1 #ifndef BLOCK_H 2 #define BLOCK_H 3 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" 12 13 /* block.c */ 14 typedef struct BlockDriver BlockDriver; 15 typedef struct BdrvChild BdrvChild; 16 typedef struct BdrvChildRole BdrvChildRole; 17 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; 24 /* 25 * True if unallocated blocks read back as zeroes. This is equivalent 26 * to the LBPRZ flag in the SCSI logical block provisioning page. 27 */ 28 bool unallocated_blocks_are_zero; 29 /* 30 * True if this block driver only supports compressed writes 31 */ 32 bool needs_compressed_writes; 33 } BlockDriverInfo; 34 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; 41 42 typedef enum { 43 BDRV_REQ_COPY_ON_READ = 0x1, 44 BDRV_REQ_ZERO_WRITE = 0x2, 45 46 /* 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. 51 */ 52 BDRV_REQ_MAY_UNMAP = 0x4, 53 54 /* 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. 57 * 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). 64 */ 65 BDRV_REQ_NO_SERIALISING = 0x8, 66 BDRV_REQ_FUA = 0x10, 67 BDRV_REQ_WRITE_COMPRESSED = 0x20, 68 69 /* Signifies that this write request will not change the visible disk 70 * content. */ 71 BDRV_REQ_WRITE_UNCHANGED = 0x40, 72 73 /* 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. 78 * 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. 82 */ 83 BDRV_REQ_SERIALISING = 0x80, 84 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, 89 90 /* Mask of valid flags */ 91 BDRV_REQ_MASK = 0x1ff, 92 } BdrvRequestFlags; 93 94 typedef struct BlockSizes { 95 uint32_t phys; 96 uint32_t log; 97 } BlockSizes; 98 99 typedef struct HDGeometry { 100 uint32_t heads; 101 uint32_t sectors; 102 uint32_t cylinders; 103 } HDGeometry; 104 105 #define BDRV_O_RDWR 0x0002 106 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */ 107 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */ 108 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */ 109 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ 110 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */ 111 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */ 112 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */ 113 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */ 114 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */ 115 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */ 116 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */ 117 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */ 118 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given: 119 select an appropriate protocol driver, 120 ignoring the format layer */ 121 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */ 122 #define BDRV_O_AUTO_RDONLY 0x20000 /* degrade to read-only if opening read-write fails */ 123 124 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 125 126 127 /* Option names of options parsed by the block layer */ 128 129 #define BDRV_OPT_CACHE_WB "cache.writeback" 130 #define BDRV_OPT_CACHE_DIRECT "cache.direct" 131 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush" 132 #define BDRV_OPT_READ_ONLY "read-only" 133 #define BDRV_OPT_AUTO_READ_ONLY "auto-read-only" 134 #define BDRV_OPT_DISCARD "discard" 135 #define BDRV_OPT_FORCE_SHARE "force-share" 136 137 138 #define BDRV_SECTOR_BITS 9 139 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS) 140 #define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1) 141 142 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \ 143 INT_MAX >> BDRV_SECTOR_BITS) 144 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) 145 146 /* 147 * Allocation status flags for bdrv_block_status() and friends. 148 * 149 * Public flags: 150 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer 151 * BDRV_BLOCK_ZERO: offset reads as zero 152 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data 153 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this 154 * layer rather than any backing, set by block layer 155 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this 156 * layer, set by block layer 157 * 158 * Internal flags: 159 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request 160 * that the block layer recompute the answer from the returned 161 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID. 162 * BDRV_BLOCK_RECURSE: request that the block layer will recursively search for 163 * zeroes in file child of current block node inside 164 * returned region. Only valid together with both 165 * BDRV_BLOCK_DATA and BDRV_BLOCK_OFFSET_VALID. Should not 166 * appear with BDRV_BLOCK_ZERO. 167 * 168 * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the 169 * host offset within the returned BDS that is allocated for the 170 * corresponding raw guest data. However, whether that offset 171 * actually contains data also depends on BDRV_BLOCK_DATA, as follows: 172 * 173 * DATA ZERO OFFSET_VALID 174 * t t t sectors read as zero, returned file is zero at offset 175 * t f t sectors read as valid from file at offset 176 * f t t sectors preallocated, read as zero, returned file not 177 * necessarily zero at offset 178 * f f t sectors preallocated but read from backing_hd, 179 * returned file contains garbage at offset 180 * t t f sectors preallocated, read as zero, unknown offset 181 * t f f sectors read from unknown file or offset 182 * f t f not allocated or unknown offset, read as zero 183 * f f f not allocated or unknown offset, read from backing_hd 184 */ 185 #define BDRV_BLOCK_DATA 0x01 186 #define BDRV_BLOCK_ZERO 0x02 187 #define BDRV_BLOCK_OFFSET_VALID 0x04 188 #define BDRV_BLOCK_RAW 0x08 189 #define BDRV_BLOCK_ALLOCATED 0x10 190 #define BDRV_BLOCK_EOF 0x20 191 #define BDRV_BLOCK_RECURSE 0x40 192 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK 193 194 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 195 196 typedef struct BDRVReopenState { 197 BlockDriverState *bs; 198 int flags; 199 BlockdevDetectZeroesOptions detect_zeroes; 200 bool backing_missing; 201 bool replace_backing_bs; /* new_backing_bs is ignored if this is false */ 202 BlockDriverState *new_backing_bs; /* If NULL then detach the current bs */ 203 uint64_t perm, shared_perm; 204 QDict *options; 205 QDict *explicit_options; 206 void *opaque; 207 } BDRVReopenState; 208 209 /* 210 * Block operation types 211 */ 212 typedef enum BlockOpType { 213 BLOCK_OP_TYPE_BACKUP_SOURCE, 214 BLOCK_OP_TYPE_BACKUP_TARGET, 215 BLOCK_OP_TYPE_CHANGE, 216 BLOCK_OP_TYPE_COMMIT_SOURCE, 217 BLOCK_OP_TYPE_COMMIT_TARGET, 218 BLOCK_OP_TYPE_DATAPLANE, 219 BLOCK_OP_TYPE_DRIVE_DEL, 220 BLOCK_OP_TYPE_EJECT, 221 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, 222 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, 223 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, 224 BLOCK_OP_TYPE_MIRROR_SOURCE, 225 BLOCK_OP_TYPE_MIRROR_TARGET, 226 BLOCK_OP_TYPE_RESIZE, 227 BLOCK_OP_TYPE_STREAM, 228 BLOCK_OP_TYPE_REPLACE, 229 BLOCK_OP_TYPE_MAX, 230 } BlockOpType; 231 232 /* Block node permission constants */ 233 enum { 234 /** 235 * A user that has the "permission" of consistent reads is guaranteed that 236 * their view of the contents of the block device is complete and 237 * self-consistent, representing the contents of a disk at a specific 238 * point. 239 * 240 * For most block devices (including their backing files) this is true, but 241 * the property cannot be maintained in a few situations like for 242 * intermediate nodes of a commit block job. 243 */ 244 BLK_PERM_CONSISTENT_READ = 0x01, 245 246 /** This permission is required to change the visible disk contents. */ 247 BLK_PERM_WRITE = 0x02, 248 249 /** 250 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and 251 * required for writes to the block node when the caller promises that 252 * the visible disk content doesn't change. 253 * 254 * As the BLK_PERM_WRITE permission is strictly stronger, either is 255 * sufficient to perform an unchanging write. 256 */ 257 BLK_PERM_WRITE_UNCHANGED = 0x04, 258 259 /** This permission is required to change the size of a block node. */ 260 BLK_PERM_RESIZE = 0x08, 261 262 /** 263 * This permission is required to change the node that this BdrvChild 264 * points to. 265 */ 266 BLK_PERM_GRAPH_MOD = 0x10, 267 268 BLK_PERM_ALL = 0x1f, 269 270 DEFAULT_PERM_PASSTHROUGH = BLK_PERM_CONSISTENT_READ 271 | BLK_PERM_WRITE 272 | BLK_PERM_WRITE_UNCHANGED 273 | BLK_PERM_RESIZE, 274 275 DEFAULT_PERM_UNCHANGED = BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH, 276 }; 277 278 char *bdrv_perm_names(uint64_t perm); 279 280 /* disk I/O throttling */ 281 void bdrv_init(void); 282 void bdrv_init_with_whitelist(void); 283 bool bdrv_uses_whitelist(void); 284 int bdrv_is_whitelisted(BlockDriver *drv, bool read_only); 285 BlockDriver *bdrv_find_protocol(const char *filename, 286 bool allow_protocol_prefix, 287 Error **errp); 288 BlockDriver *bdrv_find_format(const char *format_name); 289 int bdrv_create(BlockDriver *drv, const char* filename, 290 QemuOpts *opts, Error **errp); 291 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 292 BlockDriverState *bdrv_new(void); 