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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 |
5fafdf24 | 5 | * |
fc01f7e7 FB |
6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
7 | * of this software and associated documentation files (the "Software"), to deal | |
8 | * in the Software without restriction, including without limitation the rights | |
9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell | |
10 | * copies of the Software, and to permit persons to whom the Software is | |
11 | * furnished to do so, subject to the following conditions: | |
12 | * | |
13 | * The above copyright notice and this permission notice shall be included in | |
14 | * all copies or substantial portions of the Software. | |
15 | * | |
16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, | |
21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN | |
22 | * THE SOFTWARE. | |
23 | */ | |
e688df6b | 24 | |
d38ea87a | 25 | #include "qemu/osdep.h" |
0ab8ed18 | 26 | #include "block/trace.h" |
737e150e PB |
27 | #include "block/block_int.h" |
28 | #include "block/blockjob.h" | |
0c9b70d5 | 29 | #include "block/fuse.h" |
cd7fca95 | 30 | #include "block/nbd.h" |
609f45ea | 31 | #include "block/qdict.h" |
d49b6836 | 32 | #include "qemu/error-report.h" |
5e5733e5 | 33 | #include "block/module_block.h" |
db725815 | 34 | #include "qemu/main-loop.h" |
1de7afc9 | 35 | #include "qemu/module.h" |
e688df6b | 36 | #include "qapi/error.h" |
452fcdbc | 37 | #include "qapi/qmp/qdict.h" |
7b1b5d19 | 38 | #include "qapi/qmp/qjson.h" |
e59a0cf1 | 39 | #include "qapi/qmp/qnull.h" |
fc81fa1e | 40 | #include "qapi/qmp/qstring.h" |
e1d74bc6 KW |
41 | #include "qapi/qobject-output-visitor.h" |
42 | #include "qapi/qapi-visit-block-core.h" | |
bfb197e0 | 43 | #include "sysemu/block-backend.h" |
9c17d615 | 44 | #include "sysemu/sysemu.h" |
1de7afc9 | 45 | #include "qemu/notify.h" |
922a01a0 | 46 | #include "qemu/option.h" |
10817bf0 | 47 | #include "qemu/coroutine.h" |
c13163fb | 48 | #include "block/qapi.h" |
1de7afc9 | 49 | #include "qemu/timer.h" |
f348b6d1 VB |
50 | #include "qemu/cutils.h" |
51 | #include "qemu/id.h" | |
b0defa83 | 52 | #include "qemu/transactions.h" |
21c2283e | 53 | #include "block/coroutines.h" |
fc01f7e7 | 54 | |
71e72a19 | 55 | #ifdef CONFIG_BSD |
7674e7bf | 56 | #include <sys/ioctl.h> |
72cf2d4f | 57 | #include <sys/queue.h> |
c5e97233 | 58 | #ifndef __DragonFly__ |
7674e7bf FB |
59 | #include <sys/disk.h> |
60 | #endif | |
c5e97233 | 61 | #endif |
7674e7bf | 62 | |
49dc768d AL |
63 | #ifdef _WIN32 |
64 | #include <windows.h> | |
65 | #endif | |
66 | ||
1c9805a3 SH |
67 | #define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */ |
68 | ||
dc364f4c BC |
69 | static QTAILQ_HEAD(, BlockDriverState) graph_bdrv_states = |
70 | QTAILQ_HEAD_INITIALIZER(graph_bdrv_states); | |
71 | ||
2c1d04e0 HR |
72 | static QTAILQ_HEAD(, BlockDriverState) all_bdrv_states = |
73 | QTAILQ_HEAD_INITIALIZER(all_bdrv_states); | |
74 | ||
8a22f02a SH |
75 | static QLIST_HEAD(, BlockDriver) bdrv_drivers = |
76 | QLIST_HEAD_INITIALIZER(bdrv_drivers); | |
ea2384d3 | 77 | |
5b363937 HR |
78 | static BlockDriverState *bdrv_open_inherit(const char *filename, |
79 | const char *reference, | |
80 | QDict *options, int flags, | |
81 | BlockDriverState *parent, | |
bd86fb99 | 82 | const BdrvChildClass *child_class, |
272c02ea | 83 | BdrvChildRole child_role, |
5b363937 | 84 | Error **errp); |
f3930ed0 | 85 | |
0978623e VSO |
86 | static void bdrv_replace_child_noperm(BdrvChild *child, |
87 | BlockDriverState *new_bs); | |
88 | ||
53e96d1e VSO |
89 | static int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue |
90 | *queue, Error **errp); | |
91 | static void bdrv_reopen_commit(BDRVReopenState *reopen_state); | |
92 | static void bdrv_reopen_abort(BDRVReopenState *reopen_state); | |
93 | ||
eb852011 MA |
94 | /* If non-zero, use only whitelisted block drivers */ |
95 | static int use_bdrv_whitelist; | |
96 | ||
9e0b22f4 SH |
97 | #ifdef _WIN32 |
98 | static int is_windows_drive_prefix(const char *filename) | |
99 | { | |
100 | return (((filename[0] >= 'a' && filename[0] <= 'z') || | |
101 | (filename[0] >= 'A' && filename[0] <= 'Z')) && | |
102 | filename[1] == ':'); | |
103 | } | |
104 | ||
105 | int is_windows_drive(const char *filename) | |
106 | { | |
107 | if (is_windows_drive_prefix(filename) && | |
108 | filename[2] == '\0') | |
109 | return 1; | |
110 | if (strstart(filename, "\\\\.\\", NULL) || | |
111 | strstart(filename, "//./", NULL)) | |
112 | return 1; | |
113 | return 0; | |
114 | } | |
115 | #endif | |
116 | ||
339064d5 KW |
117 | size_t bdrv_opt_mem_align(BlockDriverState *bs) |
118 | { | |
119 | if (!bs || !bs->drv) { | |
459b4e66 | 120 | /* page size or 4k (hdd sector size) should be on the safe side */ |
038adc2f | 121 | return MAX(4096, qemu_real_host_page_size); |
339064d5 KW |
122 | } |
123 | ||
124 | return bs->bl.opt_mem_alignment; | |
125 | } | |
126 | ||
4196d2f0 DL |
127 | size_t bdrv_min_mem_align(BlockDriverState *bs) |
128 | { | |
129 | if (!bs || !bs->drv) { | |
459b4e66 | 130 | /* page size or 4k (hdd sector size) should be on the safe side */ |
038adc2f | 131 | return MAX(4096, qemu_real_host_page_size); |
4196d2f0 DL |
132 | } |
133 | ||
134 | return bs->bl.min_mem_alignment; | |
135 | } | |
136 | ||
9e0b22f4 | 137 | /* check if the path starts with "<protocol>:" */ |
5c98415b | 138 | int path_has_protocol(const char *path) |
9e0b22f4 | 139 | { |
947995c0 PB |
140 | const char *p; |
141 | ||
9e0b22f4 SH |
142 | #ifdef _WIN32 |
143 | if (is_windows_drive(path) || | |
144 | is_windows_drive_prefix(path)) { | |
145 | return 0; | |
146 | } | |
947995c0 PB |
147 | p = path + strcspn(path, ":/\\"); |
148 | #else | |
149 | p = path + strcspn(path, ":/"); | |
9e0b22f4 SH |
150 | #endif |
151 | ||
947995c0 | 152 | return *p == ':'; |
9e0b22f4 SH |
153 | } |
154 | ||
83f64091 | 155 | int path_is_absolute(const char *path) |
3b0d4f61 | 156 | { |
21664424 FB |
157 | #ifdef _WIN32 |
158 | /* specific case for names like: "\\.\d:" */ | |
f53f4da9 | 159 | if (is_windows_drive(path) || is_windows_drive_prefix(path)) { |
21664424 | 160 | return 1; |
f53f4da9 PB |
161 | } |
162 | return (*path == '/' || *path == '\\'); | |
3b9f94e1 | 163 | #else |
f53f4da9 | 164 | return (*path == '/'); |
3b9f94e1 | 165 | #endif |
3b0d4f61 FB |
166 | } |
167 | ||
009b03aa | 168 | /* if filename is absolute, just return its duplicate. Otherwise, build a |
83f64091 FB |
169 | path to it by considering it is relative to base_path. URL are |
170 | supported. */ | |
009b03aa | 171 | char *path_combine(const char *base_path, const char *filename) |
3b0d4f61 | 172 | { |
009b03aa | 173 | const char *protocol_stripped = NULL; |
83f64091 | 174 | const char *p, *p1; |
009b03aa | 175 | char *result; |
83f64091 FB |
176 | int len; |
177 | ||
83f64091 | 178 | if (path_is_absolute(filename)) { |
009b03aa HR |
179 | return g_strdup(filename); |
180 | } | |
0d54a6fe | 181 | |
009b03aa HR |
182 | if (path_has_protocol(base_path)) { |
183 | protocol_stripped = strchr(base_path, ':'); | |
184 | if (protocol_stripped) { | |
185 | protocol_stripped++; | |
0d54a6fe | 186 | } |
009b03aa HR |
187 | } |
188 | p = protocol_stripped ?: base_path; | |
0d54a6fe | 189 | |
009b03aa | 190 | p1 = strrchr(base_path, '/'); |
3b9f94e1 | 191 | #ifdef _WIN32 |
009b03aa HR |
192 | { |
193 | const char *p2; | |
194 | p2 = strrchr(base_path, '\\'); | |
195 | if (!p1 || p2 > p1) { | |
196 | p1 = p2; | |
3b9f94e1 | 197 | } |
009b03aa | 198 | } |
3b9f94e1 | 199 | #endif |
009b03aa HR |
200 | if (p1) { |
201 | p1++; | |
202 | } else { | |
203 | p1 = base_path; | |
204 | } | |
205 | if (p1 > p) { | |
206 | p = p1; | |
3b0d4f61 | 207 | } |
009b03aa HR |
208 | len = p - base_path; |
209 | ||
210 | result = g_malloc(len + strlen(filename) + 1); | |
211 | memcpy(result, base_path, len); | |
212 | strcpy(result + len, filename); | |
213 | ||
214 | return result; | |
215 | } | |
216 | ||
03c320d8 HR |
217 | /* |
218 | * Helper function for bdrv_parse_filename() implementations to remove optional | |
219 | * protocol prefixes (especially "file:") from a filename and for putting the | |
220 | * stripped filename into the options QDict if there is such a prefix. | |
221 | */ | |
222 | void bdrv_parse_filename_strip_prefix(const char *filename, const char *prefix, | |
223 | QDict *options) | |
224 | { | |
225 | if (strstart(filename, prefix, &filename)) { | |
226 | /* Stripping the explicit protocol prefix may result in a protocol | |
227 | * prefix being (wrongly) detected (if the filename contains a colon) */ | |
228 | if (path_has_protocol(filename)) { | |
18cf67c5 | 229 | GString *fat_filename; |
03c320d8 HR |
230 | |
231 | /* This means there is some colon before the first slash; therefore, | |
232 | * this cannot be an absolute path */ | |
233 | assert(!path_is_absolute(filename)); | |
234 | ||
235 | /* And we can thus fix the protocol detection issue by prefixing it | |
236 | * by "./" */ | |
18cf67c5 MA |
237 | fat_filename = g_string_new("./"); |
238 | g_string_append(fat_filename, filename); | |
03c320d8 | 239 | |
18cf67c5 | 240 | assert(!path_has_protocol(fat_filename->str)); |
03c320d8 | 241 | |
18cf67c5 MA |
242 | qdict_put(options, "filename", |
243 | qstring_from_gstring(fat_filename)); | |
03c320d8 HR |
244 | } else { |
245 | /* If no protocol prefix was detected, we can use the shortened | |
246 | * filename as-is */ | |
247 | qdict_put_str(options, "filename", filename); | |
248 | } | |
249 | } | |
250 | } | |
251 | ||
252 | ||
9c5e6594 KW |
253 | /* Returns whether the image file is opened as read-only. Note that this can |
254 | * return false and writing to the image file is still not possible because the | |
255 | * image is inactivated. */ | |
93ed524e JC |
256 | bool bdrv_is_read_only(BlockDriverState *bs) |
257 | { | |
258 | return bs->read_only; | |
259 | } | |
260 | ||
54a32bfe KW |
261 | int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, |
262 | bool ignore_allow_rdw, Error **errp) | |
fe5241bf | 263 | { |
e2b8247a JC |
264 | /* Do not set read_only if copy_on_read is enabled */ |
265 | if (bs->copy_on_read && read_only) { | |
266 | error_setg(errp, "Can't set node '%s' to r/o with copy-on-read enabled", | |
267 | bdrv_get_device_or_node_name(bs)); | |
268 | return -EINVAL; | |
269 | } | |
270 | ||
d6fcdf06 | 271 | /* Do not clear read_only if it is prohibited */ |
54a32bfe KW |
272 | if (!read_only && !(bs->open_flags & BDRV_O_ALLOW_RDWR) && |
273 | !ignore_allow_rdw) | |
274 | { | |
d6fcdf06 JC |
275 | error_setg(errp, "Node '%s' is read only", |
276 | bdrv_get_device_or_node_name(bs)); | |
277 | return -EPERM; | |
278 | } | |
279 | ||
45803a03 JC |
280 | return 0; |
281 | } | |
282 | ||
eaa2410f KW |
283 | /* |
284 | * Called by a driver that can only provide a read-only image. | |
285 | * | |
286 | * Returns 0 if the node is already read-only or it could switch the node to | |
287 | * read-only because BDRV_O_AUTO_RDONLY is set. | |
288 | * | |
289 | * Returns -EACCES if the node is read-write and BDRV_O_AUTO_RDONLY is not set | |
290 | * or bdrv_can_set_read_only() forbids making the node read-only. If @errmsg | |
291 | * is not NULL, it is used as the error message for the Error object. | |
292 | */ | |
293 | int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, | |
294 | Error **errp) | |
45803a03 JC |
295 | { |
296 | int ret = 0; | |
297 | ||
eaa2410f KW |
298 | if (!(bs->open_flags & BDRV_O_RDWR)) { |
299 | return 0; | |
300 | } | |
301 | if (!(bs->open_flags & BDRV_O_AUTO_RDONLY)) { | |
302 | goto fail; | |
45803a03 JC |
303 | } |
304 | ||
eaa2410f KW |
305 | ret = bdrv_can_set_read_only(bs, true, false, NULL); |
306 | if (ret < 0) { | |
307 | goto fail; | |
eeae6a59 KW |
308 | } |
309 | ||
eaa2410f KW |
310 | bs->read_only = true; |
311 | bs->open_flags &= ~BDRV_O_RDWR; | |
312 | ||
e2b8247a | 313 | return 0; |
eaa2410f KW |
314 | |
315 | fail: | |
316 | error_setg(errp, "%s", errmsg ?: "Image is read-only"); | |
317 | return -EACCES; | |
fe5241bf JC |
318 | } |
319 | ||
645ae7d8 HR |
320 | /* |
321 | * If @backing is empty, this function returns NULL without setting | |
322 | * @errp. In all other cases, NULL will only be returned with @errp | |
323 | * set. | |
324 | * | |
325 | * Therefore, a return value of NULL without @errp set means that | |
326 | * there is no backing file; if @errp is set, there is one but its | |
327 | * absolute filename cannot be generated. | |
328 | */ | |
329 | char *bdrv_get_full_backing_filename_from_filename(const char *backed, | |
330 | const char *backing, | |
331 | Error **errp) | |
dc5a1371 | 332 | { |
645ae7d8 HR |
333 | if (backing[0] == '\0') { |
334 | return NULL; | |
335 | } else if (path_has_protocol(backing) || path_is_absolute(backing)) { | |
336 | return g_strdup(backing); | |
9f07429e HR |
337 | } else if (backed[0] == '\0' || strstart(backed, "json:", NULL)) { |
338 | error_setg(errp, "Cannot use relative backing file names for '%s'", | |
339 | backed); | |
645ae7d8 | 340 | return NULL; |
dc5a1371 | 341 | } else { |
645ae7d8 | 342 | return path_combine(backed, backing); |
dc5a1371 PB |
343 | } |
344 | } | |
345 | ||
9f4793d8 HR |
346 | /* |
347 | * If @filename is empty or NULL, this function returns NULL without | |
348 | * setting @errp. In all other cases, NULL will only be returned with | |
349 | * @errp set. | |
350 | */ | |
351 | static char *bdrv_make_absolute_filename(BlockDriverState *relative_to, | |
352 | const char *filename, Error **errp) | |
0a82855a | 353 | { |
8df68616 | 354 | char *dir, *full_name; |
9f4793d8 | 355 | |
8df68616 HR |
356 | if (!filename || filename[0] == '\0') { |
357 | return NULL; | |
358 | } else if (path_has_protocol(filename) || path_is_absolute(filename)) { | |
359 | return g_strdup(filename); | |
360 | } | |
9f07429e | 361 | |
8df68616 HR |
362 | dir = bdrv_dirname(relative_to, errp); |
363 | if (!dir) { | |
364 | return NULL; | |
365 | } | |
f30c66ba | 366 | |
8df68616 HR |
367 | full_name = g_strconcat(dir, filename, NULL); |
368 | g_free(dir); | |
369 | return full_name; | |
9f4793d8 HR |
370 | } |
371 | ||
372 | char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp) | |
373 | { | |
374 | return bdrv_make_absolute_filename(bs, bs->backing_file, errp); | |
0a82855a HR |
375 | } |
376 | ||
0eb7217e SH |
377 | void bdrv_register(BlockDriver *bdrv) |
378 | { | |
a15f08dc | 379 | assert(bdrv->format_name); |
8a22f02a | 380 | QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list); |
ea2384d3 | 381 | } |
b338082b | 382 | |
e4e9986b MA |
383 | BlockDriverState *bdrv_new(void) |
384 | { | |
385 | BlockDriverState *bs; | |
386 | int i; | |
387 | ||
5839e53b | 388 | bs = g_new0(BlockDriverState, 1); |
e4654d2d | 389 | QLIST_INIT(&bs->dirty_bitmaps); |
fbe40ff7 FZ |
390 | for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { |
391 | QLIST_INIT(&bs->op_blockers[i]); | |
392 | } | |
d616b224 | 393 | notifier_with_return_list_init(&bs->before_write_notifiers); |
3783fa3d | 394 | qemu_co_mutex_init(&bs->reqs_lock); |
2119882c | 395 | qemu_mutex_init(&bs->dirty_bitmap_mutex); |
9fcb0251 | 396 | bs->refcnt = 1; |
dcd04228 | 397 | bs->aio_context = qemu_get_aio_context(); |
d7d512f6 | 398 | |
3ff2f67a EY |
399 | qemu_co_queue_init(&bs->flush_queue); |
400 | ||
0f12264e KW |
401 | for (i = 0; i < bdrv_drain_all_count; i++) { |
402 | bdrv_drained_begin(bs); | |
403 | } | |
404 | ||
2c1d04e0 HR |
405 | QTAILQ_INSERT_TAIL(&all_bdrv_states, bs, bs_list); |
406 | ||
b338082b FB |
407 | return bs; |
408 | } | |
409 | ||
88d88798 | 410 | static BlockDriver *bdrv_do_find_format(const char *format_name) |
ea2384d3 FB |
411 | { |
412 | BlockDriver *drv1; | |
88d88798 | 413 | |
8a22f02a SH |
414 | QLIST_FOREACH(drv1, &bdrv_drivers, list) { |
415 | if (!strcmp(drv1->format_name, format_name)) { | |
ea2384d3 | 416 | return drv1; |
8a22f02a | 417 | } |
ea2384d3 | 418 | } |
88d88798 | 419 | |
ea2384d3 FB |
420 | return NULL; |
421 | } | |
422 | ||
88d88798 MM |
423 | BlockDriver *bdrv_find_format(const char *format_name) |
424 | { | |
425 | BlockDriver *drv1; | |
426 | int i; | |
427 | ||
428 | drv1 = bdrv_do_find_format(format_name); | |
429 | if (drv1) { | |
430 | return drv1; | |
431 | } | |
432 | ||
433 | /* The driver isn't registered, maybe we need to load a module */ | |
434 | for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); ++i) { | |
435 | if (!strcmp(block_driver_modules[i].format_name, format_name)) { | |
436 | block_module_load_one(block_driver_modules[i].library_name); | |
437 | break; | |
438 | } | |
439 | } | |
440 | ||
441 | return bdrv_do_find_format(format_name); | |
442 | } | |
443 | ||
9ac404c5 | 444 | static int bdrv_format_is_whitelisted(const char *format_name, bool read_only) |
eb852011 | 445 | { |
b64ec4e4 FZ |
446 | static const char *whitelist_rw[] = { |
447 | CONFIG_BDRV_RW_WHITELIST | |
859aef02 | 448 | NULL |
b64ec4e4 FZ |
449 | }; |
450 | static const char *whitelist_ro[] = { | |
451 | CONFIG_BDRV_RO_WHITELIST | |
859aef02 | 452 | NULL |
eb852011 MA |
453 | }; |
454 | const char **p; | |
455 | ||
b64ec4e4 | 456 | if (!whitelist_rw[0] && !whitelist_ro[0]) { |
eb852011 | 457 | return 1; /* no whitelist, anything goes */ |
b64ec4e4 | 458 | } |
eb852011 | 459 | |
b64ec4e4 | 460 | for (p = whitelist_rw; *p; p++) { |
9ac404c5 | 461 | if (!strcmp(format_name, *p)) { |
eb852011 MA |
462 | return 1; |
463 | } | |
464 | } | |
b64ec4e4 FZ |
465 | if (read_only) { |
466 | for (p = whitelist_ro; *p; p++) { | |
9ac404c5 | 467 | if (!strcmp(format_name, *p)) { |
b64ec4e4 FZ |
468 | return 1; |
469 | } | |
470 | } | |
471 | } | |
eb852011 MA |
472 | return 0; |
473 | } | |
474 | ||
9ac404c5 AS |
475 | int bdrv_is_whitelisted(BlockDriver *drv, bool read_only) |
476 | { | |
477 | return bdrv_format_is_whitelisted(drv->format_name, read_only); | |
478 | } | |
479 | ||
e6ff69bf DB |
480 | bool bdrv_uses_whitelist(void) |
481 | { | |
482 | return use_bdrv_whitelist; | |
483 | } | |
484 | ||
5b7e1542 ZYW |
485 | typedef struct CreateCo { |
486 | BlockDriver *drv; | |
487 | char *filename; | |
83d0521a | 488 | QemuOpts *opts; |
5b7e1542 | 489 | int ret; |
cc84d90f | 490 | Error *err; |
5b7e1542 ZYW |
491 | } CreateCo; |
492 | ||
493 | static void coroutine_fn bdrv_create_co_entry(void *opaque) | |
494 | { | |
cc84d90f HR |
495 | Error *local_err = NULL; |
496 | int ret; | |
497 | ||
5b7e1542 ZYW |
498 | CreateCo *cco = opaque; |
499 | assert(cco->drv); | |
500 | ||
b92902df ML |
501 | ret = cco->drv->bdrv_co_create_opts(cco->drv, |
502 | cco->filename, cco->opts, &local_err); | |
621ff94d | 503 | error_propagate(&cco->err, local_err); |
cc84d90f | 504 | cco->ret = ret; |
5b7e1542 ZYW |
505 | } |
506 | ||
0e7e1989 | 507 | int bdrv_create(BlockDriver *drv, const char* filename, |
83d0521a | 508 | QemuOpts *opts, Error **errp) |
ea2384d3 | 509 | { |
5b7e1542 ZYW |
510 | int ret; |
511 | ||
512 | Coroutine *co; | |
513 | CreateCo cco = { | |
514 | .drv = drv, | |
515 | .filename = g_strdup(filename), | |
83d0521a | 516 | .opts = opts, |
5b7e1542 | 517 | .ret = NOT_DONE, |
cc84d90f | 518 | .err = NULL, |
5b7e1542 ZYW |
519 | }; |
520 | ||
efc75e2a | 521 | if (!drv->bdrv_co_create_opts) { |
cc84d90f | 522 | error_setg(errp, "Driver '%s' does not support image creation", drv->format_name); |
80168bff LC |
523 | ret = -ENOTSUP; |
524 | goto out; | |
5b7e1542 ZYW |
525 | } |
526 | ||
527 | if (qemu_in_coroutine()) { | |
528 | /* Fast-path if already in coroutine context */ | |
529 | bdrv_create_co_entry(&cco); | |
530 | } else { | |
0b8b8753 PB |
531 | co = qemu_coroutine_create(bdrv_create_co_entry, &cco); |
532 | qemu_coroutine_enter(co); | |
5b7e1542 | 533 | while (cco.ret == NOT_DONE) { |
b47ec2c4 | 534 | aio_poll(qemu_get_aio_context(), true); |
5b7e1542 ZYW |
535 | } |
536 | } | |
537 | ||
538 | ret = cco.ret; | |
cc84d90f | 539 | if (ret < 0) { |
84d18f06 | 540 | if (cco.err) { |
cc84d90f HR |
541 | error_propagate(errp, cco.err); |
542 | } else { | |
543 | error_setg_errno(errp, -ret, "Could not create image"); | |
544 | } | |
545 | } | |
0e7e1989 | 546 | |
80168bff LC |
547 | out: |
548 | g_free(cco.filename); | |
5b7e1542 | 549 | return ret; |
ea2384d3 FB |
550 | } |
551 | ||
fd17146c HR |
552 | /** |
553 | * Helper function for bdrv_create_file_fallback(): Resize @blk to at | |
554 | * least the given @minimum_size. | |
555 | * | |
556 | * On success, return @blk's actual length. | |
557 | * Otherwise, return -errno. | |
558 | */ | |
559 | static int64_t create_file_fallback_truncate(BlockBackend *blk, | |
560 | int64_t minimum_size, Error **errp) | |
84a12e66 | 561 | { |
cc84d90f | 562 | Error *local_err = NULL; |
fd17146c | 563 | int64_t size; |
cc84d90f | 564 | int ret; |
84a12e66 | 565 | |
8c6242b6 KW |
566 | ret = blk_truncate(blk, minimum_size, false, PREALLOC_MODE_OFF, 0, |
567 | &local_err); | |
fd17146c HR |
568 | if (ret < 0 && ret != -ENOTSUP) { |
569 | error_propagate(errp, local_err); | |
570 | return ret; | |
571 | } | |
572 | ||
573 | size = blk_getlength(blk); | |
574 | if (size < 0) { | |
575 | error_free(local_err); | |
576 | error_setg_errno(errp, -size, | |
577 | "Failed to inquire the new image file's length"); | |
578 | return size; | |
579 | } | |
580 | ||
581 | if (size < minimum_size) { | |
582 | /* Need to grow the image, but we failed to do that */ | |
583 | error_propagate(errp, local_err); | |
584 | return -ENOTSUP; | |
585 | } | |
586 | ||
587 | error_free(local_err); | |
588 | local_err = NULL; | |
589 | ||
590 | return size; | |
591 | } | |
592 | ||
593 | /** | |
594 | * Helper function for bdrv_create_file_fallback(): Zero the first | |
595 | * sector to remove any potentially pre-existing image header. | |
596 | */ | |
597 | static int create_file_fallback_zero_first_sector(BlockBackend *blk, | |
598 | int64_t current_size, | |
599 | Error **errp) | |
600 | { | |
601 | int64_t bytes_to_clear; | |
602 | int ret; | |
603 | ||
604 | bytes_to_clear = MIN(current_size, BDRV_SECTOR_SIZE); | |
605 | if (bytes_to_clear) { | |
606 | ret = blk_pwrite_zeroes(blk, 0, bytes_to_clear, BDRV_REQ_MAY_UNMAP); | |
607 | if (ret < 0) { | |
608 | error_setg_errno(errp, -ret, | |
609 | "Failed to clear the new image's first sector"); | |
610 | return ret; | |
611 | } | |
612 | } | |
613 | ||
614 | return 0; | |
615 | } | |
616 | ||
5a5e7f8c ML |
617 | /** |
618 | * Simple implementation of bdrv_co_create_opts for protocol drivers | |
619 | * which only support creation via opening a file | |
620 | * (usually existing raw storage device) | |
621 | */ | |
622 | int coroutine_fn bdrv_co_create_opts_simple(BlockDriver *drv, | |
623 | const char *filename, | |
624 | QemuOpts *opts, | |
625 | Error **errp) | |
fd17146c HR |
626 | { |
627 | BlockBackend *blk; | |
eeea1faa | 628 | QDict *options; |
fd17146c HR |
629 | int64_t size = 0; |
630 | char *buf = NULL; | |
631 | PreallocMode prealloc; | |
632 | Error *local_err = NULL; | |
633 | int ret; | |
634 | ||
635 | size = qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0); | |
636 | buf = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC); | |
637 | prealloc = qapi_enum_parse(&PreallocMode_lookup, buf, | |
638 | PREALLOC_MODE_OFF, &local_err); | |
639 | g_free(buf); | |
640 | if (local_err) { | |
641 | error_propagate(errp, local_err); | |
642 | return -EINVAL; | |
643 | } | |
644 | ||
645 | if (prealloc != PREALLOC_MODE_OFF) { | |
646 | error_setg(errp, "Unsupported preallocation mode '%s'", | |
647 | PreallocMode_str(prealloc)); | |
648 | return -ENOTSUP; | |
649 | } | |
650 | ||
eeea1faa | 651 | options = qdict_new(); |
fd17146c HR |
652 | qdict_put_str(options, "driver", drv->format_name); |
653 | ||
654 | blk = blk_new_open(filename, NULL, options, | |
655 | BDRV_O_RDWR | BDRV_O_RESIZE, errp); | |
656 | if (!blk) { | |
657 | error_prepend(errp, "Protocol driver '%s' does not support image " | |
658 | "creation, and opening the image failed: ", | |
659 | drv->format_name); | |
660 | return -EINVAL; | |
661 | } | |
662 | ||
663 | size = create_file_fallback_truncate(blk, size, errp); | |
664 | if (size < 0) { | |
665 | ret = size; | |
666 | goto out; | |
667 | } | |
668 | ||
669 | ret = create_file_fallback_zero_first_sector(blk, size, errp); | |
670 | if (ret < 0) { | |
671 | goto out; | |
672 | } | |
673 | ||
674 | ret = 0; | |
675 | out: | |
676 | blk_unref(blk); | |
677 | return ret; | |
678 | } | |
679 | ||
680 | int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp) | |
681 | { | |
729222af | 682 | QemuOpts *protocol_opts; |
fd17146c | 683 | BlockDriver *drv; |
729222af SG |
684 | QDict *qdict; |
685 | int ret; | |
fd17146c | 686 | |
b65a5e12 | 687 | drv = bdrv_find_protocol(filename, true, errp); |
84a12e66 | 688 | if (drv == NULL) { |
16905d71 | 689 | return -ENOENT; |
84a12e66 CH |
690 | } |
691 | ||
729222af SG |
692 | if (!drv->create_opts) { |
693 | error_setg(errp, "Driver '%s' does not support image creation", | |
694 | drv->format_name); | |
695 | return -ENOTSUP; | |
696 | } | |
697 | ||
698 | /* | |
699 | * 'opts' contains a QemuOptsList with a combination of format and protocol | |
700 | * default values. | |
701 | * | |
702 | * The format properly removes its options, but the default values remain | |
703 | * in 'opts->list'. So if the protocol has options with the same name | |
704 | * (e.g. rbd has 'cluster_size' as qcow2), it will see the default values | |
705 | * of the format, since for overlapping options, the format wins. | |
706 | * | |
707 | * To avoid this issue, lets convert QemuOpts to QDict, in this way we take | |
708 | * only the set options, and then convert it back to QemuOpts, using the | |
709 | * create_opts of the protocol. So the new QemuOpts, will contain only the | |
710 | * protocol defaults. | |
711 | */ | |
712 | qdict = qemu_opts_to_qdict(opts, NULL); | |
713 | protocol_opts = qemu_opts_from_qdict(drv->create_opts, qdict, errp); | |
714 | if (protocol_opts == NULL) { | |
715 | ret = -EINVAL; | |
716 | goto out; | |
717 | } | |
718 | ||
719 | ret = bdrv_create(drv, filename, protocol_opts, errp); | |
720 | out: | |
721 | qemu_opts_del(protocol_opts); | |
722 | qobject_unref(qdict); | |
723 | return ret; | |
84a12e66 CH |
724 | } |
725 | ||
e1d7f8bb DHB |
726 | int coroutine_fn bdrv_co_delete_file(BlockDriverState *bs, Error **errp) |
727 | { | |
728 | Error *local_err = NULL; | |
729 | int ret; | |
730 | ||
731 | assert(bs != NULL); | |
732 | ||
733 | if (!bs->drv) { | |
734 | error_setg(errp, "Block node '%s' is not opened", bs->filename); | |
735 | return -ENOMEDIUM; | |
736 | } | |
737 | ||
738 | if (!bs->drv->bdrv_co_delete_file) { | |
739 | error_setg(errp, "Driver '%s' does not support image deletion", | |
740 | bs->drv->format_name); | |
741 | return -ENOTSUP; | |
742 | } | |
743 | ||
744 | ret = bs->drv->bdrv_co_delete_file(bs, &local_err); | |
745 | if (ret < 0) { | |
746 | error_propagate(errp, local_err); | |
747 | } | |
748 | ||
749 | return ret; | |
750 | } | |
751 | ||
a890f08e ML |
752 | void coroutine_fn bdrv_co_delete_file_noerr(BlockDriverState *bs) |
753 | { | |
754 | Error *local_err = NULL; | |
755 | int ret; | |
756 | ||
757 | if (!bs) { | |
758 | return; | |
759 | } | |
760 | ||
761 | ret = bdrv_co_delete_file(bs, &local_err); | |
762 | /* | |
763 | * ENOTSUP will happen if the block driver doesn't support | |
764 | * the 'bdrv_co_delete_file' interface. This is a predictable | |
765 | * scenario and shouldn't be reported back to the user. | |
766 | */ | |
767 | if (ret == -ENOTSUP) { | |
768 | error_free(local_err); | |
769 | } else if (ret < 0) { | |
770 | error_report_err(local_err); | |
771 | } | |
772 | } | |
773 | ||
892b7de8 ET |
774 | /** |
775 | * Try to get @bs's logical and physical block size. | |
776 | * On success, store them in @bsz struct and return 0. | |
777 | * On failure return -errno. | |
778 | * @bs must not be empty. | |
779 | */ | |
780 | int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz) | |
781 | { | |
782 | BlockDriver *drv = bs->drv; | |
93393e69 | 783 | BlockDriverState *filtered = bdrv_filter_bs(bs); |
892b7de8 ET |
784 | |
785 | if (drv && drv->bdrv_probe_blocksizes) { | |
786 | return drv->bdrv_probe_blocksizes(bs, bsz); | |
93393e69 HR |
787 | } else if (filtered) { |
788 | return bdrv_probe_blocksizes(filtered, bsz); | |
892b7de8 ET |
789 | } |
790 | ||
791 | return -ENOTSUP; | |
792 | } | |
793 | ||
794 | /** | |
795 | * Try to get @bs's geometry (cyls, heads, sectors). | |
796 | * On success, store them in @geo struct and return 0. | |
797 | * On failure return -errno. | |
798 | * @bs must not be empty. | |
799 | */ | |
800 | int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo) | |
801 | { | |
802 | BlockDriver *drv = bs->drv; | |
93393e69 | 803 | BlockDriverState *filtered = bdrv_filter_bs(bs); |
892b7de8 ET |
804 | |
805 | if (drv && drv->bdrv_probe_geometry) { | |
806 | return drv->bdrv_probe_geometry(bs, geo); | |
93393e69 HR |
807 | } else if (filtered) { |
808 | return bdrv_probe_geometry(filtered, geo); | |
892b7de8 ET |
809 | } |
810 | ||
811 | return -ENOTSUP; | |
812 | } | |
813 | ||
eba25057 JM |
814 | /* |
815 | * Create a uniquely-named empty temporary file. | |
816 | * Return 0 upon success, otherwise a negative errno value. | |
817 | */ | |
818 | int get_tmp_filename(char *filename, int size) | |
d5249393 | 819 | { |
eba25057 | 820 | #ifdef _WIN32 |
3b9f94e1 | 821 | char temp_dir[MAX_PATH]; |
eba25057 JM |
822 | /* GetTempFileName requires that its output buffer (4th param) |
823 | have length MAX_PATH or greater. */ | |
824 | assert(size >= MAX_PATH); | |
825 | return (GetTempPath(MAX_PATH, temp_dir) | |
826 | && GetTempFileName(temp_dir, "qem", 0, filename) | |
827 | ? 0 : -GetLastError()); | |
d5249393 | 828 | #else |
67b915a5 | 829 | int fd; |
7ccfb2eb | 830 | const char *tmpdir; |
0badc1ee | 831 | tmpdir = getenv("TMPDIR"); |
69bef793 AS |
832 | if (!tmpdir) { |
833 | tmpdir = "/var/tmp"; | |
834 | } | |
eba25057 JM |
835 | if (snprintf(filename, size, "%s/vl.XXXXXX", tmpdir) >= size) { |
836 | return -EOVERFLOW; | |
837 | } | |
ea2384d3 | 838 | fd = mkstemp(filename); |
fe235a06 DH |
839 | if (fd < 0) { |
840 | return -errno; | |
841 | } | |
842 | if (close(fd) != 0) { | |
843 | unlink(filename); | |
eba25057 JM |
844 | return -errno; |
845 | } | |
846 | return 0; | |
d5249393 | 847 | #endif |
eba25057 | 848 | } |
fc01f7e7 | 849 | |
84a12e66 CH |
850 | /* |
851 | * Detect host devices. By convention, /dev/cdrom[N] is always | |
852 | * recognized as a host CDROM. | |
853 | */ | |
854 | static BlockDriver *find_hdev_driver(const char *filename) | |
855 | { | |
856 | int score_max = 0, score; | |
857 | BlockDriver *drv = NULL, *d; | |
858 | ||
859 | QLIST_FOREACH(d, &bdrv_drivers, list) { | |
860 | if (d->bdrv_probe_device) { | |
861 | score = d->bdrv_probe_device(filename); | |
862 | if (score > score_max) { | |
863 | score_max = score; | |
864 | drv = d; | |
865 | } | |
866 | } | |
867 | } | |
868 | ||
869 | return drv; | |
870 | } | |
871 | ||
88d88798 MM |
872 | static BlockDriver *bdrv_do_find_protocol(const char *protocol) |
873 | { | |
874 | BlockDriver *drv1; | |
875 | ||
876 | QLIST_FOREACH(drv1, &bdrv_drivers, list) { | |
877 | if (drv1->protocol_name && !strcmp(drv1->protocol_name, protocol)) { | |
878 | return drv1; | |
879 | } | |
880 | } | |
881 | ||
882 | return NULL; | |
883 | } | |
884 | ||
98289620 | 885 | BlockDriver *bdrv_find_protocol(const char *filename, |
b65a5e12 HR |
886 | bool allow_protocol_prefix, |
887 | Error **errp) | |
83f64091 FB |
888 | { |
889 | BlockDriver *drv1; | |
890 | char protocol[128]; | |
1cec71e3 | 891 | int len; |
83f64091 | 892 | const char *p; |
88d88798 | 893 | int i; |
19cb3738 | 894 | |
66f82cee KW |
895 | /* TODO Drivers without bdrv_file_open must be specified explicitly */ |
896 | ||
39508e7a CH |
897 | /* |
898 | * XXX(hch): we really should not let host device detection | |
899 | * override an explicit protocol specification, but moving this | |
900 | * later breaks access to device names with colons in them. | |
901 | * Thanks to the brain-dead persistent naming schemes on udev- | |
902 | * based Linux systems those actually are quite common. | |
903 | */ | |
904 | drv1 = find_hdev_driver(filename); | |
905 | if (drv1) { | |
906 | return drv1; | |
907 | } | |
908 | ||
98289620 | 909 | if (!path_has_protocol(filename) || !allow_protocol_prefix) { |
ef810437 | 910 | return &bdrv_file; |
84a12e66 | 911 | } |
98289620 | 912 | |
9e0b22f4 SH |
913 | p = strchr(filename, ':'); |
914 | assert(p != NULL); | |
1cec71e3 AL |
915 | len = p - filename; |
916 | if (len > sizeof(protocol) - 1) | |
917 | len = sizeof(protocol) - 1; | |
918 | memcpy(protocol, filename, len); | |
919 | protocol[len] = '\0'; | |
88d88798 MM |
920 | |
921 | drv1 = bdrv_do_find_protocol(protocol); | |
922 | if (drv1) { | |
923 | return drv1; | |
924 | } | |
925 | ||
926 | for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); ++i) { | |
927 | if (block_driver_modules[i].protocol_name && | |
928 | !strcmp(block_driver_modules[i].protocol_name, protocol)) { | |
929 | block_module_load_one(block_driver_modules[i].library_name); | |
930 | break; | |
8a22f02a | 931 | } |
83f64091 | 932 | } |
b65a5e12 | 933 | |
88d88798 MM |
934 | drv1 = bdrv_do_find_protocol(protocol); |
935 | if (!drv1) { | |
936 | error_setg(errp, "Unknown protocol '%s'", protocol); | |
937 | } | |
938 | return drv1; | |
83f64091 FB |
939 | } |
940 | ||
c6684249 MA |
941 | /* |
942 | * Guess image format by probing its contents. | |
943 | * This is not a good idea when your image is raw (CVE-2008-2004), but | |
944 | * we do it anyway for backward compatibility. | |
945 | * | |
946 | * @buf contains the image's first @buf_size bytes. | |
7cddd372 KW |
947 | * @buf_size is the buffer size in bytes (generally BLOCK_PROBE_BUF_SIZE, |
948 | * but can be smaller if the image file is smaller) | |
c6684249 MA |
949 | * @filename is its filename. |
950 | * | |
951 | * For all block drivers, call the bdrv_probe() method to get its | |
952 | * probing score. | |
953 | * Return the first block driver with the highest probing score. | |
954 | */ | |
38f3ef57 KW |
955 | BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, |
956 | const char *filename) | |
c6684249 MA |
957 | { |
958 | int score_max = 0, score; | |
959 | BlockDriver *drv = NULL, *d; | |
960 | ||
961 | QLIST_FOREACH(d, &bdrv_drivers, list) { | |
962 | if (d->bdrv_probe) { | |
963 | score = d->bdrv_probe(buf, buf_size, filename); | |
964 | if (score > score_max) { | |
965 | score_max = score; | |
966 | drv = d; | |
967 | } | |
968 | } | |
969 | } | |
970 | ||
971 | return drv; | |
972 | } | |
973 | ||
5696c6e3 | 974 | static int find_image_format(BlockBackend *file, const char *filename, |
34b5d2c6 | 975 | BlockDriver **pdrv, Error **errp) |
f3a5d3f8 | 976 | { |
c6684249 | 977 | BlockDriver *drv; |
7cddd372 | 978 | uint8_t buf[BLOCK_PROBE_BUF_SIZE]; |
f500a6d3 | 979 | int ret = 0; |
f8ea0b00 | 980 | |
08a00559 | 981 | /* Return the raw BlockDriver * to scsi-generic devices or empty drives */ |
5696c6e3 | 982 | if (blk_is_sg(file) || !blk_is_inserted(file) || blk_getlength(file) == 0) { |
ef810437 | 983 | *pdrv = &bdrv_raw; |
c98ac35d | 984 | return ret; |
1a396859 | 985 | } |
f8ea0b00 | 986 | |
5696c6e3 | 987 | ret = blk_pread(file, 0, buf, sizeof(buf)); |
83f64091 | 988 | if (ret < 0) { |
34b5d2c6 HR |
989 | error_setg_errno(errp, -ret, "Could not read image for determining its " |
990 | "format"); | |
c98ac35d SW |
991 | *pdrv = NULL; |
992 | return ret; | |
83f64091 FB |
993 | } |
994 | ||
c6684249 | 995 | drv = bdrv_probe_all(buf, ret, filename); |
c98ac35d | 996 | if (!drv) { |
34b5d2c6 HR |
997 | error_setg(errp, "Could not determine image format: No compatible " |
998 | "driver found"); | |
c98ac35d SW |
999 | ret = -ENOENT; |
1000 | } | |
1001 | *pdrv = drv; | |
1002 | return ret; | |
ea2384d3 FB |
1003 | } |
1004 | ||
51762288 SH |
1005 | /** |
1006 | * Set the current 'total_sectors' value | |
65a9bb25 | 1007 | * Return 0 on success, -errno on error. |
51762288 | 1008 | */ |
3d9f2d2a | 1009 | int refresh_total_sectors(BlockDriverState *bs, int64_t hint) |
51762288 SH |
1010 | { |
1011 | BlockDriver *drv = bs->drv; | |
1012 | ||
d470ad42 HR |
1013 | if (!drv) { |
1014 | return -ENOMEDIUM; | |
1015 | } | |
1016 | ||
396759ad | 1017 | /* Do not attempt drv->bdrv_getlength() on scsi-generic devices */ |
b192af8a | 1018 | if (bdrv_is_sg(bs)) |
396759ad NB |
1019 | return 0; |
1020 | ||
51762288 SH |
1021 | /* query actual device if possible, otherwise just trust the hint */ |
1022 | if (drv->bdrv_getlength) { | |
1023 | int64_t length = drv->bdrv_getlength(bs); | |
1024 | if (length < 0) { | |
1025 | return length; | |
1026 | } | |
7e382003 | 1027 | hint = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE); |
51762288 SH |
1028 | } |
1029 | ||
1030 | bs->total_sectors = hint; | |
8b117001 VSO |
1031 | |
1032 | if (bs->total_sectors * BDRV_SECTOR_SIZE > BDRV_MAX_LENGTH) { | |
1033 | return -EFBIG; | |
1034 | } | |
1035 | ||
51762288 SH |
1036 | return 0; |
1037 | } | |
1038 | ||
