hw/s390x/ipl: avoid taking address of fields in packed struct
[qemu/ar7.git] / include / block / block.h
blobc7a26199aa07724a8160cc3383f3eda925ec9876
1 #ifndef BLOCK_H
2 #define BLOCK_H
4 #include "block/aio.h"
5 #include "qapi/qapi-types-block-core.h"
6 #include "block/aio-wait.h"
7 #include "qemu/iov.h"
8 #include "qemu/coroutine.h"
9 #include "block/accounting.h"
10 #include "block/dirty-bitmap.h"
11 #include "block/blockjob.h"
12 #include "qemu/hbitmap.h"
14 /* block.c */
15 typedef struct BlockDriver BlockDriver;
16 typedef struct BdrvChild BdrvChild;
17 typedef struct BdrvChildRole BdrvChildRole;
19 typedef struct BlockDriverInfo {
20 /* in bytes, 0 if irrelevant */
21 int cluster_size;
22 /* offset at which the VM state can be saved (0 if not possible) */
23 int64_t vm_state_offset;
24 bool is_dirty;
26 * True if unallocated blocks read back as zeroes. This is equivalent
27 * to the LBPRZ flag in the SCSI logical block provisioning page.
29 bool unallocated_blocks_are_zero;
31 * True if this block driver only supports compressed writes
33 bool needs_compressed_writes;
34 } BlockDriverInfo;
36 typedef struct BlockFragInfo {
37 uint64_t allocated_clusters;
38 uint64_t total_clusters;
39 uint64_t fragmented_clusters;
40 uint64_t compressed_clusters;
41 } BlockFragInfo;
43 typedef enum {
44 BDRV_REQ_COPY_ON_READ = 0x1,
45 BDRV_REQ_ZERO_WRITE = 0x2,
48 * The BDRV_REQ_MAY_UNMAP flag is used in write_zeroes requests to indicate
49 * that the block driver should unmap (discard) blocks if it is guaranteed
50 * that the result will read back as zeroes. The flag is only passed to the
51 * driver if the block device is opened with BDRV_O_UNMAP.
53 BDRV_REQ_MAY_UNMAP = 0x4,
56 * The BDRV_REQ_NO_SERIALISING flag is only valid for reads and means that
57 * we don't want wait_serialising_requests() during the read operation.
59 * This flag is used for backup copy-on-write operations, when we need to
60 * read old data before write (write notifier triggered). It is okay since
61 * we already waited for other serializing requests in the initiating write
62 * (see bdrv_aligned_pwritev), and it is necessary if the initiating write
63 * is already serializing (without the flag, the read would deadlock
64 * waiting for the serialising write to complete).
66 BDRV_REQ_NO_SERIALISING = 0x8,
67 BDRV_REQ_FUA = 0x10,
68 BDRV_REQ_WRITE_COMPRESSED = 0x20,
70 /* Signifies that this write request will not change the visible disk
71 * content. */
72 BDRV_REQ_WRITE_UNCHANGED = 0x40,
75 * BDRV_REQ_SERIALISING forces request serialisation for writes.
76 * It is used to ensure that writes to the backing file of a backup process
77 * target cannot race with a read of the backup target that defers to the
78 * backing file.
80 * Note, that BDRV_REQ_SERIALISING is _not_ opposite in meaning to
81 * BDRV_REQ_NO_SERIALISING. A more descriptive name for the latter might be
82 * _DO_NOT_WAIT_FOR_SERIALISING, except that is too long.