293 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 294 Error **errp); 295 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 296 Error **errp); 297 298 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough); 299 int bdrv_parse_discard_flags(const char *mode, int *flags); 300 BdrvChild *bdrv_open_child(const char *filename, 301 QDict *options, const char *bdref_key, 302 BlockDriverState* parent, 303 const BdrvChildRole *child_role, 304 bool allow_none, Error **errp); 305 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp); 306 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 307 Error **errp); 308 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 309 const char *bdref_key, Error **errp); 310 BlockDriverState *bdrv_open(const char *filename, const char *reference, 311 QDict *options, int flags, Error **errp); 312 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 313 int flags, Error **errp); 314 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 315 BlockDriverState *bs, QDict *options, 316 bool keep_old_opts); 317 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp); 318 int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, 319 Error **errp); 320 int bdrv_reopen_prepare(BDRVReopenState *reopen_state, 321 BlockReopenQueue *queue, Error **errp); 322 void bdrv_reopen_commit(BDRVReopenState *reopen_state); 323 void bdrv_reopen_abort(BDRVReopenState *reopen_state); 324 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, 325 int bytes, BdrvRequestFlags flags); 326 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); 327 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes); 328 int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 329 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes); 330 int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 331 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, 332 const void *buf, int count); 333 /* 334 * Efficiently zero a region of the disk image. Note that this is a regular 335 * I/O request like read or write and should have a reasonable size. This 336 * function is not suitable for zeroing the entire image in a single request 337 * because it may allocate memory for the entire region. 338 */ 339 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, 340 int bytes, BdrvRequestFlags flags); 341 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 342 const char *backing_file); 343 void bdrv_refresh_filename(BlockDriverState *bs); 344 345 int coroutine_fn bdrv_co_truncate(BdrvChild *child, int64_t offset, 346 PreallocMode prealloc, Error **errp); 347 int bdrv_truncate(BdrvChild *child, int64_t offset, PreallocMode prealloc, 348 Error **errp); 349 350 int64_t bdrv_nb_sectors(BlockDriverState *bs); 351 int64_t bdrv_getlength(BlockDriverState *bs); 352 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); 353 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, 354 BlockDriverState *in_bs, Error **errp); 355 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr); 356 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp); 357 int bdrv_commit(BlockDriverState *bs); 358 int bdrv_change_backing_file(BlockDriverState *bs, 359 const char *backing_file, const char *backing_fmt); 360 void bdrv_register(BlockDriver *bdrv); 361 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 362 const char *backing_file_str); 363 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 364 BlockDriverState *bs); 365 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 366 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base, 367 Error **errp); 368 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base, 369 Error **errp); 370 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base); 371 372 373 typedef struct BdrvCheckResult { 374 int corruptions; 375 int leaks; 376 int check_errors; 377 int corruptions_fixed; 378 int leaks_fixed; 379 int64_t image_end_offset; 380 BlockFragInfo bfi; 381 } BdrvCheckResult; 382 383 typedef enum { 384 BDRV_FIX_LEAKS = 1, 385 BDRV_FIX_ERRORS = 2, 386 } BdrvCheckMode; 387 388 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); 389 390 /* The units of offset and total_work_size may be chosen arbitrarily by the 391 * block driver; total_work_size may change during the course of the amendment 392 * operation */ 393 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 394 int64_t total_work_size, void *opaque); 395 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 396 BlockDriverAmendStatusCB *status_cb, void *cb_opaque, 