5 #include "qapi/qapi-types-block-core.h"
6 #include "block/aio-wait.h"
8 #include "qemu/coroutine.h"
9 #include "block/accounting.h"
10 #include "block/dirty-bitmap.h"
11 #include "block/blockjob.h"
12 #include "qemu/hbitmap.h"
15 typedef struct BlockDriver BlockDriver
;
16 typedef struct BdrvChild BdrvChild
;
17 typedef struct BdrvChildRole BdrvChildRole
;
19 typedef struct BlockDriverInfo
{
20 /* in bytes, 0 if irrelevant */
22 /* offset at which the VM state can be saved (0 if not possible) */
23 int64_t vm_state_offset
;
26 * True if unallocated blocks read back as zeroes. This is equivalent
27 * to the LBPRZ flag in the SCSI logical block provisioning page.
29 bool unallocated_blocks_are_zero
;
31 * True if this block driver only supports compressed writes
33 bool needs_compressed_writes
;
36 typedef struct BlockFragInfo
{
37 uint64_t allocated_clusters
;
38 uint64_t total_clusters
;
39 uint64_t fragmented_clusters
;
40 uint64_t compressed_clusters
;
44 BDRV_REQ_COPY_ON_READ
= 0x1,
45 BDRV_REQ_ZERO_WRITE
= 0x2,
46 /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver
47 * is allowed to optimize a write zeroes request by unmapping (discarding)
48 * blocks if it is guaranteed that the result will read back as
49 * zeroes. The flag is only passed to the driver if the block device is
50 * opened with BDRV_O_UNMAP.
52 BDRV_REQ_MAY_UNMAP
= 0x4,
53 BDRV_REQ_NO_SERIALISING
= 0x8,
55 BDRV_REQ_WRITE_COMPRESSED
= 0x20,
57 /* Signifies that this write request will not change the visible disk
59 BDRV_REQ_WRITE_UNCHANGED
= 0x40,
61 /* Mask of valid flags */
65 typedef struct BlockSizes
{
70 typedef struct HDGeometry
{
76 #define BDRV_O_RDWR 0x0002
77 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */
78 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */
79 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */
80 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */
81 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */
82 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */
83 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */
84 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
85 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */
86 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */
87 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */
88 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */
89 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given:
90 select an appropriate protocol driver,
91 ignoring the format layer */
92 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */
94 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH)
97 /* Option names of options parsed by the block layer */
99 #define BDRV_OPT_CACHE_WB "cache.writeback"
100 #define BDRV_OPT_CACHE_DIRECT "cache.direct"
101 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush"
102 #define BDRV_OPT_READ_ONLY "read-only"
103 #define BDRV_OPT_DISCARD "discard"
104 #define BDRV_OPT_FORCE_SHARE "force-share"
107 #define BDRV_SECTOR_BITS 9
108 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS)
109 #define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1)
111 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \
112 INT_MAX >> BDRV_SECTOR_BITS)
113 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS)
116 * Allocation status flags for bdrv_block_status() and friends.
119 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer
120 * BDRV_BLOCK_ZERO: offset reads as zero
121 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data
122 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
123 * layer rather than any backing, set by block layer
124 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this
125 * layer, set by block layer
128 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request
129 * that the block layer recompute the answer from the returned
130 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID.
