7972 | static const char *const global_options[] = { | |
7973 | "driver", "filename", NULL | |
7974 | }; | |
7975 | ||
7976 | if (!curopt) { | |
7977 | return &global_options[0]; | |
7978 | } | |
7979 | ||
7980 | curopt++; | |
7981 | if (curopt == &global_options[ARRAY_SIZE(global_options) - 1] && bs->drv) { | |
7982 | curopt = bs->drv->strong_runtime_opts; | |
7983 | } | |
7984 | ||
7985 | return (curopt && *curopt) ? curopt : NULL; | |
7986 | } | |
7987 | ||
7988 | /** | |
7989 | * Copies all strong runtime options from bs->options to the given | |
7990 | * QDict. The set of strong option keys is determined by invoking | |
7991 | * strong_options(). | |
7992 | * | |
7993 | * Returns true iff any strong option was present in bs->options (and | |
7994 | * thus copied to the target QDict) with the exception of "filename" | |
7995 | * and "driver". The caller is expected to use this value to decide | |
7996 | * whether the existence of strong options prevents the generation of | |
7997 | * a plain filename. | |
7998 | */ | |
7999 | static bool append_strong_runtime_options(QDict *d, BlockDriverState *bs) | |
8000 | { | |
8001 | bool found_any = false; | |
8002 | const char *const *option_name = NULL; | |
8003 | ||
8004 | if (!bs->drv) { | |
8005 | return false; | |
8006 | } | |
8007 | ||
8008 | while ((option_name = strong_options(bs, option_name))) { | |
8009 | bool option_given = false; | |
8010 | ||
8011 | assert(strlen(*option_name) > 0); | |
8012 | if ((*option_name)[strlen(*option_name) - 1] != '.') { | |
8013 | QObject *entry = qdict_get(bs->options, *option_name); | |
8014 | if (!entry) { | |
8015 | continue; | |
8016 | } | |
8017 | ||
8018 | qdict_put_obj(d, *option_name, qobject_ref(entry)); | |
8019 | option_given = true; | |
8020 | } else { | |
8021 | const QDictEntry *entry; | |
8022 | for (entry = qdict_first(bs->options); entry; | |
8023 | entry = qdict_next(bs->options, entry)) | |
8024 | { | |
8025 | if (strstart(qdict_entry_key(entry), *option_name, NULL)) { | |
8026 | qdict_put_obj(d, qdict_entry_key(entry), | |
8027 | qobject_ref(qdict_entry_value(entry))); | |
8028 | option_given = true; | |
8029 | } | |
8030 | } | |
8031 | } | |
8032 | ||
8033 | /* While "driver" and "filename" need to be included in a JSON filename, | |
8034 | * their existence does not prohibit generation of a plain filename. */ | |
8035 | if (!found_any && option_given && | |
8036 | strcmp(*option_name, "driver") && strcmp(*option_name, "filename")) | |
8037 | { | |
8038 | found_any = true; | |
8039 | } | |
8040 | } | |
8041 | ||
62a01a27 HR |
8042 | if (!qdict_haskey(d, "driver")) { |
8043 | /* Drivers created with bdrv_new_open_driver() may not have a | |
8044 | * @driver option. Add it here. */ | |
8045 | qdict_put_str(d, "driver", bs->drv->format_name); | |
8046 | } | |
8047 | ||
97e2f021 HR |
8048 | return found_any; |
8049 | } | |
8050 | ||
90993623 HR |
8051 | /* Note: This function may return false positives; it may return true |
8052 | * even if opening the backing file specified by bs's image header | |
8053 | * would result in exactly bs->backing. */ | |
fa8fc1d0 | 8054 | static bool bdrv_backing_overridden(BlockDriverState *bs) |