397 Error **errp); 398 399 /* external snapshots */ 400 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs, 401 BlockDriverState *candidate); 402 bool bdrv_is_first_non_filter(BlockDriverState *candidate); 403 404 /* check if a named node can be replaced when doing drive-mirror */ 405 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 406 const char *node_name, Error **errp); 407 408 /* async block I/O */ 409 void bdrv_aio_cancel(BlockAIOCB *acb); 410 void bdrv_aio_cancel_async(BlockAIOCB *acb); 411 412 /* sg packet commands */ 413 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 414 415 /* Invalidate any cached metadata used by image formats */ 416 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp); 417 void bdrv_invalidate_cache_all(Error **errp); 418 int bdrv_inactivate_all(void); 419 420 /* Ensure contents are flushed to disk. */ 421 int bdrv_flush(BlockDriverState *bs); 422 int coroutine_fn bdrv_co_flush(BlockDriverState *bs); 423 int bdrv_flush_all(void); 424 void bdrv_close_all(void); 425 void bdrv_drain(BlockDriverState *bs); 426 void coroutine_fn bdrv_co_drain(BlockDriverState *bs); 427 void bdrv_drain_all_begin(void); 428 void bdrv_drain_all_end(void); 429 void bdrv_drain_all(void); 430 431 #define BDRV_POLL_WHILE(bs, cond) ({ \ 432 BlockDriverState *bs_ = (bs); \ 433 AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \ 434 cond); }) 435 436 int bdrv_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); 437 int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); 438 int bdrv_has_zero_init_1(BlockDriverState *bs); 439 int bdrv_has_zero_init(BlockDriverState *bs); 440 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs); 441 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); 442 int bdrv_block_status(BlockDriverState *bs, int64_t offset, 443 int64_t bytes, int64_t *pnum, int64_t *map, 444 BlockDriverState **file); 445 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, 446 int64_t offset, int64_t bytes, int64_t *pnum, 447 int64_t *map, BlockDriverState **file); 448 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, 449 int64_t *pnum); 450 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, 451 bool include_base, int64_t offset, int64_t bytes, 452 int64_t *pnum); 453 454 bool bdrv_is_read_only(BlockDriverState *bs); 455 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, 456 bool ignore_allow_rdw, Error **errp); 457 int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, 458 Error **errp); 459 bool bdrv_is_writable(BlockDriverState *bs); 460 bool bdrv_is_sg(BlockDriverState *bs); 461 bool bdrv_is_inserted(BlockDriverState *bs); 462 void bdrv_lock_medium(BlockDriverState *bs, bool locked); 463 void bdrv_eject(BlockDriverState *bs, bool eject_flag); 464 const char *bdrv_get_format_name(BlockDriverState *bs); 465 BlockDriverState *bdrv_find_node(const char *node_name); 466 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp); 467 XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp); 468 BlockDriverState *bdrv_lookup_bs(const char *device, 469 const char *node_name, 470 Error **errp); 471 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 472 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 473 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs); 474 475 typedef struct BdrvNextIterator { 476 enum { 477 BDRV_NEXT_BACKEND_ROOTS, 478 BDRV_NEXT_MONITOR_OWNED, 479 } phase; 480 BlockBackend *blk; 481 BlockDriverState *bs; 482 } BdrvNextIterator; 483 484 BlockDriverState *bdrv_first(BdrvNextIterator *it); 485 BlockDriverState *bdrv_next(BdrvNextIterator *it); 486 void bdrv_next_cleanup(BdrvNextIterator *it); 487 488 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 489 bool bdrv_is_encrypted(BlockDriverState *bs); 490 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 491 void *opaque, bool read_only); 492 const char *bdrv_get_node_name(const BlockDriverState *bs); 493 const char *bdrv_get_device_name(const BlockDriverState *bs); 494 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs); 495 int bdrv_get_flags(BlockDriverState *bs); 496 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); 497 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs, 498 Error **errp); 499 void bdrv_round_to_clusters(BlockDriverState *bs, 500 int64_t offset, int64_t bytes, 501 int64_t *cluster_offset, 502 int64_t *cluster_bytes); 503 504 void bdrv_get_backing_filename(BlockDriverState *bs, 505 char *filename, int filename_size); 506 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); 