132 * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the
133 * host offset within the returned BDS that is allocated for the
134 * corresponding raw guest data. However, whether that offset
135 * actually contains data also depends on BDRV_BLOCK_DATA, as follows:
137 * DATA ZERO OFFSET_VALID
138 * t t t sectors read as zero, returned file is zero at offset
139 * t f t sectors read as valid from file at offset
140 * f t t sectors preallocated, read as zero, returned file not
141 * necessarily zero at offset
142 * f f t sectors preallocated but read from backing_hd,
143 * returned file contains garbage at offset
144 * t t f sectors preallocated, read as zero, unknown offset
145 * t f f sectors read from unknown file or offset
146 * f t f not allocated or unknown offset, read as zero
147 * f f f not allocated or unknown offset, read from backing_hd
149 #define BDRV_BLOCK_DATA 0x01
150 #define BDRV_BLOCK_ZERO 0x02
151 #define BDRV_BLOCK_OFFSET_VALID 0x04
152 #define BDRV_BLOCK_RAW 0x08
153 #define BDRV_BLOCK_ALLOCATED 0x10
154 #define BDRV_BLOCK_EOF 0x20
155 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK
157 typedef QSIMPLEQ_HEAD(BlockReopenQueue
, BlockReopenQueueEntry
) BlockReopenQueue
;
159 typedef struct BDRVReopenState
{
160 BlockDriverState
*bs
;
162 uint64_t perm
, shared_perm
;
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 * As the BLK_PERM_WRITE permission is strictly stronger, either is
214 * sufficient to perform an unchanging write.
216 BLK_PERM_WRITE_UNCHANGED
= 0x04,
218 /** This permission is required to change the size of a block node. */
219 BLK_PERM_RESIZE
= 0x08,
222 * This permission is required to change the node that this BdrvChild
225 BLK_PERM_GRAPH_MOD
= 0x10,
229 DEFAULT_PERM_PASSTHROUGH
= BLK_PERM_CONSISTENT_READ
231 | BLK_PERM_WRITE_UNCHANGED
234 DEFAULT_PERM_UNCHANGED
= BLK_PERM_ALL
& ~DEFAULT_PERM_PASSTHROUGH
,
237 char *bdrv_perm_names(uint64_t perm
);
239 /* disk I/O throttling */
240 void bdrv_init(void);
241 void bdrv_init_with_whitelist(void);
242 bool bdrv_uses_whitelist(void);
243 int bdrv_is_whitelisted(BlockDriver
*drv
, bool read_only
);
244 BlockDriver
*bdrv_find_protocol(const char *filename
,
245 bool allow_protocol_prefix
,
247 BlockDriver
*bdrv_find_format(const char *format_name
);
248 int bdrv_create(BlockDriver
*drv
, const char* filename
,
249 QemuOpts
*opts
, Error
**errp
);
250 int bdrv_create_file(const char *filename
, QemuOpts
*opts
, Error
**errp
);
251 BlockDriverState
*bdrv_new(void);
252 void bdrv_append(BlockDriverState
*bs_new
, BlockDriverState
*bs_top
,
254 void bdrv_replace_node(BlockDriverState
*from
, BlockDriverState
*to
,
257 int bdrv_parse_cache_mode(const char *mode
, int *flags
, bool *writethrough
);
258 int bdrv_parse_discard_flags(const char *mode
, int *flags
);
259 BdrvChild
*bdrv_open_child(const char *filename
,
260 QDict
*options
, const char *bdref_key
,
261 BlockDriverState
* parent
,
262 const BdrvChildRole
*child_role
,
263 bool allow_none
, Error
**errp
);
264 BlockDriverState
*bdrv_open_blockdev_ref(BlockdevRef
*ref
, Error
**errp
);
265 void bdrv_set_backing_hd(BlockDriverState