84 BDRV_REQ_SERIALISING = 0x80,
86 /* Execute the request only if the operation can be offloaded or otherwise
87 * be executed efficiently, but return an error instead of using a slow
88 * fallback. */
89 BDRV_REQ_NO_FALLBACK = 0x100,
91 /* Mask of valid flags */
92 BDRV_REQ_MASK = 0x1ff,
93 } BdrvRequestFlags;
95 typedef struct BlockSizes {
96 uint32_t phys;
97 uint32_t log;
98 } BlockSizes;
100 typedef struct HDGeometry {
101 uint32_t heads;
102 uint32_t sectors;
103 uint32_t cylinders;
104 } HDGeometry;
106 #define BDRV_O_RDWR 0x0002
107 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */
108 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */
109 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */
110 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */
111 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */
112 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */
113 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */
114 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
115 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */
116 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */
117 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */
118 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */
119 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given:
120 select an appropriate protocol driver,
121 ignoring the format layer */
122 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */
123 #define BDRV_O_AUTO_RDONLY 0x20000 /* degrade to read-only if opening read-write fails */
125 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH)
128 /* Option names of options parsed by the block layer */
130 #define BDRV_OPT_CACHE_WB "cache.writeback"
131 #define BDRV_OPT_CACHE_DIRECT "cache.direct"
132 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush"
133 #define BDRV_OPT_READ_ONLY "read-only"
134 #define BDRV_OPT_AUTO_READ_ONLY "auto-read-only"
135 #define BDRV_OPT_DISCARD "discard"
136 #define BDRV_OPT_FORCE_SHARE "force-share"
139 #define BDRV_SECTOR_BITS 9
140 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS)
141 #define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1)
143 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \
144 INT_MAX >> BDRV_SECTOR_BITS)
145 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS)
148 * Allocation status flags for bdrv_block_status() and friends.
150 * Public flags:
151 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer
152 * BDRV_BLOCK_ZERO: offset reads as zero
153 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data
154 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
155 * layer rather than any backing, set by block layer
156 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this
157 * layer, set by block layer
159 * Internal flag:
160 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request
161 * that the block layer recompute the answer from the returned
162 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID.
164 * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the
165 * host offset within the returned BDS that is allocated for the
166 * corresponding raw guest data. However, whether that offset
167 * actually contains data also depends on BDRV_BLOCK_DATA, as follows:
169 * DATA ZERO OFFSET_VALID
170 * t t t sectors read as zero, returned file is zero at offset
171 * t f t sectors read as valid from file at offset
172 * f t t sectors preallocated, read as zero, returned file not
173 * necessarily zero at offset
174 * f f t sectors preallocated but read from backing_hd,
175 * returned file contains garbage at offset
176 * t t f sectors preallocated, read as zero, unknown offset
177 * t f f sectors read from unknown file or offset
178 * f t f not allocated or unknown offset, read as zero
179 * f f f not allocated or unknown offset, read from backing_hd
181 #define BDRV_BLOCK_DATA 0x01
182 #define BDRV_BLOCK_ZERO 0x02
183 #define BDRV_BLOCK_OFFSET_VALID 0x04
184 #define BDRV_BLOCK_RAW 0x08
185 #define BDRV_BLOCK_ALLOCATED 0x10
186 #define BDRV_BLOCK_EOF 0x20
187 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK
189 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue;
191 typedef struct BDRVReopenState {
192 BlockDriverState *bs;
193 int flags;
194 BlockdevDetectZeroesOptions detect_zeroes;
195 bool backing_missing;
196 bool replace_backing_bs; /* new_backing_bs is ignored if this is false */
197 BlockDriverState *new_backing_bs; /* If NULL then detach the current bs */
198 uint64_t perm, shared_perm;
199 QDict *options;
200 QDict *explicit_options;
201 void *opaque;
202 } BDRVReopenState;
205 * Block operation types
207 typedef enum BlockOpType {
208 BLOCK_OP_TYPE_BACKUP_SOURCE,
209 BLOCK_OP_TYPE_BACKUP_TARGET,
210 BLOCK_OP_TYPE_CHANGE,
211 BLOCK_OP_TYPE_COMMIT_SOURCE,
212 BLOCK_OP_TYPE_COMMIT_TARGET,
213 BLOCK_OP_TYPE_DATAPLANE,
214 BLOCK_OP_TYPE_DRIVE_DEL,
215 BLOCK_OP_TYPE_EJECT,
216 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
217 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT,
218 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE,
219 BLOCK_OP_TYPE_MIRROR_SOURCE,
220 BLOCK_OP_TYPE_MIRROR_TARGET,
221 BLOCK_OP_TYPE_RESIZE,
222 BLOCK_OP_TYPE_STREAM,
223 BLOCK_OP_TYPE_REPLACE,
224 BLOCK_OP_TYPE_MAX,
225 } BlockOpType;
227 /* Block node permission constants */
228 enum {
230 * A user that has the "permission" of consistent reads is guaranteed that
231 * their view of the contents of the block device is complete and
232 * self-consistent, representing the contents of a disk at a specific
233 * point.