507 char *bdrv_get_full_backing_filename_from_filename(const char *backed, 508 const char *backing, 509 Error **errp); 510 char *bdrv_dirname(BlockDriverState *bs, Error **errp); 511 512 int path_has_protocol(const char *path); 513 int path_is_absolute(const char *path); 514 char *path_combine(const char *base_path, const char *filename); 515 516 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 517 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 518 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 519 int64_t pos, int size); 520 521 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 522 int64_t pos, int size); 523 524 void bdrv_img_create(const char *filename, const char *fmt, 525 const char *base_filename, const char *base_fmt, 526 char *options, uint64_t img_size, int flags, 527 bool quiet, Error **errp); 528 529 /* Returns the alignment in bytes that is required so that no bounce buffer 530 * is required throughout the stack */ 531 size_t bdrv_min_mem_align(BlockDriverState *bs); 532 /* Returns optimal alignment in bytes for bounce buffer */ 533 size_t bdrv_opt_mem_align(BlockDriverState *bs); 534 void *qemu_blockalign(BlockDriverState *bs, size_t size); 535 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 536 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 537 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 538 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 539 540 void bdrv_enable_copy_on_read(BlockDriverState *bs); 541 void bdrv_disable_copy_on_read(BlockDriverState *bs); 542 543 void bdrv_ref(BlockDriverState *bs); 544 void bdrv_unref(BlockDriverState *bs); 545 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 546 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 547 BlockDriverState *child_bs, 548 const char *child_name, 549 const BdrvChildRole *child_role, 550 Error **errp); 551 552 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 553 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 554 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 555 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 556 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 557 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 558 559 #define BLKDBG_EVENT(child, evt) \ 560 do { \ 561 if (child) { \ 562 bdrv_debug_event(child->bs, evt); \ 563 } \ 564 } while (0) 565 566 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 567 568 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 569 const char *tag); 570 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 571 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 572 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 573 574 /** 575 * bdrv_get_aio_context: 576 * 577 * Returns: the currently bound #AioContext 578 */ 579 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 580 581 /** 582 * Transfer control to @co in the aio context of @bs 583 */ 584 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 585 586 void bdrv_set_aio_context_ignore(BlockDriverState *bs, 587 AioContext *new_context, GSList **ignore); 588 int bdrv_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 589 Error **errp); 590 int bdrv_child_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 591 BdrvChild *ignore_child, Error **errp); 592 bool bdrv_child_can_set_aio_context(BdrvChild *c, AioContext *ctx, 593 GSList **ignore, Error **errp); 594 bool bdrv_can_set_aio_context(BlockDriverState *bs, AioContext *ctx, 595 GSList **ignore, Error **errp); 596 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 597 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 598 599 void bdrv_io_plug(BlockDriverState *bs); 600 void bdrv_io_unplug(BlockDriverState *bs); 601 602 /** 603 * bdrv_parent_drained_begin_single: 604 * 605 * Begin a quiesced section for the parent of @c. If @poll is true, wait for 606 * any pending activity to cease. 607 */ 608 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); 609 610 /** 611 * bdrv_parent_drained_end_single: 612 * 613 * End a quiesced section for the parent of @c. 614 * 615 * This polls @bs's AioContext until all scheduled sub-drained_ends 616 * have settled, which may result in graph changes. 617 */ 618 void bdrv_parent_drained_end_single(BdrvChild *c); 619 620 /** 621 * bdrv_drain_poll: 622 * 623 * Poll for pending requests in @bs, its parents (except for @ignore_parent), 624 * and if @recursive is true its children as well (used for subtree drain). 