2 * QEMU Enhanced Disk Format
4 * Copyright IBM, Corp. 2010
7 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
8 * Anthony Liguori <aliguori@us.ibm.com>
10 * This work is licensed under the terms of the GNU LGPL, version 2 or later.
11 * See the COPYING.LIB file in the top-level directory.
15 #include "qemu/osdep.h"
16 #include "qapi/error.h"
17 #include "qemu/timer.h"
18 #include "qemu/bswap.h"
19 #include "qemu/option.h"
22 #include "sysemu/block-backend.h"
24 static int bdrv_qed_probe(const uint8_t *buf
, int buf_size
,
27 const QEDHeader
*header
= (const QEDHeader
*)buf
;
29 if (buf_size
< sizeof(*header
)) {
32 if (le32_to_cpu(header
->magic
) != QED_MAGIC
) {
39 * Check whether an image format is raw
41 * @fmt: Backing file format, may be NULL
43 static bool qed_fmt_is_raw(const char *fmt
)
45 return fmt
&& strcmp(fmt
, "raw") == 0;
48 static void qed_header_le_to_cpu(const QEDHeader
*le
, QEDHeader
*cpu
)
50 cpu
->magic
= le32_to_cpu(le
->magic
);
51 cpu
->cluster_size
= le32_to_cpu(le
->cluster_size
);
52 cpu
->table_size
= le32_to_cpu(le
->table_size
);
53 cpu
->header_size
= le32_to_cpu(le
->header_size
);
54 cpu
->features
= le64_to_cpu(le
->features
);
55 cpu
->compat_features
= le64_to_cpu(le
->compat_features
);
56 cpu
->autoclear_features
= le64_to_cpu(le
->autoclear_features
);
57 cpu
->l1_table_offset
= le64_to_cpu(le
->l1_table_offset
);
58 cpu
->image_size
= le64_to_cpu(le
->image_size
);
59 cpu
->backing_filename_offset
= le32_to_cpu(le
->backing_filename_offset
);
60 cpu
->backing_filename_size
= le32_to_cpu(le
->backing_filename_size
);
63 static void qed_header_cpu_to_le(const QEDHeader
*cpu
, QEDHeader
*le
)
65 le
->magic
= cpu_to_le32(cpu
->magic
);
66 le
->cluster_size
= cpu_to_le32(cpu
->cluster_size
);
67 le
->table_size
= cpu_to_le32(cpu
->table_size
);
68 le
->header_size
= cpu_to_le32(cpu
->header_size
);
69 le
->features
= cpu_to_le64(cpu
->features
);
70 le
->compat_features
= cpu_to_le64(cpu
->compat_features
);
71 le
->autoclear_features
= cpu_to_le64(cpu
->autoclear_features
);
72 le
->l1_table_offset
= cpu_to_le64(cpu
->l1_table_offset
);
73 le
->image_size
= cpu_to_le64(cpu
->image_size
);
74 le
->backing_filename_offset
= cpu_to_le32(cpu
->backing_filename_offset
);
75 le
->backing_filename_size
= cpu_to_le32(cpu
->backing_filename_size
);
78 int qed_write_header_sync(BDRVQEDState
*s
)
83 qed_header_cpu_to_le(&s
->header
, &le
);
84 ret
= bdrv_pwrite(s
->bs
->file
, 0, &le
, sizeof(le
));
85 if (ret
!= sizeof(le
)) {
92 * Update header in-place (does not rewrite backing filename or other strings)
94 * This function only updates known header fields in-place and does not affect
95 * extra data after the QED header.
97 * No new allocating reqs can start while this function runs.
99 static int coroutine_fn
qed_write_header(BDRVQEDState
*s
)
101 /* We must write full sectors for O_DIRECT but cannot necessarily generate
102 * the data following the header if an unrecognized compat feature is
103 * active. Therefore, first read the sectors containing the header, update
104 * them, and write back.
107 int nsectors
= DIV_ROUND_UP(sizeof(QEDHeader
), BDRV_SECTOR_SIZE
);
108 size_t len
= nsectors
* BDRV_SECTOR_SIZE
;
114 assert(s
->allocating_acb
|| s
->allocating_write_reqs_plugged
);
116 buf
= qemu_blockalign(s
->bs
, len
);
117 iov
= (struct iovec
) {
121 qemu_iovec_init_external(&qiov
, &iov
, 1);
123 ret
= bdrv_co_preadv(s
->bs
->file
, 0, qiov
.size
, &qiov
, 0);
129 qed_header_cpu_to_le(&s
->header
, (QEDHeader
*) buf
);
131 ret
= bdrv_co_pwritev(s
->bs
->file
, 0, qiov
.size
, &qiov
, 0);
142 static uint64_t qed_max_image_size(uint32_t cluster_size
, uint32_t table_size
)
144 uint64_t table_entries
;
147 table_entries
= (table_size
* cluster_size
) / sizeof(uint64_t);
148 l2_size
= table_entries
* cluster_size
;
150 return l2_size
* table_entries
;
153 static bool qed_is_cluster_size_valid(uint32_t cluster_size
)
155 if (cluster_size
< QED_MIN_CLUSTER_SIZE
||
156 cluster_size
> QED_MAX_CLUSTER_SIZE
) {
159 if (cluster_size
& (cluster_size
- 1)) {
160 return false; /* not power of 2 */
165 static bool qed_is_table_size_valid(uint32_t table_size
)
167 if (table_size
< QED_MIN_TABLE_SIZE
||
168 table_size
> QED_MAX_TABLE_SIZE
) {
171 if (table_size
& (table_size
- 1)) {
172 return false; /* not power of 2 */
177 static bool qed_is_image_size_valid(uint64_t image_size
, uint32_t cluster_size
,
180 if (image_size
% BDRV_SECTOR_SIZE
!= 0) {
181 return false; /* not multiple of sector size */
183 if (image_size
> qed_max_image_size(cluster_size
, table_size
)) {
184 return false; /* image is too large */
190 * Read a string of known length from the image file
193 * @offset: File offset to start of string, in bytes
194 * @n: String length in bytes
195 * @buf: Destination buffer
196 * @buflen: Destination buffer length in bytes
197 * @ret: 0 on success, -errno on failure
199 * The string is NUL-terminated.
