2 * QEMU System Emulator block driver
4 * Copyright (c) 2003 Fabrice Bellard
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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
27 #include "block/accounting.h"
28 #include "block/block.h"
29 #include "block/throttle-groups.h"
30 #include "qemu/option.h"
31 #include "qemu/queue.h"
32 #include "qemu/coroutine.h"
33 #include "qemu/timer.h"
34 #include "qapi-types.h"
35 #include "qemu/hbitmap.h"
36 #include "block/snapshot.h"
37 #include "qemu/main-loop.h"
38 #include "qemu/throttle.h"
40 #define BLOCK_FLAG_ENCRYPT 1
41 #define BLOCK_FLAG_COMPAT6 4
42 #define BLOCK_FLAG_LAZY_REFCOUNTS 8
44 #define BLOCK_OPT_SIZE "size"
45 #define BLOCK_OPT_ENCRYPT "encryption"
46 #define BLOCK_OPT_COMPAT6 "compat6"
47 #define BLOCK_OPT_BACKING_FILE "backing_file"
48 #define BLOCK_OPT_BACKING_FMT "backing_fmt"
49 #define BLOCK_OPT_CLUSTER_SIZE "cluster_size"
50 #define BLOCK_OPT_TABLE_SIZE "table_size"
51 #define BLOCK_OPT_PREALLOC "preallocation"
52 #define BLOCK_OPT_SUBFMT "subformat"
53 #define BLOCK_OPT_COMPAT_LEVEL "compat"
54 #define BLOCK_OPT_LAZY_REFCOUNTS "lazy_refcounts"
55 #define BLOCK_OPT_ADAPTER_TYPE "adapter_type"
56 #define BLOCK_OPT_REDUNDANCY "redundancy"
57 #define BLOCK_OPT_NOCOW "nocow"
58 #define BLOCK_OPT_OBJECT_SIZE "object_size"
59 #define BLOCK_OPT_REFCOUNT_BITS "refcount_bits"
61 #define BLOCK_PROBE_BUF_SIZE 512
63 typedef struct BdrvTrackedRequest
{
70 int64_t overlap_offset
;
71 unsigned int overlap_bytes
;
73 QLIST_ENTRY(BdrvTrackedRequest
) list
;
74 Coroutine
*co
; /* owner, used for deadlock detection */
75 CoQueue wait_queue
; /* coroutines blocked on this request */
77 struct BdrvTrackedRequest
*waiting_for
;
81 const char *format_name
;
84 /* set to true if the BlockDriver is a block filter */
86 /* for snapshots block filter like Quorum can implement the
87 * following recursive callback.
88 * It's purpose is to recurse on the filter children while calling
89 * bdrv_recurse_is_first_non_filter on them.
90 * For a sample implementation look in the future Quorum block filter.
92 bool (*bdrv_recurse_is_first_non_filter
)(BlockDriverState
*bs
,
93 BlockDriverState
*candidate
);
95 int (*bdrv_probe
)(const uint8_t *buf
, int buf_size
, const char *filename
);
96 int (*bdrv_probe_device
)(const char *filename
);
98 /* Any driver implementing this callback is expected to be able to handle
99 * NULL file names in its .bdrv_open() implementation */
100 void (*bdrv_parse_filename
)(const char *filename
, QDict
*options
, Error
**errp
);
101 /* Drivers not implementing bdrv_parse_filename nor bdrv_open should have
102 * this field set to true, except ones that are defined only by their
104 * An example of the last type will be the quorum block driver.
