xref: /openbmc/qemu/include/block/block_int.h (revision 81b07353c5e7ae9ae9360c357b7b4732b1cb03b4)
1 /*
2  * QEMU System Emulator block driver
3  *
4  * Copyright (c) 2003 Fabrice Bellard
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #ifndef BLOCK_INT_H
25 #define BLOCK_INT_H
26 
27 #include "block/accounting.h"
28 #include "block/block.h"
29 #include "qemu/option.h"
30 #include "qemu/queue.h"
31 #include "block/coroutine.h"
32 #include "qemu/timer.h"
33 #include "qapi-types.h"
34 #include "qapi/qmp/qerror.h"
35 #include "monitor/monitor.h"
36 #include "qemu/hbitmap.h"
37 #include "block/snapshot.h"
38 #include "qemu/main-loop.h"
39 #include "qemu/throttle.h"
40 
41 #define BLOCK_FLAG_ENCRYPT          1
42 #define BLOCK_FLAG_COMPAT6          4
43 #define BLOCK_FLAG_LAZY_REFCOUNTS   8
44 
45 #define BLOCK_OPT_SIZE              "size"
46 #define BLOCK_OPT_ENCRYPT           "encryption"
47 #define BLOCK_OPT_COMPAT6           "compat6"
48 #define BLOCK_OPT_BACKING_FILE      "backing_file"
49 #define BLOCK_OPT_BACKING_FMT       "backing_fmt"
50 #define BLOCK_OPT_CLUSTER_SIZE      "cluster_size"
51 #define BLOCK_OPT_TABLE_SIZE        "table_size"
52 #define BLOCK_OPT_PREALLOC          "preallocation"
53 #define BLOCK_OPT_SUBFMT            "subformat"
54 #define BLOCK_OPT_COMPAT_LEVEL      "compat"
55 #define BLOCK_OPT_LAZY_REFCOUNTS    "lazy_refcounts"
56 #define BLOCK_OPT_ADAPTER_TYPE      "adapter_type"
57 #define BLOCK_OPT_REDUNDANCY        "redundancy"
58 #define BLOCK_OPT_NOCOW             "nocow"
59 
60 #define BLOCK_PROBE_BUF_SIZE        512
61 
62 typedef struct BdrvTrackedRequest {
63     BlockDriverState *bs;
64     int64_t offset;
65     unsigned int bytes;
66     bool is_write;
67 
68     bool serialising;
69     int64_t overlap_offset;
70     unsigned int overlap_bytes;
71 
72     QLIST_ENTRY(BdrvTrackedRequest) list;
73     Coroutine *co; /* owner, used for deadlock detection */
74     CoQueue wait_queue; /* coroutines blocked on this request */
75 
76     struct BdrvTrackedRequest *waiting_for;
77 } BdrvTrackedRequest;
78 
79 struct BlockDriver {
80     const char *format_name;
81     int instance_size;
82 
83     /* set to true if the BlockDriver is a block filter */
84     bool is_filter;
85     /* for snapshots block filter like Quorum can implement the
86      * following recursive callback.
87      * It's purpose is to recurse on the filter children while calling
88      * bdrv_recurse_is_first_non_filter on them.
89      * For a sample implementation look in the future Quorum block filter.
90      */
91     bool (*bdrv_recurse_is_first_non_filter)(BlockDriverState *bs,
92                                              BlockDriverState *candidate);
93 
94     int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
95     int (*bdrv_probe_device)(const char *filename);
96 
97     /* Any driver implementing this callback is expected to be able to handle
98      * NULL file names in its .bdrv_open() implementation */
99     void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp);
100     /* Drivers not implementing bdrv_parse_filename nor bdrv_open should have
101      * this field set to true, except ones that are defined only by their
102      * child's bs.
103      * An example of the last type will be the quorum block driver.
