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block: add flags argument to bdrv_co_write_zeroes tracepoint
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CommitLineData
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 */
3990d09a 24#include "config-host.h"
faf07963 25#include "qemu-common.h"
6d519a5f 26#include "trace.h"
83c9089e 27#include "monitor/monitor.h"
737e150e
PB
28#include "block/block_int.h"
29#include "block/blockjob.h"
1de7afc9 30#include "qemu/module.h"
7b1b5d19 31#include "qapi/qmp/qjson.h"
9c17d615 32#include "sysemu/sysemu.h"
1de7afc9 33#include "qemu/notify.h"
737e150e 34#include "block/coroutine.h"
b2023818 35#include "qmp-commands.h"
1de7afc9 36#include "qemu/timer.h"
fc01f7e7 37
71e72a19 38#ifdef CONFIG_BSD
7674e7bf
FB
39#include <sys/types.h>
40#include <sys/stat.h>
41#include <sys/ioctl.h>
72cf2d4f 42#include <sys/queue.h>
c5e97233 43#ifndef __DragonFly__
7674e7bf
FB
44#include <sys/disk.h>
45#endif
c5e97233 46#endif
7674e7bf 47
49dc768d
AL
48#ifdef _WIN32
49#include <windows.h>
50#endif
51
e4654d2d
FZ
52struct BdrvDirtyBitmap {
53 HBitmap *bitmap;
54 QLIST_ENTRY(BdrvDirtyBitmap) list;
55};
56
1c9805a3
SH
57#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */
58
7d4b4ba5 59static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load);
f141eafe
AL
60static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
61 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
c87c0672 62 BlockDriverCompletionFunc *cb, void *opaque);
f141eafe
AL
63static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
64 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
ce1a14dc 65 BlockDriverCompletionFunc *cb, void *opaque);
f9f05dc5
KW
66static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
67 int64_t sector_num, int nb_sectors,
68 QEMUIOVector *iov);
69static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
70 int64_t sector_num, int nb_sectors,
71 QEMUIOVector *iov);
c5fbe571 72static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs,
470c0504
SH
73 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
74 BdrvRequestFlags flags);
1c9805a3 75static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs,
f08f2dda
SH
76 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
77 BdrvRequestFlags flags);
b2a61371
SH
78static BlockDriverAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
79 int64_t sector_num,
80 QEMUIOVector *qiov,
81 int nb_sectors,
d20d9b7c 82 BdrvRequestFlags flags,
b2a61371
SH
83 BlockDriverCompletionFunc *cb,
84 void *opaque,
8c5873d6 85 bool is_write);
b2a61371 86static void coroutine_fn bdrv_co_do_rw(void *opaque);
621f0589 87static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs,
aa7bfbff 88 int64_t sector_num, int nb_sectors, BdrvRequestFlags flags);
ec530c81 89
1b7bdbc1
SH
90static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
91 QTAILQ_HEAD_INITIALIZER(bdrv_states);
7ee930d0 92
8a22f02a
SH
93static QLIST_HEAD(, BlockDriver) bdrv_drivers =
94 QLIST_HEAD_INITIALIZER(bdrv_drivers);
ea2384d3 95
eb852011
MA
96/* If non-zero, use only whitelisted block drivers */
97static int use_bdrv_whitelist;
98
9e0b22f4
SH
99#ifdef _WIN32
100static int is_windows_drive_prefix(const char *filename)
101{
102 return (((filename[0] >= 'a' && filename[0] <= 'z') ||
103 (filename[0] >= 'A' && filename[0] <= 'Z')) &&
104 filename[1] == ':');
105}
106
107int is_windows_drive(const char *filename)
108{
109 if (is_windows_drive_prefix(filename) &&
110 filename[2] == '\0')
111 return 1;
112 if (strstart(filename, "\\\\.\\", NULL) ||
113 strstart(filename, "//./", NULL))
114 return 1;
115 return 0;
116}
117#endif
118
0563e191 119/* throttling disk I/O limits */
cc0681c4
BC
120void bdrv_set_io_limits(BlockDriverState *bs,
121 ThrottleConfig *cfg)
98f90dba 122{
cc0681c4 123 int i;
98f90dba 124
cc0681c4 125 throttle_config(&bs->throttle_state, cfg);
98f90dba 126
cc0681c4
BC
127 for (i = 0; i < 2; i++) {
128 qemu_co_enter_next(&bs->throttled_reqs[i]);
98f90dba 129 }
cc0681c4
BC
130}
131
132/* this function drain all the throttled IOs */
133static bool bdrv_start_throttled_reqs(BlockDriverState *bs)
134{
135 bool drained = false;
136 bool enabled = bs->io_limits_enabled;
137 int i;
138
139 bs->io_limits_enabled = false;
140
141 for (i = 0; i < 2; i++) {
142 while (qemu_co_enter_next(&bs->throttled_reqs[i])) {
143 drained = true;
144 }
145 }
146
147 bs->io_limits_enabled = enabled;
98f90dba 148
cc0681c4 149 return drained;
98f90dba
ZYW
150}
151
cc0681c4 152void bdrv_io_limits_disable(BlockDriverState *bs)
0563e191 153{
cc0681c4 154 bs->io_limits_enabled = false;
0563e191 155
cc0681c4
BC
156 bdrv_start_throttled_reqs(bs);
157
158 throttle_destroy(&bs->throttle_state);
0563e191
ZYW
159}
160
cc0681c4 161static void bdrv_throttle_read_timer_cb(void *opaque)
0563e191 162{
cc0681c4
BC
163 BlockDriverState *bs = opaque;
164 qemu_co_enter_next(&bs->throttled_reqs[0]);
0563e191
ZYW
165}
166
cc0681c4 167static void bdrv_throttle_write_timer_cb(void *opaque)
0563e191 168{
cc0681c4
BC
169 BlockDriverState *bs = opaque;
170 qemu_co_enter_next(&bs->throttled_reqs[1]);
0563e191
ZYW
171}
172
cc0681c4
BC
173/* should be called before bdrv_set_io_limits if a limit is set */
174void bdrv_io_limits_enable(BlockDriverState *bs)
175{
176 assert(!bs->io_limits_enabled);
177 throttle_init(&bs->throttle_state,
178 QEMU_CLOCK_VIRTUAL,
179 bdrv_throttle_read_timer_cb,
180 bdrv_throttle_write_timer_cb,
181 bs);
182 bs->io_limits_enabled = true;
183}
184
185/* This function makes an IO wait if needed
186 *
187 * @nb_sectors: the number of sectors of the IO
188 * @is_write: is the IO a write
189 */
98f90dba 190static void bdrv_io_limits_intercept(BlockDriverState *bs,
cc0681c4
BC
191 int nb_sectors,
192 bool is_write)
98f90dba 193{
cc0681c4
BC
194 /* does this io must wait */
195 bool must_wait = throttle_schedule_timer(&bs->throttle_state, is_write);
98f90dba 196
cc0681c4
BC
197 /* if must wait or any request of this type throttled queue the IO */
198 if (must_wait ||
199 !qemu_co_queue_empty(&bs->throttled_reqs[is_write])) {
200 qemu_co_queue_wait(&bs->throttled_reqs[is_write]);
98f90dba
ZYW
201 }
202
cc0681c4
BC
203 /* the IO will be executed, do the accounting */
204 throttle_account(&bs->throttle_state,
205 is_write,
206 nb_sectors * BDRV_SECTOR_SIZE);
98f90dba 207
cc0681c4
BC
208 /* if the next request must wait -> do nothing */
209 if (throttle_schedule_timer(&bs->throttle_state, is_write)) {
210 return;
98f90dba
ZYW
211 }
212
cc0681c4
BC
213 /* else queue next request for execution */
214 qemu_co_queue_next(&bs->throttled_reqs[is_write]);
98f90dba
ZYW
215}
216
9e0b22f4
SH
217/* check if the path starts with "<protocol>:" */
218static int path_has_protocol(const char *path)
219{
947995c0
PB
220 const char *p;
221
9e0b22f4
SH
222#ifdef _WIN32
223 if (is_windows_drive(path) ||
224 is_windows_drive_prefix(path)) {
225 return 0;
226 }
947995c0
PB
227 p = path + strcspn(path, ":/\\");
228#else
229 p = path + strcspn(path, ":/");
9e0b22f4
SH
230#endif
231
947995c0 232 return *p == ':';
9e0b22f4
SH
233}
234
83f64091 235int path_is_absolute(const char *path)
3b0d4f61 236{
21664424
FB
237#ifdef _WIN32
238 /* specific case for names like: "\\.\d:" */
f53f4da9 239 if (is_windows_drive(path) || is_windows_drive_prefix(path)) {
21664424 240 return 1;
f53f4da9
PB
241 }
242 return (*path == '/' || *path == '\\');
3b9f94e1 243#else
f53f4da9 244 return (*path == '/');
3b9f94e1 245#endif
3b0d4f61
FB
246}
247
83f64091
FB
248/* if filename is absolute, just copy it to dest. Otherwise, build a
249 path to it by considering it is relative to base_path. URL are
250 supported. */
251void path_combine(char *dest, int dest_size,
252 const char *base_path,
253 const char *filename)
3b0d4f61 254{
83f64091
FB
255 const char *p, *p1;
256 int len;
257
258 if (dest_size <= 0)
259 return;
260 if (path_is_absolute(filename)) {
261 pstrcpy(dest, dest_size, filename);
262 } else {
263 p = strchr(base_path, ':');
264 if (p)
265 p++;
266 else
267 p = base_path;
3b9f94e1
FB
268 p1 = strrchr(base_path, '/');
269#ifdef _WIN32
270 {
271 const char *p2;
272 p2 = strrchr(base_path, '\\');
273 if (!p1 || p2 > p1)
274 p1 = p2;
275 }
276#endif
83f64091
FB
277 if (p1)
278 p1++;
279 else
280 p1 = base_path;
281 if (p1 > p)
282 p = p1;
283 len = p - base_path;
284 if (len > dest_size - 1)
285 len = dest_size - 1;
286 memcpy(dest, base_path, len);
287 dest[len] = '\0';
288 pstrcat(dest, dest_size, filename);
3b0d4f61 289 }
3b0d4f61
FB
290}
291
dc5a1371
PB
292void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz)
293{
294 if (bs->backing_file[0] == '\0' || path_has_protocol(bs->backing_file)) {
295 pstrcpy(dest, sz, bs->backing_file);
296 } else {
297 path_combine(dest, sz, bs->filename, bs->backing_file);
298 }
299}
300
5efa9d5a 301void bdrv_register(BlockDriver *bdrv)
ea2384d3 302{
8c5873d6
SH
303 /* Block drivers without coroutine functions need emulation */
304 if (!bdrv->bdrv_co_readv) {
f9f05dc5
KW
305 bdrv->bdrv_co_readv = bdrv_co_readv_em;
306 bdrv->bdrv_co_writev = bdrv_co_writev_em;
307
f8c35c1d
SH
308 /* bdrv_co_readv_em()/brdv_co_writev_em() work in terms of aio, so if
309 * the block driver lacks aio we need to emulate that too.
310 */
f9f05dc5
KW
311 if (!bdrv->bdrv_aio_readv) {
312 /* add AIO emulation layer */
313 bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
314 bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
f9f05dc5 315 }
83f64091 316 }
b2e12bc6 317
8a22f02a 318 QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list);
ea2384d3 319}
b338082b
FB
320
321/* create a new block device (by default it is empty) */
322BlockDriverState *bdrv_new(const char *device_name)
323{
1b7bdbc1 324 BlockDriverState *bs;
b338082b 325
7267c094 326 bs = g_malloc0(sizeof(BlockDriverState));
e4654d2d 327 QLIST_INIT(&bs->dirty_bitmaps);
b338082b 328 pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
ea2384d3 329 if (device_name[0] != '\0') {
1b7bdbc1 330 QTAILQ_INSERT_TAIL(&bdrv_states, bs, list);
ea2384d3 331 }
28a7282a 332 bdrv_iostatus_disable(bs);
d7d512f6 333 notifier_list_init(&bs->close_notifiers);
d616b224 334 notifier_with_return_list_init(&bs->before_write_notifiers);
cc0681c4
BC
335 qemu_co_queue_init(&bs->throttled_reqs[0]);
336 qemu_co_queue_init(&bs->throttled_reqs[1]);
9fcb0251 337 bs->refcnt = 1;
d7d512f6 338
b338082b
FB
339 return bs;
340}
341
d7d512f6
PB
342void bdrv_add_close_notifier(BlockDriverState *bs, Notifier *notify)
343{
344 notifier_list_add(&bs->close_notifiers, notify);
345}
346
ea2384d3
FB
347BlockDriver *bdrv_find_format(const char *format_name)
348{
349 BlockDriver *drv1;
8a22f02a
SH
350 QLIST_FOREACH(drv1, &bdrv_drivers, list) {
351 if (!strcmp(drv1->format_name, format_name)) {
ea2384d3 352 return drv1;
8a22f02a 353 }
ea2384d3
FB
354 }
355 return NULL;
356}
357
b64ec4e4 358static int bdrv_is_whitelisted(BlockDriver *drv, bool read_only)
eb852011 359{
b64ec4e4
FZ
360 static const char *whitelist_rw[] = {
361 CONFIG_BDRV_RW_WHITELIST
362 };
363 static const char *whitelist_ro[] = {
364 CONFIG_BDRV_RO_WHITELIST
eb852011
MA
365 };
366 const char **p;
367
b64ec4e4 368 if (!whitelist_rw[0] && !whitelist_ro[0]) {
eb852011 369 return 1; /* no whitelist, anything goes */
b64ec4e4 370 }
eb852011 371
b64ec4e4 372 for (p = whitelist_rw; *p; p++) {
eb852011
MA
373 if (!strcmp(drv->format_name, *p)) {
374 return 1;
375 }
376 }
b64ec4e4
FZ
377 if (read_only) {
378 for (p = whitelist_ro; *p; p++) {
379 if (!strcmp(drv->format_name, *p)) {
380 return 1;
381 }
382 }
383 }
eb852011
MA
384 return 0;
385}
386
b64ec4e4
FZ
387BlockDriver *bdrv_find_whitelisted_format(const char *format_name,
388 bool read_only)
eb852011
MA
389{
390 BlockDriver *drv = bdrv_find_format(format_name);
b64ec4e4 391 return drv && bdrv_is_whitelisted(drv, read_only) ? drv : NULL;
eb852011
MA
392}
393
5b7e1542
ZYW
394typedef struct CreateCo {
395 BlockDriver *drv;
396 char *filename;
397 QEMUOptionParameter *options;
398 int ret;
cc84d90f 399 Error *err;
5b7e1542
ZYW
400} CreateCo;
401
402static void coroutine_fn bdrv_create_co_entry(void *opaque)
403{
cc84d90f
HR
404 Error *local_err = NULL;
405 int ret;
406
5b7e1542
ZYW
407 CreateCo *cco = opaque;
408 assert(cco->drv);
409
cc84d90f
HR
410 ret = cco->drv->bdrv_create(cco->filename, cco->options, &local_err);
411 if (error_is_set(&local_err)) {
412 error_propagate(&cco->err, local_err);
413 }
414 cco->ret = ret;
5b7e1542
ZYW
415}
416
0e7e1989 417int bdrv_create(BlockDriver *drv, const char* filename,
cc84d90f 418 QEMUOptionParameter *options, Error **errp)
ea2384d3 419{
5b7e1542
ZYW
420 int ret;
421
422 Coroutine *co;
423 CreateCo cco = {
424 .drv = drv,
425 .filename = g_strdup(filename),
426 .options = options,
427 .ret = NOT_DONE,
cc84d90f 428 .err = NULL,
5b7e1542
ZYW
429 };
430
431 if (!drv->bdrv_create) {
cc84d90f 432 error_setg(errp, "Driver '%s' does not support image creation", drv->format_name);
80168bff
LC
433 ret = -ENOTSUP;
434 goto out;
5b7e1542
ZYW
435 }
436
437 if (qemu_in_coroutine()) {
438 /* Fast-path if already in coroutine context */
439 bdrv_create_co_entry(&cco);
440 } else {
441 co = qemu_coroutine_create(bdrv_create_co_entry);
442 qemu_coroutine_enter(co, &cco);
443 while (cco.ret == NOT_DONE) {
444 qemu_aio_wait();
445 }
446 }
447
448 ret = cco.ret;
cc84d90f
HR
449 if (ret < 0) {
450 if (error_is_set(&cco.err)) {
451 error_propagate(errp, cco.err);
452 } else {
453 error_setg_errno(errp, -ret, "Could not create image");
454 }
455 }
0e7e1989 456
80168bff
LC
457out:
458 g_free(cco.filename);
5b7e1542 459 return ret;
ea2384d3
FB
460}
461
cc84d90f
HR
462int bdrv_create_file(const char* filename, QEMUOptionParameter *options,
463 Error **errp)
84a12e66
CH
464{
465 BlockDriver *drv;
cc84d90f
HR
466 Error *local_err = NULL;
467 int ret;
84a12e66 468
98289620 469 drv = bdrv_find_protocol(filename, true);
84a12e66 470 if (drv == NULL) {
cc84d90f 471 error_setg(errp, "Could not find protocol for file '%s'", filename);
16905d71 472 return -ENOENT;
84a12e66
CH
473 }
474
cc84d90f
HR
475 ret = bdrv_create(drv, filename, options, &local_err);
476 if (error_is_set(&local_err)) {
477 error_propagate(errp, local_err);
478 }
479 return ret;
84a12e66
CH
480}
481
eba25057
JM
482/*
483 * Create a uniquely-named empty temporary file.
484 * Return 0 upon success, otherwise a negative errno value.
485 */
486int get_tmp_filename(char *filename, int size)
d5249393 487{
eba25057 488#ifdef _WIN32
3b9f94e1 489 char temp_dir[MAX_PATH];
eba25057
JM
490 /* GetTempFileName requires that its output buffer (4th param)
491 have length MAX_PATH or greater. */
492 assert(size >= MAX_PATH);
493 return (GetTempPath(MAX_PATH, temp_dir)
494 && GetTempFileName(temp_dir, "qem", 0, filename)
495 ? 0 : -GetLastError());
d5249393 496#else
67b915a5 497 int fd;
7ccfb2eb 498 const char *tmpdir;
0badc1ee
AJ
499 tmpdir = getenv("TMPDIR");
500 if (!tmpdir)
501 tmpdir = "/tmp";
eba25057
JM
502 if (snprintf(filename, size, "%s/vl.XXXXXX", tmpdir) >= size) {
503 return -EOVERFLOW;
504 }
ea2384d3 505 fd = mkstemp(filename);
fe235a06
DH
506 if (fd < 0) {
507 return -errno;
508 }
509 if (close(fd) != 0) {
510 unlink(filename);
eba25057
JM
511 return -errno;
512 }
513 return 0;
d5249393 514#endif
eba25057 515}
fc01f7e7 516
84a12e66
CH
517/*
518 * Detect host devices. By convention, /dev/cdrom[N] is always
519 * recognized as a host CDROM.
520 */
521static BlockDriver *find_hdev_driver(const char *filename)
522{
523 int score_max = 0, score;
524 BlockDriver *drv = NULL, *d;
525
526 QLIST_FOREACH(d, &bdrv_drivers, list) {
527 if (d->bdrv_probe_device) {
528 score = d->bdrv_probe_device(filename);
529 if (score > score_max) {
530 score_max = score;
531 drv = d;
532 }
533 }
534 }
535
536 return drv;
537}
538
98289620
KW
539BlockDriver *bdrv_find_protocol(const char *filename,
540 bool allow_protocol_prefix)
83f64091
FB
541{
542 BlockDriver *drv1;
543 char protocol[128];
1cec71e3 544 int len;
83f64091 545 const char *p;
19cb3738 546
66f82cee
KW
547 /* TODO Drivers without bdrv_file_open must be specified explicitly */
548
39508e7a
CH
549 /*
550 * XXX(hch): we really should not let host device detection
551 * override an explicit protocol specification, but moving this
552 * later breaks access to device names with colons in them.
553 * Thanks to the brain-dead persistent naming schemes on udev-
554 * based Linux systems those actually are quite common.
555 */
556 drv1 = find_hdev_driver(filename);
557 if (drv1) {
558 return drv1;
559 }
560
98289620 561 if (!path_has_protocol(filename) || !allow_protocol_prefix) {
39508e7a 562 return bdrv_find_format("file");
84a12e66 563 }
98289620 564
9e0b22f4
SH
565 p = strchr(filename, ':');
566 assert(p != NULL);
1cec71e3
AL
567 len = p - filename;
568 if (len > sizeof(protocol) - 1)
569 len = sizeof(protocol) - 1;
570 memcpy(protocol, filename, len);
571 protocol[len] = '\0';
8a22f02a 572 QLIST_FOREACH(drv1, &bdrv_drivers, list) {
5fafdf24 573 if (drv1->protocol_name &&
8a22f02a 574 !strcmp(drv1->protocol_name, protocol)) {
83f64091 575 return drv1;
8a22f02a 576 }
83f64091
FB
577 }
578 return NULL;
579}
580
f500a6d3 581static int find_image_format(BlockDriverState *bs, const char *filename,
34b5d2c6 582 BlockDriver **pdrv, Error **errp)
f3a5d3f8 583{
f500a6d3 584 int score, score_max;
f3a5d3f8
CH
585 BlockDriver *drv1, *drv;
586 uint8_t buf[2048];
f500a6d3 587 int ret = 0;
f8ea0b00 588
08a00559 589 /* Return the raw BlockDriver * to scsi-generic devices or empty drives */
8e895599 590 if (bs->sg || !bdrv_is_inserted(bs) || bdrv_getlength(bs) == 0) {
c98ac35d
SW
591 drv = bdrv_find_format("raw");
592 if (!drv) {
34b5d2c6 593 error_setg(errp, "Could not find raw image format");
c98ac35d
SW
594 ret = -ENOENT;
595 }
596 *pdrv = drv;
597 return ret;
1a396859 598 }
f8ea0b00 599
83f64091 600 ret = bdrv_pread(bs, 0, buf, sizeof(buf));
83f64091 601 if (ret < 0) {
34b5d2c6
HR
602 error_setg_errno(errp, -ret, "Could not read image for determining its "
603 "format");
c98ac35d
SW
604 *pdrv = NULL;
605 return ret;
83f64091
FB
606 }
607
ea2384d3 608 score_max = 0;
84a12e66 609 drv = NULL;
8a22f02a 610 QLIST_FOREACH(drv1, &bdrv_drivers, list) {
83f64091
FB
611 if (drv1->bdrv_probe) {
612 score = drv1->bdrv_probe(buf, ret, filename);
613 if (score > score_max) {
614 score_max = score;
615 drv = drv1;
616 }
0849bf08 617 }
fc01f7e7 618 }
c98ac35d 619 if (!drv) {
34b5d2c6
HR
620 error_setg(errp, "Could not determine image format: No compatible "
621 "driver found");
c98ac35d
SW
622 ret = -ENOENT;
623 }
624 *pdrv = drv;
625 return ret;
ea2384d3
FB
626}
627
51762288
SH
628/**
629 * Set the current 'total_sectors' value
630 */
631static int refresh_total_sectors(BlockDriverState *bs, int64_t hint)
632{
633 BlockDriver *drv = bs->drv;
634
396759ad
NB
635 /* Do not attempt drv->bdrv_getlength() on scsi-generic devices */
636 if (bs->sg)
637 return 0;
638
51762288
SH
639 /* query actual device if possible, otherwise just trust the hint */
640 if (drv->bdrv_getlength) {
641 int64_t length = drv->bdrv_getlength(bs);
642 if (length < 0) {
643 return length;
644 }
7e382003 645 hint = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE);
51762288
SH
646 }
647
648 bs->total_sectors = hint;
649 return 0;
650}
651
9e8f1835
PB
652/**
653 * Set open flags for a given discard mode
654 *
655 * Return 0 on success, -1 if the discard mode was invalid.
