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 /* 14 * generated_co_wrapper 15 * 16 * Function specifier, which does nothing but mark functions to be 17 * generated by scripts/block-coroutine-wrapper.py 18 * 19 * Read more in docs/devel/block-coroutine-wrapper.rst 20 */ 21 #define generated_co_wrapper 22 23 /* block.c */ 24 typedef struct BlockDriver BlockDriver; 25 typedef struct BdrvChild BdrvChild; 26 typedef struct BdrvChildClass BdrvChildClass; 27 28 typedef struct BlockDriverInfo { 29 /* in bytes, 0 if irrelevant */ 30 int cluster_size; 31 /* offset at which the VM state can be saved (0 if not possible) */ 32 int64_t vm_state_offset; 33 bool is_dirty; 34 /* 35 * True if this block driver only supports compressed writes 36 */ 37 bool needs_compressed_writes; 38 } BlockDriverInfo; 39 40 typedef struct BlockFragInfo { 41 uint64_t allocated_clusters; 42 uint64_t total_clusters; 43 uint64_t fragmented_clusters; 44 uint64_t compressed_clusters; 45 } BlockFragInfo; 46 47 typedef enum { 48 BDRV_REQ_COPY_ON_READ = 0x1, 49 BDRV_REQ_ZERO_WRITE = 0x2, 50 51 /* 52 * The BDRV_REQ_MAY_UNMAP flag is used in write_zeroes requests to indicate 53 * that the block driver should unmap (discard) blocks if it is guaranteed 54 * that the result will read back as zeroes. The flag is only passed to the 55 * driver if the block device is opened with BDRV_O_UNMAP. 56 */ 57 BDRV_REQ_MAY_UNMAP = 0x4, 58 59 BDRV_REQ_FUA = 0x10, 60 BDRV_REQ_WRITE_COMPRESSED = 0x20, 61 62 /* Signifies that this write request will not change the visible disk 63 * content. */ 64 BDRV_REQ_WRITE_UNCHANGED = 0x40, 65 66 /* 67 * BDRV_REQ_SERIALISING forces request serialisation for writes. 68 * It is used to ensure that writes to the backing file of a backup process 69 * target cannot race with a read of the backup target that defers to the 70 * backing file. 71 * 72 * Note, that BDRV_REQ_SERIALISING is _not_ opposite in meaning to 73 * BDRV_REQ_NO_SERIALISING. A more descriptive name for the latter might be 74 * _DO_NOT_WAIT_FOR_SERIALISING, except that is too long. 75 */ 76 BDRV_REQ_SERIALISING = 0x80, 77 78 /* Execute the request only if the operation can be offloaded or otherwise 79 * be executed efficiently, but return an error instead of using a slow 80 * fallback. */ 81 BDRV_REQ_NO_FALLBACK = 0x100, 82 83 /* 84 * BDRV_REQ_PREFETCH may be used only together with BDRV_REQ_COPY_ON_READ 85 * on read request and means that caller doesn't really need data to be 86 * written to qiov parameter which may be NULL. 87 */ 88 BDRV_REQ_PREFETCH = 0x200, 89 /* Mask of valid flags */ 90 BDRV_REQ_MASK = 0x3ff, 91 } BdrvRequestFlags; 92 93 typedef struct BlockSizes { 94 uint32_t phys; 95 uint32_t log; 96 } BlockSizes; 97 98 typedef struct HDGeometry { 99 uint32_t heads; 100 uint32_t sectors; 101 uint32_t cylinders; 102 } HDGeometry; 103 104 #define BDRV_O_RDWR 0x0002 105 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */ 106 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */ 107 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */ 108 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ 109 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */ 110 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */ 111 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */ 112 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */ 113 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */ 114 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */ 115 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */ 116 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */ 117 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given: 118 select an appropriate protocol driver, 119 ignoring the format layer */ 120 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */ 121 #define BDRV_O_AUTO_RDONLY 0x20000 /* degrade to read-only if opening read-write fails */ 122 #define BDRV_O_IO_URING 0x40000 /* use io_uring instead of the thread pool */ 123 124 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 125 126 127 /* Option names of options parsed by the block layer */ 128 129 #define BDRV_OPT_CACHE_WB "cache.writeback" 130 #define BDRV_OPT_CACHE_DIRECT "cache.direct" 131 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush" 132 #define BDRV_OPT_READ_ONLY "read-only" 133 #define BDRV_OPT_AUTO_READ_ONLY "auto-read-only" 134 #define BDRV_OPT_DISCARD "discard" 135 #define BDRV_OPT_FORCE_SHARE "force-share" 136 137 138 #define BDRV_SECTOR_BITS 9 139 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS) 140 141 #define BDRV_REQUEST_MAX_SECTORS MIN_CONST(SIZE_MAX >> BDRV_SECTOR_BITS, \ 142 INT_MAX >> BDRV_SECTOR_BITS) 143 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) 144 145 /* 146 * Allocation status flags for bdrv_block_status() and friends. 