aboutsummaryrefslogtreecommitdiff
path: root/include/block/block.h
blob: 07d6d8e67e4d0dd71a159e84544ff0fd0caf9f46 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
#ifndef BLOCK_H
#define BLOCK_H

#include "block/aio.h"
#include "qemu-common.h"
#include "qemu/option.h"
#include "block/coroutine.h"
#include "block/accounting.h"
#include "qapi/qmp/qobject.h"
#include "qapi-types.h"

/* block.c */
typedef struct BlockDriver BlockDriver;
typedef struct BlockJob BlockJob;

typedef struct BlockDriverInfo {
    /* in bytes, 0 if irrelevant */
    int cluster_size;
    /* offset at which the VM state can be saved (0 if not possible) */
    int64_t vm_state_offset;
    bool is_dirty;
    /*
     * True if unallocated blocks read back as zeroes. This is equivalent
     * to the the LBPRZ flag in the SCSI logical block provisioning page.
     */
    bool unallocated_blocks_are_zero;
    /*
     * True if the driver can optimize writing zeroes by unmapping
     * sectors. This is equivalent to the BLKDISCARDZEROES ioctl in Linux
     * with the difference that in qemu a discard is allowed to silently
     * fail. Therefore we have to use bdrv_write_zeroes with the
     * BDRV_REQ_MAY_UNMAP flag for an optimized zero write with unmapping.
     * After this call the driver has to guarantee that the contents read
     * back as zero. It is additionally required that the block device is
     * opened with BDRV_O_UNMAP flag for this to work.
     */
    bool can_write_zeroes_with_unmap;
    /*
     * True if this block driver only supports compressed writes
     */
    bool needs_compressed_writes;
} BlockDriverInfo;

typedef struct BlockFragInfo {
    uint64_t allocated_clusters;
    uint64_t total_clusters;
    uint64_t fragmented_clusters;
    uint64_t compressed_clusters;
} BlockFragInfo;

/* Callbacks for block device models */
typedef struct BlockDevOps {
    /*
     * Runs when virtual media changed (monitor commands eject, change)
     * Argument load is true on load and false on eject.
     * Beware: doesn't run when a host device's physical media
     * changes.  Sure would be useful if it did.
     * Device models with removable media must implement this callback.
     */
    void (*change_media_cb)(void *opaque, bool load);
    /*
     * Runs when an eject request is issued from the monitor, the tray
     * is closed, and the medium is locked.
     * Device models that do not implement is_medium_locked will not need
     * this callback.  Device models that can lock the medium or tray might
     * want to implement the callback and unlock the tray when "force" is
     * true, even if they do not support eject requests.
     */
    void (*eject_request_cb)(void *opaque, bool force);
    /*
     * Is the virtual tray open?
     * Device models implement this only when the device has a tray.
     */
    bool (*is_tray_open)(void *opaque);
    /*
     * Is the virtual medium locked into the device?
     * Device models implement this only when device has such a lock.
     */
    bool (*is_medium_locked)(void *opaque);
    /*
     * Runs when the size changed (e.g. monitor command block_resize)
     */
    void (*resize_cb)(void *opaque);
} BlockDevOps;

typedef enum {
    BDRV_REQ_COPY_ON_READ = 0x1,
    BDRV_REQ_ZERO_WRITE   = 0x2,
    /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver
     * is allowed to optimize a write zeroes request by unmapping (discarding)
     * blocks if it is guaranteed that the result will read back as
     * zeroes. The flag is only passed to the driver if the block device is
     * opened with BDRV_O_UNMAP.
     */
    BDRV_REQ_MAY_UNMAP    = 0x4,
} BdrvRequestFlags;

