vhost-user-blk: Explicit we ignore few QEMUChrEvent in IOEventHandler
[qemu/ar7.git] / include / block / block.h
blobe9dcfef7fa463e7655b4ec4a0d7c1b37b6dc45f7
1 #ifndef BLOCK_H
2 #define BLOCK_H
4 #include "block/aio.h"
5 #include "block/aio-wait.h"
6 #include "qemu/iov.h"
7 #include "qemu/coroutine.h"
8 #include "block/accounting.h"
9 #include "block/dirty-bitmap.h"
10 #include "block/blockjob.h"
11 #include "qemu/hbitmap.h"
13 /* block.c */
14 typedef struct BlockDriver BlockDriver;
15 typedef struct BdrvChild BdrvChild;
16 typedef struct BdrvChildRole BdrvChildRole;
18 typedef struct BlockDriverInfo {
19 /* in bytes, 0 if irrelevant */
20 int cluster_size;
21 /* offset at which the VM state can be saved (0 if not possible) */
22 int64_t vm_state_offset;
23 bool is_dirty;
25 * True if unallocated blocks read back as zeroes. This is equivalent
26 * to the LBPRZ flag in the SCSI logical block provisioning page.
28 bool unallocated_blocks_are_zero;
30 * True if this block driver only supports compressed writes
32 bool needs_compressed_writes;
33 } BlockDriverInfo;
35 typedef struct BlockFragInfo {
36 uint64_t allocated_clusters;
37 uint64_t total_clusters;
38 uint64_t fragmented_clusters;
39 uint64_t compressed_clusters;
40 } BlockFragInfo;
42 typedef enum {
43 BDRV_REQ_COPY_ON_READ = 0x1,
44 BDRV_REQ_ZERO_WRITE = 0x2,
47 * The BDRV_REQ_MAY_UNMAP flag is used in write_zeroes requests to indicate
48 * that the block driver should unmap (discard) blocks if it is guaranteed
49 * that the result will read back as zeroes. The flag is only passed to the
50 * driver if the block device is opened with BDRV_O_UNMAP.
52 BDRV_REQ_MAY_UNMAP = 0x4,
55 * The BDRV_REQ_NO_SERIALISING flag is only valid for reads and means that
56 * we don't want wait_serialising_requests() during the read operation.
58 * This flag is used for backup copy-on-write operations, when we need to
59 * read old data before write (write notifier triggered). It is okay since
60 * we already waited for other serializing requests in the initiating write
61 * (see bdrv_aligned_pwritev), and it is necessary if the initiating write
62 * is already serializing (without the flag, the read would deadlock
63 * waiting for the serialising write to complete).
65 BDRV_REQ_NO_SERIALISING = 0x8,
66 BDRV_REQ_FUA = 0x10,
67 BDRV_REQ_WRITE_COMPRESSED = 0x20,
69 /* Signifies that this write request will not change the visible disk
70 * content. */
71 BDRV_REQ_WRITE_UNCHANGED = 0x40,
74 * BDRV_REQ_SERIALISING forces request serialisation for writes.
75 * It is used to ensure that writes to the backing file of a backup process
76 * target cannot race with a read of the backup target that defers to the
77 * backing file.
79 * Note, that BDRV_REQ_SERIALISING is _not_ opposite in meaning to
80 * BDRV_REQ_NO_SERIALISING. A more descriptive name for the latter might be
81 * _DO_NOT_WAIT_FOR_SERIALISING, except that is too long.
83 BDRV_REQ_SERIALISING = 0x80,
85 /* Execute the request only if the operation can be offloaded or otherwise
86 * be executed efficiently, but return an error instead of using a slow
87 * fallback. */
88 BDRV_REQ_NO_FALLBACK = 0x100,
91 * BDRV_REQ_PREFETCH may be used only together with BDRV_REQ_COPY_ON_READ
92 * on read request and means that caller doesn't really need data to be
93 * written to qiov parameter which may be NULL.