656 */
657int bdrv_parse_discard_flags(const char *mode, int *flags)
658{
659 *flags &= ~BDRV_O_UNMAP;
660
661 if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) {
662 /* do nothing */
663 } else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) {
664 *flags |= BDRV_O_UNMAP;
665 } else {
666 return -1;
667 }
668
669 return 0;
670}
671
c3993cdc
SH
672/**
673 * Set open flags for a given cache mode
674 *
675 * Return 0 on success, -1 if the cache mode was invalid.
676 */
677int bdrv_parse_cache_flags(const char *mode, int *flags)
678{
679 *flags &= ~BDRV_O_CACHE_MASK;
680
681 if (!strcmp(mode, "off") || !strcmp(mode, "none")) {
682 *flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB;
92196b2f
SH
683 } else if (!strcmp(mode, "directsync")) {
684 *flags |= BDRV_O_NOCACHE;
c3993cdc
SH
685 } else if (!strcmp(mode, "writeback")) {
686 *flags |= BDRV_O_CACHE_WB;
687 } else if (!strcmp(mode, "unsafe")) {
688 *flags |= BDRV_O_CACHE_WB;
689 *flags |= BDRV_O_NO_FLUSH;
690 } else if (!strcmp(mode, "writethrough")) {
691 /* this is the default */
692 } else {
693 return -1;
694 }
695
696 return 0;
697}
698
53fec9d3
SH
699/**
700 * The copy-on-read flag is actually a reference count so multiple users may
701 * use the feature without worrying about clobbering its previous state.
702 * Copy-on-read stays enabled until all users have called to disable it.
703 */
704void bdrv_enable_copy_on_read(BlockDriverState *bs)
705{
706 bs->copy_on_read++;
707}
708
709void bdrv_disable_copy_on_read(BlockDriverState *bs)
710{
711 assert(bs->copy_on_read > 0);
712 bs->copy_on_read--;
713}
714
7b272452
KW
715static int bdrv_open_flags(BlockDriverState *bs, int flags)
716{
717 int open_flags = flags | BDRV_O_CACHE_WB;
718
719 /*
720 * Clear flags that are internal to the block layer before opening the
721 * image.
722 */
723 open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
724
725 /*
726 * Snapshots should be writable.
727 */
728 if (bs->is_temporary) {
729 open_flags |= BDRV_O_RDWR;
730 }
731
732 return open_flags;
733}
734
57915332
KW
735/*
736 * Common part for opening disk images and files
b6ad491a
KW
737 *
738 * Removes all processed options from *options.
57915332 739 */
f500a6d3 740static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
34b5d2c6 741 QDict *options, int flags, BlockDriver *drv, Error **errp)
57915332
KW
742{
743 int ret, open_flags;
035fccdf 744 const char *filename;
34b5d2c6 745 Error *local_err = NULL;
57915332
KW
746
747 assert(drv != NULL);
6405875c 748 assert(bs->file == NULL);
707ff828 749 assert(options != NULL && bs->options != options);
57915332 750
45673671
KW
751 if (file != NULL) {
752 filename = file->filename;
753 } else {
754 filename = qdict_get_try_str(options, "filename");
755 }
756
757 trace_bdrv_open_common(bs, filename ?: "", flags, drv->format_name);
28dcee10 758
5d186eb0
KW
759 /* bdrv_open() with directly using a protocol as drv. This layer is already
760 * opened, so assign it to bs (while file becomes a closed BlockDriverState)
761 * and return immediately. */
762 if (file != NULL && drv->bdrv_file_open) {
763 bdrv_swap(file, bs);
764 return 0;
765 }
766
57915332 767 bs->open_flags = flags;
57915332 768 bs->buffer_alignment = 512;
0d51b4de 769 bs->zero_beyond_eof = true;
b64ec4e4
FZ
770 open_flags = bdrv_open_flags(bs, flags);
771 bs->read_only = !(open_flags & BDRV_O_RDWR);
772
773 if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) {
8f94a6e4
KW
774 error_setg(errp,
775 !bs->read_only && bdrv_is_whitelisted(drv, true)
776 ? "Driver '%s' can only be used for read-only devices"
777 : "Driver '%s' is not whitelisted",
778 drv->format_name);
b64ec4e4
FZ
779 return -ENOTSUP;
780 }
57915332 781
53fec9d3 782 assert(bs->copy_on_read == 0); /* bdrv_new() and bdrv_close() make it so */
0ebd24e0
KW
783 if (flags & BDRV_O_COPY_ON_READ) {
784 if (!bs->read_only) {
785 bdrv_enable_copy_on_read(bs);
786 } else {
787 error_setg(errp, "Can't use copy-on-read on read-only device");
788 return -EINVAL;
789 }
53fec9d3
SH
790 }
791
c2ad1b0c
KW
792 if (filename != NULL) {
793 pstrcpy(bs->filename, sizeof(bs->filename), filename);
794 } else {
795 bs->filename[0] = '\0';
796 }
57915332 797
57915332 798 bs->drv = drv;
7267c094 799 bs->opaque = g_malloc0(drv->instance_size);
57915332 800
03f541bd 801 bs->enable_write_cache = !!(flags & BDRV_O_CACHE_WB);
e7c63796 802
66f82cee
KW
803 /* Open the image, either directly or using a protocol */
804 if (drv->bdrv_file_open) {
5d186eb0 805 assert(file == NULL);
030be321 806 assert(!drv->bdrv_needs_filename || filename != NULL);
34b5d2c6 807 ret = drv->bdrv_file_open(bs, options, open_flags, &local_err);
f500a6d3 808 } else {
2af5ef70 809 if (file == NULL) {
34b5d2c6
HR
810 error_setg(errp, "Can't use '%s' as a block driver for the "
811 "protocol level", drv->format_name);
2af5ef70
KW
812 ret = -EINVAL;
813 goto free_and_fail;
814 }
f500a6d3 815 bs->file = file;
34b5d2c6 816 ret = drv->bdrv_open(bs, options, open_flags, &local_err);
66f82cee
KW
817 }
818
57915332 819 if (ret < 0) {
34b5d2c6
HR
820 if (error_is_set(&local_err)) {
821 error_propagate(errp, local_err);
2fa9aa59
DH
822 } else if (bs->filename[0]) {
823 error_setg_errno(errp, -ret, "Could not open '%s'", bs->filename);
34b5d2c6
HR
824 } else {
825 error_setg_errno(errp, -ret, "Could not open image");
826 }
57915332
KW
827 goto free_and_fail;
828 }
829
51762288
SH
830 ret = refresh_total_sectors(bs, bs->total_sectors);
831 if (ret < 0) {
34b5d2c6 832 error_setg_errno(errp, -ret, "Could not refresh total sector count");
51762288 833 goto free_and_fail;
57915332 834 }
51762288 835
57915332
KW
836#ifndef _WIN32
837 if (bs->is_temporary) {
d4cea8df
DH
838 assert(bs->filename[0] != '\0');
839 unlink(bs->filename);
57915332
KW
840 }
841#endif
842 return 0;
843
844free_and_fail:
f500a6d3 845 bs->file = NULL;
7267c094 846 g_free(bs->opaque);
57915332
KW
847 bs->opaque = NULL;
848 bs->drv = NULL;
849 return ret;
850}
851
b6ce07aa
KW
852/*
853 * Opens a file using a protocol (file, host_device, nbd, ...)
787e4a85
KW
854 *
855 * options is a QDict of options to pass to the block drivers, or NULL for an
856 * empty set of options. The reference to the QDict belongs to the block layer
857 * after the call (even on failure), so if the caller intends to reuse the
858 * dictionary, it needs to use QINCREF() before calling bdrv_file_open.
b6ce07aa 859 */
787e4a85 860int bdrv_file_open(BlockDriverState **pbs, const char *filename,
34b5d2c6 861 QDict *options, int flags, Error **errp)
ea2384d3 862{
83f64091 863 BlockDriverState *bs;
6db95603 864 BlockDriver *drv;
c2ad1b0c 865 const char *drvname;
98289620 866 bool allow_protocol_prefix = false;
34b5d2c6 867 Error *local_err = NULL;
83f64091
FB
868 int ret;
869
707ff828
KW
870 /* NULL means an empty set of options */
871 if (options == NULL) {
872 options = qdict_new();
873 }
874
83f64091 875 bs = bdrv_new("");
707ff828
KW
876 bs->options = options;
877 options = qdict_clone_shallow(options);
878
035fccdf
KW
879 /* Fetch the file name from the options QDict if necessary */
880 if (!filename) {
881 filename = qdict_get_try_str(options, "filename");
882 } else if (filename && !qdict_haskey(options, "filename")) {
883 qdict_put(options, "filename", qstring_from_str(filename));
98289620 884 allow_protocol_prefix = true;
035fccdf 885 } else {
34b5d2c6
HR
886 error_setg(errp, "Can't specify 'file' and 'filename' options at the "
887 "same time");
035fccdf
KW
888 ret = -EINVAL;
889 goto fail;
890 }
891
c2ad1b0c
KW
892 /* Find the right block driver */
893 drvname = qdict_get_try_str(options, "driver");
894 if (drvname) {
8f94a6e4 895 drv = bdrv_find_format(drvname);
34b5d2c6
HR
896 if (!drv) {
897 error_setg(errp, "Unknown driver '%s'", drvname);
898 }
c2ad1b0c
KW
899 qdict_del(options, "driver");
900 } else if (filename) {
98289620
KW
901 drv = bdrv_find_protocol(filename, allow_protocol_prefix);
902 if (!drv) {
34b5d2c6 903 error_setg(errp, "Unknown protocol");
98289620 904 }
c2ad1b0c 905 } else {
34b5d2c6 906 error_setg(errp, "Must specify either driver or file");
c2ad1b0c
KW
907 drv = NULL;
908 }
909
910 if (!drv) {
34b5d2c6 911 /* errp has been set already */
c2ad1b0c
KW
912 ret = -ENOENT;
913 goto fail;
914 }
915
916 /* Parse the filename and open it */
917 if (drv->bdrv_parse_filename && filename) {
6963a30d
KW
918 drv->bdrv_parse_filename(filename, options, &local_err);
919 if (error_is_set(&local_err)) {
34b5d2c6 920 error_propagate(errp, local_err);
6963a30d
KW
921 ret = -EINVAL;
922 goto fail;
923 }
56d1b4d2 924 qdict_del(options, "filename");
030be321 925 } else if (drv->bdrv_needs_filename && !filename) {
34b5d2c6
HR
926 error_setg(errp, "The '%s' block driver requires a file name",
927 drv->format_name);
c2ad1b0c
KW
928 ret = -EINVAL;
929 goto fail;
6963a30d
KW
930 }
931
34b5d2c6 932 ret = bdrv_open_common(bs, NULL, options, flags, drv, &local_err);
83f64091 933 if (ret < 0) {
34b5d2c6 934 error_propagate(errp, local_err);
707ff828
KW
935 goto fail;
936 }
937
938 /* Check if any unknown options were used */
939 if (qdict_size(options) != 0) {
940 const QDictEntry *entry = qdict_first(options);
34b5d2c6
HR
941 error_setg(errp, "Block protocol '%s' doesn't support the option '%s'",
942 drv->format_name, entry->key);
707ff828
KW
943 ret = -EINVAL;
944 goto fail;
3b0d4f61 945 }
707ff828
KW
946 QDECREF(options);
947
71d0770c 948 bs->growable = 1;
83f64091
FB
949 *pbs = bs;
950 return 0;
707ff828
KW
951
952fail:
953 QDECREF(options);
954 if (!bs->drv) {
955 QDECREF(bs->options);
956 }
4f6fd349 957 bdrv_unref(bs);
707ff828 958 return ret;
83f64091
FB
959}
960
31ca6d07
KW
961/*
962 * Opens the backing file for a BlockDriverState if not yet open
963 *
964 * options is a QDict of options to pass to the block drivers, or NULL for an
965 * empty set of options. The reference to the QDict is transferred to this
966 * function (even on failure), so if the caller intends to reuse the dictionary,
967 * it needs to use QINCREF() before calling bdrv_file_open.
968 */
34b5d2c6 969int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp)
9156df12
PB
970{
971 char backing_filename[PATH_MAX];
972 int back_flags, ret;
973 BlockDriver *back_drv = NULL;
34b5d2c6 974 Error *local_err = NULL;
9156df12
PB
975
976 if (bs->backing_hd != NULL) {
31ca6d07 977 QDECREF(options);
9156df12
PB
978 return 0;
979 }
980
31ca6d07
KW
981 /* NULL means an empty set of options */
982 if (options == NULL) {
983 options = qdict_new();
984 }
985
9156df12 986 bs->open_flags &= ~BDRV_O_NO_BACKING;
1cb6f506
KW
987 if (qdict_haskey(options, "file.filename")) {
988 backing_filename[0] = '\0';
989 } else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) {
31ca6d07 990 QDECREF(options);
9156df12 991 return 0;
dbecebdd
FZ
992 } else {
993 bdrv_get_full_backing_filename(bs, backing_filename,
994 sizeof(backing_filename));
9156df12
PB
995 }
996
997 bs->backing_hd = bdrv_new("");
9156df12
PB
998
999 if (bs->backing_format[0] != '\0') {
1000 back_drv = bdrv_find_format(bs->backing_format);
1001 }
1002
1003 /* backing files always opened read-only */
87a5debd
TL
1004 back_flags = bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT |
1005 BDRV_O_COPY_ON_READ);
9156df12 1006
31ca6d07
KW
1007 ret = bdrv_open(bs->backing_hd,
1008 *backing_filename ? backing_filename : NULL, options,
34b5d2c6 1009 back_flags, back_drv, &local_err);
9156df12 1010 if (ret < 0) {
4f6fd349 1011 bdrv_unref(bs->backing_hd);
9156df12
PB
1012 bs->backing_hd = NULL;
1013 bs->open_flags |= BDRV_O_NO_BACKING;
b04b6b6e
FZ
1014 error_setg(errp, "Could not open backing file: %s",
1015 error_get_pretty(local_err));
1016 error_free(local_err);
9156df12
PB
1017 return ret;
1018 }
61ed2684
HR
1019 pstrcpy(bs->backing_file, sizeof(bs->backing_file),
1020 bs->backing_hd->file->filename);
9156df12
PB
1021 return 0;
1022}
1023
b6ce07aa
KW
1024/*
1025 * Opens a disk image (raw, qcow2, vmdk, ...)
de9c0cec
KW
1026 *
1027 * options is a QDict of options to pass to the block drivers, or NULL for an
1028 * empty set of options. The reference to the QDict belongs to the block layer
1029 * after the call (even on failure), so if the caller intends to reuse the
1030 * dictionary, it needs to use QINCREF() before calling bdrv_open.
b6ce07aa 1031 */
de9c0cec 1032int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options,
34b5d2c6 1033 int flags, BlockDriver *drv, Error **errp)
ea2384d3 1034{
b6ce07aa 1035 int ret;
89c9bc3d
SW
1036 /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */
1037 char tmp_filename[PATH_MAX + 1];
f500a6d3 1038 BlockDriverState *file = NULL;
707ff828 1039 QDict *file_options = NULL;
74fe54f2 1040 const char *drvname;
34b5d2c6 1041 Error *local_err = NULL;
712e7874 1042
de9c0cec
KW
1043 /* NULL means an empty set of options */
1044 if (options == NULL) {
1045 options = qdict_new();
1046 }
1047
1048 bs->options = options;
b6ad491a 1049 options = qdict_clone_shallow(options);
de9c0cec
KW
1050
1051 /* For snapshot=on, create a temporary qcow2 overlay */
83f64091 1052 if (flags & BDRV_O_SNAPSHOT) {
ea2384d3
FB
1053 BlockDriverState *bs1;
1054 int64_t total_size;
91a073a9 1055 BlockDriver *bdrv_qcow2;
08b392e1 1056 QEMUOptionParameter *create_options;
9fd3171a 1057 QDict *snapshot_options;
c2ad1b0c 1058
ea2384d3
FB
1059 /* if snapshot, we create a temporary backing file and open it
1060 instead of opening 'filename' directly */
33e3963e 1061
9fd3171a 1062 /* Get the required size from the image */
ea2384d3 1063 bs1 = bdrv_new("");
9fd3171a 1064 QINCREF(options);
c9fbb99d
KW
1065 ret = bdrv_open(bs1, filename, options, BDRV_O_NO_BACKING,
1066 drv, &local_err);
51d7c00c 1067 if (ret < 0) {
4f6fd349 1068 bdrv_unref(bs1);
de9c0cec 1069 goto fail;
ea2384d3 1070 }
3e82990b 1071 total_size = bdrv_getlength(bs1) & BDRV_SECTOR_MASK;
7c96d46e 1072
4f6fd349 1073 bdrv_unref(bs1);
3b46e624 1074
9fd3171a 1075 /* Create the temporary image */
eba25057
JM
1076 ret = get_tmp_filename(tmp_filename, sizeof(tmp_filename));
1077 if (ret < 0) {
34b5d2c6 1078 error_setg_errno(errp, -ret, "Could not get temporary filename");
de9c0cec 1079 goto fail;
eba25057 1080 }
7c96d46e 1081
91a073a9 1082 bdrv_qcow2 = bdrv_find_format("qcow2");
08b392e1
KW
1083 create_options = parse_option_parameters("", bdrv_qcow2->create_options,
1084 NULL);
91a073a9 1085
08b392e1 1086 set_option_parameter_int(create_options, BLOCK_OPT_SIZE, total_size);
91a073a9 1087
cc84d90f 1088 ret = bdrv_create(bdrv_qcow2, tmp_filename, create_options, &local_err);
08b392e1 1089 free_option_parameters(create_options);
51d7c00c 1090 if (ret < 0) {
34b5d2c6 1091 error_setg_errno(errp, -ret, "Could not create temporary overlay "
cc84d90f
HR
1092 "'%s': %s", tmp_filename,
1093 error_get_pretty(local_err));
1094 error_free(local_err);
1095 local_err = NULL;
de9c0cec 1096 goto fail;
ea2384d3 1097 }
91a073a9 1098
9fd3171a
KW
1099 /* Prepare a new options QDict for the temporary file, where user
1100 * options refer to the backing file */
1101 if (filename) {
1102 qdict_put(options, "file.filename", qstring_from_str(filename));
1103 }
1104 if (drv) {
1105 qdict_put(options, "driver", qstring_from_str(drv->format_name));
1106 }
1107
1108 snapshot_options = qdict_new();
1109 qdict_put(snapshot_options, "backing", options);
1110 qdict_flatten(snapshot_options);
1111
1112 bs->options = snapshot_options;
1113 options = qdict_clone_shallow(bs->options);
1114
ea2384d3 1115 filename = tmp_filename;
91a073a9 1116 drv = bdrv_qcow2;
ea2384d3
FB
1117 bs->is_temporary = 1;
1118 }
712e7874 1119
f500a6d3
KW
1120 /* Open image file without format layer */
1121 if (flags & BDRV_O_RDWR) {
1122 flags |= BDRV_O_ALLOW_RDWR;
1123 }
1124
5726d872 1125 qdict_extract_subqdict(options, &file_options, "file.");
707ff828
KW
1126
1127 ret = bdrv_file_open(&file, filename, file_options,
34b5d2c6 1128 bdrv_open_flags(bs, flags | BDRV_O_UNMAP), &local_err);
f500a6d3 1129 if (ret < 0) {
de9c0cec 1130 goto fail;
f500a6d3
KW
1131 }
1132
b6ce07aa 1133 /* Find the right image format driver */
74fe54f2
KW
1134 drvname = qdict_get_try_str(options, "driver");
1135 if (drvname) {
8f94a6e4 1136 drv = bdrv_find_format(drvname);
74fe54f2 1137 qdict_del(options, "driver");
06d22aa3
KW
1138 if (!drv) {
1139 error_setg(errp, "Invalid driver: '%s'", drvname);
1140 ret = -EINVAL;
1141 goto unlink_and_fail;
1142 }
74fe54f2
KW
1143 }
1144
6db95603 1145 if (!drv) {
34b5d2c6 1146 ret = find_image_format(file, filename, &drv, &local_err);
51d7c00c 1147 }
6987307c 1148
51d7c00c 1149 if (!drv) {
51d7c00c 1150 goto unlink_and_fail;
ea2384d3 1151 }
b6ce07aa
KW
1152
1153 /* Open the image */
34b5d2c6 1154 ret = bdrv_open_common(bs, file, options, flags, drv, &local_err);
b6ce07aa 1155 if (ret < 0) {
6987307c
CH
1156 goto unlink_and_fail;
1157 }
1158
f500a6d3 1159 if (bs->file != file) {
4f6fd349 1160 bdrv_unref(file);
f500a6d3
KW
1161 file = NULL;
1162 }
1163
b6ce07aa 1164 /* If there is a backing file, use it */
9156df12 1165 if ((flags & BDRV_O_NO_BACKING) == 0) {
31ca6d07
KW
1166 QDict *backing_options;
1167
5726d872 1168 qdict_extract_subqdict(options, &backing_options, "backing.");
34b5d2c6 1169 ret = bdrv_open_backing_file(bs, backing_options, &local_err);
b6ce07aa 1170 if (ret < 0) {
b6ad491a 1171 goto close_and_fail;
b6ce07aa 1172 }
b6ce07aa
KW
1173 }
1174
b6ad491a
KW
1175 /* Check if any unknown options were used */
1176 if (qdict_size(options) != 0) {
1177 const QDictEntry *entry = qdict_first(options);
34b5d2c6
HR
1178 error_setg(errp, "Block format '%s' used by device '%s' doesn't "
1179 "support the option '%s'", drv->format_name, bs->device_name,
1180 entry->key);
b6ad491a
KW
1181
1182 ret = -EINVAL;
1183 goto close_and_fail;
1184 }
1185 QDECREF(options);
1186
b6ce07aa 1187 if (!bdrv_key_required(bs)) {
7d4b4ba5 1188 bdrv_dev_change_media_cb(bs, true);
b6ce07aa
KW
1189 }
1190
1191 return 0;
1192
1193unlink_and_fail:
f500a6d3 1194 if (file != NULL) {
4f6fd349 1195 bdrv_unref(file);
f500a6d3 1196 }
b6ce07aa
KW
1197 if (bs->is_temporary) {
1198 unlink(filename);
1199 }
de9c0cec
KW
1200fail:
1201 QDECREF(bs->options);
b6ad491a 1202 QDECREF(options);
de9c0cec 1203 bs->options = NULL;
34b5d2c6
HR
1204 if (error_is_set(&local_err)) {
1205 error_propagate(errp, local_err);
1206 }
b6ad491a 1207 return ret;
de9c0cec 1208
b6ad491a
KW
1209close_and_fail:
1210 bdrv_close(bs);
1211 QDECREF(options);
34b5d2c6
HR
1212 if (error_is_set(&local_err)) {
1213 error_propagate(errp, local_err);
1214 }
b6ce07aa
KW
1215 return ret;
1216}
1217
e971aa12
JC
1218typedef struct BlockReopenQueueEntry {
1219 bool prepared;
1220 BDRVReopenState state;
1221 QSIMPLEQ_ENTRY(BlockReopenQueueEntry) entry;
1222} BlockReopenQueueEntry;
1223
1224/*
1225 * Adds a BlockDriverState to a simple queue for an atomic, transactional
1226 * reopen of multiple devices.