#define BDRV_O_RDWR        0x0002
#define BDRV_O_SNAPSHOT    0x0008 /* open the file read only and save writes in a snapshot */
#define BDRV_O_TEMPORARY   0x0010 /* delete the file after use */
#define BDRV_O_NOCACHE     0x0020 /* do not use the host page cache */
#define BDRV_O_CACHE_WB    0x0040 /* use write-back caching */
#define BDRV_O_NATIVE_AIO  0x0080 /* use native AIO instead of the thread pool */
#define BDRV_O_NO_BACKING  0x0100 /* don't open the backing file */
#define BDRV_O_NO_FLUSH    0x0200 /* disable flushing on this disk */
#define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
#define BDRV_O_INCOMING    0x0800  /* consistency hint for incoming migration */
#define BDRV_O_CHECK       0x1000  /* open solely for consistency check */
#define BDRV_O_ALLOW_RDWR  0x2000  /* allow reopen to change from r/o to r/w */
#define BDRV_O_UNMAP       0x4000  /* execute guest UNMAP/TRIM operations */
#define BDRV_O_PROTOCOL    0x8000  /* if no block driver is explicitly given:
                                      select an appropriate protocol driver,
                                      ignoring the format layer */

#define BDRV_O_CACHE_MASK  (BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH)

#define BDRV_SECTOR_BITS   9
#define BDRV_SECTOR_SIZE   (1ULL << BDRV_SECTOR_BITS)
#define BDRV_SECTOR_MASK   ~(BDRV_SECTOR_SIZE - 1)

/* BDRV_BLOCK_DATA: data is read from bs->file or another file
 * BDRV_BLOCK_ZERO: sectors read as zero
 * BDRV_BLOCK_OFFSET_VALID: sector stored in bs->file as raw data
 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
 *                       layer (as opposed to the backing file)
 * BDRV_BLOCK_RAW: used internally to indicate that the request
 *                 was answered by the raw driver and that one
 *                 should look in bs->file directly.
 *
 * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 represent the offset in
 * bs->file where sector data can be read from as raw data.
 *
 * DATA == 0 && ZERO == 0 means that data is read from backing_hd if present.
 *
 * DATA ZERO OFFSET_VALID
 *  t    t        t       sectors read as zero, bs->file is zero at offset
 *  t    f        t       sectors read as valid from bs->file at offset
 *  f    t        t       sectors preallocated, read as zero, bs->file not
 *                        necessarily zero at offset
 *  f    f        t       sectors preallocated but read from backing_hd,
 *                        bs->file contains garbage at offset
 *  t    t        f       sectors preallocated, read as zero, unknown offset
 *  t    f        f       sectors read from unknown file or offset
 *  f    t        f       not allocated or unknown offset, read as zero
 *  f    f        f       not allocated or unknown offset, read from backing_hd
 */
#define BDRV_BLOCK_DATA         0x01
#define BDRV_BLOCK_ZERO         0x02
#define BDRV_BLOCK_OFFSET_VALID 0x04
#define BDRV_BLOCK_RAW          0x08
#define BDRV_BLOCK_ALLOCATED    0x10
#define BDRV_BLOCK_OFFSET_MASK  BDRV_SECTOR_MASK

typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue;

typedef struct BDRVReopenState {
    BlockDriverState *bs;
    int flags;
    void *opaque;
} BDRVReopenState;

/*
 * Block operation types
 */
typedef enum BlockOpType {
    BLOCK_OP_TYPE_BACKUP_SOURCE,
    BLOCK_OP_TYPE_BACKUP_TARGET,
    BLOCK_OP_TYPE_CHANGE,
    BLOCK_OP_TYPE_COMMIT,
    BLOCK_OP_TYPE_DATAPLANE,
    BLOCK_OP_TYPE_DRIVE_DEL,
    BLOCK_OP_TYPE_EJECT,
    BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
    BLOCK_OP_TYPE_INTERNAL_SNAPSHOT,
    BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE,
    BLOCK_OP_TYPE_MIRROR,
    BLOCK_OP_TYPE_RESIZE,
    BLOCK_OP_TYPE_STREAM,
    BLOCK_OP_TYPE_REPLACE,
    BLOCK_OP_TYPE_MAX,
} BlockOpType;