90993623 | 8055 | { |
b4ad82aa | 8056 | GLOBAL_STATE_CODE(); |
90993623 HR |
8057 | if (bs->backing) { |
8058 | return strcmp(bs->auto_backing_file, | |
8059 | bs->backing->bs->filename); | |
8060 | } else { | |
8061 | /* No backing BDS, so if the image header reports any backing | |
8062 | * file, it must have been suppressed */ | |
8063 | return bs->auto_backing_file[0] != '\0'; | |
8064 | } | |
8065 | } | |
8066 | ||
91af7014 HR |
8067 | /* Updates the following BDS fields: |
8068 | * - exact_filename: A filename which may be used for opening a block device | |
8069 | * which (mostly) equals the given BDS (even without any | |
8070 | * other options; so reading and writing must return the same | |
8071 | * results, but caching etc. may be different) | |
8072 | * - full_open_options: Options which, when given when opening a block device | |
8073 | * (without a filename), result in a BDS (mostly) | |
8074 | * equalling the given one | |
8075 | * - filename: If exact_filename is set, it is copied here. Otherwise, | |
8076 | * full_open_options is converted to a JSON object, prefixed with | |
8077 | * "json:" (for use through the JSON pseudo protocol) and put here. | |
8078 | */ | |
8079 | void bdrv_refresh_filename(BlockDriverState *bs) | |
8080 | { | |
8081 | BlockDriver *drv = bs->drv; | |
e24518e3 | 8082 | BdrvChild *child; |
52f72d6f | 8083 | BlockDriverState *primary_child_bs; |
91af7014 | 8084 | QDict *opts; |
90993623 | 8085 | bool backing_overridden; |
998b3a1e HR |
8086 | bool generate_json_filename; /* Whether our default implementation should |
8087 | fill exact_filename (false) or not (true) */ | |
91af7014 | 8088 | |
f791bf7f EGE |
8089 | GLOBAL_STATE_CODE(); |
8090 | ||
91af7014 HR |
8091 | if (!drv) { |
8092 | return; | |
8093 | } | |
8094 | ||
e24518e3 HR |
8095 | /* This BDS's file name may depend on any of its children's file names, so |
8096 | * refresh those first */ | |
8097 | QLIST_FOREACH(child, &bs->children, next) { | |
8098 | bdrv_refresh_filename(child->bs); | |
91af7014 HR |
8099 | } |
8100 | ||
bb808d5f HR |
8101 | if (bs->implicit) { |
8102 | /* For implicit nodes, just copy everything from the single child */ | |
8103 | child = QLIST_FIRST(&bs->children); | |
8104 | assert(QLIST_NEXT(child, next) == NULL); | |
8105 | ||
8106 | pstrcpy(bs->exact_filename, sizeof(bs->exact_filename), | |
8107 | child->bs->exact_filename); | |
8108 | pstrcpy(bs->filename, sizeof(bs->filename), child->bs->filename); | |
8109 | ||
cb895614 | 8110 | qobject_unref(bs->full_open_options); |
bb808d5f HR |
8111 | bs->full_open_options = qobject_ref(child->bs->full_open_options); |
8112 | ||
8113 | return; | |
8114 | } | |
8115 | ||
90993623 HR |
8116 | backing_overridden = bdrv_backing_overridden(bs); |
8117 | ||
8118 | if (bs->open_flags & BDRV_O_NO_IO) { | |
8119 | /* Without I/O, the backing file does not change anything. | |
8120 | * Therefore, in such a case (primarily qemu-img), we can | |
8121 | * pretend the backing file has not been overridden even if | |
8122 | * it technically has been. */ | |
8123 | backing_overridden = false; | |
8124 | } | |
8125 | ||
97e2f021 HR |
8126 | /* Gather the options QDict */ |
