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 BDRV_REQ_FUA = 0x10, 55 BDRV_REQ_WRITE_COMPRESSED = 0x20, 56 57 /* Signifies that this write request will not change the visible disk 58 * content. */ 59 BDRV_REQ_WRITE_UNCHANGED = 0x40, 60 61 /* 62 * BDRV_REQ_SERIALISING forces request serialisation for writes. 63 * It is used to ensure that writes to the backing file of a backup process 64 * target cannot race with a read of the backup target that defers to the 65 * backing file. 66 * 67 * Note, that BDRV_REQ_SERIALISING is _not_ opposite in meaning to 68 * BDRV_REQ_NO_SERIALISING. A more descriptive name for the latter might be 69 * _DO_NOT_WAIT_FOR_SERIALISING, except that is too long. 70 */ 71 BDRV_REQ_SERIALISING = 0x80, 72 73 /* Execute the request only if the operation can be offloaded or otherwise 74 * be executed efficiently, but return an error instead of using a slow 75 * fallback. */ 76 BDRV_REQ_NO_FALLBACK = 0x100, 77 78 /* 79 * BDRV_REQ_PREFETCH may be used only together with BDRV_REQ_COPY_ON_READ 80 * on read request and means that caller doesn't really need data to be 81 * written to qiov parameter which may be NULL. 82 */ 83 BDRV_REQ_PREFETCH = 0x200, 84 /* Mask of valid flags */ 85 BDRV_REQ_MASK = 0x3ff, 86 } BdrvRequestFlags; 87 88 typedef struct BlockSizes { 89 uint32_t phys; 90 uint32_t log; 91 } BlockSizes; 92 93 typedef struct HDGeometry { 94 uint32_t heads; 95 uint32_t sectors; 96 uint32_t cylinders; 97 } HDGeometry; 98 99 #define BDRV_O_RDWR 0x0002 100 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */ 101 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */ 102 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */ 103 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ 104 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */ 105 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */ 106 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */ 107 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */ 108 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */ 109 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */ 110 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */ 111 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */ 112 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given: 113 select an appropriate protocol driver, 114 ignoring the format layer */ 115 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */ 116 #define BDRV_O_AUTO_RDONLY 0x20000 /* degrade to read-only if opening read-write fails */ 117 #define BDRV_O_IO_URING 0x40000 /* use io_uring instead of the thread pool */ 118 119 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 120 121 122 /* Option names of options parsed by the block layer */ 123 124 #define BDRV_OPT_CACHE_WB "cache.writeback" 125 #define BDRV_OPT_CACHE_DIRECT "cache.direct" 126 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush" 127 #define BDRV_OPT_READ_ONLY "read-only" 128 #define BDRV_OPT_AUTO_READ_ONLY "auto-read-only" 129 #define BDRV_OPT_DISCARD "discard" 130 #define BDRV_OPT_FORCE_SHARE "force-share" 131 132 133 #define BDRV_SECTOR_BITS 9 134 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS) 135 136 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \ 137 INT_MAX >> BDRV_SECTOR_BITS) 138 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) 139 140 /* 141 * Allocation status flags for bdrv_block_status() and friends. 142 * 143 * Public flags: 144 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer 145 * BDRV_BLOCK_ZERO: offset reads as zero 146 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data 147 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this 148 * layer rather than any backing, set by block layer 149 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this 150 * layer, set by block layer 151 * 152 * Internal flags: 153 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request 154 * that the block layer recompute the answer from the returned 155 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID. 156 * BDRV_BLOCK_RECURSE: request that the block layer will recursively search for 157 * zeroes in file child of current block node inside 158 * returned region. Only valid together with both 159 * BDRV_BLOCK_DATA and BDRV_BLOCK_OFFSET_VALID. Should not 160 * appear with BDRV_BLOCK_ZERO. 161 * 162 * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the 163 * host offset within the returned BDS that is allocated for the 164 * corresponding raw guest data. However, whether that offset 165 * actually contains data also depends