1227 *
1228 * bs_queue can either be an existing BlockReopenQueue that has had QSIMPLE_INIT
1229 * already performed, or alternatively may be NULL a new BlockReopenQueue will
1230 * be created and initialized. This newly created BlockReopenQueue should be
1231 * passed back in for subsequent calls that are intended to be of the same
1232 * atomic 'set'.
1233 *
1234 * bs is the BlockDriverState to add to the reopen queue.
1235 *
1236 * flags contains the open flags for the associated bs
1237 *
1238 * returns a pointer to bs_queue, which is either the newly allocated
1239 * bs_queue, or the existing bs_queue being used.
1240 *
1241 */
1242BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
1243 BlockDriverState *bs, int flags)
1244{
1245 assert(bs != NULL);
1246
1247 BlockReopenQueueEntry *bs_entry;
1248 if (bs_queue == NULL) {
1249 bs_queue = g_new0(BlockReopenQueue, 1);
1250 QSIMPLEQ_INIT(bs_queue);
1251 }
1252
1253 if (bs->file) {
1254 bdrv_reopen_queue(bs_queue, bs->file, flags);
1255 }
1256
1257 bs_entry = g_new0(BlockReopenQueueEntry, 1);
1258 QSIMPLEQ_INSERT_TAIL(bs_queue, bs_entry, entry);
1259
1260 bs_entry->state.bs = bs;
1261 bs_entry->state.flags = flags;
1262
1263 return bs_queue;
1264}
1265
1266/*
1267 * Reopen multiple BlockDriverStates atomically & transactionally.
1268 *
1269 * The queue passed in (bs_queue) must have been built up previous
1270 * via bdrv_reopen_queue().
1271 *
1272 * Reopens all BDS specified in the queue, with the appropriate
1273 * flags. All devices are prepared for reopen, and failure of any
1274 * device will cause all device changes to be abandonded, and intermediate
1275 * data cleaned up.
1276 *
1277 * If all devices prepare successfully, then the changes are committed
1278 * to all devices.
1279 *
1280 */
1281int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp)
1282{
1283 int ret = -1;
1284 BlockReopenQueueEntry *bs_entry, *next;
1285 Error *local_err = NULL;
1286
1287 assert(bs_queue != NULL);
1288
1289 bdrv_drain_all();
1290
1291 QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
1292 if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, &local_err)) {
1293 error_propagate(errp, local_err);
1294 goto cleanup;
1295 }
1296 bs_entry->prepared = true;
1297 }
1298
1299 /* If we reach this point, we have success and just need to apply the
1300 * changes
1301 */
1302 QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
1303 bdrv_reopen_commit(&bs_entry->state);
1304 }
1305
1306 ret = 0;
1307
1308cleanup:
1309 QSIMPLEQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) {
1310 if (ret && bs_entry->prepared) {
1311 bdrv_reopen_abort(&bs_entry->state);
1312 }
1313 g_free(bs_entry);
1314 }
1315 g_free(bs_queue);
1316 return ret;
1317}
1318
1319
1320/* Reopen a single BlockDriverState with the specified flags. */
1321int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp)
1322{
1323 int ret = -1;
1324 Error *local_err = NULL;
1325 BlockReopenQueue *queue = bdrv_reopen_queue(NULL, bs, bdrv_flags);
1326
1327 ret = bdrv_reopen_multiple(queue, &local_err);
1328 if (local_err != NULL) {
1329 error_propagate(errp, local_err);
1330 }
1331 return ret;
1332}
1333
1334
1335/*
1336 * Prepares a BlockDriverState for reopen. All changes are staged in the
1337 * 'opaque' field of the BDRVReopenState, which is used and allocated by
1338 * the block driver layer .bdrv_reopen_prepare()
1339 *
1340 * bs is the BlockDriverState to reopen
1341 * flags are the new open flags
1342 * queue is the reopen queue
1343 *
1344 * Returns 0 on success, non-zero on error. On error errp will be set
1345 * as well.
1346 *
1347 * On failure, bdrv_reopen_abort() will be called to clean up any data.
1348 * It is the responsibility of the caller to then call the abort() or
1349 * commit() for any other BDS that have been left in a prepare() state
1350 *
1351 */
1352int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
1353 Error **errp)
1354{
1355 int ret = -1;
1356 Error *local_err = NULL;
1357 BlockDriver *drv;
1358
1359 assert(reopen_state != NULL);
1360 assert(reopen_state->bs->drv != NULL);
1361 drv = reopen_state->bs->drv;
1362
1363 /* if we are to stay read-only, do not allow permission change
1364 * to r/w */
1365 if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) &&
1366 reopen_state->flags & BDRV_O_RDWR) {
1367 error_set(errp, QERR_DEVICE_IS_READ_ONLY,
1368 reopen_state->bs->device_name);
1369 goto error;
1370 }
1371
1372
1373 ret = bdrv_flush(reopen_state->bs);
1374 if (ret) {
1375 error_set(errp, ERROR_CLASS_GENERIC_ERROR, "Error (%s) flushing drive",
1376 strerror(-ret));
1377 goto error;
1378 }
1379
1380 if (drv->bdrv_reopen_prepare) {
1381 ret = drv->bdrv_reopen_prepare(reopen_state, queue, &local_err);
1382 if (ret) {
1383 if (local_err != NULL) {
1384 error_propagate(errp, local_err);
1385 } else {
d8b6895f
LC
1386 error_setg(errp, "failed while preparing to reopen image '%s'",
1387 reopen_state->bs->filename);
e971aa12
JC
1388 }
1389 goto error;
1390 }
1391 } else {
1392 /* It is currently mandatory to have a bdrv_reopen_prepare()
1393 * handler for each supported drv. */
1394 error_set(errp, QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
1395 drv->format_name, reopen_state->bs->device_name,
1396 "reopening of file");
1397 ret = -1;
1398 goto error;
1399 }
1400
1401 ret = 0;
1402
1403error:
1404 return ret;
1405}
1406
1407/*
1408 * Takes the staged changes for the reopen from bdrv_reopen_prepare(), and
1409 * makes them final by swapping the staging BlockDriverState contents into
1410 * the active BlockDriverState contents.
1411 */
1412void bdrv_reopen_commit(BDRVReopenState *reopen_state)
1413{
1414 BlockDriver *drv;
1415
1416 assert(reopen_state != NULL);
1417 drv = reopen_state->bs->drv;
1418 assert(drv != NULL);
1419
1420 /* If there are any driver level actions to take */
1421 if (drv->bdrv_reopen_commit) {
1422 drv->bdrv_reopen_commit(reopen_state);
1423 }
1424
1425 /* set BDS specific flags now */
1426 reopen_state->bs->open_flags = reopen_state->flags;
1427 reopen_state->bs->enable_write_cache = !!(reopen_state->flags &
1428 BDRV_O_CACHE_WB);
1429 reopen_state->bs->read_only = !(reopen_state->flags & BDRV_O_RDWR);
1430}
1431
1432/*
1433 * Abort the reopen, and delete and free the staged changes in
1434 * reopen_state
1435 */
1436void bdrv_reopen_abort(BDRVReopenState *reopen_state)
1437{
1438 BlockDriver *drv;
1439
1440 assert(reopen_state != NULL);
1441 drv = reopen_state->bs->drv;
1442 assert(drv != NULL);
1443
1444 if (drv->bdrv_reopen_abort) {
1445 drv->bdrv_reopen_abort(reopen_state);
1446 }
1447}
1448
1449
fc01f7e7
FB
1450void bdrv_close(BlockDriverState *bs)
1451{
3cbc002c
PB
1452 if (bs->job) {
1453 block_job_cancel_sync(bs->job);
1454 }
58fda173
SH
1455 bdrv_drain_all(); /* complete I/O */
1456 bdrv_flush(bs);
1457 bdrv_drain_all(); /* in case flush left pending I/O */
d7d512f6 1458 notifier_list_notify(&bs->close_notifiers, bs);
7094f12f 1459
3cbc002c 1460 if (bs->drv) {
557df6ac 1461 if (bs->backing_hd) {
4f6fd349 1462 bdrv_unref(bs->backing_hd);
557df6ac
SH
1463 bs->backing_hd = NULL;
1464 }
ea2384d3 1465 bs->drv->bdrv_close(bs);
7267c094 1466 g_free(bs->opaque);
ea2384d3
FB
1467#ifdef _WIN32
1468 if (bs->is_temporary) {
1469 unlink(bs->filename);
1470 }
67b915a5 1471#endif
ea2384d3
FB
1472 bs->opaque = NULL;
1473 bs->drv = NULL;
53fec9d3 1474 bs->copy_on_read = 0;
a275fa42
PB
1475 bs->backing_file[0] = '\0';
1476 bs->backing_format[0] = '\0';
6405875c
PB
1477 bs->total_sectors = 0;
1478 bs->encrypted = 0;
1479 bs->valid_key = 0;
1480 bs->sg = 0;
1481 bs->growable = 0;
0d51b4de 1482 bs->zero_beyond_eof = false;
de9c0cec
KW
1483 QDECREF(bs->options);
1484 bs->options = NULL;
b338082b 1485
66f82cee 1486 if (bs->file != NULL) {
4f6fd349 1487 bdrv_unref(bs->file);
0ac9377d 1488 bs->file = NULL;
66f82cee 1489 }
b338082b 1490 }
98f90dba 1491
9ca11154
PH
1492 bdrv_dev_change_media_cb(bs, false);
1493
98f90dba
ZYW
1494 /*throttling disk I/O limits*/
1495 if (bs->io_limits_enabled) {
1496 bdrv_io_limits_disable(bs);
1497 }
b338082b
FB
1498}
1499
2bc93fed
MK
1500void bdrv_close_all(void)
1501{
1502 BlockDriverState *bs;
1503
1504 QTAILQ_FOREACH(bs, &bdrv_states, list) {
1505 bdrv_close(bs);
1506 }
1507}
1508
88266f5a
SH
1509/* Check if any requests are in-flight (including throttled requests) */
1510static bool bdrv_requests_pending(BlockDriverState *bs)
1511{
1512 if (!QLIST_EMPTY(&bs->tracked_requests)) {
1513 return true;
1514 }
cc0681c4
BC
1515 if (!qemu_co_queue_empty(&bs->throttled_reqs[0])) {
1516 return true;
1517 }
1518 if (!qemu_co_queue_empty(&bs->throttled_reqs[1])) {
88266f5a
SH
1519 return true;
1520 }
1521 if (bs->file && bdrv_requests_pending(bs->file)) {
1522 return true;
1523 }
1524 if (bs->backing_hd && bdrv_requests_pending(bs->backing_hd)) {
1525 return true;
1526 }
1527 return false;
1528}
1529
1530static bool bdrv_requests_pending_all(void)
1531{
1532 BlockDriverState *bs;
1533 QTAILQ_FOREACH(bs, &bdrv_states, list) {
1534 if (bdrv_requests_pending(bs)) {
1535 return true;
1536 }
1537 }
1538 return false;
1539}
1540
922453bc
SH
1541/*
1542 * Wait for pending requests to complete across all BlockDriverStates
1543 *
1544 * This function does not flush data to disk, use bdrv_flush_all() for that
1545 * after calling this function.
4c355d53
ZYW
1546 *
1547 * Note that completion of an asynchronous I/O operation can trigger any
1548 * number of other I/O operations on other devices---for example a coroutine
1549 * can be arbitrarily complex and a constant flow of I/O can come until the
1550 * coroutine is complete. Because of this, it is not possible to have a
1551 * function to drain a single device's I/O queue.
922453bc
SH
1552 */
1553void bdrv_drain_all(void)
1554{
88266f5a
SH
1555 /* Always run first iteration so any pending completion BHs run */
1556 bool busy = true;
922453bc
SH
1557 BlockDriverState *bs;
1558
88266f5a 1559 while (busy) {
4c355d53
ZYW
1560 /* FIXME: We do not have timer support here, so this is effectively
1561 * a busy wait.
1562 */
1563 QTAILQ_FOREACH(bs, &bdrv_states, list) {
cc0681c4 1564 if (bdrv_start_throttled_reqs(bs)) {
4c355d53
ZYW
1565 busy = true;
1566 }
1567 }
922453bc 1568
88266f5a
SH
1569 busy = bdrv_requests_pending_all();
1570 busy |= aio_poll(qemu_get_aio_context(), busy);
922453bc
SH
1571 }
1572}
1573
d22b2f41
RH
1574/* make a BlockDriverState anonymous by removing from bdrv_state list.
1575 Also, NULL terminate the device_name to prevent double remove */
1576void bdrv_make_anon(BlockDriverState *bs)
1577{
1578 if (bs->device_name[0] != '\0') {
1579 QTAILQ_REMOVE(&bdrv_states, bs, list);
1580 }
1581 bs->device_name[0] = '\0';
1582}
1583
e023b2e2
PB
1584static void bdrv_rebind(BlockDriverState *bs)
1585{
1586 if (bs->drv && bs->drv->bdrv_rebind) {
1587 bs->drv->bdrv_rebind(bs);
1588 }
1589}
1590
4ddc07ca
PB
1591static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
1592 BlockDriverState *bs_src)
8802d1fd 1593{
4ddc07ca
PB
1594 /* move some fields that need to stay attached to the device */
1595 bs_dest->open_flags = bs_src->open_flags;
8802d1fd
JC
1596
1597 /* dev info */
4ddc07ca
PB
1598 bs_dest->dev_ops = bs_src->dev_ops;
1599 bs_dest->dev_opaque = bs_src->dev_opaque;
1600 bs_dest->dev = bs_src->dev;
1601 bs_dest->buffer_alignment = bs_src->buffer_alignment;
1602 bs_dest->copy_on_read = bs_src->copy_on_read;
8802d1fd 1603
4ddc07ca 1604 bs_dest->enable_write_cache = bs_src->enable_write_cache;
c4a248a1 1605
cc0681c4
BC
1606 /* i/o throttled req */
1607 memcpy(&bs_dest->throttle_state,
1608 &bs_src->throttle_state,
1609 sizeof(ThrottleState));
1610 bs_dest->throttled_reqs[0] = bs_src->throttled_reqs[0];
1611 bs_dest->throttled_reqs[1] = bs_src->throttled_reqs[1];
4ddc07ca 1612 bs_dest->io_limits_enabled = bs_src->io_limits_enabled;
8802d1fd 1613
8802d1fd 1614 /* r/w error */
4ddc07ca
PB
1615 bs_dest->on_read_error = bs_src->on_read_error;
1616 bs_dest->on_write_error = bs_src->on_write_error;
8802d1fd
JC
1617
1618 /* i/o status */
4ddc07ca
PB
1619 bs_dest->iostatus_enabled = bs_src->iostatus_enabled;
1620 bs_dest->iostatus = bs_src->iostatus;
8802d1fd 1621
a9fc4408 1622 /* dirty bitmap */
e4654d2d 1623 bs_dest->dirty_bitmaps = bs_src->dirty_bitmaps;
a9fc4408 1624
9fcb0251
FZ
1625 /* reference count */
1626 bs_dest->refcnt = bs_src->refcnt;
1627
a9fc4408 1628 /* job */
4ddc07ca
PB
1629 bs_dest->in_use = bs_src->in_use;
1630 bs_dest->job = bs_src->job;
a9fc4408 1631
8802d1fd 1632 /* keep the same entry in bdrv_states */
4ddc07ca
PB
1633 pstrcpy(bs_dest->device_name, sizeof(bs_dest->device_name),
1634 bs_src->device_name);
1635 bs_dest->list = bs_src->list;
1636}
8802d1fd 1637
4ddc07ca
PB
1638/*
1639 * Swap bs contents for two image chains while they are live,
1640 * while keeping required fields on the BlockDriverState that is
1641 * actually attached to a device.
1642 *
1643 * This will modify the BlockDriverState fields, and swap contents
1644 * between bs_new and bs_old. Both bs_new and bs_old are modified.
1645 *
1646 * bs_new is required to be anonymous.
1647 *
1648 * This function does not create any image files.
1649 */
1650void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
1651{
1652 BlockDriverState tmp;
f6801b83 1653
4ddc07ca
PB
1654 /* bs_new must be anonymous and shouldn't have anything fancy enabled */
1655 assert(bs_new->device_name[0] == '\0');
e4654d2d 1656 assert(QLIST_EMPTY(&bs_new->dirty_bitmaps));
4ddc07ca
PB
1657 assert(bs_new->job == NULL);
1658 assert(bs_new->dev == NULL);
1659 assert(bs_new->in_use == 0);
1660 assert(bs_new->io_limits_enabled == false);
cc0681c4 1661 assert(!throttle_have_timer(&bs_new->throttle_state));
8802d1fd 1662
4ddc07ca
PB
1663 tmp = *bs_new;
1664 *bs_new = *bs_old;
1665 *bs_old = tmp;
a9fc4408 1666
4ddc07ca
PB
1667 /* there are some fields that should not be swapped, move them back */
1668 bdrv_move_feature_fields(&tmp, bs_old);
1669 bdrv_move_feature_fields(bs_old, bs_new);
1670 bdrv_move_feature_fields(bs_new, &tmp);
8802d1fd 1671
4ddc07ca
PB
1672 /* bs_new shouldn't be in bdrv_states even after the swap! */
1673 assert(bs_new->device_name[0] == '\0');
1674
1675 /* Check a few fields that should remain attached to the device */
1676 assert(bs_new->dev == NULL);
1677 assert(bs_new->job == NULL);
1678 assert(bs_new->in_use == 0);
1679 assert(bs_new->io_limits_enabled == false);
cc0681c4 1680 assert(!throttle_have_timer(&bs_new->throttle_state));
e023b2e2
PB
1681
1682 bdrv_rebind(bs_new);
4ddc07ca
PB
1683 bdrv_rebind(bs_old);
1684}
1685
1686/*
1687 * Add new bs contents at the top of an image chain while the chain is
1688 * live, while keeping required fields on the top layer.
1689 *
1690 * This will modify the BlockDriverState fields, and swap contents
1691 * between bs_new and bs_top. Both bs_new and bs_top are modified.
1692 *
1693 * bs_new is required to be anonymous.
1694 *
1695 * This function does not create any image files.
1696 */
1697void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top)
1698{
1699 bdrv_swap(bs_new, bs_top);
1700
1701 /* The contents of 'tmp' will become bs_top, as we are
1702 * swapping bs_new and bs_top contents. */
1703 bs_top->backing_hd = bs_new;
1704 bs_top->open_flags &= ~BDRV_O_NO_BACKING;
1705 pstrcpy(bs_top->backing_file, sizeof(bs_top->backing_file),
1706 bs_new->filename);
1707 pstrcpy(bs_top->backing_format, sizeof(bs_top->backing_format),
1708 bs_new->drv ? bs_new->drv->format_name : "");
8802d1fd
JC
1709}
1710
4f6fd349 1711static void bdrv_delete(BlockDriverState *bs)
b338082b 1712{
fa879d62 1713 assert(!bs->dev);
3e914655
PB
1714 assert(!bs->job);
1715 assert(!bs->in_use);
4f6fd349 1716 assert(!bs->refcnt);
e4654d2d 1717 assert(QLIST_EMPTY(&bs->dirty_bitmaps));
18846dee 1718
e1b5c52e
SH
1719 bdrv_close(bs);
1720
1b7bdbc1 1721 /* remove from list, if necessary */
d22b2f41 1722 bdrv_make_anon(bs);
34c6f050 1723
7267c094 1724 g_free(bs);
fc01f7e7
FB
1725}
1726
fa879d62
MA
1727int bdrv_attach_dev(BlockDriverState *bs, void *dev)
1728/* TODO change to DeviceState *dev when all users are qdevified */
18846dee 1729{
fa879d62 1730 if (bs->dev) {
18846dee
MA
1731 return -EBUSY;
1732 }
fa879d62 1733 bs->dev = dev;
28a7282a 1734 bdrv_iostatus_reset(bs);
18846dee
MA
1735 return 0;
1736}
1737
fa879d62
MA
1738/* TODO qdevified devices don't use this, remove when devices are qdevified */
1739void bdrv_attach_dev_nofail(BlockDriverState *bs, void *dev)
18846dee 1740{
fa879d62
MA
1741 if (bdrv_attach_dev(bs, dev) < 0) {
1742 abort();
1743 }
1744}
1745
1746void bdrv_detach_dev(BlockDriverState *bs, void *dev)
1747/* TODO change to DeviceState *dev when all users are qdevified */
1748{
1749 assert(bs->dev == dev);
1750 bs->dev = NULL;
0e49de52
MA
1751 bs->dev_ops = NULL;
1752 bs->dev_opaque = NULL;
29e05f20 1753 bs->buffer_alignment = 512;
18846dee
MA
1754}
1755
fa879d62
MA
1756/* TODO change to return DeviceState * when all users are qdevified */
1757void *bdrv_get_attached_dev(BlockDriverState *bs)
18846dee 1758{
fa879d62 1759 return bs->dev;
18846dee
MA
1760}
1761
0e49de52
MA
1762void bdrv_set_dev_ops(BlockDriverState *bs, const BlockDevOps *ops,
1763 void *opaque)
1764{
1765 bs->dev_ops = ops;
1766 bs->dev_opaque = opaque;
1767}
1768
32c81a4a
PB
1769void bdrv_emit_qmp_error_event(const BlockDriverState *bdrv,
1770 enum MonitorEvent ev,
1771 BlockErrorAction action, bool is_read)
329c0a48
LC
1772{
1773 QObject *data;
1774 const char *action_str;
1775
1776 switch (action) {
1777 case BDRV_ACTION_REPORT:
1778 action_str = "report";
1779 break;
1780 case BDRV_ACTION_IGNORE:
1781 action_str = "ignore";
1782 break;
1783 case BDRV_ACTION_STOP:
1784 action_str = "stop";
1785 break;
1786 default:
1787 abort();
1788 }
1789
1790 data = qobject_from_jsonf("{ 'device': %s, 'action': %s, 'operation': %s }",
1791 bdrv->device_name,
1792 action_str,
1793 is_read ? "read" : "write");
32c81a4a 1794 monitor_protocol_event(ev, data);
329c0a48
LC
1795
1796 qobject_decref(data);
1797}
1798
6f382ed2
LC
1799static void bdrv_emit_qmp_eject_event(BlockDriverState *bs, bool ejected)
1800{
1801 QObject *data;
1802
1803 data = qobject_from_jsonf("{ 'device': %s, 'tray-open': %i }",
1804 bdrv_get_device_name(bs), ejected);
1805 monitor_protocol_event(QEVENT_DEVICE_TRAY_MOVED, data);
1806
1807 qobject_decref(data);
1808}
1809
7d4b4ba5 1810static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load)
0e49de52 1811{
145feb17 1812 if (bs->dev_ops && bs->dev_ops->change_media_cb) {
6f382ed2 1813 bool tray_was_closed = !bdrv_dev_is_tray_open(bs);
7d4b4ba5 1814 bs->dev_ops->change_media_cb(bs->dev_opaque, load);
6f382ed2
LC
1815 if (tray_was_closed) {
1816 /* tray open */
1817 bdrv_emit_qmp_eject_event(bs, true);
1818 }
1819 if (load) {
1820 /* tray close */
1821 bdrv_emit_qmp_eject_event(bs, false);
1822 }
145feb17
MA
1823 }
1824}
1825
2c6942fa
MA
1826bool bdrv_dev_has_removable_media(BlockDriverState *bs)
1827{
1828 return !bs->dev || (bs->dev_ops && bs->dev_ops->change_media_cb);
1829}
1830
025ccaa7
PB
1831void bdrv_dev_eject_request(BlockDriverState *bs, bool force)
1832{
1833 if (bs->dev_ops && bs->dev_ops->eject_request_cb) {
1834 bs->dev_ops->eject_request_cb(bs->dev_opaque, force);
1835 }
1836}
1837
e4def80b
MA
1838bool bdrv_dev_is_tray_open(BlockDriverState *bs)
1839{
1840 if (bs->dev_ops && bs->dev_ops->is_tray_open) {
1841 return bs->dev_ops->is_tray_open(bs->dev_opaque);
1842 }
1843 return false;
1844}
1845
145feb17
MA
1846static void bdrv_dev_resize_cb(BlockDriverState *bs)
1847{
1848 if (bs->dev_ops && bs->dev_ops->resize_cb) {
1849 bs->dev_ops->resize_cb(bs->dev_opaque);
0e49de52
MA
1850 }
1851}
1852
f107639a
MA
1853bool bdrv_dev_is_medium_locked(BlockDriverState *bs)
1854{
1855 if (bs->dev_ops && bs->dev_ops->is_medium_locked) {
1856 return bs->dev_ops->is_medium_locked(bs->dev_opaque);
1857 }
1858 return false;
1859}
1860
e97fc193
AL
1861/*
1862 * Run consistency checks on an image
1863 *
e076f338 1864 * Returns 0 if the check could be completed (it doesn't mean that the image is
a1c7273b 1865 * free of errors) or -errno when an internal error occurred. The results of the
e076f338 1866 * check are stored in res.
