1 #ifndef BLOCK_H 2 #define BLOCK_H 3 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" 13 14 /* block.c */ 15 typedef struct BlockDriver BlockDriver; 16 typedef struct BdrvChild BdrvChild; 17 typedef struct BdrvChildRole BdrvChildRole; 18 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; 25 /* 26 * True if unallocated blocks read back as zeroes. This is equivalent 27 * to the LBPRZ flag in the SCSI logical block provisioning page. 28 */ 29 bool unallocated_blocks_are_zero; 30 /* 31 * True if this block driver only supports compressed writes 32 */ 33 bool needs_compressed_writes; 34 } BlockDriverInfo; 35 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; 42 43 typedef enum { 44 BDRV_REQ_COPY_ON_READ = 0x1, 45 BDRV_REQ_ZERO_WRITE = 0x2, 46 47 /* 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. 52 */ 53 BDRV_REQ_MAY_UNMAP = 0x4, 54 55 /* 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. 58 * 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). 65 */ 66 BDRV_REQ_NO_SERIALISING = 0x8, 67 BDRV_REQ_FUA = 0x10, 68 BDRV_REQ_WRITE_COMPRESSED = 0x20, 69 70 /* Signifies that this write request will not change the visible disk 71 * content. */ 72 BDRV_REQ_WRITE_UNCHANGED = 0x40, 73 74 /* 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. 79 * 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. 83 */ 84 BDRV_REQ_SERIALISING = 0x80, 85 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, 90 91 /* Mask of valid flags */ 92 BDRV_REQ_MASK = 0x1ff, 93 } BdrvRequestFlags; 94 95 typedef struct BlockSizes { 96 uint32_t phys; 97 uint32_t log; 98 } BlockSizes; 99 100 typedef struct HDGeometry { 101 uint32_t heads; 102 uint32_t sectors; 103 uint32_t cylinders; 104 } HDGeometry; 105 106 #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 */ 124 125 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 126 127 128 /* Option names of options parsed by the block layer */ 129 130 #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" 137 138 139 #define BDRV_SECTOR_BITS 9 140 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS) 141 #define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1) 142 143 #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) 146 147 /* 148 * Allocation status flags for bdrv_block_status() and friends. 149 * 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 158 * 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. 163 * 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: 168 * 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 180 */ 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 188 189 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 190 191 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; 203 204 /* 205 * Block operation types 206 */ 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; 226 227 /* Block node permission constants */ 228 enum { 229 /** 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. 234 * 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. 238 */ 239 BLK_PERM_CONSISTENT_READ = 0x01, 240 241 /** This permission is required to change the visible disk contents. */ 242 BLK_PERM_WRITE = 0x02, 243 244 /** 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. 248 * 249 * As the BLK_PERM_WRITE permission is strictly stronger, either is 250 * sufficient to perform an unchanging write. 251 */ 252 BLK_PERM_WRITE_UNCHANGED = 0x04, 253 254 /** This permission is required to change the size of a block node. */ 255 BLK_PERM_RESIZE = 0x08, 256 257 /** 258 * This permission is required to change the node that this BdrvChild 259 * points to. 260 */ 261 BLK_PERM_GRAPH_MOD = 0x10, 262 263 BLK_PERM_ALL = 0x1f, 264 265 DEFAULT_PERM_PASSTHROUGH = BLK_PERM_CONSISTENT_READ 266 | BLK_PERM_WRITE 267 | BLK_PERM_WRITE_UNCHANGED 268 | BLK_PERM_RESIZE, 269 270 DEFAULT_PERM_UNCHANGED = BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH, 271 }; 272 273 char *bdrv_perm_names(uint64_t perm); 274 275 /* 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); 292 293 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_pwrite_zeroes(BdrvChild *child, int64_t offset, 320 int bytes, BdrvRequestFlags flags); 321 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); 322 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes); 323 int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 324 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes); 325 int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 326 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, 327 const void *buf, int count); 328 /* 329 * Efficiently zero a region of the disk image. Note that this is a regular 330 * I/O request like read or write and should have a reasonable size. This 331 * function is not suitable for zeroing the entire image in a single request 332 * because it may allocate memory for the entire region. 