8127 | opts = qdict_new(); | |
998b3a1e HR |
8128 | generate_json_filename = append_strong_runtime_options(opts, bs); |
8129 | generate_json_filename |= backing_overridden; | |
97e2f021 HR |
8130 | |
8131 | if (drv->bdrv_gather_child_options) { | |
8132 | /* Some block drivers may not want to present all of their children's | |
8133 | * options, or name them differently from BdrvChild.name */ | |
8134 | drv->bdrv_gather_child_options(bs, opts, backing_overridden); | |
8135 | } else { | |
8136 | QLIST_FOREACH(child, &bs->children, next) { | |
25191e5f | 8137 | if (child == bs->backing && !backing_overridden) { |
97e2f021 HR |
8138 | /* We can skip the backing BDS if it has not been overridden */ |
8139 | continue; | |
8140 | } | |
8141 | ||
8142 | qdict_put(opts, child->name, | |
8143 | qobject_ref(child->bs->full_open_options)); | |
8144 | } | |
8145 | ||
8146 | if (backing_overridden && !bs->backing) { | |
8147 | /* Force no backing file */ | |
8148 | qdict_put_null(opts, "backing"); | |
8149 | } | |
8150 | } | |
8151 | ||
8152 | qobject_unref(bs->full_open_options); | |
8153 | bs->full_open_options = opts; | |
8154 | ||
52f72d6f HR |
8155 | primary_child_bs = bdrv_primary_bs(bs); |
8156 | ||
998b3a1e HR |
8157 | if (drv->bdrv_refresh_filename) { |
8158 | /* Obsolete information is of no use here, so drop the old file name | |
8159 | * information before refreshing it */ | |
8160 | bs->exact_filename[0] = '\0'; | |
8161 | ||
8162 | drv->bdrv_refresh_filename(bs); | |
52f72d6f HR |
8163 | } else if (primary_child_bs) { |
8164 | /* | |
8165 | * Try to reconstruct valid information from the underlying | |
8166 | * file -- this only works for format nodes (filter nodes | |
8167 | * cannot be probed and as such must be selected by the user | |
8168 | * either through an options dict, or through a special | |
8169 | * filename which the filter driver must construct in its | |
8170 | * .bdrv_refresh_filename() implementation). | |
8171 | */ | |
998b3a1e HR |
8172 | |
8173 | bs->exact_filename[0] = '\0'; | |
8174 | ||
fb695c74 HR |
8175 | /* |
8176 | * We can use the underlying file's filename if: | |
8177 | * - it has a filename, | |
52f72d6f | 8178 | * - the current BDS is not a filter, |
fb695c74 HR |
8179 | * - the file is a protocol BDS, and |
8180 | * - opening that file (as this BDS's format) will automatically create | |
8181 | * the BDS tree we have right now, that is: | |
8182 | * - the user did not significantly change this BDS's behavior with | |
8183 | * some explicit (strong) options | |
8184 | * - no non-file child of this BDS has been overridden by the user | |
8185 | * Both of these conditions are represented by generate_json_filename. | |
8186 | */ | |
52f72d6f HR |
8187 | if (primary_child_bs->exact_filename[0] && |
8188 | primary_child_bs->drv->bdrv_file_open && | |
8189 | !drv->is_filter && !generate_json_filename) | |
fb695c74 | 8190 | { |
52f72d6f | 8191 | strcpy(bs->exact_filename, primary_child_bs->exact_filename); |
998b3a1e HR |
8192 | } |
8193 | } | |
8194 | ||
91af7014 HR |
8195 | if (bs->exact_filename[0]) { |
8196 | pstrcpy(bs->filename, sizeof(bs->filename), bs->exact_filename); | |
97e2f021 | 8197 | } else { |