e97fc193 1867 */
4534ff54 1868int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix)
e97fc193
AL
1869{
1870 if (bs->drv->bdrv_check == NULL) {
1871 return -ENOTSUP;
1872 }
1873
e076f338 1874 memset(res, 0, sizeof(*res));
4534ff54 1875 return bs->drv->bdrv_check(bs, res, fix);
e97fc193
AL
1876}
1877
8a426614
KW
1878#define COMMIT_BUF_SECTORS 2048
1879
33e3963e
FB
1880/* commit COW file into the raw image */
1881int bdrv_commit(BlockDriverState *bs)
1882{
19cb3738 1883 BlockDriver *drv = bs->drv;
8a426614
KW
1884 int64_t sector, total_sectors;
1885 int n, ro, open_flags;
0bce597d 1886 int ret = 0;
8a426614 1887 uint8_t *buf;
c2cba3d9 1888 char filename[PATH_MAX];
33e3963e 1889
19cb3738
FB
1890 if (!drv)
1891 return -ENOMEDIUM;
4dca4b63
NS
1892
1893 if (!bs->backing_hd) {
1894 return -ENOTSUP;
33e3963e
FB
1895 }
1896
2d3735d3
SH
1897 if (bdrv_in_use(bs) || bdrv_in_use(bs->backing_hd)) {
1898 return -EBUSY;
1899 }
1900
4dca4b63 1901 ro = bs->backing_hd->read_only;
c2cba3d9
JM
1902 /* Use pstrcpy (not strncpy): filename must be NUL-terminated. */
1903 pstrcpy(filename, sizeof(filename), bs->backing_hd->filename);
4dca4b63
NS
1904 open_flags = bs->backing_hd->open_flags;
1905
1906 if (ro) {
0bce597d
JC
1907 if (bdrv_reopen(bs->backing_hd, open_flags | BDRV_O_RDWR, NULL)) {
1908 return -EACCES;
4dca4b63 1909 }
ea2384d3 1910 }
33e3963e 1911
6ea44308 1912 total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
7267c094 1913 buf = g_malloc(COMMIT_BUF_SECTORS * BDRV_SECTOR_SIZE);
8a426614
KW
1914
1915 for (sector = 0; sector < total_sectors; sector += n) {
d663640c
PB
1916 ret = bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n);
1917 if (ret < 0) {
1918 goto ro_cleanup;
1919 }
1920 if (ret) {
8a426614
KW
1921 if (bdrv_read(bs, sector, buf, n) != 0) {
1922 ret = -EIO;
1923 goto ro_cleanup;
1924 }
1925
1926 if (bdrv_write(bs->backing_hd, sector, buf, n) != 0) {
1927 ret = -EIO;
1928 goto ro_cleanup;
1929 }
ea2384d3 1930 }
33e3963e 1931 }
95389c86 1932
1d44952f
CH
1933 if (drv->bdrv_make_empty) {
1934 ret = drv->bdrv_make_empty(bs);
1935 bdrv_flush(bs);
1936 }
95389c86 1937
3f5075ae
CH
1938 /*
1939 * Make sure all data we wrote to the backing device is actually
1940 * stable on disk.
1941 */
1942 if (bs->backing_hd)
1943 bdrv_flush(bs->backing_hd);
4dca4b63
NS
1944
1945ro_cleanup:
7267c094 1946 g_free(buf);
4dca4b63
NS
1947
1948 if (ro) {
0bce597d
JC
1949 /* ignoring error return here */
1950 bdrv_reopen(bs->backing_hd, open_flags & ~BDRV_O_RDWR, NULL);
4dca4b63
NS
1951 }
1952
1d44952f 1953 return ret;
33e3963e
FB
1954}
1955
e8877497 1956int bdrv_commit_all(void)
6ab4b5ab
MA
1957{
1958 BlockDriverState *bs;
1959
1960 QTAILQ_FOREACH(bs, &bdrv_states, list) {
272d2d8e
JC
1961 if (bs->drv && bs->backing_hd) {
1962 int ret = bdrv_commit(bs);
1963 if (ret < 0) {
1964 return ret;
1965 }
e8877497 1966 }
6ab4b5ab 1967 }
e8877497 1968 return 0;
6ab4b5ab
MA
1969}
1970
dbffbdcf
SH
1971/**
1972 * Remove an active request from the tracked requests list
1973 *
1974 * This function should be called when a tracked request is completing.
1975 */
1976static void tracked_request_end(BdrvTrackedRequest *req)
1977{
1978 QLIST_REMOVE(req, list);
f4658285 1979 qemu_co_queue_restart_all(&req->wait_queue);
dbffbdcf
SH
1980}
1981
1982/**
1983 * Add an active request to the tracked requests list
1984 */
1985static void tracked_request_begin(BdrvTrackedRequest *req,
1986 BlockDriverState *bs,
1987 int64_t sector_num,
1988 int nb_sectors, bool is_write)
1989{
1990 *req = (BdrvTrackedRequest){
1991 .bs = bs,
1992 .sector_num = sector_num,
1993 .nb_sectors = nb_sectors,
1994 .is_write = is_write,
5f8b6491 1995 .co = qemu_coroutine_self(),
dbffbdcf
SH
1996 };
1997
f4658285
SH
1998 qemu_co_queue_init(&req->wait_queue);
1999
dbffbdcf
SH
2000 QLIST_INSERT_HEAD(&bs->tracked_requests, req, list);
2001}
2002
d83947ac
SH
2003/**
2004 * Round a region to cluster boundaries
2005 */
343bded4
PB
2006void bdrv_round_to_clusters(BlockDriverState *bs,
2007 int64_t sector_num, int nb_sectors,
2008 int64_t *cluster_sector_num,
2009 int *cluster_nb_sectors)
d83947ac
SH
2010{
2011 BlockDriverInfo bdi;
2012
2013 if (bdrv_get_info(bs, &bdi) < 0 || bdi.cluster_size == 0) {
2014 *cluster_sector_num = sector_num;
2015 *cluster_nb_sectors = nb_sectors;
2016 } else {
2017 int64_t c = bdi.cluster_size / BDRV_SECTOR_SIZE;
2018 *cluster_sector_num = QEMU_ALIGN_DOWN(sector_num, c);
2019 *cluster_nb_sectors = QEMU_ALIGN_UP(sector_num - *cluster_sector_num +
2020 nb_sectors, c);
2021 }
2022}
2023
f4658285
SH
2024static bool tracked_request_overlaps(BdrvTrackedRequest *req,
2025 int64_t sector_num, int nb_sectors) {
d83947ac
SH
2026 /* aaaa bbbb */
2027 if (sector_num >= req->sector_num + req->nb_sectors) {
2028 return false;
2029 }
2030 /* bbbb aaaa */
2031 if (req->sector_num >= sector_num + nb_sectors) {
2032 return false;
2033 }
2034 return true;
f4658285
SH
2035}
2036
2037static void coroutine_fn wait_for_overlapping_requests(BlockDriverState *bs,
2038 int64_t sector_num, int nb_sectors)
2039{
2040 BdrvTrackedRequest *req;
d83947ac
SH
2041 int64_t cluster_sector_num;
2042 int cluster_nb_sectors;
f4658285
SH
2043 bool retry;
2044
d83947ac
SH
2045 /* If we touch the same cluster it counts as an overlap. This guarantees
2046 * that allocating writes will be serialized and not race with each other
2047 * for the same cluster. For example, in copy-on-read it ensures that the
2048 * CoR read and write operations are atomic and guest writes cannot
2049 * interleave between them.
2050 */
343bded4
PB
2051 bdrv_round_to_clusters(bs, sector_num, nb_sectors,
2052 &cluster_sector_num, &cluster_nb_sectors);
d83947ac 2053
f4658285
SH
2054 do {
2055 retry = false;
2056 QLIST_FOREACH(req, &bs->tracked_requests, list) {
d83947ac
SH
2057 if (tracked_request_overlaps(req, cluster_sector_num,
2058 cluster_nb_sectors)) {
5f8b6491
SH
2059 /* Hitting this means there was a reentrant request, for
2060 * example, a block driver issuing nested requests. This must
2061 * never happen since it means deadlock.
2062 */
2063 assert(qemu_coroutine_self() != req->co);
2064
f4658285
SH
2065 qemu_co_queue_wait(&req->wait_queue);
2066 retry = true;
2067 break;
2068 }
2069 }
2070 } while (retry);
2071}
2072
756e6736
KW
2073/*
2074 * Return values:
2075 * 0 - success
2076 * -EINVAL - backing format specified, but no file
2077 * -ENOSPC - can't update the backing file because no space is left in the
2078 * image file header
2079 * -ENOTSUP - format driver doesn't support changing the backing file
2080 */
2081int bdrv_change_backing_file(BlockDriverState *bs,
2082 const char *backing_file, const char *backing_fmt)
2083{
2084 BlockDriver *drv = bs->drv;
469ef350 2085 int ret;
756e6736 2086
5f377794
PB
2087 /* Backing file format doesn't make sense without a backing file */
2088 if (backing_fmt && !backing_file) {
2089 return -EINVAL;
2090 }
2091
756e6736 2092 if (drv->bdrv_change_backing_file != NULL) {
469ef350 2093 ret = drv->bdrv_change_backing_file(bs, backing_file, backing_fmt);
756e6736 2094 } else {
469ef350 2095 ret = -ENOTSUP;
756e6736 2096 }
469ef350
PB
2097
2098 if (ret == 0) {
2099 pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: "");
2100 pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: "");
2101 }
2102 return ret;
756e6736
KW
2103}
2104
6ebdcee2
JC
2105/*
2106 * Finds the image layer in the chain that has 'bs' as its backing file.
2107 *
2108 * active is the current topmost image.
2109 *
2110 * Returns NULL if bs is not found in active's image chain,
2111 * or if active == bs.
2112 */
2113BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
2114 BlockDriverState *bs)
2115{
2116 BlockDriverState *overlay = NULL;
2117 BlockDriverState *intermediate;
2118
2119 assert(active != NULL);
2120 assert(bs != NULL);
2121
2122 /* if bs is the same as active, then by definition it has no overlay
2123 */
2124 if (active == bs) {
2125 return NULL;
2126 }
2127
2128 intermediate = active;
2129 while (intermediate->backing_hd) {
2130 if (intermediate->backing_hd == bs) {
2131 overlay = intermediate;
2132 break;
2133 }
2134 intermediate = intermediate->backing_hd;
2135 }
2136
2137 return overlay;
2138}
2139
2140typedef struct BlkIntermediateStates {
2141 BlockDriverState *bs;
2142 QSIMPLEQ_ENTRY(BlkIntermediateStates) entry;
2143} BlkIntermediateStates;
2144
2145
2146/*
2147 * Drops images above 'base' up to and including 'top', and sets the image
2148 * above 'top' to have base as its backing file.
2149 *
2150 * Requires that the overlay to 'top' is opened r/w, so that the backing file
2151 * information in 'bs' can be properly updated.
2152 *
2153 * E.g., this will convert the following chain:
2154 * bottom <- base <- intermediate <- top <- active
2155 *
2156 * to
2157 *
2158 * bottom <- base <- active
2159 *
2160 * It is allowed for bottom==base, in which case it converts:
2161 *
2162 * base <- intermediate <- top <- active
2163 *
2164 * to
2165 *
2166 * base <- active
2167 *
2168 * Error conditions:
2169 * if active == top, that is considered an error
2170 *
2171 */
2172int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
2173 BlockDriverState *base)
2174{
2175 BlockDriverState *intermediate;
2176 BlockDriverState *base_bs = NULL;
2177 BlockDriverState *new_top_bs = NULL;
2178 BlkIntermediateStates *intermediate_state, *next;
2179 int ret = -EIO;
2180
2181 QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete;
2182 QSIMPLEQ_INIT(&states_to_delete);
2183
2184 if (!top->drv || !base->drv) {
2185 goto exit;
2186 }
2187
2188 new_top_bs = bdrv_find_overlay(active, top);
2189
2190 if (new_top_bs == NULL) {
2191 /* we could not find the image above 'top', this is an error */
2192 goto exit;
2193 }
2194
2195 /* special case of new_top_bs->backing_hd already pointing to base - nothing
2196 * to do, no intermediate images */
2197 if (new_top_bs->backing_hd == base) {
2198 ret = 0;
2199 goto exit;
2200 }
2201
2202 intermediate = top;
2203
2204 /* now we will go down through the list, and add each BDS we find
2205 * into our deletion queue, until we hit the 'base'
2206 */
2207 while (intermediate) {
2208 intermediate_state = g_malloc0(sizeof(BlkIntermediateStates));
2209 intermediate_state->bs = intermediate;
2210 QSIMPLEQ_INSERT_TAIL(&states_to_delete, intermediate_state, entry);
2211
2212 if (intermediate->backing_hd == base) {
2213 base_bs = intermediate->backing_hd;
2214 break;
2215 }
2216 intermediate = intermediate->backing_hd;
2217 }
2218 if (base_bs == NULL) {
2219 /* something went wrong, we did not end at the base. safely
2220 * unravel everything, and exit with error */
2221 goto exit;
2222 }
2223
2224 /* success - we can delete the intermediate states, and link top->base */
2225 ret = bdrv_change_backing_file(new_top_bs, base_bs->filename,
2226 base_bs->drv ? base_bs->drv->format_name : "");
2227 if (ret) {
2228 goto exit;
2229 }
2230 new_top_bs->backing_hd = base_bs;
2231
2232
2233 QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
2234 /* so that bdrv_close() does not recursively close the chain */
2235 intermediate_state->bs->backing_hd = NULL;
4f6fd349 2236 bdrv_unref(intermediate_state->bs);
6ebdcee2
JC
2237 }
2238 ret = 0;
2239
2240exit:
2241 QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
2242 g_free(intermediate_state);
2243 }
2244 return ret;
2245}
2246
2247
71d0770c
AL
2248static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
2249 size_t size)
2250{
2251 int64_t len;
2252
2253 if (!bdrv_is_inserted(bs))
2254 return -ENOMEDIUM;
2255
2256 if (bs->growable)
2257 return 0;
2258
2259 len = bdrv_getlength(bs);
2260
fbb7b4e0
KW
2261 if (offset < 0)
2262 return -EIO;
2263
2264 if ((offset > len) || (len - offset < size))
71d0770c
AL
2265 return -EIO;
2266
2267 return 0;
2268}
2269
2270static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
2271 int nb_sectors)
2272{
eb5a3165
JS
2273 return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE,
2274 nb_sectors * BDRV_SECTOR_SIZE);
71d0770c
AL
2275}
2276
1c9805a3
SH
2277typedef struct RwCo {
2278 BlockDriverState *bs;
2279 int64_t sector_num;
2280 int nb_sectors;
2281 QEMUIOVector *qiov;
2282 bool is_write;
2283 int ret;
4105eaaa 2284 BdrvRequestFlags flags;
1c9805a3
SH
2285} RwCo;
2286
2287static void coroutine_fn bdrv_rw_co_entry(void *opaque)
fc01f7e7 2288{
1c9805a3 2289 RwCo *rwco = opaque;
ea2384d3 2290
1c9805a3
SH
2291 if (!rwco->is_write) {
2292 rwco->ret = bdrv_co_do_readv(rwco->bs, rwco->sector_num,
4105eaaa
PL
2293 rwco->nb_sectors, rwco->qiov,
2294 rwco->flags);
1c9805a3
SH
2295 } else {
2296 rwco->ret = bdrv_co_do_writev(rwco->bs, rwco->sector_num,
4105eaaa
PL
2297 rwco->nb_sectors, rwco->qiov,
2298 rwco->flags);
1c9805a3
SH
2299 }
2300}
e7a8a783 2301
1c9805a3 2302/*
8d3b1a2d 2303 * Process a vectored synchronous request using coroutines
1c9805a3 2304 */
8d3b1a2d 2305static int bdrv_rwv_co(BlockDriverState *bs, int64_t sector_num,
4105eaaa
PL
2306 QEMUIOVector *qiov, bool is_write,
2307 BdrvRequestFlags flags)
1c9805a3 2308{
1c9805a3
SH
2309 Coroutine *co;
2310 RwCo rwco = {
2311 .bs = bs,
2312 .sector_num = sector_num,
8d3b1a2d
KW
2313 .nb_sectors = qiov->size >> BDRV_SECTOR_BITS,
2314 .qiov = qiov,
1c9805a3
SH
2315 .is_write = is_write,
2316 .ret = NOT_DONE,
4105eaaa 2317 .flags = flags,
1c9805a3 2318 };
8d3b1a2d 2319 assert((qiov->size & (BDRV_SECTOR_SIZE - 1)) == 0);
e7a8a783 2320
498e386c
ZYW
2321 /**
2322 * In sync call context, when the vcpu is blocked, this throttling timer
2323 * will not fire; so the I/O throttling function has to be disabled here
2324 * if it has been enabled.
2325 */
2326 if (bs->io_limits_enabled) {
2327 fprintf(stderr, "Disabling I/O throttling on '%s' due "
2328 "to synchronous I/O.\n", bdrv_get_device_name(bs));
2329 bdrv_io_limits_disable(bs);
2330 }
2331
1c9805a3
SH
2332 if (qemu_in_coroutine()) {
2333 /* Fast-path if already in coroutine context */
2334 bdrv_rw_co_entry(&rwco);
2335 } else {
2336 co = qemu_coroutine_create(bdrv_rw_co_entry);
2337 qemu_coroutine_enter(co, &rwco);
2338 while (rwco.ret == NOT_DONE) {
2339 qemu_aio_wait();
2340 }
2341 }
2342 return rwco.ret;
2343}
b338082b 2344
8d3b1a2d
KW
2345/*
2346 * Process a synchronous request using coroutines
2347 */
2348static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf,
4105eaaa 2349 int nb_sectors, bool is_write, BdrvRequestFlags flags)
8d3b1a2d
KW
2350{
2351 QEMUIOVector qiov;
2352 struct iovec iov = {
2353 .iov_base = (void *)buf,
2354 .iov_len = nb_sectors * BDRV_SECTOR_SIZE,
2355 };
2356
2357 qemu_iovec_init_external(&qiov, &iov, 1);
4105eaaa 2358 return bdrv_rwv_co(bs, sector_num, &qiov, is_write, flags);
8d3b1a2d
KW
2359}
2360
1c9805a3
SH
2361/* return < 0 if error. See bdrv_write() for the return codes */
2362int bdrv_read(BlockDriverState *bs, int64_t sector_num,
2363 uint8_t *buf, int nb_sectors)
2364{
4105eaaa 2365 return bdrv_rw_co(bs, sector_num, buf, nb_sectors, false, 0);
fc01f7e7
FB
2366}
2367
07d27a44
MA
2368/* Just like bdrv_read(), but with I/O throttling temporarily disabled */
2369int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
2370 uint8_t *buf, int nb_sectors)
2371{
2372 bool enabled;
2373 int ret;
2374
2375 enabled = bs->io_limits_enabled;
2376 bs->io_limits_enabled = false;
4e7395e8 2377 ret = bdrv_read(bs, sector_num, buf, nb_sectors);
07d27a44
MA
2378 bs->io_limits_enabled = enabled;
2379 return ret;
2380}
2381
5fafdf24 2382/* Return < 0 if error. Important errors are:
19cb3738
FB
2383 -EIO generic I/O error (may happen for all errors)
2384 -ENOMEDIUM No media inserted.
2385 -EINVAL Invalid sector number or nb_sectors
2386 -EACCES Trying to write a read-only device
2387*/
5fafdf24 2388int bdrv_write(BlockDriverState *bs, int64_t sector_num,
fc01f7e7
FB
2389 const uint8_t *buf, int nb_sectors)
2390{
4105eaaa 2391 return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true, 0);
83f64091
FB
2392}
2393
8d3b1a2d
KW
2394int bdrv_writev(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov)
2395{
4105eaaa
PL
2396 return bdrv_rwv_co(bs, sector_num, qiov, true, 0);
2397}
2398
aa7bfbff
PL
2399int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num,
2400 int nb_sectors, BdrvRequestFlags flags)
4105eaaa
PL
2401{
2402 return bdrv_rw_co(bs, sector_num, NULL, nb_sectors, true,
aa7bfbff 2403 BDRV_REQ_ZERO_WRITE | flags);
8d3b1a2d
KW
2404}
2405
d75cbb5e
PL
2406/*
2407 * Completely zero out a block device with the help of bdrv_write_zeroes.
2408 * The operation is sped up by checking the block status and only writing
2409 * zeroes to the device if they currently do not return zeroes. Optional
2410 * flags are passed through to bdrv_write_zeroes (e.g. BDRV_REQ_MAY_UNMAP).
2411 *
2412 * Returns < 0 on error, 0 on success. For error codes see bdrv_write().