cddff5ba KW |
1039 | /** |
1040 | * Combines a QDict of new block driver @options with any missing options taken | |
1041 | * from @old_options, so that leaving out an option defaults to its old value. | |
1042 | */ | |
1043 | static void bdrv_join_options(BlockDriverState *bs, QDict *options, | |
1044 | QDict *old_options) | |
1045 | { | |
1046 | if (bs->drv && bs->drv->bdrv_join_options) { | |
1047 | bs->drv->bdrv_join_options(options, old_options); | |
1048 | } else { | |
1049 | qdict_join(options, old_options, false); | |
1050 | } | |
1051 | } | |
1052 | ||
543770bd AG |
1053 | static BlockdevDetectZeroesOptions bdrv_parse_detect_zeroes(QemuOpts *opts, |
1054 | int open_flags, | |
1055 | Error **errp) | |
1056 | { | |
1057 | Error *local_err = NULL; | |
1058 | char *value = qemu_opt_get_del(opts, "detect-zeroes"); | |
1059 | BlockdevDetectZeroesOptions detect_zeroes = | |
1060 | qapi_enum_parse(&BlockdevDetectZeroesOptions_lookup, value, | |
1061 | BLOCKDEV_DETECT_ZEROES_OPTIONS_OFF, &local_err); | |
1062 | g_free(value); | |
1063 | if (local_err) { | |
1064 | error_propagate(errp, local_err); | |
1065 | return detect_zeroes; | |
1066 | } | |
1067 | ||
1068 | if (detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP && | |
1069 | !(open_flags & BDRV_O_UNMAP)) | |
1070 | { | |
1071 | error_setg(errp, "setting detect-zeroes to unmap is not allowed " | |
1072 | "without setting discard operation to unmap"); | |
1073 | } | |
1074 | ||
1075 | return detect_zeroes; | |
1076 | } | |
1077 | ||
f80f2673 AM |
1078 | /** |
1079 | * Set open flags for aio engine | |
1080 | * | |
1081 | * Return 0 on success, -1 if the engine specified is invalid | |
1082 | */ | |
1083 | int bdrv_parse_aio(const char *mode, int *flags) | |
1084 | { | |
1085 | if (!strcmp(mode, "threads")) { | |
1086 | /* do nothing, default */ | |
1087 | } else if (!strcmp(mode, "native")) { | |
1088 | *flags |= BDRV_O_NATIVE_AIO; | |
1089 | #ifdef CONFIG_LINUX_IO_URING | |
1090 | } else if (!strcmp(mode, "io_uring")) { | |
1091 | *flags |= BDRV_O_IO_URING; | |
1092 | #endif | |
1093 | } else { | |
1094 | return -1; | |
1095 | } | |
1096 | ||
1097 | return 0; | |
1098 | } | |
1099 | ||
9e8f1835 PB |
1100 | /** |
1101 | * Set open flags for a given discard mode | |
1102 | * | |
1103 | * Return 0 on success, -1 if the discard mode was invalid. | |
1104 | */ | |
1105 | int bdrv_parse_discard_flags(const char *mode, int *flags) | |
1106 | { | |
1107 | *flags &= ~BDRV_O_UNMAP; | |
1108 | ||
1109 | if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) { | |
1110 | /* do nothing */ | |
1111 | } else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) { | |
1112 | *flags |= BDRV_O_UNMAP; | |
1113 | } else { | |
1114 | return -1; | |
1115 | } | |
1116 | ||
1117 | return 0; | |
1118 | } | |
1119 | ||
c3993cdc SH |
1120 | /** |
1121 | * Set open flags for a given cache mode | |
1122 | * | |
1123 | * Return 0 on success, -1 if the cache mode was invalid. | |
1124 | */ | |
53e8ae01 | 1125 | int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough) |
c3993cdc SH |
1126 | { |
1127 | *flags &= ~BDRV_O_CACHE_MASK; | |
1128 | ||
1129 | if (!strcmp(mode, "off") || !strcmp(mode, "none")) { | |
53e8ae01 KW |
1130 | *writethrough = false; |
1131 | *flags |= BDRV_O_NOCACHE; | |
92196b2f | 1132 | } else if (!strcmp(mode, "directsync")) { |
53e8ae01 | 1133 | *writethrough = true; |
92196b2f | 1134 | *flags |= BDRV_O_NOCACHE; |
c3993cdc | 1135 | } else if (!strcmp(mode, "writeback")) { |
53e8ae01 | 1136 | *writethrough = false; |
c3993cdc | 1137 | } else if (!strcmp(mode, "unsafe")) { |
53e8ae01 | 1138 | *writethrough = false; |
c3993cdc SH |
1139 | *flags |= BDRV_O_NO_FLUSH; |
1140 | } else if (!strcmp(mode, "writethrough")) { | |
53e8ae01 | 1141 | *writethrough = true; |
c3993cdc SH |
1142 | } else { |
1143 | return -1; | |
1144 | } | |
1145 | ||
1146 | return 0; | |
1147 | } | |
1148 | ||
b5411555 KW |
1149 | static char *bdrv_child_get_parent_desc(BdrvChild *c) |
1150 | { | |
1151 | BlockDriverState *parent = c->opaque; | |
1152 | return g_strdup(bdrv_get_device_or_node_name(parent)); | |
1153 | } | |
1154 | ||
20018e12 KW |
1155 | static void bdrv_child_cb_drained_begin(BdrvChild *child) |
1156 | { | |
1157 | BlockDriverState *bs = child->opaque; | |
6cd5c9d7 | 1158 | bdrv_do_drained_begin_quiesce(bs, NULL, false); |
20018e12 KW |
1159 | } |
1160 | ||
89bd0305 KW |
1161 | static bool bdrv_child_cb_drained_poll(BdrvChild *child) |
1162 | { | |
1163 | BlockDriverState *bs = child->opaque; | |
6cd5c9d7 | 1164 | return bdrv_drain_poll(bs, false, NULL, false); |
89bd0305 KW |
1165 | } |
1166 | ||
e037c09c HR |
1167 | static void bdrv_child_cb_drained_end(BdrvChild *child, |
1168 | int *drained_end_counter) | |
20018e12 KW |
1169 | { |
1170 | BlockDriverState *bs = child->opaque; | |
e037c09c | 1171 | bdrv_drained_end_no_poll(bs, drained_end_counter); |
20018e12 KW |
1172 | } |
1173 | ||
38701b6a KW |
1174 | static int bdrv_child_cb_inactivate(BdrvChild *child) |
1175 | { | |
1176 | BlockDriverState *bs = child->opaque; | |
1177 | assert(bs->open_flags & BDRV_O_INACTIVE); | |
1178 | return 0; | |
1179 | } | |
1180 | ||
5d231849 KW |
1181 | static bool bdrv_child_cb_can_set_aio_ctx(BdrvChild *child, AioContext *ctx, |
1182 | GSList **ignore, Error **errp) | |
1183 | { | |
1184 | BlockDriverState *bs = child->opaque; | |
1185 | return bdrv_can_set_aio_context(bs, ctx, ignore, errp); | |
1186 | } | |
1187 | ||
53a7d041 KW |
1188 | static void bdrv_child_cb_set_aio_ctx(BdrvChild *child, AioContext *ctx, |
1189 | GSList **ignore) | |
1190 | { | |
1191 | BlockDriverState *bs = child->opaque; | |
1192 | return bdrv_set_aio_context_ignore(bs, ctx, ignore); | |
1193 | } | |
1194 | ||
b1e6fc08 | 1195 | /* |
73176bee KW |
1196 | * Returns the options and flags that a temporary snapshot should get, based on |
1197 | * the originally requested flags (the originally requested image will have | |
1198 | * flags like a backing file) | |
b1e6fc08 | 1199 | */ |
73176bee KW |
1200 | static void bdrv_temp_snapshot_options(int *child_flags, QDict *child_options, |
1201 | int parent_flags, QDict *parent_options) | |
b1e6fc08 | 1202 | { |
73176bee KW |
1203 | *child_flags = (parent_flags & ~BDRV_O_SNAPSHOT) | BDRV_O_TEMPORARY; |
1204 | ||
1205 | /* For temporary files, unconditional cache=unsafe is fine */ | |
73176bee KW |
1206 | qdict_set_default_str(child_options, BDRV_OPT_CACHE_DIRECT, "off"); |
1207 | qdict_set_default_str(child_options, BDRV_OPT_CACHE_NO_FLUSH, "on"); | |
41869044 | 1208 | |
3f48686f | 1209 | /* Copy the read-only and discard options from the parent */ |
f87a0e29 | 1210 | qdict_copy_default(child_options, parent_options, BDRV_OPT_READ_ONLY); |
3f48686f | 1211 | qdict_copy_default(child_options, parent_options, BDRV_OPT_DISCARD); |
f87a0e29 | 1212 | |
41869044 KW |
1213 | /* aio=native doesn't work for cache.direct=off, so disable it for the |
1214 | * temporary snapshot */ | |
1215 | *child_flags &= ~BDRV_O_NATIVE_AIO; | |
b1e6fc08 KW |
1216 | } |
1217 | ||
db95dbba KW |
1218 | static void bdrv_backing_attach(BdrvChild *c) |
1219 | { | |
1220 | BlockDriverState *parent = c->opaque; | |
1221 | BlockDriverState *backing_hd = c->bs; | |
1222 | ||
1223 | assert(!parent->backing_blocker); | |
1224 | error_setg(&parent->backing_blocker, | |
1225 | "node is used as backing hd of '%s'", | |
1226 | bdrv_get_device_or_node_name(parent)); | |
1227 | ||
f30c66ba HR |
1228 | bdrv_refresh_filename(backing_hd); |
1229 | ||
db95dbba | 1230 | parent->open_flags &= ~BDRV_O_NO_BACKING; |
db95dbba KW |
1231 | |
1232 | bdrv_op_block_all(backing_hd, parent->backing_blocker); | |
1233 | /* Otherwise we won't be able to commit or stream */ | |
1234 | bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_COMMIT_TARGET, | |
1235 | parent->backing_blocker); | |
1236 | bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_STREAM, | |
1237 | parent->backing_blocker); | |
1238 | /* | |
1239 | * We do backup in 3 ways: | |
1240 | * 1. drive backup | |
1241 | * The target bs is new opened, and the source is top BDS | |
1242 | * 2. blockdev backup | |
1243 | * Both the source and the target are top BDSes. | |
1244 | * 3. internal backup(used for block replication) | |
1245 | * Both the source and the target are backing file | |
1246 | * | |
1247 | * In case 1 and 2, neither the source nor the target is the backing file. | |
1248 | * In case 3, we will block the top BDS, so there is only one block job | |
1249 | * for the top BDS and its backing chain. | |
1250 | */ | |
1251 | bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_SOURCE, | |
1252 | parent->backing_blocker); | |
1253 | bdrv_op_unblock(backing_hd, BLOCK_OP_TYPE_BACKUP_TARGET, | |
1254 | parent->backing_blocker); | |
ca2f1234 | 1255 | } |
d736f119 | 1256 | |
db95dbba KW |
1257 | static void bdrv_backing_detach(BdrvChild *c) |
1258 | { | |
1259 | BlockDriverState *parent = c->opaque; | |
1260 | ||
1261 | assert(parent->backing_blocker); | |
1262 | bdrv_op_unblock_all(c->bs, parent->backing_blocker); | |
1263 | error_free(parent->backing_blocker); | |
1264 | parent->backing_blocker = NULL; | |
48e08288 | 1265 | } |
d736f119 | 1266 | |
6858eba0 KW |
1267 | static int bdrv_backing_update_filename(BdrvChild *c, BlockDriverState *base, |
1268 | const char *filename, Error **errp) | |
1269 | { | |
1270 | BlockDriverState *parent = c->opaque; | |
e94d3dba | 1271 | bool read_only = bdrv_is_read_only(parent); |
6858eba0 KW |
1272 | int ret; |
1273 | ||
e94d3dba AG |
1274 | if (read_only) { |
1275 | ret = bdrv_reopen_set_read_only(parent, false, errp); | |
61f09cea KW |
1276 | if (ret < 0) { |
1277 | return ret; | |
1278 | } | |
1279 | } | |
1280 | ||
6858eba0 | 1281 | ret = bdrv_change_backing_file(parent, filename, |
e54ee1b3 EB |
1282 | base->drv ? base->drv->format_name : "", |
1283 | false); | |
6858eba0 | 1284 | if (ret < 0) { |
64730694 | 1285 | error_setg_errno(errp, -ret, "Could not update backing file link"); |
6858eba0 KW |
1286 | } |
1287 | ||
e94d3dba AG |
1288 | if (read_only) { |
1289 | bdrv_reopen_set_read_only(parent, true, NULL); | |
61f09cea KW |
1290 | } |
1291 | ||
6858eba0 KW |
1292 | return ret; |
1293 | } | |
1294 | ||
fae8bd39 HR |
1295 | /* |
1296 | * Returns the options and flags that a generic child of a BDS should | |
1297 | * get, based on the given options and flags for the parent BDS. | |
1298 | */ | |
00ff7ffd HR |
1299 | static void bdrv_inherited_options(BdrvChildRole role, bool parent_is_format, |
1300 | int *child_flags, QDict *child_options, | |
1301 | int parent_flags, QDict *parent_options) | |
fae8bd39 HR |
1302 | { |
1303 | int flags = parent_flags; | |
1304 | ||
1305 | /* | |
1306 | * First, decide whether to set, clear, or leave BDRV_O_PROTOCOL. | |
1307 | * Generally, the question to answer is: Should this child be | |
1308 | * format-probed by default? | |
1309 | */ | |
1310 | ||
1311 | /* | |
1312 | * Pure and non-filtered data children of non-format nodes should | |
1313 | * be probed by default (even when the node itself has BDRV_O_PROTOCOL | |
1314 | * set). This only affects a very limited set of drivers (namely | |
1315 | * quorum and blkverify when this comment was written). | |
1316 | * Force-clear BDRV_O_PROTOCOL then. | |
1317 | */ | |
1318 | if (!parent_is_format && | |
1319 | (role & BDRV_CHILD_DATA) && | |
1320 | !(role & (BDRV_CHILD_METADATA | BDRV_CHILD_FILTERED))) | |
1321 | { | |
1322 | flags &= ~BDRV_O_PROTOCOL; | |
1323 | } | |
1324 | ||
1325 | /* | |
1326 | * All children of format nodes (except for COW children) and all | |
1327 | * metadata children in general should never be format-probed. | |
1328 | * Force-set BDRV_O_PROTOCOL then. | |
1329 | */ | |
1330 | if ((parent_is_format && !(role & BDRV_CHILD_COW)) || | |
1331 | (role & BDRV_CHILD_METADATA)) | |
1332 | { | |
1333 | flags |= BDRV_O_PROTOCOL; | |
1334 | } | |
1335 | ||
1336 | /* | |
1337 | * If the cache mode isn't explicitly set, inherit direct and no-flush from | |
1338 | * the parent. | |
1339 | */ | |
1340 | qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_DIRECT); | |
1341 | qdict_copy_default(child_options, parent_options, BDRV_OPT_CACHE_NO_FLUSH); | |
1342 | qdict_copy_default(child_options, parent_options, BDRV_OPT_FORCE_SHARE); | |
1343 | ||
1344 | if (role & BDRV_CHILD_COW) { | |
1345 | /* backing files are opened read-only by default */ | |
1346 | qdict_set_default_str(child_options, BDRV_OPT_READ_ONLY, "on"); | |
1347 | qdict_set_default_str(child_options, BDRV_OPT_AUTO_READ_ONLY, "off"); | |
1348 | } else { | |
1349 | /* Inherit the read-only option from the parent if it's not set */ | |
1350 | qdict_copy_default(child_options, parent_options, BDRV_OPT_READ_ONLY); | |
1351 | qdict_copy_default(child_options, parent_options, | |
1352 | BDRV_OPT_AUTO_READ_ONLY); | |
1353 | } | |
1354 | ||
1355 | /* | |
1356 | * bdrv_co_pdiscard() respects unmap policy for the parent, so we | |
1357 | * can default to enable it on lower layers regardless of the | |
1358 | * parent option. | |
1359 | */ | |
1360 | qdict_set_default_str(child_options, BDRV_OPT_DISCARD, "unmap"); | |
1361 | ||
1362 | /* Clear flags that only apply to the top layer */ | |
1363 | flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_COPY_ON_READ); | |
1364 | ||
1365 | if (role & BDRV_CHILD_METADATA) { | |
1366 | flags &= ~BDRV_O_NO_IO; | |
1367 | } | |
1368 | if (role & BDRV_CHILD_COW) { | |
1369 | flags &= ~BDRV_O_TEMPORARY; | |
1370 | } | |
1371 | ||
1372 | *child_flags = flags; | |
1373 | } | |
1374 | ||
ca2f1234 HR |
1375 | static void bdrv_child_cb_attach(BdrvChild *child) |
1376 | { | |
1377 | BlockDriverState *bs = child->opaque; | |
1378 | ||
1379 | if (child->role & BDRV_CHILD_COW) { | |
1380 | bdrv_backing_attach(child); | |
1381 | } | |
1382 | ||
1383 | bdrv_apply_subtree_drain(child, bs); | |
1384 | } | |
1385 | ||
48e08288 HR |
1386 | static void bdrv_child_cb_detach(BdrvChild *child) |
1387 | { | |
1388 | BlockDriverState *bs = child->opaque; | |
1389 | ||
1390 | if (child->role & BDRV_CHILD_COW) { | |
1391 | bdrv_backing_detach(child); | |
1392 | } | |
1393 | ||
1394 | bdrv_unapply_subtree_drain(child, bs); | |
1395 | } | |
1396 | ||
43483550 HR |
1397 | static int bdrv_child_cb_update_filename(BdrvChild *c, BlockDriverState *base, |
1398 | const char *filename, Error **errp) | |
1399 | { | |
1400 | if (c->role & BDRV_CHILD_COW) { | |
1401 | return bdrv_backing_update_filename(c, base, filename, errp); | |
1402 | } | |
1403 | return 0; | |
1404 | } | |
1405 | ||
3ca1f322 VSO |
1406 | static AioContext *bdrv_child_cb_get_parent_aio_context(BdrvChild *c) |
1407 | { | |
1408 | BlockDriverState *bs = c->opaque; | |
1409 | ||
1410 | return bdrv_get_aio_context(bs); | |
1411 | } | |
1412 | ||
43483550 HR |
1413 | const BdrvChildClass child_of_bds = { |
1414 | .parent_is_bds = true, | |
1415 | .get_parent_desc = bdrv_child_get_parent_desc, | |
1416 | .inherit_options = bdrv_inherited_options, | |
1417 | .drained_begin = bdrv_child_cb_drained_begin, | |
1418 | .drained_poll = bdrv_child_cb_drained_poll, | |
1419 | .drained_end = bdrv_child_cb_drained_end, | |
1420 | .attach = bdrv_child_cb_attach, | |
1421 | .detach = bdrv_child_cb_detach, | |
1422 | .inactivate = bdrv_child_cb_inactivate, | |
1423 | .can_set_aio_ctx = bdrv_child_cb_can_set_aio_ctx, | |
1424 | .set_aio_ctx = bdrv_child_cb_set_aio_ctx, | |
1425 | .update_filename = bdrv_child_cb_update_filename, | |
3ca1f322 | 1426 | .get_parent_aio_context = bdrv_child_cb_get_parent_aio_context, |
43483550 HR |
1427 | }; |
1428 | ||
3ca1f322 VSO |
1429 | AioContext *bdrv_child_get_parent_aio_context(BdrvChild *c) |
1430 | { | |
1431 | return c->klass->get_parent_aio_context(c); | |
1432 | } | |
1433 | ||
7b272452 KW |
1434 | static int bdrv_open_flags(BlockDriverState *bs, int flags) |
1435 | { | |
61de4c68 | 1436 | int open_flags = flags; |
7b272452 KW |
1437 | |
1438 | /* | |
1439 | * Clear flags that are internal to the block layer before opening the | |
1440 | * image. | |
1441 | */ | |
20cca275 | 1442 | open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING | BDRV_O_PROTOCOL); |
7b272452 | 1443 | |
7b272452 KW |
1444 | return open_flags; |
1445 | } | |
1446 | ||
91a097e7 KW |
1447 | static void update_flags_from_options(int *flags, QemuOpts *opts) |
1448 | { | |
2a3d4331 | 1449 | *flags &= ~(BDRV_O_CACHE_MASK | BDRV_O_RDWR | BDRV_O_AUTO_RDONLY); |
91a097e7 | 1450 | |
57f9db9a | 1451 | if (qemu_opt_get_bool_del(opts, BDRV_OPT_CACHE_NO_FLUSH, false)) { |
91a097e7 KW |
1452 | *flags |= BDRV_O_NO_FLUSH; |
1453 | } | |
1454 | ||
57f9db9a | 1455 | if (qemu_opt_get_bool_del(opts, BDRV_OPT_CACHE_DIRECT, false)) { |
91a097e7 KW |
1456 | *flags |= BDRV_O_NOCACHE; |
1457 | } | |
f87a0e29 | 1458 | |
57f9db9a | 1459 | if (!qemu_opt_get_bool_del(opts, BDRV_OPT_READ_ONLY, false)) { |
f87a0e29 AG |
1460 | *flags |= BDRV_O_RDWR; |
1461 | } | |
1462 | ||
e35bdc12 KW |
1463 | if (qemu_opt_get_bool_del(opts, BDRV_OPT_AUTO_READ_ONLY, false)) { |
1464 | *flags |= BDRV_O_AUTO_RDONLY; | |
1465 | } | |
91a097e7 KW |
1466 | } |
1467 | ||
1468 | static void update_options_from_flags(QDict *options, int flags) | |
1469 | { | |
91a097e7 | 1470 | if (!qdict_haskey(options, BDRV_OPT_CACHE_DIRECT)) { |
46f5ac20 | 1471 | qdict_put_bool(options, BDRV_OPT_CACHE_DIRECT, flags & BDRV_O_NOCACHE); |
91a097e7 KW |
1472 | } |
1473 | if (!qdict_haskey(options, BDRV_OPT_CACHE_NO_FLUSH)) { | |
46f5ac20 EB |
1474 | qdict_put_bool(options, BDRV_OPT_CACHE_NO_FLUSH, |
1475 | flags & BDRV_O_NO_FLUSH); | |
91a097e7 | 1476 | } |
f87a0e29 | 1477 | if (!qdict_haskey(options, BDRV_OPT_READ_ONLY)) { |
46f5ac20 | 1478 | qdict_put_bool(options, BDRV_OPT_READ_ONLY, !(flags & BDRV_O_RDWR)); |
f87a0e29 | 1479 | } |
e35bdc12 KW |
1480 | if (!qdict_haskey(options, BDRV_OPT_AUTO_READ_ONLY)) { |
1481 | qdict_put_bool(options, BDRV_OPT_AUTO_READ_ONLY, | |
1482 | flags & BDRV_O_AUTO_RDONLY); | |
1483 | } | |
91a097e7 KW |
1484 | } |
1485 | ||
636ea370 KW |
1486 | static void bdrv_assign_node_name(BlockDriverState *bs, |
1487 | const char *node_name, | |
1488 | Error **errp) | |
6913c0c2 | 1489 | { |
15489c76 | 1490 | char *gen_node_name = NULL; |
6913c0c2 | 1491 | |
15489c76 JC |
1492 | if (!node_name) { |
1493 | node_name = gen_node_name = id_generate(ID_BLOCK); | |
1494 | } else if (!id_wellformed(node_name)) { | |
1495 | /* | |
1496 | * Check for empty string or invalid characters, but not if it is | |
1497 | * generated (generated names use characters not available to the user) | |
1498 | */ | |
785ec4b1 | 1499 | error_setg(errp, "Invalid node-name: '%s'", node_name); |
636ea370 | 1500 | return; |
6913c0c2 BC |
1501 | } |
1502 | ||
0c5e94ee | 1503 | /* takes care of avoiding namespaces collisions */ |
7f06d47e | 1504 | if (blk_by_name(node_name)) { |
0c5e94ee BC |
1505 | error_setg(errp, "node-name=%s is conflicting with a device id", |
1506 | node_name); | |
15489c76 | 1507 | goto out; |
0c5e94ee BC |
1508 | } |
1509 | ||
6913c0c2 BC |
1510 | /* takes care of avoiding duplicates node names */ |
1511 | if (bdrv_find_node(node_name)) { | |
785ec4b1 | 1512 | error_setg(errp, "Duplicate nodes with node-name='%s'", node_name); |
15489c76 | 1513 | goto out; |
6913c0c2 BC |
1514 | } |
1515 | ||
824808dd KW |
1516 | /* Make sure that the node name isn't truncated */ |
1517 | if (strlen(node_name) >= sizeof(bs->node_name)) { | |
1518 | error_setg(errp, "Node name too long"); | |
1519 | goto out; | |
1520 | } | |
1521 | ||
6913c0c2 BC |
1522 | /* copy node name into the bs and insert it into the graph list */ |
1523 | pstrcpy(bs->node_name, sizeof(bs->node_name), node_name); | |
1524 | QTAILQ_INSERT_TAIL(&graph_bdrv_states, bs, node_list); | |
15489c76 JC |
1525 | out: |
1526 | g_free(gen_node_name); | |
6913c0c2 BC |
1527 | } |
1528 | ||
01a56501 KW |
1529 | static int bdrv_open_driver(BlockDriverState *bs, BlockDriver *drv, |
1530 | const char *node_name, QDict *options, | |
1531 | int open_flags, Error **errp) | |
1532 | { | |
1533 | Error *local_err = NULL; | |
0f12264e | 1534 | int i, ret; |
01a56501 KW |
1535 | |
1536 | bdrv_assign_node_name(bs, node_name, &local_err); | |
1537 | if (local_err) { | |
1538 | error_propagate(errp, local_err); | |
1539 | return -EINVAL; | |
1540 | } | |
1541 | ||
1542 | bs->drv = drv; | |
680c7f96 | 1543 | bs->read_only = !(bs->open_flags & BDRV_O_RDWR); |
01a56501 KW |
1544 | bs->opaque = g_malloc0(drv->instance_size); |
1545 | ||
1546 | if (drv->bdrv_file_open) { | |
1547 | assert(!drv->bdrv_needs_filename || bs->filename[0]); | |
1548 | ret = drv->bdrv_file_open(bs, options, open_flags, &local_err); | |
680c7f96 | 1549 | } else if (drv->bdrv_open) { |
01a56501 | 1550 | ret = drv->bdrv_open(bs, options, open_flags, &local_err); |
680c7f96 KW |
1551 | } else { |
1552 | ret = 0; | |
01a56501 KW |
1553 | } |
1554 | ||
1555 | if (ret < 0) { | |
1556 | if (local_err) { | |
1557 | error_propagate(errp, local_err); | |
1558 | } else if (bs->filename[0]) { | |
1559 | error_setg_errno(errp, -ret, "Could not open '%s'", bs->filename); | |
1560 | } else { | |
1561 | error_setg_errno(errp, -ret, "Could not open image"); | |
1562 | } | |
180ca19a | 1563 | goto open_failed; |
01a56501 KW |
1564 | } |
1565 | ||
1566 | ret = refresh_total_sectors(bs, bs->total_sectors); | |
1567 | if (ret < 0) { | |
1568 | error_setg_errno(errp, -ret, "Could not refresh total sector count"); | |
180ca19a | 1569 | return ret; |
01a56501 KW |
1570 | } |
1571 | ||
1572 | bdrv_refresh_limits(bs, &local_err); | |
1573 | if (local_err) { | |
1574 | error_propagate(errp, local_err); | |
180ca19a | 1575 | return -EINVAL; |
01a56501 KW |
1576 | } |
1577 | ||
1578 | assert(bdrv_opt_mem_align(bs) != 0); | |
1579 | assert(bdrv_min_mem_align(bs) != 0); | |
1580 | assert(is_power_of_2(bs->bl.request_alignment)); | |
1581 | ||
0f12264e KW |
1582 | for (i = 0; i < bs->quiesce_counter; i++) { |
1583 | if (drv->bdrv_co_drain_begin) { | |
1584 | drv->bdrv_co_drain_begin(bs); | |
1585 | } | |
1586 | } | |
1587 | ||
01a56501 | 1588 | return 0; |
180ca19a MP |
1589 | open_failed: |
1590 | bs->drv = NULL; | |
1591 | if (bs->file != NULL) { | |
1592 | bdrv_unref_child(bs, bs->file); | |
1593 | bs->file = NULL; | |
1594 | } | |
01a56501 KW |
1595 | g_free(bs->opaque); |
1596 | bs->opaque = NULL; | |
01a56501 KW |
1597 | return ret; |
1598 | } | |
1599 | ||
680c7f96 KW |
1600 | BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, |
1601 | int flags, Error **errp) | |
1602 | { | |
1603 | BlockDriverState *bs; | |
1604 | int ret; | |
1605 | ||
1606 | bs = bdrv_new(); | |
1607 | bs->open_flags = flags; | |
1608 | bs->explicit_options = qdict_new(); | |
1609 | bs->options = qdict_new(); | |
1610 | bs->opaque = NULL; | |
1611 | ||
1612 | update_options_from_flags(bs->options, flags); | |
1613 | ||
1614 | ret = bdrv_open_driver(bs, drv, node_name, bs->options, flags, errp); | |
1615 | if (ret < 0) { | |
cb3e7f08 | 1616 | qobject_unref(bs->explicit_options); |
180ca19a | 1617 | bs->explicit_options = NULL; |
cb3e7f08 | 1618 | qobject_unref(bs->options); |
180ca19a | 1619 | bs->options = NULL; |
680c7f96 KW |
1620 | bdrv_unref(bs); |
1621 | return NULL; | |
1622 | } | |
1623 | ||
1624 | return bs; | |
1625 | } | |
1626 | ||
c5f3014b | 1627 | QemuOptsList bdrv_runtime_opts = { |
18edf289 KW |
1628 | .name = "bdrv_common", |
1629 | .head = QTAILQ_HEAD_INITIALIZER(bdrv_runtime_opts.head), | |
1630 | .desc = { | |
1631 | { | |
1632 | .name = "node-name", | |
1633 | .type = QEMU_OPT_STRING, | |
1634 | .help = "Node name of the block device node", | |
1635 | }, | |
62392ebb KW |
1636 | { |
1637 | .name = "driver", | |
1638 | .type = QEMU_OPT_STRING, | |
1639 | .help = "Block driver to use for the node", | |
1640 | }, | |
91a097e7 KW |
1641 | { |
1642 | .name = BDRV_OPT_CACHE_DIRECT, | |
1643 | .type = QEMU_OPT_BOOL, | |
1644 | .help = "Bypass software writeback cache on the host", | |
1645 | }, | |
1646 | { | |
1647 | .name = BDRV_OPT_CACHE_NO_FLUSH, | |
1648 | .type = QEMU_OPT_BOOL, | |
1649 | .help = "Ignore flush requests", | |
1650 | }, | |
f87a0e29 AG |
1651 | { |
1652 | .name = BDRV_OPT_READ_ONLY, | |
1653 | .type = QEMU_OPT_BOOL, | |
1654 | .help = "Node is opened in read-only mode", | |
1655 | }, | |
e35bdc12 KW |
1656 | { |
1657 | .name = BDRV_OPT_AUTO_READ_ONLY, | |
1658 | .type = QEMU_OPT_BOOL, | |
1659 | .help = "Node can become read-only if opening read-write fails", | |
1660 | }, | |
692e01a2 KW |
1661 | { |
1662 | .name = "detect-zeroes", | |
1663 | .type = QEMU_OPT_STRING, | |
1664 | .help = "try to optimize zero writes (off, on, unmap)", | |
1665 | }, | |
818584a4 | 1666 | { |
415bbca8 | 1667 | .name = BDRV_OPT_DISCARD, |
818584a4 KW |
1668 | .type = QEMU_OPT_STRING, |
1669 | .help = "discard operation (ignore/off, unmap/on)", | |
1670 | }, | |
5a9347c6 FZ |
1671 | { |
1672 | .name = BDRV_OPT_FORCE_SHARE, | |
1673 | .type = QEMU_OPT_BOOL, | |
1674 | .help = "always accept other writers (default: off)", | |
1675 | }, | |
18edf289 KW |
1676 | { /* end of list */ } |
1677 | }, | |
1678 | }; | |
1679 | ||
5a5e7f8c ML |
1680 | QemuOptsList bdrv_create_opts_simple = { |
1681 | .name = "simple-create-opts", | |
1682 | .head = QTAILQ_HEAD_INITIALIZER(bdrv_create_opts_simple.head), | |
fd17146c HR |
1683 | .desc = { |
1684 | { | |
1685 | .name = BLOCK_OPT_SIZE, | |
1686 | .type = QEMU_OPT_SIZE, | |
1687 | .help = "Virtual disk size" | |
1688 | }, | |
1689 | { | |
1690 | .name = BLOCK_OPT_PREALLOC, | |
1691 | .type = QEMU_OPT_STRING, | |
1692 | .help = "Preallocation mode (allowed values: off)" | |
1693 | }, | |
1694 | { /* end of list */ } | |
1695 | } | |
1696 | }; | |
1697 | ||
57915332 KW |
1698 | /* |
1699 | * Common part for opening disk images and files | |
b6ad491a KW |
1700 | * |
1701 | * Removes all processed options from *options. | |
57915332 | 1702 | */ |
5696c6e3 | 1703 | static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file, |
82dc8b41 | 1704 | QDict *options, Error **errp) |
57915332 KW |
1705 | { |
1706 | int ret, open_flags; | |
035fccdf | 1707 | const char *filename; |
62392ebb | 1708 | const char *driver_name = NULL; |
6913c0c2 | 1709 | const char *node_name = NULL; |
818584a4 | 1710 | const char *discard; |
18edf289 | 1711 | QemuOpts *opts; |
62392ebb | 1712 | BlockDriver *drv; |
34b5d2c6 | 1713 | Error *local_err = NULL; |
57915332 | 1714 | |
6405875c | 1715 | assert(bs->file == NULL); |
707ff828 | 1716 | assert(options != NULL && bs->options != options); |
57915332 | 1717 | |
62392ebb | 1718 | opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort); |
af175e85 | 1719 | if (!qemu_opts_absorb_qdict(opts, options, errp)) { |
62392ebb KW |
1720 | ret = -EINVAL; |
1721 | goto fail_opts; | |
1722 | } | |
1723 | ||
9b7e8691 AG |
1724 | update_flags_from_options(&bs->open_flags, opts); |
1725 | ||
62392ebb KW |
1726 | driver_name = qemu_opt_get(opts, "driver"); |
1727 | drv = bdrv_find_format(driver_name); | |
1728 | assert(drv != NULL); | |
1729 | ||
5a9347c6 FZ |
1730 | bs->force_share = qemu_opt_get_bool(opts, BDRV_OPT_FORCE_SHARE, false); |
1731 | ||
1732 | if (bs->force_share && (bs->open_flags & BDRV_O_RDWR)) { | |
1733 | error_setg(errp, | |
1734 | BDRV_OPT_FORCE_SHARE | |
1735 | "=on can only be used with read-only images"); | |
1736 | ret = -EINVAL; | |
1737 | goto fail_opts; | |
1738 | } | |
1739 | ||
45673671 | 1740 | if (file != NULL) { |
f30c66ba | 1741 | bdrv_refresh_filename(blk_bs(file)); |
5696c6e3 | 1742 | filename = blk_bs(file)->filename; |
45673671 | 1743 | } else { |
129c7d1c MA |
1744 | /* |
1745 | * Caution: while qdict_get_try_str() is fine, getting | |
1746 | * non-string types would require more care. When @options | |
1747 | * come from -blockdev or blockdev_add, its members are typed | |
1748 | * according to the QAPI schema, but when they come from | |
1749 | * -drive, they're all QString. | |
1750 | */ | |
45673671 KW |
1751 | filename = qdict_get_try_str(options, "filename"); |
1752 | } | |
1753 | ||
4a008240 | 1754 | if (drv->bdrv_needs_filename && (!filename || !filename[0])) { |
765003db KW |
1755 | error_setg(errp, "The '%s' block driver requires a file name", |
1756 | drv->format_name); | |
18edf289 KW |
1757 | ret = -EINVAL; |
1758 | goto fail_opts; | |
6913c0c2 | 1759 | } |
6913c0c2 | 1760 | |
82dc8b41 KW |
1761 | trace_bdrv_open_common(bs, filename ?: "", bs->open_flags, |
1762 | drv->format_name); | |
62392ebb | 1763 | |
82dc8b41 | 1764 | bs->read_only = !(bs->open_flags & BDRV_O_RDWR); |
b64ec4e4 FZ |
1765 | |
1766 | if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) { | |
8be25de6 KW |
1767 | if (!bs->read_only && bdrv_is_whitelisted(drv, true)) { |
1768 | ret = bdrv_apply_auto_read_only(bs, NULL, NULL); | |
1769 | } else { | |
1770 | ret = -ENOTSUP; | |
1771 | } | |
1772 | if (ret < 0) { | |
1773 | error_setg(errp, | |
1774 | !bs->read_only && bdrv_is_whitelisted(drv, true) | |
1775 | ? "Driver '%s' can only be used for read-only devices" | |
1776 | : "Driver '%s' is not whitelisted", | |
1777 | drv->format_name); | |
1778 | goto fail_opts; | |
1779 | } | |
b64ec4e4 | 1780 | } |
57915332 | 1781 | |
d3faa13e | 1782 | /* bdrv_new() and bdrv_close() make it so */ |
d73415a3 | 1783 | assert(qatomic_read(&bs->copy_on_read) == 0); |
d3faa13e | 1784 | |
82dc8b41 | 1785 | if (bs->open_flags & BDRV_O_COPY_ON_READ) { |
0ebd24e0 KW |
1786 | if (!bs->read_only) { |
1787 | bdrv_enable_copy_on_read(bs); | |
1788 | } else { | |
1789 | error_setg(errp, "Can't use copy-on-read on read-only device"); | |
18edf289 KW |
1790 | ret = -EINVAL; |
1791 | goto fail_opts; | |
0ebd24e0 | 1792 | } |
53fec9d3 SH |
1793 | } |
1794 | ||
415bbca8 | 1795 | discard = qemu_opt_get(opts, BDRV_OPT_DISCARD); |
818584a4 KW |
1796 | if (discard != NULL) { |
1797 | if (bdrv_parse_discard_flags(discard, &bs->open_flags) != 0) { | |
1798 | error_setg(errp, "Invalid discard option"); | |
1799 | ret = -EINVAL; | |
1800 | goto fail_opts; | |
1801 | } | |
1802 | } | |
1803 | ||
543770bd AG |
1804 | bs->detect_zeroes = |
1805 | bdrv_parse_detect_zeroes(opts, bs->open_flags, &local_err); | |
1806 | if (local_err) { | |
1807 | error_propagate(errp, local_err); | |
1808 | ret = -EINVAL; | |
1809 | goto fail_opts; | |
692e01a2 KW |
1810 | } |
1811 | ||
c2ad1b0c KW |
1812 | if (filename != NULL) { |
1813 | pstrcpy(bs->filename, sizeof(bs->filename), filename); | |
1814 | } else { | |
1815 | bs->filename[0] = '\0'; | |
1816 | } | |
91af7014 | 1817 | pstrcpy(bs->exact_filename, sizeof(bs->exact_filename), bs->filename); |
57915332 | 1818 | |
66f82cee | 1819 | /* Open the image, either directly or using a protocol */ |
82dc8b41 | 1820 | open_flags = bdrv_open_flags(bs, bs->open_flags); |
01a56501 | 1821 | node_name = qemu_opt_get(opts, "node-name"); |
57915332 | 1822 | |
01a56501 KW |
1823 | assert(!drv->bdrv_file_open || file == NULL); |
1824 | ret = bdrv_open_driver(bs, drv, node_name, options, open_flags, errp); | |
51762288 | 1825 | if (ret < 0) { |
01a56501 | 1826 | goto fail_opts; |
3baca891 KW |
1827 | } |
1828 | ||
18edf289 | 1829 | qemu_opts_del(opts); |
57915332 KW |
1830 | return 0; |
1831 | ||
18edf289 KW |
1832 | fail_opts: |
1833 | qemu_opts_del(opts); | |
57915332 KW |
1834 | return ret; |
1835 | } | |
1836 | ||
5e5c4f63 KW |
1837 | static QDict *parse_json_filename(const char *filename, Error **errp) |
1838 | { | |
1839 | QObject *options_obj; | |
1840 | QDict *options; | |
1841 | int ret; | |
1842 | ||
1843 | ret = strstart(filename, "json:", &filename); | |
1844 | assert(ret); | |
1845 | ||
5577fff7 | 1846 | options_obj = qobject_from_json(filename, errp); |
5e5c4f63 | 1847 | if (!options_obj) { |
5577fff7 | 1848 | error_prepend(errp, "Could not parse the JSON options: "); |
5e5c4f63 KW |
1849 | return NULL; |
1850 | } | |
1851 | ||
7dc847eb | 1852 | options = qobject_to(QDict, options_obj); |
ca6b6e1e | 1853 | if (!options) { |
cb3e7f08 | 1854 | qobject_unref(options_obj); |
5e5c4f63 KW |
1855 | error_setg(errp, "Invalid JSON object given"); |
1856 | return NULL; | |
1857 | } | |
1858 | ||
5e5c4f63 KW |
1859 | qdict_flatten(options); |
1860 | ||
1861 | return options; | |
1862 | } | |
1863 | ||
de3b53f0 KW |
1864 | static void parse_json_protocol(QDict *options, const char **pfilename, |
1865 | Error **errp) | |
1866 | { | |
1867 | QDict *json_options; | |
1868 | Error *local_err = NULL; | |
1869 | ||
1870 | /* Parse json: pseudo-protocol */ | |
1871 | if (!*pfilename || !g_str_has_prefix(*pfilename, "json:")) { | |
1872 | return; | |
1873 | } | |
1874 | ||
1875 | json_options = parse_json_filename(*pfilename, &local_err); | |
1876 | if (local_err) { | |
1877 | error_propagate(errp, local_err); | |
1878 | return; | |
1879 | } | |
1880 | ||
1881 | /* Options given in the filename have lower priority than options | |
1882 | * specified directly */ | |
1883 | qdict_join(options, json_options, false); | |
cb3e7f08 | 1884 | qobject_unref(json_options); |
de3b53f0 KW |
1885 | *pfilename = NULL; |
1886 | } | |
1887 | ||
b6ce07aa | 1888 | /* |
f54120ff KW |
1889 | * Fills in default options for opening images and converts the legacy |
1890 | * filename/flags pair to option QDict entries. | |
53a29513 HR |
1891 | * The BDRV_O_PROTOCOL flag in *flags will be set or cleared accordingly if a |
1892 | * block driver has been specified explicitly. | |
b6ce07aa | 1893 | */ |
de3b53f0 | 1894 | static int bdrv_fill_options(QDict **options, const char *filename, |
053e1578 | 1895 | int *flags, Error **errp) |
ea2384d3 | 1896 | { |
c2ad1b0c | 1897 | const char *drvname; |
53a29513 | 1898 | bool protocol = *flags & BDRV_O_PROTOCOL; |
e3fa4bfa | 1899 | bool parse_filename = false; |
053e1578 | 1900 | BlockDriver *drv = NULL; |
34b5d2c6 | 1901 | Error *local_err = NULL; |
83f64091 | 1902 | |
129c7d1c MA |
1903 | /* |
1904 | * Caution: while qdict_get_try_str() is fine, getting non-string | |
1905 | * types would require more care. When @options come from | |
1906 | * -blockdev or blockdev_add, its members are typed according to | |
1907 | * the QAPI schema, but when they come from -drive, they're all | |
1908 | * QString. | |
1909 | */ | |
53a29513 | 1910 | drvname = qdict_get_try_str(*options, "driver"); |
053e1578 HR |
1911 | if (drvname) { |
1912 | drv = bdrv_find_format(drvname); | |
1913 | if (!drv) { | |
1914 | error_setg(errp, "Unknown driver '%s'", drvname); | |
1915 | return -ENOENT; | |
1916 | } | |
1917 | /* If the user has explicitly specified the driver, this choice should | |
1918 | * override the BDRV_O_PROTOCOL flag */ | |
1919 | protocol = drv->bdrv_file_open; | |
53a29513 HR |
1920 | } |
1921 | ||
1922 | if (protocol) { | |
1923 | *flags |= BDRV_O_PROTOCOL; | |
1924 | } else { | |
1925 | *flags &= ~BDRV_O_PROTOCOL; | |
1926 | } | |
1927 | ||
91a097e7 KW |
1928 | /* Translate cache options from flags into options */ |
1929 | update_options_from_flags(*options, *flags); | |
1930 | ||
035fccdf | 1931 | /* Fetch the file name from the options QDict if necessary */ |
17b005f1 | 1932 | if (protocol && filename) { |
f54120ff | 1933 | if (!qdict_haskey(*options, "filename")) { |
46f5ac20 | 1934 | qdict_put_str(*options, "filename", filename); |
f54120ff KW |
1935 | parse_filename = true; |
1936 | } else { | |
1937 | error_setg(errp, "Can't specify 'file' and 'filename' options at " | |
1938 | "the same time"); | |
1939 | return -EINVAL; | |
1940 | } | |
035fccdf KW |
1941 | } |
1942 | ||
c2ad1b0c | 1943 | /* Find the right block driver */ |
129c7d1c | 1944 | /* See cautionary note on accessing @options above */ |
f54120ff | 1945 | filename = qdict_get_try_str(*options, "filename"); |
f54120ff | 1946 | |
053e1578 HR |
1947 | if (!drvname && protocol) { |
1948 | if (filename) { | |
1949 | drv = bdrv_find_protocol(filename, parse_filename, errp); | |
17b005f1 | 1950 | if (!drv) { |
053e1578 | 1951 | return -EINVAL; |
17b005f1 | 1952 | } |
053e1578 HR |
1953 | |
1954 | drvname = drv->format_name; | |
46f5ac20 | 1955 | qdict_put_str(*options, "driver", drvname); |
053e1578 HR |
1956 | } else { |
1957 | error_setg(errp, "Must specify either driver or file"); | |
1958 | return -EINVAL; | |
98289620 | 1959 | } |
c2ad1b0c KW |
1960 | } |
1961 | ||
17b005f1 | 1962 | assert(drv || !protocol); |
c2ad1b0c | 1963 | |
f54120ff | 1964 | /* Driver-specific filename parsing */ |
17b005f1 | 1965 | if (drv && drv->bdrv_parse_filename && parse_filename) { |
5acd9d81 | 1966 | drv->bdrv_parse_filename(filename, *options, &local_err); |
84d18f06 | 1967 | if (local_err) { |
34b5d2c6 | 1968 | error_propagate(errp, local_err); |
f54120ff | 1969 | return -EINVAL; |
6963a30d | 1970 | } |
cd5d031e HR |
1971 | |
1972 | if (!drv->bdrv_needs_filename) { | |
1973 | qdict_del(*options, "filename"); | |
cd5d031e | 1974 | } |
6963a30d KW |
1975 | } |
1976 | ||
f54120ff KW |
1977 | return 0; |
1978 | } | |
1979 | ||
3ef45e02 VSO |
1980 | static int bdrv_check_update_perm(BlockDriverState *bs, BlockReopenQueue *q, |
1981 | uint64_t new_used_perm, | |
1982 | uint64_t new_shared_perm, | |
1983 | GSList *ignore_children, | |
1984 | Error **errp); | |
c1cef672 | 1985 | |
148eb13c KW |
1986 | typedef struct BlockReopenQueueEntry { |
1987 | bool prepared; | |