void bdrv_iostatus_enable(BlockDriverState *bs);
void bdrv_iostatus_reset(BlockDriverState *bs);
void bdrv_iostatus_disable(BlockDriverState *bs);
bool bdrv_iostatus_is_enabled(const BlockDriverState *bs);
void bdrv_iostatus_set_err(BlockDriverState *bs, int error);
void bdrv_info_print(Monitor *mon, const QObject *data);
void bdrv_info(Monitor *mon, QObject **ret_data);
void bdrv_stats_print(Monitor *mon, const QObject *data);
void bdrv_info_stats(Monitor *mon, QObject **ret_data);

/* disk I/O throttling */
void bdrv_io_limits_enable(BlockDriverState *bs);
void bdrv_io_limits_disable(BlockDriverState *bs);

void bdrv_init(void);
void bdrv_init_with_whitelist(void);
BlockDriver *bdrv_find_protocol(const char *filename,
                                bool allow_protocol_prefix);
BlockDriver *bdrv_find_format(const char *format_name);
BlockDriver *bdrv_find_whitelisted_format(const char *format_name,
                                          bool readonly);
int bdrv_create(BlockDriver *drv, const char* filename,
                QemuOpts *opts, Error **errp);
int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp);
BlockDriverState *bdrv_new(const char *device_name, Error **errp);
void bdrv_make_anon(BlockDriverState *bs);
void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old);
void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top);
int bdrv_parse_cache_flags(const char *mode, int *flags);
int bdrv_parse_discard_flags(const char *mode, int *flags);
int bdrv_open_image(BlockDriverState **pbs, const char *filename,
                    QDict *options, const char *bdref_key, int flags,
                    bool allow_none, Error **errp);
void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd);
int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp);
int bdrv_append_temp_snapshot(BlockDriverState *bs, int flags, Error **errp);
int bdrv_open(BlockDriverState **pbs, const char *filename,
              const char *reference, QDict *options, int flags,
              BlockDriver *drv, Error **errp);
BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
                                    BlockDriverState *bs, int flags);
int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp);
int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp);
int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
                        BlockReopenQueue *queue, Error **errp);
void bdrv_reopen_commit(BDRVReopenState *reopen_state);
void bdrv_reopen_abort(BDRVReopenState *reopen_state);
void bdrv_close(BlockDriverState *bs);
void bdrv_add_close_notifier(BlockDriverState *bs, Notifier *notify);
int bdrv_attach_dev(BlockDriverState *bs, void *dev);
void bdrv_attach_dev_nofail(BlockDriverState *bs, void *dev);
void bdrv_detach_dev(BlockDriverState *bs, void *dev);
void *bdrv_get_attached_dev(BlockDriverState *bs);
void bdrv_set_dev_ops(BlockDriverState *bs, const BlockDevOps *ops,
                      void *opaque);
void bdrv_dev_eject_request(BlockDriverState *bs, bool force);
bool bdrv_dev_has_removable_media(BlockDriverState *bs);
bool bdrv_dev_is_tray_open(BlockDriverState *bs);
bool bdrv_dev_is_medium_locked(BlockDriverState *bs);
int bdrv_read(BlockDriverState *bs, int64_t sector_num,
              uint8_t *buf, int nb_sectors);
int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
                          uint8_t *buf, int nb_sectors);
int bdrv_write(BlockDriverState *bs, int64_t sector_num,
               const uint8_t *buf, int nb_sectors);
int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num,
               int nb_sectors, BdrvRequestFlags flags);
BlockDriverAIOCB *bdrv_aio_write_zeroes(BlockDriverState *bs, int64_t sector_num,
                                        int nb_sectors, BdrvRequestFlags flags,
                                        BlockDriverCompletionFunc *cb, void *opaque);
int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags);
int bdrv_pread(BlockDriverState *bs, int64_t offset,
               void *buf, int count);
int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
                const void *buf, int count);
int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov);
int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
    const void *buf, int count);
int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num,
    int nb_sectors, QEMUIOVector *qiov);
int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
    int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,
    int nb_sectors, QEMUIOVector *qiov);
/*
 * Efficiently zero a region of the disk image.  Note that this is a regular
 * I/O request like read or write and should have a reasonable size.  This
 * function is not suitable for zeroing the entire image in a single request
 * because it may allocate memory for the entire region.
 */
int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
    int nb_sectors, BdrvRequestFlags flags);
BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
    const char *backing_file);
int bdrv_get_backing_file_depth(BlockDriverState *bs);
void bdrv_refresh_filename(BlockDriverState *bs);
int bdrv_truncate(BlockDriverState *bs, int64_t offset);
int64_t bdrv_nb_sectors(BlockDriverState *bs);
int64_t bdrv_getlength(BlockDriverState *bs);
int64_t bdrv_get_allocated_file_size(BlockDriverState *bs);
void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
void bdrv_refresh_limits(BlockDriverState *bs, Error **errp);
int bdrv_commit(BlockDriverState *bs);
int bdrv_commit_all(void);
int bdrv_change_backing_file(BlockDriverState *bs,
    const char *backing_file, const char *backing_fmt);
void bdrv_register(BlockDriver *bdrv);
int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
                           BlockDriverState *base,
                           const char *backing_file_str);
BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
                                    BlockDriverState *bs);
BlockDriverState *bdrv_find_base(BlockDriverState *bs);