eab3a467 | 8198 | GString *json = qobject_to_json(QOBJECT(bs->full_open_options)); |
5c86bdf1 | 8199 | if (snprintf(bs->filename, sizeof(bs->filename), "json:%s", |
eab3a467 | 8200 | json->str) >= sizeof(bs->filename)) { |
5c86bdf1 EB |
8201 | /* Give user a hint if we truncated things. */ |
8202 | strcpy(bs->filename + sizeof(bs->filename) - 4, "..."); | |
8203 | } | |
eab3a467 | 8204 | g_string_free(json, true); |
91af7014 HR |
8205 | } |
8206 | } | |
e06018ad | 8207 | |
1e89d0f9 HR |
8208 | char *bdrv_dirname(BlockDriverState *bs, Error **errp) |
8209 | { | |
8210 | BlockDriver *drv = bs->drv; | |
52f72d6f | 8211 | BlockDriverState *child_bs; |
1e89d0f9 | 8212 | |
f791bf7f EGE |
8213 | GLOBAL_STATE_CODE(); |
8214 | ||
1e89d0f9 HR |
8215 | if (!drv) { |
8216 | error_setg(errp, "Node '%s' is ejected", bs->node_name); | |
8217 | return NULL; | |
8218 | } | |
8219 | ||
8220 | if (drv->bdrv_dirname) { | |
8221 | return drv->bdrv_dirname(bs, errp); | |
8222 | } | |
8223 | ||
52f72d6f HR |
8224 | child_bs = bdrv_primary_bs(bs); |
8225 | if (child_bs) { | |
8226 | return bdrv_dirname(child_bs, errp); | |
1e89d0f9 HR |
8227 | } |
8228 | ||
8229 | bdrv_refresh_filename(bs); | |
8230 | if (bs->exact_filename[0] != '\0') { | |
8231 | return path_combine(bs->exact_filename, ""); | |
8232 | } | |
8233 | ||
8234 | error_setg(errp, "Cannot generate a base directory for %s nodes", | |
8235 | drv->format_name); | |
8236 | return NULL; | |
8237 | } | |
8238 | ||
e06018ad WC |
8239 | /* |
8240 | * Hot add/remove a BDS's child. So the user can take a child offline when | |
8241 | * it is broken and take a new child online | |
8242 | */ | |
8243 | void bdrv_add_child(BlockDriverState *parent_bs, BlockDriverState *child_bs, | |
8244 | Error **errp) | |
8245 | { | |
f791bf7f | 8246 | GLOBAL_STATE_CODE(); |
e06018ad WC |
8247 | if (!parent_bs->drv || !parent_bs->drv->bdrv_add_child) { |
8248 | error_setg(errp, "The node %s does not support adding a child", | |
8249 | bdrv_get_device_or_node_name(parent_bs)); | |
8250 | return; | |
8251 | } | |
8252 | ||
774c726c SL |
8253 | /* |
8254 | * Non-zoned block drivers do not follow zoned storage constraints | |
8255 | * (i.e. sequential writes to zones). Refuse mixing zoned and non-zoned | |
8256 | * drivers in a graph. | |
8257 | */ | |
8258 | if (!parent_bs->drv->supports_zoned_children && | |
8259 | child_bs->bl.zoned == BLK_Z_HM) { | |
8260 | /* | |
8261 | * The host-aware model allows zoned storage constraints and random | |
8262 | * write. Allow mixing host-aware and non-zoned drivers. Using | |
8263 | * host-aware device as a regular device. | |
8264 | */ | |
8265 | error_setg(errp, "Cannot add a %s child to a %s parent", | |
8266 | child_bs->bl.zoned == BLK_Z_HM ? "zoned" : "non-zoned", | |
8267 | parent_bs->drv->supports_zoned_children ? | |
8268 | "support zoned children" : "not support zoned children"); | |
8269 | return; | |
8270 | } | |
8271 | ||
e06018ad WC |
8272 | if (!QLIST_EMPTY(&child_bs->parents)) { |
8273 | error_setg(errp, "The node %s already has a parent", | |
8274 | child_bs->node_name); | |
8275 | return; | |
8276 | } | |
8277 | ||
8278 | parent_bs->drv->bdrv_add_child(parent_bs, child_bs, errp); | |