69b736e7 | 1988 | bool perms_checked; |
148eb13c | 1989 | BDRVReopenState state; |
859443b0 | 1990 | QTAILQ_ENTRY(BlockReopenQueueEntry) entry; |
148eb13c KW |
1991 | } BlockReopenQueueEntry; |
1992 | ||
1993 | /* | |
1994 | * Return the flags that @bs will have after the reopens in @q have | |
1995 | * successfully completed. If @q is NULL (or @bs is not contained in @q), | |
1996 | * return the current flags. | |
1997 | */ | |
1998 | static int bdrv_reopen_get_flags(BlockReopenQueue *q, BlockDriverState *bs) | |
1999 | { | |
2000 | BlockReopenQueueEntry *entry; | |
2001 | ||
2002 | if (q != NULL) { | |
859443b0 | 2003 | QTAILQ_FOREACH(entry, q, entry) { |
148eb13c KW |
2004 | if (entry->state.bs == bs) { |
2005 | return entry->state.flags; | |
2006 | } | |
2007 | } | |
2008 | } | |
2009 | ||
2010 | return bs->open_flags; | |
2011 | } | |
2012 | ||
2013 | /* Returns whether the image file can be written to after the reopen queue @q | |
2014 | * has been successfully applied, or right now if @q is NULL. */ | |
cc022140 HR |
2015 | static bool bdrv_is_writable_after_reopen(BlockDriverState *bs, |
2016 | BlockReopenQueue *q) | |
148eb13c KW |
2017 | { |
2018 | int flags = bdrv_reopen_get_flags(q, bs); | |
2019 | ||
2020 | return (flags & (BDRV_O_RDWR | BDRV_O_INACTIVE)) == BDRV_O_RDWR; | |
2021 | } | |
2022 | ||
cc022140 HR |
2023 | /* |
2024 | * Return whether the BDS can be written to. This is not necessarily | |
2025 | * the same as !bdrv_is_read_only(bs), as inactivated images may not | |
2026 | * be written to but do not count as read-only images. | |
2027 | */ | |
2028 | bool bdrv_is_writable(BlockDriverState *bs) | |
2029 | { | |
2030 | return bdrv_is_writable_after_reopen(bs, NULL); | |
2031 | } | |
2032 | ||
3bf416ba VSO |
2033 | static char *bdrv_child_user_desc(BdrvChild *c) |
2034 | { | |
2035 | if (c->klass->get_parent_desc) { | |
2036 | return c->klass->get_parent_desc(c); | |
2037 | } | |
2038 | ||
2039 | return g_strdup("another user"); | |
2040 | } | |
2041 | ||
2042 | static bool bdrv_a_allow_b(BdrvChild *a, BdrvChild *b, Error **errp) | |
2043 | { | |
2044 | g_autofree char *user = NULL; | |
2045 | g_autofree char *perm_names = NULL; | |
2046 | ||
2047 | if ((b->perm & a->shared_perm) == b->perm) { | |
2048 | return true; | |
2049 | } | |
2050 | ||
2051 | perm_names = bdrv_perm_names(b->perm & ~a->shared_perm); | |
2052 | user = bdrv_child_user_desc(a); | |
2053 | error_setg(errp, "Conflicts with use by %s as '%s', which does not " | |
2054 | "allow '%s' on %s", | |
2055 | user, a->name, perm_names, bdrv_get_node_name(b->bs)); | |
2056 | ||
2057 | return false; | |
2058 | } | |
2059 | ||
bd57f8f7 VSO |
2060 | static bool bdrv_parent_perms_conflict(BlockDriverState *bs, |
2061 | GSList *ignore_children, | |
2062 | Error **errp) | |
3bf416ba VSO |
2063 | { |
2064 | BdrvChild *a, *b; | |
2065 | ||
2066 | /* | |
2067 | * During the loop we'll look at each pair twice. That's correct because | |
2068 | * bdrv_a_allow_b() is asymmetric and we should check each pair in both | |
2069 | * directions. | |
2070 | */ | |
2071 | QLIST_FOREACH(a, &bs->parents, next_parent) { | |
bd57f8f7 VSO |
2072 | if (g_slist_find(ignore_children, a)) { |
2073 | continue; | |
2074 | } | |
2075 | ||
3bf416ba | 2076 | QLIST_FOREACH(b, &bs->parents, next_parent) { |
bd57f8f7 | 2077 | if (a == b || g_slist_find(ignore_children, b)) { |
3bf416ba VSO |
2078 | continue; |
2079 | } | |
2080 | ||
2081 | if (!bdrv_a_allow_b(a, b, errp)) { | |
2082 | return true; | |
2083 | } | |
2084 | } | |
2085 | } | |
2086 | ||
2087 | return false; | |
2088 | } | |
2089 | ||
ffd1a5a2 | 2090 | static void bdrv_child_perm(BlockDriverState *bs, BlockDriverState *child_bs, |
e5d8a406 HR |
2091 | BdrvChild *c, BdrvChildRole role, |
2092 | BlockReopenQueue *reopen_queue, | |
ffd1a5a2 FZ |
2093 | uint64_t parent_perm, uint64_t parent_shared, |
2094 | uint64_t *nperm, uint64_t *nshared) | |
2095 | { | |
0b3ca76e | 2096 | assert(bs->drv && bs->drv->bdrv_child_perm); |
e5d8a406 | 2097 | bs->drv->bdrv_child_perm(bs, c, role, reopen_queue, |
0b3ca76e AG |
2098 | parent_perm, parent_shared, |
2099 | nperm, nshared); | |
e0995dc3 | 2100 | /* TODO Take force_share from reopen_queue */ |
ffd1a5a2 FZ |
2101 | if (child_bs && child_bs->force_share) { |
2102 | *nshared = BLK_PERM_ALL; | |
2103 | } | |
2104 | } | |
2105 | ||
bd57f8f7 VSO |
2106 | /* |
2107 | * Adds the whole subtree of @bs (including @bs itself) to the @list (except for | |
2108 | * nodes that are already in the @list, of course) so that final list is | |
2109 | * topologically sorted. Return the result (GSList @list object is updated, so | |
2110 | * don't use old reference after function call). | |
2111 | * | |
2112 | * On function start @list must be already topologically sorted and for any node | |
2113 | * in the @list the whole subtree of the node must be in the @list as well. The | |
2114 | * simplest way to satisfy this criteria: use only result of | |
2115 | * bdrv_topological_dfs() or NULL as @list parameter. | |
2116 | */ | |
2117 | static GSList *bdrv_topological_dfs(GSList *list, GHashTable *found, | |
2118 | BlockDriverState *bs) | |
2119 | { | |
2120 | BdrvChild *child; | |
2121 | g_autoptr(GHashTable) local_found = NULL; | |
2122 | ||
2123 | if (!found) { | |
2124 | assert(!list); | |
2125 | found = local_found = g_hash_table_new(NULL, NULL); | |
2126 | } | |
2127 | ||
2128 | if (g_hash_table_contains(found, bs)) { | |
2129 | return list; | |
2130 | } | |
2131 | g_hash_table_add(found, bs); | |
2132 | ||
2133 | QLIST_FOREACH(child, &bs->children, next) { | |
2134 | list = bdrv_topological_dfs(list, found, child->bs); | |
2135 | } | |
2136 | ||
2137 | return g_slist_prepend(list, bs); | |
2138 | } | |
2139 | ||
b0defa83 VSO |
2140 | static void bdrv_child_set_perm_commit(void *opaque) |
2141 | { | |
2142 | BdrvChild *c = opaque; | |
2143 | ||
2144 | c->has_backup_perm = false; | |
2145 | } | |
2146 | ||
2147 | static void bdrv_child_set_perm_abort(void *opaque) | |
2148 | { | |
2149 | BdrvChild *c = opaque; | |
2150 | /* | |
2151 | * We may have child->has_backup_perm unset at this point, as in case of | |
2152 | * _check_ stage of permission update failure we may _check_ not the whole | |
2153 | * subtree. Still, _abort_ is called on the whole subtree anyway. | |
2154 | */ | |
2155 | if (c->has_backup_perm) { | |
2156 | c->perm = c->backup_perm; | |
2157 | c->shared_perm = c->backup_shared_perm; | |
2158 | c->has_backup_perm = false; | |
2159 | } | |
2160 | } | |
2161 | ||
2162 | static TransactionActionDrv bdrv_child_set_pem_drv = { | |
2163 | .abort = bdrv_child_set_perm_abort, | |
2164 | .commit = bdrv_child_set_perm_commit, | |
2165 | }; | |
2166 | ||
2167 | /* | |
2168 | * With tran=NULL needs to be followed by direct call to either | |
2169 | * bdrv_child_set_perm_commit() or bdrv_child_set_perm_abort(). | |
2170 | * | |
2171 | * With non-NULL tran needs to be followed by tran_abort() or tran_commit() | |
2172 | * instead. | |
2173 | */ | |
2174 | static void bdrv_child_set_perm_safe(BdrvChild *c, uint64_t perm, | |
2175 | uint64_t shared, Transaction *tran) | |
2176 | { | |
2177 | if (!c->has_backup_perm) { | |
2178 | c->has_backup_perm = true; | |
2179 | c->backup_perm = c->perm; | |
2180 | c->backup_shared_perm = c->shared_perm; | |
2181 | } | |
2182 | /* | |
2183 | * Note: it's OK if c->has_backup_perm was already set, as we can find the | |
2184 | * same c twice during check_perm procedure | |
2185 | */ | |
2186 | ||
2187 | c->perm = perm; | |
2188 | c->shared_perm = shared; | |
2189 | ||
2190 | if (tran) { | |
2191 | tran_add(tran, &bdrv_child_set_pem_drv, c); | |
2192 | } | |
2193 | } | |
2194 | ||
2513ef59 VSO |
2195 | static void bdrv_drv_set_perm_commit(void *opaque) |
2196 | { | |
2197 | BlockDriverState *bs = opaque; | |
2198 | uint64_t cumulative_perms, cumulative_shared_perms; | |
2199 | ||
2200 | if (bs->drv->bdrv_set_perm) { | |
2201 | bdrv_get_cumulative_perm(bs, &cumulative_perms, | |
2202 | &cumulative_shared_perms); | |
2203 | bs->drv->bdrv_set_perm(bs, cumulative_perms, cumulative_shared_perms); | |
2204 | } | |
2205 | } | |
2206 | ||
2207 | static void bdrv_drv_set_perm_abort(void *opaque) | |
2208 | { | |
2209 | BlockDriverState *bs = opaque; | |
2210 | ||
2211 | if (bs->drv->bdrv_abort_perm_update) { | |
2212 | bs->drv->bdrv_abort_perm_update(bs); | |
2213 | } | |
2214 | } | |
2215 | ||
2216 | TransactionActionDrv bdrv_drv_set_perm_drv = { | |
2217 | .abort = bdrv_drv_set_perm_abort, | |
2218 | .commit = bdrv_drv_set_perm_commit, | |
2219 | }; | |
2220 | ||
2221 | static int bdrv_drv_set_perm(BlockDriverState *bs, uint64_t perm, | |
2222 | uint64_t shared_perm, Transaction *tran, | |
2223 | Error **errp) | |
2224 | { | |
2225 | if (!bs->drv) { | |
2226 | return 0; | |
2227 | } | |
2228 | ||
2229 | if (bs->drv->bdrv_check_perm) { | |
2230 | int ret = bs->drv->bdrv_check_perm(bs, perm, shared_perm, errp); | |
2231 | if (ret < 0) { | |
2232 | return ret; | |
2233 | } | |
2234 | } | |
2235 | ||
2236 | if (tran) { | |
2237 | tran_add(tran, &bdrv_drv_set_perm_drv, bs); | |
2238 | } | |
2239 | ||
2240 | return 0; | |
2241 | } | |
2242 | ||
0978623e VSO |
2243 | typedef struct BdrvReplaceChildState { |
2244 | BdrvChild *child; | |
2245 | BlockDriverState *old_bs; | |
2246 | } BdrvReplaceChildState; | |
2247 | ||
2248 | static void bdrv_replace_child_commit(void *opaque) | |
2249 | { | |
2250 | BdrvReplaceChildState *s = opaque; | |
2251 | ||
2252 | bdrv_unref(s->old_bs); | |
2253 | } | |
2254 | ||
2255 | static void bdrv_replace_child_abort(void *opaque) | |
2256 | { | |
2257 | BdrvReplaceChildState *s = opaque; | |
2258 | BlockDriverState *new_bs = s->child->bs; | |
2259 | ||
2260 | /* old_bs reference is transparently moved from @s to @s->child */ | |
2261 | bdrv_replace_child_noperm(s->child, s->old_bs); | |
2262 | bdrv_unref(new_bs); | |
2263 | } | |
2264 | ||
2265 | static TransactionActionDrv bdrv_replace_child_drv = { | |
2266 | .commit = bdrv_replace_child_commit, | |
2267 | .abort = bdrv_replace_child_abort, | |
2268 | .clean = g_free, | |
2269 | }; | |
2270 | ||
2271 | /* | |
2272 | * bdrv_replace_child_safe | |
2273 | * | |
2274 | * Note: real unref of old_bs is done only on commit. | |
2275 | */ | |
0978623e VSO |
2276 | static void bdrv_replace_child_safe(BdrvChild *child, BlockDriverState *new_bs, |
2277 | Transaction *tran) | |
2278 | { | |
2279 | BdrvReplaceChildState *s = g_new(BdrvReplaceChildState, 1); | |
2280 | *s = (BdrvReplaceChildState) { | |
2281 | .child = child, | |
2282 | .old_bs = child->bs, | |
2283 | }; | |
2284 | tran_add(tran, &bdrv_replace_child_drv, s); | |
2285 | ||
2286 | if (new_bs) { | |
2287 | bdrv_ref(new_bs); | |
2288 | } | |
2289 | bdrv_replace_child_noperm(child, new_bs); | |
2290 | /* old_bs reference is transparently moved from @child to @s */ | |
2291 | } | |
2292 | ||
33a610c3 KW |
2293 | /* |
2294 | * Check whether permissions on this node can be changed in a way that | |
2295 | * @cumulative_perms and @cumulative_shared_perms are the new cumulative | |
2296 | * permissions of all its parents. This involves checking whether all necessary | |
2297 | * permission changes to child nodes can be performed. | |
2298 | * | |
2299 | * A call to this function must always be followed by a call to bdrv_set_perm() | |
2300 | * or bdrv_abort_perm_update(). | |
2301 | */ | |
bd57f8f7 VSO |
2302 | static int bdrv_node_check_perm(BlockDriverState *bs, BlockReopenQueue *q, |
2303 | uint64_t cumulative_perms, | |
2304 | uint64_t cumulative_shared_perms, | |
b1d2bbeb VSO |
2305 | GSList *ignore_children, |
2306 | Transaction *tran, Error **errp) | |
33a610c3 KW |
2307 | { |
2308 | BlockDriver *drv = bs->drv; | |
2309 | BdrvChild *c; | |
2310 | int ret; | |
2311 | ||
2312 | /* Write permissions never work with read-only images */ | |
2313 | if ((cumulative_perms & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) && | |
cc022140 | 2314 | !bdrv_is_writable_after_reopen(bs, q)) |
33a610c3 | 2315 | { |
481e0eee HR |
2316 | if (!bdrv_is_writable_after_reopen(bs, NULL)) { |
2317 | error_setg(errp, "Block node is read-only"); | |
2318 | } else { | |
2319 | uint64_t current_perms, current_shared; | |
2320 | bdrv_get_cumulative_perm(bs, ¤t_perms, ¤t_shared); | |
2321 | if (current_perms & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) { | |
2322 | error_setg(errp, "Cannot make block node read-only, there is " | |
2323 | "a writer on it"); | |
2324 | } else { | |
2325 | error_setg(errp, "Cannot make block node read-only and create " | |
2326 | "a writer on it"); | |
2327 | } | |
2328 | } | |
2329 | ||
33a610c3 KW |
2330 | return -EPERM; |
2331 | } | |
2332 | ||
9c60a5d1 KW |
2333 | /* |
2334 | * Unaligned requests will automatically be aligned to bl.request_alignment | |
2335 | * and without RESIZE we can't extend requests to write to space beyond the | |
2336 | * end of the image, so it's required that the image size is aligned. | |
2337 | */ | |
2338 | if ((cumulative_perms & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)) && | |
2339 | !(cumulative_perms & BLK_PERM_RESIZE)) | |
2340 | { | |
2341 | if ((bs->total_sectors * BDRV_SECTOR_SIZE) % bs->bl.request_alignment) { | |
2342 | error_setg(errp, "Cannot get 'write' permission without 'resize': " | |
2343 | "Image size is not a multiple of request " | |
2344 | "alignment"); | |
2345 | return -EPERM; | |
2346 | } | |
2347 | } | |
2348 | ||
33a610c3 KW |
2349 | /* Check this node */ |
2350 | if (!drv) { | |
2351 | return 0; | |
2352 | } | |
2353 | ||
b1d2bbeb | 2354 | ret = bdrv_drv_set_perm(bs, cumulative_perms, cumulative_shared_perms, tran, |
2513ef59 VSO |
2355 | errp); |
2356 | if (ret < 0) { | |
2357 | return ret; | |
33a610c3 KW |
2358 | } |
2359 | ||
78e421c9 | 2360 | /* Drivers that never have children can omit .bdrv_child_perm() */ |
33a610c3 | 2361 | if (!drv->bdrv_child_perm) { |
78e421c9 | 2362 | assert(QLIST_EMPTY(&bs->children)); |
33a610c3 KW |
2363 | return 0; |
2364 | } | |
2365 | ||
2366 | /* Check all children */ | |
2367 | QLIST_FOREACH(c, &bs->children, next) { | |
2368 | uint64_t cur_perm, cur_shared; | |
9eab1544 | 2369 | |
e5d8a406 | 2370 | bdrv_child_perm(bs, c->bs, c, c->role, q, |
ffd1a5a2 FZ |
2371 | cumulative_perms, cumulative_shared_perms, |
2372 | &cur_perm, &cur_shared); | |
b1d2bbeb | 2373 | bdrv_child_set_perm_safe(c, cur_perm, cur_shared, tran); |
bd57f8f7 VSO |
2374 | } |
2375 | ||
2376 | return 0; | |
2377 | } | |
3ef45e02 | 2378 | |
b1d2bbeb VSO |
2379 | /* |
2380 | * If use_cumulative_perms is true, use cumulative_perms and | |
2381 | * cumulative_shared_perms for first element of the list. Otherwise just refresh | |
2382 | * all permissions. | |
2383 | */ | |
2384 | static int bdrv_check_perm_common(GSList *list, BlockReopenQueue *q, | |
2385 | bool use_cumulative_perms, | |
2386 | uint64_t cumulative_perms, | |
2387 | uint64_t cumulative_shared_perms, | |
2388 | GSList *ignore_children, | |
2389 | Transaction *tran, Error **errp) | |
bd57f8f7 VSO |
2390 | { |
2391 | int ret; | |
b1d2bbeb | 2392 | BlockDriverState *bs; |
bd57f8f7 | 2393 | |
b1d2bbeb | 2394 | if (use_cumulative_perms) { |
bd57f8f7 VSO |
2395 | bs = list->data; |
2396 | ||
b1d2bbeb VSO |
2397 | ret = bdrv_node_check_perm(bs, q, cumulative_perms, |
2398 | cumulative_shared_perms, | |
2399 | ignore_children, tran, errp); | |
2400 | if (ret < 0) { | |
2401 | return ret; | |
2402 | } | |
bd57f8f7 | 2403 | |
b1d2bbeb VSO |
2404 | list = list->next; |
2405 | } | |
2406 | ||
2407 | for ( ; list; list = list->next) { | |
2408 | bs = list->data; | |
2409 | ||
2410 | if (bdrv_parent_perms_conflict(bs, ignore_children, errp)) { | |
2411 | return -EINVAL; | |
bd57f8f7 VSO |
2412 | } |
2413 | ||
b1d2bbeb VSO |
2414 | bdrv_get_cumulative_perm(bs, &cumulative_perms, |
2415 | &cumulative_shared_perms); | |
2416 | ||
bd57f8f7 VSO |
2417 | ret = bdrv_node_check_perm(bs, q, cumulative_perms, |
2418 | cumulative_shared_perms, | |
b1d2bbeb | 2419 | ignore_children, tran, errp); |
33a610c3 KW |
2420 | if (ret < 0) { |
2421 | return ret; | |
2422 | } | |
2423 | } | |
2424 | ||
2425 | return 0; | |
2426 | } | |
2427 | ||
b1d2bbeb VSO |
2428 | static int bdrv_check_perm(BlockDriverState *bs, BlockReopenQueue *q, |
2429 | uint64_t cumulative_perms, | |
2430 | uint64_t cumulative_shared_perms, | |
2431 | GSList *ignore_children, Error **errp) | |
2432 | { | |
2433 | g_autoptr(GSList) list = bdrv_topological_dfs(NULL, NULL, bs); | |
2434 | return bdrv_check_perm_common(list, q, true, cumulative_perms, | |
2435 | cumulative_shared_perms, ignore_children, | |
2436 | NULL, errp); | |
2437 | } | |
2438 | ||
2439 | static int bdrv_list_refresh_perms(GSList *list, BlockReopenQueue *q, | |
2440 | Transaction *tran, Error **errp) | |
2441 | { | |
2442 | return bdrv_check_perm_common(list, q, false, 0, 0, NULL, tran, errp); | |
2443 | } | |
2444 | ||
33a610c3 KW |
2445 | /* |
2446 | * Notifies drivers that after a previous bdrv_check_perm() call, the | |
2447 | * permission update is not performed and any preparations made for it (e.g. | |
2448 | * taken file locks) need to be undone. | |
33a610c3 | 2449 | */ |
bd57f8f7 | 2450 | static void bdrv_node_abort_perm_update(BlockDriverState *bs) |
33a610c3 KW |
2451 | { |
2452 | BlockDriver *drv = bs->drv; | |
2453 | BdrvChild *c; | |
2454 | ||
2455 | if (!drv) { | |
2456 | return; | |
2457 | } | |
2458 | ||
2513ef59 | 2459 | bdrv_drv_set_perm_abort(bs); |
33a610c3 KW |
2460 | |
2461 | QLIST_FOREACH(c, &bs->children, next) { | |
3ef45e02 | 2462 | bdrv_child_set_perm_abort(c); |
33a610c3 KW |
2463 | } |
2464 | } | |
2465 | ||
b1d2bbeb | 2466 | static void bdrv_list_abort_perm_update(GSList *list) |
bd57f8f7 | 2467 | { |
bd57f8f7 VSO |
2468 | for ( ; list; list = list->next) { |
2469 | bdrv_node_abort_perm_update((BlockDriverState *)list->data); | |
2470 | } | |
2471 | } | |
2472 | ||
b1d2bbeb VSO |
2473 | static void bdrv_abort_perm_update(BlockDriverState *bs) |
2474 | { | |
2475 | g_autoptr(GSList) list = bdrv_topological_dfs(NULL, NULL, bs); | |
2476 | return bdrv_list_abort_perm_update(list); | |
2477 | } | |
2478 | ||
bd57f8f7 | 2479 | static void bdrv_node_set_perm(BlockDriverState *bs) |
33a610c3 KW |
2480 | { |
2481 | BlockDriver *drv = bs->drv; | |
2482 | BdrvChild *c; | |
2483 | ||
2484 | if (!drv) { | |
2485 | return; | |
2486 | } | |
2487 | ||
2513ef59 | 2488 | bdrv_drv_set_perm_commit(bs); |
33a610c3 | 2489 | |
78e421c9 | 2490 | /* Drivers that never have children can omit .bdrv_child_perm() */ |
33a610c3 | 2491 | if (!drv->bdrv_child_perm) { |
78e421c9 | 2492 | assert(QLIST_EMPTY(&bs->children)); |
33a610c3 KW |
2493 | return; |
2494 | } | |
2495 | ||
2496 | /* Update all children */ | |
2497 | QLIST_FOREACH(c, &bs->children, next) { | |
3ef45e02 | 2498 | bdrv_child_set_perm_commit(c); |
bd57f8f7 VSO |
2499 | } |
2500 | } | |
2501 | ||
b1d2bbeb | 2502 | static void bdrv_list_set_perm(GSList *list) |
bd57f8f7 | 2503 | { |
bd57f8f7 VSO |
2504 | for ( ; list; list = list->next) { |
2505 | bdrv_node_set_perm((BlockDriverState *)list->data); | |
33a610c3 KW |
2506 | } |
2507 | } | |
2508 | ||
b1d2bbeb VSO |
2509 | static void bdrv_set_perm(BlockDriverState *bs) |
2510 | { | |
2511 | g_autoptr(GSList) list = bdrv_topological_dfs(NULL, NULL, bs); | |
2512 | return bdrv_list_set_perm(list); | |
2513 | } | |
2514 | ||
c7a0f2be KW |
2515 | void bdrv_get_cumulative_perm(BlockDriverState *bs, uint64_t *perm, |
2516 | uint64_t *shared_perm) | |
33a610c3 KW |
2517 | { |
2518 | BdrvChild *c; | |
2519 | uint64_t cumulative_perms = 0; | |
2520 | uint64_t cumulative_shared_perms = BLK_PERM_ALL; | |
2521 | ||
2522 | QLIST_FOREACH(c, &bs->parents, next_parent) { | |
2523 | cumulative_perms |= c->perm; | |
2524 | cumulative_shared_perms &= c->shared_perm; | |
2525 | } | |
2526 | ||
2527 | *perm = cumulative_perms; | |
2528 | *shared_perm = cumulative_shared_perms; | |
2529 | } | |
2530 | ||
5176196c | 2531 | char *bdrv_perm_names(uint64_t perm) |
d083319f KW |
2532 | { |
2533 | struct perm_name { | |
2534 | uint64_t perm; | |
2535 | const char *name; | |
2536 | } permissions[] = { | |
2537 | { BLK_PERM_CONSISTENT_READ, "consistent read" }, | |
2538 | { BLK_PERM_WRITE, "write" }, | |
2539 | { BLK_PERM_WRITE_UNCHANGED, "write unchanged" }, | |
2540 | { BLK_PERM_RESIZE, "resize" }, | |
2541 | { BLK_PERM_GRAPH_MOD, "change children" }, | |
2542 | { 0, NULL } | |
2543 | }; | |
2544 | ||
e2a7423a | 2545 | GString *result = g_string_sized_new(30); |
d083319f KW |
2546 | struct perm_name *p; |
2547 | ||
2548 | for (p = permissions; p->name; p++) { | |
2549 | if (perm & p->perm) { | |
e2a7423a AG |
2550 | if (result->len > 0) { |
2551 | g_string_append(result, ", "); | |
2552 | } | |
2553 | g_string_append(result, p->name); | |
d083319f KW |
2554 | } |
2555 | } | |
2556 | ||
e2a7423a | 2557 | return g_string_free(result, FALSE); |
d083319f KW |
2558 | } |
2559 | ||
33a610c3 KW |
2560 | /* |
2561 | * Checks whether a new reference to @bs can be added if the new user requires | |
46181129 KW |
2562 | * @new_used_perm/@new_shared_perm as its permissions. If @ignore_children is |
2563 | * set, the BdrvChild objects in this list are ignored in the calculations; | |
2564 | * this allows checking permission updates for an existing reference. | |
33a610c3 KW |
2565 | * |
2566 | * Needs to be followed by a call to either bdrv_set_perm() or | |
2567 | * bdrv_abort_perm_update(). */ | |
3121fb45 KW |
2568 | static int bdrv_check_update_perm(BlockDriverState *bs, BlockReopenQueue *q, |
2569 | uint64_t new_used_perm, | |
d5e6f437 | 2570 | uint64_t new_shared_perm, |
9eab1544 | 2571 | GSList *ignore_children, |
9eab1544 | 2572 | Error **errp) |
d5e6f437 KW |
2573 | { |
2574 | BdrvChild *c; | |
33a610c3 KW |
2575 | uint64_t cumulative_perms = new_used_perm; |
2576 | uint64_t cumulative_shared_perms = new_shared_perm; | |
d5e6f437 | 2577 | |
9eab1544 | 2578 | |
d5e6f437 KW |
2579 | /* There is no reason why anyone couldn't tolerate write_unchanged */ |
2580 | assert(new_shared_perm & BLK_PERM_WRITE_UNCHANGED); | |
2581 | ||
2582 | QLIST_FOREACH(c, &bs->parents, next_parent) { | |
46181129 | 2583 | if (g_slist_find(ignore_children, c)) { |
d5e6f437 KW |
2584 | continue; |
2585 | } | |
2586 | ||
d083319f KW |
2587 | if ((new_used_perm & c->shared_perm) != new_used_perm) { |
2588 | char *user = bdrv_child_user_desc(c); | |
2589 | char *perm_names = bdrv_perm_names(new_used_perm & ~c->shared_perm); | |
9eab1544 | 2590 | |
d083319f KW |
2591 | error_setg(errp, "Conflicts with use by %s as '%s', which does not " |
2592 | "allow '%s' on %s", | |
2593 | user, c->name, perm_names, bdrv_get_node_name(c->bs)); | |
2594 | g_free(user); | |
2595 | g_free(perm_names); | |
2596 | return -EPERM; | |
2597 | } | |
2598 | ||
2599 | if ((c->perm & new_shared_perm) != c->perm) { | |
2600 | char *user = bdrv_child_user_desc(c); | |
2601 | char *perm_names = bdrv_perm_names(c->perm & ~new_shared_perm); | |
9eab1544 | 2602 | |
d083319f KW |
2603 | error_setg(errp, "Conflicts with use by %s as '%s', which uses " |
2604 | "'%s' on %s", | |
2605 | user, c->name, perm_names, bdrv_get_node_name(c->bs)); | |
2606 | g_free(user); | |
2607 | g_free(perm_names); | |
d5e6f437 KW |
2608 | return -EPERM; |
2609 | } | |
33a610c3 KW |
2610 | |
2611 | cumulative_perms |= c->perm; | |
2612 | cumulative_shared_perms &= c->shared_perm; | |
d5e6f437 KW |
2613 | } |
2614 | ||
3121fb45 | 2615 | return bdrv_check_perm(bs, q, cumulative_perms, cumulative_shared_perms, |
071b474f | 2616 | ignore_children, errp); |
33a610c3 KW |
2617 | } |
2618 | ||
071b474f | 2619 | static int bdrv_refresh_perms(BlockDriverState *bs, Error **errp) |
bb87e4d1 VSO |
2620 | { |
2621 | int ret; | |
b1d2bbeb VSO |
2622 | Transaction *tran = tran_new(); |
2623 | g_autoptr(GSList) list = bdrv_topological_dfs(NULL, NULL, bs); | |
bb87e4d1 | 2624 | |
b1d2bbeb VSO |
2625 | ret = bdrv_list_refresh_perms(list, NULL, tran, errp); |
2626 | tran_finalize(tran, ret); | |
bb87e4d1 | 2627 | |
b1d2bbeb | 2628 | return ret; |
bb87e4d1 VSO |
2629 | } |
2630 | ||
33a610c3 KW |
2631 | int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, |
2632 | Error **errp) | |
2633 | { | |
1046779e | 2634 | Error *local_err = NULL; |
83928dc4 | 2635 | Transaction *tran = tran_new(); |
33a610c3 KW |
2636 | int ret; |
2637 | ||
83928dc4 VSO |
2638 | bdrv_child_set_perm_safe(c, perm, shared, tran); |
2639 | ||
2640 | ret = bdrv_refresh_perms(c->bs, &local_err); | |
2641 | ||
2642 | tran_finalize(tran, ret); | |
2643 | ||
33a610c3 | 2644 | if (ret < 0) { |
071b474f VSO |
2645 | if ((perm & ~c->perm) || (c->shared_perm & ~shared)) { |
2646 | /* tighten permissions */ | |
1046779e HR |
2647 | error_propagate(errp, local_err); |
2648 | } else { | |
2649 | /* | |
2650 | * Our caller may intend to only loosen restrictions and | |
2651 | * does not expect this function to fail. Errors are not | |
2652 | * fatal in such a case, so we can just hide them from our | |
2653 | * caller. | |
2654 | */ | |
2655 | error_free(local_err); | |
2656 | ret = 0; | |
2657 | } | |
33a610c3 KW |
2658 | } |
2659 | ||
83928dc4 | 2660 | return ret; |
d5e6f437 KW |
2661 | } |
2662 | ||
c1087f12 HR |
2663 | int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp) |
2664 | { | |
2665 | uint64_t parent_perms, parent_shared; | |
2666 | uint64_t perms, shared; | |
2667 | ||
2668 | bdrv_get_cumulative_perm(bs, &parent_perms, &parent_shared); | |
e5d8a406 | 2669 | bdrv_child_perm(bs, c->bs, c, c->role, NULL, |
bf8e925e | 2670 | parent_perms, parent_shared, &perms, &shared); |
c1087f12 HR |
2671 | |
2672 | return bdrv_child_try_set_perm(c, perms, shared, errp); | |
2673 | } | |
2674 | ||
87278af1 HR |
2675 | /* |
2676 | * Default implementation for .bdrv_child_perm() for block filters: | |
2677 | * Forward CONSISTENT_READ, WRITE, WRITE_UNCHANGED, and RESIZE to the | |
2678 | * filtered child. | |
2679 | */ | |
2680 | static void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, | |
87278af1 HR |
2681 | BdrvChildRole role, |
2682 | BlockReopenQueue *reopen_queue, | |
2683 | uint64_t perm, uint64_t shared, | |
2684 | uint64_t *nperm, uint64_t *nshared) | |
6a1b9ee1 | 2685 | { |
e444fa83 KW |
2686 | *nperm = perm & DEFAULT_PERM_PASSTHROUGH; |
2687 | *nshared = (shared & DEFAULT_PERM_PASSTHROUGH) | DEFAULT_PERM_UNCHANGED; | |
6a1b9ee1 KW |
2688 | } |
2689 | ||
70082db4 | 2690 | static void bdrv_default_perms_for_cow(BlockDriverState *bs, BdrvChild *c, |
70082db4 HR |
2691 | BdrvChildRole role, |
2692 | BlockReopenQueue *reopen_queue, | |
2693 | uint64_t perm, uint64_t shared, | |
2694 | uint64_t *nperm, uint64_t *nshared) | |
2695 | { | |
e5d8a406 | 2696 | assert(role & BDRV_CHILD_COW); |
70082db4 HR |
2697 | |
2698 | /* | |
2699 | * We want consistent read from backing files if the parent needs it. | |
2700 | * No other operations are performed on backing files. | |
2701 | */ | |
2702 | perm &= BLK_PERM_CONSISTENT_READ; | |
2703 | ||
2704 | /* | |
2705 | * If the parent can deal with changing data, we're okay with a | |
2706 | * writable and resizable backing file. | |
2707 | * TODO Require !(perm & BLK_PERM_CONSISTENT_READ), too? | |
2708 | */ | |
2709 | if (shared & BLK_PERM_WRITE) { | |
2710 | shared = BLK_PERM_WRITE | BLK_PERM_RESIZE; | |
2711 | } else { | |
2712 | shared = 0; | |
2713 | } | |
2714 | ||
2715 | shared |= BLK_PERM_CONSISTENT_READ | BLK_PERM_GRAPH_MOD | | |
2716 | BLK_PERM_WRITE_UNCHANGED; | |
2717 | ||
2718 | if (bs->open_flags & BDRV_O_INACTIVE) { | |
2719 | shared |= BLK_PERM_WRITE | BLK_PERM_RESIZE; | |
2720 | } | |
2721 | ||
2722 | *nperm = perm; | |
2723 | *nshared = shared; | |
2724 | } | |
2725 | ||
6f838a4b | 2726 | static void bdrv_default_perms_for_storage(BlockDriverState *bs, BdrvChild *c, |
6f838a4b HR |
2727 | BdrvChildRole role, |
2728 | BlockReopenQueue *reopen_queue, | |
2729 | uint64_t perm, uint64_t shared, | |
2730 | uint64_t *nperm, uint64_t *nshared) | |
2731 | { | |
2732 | int flags; | |
2733 | ||
e5d8a406 | 2734 | assert(role & (BDRV_CHILD_METADATA | BDRV_CHILD_DATA)); |
6f838a4b HR |
2735 | |
2736 | flags = bdrv_reopen_get_flags(reopen_queue, bs); | |
2737 | ||
2738 | /* | |
2739 | * Apart from the modifications below, the same permissions are | |
2740 | * forwarded and left alone as for filters | |
2741 | */ | |
e5d8a406 | 2742 | bdrv_filter_default_perms(bs, c, role, reopen_queue, |
6f838a4b HR |
2743 | perm, shared, &perm, &shared); |
2744 | ||
f889054f HR |
2745 | if (role & BDRV_CHILD_METADATA) { |
2746 | /* Format drivers may touch metadata even if the guest doesn't write */ | |
2747 | if (bdrv_is_writable_after_reopen(bs, reopen_queue)) { | |
2748 | perm |= BLK_PERM_WRITE | BLK_PERM_RESIZE; | |
2749 | } | |
2750 | ||
2751 | /* | |
2752 | * bs->file always needs to be consistent because of the | |
2753 | * metadata. We can never allow other users to resize or write | |
2754 | * to it. | |
2755 | */ | |
2756 | if (!(flags & BDRV_O_NO_IO)) { | |
2757 | perm |= BLK_PERM_CONSISTENT_READ; | |
2758 | } | |
2759 | shared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE); | |
6f838a4b HR |
2760 | } |
2761 | ||
f889054f HR |
2762 | if (role & BDRV_CHILD_DATA) { |
2763 | /* | |
2764 | * Technically, everything in this block is a subset of the | |
2765 | * BDRV_CHILD_METADATA path taken above, and so this could | |
2766 | * be an "else if" branch. However, that is not obvious, and | |
2767 | * this function is not performance critical, therefore we let | |
2768 | * this be an independent "if". | |
2769 | */ | |
2770 | ||
2771 | /* | |
2772 | * We cannot allow other users to resize the file because the | |
2773 | * format driver might have some assumptions about the size | |
2774 | * (e.g. because it is stored in metadata, or because the file | |
2775 | * is split into fixed-size data files). | |
2776 | */ | |
2777 | shared &= ~BLK_PERM_RESIZE; | |
2778 | ||
2779 | /* | |
2780 | * WRITE_UNCHANGED often cannot be performed as such on the | |
2781 | * data file. For example, the qcow2 driver may still need to | |
2782 | * write copied clusters on copy-on-read. | |
2783 | */ | |
2784 | if (perm & BLK_PERM_WRITE_UNCHANGED) { | |
2785 | perm |= BLK_PERM_WRITE; | |
2786 | } | |
2787 | ||
2788 | /* | |
2789 | * If the data file is written to, the format driver may | |
2790 | * expect to be able to resize it by writing beyond the EOF. | |
2791 | */ | |
2792 | if (perm & BLK_PERM_WRITE) { | |
2793 | perm |= BLK_PERM_RESIZE; | |
2794 | } | |
6f838a4b | 2795 | } |
6f838a4b HR |
2796 | |
2797 | if (bs->open_flags & BDRV_O_INACTIVE) { | |
2798 | shared |= BLK_PERM_WRITE | BLK_PERM_RESIZE; | |
2799 | } | |
2800 | ||
2801 | *nperm = perm; | |
2802 | *nshared = shared; | |
2803 | } | |
2804 | ||
2519f549 | 2805 | void bdrv_default_perms(BlockDriverState *bs, BdrvChild *c, |
e5d8a406 | 2806 | BdrvChildRole role, BlockReopenQueue *reopen_queue, |
2519f549 HR |
2807 | uint64_t perm, uint64_t shared, |
2808 | uint64_t *nperm, uint64_t *nshared) | |
2809 | { | |
2519f549 HR |
2810 | if (role & BDRV_CHILD_FILTERED) { |
2811 | assert(!(role & (BDRV_CHILD_DATA | BDRV_CHILD_METADATA | | |
2812 | BDRV_CHILD_COW))); | |
e5d8a406 | 2813 | bdrv_filter_default_perms(bs, c, role, reopen_queue, |
2519f549 HR |
2814 | perm, shared, nperm, nshared); |
2815 | } else if (role & BDRV_CHILD_COW) { | |
2816 | assert(!(role & (BDRV_CHILD_DATA | BDRV_CHILD_METADATA))); | |
e5d8a406 | 2817 | bdrv_default_perms_for_cow(bs, c, role, reopen_queue, |
2519f549 HR |
2818 | perm, shared, nperm, nshared); |
2819 | } else if (role & (BDRV_CHILD_METADATA | BDRV_CHILD_DATA)) { | |
e5d8a406 | 2820 | bdrv_default_perms_for_storage(bs, c, role, reopen_queue, |
2519f549 HR |
2821 | perm, shared, nperm, nshared); |
2822 | } else { | |
2823 | g_assert_not_reached(); | |
2824 | } | |
2825 | } | |
2826 | ||
7b1d9c4d HR |
2827 | uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm) |
2828 | { | |
2829 | static const uint64_t permissions[] = { | |
2830 | [BLOCK_PERMISSION_CONSISTENT_READ] = BLK_PERM_CONSISTENT_READ, | |
2831 | [BLOCK_PERMISSION_WRITE] = BLK_PERM_WRITE, | |
2832 | [BLOCK_PERMISSION_WRITE_UNCHANGED] = BLK_PERM_WRITE_UNCHANGED, | |
2833 | [BLOCK_PERMISSION_RESIZE] = BLK_PERM_RESIZE, | |
2834 | [BLOCK_PERMISSION_GRAPH_MOD] = BLK_PERM_GRAPH_MOD, | |
2835 | }; | |
2836 | ||
2837 | QEMU_BUILD_BUG_ON(ARRAY_SIZE(permissions) != BLOCK_PERMISSION__MAX); | |
2838 | QEMU_BUILD_BUG_ON(1UL << ARRAY_SIZE(permissions) != BLK_PERM_ALL + 1); | |
2839 | ||
2840 | assert(qapi_perm < BLOCK_PERMISSION__MAX); | |
2841 | ||
2842 | return permissions[qapi_perm]; | |
2843 | } | |
2844 | ||
8ee03995 KW |
2845 | static void bdrv_replace_child_noperm(BdrvChild *child, |
2846 | BlockDriverState *new_bs) | |
e9740bc6 KW |
2847 | { |
2848 | BlockDriverState *old_bs = child->bs; | |
debc2927 HR |
2849 | int new_bs_quiesce_counter; |
2850 | int drain_saldo; | |
e9740bc6 | 2851 | |
2cad1ebe AG |
2852 | assert(!child->frozen); |
2853 | ||
bb2614e9 FZ |
2854 | if (old_bs && new_bs) { |
2855 | assert(bdrv_get_aio_context(old_bs) == bdrv_get_aio_context(new_bs)); | |
2856 | } | |
debc2927 HR |
2857 | |
2858 | new_bs_quiesce_counter = (new_bs ? new_bs->quiesce_counter : 0); | |
2859 | drain_saldo = new_bs_quiesce_counter - child->parent_quiesce_counter; | |
2860 | ||
2861 | /* | |
2862 | * If the new child node is drained but the old one was not, flush | |
2863 | * all outstanding requests to the old child node. | |
2864 | */ | |
bd86fb99 | 2865 | while (drain_saldo > 0 && child->klass->drained_begin) { |
debc2927 HR |
2866 | bdrv_parent_drained_begin_single(child, true); |
2867 | drain_saldo--; | |
2868 | } | |
2869 | ||
e9740bc6 | 2870 | if (old_bs) { |
d736f119 KW |
2871 | /* Detach first so that the recursive drain sections coming from @child |
2872 | * are already gone and we only end the drain sections that came from | |
2873 | * elsewhere. */ | |
bd86fb99 HR |
2874 | if (child->klass->detach) { |
2875 | child->klass->detach(child); | |
d736f119 | 2876 | } |
e9740bc6 KW |
2877 | QLIST_REMOVE(child, next_parent); |
2878 | } | |
36fe1331 KW |
2879 | |
2880 | child->bs = new_bs; | |
2881 | ||
e9740bc6 KW |
2882 | if (new_bs) { |
2883 | QLIST_INSERT_HEAD(&new_bs->parents, child, next_parent); | |
debc2927 HR |
2884 | |
2885 | /* | |
2886 | * Detaching the old node may have led to the new node's | |
2887 | * quiesce_counter having been decreased. Not a problem, we | |
2888 | * just need to recognize this here and then invoke | |
2889 | * drained_end appropriately more often. | |
2890 | */ | |
2891 | assert(new_bs->quiesce_counter <= new_bs_quiesce_counter); | |
2892 | drain_saldo += new_bs->quiesce_counter - new_bs_quiesce_counter; | |
33a610c3 | 2893 | |
d736f119 KW |
2894 | /* Attach only after starting new drained sections, so that recursive |
2895 | * drain sections coming from @child don't get an extra .drained_begin | |
2896 | * callback. */ | |
bd86fb99 HR |
2897 | if (child->klass->attach) { |
2898 | child->klass->attach(child); | |
8ee03995 KW |
2899 | } |
2900 | } | |
debc2927 HR |
2901 | |
2902 | /* | |
2903 | * If the old child node was drained but the new one is not, allow | |
2904 | * requests to come in only after the new node has been attached. | |
2905 | */ | |
bd86fb99 | 2906 | while (drain_saldo < 0 && child->klass->drained_end) { |
debc2927 HR |
2907 | bdrv_parent_drained_end_single(child); |
2908 | drain_saldo++; | |
2909 | } | |
8ee03995 | 2910 | } |
33a610c3 | 2911 | |
466787fb KW |
2912 | /* |
2913 | * Updates @child to change its reference to point to @new_bs, including | |
e3a6e0da | 2914 | * checking and applying the necessary permission updates both to the old node |
466787fb KW |
2915 | * and to @new_bs. |
2916 | * | |
2917 | * NULL is passed as @new_bs for removing the reference before freeing @child. | |
2918 | * | |
2919 | * If @new_bs is not NULL, bdrv_check_perm() must be called beforehand, as this | |
2920 | * function uses bdrv_set_perm() to update the permissions according to the new | |
2921 | * reference that @new_bs gets. | |
7b99a266 HR |
2922 | * |
2923 | * Callers must ensure that child->frozen is false. | |
466787fb KW |
2924 | */ |
2925 | static void bdrv_replace_child(BdrvChild *child, BlockDriverState *new_bs) | |
8ee03995 KW |
2926 | { |
2927 | BlockDriverState *old_bs = child->bs; | |
8ee03995 | 2928 | |
7b99a266 | 2929 | /* Asserts that child->frozen == false */ |
8aecf1d1 KW |
2930 | bdrv_replace_child_noperm(child, new_bs); |
2931 | ||
87ace5f8 HR |
2932 | /* |
2933 | * Start with the new node's permissions. If @new_bs is a (direct | |
2934 | * or indirect) child of @old_bs, we must complete the permission | |
2935 | * update on @new_bs before we loosen the restrictions on @old_bs. | |
2936 | * Otherwise, bdrv_check_perm() on @old_bs would re-initiate | |
2937 | * updating the permissions of @new_bs, and thus not purely loosen | |
2938 | * restrictions. | |
2939 | */ | |
2940 | if (new_bs) { | |
74ad9a3b | 2941 | bdrv_set_perm(new_bs); |
87ace5f8 HR |
2942 | } |
2943 | ||
8ee03995 | 2944 | if (old_bs) { |
bb87e4d1 VSO |
2945 | /* |
2946 | * Update permissions for old node. We're just taking a parent away, so | |