201 static int qed_read_string(BdrvChild
*file
, uint64_t offset
, size_t n
,
202 char *buf
, size_t buflen
)
208 ret
= bdrv_pread(file
, offset
, buf
, n
);
217 * Allocate new clusters
220 * @n: Number of contiguous clusters to allocate
221 * @ret: Offset of first allocated cluster
223 * This function only produces the offset where the new clusters should be
224 * written. It updates BDRVQEDState but does not make any changes to the image
227 * Called with table_lock held.
229 static uint64_t qed_alloc_clusters(BDRVQEDState
*s
, unsigned int n
)
231 uint64_t offset
= s
->file_size
;
232 s
->file_size
+= n
* s
->header
.cluster_size
;
236 QEDTable
*qed_alloc_table(BDRVQEDState
*s
)
238 /* Honor O_DIRECT memory alignment requirements */
239 return qemu_blockalign(s
->bs
,
240 s
->header
.cluster_size
* s
->header
.table_size
);
244 * Allocate a new zeroed L2 table
246 * Called with table_lock held.
248 static CachedL2Table
*qed_new_l2_table(BDRVQEDState
*s
)
250 CachedL2Table
*l2_table
= qed_alloc_l2_cache_entry(&s
->l2_cache
);
252 l2_table
->table
= qed_alloc_table(s
);
253 l2_table
->offset
= qed_alloc_clusters(s
, s
->header
.table_size
);
255 memset(l2_table
->table
->offsets
, 0,
256 s
->header
.cluster_size
* s
->header
.table_size
);
260 static bool qed_plug_allocating_write_reqs(BDRVQEDState
*s
)
262 qemu_co_mutex_lock(&s
->table_lock
);
264 /* No reentrancy is allowed. */
265 assert(!s
->allocating_write_reqs_plugged
);
266 if (s
->allocating_acb
!= NULL
) {
267 /* Another allocating write came concurrently. This cannot happen
268 * from bdrv_qed_co_drain_begin, but it can happen when the timer runs.
270 qemu_co_mutex_unlock(&s
->table_lock
);
274 s
->allocating_write_reqs_plugged
= true;
275 qemu_co_mutex_unlock(&s
->table_lock
);
279 static void qed_unplug_allocating_write_reqs(BDRVQEDState
*s
)
281 qemu_co_mutex_lock(&s
->table_lock
);
282 assert(s
->allocating_write_reqs_plugged
);
283 s
->allocating_write_reqs_plugged
= false;
284 qemu_co_queue_next(&s
->allocating_write_reqs
);
285 qemu_co_mutex_unlock(&s
->table_lock
);
288 static void coroutine_fn
qed_need_check_timer_entry(void *opaque
)
290 BDRVQEDState
*s
= opaque
;
293 trace_qed_need_check_timer_cb(s
);
295 if (!qed_plug_allocating_write_reqs(s
)) {
299 /* Ensure writes are on disk before clearing flag */
300 ret
= bdrv_co_flush(s
->bs
->file
->bs
);
302 qed_unplug_allocating_write_reqs(s
);
306 s
->header
.features
&= ~QED_F_NEED_CHECK
;
307 ret
= qed_write_header(s
);
310 qed_unplug_allocating_write_reqs(s
);
312 ret
= bdrv_co_flush(s
->bs
);
316 static void qed_need_check_timer_cb(void *opaque
)
318 Coroutine
*co
= qemu_coroutine_create(qed_need_check_timer_entry
, opaque
);
319 qemu_coroutine_enter(co
);
322 static void qed_start_need_check_timer(BDRVQEDState
*s
)
324 trace_qed_start_need_check_timer(s
);
326 /* Use QEMU_CLOCK_VIRTUAL so we don't alter the image file while suspended for
329 timer_mod(s
->need_check_timer
, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL
) +
330 NANOSECONDS_PER_SECOND
* QED_NEED_CHECK_TIMEOUT
);
333 /* It's okay to call this multiple times or when no timer is started */
334 static void qed_cancel_need_check_timer(BDRVQEDState
*s
)
336 trace_qed_cancel_need_check_timer(s
);
337 timer_del(s
->need_check_timer
);
340 static void bdrv_qed_detach_aio_context(BlockDriverState
*bs
)
342 BDRVQEDState
*s
= bs
->opaque
;
344 qed_cancel_need_check_timer(s
);
345 timer_free(s
->need_check_timer
);
348 static void bdrv_qed_attach_aio_context(BlockDriverState
*bs
,
349 AioContext
*new_context
)
351 BDRVQEDState
*s
= bs
->opaque
;
353 s
->need_check_timer
= aio_timer_new(new_context
,
354 QEMU_CLOCK_VIRTUAL
, SCALE_NS
,
355 qed_need_check_timer_cb
, s
);
356 if (s
->header
.features
& QED_F_NEED_CHECK
) {
357 qed_start_need_check_timer(s
);
361 static void coroutine_fn
bdrv_qed_co_drain_begin(BlockDriverState
*bs
)
363 BDRVQEDState
*s
= bs
->opaque
;
365 /* Fire the timer immediately in order to start doing I/O as soon as the
368 if (s
->need_check_timer
&& timer_pending(s
->need_check_timer
)) {
369 qed_cancel_need_check_timer(s
);
370 qed_need_check_timer_entry(s
);
374 static void bdrv_qed_init_state(BlockDriverState
*bs
)
376 BDRVQEDState
*s
= bs
->opaque
;
378 memset(s
, 0, sizeof(BDRVQEDState
));
380 qemu_co_mutex_init(&s
->table_lock
);
381 qemu_co_queue_init(&s
->allocating_write_reqs
);
384 static int bdrv_qed_do_open(BlockDriverState
*bs
, QDict
*options
, int flags
,
387 BDRVQEDState
*s
= bs
->opaque
;
392 ret
= bdrv_pread(bs
->file
, 0, &le_header
, sizeof(le_header
));
396 qed_header_le_to_cpu(&le_header
, &s
->header
);
398 if (s
->header
.magic
!= QED_MAGIC
) {
399 error_setg(errp
, "Image not in QED format");
402 if (s
->header
.features
& ~QED_FEATURE_MASK
) {
403 /* image uses unsupported feature bits */
404 error_setg(errp
, "Unsupported QED features: %" PRIx64
,
405 s
->header
.features
& ~QED_FEATURE_MASK
);
408 if (!qed_is_cluster_size_valid(s
->header
.cluster_size
)) {
412 /* Round down file size to the last cluster */
413 file_size
= bdrv_getlength(bs
->file
->bs
);
417 s
->file_size
= qed_start_of_cluster(s
, file_size
);
419 if (!qed_is_table_size_valid(s
->header
.table_size
)) {
422 if (!qed_is_image_size_valid(s
->header
.image_size
,
423 s
->header
.cluster_size
,
424 s
->header
.table_size
)) {
427 if (!qed_check_table_offset(s
, s
->header
.l1_table_offset
)) {
431 s
->table_nelems
= (s
->header
.cluster_size
* s
->header
.table_size
) /
433 s
->l2_shift
= ctz32(s
->header
.cluster_size
);
434 s
->l2_mask
= s
->table_nelems
- 1;
435 s
->l1_shift
= s
->l2_shift
+ ctz32(s
->table_nelems
);
437 /* Header size calculation must not overflow uint32_t */
438 if (s
->header
.header_size
> UINT32_MAX
/ s
->header
.cluster_size
) {
442 if ((s
->header
.features
& QED_F_BACKING_FILE
)) {
443 if ((uint64_t)s
->header
.backing_filename_offset
+
444 s
->header
.backing_filename_size
>
445 s
->header
.cluster_size
* s
->header
.header_size
) {
449 ret
= qed_read_string(bs
->file
, s
->header
.backing_filename_offset
,
450 s
->header
.backing_filename_size
, bs
->backing_file
,
451 sizeof(bs
->backing_file
));
456 if (s
->header
.features
& QED_F_BACKING_FORMAT_NO_PROBE
) {
457 pstrcpy(bs
->backing_format
, sizeof(bs
->backing_format
), "raw");
461 /* Reset unknown autoclear feature bits. This is a backwards
462 * compatibility mechanism that allows images to be opened by older
463 * programs, which "knock out" unknown feature bits. When an image is
464 * opened by a newer program again it can detect that the autoclear
465 * feature is no longer valid.