8279 | } | |
8280 | ||
8281 | void bdrv_del_child(BlockDriverState *parent_bs, BdrvChild *child, Error **errp) | |
8282 | { | |
8283 | BdrvChild *tmp; | |
8284 | ||
f791bf7f | 8285 | GLOBAL_STATE_CODE(); |
e06018ad WC |
8286 | if (!parent_bs->drv || !parent_bs->drv->bdrv_del_child) { |
8287 | error_setg(errp, "The node %s does not support removing a child", | |
8288 | bdrv_get_device_or_node_name(parent_bs)); | |
8289 | return; | |
8290 | } | |
8291 | ||
8292 | QLIST_FOREACH(tmp, &parent_bs->children, next) { | |
8293 | if (tmp == child) { | |
8294 | break; | |
8295 | } | |
8296 | } | |
8297 | ||
8298 | if (!tmp) { | |
8299 | error_setg(errp, "The node %s does not have a child named %s", | |
8300 | bdrv_get_device_or_node_name(parent_bs), | |
8301 | bdrv_get_device_or_node_name(child->bs)); | |
8302 | return; | |
8303 | } | |
8304 | ||
8305 | parent_bs->drv->bdrv_del_child(parent_bs, child, errp); | |
8306 | } | |
6f7a3b53 HR |
8307 | |
8308 | int bdrv_make_empty(BdrvChild *c, Error **errp) | |
8309 | { | |
8310 | BlockDriver *drv = c->bs->drv; | |
8311 | int ret; | |
8312 | ||
f791bf7f | 8313 | GLOBAL_STATE_CODE(); |
6f7a3b53 HR |
8314 | assert(c->perm & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)); |
8315 | ||
8316 | if (!drv->bdrv_make_empty) { | |
8317 | error_setg(errp, "%s does not support emptying nodes", | |
8318 | drv->format_name); | |
8319 | return -ENOTSUP; | |
8320 | } | |
8321 | ||
8322 | ret = drv->bdrv_make_empty(c->bs); | |
8323 | if (ret < 0) { | |
8324 | error_setg_errno(errp, -ret, "Failed to empty %s", | |
8325 | c->bs->filename); | |
8326 | return ret; | |
8327 | } | |
8328 | ||
8329 | return 0; | |
8330 | } | |
9a6fc887 HR |
8331 | |
8332 | /* | |
8333 | * Return the child that @bs acts as an overlay for, and from which data may be | |
8334 | * copied in COW or COR operations. Usually this is the backing file. | |
8335 | */ | |
8336 | BdrvChild *bdrv_cow_child(BlockDriverState *bs) | |
8337 | { | |
967d7905 EGE |
8338 | IO_CODE(); |
8339 | ||
9a6fc887 HR |
8340 | if (!bs || !bs->drv) { |
8341 | return NULL; | |
8342 | } | |
8343 | ||
8344 | if (bs->drv->is_filter) { | |
8345 | return NULL; | |
8346 | } | |
8347 | ||
8348 | if (!bs->backing) { | |
8349 | return NULL; | |
8350 | } | |
8351 | ||
8352 | assert(bs->backing->role & BDRV_CHILD_COW); | |
8353 | return bs->backing; | |
8354 | } | |
8355 | ||
8356 | /* | |
8357 | * If @bs acts as a filter for exactly one of its children, return | |
8358 | * that child. | |
8359 | */ | |
8360 | BdrvChild *bdrv_filter_child(BlockDriverState *bs) | |
8361 | { | |
8362 | BdrvChild *c; | |
967d7905 | 8363 | IO_CODE(); |
9a6fc887 HR |
8364 | |
8365 | if (!bs || !bs->drv) { | |
8366 | return NULL; | |
8367 | } | |
8368 | ||
8369 | if (!bs->drv->is_filter) { | |
8370 | return NULL; | |
8371 | } | |
8372 | ||
8373 | /* Only one of @backing or @file may be used */ | |
8374 | assert(!(bs->backing && bs->file)); | |
8375 | ||
8376 | c = bs->backing ?: bs->file; | |
8377 | if (!c) { | |
8378 | return NULL; | |
8379 | } | |
8380 | ||
8381 | assert(c->role & BDRV_CHILD_FILTERED); | |
8382 | return c; | |
8383 | } | |
8384 | ||
8385 | /* | |