2413 */
2414int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags)
2415{
2416 int64_t target_size = bdrv_getlength(bs) / BDRV_SECTOR_SIZE;
2417 int64_t ret, nb_sectors, sector_num = 0;
2418 int n;
2419
2420 for (;;) {
2421 nb_sectors = target_size - sector_num;
2422 if (nb_sectors <= 0) {
2423 return 0;
2424 }
2425 if (nb_sectors > INT_MAX) {
2426 nb_sectors = INT_MAX;
2427 }
2428 ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &n);
2429 if (ret & BDRV_BLOCK_ZERO) {
2430 sector_num += n;
2431 continue;
2432 }
2433 ret = bdrv_write_zeroes(bs, sector_num, n, flags);
2434 if (ret < 0) {
2435 error_report("error writing zeroes at sector %" PRId64 ": %s",
2436 sector_num, strerror(-ret));
2437 return ret;
2438 }
2439 sector_num += n;
2440 }
2441}
2442
eda578e5
AL
2443int bdrv_pread(BlockDriverState *bs, int64_t offset,
2444 void *buf, int count1)
83f64091 2445{
6ea44308 2446 uint8_t tmp_buf[BDRV_SECTOR_SIZE];
83f64091
FB
2447 int len, nb_sectors, count;
2448 int64_t sector_num;
9a8c4cce 2449 int ret;
83f64091
FB
2450
2451 count = count1;
2452 /* first read to align to sector start */
6ea44308 2453 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
83f64091
FB
2454 if (len > count)
2455 len = count;
6ea44308 2456 sector_num = offset >> BDRV_SECTOR_BITS;
83f64091 2457 if (len > 0) {
9a8c4cce
KW
2458 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
2459 return ret;
6ea44308 2460 memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len);
83f64091
FB
2461 count -= len;
2462 if (count == 0)
2463 return count1;
2464 sector_num++;
2465 buf += len;
2466 }
2467
2468 /* read the sectors "in place" */
6ea44308 2469 nb_sectors = count >> BDRV_SECTOR_BITS;
83f64091 2470 if (nb_sectors > 0) {
9a8c4cce
KW
2471 if ((ret = bdrv_read(bs, sector_num, buf, nb_sectors)) < 0)
2472 return ret;
83f64091 2473 sector_num += nb_sectors;
6ea44308 2474 len = nb_sectors << BDRV_SECTOR_BITS;
83f64091
FB
2475 buf += len;
2476 count -= len;
2477 }
2478
2479 /* add data from the last sector */
2480 if (count > 0) {
9a8c4cce
KW
2481 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
2482 return ret;
83f64091
FB
2483 memcpy(buf, tmp_buf, count);
2484 }
2485 return count1;
2486}
2487
8d3b1a2d 2488int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov)
83f64091 2489{
6ea44308 2490 uint8_t tmp_buf[BDRV_SECTOR_SIZE];
83f64091
FB
2491 int len, nb_sectors, count;
2492 int64_t sector_num;
9a8c4cce 2493 int ret;
83f64091 2494
8d3b1a2d
KW
2495 count = qiov->size;
2496
83f64091 2497 /* first write to align to sector start */
6ea44308 2498 len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
83f64091
FB
2499 if (len > count)
2500 len = count;
6ea44308 2501 sector_num = offset >> BDRV_SECTOR_BITS;
83f64091 2502 if (len > 0) {
9a8c4cce
KW
2503 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
2504 return ret;
8d3b1a2d
KW
2505 qemu_iovec_to_buf(qiov, 0, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)),
2506 len);
9a8c4cce
KW
2507 if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
2508 return ret;
83f64091
FB
2509 count -= len;
2510 if (count == 0)
8d3b1a2d 2511 return qiov->size;
83f64091 2512 sector_num++;
83f64091
FB
2513 }
2514
2515 /* write the sectors "in place" */
6ea44308 2516 nb_sectors = count >> BDRV_SECTOR_BITS;
83f64091 2517 if (nb_sectors > 0) {
8d3b1a2d
KW
2518 QEMUIOVector qiov_inplace;
2519
2520 qemu_iovec_init(&qiov_inplace, qiov->niov);
2521 qemu_iovec_concat(&qiov_inplace, qiov, len,
2522 nb_sectors << BDRV_SECTOR_BITS);
2523 ret = bdrv_writev(bs, sector_num, &qiov_inplace);
2524 qemu_iovec_destroy(&qiov_inplace);
2525 if (ret < 0) {
9a8c4cce 2526 return ret;
8d3b1a2d
KW
2527 }
2528
83f64091 2529 sector_num += nb_sectors;
6ea44308 2530 len = nb_sectors << BDRV_SECTOR_BITS;
83f64091
FB
2531 count -= len;
2532 }
2533
2534 /* add data from the last sector */
2535 if (count > 0) {
9a8c4cce
KW
2536 if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
2537 return ret;
8d3b1a2d 2538 qemu_iovec_to_buf(qiov, qiov->size - count, tmp_buf, count);
9a8c4cce
KW
2539 if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
2540 return ret;
83f64091 2541 }
8d3b1a2d
KW
2542 return qiov->size;
2543}
2544
2545int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
2546 const void *buf, int count1)
2547{
2548 QEMUIOVector qiov;
2549 struct iovec iov = {
2550 .iov_base = (void *) buf,
2551 .iov_len = count1,
2552 };
2553
2554 qemu_iovec_init_external(&qiov, &iov, 1);
2555 return bdrv_pwritev(bs, offset, &qiov);
83f64091 2556}
83f64091 2557
f08145fe
KW
2558/*
2559 * Writes to the file and ensures that no writes are reordered across this
2560 * request (acts as a barrier)
2561 *
2562 * Returns 0 on success, -errno in error cases.
2563 */
2564int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
2565 const void *buf, int count)
2566{
2567 int ret;
2568
2569 ret = bdrv_pwrite(bs, offset, buf, count);
2570 if (ret < 0) {
2571 return ret;
2572 }
2573
f05fa4ad
PB
2574 /* No flush needed for cache modes that already do it */
2575 if (bs->enable_write_cache) {
f08145fe
KW
2576 bdrv_flush(bs);
2577 }
2578
2579 return 0;
2580}
2581
470c0504 2582static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs,
ab185921
SH
2583 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
2584{
2585 /* Perform I/O through a temporary buffer so that users who scribble over
2586 * their read buffer while the operation is in progress do not end up
2587 * modifying the image file. This is critical for zero-copy guest I/O
2588 * where anything might happen inside guest memory.
2589 */
2590 void *bounce_buffer;
2591
79c053bd 2592 BlockDriver *drv = bs->drv;
ab185921
SH
2593 struct iovec iov;
2594 QEMUIOVector bounce_qiov;
2595 int64_t cluster_sector_num;
2596 int cluster_nb_sectors;
2597 size_t skip_bytes;
2598 int ret;
2599
2600 /* Cover entire cluster so no additional backing file I/O is required when
2601 * allocating cluster in the image file.
2602 */
343bded4
PB
2603 bdrv_round_to_clusters(bs, sector_num, nb_sectors,
2604 &cluster_sector_num, &cluster_nb_sectors);
ab185921 2605
470c0504
SH
2606 trace_bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors,
2607 cluster_sector_num, cluster_nb_sectors);
ab185921
SH
2608
2609 iov.iov_len = cluster_nb_sectors * BDRV_SECTOR_SIZE;
2610 iov.iov_base = bounce_buffer = qemu_blockalign(bs, iov.iov_len);
2611 qemu_iovec_init_external(&bounce_qiov, &iov, 1);
2612
79c053bd
SH
2613 ret = drv->bdrv_co_readv(bs, cluster_sector_num, cluster_nb_sectors,
2614 &bounce_qiov);
ab185921
SH
2615 if (ret < 0) {
2616 goto err;
2617 }
2618
79c053bd
SH
2619 if (drv->bdrv_co_write_zeroes &&
2620 buffer_is_zero(bounce_buffer, iov.iov_len)) {
621f0589 2621 ret = bdrv_co_do_write_zeroes(bs, cluster_sector_num,
aa7bfbff 2622 cluster_nb_sectors, 0);
79c053bd 2623 } else {
f05fa4ad
PB
2624 /* This does not change the data on the disk, it is not necessary
2625 * to flush even in cache=writethrough mode.
2626 */
79c053bd 2627 ret = drv->bdrv_co_writev(bs, cluster_sector_num, cluster_nb_sectors,
ab185921 2628 &bounce_qiov);
79c053bd
SH
2629 }
2630
ab185921
SH
2631 if (ret < 0) {
2632 /* It might be okay to ignore write errors for guest requests. If this
2633 * is a deliberate copy-on-read then we don't want to ignore the error.
2634 * Simply report it in all cases.
2635 */
2636 goto err;
2637 }
2638
2639 skip_bytes = (sector_num - cluster_sector_num) * BDRV_SECTOR_SIZE;
03396148
MT
2640 qemu_iovec_from_buf(qiov, 0, bounce_buffer + skip_bytes,
2641 nb_sectors * BDRV_SECTOR_SIZE);
ab185921
SH
2642
2643err:
2644 qemu_vfree(bounce_buffer);
2645 return ret;
2646}
2647
c5fbe571
SH
2648/*
2649 * Handle a read request in coroutine context
2650 */
2651static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs,
470c0504
SH
2652 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
2653 BdrvRequestFlags flags)
da1fa91d
KW
2654{
2655 BlockDriver *drv = bs->drv;
dbffbdcf
SH
2656 BdrvTrackedRequest req;
2657 int ret;
da1fa91d 2658
da1fa91d
KW
2659 if (!drv) {
2660 return -ENOMEDIUM;
2661 }
2662 if (bdrv_check_request(bs, sector_num, nb_sectors)) {
2663 return -EIO;
2664 }
2665
f4658285 2666 if (bs->copy_on_read) {
470c0504
SH
2667 flags |= BDRV_REQ_COPY_ON_READ;
2668 }
2669 if (flags & BDRV_REQ_COPY_ON_READ) {
2670 bs->copy_on_read_in_flight++;
2671 }
2672
2673 if (bs->copy_on_read_in_flight) {
f4658285
SH
2674 wait_for_overlapping_requests(bs, sector_num, nb_sectors);
2675 }
2676
cc0681c4
BC
2677 /* throttling disk I/O */
2678 if (bs->io_limits_enabled) {
2679 bdrv_io_limits_intercept(bs, nb_sectors, false);
2680 }
2681
dbffbdcf 2682 tracked_request_begin(&req, bs, sector_num, nb_sectors, false);
ab185921 2683
470c0504 2684 if (flags & BDRV_REQ_COPY_ON_READ) {
ab185921
SH
2685 int pnum;
2686
bdad13b9 2687 ret = bdrv_is_allocated(bs, sector_num, nb_sectors, &pnum);
ab185921
SH
2688 if (ret < 0) {
2689 goto out;
2690 }
2691
2692 if (!ret || pnum != nb_sectors) {
470c0504 2693 ret = bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, qiov);
ab185921
SH
2694 goto out;
2695 }
2696 }
2697
893a8f62
MK
2698 if (!(bs->zero_beyond_eof && bs->growable)) {
2699 ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov);
2700 } else {
2701 /* Read zeros after EOF of growable BDSes */
2702 int64_t len, total_sectors, max_nb_sectors;
2703
2704 len = bdrv_getlength(bs);
2705 if (len < 0) {
2706 ret = len;
2707 goto out;
2708 }
2709
d055a1fe 2710 total_sectors = DIV_ROUND_UP(len, BDRV_SECTOR_SIZE);
893a8f62
MK
2711 max_nb_sectors = MAX(0, total_sectors - sector_num);
2712 if (max_nb_sectors > 0) {
2713 ret = drv->bdrv_co_readv(bs, sector_num,
2714 MIN(nb_sectors, max_nb_sectors), qiov);
2715 } else {
2716 ret = 0;
2717 }
2718
2719 /* Reading beyond end of file is supposed to produce zeroes */
2720 if (ret == 0 && total_sectors < sector_num + nb_sectors) {
2721 uint64_t offset = MAX(0, total_sectors - sector_num);
2722 uint64_t bytes = (sector_num + nb_sectors - offset) *
2723 BDRV_SECTOR_SIZE;
2724 qemu_iovec_memset(qiov, offset * BDRV_SECTOR_SIZE, 0, bytes);
2725 }
2726 }
ab185921
SH
2727
2728out:
dbffbdcf 2729 tracked_request_end(&req);
470c0504
SH
2730
2731 if (flags & BDRV_REQ_COPY_ON_READ) {
2732 bs->copy_on_read_in_flight--;
2733 }
2734
dbffbdcf 2735 return ret;
da1fa91d
KW
2736}
2737
c5fbe571 2738int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num,
da1fa91d
KW
2739 int nb_sectors, QEMUIOVector *qiov)
2740{
c5fbe571 2741 trace_bdrv_co_readv(bs, sector_num, nb_sectors);
da1fa91d 2742
470c0504
SH
2743 return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 0);
2744}
2745
2746int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
2747 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
2748{
2749 trace_bdrv_co_copy_on_readv(bs, sector_num, nb_sectors);
2750
2751 return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov,
2752 BDRV_REQ_COPY_ON_READ);
c5fbe571
SH
2753}
2754
c31cb707
PL
2755/* if no limit is specified in the BlockLimits use a default
2756 * of 32768 512-byte sectors (16 MiB) per request.
2757 */
2758#define MAX_WRITE_ZEROES_DEFAULT 32768
2759
f08f2dda 2760static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs,
aa7bfbff 2761 int64_t sector_num, int nb_sectors, BdrvRequestFlags flags)
f08f2dda
SH
2762{
2763 BlockDriver *drv = bs->drv;
2764 QEMUIOVector qiov;
c31cb707
PL
2765 struct iovec iov = {0};
2766 int ret = 0;
f08f2dda 2767
c31cb707
PL
2768 int max_write_zeroes = bs->bl.max_write_zeroes ?
2769 bs->bl.max_write_zeroes : MAX_WRITE_ZEROES_DEFAULT;
621f0589 2770
c31cb707
PL
2771 while (nb_sectors > 0 && !ret) {
2772 int num = nb_sectors;
2773
2774 /* align request */
2775 if (bs->bl.write_zeroes_alignment &&
2776 num >= bs->bl.write_zeroes_alignment &&
2777 sector_num % bs->bl.write_zeroes_alignment) {
2778 if (num > bs->bl.write_zeroes_alignment) {
2779 num = bs->bl.write_zeroes_alignment;
2780 }
2781 num -= sector_num % bs->bl.write_zeroes_alignment;
621f0589 2782 }
f08f2dda 2783
c31cb707
PL
2784 /* limit request size */
2785 if (num > max_write_zeroes) {
2786 num = max_write_zeroes;
2787 }
2788
2789 ret = -ENOTSUP;
2790 /* First try the efficient write zeroes operation */
2791 if (drv->bdrv_co_write_zeroes) {
2792 ret = drv->bdrv_co_write_zeroes(bs, sector_num, num, flags);
2793 }
2794
2795 if (ret == -ENOTSUP) {
2796 /* Fall back to bounce buffer if write zeroes is unsupported */
2797 iov.iov_len = num * BDRV_SECTOR_SIZE;
2798 if (iov.iov_base == NULL) {
2799 /* allocate bounce buffer only once and ensure that it
2800 * is big enough for this and all future requests.
2801 */
2802 size_t bufsize = num <= nb_sectors ? num : max_write_zeroes;
2803 iov.iov_base = qemu_blockalign(bs, bufsize * BDRV_SECTOR_SIZE);
2804 memset(iov.iov_base, 0, bufsize * BDRV_SECTOR_SIZE);
2805 }
2806 qemu_iovec_init_external(&qiov, &iov, 1);
f08f2dda 2807
c31cb707
PL
2808 ret = drv->bdrv_co_writev(bs, sector_num, num, &qiov);
2809 }
2810
2811 sector_num += num;
2812 nb_sectors -= num;
2813 }
f08f2dda
SH
2814
2815 qemu_vfree(iov.iov_base);
2816 return ret;
2817}
2818
c5fbe571
SH
2819/*
2820 * Handle a write request in coroutine context
2821 */
2822static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs,
f08f2dda
SH
2823 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
2824 BdrvRequestFlags flags)
c5fbe571
SH
2825{
2826 BlockDriver *drv = bs->drv;
dbffbdcf 2827 BdrvTrackedRequest req;
6b7cb247 2828 int ret;
da1fa91d
KW
2829
2830 if (!bs->drv) {
2831 return -ENOMEDIUM;
2832 }
2833 if (bs->read_only) {
2834 return -EACCES;
2835 }
2836 if (bdrv_check_request(bs, sector_num, nb_sectors)) {
2837 return -EIO;
2838 }
2839
470c0504 2840 if (bs->copy_on_read_in_flight) {
f4658285
SH
2841 wait_for_overlapping_requests(bs, sector_num, nb_sectors);
2842 }
2843
cc0681c4
BC
2844 /* throttling disk I/O */
2845 if (bs->io_limits_enabled) {
2846 bdrv_io_limits_intercept(bs, nb_sectors, true);
2847 }
2848
dbffbdcf
SH
2849 tracked_request_begin(&req, bs, sector_num, nb_sectors, true);
2850
d616b224
SH
2851 ret = notifier_with_return_list_notify(&bs->before_write_notifiers, &req);
2852
2853 if (ret < 0) {
2854 /* Do nothing, write notifier decided to fail this request */
2855 } else if (flags & BDRV_REQ_ZERO_WRITE) {
aa7bfbff 2856 ret = bdrv_co_do_write_zeroes(bs, sector_num, nb_sectors, flags);
f08f2dda
SH
2857 } else {
2858 ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov);
2859 }
6b7cb247 2860
f05fa4ad
PB
2861 if (ret == 0 && !bs->enable_write_cache) {
2862 ret = bdrv_co_flush(bs);
2863 }
2864
e4654d2d 2865 bdrv_set_dirty(bs, sector_num, nb_sectors);
da1fa91d
KW
2866
2867 if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
2868 bs->wr_highest_sector = sector_num + nb_sectors - 1;
2869 }
df2a6f29
PB
2870 if (bs->growable && ret >= 0) {
2871 bs->total_sectors = MAX(bs->total_sectors, sector_num + nb_sectors);
2872 }
da1fa91d 2873
dbffbdcf
SH
2874 tracked_request_end(&req);
2875
6b7cb247 2876 return ret;
da1fa91d
KW
2877}
2878
c5fbe571
SH
2879int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,
2880 int nb_sectors, QEMUIOVector *qiov)
2881{
2882 trace_bdrv_co_writev(bs, sector_num, nb_sectors);
2883
f08f2dda
SH
2884 return bdrv_co_do_writev(bs, sector_num, nb_sectors, qiov, 0);
2885}
2886
2887int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs,
aa7bfbff
PL
2888 int64_t sector_num, int nb_sectors,
2889 BdrvRequestFlags flags)
f08f2dda 2890{
94d6ff21 2891 trace_bdrv_co_write_zeroes(bs, sector_num, nb_sectors, flags);
f08f2dda 2892
d32f35cb
PL
2893 if (!(bs->open_flags & BDRV_O_UNMAP)) {
2894 flags &= ~BDRV_REQ_MAY_UNMAP;
2895 }
2896
f08f2dda 2897 return bdrv_co_do_writev(bs, sector_num, nb_sectors, NULL,
aa7bfbff 2898 BDRV_REQ_ZERO_WRITE | flags);
c5fbe571
SH
2899}
2900
83f64091
FB
2901/**
2902 * Truncate file to 'offset' bytes (needed only for file protocols)
2903 */
2904int bdrv_truncate(BlockDriverState *bs, int64_t offset)
2905{
2906 BlockDriver *drv = bs->drv;
51762288 2907 int ret;
83f64091 2908 if (!drv)
19cb3738 2909 return -ENOMEDIUM;
83f64091
FB
2910 if (!drv->bdrv_truncate)
2911 return -ENOTSUP;
59f2689d
NS
2912 if (bs->read_only)
2913 return -EACCES;
8591675f
MT
2914 if (bdrv_in_use(bs))
2915 return -EBUSY;
51762288
SH
2916 ret = drv->bdrv_truncate(bs, offset);
2917 if (ret == 0) {
2918 ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
145feb17 2919 bdrv_dev_resize_cb(bs);
51762288
SH
2920 }
2921 return ret;
83f64091
FB
2922}
2923
4a1d5e1f
FZ
2924/**
2925 * Length of a allocated file in bytes. Sparse files are counted by actual
2926 * allocated space. Return < 0 if error or unknown.
2927 */
2928int64_t bdrv_get_allocated_file_size(BlockDriverState *bs)
2929{
2930 BlockDriver *drv = bs->drv;
2931 if (!drv) {
2932 return -ENOMEDIUM;
2933 }
2934 if (drv->bdrv_get_allocated_file_size) {
2935 return drv->bdrv_get_allocated_file_size(bs);
2936 }
2937 if (bs->file) {
2938 return bdrv_get_allocated_file_size(bs->file);
2939 }
2940 return -ENOTSUP;
2941}
2942
83f64091
FB
2943/**
2944 * Length of a file in bytes. Return < 0 if error or unknown.
2945 */
2946int64_t bdrv_getlength(BlockDriverState *bs)
2947{
2948 BlockDriver *drv = bs->drv;
2949 if (!drv)
19cb3738 2950 return -ENOMEDIUM;
51762288 2951
b94a2610
KW
2952 if (drv->has_variable_length) {
2953 int ret = refresh_total_sectors(bs, bs->total_sectors);
2954 if (ret < 0) {
2955 return ret;
46a4e4e6 2956 }
83f64091 2957 }
46a4e4e6 2958 return bs->total_sectors * BDRV_SECTOR_SIZE;
fc01f7e7
FB
2959}
2960
19cb3738 2961/* return 0 as number of sectors if no device present or error */
96b8f136 2962void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
fc01f7e7 2963{
19cb3738
FB
2964 int64_t length;
2965 length = bdrv_getlength(bs);
2966 if (length < 0)
2967 length = 0;
2968 else
6ea44308 2969 length = length >> BDRV_SECTOR_BITS;
19cb3738 2970 *nb_sectors_ptr = length;
fc01f7e7 2971}
cf98951b 2972
ff06f5f3
PB
2973void bdrv_set_on_error(BlockDriverState *bs, BlockdevOnError on_read_error,
2974 BlockdevOnError on_write_error)
abd7f68d
MA
2975{
2976 bs->on_read_error = on_read_error;
2977 bs->on_write_error = on_write_error;
2978}
2979
1ceee0d5 2980BlockdevOnError bdrv_get_on_error(BlockDriverState *bs, bool is_read)
abd7f68d
MA
2981{
2982 return is_read ? bs->on_read_error : bs->on_write_error;
2983}
2984
3e1caa5f
PB
2985BlockErrorAction bdrv_get_error_action(BlockDriverState *bs, bool is_read, int error)
2986{
2987 BlockdevOnError on_err = is_read ? bs->on_read_error : bs->on_write_error;
2988
2989 switch (on_err) {
2990 case BLOCKDEV_ON_ERROR_ENOSPC:
2991 return (error == ENOSPC) ? BDRV_ACTION_STOP : BDRV_ACTION_REPORT;
2992 case BLOCKDEV_ON_ERROR_STOP:
2993 return BDRV_ACTION_STOP;
2994 case BLOCKDEV_ON_ERROR_REPORT:
2995 return BDRV_ACTION_REPORT;
2996 case BLOCKDEV_ON_ERROR_IGNORE:
2997 return BDRV_ACTION_IGNORE;
2998 default:
2999 abort();
3000 }
3001}
3002
3003/* This is done by device models because, while the block layer knows
3004 * about the error, it does not know whether an operation comes from
3005 * the device or the block layer (from a job, for example).