104      */
105     bool bdrv_needs_filename;
106 
107     /* Set if a driver can support backing files */
108     bool supports_backing;
109 
110     /* For handling image reopen for split or non-split files */
111     int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state,
112                                BlockReopenQueue *queue, Error **errp);
113     void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state);
114     void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state);
115 
116     int (*bdrv_open)(BlockDriverState *bs, QDict *options, int flags,
117                      Error **errp);
118     int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags,
119                           Error **errp);
120     int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
121                      uint8_t *buf, int nb_sectors);
122     int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,
123                       const uint8_t *buf, int nb_sectors);
124     void (*bdrv_close)(BlockDriverState *bs);
125     void (*bdrv_rebind)(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);
129 
130     void (*bdrv_refresh_filename)(BlockDriverState *bs);
131 
132     /* aio */
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);
144 
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);
149     /*
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
153      * instead.
154      */
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);
161 
162     /*
163      * Invalidate any cached meta-data.
164      */
165     void (*bdrv_invalidate_cache)(BlockDriverState *bs, Error **errp);
166 
167     /*
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()).
170      */
171     int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs);
172 
173     /*
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
176      * process.
177      */
178     int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs);
179 
180     const char *protocol_name;
181     int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
182 
183     int64_t (*bdrv_getlength)(BlockDriverState *bs);
184     bool has_variable_length;
185     int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs);
186 
187     int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
188                                  const uint8_t *buf, int nb_sectors);
189 
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,
196                                 const char *name,
197                                 Error **errp);
198     int (*bdrv_snapshot_list)(BlockDriverState *bs,
199                               QEMUSnapshotInfo **psn_info);
200     int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
201                                   const char *snapshot_id,
202                                   const char *name,
203                                   Error **errp);
204     int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
205     ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs);
206 
207     int (*bdrv_save_vmstate)(BlockDriverState *bs, QEMUIOVector *qiov,
208                              int64_t pos);
209     int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,
210                              int64_t pos, int size);
211 
212     int (*bdrv_change_backing_file)(BlockDriverState *bs,
213         const char *backing_file, const char *backing_fmt);
214 
215     /* removable device specific */
216     int (*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);
220 
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);
226 
227     /* List of options for creating images, terminated by name == NULL */
228     QemuOptsList *create_opts;
229 
230     /*
231      * Returns 0 for completed check, -errno for internal errors.
232      * The check results are stored in result.
233      */
234     int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result,
235         BdrvCheckMode fix);
236 
237     int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts,
238                               BlockDriverAmendStatusCB *status_cb);
239 
240     void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
241 
242     /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */
243     int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event,
244         const char *tag);
245     int (*bdrv_debug_remove_breakpoint)(BlockDriverState *bs,
246         const char *tag);
247     int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag);
248     bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag);
249 
250     void (*bdrv_refresh_limits)(BlockDriverState *bs, Error **errp);
251 
252     /*
253      * Returns 1 if newly created images are guaranteed to contain only
254      * zeros, 0 otherwise.
255      */
256     int (*bdrv_has_zero_init)(BlockDriverState *bs);
257 
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.
261      */
262     void (*bdrv_detach_aio_context)(BlockDriverState *bs);
263 
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.
267      */
268     void (*bdrv_attach_aio_context)(BlockDriverState *bs,
269                                     AioContext *new_context);
270 
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);
275 
276     QLIST_ENTRY(BlockDriver) list;
277 };
278 
279 typedef struct BlockLimits {
280     /* maximum number of sectors that can be discarded at once */
281     int max_discard;
282 
283     /* optimal alignment for discard requests in sectors */
284     int64_t discard_alignment;
285 
286     /* maximum number of sectors that can zeroized at once */
287     int max_write_zeroes;
288 
289     /* optimal alignment for write zeroes requests in sectors */
290     int64_t write_zeroes_alignment;
291 
292     /* optimal transfer length in sectors */
293     int opt_transfer_length;
294 
295     /* maximal transfer length in sectors */
296     int max_transfer_length;
297 
298     /* memory alignment so that no bounce buffer is needed */
299     size_t opt_mem_alignment;
300 } BlockLimits;
301 
302 typedef struct BdrvOpBlocker BdrvOpBlocker;
303 
304 typedef struct BdrvAioNotifier {
305     void (*attached_aio_context)(AioContext *new_context, void *opaque);
306     void (*detach_aio_context)(void *opaque);
307 
308     void *opaque;
309 
310     QLIST_ENTRY(BdrvAioNotifier) list;
311 } BdrvAioNotifier;
312 
313 /*
314  * Note: the function bdrv_append() copies and swaps contents of
315  * BlockDriverStates, so if you add new fields to this struct, please
316  * inspect bdrv_append() to determine if the new fields need to be
317  * copied as well.