106 bool bdrv_needs_filename
;
108 /* Set if a driver can support backing files */
109 bool supports_backing
;
111 /* For handling image reopen for split or non-split files */
112 int (*bdrv_reopen_prepare
)(BDRVReopenState
*reopen_state
,
113 BlockReopenQueue
*queue
, Error
**errp
);
114 void (*bdrv_reopen_commit
)(BDRVReopenState
*reopen_state
);
115 void (*bdrv_reopen_abort
)(BDRVReopenState
*reopen_state
);
117 int (*bdrv_open
)(BlockDriverState
*bs
, QDict
*options
, int flags
,
119 int (*bdrv_file_open
)(BlockDriverState
*bs
, QDict
*options
, int flags
,
121 int (*bdrv_read
)(BlockDriverState
*bs
, int64_t sector_num
,
122 uint8_t *buf
, int nb_sectors
);
123 int (*bdrv_write
)(BlockDriverState
*bs
, int64_t sector_num
,
124 const uint8_t *buf
, int nb_sectors
);
125 void (*bdrv_close
)(BlockDriverState
*bs
);
126 int (*bdrv_create
)(const char *filename
, QemuOpts
*opts
, Error
**errp
);
127 int (*bdrv_set_key
)(BlockDriverState
*bs
, const char *key
);
128 int (*bdrv_make_empty
)(BlockDriverState
*bs
);
130 void (*bdrv_refresh_filename
)(BlockDriverState
*bs
);
133 BlockAIOCB
*(*bdrv_aio_readv
)(BlockDriverState
*bs
,
134 int64_t sector_num
, QEMUIOVector
*qiov
, int nb_sectors
,
135 BlockCompletionFunc
*cb
, void *opaque
);
136 BlockAIOCB
*(*bdrv_aio_writev
)(BlockDriverState
*bs
,
137 int64_t sector_num
, QEMUIOVector
*qiov
, int nb_sectors
,
138 BlockCompletionFunc
*cb
, void *opaque
);
139 BlockAIOCB
*(*bdrv_aio_flush
)(BlockDriverState
*bs
,
140 BlockCompletionFunc
*cb
, void *opaque
);
141 BlockAIOCB
*(*bdrv_aio_discard
)(BlockDriverState
*bs
,
142 int64_t sector_num
, int nb_sectors
,
143 BlockCompletionFunc
*cb
, void *opaque
);
145 int coroutine_fn (*bdrv_co_readv
)(BlockDriverState
*bs
,
146 int64_t sector_num
, int nb_sectors
, QEMUIOVector
*qiov
);
147 int coroutine_fn (*bdrv_co_writev
)(BlockDriverState
*bs
,
148 int64_t sector_num
, int nb_sectors
, QEMUIOVector
*qiov
);
150 * Efficiently zero a region of the disk image. Typically an image format
151 * would use a compact metadata representation to implement this. This
152 * function pointer may be NULL and .bdrv_co_writev() will be called
155 int coroutine_fn (*bdrv_co_write_zeroes
)(BlockDriverState
*bs
,
156 int64_t sector_num
, int nb_sectors
, BdrvRequestFlags flags
);
157 int coroutine_fn (*bdrv_co_discard
)(BlockDriverState
*bs
,
158 int64_t sector_num
, int nb_sectors
);
159 int64_t coroutine_fn (*bdrv_co_get_block_status
)(BlockDriverState
*bs
,
160 int64_t sector_num
, int nb_sectors
, int *pnum
);
163 * Invalidate any cached meta-data.
165 void (*bdrv_invalidate_cache
)(BlockDriverState
*bs
, Error
**errp
);
168 * Flushes all data that was already written to the OS all the way down to
169 * the disk (for example raw-posix calls fsync()).
171 int coroutine_fn (*bdrv_co_flush_to_disk
)(BlockDriverState
*bs
);
174 * Flushes all internal caches to the OS. The data may still sit in a
175 * writeback cache of the host OS, but it will survive a crash of the qemu
178 int coroutine_fn (*bdrv_co_flush_to_os
)(BlockDriverState
*bs
);
180 const char *protocol_name
;
181 int (*bdrv_truncate
)(BlockDriverState
*bs
, int64_t offset
);
183 int64_t (*bdrv_getlength
)(BlockDriverState
*bs
);
184 bool has_variable_length
;
185 int64_t (*bdrv_get_allocated_file_size
)(BlockDriverState
*bs
);
187 int (*bdrv_write_compressed
)(BlockDriverState
*bs
, int64_t sector_num
,
188 const uint8_t *buf
, int nb_sectors
);
190 int (*bdrv_snapshot_create
)(BlockDriverState
*bs
,
191 QEMUSnapshotInfo
*sn_info
);
192 int (*bdrv_snapshot_goto
)(BlockDriverState
*bs
,
193 const char *snapshot_id
);
194 int (*bdrv_snapshot_delete
)(BlockDriverState
*bs
,
195 const char *snapshot_id
,
198 int (*bdrv_snapshot_list
)(BlockDriverState
*bs
,
199 QEMUSnapshotInfo
**psn_info
);
200 int (*bdrv_snapshot_load_tmp
)(BlockDriverState
*bs
,
201 const char *snapshot_id
,
204 int (*bdrv_get_info
)(BlockDriverState
*bs
, BlockDriverInfo
*bdi
);
205 ImageInfoSpecific
*(*bdrv_get_specific_info
)(BlockDriverState
*bs
);
207 int (*bdrv_save_vmstate
)(BlockDriverState
*bs
, QEMUIOVector
*qiov
,
209 int (*bdrv_load_vmstate
)(BlockDriverState
*bs
, uint8_t *buf
,
210 int64_t pos
, int size
);
212 int (*bdrv_change_backing_file
)(BlockDriverState
*bs
,
213 const char *backing_file
, const char *backing_fmt
);
215 /* removable device specific */
216 bool (*bdrv_is_inserted
)(BlockDriverState
*bs
);
217 int (*bdrv_media_changed
)(BlockDriverState
*bs
);
218 void (*bdrv_eject
)(BlockDriverState
*bs
, bool eject_flag
);
219 void (*bdrv_lock_medium
)(BlockDriverState
*bs
, bool locked
);
221 /* to control generic scsi devices */
222 int (*bdrv_ioctl
)(BlockDriverState
*bs
, unsigned long int req
, void *buf
);
223 BlockAIOCB
*(*bdrv_aio_ioctl
)(BlockDriverState
*bs
,
224 unsigned long int req
, void *buf
,
225 BlockCompletionFunc
*cb
, void *opaque
);
227 /* List of options for creating images, terminated by name == NULL */
228 QemuOptsList
*create_opts
;
231 * Returns 0 for completed check, -errno for internal errors.