95 BDRV_REQ_PREFETCH = 0x200,
96 /* Mask of valid flags */
97 BDRV_REQ_MASK = 0x3ff,
98 } BdrvRequestFlags;
100 typedef struct BlockSizes {
101 uint32_t phys;
102 uint32_t log;
103 } BlockSizes;
105 typedef struct HDGeometry {
106 uint32_t heads;
107 uint32_t sectors;
108 uint32_t cylinders;
109 } HDGeometry;
111 #define BDRV_O_RDWR 0x0002
112 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */
113 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */
114 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */
115 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */
116 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */
117 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */
118 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */
119 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
120 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */
121 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */
122 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */
123 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */
124 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given:
125 select an appropriate protocol driver,
126 ignoring the format layer */
127 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */
128 #define BDRV_O_AUTO_RDONLY 0x20000 /* degrade to read-only if opening read-write fails */
130 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH)
133 /* Option names of options parsed by the block layer */
135 #define BDRV_OPT_CACHE_WB "cache.writeback"
136 #define BDRV_OPT_CACHE_DIRECT "cache.direct"
137 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush"
138 #define BDRV_OPT_READ_ONLY "read-only"
139 #define BDRV_OPT_AUTO_READ_ONLY "auto-read-only"
140 #define BDRV_OPT_DISCARD "discard"
141 #define BDRV_OPT_FORCE_SHARE "force-share"
144 #define BDRV_SECTOR_BITS 9
145 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS)
147 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \
148 INT_MAX >> BDRV_SECTOR_BITS)
149 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS)
152 * Allocation status flags for bdrv_block_status() and friends.
154 * Public flags:
155 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer
156 * BDRV_BLOCK_ZERO: offset reads as zero
157 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data
158 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
159 * layer rather than any backing, set by block layer
160 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this
161 * layer, set by block layer
163 * Internal flags:
164 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request
165 * that the block layer recompute the answer from the returned
166 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID.
167 * BDRV_BLOCK_RECURSE: request that the block layer will recursively search for
168 * zeroes in file child of current block node inside
169 * returned region. Only valid together with both
170 * BDRV_BLOCK_DATA and BDRV_BLOCK_OFFSET_VALID. Should not
171 * appear with BDRV_BLOCK_ZERO.
173 * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the
174 * host offset within the returned BDS that is allocated for the
175 * corresponding raw guest data. However, whether that offset
176 * actually contains data also depends on BDRV_BLOCK_DATA, as follows:
178 * DATA ZERO OFFSET_VALID
179 * t t t sectors read as zero, returned file is zero at offset
180 * t f t sectors read as valid from file at offset
181 * f t t sectors preallocated, read as zero, returned file not
182 * necessarily zero at offset
183 * f f t sectors preallocated but read from backing_hd,
184 * returned file contains garbage at offset
185 * t t f sectors preallocated, read as zero, unknown offset
186 * t f f sectors read from unknown file or offset
187 * f t f not allocated or unknown offset, read as zero
188 * f f f not allocated or unknown offset, read from backing_hd
190 #define BDRV_BLOCK_DATA 0x01
191 #define BDRV_BLOCK_ZERO 0x02
192 #define BDRV_BLOCK_OFFSET_VALID 0x04
193 #define BDRV_BLOCK_RAW 0x08
194 #define BDRV_BLOCK_ALLOCATED 0x10
195 #define BDRV_BLOCK_EOF 0x20
196 #define BDRV_BLOCK_RECURSE 0x40
198 typedef QTAILQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue;
200 typedef struct BDRVReopenState {
201 BlockDriverState *bs;
202 int flags;
203 BlockdevDetectZeroesOptions detect_zeroes;
204 bool backing_missing;
205 bool replace_backing_bs; /* new_backing_bs is ignored if this is false */
206 BlockDriverState *new_backing_bs; /* If NULL then detach the current bs */
207 uint64_t perm, shared_perm;
208 QDict *options;
209 QDict *explicit_options;
210 void *opaque;
211 } BDRVReopenState;
214 * Block operation types
216 typedef enum BlockOpType {
217 BLOCK_OP_TYPE_BACKUP_SOURCE,
218 BLOCK_OP_TYPE_BACKUP_TARGET,
219 BLOCK_OP_TYPE_CHANGE,
220 BLOCK_OP_TYPE_COMMIT_SOURCE,
221 BLOCK_OP_TYPE_COMMIT_TARGET,
222 BLOCK_OP_TYPE_DATAPLANE,
223 BLOCK_OP_TYPE_DRIVE_DEL,
224 BLOCK_OP_TYPE_EJECT,
225 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
226 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT,
227 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE,
228 BLOCK_OP_TYPE_MIRROR_SOURCE,
229 BLOCK_OP_TYPE_MIRROR_TARGET,
230 BLOCK_OP_TYPE_RESIZE,
231 BLOCK_OP_TYPE_STREAM,
232 BLOCK_OP_TYPE_REPLACE,
233 BLOCK_OP_TYPE_MAX,
234 } BlockOpType;
236 /* Block node permission constants */
237 enum {
239 * A user that has the "permission" of consistent reads is guaranteed that
240 * their view of the contents of the block device is complete and
241 * self-consistent, representing the contents of a disk at a specific
242 * point.