625 * 626 * If @ignore_bds_parents is true, parents that are BlockDriverStates must 627 * ignore the drain request because they will be drained separately (used for 628 * drain_all). 629 * 630 * This is part of bdrv_drained_begin. 631 */ 632 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, 633 BdrvChild *ignore_parent, bool ignore_bds_parents); 634 635 /** 636 * bdrv_drained_begin: 637 * 638 * Begin a quiesced section for exclusive access to the BDS, by disabling 639 * external request sources including NBD server and device model. Note that 640 * this doesn't block timers or coroutines from submitting more requests, which 641 * means block_job_pause is still necessary. 642 * 643 * This function can be recursive. 644 */ 645 void bdrv_drained_begin(BlockDriverState *bs); 646 647 /** 648 * bdrv_do_drained_begin_quiesce: 649 * 650 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already 651 * running requests to complete. 652 */ 653 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, 654 BdrvChild *parent, bool ignore_bds_parents); 655 656 /** 657 * Like bdrv_drained_begin, but recursively begins a quiesced section for 658 * exclusive access to all child nodes as well. 659 */ 660 void bdrv_subtree_drained_begin(BlockDriverState *bs); 661 662 /** 663 * bdrv_drained_end: 664 * 665 * End a quiescent section started by bdrv_drained_begin(). 666 * 667 * This polls @bs's AioContext until all scheduled sub-drained_ends 668 * have settled. On one hand, that may result in graph changes. On 669 * the other, this requires that the caller either runs in the main 670 * loop; or that all involved nodes (@bs and all of its parents) are 671 * in the caller's AioContext. 672 */ 673 void bdrv_drained_end(BlockDriverState *bs); 674 675 /** 676 * bdrv_drained_end_no_poll: 677 * 678 * Same as bdrv_drained_end(), but do not poll for the subgraph to 679 * actually become unquiesced. Therefore, no graph changes will occur 680 * with this function. 681 * 682 * *drained_end_counter is incremented for every background operation 683 * that is scheduled, and will be decremented for every operation once 684 * it settles. The caller must poll until it reaches 0. The counter 685 * should be accessed using atomic operations only. 686 */ 687 void bdrv_drained_end_no_poll(BlockDriverState *bs, int *drained_end_counter); 688 689 /** 690 * End a quiescent section started by bdrv_subtree_drained_begin(). 691 */ 692 void bdrv_subtree_drained_end(BlockDriverState *bs); 693 694 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 695 Error **errp); 696 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 697 698 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, 699 uint32_t granularity, Error **errp); 700 /** 701 * 702 * bdrv_register_buf/bdrv_unregister_buf: 703 * 704 * Register/unregister a buffer for I/O. For example, VFIO drivers are 705 * interested to know the memory areas that would later be used for I/O, so 706 * that they can prepare IOMMU mapping etc., to get better performance. 707 */ 708 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); 709 void bdrv_unregister_buf(BlockDriverState *bs, void *host); 710 711 /** 712 * 713 * bdrv_co_copy_range: 714 * 715 * Do offloaded copy between two children. If the operation is not implemented 716 * by the driver, or if the backend storage doesn't support it, a negative 717 * error code will be returned. 718 * 719 * Note: block layer doesn't emulate or fallback to a bounce buffer approach 720 * because usually the caller shouldn't attempt offloaded copy any more (e.g. 721 * calling copy_file_range(2)) after the first error, thus it should fall back 722 * to a read+write path in the caller level. 723 * 724 * @src: Source child to copy data from 725 * @src_offset: offset in @src image to read data 726 * @dst: Destination child to copy data to 727 * @dst_offset: offset in @dst image to write data 728 * @bytes: number of bytes to copy 729 * @flags: request flags. Supported flags: 730 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero 731 * write on @dst as if bdrv_co_pwrite_zeroes is 732 * called. Used to simplify caller code, or 733 * during BlockDriver.bdrv_co_copy_range_from() 734 * recursion. 735 * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping 736 * requests currently in flight. 737 * 738 * Returns: 0 if succeeded; negative error code if failed. 739 **/ 740 int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset, 741 BdrvChild *dst, uint64_t dst_offset, 742 uint64_t bytes, BdrvRequestFlags read_flags, 743 BdrvRequestFlags write_flags); 744 #endif 745