232 * The check results are stored in result.
234 int (*bdrv_check
)(BlockDriverState
* bs
, BdrvCheckResult
*result
,
237 int (*bdrv_amend_options
)(BlockDriverState
*bs
, QemuOpts
*opts
,
238 BlockDriverAmendStatusCB
*status_cb
);
240 void (*bdrv_debug_event
)(BlockDriverState
*bs
, BlkDebugEvent event
);
242 /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */
243 int (*bdrv_debug_breakpoint
)(BlockDriverState
*bs
, const char *event
,
245 int (*bdrv_debug_remove_breakpoint
)(BlockDriverState
*bs
,
247 int (*bdrv_debug_resume
)(BlockDriverState
*bs
, const char *tag
);
248 bool (*bdrv_debug_is_suspended
)(BlockDriverState
*bs
, const char *tag
);
250 void (*bdrv_refresh_limits
)(BlockDriverState
*bs
, Error
**errp
);
253 * Returns 1 if newly created images are guaranteed to contain only
254 * zeros, 0 otherwise.
256 int (*bdrv_has_zero_init
)(BlockDriverState
*bs
);
258 /* Remove fd handlers, timers, and other event loop callbacks so the event
259 * loop is no longer in use. Called with no in-flight requests and in
260 * depth-first traversal order with parents before child nodes.
262 void (*bdrv_detach_aio_context
)(BlockDriverState
*bs
);
264 /* Add fd handlers, timers, and other event loop callbacks so I/O requests
265 * can be processed again. Called with no in-flight requests and in
266 * depth-first traversal order with child nodes before parent nodes.
268 void (*bdrv_attach_aio_context
)(BlockDriverState
*bs
,
269 AioContext
*new_context
);
271 /* io queue for linux-aio */
272 void (*bdrv_io_plug
)(BlockDriverState
*bs
);
273 void (*bdrv_io_unplug
)(BlockDriverState
*bs
);
274 void (*bdrv_flush_io_queue
)(BlockDriverState
*bs
);
277 * Try to get @bs's logical and physical block size.
278 * On success, store them in @bsz and return zero.
279 * On failure, return negative errno.
281 int (*bdrv_probe_blocksizes
)(BlockDriverState
*bs
, BlockSizes
*bsz
);
283 * Try to get @bs's geometry (cyls, heads, sectors)
284 * On success, store them in @geo and return 0.
285 * On failure return -errno.
286 * Only drivers that want to override guest geometry implement this
287 * callback; see hd_geometry_guess().