244 * For most block devices (including their backing files) this is true, but
245 * the property cannot be maintained in a few situations like for
246 * intermediate nodes of a commit block job.
248 BLK_PERM_CONSISTENT_READ = 0x01,
250 /** This permission is required to change the visible disk contents. */
251 BLK_PERM_WRITE = 0x02,
254 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and
255 * required for writes to the block node when the caller promises that
256 * the visible disk content doesn't change.
258 * As the BLK_PERM_WRITE permission is strictly stronger, either is
259 * sufficient to perform an unchanging write.
261 BLK_PERM_WRITE_UNCHANGED = 0x04,
263 /** This permission is required to change the size of a block node. */
264 BLK_PERM_RESIZE = 0x08,
267 * This permission is required to change the node that this BdrvChild
268 * points to.
270 BLK_PERM_GRAPH_MOD = 0x10,
272 BLK_PERM_ALL = 0x1f,
274 DEFAULT_PERM_PASSTHROUGH = BLK_PERM_CONSISTENT_READ
275 | BLK_PERM_WRITE
276 | BLK_PERM_WRITE_UNCHANGED
277 | BLK_PERM_RESIZE,
279 DEFAULT_PERM_UNCHANGED = BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH,
282 char *bdrv_perm_names(uint64_t perm);
283 uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm);
285 /* disk I/O throttling */
286 void bdrv_init(void);
287 void bdrv_init_with_whitelist(void);
288 bool bdrv_uses_whitelist(void);
289 int bdrv_is_whitelisted(BlockDriver *drv, bool read_only);
290 BlockDriver *bdrv_find_protocol(const char *filename,
291 bool allow_protocol_prefix,
292 Error **errp);
293 BlockDriver *bdrv_find_format(const char *format_name);
294 int bdrv_create(BlockDriver *drv, const char* filename,
295 QemuOpts *opts, Error **errp);
296 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp);
297 BlockDriverState *bdrv_new(void);
298 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top,
299 Error **errp);
300 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to,
301 Error **errp);
303 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough);
304 int bdrv_parse_discard_flags(const char *mode, int *flags);
305 BdrvChild *bdrv_open_child(const char *filename,
306 QDict *options, const char *bdref_key,
307 BlockDriverState* parent,
308 const BdrvChildRole *child_role,
309 bool allow_none, Error **errp);
310 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp);
311 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd,
312 Error **errp);
313 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options,
314 const char *bdref_key, Error **errp);
315 BlockDriverState *bdrv_open(const char *filename, const char *reference,
316 QDict *options, int flags, Error **errp);
317 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name,
318 int flags, Error **errp);
319 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
320 BlockDriverState *bs, QDict *options,
321 bool keep_old_opts);
322 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp);
323 int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only,
324 Error **errp);
325 int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
326 BlockReopenQueue *queue, Error **errp);
327 void bdrv_reopen_commit(BDRVReopenState *reopen_state);
328 void bdrv_reopen_abort(BDRVReopenState *reopen_state);
329 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
330 int bytes, BdrvRequestFlags flags);
331 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags);
332 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes);
333 int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov);
334 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes);
335 int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov);
336 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset,
337 const void *buf, int count);
339 * Efficiently zero a region of the disk image. Note that this is a regular
340 * I/O request like read or write and should have a reasonable size. This
341 * function is not suitable for zeroing the entire image in a single request
342 * because it may allocate memory for the entire region.