2947 | * we're loosening restrictions. Errors of permission update are not | |
2948 | * fatal in this case, ignore them. | |
2949 | */ | |
071b474f | 2950 | bdrv_refresh_perms(old_bs, NULL); |
ad943dcb KW |
2951 | |
2952 | /* When the parent requiring a non-default AioContext is removed, the | |
2953 | * node moves back to the main AioContext */ | |
2954 | bdrv_try_set_aio_context(old_bs, qemu_get_aio_context(), NULL); | |
e9740bc6 | 2955 | } |
e9740bc6 KW |
2956 | } |
2957 | ||
548a74c0 | 2958 | static void bdrv_remove_empty_child(BdrvChild *child) |
df581792 | 2959 | { |
548a74c0 VSO |
2960 | assert(!child->bs); |
2961 | QLIST_SAFE_REMOVE(child, next); | |
2962 | g_free(child->name); | |
2963 | g_free(child); | |
2964 | } | |
d5e6f437 | 2965 | |
548a74c0 VSO |
2966 | typedef struct BdrvAttachChildCommonState { |
2967 | BdrvChild **child; | |
2968 | AioContext *old_parent_ctx; | |
2969 | AioContext *old_child_ctx; | |
2970 | } BdrvAttachChildCommonState; | |
2971 | ||
2972 | static void bdrv_attach_child_common_abort(void *opaque) | |
2973 | { | |
2974 | BdrvAttachChildCommonState *s = opaque; | |
2975 | BdrvChild *child = *s->child; | |
2976 | BlockDriverState *bs = child->bs; | |
2977 | ||
2978 | bdrv_replace_child_noperm(child, NULL); | |
2979 | ||
2980 | if (bdrv_get_aio_context(bs) != s->old_child_ctx) { | |
2981 | bdrv_try_set_aio_context(bs, s->old_child_ctx, &error_abort); | |
2982 | } | |
2983 | ||
2984 | if (bdrv_child_get_parent_aio_context(child) != s->old_parent_ctx) { | |
2985 | GSList *ignore = g_slist_prepend(NULL, child); | |
2986 | ||
2987 | child->klass->can_set_aio_ctx(child, s->old_parent_ctx, &ignore, | |
2988 | &error_abort); | |
2989 | g_slist_free(ignore); | |
2990 | ignore = g_slist_prepend(NULL, child); | |
2991 | child->klass->set_aio_ctx(child, s->old_parent_ctx, &ignore); | |
2992 | ||
2993 | g_slist_free(ignore); | |
d5e6f437 KW |
2994 | } |
2995 | ||
548a74c0 VSO |
2996 | bdrv_unref(bs); |
2997 | bdrv_remove_empty_child(child); | |
2998 | *s->child = NULL; | |
2999 | } | |
3000 | ||
3001 | static TransactionActionDrv bdrv_attach_child_common_drv = { | |
3002 | .abort = bdrv_attach_child_common_abort, | |
3003 | .clean = g_free, | |
3004 | }; | |
3005 | ||
3006 | /* | |
3007 | * Common part of attaching bdrv child to bs or to blk or to job | |
3008 | */ | |
3009 | static int bdrv_attach_child_common(BlockDriverState *child_bs, | |
3010 | const char *child_name, | |
3011 | const BdrvChildClass *child_class, | |
3012 | BdrvChildRole child_role, | |
3013 | uint64_t perm, uint64_t shared_perm, | |
3014 | void *opaque, BdrvChild **child, | |
3015 | Transaction *tran, Error **errp) | |
3016 | { | |
3017 | BdrvChild *new_child; | |
3018 | AioContext *parent_ctx; | |
3019 | AioContext *child_ctx = bdrv_get_aio_context(child_bs); | |
3020 | ||
3021 | assert(child); | |
3022 | assert(*child == NULL); | |
3023 | ||
3024 | new_child = g_new(BdrvChild, 1); | |
3025 | *new_child = (BdrvChild) { | |
d5e6f437 KW |
3026 | .bs = NULL, |
3027 | .name = g_strdup(child_name), | |
bd86fb99 | 3028 | .klass = child_class, |
258b7765 | 3029 | .role = child_role, |
d5e6f437 KW |
3030 | .perm = perm, |
3031 | .shared_perm = shared_perm, | |
3032 | .opaque = opaque, | |
df581792 KW |
3033 | }; |
3034 | ||
548a74c0 VSO |
3035 | /* |
3036 | * If the AioContexts don't match, first try to move the subtree of | |
132ada80 | 3037 | * child_bs into the AioContext of the new parent. If this doesn't work, |
548a74c0 VSO |
3038 | * try moving the parent into the AioContext of child_bs instead. |
3039 | */ | |
3040 | parent_ctx = bdrv_child_get_parent_aio_context(new_child); | |
3041 | if (child_ctx != parent_ctx) { | |
3042 | Error *local_err = NULL; | |
3043 | int ret = bdrv_try_set_aio_context(child_bs, parent_ctx, &local_err); | |
3044 | ||
bd86fb99 | 3045 | if (ret < 0 && child_class->can_set_aio_ctx) { |
548a74c0 VSO |
3046 | GSList *ignore = g_slist_prepend(NULL, new_child); |
3047 | if (child_class->can_set_aio_ctx(new_child, child_ctx, &ignore, | |
3048 | NULL)) | |
3049 | { | |
132ada80 KW |
3050 | error_free(local_err); |
3051 | ret = 0; | |
3052 | g_slist_free(ignore); | |
548a74c0 VSO |
3053 | ignore = g_slist_prepend(NULL, new_child); |
3054 | child_class->set_aio_ctx(new_child, child_ctx, &ignore); | |
132ada80 KW |
3055 | } |
3056 | g_slist_free(ignore); | |
3057 | } | |
548a74c0 | 3058 | |
132ada80 KW |
3059 | if (ret < 0) { |
3060 | error_propagate(errp, local_err); | |
548a74c0 VSO |
3061 | bdrv_remove_empty_child(new_child); |
3062 | return ret; | |
132ada80 KW |
3063 | } |
3064 | } | |
3065 | ||
548a74c0 VSO |
3066 | bdrv_ref(child_bs); |
3067 | bdrv_replace_child_noperm(new_child, child_bs); | |
3068 | ||
3069 | *child = new_child; | |
b4b059f6 | 3070 | |
548a74c0 VSO |
3071 | BdrvAttachChildCommonState *s = g_new(BdrvAttachChildCommonState, 1); |
3072 | *s = (BdrvAttachChildCommonState) { | |
3073 | .child = child, | |
3074 | .old_parent_ctx = parent_ctx, | |
3075 | .old_child_ctx = child_ctx, | |
3076 | }; | |
3077 | tran_add(tran, &bdrv_attach_child_common_drv, s); | |
3078 | ||
3079 | return 0; | |
3080 | } | |
3081 | ||
3082 | static void bdrv_detach_child(BdrvChild *child) | |
3083 | { | |
3084 | bdrv_replace_child(child, NULL); | |
3085 | bdrv_remove_empty_child(child); | |
3086 | } | |
3087 | ||
3088 | /* | |
3089 | * This function steals the reference to child_bs from the caller. | |
3090 | * That reference is later dropped by bdrv_root_unref_child(). | |
3091 | * | |
3092 | * On failure NULL is returned, errp is set and the reference to | |
3093 | * child_bs is also dropped. | |
3094 | * | |
3095 | * The caller must hold the AioContext lock @child_bs, but not that of @ctx | |
3096 | * (unless @child_bs is already in @ctx). | |
3097 | */ | |
3098 | BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, | |
3099 | const char *child_name, | |
3100 | const BdrvChildClass *child_class, | |
3101 | BdrvChildRole child_role, | |
3102 | uint64_t perm, uint64_t shared_perm, | |
3103 | void *opaque, Error **errp) | |
3104 | { | |
3105 | int ret; | |
3106 | BdrvChild *child = NULL; | |
3107 | Transaction *tran = tran_new(); | |
3108 | ||
3109 | ret = bdrv_attach_child_common(child_bs, child_name, child_class, | |
3110 | child_role, perm, shared_perm, opaque, | |
3111 | &child, tran, errp); | |
3112 | if (ret < 0) { | |
3113 | bdrv_unref(child_bs); | |
3114 | return NULL; | |
3115 | } | |
3116 | ||
3117 | ret = bdrv_refresh_perms(child_bs, errp); | |
3118 | tran_finalize(tran, ret); | |
3119 | ||
3120 | bdrv_unref(child_bs); | |
b4b059f6 | 3121 | return child; |
df581792 KW |
3122 | } |
3123 | ||
b441dc71 AG |
3124 | /* |
3125 | * This function transfers the reference to child_bs from the caller | |
3126 | * to parent_bs. That reference is later dropped by parent_bs on | |
3127 | * bdrv_close() or if someone calls bdrv_unref_child(). | |
3128 | * | |
3129 | * On failure NULL is returned, errp is set and the reference to | |
3130 | * child_bs is also dropped. | |
132ada80 KW |
3131 | * |
3132 | * If @parent_bs and @child_bs are in different AioContexts, the caller must | |
3133 | * hold the AioContext lock for @child_bs, but not for @parent_bs. | |
b441dc71 | 3134 | */ |
98292c61 WC |
3135 | BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, |
3136 | BlockDriverState *child_bs, | |
3137 | const char *child_name, | |
bd86fb99 | 3138 | const BdrvChildClass *child_class, |
258b7765 | 3139 | BdrvChildRole child_role, |
8b2ff529 | 3140 | Error **errp) |
f21d96d0 | 3141 | { |
d5e6f437 | 3142 | BdrvChild *child; |
f68c598b KW |
3143 | uint64_t perm, shared_perm; |
3144 | ||
3145 | bdrv_get_cumulative_perm(parent_bs, &perm, &shared_perm); | |
3146 | ||
3147 | assert(parent_bs->drv); | |
e5d8a406 | 3148 | bdrv_child_perm(parent_bs, child_bs, NULL, child_role, NULL, |
ffd1a5a2 | 3149 | perm, shared_perm, &perm, &shared_perm); |
d5e6f437 | 3150 | |
bd86fb99 | 3151 | child = bdrv_root_attach_child(child_bs, child_name, child_class, |
228ca37e VSO |
3152 | child_role, perm, shared_perm, parent_bs, |
3153 | errp); | |
d5e6f437 KW |
3154 | if (child == NULL) { |
3155 | return NULL; | |
3156 | } | |
3157 | ||
f21d96d0 KW |
3158 | QLIST_INSERT_HEAD(&parent_bs->children, child, next); |
3159 | return child; | |
3160 | } | |
3161 | ||
7b99a266 | 3162 | /* Callers must ensure that child->frozen is false. */ |
f21d96d0 | 3163 | void bdrv_root_unref_child(BdrvChild *child) |
33a60407 | 3164 | { |
779020cb KW |
3165 | BlockDriverState *child_bs; |
3166 | ||
f21d96d0 KW |
3167 | child_bs = child->bs; |
3168 | bdrv_detach_child(child); | |
3169 | bdrv_unref(child_bs); | |
3170 | } | |
3171 | ||
3cf746b3 HR |
3172 | /** |
3173 | * Clear all inherits_from pointers from children and grandchildren of | |
3174 | * @root that point to @root, where necessary. | |
3175 | */ | |
3176 | static void bdrv_unset_inherits_from(BlockDriverState *root, BdrvChild *child) | |
f21d96d0 | 3177 | { |
3cf746b3 | 3178 | BdrvChild *c; |
4e4bf5c4 | 3179 | |
3cf746b3 HR |
3180 | if (child->bs->inherits_from == root) { |
3181 | /* | |
3182 | * Remove inherits_from only when the last reference between root and | |
3183 | * child->bs goes away. | |
3184 | */ | |
3185 | QLIST_FOREACH(c, &root->children, next) { | |
4e4bf5c4 KW |
3186 | if (c != child && c->bs == child->bs) { |
3187 | break; | |
3188 | } | |
3189 | } | |
3190 | if (c == NULL) { | |
3191 | child->bs->inherits_from = NULL; | |
3192 | } | |
33a60407 KW |
3193 | } |
3194 | ||
3cf746b3 HR |
3195 | QLIST_FOREACH(c, &child->bs->children, next) { |
3196 | bdrv_unset_inherits_from(root, c); | |
3197 | } | |
3198 | } | |
3199 | ||
7b99a266 | 3200 | /* Callers must ensure that child->frozen is false. */ |
3cf746b3 HR |
3201 | void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child) |
3202 | { | |
3203 | if (child == NULL) { | |
3204 | return; | |
3205 | } | |
3206 | ||
3207 | bdrv_unset_inherits_from(parent, child); | |
f21d96d0 | 3208 | bdrv_root_unref_child(child); |
33a60407 KW |
3209 | } |
3210 | ||
5c8cab48 KW |
3211 | |
3212 | static void bdrv_parent_cb_change_media(BlockDriverState *bs, bool load) | |
3213 | { | |
3214 | BdrvChild *c; | |
3215 | QLIST_FOREACH(c, &bs->parents, next_parent) { | |
bd86fb99 HR |
3216 | if (c->klass->change_media) { |
3217 | c->klass->change_media(c, load); | |
5c8cab48 KW |
3218 | } |
3219 | } | |
3220 | } | |
3221 | ||
0065c455 AG |
3222 | /* Return true if you can reach parent going through child->inherits_from |
3223 | * recursively. If parent or child are NULL, return false */ | |
3224 | static bool bdrv_inherits_from_recursive(BlockDriverState *child, | |
3225 | BlockDriverState *parent) | |
3226 | { | |
3227 | while (child && child != parent) { | |
3228 | child = child->inherits_from; | |
3229 | } | |
3230 | ||
3231 | return child != NULL; | |
3232 | } | |
3233 | ||
25191e5f HR |
3234 | /* |
3235 | * Return the BdrvChildRole for @bs's backing child. bs->backing is | |
3236 | * mostly used for COW backing children (role = COW), but also for | |
3237 | * filtered children (role = FILTERED | PRIMARY). | |
3238 | */ | |
3239 | static BdrvChildRole bdrv_backing_role(BlockDriverState *bs) | |
3240 | { | |
3241 | if (bs->drv && bs->drv->is_filter) { | |
3242 | return BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY; | |
3243 | } else { | |
3244 | return BDRV_CHILD_COW; | |
3245 | } | |
3246 | } | |
3247 | ||
5db15a57 | 3248 | /* |
9ee413cb | 3249 | * Sets the bs->backing link of a BDS. A new reference is created; callers |
5db15a57 KW |
3250 | * which don't need their own reference any more must call bdrv_unref(). |
3251 | */ | |
a1e708fc VSO |
3252 | int bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, |
3253 | Error **errp) | |
8d24cce1 | 3254 | { |
a1e708fc | 3255 | int ret = 0; |
0065c455 AG |
3256 | bool update_inherits_from = bdrv_chain_contains(bs, backing_hd) && |
3257 | bdrv_inherits_from_recursive(backing_hd, bs); | |
3258 | ||
9ee413cb | 3259 | if (bdrv_is_backing_chain_frozen(bs, child_bs(bs->backing), errp)) { |
a1e708fc | 3260 | return -EPERM; |
2cad1ebe AG |
3261 | } |
3262 | ||
5db15a57 KW |
3263 | if (backing_hd) { |
3264 | bdrv_ref(backing_hd); | |
3265 | } | |
8d24cce1 | 3266 | |
760e0063 | 3267 | if (bs->backing) { |
7b99a266 | 3268 | /* Cannot be frozen, we checked that above */ |
5db15a57 | 3269 | bdrv_unref_child(bs, bs->backing); |
6e57963a | 3270 | bs->backing = NULL; |
826b6ca0 FZ |
3271 | } |
3272 | ||
8d24cce1 FZ |
3273 | if (!backing_hd) { |
3274 | goto out; | |
3275 | } | |
12fa4af6 | 3276 | |
25191e5f HR |
3277 | bs->backing = bdrv_attach_child(bs, backing_hd, "backing", &child_of_bds, |
3278 | bdrv_backing_role(bs), errp); | |
a1e708fc VSO |
3279 | if (!bs->backing) { |
3280 | ret = -EPERM; | |
3281 | goto out; | |
3282 | } | |
3283 | ||
0065c455 AG |
3284 | /* If backing_hd was already part of bs's backing chain, and |
3285 | * inherits_from pointed recursively to bs then let's update it to | |
3286 | * point directly to bs (else it will become NULL). */ | |
a1e708fc | 3287 | if (update_inherits_from) { |
0065c455 AG |
3288 | backing_hd->inherits_from = bs; |
3289 | } | |
826b6ca0 | 3290 | |
8d24cce1 | 3291 | out: |
3baca891 | 3292 | bdrv_refresh_limits(bs, NULL); |
a1e708fc VSO |
3293 | |
3294 | return ret; | |
8d24cce1 FZ |
3295 | } |
3296 | ||
31ca6d07 KW |
3297 | /* |
3298 | * Opens the backing file for a BlockDriverState if not yet open | |
3299 | * | |
d9b7b057 KW |
3300 | * bdref_key specifies the key for the image's BlockdevRef in the options QDict. |
3301 | * That QDict has to be flattened; therefore, if the BlockdevRef is a QDict | |
3302 | * itself, all options starting with "${bdref_key}." are considered part of the | |
3303 | * BlockdevRef. | |
3304 | * | |
3305 | * TODO Can this be unified with bdrv_open_image()? | |
31ca6d07 | 3306 | */ |
d9b7b057 KW |
3307 | int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, |
3308 | const char *bdref_key, Error **errp) | |
9156df12 | 3309 | { |
6b6833c1 | 3310 | char *backing_filename = NULL; |
d9b7b057 KW |
3311 | char *bdref_key_dot; |
3312 | const char *reference = NULL; | |
317fc44e | 3313 | int ret = 0; |
998c2019 | 3314 | bool implicit_backing = false; |
8d24cce1 | 3315 | BlockDriverState *backing_hd; |
d9b7b057 KW |
3316 | QDict *options; |
3317 | QDict *tmp_parent_options = NULL; | |
34b5d2c6 | 3318 | Error *local_err = NULL; |
9156df12 | 3319 | |
760e0063 | 3320 | if (bs->backing != NULL) { |
1ba4b6a5 | 3321 | goto free_exit; |
9156df12 PB |
3322 | } |
3323 | ||
31ca6d07 | 3324 | /* NULL means an empty set of options */ |
d9b7b057 KW |
3325 | if (parent_options == NULL) { |
3326 | tmp_parent_options = qdict_new(); | |
3327 | parent_options = tmp_parent_options; | |
31ca6d07 KW |
3328 | } |
3329 | ||
9156df12 | 3330 | bs->open_flags &= ~BDRV_O_NO_BACKING; |
d9b7b057 KW |
3331 | |
3332 | bdref_key_dot = g_strdup_printf("%s.", bdref_key); | |
3333 | qdict_extract_subqdict(parent_options, &options, bdref_key_dot); | |
3334 | g_free(bdref_key_dot); | |
3335 | ||
129c7d1c MA |
3336 | /* |
3337 | * Caution: while qdict_get_try_str() is fine, getting non-string | |
3338 | * types would require more care. When @parent_options come from | |
3339 | * -blockdev or blockdev_add, its members are typed according to | |
3340 | * the QAPI schema, but when they come from -drive, they're all | |
3341 | * QString. | |
3342 | */ | |
d9b7b057 KW |
3343 | reference = qdict_get_try_str(parent_options, bdref_key); |
3344 | if (reference || qdict_haskey(options, "file.filename")) { | |
6b6833c1 | 3345 | /* keep backing_filename NULL */ |
1cb6f506 | 3346 | } else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) { |
cb3e7f08 | 3347 | qobject_unref(options); |
1ba4b6a5 | 3348 | goto free_exit; |
dbecebdd | 3349 | } else { |
998c2019 HR |
3350 | if (qdict_size(options) == 0) { |
3351 | /* If the user specifies options that do not modify the | |
3352 | * backing file's behavior, we might still consider it the | |
3353 | * implicit backing file. But it's easier this way, and | |
3354 | * just specifying some of the backing BDS's options is | |
3355 | * only possible with -drive anyway (otherwise the QAPI | |
3356 | * schema forces the user to specify everything). */ | |
3357 | implicit_backing = !strcmp(bs->auto_backing_file, bs->backing_file); | |
3358 | } | |
3359 | ||
6b6833c1 | 3360 | backing_filename = bdrv_get_full_backing_filename(bs, &local_err); |
9f07429e HR |
3361 | if (local_err) { |
3362 | ret = -EINVAL; | |
3363 | error_propagate(errp, local_err); | |
cb3e7f08 | 3364 | qobject_unref(options); |
9f07429e HR |
3365 | goto free_exit; |
3366 | } | |
9156df12 PB |
3367 | } |
3368 | ||
8ee79e70 KW |
3369 | if (!bs->drv || !bs->drv->supports_backing) { |
3370 | ret = -EINVAL; | |
3371 | error_setg(errp, "Driver doesn't support backing files"); | |
cb3e7f08 | 3372 | qobject_unref(options); |
8ee79e70 KW |
3373 | goto free_exit; |
3374 | } | |
3375 | ||
6bff597b PK |
3376 | if (!reference && |
3377 | bs->backing_format[0] != '\0' && !qdict_haskey(options, "driver")) { | |
46f5ac20 | 3378 | qdict_put_str(options, "driver", bs->backing_format); |
9156df12 PB |
3379 | } |
3380 | ||
6b6833c1 | 3381 | backing_hd = bdrv_open_inherit(backing_filename, reference, options, 0, bs, |
25191e5f | 3382 | &child_of_bds, bdrv_backing_role(bs), errp); |
5b363937 | 3383 | if (!backing_hd) { |
9156df12 | 3384 | bs->open_flags |= BDRV_O_NO_BACKING; |
e43bfd9c | 3385 | error_prepend(errp, "Could not open backing file: "); |
5b363937 | 3386 | ret = -EINVAL; |
1ba4b6a5 | 3387 | goto free_exit; |
9156df12 | 3388 | } |
df581792 | 3389 | |
998c2019 HR |
3390 | if (implicit_backing) { |
3391 | bdrv_refresh_filename(backing_hd); | |
3392 | pstrcpy(bs->auto_backing_file, sizeof(bs->auto_backing_file), | |
3393 | backing_hd->filename); | |
3394 | } | |
3395 | ||
5db15a57 KW |
3396 | /* Hook up the backing file link; drop our reference, bs owns the |
3397 | * backing_hd reference now */ | |
dc9c10a1 | 3398 | ret = bdrv_set_backing_hd(bs, backing_hd, errp); |
5db15a57 | 3399 | bdrv_unref(backing_hd); |
dc9c10a1 | 3400 | if (ret < 0) { |
12fa4af6 KW |
3401 | goto free_exit; |
3402 | } | |
d80ac658 | 3403 | |
d9b7b057 KW |
3404 | qdict_del(parent_options, bdref_key); |
3405 | ||
1ba4b6a5 BC |
3406 | free_exit: |
3407 | g_free(backing_filename); | |
cb3e7f08 | 3408 | qobject_unref(tmp_parent_options); |
1ba4b6a5 | 3409 | return ret; |
9156df12 PB |
3410 | } |
3411 | ||
2d6b86af KW |
3412 | static BlockDriverState * |
3413 | bdrv_open_child_bs(const char *filename, QDict *options, const char *bdref_key, | |
bd86fb99 | 3414 | BlockDriverState *parent, const BdrvChildClass *child_class, |
272c02ea | 3415 | BdrvChildRole child_role, bool allow_none, Error **errp) |
da557aac | 3416 | { |
2d6b86af | 3417 | BlockDriverState *bs = NULL; |
da557aac | 3418 | QDict *image_options; |
da557aac HR |
3419 | char *bdref_key_dot; |
3420 | const char *reference; | |
3421 | ||
bd86fb99 | 3422 | assert(child_class != NULL); |
f67503e5 | 3423 | |
da557aac HR |
3424 | bdref_key_dot = g_strdup_printf("%s.", bdref_key); |
3425 | qdict_extract_subqdict(options, &image_options, bdref_key_dot); | |
3426 | g_free(bdref_key_dot); | |
3427 | ||
129c7d1c MA |
3428 | /* |
3429 | * Caution: while qdict_get_try_str() is fine, getting non-string | |
3430 | * types would require more care. When @options come from | |
3431 | * -blockdev or blockdev_add, its members are typed according to | |
3432 | * the QAPI schema, but when they come from -drive, they're all | |
3433 | * QString. | |
3434 | */ | |
da557aac HR |
3435 | reference = qdict_get_try_str(options, bdref_key); |
3436 | if (!filename && !reference && !qdict_size(image_options)) { | |
b4b059f6 | 3437 | if (!allow_none) { |
da557aac HR |
3438 | error_setg(errp, "A block device must be specified for \"%s\"", |
3439 | bdref_key); | |
da557aac | 3440 | } |
cb3e7f08 | 3441 | qobject_unref(image_options); |
da557aac HR |
3442 | goto done; |
3443 | } | |
3444 | ||
5b363937 | 3445 | bs = bdrv_open_inherit(filename, reference, image_options, 0, |
272c02ea | 3446 | parent, child_class, child_role, errp); |
5b363937 | 3447 | if (!bs) { |
df581792 KW |
3448 | goto done; |
3449 | } | |
3450 | ||
da557aac HR |
3451 | done: |
3452 | qdict_del(options, bdref_key); | |
2d6b86af KW |
3453 | return bs; |
3454 | } | |
3455 | ||
3456 | /* | |
3457 | * Opens a disk image whose options are given as BlockdevRef in another block | |
3458 | * device's options. | |
3459 | * | |
3460 | * If allow_none is true, no image will be opened if filename is false and no | |
3461 | * BlockdevRef is given. NULL will be returned, but errp remains unset. | |
3462 | * | |
3463 | * bdrev_key specifies the key for the image's BlockdevRef in the options QDict. | |
3464 | * That QDict has to be flattened; therefore, if the BlockdevRef is a QDict | |
3465 | * itself, all options starting with "${bdref_key}." are considered part of the | |
3466 | * BlockdevRef. | |
3467 | * | |
3468 | * The BlockdevRef will be removed from the options QDict. | |
3469 | */ | |
3470 | BdrvChild *bdrv_open_child(const char *filename, | |
3471 | QDict *options, const char *bdref_key, | |
3472 | BlockDriverState *parent, | |
bd86fb99 | 3473 | const BdrvChildClass *child_class, |
258b7765 | 3474 | BdrvChildRole child_role, |
2d6b86af KW |
3475 | bool allow_none, Error **errp) |
3476 | { | |
3477 | BlockDriverState *bs; | |
3478 | ||
bd86fb99 | 3479 | bs = bdrv_open_child_bs(filename, options, bdref_key, parent, child_class, |
272c02ea | 3480 | child_role, allow_none, errp); |
2d6b86af KW |
3481 | if (bs == NULL) { |
3482 | return NULL; | |
3483 | } | |
3484 | ||
258b7765 HR |
3485 | return bdrv_attach_child(parent, bs, bdref_key, child_class, child_role, |
3486 | errp); | |
b4b059f6 KW |
3487 | } |
3488 | ||
bd86fb99 HR |
3489 | /* |
3490 | * TODO Future callers may need to specify parent/child_class in order for | |
3491 | * option inheritance to work. Existing callers use it for the root node. | |
3492 | */ | |
e1d74bc6 KW |
3493 | BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp) |
3494 | { | |
3495 | BlockDriverState *bs = NULL; | |
e1d74bc6 KW |
3496 | QObject *obj = NULL; |
3497 | QDict *qdict = NULL; | |
3498 | const char *reference = NULL; | |
3499 | Visitor *v = NULL; | |
3500 | ||
3501 | if (ref->type == QTYPE_QSTRING) { | |
3502 | reference = ref->u.reference; | |
3503 | } else { | |
3504 | BlockdevOptions *options = &ref->u.definition; | |
3505 | assert(ref->type == QTYPE_QDICT); | |
3506 | ||
3507 | v = qobject_output_visitor_new(&obj); | |
1f584248 | 3508 | visit_type_BlockdevOptions(v, NULL, &options, &error_abort); |
e1d74bc6 KW |
3509 | visit_complete(v, &obj); |
3510 | ||
7dc847eb | 3511 | qdict = qobject_to(QDict, obj); |
e1d74bc6 KW |
3512 | qdict_flatten(qdict); |
3513 | ||
3514 | /* bdrv_open_inherit() defaults to the values in bdrv_flags (for | |
3515 | * compatibility with other callers) rather than what we want as the | |
3516 | * real defaults. Apply the defaults here instead. */ | |
3517 | qdict_set_default_str(qdict, BDRV_OPT_CACHE_DIRECT, "off"); | |
3518 | qdict_set_default_str(qdict, BDRV_OPT_CACHE_NO_FLUSH, "off"); | |
3519 | qdict_set_default_str(qdict, BDRV_OPT_READ_ONLY, "off"); | |
e35bdc12 KW |
3520 | qdict_set_default_str(qdict, BDRV_OPT_AUTO_READ_ONLY, "off"); |
3521 | ||
e1d74bc6 KW |
3522 | } |
3523 | ||
272c02ea | 3524 | bs = bdrv_open_inherit(NULL, reference, qdict, 0, NULL, NULL, 0, errp); |
e1d74bc6 | 3525 | obj = NULL; |
cb3e7f08 | 3526 | qobject_unref(obj); |
e1d74bc6 KW |
3527 | visit_free(v); |
3528 | return bs; | |
3529 | } | |
3530 | ||
66836189 HR |
3531 | static BlockDriverState *bdrv_append_temp_snapshot(BlockDriverState *bs, |
3532 | int flags, | |
3533 | QDict *snapshot_options, | |
3534 | Error **errp) | |
b998875d KW |
3535 | { |
3536 | /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */ | |
1ba4b6a5 | 3537 | char *tmp_filename = g_malloc0(PATH_MAX + 1); |
b998875d | 3538 | int64_t total_size; |
83d0521a | 3539 | QemuOpts *opts = NULL; |
ff6ed714 | 3540 | BlockDriverState *bs_snapshot = NULL; |
b998875d KW |
3541 | int ret; |
3542 | ||
3543 | /* if snapshot, we create a temporary backing file and open it | |
3544 | instead of opening 'filename' directly */ | |
3545 | ||
3546 | /* Get the required size from the image */ | |
f187743a KW |
3547 | total_size = bdrv_getlength(bs); |
3548 | if (total_size < 0) { | |
3549 | error_setg_errno(errp, -total_size, "Could not get image size"); | |
1ba4b6a5 | 3550 | goto out; |
f187743a | 3551 | } |
b998875d KW |
3552 | |
3553 | /* Create the temporary image */ | |
1ba4b6a5 | 3554 | ret = get_tmp_filename(tmp_filename, PATH_MAX + 1); |
b998875d KW |
3555 | if (ret < 0) { |
3556 | error_setg_errno(errp, -ret, "Could not get temporary filename"); | |
1ba4b6a5 | 3557 | goto out; |
b998875d KW |
3558 | } |
3559 | ||
ef810437 | 3560 | opts = qemu_opts_create(bdrv_qcow2.create_opts, NULL, 0, |
c282e1fd | 3561 | &error_abort); |
39101f25 | 3562 | qemu_opt_set_number(opts, BLOCK_OPT_SIZE, total_size, &error_abort); |
e43bfd9c | 3563 | ret = bdrv_create(&bdrv_qcow2, tmp_filename, opts, errp); |
83d0521a | 3564 | qemu_opts_del(opts); |
b998875d | 3565 | if (ret < 0) { |
e43bfd9c MA |
3566 | error_prepend(errp, "Could not create temporary overlay '%s': ", |
3567 | tmp_filename); | |
1ba4b6a5 | 3568 | goto out; |
b998875d KW |
3569 | } |
3570 | ||
73176bee | 3571 | /* Prepare options QDict for the temporary file */ |
46f5ac20 EB |
3572 | qdict_put_str(snapshot_options, "file.driver", "file"); |
3573 | qdict_put_str(snapshot_options, "file.filename", tmp_filename); | |
3574 | qdict_put_str(snapshot_options, "driver", "qcow2"); | |
b998875d | 3575 | |
5b363937 | 3576 | bs_snapshot = bdrv_open(NULL, NULL, snapshot_options, flags, errp); |
73176bee | 3577 | snapshot_options = NULL; |
5b363937 | 3578 | if (!bs_snapshot) { |
1ba4b6a5 | 3579 | goto out; |
b998875d KW |
3580 | } |
3581 | ||
934aee14 VSO |
3582 | ret = bdrv_append(bs_snapshot, bs, errp); |
3583 | if (ret < 0) { | |
ff6ed714 | 3584 | bs_snapshot = NULL; |
b2c2832c KW |
3585 | goto out; |
3586 | } | |
1ba4b6a5 BC |
3587 | |
3588 | out: | |
cb3e7f08 | 3589 | qobject_unref(snapshot_options); |
1ba4b6a5 | 3590 | g_free(tmp_filename); |
ff6ed714 | 3591 | return bs_snapshot; |
b998875d KW |
3592 | } |
3593 | ||
b6ce07aa KW |
3594 | /* |
3595 | * Opens a disk image (raw, qcow2, vmdk, ...) | |
de9c0cec KW |
3596 | * |
3597 | * options is a QDict of options to pass to the block drivers, or NULL for an | |
3598 | * empty set of options. The reference to the QDict belongs to the block layer | |
3599 | * after the call (even on failure), so if the caller intends to reuse the | |
cb3e7f08 | 3600 | * dictionary, it needs to use qobject_ref() before calling bdrv_open. |
f67503e5 HR |
3601 | * |
3602 | * If *pbs is NULL, a new BDS will be created with a pointer to it stored there. | |
3603 | * If it is not NULL, the referenced BDS will be reused. | |
ddf5636d HR |
3604 | * |
3605 | * The reference parameter may be used to specify an existing block device which | |
3606 | * should be opened. If specified, neither options nor a filename may be given, | |
3607 | * nor can an existing BDS be reused (that is, *pbs has to be NULL). | |
b6ce07aa | 3608 | */ |
5b363937 HR |
3609 | static BlockDriverState *bdrv_open_inherit(const char *filename, |
3610 | const char *reference, | |
3611 | QDict *options, int flags, | |
3612 | BlockDriverState *parent, | |
bd86fb99 | 3613 | const BdrvChildClass *child_class, |
272c02ea | 3614 | BdrvChildRole child_role, |
5b363937 | 3615 | Error **errp) |
ea2384d3 | 3616 | { |
b6ce07aa | 3617 | int ret; |
5696c6e3 | 3618 | BlockBackend *file = NULL; |
9a4f4c31 | 3619 | BlockDriverState *bs; |
ce343771 | 3620 | BlockDriver *drv = NULL; |
2f624b80 | 3621 | BdrvChild *child; |
74fe54f2 | 3622 | const char *drvname; |
3e8c2e57 | 3623 | const char *backing; |
34b5d2c6 | 3624 | Error *local_err = NULL; |
73176bee | 3625 | QDict *snapshot_options = NULL; |
b1e6fc08 | 3626 | int snapshot_flags = 0; |
712e7874 | 3627 | |
bd86fb99 HR |
3628 | assert(!child_class || !flags); |
3629 | assert(!child_class == !parent); | |
f67503e5 | 3630 | |
ddf5636d HR |
3631 | if (reference) { |
3632 | bool options_non_empty = options ? qdict_size(options) : false; | |
cb3e7f08 | 3633 | qobject_unref(options); |
ddf5636d | 3634 | |
ddf5636d HR |
3635 | if (filename || options_non_empty) { |
3636 | error_setg(errp, "Cannot reference an existing block device with " | |
3637 | "additional options or a new filename"); | |
5b363937 | 3638 | return NULL; |
ddf5636d HR |
3639 | } |
3640 | ||
3641 | bs = bdrv_lookup_bs(reference, reference, errp); | |
3642 | if (!bs) { | |
5b363937 | 3643 | return NULL; |
ddf5636d | 3644 | } |
76b22320 | 3645 | |
ddf5636d | 3646 | bdrv_ref(bs); |
5b363937 | 3647 | return bs; |
ddf5636d HR |
3648 | } |
3649 | ||
5b363937 | 3650 | bs = bdrv_new(); |
f67503e5 | 3651 | |
de9c0cec KW |
3652 | /* NULL means an empty set of options */ |
3653 | if (options == NULL) { | |
3654 | options = qdict_new(); | |
3655 | } | |
3656 | ||
145f598e | 3657 | /* json: syntax counts as explicit options, as if in the QDict */ |
de3b53f0 KW |
3658 | parse_json_protocol(options, &filename, &local_err); |
3659 | if (local_err) { | |
de3b53f0 KW |
3660 | goto fail; |
3661 | } | |
3662 | ||
145f598e KW |
3663 | bs->explicit_options = qdict_clone_shallow(options); |
3664 | ||
bd86fb99 | 3665 | if (child_class) { |
3cdc69d3 HR |
3666 | bool parent_is_format; |
3667 | ||
3668 | if (parent->drv) { | |
3669 | parent_is_format = parent->drv->is_format; | |
3670 | } else { | |
3671 | /* | |
3672 | * parent->drv is not set yet because this node is opened for | |
3673 | * (potential) format probing. That means that @parent is going | |
3674 | * to be a format node. | |
3675 | */ | |
3676 | parent_is_format = true; | |
3677 | } | |
3678 | ||
bddcec37 | 3679 | bs->inherits_from = parent; |
3cdc69d3 HR |
3680 | child_class->inherit_options(child_role, parent_is_format, |
3681 | &flags, options, | |
bd86fb99 | 3682 | parent->open_flags, parent->options); |
f3930ed0 KW |
3683 | } |
3684 | ||
de3b53f0 | 3685 | ret = bdrv_fill_options(&options, filename, &flags, &local_err); |
dfde483e | 3686 | if (ret < 0) { |
462f5bcf KW |
3687 | goto fail; |
3688 | } | |
3689 | ||
129c7d1c MA |
3690 | /* |
3691 | * Set the BDRV_O_RDWR and BDRV_O_ALLOW_RDWR flags. | |
3692 | * Caution: getting a boolean member of @options requires care. | |
3693 | * When @options come from -blockdev or blockdev_add, members are | |
3694 | * typed according to the QAPI schema, but when they come from | |
3695 | * -drive, they're all QString. | |
3696 | */ | |
f87a0e29 AG |
3697 | if (g_strcmp0(qdict_get_try_str(options, BDRV_OPT_READ_ONLY), "on") && |
3698 | !qdict_get_try_bool(options, BDRV_OPT_READ_ONLY, false)) { | |
3699 | flags |= (BDRV_O_RDWR | BDRV_O_ALLOW_RDWR); | |
3700 | } else { | |
3701 | flags &= ~BDRV_O_RDWR; | |
14499ea5 AG |
3702 | } |
3703 | ||
3704 | if (flags & BDRV_O_SNAPSHOT) { | |
3705 | snapshot_options = qdict_new(); | |
3706 | bdrv_temp_snapshot_options(&snapshot_flags, snapshot_options, | |
3707 | flags, options); | |
f87a0e29 AG |
3708 | /* Let bdrv_backing_options() override "read-only" */ |
3709 | qdict_del(options, BDRV_OPT_READ_ONLY); | |
00ff7ffd HR |
3710 | bdrv_inherited_options(BDRV_CHILD_COW, true, |
3711 | &flags, options, flags, options); | |
14499ea5 AG |
3712 | } |
3713 | ||
62392ebb KW |
3714 | bs->open_flags = flags; |
3715 | bs->options = options; | |
3716 | options = qdict_clone_shallow(options); | |
3717 | ||
76c591b0 | 3718 | /* Find the right image format driver */ |
129c7d1c | 3719 | /* See cautionary note on accessing @options above */ |
76c591b0 KW |
3720 | drvname = qdict_get_try_str(options, "driver"); |
3721 | if (drvname) { | |
3722 | drv = bdrv_find_format(drvname); | |
76c591b0 KW |
3723 | if (!drv) { |
3724 | error_setg(errp, "Unknown driver: '%s'", drvname); | |
76c591b0 KW |
3725 | goto fail; |
3726 | } | |
3727 | } | |
3728 | ||
3729 | assert(drvname || !(flags & BDRV_O_PROTOCOL)); | |
76c591b0 | 3730 | |
129c7d1c | 3731 | /* See cautionary note on accessing @options above */ |
3e8c2e57 | 3732 | backing = qdict_get_try_str(options, "backing"); |
e59a0cf1 HR |
3733 | if (qobject_to(QNull, qdict_get(options, "backing")) != NULL || |
3734 | (backing && *backing == '\0')) | |
3735 | { | |
4f7be280 HR |
3736 | if (backing) { |
3737 | warn_report("Use of \"backing\": \"\" is deprecated; " | |
3738 | "use \"backing\": null instead"); | |
3739 | } | |
3e8c2e57 | 3740 | flags |= BDRV_O_NO_BACKING; |
ae0f57f0 KW |
3741 | qdict_del(bs->explicit_options, "backing"); |
3742 | qdict_del(bs->options, "backing"); | |
3e8c2e57 AG |
3743 | qdict_del(options, "backing"); |
3744 | } | |
3745 | ||
5696c6e3 | 3746 | /* Open image file without format layer. This BlockBackend is only used for |
4e4bf5c4 KW |
3747 | * probing, the block drivers will do their own bdrv_open_child() for the |
3748 | * same BDS, which is why we put the node name back into options. */ | |
f4788adc | 3749 | if ((flags & BDRV_O_PROTOCOL) == 0) { |
5696c6e3 KW |
3750 | BlockDriverState *file_bs; |
3751 | ||
3752 | file_bs = bdrv_open_child_bs(filename, options, "file", bs, | |
58944401 HR |
3753 | &child_of_bds, BDRV_CHILD_IMAGE, |
3754 | true, &local_err); | |
1fdd6933 | 3755 | if (local_err) { |
f4788adc KW |
3756 | goto fail; |
3757 | } | |
5696c6e3 | 3758 | if (file_bs != NULL) { |
dacaa162 KW |
3759 | /* Not requesting BLK_PERM_CONSISTENT_READ because we're only |
3760 | * looking at the header to guess the image format. This works even | |
3761 | * in cases where a guest would not see a consistent state. */ | |
d861ab3a | 3762 | file = blk_new(bdrv_get_aio_context(file_bs), 0, BLK_PERM_ALL); |
d7086422 | 3763 | blk_insert_bs(file, file_bs, &local_err); |
5696c6e3 | 3764 | bdrv_unref(file_bs); |
d7086422 KW |
3765 | if (local_err) { |
3766 | goto fail; | |
3767 | } | |
5696c6e3 | 3768 | |
46f5ac20 | 3769 | qdict_put_str(options, "file", bdrv_get_node_name(file_bs)); |
4e4bf5c4 | 3770 | } |
f500a6d3 KW |
3771 | } |
3772 | ||
76c591b0 | 3773 | /* Image format probing */ |
38f3ef57 | 3774 | bs->probed = !drv; |
76c591b0 | 3775 | if (!drv && file) { |
cf2ab8fc | 3776 | ret = find_image_format(file, filename, &drv, &local_err); |
17b005f1 | 3777 | if (ret < 0) { |
8bfea15d | 3778 | goto fail; |
2a05cbe4 | 3779 | } |
62392ebb KW |
3780 | /* |
3781 | * This option update would logically belong in bdrv_fill_options(), | |
3782 | * but we first need to open bs->file for the probing to work, while | |
3783 | * opening bs->file already requires the (mostly) final set of options | |
3784 | * so that cache mode etc. can be inherited. | |
3785 | * | |
3786 | * Adding the driver later is somewhat ugly, but it's not an option | |
3787 | * that would ever be inherited, so it's correct. We just need to make | |
3788 | * sure to update both bs->options (which has the full effective | |
3789 | * options for bs) and options (which has file.* already removed). | |
3790 | */ | |
46f5ac20 EB |
3791 | qdict_put_str(bs->options, "driver", drv->format_name); |
3792 | qdict_put_str(options, "driver", drv->format_name); | |
76c591b0 | 3793 | } else if (!drv) { |
17b005f1 | 3794 | error_setg(errp, "Must specify either driver or file"); |
8bfea15d | 3795 | goto fail; |
ea2384d3 | 3796 | } |
b6ce07aa | 3797 | |
53a29513 HR |
3798 | /* BDRV_O_PROTOCOL must be set iff a protocol BDS is about to be created */ |
3799 | assert(!!(flags & BDRV_O_PROTOCOL) == !!drv->bdrv_file_open); | |
3800 | /* file must be NULL if a protocol BDS is about to be created | |
3801 | * (the inverse results in an error message from bdrv_open_common()) */ | |
3802 | assert(!(flags & BDRV_O_PROTOCOL) || !file); | |
3803 | ||
b6ce07aa | 3804 | /* Open the image */ |
82dc8b41 | 3805 | ret = bdrv_open_common(bs, file, options, &local_err); |
b6ce07aa | 3806 | if (ret < 0) { |
8bfea15d | 3807 | goto fail; |
6987307c CH |
3808 | } |
3809 | ||
4e4bf5c4 | 3810 | if (file) { |
5696c6e3 | 3811 | blk_unref(file); |
f500a6d3 KW |
3812 | file = NULL; |
3813 | } | |
3814 | ||
b6ce07aa | 3815 | /* If there is a backing file, use it */ |
9156df12 | 3816 | if ((flags & BDRV_O_NO_BACKING) == 0) { |
d9b7b057 | 3817 | ret = bdrv_open_backing_file(bs, options, "backing", &local_err); |
b6ce07aa | 3818 | if (ret < 0) { |
b6ad491a | 3819 | goto close_and_fail; |
b6ce07aa | 3820 | } |
b6ce07aa KW |
3821 | } |
3822 | ||
50196d7a AG |
3823 | /* Remove all children options and references |
3824 | * from bs->options and bs->explicit_options */ | |
2f624b80 AG |
3825 | QLIST_FOREACH(child, &bs->children, next) { |
3826 | char *child_key_dot; | |
3827 | child_key_dot = g_strdup_printf("%s.", child->name); | |
3828 | qdict_extract_subqdict(bs->explicit_options, NULL, child_key_dot); | |
3829 | qdict_extract_subqdict(bs->options, NULL, child_key_dot); | |
50196d7a AG |
3830 | qdict_del(bs->explicit_options, child->name); |
3831 | qdict_del(bs->options, child->name); | |
2f624b80 AG |
3832 | g_free(child_key_dot); |
3833 | } | |
3834 | ||
