6 #include "qemu/option.h"
7 #include "qemu/coroutine.h"
8 #include "block/accounting.h"
9 #include "block/dirty-bitmap.h"
10 #include "block/blockjob.h"
11 #include "qapi/qmp/qobject.h"
12 #include "qapi-types.h"
13 #include "qemu/hbitmap.h"
16 typedef struct BlockDriver BlockDriver
;
17 typedef struct BdrvChild BdrvChild
;
18 typedef struct BdrvChildRole BdrvChildRole
;
20 typedef struct BlockDriverInfo
{
21 /* in bytes, 0 if irrelevant */
23 /* offset at which the VM state can be saved (0 if not possible) */
24 int64_t vm_state_offset
;
27 * True if unallocated blocks read back as zeroes. This is equivalent
28 * to the LBPRZ flag in the SCSI logical block provisioning page.
30 bool unallocated_blocks_are_zero
;
32 * True if the driver can optimize writing zeroes by unmapping
33 * sectors. This is equivalent to the BLKDISCARDZEROES ioctl in Linux
34 * with the difference that in qemu a discard is allowed to silently
35 * fail. Therefore we have to use bdrv_pwrite_zeroes with the
36 * BDRV_REQ_MAY_UNMAP flag for an optimized zero write with unmapping.
37 * After this call the driver has to guarantee that the contents read
38 * back as zero. It is additionally required that the block device is
39 * opened with BDRV_O_UNMAP flag for this to work.
41 bool can_write_zeroes_with_unmap
;
43 * True if this block driver only supports compressed writes
45 bool needs_compressed_writes
;
48 typedef struct BlockFragInfo
{
49 uint64_t allocated_clusters
;
50 uint64_t total_clusters
;
51 uint64_t fragmented_clusters
;
52 uint64_t compressed_clusters
;
56 BDRV_REQ_COPY_ON_READ
= 0x1,
57 BDRV_REQ_ZERO_WRITE
= 0x2,
58 /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver
59 * is allowed to optimize a write zeroes request by unmapping (discarding)
60 * blocks if it is guaranteed that the result will read back as
61 * zeroes. The flag is only passed to the driver if the block device is
62 * opened with BDRV_O_UNMAP.
64 BDRV_REQ_MAY_UNMAP
= 0x4,
65 BDRV_REQ_NO_SERIALISING
= 0x8,
67 BDRV_REQ_WRITE_COMPRESSED
= 0x20,
69 /* Mask of valid flags */
73 typedef struct BlockSizes
{
78 typedef struct HDGeometry
{
84 #define BDRV_O_RDWR 0x0002
85 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */
86 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */
87 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */
88 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */
89 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */
90 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */
91 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */
92 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
93 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */
94 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */
95 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */
96 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */
97 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given:
98 select an appropriate protocol driver,
99 ignoring the format layer */
100 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */
102 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH)
105 /* Option names of options parsed by the block layer */
107 #define BDRV_OPT_CACHE_WB "cache.writeback"
108 #define BDRV_OPT_CACHE_DIRECT "cache.direct"
109 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush"
110 #define BDRV_OPT_READ_ONLY "read-only"
111 #define BDRV_OPT_DISCARD "discard"
114 #define BDRV_SECTOR_BITS 9
115 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS)
116 #define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1)
118 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \
119 INT_MAX >> BDRV_SECTOR_BITS)
120 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS)
123 * Allocation status flags
124 * BDRV_BLOCK_DATA: data is read from a file returned by bdrv_get_block_status.
125 * BDRV_BLOCK_ZERO: sectors read as zero
126 * BDRV_BLOCK_OFFSET_VALID: sector stored as raw data in a file returned by
127 * bdrv_get_block_status.
128 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
129 * layer (as opposed to the backing file)
130 * BDRV_BLOCK_RAW: used internally to indicate that the request
131 * was answered by the raw driver and that one
132 * should look in bs->file directly.
134 * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 represent the offset in
135 * bs->file where sector data can be read from as raw data.
137 * DATA == 0 && ZERO == 0 means that data is read from backing_hd if present.