318  */
319 struct BlockDriverState {
320     int64_t total_sectors; /* if we are reading a disk image, give its
321                               size in sectors */
322     int read_only; /* if true, the media is read only */
323     int open_flags; /* flags used to open the file, re-used for re-open */
324     int encrypted; /* if true, the media is encrypted */
325     int valid_key; /* if true, a valid encryption key has been set */
326     int sg;        /* if true, the device is a /dev/sg* */
327     int copy_on_read; /* if true, copy read backing sectors into image
328                          note this is a reference count */
329     bool probed;
330 
331     BlockDriver *drv; /* NULL means no media */
332     void *opaque;
333 
334     BlockBackend *blk;          /* owning backend, if any */
335 
336     AioContext *aio_context; /* event loop used for fd handlers, timers, etc */
337     /* long-running tasks intended to always use the same AioContext as this
338      * BDS may register themselves in this list to be notified of changes
339      * regarding this BDS's context */
340     QLIST_HEAD(, BdrvAioNotifier) aio_notifiers;
341 
342     char filename[PATH_MAX];
343     char backing_file[PATH_MAX]; /* if non zero, the image is a diff of
344                                     this file image */
345     char backing_format[16]; /* if non-zero and backing_file exists */
346 
347     QDict *full_open_options;
348     char exact_filename[PATH_MAX];
349 
350     BlockDriverState *backing_hd;
351     BlockDriverState *file;
352 
353     NotifierList close_notifiers;
354 
355     /* Callback before write request is processed */
356     NotifierWithReturnList before_write_notifiers;
357 
358     /* number of in-flight serialising requests */
359     unsigned int serialising_in_flight;
360 
361     /* I/O throttling */
362     ThrottleState throttle_state;
363     CoQueue      throttled_reqs[2];
364     bool         io_limits_enabled;
365 
366     /* I/O stats (display with "info blockstats"). */
367     BlockAcctStats stats;
368 
369     /* I/O Limits */
370     BlockLimits bl;
371 
372     /* Whether produces zeros when read beyond eof */
373     bool zero_beyond_eof;
374 
375     /* Alignment requirement for offset/length of I/O requests */
376     unsigned int request_alignment;
377 
378     /* the block size for which the guest device expects atomicity */
379     int guest_block_size;
380 
381     /* do we need to tell the quest if we have a volatile write cache? */
382     int enable_write_cache;
383 
384     /* NOTE: the following infos are only hints for real hardware
385        drivers. They are not used by the block driver */
386     BlockdevOnError on_read_error, on_write_error;
387     bool iostatus_enabled;
388     BlockDeviceIoStatus iostatus;
389 
390     /* the following member gives a name to every node on the bs graph. */
391     char node_name[32];
392     /* element of the list of named nodes building the graph */
393     QTAILQ_ENTRY(BlockDriverState) node_list;
394     /* element of the list of "drives" the guest sees */
395     QTAILQ_ENTRY(BlockDriverState) device_list;
396     QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps;
397     int refcnt;
398 
399     QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
400 
401     /* operation blockers */
402     QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX];
403 
404     /* long-running background operation */
405     BlockJob *job;
406 
407     QDict *options;
408     BlockdevDetectZeroesOptions detect_zeroes;
409 
410     /* The error object in use for blocking operations on backing_hd */
411     Error *backing_blocker;
412 
413     /* threshold limit for writes, in bytes. "High water mark". */
414     uint64_t write_threshold_offset;
415     NotifierWithReturn write_threshold_notifier;
416 };
417 
418 
419 /* Essential block drivers which must always be statically linked into qemu, and
420  * which therefore can be accessed without using bdrv_find_format() */
421 extern BlockDriver bdrv_file;
422 extern BlockDriver bdrv_raw;
423 extern BlockDriver bdrv_qcow2;
424 
425 
426 int get_tmp_filename(char *filename, int size);
427 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
428                             const char *filename);
429 
430 void bdrv_set_io_limits(BlockDriverState *bs,
431                         ThrottleConfig *cfg);
432 
433 
434 /**
435  * bdrv_add_before_write_notifier:
436  *
437  * Register a callback that is invoked before write requests are processed but
438  * after any throttling or waiting for overlapping requests.