467 if ((s
->header
.autoclear_features
& ~QED_AUTOCLEAR_FEATURE_MASK
) != 0 &&
468 !bdrv_is_read_only(bs
->file
->bs
) && !(flags
& BDRV_O_INACTIVE
)) {
469 s
->header
.autoclear_features
&= QED_AUTOCLEAR_FEATURE_MASK
;
471 ret
= qed_write_header_sync(s
);
476 /* From here on only known autoclear feature bits are valid */
477 bdrv_flush(bs
->file
->bs
);
480 s
->l1_table
= qed_alloc_table(s
);
481 qed_init_l2_cache(&s
->l2_cache
);
483 ret
= qed_read_l1_table_sync(s
);
488 /* If image was not closed cleanly, check consistency */
489 if (!(flags
& BDRV_O_CHECK
) && (s
->header
.features
& QED_F_NEED_CHECK
)) {
490 /* Read-only images cannot be fixed. There is no risk of corruption
491 * since write operations are not possible. Therefore, allow
492 * potentially inconsistent images to be opened read-only. This can
493 * aid data recovery from an otherwise inconsistent image.
495 if (!bdrv_is_read_only(bs
->file
->bs
) &&
496 !(flags
& BDRV_O_INACTIVE
)) {
497 BdrvCheckResult result
= {0};
499 ret
= qed_check(s
, &result
, true);
506 bdrv_qed_attach_aio_context(bs
, bdrv_get_aio_context(bs
));
510 qed_free_l2_cache(&s
->l2_cache
);
511 qemu_vfree(s
->l1_table
);
516 static int bdrv_qed_open(BlockDriverState
*bs
, QDict
*options
, int flags
,
519 bs
->file
= bdrv_open_child(NULL
, options
, "file", bs
, &child_file
,
525 bdrv_qed_init_state(bs
);
526 return bdrv_qed_do_open(bs
, options
, flags
, errp
);
529 static void bdrv_qed_refresh_limits(BlockDriverState
*bs
, Error
**errp
)
531 BDRVQEDState
*s
= bs
->opaque
;
533 bs
->bl
.pwrite_zeroes_alignment
= s
->header
.cluster_size
;
536 /* We have nothing to do for QED reopen, stubs just return
538 static int bdrv_qed_reopen_prepare(BDRVReopenState
*state
,
539 BlockReopenQueue
*queue
, Error
**errp
)
544 static void bdrv_qed_close(BlockDriverState
*bs
)
546 BDRVQEDState
*s
= bs
->opaque
;
548 bdrv_qed_detach_aio_context(bs
);
550 /* Ensure writes reach stable storage */
551 bdrv_flush(bs
->file
->bs
);
553 /* Clean shutdown, no check required on next open */
554 if (s
->header
.features
& QED_F_NEED_CHECK
) {
555 s
->header
.features
&= ~QED_F_NEED_CHECK
;
556 qed_write_header_sync(s
);
559 qed_free_l2_cache(&s
->l2_cache
);
560 qemu_vfree(s
->l1_table
);
563 static int qed_create(const char *filename
, uint32_t cluster_size
,
564 uint64_t image_size
, uint32_t table_size
,
565 const char *backing_file
, const char *backing_fmt
,
566 QemuOpts
*opts
, Error
**errp
)
570 .cluster_size
= cluster_size
,
571 .table_size
= table_size
,
574 .compat_features
= 0,
575 .l1_table_offset
= cluster_size
,
576 .image_size
= image_size
,
579 uint8_t *l1_table
= NULL
;
580 size_t l1_size
= header
.cluster_size
* header
.table_size
;
581 Error
*local_err
= NULL
;
585 ret
= bdrv_create_file(filename
, opts
, &local_err
);
587 error_propagate(errp
, local_err
);
591 blk
= blk_new_open(filename
, NULL
, NULL
,
592 BDRV_O_RDWR
| BDRV_O_RESIZE
| BDRV_O_PROTOCOL
,
595 error_propagate(errp
, local_err
);
599 blk_set_allow_write_beyond_eof(blk
, true);
601 /* File must start empty and grow, check truncate is supported */
602 ret
= blk_truncate(blk
, 0, PREALLOC_MODE_OFF
, errp
);
608 header
.features
|= QED_F_BACKING_FILE
;
609 header
.backing_filename_offset
= sizeof(le_header
);
610 header
.backing_filename_size
= strlen(backing_file
);
612 if (qed_fmt_is_raw(backing_fmt
)) {
613 header
.features
|= QED_F_BACKING_FORMAT_NO_PROBE
;
617 qed_header_cpu_to_le(&header
, &le_header
);
618 ret
= blk_pwrite(blk
, 0, &le_header
, sizeof(le_header
), 0);
622 ret
= blk_pwrite(blk
, sizeof(le_header
), backing_file
,
623 header
.backing_filename_size
, 0);
628 l1_table
= g_malloc0(l1_size
);
629 ret
= blk_pwrite(blk
, header
.l1_table_offset
, l1_table
, l1_size
, 0);
634 ret
= 0; /* success */
641 static int coroutine_fn
bdrv_qed_co_create_opts(const char *filename
,
645 uint64_t image_size
= 0;
646 uint32_t cluster_size
= QED_DEFAULT_CLUSTER_SIZE
;
647 uint32_t table_size
= QED_DEFAULT_TABLE_SIZE
;
648 char *backing_file
= NULL
;
649 char *backing_fmt
= NULL
;
652 image_size
= ROUND_UP(qemu_opt_get_size_del(opts
, BLOCK_OPT_SIZE
, 0),
654 backing_file
= qemu_opt_get_del(opts
, BLOCK_OPT_BACKING_FILE
);
655 backing_fmt
= qemu_opt_get_del(opts
, BLOCK_OPT_BACKING_FMT
);
656 cluster_size
= qemu_opt_get_size_del(opts
,
657 BLOCK_OPT_CLUSTER_SIZE