139 * DATA ZERO OFFSET_VALID
140 * t t t sectors read as zero, bs->file is zero at offset
141 * t f t sectors read as valid from bs->file at offset
142 * f t t sectors preallocated, read as zero, bs->file not
143 * necessarily zero at offset
144 * f f t sectors preallocated but read from backing_hd,
145 * bs->file contains garbage at offset
146 * t t f sectors preallocated, read as zero, unknown offset
147 * t f f sectors read from unknown file or offset
148 * f t f not allocated or unknown offset, read as zero
149 * f f f not allocated or unknown offset, read from backing_hd
151 #define BDRV_BLOCK_DATA 0x01
152 #define BDRV_BLOCK_ZERO 0x02
153 #define BDRV_BLOCK_OFFSET_VALID 0x04
154 #define BDRV_BLOCK_RAW 0x08
155 #define BDRV_BLOCK_ALLOCATED 0x10
156 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK
158 typedef QSIMPLEQ_HEAD(BlockReopenQueue
, BlockReopenQueueEntry
) BlockReopenQueue
;
160 typedef struct BDRVReopenState
{
161 BlockDriverState
*bs
;
164 QDict
*explicit_options
;
169 * Block operation types
171 typedef enum BlockOpType
{
172 BLOCK_OP_TYPE_BACKUP_SOURCE
,
173 BLOCK_OP_TYPE_BACKUP_TARGET
,
174 BLOCK_OP_TYPE_CHANGE
,
175 BLOCK_OP_TYPE_COMMIT_SOURCE
,
176 BLOCK_OP_TYPE_COMMIT_TARGET
,
177 BLOCK_OP_TYPE_DATAPLANE
,
178 BLOCK_OP_TYPE_DRIVE_DEL
,
180 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT
,
181 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT
,
182 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE
,
183 BLOCK_OP_TYPE_MIRROR_SOURCE
,
184 BLOCK_OP_TYPE_MIRROR_TARGET
,
185 BLOCK_OP_TYPE_RESIZE
,
186 BLOCK_OP_TYPE_STREAM
,
187 BLOCK_OP_TYPE_REPLACE
,
191 /* Block node permission constants */
194 * A user that has the "permission" of consistent reads is guaranteed that
195 * their view of the contents of the block device is complete and
196 * self-consistent, representing the contents of a disk at a specific
199 * For most block devices (including their backing files) this is true, but
200 * the property cannot be maintained in a few situations like for
201 * intermediate nodes of a commit block job.
203 BLK_PERM_CONSISTENT_READ
= 0x01,
205 /** This permission is required to change the visible disk contents. */
206 BLK_PERM_WRITE
= 0x02,
209 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and
210 * required for writes to the block node when the caller promises that
211 * the visible disk content doesn't change.
213 BLK_PERM_WRITE_UNCHANGED
= 0x04,
215 /** This permission is required to change the size of a block node. */
216 BLK_PERM_RESIZE
= 0x08,
219 * This permission is required to change the node that this BdrvChild
222 BLK_PERM_GRAPH_MOD
= 0x10,
227 /* disk I/O throttling */
228 void bdrv_init(void);
229 void bdrv_init_with_whitelist(void);
230 bool bdrv_uses_whitelist(void);
231 BlockDriver
*bdrv_find_protocol(const char *filename
,
232 bool allow_protocol_prefix
,
234 BlockDriver
*bdrv_find_format(const char *format_name
);
235 int bdrv_create(BlockDriver
*drv
, const char* filename
,
236 QemuOpts
*opts
, Error
**errp
);
237 int bdrv_create_file(const char *filename
, QemuOpts
*opts
, Error
**errp
);
238 BlockDriverState
*bdrv_new(void);
239 void bdrv_append(BlockDriverState
*bs_new
, BlockDriverState
*bs_top
);
240 void bdrv_replace_in_backing_chain(BlockDriverState
*old
,
241 BlockDriverState
*new);
243 int bdrv_parse_cache_mode(const char *mode
, int *flags
, bool *writethrough
);
244 int bdrv_parse_discard_flags(const char *mode
, int *flags
);
245 BdrvChild
*bdrv_open_child(const char *filename
,
246 QDict
