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 #define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1) 147 148 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \ 149 INT_MAX >> BDRV_SECTOR_BITS) 150 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) 151 152 /* 153 * Allocation status flags for bdrv_block_status() and friends. 154 * 155 * Public flags: 156 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer 157 * BDRV_BLOCK_ZERO: offset reads as zero 158 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data 159 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this 160 * layer rather than any backing, set by block layer 161 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this 162 * layer, set by block layer 163 * 164 * Internal flags: 165 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request 166 * that the block layer recompute the answer from the returned 167 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID. 168 * BDRV_BLOCK_RECURSE: request that the block layer will recursively search for 169 * zeroes in file child of current block node inside 170 * returned region. Only valid together with both 171 * BDRV_BLOCK_DATA and BDRV_BLOCK_OFFSET_VALID. Should not 172 * appear with BDRV_BLOCK_ZERO. 173 * 174 * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the 175 * host offset within the returned BDS that is allocated for the 176 * corresponding raw guest data. However, whether that offset 177 * actually contains data also depends on BDRV_BLOCK_DATA, as follows: 178 * 179 * DATA ZERO OFFSET_VALID 180 * t t t sectors read as zero, returned file is zero at offset 181 * t f t sectors read as valid from file at offset 182 * f t t sectors preallocated, read as zero, returned file not 183 * necessarily zero at offset 184 * f f t sectors preallocated but read from backing_hd, 185 * returned file contains garbage at offset 186 * t t f sectors preallocated, read as zero, unknown offset 187 * t f f sectors read from unknown file or offset 188 * f t f not allocated or unknown offset, read as zero 189 * f f f not allocated or unknown offset, read from backing_hd 190 */ 191 #define BDRV_BLOCK_DATA 0x01 192 #define BDRV_BLOCK_ZERO 0x02 193 #define BDRV_BLOCK_OFFSET_VALID 0x04 194 #define BDRV_BLOCK_RAW 0x08 195 #define BDRV_BLOCK_ALLOCATED 0x10 196 #define BDRV_BLOCK_EOF 0x20 197 #define BDRV_BLOCK_RECURSE 0x40 198 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK 199 200 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 201 202 typedef struct BDRVReopenState { 203 BlockDriverState *bs; 204 int flags; 205 BlockdevDetectZeroesOptions detect_zeroes; 206 bool backing_missing; 207 bool replace_backing_bs; /* new_backing_bs is ignored if this is false */ 208 BlockDriverState *new_backing_bs; /* If NULL then detach the current bs */ 209 uint64_t perm, shared_perm; 210 QDict *options; 211 QDict *explicit_options; 212 void *opaque; 213 } BDRVReopenState; 214 215 /* 216 * Block operation types 217 */ 218 typedef enum BlockOpType { 219 BLOCK_OP_TYPE_BACKUP_SOURCE, 220 BLOCK_OP_TYPE_BACKUP_TARGET, 221 BLOCK_OP_TYPE_CHANGE, 222 BLOCK_OP_TYPE_COMMIT_SOURCE, 223 BLOCK_OP_TYPE_COMMIT_TARGET, 224 BLOCK_OP_TYPE_DATAPLANE, 225 BLOCK_OP_TYPE_DRIVE_DEL, 226 BLOCK_OP_TYPE_EJECT, 227 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, 228 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, 229 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, 230 BLOCK_OP_TYPE_MIRROR_SOURCE, 231 BLOCK_OP_TYPE_MIRROR_TARGET, 232 BLOCK_OP_TYPE_RESIZE, 233 BLOCK_OP_TYPE_STREAM, 234 BLOCK_OP_TYPE_REPLACE, 235 BLOCK_OP_TYPE_MAX, 236 } BlockOpType; 237 238 /* Block node permission constants */ 239 enum { 240 /** 241 * A user that has the "permission" of consistent reads is guaranteed that 242 * their view of the contents of the block device is complete and 243 * self-consistent, representing the contents of a disk at a specific 244 * point. 245 * 246 * For most block devices (including their backing files) this is true, but 247 * the property cannot be maintained in a few situations like for 248 * intermediate nodes of a commit block job. 249 */ 250 BLK_PERM_CONSISTENT_READ = 0x01, 251 252 /** This permission is required to change the visible disk contents. */ 253 BLK_PERM_WRITE = 0x02, 254 255 /** 256 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and 257 * required for writes to the block node when the caller promises that 258 * the visible disk content doesn't change. 259 * 260 * As the BLK_PERM_WRITE permission is strictly stronger, either is 261 * sufficient to perform an unchanging write. 