b6ad491a | 3835 | /* Check if any unknown options were used */ |
7ad2757f | 3836 | if (qdict_size(options) != 0) { |
b6ad491a | 3837 | const QDictEntry *entry = qdict_first(options); |
5acd9d81 HR |
3838 | if (flags & BDRV_O_PROTOCOL) { |
3839 | error_setg(errp, "Block protocol '%s' doesn't support the option " | |
3840 | "'%s'", drv->format_name, entry->key); | |
3841 | } else { | |
d0e46a55 HR |
3842 | error_setg(errp, |
3843 | "Block format '%s' does not support the option '%s'", | |
3844 | drv->format_name, entry->key); | |
5acd9d81 | 3845 | } |
b6ad491a | 3846 | |
b6ad491a KW |
3847 | goto close_and_fail; |
3848 | } | |
b6ad491a | 3849 | |
c01c214b | 3850 | bdrv_parent_cb_change_media(bs, true); |
b6ce07aa | 3851 | |
cb3e7f08 | 3852 | qobject_unref(options); |
8961be33 | 3853 | options = NULL; |
dd62f1ca KW |
3854 | |
3855 | /* For snapshot=on, create a temporary qcow2 overlay. bs points to the | |
3856 | * temporary snapshot afterwards. */ | |
3857 | if (snapshot_flags) { | |
66836189 HR |
3858 | BlockDriverState *snapshot_bs; |
3859 | snapshot_bs = bdrv_append_temp_snapshot(bs, snapshot_flags, | |
3860 | snapshot_options, &local_err); | |
73176bee | 3861 | snapshot_options = NULL; |
dd62f1ca KW |
3862 | if (local_err) { |
3863 | goto close_and_fail; | |
3864 | } | |
5b363937 HR |
3865 | /* We are not going to return bs but the overlay on top of it |
3866 | * (snapshot_bs); thus, we have to drop the strong reference to bs | |
3867 | * (which we obtained by calling bdrv_new()). bs will not be deleted, | |
3868 | * though, because the overlay still has a reference to it. */ | |
3869 | bdrv_unref(bs); | |
3870 | bs = snapshot_bs; | |
dd62f1ca KW |
3871 | } |
3872 | ||
5b363937 | 3873 | return bs; |
b6ce07aa | 3874 | |
8bfea15d | 3875 | fail: |
5696c6e3 | 3876 | blk_unref(file); |
cb3e7f08 MAL |
3877 | qobject_unref(snapshot_options); |
3878 | qobject_unref(bs->explicit_options); | |
3879 | qobject_unref(bs->options); | |
3880 | qobject_unref(options); | |
de9c0cec | 3881 | bs->options = NULL; |
998cbd6a | 3882 | bs->explicit_options = NULL; |
5b363937 | 3883 | bdrv_unref(bs); |
621ff94d | 3884 | error_propagate(errp, local_err); |
5b363937 | 3885 | return NULL; |
de9c0cec | 3886 | |
b6ad491a | 3887 | close_and_fail: |
5b363937 | 3888 | bdrv_unref(bs); |
cb3e7f08 MAL |
3889 | qobject_unref(snapshot_options); |
3890 | qobject_unref(options); | |
621ff94d | 3891 | error_propagate(errp, local_err); |
5b363937 | 3892 | return NULL; |
b6ce07aa KW |
3893 | } |
3894 | ||
5b363937 HR |
3895 | BlockDriverState *bdrv_open(const char *filename, const char *reference, |
3896 | QDict *options, int flags, Error **errp) | |
f3930ed0 | 3897 | { |
5b363937 | 3898 | return bdrv_open_inherit(filename, reference, options, flags, NULL, |
272c02ea | 3899 | NULL, 0, errp); |
f3930ed0 KW |
3900 | } |
3901 | ||
faf116b4 AG |
3902 | /* Return true if the NULL-terminated @list contains @str */ |
3903 | static bool is_str_in_list(const char *str, const char *const *list) | |
3904 | { | |
3905 | if (str && list) { | |
3906 | int i; | |
3907 | for (i = 0; list[i] != NULL; i++) { | |
3908 | if (!strcmp(str, list[i])) { | |
3909 | return true; | |
3910 | } | |
3911 | } | |
3912 | } | |
3913 | return false; | |
3914 | } | |
3915 | ||
3916 | /* | |
3917 | * Check that every option set in @bs->options is also set in | |
3918 | * @new_opts. | |
3919 | * | |
3920 | * Options listed in the common_options list and in | |
3921 | * @bs->drv->mutable_opts are skipped. | |
3922 | * | |
3923 | * Return 0 on success, otherwise return -EINVAL and set @errp. | |
3924 | */ | |
3925 | static int bdrv_reset_options_allowed(BlockDriverState *bs, | |
3926 | const QDict *new_opts, Error **errp) | |
3927 | { | |
3928 | const QDictEntry *e; | |
3929 | /* These options are common to all block drivers and are handled | |
3930 | * in bdrv_reopen_prepare() so they can be left out of @new_opts */ | |
3931 | const char *const common_options[] = { | |
3932 | "node-name", "discard", "cache.direct", "cache.no-flush", | |
3933 | "read-only", "auto-read-only", "detect-zeroes", NULL | |
3934 | }; | |
3935 | ||
3936 | for (e = qdict_first(bs->options); e; e = qdict_next(bs->options, e)) { | |
3937 | if (!qdict_haskey(new_opts, e->key) && | |
3938 | !is_str_in_list(e->key, common_options) && | |
3939 | !is_str_in_list(e->key, bs->drv->mutable_opts)) { | |
3940 | error_setg(errp, "Option '%s' cannot be reset " | |
3941 | "to its default value", e->key); | |
3942 | return -EINVAL; | |
3943 | } | |
3944 | } | |
3945 | ||
3946 | return 0; | |
3947 | } | |
3948 | ||
cb828c31 AG |
3949 | /* |
3950 | * Returns true if @child can be reached recursively from @bs | |
3951 | */ | |
3952 | static bool bdrv_recurse_has_child(BlockDriverState *bs, | |
3953 | BlockDriverState *child) | |
3954 | { | |
3955 | BdrvChild *c; | |
3956 | ||
3957 | if (bs == child) { | |
3958 | return true; | |
3959 | } | |
3960 | ||
3961 | QLIST_FOREACH(c, &bs->children, next) { | |
3962 | if (bdrv_recurse_has_child(c->bs, child)) { | |
3963 | return true; | |
3964 | } | |
3965 | } | |
3966 | ||
3967 | return false; | |
3968 | } | |
3969 | ||
e971aa12 JC |
3970 | /* |
3971 | * Adds a BlockDriverState to a simple queue for an atomic, transactional | |
3972 | * reopen of multiple devices. | |
3973 | * | |
859443b0 | 3974 | * bs_queue can either be an existing BlockReopenQueue that has had QTAILQ_INIT |
e971aa12 JC |
3975 | * already performed, or alternatively may be NULL a new BlockReopenQueue will |
3976 | * be created and initialized. This newly created BlockReopenQueue should be | |
3977 | * passed back in for subsequent calls that are intended to be of the same | |
3978 | * atomic 'set'. | |
3979 | * | |
3980 | * bs is the BlockDriverState to add to the reopen queue. | |
3981 | * | |
4d2cb092 KW |
3982 | * options contains the changed options for the associated bs |
3983 | * (the BlockReopenQueue takes ownership) | |
3984 | * | |
e971aa12 JC |
3985 | * flags contains the open flags for the associated bs |
3986 | * | |
3987 | * returns a pointer to bs_queue, which is either the newly allocated | |
3988 | * bs_queue, or the existing bs_queue being used. | |
3989 | * | |
1a63a907 | 3990 | * bs must be drained between bdrv_reopen_queue() and bdrv_reopen_multiple(). |
e971aa12 | 3991 | */ |
28518102 KW |
3992 | static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue, |
3993 | BlockDriverState *bs, | |
3994 | QDict *options, | |
bd86fb99 | 3995 | const BdrvChildClass *klass, |
272c02ea | 3996 | BdrvChildRole role, |
3cdc69d3 | 3997 | bool parent_is_format, |
28518102 | 3998 | QDict *parent_options, |
077e8e20 AG |
3999 | int parent_flags, |
4000 | bool keep_old_opts) | |
e971aa12 JC |
4001 | { |
4002 | assert(bs != NULL); | |
4003 | ||
4004 | BlockReopenQueueEntry *bs_entry; | |
67251a31 | 4005 | BdrvChild *child; |
9aa09ddd AG |
4006 | QDict *old_options, *explicit_options, *options_copy; |
4007 | int flags; | |
4008 | QemuOpts *opts; | |
67251a31 | 4009 | |
1a63a907 KW |
4010 | /* Make sure that the caller remembered to use a drained section. This is |
4011 | * important to avoid graph changes between the recursive queuing here and | |
4012 | * bdrv_reopen_multiple(). */ | |
4013 | assert(bs->quiesce_counter > 0); | |
4014 | ||
e971aa12 JC |
4015 | if (bs_queue == NULL) { |
4016 | bs_queue = g_new0(BlockReopenQueue, 1); | |
859443b0 | 4017 | QTAILQ_INIT(bs_queue); |
e971aa12 JC |
4018 | } |
4019 | ||
4d2cb092 KW |
4020 | if (!options) { |
4021 | options = qdict_new(); | |
4022 | } | |
4023 | ||
5b7ba05f | 4024 | /* Check if this BlockDriverState is already in the queue */ |
859443b0 | 4025 | QTAILQ_FOREACH(bs_entry, bs_queue, entry) { |
5b7ba05f AG |
4026 | if (bs == bs_entry->state.bs) { |
4027 | break; | |
4028 | } | |
4029 | } | |
4030 | ||
28518102 KW |
4031 | /* |
4032 | * Precedence of options: | |
4033 | * 1. Explicitly passed in options (highest) | |
9aa09ddd AG |
4034 | * 2. Retained from explicitly set options of bs |
4035 | * 3. Inherited from parent node | |
4036 | * 4. Retained from effective options of bs | |
28518102 KW |
4037 | */ |
4038 | ||
145f598e | 4039 | /* Old explicitly set values (don't overwrite by inherited value) */ |
077e8e20 AG |
4040 | if (bs_entry || keep_old_opts) { |
4041 | old_options = qdict_clone_shallow(bs_entry ? | |
4042 | bs_entry->state.explicit_options : | |
4043 | bs->explicit_options); | |
4044 | bdrv_join_options(bs, options, old_options); | |
4045 | qobject_unref(old_options); | |
5b7ba05f | 4046 | } |
145f598e KW |
4047 | |
4048 | explicit_options = qdict_clone_shallow(options); | |
4049 | ||
28518102 KW |
4050 | /* Inherit from parent node */ |
4051 | if (parent_options) { | |
9aa09ddd | 4052 | flags = 0; |
3cdc69d3 | 4053 | klass->inherit_options(role, parent_is_format, &flags, options, |
272c02ea | 4054 | parent_flags, parent_options); |
9aa09ddd AG |
4055 | } else { |
4056 | flags = bdrv_get_flags(bs); | |
28518102 KW |
4057 | } |
4058 | ||
077e8e20 AG |
4059 | if (keep_old_opts) { |
4060 | /* Old values are used for options that aren't set yet */ | |
4061 | old_options = qdict_clone_shallow(bs->options); | |
4062 | bdrv_join_options(bs, options, old_options); | |
4063 | qobject_unref(old_options); | |
4064 | } | |
4d2cb092 | 4065 | |
9aa09ddd AG |
4066 | /* We have the final set of options so let's update the flags */ |
4067 | options_copy = qdict_clone_shallow(options); | |
4068 | opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort); | |
4069 | qemu_opts_absorb_qdict(opts, options_copy, NULL); | |
4070 | update_flags_from_options(&flags, opts); | |
4071 | qemu_opts_del(opts); | |
4072 | qobject_unref(options_copy); | |
4073 | ||
fd452021 | 4074 | /* bdrv_open_inherit() sets and clears some additional flags internally */ |
f1f25a2e | 4075 | flags &= ~BDRV_O_PROTOCOL; |
fd452021 KW |
4076 | if (flags & BDRV_O_RDWR) { |
4077 | flags |= BDRV_O_ALLOW_RDWR; | |
4078 | } | |
f1f25a2e | 4079 | |
1857c97b KW |
4080 | if (!bs_entry) { |
4081 | bs_entry = g_new0(BlockReopenQueueEntry, 1); | |
859443b0 | 4082 | QTAILQ_INSERT_TAIL(bs_queue, bs_entry, entry); |
1857c97b | 4083 | } else { |
cb3e7f08 MAL |
4084 | qobject_unref(bs_entry->state.options); |
4085 | qobject_unref(bs_entry->state.explicit_options); | |
1857c97b KW |
4086 | } |
4087 | ||
4088 | bs_entry->state.bs = bs; | |
4089 | bs_entry->state.options = options; | |
4090 | bs_entry->state.explicit_options = explicit_options; | |
4091 | bs_entry->state.flags = flags; | |
4092 | ||
30450259 KW |
4093 | /* This needs to be overwritten in bdrv_reopen_prepare() */ |
4094 | bs_entry->state.perm = UINT64_MAX; | |
4095 | bs_entry->state.shared_perm = 0; | |
4096 | ||
8546632e AG |
4097 | /* |
4098 | * If keep_old_opts is false then it means that unspecified | |
4099 | * options must be reset to their original value. We don't allow | |
4100 | * resetting 'backing' but we need to know if the option is | |
4101 | * missing in order to decide if we have to return an error. | |
4102 | */ | |
4103 | if (!keep_old_opts) { | |
4104 | bs_entry->state.backing_missing = | |
4105 | !qdict_haskey(options, "backing") && | |
4106 | !qdict_haskey(options, "backing.driver"); | |
4107 | } | |
4108 | ||
67251a31 | 4109 | QLIST_FOREACH(child, &bs->children, next) { |
8546632e AG |
4110 | QDict *new_child_options = NULL; |
4111 | bool child_keep_old = keep_old_opts; | |
67251a31 | 4112 | |
4c9dfe5d KW |
4113 | /* reopen can only change the options of block devices that were |
4114 | * implicitly created and inherited options. For other (referenced) | |
4115 | * block devices, a syntax like "backing.foo" results in an error. */ | |
67251a31 KW |
4116 | if (child->bs->inherits_from != bs) { |
4117 | continue; | |
4118 | } | |
4119 | ||
8546632e AG |
4120 | /* Check if the options contain a child reference */ |
4121 | if (qdict_haskey(options, child->name)) { | |
4122 | const char *childref = qdict_get_try_str(options, child->name); | |
4123 | /* | |
4124 | * The current child must not be reopened if the child | |
4125 | * reference is null or points to a different node. | |
4126 | */ | |
4127 | if (g_strcmp0(childref, child->bs->node_name)) { | |
4128 | continue; | |
4129 | } | |
4130 | /* | |
4131 | * If the child reference points to the current child then | |
4132 | * reopen it with its existing set of options (note that | |
4133 | * it can still inherit new options from the parent). | |
4134 | */ | |
4135 | child_keep_old = true; | |
4136 | } else { | |
4137 | /* Extract child options ("child-name.*") */ | |
4138 | char *child_key_dot = g_strdup_printf("%s.", child->name); | |
4139 | qdict_extract_subqdict(explicit_options, NULL, child_key_dot); | |
4140 | qdict_extract_subqdict(options, &new_child_options, child_key_dot); | |
4141 | g_free(child_key_dot); | |
4142 | } | |
4c9dfe5d | 4143 | |
9aa09ddd | 4144 | bdrv_reopen_queue_child(bs_queue, child->bs, new_child_options, |
3cdc69d3 HR |
4145 | child->klass, child->role, bs->drv->is_format, |
4146 | options, flags, child_keep_old); | |
e971aa12 JC |
4147 | } |
4148 | ||
e971aa12 JC |
4149 | return bs_queue; |
4150 | } | |
4151 | ||
28518102 KW |
4152 | BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, |
4153 | BlockDriverState *bs, | |
077e8e20 | 4154 | QDict *options, bool keep_old_opts) |
28518102 | 4155 | { |
3cdc69d3 HR |
4156 | return bdrv_reopen_queue_child(bs_queue, bs, options, NULL, 0, false, |
4157 | NULL, 0, keep_old_opts); | |
28518102 KW |
4158 | } |
4159 | ||
e971aa12 JC |
4160 | /* |
4161 | * Reopen multiple BlockDriverStates atomically & transactionally. | |
4162 | * | |
4163 | * The queue passed in (bs_queue) must have been built up previous | |
4164 | * via bdrv_reopen_queue(). | |
4165 | * | |
4166 | * Reopens all BDS specified in the queue, with the appropriate | |
4167 | * flags. All devices are prepared for reopen, and failure of any | |
50d6a8a3 | 4168 | * device will cause all device changes to be abandoned, and intermediate |
e971aa12 JC |
4169 | * data cleaned up. |
4170 | * | |
4171 | * If all devices prepare successfully, then the changes are committed | |
4172 | * to all devices. | |
4173 | * | |
1a63a907 KW |
4174 | * All affected nodes must be drained between bdrv_reopen_queue() and |
4175 | * bdrv_reopen_multiple(). | |
e971aa12 | 4176 | */ |
5019aece | 4177 | int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) |
e971aa12 JC |
4178 | { |
4179 | int ret = -1; | |
4180 | BlockReopenQueueEntry *bs_entry, *next; | |
e971aa12 JC |
4181 | |
4182 | assert(bs_queue != NULL); | |
4183 | ||
859443b0 | 4184 | QTAILQ_FOREACH(bs_entry, bs_queue, entry) { |
1a63a907 | 4185 | assert(bs_entry->state.bs->quiesce_counter > 0); |
a4615ab3 | 4186 | if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, errp)) { |
e971aa12 JC |
4187 | goto cleanup; |
4188 | } | |
4189 | bs_entry->prepared = true; | |
4190 | } | |
4191 | ||
859443b0 | 4192 | QTAILQ_FOREACH(bs_entry, bs_queue, entry) { |
69b736e7 KW |
4193 | BDRVReopenState *state = &bs_entry->state; |
4194 | ret = bdrv_check_perm(state->bs, bs_queue, state->perm, | |
071b474f | 4195 | state->shared_perm, NULL, errp); |
69b736e7 KW |
4196 | if (ret < 0) { |
4197 | goto cleanup_perm; | |
4198 | } | |
cb828c31 AG |
4199 | /* Check if new_backing_bs would accept the new permissions */ |
4200 | if (state->replace_backing_bs && state->new_backing_bs) { | |
4201 | uint64_t nperm, nshared; | |
4202 | bdrv_child_perm(state->bs, state->new_backing_bs, | |
e5d8a406 | 4203 | NULL, bdrv_backing_role(state->bs), |
25191e5f | 4204 | bs_queue, state->perm, state->shared_perm, |
cb828c31 AG |
4205 | &nperm, &nshared); |
4206 | ret = bdrv_check_update_perm(state->new_backing_bs, NULL, | |
071b474f | 4207 | nperm, nshared, NULL, errp); |
cb828c31 AG |
4208 | if (ret < 0) { |
4209 | goto cleanup_perm; | |
4210 | } | |
4211 | } | |
69b736e7 KW |
4212 | bs_entry->perms_checked = true; |
4213 | } | |
4214 | ||
fcd6a4f4 VSO |
4215 | /* |
4216 | * If we reach this point, we have success and just need to apply the | |
4217 | * changes. | |
4218 | * | |
4219 | * Reverse order is used to comfort qcow2 driver: on commit it need to write | |
4220 | * IN_USE flag to the image, to mark bitmaps in the image as invalid. But | |
4221 | * children are usually goes after parents in reopen-queue, so go from last | |
4222 | * to first element. | |
e971aa12 | 4223 | */ |
fcd6a4f4 | 4224 | QTAILQ_FOREACH_REVERSE(bs_entry, bs_queue, entry) { |
e971aa12 JC |
4225 | bdrv_reopen_commit(&bs_entry->state); |
4226 | } | |
4227 | ||
4228 | ret = 0; | |
69b736e7 | 4229 | cleanup_perm: |
859443b0 | 4230 | QTAILQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) { |
69b736e7 KW |
4231 | BDRVReopenState *state = &bs_entry->state; |
4232 | ||
4233 | if (!bs_entry->perms_checked) { | |
4234 | continue; | |
4235 | } | |
e971aa12 | 4236 | |
69b736e7 | 4237 | if (ret == 0) { |
74ad9a3b VSO |
4238 | uint64_t perm, shared; |
4239 | ||
4240 | bdrv_get_cumulative_perm(state->bs, &perm, &shared); | |
4241 | assert(perm == state->perm); | |
4242 | assert(shared == state->shared_perm); | |
4243 | ||
4244 | bdrv_set_perm(state->bs); | |
69b736e7 KW |
4245 | } else { |
4246 | bdrv_abort_perm_update(state->bs); | |
cb828c31 AG |
4247 | if (state->replace_backing_bs && state->new_backing_bs) { |
4248 | bdrv_abort_perm_update(state->new_backing_bs); | |
4249 | } | |
69b736e7 KW |
4250 | } |
4251 | } | |
17e1e2be PK |
4252 | |
4253 | if (ret == 0) { | |
4254 | QTAILQ_FOREACH_REVERSE(bs_entry, bs_queue, entry) { | |
4255 | BlockDriverState *bs = bs_entry->state.bs; | |
4256 | ||
4257 | if (bs->drv->bdrv_reopen_commit_post) | |
4258 | bs->drv->bdrv_reopen_commit_post(&bs_entry->state); | |
4259 | } | |
4260 | } | |
e971aa12 | 4261 | cleanup: |
859443b0 | 4262 | QTAILQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) { |
1bab38e7 AG |
4263 | if (ret) { |
4264 | if (bs_entry->prepared) { | |
4265 | bdrv_reopen_abort(&bs_entry->state); | |
4266 | } | |
cb3e7f08 | 4267 | qobject_unref(bs_entry->state.explicit_options); |
4c8350fe | 4268 | qobject_unref(bs_entry->state.options); |
e971aa12 | 4269 | } |
cb828c31 AG |
4270 | if (bs_entry->state.new_backing_bs) { |
4271 | bdrv_unref(bs_entry->state.new_backing_bs); | |
4272 | } | |
e971aa12 JC |
4273 | g_free(bs_entry); |
4274 | } | |
4275 | g_free(bs_queue); | |
40840e41 | 4276 | |
e971aa12 JC |
4277 | return ret; |
4278 | } | |
4279 | ||
6e1000a8 AG |
4280 | int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, |
4281 | Error **errp) | |
4282 | { | |
4283 | int ret; | |
4284 | BlockReopenQueue *queue; | |
4285 | QDict *opts = qdict_new(); | |
4286 | ||
4287 | qdict_put_bool(opts, BDRV_OPT_READ_ONLY, read_only); | |
4288 | ||
4289 | bdrv_subtree_drained_begin(bs); | |
077e8e20 | 4290 | queue = bdrv_reopen_queue(NULL, bs, opts, true); |
5019aece | 4291 | ret = bdrv_reopen_multiple(queue, errp); |
6e1000a8 AG |
4292 | bdrv_subtree_drained_end(bs); |
4293 | ||
4294 | return ret; | |
4295 | } | |
4296 | ||
30450259 KW |
4297 | static BlockReopenQueueEntry *find_parent_in_reopen_queue(BlockReopenQueue *q, |
4298 | BdrvChild *c) | |
4299 | { | |
4300 | BlockReopenQueueEntry *entry; | |
4301 | ||
859443b0 | 4302 | QTAILQ_FOREACH(entry, q, entry) { |
30450259 KW |
4303 | BlockDriverState *bs = entry->state.bs; |
4304 | BdrvChild *child; | |
4305 | ||
4306 | QLIST_FOREACH(child, &bs->children, next) { | |
4307 | if (child == c) { | |
4308 | return entry; | |
4309 | } | |
4310 | } | |
4311 | } | |
4312 | ||
4313 | return NULL; | |
4314 | } | |
4315 | ||
4316 | static void bdrv_reopen_perm(BlockReopenQueue *q, BlockDriverState *bs, | |
4317 | uint64_t *perm, uint64_t *shared) | |
4318 | { | |
4319 | BdrvChild *c; | |
4320 | BlockReopenQueueEntry *parent; | |
4321 | uint64_t cumulative_perms = 0; | |
4322 | uint64_t cumulative_shared_perms = BLK_PERM_ALL; | |
4323 | ||
4324 | QLIST_FOREACH(c, &bs->parents, next_parent) { | |
4325 | parent = find_parent_in_reopen_queue(q, c); | |
4326 | if (!parent) { | |
4327 | cumulative_perms |= c->perm; | |
4328 | cumulative_shared_perms &= c->shared_perm; | |
4329 | } else { | |
4330 | uint64_t nperm, nshared; | |
4331 | ||
e5d8a406 | 4332 | bdrv_child_perm(parent->state.bs, bs, c, c->role, q, |
30450259 KW |
4333 | parent->state.perm, parent->state.shared_perm, |
4334 | &nperm, &nshared); | |
4335 | ||
4336 | cumulative_perms |= nperm; | |
4337 | cumulative_shared_perms &= nshared; | |
4338 | } | |
4339 | } | |
4340 | *perm = cumulative_perms; | |
4341 | *shared = cumulative_shared_perms; | |
4342 | } | |
e971aa12 | 4343 | |
1de6b45f KW |
4344 | static bool bdrv_reopen_can_attach(BlockDriverState *parent, |
4345 | BdrvChild *child, | |
4346 | BlockDriverState *new_child, | |
4347 | Error **errp) | |
4348 | { | |
4349 | AioContext *parent_ctx = bdrv_get_aio_context(parent); | |
4350 | AioContext *child_ctx = bdrv_get_aio_context(new_child); | |
4351 | GSList *ignore; | |
4352 | bool ret; | |
4353 | ||
4354 | ignore = g_slist_prepend(NULL, child); | |
4355 | ret = bdrv_can_set_aio_context(new_child, parent_ctx, &ignore, NULL); | |
4356 | g_slist_free(ignore); | |
4357 | if (ret) { | |
4358 | return ret; | |
4359 | } | |
4360 | ||
4361 | ignore = g_slist_prepend(NULL, child); | |
4362 | ret = bdrv_can_set_aio_context(parent, child_ctx, &ignore, errp); | |
4363 | g_slist_free(ignore); | |
4364 | return ret; | |
4365 | } | |
4366 | ||
cb828c31 AG |
4367 | /* |
4368 | * Take a BDRVReopenState and check if the value of 'backing' in the | |
4369 | * reopen_state->options QDict is valid or not. | |
4370 | * | |
4371 | * If 'backing' is missing from the QDict then return 0. | |
4372 | * | |
4373 | * If 'backing' contains the node name of the backing file of | |
4374 | * reopen_state->bs then return 0. | |
4375 | * | |
4376 | * If 'backing' contains a different node name (or is null) then check | |
4377 | * whether the current backing file can be replaced with the new one. | |
4378 | * If that's the case then reopen_state->replace_backing_bs is set to | |
4379 | * true and reopen_state->new_backing_bs contains a pointer to the new | |
4380 | * backing BlockDriverState (or NULL). | |
4381 | * | |
4382 | * Return 0 on success, otherwise return < 0 and set @errp. | |
4383 | */ | |
4384 | static int bdrv_reopen_parse_backing(BDRVReopenState *reopen_state, | |
4385 | Error **errp) | |
4386 | { | |
4387 | BlockDriverState *bs = reopen_state->bs; | |
1d42f48c | 4388 | BlockDriverState *overlay_bs, *below_bs, *new_backing_bs; |
cb828c31 AG |
4389 | QObject *value; |
4390 | const char *str; | |
4391 | ||
4392 | value = qdict_get(reopen_state->options, "backing"); | |
4393 | if (value == NULL) { | |
4394 | return 0; | |
4395 | } | |
4396 | ||
4397 | switch (qobject_type(value)) { | |
4398 | case QTYPE_QNULL: | |
4399 | new_backing_bs = NULL; | |
4400 | break; | |
4401 | case QTYPE_QSTRING: | |
410f44f5 | 4402 | str = qstring_get_str(qobject_to(QString, value)); |
cb828c31 AG |
4403 | new_backing_bs = bdrv_lookup_bs(NULL, str, errp); |
4404 | if (new_backing_bs == NULL) { | |
4405 | return -EINVAL; | |
4406 | } else if (bdrv_recurse_has_child(new_backing_bs, bs)) { | |
4407 | error_setg(errp, "Making '%s' a backing file of '%s' " | |
4408 | "would create a cycle", str, bs->node_name); | |
4409 | return -EINVAL; | |
4410 | } | |
4411 | break; | |
4412 | default: | |
4413 | /* 'backing' does not allow any other data type */ | |
4414 | g_assert_not_reached(); | |
4415 | } | |
4416 | ||
4417 | /* | |
1de6b45f KW |
4418 | * Check AioContext compatibility so that the bdrv_set_backing_hd() call in |
4419 | * bdrv_reopen_commit() won't fail. | |
cb828c31 AG |
4420 | */ |
4421 | if (new_backing_bs) { | |
1de6b45f | 4422 | if (!bdrv_reopen_can_attach(bs, bs->backing, new_backing_bs, errp)) { |
cb828c31 AG |
4423 | return -EINVAL; |
4424 | } | |
4425 | } | |
4426 | ||
1d42f48c HR |
4427 | /* |
4428 | * Ensure that @bs can really handle backing files, because we are | |
4429 | * about to give it one (or swap the existing one) | |
4430 | */ | |
4431 | if (bs->drv->is_filter) { | |
4432 | /* Filters always have a file or a backing child */ | |
4433 | if (!bs->backing) { | |
4434 | error_setg(errp, "'%s' is a %s filter node that does not support a " | |
4435 | "backing child", bs->node_name, bs->drv->format_name); | |
4436 | return -EINVAL; | |
4437 | } | |
4438 | } else if (!bs->drv->supports_backing) { | |
4439 | error_setg(errp, "Driver '%s' of node '%s' does not support backing " | |
4440 | "files", bs->drv->format_name, bs->node_name); | |
4441 | return -EINVAL; | |
4442 | } | |
4443 | ||
cb828c31 AG |
4444 | /* |
4445 | * Find the "actual" backing file by skipping all links that point | |
4446 | * to an implicit node, if any (e.g. a commit filter node). | |
1d42f48c HR |
4447 | * We cannot use any of the bdrv_skip_*() functions here because |
4448 | * those return the first explicit node, while we are looking for | |
4449 | * its overlay here. | |
cb828c31 AG |
4450 | */ |
4451 | overlay_bs = bs; | |
1d42f48c HR |
4452 | for (below_bs = bdrv_filter_or_cow_bs(overlay_bs); |
4453 | below_bs && below_bs->implicit; | |
4454 | below_bs = bdrv_filter_or_cow_bs(overlay_bs)) | |
4455 | { | |
4456 | overlay_bs = below_bs; | |
cb828c31 AG |
4457 | } |
4458 | ||
4459 | /* If we want to replace the backing file we need some extra checks */ | |
1d42f48c | 4460 | if (new_backing_bs != bdrv_filter_or_cow_bs(overlay_bs)) { |
cb828c31 AG |
4461 | /* Check for implicit nodes between bs and its backing file */ |
4462 | if (bs != overlay_bs) { | |
4463 | error_setg(errp, "Cannot change backing link if '%s' has " | |
4464 | "an implicit backing file", bs->node_name); | |
4465 | return -EPERM; | |
4466 | } | |
1d42f48c HR |
4467 | /* |
4468 | * Check if the backing link that we want to replace is frozen. | |
4469 | * Note that | |
4470 | * bdrv_filter_or_cow_child(overlay_bs) == overlay_bs->backing, | |
4471 | * because we know that overlay_bs == bs, and that @bs | |
4472 | * either is a filter that uses ->backing or a COW format BDS | |
4473 | * with bs->drv->supports_backing == true. | |
4474 | */ | |
4475 | if (bdrv_is_backing_chain_frozen(overlay_bs, | |
4476 | child_bs(overlay_bs->backing), errp)) | |
4477 | { | |
cb828c31 AG |
4478 | return -EPERM; |
4479 | } | |
4480 | reopen_state->replace_backing_bs = true; | |
4481 | if (new_backing_bs) { | |
4482 | bdrv_ref(new_backing_bs); | |
4483 | reopen_state->new_backing_bs = new_backing_bs; | |
4484 | } | |
4485 | } | |
4486 | ||
4487 | return 0; | |
4488 | } | |
4489 | ||
e971aa12 JC |
4490 | /* |
4491 | * Prepares a BlockDriverState for reopen. All changes are staged in the | |
4492 | * 'opaque' field of the BDRVReopenState, which is used and allocated by | |
4493 | * the block driver layer .bdrv_reopen_prepare() | |
4494 | * | |
4495 | * bs is the BlockDriverState to reopen | |
4496 | * flags are the new open flags | |
4497 | * queue is the reopen queue | |
4498 | * | |
4499 | * Returns 0 on success, non-zero on error. On error errp will be set | |
4500 | * as well. | |
4501 | * | |
4502 | * On failure, bdrv_reopen_abort() will be called to clean up any data. | |
4503 | * It is the responsibility of the caller to then call the abort() or | |
4504 | * commit() for any other BDS that have been left in a prepare() state | |
4505 | * | |
4506 | */ | |
53e96d1e VSO |
4507 | static int bdrv_reopen_prepare(BDRVReopenState *reopen_state, |
4508 | BlockReopenQueue *queue, Error **errp) | |
e971aa12 JC |
4509 | { |
4510 | int ret = -1; | |
e6d79c41 | 4511 | int old_flags; |
e971aa12 JC |
4512 | Error *local_err = NULL; |
4513 | BlockDriver *drv; | |
ccf9dc07 | 4514 | QemuOpts *opts; |
4c8350fe | 4515 | QDict *orig_reopen_opts; |
593b3071 | 4516 | char *discard = NULL; |
3d8ce171 | 4517 | bool read_only; |
9ad08c44 | 4518 | bool drv_prepared = false; |
e971aa12 JC |
4519 | |
4520 | assert(reopen_state != NULL); | |
4521 | assert(reopen_state->bs->drv != NULL); | |
4522 | drv = reopen_state->bs->drv; | |
4523 | ||
4c8350fe AG |
4524 | /* This function and each driver's bdrv_reopen_prepare() remove |
4525 | * entries from reopen_state->options as they are processed, so | |
4526 | * we need to make a copy of the original QDict. */ | |
4527 | orig_reopen_opts = qdict_clone_shallow(reopen_state->options); | |
4528 | ||
ccf9dc07 KW |
4529 | /* Process generic block layer options */ |
4530 | opts = qemu_opts_create(&bdrv_runtime_opts, NULL, 0, &error_abort); | |
af175e85 | 4531 | if (!qemu_opts_absorb_qdict(opts, reopen_state->options, errp)) { |
ccf9dc07 KW |
4532 | ret = -EINVAL; |
4533 | goto error; | |
4534 | } | |
4535 | ||
e6d79c41 AG |
4536 | /* This was already called in bdrv_reopen_queue_child() so the flags |
4537 | * are up-to-date. This time we simply want to remove the options from | |
4538 | * QemuOpts in order to indicate that they have been processed. */ | |
4539 | old_flags = reopen_state->flags; | |
91a097e7 | 4540 | update_flags_from_options(&reopen_state->flags, opts); |
e6d79c41 | 4541 | assert(old_flags == reopen_state->flags); |
91a097e7 | 4542 | |
415bbca8 | 4543 | discard = qemu_opt_get_del(opts, BDRV_OPT_DISCARD); |
593b3071 AG |
4544 | if (discard != NULL) { |
4545 | if (bdrv_parse_discard_flags(discard, &reopen_state->flags) != 0) { | |
4546 | error_setg(errp, "Invalid discard option"); | |
4547 | ret = -EINVAL; | |
4548 | goto error; | |
4549 | } | |
4550 | } | |
4551 | ||
543770bd AG |
4552 | reopen_state->detect_zeroes = |
4553 | bdrv_parse_detect_zeroes(opts, reopen_state->flags, &local_err); | |
4554 | if (local_err) { | |
4555 | error_propagate(errp, local_err); | |
4556 | ret = -EINVAL; | |
4557 | goto error; | |
4558 | } | |
4559 | ||
57f9db9a AG |
4560 | /* All other options (including node-name and driver) must be unchanged. |
4561 | * Put them back into the QDict, so that they are checked at the end | |
4562 | * of this function. */ | |
4563 | qemu_opts_to_qdict(opts, reopen_state->options); | |
ccf9dc07 | 4564 | |
3d8ce171 JC |
4565 | /* If we are to stay read-only, do not allow permission change |
4566 | * to r/w. Attempting to set to r/w may fail if either BDRV_O_ALLOW_RDWR is | |
4567 | * not set, or if the BDS still has copy_on_read enabled */ | |
4568 | read_only = !(reopen_state->flags & BDRV_O_RDWR); | |
54a32bfe | 4569 | ret = bdrv_can_set_read_only(reopen_state->bs, read_only, true, &local_err); |
3d8ce171 JC |
4570 | if (local_err) { |
4571 | error_propagate(errp, local_err); | |
e971aa12 JC |
4572 | goto error; |
4573 | } | |
4574 | ||
30450259 KW |
4575 | /* Calculate required permissions after reopening */ |
4576 | bdrv_reopen_perm(queue, reopen_state->bs, | |
4577 | &reopen_state->perm, &reopen_state->shared_perm); | |
e971aa12 JC |
4578 | |
4579 | ret = bdrv_flush(reopen_state->bs); | |
4580 | if (ret) { | |
455b0fde | 4581 | error_setg_errno(errp, -ret, "Error flushing drive"); |
e971aa12 JC |
4582 | goto error; |
4583 | } | |
4584 | ||
4585 | if (drv->bdrv_reopen_prepare) { | |
faf116b4 AG |
4586 | /* |
4587 | * If a driver-specific option is missing, it means that we | |
4588 | * should reset it to its default value. | |
4589 | * But not all options allow that, so we need to check it first. | |
4590 | */ | |
4591 | ret = bdrv_reset_options_allowed(reopen_state->bs, | |
4592 | reopen_state->options, errp); | |
4593 | if (ret) { | |
4594 | goto error; | |
4595 | } | |
4596 | ||
e971aa12 JC |
4597 | ret = drv->bdrv_reopen_prepare(reopen_state, queue, &local_err); |
4598 | if (ret) { | |
4599 | if (local_err != NULL) { | |
4600 | error_propagate(errp, local_err); | |
4601 | } else { | |
f30c66ba | 4602 | bdrv_refresh_filename(reopen_state->bs); |
d8b6895f LC |
4603 | error_setg(errp, "failed while preparing to reopen image '%s'", |
4604 | reopen_state->bs->filename); | |
e971aa12 JC |
4605 | } |
4606 | goto error; | |
4607 | } | |
4608 | } else { | |
4609 | /* It is currently mandatory to have a bdrv_reopen_prepare() | |
4610 | * handler for each supported drv. */ | |
81e5f78a AG |
4611 | error_setg(errp, "Block format '%s' used by node '%s' " |
4612 | "does not support reopening files", drv->format_name, | |
4613 | bdrv_get_device_or_node_name(reopen_state->bs)); | |
e971aa12 JC |
4614 | ret = -1; |
4615 | goto error; | |
4616 | } | |
4617 | ||
9ad08c44 HR |
4618 | drv_prepared = true; |
4619 | ||
bacd9b87 AG |
4620 | /* |
4621 | * We must provide the 'backing' option if the BDS has a backing | |
4622 | * file or if the image file has a backing file name as part of | |
4623 | * its metadata. Otherwise the 'backing' option can be omitted. | |
4624 | */ | |
4625 | if (drv->supports_backing && reopen_state->backing_missing && | |
1d42f48c | 4626 | (reopen_state->bs->backing || reopen_state->bs->backing_file[0])) { |
8546632e AG |
4627 | error_setg(errp, "backing is missing for '%s'", |
4628 | reopen_state->bs->node_name); | |
4629 | ret = -EINVAL; | |
4630 | goto error; | |
4631 | } | |
4632 | ||
cb828c31 AG |
4633 | /* |
4634 | * Allow changing the 'backing' option. The new value can be | |
4635 | * either a reference to an existing node (using its node name) | |
4636 | * or NULL to simply detach the current backing file. | |
4637 | */ | |
4638 | ret = bdrv_reopen_parse_backing(reopen_state, errp); | |
4639 | if (ret < 0) { | |
4640 | goto error; | |
4641 | } | |
4642 | qdict_del(reopen_state->options, "backing"); | |
4643 | ||
4d2cb092 KW |
4644 | /* Options that are not handled are only okay if they are unchanged |
4645 | * compared to the old state. It is expected that some options are only | |
4646 | * used for the initial open, but not reopen (e.g. filename) */ | |
4647 | if (qdict_size(reopen_state->options)) { | |
4648 | const QDictEntry *entry = qdict_first(reopen_state->options); | |
4649 | ||
4650 | do { | |
54fd1b0d HR |
4651 | QObject *new = entry->value; |
4652 | QObject *old = qdict_get(reopen_state->bs->options, entry->key); | |
4653 | ||
db905283 AG |
4654 | /* Allow child references (child_name=node_name) as long as they |
4655 | * point to the current child (i.e. everything stays the same). */ | |
4656 | if (qobject_type(new) == QTYPE_QSTRING) { | |
4657 | BdrvChild *child; | |
4658 | QLIST_FOREACH(child, &reopen_state->bs->children, next) { | |
4659 | if (!strcmp(child->name, entry->key)) { | |
4660 | break; | |
4661 | } | |
4662 | } | |
4663 | ||
4664 | if (child) { | |
410f44f5 MA |
4665 | if (!strcmp(child->bs->node_name, |
4666 | qstring_get_str(qobject_to(QString, new)))) { | |
db905283 AG |
4667 | continue; /* Found child with this name, skip option */ |
4668 | } | |
4669 | } | |
4670 | } | |
4671 | ||
129c7d1c | 4672 | /* |
54fd1b0d HR |
4673 | * TODO: When using -drive to specify blockdev options, all values |
4674 | * will be strings; however, when using -blockdev, blockdev-add or | |
4675 | * filenames using the json:{} pseudo-protocol, they will be | |
4676 | * correctly typed. | |
4677 | * In contrast, reopening options are (currently) always strings | |
4678 | * (because you can only specify them through qemu-io; all other | |
4679 | * callers do not specify any options). | |
4680 | * Therefore, when using anything other than -drive to create a BDS, | |
4681 | * this cannot detect non-string options as unchanged, because | |
4682 | * qobject_is_equal() always returns false for objects of different | |
4683 | * type. In the future, this should be remedied by correctly typing | |
4684 | * all options. For now, this is not too big of an issue because | |
4685 | * the user can simply omit options which cannot be changed anyway, | |
4686 | * so they will stay unchanged. | |
129c7d1c | 4687 | */ |
54fd1b0d | 4688 | if (!qobject_is_equal(new, old)) { |
4d2cb092 KW |
4689 | error_setg(errp, "Cannot change the option '%s'", entry->key); |
4690 | ret = -EINVAL; | |
4691 | goto error; | |
4692 | } | |
4693 | } while ((entry = qdict_next(reopen_state->options, entry))); | |
4694 | } | |
4695 | ||
e971aa12 JC |
4696 | ret = 0; |
4697 | ||
4c8350fe AG |
4698 | /* Restore the original reopen_state->options QDict */ |
4699 | qobject_unref(reopen_state->options); | |
4700 | reopen_state->options = qobject_ref(orig_reopen_opts); | |
4701 | ||
e971aa12 | 4702 | error: |
9ad08c44 HR |
4703 | if (ret < 0 && drv_prepared) { |
4704 | /* drv->bdrv_reopen_prepare() has succeeded, so we need to | |
4705 | * call drv->bdrv_reopen_abort() before signaling an error | |
4706 | * (bdrv_reopen_multiple() will not call bdrv_reopen_abort() | |
4707 | * when the respective bdrv_reopen_prepare() has failed) */ | |
4708 | if (drv->bdrv_reopen_abort) { | |
4709 | drv->bdrv_reopen_abort(reopen_state); | |
4710 | } | |
4711 | } | |
ccf9dc07 | 4712 | qemu_opts_del(opts); |
4c8350fe | 4713 | qobject_unref(orig_reopen_opts); |
593b3071 | 4714 | g_free(discard); |
e971aa12 JC |
4715 | return ret; |
4716 | } | |
4717 | ||
4718 | /* | |
4719 | * Takes the staged changes for the reopen from bdrv_reopen_prepare(), and | |
4720 | * makes them final by swapping the staging BlockDriverState contents into | |
4721 | * the active BlockDriverState contents. | |
4722 | */ | |
53e96d1e | 4723 | static void bdrv_reopen_commit(BDRVReopenState *reopen_state) |
e971aa12 JC |
4724 | { |