333 */ 334 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, 335 int bytes, BdrvRequestFlags flags); 336 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 337 const char *backing_file); 338 void bdrv_refresh_filename(BlockDriverState *bs); 339 340 int coroutine_fn bdrv_co_truncate(BdrvChild *child, int64_t offset, 341 PreallocMode prealloc, Error **errp); 342 int bdrv_truncate(BdrvChild *child, int64_t offset, PreallocMode prealloc, 343 Error **errp); 344 345 int64_t bdrv_nb_sectors(BlockDriverState *bs); 346 int64_t bdrv_getlength(BlockDriverState *bs); 347 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); 348 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, 349 BlockDriverState *in_bs, Error **errp); 350 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr); 351 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp); 352 int bdrv_commit(BlockDriverState *bs); 353 int bdrv_change_backing_file(BlockDriverState *bs, 354 const char *backing_file, const char *backing_fmt); 355 void bdrv_register(BlockDriver *bdrv); 356 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 357 const char *backing_file_str); 358 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 359 BlockDriverState *bs); 360 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 361 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base, 362 Error **errp); 363 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base, 364 Error **errp); 365 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base); 366 367 368 typedef struct BdrvCheckResult { 369 int corruptions; 370 int leaks; 371 int check_errors; 372 int corruptions_fixed; 373 int leaks_fixed; 374 int64_t image_end_offset; 375 BlockFragInfo bfi; 376 } BdrvCheckResult; 377 378 typedef enum { 379 BDRV_FIX_LEAKS = 1, 380 BDRV_FIX_ERRORS = 2, 381 } BdrvCheckMode; 382 383 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); 384 385 /* The units of offset and total_work_size may be chosen arbitrarily by the 386 * block driver; total_work_size may change during the course of the amendment 387 * operation */ 388 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 389 int64_t total_work_size, void *opaque); 390 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 391 BlockDriverAmendStatusCB *status_cb, void *cb_opaque, 392 Error **errp); 393 394 /* external snapshots */ 395 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs, 396 BlockDriverState *candidate); 397 bool bdrv_is_first_non_filter(BlockDriverState *candidate); 398 399 /* check if a named node can be replaced when doing drive-mirror */ 400 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 401 const char *node_name, Error **errp); 402 403 /* async block I/O */ 404 void bdrv_aio_cancel(BlockAIOCB *acb); 405 void bdrv_aio_cancel_async(BlockAIOCB *acb); 406 407 /* sg packet commands */ 408 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 409 410 /* Invalidate any cached metadata used by image formats */ 411 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp); 412 void bdrv_invalidate_cache_all(Error **errp); 413 int bdrv_inactivate_all(void); 414 415 /* Ensure contents are flushed to disk. */ 416 int bdrv_flush(BlockDriverState *bs); 417 int coroutine_fn bdrv_co_flush(BlockDriverState *bs); 418 int bdrv_flush_all(void); 419 void bdrv_close_all(void); 420 void bdrv_drain(BlockDriverState *bs); 421 void coroutine_fn bdrv_co_drain(BlockDriverState *bs); 422 void bdrv_drain_all_begin(void); 423 void bdrv_drain_all_end(void); 424 void bdrv_drain_all(void); 425 426 #define BDRV_POLL_WHILE(bs, cond) ({ \ 427 BlockDriverState *bs_ = (bs); \ 428 AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \ 429 cond); }) 430 431 int bdrv_pdiscard(BdrvChild *child, int64_t offset, int bytes); 432 int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int bytes); 433 int bdrv_has_zero_init_1(BlockDriverState *bs); 434 int bdrv_has_zero_init(BlockDriverState *bs); 435 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs); 436 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); 437 int bdrv_block_status(BlockDriverState *bs, int64_t offset, 438 int64_t bytes, int64_t *pnum, int64_t *map, 439 BlockDriverState **file); 440 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, 441 int64_t offset, int64_t bytes, int64_t *pnum, 442 int64_t *map, BlockDriverState **file); 443 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, 444 int64_t *pnum); 445 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, 446 int64_t offset, int64_t bytes, int64_t *pnum); 447 448 bool bdrv_is_read_only(BlockDriverState *bs); 449 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, 450 bool ignore_allow_rdw, Error **errp); 451 int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, 452 Error **errp); 453 bool bdrv_is_writable(BlockDriverState *bs); 454 bool bdrv_is_sg(BlockDriverState *bs); 455 bool bdrv_is_inserted(BlockDriverState *bs); 456 void bdrv_lock_medium(BlockDriverState *bs, bool locked); 457 void bdrv_eject(BlockDriverState *bs, bool eject_flag); 458 const char *bdrv_get_format_name(BlockDriverState *bs); 459 BlockDriverState *bdrv_find_node(const char *node_name); 460 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp); 461 XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp); 462 