439  */
440 void bdrv_add_before_write_notifier(BlockDriverState *bs,
441                                     NotifierWithReturn *notifier);
442 
443 /**
444  * bdrv_detach_aio_context:
445  *
446  * May be called from .bdrv_detach_aio_context() to detach children from the
447  * current #AioContext.  This is only needed by block drivers that manage their
448  * own children.  Both ->file and ->backing_hd are automatically handled and
449  * block drivers should not call this function on them explicitly.
450  */
451 void bdrv_detach_aio_context(BlockDriverState *bs);
452 
453 /**
454  * bdrv_attach_aio_context:
455  *
456  * May be called from .bdrv_attach_aio_context() to attach children to the new
457  * #AioContext.  This is only needed by block drivers that manage their own
458  * children.  Both ->file and ->backing_hd are automatically handled and block
459  * drivers should not call this function on them explicitly.
460  */
461 void bdrv_attach_aio_context(BlockDriverState *bs,
462                              AioContext *new_context);
463 
464 /**
465  * bdrv_add_aio_context_notifier:
466  *
467  * If a long-running job intends to be always run in the same AioContext as a
468  * certain BDS, it may use this function to be notified of changes regarding the
469  * association of the BDS to an AioContext.
470  *
471  * attached_aio_context() is called after the target BDS has been attached to a
472  * new AioContext; detach_aio_context() is called before the target BDS is being
473  * detached from its old AioContext.
474  */
475 void bdrv_add_aio_context_notifier(BlockDriverState *bs,
476         void (*attached_aio_context)(AioContext *new_context, void *opaque),
477         void (*detach_aio_context)(void *opaque), void *opaque);
478 
479 /**
480  * bdrv_remove_aio_context_notifier:
481  *
482  * Unsubscribe of change notifications regarding the BDS's AioContext. The
483  * parameters given here have to be the same as those given to
484  * bdrv_add_aio_context_notifier().
485  */
486 void bdrv_remove_aio_context_notifier(BlockDriverState *bs,
487                                       void (*aio_context_attached)(AioContext *,
488                                                                    void *),
489                                       void (*aio_context_detached)(void *),
490                                       void *opaque);
491 
492 #ifdef _WIN32
493 int is_windows_drive(const char *filename);
494 #endif
495 
496 /**
497  * stream_start:
498  * @bs: Block device to operate on.
499  * @base: Block device that will become the new base, or %NULL to
500  * flatten the whole backing file chain onto @bs.
501  * @base_id: The file name that will be written to @bs as the new
502  * backing file if the job completes.  Ignored if @base is %NULL.
503  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
504  * @on_error: The action to take upon error.
505  * @cb: Completion function for the job.
506  * @opaque: Opaque pointer value passed to @cb.
507  * @errp: Error object.
508  *
509  * Start a streaming operation on @bs.  Clusters that are unallocated
510  * in @bs, but allocated in any image between @base and @bs (both
511  * exclusive) will be written to @bs.  At the end of a successful
512  * streaming job, the backing file of @bs will be changed to
513  * @base_id in the written image and to @base in the live BlockDriverState.