*bs
, BlockDriverState
*backing_hd
,
267 int bdrv_open_backing_file(BlockDriverState
*bs
, QDict
*parent_options
,
268 const char *bdref_key
, Error
**errp
);
269 BlockDriverState
*bdrv_open(const char *filename
, const char *reference
,
270 QDict
*options
, int flags
, Error
**errp
);
271 BlockDriverState
*bdrv_new_open_driver(BlockDriver
*drv
, const char *node_name
,
272 int flags
, Error
**errp
);
273 BlockReopenQueue
*bdrv_reopen_queue(BlockReopenQueue
*bs_queue
,
274 BlockDriverState
*bs
,
275 QDict
*options
, int flags
);
276 int bdrv_reopen_multiple(AioContext
*ctx
, BlockReopenQueue
*bs_queue
, Error
**errp
);
277 int bdrv_reopen(BlockDriverState
*bs
, int bdrv_flags
, Error
**errp
);
278 int bdrv_reopen_prepare(BDRVReopenState
*reopen_state
,
279 BlockReopenQueue
*queue
, Error
**errp
);
280 void bdrv_reopen_commit(BDRVReopenState
*reopen_state
);
281 void bdrv_reopen_abort(BDRVReopenState
*reopen_state
);
282 int bdrv_read(BdrvChild
*child
, int64_t sector_num
,
283 uint8_t *buf
, int nb_sectors
);
284 int bdrv_write(BdrvChild
*child
, int64_t sector_num
,
285 const uint8_t *buf
, int nb_sectors
);
286 int bdrv_pwrite_zeroes(BdrvChild
*child
, int64_t offset
,
287 int bytes
, BdrvRequestFlags flags
);
288 int bdrv_make_zero(BdrvChild
*child
, BdrvRequestFlags flags
);
289 int bdrv_pread(BdrvChild
*child
, int64_t offset
, void *buf
, int bytes
);
290 int bdrv_preadv(BdrvChild
*child
, int64_t offset
, QEMUIOVector
*qiov
);
291 int bdrv_pwrite(BdrvChild
*child
, int64_t offset
, const void *buf
, int bytes
);
292 int bdrv_pwritev(BdrvChild
*child
, int64_t offset
, QEMUIOVector
*qiov
);
293 int bdrv_pwrite_sync(BdrvChild
*child
, int64_t offset
,
294 const void *buf
, int count
);
296 * Efficiently zero a region of the disk image. Note that this is a regular
297 * I/O request like read or write and should have a reasonable size. This
298 * function is not suitable for zeroing the entire image in a single request
299 * because it may allocate memory for the entire region.
301 int coroutine_fn
bdrv_co_pwrite_zeroes(BdrvChild
*child
, int64_t offset
,
302 int bytes
, BdrvRequestFlags flags
);
303 BlockDriverState
*bdrv_find_backing_image(BlockDriverState
*bs
,
304 const char *backing_file
);
305 void bdrv_refresh_filename(BlockDriverState
*bs
);
307 int coroutine_fn
bdrv_co_truncate(BdrvChild
*child
, int64_t offset
,
308 PreallocMode prealloc
, Error
**errp
);
309 int bdrv_truncate(BdrvChild
*child
, int64_t offset
, PreallocMode prealloc
,
312 int64_t bdrv_nb_sectors(BlockDriverState
*bs
);
313 int64_t bdrv_getlength(BlockDriverState
*bs
);
314 int64_t bdrv_get_allocated_file_size(BlockDriverState
*bs
);
315 BlockMeasureInfo
*bdrv_measure(BlockDriver
*drv
, QemuOpts
*opts
,
316 BlockDriverState
*in_bs
, Error
**errp
);
317 void bdrv_get_geometry(BlockDriverState
*bs
, uint64_t *nb_sectors_ptr
);
318 void bdrv_refresh_limits(BlockDriverState
*bs
, Error
**errp
);
319 int bdrv_commit(BlockDriverState
*bs
);
320 int bdrv_change_backing_file(BlockDriverState
*bs
,
321 const char *backing_file
, const char *backing_fmt
);
322 void bdrv_register(BlockDriver