BlockDriverState *bdrv_lookup_bs(const char *device, 463 const char *node_name, 464 Error **errp); 465 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 466 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 467 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs); 468 469 typedef struct BdrvNextIterator { 470 enum { 471 BDRV_NEXT_BACKEND_ROOTS, 472 BDRV_NEXT_MONITOR_OWNED, 473 } phase; 474 BlockBackend *blk; 475 BlockDriverState *bs; 476 } BdrvNextIterator; 477 478 BlockDriverState *bdrv_first(BdrvNextIterator *it); 479 BlockDriverState *bdrv_next(BdrvNextIterator *it); 480 void bdrv_next_cleanup(BdrvNextIterator *it); 481 482 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 483 bool bdrv_is_encrypted(BlockDriverState *bs); 484 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 485 void *opaque, bool read_only); 486 const char *bdrv_get_node_name(const BlockDriverState *bs); 487 const char *bdrv_get_device_name(const BlockDriverState *bs); 488 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs); 489 int bdrv_get_flags(BlockDriverState *bs); 490 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); 491 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs, 492 Error **errp); 493 void bdrv_round_to_clusters(BlockDriverState *bs, 494 int64_t offset, int64_t bytes, 495 int64_t *cluster_offset, 496 int64_t *cluster_bytes); 497 498 void bdrv_get_backing_filename(BlockDriverState *bs, 499 char *filename, int filename_size); 500 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); 501 char *bdrv_get_full_backing_filename_from_filename(const char *backed, 502 const char *backing, 503 Error **errp); 504 char *bdrv_dirname(BlockDriverState *bs, Error **errp); 505 506 int path_has_protocol(const char *path); 507 int path_is_absolute(const char *path); 508 char *path_combine(const char *base_path, const char *filename); 509 510 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 511 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 512 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 513 int64_t pos, int size); 514 515 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 516 int64_t pos, int size); 517 518 void bdrv_img_create(const char *filename, const char *fmt, 519 const char *base_filename, const char *base_fmt, 520 char *options, uint64_t img_size, int flags, 521 bool quiet, Error **errp); 522 523 /* Returns the alignment in bytes that is required so that no bounce buffer 524 * is required throughout the stack */ 525 size_t bdrv_min_mem_align(BlockDriverState *bs); 526 /* Returns optimal alignment in bytes for bounce buffer */ 527 size_t bdrv_opt_mem_align(BlockDriverState *bs); 528 void *qemu_blockalign(BlockDriverState *bs, size_t size); 529 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 530 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 531 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 532 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 533 534 void bdrv_enable_copy_on_read(BlockDriverState *bs); 535 void bdrv_disable_copy_on_read(BlockDriverState *bs); 536 537 void bdrv_ref(BlockDriverState *bs); 538 void bdrv_unref(BlockDriverState *bs); 539 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 540 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 541 BlockDriverState *child_bs, 542 const char *child_name, 543 const BdrvChildRole *child_role, 544 Error **errp); 545 546 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 547 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 548 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 549 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 550 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 551 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 552 553 #define BLKDBG_EVENT(child, evt) \ 554 do { \ 555 if (child) { \ 556 bdrv_debug_event(child->bs, evt); \ 557 } \ 558 } while (0) 559 560 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 561 562 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 563 const char *tag); 564 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 565 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 566 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 567 568 /** 569 * bdrv_get_aio_context: 570 * 571 * Returns: the currently bound #AioContext 572 */ 573 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 574 575 /** 576 * Transfer control to @co in the aio context of @bs 577 */ 578 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 579 580 /** 581 * bdrv_set_aio_context: 582 * 583 * Changes the #AioContext used for fd handlers, timers, and BHs by this 584 * BlockDriverState and all its children. 