235 * For most block devices (including their backing files) this is true, but
236 * the property cannot be maintained in a few situations like for
237 * intermediate nodes of a commit block job.
239 BLK_PERM_CONSISTENT_READ = 0x01,
241 /** This permission is required to change the visible disk contents. */
242 BLK_PERM_WRITE = 0x02,
245 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and
246 * required for writes to the block node when the caller promises that
247 * the visible disk content doesn't change.
249 * As the BLK_PERM_WRITE permission is strictly stronger, either is
250 * sufficient to perform an unchanging write.
252 BLK_PERM_WRITE_UNCHANGED = 0x04,
254 /** This permission is required to change the size of a block node. */
255 BLK_PERM_RESIZE = 0x08,
258 * This permission is required to change the node that this BdrvChild
259 * points to.
261 BLK_PERM_GRAPH_MOD = 0x10,
263 BLK_PERM_ALL = 0x1f,
265 DEFAULT_PERM_PASSTHROUGH = BLK_PERM_CONSISTENT_READ
266 | BLK_PERM_WRITE
267 | BLK_PERM_WRITE_UNCHANGED
268 | BLK_PERM_RESIZE,
270 DEFAULT_PERM_UNCHANGED = BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH,
273 char *bdrv_perm_names(uint64_t perm);
275 /* disk I/O throttling */
276 void bdrv_init(void);
277 void bdrv_init_with_whitelist(void);
278 bool bdrv_uses_whitelist(void);
279 int bdrv_is_whitelisted(BlockDriver *drv, bool read_only);
280 BlockDriver *bdrv_find_protocol(const char *filename,
281 bool allow_protocol_prefix,
282 Error **errp);
283 BlockDriver *bdrv_find_format(const char *format_name);
284 int bdrv_create(BlockDriver *drv, const char* filename,
285 QemuOpts *opts, Error **errp);
286 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp);
287 BlockDriverState *bdrv_new(void);
288 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top,
289 Error **errp);
290 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to,
291 Error **errp);
293 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough);
294 int bdrv_parse_discard_flags(const char *mode, int *flags);
295 BdrvChild *bdrv_open_child(const char *filename,
296 QDict *options, const char *bdref_key,
297 BlockDriverState* parent,
298 const BdrvChildRole *child_role,
299 bool allow_none, Error **errp);
300 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp);
301 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd,
302 Error **errp);
303 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options,
304 const char *bdref_key, Error **errp);
305 BlockDriverState *bdrv_open(const char *filename, const char *reference,
306 QDict *options, int flags, Error **errp);
307 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name,
308 int flags, Error **errp);
309 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
310 BlockDriverState *bs, QDict *options,
311 bool keep_old_opts);
312 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp);
313 int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only,
314 Error **errp);
315 int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
316 BlockReopenQueue *queue, Error **errp);
317 void bdrv_reopen_commit(BDRVReopenState *reopen_state);
318 void bdrv_reopen_abort(BDRVReopenState *reopen_state);
319 int bdrv_read(BdrvChild *child, int64_t sector_num,
320 uint8_t *buf, int nb_sectors);
321 int bdrv_write(BdrvChild *child, int64_t sector_num,
322 const uint8_t *buf, int nb_sectors);
323 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
324 int bytes, BdrvRequestFlags flags);
325 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags);
326 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes);
327 int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov);
328 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes);
329 int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov);
330 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset,
331 const void *buf, int count);
333 * Efficiently zero a region of the disk image. Note that this is a regular
334 * I/O request like read or write and should have a reasonable size. This
335 * function is not suitable for zeroing the entire image in a single request
336 * because it may allocate memory for the entire region.