,
658 QED_DEFAULT_CLUSTER_SIZE
);
659 table_size
= qemu_opt_get_size_del(opts
, BLOCK_OPT_TABLE_SIZE
,
660 QED_DEFAULT_TABLE_SIZE
);
662 if (!qed_is_cluster_size_valid(cluster_size
)) {
663 error_setg(errp
, "QED cluster size must be within range [%u, %u] "
665 QED_MIN_CLUSTER_SIZE
, QED_MAX_CLUSTER_SIZE
);
669 if (!qed_is_table_size_valid(table_size
)) {
670 error_setg(errp
, "QED table size must be within range [%u, %u] "
672 QED_MIN_TABLE_SIZE
, QED_MAX_TABLE_SIZE
);
676 if (!qed_is_image_size_valid(image_size
, cluster_size
, table_size
)) {
677 error_setg(errp
, "QED image size must be a non-zero multiple of "
678 "cluster size and less than %" PRIu64
" bytes",
679 qed_max_image_size(cluster_size
, table_size
));
684 ret
= qed_create(filename
, cluster_size
, image_size
, table_size
,
685 backing_file
, backing_fmt
, opts
, errp
);
688 g_free(backing_file
);
693 static int coroutine_fn
bdrv_qed_co_block_status(BlockDriverState
*bs
,
695 int64_t pos
, int64_t bytes
,
696 int64_t *pnum
, int64_t *map
,
697 BlockDriverState
**file
)
699 BDRVQEDState
*s
= bs
->opaque
;
700 size_t len
= MIN(bytes
, SIZE_MAX
);
702 QEDRequest request
= { .l2_table
= NULL
};
706 qemu_co_mutex_lock(&s
->table_lock
);
707 ret
= qed_find_cluster(s
, &request
, pos
, &len
, &offset
);
711 case QED_CLUSTER_FOUND
:
712 *map
= offset
| qed_offset_into_cluster(s
, pos
);
713 status
= BDRV_BLOCK_DATA
| BDRV_BLOCK_OFFSET_VALID
;
714 *file
= bs
->file
->bs
;
716 case QED_CLUSTER_ZERO
:
717 status
= BDRV_BLOCK_ZERO
;
729 qed_unref_l2_cache_entry(request
.l2_table
);
730 qemu_co_mutex_unlock(&s
->table_lock
);
735 static BDRVQEDState
*acb_to_s(QEDAIOCB
*acb
)
737 return acb
->bs
->opaque
;
741 * Read from the backing file or zero-fill if no backing file
744 * @pos: Byte position in device
745 * @qiov: Destination I/O vector
746 * @backing_qiov: Possibly shortened copy of qiov, to be allocated here
747 * @cb: Completion function
748 * @opaque: User data for completion function
750 * This function reads qiov->size bytes starting at pos from the backing file.
751 * If there is no backing file then zeroes are read.
753 static int coroutine_fn
qed_read_backing_file(BDRVQEDState
*s
, uint64_t pos
,
755 QEMUIOVector
**backing_qiov
)
757 uint64_t backing_length
= 0;
761 /* If there is a backing file, get its length. Treat the absence of a
762 * backing file like a zero length backing file.
764 if (s
->bs
->backing
) {
765 int64_t l
= bdrv_getlength(s
->bs
->backing
->bs
);
772 /* Zero all sectors if reading beyond the end of the backing file */
773 if (pos
>= backing_length
||
774 pos
+ qiov
->size
> backing_length
) {
775 qemu_iovec_memset(qiov
, 0, 0, qiov
->size
);
778 /* Complete now if there are no backing file sectors to read */
779 if (pos
>= backing_length
) {
783 /* If the read straddles the end of the backing file, shorten it */
784 size
= MIN((uint64_t)backing_length
- pos
, qiov
->size
);
786 assert(*backing_qiov
== NULL
);
787 *backing_qiov
= g_new(QEMUIOVector
, 1);
788 qemu_iovec_init(*backing_qiov
, qiov
->niov
);
789 qemu_iovec_concat(*backing_qiov
, qiov
, 0, size
);
791 BLKDBG_EVENT(s
->bs
->file
, BLKDBG_READ_BACKING_AIO
);
792 ret
= bdrv_co_preadv(s
->bs
->backing
, pos
, size
, *backing_qiov
, 0);
800 * Copy data from backing file into the image
803 * @pos: Byte position in device
804 * @len: Number of bytes
805 * @offset: Byte offset in image file
807 static int coroutine_fn
qed_copy_from_backing_file(BDRVQEDState
*s
,
808 uint64_t pos
, uint64_t len
,
812 QEMUIOVector
*backing_qiov
= NULL
;
816 /* Skip copy entirely if there is no work to do */
821 iov
= (struct iovec
) {
822 .iov_base
= qemu_blockalign(s
->bs
, len
),
825 qemu_iovec_init_external(&qiov
, &iov
, 1);
827 ret
= qed_read_backing_file(s
, pos
, &qiov
, &backing_qiov
);
830 qemu_iovec_destroy(backing_qiov
);
831 g_free(backing_qiov
);
839 BLKDBG_EVENT(s
->bs
->file
, BLKDBG_COW_WRITE
);
840 ret
= bdrv_co_pwritev(s
->bs
->file
, offset
, qiov
.size
, &qiov
, 0);
846 qemu_vfree(iov
.iov_base
);
851 * Link one or more contiguous clusters into a table
855 * @index: First cluster index
856 * @n: Number of contiguous clusters
857 * @cluster: First cluster offset
859 * The cluster offset may be an allocated byte offset in the image file, the
860 * zero cluster marker, or the unallocated cluster marker.