147 * 148 * Public flags: 149 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer 150 * BDRV_BLOCK_ZERO: offset reads as zero 151 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data 152 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this 153 * layer rather than any backing, set by block layer 154 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this 155 * layer, set by block layer 156 * 157 * Internal flags: 158 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request 159 * that the block layer recompute the answer from the returned 160 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID. 161 * BDRV_BLOCK_RECURSE: request that the block layer will recursively search for 162 * zeroes in file child of current block node inside 163 * returned region. Only valid together with both 164 * BDRV_BLOCK_DATA and BDRV_BLOCK_OFFSET_VALID. Should not 165 * appear with BDRV_BLOCK_ZERO. 166 * 167 * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the 168 * host offset within the returned BDS that is allocated for the 169 * corresponding raw guest data. However, whether that offset 170 * actually contains data also depends on BDRV_BLOCK_DATA, as follows: 171 * 172 * DATA ZERO OFFSET_VALID 173 * t t t sectors read as zero, returned file is zero at offset 174 * t f t sectors read as valid from file at offset 175 * f t t sectors preallocated, read as zero, returned file not 176 * necessarily zero at offset 177 * f f t sectors preallocated but read from backing_hd, 178 * returned file contains garbage at offset 179 * t t f sectors preallocated, read as zero, unknown offset 180 * t f f sectors read from unknown file or offset 181 * f t f not allocated or unknown offset, read as zero 182 * f f f not allocated or unknown offset, read from backing_hd 183 */ 184 #define BDRV_BLOCK_DATA 0x01 185 #define BDRV_BLOCK_ZERO 0x02 186 #define BDRV_BLOCK_OFFSET_VALID 0x04 187 #define BDRV_BLOCK_RAW 0x08 188 #define BDRV_BLOCK_ALLOCATED 0x10 189 #define BDRV_BLOCK_EOF 0x20 190 #define BDRV_BLOCK_RECURSE 0x40 191 192 typedef QTAILQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 193 194 typedef struct BDRVReopenState { 195 BlockDriverState *bs; 196 int flags; 197 BlockdevDetectZeroesOptions detect_zeroes; 198 bool backing_missing; 199 bool replace_backing_bs; /* new_backing_bs is ignored if this is false */ 200 BlockDriverState *new_backing_bs; /* If NULL then detach the current bs */ 201 uint64_t perm, shared_perm; 202 QDict *options; 203 QDict *explicit_options; 204 void *opaque; 205 } BDRVReopenState; 206 207 /* 208 * Block operation types 209 */ 210 typedef enum BlockOpType { 211 BLOCK_OP_TYPE_BACKUP_SOURCE, 212 BLOCK_OP_TYPE_BACKUP_TARGET, 213 BLOCK_OP_TYPE_CHANGE, 214 BLOCK_OP_TYPE_COMMIT_SOURCE, 215 BLOCK_OP_TYPE_COMMIT_TARGET, 216 BLOCK_OP_TYPE_DATAPLANE, 217 BLOCK_OP_TYPE_DRIVE_DEL, 218 BLOCK_OP_TYPE_EJECT, 219 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, 220 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, 221 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, 222 BLOCK_OP_TYPE_MIRROR_SOURCE, 223 BLOCK_OP_TYPE_MIRROR_TARGET, 224 BLOCK_OP_TYPE_RESIZE, 225 BLOCK_OP_TYPE_STREAM, 226 BLOCK_OP_TYPE_REPLACE, 227 BLOCK_OP_TYPE_MAX, 228 } BlockOpType; 229 230 /* Block node permission constants */ 231 enum { 232 /** 233 * A user that has the "permission" of consistent reads is guaranteed that 234 * their view of the contents of the block device is complete and 235 * self-consistent, representing the contents of a disk at a specific 236 * point. 237 * 238 * For most block devices (including their backing files) this is true, but 239 * the property cannot be maintained in a few situations like for 240 * intermediate nodes of a commit block job. 241 */ 242 BLK_PERM_CONSISTENT_READ = 0x01, 243 244 /** This permission is required to change the visible disk contents. */ 245 BLK_PERM_WRITE = 0x02, 246 247 /** 248 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and 249 * required for writes to the block node when the caller promises that 250 * the visible disk content doesn't change. 251 * 252 * As the BLK_PERM_WRITE permission is strictly stronger, either is 253 * sufficient to perform an unchanging write. 