*bdrv
);
323 int bdrv_drop_intermediate(BlockDriverState
*top
, BlockDriverState
*base
,
324 const char *backing_file_str
);
325 BlockDriverState
*bdrv_find_overlay(BlockDriverState
*active
,
326 BlockDriverState
*bs
);
327 BlockDriverState
*bdrv_find_base(BlockDriverState
*bs
);
330 typedef struct BdrvCheckResult
{
334 int corruptions_fixed
;
336 int64_t image_end_offset
;
345 int bdrv_check(BlockDriverState
*bs
, BdrvCheckResult
*res
, BdrvCheckMode fix
);
347 /* The units of offset and total_work_size may be chosen arbitrarily by the
348 * block driver; total_work_size may change during the course of the amendment
350 typedef void BlockDriverAmendStatusCB(BlockDriverState
*bs
, int64_t offset
,
351 int64_t total_work_size
, void *opaque
);
352 int bdrv_amend_options(BlockDriverState
*bs_new
, QemuOpts
*opts
,
353 BlockDriverAmendStatusCB
*status_cb
, void *cb_opaque
,
356 /* external snapshots */
357 bool bdrv_recurse_is_first_non_filter(BlockDriverState
*bs
,
358 BlockDriverState
*candidate
);
359 bool bdrv_is_first_non_filter(BlockDriverState
*candidate
);
361 /* check if a named node can be replaced when doing drive-mirror */
362 BlockDriverState
*check_to_replace_node(BlockDriverState
*parent_bs
,
363 const char *node_name
, Error
**errp
);
365 /* async block I/O */
366 void bdrv_aio_cancel(BlockAIOCB
*acb
);
367 void bdrv_aio_cancel_async(BlockAIOCB
*acb
);
369 /* sg packet commands */
370 int bdrv_co_ioctl(BlockDriverState
*bs
, int req
, void *buf
);
372 /* Invalidate any cached metadata used by image formats */
373 void bdrv_invalidate_cache(BlockDriverState
*bs
, Error
**errp
);
374 void bdrv_invalidate_cache_all(Error
**errp
);
375 int bdrv_inactivate_all(void);
377 /* Ensure contents are flushed to disk. */
378 int bdrv_flush(BlockDriverState
*bs
);
379 int coroutine_fn
bdrv_co_flush(BlockDriverState
*bs
);
380 int bdrv_flush_all(void);
381 void bdrv_close_all(void);
382 void bdrv_drain(BlockDriverState
*bs
);
383 void coroutine_fn
bdrv_co_drain(BlockDriverState
*bs
);
384 void bdrv_drain_all_begin(void);
385 void bdrv_drain_all_end(void);
386 void bdrv_drain_all(void);
388 /* Returns NULL when bs == NULL */
389 AioWait
*bdrv_get_aio_wait(BlockDriverState
*bs
);
391 #define BDRV_POLL_WHILE(bs, cond) ({ \
392 BlockDriverState *bs_ = (bs); \
393 AIO_WAIT_WHILE(bdrv_get_aio_wait(bs_), \
394 bdrv_get_aio_context(bs_), \
397 int bdrv_pdiscard(BlockDriverState
*bs
, int64_t offset
, int bytes
);
398 int bdrv_co_pdiscard(BlockDriverState
*bs
, int64_t offset
, int bytes
);
399 int bdrv_has_zero_init_1(BlockDriverState
*bs
);
400 int bdrv_has_zero_init(BlockDriverState
*bs
);
401 bool bdrv_unallocated_blocks_are_zero(BlockDriverState
*bs
);
402 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState
*bs
);
403 int bdrv_block_status(BlockDriverState
*bs
, int64_t offset
,
404 int64_t bytes
, int64_t *pnum
, int64_t *map
,
405 BlockDriverState
**file
);
406 int bdrv_block_status_above(BlockDriverState
*bs
, BlockDriverState
*base
,
407 int64_t offset
, int64_t bytes
, int64_t *pnum
,
408 int64_t *map
, BlockDriverState
**file
);
409 int bdrv_is_allocated(BlockDriverState