862 * Called with table_lock held.
864 static void coroutine_fn
qed_update_l2_table(BDRVQEDState
*s
, QEDTable
*table
,
865 int index
, unsigned int n
,
869 for (i
= index
; i
< index
+ n
; i
++) {
870 table
->offsets
[i
] = cluster
;
871 if (!qed_offset_is_unalloc_cluster(cluster
) &&
872 !qed_offset_is_zero_cluster(cluster
)) {
873 cluster
+= s
->header
.cluster_size
;
878 /* Called with table_lock held. */
879 static void coroutine_fn
qed_aio_complete(QEDAIOCB
*acb
)
881 BDRVQEDState
*s
= acb_to_s(acb
);
884 qemu_iovec_destroy(&acb
->cur_qiov
);
885 qed_unref_l2_cache_entry(acb
->request
.l2_table
);
887 /* Free the buffer we may have allocated for zero writes */
888 if (acb
->flags
& QED_AIOCB_ZERO
) {
889 qemu_vfree(acb
->qiov
->iov
[0].iov_base
);
890 acb
->qiov
->iov
[0].iov_base
= NULL
;
893 /* Start next allocating write request waiting behind this one. Note that
894 * requests enqueue themselves when they first hit an unallocated cluster
895 * but they wait until the entire request is finished before waking up the
896 * next request in the queue. This ensures that we don't cycle through
897 * requests multiple times but rather finish one at a time completely.
899 if (acb
== s
->allocating_acb
) {
900 s
->allocating_acb
= NULL
;
901 if (!qemu_co_queue_empty(&s
->allocating_write_reqs
)) {
902 qemu_co_queue_next(&s
->allocating_write_reqs
);
903 } else if (s
->header
.features
& QED_F_NEED_CHECK
) {
904 qed_start_need_check_timer(s
);
910 * Update L1 table with new L2 table offset and write it out
912 * Called with table_lock held.
914 static int coroutine_fn
qed_aio_write_l1_update(QEDAIOCB
*acb
)
916 BDRVQEDState
*s
= acb_to_s(acb
);
917 CachedL2Table
*l2_table
= acb
->request
.l2_table
;
918 uint64_t l2_offset
= l2_table
->offset
;
921 index
= qed_l1_index(s
, acb
->cur_pos
);
922 s
->l1_table
->offsets
[index
] = l2_table
->offset
;
924 ret
= qed_write_l1_table(s
, index
, 1);
926 /* Commit the current L2 table to the cache */
927 qed_commit_l2_cache_entry(&s
->l2_cache
, l2_table
);
929 /* This is guaranteed to succeed because we just committed the entry to the
932 acb
->request
.l2_table
= qed_find_l2_cache_entry(&s
->l2_cache
, l2_offset
);
933 assert(acb
->request
.l2_table
!= NULL
);
940 * Update L2 table with new cluster offsets and write them out
942 * Called with table_lock held.
944 static int coroutine_fn
qed_aio_write_l2_update(QEDAIOCB
*acb
, uint64_t offset
)
946 BDRVQEDState
*s
= acb_to_s(acb
);
947 bool need_alloc
= acb
->find_cluster_ret
== QED_CLUSTER_L1
;
951 qed_unref_l2_cache_entry(acb
->request
.l2_table
);
952 acb
->request
.l2_table
= qed_new_l2_table(s
);
955 index
= qed_l2_index(s
, acb
->cur_pos
);
956 qed_update_l2_table(s
, acb
->request
.l2_table
->table
, index
, acb
->cur_nclusters
,
960 /* Write out the whole new L2 table */
961 ret
= qed_write_l2_table(s
, &acb
->request
, 0, s
->table_nelems
, true);
965 return qed_aio_write_l1_update(acb
);
967 /* Write out only the updated part of the L2 table */
968 ret
= qed_write_l2_table(s
, &acb
->request
, index
, acb
->cur_nclusters
,
978 * Write data to the image file
980 * Called with table_lock *not* held.
982 static int coroutine_fn
qed_aio_write_main(QEDAIOCB
*acb
)
984 BDRVQEDState
*s
= acb_to_s(acb
);
985 uint64_t offset
= acb
->cur_cluster
+
986 qed_offset_into_cluster(s
, acb
->cur_pos
);
988 trace_qed_aio_write_main(s
, acb
, 0, offset
, acb
->cur_qiov
.size
);
990 BLKDBG_EVENT(s
->bs
->file
, BLKDBG_WRITE_AIO
);
991 return bdrv_co_pwritev(s
->bs
->file
, offset
, acb
->cur_qiov
.size
,
996 * Populate untouched regions of new data cluster
998 * Called with table_lock held.
1000 static int coroutine_fn
qed_aio_write_cow(QEDAIOCB
*acb
)
1002 BDRVQEDState
*s
= acb_to_s(acb
);
1003 uint64_t start
, len
, offset
;
1006 qemu_co_mutex_unlock(&s
->table_lock
);
1008 /* Populate front untouched region of new data cluster */
1009 start
= qed_start_of_cluster(s
, acb
->cur_pos
);
1010 len
= qed_offset_into_cluster(s
, acb
->cur_pos
);
1012 trace_qed_aio_write_prefill(s
, acb
, start
, len
, acb
->cur_cluster
);
1013 ret
= qed_copy_from_backing_file(s
, start
, len
, acb
->cur_cluster
);
1018 /* Populate back untouched region of new data cluster */
1019 start
= acb
->cur_pos
+ acb
->cur_qiov
.size
;
1020 len
= qed_start_of_cluster(s
, start
+ s
->header
.cluster_size
- 1) - start
;
1021 offset
= acb
->cur_cluster
+
1022 qed_offset_into_cluster(s
, acb
->cur_pos
) +
1025 trace_qed_aio_write_postfill(s
, acb
, start
, len
, offset
);
1026 ret
= qed_copy_from_backing_file(s
, start
, len
, offset
);
1031 ret
= qed_aio_write_main(acb
);
1036 if (s
->bs
->backing
) {
1038 * Flush new data clusters before updating the L2 table
1040 * This flush is necessary when a backing file is in use. A crash
1041 * during an allocating write could result in empty clusters in the
1042 * image. If the write only touched a subregion of the cluster,
1043 * then backing image sectors have been lost in the untouched
1044 * region. The solution is to flush after writing a new data
1045 * cluster and before updating the L2 table.