*options
, const char *bdref_key
,
247 BlockDriverState
* parent
,
248 const BdrvChildRole
*child_role
,
249 bool allow_none
, Error
**errp
);
250 void bdrv_set_backing_hd(BlockDriverState
*bs
, BlockDriverState
*backing_hd
,
252 int bdrv_open_backing_file(BlockDriverState
*bs
, QDict
*parent_options
,
253 const char *bdref_key
, Error
**errp
);
254 BlockDriverState
*bdrv_open(const char *filename
, const char *reference
,
255 QDict
*options
, int flags
, Error
**errp
);
256 BlockDriverState
*bdrv_new_open_driver(BlockDriver
*drv
, const char *node_name
,
257 int flags
, Error
**errp
);
258 BlockReopenQueue
*bdrv_reopen_queue(BlockReopenQueue
*bs_queue
,
259 BlockDriverState
*bs
,
260 QDict
*options
, int flags
);
261 int bdrv_reopen_multiple(AioContext
*ctx
, BlockReopenQueue
*bs_queue
, Error
**errp
);
262 int bdrv_reopen(BlockDriverState
*bs
, int bdrv_flags
, Error
**errp
);
263 int bdrv_reopen_prepare(BDRVReopenState
*reopen_state
,
264 BlockReopenQueue
*queue
, Error
**errp
);
265 void bdrv_reopen_commit(BDRVReopenState
*reopen_state
);
266 void bdrv_reopen_abort(BDRVReopenState
*reopen_state
);
267 int bdrv_read(BdrvChild
*child
, int64_t sector_num
,
268 uint8_t *buf
, int nb_sectors
);
269 int bdrv_write(BdrvChild
*child
, int64_t sector_num
,
270 const uint8_t *buf
, int nb_sectors
);
271 int bdrv_pwrite_zeroes(BdrvChild
*child
, int64_t offset
,
272 int count
, BdrvRequestFlags flags
);
273 int bdrv_make_zero(BdrvChild
*child
, BdrvRequestFlags flags
);
274 int bdrv_pread(BdrvChild
*child
, int64_t offset
, void *buf
, int bytes
);
275 int bdrv_preadv(BdrvChild
*child
, int64_t offset
, QEMUIOVector
*qiov
);
276 int bdrv_pwrite(BdrvChild
*child
, int64_t offset
, const void *buf
, int bytes
);
277 int bdrv_pwritev(BdrvChild
*child
, int64_t offset
, QEMUIOVector
*qiov
);
278 int bdrv_pwrite_sync(BdrvChild
*child
, int64_t offset
,
279 const void *buf
, int count
);
280 int coroutine_fn
bdrv_co_readv(BdrvChild
*child
, int64_t sector_num
,
281 int nb_sectors
, QEMUIOVector
*qiov
);
282 int coroutine_fn
bdrv_co_writev(BdrvChild
*child
, int64_t sector_num
,
283 int nb_sectors
, QEMUIOVector
*qiov
);
285 * Efficiently zero a region of the disk image. Note that this is a regular
286 * I/O request like read or write and should have a reasonable size. This
287 * function is not suitable for zeroing the entire image in a single request
288 * because it may allocate memory for the entire region.
290 int coroutine_fn
bdrv_co_pwrite_zeroes(BdrvChild
*child
, int64_t offset
,
291 int count
, BdrvRequestFlags flags
);
292 BlockDriverState
*bdrv_find_backing_image(BlockDriverState
*bs
,
293 const char *backing_file
);
294 int bdrv_get_backing_file_depth(BlockDriverState
*bs
);
295 void bdrv_refresh_filename(BlockDriverState
*bs
);
296 int bdrv_truncate(BdrvChild
*child
, int64_t offset
);
297 int64_t bdrv_nb_sectors(BlockDriverState
*bs
);
298 int64_t bdrv_getlength(BlockDriverState
*bs
);
299 int64_t bdrv_get_allocated_file_size(BlockDriverState
*bs
);
300 void bdrv_get_geometry(BlockDriverState
*bs
, uint64_t *nb_sectors_ptr
);
301 void bdrv_refresh_limits(BlockDriverState
*bs
, Error
**errp
);
302 int bdrv_commit(BlockDriverState
*bs
);
303 int bdrv_change_backing_file(BlockDriverState
*bs
,
304 const char *backing_file
, const char *backing_fmt
);
305 void bdrv_register(BlockDriver
*bdrv
);
306 int bdrv_drop_intermediate(BlockDriverState
*active
, BlockDriverState
*top
,
307 BlockDriverState
*base
,
308 const char *backing_file_str
);
309 BlockDriverState