*bs
, int64_t offset
, int64_t bytes
,
411 int bdrv_is_allocated_above(BlockDriverState
*top
, BlockDriverState
*base
,
412 int64_t offset
, int64_t bytes
, int64_t *pnum
);
414 bool bdrv_is_read_only(BlockDriverState
*bs
);
415 int bdrv_can_set_read_only(BlockDriverState
*bs
, bool read_only
,
416 bool ignore_allow_rdw
, Error
**errp
);
417 int bdrv_set_read_only(BlockDriverState
*bs
, bool read_only
, Error
**errp
);
418 bool bdrv_is_writable(BlockDriverState
*bs
);
419 bool bdrv_is_sg(BlockDriverState
*bs
);
420 bool bdrv_is_inserted(BlockDriverState
*bs
);
421 void bdrv_lock_medium(BlockDriverState
*bs
, bool locked
);
422 void bdrv_eject(BlockDriverState
*bs
, bool eject_flag
);
423 const char *bdrv_get_format_name(BlockDriverState
*bs
);
424 BlockDriverState
*bdrv_find_node(const char *node_name
);
425 BlockDeviceInfoList
*bdrv_named_nodes_list(Error
**errp
);
426 BlockDriverState
*bdrv_lookup_bs(const char *device
,
427 const char *node_name
,
429 bool bdrv_chain_contains(BlockDriverState
*top
, BlockDriverState
*base
);
430 BlockDriverState
*bdrv_next_node(BlockDriverState
*bs
);
431 BlockDriverState
*bdrv_next_all_states(BlockDriverState
*bs
);
433 typedef struct BdrvNextIterator
{
435 BDRV_NEXT_BACKEND_ROOTS
,
436 BDRV_NEXT_MONITOR_OWNED
,
439 BlockDriverState
*bs
;
442 BlockDriverState
*bdrv_first(BdrvNextIterator
*it
);
443 BlockDriverState
*bdrv_next(BdrvNextIterator
*it
);
444 void bdrv_next_cleanup(BdrvNextIterator
*it
);
446 BlockDriverState
*bdrv_next_monitor_owned(BlockDriverState
*bs
);
447 bool bdrv_is_encrypted(BlockDriverState
*bs
);
448 void bdrv_iterate_format(void (*it
)(void *opaque
, const char *name
),
450 const char *bdrv_get_node_name(const BlockDriverState
*bs
);
451 const char *bdrv_get_device_name(const BlockDriverState
*bs
);
452 const char *bdrv_get_device_or_node_name(const BlockDriverState
*bs
);
453 int bdrv_get_flags(BlockDriverState
*bs
);
454 int bdrv_get_info(BlockDriverState
*bs
, BlockDriverInfo
*bdi
);
455 ImageInfoSpecific
*bdrv_get_specific_info(BlockDriverState
*bs
);
456 void bdrv_round_to_clusters(BlockDriverState
*bs
,
457 int64_t offset
, int64_t bytes
,
458 int64_t *cluster_offset
,
459 int64_t *cluster_bytes
);
461 const char *bdrv_get_encrypted_filename(BlockDriverState
*bs
);
462 void bdrv_get_backing_filename(BlockDriverState
*bs
,
463 char *filename
, int filename_size
);
464 void bdrv_get_full_backing_filename(BlockDriverState
*bs
,
465 char *dest
, size_t sz
, Error
**errp
);
466 void bdrv_get_full_backing_filename_from_filename(const char *backed
,
468 char *dest
, size_t sz
,
471 int path_has_protocol(const char *path
);
472 int path_is_absolute(const char *path
);
473 void path_combine(char *dest
, int dest_size
,
474 const char *base_path
,
475 const char *filename
);
477 int bdrv_readv_vmstate(BlockDriverState
*bs
, QEMUIOVector
*qiov
, int64_t pos
);
478 int bdrv_writev_vmstate(BlockDriverState
*bs
, QEMUIOVector
*qiov
, int64_t pos
);
479 int bdrv_save_vmstate(BlockDriverState
*bs
, const uint8_t *buf
,
480 int64_t pos
, int size
);
482 int bdrv_load_vmstate(BlockDriverState
*bs