262 */ 263 BLK_PERM_WRITE_UNCHANGED = 0x04, 264 265 /** This permission is required to change the size of a block node. */ 266 BLK_PERM_RESIZE = 0x08, 267 268 /** 269 * This permission is required to change the node that this BdrvChild 270 * points to. 271 */ 272 BLK_PERM_GRAPH_MOD = 0x10, 273 274 BLK_PERM_ALL = 0x1f, 275 276 DEFAULT_PERM_PASSTHROUGH = BLK_PERM_CONSISTENT_READ 277 | BLK_PERM_WRITE 278 | BLK_PERM_WRITE_UNCHANGED 279 | BLK_PERM_RESIZE, 280 281 DEFAULT_PERM_UNCHANGED = BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH, 282 }; 283 284 char *bdrv_perm_names(uint64_t perm); 285 286 /* disk I/O throttling */ 287 void bdrv_init(void); 288 void bdrv_init_with_whitelist(void); 289 bool bdrv_uses_whitelist(void); 290 int bdrv_is_whitelisted(BlockDriver *drv, bool read_only); 291 BlockDriver *bdrv_find_protocol(const char *filename, 292 bool allow_protocol_prefix, 293 Error **errp); 294 BlockDriver *bdrv_find_format(const char *format_name); 295 int bdrv_create(BlockDriver *drv, const char* filename, 296 QemuOpts *opts, Error **errp); 297 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 298 BlockDriverState *bdrv_new(void); 299 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 300 Error **errp); 301 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 302 Error **errp); 303 304 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough); 305 int bdrv_parse_discard_flags(const char *mode, int *flags); 306 BdrvChild *bdrv_open_child(const char *filename, 307 QDict *options, const char *bdref_key, 308 BlockDriverState* parent, 309 const BdrvChildRole *child_role, 310 bool allow_none, Error **errp); 311 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp); 312 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 313 Error **errp); 314 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 315 const char *bdref_key, Error **errp); 316 BlockDriverState *bdrv_open(const char *filename, const char *reference, 317 QDict *options, int flags, Error **errp); 318 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 319 int flags, Error **errp); 320 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 321 BlockDriverState *bs, QDict *options, 322 bool keep_old_opts); 323 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp); 324 int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, 325 Error **errp); 326 int bdrv_reopen_prepare(BDRVReopenState *reopen_state, 327 BlockReopenQueue *queue, Error **errp); 328 void bdrv_reopen_commit(BDRVReopenState *reopen_state); 329 void bdrv_reopen_abort(BDRVReopenState *reopen_state); 330 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, 331 int bytes, BdrvRequestFlags flags); 332 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); 333 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes); 334 int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 335 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes); 336 int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 337 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, 338 const void *buf, int count); 339 /* 340 * Efficiently zero a region of the disk image. Note that this is a regular 341 * I/O request like read or write and should have a reasonable size. This 342 * function is not suitable for zeroing the entire image in a single request 343 * because it may allocate memory for the entire region. 344 */ 345 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, 346 int bytes, BdrvRequestFlags flags); 347 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 348 const char *backing_file); 349 void bdrv_refresh_filename(BlockDriverState *bs); 350 351 int coroutine_fn bdrv_co_truncate(BdrvChild *child, int64_t offset, 352 PreallocMode prealloc, Error **errp); 353 int bdrv_truncate(BdrvChild *child, int64_t offset, PreallocMode prealloc, 354 Error **errp); 355 356 int64_t bdrv_nb_sectors(BlockDriverState *bs); 357 int64_t bdrv_getlength(BlockDriverState *bs); 358 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); 359 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, 360 BlockDriverState *in_bs, Error **errp); 361 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr); 362 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp); 363 int bdrv_commit(BlockDriverState *bs); 364 int bdrv_change_backing_file(BlockDriverState *bs, 365 const char *backing_file, const char *backing_fmt); 366 void bdrv_register(BlockDriver *bdrv); 367 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 368 const char *backing_file_str); 369 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 370 BlockDriverState *bs); 371 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 372 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base, 373 Error **errp); 374 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base, 375 Error **errp); 376 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base); 377 378 379 typedef struct BdrvCheckResult { 380 int corruptions; 381 int leaks; 382 int check_errors; 383 int corruptions_fixed; 384 int leaks_fixed; 385 int64_t image_end_offset; 386 BlockFragInfo bfi; 387 } BdrvCheckResult; 388 389 typedef enum { 390 BDRV_FIX_LEAKS = 1, 391 BDRV_FIX_ERRORS = 2, 392 } BdrvCheckMode; 393 394 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); 395 396 /* The units of offset and total_work_size may be chosen arbitrarily by the 397 * block driver; total_work_size may change during the course of the amendment 398 * operation */ 399 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 400 int64_t total_work_size, void *opaque); 401 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 402 BlockDriverAmendStatusCB *status_cb, void *cb_opaque, 403 Error **errp); 404 405 /* external snapshots */ 406 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs, 407 BlockDriverState *candidate); 408 bool bdrv_is_first_non_filter(BlockDriverState *candidate); 409 410 /* check if a named node can be replaced when doing drive-mirror */ 411 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 412 const