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 /* 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. 94 */ 95 BDRV_REQ_PREFETCH = 0x200, 96 /* Mask of valid flags */ 97 BDRV_REQ_MASK = 0x3ff, 98 } BdrvRequestFlags; 99 100 typedef struct BlockSizes { 101 uint32_t phys; 102 uint32_t log; 103 } BlockSizes; 104 105 typedef struct HDGeometry { 106 uint32_t heads; 107 uint32_t sectors; 108 uint32_t cylinders; 109 } HDGeometry; 110 111 #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 */ 129 130 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 131 132 133 /* Option names of options parsed by the block layer */ 134 135 #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" 142 143 144 #define BDRV_SECTOR_BITS 9 145 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS) 146 147 #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) 150 151 /* 152 * Allocation status flags for bdrv_block_status() and friends. 153 * 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 162 * 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. 172 * 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: 177 * 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 189 */ 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 197 198 typedef QTAILQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 199 200 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; 212 213 /* 214 * Block operation types 215 */ 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; 235 236 /* Block node permission constants */ 237 enum { 238 /** 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. 243 * 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. 247 */ 248 BLK_PERM_CONSISTENT_READ = 0x01, 249 250 /** This permission is required to change the visible disk contents. */ 251 BLK_PERM_WRITE = 0x02, 252 253 /** 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. 257 * 258 * As the BLK_PERM_WRITE permission is strictly stronger, either is 259 * sufficient to perform an unchanging write. 260 */ 261 BLK_PERM_WRITE_UNCHANGED = 0x04, 262 263 /** This permission is required to change the size of a block node. */ 264 BLK_PERM_RESIZE = 0x08, 265 266 /** 267 * This permission is required to change the node that this BdrvChild 268 * points to. 269 */ 270 BLK_PERM_GRAPH_MOD = 0x10, 271 272 BLK_PERM_ALL = 0x1f, 273 274 DEFAULT_PERM_PASSTHROUGH = BLK_PERM_CONSISTENT_READ 275 | BLK_PERM_WRITE 276 | BLK_PERM_WRITE_UNCHANGED 277 | BLK_PERM_RESIZE, 278 279 DEFAULT_PERM_UNCHANGED = BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH, 280 }; 281 282 char *bdrv_perm_names(uint64_t perm); 283 uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm); 284 285 /* 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); 302 303 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); 338 /* 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. 343 */ 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); 349 350 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); 354 355 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); 376 377 378 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; 387 388 typedef enum { 389 BDRV_FIX_LEAKS = 1, 390 BDRV_FIX_ERRORS = 2, 391 } BdrvCheckMode; 392 393 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); 394 395 /* 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); 403 404 /* external snapshots */ 405 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs, 406 BlockDriverState *candidate); 407 bool bdrv_is_first_non_filter(BlockDriverState *candidate); 408 409 /* 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); 412 413 /* async block I/O */ 414 void bdrv_aio_cancel(BlockAIOCB *acb); 415 void bdrv_aio_cancel_async(BlockAIOCB *acb); 416 417 /* sg packet commands */ 418 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 419 420 /* 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); 424 425 /* 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); 435 436 #define BDRV_POLL_WHILE(bs, cond) ({ \ 437 BlockDriverState *bs_ = (bs); \ 438 AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \ 439 cond); }) 440 441 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); 459 460 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); 480 481 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; 489 490 BlockDriverState *bdrv_first(BdrvNextIterator *it); 491 BlockDriverState *bdrv_next(BdrvNextIterator *it); 492 void bdrv_next_cleanup(BdrvNextIterator *it); 493 494 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); 510 511 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); 518 519 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); 522 523 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); 527 528 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 529 int64_t pos, int size); 530 531 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); 535 536 /* 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); 546 547 void bdrv_enable_copy_on_read(BlockDriverState *bs); 548 void bdrv_disable_copy_on_read(BlockDriverState *bs); 549 550 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); 558 559 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); 565 566 #define BLKDBG_EVENT(child, evt) \ 567 do { \ 568 if (child) { \ 569 bdrv_debug_event(child->bs, evt); \ 570 } \ 571 } while (0) 572 573 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 574 575 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); 580 581 /** 582 * bdrv_get_aio_context: 583 * 584 * Returns: the currently bound #AioContext 585 */ 586 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 587 588 /** 589 * Transfer control to @co in the aio context of @bs 590 */ 591 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 592 593 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); 605 606 void bdrv_io_plug(BlockDriverState *bs); 607 void bdrv_io_unplug(BlockDriverState *bs); 608 609 /** 610 * bdrv_parent_drained_begin_single: 611 * 612 * Begin a quiesced section for the parent of @c. If @poll is true, wait for 613 * any pending activity to cease. 614 */ 615 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); 616 617 /** 618 * bdrv_parent_drained_end_single: 619 * 620 * End a quiesced section for the parent of @c. 621 * 622 * This polls @bs's AioContext until all scheduled sub-drained_ends 623 * have settled, which may result in graph changes. 624 */ 625 void bdrv_parent_drained_end_single(BdrvChild *c); 626 627 /** 628 * bdrv_drain_poll: 629 * 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). 632 * 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). 636 * 637 * This is part of bdrv_drained_begin. 638 */ 639 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, 640 BdrvChild *ignore_parent, bool ignore_bds_parents); 641 642 /** 643 * bdrv_drained_begin: 644 * 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. 649 * 650 * This function can be recursive. 651 */ 652 void bdrv_drained_begin(BlockDriverState *bs); 653 654 /** 655 * bdrv_do_drained_begin_quiesce: 656 * 657 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already 658 * running requests to complete. 659 */ 660 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, 661 BdrvChild *parent, bool ignore_bds_parents); 662 663 /** 664 * Like bdrv_drained_begin, but recursively begins a quiesced section for 665 * exclusive access to all child nodes as well. 666 */ 667 void bdrv_subtree_drained_begin(BlockDriverState *bs); 668 669 /** 670 * bdrv_drained_end: 671 * 672 * End a quiescent section started by bdrv_drained_begin(). 673 * 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. 679 */ 680 void bdrv_drained_end(BlockDriverState *bs); 681 682 /** 683 * bdrv_drained_end_no_poll: 684 * 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. 688 * 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. 693 */ 694 void bdrv_drained_end_no_poll(BlockDriverState *bs, int *drained_end_counter); 695 696 /** 697 * End a quiescent section started by bdrv_subtree_drained_begin(). 698 */ 699 void bdrv_subtree_drained_end(BlockDriverState *bs); 700 701 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 702 Error **errp); 703 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 704 705 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, 706 uint32_t granularity, Error **errp); 707 /** 708 * 709 * bdrv_register_buf/bdrv_unregister_buf: 710 * 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. 714 */ 715 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); 716 void bdrv_unregister_buf(BlockDriverState *bs, void *host); 717 718 /** 719 * 720 * bdrv_co_copy_range: 721 * 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. 725 * 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. 730 * 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. 744 * 745 * Returns: 0 if succeeded; negative error code if failed. 746 **/ 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 752