4725 | BlockDriver *drv; | |
50bf65ba | 4726 | BlockDriverState *bs; |
50196d7a | 4727 | BdrvChild *child; |
e971aa12 JC |
4728 | |
4729 | assert(reopen_state != NULL); | |
50bf65ba VSO |
4730 | bs = reopen_state->bs; |
4731 | drv = bs->drv; | |
e971aa12 JC |
4732 | assert(drv != NULL); |
4733 | ||
4734 | /* If there are any driver level actions to take */ | |
4735 | if (drv->bdrv_reopen_commit) { | |
4736 | drv->bdrv_reopen_commit(reopen_state); | |
4737 | } | |
4738 | ||
4739 | /* set BDS specific flags now */ | |
cb3e7f08 | 4740 | qobject_unref(bs->explicit_options); |
4c8350fe | 4741 | qobject_unref(bs->options); |
145f598e | 4742 | |
50bf65ba | 4743 | bs->explicit_options = reopen_state->explicit_options; |
4c8350fe | 4744 | bs->options = reopen_state->options; |
50bf65ba VSO |
4745 | bs->open_flags = reopen_state->flags; |
4746 | bs->read_only = !(reopen_state->flags & BDRV_O_RDWR); | |
543770bd | 4747 | bs->detect_zeroes = reopen_state->detect_zeroes; |
355ef4ac | 4748 | |
cb828c31 AG |
4749 | if (reopen_state->replace_backing_bs) { |
4750 | qdict_del(bs->explicit_options, "backing"); | |
4751 | qdict_del(bs->options, "backing"); | |
4752 | } | |
4753 | ||
50196d7a AG |
4754 | /* Remove child references from bs->options and bs->explicit_options. |
4755 | * Child options were already removed in bdrv_reopen_queue_child() */ | |
4756 | QLIST_FOREACH(child, &bs->children, next) { | |
4757 | qdict_del(bs->explicit_options, child->name); | |
4758 | qdict_del(bs->options, child->name); | |
4759 | } | |
4760 | ||
cb828c31 AG |
4761 | /* |
4762 | * Change the backing file if a new one was specified. We do this | |
4763 | * after updating bs->options, so bdrv_refresh_filename() (called | |
4764 | * from bdrv_set_backing_hd()) has the new values. | |
4765 | */ | |
4766 | if (reopen_state->replace_backing_bs) { | |
1d42f48c | 4767 | BlockDriverState *old_backing_bs = child_bs(bs->backing); |
cb828c31 AG |
4768 | assert(!old_backing_bs || !old_backing_bs->implicit); |
4769 | /* Abort the permission update on the backing bs we're detaching */ | |
4770 | if (old_backing_bs) { | |
4771 | bdrv_abort_perm_update(old_backing_bs); | |
4772 | } | |
4773 | bdrv_set_backing_hd(bs, reopen_state->new_backing_bs, &error_abort); | |
4774 | } | |
4775 | ||
50bf65ba | 4776 | bdrv_refresh_limits(bs, NULL); |
e971aa12 JC |
4777 | } |
4778 | ||
4779 | /* | |
4780 | * Abort the reopen, and delete and free the staged changes in | |
4781 | * reopen_state | |
4782 | */ | |
53e96d1e | 4783 | static void bdrv_reopen_abort(BDRVReopenState *reopen_state) |
e971aa12 JC |
4784 | { |
4785 | BlockDriver *drv; | |
4786 | ||
4787 | assert(reopen_state != NULL); | |
4788 | drv = reopen_state->bs->drv; | |
4789 | assert(drv != NULL); | |
4790 | ||
4791 | if (drv->bdrv_reopen_abort) { | |
4792 | drv->bdrv_reopen_abort(reopen_state); | |
4793 | } | |
4794 | } | |
4795 | ||
4796 | ||
64dff520 | 4797 | static void bdrv_close(BlockDriverState *bs) |
fc01f7e7 | 4798 | { |
33384421 | 4799 | BdrvAioNotifier *ban, *ban_next; |
50a3efb0 | 4800 | BdrvChild *child, *next; |
33384421 | 4801 | |
30f55fb8 | 4802 | assert(!bs->refcnt); |
99b7e775 | 4803 | |
fc27291d | 4804 | bdrv_drained_begin(bs); /* complete I/O */ |
58fda173 | 4805 | bdrv_flush(bs); |
53ec73e2 | 4806 | bdrv_drain(bs); /* in case flush left pending I/O */ |
fc27291d | 4807 | |
3cbc002c | 4808 | if (bs->drv) { |
3c005293 | 4809 | if (bs->drv->bdrv_close) { |
7b99a266 | 4810 | /* Must unfreeze all children, so bdrv_unref_child() works */ |
3c005293 VSO |
4811 | bs->drv->bdrv_close(bs); |
4812 | } | |
9a4f4c31 | 4813 | bs->drv = NULL; |
50a3efb0 | 4814 | } |
9a7dedbc | 4815 | |
50a3efb0 | 4816 | QLIST_FOREACH_SAFE(child, &bs->children, next, next) { |
dd4118c7 | 4817 | bdrv_unref_child(bs, child); |
b338082b | 4818 | } |
98f90dba | 4819 | |
dd4118c7 AG |
4820 | bs->backing = NULL; |
4821 | bs->file = NULL; | |
50a3efb0 AG |
4822 | g_free(bs->opaque); |
4823 | bs->opaque = NULL; | |
d73415a3 | 4824 | qatomic_set(&bs->copy_on_read, 0); |
50a3efb0 AG |
4825 | bs->backing_file[0] = '\0'; |
4826 | bs->backing_format[0] = '\0'; | |
4827 | bs->total_sectors = 0; | |
4828 | bs->encrypted = false; | |
4829 | bs->sg = false; | |
cb3e7f08 MAL |
4830 | qobject_unref(bs->options); |
4831 | qobject_unref(bs->explicit_options); | |
50a3efb0 AG |
4832 | bs->options = NULL; |
4833 | bs->explicit_options = NULL; | |
cb3e7f08 | 4834 | qobject_unref(bs->full_open_options); |
50a3efb0 AG |
4835 | bs->full_open_options = NULL; |
4836 | ||
cca43ae1 VSO |
4837 | bdrv_release_named_dirty_bitmaps(bs); |
4838 | assert(QLIST_EMPTY(&bs->dirty_bitmaps)); | |
4839 | ||
33384421 HR |
4840 | QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_next) { |
4841 | g_free(ban); | |
4842 | } | |
4843 | QLIST_INIT(&bs->aio_notifiers); | |
fc27291d | 4844 | bdrv_drained_end(bs); |
1a6d3bd2 GK |
4845 | |
4846 | /* | |
4847 | * If we're still inside some bdrv_drain_all_begin()/end() sections, end | |
4848 | * them now since this BDS won't exist anymore when bdrv_drain_all_end() | |
4849 | * gets called. | |
4850 | */ | |
4851 | if (bs->quiesce_counter) { | |
4852 | bdrv_drain_all_end_quiesce(bs); | |
4853 | } | |
b338082b FB |
4854 | } |
4855 | ||
2bc93fed MK |
4856 | void bdrv_close_all(void) |
4857 | { | |
b3b5299d | 4858 | assert(job_next(NULL) == NULL); |
ca9bd24c HR |
4859 | |
4860 | /* Drop references from requests still in flight, such as canceled block | |
4861 | * jobs whose AIO context has not been polled yet */ | |
4862 | bdrv_drain_all(); | |
2bc93fed | 4863 | |
ca9bd24c HR |
4864 | blk_remove_all_bs(); |
4865 | blockdev_close_all_bdrv_states(); | |
ed78cda3 | 4866 | |
a1a2af07 | 4867 | assert(QTAILQ_EMPTY(&all_bdrv_states)); |
2bc93fed MK |
4868 | } |
4869 | ||
d0ac0380 KW |
4870 | static bool should_update_child(BdrvChild *c, BlockDriverState *to) |
4871 | { | |
2f30b7c3 VSO |
4872 | GQueue *queue; |
4873 | GHashTable *found; | |
4874 | bool ret; | |
d0ac0380 | 4875 | |
bd86fb99 | 4876 | if (c->klass->stay_at_node) { |
d0ac0380 KW |
4877 | return false; |
4878 | } | |
4879 | ||
ec9f10fe HR |
4880 | /* If the child @c belongs to the BDS @to, replacing the current |
4881 | * c->bs by @to would mean to create a loop. | |
4882 | * | |
4883 | * Such a case occurs when appending a BDS to a backing chain. | |
4884 | * For instance, imagine the following chain: | |
4885 | * | |
4886 | * guest device -> node A -> further backing chain... | |
4887 | * | |
4888 | * Now we create a new BDS B which we want to put on top of this | |
4889 | * chain, so we first attach A as its backing node: | |
4890 | * | |
4891 | * node B | |
4892 | * | | |
4893 | * v | |
4894 | * guest device -> node A -> further backing chain... | |
4895 | * | |
4896 | * Finally we want to replace A by B. When doing that, we want to | |
4897 | * replace all pointers to A by pointers to B -- except for the | |
4898 | * pointer from B because (1) that would create a loop, and (2) | |
4899 | * that pointer should simply stay intact: | |
4900 | * | |
4901 | * guest device -> node B | |
4902 | * | | |
4903 | * v | |
4904 | * node A -> further backing chain... | |
4905 | * | |
4906 | * In general, when replacing a node A (c->bs) by a node B (@to), | |
4907 | * if A is a child of B, that means we cannot replace A by B there | |
4908 | * because that would create a loop. Silently detaching A from B | |
4909 | * is also not really an option. So overall just leaving A in | |
2f30b7c3 VSO |
4910 | * place there is the most sensible choice. |
4911 | * | |
4912 | * We would also create a loop in any cases where @c is only | |
4913 | * indirectly referenced by @to. Prevent this by returning false | |
4914 | * if @c is found (by breadth-first search) anywhere in the whole | |
4915 | * subtree of @to. | |
4916 | */ | |
4917 | ||
4918 | ret = true; | |
4919 | found = g_hash_table_new(NULL, NULL); | |
4920 | g_hash_table_add(found, to); | |
4921 | queue = g_queue_new(); | |
4922 | g_queue_push_tail(queue, to); | |
4923 | ||
4924 | while (!g_queue_is_empty(queue)) { | |
4925 | BlockDriverState *v = g_queue_pop_head(queue); | |
4926 | BdrvChild *c2; | |
4927 | ||
4928 | QLIST_FOREACH(c2, &v->children, next) { | |
4929 | if (c2 == c) { | |
4930 | ret = false; | |
4931 | break; | |
4932 | } | |
4933 | ||
4934 | if (g_hash_table_contains(found, c2->bs)) { | |
4935 | continue; | |
4936 | } | |
4937 | ||
4938 | g_queue_push_tail(queue, c2->bs); | |
4939 | g_hash_table_add(found, c2->bs); | |
d0ac0380 KW |
4940 | } |
4941 | } | |
4942 | ||
2f30b7c3 VSO |
4943 | g_queue_free(queue); |
4944 | g_hash_table_destroy(found); | |
4945 | ||
4946 | return ret; | |
d0ac0380 KW |
4947 | } |
4948 | ||
313274bb VSO |
4949 | /* |
4950 | * With auto_skip=true bdrv_replace_node_common skips updating from parents | |
4951 | * if it creates a parent-child relation loop or if parent is block-job. | |
4952 | * | |
4953 | * With auto_skip=false the error is returned if from has a parent which should | |
4954 | * not be updated. | |
4955 | */ | |
a1e708fc VSO |
4956 | static int bdrv_replace_node_common(BlockDriverState *from, |
4957 | BlockDriverState *to, | |
4958 | bool auto_skip, Error **errp) | |
dd62f1ca | 4959 | { |
d0ac0380 | 4960 | BdrvChild *c, *next; |
3bb0e298 VSO |
4961 | Transaction *tran = tran_new(); |
4962 | g_autoptr(GHashTable) found = NULL; | |
4963 | g_autoptr(GSList) refresh_list = NULL; | |
234ac1a9 KW |
4964 | int ret; |
4965 | ||
4966 | /* Make sure that @from doesn't go away until we have successfully attached | |
4967 | * all of its parents to @to. */ | |
4968 | bdrv_ref(from); | |
dd62f1ca | 4969 | |
f871abd6 | 4970 | assert(qemu_get_current_aio_context() == qemu_get_aio_context()); |
30dd65f3 | 4971 | assert(bdrv_get_aio_context(from) == bdrv_get_aio_context(to)); |
f871abd6 KW |
4972 | bdrv_drained_begin(from); |
4973 | ||
3bb0e298 VSO |
4974 | /* |
4975 | * Do the replacement without permission update. | |
4976 | * Replacement may influence the permissions, we should calculate new | |
4977 | * permissions based on new graph. If we fail, we'll roll-back the | |
4978 | * replacement. | |
4979 | */ | |
dd62f1ca | 4980 | QLIST_FOREACH_SAFE(c, &from->parents, next_parent, next) { |
ec9f10fe | 4981 | assert(c->bs == from); |
d0ac0380 | 4982 | if (!should_update_child(c, to)) { |
313274bb VSO |
4983 | if (auto_skip) { |
4984 | continue; | |
4985 | } | |
a1e708fc | 4986 | ret = -EINVAL; |
313274bb VSO |
4987 | error_setg(errp, "Should not change '%s' link to '%s'", |
4988 | c->name, from->node_name); | |
4989 | goto out; | |
26de9438 | 4990 | } |
2cad1ebe | 4991 | if (c->frozen) { |
a1e708fc | 4992 | ret = -EPERM; |
2cad1ebe AG |
4993 | error_setg(errp, "Cannot change '%s' link to '%s'", |
4994 | c->name, from->node_name); | |
4995 | goto out; | |
4996 | } | |
3bb0e298 | 4997 | bdrv_replace_child_safe(c, to, tran); |
234ac1a9 KW |
4998 | } |
4999 | ||
3bb0e298 | 5000 | found = g_hash_table_new(NULL, NULL); |
234ac1a9 | 5001 | |
3bb0e298 VSO |
5002 | refresh_list = bdrv_topological_dfs(refresh_list, found, to); |
5003 | refresh_list = bdrv_topological_dfs(refresh_list, found, from); | |
9bd910e2 | 5004 | |
3bb0e298 VSO |
5005 | ret = bdrv_list_refresh_perms(refresh_list, NULL, tran, errp); |
5006 | if (ret < 0) { | |
5007 | goto out; | |
dd62f1ca | 5008 | } |
234ac1a9 | 5009 | |
a1e708fc VSO |
5010 | ret = 0; |
5011 | ||
234ac1a9 | 5012 | out: |
3bb0e298 VSO |
5013 | tran_finalize(tran, ret); |
5014 | ||
f871abd6 | 5015 | bdrv_drained_end(from); |
234ac1a9 | 5016 | bdrv_unref(from); |
a1e708fc VSO |
5017 | |
5018 | return ret; | |
dd62f1ca KW |
5019 | } |
5020 | ||
a1e708fc VSO |
5021 | int bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, |
5022 | Error **errp) | |
313274bb VSO |
5023 | { |
5024 | return bdrv_replace_node_common(from, to, true, errp); | |
5025 | } | |
5026 | ||
4ddc07ca PB |
5027 | /* |
5028 | * Add new bs contents at the top of an image chain while the chain is | |
5029 | * live, while keeping required fields on the top layer. | |
5030 | * | |
5031 | * This will modify the BlockDriverState fields, and swap contents | |
5032 | * between bs_new and bs_top. Both bs_new and bs_top are modified. | |
5033 | * | |
bfb197e0 | 5034 | * bs_new must not be attached to a BlockBackend. |
4ddc07ca PB |
5035 | * |
5036 | * This function does not create any image files. | |
5037 | */ | |
a1e708fc VSO |
5038 | int bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, |
5039 | Error **errp) | |
4ddc07ca | 5040 | { |
a1e708fc VSO |
5041 | int ret = bdrv_set_backing_hd(bs_new, bs_top, errp); |
5042 | if (ret < 0) { | |
ae9d4417 | 5043 | return ret; |
b2c2832c | 5044 | } |
dd62f1ca | 5045 | |
a1e708fc VSO |
5046 | ret = bdrv_replace_node(bs_top, bs_new, errp); |
5047 | if (ret < 0) { | |
234ac1a9 | 5048 | bdrv_set_backing_hd(bs_new, NULL, &error_abort); |
ae9d4417 | 5049 | return ret; |
234ac1a9 | 5050 | } |
4ddc07ca | 5051 | |
ae9d4417 | 5052 | return 0; |
8802d1fd JC |
5053 | } |
5054 | ||
4f6fd349 | 5055 | static void bdrv_delete(BlockDriverState *bs) |
b338082b | 5056 | { |
3718d8ab | 5057 | assert(bdrv_op_blocker_is_empty(bs)); |
4f6fd349 | 5058 | assert(!bs->refcnt); |
18846dee | 5059 | |
1b7bdbc1 | 5060 | /* remove from list, if necessary */ |
63eaaae0 KW |
5061 | if (bs->node_name[0] != '\0') { |
5062 | QTAILQ_REMOVE(&graph_bdrv_states, bs, node_list); | |
5063 | } | |
2c1d04e0 HR |
5064 | QTAILQ_REMOVE(&all_bdrv_states, bs, bs_list); |
5065 | ||
30c321f9 AK |
5066 | bdrv_close(bs); |
5067 | ||
7267c094 | 5068 | g_free(bs); |
fc01f7e7 FB |
5069 | } |
5070 | ||
8872ef78 AS |
5071 | BlockDriverState *bdrv_insert_node(BlockDriverState *bs, QDict *node_options, |
5072 | int flags, Error **errp) | |
5073 | { | |
5074 | BlockDriverState *new_node_bs; | |
5075 | Error *local_err = NULL; | |
5076 | ||
5077 | new_node_bs = bdrv_open(NULL, NULL, node_options, flags, errp); | |
5078 | if (new_node_bs == NULL) { | |
5079 | error_prepend(errp, "Could not create node: "); | |
5080 | return NULL; | |
5081 | } | |
5082 | ||
5083 | bdrv_drained_begin(bs); | |
5084 | bdrv_replace_node(bs, new_node_bs, &local_err); | |
5085 | bdrv_drained_end(bs); | |
5086 | ||
5087 | if (local_err) { | |
5088 | bdrv_unref(new_node_bs); | |
5089 | error_propagate(errp, local_err); | |
5090 | return NULL; | |
5091 | } | |
5092 | ||
5093 | return new_node_bs; | |
5094 | } | |
5095 | ||
e97fc193 AL |
5096 | /* |
5097 | * Run consistency checks on an image | |
5098 | * | |
e076f338 | 5099 | * Returns 0 if the check could be completed (it doesn't mean that the image is |
a1c7273b | 5100 | * free of errors) or -errno when an internal error occurred. The results of the |
e076f338 | 5101 | * check are stored in res. |
e97fc193 | 5102 | */ |
21c2283e VSO |
5103 | int coroutine_fn bdrv_co_check(BlockDriverState *bs, |
5104 | BdrvCheckResult *res, BdrvCheckMode fix) | |
e97fc193 | 5105 | { |
908bcd54 HR |
5106 | if (bs->drv == NULL) { |
5107 | return -ENOMEDIUM; | |
5108 | } | |
2fd61638 | 5109 | if (bs->drv->bdrv_co_check == NULL) { |
e97fc193 AL |
5110 | return -ENOTSUP; |
5111 | } | |
5112 | ||
e076f338 | 5113 | memset(res, 0, sizeof(*res)); |
2fd61638 PB |
5114 | return bs->drv->bdrv_co_check(bs, res, fix); |
5115 | } | |
5116 | ||
756e6736 KW |
5117 | /* |
5118 | * Return values: | |
5119 | * 0 - success | |
5120 | * -EINVAL - backing format specified, but no file | |
5121 | * -ENOSPC - can't update the backing file because no space is left in the | |
5122 | * image file header | |
5123 | * -ENOTSUP - format driver doesn't support changing the backing file | |
5124 | */ | |
e54ee1b3 EB |
5125 | int bdrv_change_backing_file(BlockDriverState *bs, const char *backing_file, |
5126 | const char *backing_fmt, bool warn) | |
756e6736 KW |
5127 | { |
5128 | BlockDriver *drv = bs->drv; | |
469ef350 | 5129 | int ret; |
756e6736 | 5130 | |
d470ad42 HR |
5131 | if (!drv) { |
5132 | return -ENOMEDIUM; | |
5133 | } | |
5134 | ||
5f377794 PB |
5135 | /* Backing file format doesn't make sense without a backing file */ |
5136 | if (backing_fmt && !backing_file) { | |
5137 | return -EINVAL; | |
5138 | } | |
5139 | ||
e54ee1b3 EB |
5140 | if (warn && backing_file && !backing_fmt) { |
5141 | warn_report("Deprecated use of backing file without explicit " | |
5142 | "backing format, use of this image requires " | |
5143 | "potentially unsafe format probing"); | |
5144 | } | |
5145 | ||
756e6736 | 5146 | if (drv->bdrv_change_backing_file != NULL) { |
469ef350 | 5147 | ret = drv->bdrv_change_backing_file(bs, backing_file, backing_fmt); |
756e6736 | 5148 | } else { |
469ef350 | 5149 | ret = -ENOTSUP; |
756e6736 | 5150 | } |
469ef350 PB |
5151 | |
5152 | if (ret == 0) { | |
5153 | pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: ""); | |
5154 | pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: ""); | |
998c2019 HR |
5155 | pstrcpy(bs->auto_backing_file, sizeof(bs->auto_backing_file), |
5156 | backing_file ?: ""); | |
469ef350 PB |
5157 | } |
5158 | return ret; | |
756e6736 KW |
5159 | } |
5160 | ||
6ebdcee2 | 5161 | /* |
dcf3f9b2 HR |
5162 | * Finds the first non-filter node above bs in the chain between |
5163 | * active and bs. The returned node is either an immediate parent of | |
5164 | * bs, or there are only filter nodes between the two. | |
6ebdcee2 JC |
5165 | * |
5166 | * Returns NULL if bs is not found in active's image chain, | |
5167 | * or if active == bs. | |
4caf0fcd JC |
5168 | * |
5169 | * Returns the bottommost base image if bs == NULL. | |
6ebdcee2 JC |
5170 | */ |
5171 | BlockDriverState *bdrv_find_overlay(BlockDriverState *active, | |
5172 | BlockDriverState *bs) | |
5173 | { | |
dcf3f9b2 HR |
5174 | bs = bdrv_skip_filters(bs); |
5175 | active = bdrv_skip_filters(active); | |
5176 | ||
5177 | while (active) { | |
5178 | BlockDriverState *next = bdrv_backing_chain_next(active); | |
5179 | if (bs == next) { | |
5180 | return active; | |
5181 | } | |
5182 | active = next; | |
6ebdcee2 JC |
5183 | } |
5184 | ||
dcf3f9b2 | 5185 | return NULL; |
4caf0fcd | 5186 | } |
6ebdcee2 | 5187 | |
4caf0fcd JC |
5188 | /* Given a BDS, searches for the base layer. */ |
5189 | BlockDriverState *bdrv_find_base(BlockDriverState *bs) | |
5190 | { | |
5191 | return bdrv_find_overlay(bs, NULL); | |
6ebdcee2 JC |
5192 | } |
5193 | ||
2cad1ebe | 5194 | /* |
7b99a266 HR |
5195 | * Return true if at least one of the COW (backing) and filter links |
5196 | * between @bs and @base is frozen. @errp is set if that's the case. | |
0f0998f6 | 5197 | * @base must be reachable from @bs, or NULL. |
2cad1ebe AG |
5198 | */ |
5199 | bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base, | |
5200 | Error **errp) | |
5201 | { | |
5202 | BlockDriverState *i; | |
7b99a266 | 5203 | BdrvChild *child; |
2cad1ebe | 5204 | |
7b99a266 HR |
5205 | for (i = bs; i != base; i = child_bs(child)) { |
5206 | child = bdrv_filter_or_cow_child(i); | |
5207 | ||
5208 | if (child && child->frozen) { | |
2cad1ebe | 5209 | error_setg(errp, "Cannot change '%s' link from '%s' to '%s'", |
7b99a266 | 5210 | child->name, i->node_name, child->bs->node_name); |
2cad1ebe AG |
5211 | return true; |
5212 | } | |
5213 | } | |
5214 | ||
5215 | return false; | |
5216 | } | |
5217 | ||
5218 | /* | |
7b99a266 | 5219 | * Freeze all COW (backing) and filter links between @bs and @base. |
2cad1ebe AG |
5220 | * If any of the links is already frozen the operation is aborted and |
5221 | * none of the links are modified. | |
0f0998f6 | 5222 | * @base must be reachable from @bs, or NULL. |
2cad1ebe AG |
5223 | * Returns 0 on success. On failure returns < 0 and sets @errp. |
5224 | */ | |
5225 | int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base, | |
5226 | Error **errp) | |
5227 | { | |
5228 | BlockDriverState *i; | |
7b99a266 | 5229 | BdrvChild *child; |
2cad1ebe AG |
5230 | |
5231 | if (bdrv_is_backing_chain_frozen(bs, base, errp)) { | |
5232 | return -EPERM; | |
5233 | } | |
5234 | ||
7b99a266 HR |
5235 | for (i = bs; i != base; i = child_bs(child)) { |
5236 | child = bdrv_filter_or_cow_child(i); | |
5237 | if (child && child->bs->never_freeze) { | |
e5182c1c | 5238 | error_setg(errp, "Cannot freeze '%s' link to '%s'", |
7b99a266 | 5239 | child->name, child->bs->node_name); |
e5182c1c HR |
5240 | return -EPERM; |
5241 | } | |
5242 | } | |
5243 | ||
7b99a266 HR |
5244 | for (i = bs; i != base; i = child_bs(child)) { |
5245 | child = bdrv_filter_or_cow_child(i); | |
5246 | if (child) { | |
5247 | child->frozen = true; | |
0f0998f6 | 5248 | } |
2cad1ebe AG |
5249 | } |
5250 | ||
5251 | return 0; | |
5252 | } | |
5253 | ||
5254 | /* | |
7b99a266 HR |
5255 | * Unfreeze all COW (backing) and filter links between @bs and @base. |
5256 | * The caller must ensure that all links are frozen before using this | |
5257 | * function. | |
0f0998f6 | 5258 | * @base must be reachable from @bs, or NULL. |
2cad1ebe AG |
5259 | */ |
5260 | void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base) | |
5261 | { | |
5262 | BlockDriverState *i; | |
7b99a266 | 5263 | BdrvChild *child; |
2cad1ebe | 5264 | |
7b99a266 HR |
5265 | for (i = bs; i != base; i = child_bs(child)) { |
5266 | child = bdrv_filter_or_cow_child(i); | |
5267 | if (child) { | |
5268 | assert(child->frozen); | |
5269 | child->frozen = false; | |
0f0998f6 | 5270 | } |
2cad1ebe AG |
5271 | } |
5272 | } | |
5273 | ||
6ebdcee2 JC |
5274 | /* |
5275 | * Drops images above 'base' up to and including 'top', and sets the image | |
5276 | * above 'top' to have base as its backing file. | |
5277 | * | |
5278 | * Requires that the overlay to 'top' is opened r/w, so that the backing file | |
5279 | * information in 'bs' can be properly updated. | |
5280 | * | |
5281 | * E.g., this will convert the following chain: | |
5282 | * bottom <- base <- intermediate <- top <- active | |
5283 | * | |
5284 | * to | |
5285 | * | |
5286 | * bottom <- base <- active | |
5287 | * | |
5288 | * It is allowed for bottom==base, in which case it converts: | |
5289 | * | |
5290 | * base <- intermediate <- top <- active | |
5291 | * | |
5292 | * to | |
5293 | * | |
5294 | * base <- active | |
5295 | * | |
54e26900 JC |
5296 | * If backing_file_str is non-NULL, it will be used when modifying top's |
5297 | * overlay image metadata. | |
5298 | * | |
6ebdcee2 JC |
5299 | * Error conditions: |
5300 | * if active == top, that is considered an error | |
5301 | * | |
5302 | */ | |
bde70715 KW |
5303 | int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, |
5304 | const char *backing_file_str) | |
6ebdcee2 | 5305 | { |
6bd858b3 AG |
5306 | BlockDriverState *explicit_top = top; |
5307 | bool update_inherits_from; | |
d669ed6a | 5308 | BdrvChild *c; |
12fa4af6 | 5309 | Error *local_err = NULL; |
6ebdcee2 | 5310 | int ret = -EIO; |
d669ed6a VSO |
5311 | g_autoptr(GSList) updated_children = NULL; |
5312 | GSList *p; | |
6ebdcee2 | 5313 | |
6858eba0 | 5314 | bdrv_ref(top); |
637d54a5 | 5315 | bdrv_subtree_drained_begin(top); |
6858eba0 | 5316 | |
6ebdcee2 JC |
5317 | if (!top->drv || !base->drv) { |
5318 | goto exit; | |
5319 | } | |
5320 | ||
5db15a57 KW |
5321 | /* Make sure that base is in the backing chain of top */ |
5322 | if (!bdrv_chain_contains(top, base)) { | |
6ebdcee2 JC |
5323 | goto exit; |
5324 | } | |
5325 | ||
6bd858b3 AG |
5326 | /* If 'base' recursively inherits from 'top' then we should set |
5327 | * base->inherits_from to top->inherits_from after 'top' and all | |
5328 | * other intermediate nodes have been dropped. | |
5329 | * If 'top' is an implicit node (e.g. "commit_top") we should skip | |
5330 | * it because no one inherits from it. We use explicit_top for that. */ | |
dcf3f9b2 | 5331 | explicit_top = bdrv_skip_implicit_filters(explicit_top); |
6bd858b3 AG |
5332 | update_inherits_from = bdrv_inherits_from_recursive(base, explicit_top); |
5333 | ||
6ebdcee2 | 5334 | /* success - we can delete the intermediate states, and link top->base */ |
bde70715 KW |
5335 | /* TODO Check graph modification op blockers (BLK_PERM_GRAPH_MOD) once |
5336 | * we've figured out how they should work. */ | |
f30c66ba HR |
5337 | if (!backing_file_str) { |
5338 | bdrv_refresh_filename(base); | |
5339 | backing_file_str = base->filename; | |
5340 | } | |
61f09cea | 5341 | |
d669ed6a VSO |
5342 | QLIST_FOREACH(c, &top->parents, next_parent) { |
5343 | updated_children = g_slist_prepend(updated_children, c); | |
5344 | } | |
5345 | ||
5346 | bdrv_replace_node_common(top, base, false, &local_err); | |
5347 | if (local_err) { | |
5348 | error_report_err(local_err); | |
5349 | goto exit; | |
5350 | } | |
5351 | ||
5352 | for (p = updated_children; p; p = p->next) { | |
5353 | c = p->data; | |
12fa4af6 | 5354 | |
bd86fb99 HR |
5355 | if (c->klass->update_filename) { |
5356 | ret = c->klass->update_filename(c, base, backing_file_str, | |
5357 | &local_err); | |
61f09cea | 5358 | if (ret < 0) { |
d669ed6a VSO |
5359 | /* |
5360 | * TODO: Actually, we want to rollback all previous iterations | |
5361 | * of this loop, and (which is almost impossible) previous | |
5362 | * bdrv_replace_node()... | |
5363 | * | |
5364 | * Note, that c->klass->update_filename may lead to permission | |
5365 | * update, so it's a bad idea to call it inside permission | |
5366 | * update transaction of bdrv_replace_node. | |
5367 | */ | |
61f09cea KW |
5368 | error_report_err(local_err); |
5369 | goto exit; | |
5370 | } | |
5371 | } | |
12fa4af6 | 5372 | } |
6ebdcee2 | 5373 | |
6bd858b3 AG |
5374 | if (update_inherits_from) { |
5375 | base->inherits_from = explicit_top->inherits_from; | |
5376 | } | |
5377 | ||
6ebdcee2 | 5378 | ret = 0; |
6ebdcee2 | 5379 | exit: |
637d54a5 | 5380 | bdrv_subtree_drained_end(top); |
6858eba0 | 5381 | bdrv_unref(top); |
6ebdcee2 JC |
5382 | return ret; |
5383 | } | |
5384 | ||
081e4650 HR |
5385 | /** |
5386 | * Implementation of BlockDriver.bdrv_get_allocated_file_size() that | |
5387 | * sums the size of all data-bearing children. (This excludes backing | |
5388 | * children.) | |
5389 | */ | |
5390 | static int64_t bdrv_sum_allocated_file_size(BlockDriverState *bs) | |
5391 | { | |
5392 | BdrvChild *child; | |
5393 | int64_t child_size, sum = 0; | |
5394 | ||
5395 | QLIST_FOREACH(child, &bs->children, next) { | |
5396 | if (child->role & (BDRV_CHILD_DATA | BDRV_CHILD_METADATA | | |
5397 | BDRV_CHILD_FILTERED)) | |
5398 | { | |
5399 | child_size = bdrv_get_allocated_file_size(child->bs); | |
5400 | if (child_size < 0) { | |
5401 | return child_size; | |
5402 | } | |
5403 | sum += child_size; | |
5404 | } | |
5405 | } | |
5406 | ||
5407 | return sum; | |
5408 | } | |
5409 | ||
61007b31 SH |
5410 | /** |
5411 | * Length of a allocated file in bytes. Sparse files are counted by actual | |
5412 | * allocated space. Return < 0 if error or unknown. | |
5413 | */ | |
5414 | int64_t bdrv_get_allocated_file_size(BlockDriverState *bs) | |
71d0770c | 5415 | { |
61007b31 SH |
5416 | BlockDriver *drv = bs->drv; |
5417 | if (!drv) { | |
5418 | return -ENOMEDIUM; | |
8f4754ed | 5419 | } |
61007b31 SH |
5420 | if (drv->bdrv_get_allocated_file_size) { |
5421 | return drv->bdrv_get_allocated_file_size(bs); | |
5422 | } | |
081e4650 HR |
5423 | |
5424 | if (drv->bdrv_file_open) { | |
5425 | /* | |
5426 | * Protocol drivers default to -ENOTSUP (most of their data is | |
5427 | * not stored in any of their children (if they even have any), | |
5428 | * so there is no generic way to figure it out). | |
5429 | */ | |
5430 | return -ENOTSUP; | |
5431 | } else if (drv->is_filter) { | |
5432 | /* Filter drivers default to the size of their filtered child */ | |
5433 | return bdrv_get_allocated_file_size(bdrv_filter_bs(bs)); | |
5434 | } else { | |
5435 | /* Other drivers default to summing their children's sizes */ | |
5436 | return bdrv_sum_allocated_file_size(bs); | |
1c9805a3 SH |
5437 | } |
5438 | } | |
e7a8a783 | 5439 | |
90880ff1 SH |
5440 | /* |
5441 | * bdrv_measure: | |
5442 | * @drv: Format driver | |
5443 | * @opts: Creation options for new image | |
5444 | * @in_bs: Existing image containing data for new image (may be NULL) | |
5445 | * @errp: Error object | |
5446 | * Returns: A #BlockMeasureInfo (free using qapi_free_BlockMeasureInfo()) | |
5447 | * or NULL on error | |
5448 | * | |
5449 | * Calculate file size required to create a new image. | |
5450 | * | |
5451 | * If @in_bs is given then space for allocated clusters and zero clusters | |
5452 | * from that image are included in the calculation. If @opts contains a | |
5453 | * backing file that is shared by @in_bs then backing clusters may be omitted | |
5454 | * from the calculation. | |
5455 | * | |
5456 | * If @in_bs is NULL then the calculation includes no allocated clusters | |
5457 | * unless a preallocation option is given in @opts. | |
5458 | * | |
5459 | * Note that @in_bs may use a different BlockDriver from @drv. | |
5460 | * | |
5461 | * If an error occurs the @errp pointer is set. | |
5462 | */ | |
5463 | BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, | |
5464 | BlockDriverState *in_bs, Error **errp) | |
5465 | { | |
5466 | if (!drv->bdrv_measure) { | |
5467 | error_setg(errp, "Block driver '%s' does not support size measurement", | |
5468 | drv->format_name); | |
5469 | return NULL; | |
5470 | } | |
5471 | ||
5472 | return drv->bdrv_measure(opts, in_bs, errp); | |
5473 | } | |
5474 | ||
61007b31 SH |
5475 | /** |
5476 | * Return number of sectors on success, -errno on error. | |
1c9805a3 | 5477 | */ |
61007b31 | 5478 | int64_t bdrv_nb_sectors(BlockDriverState *bs) |
1c9805a3 | 5479 | { |
61007b31 | 5480 | BlockDriver *drv = bs->drv; |
498e386c | 5481 | |
61007b31 SH |
5482 | if (!drv) |
5483 | return -ENOMEDIUM; | |
2572b37a | 5484 | |
61007b31 SH |
5485 | if (drv->has_variable_length) { |
5486 | int ret = refresh_total_sectors(bs, bs->total_sectors); | |
5487 | if (ret < 0) { | |
5488 | return ret; | |
1c9805a3 SH |
5489 | } |
5490 | } | |
61007b31 | 5491 | return bs->total_sectors; |
1c9805a3 | 5492 | } |
b338082b | 5493 | |
61007b31 SH |
5494 | /** |
5495 | * Return length in bytes on success, -errno on error. | |
5496 | * The length is always a multiple of BDRV_SECTOR_SIZE. | |
8d3b1a2d | 5497 | */ |
61007b31 | 5498 | int64_t bdrv_getlength(BlockDriverState *bs) |
8d3b1a2d | 5499 | { |
61007b31 | 5500 | int64_t ret = bdrv_nb_sectors(bs); |
8d3b1a2d | 5501 | |
122860ba EB |
5502 | if (ret < 0) { |
5503 | return ret; | |
5504 | } | |
5505 | if (ret > INT64_MAX / BDRV_SECTOR_SIZE) { | |
5506 | return -EFBIG; | |
5507 | } | |
5508 | return ret * BDRV_SECTOR_SIZE; | |
fc01f7e7 FB |
5509 | } |
5510 | ||
61007b31 SH |
5511 | /* return 0 as number of sectors if no device present or error */ |
5512 | void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr) | |
07d27a44 | 5513 | { |
61007b31 | 5514 | int64_t nb_sectors = bdrv_nb_sectors(bs); |
07d27a44 | 5515 | |
61007b31 | 5516 | *nb_sectors_ptr = nb_sectors < 0 ? 0 : nb_sectors; |
07d27a44 MA |
5517 | } |
5518 | ||
54115412 | 5519 | bool bdrv_is_sg(BlockDriverState *bs) |
f08145fe | 5520 | { |
61007b31 | 5521 | return bs->sg; |
f08145fe KW |
5522 | } |
5523 | ||
ae23f786 HR |
5524 | /** |
5525 | * Return whether the given node supports compressed writes. | |
5526 | */ | |
5527 | bool bdrv_supports_compressed_writes(BlockDriverState *bs) | |
5528 | { | |
5529 | BlockDriverState *filtered; | |
5530 | ||
5531 | if (!bs->drv || !block_driver_can_compress(bs->drv)) { | |
5532 | return false; | |
5533 | } | |
5534 | ||
5535 | filtered = bdrv_filter_bs(bs); | |
5536 | if (filtered) { | |
5537 | /* | |
5538 | * Filters can only forward compressed writes, so we have to | |
5539 | * check the child. | |
5540 | */ | |
5541 | return bdrv_supports_compressed_writes(filtered); | |
5542 | } | |
5543 | ||
5544 | return true; | |
5545 | } | |
5546 | ||
61007b31 | 5547 | const char *bdrv_get_format_name(BlockDriverState *bs) |
40b4f539 | 5548 | { |
61007b31 | 5549 | return bs->drv ? bs->drv->format_name : NULL; |
40b4f539 KW |
5550 | } |
5551 | ||
61007b31 | 5552 | static int qsort_strcmp(const void *a, const void *b) |
40b4f539 | 5553 | { |
ceff5bd7 | 5554 | return strcmp(*(char *const *)a, *(char *const *)b); |
40b4f539 KW |
5555 | } |
5556 | ||
61007b31 | 5557 | void bdrv_iterate_format(void (*it)(void *opaque, const char *name), |
9ac404c5 | 5558 | void *opaque, bool read_only) |
40b4f539 | 5559 | { |
61007b31 SH |
5560 | BlockDriver *drv; |
5561 | int count = 0; | |
5562 | int i; | |
5563 | const char **formats = NULL; | |
40b4f539 | 5564 | |
61007b31 SH |
5565 | QLIST_FOREACH(drv, &bdrv_drivers, list) { |
5566 | if (drv->format_name) { | |
5567 | bool found = false; | |
5568 | int i = count; | |
9ac404c5 AS |
5569 | |
5570 | if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, read_only)) { | |
5571 | continue; | |
5572 | } | |
5573 | ||
61007b31 SH |
5574 | while (formats && i && !found) { |
5575 | found = !strcmp(formats[--i], drv->format_name); | |
5576 | } | |
e2a305fb | 5577 | |
61007b31 SH |
5578 | if (!found) { |
5579 | formats = g_renew(const char *, formats, count + 1); | |
5580 | formats[count++] = drv->format_name; | |
5581 | } | |
6c5a42ac | 5582 | } |
61007b31 | 5583 | } |
6c5a42ac | 5584 | |
eb0df69f HR |
5585 | for (i = 0; i < (int)ARRAY_SIZE(block_driver_modules); i++) { |
5586 | const char *format_name = block_driver_modules[i].format_name; | |
5587 | ||
5588 | if (format_name) { | |
5589 | bool found = false; | |
5590 | int j = count; | |
5591 | ||
9ac404c5 AS |
5592 | if (use_bdrv_whitelist && |
5593 | !bdrv_format_is_whitelisted(format_name, read_only)) { | |
5594 | continue; | |
5595 | } | |
5596 | ||
eb0df69f HR |
5597 | while (formats && j && !found) { |
5598 | found = !strcmp(formats[--j], format_name); | |
5599 | } | |
5600 | ||
5601 | if (!found) { | |
5602 | formats = g_renew(const char *, formats, count + 1); | |
5603 | formats[count++] = format_name; | |
5604 | } | |
5605 | } | |
5606 | } | |
5607 | ||
61007b31 | 5608 | qsort(formats, count, sizeof(formats[0]), qsort_strcmp); |
40b4f539 | 5609 | |
61007b31 SH |
5610 | for (i = 0; i < count; i++) { |
5611 | it(opaque, formats[i]); | |
5612 | } | |
40b4f539 | 5613 | |
61007b31 SH |
5614 | g_free(formats); |
5615 | } | |
40b4f539 | 5616 | |
61007b31 SH |
5617 | /* This function is to find a node in the bs graph */ |
5618 | BlockDriverState *bdrv_find_node(const char *node_name) | |
5619 | { | |
5620 | BlockDriverState *bs; | |
391827eb | 5621 | |
61007b31 | 5622 | assert(node_name); |
40b4f539 | 5623 | |
61007b31 SH |
5624 | QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) { |
5625 | if (!strcmp(node_name, bs->node_name)) { | |
5626 | return bs; | |
40b4f539 KW |
5627 | } |
5628 | } | |
61007b31 | 5629 | return NULL; |
40b4f539 KW |
5630 | } |
5631 | ||
61007b31 | 5632 | /* Put this QMP function here so it can access the static graph_bdrv_states. */ |
facda544 PK |
5633 | BlockDeviceInfoList *bdrv_named_nodes_list(bool flat, |
5634 | Error **errp) | |
40b4f539 | 5635 | { |
9812e712 | 5636 | BlockDeviceInfoList *list; |
61007b31 | 5637 | BlockDriverState *bs; |
40b4f539 | 5638 | |
61007b31 SH |
5639 | list = NULL; |
5640 | QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) { | |
facda544 | 5641 | BlockDeviceInfo *info = bdrv_block_device_info(NULL, bs, flat, errp); |
61007b31 SH |
5642 | if (!info) { |
5643 | qapi_free_BlockDeviceInfoList(list); | |
5644 | return NULL; | |
301db7c2 | 5645 | } |
9812e712 | 5646 | QAPI_LIST_PREPEND(list, info); |
301db7c2 RH |
5647 | } |
5648 | ||
61007b31 SH |
5649 | return list; |
5650 | } | |
40b4f539 | 5651 | |
5d3b4e99 VSO |
5652 | typedef struct XDbgBlockGraphConstructor { |
5653 | XDbgBlockGraph *graph; | |
5654 | GHashTable *graph_nodes; | |
5655 | } XDbgBlockGraphConstructor; | |
5656 | ||
5657 | static XDbgBlockGraphConstructor *xdbg_graph_new(void) | |
5658 | { | |
5659 | XDbgBlockGraphConstructor *gr = g_new(XDbgBlockGraphConstructor, 1); | |
5660 | ||
5661 | gr->graph = g_new0(XDbgBlockGraph, 1); | |
5662 | gr->graph_nodes = g_hash_table_new(NULL, NULL); | |
5663 | ||
5664 | return gr; | |
5665 | } | |
5666 | ||
5667 | static XDbgBlockGraph *xdbg_graph_finalize(XDbgBlockGraphConstructor *gr) | |
5668 | { | |
5669 | XDbgBlockGraph *graph = gr->graph; | |
5670 | ||
5671 | g_hash_table_destroy(gr->graph_nodes); | |
5672 | g_free(gr); | |
5673 | ||
5674 | return graph; | |
5675 | } | |
5676 | ||
5677 | static uintptr_t xdbg_graph_node_num(XDbgBlockGraphConstructor *gr, void *node) | |
5678 | { | |
5679 | uintptr_t ret = (uintptr_t)g_hash_table_lookup(gr->graph_nodes, node); | |
5680 | ||
5681 | if (ret != 0) { | |
5682 | return ret; | |
5683 | } | |
5684 | ||
5685 | /* | |
5686 | * Start counting from 1, not 0, because 0 interferes with not-found (NULL) | |
5687 | * answer of g_hash_table_lookup. | |
5688 | */ | |
5689 | ret = g_hash_table_size(gr->graph_nodes) + 1; | |
5690 | g_hash_table_insert(gr->graph_nodes, node, (void *)ret); | |
5691 | ||
5692 | return ret; | |
5693 | } | |
5694 | ||
5695 | static void xdbg_graph_add_node(XDbgBlockGraphConstructor *gr, void *node, | |
5696 | XDbgBlockGraphNodeType type, const char *name) | |
5697 | { | |
5698 | XDbgBlockGraphNode *n; | |
5699 | ||
5700 | n = g_new0(XDbgBlockGraphNode, 1); | |