8386 | * Return either the result of bdrv_cow_child() or bdrv_filter_child(), | |
8387 | * whichever is non-NULL. | |
8388 | * | |
8389 | * Return NULL if both are NULL. | |
8390 | */ | |
8391 | BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs) | |
8392 | { | |
8393 | BdrvChild *cow_child = bdrv_cow_child(bs); | |
8394 | BdrvChild *filter_child = bdrv_filter_child(bs); | |
967d7905 | 8395 | IO_CODE(); |
9a6fc887 HR |
8396 | |
8397 | /* Filter nodes cannot have COW backing files */ | |
8398 | assert(!(cow_child && filter_child)); | |
8399 | ||
8400 | return cow_child ?: filter_child; | |
8401 | } | |
8402 | ||
8403 | /* | |
8404 | * Return the primary child of this node: For filters, that is the | |
8405 | * filtered child. For other nodes, that is usually the child storing | |
8406 | * metadata. | |
8407 | * (A generally more helpful description is that this is (usually) the | |
8408 | * child that has the same filename as @bs.) | |
8409 | * | |
8410 | * Drivers do not necessarily have a primary child; for example quorum | |
8411 | * does not. | |
8412 | */ | |
8413 | BdrvChild *bdrv_primary_child(BlockDriverState *bs) | |
8414 | { | |
8415 | BdrvChild *c, *found = NULL; | |
967d7905 | 8416 | IO_CODE(); |
9a6fc887 HR |
8417 | |
8418 | QLIST_FOREACH(c, &bs->children, next) { | |
8419 | if (c->role & BDRV_CHILD_PRIMARY) { | |
8420 | assert(!found); | |
8421 | found = c; | |
8422 | } | |
8423 | } | |
8424 | ||
8425 | return found; | |
8426 | } | |
d38d7eb8 HR |
8427 | |
8428 | static BlockDriverState *bdrv_do_skip_filters(BlockDriverState *bs, | |
8429 | bool stop_on_explicit_filter) | |
8430 | { | |
8431 | BdrvChild *c; | |
8432 | ||
8433 | if (!bs) { | |
8434 | return NULL; | |
8435 | } | |
8436 | ||
8437 | while (!(stop_on_explicit_filter && !bs->implicit)) { | |
8438 | c = bdrv_filter_child(bs); | |
8439 | if (!c) { | |
8440 | /* | |
8441 | * A filter that is embedded in a working block graph must | |
8442 | * have a child. Assert this here so this function does | |
8443 | * not return a filter node that is not expected by the | |
8444 | * caller. | |
8445 | */ | |
8446 | assert(!bs->drv || !bs->drv->is_filter); | |
8447 | break; | |
8448 | } | |
8449 | bs = c->bs; | |
8450 | } | |
8451 | /* | |
8452 | * Note that this treats nodes with bs->drv == NULL as not being | |
8453 | * filters (bs->drv == NULL should be replaced by something else | |
8454 | * anyway). | |
8455 | * The advantage of this behavior is that this function will thus | |
8456 | * always return a non-NULL value (given a non-NULL @bs). | |
8457 | */ | |
8458 | ||
8459 | return bs; | |
8460 | } | |
8461 | ||
8462 | /* | |
8463 | * Return the first BDS that has not been added implicitly or that | |
8464 | * does not have a filtered child down the chain starting from @bs | |
8465 | * (including @bs itself). | |
8466 | */ | |
8467 | BlockDriverState *bdrv_skip_implicit_filters(BlockDriverState *bs) | |
8468 | { | |
b4ad82aa | 8469 | GLOBAL_STATE_CODE(); |
d38d7eb8 HR |
8470 | return bdrv_do_skip_filters(bs, true); |
8471 | } | |
8472 | ||
8473 | /* | |
8474 | * Return the first BDS that does not have a filtered child down the | |
8475 | * chain starting from @bs (including @bs itself). | |