on BDRV_BLOCK_DATA, as follows: 166 * 167 * DATA ZERO OFFSET_VALID 168 * t t t sectors read as zero, returned file is zero at offset 169 * t f t sectors read as valid from file at offset 170 * f t t sectors preallocated, read as zero, returned file not 171 * necessarily zero at offset 172 * f f t sectors preallocated but read from backing_hd, 173 * returned file contains garbage at offset 174 * t t f sectors preallocated, read as zero, unknown offset 175 * t f f sectors read from unknown file or offset 176 * f t f not allocated or unknown offset, read as zero 177 * f f f not allocated or unknown offset, read from backing_hd 178 */ 179 #define BDRV_BLOCK_DATA 0x01 180 #define BDRV_BLOCK_ZERO 0x02 181 #define BDRV_BLOCK_OFFSET_VALID 0x04 182 #define BDRV_BLOCK_RAW 0x08 183 #define BDRV_BLOCK_ALLOCATED 0x10 184 #define BDRV_BLOCK_EOF 0x20 185 #define BDRV_BLOCK_RECURSE 0x40 186 187 typedef QTAILQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 188 189 typedef struct BDRVReopenState { 190 BlockDriverState *bs; 191 int flags; 192 BlockdevDetectZeroesOptions detect_zeroes; 193 bool backing_missing; 194 bool replace_backing_bs; /* new_backing_bs is ignored if this is false */ 195 BlockDriverState *new_backing_bs; /* If NULL then detach the current bs */ 196 uint64_t perm, shared_perm; 197 QDict *options; 198 QDict *explicit_options; 199 void *opaque; 200 } BDRVReopenState; 201 202 /* 203 * Block operation types 204 */ 205 typedef enum BlockOpType { 206 BLOCK_OP_TYPE_BACKUP_SOURCE, 207 BLOCK_OP_TYPE_BACKUP_TARGET, 208 BLOCK_OP_TYPE_CHANGE, 209 BLOCK_OP_TYPE_COMMIT_SOURCE, 210 BLOCK_OP_TYPE_COMMIT_TARGET, 211 BLOCK_OP_TYPE_DATAPLANE, 212 BLOCK_OP_TYPE_DRIVE_DEL, 213 BLOCK_OP_TYPE_EJECT, 214 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, 215 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, 216 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, 217 BLOCK_OP_TYPE_MIRROR_SOURCE, 218 BLOCK_OP_TYPE_MIRROR_TARGET, 219 BLOCK_OP_TYPE_RESIZE, 220 BLOCK_OP_TYPE_STREAM, 221 BLOCK_OP_TYPE_REPLACE, 222 BLOCK_OP_TYPE_MAX, 223 } BlockOpType; 224 225 /* Block node permission constants */ 226 enum { 227 /** 228 * A user that has the "permission" of consistent reads is guaranteed that 229 * their view of the contents of the block device is complete and 230 * self-consistent, representing the contents of a disk at a specific 231 * point. 232 * 233 * For most block devices (including their backing files) this is true, but 234 * the property cannot be maintained in a few situations like for 235 * intermediate nodes of a commit block job. 236 */ 237 BLK_PERM_CONSISTENT_READ = 0x01, 238 239 /** This permission is required to change the visible disk contents. */ 240 BLK_PERM_WRITE = 0x02, 241 242 /** 243 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and 244 * required for writes to the block node when the caller promises that 245 * the visible disk content doesn't change. 246 * 247 * As the BLK_PERM_WRITE permission is strictly stronger, either is 248 * sufficient to perform an unchanging write. 249 */ 250 BLK_PERM_WRITE_UNCHANGED = 0x04, 251 252 /** This permission is required to change the size of a block node. */ 253 BLK_PERM_RESIZE = 0x08, 254 255 /** 256 * This permission is required to change the node that this BdrvChild 257 * points to. 258 */ 259 BLK_PERM_GRAPH_MOD = 0x10, 260 261 BLK_PERM_ALL = 0x1f, 262 263 DEFAULT_PERM_PASSTHROUGH = BLK_PERM_CONSISTENT_READ 264 | BLK_PERM_WRITE 265 | BLK_PERM_WRITE_UNCHANGED 266 | BLK_PERM_RESIZE, 267 268 DEFAULT_PERM_UNCHANGED = BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH, 269 }; 270 271 char *bdrv_perm_names(uint64_t perm); 272 uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm); 273 274 /* disk I/O throttling */ 275 void bdrv_init(void); 276 void bdrv_init_with_whitelist(void); 277 bool bdrv_uses_whitelist(void); 278 int bdrv_is_whitelisted(BlockDriver *drv, bool read_only); 279 BlockDriver *bdrv_find_protocol(const char *filename, 280 bool allow_protocol_prefix, 281 Error **errp); 282 BlockDriver *bdrv_find_format(const char *format_name); 283 int bdrv_create(BlockDriver *drv, const char* filename, 284 QemuOpts *opts, Error **errp); 285 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 286 BlockDriverState *bdrv_new(void); 287 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 288 Error **errp); 289 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 290 Error **errp); 291 292 int bdrv_parse_aio(const char *mode, int *flags); 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, bool exact, 341 