3006 */
3007void bdrv_error_action(BlockDriverState *bs, BlockErrorAction action,
3008 bool is_read, int error)
3009{
3010 assert(error >= 0);
32c81a4a 3011 bdrv_emit_qmp_error_event(bs, QEVENT_BLOCK_IO_ERROR, action, is_read);
3e1caa5f
PB
3012 if (action == BDRV_ACTION_STOP) {
3013 vm_stop(RUN_STATE_IO_ERROR);
3014 bdrv_iostatus_set_err(bs, error);
3015 }
3016}
3017
b338082b
FB
3018int bdrv_is_read_only(BlockDriverState *bs)
3019{
3020 return bs->read_only;
3021}
3022
985a03b0
TS
3023int bdrv_is_sg(BlockDriverState *bs)
3024{
3025 return bs->sg;
3026}
3027
e900a7b7
CH
3028int bdrv_enable_write_cache(BlockDriverState *bs)
3029{
3030 return bs->enable_write_cache;
3031}
3032
425b0148
PB
3033void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce)
3034{
3035 bs->enable_write_cache = wce;
55b110f2
JC
3036
3037 /* so a reopen() will preserve wce */
3038 if (wce) {
3039 bs->open_flags |= BDRV_O_CACHE_WB;
3040 } else {
3041 bs->open_flags &= ~BDRV_O_CACHE_WB;
3042 }
425b0148
PB
3043}
3044
ea2384d3
FB
3045int bdrv_is_encrypted(BlockDriverState *bs)
3046{
3047 if (bs->backing_hd && bs->backing_hd->encrypted)
3048 return 1;
3049 return bs->encrypted;
3050}
3051
c0f4ce77
AL
3052int bdrv_key_required(BlockDriverState *bs)
3053{
3054 BlockDriverState *backing_hd = bs->backing_hd;
3055
3056 if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key)
3057 return 1;
3058 return (bs->encrypted && !bs->valid_key);
3059}
3060
ea2384d3
FB
3061int bdrv_set_key(BlockDriverState *bs, const char *key)
3062{
3063 int ret;
3064 if (bs->backing_hd && bs->backing_hd->encrypted) {
3065 ret = bdrv_set_key(bs->backing_hd, key);
3066 if (ret < 0)
3067 return ret;
3068 if (!bs->encrypted)
3069 return 0;
3070 }
fd04a2ae
SH
3071 if (!bs->encrypted) {
3072 return -EINVAL;
3073 } else if (!bs->drv || !bs->drv->bdrv_set_key) {
3074 return -ENOMEDIUM;
3075 }
c0f4ce77 3076 ret = bs->drv->bdrv_set_key(bs, key);
bb5fc20f
AL
3077 if (ret < 0) {
3078 bs->valid_key = 0;
3079 } else if (!bs->valid_key) {
3080 bs->valid_key = 1;
3081 /* call the change callback now, we skipped it on open */
7d4b4ba5 3082 bdrv_dev_change_media_cb(bs, true);
bb5fc20f 3083 }
c0f4ce77 3084 return ret;
ea2384d3
FB
3085}
3086
f8d6bba1 3087const char *bdrv_get_format_name(BlockDriverState *bs)
ea2384d3 3088{
f8d6bba1 3089 return bs->drv ? bs->drv->format_name : NULL;
ea2384d3
FB
3090}
3091
5fafdf24 3092void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
ea2384d3
FB
3093 void *opaque)
3094{
3095 BlockDriver *drv;
3096
8a22f02a 3097 QLIST_FOREACH(drv, &bdrv_drivers, list) {
ea2384d3
FB
3098 it(opaque, drv->format_name);
3099 }
3100}
3101
b338082b
FB
3102BlockDriverState *bdrv_find(const char *name)
3103{
3104 BlockDriverState *bs;
3105
1b7bdbc1
SH
3106 QTAILQ_FOREACH(bs, &bdrv_states, list) {
3107 if (!strcmp(name, bs->device_name)) {
b338082b 3108 return bs;
1b7bdbc1 3109 }
b338082b
FB
3110 }
3111 return NULL;
3112}
3113
2f399b0a
MA
3114BlockDriverState *bdrv_next(BlockDriverState *bs)
3115{
3116 if (!bs) {
3117 return QTAILQ_FIRST(&bdrv_states);
3118 }
3119 return QTAILQ_NEXT(bs, list);
3120}
3121
51de9760 3122void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque)
81d0912d
FB
3123{
3124 BlockDriverState *bs;
3125
1b7bdbc1 3126 QTAILQ_FOREACH(bs, &bdrv_states, list) {
51de9760 3127 it(opaque, bs);
81d0912d
FB
3128 }
3129}
3130
ea2384d3
FB
3131const char *bdrv_get_device_name(BlockDriverState *bs)
3132{
3133 return bs->device_name;
3134}
3135
c8433287
MA
3136int bdrv_get_flags(BlockDriverState *bs)
3137{
3138 return bs->open_flags;
3139}
3140
f0f0fdfe 3141int bdrv_flush_all(void)
c6ca28d6
AL
3142{
3143 BlockDriverState *bs;
f0f0fdfe 3144 int result = 0;
c6ca28d6 3145
1b7bdbc1 3146 QTAILQ_FOREACH(bs, &bdrv_states, list) {
f0f0fdfe
KW
3147 int ret = bdrv_flush(bs);
3148 if (ret < 0 && !result) {
3149 result = ret;
3150 }
1b7bdbc1 3151 }
f0f0fdfe
KW
3152
3153 return result;
c6ca28d6
AL
3154}
3155
3ac21627
PL
3156int bdrv_has_zero_init_1(BlockDriverState *bs)
3157{
3158 return 1;
3159}
3160
f2feebbd
KW
3161int bdrv_has_zero_init(BlockDriverState *bs)
3162{
3163 assert(bs->drv);
3164
11212d8f
PB
3165 /* If BS is a copy on write image, it is initialized to
3166 the contents of the base image, which may not be zeroes. */
3167 if (bs->backing_hd) {
3168 return 0;
3169 }
336c1c12
KW
3170 if (bs->drv->bdrv_has_zero_init) {
3171 return bs->drv->bdrv_has_zero_init(bs);
f2feebbd
KW
3172 }
3173
3ac21627
PL
3174 /* safe default */
3175 return 0;
f2feebbd
KW
3176}
3177
4ce78691
PL
3178bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs)
3179{
3180 BlockDriverInfo bdi;
3181
3182 if (bs->backing_hd) {
3183 return false;
3184 }
3185
3186 if (bdrv_get_info(bs, &bdi) == 0) {
3187 return bdi.unallocated_blocks_are_zero;
3188 }
3189
3190 return false;
3191}
3192
3193bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs)
3194{
3195 BlockDriverInfo bdi;
3196
3197 if (bs->backing_hd || !(bs->open_flags & BDRV_O_UNMAP)) {
3198 return false;
3199 }
3200
3201 if (bdrv_get_info(bs, &bdi) == 0) {
3202 return bdi.can_write_zeroes_with_unmap;
3203 }
3204
3205 return false;
3206}
3207
b6b8a333 3208typedef struct BdrvCoGetBlockStatusData {
376ae3f1 3209 BlockDriverState *bs;
b35b2bba 3210 BlockDriverState *base;
376ae3f1
SH
3211 int64_t sector_num;
3212 int nb_sectors;
3213 int *pnum;
b6b8a333 3214 int64_t ret;
376ae3f1 3215 bool done;
b6b8a333 3216} BdrvCoGetBlockStatusData;
376ae3f1 3217
f58c7b35
TS
3218/*
3219 * Returns true iff the specified sector is present in the disk image. Drivers
3220 * not implementing the functionality are assumed to not support backing files,
3221 * hence all their sectors are reported as allocated.
3222 *
bd9533e3
SH
3223 * If 'sector_num' is beyond the end of the disk image the return value is 0
3224 * and 'pnum' is set to 0.
3225 *
f58c7b35
TS
3226 * 'pnum' is set to the number of sectors (including and immediately following
3227 * the specified sector) that are known to be in the same
3228 * allocated/unallocated state.
3229 *
bd9533e3
SH
3230 * 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes
3231 * beyond the end of the disk image it will be clamped.
f58c7b35 3232 */
b6b8a333
PB
3233static int64_t coroutine_fn bdrv_co_get_block_status(BlockDriverState *bs,
3234 int64_t sector_num,
3235 int nb_sectors, int *pnum)
f58c7b35 3236{
617ccb46 3237 int64_t length;
bd9533e3 3238 int64_t n;
5daa74a6 3239 int64_t ret, ret2;
bd9533e3 3240
617ccb46
PB
3241 length = bdrv_getlength(bs);
3242 if (length < 0) {
3243 return length;
3244 }
3245
3246 if (sector_num >= (length >> BDRV_SECTOR_BITS)) {
bd9533e3
SH
3247 *pnum = 0;
3248 return 0;
3249 }
3250
3251 n = bs->total_sectors - sector_num;
3252 if (n < nb_sectors) {
3253 nb_sectors = n;
3254 }
3255
b6b8a333 3256 if (!bs->drv->bdrv_co_get_block_status) {
bd9533e3 3257 *pnum = nb_sectors;
918e92d7
PB
3258 ret = BDRV_BLOCK_DATA;
3259 if (bs->drv->protocol_name) {
3260 ret |= BDRV_BLOCK_OFFSET_VALID | (sector_num * BDRV_SECTOR_SIZE);
3261 }
3262 return ret;
f58c7b35 3263 }
6aebab14 3264
415b5b01
PB
3265 ret = bs->drv->bdrv_co_get_block_status(bs, sector_num, nb_sectors, pnum);
3266 if (ret < 0) {
3e0a233d 3267 *pnum = 0;
415b5b01
PB
3268 return ret;
3269 }
3270
92bc50a5
PL
3271 if (ret & BDRV_BLOCK_RAW) {
3272 assert(ret & BDRV_BLOCK_OFFSET_VALID);
3273 return bdrv_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS,
3274 *pnum, pnum);
3275 }
3276
c3d86884
PL
3277 if (!(ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO)) {
3278 if (bdrv_unallocated_blocks_are_zero(bs)) {
f0ad5712 3279 ret |= BDRV_BLOCK_ZERO;
1f9db224 3280 } else if (bs->backing_hd) {
f0ad5712
PB
3281 BlockDriverState *bs2 = bs->backing_hd;
3282 int64_t length2 = bdrv_getlength(bs2);
3283 if (length2 >= 0 && sector_num >= (length2 >> BDRV_SECTOR_BITS)) {
3284 ret |= BDRV_BLOCK_ZERO;
3285 }
3286 }
415b5b01 3287 }
5daa74a6
PB
3288
3289 if (bs->file &&
3290 (ret & BDRV_BLOCK_DATA) && !(ret & BDRV_BLOCK_ZERO) &&
3291 (ret & BDRV_BLOCK_OFFSET_VALID)) {
3292 ret2 = bdrv_co_get_block_status(bs->file, ret >> BDRV_SECTOR_BITS,
3293 *pnum, pnum);
3294 if (ret2 >= 0) {
3295 /* Ignore errors. This is just providing extra information, it
3296 * is useful but not necessary.
3297 */
3298 ret |= (ret2 & BDRV_BLOCK_ZERO);
3299 }
3300 }
3301
415b5b01 3302 return ret;
060f51c9
SH
3303}
3304
b6b8a333
PB
3305/* Coroutine wrapper for bdrv_get_block_status() */
3306static void coroutine_fn bdrv_get_block_status_co_entry(void *opaque)
060f51c9 3307{
b6b8a333 3308 BdrvCoGetBlockStatusData *data = opaque;
060f51c9
SH
3309 BlockDriverState *bs = data->bs;
3310
b6b8a333
PB
3311 data->ret = bdrv_co_get_block_status(bs, data->sector_num, data->nb_sectors,
3312 data->pnum);
060f51c9
SH
3313 data->done = true;
3314}
3315
3316/*
b6b8a333 3317 * Synchronous wrapper around bdrv_co_get_block_status().
060f51c9 3318 *
b6b8a333 3319 * See bdrv_co_get_block_status() for details.
060f51c9 3320 */
b6b8a333
PB
3321int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num,
3322 int nb_sectors, int *pnum)
060f51c9 3323{
6aebab14 3324 Coroutine *co;
b6b8a333 3325 BdrvCoGetBlockStatusData data = {
6aebab14
SH
3326 .bs = bs,
3327 .sector_num = sector_num,
3328 .nb_sectors = nb_sectors,
3329 .pnum = pnum,
3330 .done = false,
3331 };
3332
bdad13b9
PB
3333 if (qemu_in_coroutine()) {
3334 /* Fast-path if already in coroutine context */
b6b8a333 3335 bdrv_get_block_status_co_entry(&data);
bdad13b9 3336 } else {
b6b8a333 3337 co = qemu_coroutine_create(bdrv_get_block_status_co_entry);
bdad13b9
PB
3338 qemu_coroutine_enter(co, &data);
3339 while (!data.done) {
3340 qemu_aio_wait();
3341 }
6aebab14
SH
3342 }
3343 return data.ret;
f58c7b35
TS
3344}
3345
b6b8a333
PB
3346int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num,
3347 int nb_sectors, int *pnum)
3348{
4333bb71
PB
3349 int64_t ret = bdrv_get_block_status(bs, sector_num, nb_sectors, pnum);
3350 if (ret < 0) {
3351 return ret;
3352 }
3353 return
3354 (ret & BDRV_BLOCK_DATA) ||
3355 ((ret & BDRV_BLOCK_ZERO) && !bdrv_has_zero_init(bs));
b6b8a333
PB
3356}
3357
188a7bbf
PB
3358/*
3359 * Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP]
3360 *
3361 * Return true if the given sector is allocated in any image between
3362 * BASE and TOP (inclusive). BASE can be NULL to check if the given
3363 * sector is allocated in any image of the chain. Return false otherwise.
3364 *
3365 * 'pnum' is set to the number of sectors (including and immediately following
3366 * the specified sector) that are known to be in the same
3367 * allocated/unallocated state.
3368 *
3369 */
4f578637
PB
3370int bdrv_is_allocated_above(BlockDriverState *top,
3371 BlockDriverState *base,
3372 int64_t sector_num,
3373 int nb_sectors, int *pnum)
188a7bbf
PB
3374{
3375 BlockDriverState *intermediate;
3376 int ret, n = nb_sectors;
3377
3378 intermediate = top;
3379 while (intermediate && intermediate != base) {
3380 int pnum_inter;
bdad13b9
PB
3381 ret = bdrv_is_allocated(intermediate, sector_num, nb_sectors,
3382 &pnum_inter);
188a7bbf
PB
3383 if (ret < 0) {
3384 return ret;
3385 } else if (ret) {
3386 *pnum = pnum_inter;
3387 return 1;
3388 }
3389
3390 /*
3391 * [sector_num, nb_sectors] is unallocated on top but intermediate
3392 * might have
3393 *
3394 * [sector_num+x, nr_sectors] allocated.
3395 */
63ba17d3
VI
3396 if (n > pnum_inter &&
3397 (intermediate == top ||
3398 sector_num + pnum_inter < intermediate->total_sectors)) {
188a7bbf
PB
3399 n = pnum_inter;
3400 }
3401
3402 intermediate = intermediate->backing_hd;
3403 }
3404
3405 *pnum = n;
3406 return 0;
3407}
3408
045df330
AL
3409const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
3410{
3411 if (bs->backing_hd && bs->backing_hd->encrypted)
3412 return bs->backing_file;
3413 else if (bs->encrypted)
3414 return bs->filename;
3415 else
3416 return NULL;
3417}
3418
5fafdf24 3419void bdrv_get_backing_filename(BlockDriverState *bs,
83f64091
FB
3420 char *filename, int filename_size)
3421{
3574c608 3422 pstrcpy(filename, filename_size, bs->backing_file);
83f64091
FB
3423}
3424
5fafdf24 3425int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
faea38e7
FB
3426 const uint8_t *buf, int nb_sectors)
3427{
3428 BlockDriver *drv = bs->drv;
3429 if (!drv)
19cb3738 3430 return -ENOMEDIUM;
faea38e7
FB
3431 if (!drv->bdrv_write_compressed)
3432 return -ENOTSUP;
fbb7b4e0
KW
3433 if (bdrv_check_request(bs, sector_num, nb_sectors))
3434 return -EIO;
a55eb92c 3435
e4654d2d 3436 assert(QLIST_EMPTY(&bs->dirty_bitmaps));
a55eb92c 3437
faea38e7
FB
3438 return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
3439}
3b46e624 3440
faea38e7
FB
3441int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
3442{
3443 BlockDriver *drv = bs->drv;
3444 if (!drv)
19cb3738 3445 return -ENOMEDIUM;
faea38e7
FB
3446 if (!drv->bdrv_get_info)
3447 return -ENOTSUP;
3448 memset(bdi, 0, sizeof(*bdi));
3449 return drv->bdrv_get_info(bs, bdi);
3450}
3451
eae041fe
HR
3452ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs)
3453{
3454 BlockDriver *drv = bs->drv;
3455 if (drv && drv->bdrv_get_specific_info) {
3456 return drv->bdrv_get_specific_info(bs);
3457 }
3458 return NULL;
3459}
3460
45566e9c
CH
3461int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
3462 int64_t pos, int size)
cf8074b3
KW
3463{
3464 QEMUIOVector qiov;
3465 struct iovec iov = {
3466 .iov_base = (void *) buf,
3467 .iov_len = size,
3468 };
3469
3470 qemu_iovec_init_external(&qiov, &iov, 1);
3471 return bdrv_writev_vmstate(bs, &qiov, pos);
3472}
3473
3474int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos)
178e08a5
AL
3475{
3476 BlockDriver *drv = bs->drv;
cf8074b3
KW
3477
3478 if (!drv) {
178e08a5 3479 return -ENOMEDIUM;
cf8074b3
KW
3480 } else if (drv->bdrv_save_vmstate) {
3481 return drv->bdrv_save_vmstate(bs, qiov, pos);
3482 } else if (bs->file) {
3483 return bdrv_writev_vmstate(bs->file, qiov, pos);
3484 }
3485
7cdb1f6d 3486 return -ENOTSUP;
178e08a5
AL
3487}
3488
45566e9c
CH
3489int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
3490 int64_t pos, int size)
178e08a5
AL
3491{
3492 BlockDriver *drv = bs->drv;
3493 if (!drv)
3494 return -ENOMEDIUM;
7cdb1f6d
MK
3495 if (drv->bdrv_load_vmstate)
3496 return drv->bdrv_load_vmstate(bs, buf, pos, size);
3497 if (bs->file)
3498 return bdrv_load_vmstate(bs->file, buf, pos, size);
3499 return -ENOTSUP;
178e08a5
AL
3500}
3501
8b9b0cc2
KW
3502void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event)
3503{
bf736fe3 3504 if (!bs || !bs->drv || !bs->drv->bdrv_debug_event) {
8b9b0cc2
KW
3505 return;
3506 }
3507
bf736fe3 3508 bs->drv->bdrv_debug_event(bs, event);
41c695c7
KW
3509}
3510
3511int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
3512 const char *tag)
3513{
3514 while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) {
3515 bs = bs->file;
3516 }
3517
3518 if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) {
3519 return bs->drv->bdrv_debug_breakpoint(bs, event, tag);
3520 }
3521
3522 return -ENOTSUP;
3523}
3524
4cc70e93
FZ
3525int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag)
3526{
3527 while (bs && bs->drv && !bs->drv->bdrv_debug_remove_breakpoint) {
3528 bs = bs->file;
3529 }
3530
3531 if (bs && bs->drv && bs->drv->bdrv_debug_remove_breakpoint) {
3532 return bs->drv->bdrv_debug_remove_breakpoint(bs, tag);
3533 }
3534
3535 return -ENOTSUP;
3536}
3537
41c695c7
KW
3538int bdrv_debug_resume(BlockDriverState *bs, const char *tag)
3539{
3540 while (bs && bs->drv && !bs->drv->bdrv_debug_resume) {
3541 bs = bs->file;
3542 }
8b9b0cc2 3543
41c695c7
KW
3544 if (bs && bs->drv && bs->drv->bdrv_debug_resume) {
3545 return bs->drv->bdrv_debug_resume(bs, tag);
3546 }
3547
3548 return -ENOTSUP;
3549}
3550
3551bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag)
3552{
3553 while (bs && bs->drv && !bs->drv->bdrv_debug_is_suspended) {
3554 bs = bs->file;
3555 }
3556
3557 if (bs && bs->drv && bs->drv->bdrv_debug_is_suspended) {
3558 return bs->drv->bdrv_debug_is_suspended(bs, tag);
3559 }
3560
3561 return false;
8b9b0cc2
KW
3562}
3563
199630b6
BS
3564int bdrv_is_snapshot(BlockDriverState *bs)
3565{
3566 return !!(bs->open_flags & BDRV_O_SNAPSHOT);
3567}
3568
b1b1d783
JC
3569/* backing_file can either be relative, or absolute, or a protocol. If it is
3570 * relative, it must be relative to the chain. So, passing in bs->filename
3571 * from a BDS as backing_file should not be done, as that may be relative to
3572 * the CWD rather than the chain. */
e8a6bb9c
MT
3573BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
3574 const char *backing_file)
3575{
b1b1d783
JC
3576 char *filename_full = NULL;
3577 char *backing_file_full = NULL;
3578 char *filename_tmp = NULL;
3579 int is_protocol = 0;
3580 BlockDriverState *curr_bs = NULL;
3581 BlockDriverState *retval = NULL;
3582
3583 if (!bs || !bs->drv || !backing_file) {
e8a6bb9c
MT
3584 return NULL;
3585 }
3586
b1b1d783
JC
3587 filename_full = g_malloc(PATH_MAX);
3588 backing_file_full = g_malloc(PATH_MAX);
3589 filename_tmp = g_malloc(PATH_MAX);
3590
3591 is_protocol = path_has_protocol(backing_file);
3592
3593 for (curr_bs = bs; curr_bs->backing_hd; curr_bs = curr_bs->backing_hd) {
3594
3595 /* If either of the filename paths is actually a protocol, then
3596 * compare unmodified paths; otherwise make paths relative */
3597 if (is_protocol || path_has_protocol(curr_bs->backing_file)) {
3598 if (strcmp(backing_file, curr_bs->backing_file) == 0) {
3599 retval = curr_bs->backing_hd;
3600 break;
3601 }
e8a6bb9c 3602 } else {
b1b1d783
JC
3603 /* If not an absolute filename path, make it relative to the current
3604 * image's filename path */
3605 path_combine(filename_tmp, PATH_MAX, curr_bs->filename,
3606 backing_file);
3607
3608 /* We are going to compare absolute pathnames */
3609 if (!realpath(filename_tmp, filename_full)) {
3610 continue;
3611 }
3612
3613 /* We need to make sure the backing filename we are comparing against
3614 * is relative to the current image filename (or absolute) */
3615 path_combine(filename_tmp, PATH_MAX, curr_bs->filename,
3616 curr_bs->backing_file);
3617
3618 if (!realpath(filename_tmp, backing_file_full)) {
3619 continue;
3620 }
3621
3622 if (strcmp(backing_file_full, filename_full) == 0) {
3623 retval = curr_bs->backing_hd;
3624 break;
3625 }
e8a6bb9c
MT
3626 }
3627 }
3628
b1b1d783
JC
3629 g_free(filename_full);
3630 g_free(backing_file_full);
3631 g_free(filename_tmp);
3632 return retval;
e8a6bb9c
MT
3633}
3634
f198fd1c
BC
3635int bdrv_get_backing_file_depth(BlockDriverState *bs)
3636{
3637 if (!bs->drv) {
3638 return 0;
3639 }
3640
3641 if (!bs->backing_hd) {
3642 return 0;
3643 }
3644
3645 return 1 + bdrv_get_backing_file_depth(bs->backing_hd);
3646}
3647
79fac568
JC
3648BlockDriverState *bdrv_find_base(BlockDriverState *bs)
3649{
3650 BlockDriverState *curr_bs = NULL;
3651
3652 if (!bs) {
3653 return NULL;
3654 }
3655
3656 curr_bs = bs;
3657
3658 while (curr_bs->backing_hd) {
3659 curr_bs = curr_bs->backing_hd;
3660 }
3661 return curr_bs;
3662}
3663
ea2384d3 3664/**************************************************************/
83f64091 3665/* async I/Os */
ea2384d3 3666
3b69e4b9 3667BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
f141eafe 3668 QEMUIOVector *qiov, int nb_sectors,
3b69e4b9 3669 BlockDriverCompletionFunc *cb, void *opaque)
83f64091 3670{
bbf0a440
SH
3671 trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque);
3672
d20d9b7c 3673 return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0,
8c5873d6 3674 cb, opaque, false);
ea2384d3
FB
3675}
3676
f141eafe
AL
3677BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
3678 QEMUIOVector *qiov, int nb_sectors,
3679 BlockDriverCompletionFunc *cb, void *opaque)
ea2384d3 3680{
bbf0a440
SH
3681 trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque);
3682
d20d9b7c 3683 return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors, 0,
8c5873d6 3684 cb, opaque, true);
83f64091
FB
3685}
3686
40b4f539
KW
3687
3688typedef struct MultiwriteCB {
3689 int error;
3690 int num_requests;
3691 int num_callbacks;
3692 struct {
3693 BlockDriverCompletionFunc *cb;
3694 void *opaque;
3695 QEMUIOVector *free_qiov;
40b4f539
KW
3696 } callbacks[];
3697} MultiwriteCB;
3698
3699static void multiwrite_user_cb(MultiwriteCB *mcb)
3700{
3701 int i;
3702
3703 for (i = 0; i < mcb->num_callbacks; i++) {
3704 mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error);
1e1ea48d
SH
3705 if (mcb->callbacks[i].free_qiov) {
3706 qemu_iovec_destroy(mcb->callbacks[i].free_qiov);
3707 }
7267c094 3708 g_free(mcb->callbacks[i].free_qiov);
40b4f539
KW
3709 }
3710}
3711
3712static void multiwrite_cb(void *opaque, int ret)
3713{
3714 MultiwriteCB *mcb = opaque;
3715
6d519a5f
SH
3716 trace_multiwrite_cb(mcb, ret);
3717
cb6d3ca0 3718 if (ret < 0 && !mcb->error) {
40b4f539 3719 mcb->error = ret;
40b4f539
KW
3720 }
3721
3722 mcb->num_requests--;
3723 if (mcb->num_requests == 0) {
de189a1b 3724 multiwrite_user_cb(mcb);
7267c094 3725 g_free(mcb);
40b4f539
KW
3726 }
3727}
3728
3729static int multiwrite_req_compare(const void *a, const void *b)
3730{
77be4366
CH
3731 const BlockRequest *req1 = a, *req2 = b;
3732
3733 /*
3734 * Note that we can't simply subtract req2->sector from req1->sector
3735 * here as that could overflow the return value.