1047 ret
= bdrv_co_flush(s
->bs
->file
->bs
);
1051 qemu_co_mutex_lock(&s
->table_lock
);
1056 * Check if the QED_F_NEED_CHECK bit should be set during allocating write
1058 static bool qed_should_set_need_check(BDRVQEDState
*s
)
1060 /* The flush before L2 update path ensures consistency */
1061 if (s
->bs
->backing
) {
1065 return !(s
->header
.features
& QED_F_NEED_CHECK
);
1069 * Write new data cluster
1071 * @acb: Write request
1072 * @len: Length in bytes
1074 * This path is taken when writing to previously unallocated clusters.
1076 * Called with table_lock held.
1078 static int coroutine_fn
qed_aio_write_alloc(QEDAIOCB
*acb
, size_t len
)
1080 BDRVQEDState
*s
= acb_to_s(acb
);
1083 /* Cancel timer when the first allocating request comes in */
1084 if (s
->allocating_acb
== NULL
) {
1085 qed_cancel_need_check_timer(s
);
1088 /* Freeze this request if another allocating write is in progress */
1089 if (s
->allocating_acb
!= acb
|| s
->allocating_write_reqs_plugged
) {
1090 if (s
->allocating_acb
!= NULL
) {
1091 qemu_co_queue_wait(&s
->allocating_write_reqs
, &s
->table_lock
);
1092 assert(s
->allocating_acb
== NULL
);
1094 s
->allocating_acb
= acb
;
1095 return -EAGAIN
; /* start over with looking up table entries */
1098 acb
->cur_nclusters
= qed_bytes_to_clusters(s
,
1099 qed_offset_into_cluster(s
, acb
->cur_pos
) + len
);
1100 qemu_iovec_concat(&acb
->cur_qiov
, acb
->qiov
, acb
->qiov_offset
, len
);
1102 if (acb
->flags
& QED_AIOCB_ZERO
) {
1103 /* Skip ahead if the clusters are already zero */
1104 if (acb
->find_cluster_ret
== QED_CLUSTER_ZERO
) {
1107 acb
->cur_cluster
= 1;
1109 acb
->cur_cluster
= qed_alloc_clusters(s
, acb
->cur_nclusters
);
1112 if (qed_should_set_need_check(s
)) {
1113 s
->header
.features
|= QED_F_NEED_CHECK
;
1114 ret
= qed_write_header(s
);
1120 if (!(acb
->flags
& QED_AIOCB_ZERO
)) {
1121 ret
= qed_aio_write_cow(acb
);
1127 return qed_aio_write_l2_update(acb
, acb
->cur_cluster
);
1131 * Write data cluster in place
1133 * @acb: Write request
1134 * @offset: Cluster offset in bytes
1135 * @len: Length in bytes
1137 * This path is taken when writing to already allocated clusters.
1139 * Called with table_lock held.
1141 static int coroutine_fn
qed_aio_write_inplace(QEDAIOCB
*acb
, uint64_t offset
,
1144 BDRVQEDState
*s
= acb_to_s(acb
);
1147 qemu_co_mutex_unlock(&s
->table_lock
);
1149 /* Allocate buffer for zero writes */
1150 if (acb
->flags
& QED_AIOCB_ZERO
) {
1151 struct iovec
*iov
= acb
->qiov
->iov
;
1153 if (!iov
->iov_base
) {
1154 iov
->iov_base
= qemu_try_blockalign(acb
->bs
, iov
->iov_len
);
1155 if (iov
->iov_base
== NULL
) {
1159 memset(iov
->iov_base
, 0, iov
->iov_len
);
1163 /* Calculate the I/O vector */
1164 acb
->cur_cluster
= offset
;
1165 qemu_iovec_concat(&acb
->cur_qiov
, acb
->qiov
, acb
->qiov_offset
, len
);
1167 /* Do the actual write. */
1168 r
= qed_aio_write_main(acb
);
1170 qemu_co_mutex_lock(&s
->table_lock
);
1175 * Write data cluster
1177 * @opaque: Write request
1178 * @ret: QED_CLUSTER_FOUND, QED_CLUSTER_L2 or QED_CLUSTER_L1
1179 * @offset: Cluster offset in bytes
1180 * @len: Length in bytes
1182 * Called with table_lock held.
1184 static int coroutine_fn
qed_aio_write_data(void *opaque
, int ret
,
1185 uint64_t offset
, size_t len
)
1187 QEDAIOCB
*acb
= opaque
;
1189 trace_qed_aio_write_data(acb_to_s(acb
), acb
, ret
, offset
, len
);
1191 acb
->find_cluster_ret
= ret
;
1194 case QED_CLUSTER_FOUND
:
1195 return qed_aio_write_inplace(acb
, offset
, len
);
1197 case QED_CLUSTER_L2
:
1198 case QED_CLUSTER_L1
:
1199 case QED_CLUSTER_ZERO
:
1200 return qed_aio_write_alloc(acb
, len
);
1203 g_assert_not_reached();
1210 * @opaque: Read request
1211 * @ret: QED_CLUSTER_FOUND, QED_CLUSTER_L2 or QED_CLUSTER_L1
1212 * @offset: Cluster offset in bytes
1213 * @len: Length in bytes
1215 * Called with table_lock held.
1217 static int coroutine_fn
qed_aio_read_data(void *opaque
, int ret
,
1218 uint64_t offset
, size_t len
)
1220 QEDAIOCB
*acb
= opaque
;
1221 BDRVQEDState
*s
= acb_to_s(acb
);
1222 BlockDriverState
*bs
= acb
->bs
;
1225 qemu_co_mutex_unlock(&s
->table_lock
);
1227 /* Adjust offset into cluster */
1228 offset
+= qed_offset_into_cluster(s
, acb
->cur_pos
);
1230 trace_qed_aio_read_data(s
, acb
, ret
, offset
, len
);
1232 qemu_iovec_concat(&acb
->cur_qiov
, acb
->qiov
, acb
->qiov_offset
, len
);
1234 /* Handle zero cluster and backing file reads, otherwise read
1235 * data cluster directly.