typedef struct BdrvCheckResult {
    int corruptions;
    int leaks;
    int check_errors;
    int corruptions_fixed;
    int leaks_fixed;
    int64_t image_end_offset;
    BlockFragInfo bfi;
} BdrvCheckResult;

typedef enum {
    BDRV_FIX_LEAKS    = 1,
    BDRV_FIX_ERRORS   = 2,
} BdrvCheckMode;

int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);

int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts);

/* external snapshots */
bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,
                                      BlockDriverState *candidate);
bool bdrv_is_first_non_filter(BlockDriverState *candidate);

/* check if a named node can be replaced when doing drive-mirror */
BlockDriverState *check_to_replace_node(const char *node_name, Error **errp);

/* async block I/O */
typedef void BlockDriverDirtyHandler(BlockDriverState *bs, int64_t sector,
                                     int sector_num);
BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
                                 QEMUIOVector *iov, int nb_sectors,
                                 BlockDriverCompletionFunc *cb, void *opaque);
BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
                                  QEMUIOVector *iov, int nb_sectors,
                                  BlockDriverCompletionFunc *cb, void *opaque);
BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
                                 BlockDriverCompletionFunc *cb, void *opaque);
BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs,
                                   int64_t sector_num, int nb_sectors,
                                   BlockDriverCompletionFunc *cb, void *opaque);
void bdrv_aio_cancel(BlockDriverAIOCB *acb);

typedef struct BlockRequest {
    /* Fields to be filled by multiwrite caller */
    int64_t sector;
    int nb_sectors;
    int flags;
    QEMUIOVector *qiov;
    BlockDriverCompletionFunc *cb;
    void *opaque;

    /* Filled by multiwrite implementation */
    int error;
} BlockRequest;

int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs,
    int num_reqs);

/* sg packet commands */
int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf);
BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
        unsigned long int req, void *buf,
        BlockDriverCompletionFunc *cb, void *opaque);

/* Invalidate any cached metadata used by image formats */
void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
void bdrv_invalidate_cache_all(Error **errp);

void bdrv_clear_incoming_migration_all(void);