5701 | ||
5702 | n->id = xdbg_graph_node_num(gr, node); | |
5703 | n->type = type; | |
5704 | n->name = g_strdup(name); | |
5705 | ||
9812e712 | 5706 | QAPI_LIST_PREPEND(gr->graph->nodes, n); |
5d3b4e99 VSO |
5707 | } |
5708 | ||
5709 | static void xdbg_graph_add_edge(XDbgBlockGraphConstructor *gr, void *parent, | |
5710 | const BdrvChild *child) | |
5711 | { | |
cdb1cec8 | 5712 | BlockPermission qapi_perm; |
5d3b4e99 VSO |
5713 | XDbgBlockGraphEdge *edge; |
5714 | ||
5d3b4e99 VSO |
5715 | edge = g_new0(XDbgBlockGraphEdge, 1); |
5716 | ||
5717 | edge->parent = xdbg_graph_node_num(gr, parent); | |
5718 | edge->child = xdbg_graph_node_num(gr, child->bs); | |
5719 | edge->name = g_strdup(child->name); | |
5720 | ||
cdb1cec8 HR |
5721 | for (qapi_perm = 0; qapi_perm < BLOCK_PERMISSION__MAX; qapi_perm++) { |
5722 | uint64_t flag = bdrv_qapi_perm_to_blk_perm(qapi_perm); | |
5723 | ||
5724 | if (flag & child->perm) { | |
9812e712 | 5725 | QAPI_LIST_PREPEND(edge->perm, qapi_perm); |
5d3b4e99 | 5726 | } |
cdb1cec8 | 5727 | if (flag & child->shared_perm) { |
9812e712 | 5728 | QAPI_LIST_PREPEND(edge->shared_perm, qapi_perm); |
5d3b4e99 VSO |
5729 | } |
5730 | } | |
5731 | ||
9812e712 | 5732 | QAPI_LIST_PREPEND(gr->graph->edges, edge); |
5d3b4e99 VSO |
5733 | } |
5734 | ||
5735 | ||
5736 | XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp) | |
5737 | { | |
5738 | BlockBackend *blk; | |
5739 | BlockJob *job; | |
5740 | BlockDriverState *bs; | |
5741 | BdrvChild *child; | |
5742 | XDbgBlockGraphConstructor *gr = xdbg_graph_new(); | |
5743 | ||
5744 | for (blk = blk_all_next(NULL); blk; blk = blk_all_next(blk)) { | |
5745 | char *allocated_name = NULL; | |
5746 | const char *name = blk_name(blk); | |
5747 | ||
5748 | if (!*name) { | |
5749 | name = allocated_name = blk_get_attached_dev_id(blk); | |
5750 | } | |
5751 | xdbg_graph_add_node(gr, blk, X_DBG_BLOCK_GRAPH_NODE_TYPE_BLOCK_BACKEND, | |
5752 | name); | |
5753 | g_free(allocated_name); | |
5754 | if (blk_root(blk)) { | |
5755 | xdbg_graph_add_edge(gr, blk, blk_root(blk)); | |
5756 | } | |
5757 | } | |
5758 | ||
5759 | for (job = block_job_next(NULL); job; job = block_job_next(job)) { | |
5760 | GSList *el; | |
5761 | ||
5762 | xdbg_graph_add_node(gr, job, X_DBG_BLOCK_GRAPH_NODE_TYPE_BLOCK_JOB, | |
5763 | job->job.id); | |
5764 | for (el = job->nodes; el; el = el->next) { | |
5765 | xdbg_graph_add_edge(gr, job, (BdrvChild *)el->data); | |
5766 | } | |
5767 | } | |
5768 | ||
5769 | QTAILQ_FOREACH(bs, &graph_bdrv_states, node_list) { | |
5770 | xdbg_graph_add_node(gr, bs, X_DBG_BLOCK_GRAPH_NODE_TYPE_BLOCK_DRIVER, | |
5771 | bs->node_name); | |
5772 | QLIST_FOREACH(child, &bs->children, next) { | |
5773 | xdbg_graph_add_edge(gr, bs, child); | |
5774 | } | |
5775 | } | |
5776 | ||
5777 | return xdbg_graph_finalize(gr); | |
5778 | } | |
5779 | ||
61007b31 SH |
5780 | BlockDriverState *bdrv_lookup_bs(const char *device, |
5781 | const char *node_name, | |
5782 | Error **errp) | |
5783 | { | |
5784 | BlockBackend *blk; | |
5785 | BlockDriverState *bs; | |
40b4f539 | 5786 | |
61007b31 SH |
5787 | if (device) { |
5788 | blk = blk_by_name(device); | |
40b4f539 | 5789 | |
61007b31 | 5790 | if (blk) { |
9f4ed6fb AG |
5791 | bs = blk_bs(blk); |
5792 | if (!bs) { | |
5433c24f | 5793 | error_setg(errp, "Device '%s' has no medium", device); |
5433c24f HR |
5794 | } |
5795 | ||
9f4ed6fb | 5796 | return bs; |
61007b31 SH |
5797 | } |
5798 | } | |
40b4f539 | 5799 | |
61007b31 SH |
5800 | if (node_name) { |
5801 | bs = bdrv_find_node(node_name); | |
6d519a5f | 5802 | |
61007b31 SH |
5803 | if (bs) { |
5804 | return bs; | |
5805 | } | |
40b4f539 KW |
5806 | } |
5807 | ||
785ec4b1 | 5808 | error_setg(errp, "Cannot find device=\'%s\' nor node-name=\'%s\'", |
61007b31 SH |
5809 | device ? device : "", |
5810 | node_name ? node_name : ""); | |
5811 | return NULL; | |
40b4f539 KW |
5812 | } |
5813 | ||
61007b31 SH |
5814 | /* If 'base' is in the same chain as 'top', return true. Otherwise, |
5815 | * return false. If either argument is NULL, return false. */ | |
5816 | bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base) | |
83f64091 | 5817 | { |
61007b31 | 5818 | while (top && top != base) { |
dcf3f9b2 | 5819 | top = bdrv_filter_or_cow_bs(top); |
02c50efe | 5820 | } |
61007b31 SH |
5821 | |
5822 | return top != NULL; | |
02c50efe FZ |
5823 | } |
5824 | ||
61007b31 | 5825 | BlockDriverState *bdrv_next_node(BlockDriverState *bs) |
02c50efe | 5826 | { |
61007b31 SH |
5827 | if (!bs) { |
5828 | return QTAILQ_FIRST(&graph_bdrv_states); | |
02c50efe | 5829 | } |
61007b31 | 5830 | return QTAILQ_NEXT(bs, node_list); |
83f64091 FB |
5831 | } |
5832 | ||
0f12264e KW |
5833 | BlockDriverState *bdrv_next_all_states(BlockDriverState *bs) |
5834 | { | |
5835 | if (!bs) { | |
5836 | return QTAILQ_FIRST(&all_bdrv_states); | |
5837 | } | |
5838 | return QTAILQ_NEXT(bs, bs_list); | |
5839 | } | |
5840 | ||
61007b31 | 5841 | const char *bdrv_get_node_name(const BlockDriverState *bs) |
83f64091 | 5842 | { |
61007b31 | 5843 | return bs->node_name; |
beac80cd FB |
5844 | } |
5845 | ||
1f0c461b | 5846 | const char *bdrv_get_parent_name(const BlockDriverState *bs) |
4c265bf9 KW |
5847 | { |
5848 | BdrvChild *c; | |
5849 | const char *name; | |
5850 | ||
5851 | /* If multiple parents have a name, just pick the first one. */ | |
5852 | QLIST_FOREACH(c, &bs->parents, next_parent) { | |
bd86fb99 HR |
5853 | if (c->klass->get_name) { |
5854 | name = c->klass->get_name(c); | |
4c265bf9 KW |
5855 | if (name && *name) { |
5856 | return name; | |
5857 | } | |
5858 | } | |
5859 | } | |
5860 | ||
5861 | return NULL; | |
5862 | } | |
5863 | ||
61007b31 SH |
5864 | /* TODO check what callers really want: bs->node_name or blk_name() */ |
5865 | const char *bdrv_get_device_name(const BlockDriverState *bs) | |
beac80cd | 5866 | { |
4c265bf9 | 5867 | return bdrv_get_parent_name(bs) ?: ""; |
f141eafe | 5868 | } |
83f64091 | 5869 | |
61007b31 SH |
5870 | /* This can be used to identify nodes that might not have a device |
5871 | * name associated. Since node and device names live in the same | |
5872 | * namespace, the result is unambiguous. The exception is if both are | |
5873 | * absent, then this returns an empty (non-null) string. */ | |
5874 | const char *bdrv_get_device_or_node_name(const BlockDriverState *bs) | |
f141eafe | 5875 | { |
4c265bf9 | 5876 | return bdrv_get_parent_name(bs) ?: bs->node_name; |
beac80cd | 5877 | } |
beac80cd | 5878 | |
61007b31 | 5879 | int bdrv_get_flags(BlockDriverState *bs) |
0b5a2445 | 5880 | { |
61007b31 | 5881 | return bs->open_flags; |
0b5a2445 PB |
5882 | } |
5883 | ||
61007b31 | 5884 | int bdrv_has_zero_init_1(BlockDriverState *bs) |
68485420 | 5885 | { |
61007b31 | 5886 | return 1; |
0b5a2445 PB |
5887 | } |
5888 | ||
61007b31 | 5889 | int bdrv_has_zero_init(BlockDriverState *bs) |
0b5a2445 | 5890 | { |
93393e69 HR |
5891 | BlockDriverState *filtered; |
5892 | ||
d470ad42 HR |
5893 | if (!bs->drv) { |
5894 | return 0; | |
5895 | } | |
0b5a2445 | 5896 | |
61007b31 SH |
5897 | /* If BS is a copy on write image, it is initialized to |
5898 | the contents of the base image, which may not be zeroes. */ | |
34778172 | 5899 | if (bdrv_cow_child(bs)) { |
61007b31 SH |
5900 | return 0; |
5901 | } | |
5902 | if (bs->drv->bdrv_has_zero_init) { | |
5903 | return bs->drv->bdrv_has_zero_init(bs); | |
0b5a2445 | 5904 | } |
93393e69 HR |
5905 | |
5906 | filtered = bdrv_filter_bs(bs); | |
5907 | if (filtered) { | |
5908 | return bdrv_has_zero_init(filtered); | |
5a612c00 | 5909 | } |
61007b31 SH |
5910 | |
5911 | /* safe default */ | |
5912 | return 0; | |
68485420 KW |
5913 | } |
5914 | ||
61007b31 | 5915 | bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs) |
68485420 | 5916 | { |
2f0342ef | 5917 | if (!(bs->open_flags & BDRV_O_UNMAP)) { |
61007b31 SH |
5918 | return false; |
5919 | } | |
68485420 | 5920 | |
e24d813b | 5921 | return bs->supported_zero_flags & BDRV_REQ_MAY_UNMAP; |
68485420 KW |
5922 | } |
5923 | ||
61007b31 SH |
5924 | void bdrv_get_backing_filename(BlockDriverState *bs, |
5925 | char *filename, int filename_size) | |
016f5cf6 | 5926 | { |
61007b31 SH |
5927 | pstrcpy(filename, filename_size, bs->backing_file); |
5928 | } | |
d318aea9 | 5929 | |
61007b31 SH |
5930 | int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) |
5931 | { | |
8b117001 | 5932 | int ret; |
61007b31 | 5933 | BlockDriver *drv = bs->drv; |
5a612c00 MP |
5934 | /* if bs->drv == NULL, bs is closed, so there's nothing to do here */ |
5935 | if (!drv) { | |
61007b31 | 5936 | return -ENOMEDIUM; |
5a612c00 MP |
5937 | } |
5938 | if (!drv->bdrv_get_info) { | |
93393e69 HR |
5939 | BlockDriverState *filtered = bdrv_filter_bs(bs); |
5940 | if (filtered) { | |
5941 | return bdrv_get_info(filtered, bdi); | |
5a612c00 | 5942 | } |
61007b31 | 5943 | return -ENOTSUP; |
5a612c00 | 5944 | } |
61007b31 | 5945 | memset(bdi, 0, sizeof(*bdi)); |
8b117001 VSO |
5946 | ret = drv->bdrv_get_info(bs, bdi); |
5947 | if (ret < 0) { | |
5948 | return ret; | |
5949 | } | |
5950 | ||
5951 | if (bdi->cluster_size > BDRV_MAX_ALIGNMENT) { | |
5952 | return -EINVAL; | |
5953 | } | |
5954 | ||
5955 | return 0; | |
61007b31 | 5956 | } |
016f5cf6 | 5957 | |
1bf6e9ca AS |
5958 | ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs, |
5959 | Error **errp) | |
61007b31 SH |
5960 | { |
5961 | BlockDriver *drv = bs->drv; | |
5962 | if (drv && drv->bdrv_get_specific_info) { | |
1bf6e9ca | 5963 | return drv->bdrv_get_specific_info(bs, errp); |
61007b31 SH |
5964 | } |
5965 | return NULL; | |
016f5cf6 AG |
5966 | } |
5967 | ||
d9245599 AN |
5968 | BlockStatsSpecific *bdrv_get_specific_stats(BlockDriverState *bs) |
5969 | { | |
5970 | BlockDriver *drv = bs->drv; | |
5971 | if (!drv || !drv->bdrv_get_specific_stats) { | |
5972 | return NULL; | |
5973 | } | |
5974 | return drv->bdrv_get_specific_stats(bs); | |
5975 | } | |
5976 | ||
a31939e6 | 5977 | void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event) |
4265d620 | 5978 | { |
61007b31 SH |
5979 | if (!bs || !bs->drv || !bs->drv->bdrv_debug_event) { |
5980 | return; | |
5981 | } | |
4265d620 | 5982 | |
61007b31 | 5983 | bs->drv->bdrv_debug_event(bs, event); |
4265d620 PB |
5984 | } |
5985 | ||
d10529a2 | 5986 | static BlockDriverState *bdrv_find_debug_node(BlockDriverState *bs) |
4265d620 | 5987 | { |
61007b31 | 5988 | while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) { |
f706a92f | 5989 | bs = bdrv_primary_bs(bs); |
61007b31 | 5990 | } |
4265d620 | 5991 | |
61007b31 | 5992 | if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) { |
d10529a2 VSO |
5993 | assert(bs->drv->bdrv_debug_remove_breakpoint); |
5994 | return bs; | |
5995 | } | |
5996 | ||
5997 | return NULL; | |
5998 | } | |
5999 | ||
6000 | int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, | |
6001 | const char *tag) | |
6002 | { | |
6003 | bs = bdrv_find_debug_node(bs); | |
6004 | if (bs) { | |
61007b31 SH |
6005 | return bs->drv->bdrv_debug_breakpoint(bs, event, tag); |
6006 | } | |
4265d620 | 6007 | |
61007b31 | 6008 | return -ENOTSUP; |
4265d620 PB |
6009 | } |
6010 | ||
61007b31 | 6011 | int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag) |
ea2384d3 | 6012 | { |
d10529a2 VSO |
6013 | bs = bdrv_find_debug_node(bs); |
6014 | if (bs) { | |
61007b31 SH |
6015 | return bs->drv->bdrv_debug_remove_breakpoint(bs, tag); |
6016 | } | |
6017 | ||
6018 | return -ENOTSUP; | |
eb852011 MA |
6019 | } |
6020 | ||
61007b31 | 6021 | int bdrv_debug_resume(BlockDriverState *bs, const char *tag) |
ce1a14dc | 6022 | { |
61007b31 | 6023 | while (bs && (!bs->drv || !bs->drv->bdrv_debug_resume)) { |
f706a92f | 6024 | bs = bdrv_primary_bs(bs); |
61007b31 | 6025 | } |
ce1a14dc | 6026 | |
61007b31 SH |
6027 | if (bs && bs->drv && bs->drv->bdrv_debug_resume) { |
6028 | return bs->drv->bdrv_debug_resume(bs, tag); | |
6029 | } | |
ce1a14dc | 6030 | |
61007b31 | 6031 | return -ENOTSUP; |
f197fe2b FZ |
6032 | } |
6033 | ||
61007b31 | 6034 | bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag) |
ce1a14dc | 6035 | { |
61007b31 | 6036 | while (bs && bs->drv && !bs->drv->bdrv_debug_is_suspended) { |
f706a92f | 6037 | bs = bdrv_primary_bs(bs); |
f197fe2b | 6038 | } |
19cb3738 | 6039 | |
61007b31 SH |
6040 | if (bs && bs->drv && bs->drv->bdrv_debug_is_suspended) { |
6041 | return bs->drv->bdrv_debug_is_suspended(bs, tag); | |
6042 | } | |
f9f05dc5 | 6043 | |
61007b31 SH |
6044 | return false; |
6045 | } | |
f9f05dc5 | 6046 | |
61007b31 SH |
6047 | /* backing_file can either be relative, or absolute, or a protocol. If it is |
6048 | * relative, it must be relative to the chain. So, passing in bs->filename | |
6049 | * from a BDS as backing_file should not be done, as that may be relative to | |
6050 | * the CWD rather than the chain. */ | |
6051 | BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, | |
6052 | const char *backing_file) | |
f9f05dc5 | 6053 | { |
61007b31 SH |
6054 | char *filename_full = NULL; |
6055 | char *backing_file_full = NULL; | |
6056 | char *filename_tmp = NULL; | |
6057 | int is_protocol = 0; | |
0b877d09 | 6058 | bool filenames_refreshed = false; |
61007b31 SH |
6059 | BlockDriverState *curr_bs = NULL; |
6060 | BlockDriverState *retval = NULL; | |
dcf3f9b2 | 6061 | BlockDriverState *bs_below; |
f9f05dc5 | 6062 | |
61007b31 SH |
6063 | if (!bs || !bs->drv || !backing_file) { |
6064 | return NULL; | |
f9f05dc5 KW |
6065 | } |
6066 | ||
61007b31 SH |
6067 | filename_full = g_malloc(PATH_MAX); |
6068 | backing_file_full = g_malloc(PATH_MAX); | |
f9f05dc5 | 6069 | |
61007b31 | 6070 | is_protocol = path_has_protocol(backing_file); |
f9f05dc5 | 6071 | |
dcf3f9b2 HR |
6072 | /* |
6073 | * Being largely a legacy function, skip any filters here | |
6074 | * (because filters do not have normal filenames, so they cannot | |
6075 | * match anyway; and allowing json:{} filenames is a bit out of | |
6076 | * scope). | |
6077 | */ | |
6078 | for (curr_bs = bdrv_skip_filters(bs); | |
6079 | bdrv_cow_child(curr_bs) != NULL; | |
6080 | curr_bs = bs_below) | |
6081 | { | |
6082 | bs_below = bdrv_backing_chain_next(curr_bs); | |
f9f05dc5 | 6083 | |
0b877d09 HR |
6084 | if (bdrv_backing_overridden(curr_bs)) { |
6085 | /* | |
6086 | * If the backing file was overridden, we can only compare | |
6087 | * directly against the backing node's filename. | |
6088 | */ | |
6089 | ||
6090 | if (!filenames_refreshed) { | |
6091 | /* | |
6092 | * This will automatically refresh all of the | |
6093 | * filenames in the rest of the backing chain, so we | |
6094 | * only need to do this once. | |
6095 | */ | |
6096 | bdrv_refresh_filename(bs_below); | |
6097 | filenames_refreshed = true; | |
6098 | } | |
6099 | ||
6100 | if (strcmp(backing_file, bs_below->filename) == 0) { | |
6101 | retval = bs_below; | |
6102 | break; | |
6103 | } | |
6104 | } else if (is_protocol || path_has_protocol(curr_bs->backing_file)) { | |
6105 | /* | |
6106 | * If either of the filename paths is actually a protocol, then | |
6107 | * compare unmodified paths; otherwise make paths relative. | |
6108 | */ | |
6b6833c1 HR |
6109 | char *backing_file_full_ret; |
6110 | ||
61007b31 | 6111 | if (strcmp(backing_file, curr_bs->backing_file) == 0) { |
dcf3f9b2 | 6112 | retval = bs_below; |
61007b31 SH |
6113 | break; |
6114 | } | |
418661e0 | 6115 | /* Also check against the full backing filename for the image */ |
6b6833c1 HR |
6116 | backing_file_full_ret = bdrv_get_full_backing_filename(curr_bs, |
6117 | NULL); | |
6118 | if (backing_file_full_ret) { | |
6119 | bool equal = strcmp(backing_file, backing_file_full_ret) == 0; | |
6120 | g_free(backing_file_full_ret); | |
6121 | if (equal) { | |
dcf3f9b2 | 6122 | retval = bs_below; |
418661e0 JC |
6123 | break; |
6124 | } | |
418661e0 | 6125 | } |
61007b31 SH |
6126 | } else { |
6127 | /* If not an absolute filename path, make it relative to the current | |
6128 | * image's filename path */ | |
2d9158ce HR |
6129 | filename_tmp = bdrv_make_absolute_filename(curr_bs, backing_file, |
6130 | NULL); | |
6131 | /* We are going to compare canonicalized absolute pathnames */ | |
6132 | if (!filename_tmp || !realpath(filename_tmp, filename_full)) { | |
6133 | g_free(filename_tmp); | |
61007b31 SH |
6134 | continue; |
6135 | } | |
2d9158ce | 6136 | g_free(filename_tmp); |
07f07615 | 6137 | |
61007b31 SH |
6138 | /* We need to make sure the backing filename we are comparing against |
6139 | * is relative to the current image filename (or absolute) */ | |
2d9158ce HR |
6140 | filename_tmp = bdrv_get_full_backing_filename(curr_bs, NULL); |
6141 | if (!filename_tmp || !realpath(filename_tmp, backing_file_full)) { | |
6142 | g_free(filename_tmp); | |
61007b31 SH |
6143 | continue; |
6144 | } | |
2d9158ce | 6145 | g_free(filename_tmp); |
eb489bb1 | 6146 | |
61007b31 | 6147 | if (strcmp(backing_file_full, filename_full) == 0) { |
dcf3f9b2 | 6148 | retval = bs_below; |
61007b31 SH |
6149 | break; |
6150 | } | |
6151 | } | |
eb489bb1 KW |
6152 | } |
6153 | ||
61007b31 SH |
6154 | g_free(filename_full); |
6155 | g_free(backing_file_full); | |
61007b31 SH |
6156 | return retval; |
6157 | } | |
6158 | ||
61007b31 SH |
6159 | void bdrv_init(void) |
6160 | { | |
6161 | module_call_init(MODULE_INIT_BLOCK); | |
6162 | } | |
29cdb251 | 6163 | |
61007b31 SH |
6164 | void bdrv_init_with_whitelist(void) |
6165 | { | |
6166 | use_bdrv_whitelist = 1; | |
6167 | bdrv_init(); | |
07f07615 PB |
6168 | } |
6169 | ||
21c2283e | 6170 | int coroutine_fn bdrv_co_invalidate_cache(BlockDriverState *bs, Error **errp) |
0f15423c | 6171 | { |
4417ab7a | 6172 | BdrvChild *child, *parent; |
5a8a30db KW |
6173 | Error *local_err = NULL; |
6174 | int ret; | |
9c98f145 | 6175 | BdrvDirtyBitmap *bm; |
5a8a30db | 6176 | |
3456a8d1 | 6177 | if (!bs->drv) { |
5416645f | 6178 | return -ENOMEDIUM; |
3456a8d1 KW |
6179 | } |
6180 | ||
16e977d5 | 6181 | QLIST_FOREACH(child, &bs->children, next) { |
2b148f39 | 6182 | bdrv_co_invalidate_cache(child->bs, &local_err); |
0d1c5c91 | 6183 | if (local_err) { |
0d1c5c91 | 6184 | error_propagate(errp, local_err); |
5416645f | 6185 | return -EINVAL; |
0d1c5c91 | 6186 | } |
5a8a30db | 6187 | } |
0d1c5c91 | 6188 | |
dafe0960 KW |
6189 | /* |
6190 | * Update permissions, they may differ for inactive nodes. | |
6191 | * | |
6192 | * Note that the required permissions of inactive images are always a | |
6193 | * subset of the permissions required after activating the image. This | |
6194 | * allows us to just get the permissions upfront without restricting | |
6195 | * drv->bdrv_invalidate_cache(). | |
6196 | * | |
6197 | * It also means that in error cases, we don't have to try and revert to | |
6198 | * the old permissions (which is an operation that could fail, too). We can | |
6199 | * just keep the extended permissions for the next time that an activation | |
6200 | * of the image is tried. | |
6201 | */ | |
7bb4941a KW |
6202 | if (bs->open_flags & BDRV_O_INACTIVE) { |
6203 | bs->open_flags &= ~BDRV_O_INACTIVE; | |
071b474f | 6204 | ret = bdrv_refresh_perms(bs, errp); |
7bb4941a | 6205 | if (ret < 0) { |
0d1c5c91 | 6206 | bs->open_flags |= BDRV_O_INACTIVE; |
5416645f | 6207 | return ret; |
0d1c5c91 | 6208 | } |
3456a8d1 | 6209 | |
7bb4941a KW |
6210 | if (bs->drv->bdrv_co_invalidate_cache) { |
6211 | bs->drv->bdrv_co_invalidate_cache(bs, &local_err); | |
6212 | if (local_err) { | |
6213 | bs->open_flags |= BDRV_O_INACTIVE; | |
6214 | error_propagate(errp, local_err); | |
5416645f | 6215 | return -EINVAL; |
7bb4941a KW |
6216 | } |
6217 | } | |
9c98f145 | 6218 | |
7bb4941a KW |
6219 | FOR_EACH_DIRTY_BITMAP(bs, bm) { |
6220 | bdrv_dirty_bitmap_skip_store(bm, false); | |
6221 | } | |
6222 | ||
6223 | ret = refresh_total_sectors(bs, bs->total_sectors); | |
6224 | if (ret < 0) { | |
6225 | bs->open_flags |= BDRV_O_INACTIVE; | |
6226 | error_setg_errno(errp, -ret, "Could not refresh total sector count"); | |
5416645f | 6227 | return ret; |
7bb4941a | 6228 | } |
5a8a30db | 6229 | } |
4417ab7a KW |
6230 | |
6231 | QLIST_FOREACH(parent, &bs->parents, next_parent) { | |
bd86fb99 HR |
6232 | if (parent->klass->activate) { |
6233 | parent->klass->activate(parent, &local_err); | |
4417ab7a | 6234 | if (local_err) { |
78fc3b3a | 6235 | bs->open_flags |= BDRV_O_INACTIVE; |
4417ab7a | 6236 | error_propagate(errp, local_err); |
5416645f | 6237 | return -EINVAL; |
4417ab7a KW |
6238 | } |
6239 | } | |
6240 | } | |
5416645f VSO |
6241 | |
6242 | return 0; | |
0f15423c AL |
6243 | } |
6244 | ||
5a8a30db | 6245 | void bdrv_invalidate_cache_all(Error **errp) |
0f15423c | 6246 | { |
7c8eece4 | 6247 | BlockDriverState *bs; |
88be7b4b | 6248 | BdrvNextIterator it; |
0f15423c | 6249 | |
88be7b4b | 6250 | for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { |
ed78cda3 | 6251 | AioContext *aio_context = bdrv_get_aio_context(bs); |
5416645f | 6252 | int ret; |
ed78cda3 SH |
6253 | |
6254 | aio_context_acquire(aio_context); | |
5416645f | 6255 | ret = bdrv_invalidate_cache(bs, errp); |
ed78cda3 | 6256 | aio_context_release(aio_context); |
5416645f | 6257 | if (ret < 0) { |
5e003f17 | 6258 | bdrv_next_cleanup(&it); |
5a8a30db KW |
6259 | return; |
6260 | } | |
0f15423c AL |
6261 | } |
6262 | } | |
6263 | ||
9e37271f KW |
6264 | static bool bdrv_has_bds_parent(BlockDriverState *bs, bool only_active) |
6265 | { | |
6266 | BdrvChild *parent; | |
6267 | ||
6268 | QLIST_FOREACH(parent, &bs->parents, next_parent) { | |
bd86fb99 | 6269 | if (parent->klass->parent_is_bds) { |
9e37271f KW |
6270 | BlockDriverState *parent_bs = parent->opaque; |
6271 | if (!only_active || !(parent_bs->open_flags & BDRV_O_INACTIVE)) { | |
6272 | return true; | |
6273 | } | |
6274 | } | |
6275 | } | |
6276 | ||
6277 | return false; | |
6278 | } | |
6279 | ||
6280 | static int bdrv_inactivate_recurse(BlockDriverState *bs) | |
76b1c7fe | 6281 | { |
cfa1a572 | 6282 | BdrvChild *child, *parent; |
76b1c7fe KW |
6283 | int ret; |
6284 | ||
d470ad42 HR |
6285 | if (!bs->drv) { |
6286 | return -ENOMEDIUM; | |
6287 | } | |
6288 | ||
9e37271f KW |
6289 | /* Make sure that we don't inactivate a child before its parent. |
6290 | * It will be covered by recursion from the yet active parent. */ | |
6291 | if (bdrv_has_bds_parent(bs, true)) { | |
6292 | return 0; | |
6293 | } | |
6294 | ||
6295 | assert(!(bs->open_flags & BDRV_O_INACTIVE)); | |
6296 | ||
6297 | /* Inactivate this node */ | |
6298 | if (bs->drv->bdrv_inactivate) { | |
76b1c7fe KW |
6299 | ret = bs->drv->bdrv_inactivate(bs); |
6300 | if (ret < 0) { | |
6301 | return ret; | |
6302 | } | |
6303 | } | |
6304 | ||
9e37271f | 6305 | QLIST_FOREACH(parent, &bs->parents, next_parent) { |
bd86fb99 HR |
6306 | if (parent->klass->inactivate) { |
6307 | ret = parent->klass->inactivate(parent); | |
9e37271f KW |
6308 | if (ret < 0) { |
6309 | return ret; | |
cfa1a572 KW |
6310 | } |
6311 | } | |
9e37271f | 6312 | } |
9c5e6594 | 6313 | |
9e37271f | 6314 | bs->open_flags |= BDRV_O_INACTIVE; |
7d5b5261 | 6315 | |
bb87e4d1 VSO |
6316 | /* |
6317 | * Update permissions, they may differ for inactive nodes. | |
6318 | * We only tried to loosen restrictions, so errors are not fatal, ignore | |
6319 | * them. | |
6320 | */ | |
071b474f | 6321 | bdrv_refresh_perms(bs, NULL); |
9e37271f KW |
6322 | |
6323 | /* Recursively inactivate children */ | |
38701b6a | 6324 | QLIST_FOREACH(child, &bs->children, next) { |
9e37271f | 6325 | ret = bdrv_inactivate_recurse(child->bs); |
38701b6a KW |
6326 | if (ret < 0) { |
6327 | return ret; | |
6328 | } | |
6329 | } | |
6330 | ||
76b1c7fe KW |
6331 | return 0; |
6332 | } | |
6333 | ||
6334 | int bdrv_inactivate_all(void) | |
6335 | { | |
79720af6 | 6336 | BlockDriverState *bs = NULL; |
88be7b4b | 6337 | BdrvNextIterator it; |
aad0b7a0 | 6338 | int ret = 0; |
bd6458e4 | 6339 | GSList *aio_ctxs = NULL, *ctx; |
76b1c7fe | 6340 | |
88be7b4b | 6341 | for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { |
bd6458e4 PB |
6342 | AioContext *aio_context = bdrv_get_aio_context(bs); |
6343 | ||
6344 | if (!g_slist_find(aio_ctxs, aio_context)) { | |
6345 | aio_ctxs = g_slist_prepend(aio_ctxs, aio_context); | |
6346 | aio_context_acquire(aio_context); | |
6347 | } | |
aad0b7a0 | 6348 | } |
76b1c7fe | 6349 | |
9e37271f KW |
6350 | for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) { |
6351 | /* Nodes with BDS parents are covered by recursion from the last | |
6352 | * parent that gets inactivated. Don't inactivate them a second | |
6353 | * time if that has already happened. */ | |
6354 | if (bdrv_has_bds_parent(bs, false)) { | |
6355 | continue; | |
6356 | } | |
6357 | ret = bdrv_inactivate_recurse(bs); | |
6358 | if (ret < 0) { | |
6359 | bdrv_next_cleanup(&it); | |
6360 | goto out; | |
76b1c7fe KW |
6361 | } |
6362 | } | |
6363 | ||
aad0b7a0 | 6364 | out: |
bd6458e4 PB |
6365 | for (ctx = aio_ctxs; ctx != NULL; ctx = ctx->next) { |
6366 | AioContext *aio_context = ctx->data; | |
6367 | aio_context_release(aio_context); | |
aad0b7a0 | 6368 | } |
bd6458e4 | 6369 | g_slist_free(aio_ctxs); |
aad0b7a0 FZ |
6370 | |
6371 | return ret; | |
76b1c7fe KW |
6372 | } |
6373 | ||
19cb3738 FB |
6374 | /**************************************************************/ |
6375 | /* removable device support */ | |
6376 | ||
6377 | /** | |
6378 | * Return TRUE if the media is present | |
6379 | */ | |
e031f750 | 6380 | bool bdrv_is_inserted(BlockDriverState *bs) |
19cb3738 FB |
6381 | { |
6382 | BlockDriver *drv = bs->drv; | |
28d7a789 | 6383 | BdrvChild *child; |
a1aff5bf | 6384 | |
e031f750 HR |
6385 | if (!drv) { |
6386 | return false; | |
6387 | } | |
28d7a789 HR |
6388 | if (drv->bdrv_is_inserted) { |
6389 | return drv->bdrv_is_inserted(bs); | |
6390 | } | |
6391 | QLIST_FOREACH(child, &bs->children, next) { | |
6392 | if (!bdrv_is_inserted(child->bs)) { | |
6393 | return false; | |
6394 | } | |
e031f750 | 6395 | } |
28d7a789 | 6396 | return true; |
19cb3738 FB |
6397 | } |
6398 | ||
19cb3738 FB |
6399 | /** |
6400 | * If eject_flag is TRUE, eject the media. Otherwise, close the tray | |
6401 | */ | |
f36f3949 | 6402 | void bdrv_eject(BlockDriverState *bs, bool eject_flag) |
19cb3738 FB |
6403 | { |
6404 | BlockDriver *drv = bs->drv; | |
19cb3738 | 6405 | |
822e1cd1 MA |
6406 | if (drv && drv->bdrv_eject) { |
6407 | drv->bdrv_eject(bs, eject_flag); | |
19cb3738 FB |
6408 | } |
6409 | } | |
6410 | ||
19cb3738 FB |
6411 | /** |
6412 | * Lock or unlock the media (if it is locked, the user won't be able | |
6413 | * to eject it manually). | |
6414 | */ | |
025e849a | 6415 | void bdrv_lock_medium(BlockDriverState *bs, bool locked) |
19cb3738 FB |
6416 | { |
6417 | BlockDriver *drv = bs->drv; | |
6418 | ||
025e849a | 6419 | trace_bdrv_lock_medium(bs, locked); |
b8c6d095 | 6420 | |
025e849a MA |
6421 | if (drv && drv->bdrv_lock_medium) { |
6422 | drv->bdrv_lock_medium(bs, locked); | |
19cb3738 FB |
6423 | } |
6424 | } | |
985a03b0 | 6425 | |
9fcb0251 FZ |
6426 | /* Get a reference to bs */ |
6427 | void bdrv_ref(BlockDriverState *bs) | |
6428 | { | |
6429 | bs->refcnt++; | |
6430 | } | |
6431 | ||
6432 | /* Release a previously grabbed reference to bs. | |
6433 | * If after releasing, reference count is zero, the BlockDriverState is | |
6434 | * deleted. */ | |
6435 | void bdrv_unref(BlockDriverState *bs) | |
6436 | { | |
9a4d5ca6 JC |
6437 | if (!bs) { |
6438 | return; | |
6439 | } | |
9fcb0251 FZ |
6440 | assert(bs->refcnt > 0); |
6441 | if (--bs->refcnt == 0) { | |
6442 | bdrv_delete(bs); | |
6443 | } | |
6444 | } | |
6445 | ||
fbe40ff7 FZ |
6446 | struct BdrvOpBlocker { |
6447 | Error *reason; | |
6448 | QLIST_ENTRY(BdrvOpBlocker) list; | |
6449 | }; | |
6450 | ||
6451 | bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp) | |
6452 | { | |
6453 | BdrvOpBlocker *blocker; | |
6454 | assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); | |
6455 | if (!QLIST_EMPTY(&bs->op_blockers[op])) { | |
6456 | blocker = QLIST_FIRST(&bs->op_blockers[op]); | |
4b576648 MA |
6457 | error_propagate_prepend(errp, error_copy(blocker->reason), |
6458 | "Node '%s' is busy: ", | |
6459 | bdrv_get_device_or_node_name(bs)); | |
fbe40ff7 FZ |
6460 | return true; |
6461 | } | |
6462 | return false; | |
6463 | } | |
6464 | ||
6465 | void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason) | |
6466 | { | |
6467 | BdrvOpBlocker *blocker; | |
6468 | assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); | |
6469 | ||
5839e53b | 6470 | blocker = g_new0(BdrvOpBlocker, 1); |
fbe40ff7 FZ |
6471 | blocker->reason = reason; |
6472 | QLIST_INSERT_HEAD(&bs->op_blockers[op], blocker, list); | |
6473 | } | |
6474 | ||
6475 | void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason) | |
6476 | { | |
6477 | BdrvOpBlocker *blocker, *next; | |
6478 | assert((int) op >= 0 && op < BLOCK_OP_TYPE_MAX); | |
6479 | QLIST_FOREACH_SAFE(blocker, &bs->op_blockers[op], list, next) { | |
6480 | if (blocker->reason == reason) { | |
6481 | QLIST_REMOVE(blocker, list); | |
6482 | g_free(blocker); | |
6483 | } | |
6484 | } | |
6485 | } | |
6486 | ||
6487 | void bdrv_op_block_all(BlockDriverState *bs, Error *reason) | |
6488 | { | |
6489 | int i; | |
6490 | for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { | |
6491 | bdrv_op_block(bs, i, reason); | |
6492 | } | |
6493 | } | |
6494 | ||
6495 | void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason) | |
6496 | { | |
6497 | int i; | |
6498 | for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { | |
6499 | bdrv_op_unblock(bs, i, reason); | |
6500 | } | |
6501 | } | |
6502 | ||
6503 | bool bdrv_op_blocker_is_empty(BlockDriverState *bs) | |
6504 | { | |
6505 | int i; | |
6506 | ||
6507 | for (i = 0; i < BLOCK_OP_TYPE_MAX; i++) { | |
6508 | if (!QLIST_EMPTY(&bs->op_blockers[i])) { | |
6509 | return false; | |
6510 | } | |
6511 | } | |
6512 | return true; | |
6513 | } | |
6514 | ||
d92ada22 LC |
6515 | void bdrv_img_create(const char *filename, const char *fmt, |
6516 | const char *base_filename, const char *base_fmt, | |
9217283d FZ |
6517 | char *options, uint64_t img_size, int flags, bool quiet, |
6518 | Error **errp) | |
f88e1a42 | 6519 | { |
83d0521a CL |
6520 | QemuOptsList *create_opts = NULL; |
6521 | QemuOpts *opts = NULL; | |
6522 | const char *backing_fmt, *backing_file; | |
6523 | int64_t size; | |
f88e1a42 | 6524 | BlockDriver *drv, *proto_drv; |
cc84d90f | 6525 | Error *local_err = NULL; |
f88e1a42 JS |
6526 | int ret = 0; |
6527 | ||
6528 | /* Find driver and parse its options */ | |
6529 | drv = bdrv_find_format(fmt); | |
6530 | if (!drv) { | |
71c79813 | 6531 | error_setg(errp, "Unknown file format '%s'", fmt); |
d92ada22 | 6532 | return; |
f88e1a42 JS |
6533 | } |
6534 | ||
b65a5e12 | 6535 | proto_drv = bdrv_find_protocol(filename, true, errp); |
f88e1a42 | 6536 | if (!proto_drv) { |
d92ada22 | 6537 | return; |
f88e1a42 JS |
6538 | } |
6539 | ||
c6149724 HR |
6540 | if (!drv->create_opts) { |
6541 | error_setg(errp, "Format driver '%s' does not support image creation", | |
6542 | drv->format_name); | |
6543 | return; | |
6544 | } | |
6545 | ||
5a5e7f8c ML |
6546 | if (!proto_drv->create_opts) { |
6547 | error_setg(errp, "Protocol driver '%s' does not support image creation", | |
6548 | proto_drv->format_name); | |
6549 | return; | |
6550 | } | |
6551 | ||
f6dc1c31 | 6552 | /* Create parameter list */ |
c282e1fd | 6553 | create_opts = qemu_opts_append(create_opts, drv->create_opts); |
5a5e7f8c | 6554 | create_opts = qemu_opts_append(create_opts, proto_drv->create_opts); |
f88e1a42 | 6555 | |
83d0521a | 6556 | opts = qemu_opts_create(create_opts, NULL, 0, &error_abort); |
f88e1a42 JS |
6557 | |
6558 | /* Parse -o options */ | |
6559 | if (options) { | |
a5f9b9df | 6560 | if (!qemu_opts_do_parse(opts, options, NULL, errp)) { |
f88e1a42 JS |
6561 | goto out; |
6562 | } | |
6563 | } | |
6564 | ||
f6dc1c31 KW |
6565 | if (!qemu_opt_get(opts, BLOCK_OPT_SIZE)) { |
6566 | qemu_opt_set_number(opts, BLOCK_OPT_SIZE, img_size, &error_abort); | |
6567 | } else if (img_size != UINT64_C(-1)) { | |
6568 | error_setg(errp, "The image size must be specified only once"); | |
6569 | goto out; | |
6570 | } | |
6571 | ||
f88e1a42 | 6572 | if (base_filename) { |
235e59cf | 6573 | if (!qemu_opt_set(opts, BLOCK_OPT_BACKING_FILE, base_filename, |
3882578b | 6574 | NULL)) { |
71c79813 LC |
6575 | error_setg(errp, "Backing file not supported for file format '%s'", |
6576 | fmt); | |
f88e1a42 JS |
6577 | goto out; |
6578 | } | |
6579 | } | |
6580 | ||
6581 | if (base_fmt) { | |
3882578b | 6582 | if (!qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, base_fmt, NULL)) { |
71c79813 LC |
6583 | error_setg(errp, "Backing file format not supported for file " |
6584 | "format '%s'", fmt); | |
f88e1a42 JS |
6585 | goto out; |
6586 | } | |
6587 | } | |
6588 | ||
83d0521a CL |
6589 | backing_file = qemu_opt_get(opts, BLOCK_OPT_BACKING_FILE); |
6590 | if (backing_file) { | |
6591 | if (!strcmp(filename, backing_file)) { | |
71c79813 LC |
6592 | error_setg(errp, "Error: Trying to create an image with the " |
6593 | "same filename as the backing file"); | |
792da93a JS |
6594 | goto out; |
6595 | } | |
975a7bd2 CK |
6596 | if (backing_file[0] == '\0') { |
6597 | error_setg(errp, "Expected backing file name, got empty string"); | |
6598 | goto out; | |
6599 | } | |
792da93a JS |
6600 | } |
6601 | ||
83d0521a | 6602 | backing_fmt = qemu_opt_get(opts, BLOCK_OPT_BACKING_FMT); |
f88e1a42 | 6603 | |
6e6e55f5 JS |
6604 | /* The size for the image must always be specified, unless we have a backing |
6605 | * file and we have not been forbidden from opening it. */ | |
a8b42a1c | 6606 | size = qemu_opt_get_size(opts, BLOCK_OPT_SIZE, img_size); |
6e6e55f5 JS |
6607 | if (backing_file && !(flags & BDRV_O_NO_BACKING)) { |
6608 | BlockDriverState *bs; | |
645ae7d8 | 6609 | char *full_backing; |
6e6e55f5 JS |
6610 | int back_flags; |
6611 | QDict *backing_options = NULL; | |
6612 | ||
645ae7d8 HR |
6613 | full_backing = |
6614 | bdrv_get_full_backing_filename_from_filename(filename, backing_file, | |
6615 | &local_err); | |
6e6e55f5 | 6616 | if (local_err) { |
6e6e55f5 JS |
6617 | goto out; |
6618 | } | |
645ae7d8 | 6619 | assert(full_backing); |
29168018 | 6620 | |
6e6e55f5 JS |
6621 | /* backing files always opened read-only */ |
6622 | back_flags = flags; | |
6623 | back_flags &= ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING); | |
f88e1a42 | 6624 | |
cc954f01 | 6625 | backing_options = qdict_new(); |
6e6e55f5 | 6626 | if (backing_fmt) { |
6e6e55f5 JS |
6627 | qdict_put_str(backing_options, "driver", backing_fmt); |
6628 | } | |
cc954f01 | 6629 | qdict_put_bool(backing_options, BDRV_OPT_FORCE_SHARE, true); |
e6641719 | 6630 | |
6e6e55f5 JS |
6631 | bs = bdrv_open(full_backing, NULL, backing_options, back_flags, |
6632 | &local_err); | |
6633 | g_free(full_backing); | |
add8200d EB |
6634 | if (!bs) { |
6635 | error_append_hint(&local_err, "Could not open backing image.\n"); | |
6e6e55f5 JS |
6636 | goto out; |
6637 | } else { | |
d9f059aa EB |
6638 | if (!backing_fmt) { |
6639 | warn_report("Deprecated use of backing file without explicit " | |
6640 | "backing format (detected format of %s)", | |
6641 | bs->drv->format_name); | |
6642 | if (bs->drv != &bdrv_raw) { | |
6643 | /* | |
6644 | * A probe of raw deserves the most attention: | |
6645 | * leaving the backing format out of the image | |
6646 | * will ensure bs->probed is set (ensuring we | |
6647 | * don't accidentally commit into the backing | |
6648 | * file), and allow more spots to warn the users | |
6649 | * to fix their toolchain when opening this image | |
6650 | * later. For other images, we can safely record | |
6651 | * the format that we probed. | |
6652 | */ | |
6653 | backing_fmt = bs->drv->format_name; | |
6654 | qemu_opt_set(opts, BLOCK_OPT_BACKING_FMT, backing_fmt, | |
6655 | NULL); | |
6656 | } | |
6657 | } | |
6e6e55f5 JS |
6658 | if (size == -1) { |
6659 | /* Opened BS, have no size */ | |
6660 | size = bdrv_getlength(bs); | |
6661 | if (size < 0) { | |
6662 | error_setg_errno(errp, -size, "Could not get size of '%s'", | |
6663 | backing_file); | |
6664 | bdrv_unref(bs); | |
6665 | goto out; | |
6666 | } | |
6667 | qemu_opt_set_number(opts, BLOCK_OPT_SIZE, size, &error_abort); | |
52bf1e72 | 6668 | } |
66f6b814 | 6669 | bdrv_unref(bs); |
f88e1a42 | 6670 | } |
d9f059aa EB |
6671 | /* (backing_file && !(flags & BDRV_O_NO_BACKING)) */ |
6672 | } else if (backing_file && !backing_fmt) { | |
6673 | warn_report("Deprecated use of unopened backing file without " | |
6674 | "explicit backing format, use of this image requires " | |
6675 | "potentially unsafe format probing"); | |
6676 | } | |
6e6e55f5 JS |
6677 | |
6678 | if (size == -1) { | |
6679 | error_setg(errp, "Image creation needs a size parameter"); | |
6680 | goto out; | |
f88e1a42 JS |
6681 | } |
6682 | ||
f382d43a | 6683 | if (!quiet) { |
fe646693 | 6684 | printf("Formatting '%s', fmt=%s ", filename, fmt); |
43c5d8f8 | 6685 | qemu_opts_print(opts, " "); |
f382d43a | 6686 | puts(""); |
4e2f4418 | 6687 | fflush(stdout); |
f382d43a | 6688 | } |
83d0521a | 6689 | |
c282e1fd | 6690 | ret = bdrv_create(drv, filename, opts, &local_err); |
83d0521a | 6691 | |
cc84d90f HR |
6692 | if (ret == -EFBIG) { |