338 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset,
339 int bytes, BdrvRequestFlags flags);
340 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
341 const char *backing_file);
342 void bdrv_refresh_filename(BlockDriverState *bs);
344 int coroutine_fn bdrv_co_truncate(BdrvChild *child, int64_t offset,
345 PreallocMode prealloc, Error **errp);
346 int bdrv_truncate(BdrvChild *child, int64_t offset, PreallocMode prealloc,
347 Error **errp);
349 int64_t bdrv_nb_sectors(BlockDriverState *bs);
350 int64_t bdrv_getlength(BlockDriverState *bs);
351 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs);
352 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts,
353 BlockDriverState *in_bs, Error **errp);
354 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
355 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp);
356 int bdrv_commit(BlockDriverState *bs);
357 int bdrv_change_backing_file(BlockDriverState *bs,
358 const char *backing_file, const char *backing_fmt);
359 void bdrv_register(BlockDriver *bdrv);
360 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base,
361 const char *backing_file_str);
362 BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
363 BlockDriverState *bs);
364 BlockDriverState *bdrv_find_base(BlockDriverState *bs);
365 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base,
366 Error **errp);
367 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base,
368 Error **errp);
369 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base);
372 typedef struct BdrvCheckResult {
373 int corruptions;
374 int leaks;
375 int check_errors;
376 int corruptions_fixed;
377 int leaks_fixed;
378 int64_t image_end_offset;
379 BlockFragInfo bfi;
380 } BdrvCheckResult;
382 typedef enum {
383 BDRV_FIX_LEAKS = 1,
384 BDRV_FIX_ERRORS = 2,
385 } BdrvCheckMode;
387 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
389 /* The units of offset and total_work_size may be chosen arbitrarily by the
390 * block driver; total_work_size may change during the course of the amendment
391 * operation */
392 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset,
393 int64_t total_work_size, void *opaque);
394 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts,
395 BlockDriverAmendStatusCB *status_cb, void *cb_opaque,
396 Error **errp);
398 /* external snapshots */
399 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,
400 BlockDriverState *candidate);
401 bool bdrv_is_first_non_filter(BlockDriverState *candidate);
403 /* check if a named node can be replaced when doing drive-mirror */
404 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs,
405 const char *node_name, Error **errp);
407 /* async block I/O */
408 void bdrv_aio_cancel(BlockAIOCB *acb);
409 void bdrv_aio_cancel_async(BlockAIOCB *acb);
411 /* sg packet commands */
412 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf);
414 /* Invalidate any cached metadata used by image formats */
415 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
416 void bdrv_invalidate_cache_all(Error **errp);
417 int bdrv_inactivate_all(void);
419 /* Ensure contents are flushed to disk. */
420 int bdrv_flush(BlockDriverState *bs);
421 int coroutine_fn bdrv_co_flush(BlockDriverState *bs);
422 int bdrv_flush_all(void);
423 void bdrv_close_all(void);
424 void bdrv_drain(BlockDriverState *bs);
425 void coroutine_fn bdrv_co_drain(BlockDriverState *bs);
426 void bdrv_drain_all_begin(void);
427 void bdrv_drain_all_end(void);
428 void bdrv_drain_all(void);
430 #define BDRV_POLL_WHILE(bs, cond) ({ \
431 BlockDriverState *bs_ = (bs); \
432 AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \
433 cond); })
435 int bdrv_pdiscard(BdrvChild *child, int64_t offset, int bytes);
436 int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int bytes);
437 int bdrv_has_zero_init_1(BlockDriverState *bs);
438 int bdrv_has_zero_init(BlockDriverState *bs);
439 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs);
440 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs);
441 int bdrv_block_status(BlockDriverState *bs, int64_t offset,
442 int64_t bytes, int64_t *pnum, int64_t *map,
443 BlockDriverState **file);
444 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base,
445 int64_t offset, int64_t bytes, int64_t *pnum,
446 int64_t *map, BlockDriverState **file);
447 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes,
448 int64_t *pnum);
449 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,
450 int64_t offset, int64_t bytes, int64_t *pnum);
452 bool bdrv_is_read_only(BlockDriverState *bs);
453 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only,
454 bool ignore_allow_rdw, Error **errp);
455 int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg,
456 Error **errp);
457 bool bdrv_is_writable(BlockDriverState *bs);
458 bool bdrv_is_sg(BlockDriverState *bs);
459 bool bdrv_is_inserted(BlockDriverState *bs);
460 void bdrv_lock_medium(BlockDriverState *bs, bool locked);