3736 */
3737 if (req1->sector > req2->sector) {
3738 return 1;
3739 } else if (req1->sector < req2->sector) {
3740 return -1;
3741 } else {
3742 return 0;
3743 }
40b4f539
KW
3744}
3745
3746/*
3747 * Takes a bunch of requests and tries to merge them. Returns the number of
3748 * requests that remain after merging.
3749 */
3750static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs,
3751 int num_reqs, MultiwriteCB *mcb)
3752{
3753 int i, outidx;
3754
3755 // Sort requests by start sector
3756 qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare);
3757
3758 // Check if adjacent requests touch the same clusters. If so, combine them,
3759 // filling up gaps with zero sectors.
3760 outidx = 0;
3761 for (i = 1; i < num_reqs; i++) {
3762 int merge = 0;
3763 int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors;
3764
b6a127a1 3765 // Handle exactly sequential writes and overlapping writes.
40b4f539
KW
3766 if (reqs[i].sector <= oldreq_last) {
3767 merge = 1;
3768 }
3769
e2a305fb
CH
3770 if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) {
3771 merge = 0;
3772 }
3773
40b4f539
KW
3774 if (merge) {
3775 size_t size;
7267c094 3776 QEMUIOVector *qiov = g_malloc0(sizeof(*qiov));
40b4f539
KW
3777 qemu_iovec_init(qiov,
3778 reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1);
3779
3780 // Add the first request to the merged one. If the requests are
3781 // overlapping, drop the last sectors of the first request.
3782 size = (reqs[i].sector - reqs[outidx].sector) << 9;
1b093c48 3783 qemu_iovec_concat(qiov, reqs[outidx].qiov, 0, size);
40b4f539 3784
b6a127a1
PB
3785 // We should need to add any zeros between the two requests
3786 assert (reqs[i].sector <= oldreq_last);
40b4f539
KW
3787
3788 // Add the second request
1b093c48 3789 qemu_iovec_concat(qiov, reqs[i].qiov, 0, reqs[i].qiov->size);
40b4f539 3790
cbf1dff2 3791 reqs[outidx].nb_sectors = qiov->size >> 9;
40b4f539
KW
3792 reqs[outidx].qiov = qiov;
3793
3794 mcb->callbacks[i].free_qiov = reqs[outidx].qiov;
3795 } else {
3796 outidx++;
3797 reqs[outidx].sector = reqs[i].sector;
3798 reqs[outidx].nb_sectors = reqs[i].nb_sectors;
3799 reqs[outidx].qiov = reqs[i].qiov;
3800 }
3801 }
3802
3803 return outidx + 1;
3804}
3805
3806/*
3807 * Submit multiple AIO write requests at once.
3808 *
3809 * On success, the function returns 0 and all requests in the reqs array have
3810 * been submitted. In error case this function returns -1, and any of the
3811 * requests may or may not be submitted yet. In particular, this means that the
3812 * callback will be called for some of the requests, for others it won't. The
3813 * caller must check the error field of the BlockRequest to wait for the right
3814 * callbacks (if error != 0, no callback will be called).
3815 *
3816 * The implementation may modify the contents of the reqs array, e.g. to merge
3817 * requests. However, the fields opaque and error are left unmodified as they
3818 * are used to signal failure for a single request to the caller.
3819 */
3820int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs)
3821{
40b4f539
KW
3822 MultiwriteCB *mcb;
3823 int i;
3824
301db7c2
RH
3825 /* don't submit writes if we don't have a medium */
3826 if (bs->drv == NULL) {
3827 for (i = 0; i < num_reqs; i++) {
3828 reqs[i].error = -ENOMEDIUM;
3829 }
3830 return -1;
3831 }
3832
40b4f539
KW
3833 if (num_reqs == 0) {
3834 return 0;
3835 }
3836
3837 // Create MultiwriteCB structure
7267c094 3838 mcb = g_malloc0(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks));
40b4f539
KW
3839 mcb->num_requests = 0;
3840 mcb->num_callbacks = num_reqs;
3841
3842 for (i = 0; i < num_reqs; i++) {
3843 mcb->callbacks[i].cb = reqs[i].cb;
3844 mcb->callbacks[i].opaque = reqs[i].opaque;
3845 }
3846
3847 // Check for mergable requests
3848 num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb);
3849
6d519a5f
SH
3850 trace_bdrv_aio_multiwrite(mcb, mcb->num_callbacks, num_reqs);
3851
df9309fb
PB
3852 /* Run the aio requests. */
3853 mcb->num_requests = num_reqs;
40b4f539 3854 for (i = 0; i < num_reqs; i++) {
d20d9b7c
PB
3855 bdrv_co_aio_rw_vector(bs, reqs[i].sector, reqs[i].qiov,
3856 reqs[i].nb_sectors, reqs[i].flags,
3857 multiwrite_cb, mcb,
3858 true);
40b4f539
KW
3859 }
3860
3861 return 0;
40b4f539
KW
3862}
3863
83f64091 3864void bdrv_aio_cancel(BlockDriverAIOCB *acb)
83f64091 3865{
d7331bed 3866 acb->aiocb_info->cancel(acb);
83f64091
FB
3867}
3868
3869/**************************************************************/
3870/* async block device emulation */
3871
c16b5a2c
CH
3872typedef struct BlockDriverAIOCBSync {
3873 BlockDriverAIOCB common;
3874 QEMUBH *bh;
3875 int ret;
3876 /* vector translation state */
3877 QEMUIOVector *qiov;
3878 uint8_t *bounce;
3879 int is_write;
3880} BlockDriverAIOCBSync;
3881
3882static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
3883{
b666d239
KW
3884 BlockDriverAIOCBSync *acb =
3885 container_of(blockacb, BlockDriverAIOCBSync, common);
6a7ad299 3886 qemu_bh_delete(acb->bh);
36afc451 3887 acb->bh = NULL;
c16b5a2c
CH
3888 qemu_aio_release(acb);
3889}
3890
d7331bed 3891static const AIOCBInfo bdrv_em_aiocb_info = {
c16b5a2c
CH
3892 .aiocb_size = sizeof(BlockDriverAIOCBSync),
3893 .cancel = bdrv_aio_cancel_em,
3894};
3895
ce1a14dc 3896static void bdrv_aio_bh_cb(void *opaque)
83f64091 3897{
ce1a14dc 3898 BlockDriverAIOCBSync *acb = opaque;
f141eafe 3899
f141eafe 3900 if (!acb->is_write)
03396148 3901 qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size);
ceb42de8 3902 qemu_vfree(acb->bounce);
ce1a14dc 3903 acb->common.cb(acb->common.opaque, acb->ret);
6a7ad299 3904 qemu_bh_delete(acb->bh);
36afc451 3905 acb->bh = NULL;
ce1a14dc 3906 qemu_aio_release(acb);
83f64091 3907}
beac80cd 3908
f141eafe
AL
3909static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs,
3910 int64_t sector_num,
3911 QEMUIOVector *qiov,
3912 int nb_sectors,
3913 BlockDriverCompletionFunc *cb,
3914 void *opaque,
3915 int is_write)
3916
83f64091 3917{
ce1a14dc 3918 BlockDriverAIOCBSync *acb;
ce1a14dc 3919
d7331bed 3920 acb = qemu_aio_get(&bdrv_em_aiocb_info, bs, cb, opaque);
f141eafe
AL
3921 acb->is_write = is_write;
3922 acb->qiov = qiov;
e268ca52 3923 acb->bounce = qemu_blockalign(bs, qiov->size);
3f3aace8 3924 acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
f141eafe
AL
3925
3926 if (is_write) {
d5e6b161 3927 qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size);
1ed20acf 3928 acb->ret = bs->drv->bdrv_write(bs, sector_num, acb->bounce, nb_sectors);
f141eafe 3929 } else {
1ed20acf 3930 acb->ret = bs->drv->bdrv_read(bs, sector_num, acb->bounce, nb_sectors);
f141eafe
AL
3931 }
3932
ce1a14dc 3933 qemu_bh_schedule(acb->bh);
f141eafe 3934
ce1a14dc 3935 return &acb->common;
beac80cd
FB
3936}
3937
f141eafe
AL
3938static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
3939 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
ce1a14dc 3940 BlockDriverCompletionFunc *cb, void *opaque)
beac80cd 3941{
f141eafe
AL
3942 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
3943}
83f64091 3944
f141eafe
AL
3945static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
3946 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
3947 BlockDriverCompletionFunc *cb, void *opaque)
3948{
3949 return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
beac80cd 3950}
beac80cd 3951
68485420
KW
3952
3953typedef struct BlockDriverAIOCBCoroutine {
3954 BlockDriverAIOCB common;
3955 BlockRequest req;
3956 bool is_write;
d318aea9 3957 bool *done;
68485420
KW
3958 QEMUBH* bh;
3959} BlockDriverAIOCBCoroutine;
3960
3961static void bdrv_aio_co_cancel_em(BlockDriverAIOCB *blockacb)
3962{
d318aea9
KW
3963 BlockDriverAIOCBCoroutine *acb =
3964 container_of(blockacb, BlockDriverAIOCBCoroutine, common);
3965 bool done = false;
3966
3967 acb->done = &done;
3968 while (!done) {
3969 qemu_aio_wait();
3970 }
68485420
KW
3971}
3972
d7331bed 3973static const AIOCBInfo bdrv_em_co_aiocb_info = {
68485420
KW
3974 .aiocb_size = sizeof(BlockDriverAIOCBCoroutine),
3975 .cancel = bdrv_aio_co_cancel_em,
3976};
3977
35246a68 3978static void bdrv_co_em_bh(void *opaque)
68485420
KW
3979{
3980 BlockDriverAIOCBCoroutine *acb = opaque;
3981
3982 acb->common.cb(acb->common.opaque, acb->req.error);
d318aea9
KW
3983
3984 if (acb->done) {
3985 *acb->done = true;
3986 }
3987
68485420
KW
3988 qemu_bh_delete(acb->bh);
3989 qemu_aio_release(acb);
3990}
3991
b2a61371
SH
3992/* Invoke bdrv_co_do_readv/bdrv_co_do_writev */
3993static void coroutine_fn bdrv_co_do_rw(void *opaque)
3994{
3995 BlockDriverAIOCBCoroutine *acb = opaque;
3996 BlockDriverState *bs = acb->common.bs;
3997
3998 if (!acb->is_write) {
3999 acb->req.error = bdrv_co_do_readv(bs, acb->req.sector,
d20d9b7c 4000 acb->req.nb_sectors, acb->req.qiov, acb->req.flags);
b2a61371
SH
4001 } else {
4002 acb->req.error = bdrv_co_do_writev(bs, acb->req.sector,
d20d9b7c 4003 acb->req.nb_sectors, acb->req.qiov, acb->req.flags);
b2a61371
SH
4004 }
4005
35246a68 4006 acb->bh = qemu_bh_new(bdrv_co_em_bh, acb);
b2a61371
SH
4007 qemu_bh_schedule(acb->bh);
4008}
4009
68485420
KW
4010static BlockDriverAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
4011 int64_t sector_num,
4012 QEMUIOVector *qiov,
4013 int nb_sectors,
d20d9b7c 4014 BdrvRequestFlags flags,
68485420
KW
4015 BlockDriverCompletionFunc *cb,
4016 void *opaque,
8c5873d6 4017 bool is_write)
68485420
KW
4018{
4019 Coroutine *co;
4020 BlockDriverAIOCBCoroutine *acb;
4021
d7331bed 4022 acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque);
68485420
KW
4023 acb->req.sector = sector_num;
4024 acb->req.nb_sectors = nb_sectors;
4025 acb->req.qiov = qiov;
d20d9b7c 4026 acb->req.flags = flags;
68485420 4027 acb->is_write = is_write;
d318aea9 4028 acb->done = NULL;
68485420 4029
8c5873d6 4030 co = qemu_coroutine_create(bdrv_co_do_rw);
68485420
KW
4031 qemu_coroutine_enter(co, acb);
4032
4033 return &acb->common;
4034}
4035
07f07615 4036static void coroutine_fn bdrv_aio_flush_co_entry(void *opaque)
b2e12bc6 4037{
07f07615
PB
4038 BlockDriverAIOCBCoroutine *acb = opaque;
4039 BlockDriverState *bs = acb->common.bs;
b2e12bc6 4040
07f07615
PB
4041 acb->req.error = bdrv_co_flush(bs);
4042 acb->bh = qemu_bh_new(bdrv_co_em_bh, acb);
b2e12bc6 4043 qemu_bh_schedule(acb->bh);
b2e12bc6
CH
4044}
4045
07f07615 4046BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
016f5cf6
AG
4047 BlockDriverCompletionFunc *cb, void *opaque)
4048{
07f07615 4049 trace_bdrv_aio_flush(bs, opaque);
016f5cf6 4050
07f07615
PB
4051 Coroutine *co;
4052 BlockDriverAIOCBCoroutine *acb;
016f5cf6 4053
d7331bed 4054 acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque);
d318aea9
KW
4055 acb->done = NULL;
4056
07f07615
PB
4057 co = qemu_coroutine_create(bdrv_aio_flush_co_entry);
4058 qemu_coroutine_enter(co, acb);
016f5cf6 4059
016f5cf6
AG
4060 return &acb->common;
4061}
4062
4265d620
PB
4063static void coroutine_fn bdrv_aio_discard_co_entry(void *opaque)
4064{
4065 BlockDriverAIOCBCoroutine *acb = opaque;
4066 BlockDriverState *bs = acb->common.bs;
4067
4068 acb->req.error = bdrv_co_discard(bs, acb->req.sector, acb->req.nb_sectors);
4069 acb->bh = qemu_bh_new(bdrv_co_em_bh, acb);
4070 qemu_bh_schedule(acb->bh);
4071}
4072
4073BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs,
4074 int64_t sector_num, int nb_sectors,
4075 BlockDriverCompletionFunc *cb, void *opaque)
4076{
4077 Coroutine *co;
4078 BlockDriverAIOCBCoroutine *acb;
4079
4080 trace_bdrv_aio_discard(bs, sector_num, nb_sectors, opaque);
4081
d7331bed 4082 acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque);
4265d620
PB
4083 acb->req.sector = sector_num;
4084 acb->req.nb_sectors = nb_sectors;
d318aea9 4085 acb->done = NULL;
4265d620
PB
4086 co = qemu_coroutine_create(bdrv_aio_discard_co_entry);
4087 qemu_coroutine_enter(co, acb);
4088
4089 return &acb->common;
4090}
4091
ea2384d3
FB
4092void bdrv_init(void)
4093{
5efa9d5a 4094 module_call_init(MODULE_INIT_BLOCK);
ea2384d3 4095}
ce1a14dc 4096
eb852011
MA
4097void bdrv_init_with_whitelist(void)
4098{
4099 use_bdrv_whitelist = 1;
4100 bdrv_init();
4101}
4102
d7331bed 4103void *qemu_aio_get(const AIOCBInfo *aiocb_info, BlockDriverState *bs,
c16b5a2c 4104 BlockDriverCompletionFunc *cb, void *opaque)
ce1a14dc 4105{
ce1a14dc
PB
4106 BlockDriverAIOCB *acb;
4107
d7331bed
SH
4108 acb = g_slice_alloc(aiocb_info->aiocb_size);
4109 acb->aiocb_info = aiocb_info;
ce1a14dc
PB
4110 acb->bs = bs;
4111 acb->cb = cb;
4112 acb->opaque = opaque;
4113 return acb;
4114}
4115
4116void qemu_aio_release(void *p)
4117{
d37c975f 4118 BlockDriverAIOCB *acb = p;
d7331bed 4119 g_slice_free1(acb->aiocb_info->aiocb_size, acb);
ce1a14dc 4120}
19cb3738 4121
f9f05dc5
KW
4122/**************************************************************/
4123/* Coroutine block device emulation */
4124
4125typedef struct CoroutineIOCompletion {
4126 Coroutine *coroutine;
4127 int ret;
4128} CoroutineIOCompletion;
4129
4130static void bdrv_co_io_em_complete(void *opaque, int ret)
4131{
4132 CoroutineIOCompletion *co = opaque;
4133
4134 co->ret = ret;
4135 qemu_coroutine_enter(co->coroutine, NULL);
4136}
4137
4138static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num,
4139 int nb_sectors, QEMUIOVector *iov,
4140 bool is_write)
4141{
4142 CoroutineIOCompletion co = {
4143 .coroutine = qemu_coroutine_self(),
4144 };
4145 BlockDriverAIOCB *acb;
4146
4147 if (is_write) {
a652d160
SH
4148 acb = bs->drv->bdrv_aio_writev(bs, sector_num, iov, nb_sectors,
4149 bdrv_co_io_em_complete, &co);
f9f05dc5 4150 } else {
a652d160
SH
4151 acb = bs->drv->bdrv_aio_readv(bs, sector_num, iov, nb_sectors,
4152 bdrv_co_io_em_complete, &co);
f9f05dc5
KW
4153 }
4154
59370aaa 4155 trace_bdrv_co_io_em(bs, sector_num, nb_sectors, is_write, acb);
f9f05dc5
KW
4156 if (!acb) {
4157 return -EIO;
4158 }
4159 qemu_coroutine_yield();
4160
4161 return co.ret;
4162}
4163
4164static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
4165 int64_t sector_num, int nb_sectors,
4166 QEMUIOVector *iov)
4167{
4168 return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false);
4169}
4170
4171static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
4172 int64_t sector_num, int nb_sectors,
4173 QEMUIOVector *iov)
4174{
4175 return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true);
4176}
4177
07f07615 4178static void coroutine_fn bdrv_flush_co_entry(void *opaque)
e7a8a783 4179{
07f07615
PB
4180 RwCo *rwco = opaque;
4181
4182 rwco->ret = bdrv_co_flush(rwco->bs);
4183}
4184
4185int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
4186{
eb489bb1
KW
4187 int ret;
4188
29cdb251 4189 if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
07f07615 4190 return 0;
eb489bb1
KW
4191 }
4192
ca716364 4193 /* Write back cached data to the OS even with cache=unsafe */
bf736fe3 4194 BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS);
eb489bb1
KW
4195 if (bs->drv->bdrv_co_flush_to_os) {
4196 ret = bs->drv->bdrv_co_flush_to_os(bs);
4197 if (ret < 0) {
4198 return ret;
4199 }
4200 }
4201
ca716364
KW
4202 /* But don't actually force it to the disk with cache=unsafe */
4203 if (bs->open_flags & BDRV_O_NO_FLUSH) {
d4c82329 4204 goto flush_parent;
ca716364
KW
4205 }
4206
bf736fe3 4207 BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_DISK);
eb489bb1 4208 if (bs->drv->bdrv_co_flush_to_disk) {
29cdb251 4209 ret = bs->drv->bdrv_co_flush_to_disk(bs);
07f07615
PB
4210 } else if (bs->drv->bdrv_aio_flush) {
4211 BlockDriverAIOCB *acb;
4212 CoroutineIOCompletion co = {
4213 .coroutine = qemu_coroutine_self(),
4214 };
4215
4216 acb = bs->drv->bdrv_aio_flush(bs, bdrv_co_io_em_complete, &co);
4217 if (acb == NULL) {
29cdb251 4218 ret = -EIO;
07f07615
PB
4219 } else {
4220 qemu_coroutine_yield();
29cdb251 4221 ret = co.ret;
07f07615 4222 }
07f07615
PB
4223 } else {
4224 /*
4225 * Some block drivers always operate in either writethrough or unsafe
4226 * mode and don't support bdrv_flush therefore. Usually qemu doesn't
4227 * know how the server works (because the behaviour is hardcoded or
4228 * depends on server-side configuration), so we can't ensure that
4229 * everything is safe on disk. Returning an error doesn't work because
4230 * that would break guests even if the server operates in writethrough
4231 * mode.
4232 *
4233 * Let's hope the user knows what he's doing.
4234 */
29cdb251 4235 ret = 0;
07f07615 4236 }
29cdb251
PB
4237 if (ret < 0) {
4238 return ret;
4239 }
4240
4241 /* Now flush the underlying protocol. It will also have BDRV_O_NO_FLUSH
4242 * in the case of cache=unsafe, so there are no useless flushes.