*bdrv_find_overlay(BlockDriverState
*active
,
310 BlockDriverState
*bs
);
311 BlockDriverState
*bdrv_find_base(BlockDriverState
*bs
);
314 typedef struct BdrvCheckResult
{
318 int corruptions_fixed
;
320 int64_t image_end_offset
;
329 int bdrv_check(BlockDriverState
*bs
, BdrvCheckResult
*res
, BdrvCheckMode fix
);
331 /* The units of offset and total_work_size may be chosen arbitrarily by the
332 * block driver; total_work_size may change during the course of the amendment
334 typedef void BlockDriverAmendStatusCB(BlockDriverState
*bs
, int64_t offset
,
335 int64_t total_work_size
, void *opaque
);
336 int bdrv_amend_options(BlockDriverState
*bs_new
, QemuOpts
*opts
,
337 BlockDriverAmendStatusCB
*status_cb
, void *cb_opaque
);
339 /* external snapshots */
340 bool bdrv_recurse_is_first_non_filter(BlockDriverState
*bs
,
341 BlockDriverState
*candidate
);
342 bool bdrv_is_first_non_filter(BlockDriverState
*candidate
);
344 /* check if a named node can be replaced when doing drive-mirror */
345 BlockDriverState
*check_to_replace_node(BlockDriverState
*parent_bs
,
346 const char *node_name
, Error
**errp
);
348 /* async block I/O */
349 BlockAIOCB
*bdrv_aio_readv(BdrvChild
*child
, int64_t sector_num
,
350 QEMUIOVector
*iov
, int nb_sectors
,
351 BlockCompletionFunc
*cb
, void *opaque
);
352 BlockAIOCB
*bdrv_aio_writev(BdrvChild
*child
, int64_t sector_num
,
353 QEMUIOVector
*iov
, int nb_sectors
,
354 BlockCompletionFunc
*cb
, void *opaque
);
355 BlockAIOCB
*bdrv_aio_flush(BlockDriverState
*bs
,
356 BlockCompletionFunc
*cb
, void *opaque
);
357 void bdrv_aio_cancel(BlockAIOCB
*acb
);
358 void bdrv_aio_cancel_async(BlockAIOCB
*acb
);
360 /* sg packet commands */
361 int bdrv_co_ioctl(BlockDriverState
*bs
, int req
, void *buf
);
363 /* Invalidate any cached metadata used by image formats */
364 void bdrv_invalidate_cache(BlockDriverState
*bs
, Error
**errp
);
365 void bdrv_invalidate_cache_all(Error
**errp
);
366 int bdrv_inactivate_all(void);
368 /* Ensure contents are flushed to disk. */
369 int bdrv_flush(BlockDriverState
*bs
);
370 int coroutine_fn
bdrv_co_flush(BlockDriverState
*bs
);
371 int bdrv_flush_all(void);
372 void bdrv_close_all(void);
373 void bdrv_drain(BlockDriverState
*bs
);
374 void coroutine_fn
bdrv_co_drain(BlockDriverState
*bs
);
375 void bdrv_drain_all_begin(void);
376 void bdrv_drain_all_end(void);
377 void bdrv_drain_all(void);
379 #define BDRV_POLL_WHILE(bs, cond) ({ \
380 bool waited_ = false; \
381 BlockDriverState *bs_ = (bs); \
382 AioContext *ctx_ = bdrv_get_aio_context(bs_); \
383 if (aio_context_in_iothread(ctx_)) { \
385 aio_poll(ctx_, true); \
389 assert(qemu_get_current_aio_context() == \
390 qemu_get_aio_context()); \
391 /* Ask bdrv_dec_in_flight to wake up the main \
392 * QEMU AioContext. Extra I/O threads never take \
393 * other I/O threads' AioContexts (see for example \
394 * block_job_defer_to_main_loop for how to do it). \
396 assert(!bs_->wakeup); \
397 bs_->wakeup = true; \
399 aio_context_release(ctx_); \
400 aio_poll(qemu_get_aio_context(), true); \
401 aio_context_acquire(ctx_); \
404 bs_->wakeup = false; \
408 int bdrv_pdiscard(BlockDriverState
*bs
, int64_t offset
, int count
);
409 int bdrv_co_pdiscard(BlockDriverState
*bs
, int64_t offset
, int count
);
410 int bdrv_has_zero_init_1(BlockDriverState
*bs
);
411 int bdrv_has_zero_init(BlockDriverState
*bs
);
412 bool bdrv_unallocated_blocks_are_zero(BlockDriverState
*bs
);
413 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState
*bs
);