461 void bdrv_eject(BlockDriverState *bs, bool eject_flag);
462 const char *bdrv_get_format_name(BlockDriverState *bs);
463 BlockDriverState *bdrv_find_node(const char *node_name);
464 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp);
465 XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp);
466 BlockDriverState *bdrv_lookup_bs(const char *device,
467 const char *node_name,
468 Error **errp);
469 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base);
470 BlockDriverState *bdrv_next_node(BlockDriverState *bs);
471 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs);
473 typedef struct BdrvNextIterator {
474 enum {
475 BDRV_NEXT_BACKEND_ROOTS,
476 BDRV_NEXT_MONITOR_OWNED,
477 } phase;
478 BlockBackend *blk;
479 BlockDriverState *bs;
480 } BdrvNextIterator;
482 BlockDriverState *bdrv_first(BdrvNextIterator *it);
483 BlockDriverState *bdrv_next(BdrvNextIterator *it);
484 void bdrv_next_cleanup(BdrvNextIterator *it);
486 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs);
487 bool bdrv_is_encrypted(BlockDriverState *bs);
488 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
489 void *opaque, bool read_only);
490 const char *bdrv_get_node_name(const BlockDriverState *bs);
491 const char *bdrv_get_device_name(const BlockDriverState *bs);
492 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs);
493 int bdrv_get_flags(BlockDriverState *bs);
494 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi);
495 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs,
496 Error **errp);
497 void bdrv_round_to_clusters(BlockDriverState *bs,
498 int64_t offset, int64_t bytes,
499 int64_t *cluster_offset,
500 int64_t *cluster_bytes);
502 void bdrv_get_backing_filename(BlockDriverState *bs,
503 char *filename, int filename_size);
504 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp);
505 char *bdrv_get_full_backing_filename_from_filename(const char *backed,
506 const char *backing,
507 Error **errp);
508 char *bdrv_dirname(BlockDriverState *bs, Error **errp);
510 int path_has_protocol(const char *path);
511 int path_is_absolute(const char *path);
512 char *path_combine(const char *base_path, const char *filename);
514 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
515 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
516 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
517 int64_t pos, int size);
519 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
520 int64_t pos, int size);
522 void bdrv_img_create(const char *filename, const char *fmt,
523 const char *base_filename, const char *base_fmt,
524 char *options, uint64_t img_size, int flags,
525 bool quiet, Error **errp);
527 /* Returns the alignment in bytes that is required so that no bounce buffer
528 * is required throughout the stack */
529 size_t bdrv_min_mem_align(BlockDriverState *bs);
530 /* Returns optimal alignment in bytes for bounce buffer */
531 size_t bdrv_opt_mem_align(BlockDriverState *bs);
532 void *qemu_blockalign(BlockDriverState *bs, size_t size);
533 void *qemu_blockalign0(BlockDriverState *bs, size_t size);
534 void *qemu_try_blockalign(BlockDriverState *bs, size_t size);
535 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size);
536 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);
538 void bdrv_enable_copy_on_read(BlockDriverState *bs);
539 void bdrv_disable_copy_on_read(BlockDriverState *bs);
541 void bdrv_ref(BlockDriverState *bs);
542 void bdrv_unref(BlockDriverState *bs);
543 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child);
544 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs,
545 BlockDriverState *child_bs,
546 const char *child_name,
547 const BdrvChildRole *child_role,
548 Error **errp);
550 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
551 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
552 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason);
553 void bdrv_op_block_all(BlockDriverState *bs, Error *reason);
554 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason);
555 bool bdrv_op_blocker_is_empty(BlockDriverState *bs);
557 #define BLKDBG_EVENT(child, evt) \
558 do { \
559 if (child) { \
560 bdrv_debug_event(child->bs, evt); \
562 } while (0)
564 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event);
566 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
567 const char *tag);
568 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag);
569 int bdrv_debug_resume(BlockDriverState *bs, const char *tag);
570 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag);
573 * bdrv_get_aio_context:
575 * Returns: the currently bound #AioContext
577 AioContext *bdrv_get_aio_context(BlockDriverState *bs);
580 * Transfer control to @co in the aio context of @bs
582 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co);
585 * bdrv_set_aio_context:
587 * Changes the #AioContext used for fd handlers, timers, and BHs by this
588 * BlockDriverState and all its children.