char *node_name, Error **errp); 413 414 /* async block I/O */ 415 void bdrv_aio_cancel(BlockAIOCB *acb); 416 void bdrv_aio_cancel_async(BlockAIOCB *acb); 417 418 /* sg packet commands */ 419 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 420 421 /* Invalidate any cached metadata used by image formats */ 422 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp); 423 void bdrv_invalidate_cache_all(Error **errp); 424 int bdrv_inactivate_all(void); 425 426 /* Ensure contents are flushed to disk. */ 427 int bdrv_flush(BlockDriverState *bs); 428 int coroutine_fn bdrv_co_flush(BlockDriverState *bs); 429 int bdrv_flush_all(void); 430 void bdrv_close_all(void); 431 void bdrv_drain(BlockDriverState *bs); 432 void coroutine_fn bdrv_co_drain(BlockDriverState *bs); 433 void bdrv_drain_all_begin(void); 434 void bdrv_drain_all_end(void); 435 void bdrv_drain_all(void); 436 437 #define BDRV_POLL_WHILE(bs, cond) ({ \ 438 BlockDriverState *bs_ = (bs); \ 439 AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \ 440 cond); }) 441 442 int bdrv_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); 443 int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); 444 int bdrv_has_zero_init_1(BlockDriverState *bs); 445 int bdrv_has_zero_init(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 void bdrv_round_to_clusters(BlockDriverState *bs, 506 int64_t offset, int64_t bytes, 507 int64_t *cluster_offset, 508 int64_t *cluster_bytes); 509 510 void bdrv_get_backing_filename(BlockDriverState *bs, 511 char *filename, int filename_size); 512 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); 513 char *bdrv_get_full_backing_filename_from_filename(const char *backed, 514 const char *backing, 515 Error **errp); 516 char *bdrv_dirname(BlockDriverState *bs, Error **errp); 517 518 int path_has_protocol(const char *path); 519 int path_is_absolute(const char *path); 520 char *path_combine(const char *base_path, const char *filename); 521 522 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 523 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 524 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 525 int64_t pos, int size); 526 527 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 528 int64_t pos, int size); 529 530 void bdrv_img_create(const char *filename, const char *fmt, 531 const char *base_filename, const char *base_fmt, 532 char *options, uint64_t img_size, int flags, 533 bool quiet, Error **errp); 534 535 /* Returns the alignment in bytes that is required so that no bounce buffer 536 * is required throughout the stack */ 537 size_t bdrv_min_mem_align(BlockDriverState *bs); 538 /* Returns optimal alignment in bytes for bounce buffer */ 539 size_t bdrv_opt_mem_align(BlockDriverState *bs); 540 void *qemu_blockalign(BlockDriverState *bs, size_t size); 541 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 542 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 543 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 544 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 545 546 void bdrv_enable_copy_on_read(BlockDriverState *bs); 547 void bdrv_disable_copy_on_read(BlockDriverState *bs); 548 549 void bdrv_ref(BlockDriverState *bs); 550 void bdrv_unref(BlockDriverState *bs); 551 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 552 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 553 BlockDriverState *child_bs, 554 const char *child_name, 555 const BdrvChildRole *child_role, 556 Error **errp); 557 558 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 559 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 560 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 561 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 562 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 563 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 564 565 #define BLKDBG_EVENT(child, evt) \ 566 do { \ 567 if (child) { \ 568 bdrv_debug_event(child->bs, evt); \ 569 } \ 570 } while (0) 571 572 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 573 574 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 575 const char *tag); 576 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 577 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 578 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 579 580 /** 581 * bdrv_get_aio_context: 582 * 583 * Returns: the currently bound #AioContext 584 */ 585 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 586 587 /** 588 * Transfer control to @co in the aio context of @bs 589 */ 590 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 591 592 void bdrv_set_aio_context_ignore(BlockDriverState *bs, 593 AioContext *new_context, GSList **ignore); 594 int bdrv_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 595 Error **errp); 596 int bdrv_child_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 597 BdrvChild *ignore_child, Error **errp); 598 bool bdrv_child_can_set_aio_context(BdrvChild *c, AioContext *ctx, 599 GSList **ignore, Error **errp); 600 bool bdrv_can_set_aio_context(BlockDriverState *bs, AioContext *ctx, 601 GSList **ignore, Error **errp); 602 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 603 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 604 605 void bdrv_io_plug(BlockDriverState *bs); 606 void bdrv_io_unplug(BlockDriverState *bs); 607 608 /** 609 * bdrv_parent_drained_begin_single: 610 * 611 * Begin a quiesced section for the parent of @c. If @poll is true, wait for 612 * any pending activity to cease. 