4243 */
d4c82329 4244flush_parent:
29cdb251 4245 return bdrv_co_flush(bs->file);
07f07615
PB
4246}
4247
0f15423c
AL
4248void bdrv_invalidate_cache(BlockDriverState *bs)
4249{
4250 if (bs->drv && bs->drv->bdrv_invalidate_cache) {
4251 bs->drv->bdrv_invalidate_cache(bs);
4252 }
4253}
4254
4255void bdrv_invalidate_cache_all(void)
4256{
4257 BlockDriverState *bs;
4258
4259 QTAILQ_FOREACH(bs, &bdrv_states, list) {
4260 bdrv_invalidate_cache(bs);
4261 }
4262}
4263
07789269
BC
4264void bdrv_clear_incoming_migration_all(void)
4265{
4266 BlockDriverState *bs;
4267
4268 QTAILQ_FOREACH(bs, &bdrv_states, list) {
4269 bs->open_flags = bs->open_flags & ~(BDRV_O_INCOMING);
4270 }
4271}
4272
07f07615
PB
4273int bdrv_flush(BlockDriverState *bs)
4274{
4275 Coroutine *co;
4276 RwCo rwco = {
4277 .bs = bs,
4278 .ret = NOT_DONE,
e7a8a783 4279 };
e7a8a783 4280
07f07615
PB
4281 if (qemu_in_coroutine()) {
4282 /* Fast-path if already in coroutine context */
4283 bdrv_flush_co_entry(&rwco);
4284 } else {
4285 co = qemu_coroutine_create(bdrv_flush_co_entry);
4286 qemu_coroutine_enter(co, &rwco);
4287 while (rwco.ret == NOT_DONE) {
4288 qemu_aio_wait();
4289 }
e7a8a783 4290 }
07f07615
PB
4291
4292 return rwco.ret;
e7a8a783
KW
4293}
4294
4265d620
PB
4295static void coroutine_fn bdrv_discard_co_entry(void *opaque)
4296{
4297 RwCo *rwco = opaque;
4298
4299 rwco->ret = bdrv_co_discard(rwco->bs, rwco->sector_num, rwco->nb_sectors);
4300}
4301
6f14da52
PL
4302/* if no limit is specified in the BlockLimits use a default
4303 * of 32768 512-byte sectors (16 MiB) per request.
4304 */
4305#define MAX_DISCARD_DEFAULT 32768
4306
4265d620
PB
4307int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
4308 int nb_sectors)
4309{
d51e9fe5
PB
4310 int max_discard;
4311
4265d620
PB
4312 if (!bs->drv) {
4313 return -ENOMEDIUM;
4314 } else if (bdrv_check_request(bs, sector_num, nb_sectors)) {
4315 return -EIO;
4316 } else if (bs->read_only) {
4317 return -EROFS;
df702c9b
PB
4318 }
4319
e4654d2d 4320 bdrv_reset_dirty(bs, sector_num, nb_sectors);
df702c9b 4321
9e8f1835
PB
4322 /* Do nothing if disabled. */
4323 if (!(bs->open_flags & BDRV_O_UNMAP)) {
4324 return 0;
4325 }
4326
d51e9fe5
PB
4327 if (!bs->drv->bdrv_co_discard && !bs->drv->bdrv_aio_discard) {
4328 return 0;
4329 }
6f14da52 4330
d51e9fe5
PB
4331 max_discard = bs->bl.max_discard ? bs->bl.max_discard : MAX_DISCARD_DEFAULT;
4332 while (nb_sectors > 0) {
4333 int ret;
4334 int num = nb_sectors;
6f14da52 4335
d51e9fe5
PB
4336 /* align request */
4337 if (bs->bl.discard_alignment &&
4338 num >= bs->bl.discard_alignment &&
4339 sector_num % bs->bl.discard_alignment) {
4340 if (num > bs->bl.discard_alignment) {
4341 num = bs->bl.discard_alignment;
6f14da52 4342 }
d51e9fe5
PB
4343 num -= sector_num % bs->bl.discard_alignment;
4344 }
6f14da52 4345
d51e9fe5
PB
4346 /* limit request size */
4347 if (num > max_discard) {
4348 num = max_discard;
4349 }
6f14da52 4350
d51e9fe5 4351 if (bs->drv->bdrv_co_discard) {
6f14da52 4352 ret = bs->drv->bdrv_co_discard(bs, sector_num, num);
d51e9fe5
PB
4353 } else {
4354 BlockDriverAIOCB *acb;
4355 CoroutineIOCompletion co = {
4356 .coroutine = qemu_coroutine_self(),
4357 };
4358
4359 acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors,
4360 bdrv_co_io_em_complete, &co);
4361 if (acb == NULL) {
4362 return -EIO;
4363 } else {
4364 qemu_coroutine_yield();
4365 ret = co.ret;
6f14da52 4366 }
6f14da52 4367 }
d51e9fe5
PB
4368 if (ret) {
4369 return ret;
4265d620 4370 }
d51e9fe5
PB
4371
4372 sector_num += num;
4373 nb_sectors -= num;
4265d620 4374 }
d51e9fe5 4375 return 0;
4265d620
PB
4376}
4377
4378int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors)
4379{
4380 Coroutine *co;
4381 RwCo rwco = {
4382 .bs = bs,
4383 .sector_num = sector_num,
4384 .nb_sectors = nb_sectors,
4385 .ret = NOT_DONE,
4386 };
4387
4388 if (qemu_in_coroutine()) {
4389 /* Fast-path if already in coroutine context */
4390 bdrv_discard_co_entry(&rwco);
4391 } else {
4392 co = qemu_coroutine_create(bdrv_discard_co_entry);
4393 qemu_coroutine_enter(co, &rwco);
4394 while (rwco.ret == NOT_DONE) {
4395 qemu_aio_wait();
4396 }
4397 }
4398
4399 return rwco.ret;
4400}
4401
19cb3738
FB
4402/**************************************************************/
4403/* removable device support */
4404
4405/**
4406 * Return TRUE if the media is present
4407 */
4408int bdrv_is_inserted(BlockDriverState *bs)
4409{
4410 BlockDriver *drv = bs->drv;
a1aff5bf 4411
19cb3738
FB
4412 if (!drv)
4413 return 0;
4414 if (!drv->bdrv_is_inserted)
a1aff5bf
MA
4415 return 1;
4416 return drv->bdrv_is_inserted(bs);
19cb3738
FB
4417}
4418
4419/**
8e49ca46
MA
4420 * Return whether the media changed since the last call to this
4421 * function, or -ENOTSUP if we don't know. Most drivers don't know.
19cb3738
FB
4422 */
4423int bdrv_media_changed(BlockDriverState *bs)
4424{
4425 BlockDriver *drv = bs->drv;
19cb3738 4426
8e49ca46
MA
4427 if (drv && drv->bdrv_media_changed) {
4428 return drv->bdrv_media_changed(bs);
4429 }
4430 return -ENOTSUP;
19cb3738
FB
4431}
4432
4433/**
4434 * If eject_flag is TRUE, eject the media. Otherwise, close the tray
4435 */
f36f3949 4436void bdrv_eject(BlockDriverState *bs, bool eject_flag)
19cb3738
FB
4437{
4438 BlockDriver *drv = bs->drv;
19cb3738 4439
822e1cd1
MA
4440 if (drv && drv->bdrv_eject) {
4441 drv->bdrv_eject(bs, eject_flag);
19cb3738 4442 }
6f382ed2
LC
4443
4444 if (bs->device_name[0] != '\0') {
4445 bdrv_emit_qmp_eject_event(bs, eject_flag);
4446 }
19cb3738
FB
4447}
4448
19cb3738
FB
4449/**
4450 * Lock or unlock the media (if it is locked, the user won't be able
4451 * to eject it manually).
4452 */
025e849a 4453void bdrv_lock_medium(BlockDriverState *bs, bool locked)
19cb3738
FB
4454{
4455 BlockDriver *drv = bs->drv;
4456
025e849a 4457 trace_bdrv_lock_medium(bs, locked);
b8c6d095 4458
025e849a
MA
4459 if (drv && drv->bdrv_lock_medium) {
4460 drv->bdrv_lock_medium(bs, locked);
19cb3738
FB
4461 }
4462}
985a03b0
TS
4463
4464/* needed for generic scsi interface */
4465
4466int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
4467{
4468 BlockDriver *drv = bs->drv;
4469
4470 if (drv && drv->bdrv_ioctl)
4471 return drv->bdrv_ioctl(bs, req, buf);
4472 return -ENOTSUP;
4473}
7d780669 4474
221f715d
AL
4475BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
4476 unsigned long int req, void *buf,
4477 BlockDriverCompletionFunc *cb, void *opaque)
7d780669 4478{
221f715d 4479 BlockDriver *drv = bs->drv;
7d780669 4480
221f715d
AL
4481 if (drv && drv->bdrv_aio_ioctl)
4482 return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque);
4483 return NULL;
7d780669 4484}
e268ca52 4485
7b6f9300
MA
4486void bdrv_set_buffer_alignment(BlockDriverState *bs, int align)
4487{
4488 bs->buffer_alignment = align;
4489}
7cd1e32a 4490
e268ca52
AL
4491void *qemu_blockalign(BlockDriverState *bs, size_t size)
4492{
4493 return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size);
4494}
7cd1e32a 4495
c53b1c51
SH
4496/*
4497 * Check if all memory in this vector is sector aligned.
4498 */
4499bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov)
4500{
4501 int i;
4502
4503 for (i = 0; i < qiov->niov; i++) {
4504 if ((uintptr_t) qiov->iov[i].iov_base % bs->buffer_alignment) {
4505 return false;
4506 }
4507 }
4508
4509 return true;
4510}
4511
e4654d2d 4512BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, int granularity)
7cd1e32a
LS
4513{
4514 int64_t bitmap_size;
e4654d2d 4515 BdrvDirtyBitmap *bitmap;
a55eb92c 4516
50717e94
PB
4517 assert((granularity & (granularity - 1)) == 0);
4518
e4654d2d
FZ
4519 granularity >>= BDRV_SECTOR_BITS;
4520 assert(granularity);
4521 bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS);
4522 bitmap = g_malloc0(sizeof(BdrvDirtyBitmap));
4523 bitmap->bitmap = hbitmap_alloc(bitmap_size, ffs(granularity) - 1);
4524 QLIST_INSERT_HEAD(&bs->dirty_bitmaps, bitmap, list);
4525 return bitmap;
4526}
4527
4528void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
4529{
4530 BdrvDirtyBitmap *bm, *next;
4531 QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) {
4532 if (bm == bitmap) {
4533 QLIST_REMOVE(bitmap, list);
4534 hbitmap_free(bitmap->bitmap);
4535 g_free(bitmap);
4536 return;
a55eb92c 4537 }
7cd1e32a
LS
4538 }
4539}
4540
21b56835
FZ
4541BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
4542{
4543 BdrvDirtyBitmap *bm;
4544 BlockDirtyInfoList *list = NULL;
4545 BlockDirtyInfoList **plist = &list;
4546
4547 QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
4548 BlockDirtyInfo *info = g_malloc0(sizeof(BlockDirtyInfo));
4549 BlockDirtyInfoList *entry = g_malloc0(sizeof(BlockDirtyInfoList));
4550 info->count = bdrv_get_dirty_count(bs, bm);
4551 info->granularity =
4552 ((int64_t) BDRV_SECTOR_SIZE << hbitmap_granularity(bm->bitmap));
4553 entry->value = info;
4554 *plist = entry;
4555 plist = &entry->next;
4556 }
4557
4558 return list;
4559}
4560
e4654d2d 4561int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector)
7cd1e32a 4562{
e4654d2d
FZ
4563 if (bitmap) {
4564 return hbitmap_get(bitmap->bitmap, sector);
7cd1e32a
LS
4565 } else {
4566 return 0;
4567 }
4568}
4569
e4654d2d
FZ
4570void bdrv_dirty_iter_init(BlockDriverState *bs,
4571 BdrvDirtyBitmap *bitmap, HBitmapIter *hbi)
1755da16 4572{
e4654d2d 4573 hbitmap_iter_init(hbi, bitmap->bitmap, 0);
1755da16
PB
4574}
4575
4576void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
4577 int nr_sectors)
4578{
e4654d2d
FZ
4579 BdrvDirtyBitmap *bitmap;
4580 QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
4581 hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
4582 }
1755da16
PB
4583}
4584
e4654d2d 4585void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors)
7cd1e32a 4586{
e4654d2d
FZ
4587 BdrvDirtyBitmap *bitmap;
4588 QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
4589 hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors);
4590 }
7cd1e32a 4591}
aaa0eb75 4592
e4654d2d 4593int64_t bdrv_get_dirty_count(BlockDriverState *bs, BdrvDirtyBitmap *bitmap)
aaa0eb75 4594{
e4654d2d 4595 return hbitmap_count(bitmap->bitmap);
aaa0eb75 4596}
f88e1a42 4597
9fcb0251
FZ
4598/* Get a reference to bs */
4599void bdrv_ref(BlockDriverState *bs)
4600{
4601 bs->refcnt++;
4602}
4603
4604/* Release a previously grabbed reference to bs.
4605 * If after releasing, reference count is zero, the BlockDriverState is
4606 * deleted. */
4607void bdrv_unref(BlockDriverState *bs)
4608{
4609 assert(bs->refcnt > 0);
4610 if (--bs->refcnt == 0) {
4611 bdrv_delete(bs);
4612 }
4613}
4614
db593f25
MT
4615void bdrv_set_in_use(BlockDriverState *bs, int in_use)
4616{
4617 assert(bs->in_use != in_use);
4618 bs->in_use = in_use;
4619}
4620
4621int bdrv_in_use(BlockDriverState *bs)
4622{
4623 return bs->in_use;
4624}
4625
28a7282a
LC
4626void bdrv_iostatus_enable(BlockDriverState *bs)
4627{
d6bf279e 4628 bs->iostatus_enabled = true;
58e21ef5 4629 bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
28a7282a
LC
4630}
4631
4632/* The I/O status is only enabled if the drive explicitly
4633 * enables it _and_ the VM is configured to stop on errors */
4634bool bdrv_iostatus_is_enabled(const BlockDriverState *bs)
4635{
d6bf279e 4636 return (bs->iostatus_enabled &&
92aa5c6d
PB
4637 (bs->on_write_error == BLOCKDEV_ON_ERROR_ENOSPC ||
4638 bs->on_write_error == BLOCKDEV_ON_ERROR_STOP ||
4639 bs->on_read_error == BLOCKDEV_ON_ERROR_STOP));
28a7282a
LC
4640}
4641
4642void bdrv_iostatus_disable(BlockDriverState *bs)
4643{
d6bf279e 4644 bs->iostatus_enabled = false;
28a7282a
LC
4645}
4646
4647void bdrv_iostatus_reset(BlockDriverState *bs)
4648{
4649 if (bdrv_iostatus_is_enabled(bs)) {
58e21ef5 4650 bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
3bd293c3
PB
4651 if (bs->job) {
4652 block_job_iostatus_reset(bs->job);
4653 }
28a7282a
LC
4654 }
4655}
4656
28a7282a
LC
4657void bdrv_iostatus_set_err(BlockDriverState *bs, int error)
4658{
3e1caa5f
PB
4659 assert(bdrv_iostatus_is_enabled(bs));
4660 if (bs->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
58e21ef5
LC
4661 bs->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
4662 BLOCK_DEVICE_IO_STATUS_FAILED;
28a7282a
LC
4663 }
4664}
4665
a597e79c
CH
4666void
4667bdrv_acct_start(BlockDriverState *bs, BlockAcctCookie *cookie, int64_t bytes,
4668 enum BlockAcctType type)
4669{
4670 assert(type < BDRV_MAX_IOTYPE);
4671
4672 cookie->bytes = bytes;
c488c7f6 4673 cookie->start_time_ns = get_clock();
a597e79c
CH
4674 cookie->type = type;
4675}
4676
4677void
4678bdrv_acct_done(BlockDriverState *bs, BlockAcctCookie *cookie)
4679{
4680 assert(cookie->type < BDRV_MAX_IOTYPE);
4681
4682 bs->nr_bytes[cookie->type] += cookie->bytes;
4683 bs->nr_ops[cookie->type]++;
c488c7f6 4684 bs->total_time_ns[cookie->type] += get_clock() - cookie->start_time_ns;
a597e79c
CH
4685}
4686
d92ada22
LC
4687void bdrv_img_create(const char *filename, const char *fmt,
4688 const char *base_filename, const char *base_fmt,
f382d43a
MR
4689 char *options, uint64_t img_size, int flags,
4690 Error **errp, bool quiet)
f88e1a42
JS
4691{
4692 QEMUOptionParameter *param = NULL, *create_options = NULL;
d220894e 4693 QEMUOptionParameter *backing_fmt, *backing_file, *size;
f88e1a42
JS
4694 BlockDriverState *bs = NULL;
4695 BlockDriver *drv, *proto_drv;
96df67d1 4696 BlockDriver *backing_drv = NULL;
cc84d90f 4697 Error *local_err = NULL;
f88e1a42
JS
4698 int ret = 0;
4699
4700 /* Find driver and parse its options */
4701 drv = bdrv_find_format(fmt);
4702 if (!drv) {
71c79813 4703 error_setg(errp, "Unknown file format '%s'", fmt);
d92ada22 4704 return;
f88e1a42
JS
4705 }
4706
98289620 4707 proto_drv = bdrv_find_protocol(filename, true);
f88e1a42 4708 if (!proto_drv) {
71c79813 4709 error_setg(errp, "Unknown protocol '%s'", filename);
d92ada22 4710 return;
f88e1a42
JS
4711 }
4712
4713 create_options = append_option_parameters(create_options,
4714 drv->create_options);
4715 create_options = append_option_parameters(create_options,
4716 proto_drv->create_options);
4717
4718 /* Create parameter list with default values */
4719 param = parse_option_parameters("", create_options, param);
4720
4721 set_option_parameter_int(param, BLOCK_OPT_SIZE, img_size);
4722
4723 /* Parse -o options */
4724 if (options) {
4725 param = parse_option_parameters(options, create_options, param);
4726 if (param == NULL) {
71c79813 4727 error_setg(errp, "Invalid options for file format '%s'.", fmt);
f88e1a42
JS
4728 goto out;
4729 }
4730 }
4731
4732 if (base_filename) {
4733 if (set_option_parameter(param, BLOCK_OPT_BACKING_FILE,
4734 base_filename)) {
71c79813
LC
4735 error_setg(errp, "Backing file not supported for file format '%s'",
4736 fmt);
f88e1a42
JS
4737 goto out;
4738 }
4739 }
4740
4741 if (base_fmt) {
4742 if (set_option_parameter(param, BLOCK_OPT_BACKING_FMT, base_fmt)) {
71c79813
LC
4743 error_setg(errp, "Backing file format not supported for file "
4744 "format '%s'", fmt);
f88e1a42
JS
4745 goto out;
4746 }
4747 }
4748
792da93a
JS
4749 backing_file = get_option_parameter(param, BLOCK_OPT_BACKING_FILE);
4750 if (backing_file && backing_file->value.s) {
4751 if (!strcmp(filename, backing_file->value.s)) {
71c79813
LC
4752 error_setg(errp, "Error: Trying to create an image with the "
4753 "same filename as the backing file");
792da93a
JS
4754 goto out;
4755 }
4756 }
4757
f88e1a42
JS
4758 backing_fmt = get_option_parameter(param, BLOCK_OPT_BACKING_FMT);
4759 if (backing_fmt && backing_fmt->value.s) {
96df67d1
SH
4760 backing_drv = bdrv_find_format(backing_fmt->value.s);
4761 if (!backing_drv) {
71c79813
LC
4762 error_setg(errp, "Unknown backing file format '%s'",
4763 backing_fmt->value.s);
f88e1a42
JS
4764 goto out;
4765 }
4766 }
4767
4768 // The size for the image must always be specified, with one exception:
4769 // If we are using a backing file, we can obtain the size from there
d220894e
KW
4770 size = get_option_parameter(param, BLOCK_OPT_SIZE);
4771 if (size && size->value.n == -1) {
f88e1a42
JS
4772 if (backing_file && backing_file->value.s) {
4773 uint64_t size;
f88e1a42 4774 char buf[32];
63090dac
PB
4775 int back_flags;
4776
4777 /* backing files always opened read-only */
4778 back_flags =
4779 flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
f88e1a42 4780
f88e1a42
JS
4781 bs = bdrv_new("");
4782
de9c0cec 4783 ret = bdrv_open(bs, backing_file->value.s, NULL, back_flags,
cc84d90f 4784 backing_drv, &local_err);
f88e1a42 4785 if (ret < 0) {
cc84d90f
HR
4786 error_setg_errno(errp, -ret, "Could not open '%s': %s",
4787 backing_file->value.s,
4788 error_get_pretty(local_err));
4789 error_free(local_err);
4790 local_err = NULL;
f88e1a42
JS
4791 goto out;
4792 }
4793 bdrv_get_geometry(bs, &size);
4794 size *= 512;
4795
4796 snprintf(buf, sizeof(buf), "%" PRId64, size);
4797 set_option_parameter(param, BLOCK_OPT_SIZE, buf);
4798 } else {
71c79813 4799 error_setg(errp, "Image creation needs a size parameter");
f88e1a42
JS
4800 goto out;
4801 }
4802 }
4803
f382d43a
MR
4804 if (!quiet) {
4805 printf("Formatting '%s', fmt=%s ", filename, fmt);
4806 print_option_parameters(param);
4807 puts("");
4808 }
cc84d90f
HR
4809 ret = bdrv_create(drv, filename, param, &local_err);
4810 if (ret == -EFBIG) {
4811 /* This is generally a better message than whatever the driver would
4812 * deliver (especially because of the cluster_size_hint), since that
4813 * is most probably not much different from "image too large". */
4814 const char *cluster_size_hint = "";
4815 if (get_option_parameter(create_options, BLOCK_OPT_CLUSTER_SIZE)) {
4816 cluster_size_hint = " (try using a larger cluster size)";
f88e1a42 4817 }
cc84d90f
HR
4818 error_setg(errp, "The image size is too large for file format '%s'"
4819 "%s", fmt, cluster_size_hint);
4820 error_free(local_err);
4821 local_err = NULL;
f88e1a42
JS
4822 }
4823
4824out:
4825 free_option_parameters(create_options);
4826 free_option_parameters(param);
4827
4828 if (bs) {
4f6fd349 4829 bdrv_unref(bs);
f88e1a42 4830 }
cc84d90f
HR
4831 if (error_is_set(&local_err)) {
4832 error_propagate(errp, local_err);
4833 }
f88e1a42 4834}
85d126f3
SH
4835
4836AioContext *bdrv_get_aio_context(BlockDriverState *bs)
4837{
4838 /* Currently BlockDriverState always uses the main loop AioContext */
4839 return qemu_get_aio_context();
4840}
d616b224
SH
4841
4842void bdrv_add_before_write_notifier(BlockDriverState *bs,
4843 NotifierWithReturn *notifier)
4844{
4845 notifier_with_return_list_add(&bs->before_write_notifiers, notifier);
4846}
6f176b48
HR
4847
4848int bdrv_amend_options(BlockDriverState *bs, QEMUOptionParameter *options)
4849{
4850 if (bs->drv->bdrv_amend_options == NULL) {
4851 return -ENOTSUP;
4852 }
4853 return bs->drv->bdrv_amend_options(bs, options);
4854}
f6186f49
BC
4855
4856ExtSnapshotPerm bdrv_check_ext_snapshot(BlockDriverState *bs)
4857{
4858 if (bs->drv->bdrv_check_ext_snapshot) {
4859 return bs->drv->bdrv_check_ext_snapshot(bs);
4860 }
4861
4862 if (bs->file && bs->file->drv && bs->file->drv->bdrv_check_ext_snapshot) {
4863 return bs->file->drv->bdrv_check_ext_snapshot(bs);
4864 }
4865
4866 /* external snapshots are allowed by default */
4867 return EXT_SNAPSHOT_ALLOWED;
4868}
4869
4870ExtSnapshotPerm bdrv_check_ext_snapshot_forbidden(BlockDriverState *bs)
4871{
4872 return EXT_SNAPSHOT_FORBIDDEN;
4873}