590 * This function must be called with iothread lock held.
592 void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context);
593 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz);
594 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo);
596 void bdrv_io_plug(BlockDriverState *bs);
597 void bdrv_io_unplug(BlockDriverState *bs);
600 * bdrv_parent_drained_begin:
602 * Begin a quiesced section of all users of @bs. This is part of
603 * bdrv_drained_begin.
605 void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore,
606 bool ignore_bds_parents);
609 * bdrv_parent_drained_begin_single:
611 * Begin a quiesced section for the parent of @c. If @poll is true, wait for
612 * any pending activity to cease.
614 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll);
617 * bdrv_parent_drained_end:
619 * End a quiesced section of all users of @bs. This is part of
620 * bdrv_drained_end.
622 void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore,
623 bool ignore_bds_parents);
626 * bdrv_drain_poll:
628 * Poll for pending requests in @bs, its parents (except for @ignore_parent),
629 * and if @recursive is true its children as well (used for subtree drain).
631 * If @ignore_bds_parents is true, parents that are BlockDriverStates must
632 * ignore the drain request because they will be drained separately (used for
633 * drain_all).
635 * This is part of bdrv_drained_begin.
637 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive,
638 BdrvChild *ignore_parent, bool ignore_bds_parents);
641 * bdrv_drained_begin:
643 * Begin a quiesced section for exclusive access to the BDS, by disabling
644 * external request sources including NBD server and device model. Note that
645 * this doesn't block timers or coroutines from submitting more requests, which
646 * means block_job_pause is still necessary.
648 * This function can be recursive.
650 void bdrv_drained_begin(BlockDriverState *bs);
653 * bdrv_do_drained_begin_quiesce:
655 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already
656 * running requests to complete.
658 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs,
659 BdrvChild *parent, bool ignore_bds_parents);
662 * Like bdrv_drained_begin, but recursively begins a quiesced section for
663 * exclusive access to all child nodes as well.
665 void bdrv_subtree_drained_begin(BlockDriverState *bs);
668 * bdrv_drained_end:
670 * End a quiescent section started by bdrv_drained_begin().
672 void bdrv_drained_end(BlockDriverState *bs);
675 * End a quiescent section started by bdrv_subtree_drained_begin().
677 void bdrv_subtree_drained_end(BlockDriverState *bs);
679 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child,
680 Error **errp);
681 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp);
683 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name,
684 uint32_t granularity, Error **errp);
687 * bdrv_register_buf/bdrv_unregister_buf:
689 * Register/unregister a buffer for I/O. For example, VFIO drivers are
690 * interested to know the memory areas that would later be used for I/O, so
691 * that they can prepare IOMMU mapping etc., to get better performance.
693 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size);
694 void bdrv_unregister_buf(BlockDriverState *bs, void *host);
698 * bdrv_co_copy_range:
700 * Do offloaded copy between two children. If the operation is not implemented
701 * by the driver, or if the backend storage doesn't support it, a negative
702 * error code will be returned.
704 * Note: block layer doesn't emulate or fallback to a bounce buffer approach
705 * because usually the caller shouldn't attempt offloaded copy any more (e.g.
706 * calling copy_file_range(2)) after the first error, thus it should fall back
707 * to a read+write path in the caller level.
709 * @src: Source child to copy data from
710 * @src_offset: offset in @src image to read data
711 * @dst: Destination child to copy data to
712 * @dst_offset: offset in @dst image to write data
713 * @bytes: number of bytes to copy
714 * @flags: request flags. Supported flags:
715 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero
716 * write on @dst as if bdrv_co_pwrite_zeroes is
717 * called. Used to simplify caller code, or
718 * during BlockDriver.bdrv_co_copy_range_from()
719 * recursion.
720 * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping
721 * requests currently in flight.
723 * Returns: 0 if succeeded; negative error code if failed.
725 int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset,
726 BdrvChild *dst, uint64_t dst_offset,
727 uint64_t bytes, BdrvRequestFlags read_flags,
728 BdrvRequestFlags write_flags);
729 #endif