289 int (*bdrv_probe_geometry
)(BlockDriverState
*bs
, HDGeometry
*geo
);
291 QLIST_ENTRY(BlockDriver
) list
;
294 typedef struct BlockLimits
{
295 /* maximum number of sectors that can be discarded at once */
298 /* optimal alignment for discard requests in sectors */
299 int64_t discard_alignment
;
301 /* maximum number of sectors that can zeroized at once */
302 int max_write_zeroes
;
304 /* optimal alignment for write zeroes requests in sectors */
305 int64_t write_zeroes_alignment
;
307 /* optimal transfer length in sectors */
308 int opt_transfer_length
;
310 /* maximal transfer length in sectors */
311 int max_transfer_length
;
313 /* memory alignment so that no bounce buffer is needed */
314 size_t min_mem_alignment
;
316 /* memory alignment for bounce buffer */
317 size_t opt_mem_alignment
;
320 typedef struct BdrvOpBlocker BdrvOpBlocker
;
322 typedef struct BdrvAioNotifier
{
323 void (*attached_aio_context
)(AioContext
*new_context
, void *opaque
);
324 void (*detach_aio_context
)(void *opaque
);
328 QLIST_ENTRY(BdrvAioNotifier
) list
;
331 struct BdrvChildRole
{
332 int (*inherit_flags
)(int parent_flags
);
335 extern const BdrvChildRole child_file
;
336 extern const BdrvChildRole child_format
;
339 BlockDriverState
*bs
;
340 const BdrvChildRole
*role
;
341 QLIST_ENTRY(BdrvChild
) next
;
342 QLIST_ENTRY(BdrvChild
) next_parent
;
346 * Note: the function bdrv_append() copies and swaps contents of
347 * BlockDriverStates, so if you add new fields to this struct, please
348 * inspect bdrv_append() to determine if the new fields need to be
351 struct BlockDriverState
{
352 int64_t total_sectors
; /* if we are reading a disk image, give its
354 int read_only
; /* if true, the media is read only */
355 int open_flags
; /* flags used to open the file, re-used for re-open */
356 int encrypted
; /* if true, the media is encrypted */
357 int valid_key
; /* if true, a valid encryption key has been set */
358 int sg
; /* if true, the device is a /dev/sg* */
359 int copy_on_read
; /* if true, copy read backing sectors into image
360 note this is a reference count */
363 BlockDriver
*drv
; /* NULL means no media */
366 BlockBackend
*blk
; /* owning backend, if any */
368 AioContext
*aio_context
; /* event loop used for fd handlers, timers, etc */
369 /* long-running tasks intended to always use the same AioContext as this
370 * BDS may register themselves in this list to be notified of changes
371 * regarding this BDS's context */
372 QLIST_HEAD(, BdrvAioNotifier
) aio_notifiers
;
374 char filename
[PATH_MAX
];
375 char backing_file
[PATH_MAX
]; /* if non zero, the image is a diff of
377 char backing_format
[16]; /* if non-zero and backing_file exists */
379 QDict
*full_open_options
;
380 char exact_filename
[PATH_MAX
];
385 NotifierList close_notifiers
;
387 /* Callback before write request is processed */
388 NotifierWithReturnList before_write_notifiers
;
390 /* number of in-flight serialising requests */
391 unsigned int serialising_in_flight
;
394 CoQueue throttled_reqs
[2];
395 bool io_limits_enabled
;
396 /* The following fields are protected by the ThrottleGroup lock.
397 * See the ThrottleGroup documentation for details. */
398 ThrottleState
*throttle_state
;
399 ThrottleTimers throttle_timers
;
400 unsigned pending_reqs
[2];
401 QLIST_ENTRY(BlockDriverState
) round_robin
;
403 /* Offset after the highest byte written to */
404 uint64_t wr_highest_offset
;
409 /* Whether produces zeros when read beyond eof */
410 bool zero_beyond_eof
;
412 /* Alignment requirement for offset/length of I/O requests */
413 unsigned int request_alignment
;
415 /* do we need to tell the quest if we have a volatile write cache? */
416 int enable_write_cache
;
418 /* the following member gives a name to every node on the bs graph. */
420 /* element of the list of named nodes building the graph */
421 QTAILQ_ENTRY(BlockDriverState
) node_list
;
422 /* element of the list of "drives" the guest sees */
423 QTAILQ_ENTRY(BlockDriverState
) device_list
;
424 QLIST_HEAD(, BdrvDirtyBitmap
) dirty_bitmaps
;
427 QLIST_HEAD(, BdrvTrackedRequest
) tracked_requests
;
429 /* operation blockers */
430 QLIST_HEAD(, BdrvOpBlocker
) op_blockers
[BLOCK_OP_TYPE_MAX
];
432 /* long-running background operation */
435 /* The node that this node inherited default options from (and a reopen on
436 * which can affect this node by changing these defaults). This is always a
437 * parent node of this node. */
438 BlockDriverState
*inherits_from
;
439 QLIST_HEAD(, BdrvChild
) children
;
440 QLIST_HEAD(, BdrvChild
) parents
;
443 BlockdevDetectZeroesOptions detect_zeroes
;
445 /* The error object in use for blocking operations on backing_hd */
446 Error
*backing_blocker
;
448 /* threshold limit for writes, in bytes. "High water mark". */
449 uint64_t write_threshold_offset
;
450 NotifierWithReturn write_threshold_notifier
;
455 struct BlockBackendRootState
{
458 BlockdevDetectZeroesOptions detect_zeroes
;
460 char *throttle_group
;
461 ThrottleState
*throttle_state
;
464 static inline BlockDriverState
*backing_bs(BlockDriverState
*bs
)
466 return bs
->backing
? bs
->backing
->bs
: NULL
;
470 /* Essential block drivers which must always be statically linked into qemu, and
471 * which therefore can be accessed without using bdrv_find_format() */
472 extern BlockDriver bdrv_file
;
473 extern BlockDriver bdrv_raw
;
474 extern BlockDriver bdrv_qcow2
;
477 * bdrv_setup_io_funcs:
479 * Prepare a #BlockDriver for I/O request processing by populating
480 * unimplemented coroutine and AIO interfaces with generic wrapper functions
481 * that fall back to implemented interfaces.