344 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset,
345 int bytes, BdrvRequestFlags flags);
346 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
347 const char *backing_file);
348 void bdrv_refresh_filename(BlockDriverState *bs);
350 int coroutine_fn bdrv_co_truncate(BdrvChild *child, int64_t offset, bool exact,
351 PreallocMode prealloc, Error **errp);
352 int bdrv_truncate(BdrvChild *child, int64_t offset, bool exact,
353 PreallocMode prealloc, Error **errp);
355 int64_t bdrv_nb_sectors(BlockDriverState *bs);
356 int64_t bdrv_getlength(BlockDriverState *bs);
357 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs);
358 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts,
359 BlockDriverState *in_bs, Error **errp);
360 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
361 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp);
362 int bdrv_commit(BlockDriverState *bs);
363 int bdrv_change_backing_file(BlockDriverState *bs,
364 const char *backing_file, const char *backing_fmt);
365 void bdrv_register(BlockDriver *bdrv);
366 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base,
367 const char *backing_file_str);
368 BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
369 BlockDriverState *bs);
370 BlockDriverState *bdrv_find_base(BlockDriverState *bs);
371 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base,
372 Error **errp);
373 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base,
374 Error **errp);
375 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base);
378 typedef struct BdrvCheckResult {
379 int corruptions;
380 int leaks;
381 int check_errors;
382 int corruptions_fixed;
383 int leaks_fixed;
384 int64_t image_end_offset;
385 BlockFragInfo bfi;
386 } BdrvCheckResult;
388 typedef enum {
389 BDRV_FIX_LEAKS = 1,
390 BDRV_FIX_ERRORS = 2,
391 } BdrvCheckMode;
393 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
395 /* The units of offset and total_work_size may be chosen arbitrarily by the
396 * block driver; total_work_size may change during the course of the amendment
397 * operation */
398 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset,
399 int64_t total_work_size, void *opaque);
400 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts,
401 BlockDriverAmendStatusCB *status_cb, void *cb_opaque,
402 Error **errp);
404 /* external snapshots */
405 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,
406 BlockDriverState *candidate);
407 bool bdrv_is_first_non_filter(BlockDriverState *candidate);
409 /* check if a named node can be replaced when doing drive-mirror */
410 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs,
411 const char *node_name, Error **errp);
413 /* async block I/O */
414 void bdrv_aio_cancel(BlockAIOCB *acb);
415 void bdrv_aio_cancel_async(BlockAIOCB *acb);
417 /* sg packet commands */
418 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf);
420 /* Invalidate any cached metadata used by image formats */
421 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
422 void bdrv_invalidate_cache_all(Error **errp);
423 int bdrv_inactivate_all(void);
425 /* Ensure contents are flushed to disk. */
426 int bdrv_flush(BlockDriverState *bs);
427 int coroutine_fn bdrv_co_flush(BlockDriverState *bs);
428 int bdrv_flush_all(void);
429 void bdrv_close_all(void);
430 void bdrv_drain(BlockDriverState *bs);
431 void coroutine_fn bdrv_co_drain(BlockDriverState *bs);
432 void bdrv_drain_all_begin(void);
433 void bdrv_drain_all_end(void);
434 void bdrv_drain_all(void);
436 #define BDRV_POLL_WHILE(bs, cond) ({ \
437 BlockDriverState *bs_ = (bs); \
438 AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \
439 cond); })
441 int bdrv_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes);
442 int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes);
443 int bdrv_has_zero_init_1(BlockDriverState *bs);
444 int bdrv_has_zero_init(BlockDriverState *bs);
445 int bdrv_has_zero_init_truncate(BlockDriverState *bs);
446 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs);
447 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs);
448 int bdrv_block_status(BlockDriverState *bs, int64_t offset,
449 int64_t bytes, int64_t *pnum, int64_t *map,
450 BlockDriverState **file);
451 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base,
452 int64_t offset, int64_t bytes, int64_t *pnum,
453 int64_t *map, BlockDriverState **file);
454 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes,
455 int64_t *pnum);
456 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,
457 bool include_base, int64_t offset, int64_t bytes,
458 int64_t *pnum);
460 bool bdrv_is_read_only(BlockDriverState *bs);
461 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only,
462 bool ignore_allow_rdw, Error **errp);
463 int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg,
464 Error **errp);
465 bool bdrv_is_writable(BlockDriverState *bs);
466 bool bdrv_is_sg(BlockDriverState *bs);
467 bool bdrv_is_inserted(BlockDriverState *bs);
468 void bdrv_lock_medium(BlockDriverState *bs, bool locked);
469 void bdrv_eject(BlockDriverState *bs, bool eject_flag);
470 const char *bdrv_get_format_name(BlockDriverState *bs);
471 BlockDriverState *bdrv_find_node(const char *node_name);
472 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp);
473 XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp);
474 BlockDriverState *bdrv_lookup_bs(const char *device,