414 int64_t bdrv_get_block_status(BlockDriverState
*bs
, int64_t sector_num
,
415 int nb_sectors
, int *pnum
,
416 BlockDriverState
**file
);
417 int64_t bdrv_get_block_status_above(BlockDriverState
*bs
,
418 BlockDriverState
*base
,
420 int nb_sectors
, int *pnum
,
421 BlockDriverState
**file
);
422 int bdrv_is_allocated(BlockDriverState
*bs
, int64_t sector_num
, int nb_sectors
,
424 int bdrv_is_allocated_above(BlockDriverState
*top
, BlockDriverState
*base
,
425 int64_t sector_num
, int nb_sectors
, int *pnum
);
427 bool bdrv_is_read_only(BlockDriverState
*bs
);
428 bool bdrv_is_sg(BlockDriverState
*bs
);
429 bool bdrv_is_inserted(BlockDriverState
*bs
);
430 int bdrv_media_changed(BlockDriverState
*bs
);
431 void bdrv_lock_medium(BlockDriverState
*bs
, bool locked
);
432 void bdrv_eject(BlockDriverState
*bs
, bool eject_flag
);
433 const char *bdrv_get_format_name(BlockDriverState
*bs
);
434 BlockDriverState
*bdrv_find_node(const char *node_name
);
435 BlockDeviceInfoList
*bdrv_named_nodes_list(Error
**errp
);
436 BlockDriverState
*bdrv_lookup_bs(const char *device
,
437 const char *node_name
,
439 bool bdrv_chain_contains(BlockDriverState
*top
, BlockDriverState
*base
);
440 BlockDriverState
*bdrv_next_node(BlockDriverState
*bs
);
442 typedef struct BdrvNextIterator
{
444 BDRV_NEXT_BACKEND_ROOTS
,
445 BDRV_NEXT_MONITOR_OWNED
,
448 BlockDriverState
*bs
;
451 BlockDriverState
*bdrv_first(BdrvNextIterator
*it
);
452 BlockDriverState
*bdrv_next(BdrvNextIterator
*it
);
454 BlockDriverState
*bdrv_next_monitor_owned(BlockDriverState
*bs
);
455 bool bdrv_is_encrypted(BlockDriverState
*bs
);
456 bool bdrv_key_required(BlockDriverState
*bs
);
457 int bdrv_set_key(BlockDriverState
*bs
, const char *key
);
458 void bdrv_add_key(BlockDriverState
*bs
, const char *key
, Error
**errp
);
459 void bdrv_iterate_format(void (*it
)(void *opaque
, const char *name
),
461 const char *bdrv_get_node_name(const BlockDriverState
*bs
);
462 const char *bdrv_get_device_name(const BlockDriverState
*bs
);
463 const char *bdrv_get_device_or_node_name(const BlockDriverState
*bs
);
464 int bdrv_get_flags(BlockDriverState
*bs
);
465 int bdrv_get_info(BlockDriverState
*bs
, BlockDriverInfo
*bdi
);
466 ImageInfoSpecific
*bdrv_get_specific_info(BlockDriverState
*bs
);
467 void bdrv_round_sectors_to_clusters(BlockDriverState
*bs
,
468 int64_t sector_num
, int nb_sectors
,
469 int64_t *cluster_sector_num
,
470 int *cluster_nb_sectors
);
471 void bdrv_round_to_clusters(BlockDriverState
*bs
,
472 int64_t offset
, unsigned int bytes
,
473 int64_t *cluster_offset
,
474 unsigned int *cluster_bytes
);
476 const char *bdrv_get_encrypted_filename(BlockDriverState
*bs
);
477 void bdrv_get_backing_filename(BlockDriverState
*bs
,
478 char *filename
, int filename_size
);
479 void bdrv_get_full_backing_filename(BlockDriverState
*bs
,
480 char *dest
, size_t sz
, Error
**errp
);
481 void bdrv_get_full_backing_filename_from_filename(const char *backed
,
483 char *dest
, size_t sz
,
486 int path_has_protocol(const char *path
);
487 int path_is_absolute(const char *path
);
488 void path_combine(char *dest
, int dest_size
,
489 const char *base_path
,
490 const char *filename
);
492 int bdrv_readv_vmstate(BlockDriverState
*bs
, QEMUIOVector
*qiov
, int64_t pos
);
493 int bdrv_writev_vmstate(BlockDriverState
*bs
, QEMUIOVector
*qiov
, int64_t pos
);
494 int bdrv_save_vmstate(BlockDriverState
*bs
, const uint8_t *buf
,
495 int64_t pos
, int size
);
497 int bdrv_load_vmstate(BlockDriverState
*bs
, uint8_t *buf
,
498 int64_t pos