6693 | /* This is generally a better message than whatever the driver would | |
6694 | * deliver (especially because of the cluster_size_hint), since that | |
6695 | * is most probably not much different from "image too large". */ | |
6696 | const char *cluster_size_hint = ""; | |
83d0521a | 6697 | if (qemu_opt_get_size(opts, BLOCK_OPT_CLUSTER_SIZE, 0)) { |
cc84d90f | 6698 | cluster_size_hint = " (try using a larger cluster size)"; |
f88e1a42 | 6699 | } |
cc84d90f HR |
6700 | error_setg(errp, "The image size is too large for file format '%s'" |
6701 | "%s", fmt, cluster_size_hint); | |
6702 | error_free(local_err); | |
6703 | local_err = NULL; | |
f88e1a42 JS |
6704 | } |
6705 | ||
6706 | out: | |
83d0521a CL |
6707 | qemu_opts_del(opts); |
6708 | qemu_opts_free(create_opts); | |
621ff94d | 6709 | error_propagate(errp, local_err); |
f88e1a42 | 6710 | } |
85d126f3 SH |
6711 | |
6712 | AioContext *bdrv_get_aio_context(BlockDriverState *bs) | |
6713 | { | |
33f2a757 | 6714 | return bs ? bs->aio_context : qemu_get_aio_context(); |
dcd04228 SH |
6715 | } |
6716 | ||
e336fd4c KW |
6717 | AioContext *coroutine_fn bdrv_co_enter(BlockDriverState *bs) |
6718 | { | |
6719 | Coroutine *self = qemu_coroutine_self(); | |
6720 | AioContext *old_ctx = qemu_coroutine_get_aio_context(self); | |
6721 | AioContext *new_ctx; | |
6722 | ||
6723 | /* | |
6724 | * Increase bs->in_flight to ensure that this operation is completed before | |
6725 | * moving the node to a different AioContext. Read new_ctx only afterwards. | |
6726 | */ | |
6727 | bdrv_inc_in_flight(bs); | |
6728 | ||
6729 | new_ctx = bdrv_get_aio_context(bs); | |
6730 | aio_co_reschedule_self(new_ctx); | |
6731 | return old_ctx; | |
6732 | } | |
6733 | ||
6734 | void coroutine_fn bdrv_co_leave(BlockDriverState *bs, AioContext *old_ctx) | |
6735 | { | |
6736 | aio_co_reschedule_self(old_ctx); | |
6737 | bdrv_dec_in_flight(bs); | |
6738 | } | |
6739 | ||
18c6ac1c KW |
6740 | void coroutine_fn bdrv_co_lock(BlockDriverState *bs) |
6741 | { | |
6742 | AioContext *ctx = bdrv_get_aio_context(bs); | |
6743 | ||
6744 | /* In the main thread, bs->aio_context won't change concurrently */ | |
6745 | assert(qemu_get_current_aio_context() == qemu_get_aio_context()); | |
6746 | ||
6747 | /* | |
6748 | * We're in coroutine context, so we already hold the lock of the main | |
6749 | * loop AioContext. Don't lock it twice to avoid deadlocks. | |
6750 | */ | |
6751 | assert(qemu_in_coroutine()); | |
6752 | if (ctx != qemu_get_aio_context()) { | |
6753 | aio_context_acquire(ctx); | |
6754 | } | |
6755 | } | |
6756 | ||
6757 | void coroutine_fn bdrv_co_unlock(BlockDriverState *bs) | |
6758 | { | |
6759 | AioContext *ctx = bdrv_get_aio_context(bs); | |
6760 | ||
6761 | assert(qemu_in_coroutine()); | |
6762 | if (ctx != qemu_get_aio_context()) { | |
6763 | aio_context_release(ctx); | |
6764 | } | |
6765 | } | |
6766 | ||
052a7572 FZ |
6767 | void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co) |
6768 | { | |
6769 | aio_co_enter(bdrv_get_aio_context(bs), co); | |
6770 | } | |
6771 | ||
e8a095da SH |
6772 | static void bdrv_do_remove_aio_context_notifier(BdrvAioNotifier *ban) |
6773 | { | |
6774 | QLIST_REMOVE(ban, list); | |
6775 | g_free(ban); | |
6776 | } | |
6777 | ||
a3a683c3 | 6778 | static void bdrv_detach_aio_context(BlockDriverState *bs) |
dcd04228 | 6779 | { |
e8a095da | 6780 | BdrvAioNotifier *baf, *baf_tmp; |
33384421 | 6781 | |
e8a095da SH |
6782 | assert(!bs->walking_aio_notifiers); |
6783 | bs->walking_aio_notifiers = true; | |
6784 | QLIST_FOREACH_SAFE(baf, &bs->aio_notifiers, list, baf_tmp) { | |
6785 | if (baf->deleted) { | |
6786 | bdrv_do_remove_aio_context_notifier(baf); | |
6787 | } else { | |
6788 | baf->detach_aio_context(baf->opaque); | |
6789 | } | |
33384421 | 6790 | } |
e8a095da SH |
6791 | /* Never mind iterating again to check for ->deleted. bdrv_close() will |
6792 | * remove remaining aio notifiers if we aren't called again. | |
6793 | */ | |
6794 | bs->walking_aio_notifiers = false; | |
33384421 | 6795 | |
1bffe1ae | 6796 | if (bs->drv && bs->drv->bdrv_detach_aio_context) { |
dcd04228 SH |
6797 | bs->drv->bdrv_detach_aio_context(bs); |
6798 | } | |
dcd04228 | 6799 | |
e64f25f3 KW |
6800 | if (bs->quiesce_counter) { |
6801 | aio_enable_external(bs->aio_context); | |
6802 | } | |
dcd04228 SH |
6803 | bs->aio_context = NULL; |
6804 | } | |
6805 | ||
a3a683c3 KW |
6806 | static void bdrv_attach_aio_context(BlockDriverState *bs, |
6807 | AioContext *new_context) | |
dcd04228 | 6808 | { |
e8a095da | 6809 | BdrvAioNotifier *ban, *ban_tmp; |
33384421 | 6810 | |
e64f25f3 KW |
6811 | if (bs->quiesce_counter) { |
6812 | aio_disable_external(new_context); | |
6813 | } | |
6814 | ||
dcd04228 SH |
6815 | bs->aio_context = new_context; |
6816 | ||
1bffe1ae | 6817 | if (bs->drv && bs->drv->bdrv_attach_aio_context) { |
dcd04228 SH |
6818 | bs->drv->bdrv_attach_aio_context(bs, new_context); |
6819 | } | |
33384421 | 6820 | |
e8a095da SH |
6821 | assert(!bs->walking_aio_notifiers); |
6822 | bs->walking_aio_notifiers = true; | |
6823 | QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_tmp) { | |
6824 | if (ban->deleted) { | |
6825 | bdrv_do_remove_aio_context_notifier(ban); | |
6826 | } else { | |
6827 | ban->attached_aio_context(new_context, ban->opaque); | |
6828 | } | |
33384421 | 6829 | } |
e8a095da | 6830 | bs->walking_aio_notifiers = false; |
dcd04228 SH |
6831 | } |
6832 | ||
42a65f02 KW |
6833 | /* |
6834 | * Changes the AioContext used for fd handlers, timers, and BHs by this | |
6835 | * BlockDriverState and all its children and parents. | |
6836 | * | |
43eaaaef HR |
6837 | * Must be called from the main AioContext. |
6838 | * | |
42a65f02 KW |
6839 | * The caller must own the AioContext lock for the old AioContext of bs, but it |
6840 | * must not own the AioContext lock for new_context (unless new_context is the | |
6841 | * same as the current context of bs). | |
6842 | * | |
6843 | * @ignore will accumulate all visited BdrvChild object. The caller is | |
6844 | * responsible for freeing the list afterwards. | |
6845 | */ | |
53a7d041 KW |
6846 | void bdrv_set_aio_context_ignore(BlockDriverState *bs, |
6847 | AioContext *new_context, GSList **ignore) | |
dcd04228 | 6848 | { |
e037c09c | 6849 | AioContext *old_context = bdrv_get_aio_context(bs); |
722d8e73 SL |
6850 | GSList *children_to_process = NULL; |
6851 | GSList *parents_to_process = NULL; | |
6852 | GSList *entry; | |
6853 | BdrvChild *child, *parent; | |
0d83708a | 6854 | |
43eaaaef HR |
6855 | g_assert(qemu_get_current_aio_context() == qemu_get_aio_context()); |
6856 | ||
e037c09c | 6857 | if (old_context == new_context) { |
57830a49 DP |
6858 | return; |
6859 | } | |
6860 | ||
d70d5954 | 6861 | bdrv_drained_begin(bs); |
0d83708a KW |
6862 | |
6863 | QLIST_FOREACH(child, &bs->children, next) { | |
53a7d041 KW |
6864 | if (g_slist_find(*ignore, child)) { |
6865 | continue; | |
6866 | } | |
6867 | *ignore = g_slist_prepend(*ignore, child); | |
722d8e73 | 6868 | children_to_process = g_slist_prepend(children_to_process, child); |
53a7d041 | 6869 | } |
722d8e73 SL |
6870 | |
6871 | QLIST_FOREACH(parent, &bs->parents, next_parent) { | |
6872 | if (g_slist_find(*ignore, parent)) { | |
53a7d041 KW |
6873 | continue; |
6874 | } | |
722d8e73 SL |
6875 | *ignore = g_slist_prepend(*ignore, parent); |
6876 | parents_to_process = g_slist_prepend(parents_to_process, parent); | |
6877 | } | |
6878 | ||
6879 | for (entry = children_to_process; | |
6880 | entry != NULL; | |
6881 | entry = g_slist_next(entry)) { | |
6882 | child = entry->data; | |
6883 | bdrv_set_aio_context_ignore(child->bs, new_context, ignore); | |
6884 | } | |
6885 | g_slist_free(children_to_process); | |
6886 | ||
6887 | for (entry = parents_to_process; | |
6888 | entry != NULL; | |
6889 | entry = g_slist_next(entry)) { | |
6890 | parent = entry->data; | |
6891 | assert(parent->klass->set_aio_ctx); | |
6892 | parent->klass->set_aio_ctx(parent, new_context, ignore); | |
0d83708a | 6893 | } |
722d8e73 | 6894 | g_slist_free(parents_to_process); |
0d83708a | 6895 | |
dcd04228 SH |
6896 | bdrv_detach_aio_context(bs); |
6897 | ||
e037c09c | 6898 | /* Acquire the new context, if necessary */ |
43eaaaef | 6899 | if (qemu_get_aio_context() != new_context) { |
e037c09c HR |
6900 | aio_context_acquire(new_context); |
6901 | } | |
6902 | ||
dcd04228 | 6903 | bdrv_attach_aio_context(bs, new_context); |
e037c09c HR |
6904 | |
6905 | /* | |
6906 | * If this function was recursively called from | |
6907 | * bdrv_set_aio_context_ignore(), there may be nodes in the | |
6908 | * subtree that have not yet been moved to the new AioContext. | |
6909 | * Release the old one so bdrv_drained_end() can poll them. | |
6910 | */ | |
43eaaaef | 6911 | if (qemu_get_aio_context() != old_context) { |
e037c09c HR |
6912 | aio_context_release(old_context); |
6913 | } | |
6914 | ||
d70d5954 | 6915 | bdrv_drained_end(bs); |
e037c09c | 6916 | |
43eaaaef | 6917 | if (qemu_get_aio_context() != old_context) { |
e037c09c HR |
6918 | aio_context_acquire(old_context); |
6919 | } | |
43eaaaef | 6920 | if (qemu_get_aio_context() != new_context) { |
e037c09c HR |
6921 | aio_context_release(new_context); |
6922 | } | |
85d126f3 | 6923 | } |
d616b224 | 6924 | |
5d231849 KW |
6925 | static bool bdrv_parent_can_set_aio_context(BdrvChild *c, AioContext *ctx, |
6926 | GSList **ignore, Error **errp) | |
6927 | { | |
6928 | if (g_slist_find(*ignore, c)) { | |
6929 | return true; | |
6930 | } | |
6931 | *ignore = g_slist_prepend(*ignore, c); | |
6932 | ||
bd86fb99 HR |
6933 | /* |
6934 | * A BdrvChildClass that doesn't handle AioContext changes cannot | |
6935 | * tolerate any AioContext changes | |
6936 | */ | |
6937 | if (!c->klass->can_set_aio_ctx) { | |
5d231849 KW |
6938 | char *user = bdrv_child_user_desc(c); |
6939 | error_setg(errp, "Changing iothreads is not supported by %s", user); | |
6940 | g_free(user); | |
6941 | return false; | |
6942 | } | |
bd86fb99 | 6943 | if (!c->klass->can_set_aio_ctx(c, ctx, ignore, errp)) { |
5d231849 KW |
6944 | assert(!errp || *errp); |
6945 | return false; | |
6946 | } | |
6947 | return true; | |
6948 | } | |
6949 | ||
6950 | bool bdrv_child_can_set_aio_context(BdrvChild *c, AioContext *ctx, | |
6951 | GSList **ignore, Error **errp) | |
6952 | { | |
6953 | if (g_slist_find(*ignore, c)) { | |
6954 | return true; | |
6955 | } | |
6956 | *ignore = g_slist_prepend(*ignore, c); | |
6957 | return bdrv_can_set_aio_context(c->bs, ctx, ignore, errp); | |
6958 | } | |
6959 | ||
6960 | /* @ignore will accumulate all visited BdrvChild object. The caller is | |
6961 | * responsible for freeing the list afterwards. */ | |
6962 | bool bdrv_can_set_aio_context(BlockDriverState *bs, AioContext *ctx, | |
6963 | GSList **ignore, Error **errp) | |
6964 | { | |
6965 | BdrvChild *c; | |
6966 | ||
6967 | if (bdrv_get_aio_context(bs) == ctx) { | |
6968 | return true; | |
6969 | } | |
6970 | ||
6971 | QLIST_FOREACH(c, &bs->parents, next_parent) { | |
6972 | if (!bdrv_parent_can_set_aio_context(c, ctx, ignore, errp)) { | |
6973 | return false; | |
6974 | } | |
6975 | } | |
6976 | QLIST_FOREACH(c, &bs->children, next) { | |
6977 | if (!bdrv_child_can_set_aio_context(c, ctx, ignore, errp)) { | |
6978 | return false; | |
6979 | } | |
6980 | } | |
6981 | ||
6982 | return true; | |
6983 | } | |
6984 | ||
6985 | int bdrv_child_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, | |
6986 | BdrvChild *ignore_child, Error **errp) | |
6987 | { | |
6988 | GSList *ignore; | |
6989 | bool ret; | |
6990 | ||
6991 | ignore = ignore_child ? g_slist_prepend(NULL, ignore_child) : NULL; | |
6992 | ret = bdrv_can_set_aio_context(bs, ctx, &ignore, errp); | |
6993 | g_slist_free(ignore); | |
6994 | ||
6995 | if (!ret) { | |
6996 | return -EPERM; | |
6997 | } | |
6998 | ||
53a7d041 KW |
6999 | ignore = ignore_child ? g_slist_prepend(NULL, ignore_child) : NULL; |
7000 | bdrv_set_aio_context_ignore(bs, ctx, &ignore); | |
7001 | g_slist_free(ignore); | |
7002 | ||
5d231849 KW |
7003 | return 0; |
7004 | } | |
7005 | ||
7006 | int bdrv_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, | |
7007 | Error **errp) | |
7008 | { | |
7009 | return bdrv_child_try_set_aio_context(bs, ctx, NULL, errp); | |
7010 | } | |
7011 | ||
33384421 HR |
7012 | void bdrv_add_aio_context_notifier(BlockDriverState *bs, |
7013 | void (*attached_aio_context)(AioContext *new_context, void *opaque), | |
7014 | void (*detach_aio_context)(void *opaque), void *opaque) | |
7015 | { | |
7016 | BdrvAioNotifier *ban = g_new(BdrvAioNotifier, 1); | |
7017 | *ban = (BdrvAioNotifier){ | |
7018 | .attached_aio_context = attached_aio_context, | |
7019 | .detach_aio_context = detach_aio_context, | |
7020 | .opaque = opaque | |
7021 | }; | |
7022 | ||
7023 | QLIST_INSERT_HEAD(&bs->aio_notifiers, ban, list); | |
7024 | } | |
7025 | ||
7026 | void bdrv_remove_aio_context_notifier(BlockDriverState *bs, | |
7027 | void (*attached_aio_context)(AioContext *, | |
7028 | void *), | |
7029 | void (*detach_aio_context)(void *), | |
7030 | void *opaque) | |
7031 | { | |
7032 | BdrvAioNotifier *ban, *ban_next; | |
7033 | ||
7034 | QLIST_FOREACH_SAFE(ban, &bs->aio_notifiers, list, ban_next) { | |
7035 | if (ban->attached_aio_context == attached_aio_context && | |
7036 | ban->detach_aio_context == detach_aio_context && | |
e8a095da SH |
7037 | ban->opaque == opaque && |
7038 | ban->deleted == false) | |
33384421 | 7039 | { |
e8a095da SH |
7040 | if (bs->walking_aio_notifiers) { |
7041 | ban->deleted = true; | |
7042 | } else { | |
7043 | bdrv_do_remove_aio_context_notifier(ban); | |
7044 | } | |
33384421 HR |
7045 | return; |
7046 | } | |
7047 | } | |
7048 | ||
7049 | abort(); | |
7050 | } | |
7051 | ||
77485434 | 7052 | int bdrv_amend_options(BlockDriverState *bs, QemuOpts *opts, |
d1402b50 | 7053 | BlockDriverAmendStatusCB *status_cb, void *cb_opaque, |
a3579bfa | 7054 | bool force, |
d1402b50 | 7055 | Error **errp) |
6f176b48 | 7056 | { |
d470ad42 | 7057 | if (!bs->drv) { |
d1402b50 | 7058 | error_setg(errp, "Node is ejected"); |
d470ad42 HR |
7059 | return -ENOMEDIUM; |
7060 | } | |
c282e1fd | 7061 | if (!bs->drv->bdrv_amend_options) { |
d1402b50 HR |
7062 | error_setg(errp, "Block driver '%s' does not support option amendment", |
7063 | bs->drv->format_name); | |
6f176b48 HR |
7064 | return -ENOTSUP; |
7065 | } | |
a3579bfa ML |
7066 | return bs->drv->bdrv_amend_options(bs, opts, status_cb, |
7067 | cb_opaque, force, errp); | |
6f176b48 | 7068 | } |
f6186f49 | 7069 | |
5d69b5ab HR |
7070 | /* |
7071 | * This function checks whether the given @to_replace is allowed to be | |
7072 | * replaced by a node that always shows the same data as @bs. This is | |
7073 | * used for example to verify whether the mirror job can replace | |
7074 | * @to_replace by the target mirrored from @bs. | |
7075 | * To be replaceable, @bs and @to_replace may either be guaranteed to | |
7076 | * always show the same data (because they are only connected through | |
7077 | * filters), or some driver may allow replacing one of its children | |
7078 | * because it can guarantee that this child's data is not visible at | |
7079 | * all (for example, for dissenting quorum children that have no other | |
7080 | * parents). | |
7081 | */ | |
7082 | bool bdrv_recurse_can_replace(BlockDriverState *bs, | |
7083 | BlockDriverState *to_replace) | |
7084 | { | |
93393e69 HR |
7085 | BlockDriverState *filtered; |
7086 | ||
5d69b5ab HR |
7087 | if (!bs || !bs->drv) { |
7088 | return false; | |
7089 | } | |
7090 | ||
7091 | if (bs == to_replace) { | |
7092 | return true; | |
7093 | } | |
7094 | ||
7095 | /* See what the driver can do */ | |
7096 | if (bs->drv->bdrv_recurse_can_replace) { | |
7097 | return bs->drv->bdrv_recurse_can_replace(bs, to_replace); | |
7098 | } | |
7099 | ||
7100 | /* For filters without an own implementation, we can recurse on our own */ | |
93393e69 HR |
7101 | filtered = bdrv_filter_bs(bs); |
7102 | if (filtered) { | |
7103 | return bdrv_recurse_can_replace(filtered, to_replace); | |
5d69b5ab HR |
7104 | } |
7105 | ||
7106 | /* Safe default */ | |
7107 | return false; | |
7108 | } | |
7109 | ||
810803a8 HR |
7110 | /* |
7111 | * Check whether the given @node_name can be replaced by a node that | |
7112 | * has the same data as @parent_bs. If so, return @node_name's BDS; | |
7113 | * NULL otherwise. | |
7114 | * | |
7115 | * @node_name must be a (recursive) *child of @parent_bs (or this | |
7116 | * function will return NULL). | |
7117 | * | |
7118 | * The result (whether the node can be replaced or not) is only valid | |
7119 | * for as long as no graph or permission changes occur. | |
7120 | */ | |
e12f3784 WC |
7121 | BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, |
7122 | const char *node_name, Error **errp) | |
09158f00 BC |
7123 | { |
7124 | BlockDriverState *to_replace_bs = bdrv_find_node(node_name); | |
5a7e7a0b SH |
7125 | AioContext *aio_context; |
7126 | ||
09158f00 | 7127 | if (!to_replace_bs) { |
785ec4b1 | 7128 | error_setg(errp, "Failed to find node with node-name='%s'", node_name); |
09158f00 BC |
7129 | return NULL; |
7130 | } | |
7131 | ||
5a7e7a0b SH |
7132 | aio_context = bdrv_get_aio_context(to_replace_bs); |
7133 | aio_context_acquire(aio_context); | |
7134 | ||
09158f00 | 7135 | if (bdrv_op_is_blocked(to_replace_bs, BLOCK_OP_TYPE_REPLACE, errp)) { |
5a7e7a0b SH |
7136 | to_replace_bs = NULL; |
7137 | goto out; | |
09158f00 BC |
7138 | } |
7139 | ||
7140 | /* We don't want arbitrary node of the BDS chain to be replaced only the top | |
7141 | * most non filter in order to prevent data corruption. | |
7142 | * Another benefit is that this tests exclude backing files which are | |
7143 | * blocked by the backing blockers. | |
7144 | */ | |
810803a8 HR |
7145 | if (!bdrv_recurse_can_replace(parent_bs, to_replace_bs)) { |
7146 | error_setg(errp, "Cannot replace '%s' by a node mirrored from '%s', " | |
7147 | "because it cannot be guaranteed that doing so would not " | |
7148 | "lead to an abrupt change of visible data", | |
7149 | node_name, parent_bs->node_name); | |
5a7e7a0b SH |
7150 | to_replace_bs = NULL; |
7151 | goto out; | |
09158f00 BC |
7152 | } |
7153 | ||
5a7e7a0b SH |
7154 | out: |
7155 | aio_context_release(aio_context); | |
09158f00 BC |
7156 | return to_replace_bs; |
7157 | } | |
448ad91d | 7158 | |
97e2f021 HR |
7159 | /** |
7160 | * Iterates through the list of runtime option keys that are said to | |
7161 | * be "strong" for a BDS. An option is called "strong" if it changes | |
7162 | * a BDS's data. For example, the null block driver's "size" and | |
7163 | * "read-zeroes" options are strong, but its "latency-ns" option is | |
7164 | * not. | |
7165 | * | |
7166 | * If a key returned by this function ends with a dot, all options | |
7167 | * starting with that prefix are strong. | |
7168 | */ | |
7169 | static const char *const *strong_options(BlockDriverState *bs, | |
7170 | const char *const *curopt) | |
7171 | { | |
7172 | static const char *const global_options[] = { | |
7173 | "driver", "filename", NULL | |
7174 | }; | |
7175 | ||
7176 | if (!curopt) { | |
7177 | return &global_options[0]; | |
7178 | } | |
7179 | ||
7180 | curopt++; | |
7181 | if (curopt == &global_options[ARRAY_SIZE(global_options) - 1] && bs->drv) { | |
7182 | curopt = bs->drv->strong_runtime_opts; | |
7183 | } | |
7184 | ||
7185 | return (curopt && *curopt) ? curopt : NULL; | |
7186 | } | |
7187 | ||
7188 | /** | |
7189 | * Copies all strong runtime options from bs->options to the given | |
7190 | * QDict. The set of strong option keys is determined by invoking | |
7191 | * strong_options(). | |
7192 | * | |
7193 | * Returns true iff any strong option was present in bs->options (and | |
7194 | * thus copied to the target QDict) with the exception of "filename" | |
7195 | * and "driver". The caller is expected to use this value to decide | |
7196 | * whether the existence of strong options prevents the generation of | |
7197 | * a plain filename. | |
7198 | */ | |
7199 | static bool append_strong_runtime_options(QDict *d, BlockDriverState *bs) | |
7200 | { | |
7201 | bool found_any = false; | |
7202 | const char *const *option_name = NULL; | |
7203 | ||
7204 | if (!bs->drv) { | |
7205 | return false; | |
7206 | } | |
7207 | ||
7208 | while ((option_name = strong_options(bs, option_name))) { | |
7209 | bool option_given = false; | |
7210 | ||
7211 | assert(strlen(*option_name) > 0); | |
7212 | if ((*option_name)[strlen(*option_name) - 1] != '.') { | |
7213 | QObject *entry = qdict_get(bs->options, *option_name); | |
7214 | if (!entry) { | |
7215 | continue; | |
7216 | } | |
7217 | ||
7218 | qdict_put_obj(d, *option_name, qobject_ref(entry)); | |
7219 | option_given = true; | |
7220 | } else { | |
7221 | const QDictEntry *entry; | |
7222 | for (entry = qdict_first(bs->options); entry; | |
7223 | entry = qdict_next(bs->options, entry)) | |
7224 | { | |
7225 | if (strstart(qdict_entry_key(entry), *option_name, NULL)) { | |
7226 | qdict_put_obj(d, qdict_entry_key(entry), | |
7227 | qobject_ref(qdict_entry_value(entry))); | |
7228 | option_given = true; | |
7229 | } | |
7230 | } | |
7231 | } | |
7232 | ||
7233 | /* While "driver" and "filename" need to be included in a JSON filename, | |
7234 | * their existence does not prohibit generation of a plain filename. */ | |
7235 | if (!found_any && option_given && | |
7236 | strcmp(*option_name, "driver") && strcmp(*option_name, "filename")) | |
7237 | { | |
7238 | found_any = true; | |
7239 | } | |
7240 | } | |
7241 | ||
62a01a27 HR |
7242 | if (!qdict_haskey(d, "driver")) { |
7243 | /* Drivers created with bdrv_new_open_driver() may not have a | |
7244 | * @driver option. Add it here. */ | |
7245 | qdict_put_str(d, "driver", bs->drv->format_name); | |
7246 | } | |
7247 | ||
97e2f021 HR |
7248 | return found_any; |
7249 | } | |
7250 | ||
90993623 HR |
7251 | /* Note: This function may return false positives; it may return true |
7252 | * even if opening the backing file specified by bs's image header | |
7253 | * would result in exactly bs->backing. */ | |
0b877d09 | 7254 | bool bdrv_backing_overridden(BlockDriverState *bs) |
90993623 HR |
7255 | { |
7256 | if (bs->backing) { | |
7257 | return strcmp(bs->auto_backing_file, | |
7258 | bs->backing->bs->filename); | |
7259 | } else { | |
7260 | /* No backing BDS, so if the image header reports any backing | |
7261 | * file, it must have been suppressed */ | |
7262 | return bs->auto_backing_file[0] != '\0'; | |
7263 | } | |
7264 | } | |
7265 | ||
91af7014 HR |
7266 | /* Updates the following BDS fields: |
7267 | * - exact_filename: A filename which may be used for opening a block device | |
7268 | * which (mostly) equals the given BDS (even without any | |
7269 | * other options; so reading and writing must return the same | |
7270 | * results, but caching etc. may be different) | |
7271 | * - full_open_options: Options which, when given when opening a block device | |
7272 | * (without a filename), result in a BDS (mostly) | |
7273 | * equalling the given one | |
7274 | * - filename: If exact_filename is set, it is copied here. Otherwise, | |
7275 | * full_open_options is converted to a JSON object, prefixed with | |
7276 | * "json:" (for use through the JSON pseudo protocol) and put here. | |
7277 | */ | |
7278 | void bdrv_refresh_filename(BlockDriverState *bs) | |
7279 | { | |
7280 | BlockDriver *drv = bs->drv; | |
e24518e3 | 7281 | BdrvChild *child; |
52f72d6f | 7282 | BlockDriverState *primary_child_bs; |
91af7014 | 7283 | QDict *opts; |
90993623 | 7284 | bool backing_overridden; |
998b3a1e HR |
7285 | bool generate_json_filename; /* Whether our default implementation should |
7286 | fill exact_filename (false) or not (true) */ | |
91af7014 HR |
7287 | |
7288 | if (!drv) { | |
7289 | return; | |
7290 | } | |
7291 | ||
e24518e3 HR |
7292 | /* This BDS's file name may depend on any of its children's file names, so |
7293 | * refresh those first */ | |
7294 | QLIST_FOREACH(child, &bs->children, next) { | |
7295 | bdrv_refresh_filename(child->bs); | |
91af7014 HR |
7296 | } |
7297 | ||
bb808d5f HR |
7298 | if (bs->implicit) { |
7299 | /* For implicit nodes, just copy everything from the single child */ | |
7300 | child = QLIST_FIRST(&bs->children); | |
7301 | assert(QLIST_NEXT(child, next) == NULL); | |
7302 | ||
7303 | pstrcpy(bs->exact_filename, sizeof(bs->exact_filename), | |
7304 | child->bs->exact_filename); | |
7305 | pstrcpy(bs->filename, sizeof(bs->filename), child->bs->filename); | |
7306 | ||
cb895614 | 7307 | qobject_unref(bs->full_open_options); |
bb808d5f HR |
7308 | bs->full_open_options = qobject_ref(child->bs->full_open_options); |
7309 | ||
7310 | return; | |
7311 | } | |
7312 | ||
90993623 HR |
7313 | backing_overridden = bdrv_backing_overridden(bs); |
7314 | ||
7315 | if (bs->open_flags & BDRV_O_NO_IO) { | |
7316 | /* Without I/O, the backing file does not change anything. | |
7317 | * Therefore, in such a case (primarily qemu-img), we can | |
7318 | * pretend the backing file has not been overridden even if | |
7319 | * it technically has been. */ | |
7320 | backing_overridden = false; | |
7321 | } | |
7322 | ||
97e2f021 HR |
7323 | /* Gather the options QDict */ |
7324 | opts = qdict_new(); | |
998b3a1e HR |
7325 | generate_json_filename = append_strong_runtime_options(opts, bs); |
7326 | generate_json_filename |= backing_overridden; | |
97e2f021 HR |
7327 | |
7328 | if (drv->bdrv_gather_child_options) { | |
7329 | /* Some block drivers may not want to present all of their children's | |
7330 | * options, or name them differently from BdrvChild.name */ | |
7331 | drv->bdrv_gather_child_options(bs, opts, backing_overridden); | |
7332 | } else { | |
7333 | QLIST_FOREACH(child, &bs->children, next) { | |
25191e5f | 7334 | if (child == bs->backing && !backing_overridden) { |
97e2f021 HR |
7335 | /* We can skip the backing BDS if it has not been overridden */ |
7336 | continue; | |
7337 | } | |
7338 | ||
7339 | qdict_put(opts, child->name, | |
7340 | qobject_ref(child->bs->full_open_options)); | |
7341 | } | |
7342 | ||
7343 | if (backing_overridden && !bs->backing) { | |
7344 | /* Force no backing file */ | |
7345 | qdict_put_null(opts, "backing"); | |
7346 | } | |
7347 | } | |
7348 | ||
7349 | qobject_unref(bs->full_open_options); | |
7350 | bs->full_open_options = opts; | |
7351 | ||
52f72d6f HR |
7352 | primary_child_bs = bdrv_primary_bs(bs); |
7353 | ||
998b3a1e HR |
7354 | if (drv->bdrv_refresh_filename) { |
7355 | /* Obsolete information is of no use here, so drop the old file name | |
7356 | * information before refreshing it */ | |
7357 | bs->exact_filename[0] = '\0'; | |
7358 | ||
7359 | drv->bdrv_refresh_filename(bs); | |
52f72d6f HR |
7360 | } else if (primary_child_bs) { |
7361 | /* | |
7362 | * Try to reconstruct valid information from the underlying | |
7363 | * file -- this only works for format nodes (filter nodes | |
7364 | * cannot be probed and as such must be selected by the user | |
7365 | * either through an options dict, or through a special | |
7366 | * filename which the filter driver must construct in its | |
7367 | * .bdrv_refresh_filename() implementation). | |
7368 | */ | |
998b3a1e HR |
7369 | |
7370 | bs->exact_filename[0] = '\0'; | |
7371 | ||
fb695c74 HR |
7372 | /* |
7373 | * We can use the underlying file's filename if: | |
7374 | * - it has a filename, | |
52f72d6f | 7375 | * - the current BDS is not a filter, |
fb695c74 HR |
7376 | * - the file is a protocol BDS, and |
7377 | * - opening that file (as this BDS's format) will automatically create | |
7378 | * the BDS tree we have right now, that is: | |
7379 | * - the user did not significantly change this BDS's behavior with | |
7380 | * some explicit (strong) options | |
7381 | * - no non-file child of this BDS has been overridden by the user | |
7382 | * Both of these conditions are represented by generate_json_filename. | |
7383 | */ | |
52f72d6f HR |
7384 | if (primary_child_bs->exact_filename[0] && |
7385 | primary_child_bs->drv->bdrv_file_open && | |
7386 | !drv->is_filter && !generate_json_filename) | |
fb695c74 | 7387 | { |
52f72d6f | 7388 | strcpy(bs->exact_filename, primary_child_bs->exact_filename); |
998b3a1e HR |
7389 | } |
7390 | } | |
7391 | ||
91af7014 HR |
7392 | if (bs->exact_filename[0]) { |
7393 | pstrcpy(bs->filename, sizeof(bs->filename), bs->exact_filename); | |
97e2f021 | 7394 | } else { |
eab3a467 | 7395 | GString *json = qobject_to_json(QOBJECT(bs->full_open_options)); |
5c86bdf1 | 7396 | if (snprintf(bs->filename, sizeof(bs->filename), "json:%s", |
eab3a467 | 7397 | json->str) >= sizeof(bs->filename)) { |
5c86bdf1 EB |
7398 | /* Give user a hint if we truncated things. */ |
7399 | strcpy(bs->filename + sizeof(bs->filename) - 4, "..."); | |
7400 | } | |
eab3a467 | 7401 | g_string_free(json, true); |
91af7014 HR |
7402 | } |
7403 | } | |
e06018ad | 7404 | |
1e89d0f9 HR |
7405 | char *bdrv_dirname(BlockDriverState *bs, Error **errp) |
7406 | { | |
7407 | BlockDriver *drv = bs->drv; | |
52f72d6f | 7408 | BlockDriverState *child_bs; |
1e89d0f9 HR |
7409 | |
7410 | if (!drv) { | |
7411 | error_setg(errp, "Node '%s' is ejected", bs->node_name); | |
7412 | return NULL; | |
7413 | } | |
7414 | ||
7415 | if (drv->bdrv_dirname) { | |
7416 | return drv->bdrv_dirname(bs, errp); | |
7417 | } | |
7418 | ||
52f72d6f HR |
7419 | child_bs = bdrv_primary_bs(bs); |
7420 | if (child_bs) { | |
7421 | return bdrv_dirname(child_bs, errp); | |
1e89d0f9 HR |
7422 | } |
7423 | ||
7424 | bdrv_refresh_filename(bs); | |
7425 | if (bs->exact_filename[0] != '\0') { | |
7426 | return path_combine(bs->exact_filename, ""); | |
7427 | } | |
7428 | ||
7429 | error_setg(errp, "Cannot generate a base directory for %s nodes", | |
7430 | drv->format_name); | |
7431 | return NULL; | |
7432 | } | |
7433 | ||
e06018ad WC |
7434 | /* |
7435 | * Hot add/remove a BDS's child. So the user can take a child offline when | |
7436 | * it is broken and take a new child online | |
7437 | */ | |
7438 | void bdrv_add_child(BlockDriverState *parent_bs, BlockDriverState *child_bs, | |
7439 | Error **errp) | |
7440 | { | |
7441 | ||
7442 | if (!parent_bs->drv || !parent_bs->drv->bdrv_add_child) { | |
7443 | error_setg(errp, "The node %s does not support adding a child", | |
7444 | bdrv_get_device_or_node_name(parent_bs)); | |
7445 | return; | |
7446 | } | |
7447 | ||
7448 | if (!QLIST_EMPTY(&child_bs->parents)) { | |
7449 | error_setg(errp, "The node %s already has a parent", | |
7450 | child_bs->node_name); | |
7451 | return; | |
7452 | } | |
7453 | ||
7454 | parent_bs->drv->bdrv_add_child(parent_bs, child_bs, errp); | |
7455 | } | |
7456 | ||
7457 | void bdrv_del_child(BlockDriverState *parent_bs, BdrvChild *child, Error **errp) | |
7458 | { | |
7459 | BdrvChild *tmp; | |
7460 | ||
7461 | if (!parent_bs->drv || !parent_bs->drv->bdrv_del_child) { | |
7462 | error_setg(errp, "The node %s does not support removing a child", | |
7463 | bdrv_get_device_or_node_name(parent_bs)); | |
7464 | return; | |
7465 | } | |
7466 | ||
7467 | QLIST_FOREACH(tmp, &parent_bs->children, next) { | |
7468 | if (tmp == child) { | |
7469 | break; | |
7470 | } | |
7471 | } | |
7472 | ||
7473 | if (!tmp) { | |
7474 | error_setg(errp, "The node %s does not have a child named %s", | |
7475 | bdrv_get_device_or_node_name(parent_bs), | |
7476 | bdrv_get_device_or_node_name(child->bs)); | |
7477 | return; | |
7478 | } | |
7479 | ||
7480 | parent_bs->drv->bdrv_del_child(parent_bs, child, errp); | |
7481 | } | |
6f7a3b53 HR |
7482 | |
7483 | int bdrv_make_empty(BdrvChild *c, Error **errp) | |
7484 | { | |
7485 | BlockDriver *drv = c->bs->drv; | |
7486 | int ret; | |
7487 | ||
7488 | assert(c->perm & (BLK_PERM_WRITE | BLK_PERM_WRITE_UNCHANGED)); | |
7489 | ||
7490 | if (!drv->bdrv_make_empty) { | |
7491 | error_setg(errp, "%s does not support emptying nodes", | |
7492 | drv->format_name); | |
7493 | return -ENOTSUP; | |
7494 | } | |
7495 | ||
7496 | ret = drv->bdrv_make_empty(c->bs); | |
7497 | if (ret < 0) { | |
7498 | error_setg_errno(errp, -ret, "Failed to empty %s", | |
7499 | c->bs->filename); | |
7500 | return ret; | |
7501 | } | |
7502 | ||
7503 | return 0; | |
7504 | } | |
9a6fc887 HR |
7505 | |
7506 | /* | |
7507 | * Return the child that @bs acts as an overlay for, and from which data may be | |
7508 | * copied in COW or COR operations. Usually this is the backing file. | |
7509 | */ | |
7510 | BdrvChild *bdrv_cow_child(BlockDriverState *bs) | |
7511 | { | |
7512 | if (!bs || !bs->drv) { | |
7513 | return NULL; | |
7514 | } | |
7515 | ||
7516 | if (bs->drv->is_filter) { | |
7517 | return NULL; | |
7518 | } | |
7519 | ||
7520 | if (!bs->backing) { | |
7521 | return NULL; | |
7522 | } | |
7523 | ||
7524 | assert(bs->backing->role & BDRV_CHILD_COW); | |
7525 | return bs->backing; | |
7526 | } | |
7527 | ||
7528 | /* | |
7529 | * If @bs acts as a filter for exactly one of its children, return | |
7530 | * that child. | |
7531 | */ | |
7532 | BdrvChild *bdrv_filter_child(BlockDriverState *bs) | |
7533 | { | |
7534 | BdrvChild *c; | |
7535 | ||
7536 | if (!bs || !bs->drv) { | |
7537 | return NULL; | |
7538 | } | |
7539 | ||
7540 | if (!bs->drv->is_filter) { | |
7541 | return NULL; | |
7542 | } | |
7543 | ||
7544 | /* Only one of @backing or @file may be used */ | |
7545 | assert(!(bs->backing && bs->file)); | |
7546 | ||
7547 | c = bs->backing ?: bs->file; | |
7548 | if (!c) { | |
7549 | return NULL; | |
7550 | } | |
7551 | ||
7552 | assert(c->role & BDRV_CHILD_FILTERED); | |
7553 | return c; | |
7554 | } | |
7555 | ||
7556 | /* | |
7557 | * Return either the result of bdrv_cow_child() or bdrv_filter_child(), | |
7558 | * whichever is non-NULL. | |
7559 | * | |
7560 | * Return NULL if both are NULL. | |
7561 | */ | |
7562 | BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs) | |
7563 | { | |
7564 | BdrvChild *cow_child = bdrv_cow_child(bs); | |
7565 | BdrvChild *filter_child = bdrv_filter_child(bs); | |
7566 | ||
7567 | /* Filter nodes cannot have COW backing files */ | |
7568 | assert(!(cow_child && filter_child)); | |
7569 | ||
7570 | return cow_child ?: filter_child; | |
7571 | } | |
7572 | ||
7573 | /* | |
7574 | * Return the primary child of this node: For filters, that is the | |
7575 | * filtered child. For other nodes, that is usually the child storing | |
7576 | * metadata. | |
7577 | * (A generally more helpful description is that this is (usually) the | |
7578 | * child that has the same filename as @bs.) | |
7579 | * | |
7580 | * Drivers do not necessarily have a primary child; for example quorum | |
7581 | * does not. | |
7582 | */ | |
7583 | BdrvChild *bdrv_primary_child(BlockDriverState *bs) | |
7584 | { | |
7585 | BdrvChild *c, *found = NULL; | |
7586 | ||
7587 | QLIST_FOREACH(c, &bs->children, next) { | |
7588 | if (c->role & BDRV_CHILD_PRIMARY) { | |
7589 | assert(!found); | |
7590 | found = c; | |
7591 | } | |
7592 | } | |
7593 | ||
7594 | return found; | |
7595 | } | |
d38d7eb8 HR |
7596 | |
7597 | static BlockDriverState *bdrv_do_skip_filters(BlockDriverState *bs, | |
7598 | bool stop_on_explicit_filter) | |
7599 | { | |
7600 | BdrvChild *c; | |
7601 | ||
7602 | if (!bs) { | |
7603 | return NULL; | |
7604 | } | |
7605 | ||
7606 | while (!(stop_on_explicit_filter && !bs->implicit)) { | |
7607 | c = bdrv_filter_child(bs); | |
7608 | if (!c) { | |
7609 | /* | |
7610 | * A filter that is embedded in a working block graph must | |
7611 | * have a child. Assert this here so this function does | |
7612 | * not return a filter node that is not expected by the | |
7613 | * caller. | |
7614 | */ | |
7615 | assert(!bs->drv || !bs->drv->is_filter); | |
7616 | break; | |
7617 | } | |
7618 | bs = c->bs; | |
7619 | } | |
7620 | /* | |
7621 | * Note that this treats nodes with bs->drv == NULL as not being | |
7622 | * filters (bs->drv == NULL should be replaced by something else | |
7623 | * anyway). | |
7624 | * The advantage of this behavior is that this function will thus | |
7625 | * always return a non-NULL value (given a non-NULL @bs). | |
7626 | */ | |
7627 | ||
7628 | return bs; | |
7629 | } | |
7630 | ||
7631 | /* | |
7632 | * Return the first BDS that has not been added implicitly or that | |
7633 | * does not have a filtered child down the chain starting from @bs | |
7634 | * (including @bs itself). | |
7635 | */ | |
7636 | BlockDriverState *bdrv_skip_implicit_filters(BlockDriverState *bs) | |
7637 | { | |
7638 | return bdrv_do_skip_filters(bs, true); | |
7639 | } | |
7640 | ||
7641 | /* | |
7642 | * Return the first BDS that does not have a filtered child down the | |
7643 | * chain starting from @bs (including @bs itself). | |
7644 | */ | |
7645 | BlockDriverState *bdrv_skip_filters(BlockDriverState *bs) | |
7646 | { | |
7647 | return bdrv_do_skip_filters(bs, false); | |
7648 | } | |
7649 | ||
7650 | /* | |
7651 | * For a backing chain, return the first non-filter backing image of | |
7652 | * the first non-filter image. | |
7653 | */ | |
7654 | BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs) | |
7655 | { | |
7656 | return bdrv_skip_filters(bdrv_cow_bs(bdrv_skip_filters(bs))); | |
7657 | } |