475 const char *node_name,
476 Error **errp);
477 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base);
478 BlockDriverState *bdrv_next_node(BlockDriverState *bs);
479 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs);
481 typedef struct BdrvNextIterator {
482 enum {
483 BDRV_NEXT_BACKEND_ROOTS,
484 BDRV_NEXT_MONITOR_OWNED,
485 } phase;
486 BlockBackend *blk;
487 BlockDriverState *bs;
488 } BdrvNextIterator;
490 BlockDriverState *bdrv_first(BdrvNextIterator *it);
491 BlockDriverState *bdrv_next(BdrvNextIterator *it);
492 void bdrv_next_cleanup(BdrvNextIterator *it);
494 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs);
495 bool bdrv_is_encrypted(BlockDriverState *bs);
496 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
497 void *opaque, bool read_only);
498 const char *bdrv_get_node_name(const BlockDriverState *bs);
499 const char *bdrv_get_device_name(const BlockDriverState *bs);
500 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs);
501 int bdrv_get_flags(BlockDriverState *bs);
502 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi);
503 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs,
504 Error **errp);
505 BlockStatsSpecific *bdrv_get_specific_stats(BlockDriverState *bs);
506 void bdrv_round_to_clusters(BlockDriverState *bs,
507 int64_t offset, int64_t bytes,
508 int64_t *cluster_offset,
509 int64_t *cluster_bytes);
511 void bdrv_get_backing_filename(BlockDriverState *bs,
512 char *filename, int filename_size);
513 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp);
514 char *bdrv_get_full_backing_filename_from_filename(const char *backed,
515 const char *backing,
516 Error **errp);
517 char *bdrv_dirname(BlockDriverState *bs, Error **errp);
519 int path_has_protocol(const char *path);
520 int path_is_absolute(const char *path);
521 char *path_combine(const char *base_path, const char *filename);
523 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
524 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
525 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
526 int64_t pos, int size);
528 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
529 int64_t pos, int size);
531 void bdrv_img_create(const char *filename, const char *fmt,
532 const char *base_filename, const char *base_fmt,
533 char *options, uint64_t img_size, int flags,
534 bool quiet, Error **errp);
536 /* Returns the alignment in bytes that is required so that no bounce buffer
537 * is required throughout the stack */
538 size_t bdrv_min_mem_align(BlockDriverState *bs);
539 /* Returns optimal alignment in bytes for bounce buffer */
540 size_t bdrv_opt_mem_align(BlockDriverState *bs);
541 void *qemu_blockalign(BlockDriverState *bs, size_t size);
542 void *qemu_blockalign0(BlockDriverState *bs, size_t size);
543 void *qemu_try_blockalign(BlockDriverState *bs, size_t size);
544 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size);
545 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);
547 void bdrv_enable_copy_on_read(BlockDriverState *bs);
548 void bdrv_disable_copy_on_read(BlockDriverState *bs);
550 void bdrv_ref(BlockDriverState *bs);
551 void bdrv_unref(BlockDriverState *bs);
552 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child);
553 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs,
554 BlockDriverState *child_bs,
555 const char *child_name,
556 const BdrvChildRole *child_role,
557 Error **errp);
559 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
560 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
561 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason);
562 void bdrv_op_block_all(BlockDriverState *bs, Error *reason);
563 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason);
564 bool bdrv_op_blocker_is_empty(BlockDriverState *bs);
566 #define BLKDBG_EVENT(child, evt) \
567 do { \
568 if (child) { \
569 bdrv_debug_event(child->bs, evt); \
571 } while (0)
573 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event);
575 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
576 const char *tag);
577 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag);
578 int bdrv_debug_resume(BlockDriverState *bs, const char *tag);
579 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag);
582 * bdrv_get_aio_context:
584 * Returns: the currently bound #AioContext
586 AioContext *bdrv_get_aio_context(BlockDriverState *bs);
589 * Transfer control to @co in the aio context of @bs
591 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co);
593 void bdrv_set_aio_context_ignore(BlockDriverState *bs,
594 AioContext *new_context, GSList **ignore);
595 int bdrv_try_set_aio_context(BlockDriverState *bs, AioContext *ctx,
596 Error **errp);
597 int bdrv_child_try_set_aio_context(BlockDriverState *bs, AioContext *ctx,
598 BdrvChild *ignore_child, Error **errp);
599 bool bdrv_child_can_set_aio_context(BdrvChild *c, AioContext *ctx,
600 GSList **ignore, Error **errp);
601 bool bdrv_can_set_aio_context(BlockDriverState *bs, AioContext *ctx,
602 GSList **ignore, Error **errp);
603 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz);
604 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo);
606 void bdrv_io_plug(BlockDriverState *bs);
607 void bdrv_io_unplug(BlockDriverState *bs);
610 * bdrv_parent_drained_begin_single:
612 * Begin a quiesced section for the parent of @c. If @poll is true, wait for
613 * any pending activity to cease.