514  */
515 void stream_start(BlockDriverState *bs, BlockDriverState *base,
516                   const char *base_id, int64_t speed, BlockdevOnError on_error,
517                   BlockCompletionFunc *cb,
518                   void *opaque, Error **errp);
519 
520 /**
521  * commit_start:
522  * @bs: Active block device.
523  * @top: Top block device to be committed.
524  * @base: Block device that will be written into, and become the new top.
525  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
526  * @on_error: The action to take upon error.
527  * @cb: Completion function for the job.
528  * @opaque: Opaque pointer value passed to @cb.
529  * @backing_file_str: String to use as the backing file in @top's overlay
530  * @errp: Error object.
531  *
532  */
533 void commit_start(BlockDriverState *bs, BlockDriverState *base,
534                  BlockDriverState *top, int64_t speed,
535                  BlockdevOnError on_error, BlockCompletionFunc *cb,
536                  void *opaque, const char *backing_file_str, Error **errp);
537 /**
538  * commit_active_start:
539  * @bs: Active block device to be committed.
540  * @base: Block device that will be written into, and become the new top.
541  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
542  * @on_error: The action to take upon error.
543  * @cb: Completion function for the job.
544  * @opaque: Opaque pointer value passed to @cb.
545  * @errp: Error object.
546  *
547  */
548 void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
549                          int64_t speed,
550                          BlockdevOnError on_error,
551                          BlockCompletionFunc *cb,
552                          void *opaque, Error **errp);
553 /*
554  * mirror_start:
555  * @bs: Block device to operate on.
556  * @target: Block device to write to.
557  * @replaces: Block graph node name to replace once the mirror is done. Can
558  *            only be used when full mirroring is selected.
559  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
560  * @granularity: The chosen granularity for the dirty bitmap.
561  * @buf_size: The amount of data that can be in flight at one time.
562  * @mode: Whether to collapse all images in the chain to the target.
563  * @on_source_error: The action to take upon error reading from the source.
564  * @on_target_error: The action to take upon error writing to the target.
565  * @cb: Completion function for the job.
566  * @opaque: Opaque pointer value passed to @cb.
567  * @errp: Error object.
568  *
569  * Start a mirroring operation on @bs.  Clusters that are allocated
570  * in @bs will be written to @bs until the job is cancelled or
571  * manually completed.  At the end of a successful mirroring job,
572  * @bs will be switched to read from @target.
573  */
574 void mirror_start(BlockDriverState *bs, BlockDriverState *target,
575                   const char *replaces,
576                   int64_t speed, int64_t granularity, int64_t buf_size,
577                   MirrorSyncMode mode, BlockdevOnError on_source_error,
578                   BlockdevOnError on_target_error,
579                   BlockCompletionFunc *cb,
580                   void *opaque, Error **errp);
581 
582 /*
583  * backup_start:
584  * @bs: Block device to operate on.
585  * @target: Block device to write to.
586  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
587  * @sync_mode: What parts of the disk image should be copied to the destination.
588  * @on_source_error: The action to take upon error reading from the source.
589  * @on_target_error: The action to take upon error writing to the target.
590  * @cb: Completion function for the job.
591  * @opaque: Opaque pointer value passed to @cb.
592  *
593  * Start a backup operation on @bs.  Clusters in @bs are written to @target
594  * until the job is cancelled or manually completed.
595  */
596 void backup_start(BlockDriverState *bs, BlockDriverState *target,
597                   int64_t speed, MirrorSyncMode sync_mode,
598                   BlockdevOnError on_source_error,
599                   BlockdevOnError on_target_error,
600                   BlockCompletionFunc *cb, void *opaque,
601                   Error **errp);
602 
603 void blk_dev_change_media_cb(BlockBackend *blk, bool load);
604 bool blk_dev_has_removable_media(BlockBackend *blk);
605 void blk_dev_eject_request(BlockBackend *blk, bool force);
606 bool blk_dev_is_tray_open(BlockBackend *blk);
607 bool blk_dev_is_medium_locked(BlockBackend *blk);
608 void blk_dev_resize_cb(BlockBackend *blk);
609 
610 #endif /* BLOCK_INT_H */
611