/* Ensure contents are flushed to disk.  */
int bdrv_flush(BlockDriverState *bs);
int coroutine_fn bdrv_co_flush(BlockDriverState *bs);
int bdrv_flush_all(void);
void bdrv_close_all(void);
void bdrv_drain_all(void);

int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
int bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
int bdrv_has_zero_init_1(BlockDriverState *bs);
int bdrv_has_zero_init(BlockDriverState *bs);
bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs);
bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs);
int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num,
                              int nb_sectors, int *pnum);
int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
                      int *pnum);
int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,
                            int64_t sector_num, int nb_sectors, int *pnum);

void bdrv_set_on_error(BlockDriverState *bs, BlockdevOnError on_read_error,
                       BlockdevOnError on_write_error);
BlockdevOnError bdrv_get_on_error(BlockDriverState *bs, bool is_read);
BlockErrorAction bdrv_get_error_action(BlockDriverState *bs, bool is_read, int error);
void bdrv_error_action(BlockDriverState *bs, BlockErrorAction action,
                       bool is_read, int error);
int bdrv_is_read_only(BlockDriverState *bs);
int bdrv_is_sg(BlockDriverState *bs);
int bdrv_enable_write_cache(BlockDriverState *bs);
void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce);
int bdrv_is_inserted(BlockDriverState *bs);
int bdrv_media_changed(BlockDriverState *bs);
void bdrv_lock_medium(BlockDriverState *bs, bool locked);
void bdrv_eject(BlockDriverState *bs, bool eject_flag);
const char *bdrv_get_format_name(BlockDriverState *bs);
BlockDriverState *bdrv_find(const char *name);
BlockDriverState *bdrv_find_node(const char *node_name);
BlockDeviceInfoList *bdrv_named_nodes_list(void);
BlockDriverState *bdrv_lookup_bs(const char *device,
                                 const char *node_name,
                                 Error **errp);
bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base);
BlockDriverState *bdrv_next(BlockDriverState *bs);
void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs),
                  void *opaque);
int bdrv_is_encrypted(BlockDriverState *bs);
int bdrv_key_required(BlockDriverState *bs);
int bdrv_set_key(BlockDriverState *bs, const char *key);
int bdrv_query_missing_keys(void);
void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
                         void *opaque);
const char *bdrv_get_device_name(BlockDriverState *bs);
int bdrv_get_flags(BlockDriverState *bs);
int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
                          const uint8_t *buf, int nb_sectors);
int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi);
ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs);
void bdrv_round_to_clusters(BlockDriverState *bs,
                            int64_t sector_num, int nb_sectors,
                            int64_t *cluster_sector_num,
                            int *cluster_nb_sectors);

const char *bdrv_get_encrypted_filename(BlockDriverState *bs);
void bdrv_get_backing_filename(BlockDriverState *bs,
                               char *filename, int filename_size);
void bdrv_get_full_backing_filename(BlockDriverState *bs,
                                    char *dest, size_t sz);
int bdrv_is_snapshot(BlockDriverState *bs);

int path_is_absolute(const char *path);
void path_combine(char *dest, int dest_size,
                  const char *base_path,
                  const char *filename);

int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
                      int64_t pos, int size);

int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
                      int64_t pos, int size);

void bdrv_img_create(const char *filename, const char *fmt,
                     const char *base_filename, const char *base_fmt,
                     char *options, uint64_t img_size, int flags,
                     Error **errp, bool quiet);

/* Returns the alignment in bytes that is required so that no bounce buffer
 * is required throughout the stack */
size_t bdrv_opt_mem_align(BlockDriverState *bs);
void bdrv_set_guest_block_size(BlockDriverState *bs, int align);
void *qemu_blockalign(BlockDriverState *bs, size_t size);
void *qemu_try_blockalign(BlockDriverState *bs, size_t size);
bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);

struct HBitmapIter;
typedef struct BdrvDirtyBitmap BdrvDirtyBitmap;
BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, int granularity,
                                          Error **errp);
void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors);
void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors);
void bdrv_dirty_iter_init(BlockDriverState *bs,
                          BdrvDirtyBitmap *bitmap, struct HBitmapIter *hbi);
int64_t bdrv_get_dirty_count(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);