1237 if (ret
== QED_CLUSTER_ZERO
) {
1238 qemu_iovec_memset(&acb
->cur_qiov
, 0, 0, acb
->cur_qiov
.size
);
1240 } else if (ret
!= QED_CLUSTER_FOUND
) {
1241 r
= qed_read_backing_file(s
, acb
->cur_pos
, &acb
->cur_qiov
,
1242 &acb
->backing_qiov
);
1244 BLKDBG_EVENT(bs
->file
, BLKDBG_READ_AIO
);
1245 r
= bdrv_co_preadv(bs
->file
, offset
, acb
->cur_qiov
.size
,
1249 qemu_co_mutex_lock(&s
->table_lock
);
1254 * Begin next I/O or complete the request
1256 static int coroutine_fn
qed_aio_next_io(QEDAIOCB
*acb
)
1258 BDRVQEDState
*s
= acb_to_s(acb
);
1263 qemu_co_mutex_lock(&s
->table_lock
);
1265 trace_qed_aio_next_io(s
, acb
, 0, acb
->cur_pos
+ acb
->cur_qiov
.size
);
1267 if (acb
->backing_qiov
) {
1268 qemu_iovec_destroy(acb
->backing_qiov
);
1269 g_free(acb
->backing_qiov
);
1270 acb
->backing_qiov
= NULL
;
1273 acb
->qiov_offset
+= acb
->cur_qiov
.size
;
1274 acb
->cur_pos
+= acb
->cur_qiov
.size
;
1275 qemu_iovec_reset(&acb
->cur_qiov
);
1277 /* Complete request */
1278 if (acb
->cur_pos
>= acb
->end_pos
) {
1283 /* Find next cluster and start I/O */
1284 len
= acb
->end_pos
- acb
->cur_pos
;
1285 ret
= qed_find_cluster(s
, &acb
->request
, acb
->cur_pos
, &len
, &offset
);
1290 if (acb
->flags
& QED_AIOCB_WRITE
) {
1291 ret
= qed_aio_write_data(acb
, ret
, offset
, len
);
1293 ret
= qed_aio_read_data(acb
, ret
, offset
, len
);
1296 if (ret
< 0 && ret
!= -EAGAIN
) {
1301 trace_qed_aio_complete(s
, acb
, ret
);
1302 qed_aio_complete(acb
);
1303 qemu_co_mutex_unlock(&s
->table_lock
);
1307 static int coroutine_fn
qed_co_request(BlockDriverState
*bs
, int64_t sector_num
,
1308 QEMUIOVector
*qiov
, int nb_sectors
,
1313 .cur_pos
= (uint64_t) sector_num
* BDRV_SECTOR_SIZE
,
1314 .end_pos
= (sector_num
+ nb_sectors
) * BDRV_SECTOR_SIZE
,
1318 qemu_iovec_init(&acb
.cur_qiov
, qiov
->niov
);
1320 trace_qed_aio_setup(bs
->opaque
, &acb
, sector_num
, nb_sectors
, NULL
, flags
);
1323 return qed_aio_next_io(&acb
);
1326 static int coroutine_fn
bdrv_qed_co_readv(BlockDriverState
*bs
,
1327 int64_t sector_num
, int nb_sectors
,
1330 return qed_co_request(bs
, sector_num
, qiov
, nb_sectors
, 0);
1333 static int coroutine_fn
bdrv_qed_co_writev(BlockDriverState
*bs
,
1334 int64_t sector_num
, int nb_sectors
,
1337 return qed_co_request(bs
, sector_num
, qiov
, nb_sectors
, QED_AIOCB_WRITE
);
1340 static int coroutine_fn
bdrv_qed_co_pwrite_zeroes(BlockDriverState
*bs
,
1343 BdrvRequestFlags flags
)
1345 BDRVQEDState
*s
= bs
->opaque
;
1349 /* Fall back if the request is not aligned */
1350 if (qed_offset_into_cluster(s
, offset
) ||
1351 qed_offset_into_cluster(s
, bytes
)) {
1355 /* Zero writes start without an I/O buffer. If a buffer becomes necessary
1356 * then it will be allocated during request processing.
1358 iov
.iov_base
= NULL
;
1359 iov
.iov_len
= bytes
;
1361 qemu_iovec_init_external(&qiov
, &iov
, 1);
1362 return qed_co_request(bs
, offset
>> BDRV_SECTOR_BITS
, &qiov
,
1363 bytes
>> BDRV_SECTOR_BITS
,
1364 QED_AIOCB_WRITE
| QED_AIOCB_ZERO
);
1367 static int bdrv_qed_truncate(BlockDriverState
*bs
, int64_t offset
,
1368 PreallocMode prealloc
, Error
**errp
)
1370 BDRVQEDState
*s
= bs
->opaque
;
1371 uint64_t old_image_size
;
1374 if (prealloc
!= PREALLOC_MODE_OFF
) {
1375 error_setg(errp
, "Unsupported preallocation mode '%s'",
1376 PreallocMode_str(prealloc
));
1380 if (!qed_is_image_size_valid(offset
, s
->header
.cluster_size
,
1381 s
->header
.table_size
)) {
1382 error_setg(errp
, "Invalid image size specified");
1386 if ((uint64_t)offset
< s
->header
.image_size
) {
1387 error_setg(errp
, "Shrinking images is currently not supported");
1391 old_image_size
= s
->header
.image_size
;
1392 s
->header
.image_size
= offset
;
1393 ret
= qed_write_header_sync(s
);
1395 s
->header
.image_size
= old_image_size
;
1396 error_setg_errno(errp
, -ret
, "Failed to update the image size");
1401 static int64_t bdrv_qed_getlength(BlockDriverState
*bs
)
1403 BDRVQEDState
*s
= bs
->opaque
;
1404 return s
->header
.image_size
;
1407 static int bdrv_qed_get_info(BlockDriverState
*bs
, BlockDriverInfo
*bdi
)
1409 BDRVQEDState
*s
= bs
->opaque
;
1411 memset(bdi
, 0, sizeof(*bdi
));
1412 bdi
->cluster_size
= s
->header
.cluster_size
;
1413 bdi
->is_dirty
= s
->header
.features
& QED_F_NEED_CHECK
;
1414 bdi
->unallocated_blocks_are_zero
= true;
1418 static int bdrv_qed_change_backing_file(BlockDriverState
*bs
,
1419 const char *backing_file
,
1420 const char *backing_fmt
)
1422 BDRVQEDState
*s
= bs
->opaque
;