8476 | */ | |
8477 | BlockDriverState *bdrv_skip_filters(BlockDriverState *bs) | |
8478 | { | |
967d7905 | 8479 | IO_CODE(); |
d38d7eb8 HR |
8480 | return bdrv_do_skip_filters(bs, false); |
8481 | } | |
8482 | ||
8483 | /* | |
8484 | * For a backing chain, return the first non-filter backing image of | |
8485 | * the first non-filter image. | |
8486 | */ | |
8487 | BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs) | |
8488 | { | |
967d7905 | 8489 | IO_CODE(); |
d38d7eb8 HR |
8490 | return bdrv_skip_filters(bdrv_cow_bs(bdrv_skip_filters(bs))); |
8491 | } | |
0bc329fb HR |
8492 | |
8493 | /** | |
8494 | * Check whether [offset, offset + bytes) overlaps with the cached | |
8495 | * block-status data region. | |
8496 | * | |
8497 | * If so, and @pnum is not NULL, set *pnum to `bsc.data_end - offset`, | |
8498 | * which is what bdrv_bsc_is_data()'s interface needs. | |
8499 | * Otherwise, *pnum is not touched. | |
8500 | */ | |
8501 | static bool bdrv_bsc_range_overlaps_locked(BlockDriverState *bs, | |
8502 | int64_t offset, int64_t bytes, | |
8503 | int64_t *pnum) | |
8504 | { | |
8505 | BdrvBlockStatusCache *bsc = qatomic_rcu_read(&bs->block_status_cache); | |
8506 | bool overlaps; | |
8507 | ||
8508 | overlaps = | |
8509 | qatomic_read(&bsc->valid) && | |
8510 | ranges_overlap(offset, bytes, bsc->data_start, | |
8511 | bsc->data_end - bsc->data_start); | |
8512 | ||
8513 | if (overlaps && pnum) { | |
8514 | *pnum = bsc->data_end - offset; | |
8515 | } | |
8516 | ||
8517 | return overlaps; | |
8518 | } | |
8519 | ||
8520 | /** | |
8521 | * See block_int.h for this function's documentation. | |
8522 | */ | |
8523 | bool bdrv_bsc_is_data(BlockDriverState *bs, int64_t offset, int64_t *pnum) | |
8524 | { | |
967d7905 | 8525 | IO_CODE(); |
0bc329fb | 8526 | RCU_READ_LOCK_GUARD(); |
0bc329fb HR |
8527 | return bdrv_bsc_range_overlaps_locked(bs, offset, 1, pnum); |
8528 | } | |
8529 | ||
8530 | /** | |
8531 | * See block_int.h for this function's documentation. | |
8532 | */ | |
8533 | void bdrv_bsc_invalidate_range(BlockDriverState *bs, | |
8534 | int64_t offset, int64_t bytes) | |
8535 | { | |
967d7905 | 8536 | IO_CODE(); |
0bc329fb HR |
8537 | RCU_READ_LOCK_GUARD(); |
8538 | ||
8539 | if (bdrv_bsc_range_overlaps_locked(bs, offset, bytes, NULL)) { | |
8540 | qatomic_set(&bs->block_status_cache->valid, false); | |
8541 | } | |
8542 | } | |
8543 | ||
8544 | /** | |
8545 | * See block_int.h for this function's documentation. | |
8546 | */ | |
8547 | void bdrv_bsc_fill(BlockDriverState *bs, int64_t offset, int64_t bytes) | |
8548 | { | |
8549 | BdrvBlockStatusCache *new_bsc = g_new(BdrvBlockStatusCache, 1); | |
8550 | BdrvBlockStatusCache *old_bsc; | |
967d7905 | 8551 | IO_CODE(); |
0bc329fb HR |
8552 | |
8553 | *new_bsc = (BdrvBlockStatusCache) { | |
8554 | .valid = true, | |
8555 | .data_start = offset, | |
8556 | .data_end = offset + bytes, | |
8557 | }; | |
8558 | ||
8559 | QEMU_LOCK_GUARD(&bs->bsc_modify_lock); | |
8560 | ||
8561 | old_bsc = qatomic_rcu_read(&bs->block_status_cache); | |
8562 | qatomic_rcu_set(&bs->block_status_cache, new_bsc); | |
8563 | if (old_bsc) { | |
8564 | g_free_rcu(old_bsc, rcu); | |
8565 | } | |
8566 | } |