483 void bdrv_setup_io_funcs(BlockDriver
*bdrv
);
485 int get_tmp_filename(char *filename
, int size
);
486 BlockDriver
*bdrv_probe_all(const uint8_t *buf
, int buf_size
,
487 const char *filename
);
489 void bdrv_set_io_limits(BlockDriverState
*bs
,
490 ThrottleConfig
*cfg
);
494 * bdrv_add_before_write_notifier:
496 * Register a callback that is invoked before write requests are processed but
497 * after any throttling or waiting for overlapping requests.
499 void bdrv_add_before_write_notifier(BlockDriverState
*bs
,
500 NotifierWithReturn
*notifier
);
503 * bdrv_detach_aio_context:
505 * May be called from .bdrv_detach_aio_context() to detach children from the
506 * current #AioContext. This is only needed by block drivers that manage their
507 * own children. Both ->file and ->backing are automatically handled and
508 * block drivers should not call this function on them explicitly.
510 void bdrv_detach_aio_context(BlockDriverState
*bs
);
513 * bdrv_attach_aio_context:
515 * May be called from .bdrv_attach_aio_context() to attach children to the new
516 * #AioContext. This is only needed by block drivers that manage their own
517 * children. Both ->file and ->backing are automatically handled and block
518 * drivers should not call this function on them explicitly.
520 void bdrv_attach_aio_context(BlockDriverState
*bs
,
521 AioContext
*new_context
);
524 * bdrv_add_aio_context_notifier:
526 * If a long-running job intends to be always run in the same AioContext as a
527 * certain BDS, it may use this function to be notified of changes regarding the
528 * association of the BDS to an AioContext.
530 * attached_aio_context() is called after the target BDS has been attached to a
531 * new AioContext; detach_aio_context() is called before the target BDS is being
532 * detached from its old AioContext.
534 void bdrv_add_aio_context_notifier(BlockDriverState
*bs
,
535 void (*attached_aio_context
)(AioContext
*new_context
, void *opaque
),
536 void (*detach_aio_context
)(void *opaque
), void *opaque
);
539 * bdrv_remove_aio_context_notifier:
541 * Unsubscribe of change notifications regarding the BDS's AioContext. The
542 * parameters given here have to be the same as those given to
543 * bdrv_add_aio_context_notifier().
545 void bdrv_remove_aio_context_notifier(BlockDriverState
*bs
,
546 void (*aio_context_attached
)(AioContext
*,
548 void (*aio_context_detached
)(void *),
552 int is_windows_drive(const char *filename
);
557 * @bs: Block device to operate on.
558 * @base: Block device that will become the new base, or %NULL to
559 * flatten the whole backing file chain onto @bs.
560 * @base_id: The file name that will be written to @bs as the new
561 * backing file if the job completes. Ignored if @base is %NULL.
562 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
563 * @on_error: The action to take upon error.
564 * @cb: Completion function for the job.
565 * @opaque: Opaque pointer value passed to @cb.
566 * @errp: Error object.
568 * Start a streaming operation on @bs. Clusters that are unallocated
569 * in @bs, but allocated in any image between @base and @bs (both
570 * exclusive) will be written to @bs. At the end of a successful
571 * streaming job, the backing file of @bs will be changed to
572 * @base_id in the written image and to @base in the live BlockDriverState.