void bdrv_enable_copy_on_read(BlockDriverState *bs);
void bdrv_disable_copy_on_read(BlockDriverState *bs);

void bdrv_ref(BlockDriverState *bs);
void bdrv_unref(BlockDriverState *bs);

bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason);
void bdrv_op_block_all(BlockDriverState *bs, Error *reason);
void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason);
bool bdrv_op_blocker_is_empty(BlockDriverState *bs);

typedef enum {
    BLKDBG_L1_UPDATE,

    BLKDBG_L1_GROW_ALLOC_TABLE,
    BLKDBG_L1_GROW_WRITE_TABLE,
    BLKDBG_L1_GROW_ACTIVATE_TABLE,

    BLKDBG_L2_LOAD,
    BLKDBG_L2_UPDATE,
    BLKDBG_L2_UPDATE_COMPRESSED,
    BLKDBG_L2_ALLOC_COW_READ,
    BLKDBG_L2_ALLOC_WRITE,

    BLKDBG_READ_AIO,
    BLKDBG_READ_BACKING_AIO,
    BLKDBG_READ_COMPRESSED,

    BLKDBG_WRITE_AIO,
    BLKDBG_WRITE_COMPRESSED,

    BLKDBG_VMSTATE_LOAD,
    BLKDBG_VMSTATE_SAVE,

    BLKDBG_COW_READ,
    BLKDBG_COW_WRITE,

    BLKDBG_REFTABLE_LOAD,
    BLKDBG_REFTABLE_GROW,
    BLKDBG_REFTABLE_UPDATE,

    BLKDBG_REFBLOCK_LOAD,
    BLKDBG_REFBLOCK_UPDATE,
    BLKDBG_REFBLOCK_UPDATE_PART,
    BLKDBG_REFBLOCK_ALLOC,
    BLKDBG_REFBLOCK_ALLOC_HOOKUP,
    BLKDBG_REFBLOCK_ALLOC_WRITE,
    BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS,
    BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE,
    BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE,

    BLKDBG_CLUSTER_ALLOC,
    BLKDBG_CLUSTER_ALLOC_BYTES,
    BLKDBG_CLUSTER_FREE,

    BLKDBG_FLUSH_TO_OS,
    BLKDBG_FLUSH_TO_DISK,

    BLKDBG_PWRITEV_RMW_HEAD,
    BLKDBG_PWRITEV_RMW_AFTER_HEAD,
    BLKDBG_PWRITEV_RMW_TAIL,
    BLKDBG_PWRITEV_RMW_AFTER_TAIL,
    BLKDBG_PWRITEV,
    BLKDBG_PWRITEV_ZERO,
    BLKDBG_PWRITEV_DONE,

    BLKDBG_EVENT_MAX,
} BlkDebugEvent;

#define BLKDBG_EVENT(bs, evt) bdrv_debug_event(bs, evt)
void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event);

int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
                           const char *tag);
int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag);
int bdrv_debug_resume(BlockDriverState *bs, const char *tag);
bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag);

/**
 * bdrv_get_aio_context:
 *
 * Returns: the currently bound #AioContext
 */
AioContext *bdrv_get_aio_context(BlockDriverState *bs);

/**
 * bdrv_set_aio_context:
 *
 * Changes the #AioContext used for fd handlers, timers, and BHs by this
 * BlockDriverState and all its children.
 *
 * This function must be called from the old #AioContext or with a lock held so
 * the old #AioContext is not executing.
 */
void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context);

void bdrv_io_plug(BlockDriverState *bs);
void bdrv_io_unplug(BlockDriverState *bs);
void bdrv_flush_io_queue(BlockDriverState *bs);

BlockAcctStats *bdrv_get_stats(BlockDriverState *bs);

#endif