PreallocMode prealloc, Error **errp); 342 int bdrv_truncate(BdrvChild *child, int64_t offset, bool exact, 343 PreallocMode prealloc, 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 /* check if a named node can be replaced when doing drive-mirror */ 395 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 396 const char *node_name, Error **errp); 397 398 /* async block I/O */ 399 void bdrv_aio_cancel(BlockAIOCB *acb); 400 void bdrv_aio_cancel_async(BlockAIOCB *acb); 401 402 /* sg packet commands */ 403 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 404 405 /* Invalidate any cached metadata used by image formats */ 406 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp); 407 void bdrv_invalidate_cache_all(Error **errp); 408 int bdrv_inactivate_all(void); 409 410 /* Ensure contents are flushed to disk. */ 411 int bdrv_flush(BlockDriverState *bs); 412 int coroutine_fn bdrv_co_flush(BlockDriverState *bs); 413 int bdrv_flush_all(void); 414 void bdrv_close_all(void); 415 void bdrv_drain(BlockDriverState *bs); 416 void coroutine_fn bdrv_co_drain(BlockDriverState *bs); 417 void bdrv_drain_all_begin(void); 418 void bdrv_drain_all_end(void); 419 void bdrv_drain_all(void); 420 421 #define BDRV_POLL_WHILE(bs, cond) ({ \ 422 BlockDriverState *bs_ = (bs); \ 423 AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \ 424 cond); }) 425 426 int bdrv_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); 427 int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); 428 int bdrv_has_zero_init_1(BlockDriverState *bs); 429 int bdrv_has_zero_init(BlockDriverState *bs); 430 int bdrv_has_zero_init_truncate(BlockDriverState *bs); 431 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs); 432 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); 433 int bdrv_block_status(BlockDriverState *bs, int64_t offset, 434 int64_t bytes, int64_t *pnum, int64_t *map, 435 BlockDriverState **file); 436 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, 437 int64_t offset, int64_t bytes, int64_t *pnum, 438 int64_t *map, BlockDriverState **file); 439 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, 440 int64_t *pnum); 441 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, 442 bool include_base, int64_t offset, int64_t bytes, 443 int64_t *pnum); 444 445 bool bdrv_is_read_only(BlockDriverState *bs); 446 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, 447 bool ignore_allow_rdw, Error **errp); 448 int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, 449 Error **errp); 450 bool bdrv_is_writable(BlockDriverState *bs); 451 bool bdrv_is_sg(BlockDriverState *bs); 452 bool bdrv_is_inserted(BlockDriverState *bs); 453 void bdrv_lock_medium(BlockDriverState *bs, bool locked); 454 void bdrv_eject(BlockDriverState *bs, bool eject_flag); 455 const char *bdrv_get_format_name(BlockDriverState *bs); 456 BlockDriverState *bdrv_find_node(const char *node_name); 457 BlockDeviceInfoList *bdrv_named_nodes_list(bool flat, Error **errp); 458 XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp); 459 BlockDriverState *bdrv_lookup_bs(const char *device, 460 const char *node_name, 461 Error **errp); 462 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 463 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 464 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs); 465 466 typedef struct BdrvNextIterator { 467 enum { 468 BDRV_NEXT_BACKEND_ROOTS, 469 BDRV_NEXT_MONITOR_OWNED, 470 } phase; 471 BlockBackend *blk; 472 BlockDriverState *bs; 473 } BdrvNextIterator; 474 475 BlockDriverState *bdrv_first(BdrvNextIterator *it); 476 BlockDriverState *bdrv_next(BdrvNextIterator *it); 477 void bdrv_next_cleanup(BdrvNextIterator *it); 478 479 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 480 bool bdrv_is_encrypted(BlockDriverState *bs); 481 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 482 void *opaque, bool read_only); 483 const char *bdrv_get_node_name(const BlockDriverState *bs); 484 const char *bdrv_get_device_name(const BlockDriverState *bs); 485 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs); 486 int bdrv_get_flags(BlockDriverState *bs); 487 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); 488 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs, 489 Error **errp); 490 BlockStatsSpecific *bdrv_get_specific_stats(BlockDriverState *bs); 491 void bdrv_round_to_clusters(BlockDriverState *bs, 492 int64_t offset, int64_t bytes, 493 int64_t *cluster_offset, 494 int64_t *cluster_bytes); 495 496 void bdrv_get_backing_filename(BlockDriverState *bs, 497 char *filename, int