613 */ 614 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); 615 616 /** 617 * bdrv_parent_drained_end_single: 618 * 619 * End a quiesced section for the parent of @c. 620 * 621 * This polls @bs's AioContext until all scheduled sub-drained_ends 622 * have settled, which may result in graph changes. 623 */ 624 void bdrv_parent_drained_end_single(BdrvChild *c); 625 626 /** 627 * bdrv_drain_poll: 628 * 629 * Poll for pending requests in @bs, its parents (except for @ignore_parent), 630 * and if @recursive is true its children as well (used for subtree drain). 631 * 632 * If @ignore_bds_parents is true, parents that are BlockDriverStates must 633 * ignore the drain request because they will be drained separately (used for 634 * drain_all). 635 * 636 * This is part of bdrv_drained_begin. 637 */ 638 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, 639 BdrvChild *ignore_parent, bool ignore_bds_parents); 640 641 /** 642 * bdrv_drained_begin: 643 * 644 * Begin a quiesced section for exclusive access to the BDS, by disabling 645 * external request sources including NBD server and device model. Note that 646 * this doesn't block timers or coroutines from submitting more requests, which 647 * means block_job_pause is still necessary. 648 * 649 * This function can be recursive. 650 */ 651 void bdrv_drained_begin(BlockDriverState *bs); 652 653 /** 654 * bdrv_do_drained_begin_quiesce: 655 * 656 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already 657 * running requests to complete. 658 */ 659 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, 660 BdrvChild *parent, bool ignore_bds_parents); 661 662 /** 663 * Like bdrv_drained_begin, but recursively begins a quiesced section for 664 * exclusive access to all child nodes as well. 665 */ 666 void bdrv_subtree_drained_begin(BlockDriverState *bs); 667 668 /** 669 * bdrv_drained_end: 670 * 671 * End a quiescent section started by bdrv_drained_begin(). 672 * 673 * This polls @bs's AioContext until all scheduled sub-drained_ends 674 * have settled. On one hand, that may result in graph changes. On 675 * the other, this requires that the caller either runs in the main 676 * loop; or that all involved nodes (@bs and all of its parents) are 677 * in the caller's AioContext. 678 */ 679 void bdrv_drained_end(BlockDriverState *bs); 680 681 /** 682 * bdrv_drained_end_no_poll: 683 * 684 * Same as bdrv_drained_end(), but do not poll for the subgraph to 685 * actually become unquiesced. Therefore, no graph changes will occur 686 * with this function. 687 * 688 * *drained_end_counter is incremented for every background operation 689 * that is scheduled, and will be decremented for every operation once 690 * it settles. The caller must poll until it reaches 0. The counter 691 * should be accessed using atomic operations only. 692 */ 693 void bdrv_drained_end_no_poll(BlockDriverState *bs, int *drained_end_counter); 694 695 /** 696 * End a quiescent section started by bdrv_subtree_drained_begin(). 697 */ 698 void bdrv_subtree_drained_end(BlockDriverState *bs); 699 700 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 701 Error **errp); 702 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 703 704 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, 705 uint32_t granularity, Error **errp); 706 /** 707 * 708 * bdrv_register_buf/bdrv_unregister_buf: 709 * 710 * Register/unregister a buffer for I/O. For example, VFIO drivers are 711 * interested to know the memory areas that would later be used for I/O, so 712 * that they can prepare IOMMU mapping etc., to get better performance. 713 */ 714 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); 715 void bdrv_unregister_buf(BlockDriverState *bs, void *host); 716 717 /** 718 * 719 * bdrv_co_copy_range: 720 * 721 * Do offloaded copy between two children. If the operation is not implemented 722 * by the driver, or if the backend storage doesn't support it, a negative 723 * error code will be returned. 724 * 725 * Note: block layer doesn't emulate or fallback to a bounce buffer approach 726 * because usually the caller shouldn't attempt offloaded copy any more (e.g. 727 * calling copy_file_range(2)) after the first error, thus it should fall back 728 * to a read+write path in the caller level. 729 * 730 * @src: Source child to copy data from 731 * @src_offset: offset in @src image to read data 732 * @dst: Destination child to copy data to 733 * @dst_offset: offset in @dst image to write data 734 * @bytes: number of bytes to copy 735 * @flags: request flags. Supported flags: 736 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero 737 * write on @dst as if bdrv_co_pwrite_zeroes is 738 * called. Used to simplify caller code, or 739 * during BlockDriver.bdrv_co_copy_range_from() 740 * recursion. 741 * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping 742 * requests currently in flight. 743 * 744 * Returns: 0 if succeeded; negative error code if failed. 745 **/ 746 int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset, 747 BdrvChild *dst, uint64_t dst_offset, 748 uint64_t bytes, BdrvRequestFlags read_flags, 749 BdrvRequestFlags write_flags); 750 #endif 751