, uint8_t *buf
,
483 int64_t pos
, int size
);
485 void bdrv_img_create(const char *filename
, const char *fmt
,
486 const char *base_filename
, const char *base_fmt
,
487 char *options
, uint64_t img_size
, int flags
,
488 bool quiet
, Error
**errp
);
490 /* Returns the alignment in bytes that is required so that no bounce buffer
491 * is required throughout the stack */
492 size_t bdrv_min_mem_align(BlockDriverState
*bs
);
493 /* Returns optimal alignment in bytes for bounce buffer */
494 size_t bdrv_opt_mem_align(BlockDriverState
*bs
);
495 void *qemu_blockalign(BlockDriverState
*bs
, size_t size
);
496 void *qemu_blockalign0(BlockDriverState
*bs
, size_t size
);
497 void *qemu_try_blockalign(BlockDriverState
*bs
, size_t size
);
498 void *qemu_try_blockalign0(BlockDriverState
*bs
, size_t size
);
499 bool bdrv_qiov_is_aligned(BlockDriverState
*bs
, QEMUIOVector
*qiov
);
501 void bdrv_enable_copy_on_read(BlockDriverState
*bs
);
502 void bdrv_disable_copy_on_read(BlockDriverState
*bs
);
504 void bdrv_ref(BlockDriverState
*bs
);
505 void bdrv_unref(BlockDriverState
*bs
);
506 void bdrv_unref_child(BlockDriverState
*parent
, BdrvChild
*child
);
507 BdrvChild
*bdrv_attach_child(BlockDriverState
*parent_bs
,
508 BlockDriverState
*child_bs
,
509 const char *child_name
,
510 const BdrvChildRole
*child_role
,
513 bool bdrv_op_is_blocked(BlockDriverState
*bs
, BlockOpType op
, Error
**errp
);
514 void bdrv_op_block(BlockDriverState
*bs
, BlockOpType op
, Error
*reason
);
515 void bdrv_op_unblock(BlockDriverState
*bs
, BlockOpType op
, Error
*reason
);
516 void bdrv_op_block_all(BlockDriverState
*bs
, Error
*reason
);
517 void bdrv_op_unblock_all(BlockDriverState
*bs
, Error
*reason
);
518 bool bdrv_op_blocker_is_empty(BlockDriverState
*bs
);
520 #define BLKDBG_EVENT(child, evt) \
523 bdrv_debug_event(child->bs, evt); \
527 void bdrv_debug_event(BlockDriverState
*bs
, BlkdebugEvent event
);
529 int bdrv_debug_breakpoint(BlockDriverState
*bs
, const char *event
,
531 int bdrv_debug_remove_breakpoint(BlockDriverState
*bs
, const char *tag
);
532 int bdrv_debug_resume(BlockDriverState
*bs
, const char *tag
);
533 bool bdrv_debug_is_suspended(BlockDriverState
*bs
, const char *tag
);
536 * bdrv_get_aio_context:
538 * Returns: the currently bound #AioContext
540 AioContext
*bdrv_get_aio_context(BlockDriverState
*bs
);
543 * Transfer control to @co in the aio context of @bs
545 void bdrv_coroutine_enter(BlockDriverState
*bs
, Coroutine
*co
);
548 * bdrv_set_aio_context:
550 * Changes the #AioContext used for fd handlers, timers, and BHs by this
551 * BlockDriverState and all its children.
553 * This function must be called with iothread lock held.
555 void bdrv_set_aio_context(BlockDriverState
*bs
, AioContext
*new_context
);
556 int bdrv_probe_blocksizes(BlockDriverState
*bs
, BlockSizes
*bsz
);
557 int bdrv_probe_geometry(BlockDriverState
*bs
, HDGeometry
*geo
);
559 void bdrv_io_plug(BlockDriverState
*bs
);
560 void bdrv_io_unplug(BlockDriverState
*bs
);
563 * bdrv_parent_drained_begin:
565 * Begin a quiesced section of all users of @bs. This is part of
566 * bdrv_drained_begin.