615 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll);
618 * bdrv_parent_drained_end_single:
620 * End a quiesced section for the parent of @c.
622 * This polls @bs's AioContext until all scheduled sub-drained_ends
623 * have settled, which may result in graph changes.
625 void bdrv_parent_drained_end_single(BdrvChild *c);
628 * bdrv_drain_poll:
630 * Poll for pending requests in @bs, its parents (except for @ignore_parent),
631 * and if @recursive is true its children as well (used for subtree drain).
633 * If @ignore_bds_parents is true, parents that are BlockDriverStates must
634 * ignore the drain request because they will be drained separately (used for
635 * drain_all).
637 * This is part of bdrv_drained_begin.
639 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive,
640 BdrvChild *ignore_parent, bool ignore_bds_parents);
643 * bdrv_drained_begin:
645 * Begin a quiesced section for exclusive access to the BDS, by disabling
646 * external request sources including NBD server and device model. Note that
647 * this doesn't block timers or coroutines from submitting more requests, which
648 * means block_job_pause is still necessary.
650 * This function can be recursive.
652 void bdrv_drained_begin(BlockDriverState *bs);
655 * bdrv_do_drained_begin_quiesce:
657 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already
658 * running requests to complete.
660 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs,
661 BdrvChild *parent, bool ignore_bds_parents);
664 * Like bdrv_drained_begin, but recursively begins a quiesced section for
665 * exclusive access to all child nodes as well.
667 void bdrv_subtree_drained_begin(BlockDriverState *bs);
670 * bdrv_drained_end:
672 * End a quiescent section started by bdrv_drained_begin().
674 * This polls @bs's AioContext until all scheduled sub-drained_ends
675 * have settled. On one hand, that may result in graph changes. On
676 * the other, this requires that the caller either runs in the main
677 * loop; or that all involved nodes (@bs and all of its parents) are
678 * in the caller's AioContext.
680 void bdrv_drained_end(BlockDriverState *bs);
683 * bdrv_drained_end_no_poll:
685 * Same as bdrv_drained_end(), but do not poll for the subgraph to
686 * actually become unquiesced. Therefore, no graph changes will occur
687 * with this function.
689 * *drained_end_counter is incremented for every background operation
690 * that is scheduled, and will be decremented for every operation once
691 * it settles. The caller must poll until it reaches 0. The counter
692 * should be accessed using atomic operations only.
694 void bdrv_drained_end_no_poll(BlockDriverState *bs, int *drained_end_counter);
697 * End a quiescent section started by bdrv_subtree_drained_begin().
699 void bdrv_subtree_drained_end(BlockDriverState *bs);
701 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child,
702 Error **errp);
703 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp);
705 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name,
706 uint32_t granularity, Error **errp);
709 * bdrv_register_buf/bdrv_unregister_buf:
711 * Register/unregister a buffer for I/O. For example, VFIO drivers are
712 * interested to know the memory areas that would later be used for I/O, so
713 * that they can prepare IOMMU mapping etc., to get better performance.
715 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size);
716 void bdrv_unregister_buf(BlockDriverState *bs, void *host);
720 * bdrv_co_copy_range:
722 * Do offloaded copy between two children. If the operation is not implemented
723 * by the driver, or if the backend storage doesn't support it, a negative
724 * error code will be returned.
726 * Note: block layer doesn't emulate or fallback to a bounce buffer approach
727 * because usually the caller shouldn't attempt offloaded copy any more (e.g.
728 * calling copy_file_range(2)) after the first error, thus it should fall back
729 * to a read+write path in the caller level.
731 * @src: Source child to copy data from
732 * @src_offset: offset in @src image to read data
733 * @dst: Destination child to copy data to
734 * @dst_offset: offset in @dst image to write data
735 * @bytes: number of bytes to copy
736 * @flags: request flags. Supported flags:
737 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero
738 * write on @dst as if bdrv_co_pwrite_zeroes is
739 * called. Used to simplify caller code, or
740 * during BlockDriver.bdrv_co_copy_range_from()
741 * recursion.
742 * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping
743 * requests currently in flight.
745 * Returns: 0 if succeeded; negative error code if failed.
747 int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset,
748 BdrvChild *dst, uint64_t dst_offset,
749 uint64_t bytes, BdrvRequestFlags read_flags,
750 BdrvRequestFlags write_flags);
751 #endif