filename_size); 498 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); 499 char *bdrv_get_full_backing_filename_from_filename(const char *backed, 500 const char *backing, 501 Error **errp); 502 char *bdrv_dirname(BlockDriverState *bs, Error **errp); 503 504 int path_has_protocol(const char *path); 505 int path_is_absolute(const char *path); 506 char *path_combine(const char *base_path, const char *filename); 507 508 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 509 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 510 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 511 int64_t pos, int size); 512 513 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 514 int64_t pos, int size); 515 516 void bdrv_img_create(const char *filename, const char *fmt, 517 const char *base_filename, const char *base_fmt, 518 char *options, uint64_t img_size, int flags, 519 bool quiet, Error **errp); 520 521 /* Returns the alignment in bytes that is required so that no bounce buffer 522 * is required throughout the stack */ 523 size_t bdrv_min_mem_align(BlockDriverState *bs); 524 /* Returns optimal alignment in bytes for bounce buffer */ 525 size_t bdrv_opt_mem_align(BlockDriverState *bs); 526 void *qemu_blockalign(BlockDriverState *bs, size_t size); 527 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 528 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 529 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 530 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 531 532 void bdrv_enable_copy_on_read(BlockDriverState *bs); 533 void bdrv_disable_copy_on_read(BlockDriverState *bs); 534 535 void bdrv_ref(BlockDriverState *bs); 536 void bdrv_unref(BlockDriverState *bs); 537 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 538 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 539 BlockDriverState *child_bs, 540 const char *child_name, 541 const BdrvChildRole *child_role, 542 Error **errp); 543 544 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 545 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 546 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 547 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 548 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 549 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 550 551 #define BLKDBG_EVENT(child, evt) \ 552 do { \ 553 if (child) { \ 554 bdrv_debug_event(child->bs, evt); \ 555 } \ 556 } while (0) 557 558 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 559 560 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 561 const char *tag); 562 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 563 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 564 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 565 566 /** 567 * bdrv_get_aio_context: 568 * 569 * Returns: the currently bound #AioContext 570 */ 571 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 572 573 /** 574 * Transfer control to @co in the aio context of @bs 575 */ 576 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 577 578 void bdrv_set_aio_context_ignore(BlockDriverState *bs, 579 AioContext *new_context, GSList **ignore); 580 int bdrv_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 581 Error **errp); 582 int bdrv_child_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 583 BdrvChild *ignore_child, Error **errp); 584 bool bdrv_child_can_set_aio_context(BdrvChild *c, AioContext *ctx, 585 GSList **ignore, Error **errp); 586 bool bdrv_can_set_aio_context(BlockDriverState *bs, AioContext *ctx, 587 GSList **ignore, Error **errp); 588 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 589 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 590 591 void bdrv_io_plug(BlockDriverState *bs); 592 void bdrv_io_unplug(BlockDriverState *bs); 593 594 /** 595 * bdrv_parent_drained_begin_single: 596 * 597 * Begin a quiesced section for the parent of @c. If @poll is true, wait for 598 * any pending activity to cease. 599 */ 600 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); 601 602 /** 603 * bdrv_parent_drained_end_single: 604 * 605 * End a quiesced section for the parent of @c. 606 * 607 * This polls @bs's AioContext until all scheduled sub-drained_ends 608 * have settled, which may result in graph changes. 609 */ 610 void bdrv_parent_drained_end_single(BdrvChild *c); 611 612 /** 613 * bdrv_drain_poll: 614 * 615 * Poll for pending requests in @bs, its parents (except for @ignore_parent), 616 * and if @recursive is true its children as well (used for subtree drain). 