, int size
);
500 void bdrv_img_create(const char *filename
, const char *fmt
,
501 const char *base_filename
, const char *base_fmt
,
502 char *options
, uint64_t img_size
, int flags
,
503 Error
**errp
, bool quiet
);
505 /* Returns the alignment in bytes that is required so that no bounce buffer
506 * is required throughout the stack */
507 size_t bdrv_min_mem_align(BlockDriverState
*bs
);
508 /* Returns optimal alignment in bytes for bounce buffer */
509 size_t bdrv_opt_mem_align(BlockDriverState
*bs
);
510 void *qemu_blockalign(BlockDriverState
*bs
, size_t size
);
511 void *qemu_blockalign0(BlockDriverState
*bs
, size_t size
);
512 void *qemu_try_blockalign(BlockDriverState
*bs
, size_t size
);
513 void *qemu_try_blockalign0(BlockDriverState
*bs
, size_t size
);
514 bool bdrv_qiov_is_aligned(BlockDriverState
*bs
, QEMUIOVector
*qiov
);
516 void bdrv_enable_copy_on_read(BlockDriverState
*bs
);
517 void bdrv_disable_copy_on_read(BlockDriverState
*bs
);
519 void bdrv_ref(BlockDriverState
*bs
);
520 void bdrv_unref(BlockDriverState
*bs
);
521 void bdrv_unref_child(BlockDriverState
*parent
, BdrvChild
*child
);
522 BdrvChild
*bdrv_attach_child(BlockDriverState
*parent_bs
,
523 BlockDriverState
*child_bs
,
524 const char *child_name
,
525 const BdrvChildRole
*child_role
,
528 bool bdrv_op_is_blocked(BlockDriverState
*bs
, BlockOpType op
, Error
**errp
);
529 void bdrv_op_block(BlockDriverState
*bs
, BlockOpType op
, Error
*reason
);
530 void bdrv_op_unblock(BlockDriverState
*bs
, BlockOpType op
, Error
*reason
);
531 void bdrv_op_block_all(BlockDriverState
*bs
, Error
*reason
);
532 void bdrv_op_unblock_all(BlockDriverState
*bs
, Error
*reason
);
533 bool bdrv_op_blocker_is_empty(BlockDriverState
*bs
);
535 #define BLKDBG_EVENT(child, evt) \
538 bdrv_debug_event(child->bs, evt); \
542 void bdrv_debug_event(BlockDriverState
*bs
, BlkdebugEvent event
);
544 int bdrv_debug_breakpoint(BlockDriverState
*bs
, const char *event
,
546 int bdrv_debug_remove_breakpoint(BlockDriverState
*bs
, const char *tag
);
547 int bdrv_debug_resume(BlockDriverState
*bs
, const char *tag
);
548 bool bdrv_debug_is_suspended(BlockDriverState
*bs
, const char *tag
);
551 * bdrv_get_aio_context:
553 * Returns: the currently bound #AioContext
555 AioContext
*bdrv_get_aio_context(BlockDriverState
*bs
);
558 * bdrv_set_aio_context:
560 * Changes the #AioContext used for fd handlers, timers, and BHs by this
561 * BlockDriverState and all its children.
563 * This function must be called with iothread lock held.
565 void bdrv_set_aio_context(BlockDriverState
*bs
, AioContext
*new_context
);
566 int bdrv_probe_blocksizes(BlockDriverState
*bs
, BlockSizes
*bsz
);
567 int bdrv_probe_geometry(BlockDriverState
*bs
, HDGeometry
*geo
);
569 void bdrv_io_plug(BlockDriverState
*bs
);
570 void bdrv_io_unplug(BlockDriverState
*bs
);
573 * bdrv_drained_begin:
575 * Begin a quiesced section for exclusive access to the BDS, by disabling
576 * external request sources including NBD server and device model. Note that
577 * this doesn't block timers or coroutines from submitting more requests, which
578 * means block_job_pause is still necessary.
580 * This function can be recursive.
582 void bdrv_drained_begin(BlockDriverState
*bs
);
587 * End a quiescent section started by bdrv_drained_begin().
589 void bdrv_drained_end(BlockDriverState
*bs
);
591 void bdrv_add_child(BlockDriverState
*parent
, BlockDriverState
*child
,
593 void bdrv_del_child(BlockDriverState
*parent
, BdrvChild
*child
, Error
**errp
);