574 void stream_start(BlockDriverState
*bs
, BlockDriverState
*base
,
575 const char *base_id
, int64_t speed
, BlockdevOnError on_error
,
576 BlockCompletionFunc
*cb
,
577 void *opaque
, Error
**errp
);
581 * @bs: Active block device.
582 * @top: Top block device to be committed.
583 * @base: Block device that will be written into, and become the new top.
584 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
585 * @on_error: The action to take upon error.
586 * @cb: Completion function for the job.
587 * @opaque: Opaque pointer value passed to @cb.
588 * @backing_file_str: String to use as the backing file in @top's overlay
589 * @errp: Error object.
592 void commit_start(BlockDriverState
*bs
, BlockDriverState
*base
,
593 BlockDriverState
*top
, int64_t speed
,
594 BlockdevOnError on_error
, BlockCompletionFunc
*cb
,
595 void *opaque
, const char *backing_file_str
, Error
**errp
);
597 * commit_active_start:
598 * @bs: Active block device to be committed.
599 * @base: Block device that will be written into, and become the new top.
600 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
601 * @on_error: The action to take upon error.
602 * @cb: Completion function for the job.
603 * @opaque: Opaque pointer value passed to @cb.
604 * @errp: Error object.
607 void commit_active_start(BlockDriverState
*bs
, BlockDriverState
*base
,
609 BlockdevOnError on_error
,
610 BlockCompletionFunc
*cb
,
611 void *opaque
, Error
**errp
);
614 * @bs: Block device to operate on.
615 * @target: Block device to write to.
616 * @replaces: Block graph node name to replace once the mirror is done. Can
617 * only be used when full mirroring is selected.
618 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
619 * @granularity: The chosen granularity for the dirty bitmap.
620 * @buf_size: The amount of data that can be in flight at one time.
621 * @mode: Whether to collapse all images in the chain to the target.
622 * @on_source_error: The action to take upon error reading from the source.
623 * @on_target_error: The action to take upon error writing to the target.
624 * @unmap: Whether to unmap target where source sectors only contain zeroes.
625 * @cb: Completion function for the job.
626 * @opaque: Opaque pointer value passed to @cb.
627 * @errp: Error object.
629 * Start a mirroring operation on @bs. Clusters that are allocated
630 * in @bs will be written to @bs until the job is cancelled or
631 * manually completed. At the end of a successful mirroring job,
632 * @bs will be switched to read from @target.
634 void mirror_start(BlockDriverState
*bs
, BlockDriverState
*target
,
635 const char *replaces
,
636 int64_t speed
, uint32_t granularity
, int64_t buf_size
,
637 MirrorSyncMode mode
, BlockdevOnError on_source_error
,
638 BlockdevOnError on_target_error
,
640 BlockCompletionFunc
*cb
,
641 void *opaque
, Error
**errp
);
645 * @bs: Block device to operate on.
646 * @target: Block device to write to.
647 * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
648 * @sync_mode: What parts of the disk image should be copied to the destination.
649 * @sync_bitmap: The dirty bitmap if sync_mode is MIRROR_SYNC_MODE_INCREMENTAL.
650 * @on_source_error: The action to take upon error reading from the source.
651 * @on_target_error: The action to take upon error writing to the target.
652 * @cb: Completion function for the job.
653 * @opaque: Opaque pointer value passed to @cb.
655 * Start a backup operation on @bs. Clusters in @bs are written to @target
656 * until the job is cancelled or manually completed.
658 void backup_start(BlockDriverState
*bs
, BlockDriverState
*target
,
659 int64_t speed
, MirrorSyncMode sync_mode
,
660 BdrvDirtyBitmap
*sync_bitmap
,
661 BlockdevOnError on_source_error
,
662 BlockdevOnError on_target_error
,
663 BlockCompletionFunc
*cb
, void *opaque
,
666 void blk_set_bs(BlockBackend
*blk
, BlockDriverState
*bs
);
668 void blk_dev_change_media_cb(BlockBackend
*blk
, bool load
);
669 bool blk_dev_has_removable_media(BlockBackend
*blk
);
670 void blk_dev_eject_request(BlockBackend
*blk
, bool force
);
671 bool blk_dev_is_tray_open(BlockBackend
*blk
);
672 bool blk_dev_is_medium_locked(BlockBackend
*blk
);
673 void blk_dev_resize_cb(BlockBackend
*blk
);
675 void bdrv_set_dirty(BlockDriverState
*bs
, int64_t cur_sector
, int nr_sectors
);
676 bool bdrv_requests_pending(BlockDriverState
*bs
);
678 #endif /* BLOCK_INT_H */