617 * 618 * If @ignore_bds_parents is true, parents that are BlockDriverStates must 619 * ignore the drain request because they will be drained separately (used for 620 * drain_all). 621 * 622 * This is part of bdrv_drained_begin. 623 */ 624 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, 625 BdrvChild *ignore_parent, bool ignore_bds_parents); 626 627 /** 628 * bdrv_drained_begin: 629 * 630 * Begin a quiesced section for exclusive access to the BDS, by disabling 631 * external request sources including NBD server and device model. Note that 632 * this doesn't block timers or coroutines from submitting more requests, which 633 * means block_job_pause is still necessary. 634 * 635 * This function can be recursive. 636 */ 637 void bdrv_drained_begin(BlockDriverState *bs); 638 639 /** 640 * bdrv_do_drained_begin_quiesce: 641 * 642 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already 643 * running requests to complete. 644 */ 645 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, 646 BdrvChild *parent, bool ignore_bds_parents); 647 648 /** 649 * Like bdrv_drained_begin, but recursively begins a quiesced section for 650 * exclusive access to all child nodes as well. 651 */ 652 void bdrv_subtree_drained_begin(BlockDriverState *bs); 653 654 /** 655 * bdrv_drained_end: 656 * 657 * End a quiescent section started by bdrv_drained_begin(). 658 * 659 * This polls @bs's AioContext until all scheduled sub-drained_ends 660 * have settled. On one hand, that may result in graph changes. On 661 * the other, this requires that the caller either runs in the main 662 * loop; or that all involved nodes (@bs and all of its parents) are 663 * in the caller's AioContext. 664 */ 665 void bdrv_drained_end(BlockDriverState *bs); 666 667 /** 668 * bdrv_drained_end_no_poll: 669 * 670 * Same as bdrv_drained_end(), but do not poll for the subgraph to 671 * actually become unquiesced. Therefore, no graph changes will occur 672 * with this function. 673 * 674 * *drained_end_counter is incremented for every background operation 675 * that is scheduled, and will be decremented for every operation once 676 * it settles. The caller must poll until it reaches 0. The counter 677 * should be accessed using atomic operations only. 678 */ 679 void bdrv_drained_end_no_poll(BlockDriverState *bs, int *drained_end_counter); 680 681 /** 682 * End a quiescent section started by bdrv_subtree_drained_begin(). 683 */ 684 void bdrv_subtree_drained_end(BlockDriverState *bs); 685 686 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 687 Error **errp); 688 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 689 690 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, 691 uint32_t granularity, Error **errp); 692 /** 693 * 694 * bdrv_register_buf/bdrv_unregister_buf: 695 * 696 * Register/unregister a buffer for I/O. For example, VFIO drivers are 697 * interested to know the memory areas that would later be used for I/O, so 698 * that they can prepare IOMMU mapping etc., to get better performance. 699 */ 700 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); 701 void bdrv_unregister_buf(BlockDriverState *bs, void *host); 702 703 /** 704 * 705 * bdrv_co_copy_range: 706 * 707 * Do offloaded copy between two children. If the operation is not implemented 708 * by the driver, or if the backend storage doesn't support it, a negative 709 * error code will be returned. 710 * 711 * Note: block layer doesn't emulate or fallback to a bounce buffer approach 712 * because usually the caller shouldn't attempt offloaded copy any more (e.g. 713 * calling copy_file_range(2)) after the first error, thus it should fall back 714 * to a read+write path in the caller level. 715 * 716 * @src: Source child to copy data from 717 * @src_offset: offset in @src image to read data 718 * @dst: Destination child to copy data to 719 * @dst_offset: offset in @dst image to write data 720 * @bytes: number of bytes to copy 721 * @flags: request flags. Supported flags: 722 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero 723 * write on @dst as if bdrv_co_pwrite_zeroes is 724 * called. Used to simplify caller code, or 725 * during BlockDriver.bdrv_co_copy_range_from() 726 * recursion. 727 * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping 728 * requests currently in flight. 729 * 730 * Returns: 0 if succeeded; negative error code if failed. 731 **/ 732 int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset, 733 BdrvChild *dst, uint64_t dst_offset, 734 uint64_t bytes, BdrvRequestFlags read_flags, 735 BdrvRequestFlags write_flags); 736 #endif 737