1423 QEDHeader new_header
, le_header
;
1425 size_t buffer_len
, backing_file_len
;
1428 /* Refuse to set backing filename if unknown compat feature bits are
1429 * active. If the image uses an unknown compat feature then we may not
1430 * know the layout of data following the header structure and cannot safely
1433 if (backing_file
&& (s
->header
.compat_features
&
1434 ~QED_COMPAT_FEATURE_MASK
)) {
1438 memcpy(&new_header
, &s
->header
, sizeof(new_header
));
1440 new_header
.features
&= ~(QED_F_BACKING_FILE
|
1441 QED_F_BACKING_FORMAT_NO_PROBE
);
1443 /* Adjust feature flags */
1445 new_header
.features
|= QED_F_BACKING_FILE
;
1447 if (qed_fmt_is_raw(backing_fmt
)) {
1448 new_header
.features
|= QED_F_BACKING_FORMAT_NO_PROBE
;
1452 /* Calculate new header size */
1453 backing_file_len
= 0;
1456 backing_file_len
= strlen(backing_file
);
1459 buffer_len
= sizeof(new_header
);
1460 new_header
.backing_filename_offset
= buffer_len
;
1461 new_header
.backing_filename_size
= backing_file_len
;
1462 buffer_len
+= backing_file_len
;
1464 /* Make sure we can rewrite header without failing */
1465 if (buffer_len
> new_header
.header_size
* new_header
.cluster_size
) {
1469 /* Prepare new header */
1470 buffer
= g_malloc(buffer_len
);
1472 qed_header_cpu_to_le(&new_header
, &le_header
);
1473 memcpy(buffer
, &le_header
, sizeof(le_header
));
1474 buffer_len
= sizeof(le_header
);
1477 memcpy(buffer
+ buffer_len
, backing_file
, backing_file_len
);
1478 buffer_len
+= backing_file_len
;
1481 /* Write new header */
1482 ret
= bdrv_pwrite_sync(bs
->file
, 0, buffer
, buffer_len
);
1485 memcpy(&s
->header
, &new_header
, sizeof(new_header
));
1490 static void bdrv_qed_invalidate_cache(BlockDriverState
*bs
, Error
**errp
)
1492 BDRVQEDState
*s
= bs
->opaque
;
1493 Error
*local_err
= NULL
;
1498 bdrv_qed_init_state(bs
);
1499 if (qemu_in_coroutine()) {
1500 qemu_co_mutex_lock(&s
->table_lock
);
1502 ret
= bdrv_qed_do_open(bs
, NULL
, bs
->open_flags
, &local_err
);
1503 if (qemu_in_coroutine()) {
1504 qemu_co_mutex_unlock(&s
->table_lock
);
1507 error_propagate(errp
, local_err
);
1508 error_prepend(errp
, "Could not reopen qed layer: ");
1510 } else if (ret
< 0) {
1511 error_setg_errno(errp
, -ret
, "Could not reopen qed layer");
1516 static int bdrv_qed_check(BlockDriverState
*bs
, BdrvCheckResult
*result
,
1519 BDRVQEDState
*s
= bs
->opaque
;
1521 return qed_check(s
, result
, !!fix
);
1524 static QemuOptsList qed_create_opts
= {
1525 .name
= "qed-create-opts",
1526 .head
= QTAILQ_HEAD_INITIALIZER(qed_create_opts
.head
),
1529 .name
= BLOCK_OPT_SIZE
,
1530 .type
= QEMU_OPT_SIZE
,
1531 .help
= "Virtual disk size"
1534 .name
= BLOCK_OPT_BACKING_FILE
,
1535 .type
= QEMU_OPT_STRING
,
1536 .help
= "File name of a base image"
1539 .name
= BLOCK_OPT_BACKING_FMT
,
1540 .type
= QEMU_OPT_STRING
,
1541 .help
= "Image format of the base image"
1544 .name
= BLOCK_OPT_CLUSTER_SIZE
,
1545 .type
= QEMU_OPT_SIZE
,
1546 .help
= "Cluster size (in bytes)",
1547 .def_value_str
= stringify(QED_DEFAULT_CLUSTER_SIZE
)
1550 .name
= BLOCK_OPT_TABLE_SIZE
,
1551 .type
= QEMU_OPT_SIZE
,
1552 .help
= "L1/L2 table size (in clusters)"
1554 { /* end of list */ }
1558 static BlockDriver bdrv_qed
= {
1559 .format_name
= "qed",
1560 .instance_size
= sizeof(BDRVQEDState
),
1561 .create_opts
= &qed_create_opts
,
1562 .supports_backing
= true,
1564 .bdrv_probe
= bdrv_qed_probe
,
1565 .bdrv_open
= bdrv_qed_open
,
1566 .bdrv_close
= bdrv_qed_close
,
1567 .bdrv_reopen_prepare
= bdrv_qed_reopen_prepare
,
1568 .bdrv_child_perm
= bdrv_format_default_perms
,
1569 .bdrv_co_create_opts
= bdrv_qed_co_create_opts
,
1570 .bdrv_has_zero_init
= bdrv_has_zero_init_1
,
1571 .bdrv_co_block_status
= bdrv_qed_co_block_status
,
1572 .bdrv_co_readv
= bdrv_qed_co_readv
,
1573 .bdrv_co_writev
= bdrv_qed_co_writev
,
1574 .bdrv_co_pwrite_zeroes
= bdrv_qed_co_pwrite_zeroes
,
1575 .bdrv_truncate
= bdrv_qed_truncate
,
1576 .bdrv_getlength
= bdrv_qed_getlength
,
1577 .bdrv_get_info
= bdrv_qed_get_info
,
1578 .bdrv_refresh_limits
= bdrv_qed_refresh_limits
,
1579 .bdrv_change_backing_file
= bdrv_qed_change_backing_file
,
1580 .bdrv_invalidate_cache
= bdrv_qed_invalidate_cache
,
1581 .bdrv_check
= bdrv_qed_check
,
1582 .bdrv_detach_aio_context
= bdrv_qed_detach_aio_context
,
1583 .bdrv_attach_aio_context
= bdrv_qed_attach_aio_context
,
1584 .bdrv_co_drain_begin
= bdrv_qed_co_drain_begin
,
1587 static void bdrv_qed_init(void)
1589 bdrv_register(&bdrv_qed
);
1592 block_init(bdrv_qed_init
);