585 * 586 * This function must be called with iothread lock held. 587 */ 588 void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context); 589 void bdrv_set_aio_context_ignore(BlockDriverState *bs, 590 AioContext *new_context, GSList **ignore); 591 int bdrv_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 592 Error **errp); 593 int bdrv_child_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 594 BdrvChild *ignore_child, Error **errp); 595 bool bdrv_child_can_set_aio_context(BdrvChild *c, AioContext *ctx, 596 GSList **ignore, Error **errp); 597 bool bdrv_can_set_aio_context(BlockDriverState *bs, AioContext *ctx, 598 GSList **ignore, Error **errp); 599 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 600 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 601 602 void bdrv_io_plug(BlockDriverState *bs); 603 void bdrv_io_unplug(BlockDriverState *bs); 604 605 /** 606 * bdrv_parent_drained_begin: 607 * 608 * Begin a quiesced section of all users of @bs. This is part of 609 * bdrv_drained_begin. 610 */ 611 void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore, 612 bool ignore_bds_parents); 613 614 /** 615 * bdrv_parent_drained_begin_single: 616 * 617 * Begin a quiesced section for the parent of @c. If @poll is true, wait for 618 * any pending activity to cease. 619 */ 620 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); 621 622 /** 623 * bdrv_parent_drained_end: 624 * 625 * End a quiesced section of all users of @bs. This is part of 626 * bdrv_drained_end. 627 */ 628 void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore, 629 bool ignore_bds_parents); 630 631 /** 632 * bdrv_drain_poll: 633 * 634 * Poll for pending requests in @bs, its parents (except for @ignore_parent), 635 * and if @recursive is true its children as well (used for subtree drain). 636 * 637 * If @ignore_bds_parents is true, parents that are BlockDriverStates must 638 * ignore the drain request because they will be drained separately (used for 639 * drain_all). 640 * 641 * This is part of bdrv_drained_begin. 642 */ 643 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, 644 BdrvChild *ignore_parent, bool ignore_bds_parents); 645 646 /** 647 * bdrv_drained_begin: 648 * 649 * Begin a quiesced section for exclusive access to the BDS, by disabling 650 * external request sources including NBD server and device model. Note that 651 * this doesn't block timers or coroutines from submitting more requests, which 652 * means block_job_pause is still necessary. 653 * 654 * This function can be recursive. 655 */ 656 void bdrv_drained_begin(BlockDriverState *bs); 657 658 /** 659 * bdrv_do_drained_begin_quiesce: 660 * 661 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already 662 * running requests to complete. 663 */ 664 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, 665 BdrvChild *parent, bool ignore_bds_parents); 666 667 /** 668 * Like bdrv_drained_begin, but recursively begins a quiesced section for 669 * exclusive access to all child nodes as well. 670 */ 671 void bdrv_subtree_drained_begin(BlockDriverState *bs); 672 673 /** 674 * bdrv_drained_end: 675 * 676 * End a quiescent section started by bdrv_drained_begin(). 677 */ 678 void bdrv_drained_end(BlockDriverState *bs); 679 680 /** 681 * End a quiescent section started by bdrv_subtree_drained_begin(). 682 */ 683 void bdrv_subtree_drained_end(BlockDriverState *bs); 684 685 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 686 Error **errp); 687 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 688 689 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, 690 uint32_t granularity, Error **errp); 691 /** 692 * 693 * bdrv_register_buf/bdrv_unregister_buf: 694 * 695 * Register/unregister a buffer for I/O. For example, VFIO drivers are 696 * interested to know the memory areas that would later be used for I/O, so 697 * that they can prepare IOMMU mapping etc., to get better performance. 698 */ 699 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); 700 void bdrv_unregister_buf(BlockDriverState *bs, void *host); 701 702 /** 703 * 704 * bdrv_co_copy_range: 705 * 706 * Do offloaded copy between two children. If the operation is not implemented 707 * by the driver, or if the backend storage doesn't support it, a negative 708 * error code will be returned. 709 * 710 * Note: block layer doesn't emulate or fallback to a bounce buffer approach 711 * because usually the caller shouldn't attempt offloaded copy any more (e.g. 712 * calling copy_file_range(2)) after the first error, thus it should fall back 713 * to a read+write path in the caller level. 714 * 715 * @src: Source child to copy data from 716 * @src_offset: offset in @src image to read data 717 * @dst: Destination child to copy data to 718 * @dst_offset: offset in @dst image to write data 719 * @bytes: number of bytes to copy 720 * @flags: request flags. Supported flags: 721 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero 722 * write on @dst as if bdrv_co_pwrite_zeroes is 723 * called. Used to simplify caller code, or 724 * during BlockDriver.bdrv_co_copy_range_from() 725 * recursion. 726 * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping 727 * requests currently in flight. 728 * 729 * Returns: 0 if succeeded; negative error code if failed. 730 **/ 731 int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset, 732 BdrvChild *dst, uint64_t dst_offset, 733 uint64_t bytes, BdrvRequestFlags read_flags, 734 BdrvRequestFlags write_flags); 735 #endif 736