568 void bdrv_parent_drained_begin(BlockDriverState
*bs
, BdrvChild
*ignore
,
569 bool ignore_bds_parents
);
572 * bdrv_parent_drained_end:
574 * End a quiesced section of all users of @bs. This is part of
577 void bdrv_parent_drained_end(BlockDriverState
*bs
, BdrvChild
*ignore
,
578 bool ignore_bds_parents
);
583 * Poll for pending requests in @bs, its parents (except for @ignore_parent),
584 * and if @recursive is true its children as well (used for subtree drain).
586 * If @ignore_bds_parents is true, parents that are BlockDriverStates must
587 * ignore the drain request because they will be drained separately (used for
590 * This is part of bdrv_drained_begin.
592 bool bdrv_drain_poll(BlockDriverState
*bs
, bool recursive
,
593 BdrvChild
*ignore_parent
, bool ignore_bds_parents
);
596 * bdrv_drained_begin:
598 * Begin a quiesced section for exclusive access to the BDS, by disabling
599 * external request sources including NBD server and device model. Note that
600 * this doesn't block timers or coroutines from submitting more requests, which
601 * means block_job_pause is still necessary.
603 * This function can be recursive.
605 void bdrv_drained_begin(BlockDriverState
*bs
);
608 * bdrv_do_drained_begin_quiesce:
610 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already
611 * running requests to complete.
613 void bdrv_do_drained_begin_quiesce(BlockDriverState
*bs
,
614 BdrvChild
*parent
, bool ignore_bds_parents
);
617 * Like bdrv_drained_begin, but recursively begins a quiesced section for
618 * exclusive access to all child nodes as well.
620 void bdrv_subtree_drained_begin(BlockDriverState
*bs
);
625 * End a quiescent section started by bdrv_drained_begin().
627 void bdrv_drained_end(BlockDriverState
*bs
);
630 * End a quiescent section started by bdrv_subtree_drained_begin().
632 void bdrv_subtree_drained_end(BlockDriverState
*bs
);
634 void bdrv_add_child(BlockDriverState
*parent
, BlockDriverState
*child
,
636 void bdrv_del_child(BlockDriverState
*parent
, BdrvChild
*child
, Error
**errp
);
638 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState
*bs
, const char *name
,
639 uint32_t granularity
, Error
**errp
);
642 * bdrv_register_buf/bdrv_unregister_buf:
644 * Register/unregister a buffer for I/O. For example, VFIO drivers are
645 * interested to know the memory areas that would later be used for I/O, so
646 * that they can prepare IOMMU mapping etc., to get better performance.
648 void bdrv_register_buf(BlockDriverState
*bs
, void *host
, size_t size
);
649 void bdrv_unregister_buf(BlockDriverState
*bs
, void *host
);
653 * bdrv_co_copy_range:
655 * Do offloaded copy between two children. If the operation is not implemented
656 * by the driver, or if the backend storage doesn't support it, a negative
657 * error code will be returned.
659 * Note: block layer doesn't emulate or fallback to a bounce buffer approach
660 * because usually the caller shouldn't attempt offloaded copy any more (e.g.
661 * calling copy_file_range(2)) after the first error, thus it should fall back
662 * to a read+write path in the caller level.
664 * @src: Source child to copy data from
665 * @src_offset: offset in @src image to read data
666 * @dst: Destination child to copy data to
667 * @dst_offset: offset in @dst image to write data
668 * @bytes: number of bytes to copy
669 * @flags: request flags. Supported flags:
670 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero
671 * write on @dst as if bdrv_co_pwrite_zeroes is
672 * called. Used to simplify caller code, or
673 * during BlockDriver.bdrv_co_copy_range_from()
675 * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping
676 * requests currently in flight.
678 * Returns: 0 if succeeded; negative error code if failed.
680 int coroutine_fn
bdrv_co_copy_range(BdrvChild
*src
, uint64_t src_offset
,
681 BdrvChild
*dst
, uint64_t dst_offset
,
682 uint64_t bytes
, BdrvRequestFlags flags
);