254 */ 255 BLK_PERM_WRITE_UNCHANGED = 0x04, 256 257 /** This permission is required to change the size of a block node. */ 258 BLK_PERM_RESIZE = 0x08, 259 260 /** 261 * This permission is required to change the node that this BdrvChild 262 * points to. 263 */ 264 BLK_PERM_GRAPH_MOD = 0x10, 265 266 BLK_PERM_ALL = 0x1f, 267 268 DEFAULT_PERM_PASSTHROUGH = BLK_PERM_CONSISTENT_READ 269 | BLK_PERM_WRITE 270 | BLK_PERM_WRITE_UNCHANGED 271 | BLK_PERM_RESIZE, 272 273 DEFAULT_PERM_UNCHANGED = BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH, 274 }; 275 276 /* 277 * Flags that parent nodes assign to child nodes to specify what kind of 278 * role(s) they take. 279 * 280 * At least one of DATA, METADATA, FILTERED, or COW must be set for 281 * every child. 282 */ 283 enum BdrvChildRoleBits { 284 /* 285 * This child stores data. 286 * Any node may have an arbitrary number of such children. 287 */ 288 BDRV_CHILD_DATA = (1 << 0), 289 290 /* 291 * This child stores metadata. 292 * Any node may have an arbitrary number of metadata-storing 293 * children. 294 */ 295 BDRV_CHILD_METADATA = (1 << 1), 296 297 /* 298 * A child that always presents exactly the same visible data as 299 * the parent, e.g. by virtue of the parent forwarding all reads 300 * and writes. 301 * This flag is mutually exclusive with DATA, METADATA, and COW. 302 * Any node may have at most one filtered child at a time. 303 */ 304 BDRV_CHILD_FILTERED = (1 << 2), 305 306 /* 307 * Child from which to read all data that isn't allocated in the 308 * parent (i.e., the backing child); such data is copied to the 309 * parent through COW (and optionally COR). 310 * This field is mutually exclusive with DATA, METADATA, and 311 * FILTERED. 312 * Any node may have at most one such backing child at a time. 313 */ 314 BDRV_CHILD_COW = (1 << 3), 315 316 /* 317 * The primary child. For most drivers, this is the child whose 318 * filename applies best to the parent node. 319 * Any node may have at most one primary child at a time. 320 */ 321 BDRV_CHILD_PRIMARY = (1 << 4), 322 323 /* Useful combination of flags */ 324 BDRV_CHILD_IMAGE = BDRV_CHILD_DATA 325 | BDRV_CHILD_METADATA 326 | BDRV_CHILD_PRIMARY, 327 }; 328 329 /* Mask of BdrvChildRoleBits values */ 330 typedef unsigned int BdrvChildRole; 331 332 char *bdrv_perm_names(uint64_t perm); 333 uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm); 334 335 /* disk I/O throttling */ 336 void bdrv_init(void); 337 void bdrv_init_with_whitelist(void); 338 bool bdrv_uses_whitelist(void); 339 int bdrv_is_whitelisted(BlockDriver *drv, bool read_only); 340 BlockDriver *bdrv_find_protocol(const char *filename, 341 bool allow_protocol_prefix, 342 Error **errp); 343 BlockDriver *bdrv_find_format(const char *format_name); 344 int bdrv_create(BlockDriver *drv, const char* filename, 345 QemuOpts *opts, Error **errp); 346 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 347 348 BlockDriverState *bdrv_new(void); 349 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 350 Error **errp); 351 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 352 Error **errp); 353 354 int bdrv_parse_aio(const char *mode, int *flags); 355 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough); 356 int bdrv_parse_discard_flags(const char *mode, int *flags); 357 BdrvChild *bdrv_open_child(const char *filename, 358 QDict *options, const char *bdref_key, 359 BlockDriverState* parent, 360 const BdrvChildClass *child_class, 361 BdrvChildRole child_role, 362 bool allow_none, Error **errp); 363 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp); 364 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 365 Error **errp); 366 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 367 const char *bdref_key, Error **errp); 368 BlockDriverState *bdrv_open(const char *filename, const char *reference, 369 QDict *options, int flags, Error **errp); 370 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 371 int flags, Error **errp); 372 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 373 BlockDriverState *bs, QDict *options, 374 bool keep_old_opts); 375 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp); 376 int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, 377 Error **errp); 378 int bdrv_reopen_prepare(BDRVReopenState *reopen_state, 379 BlockReopenQueue *queue, Error **errp); 380 void bdrv_reopen_commit(BDRVReopenState *reopen_state); 381 void bdrv_reopen_abort(BDRVReopenState *reopen_state); 382 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, 383 int bytes, BdrvRequestFlags flags); 384 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); 385 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes); 386 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes); 387 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, 388 const void *buf, int count); 389 /* 390 * Efficiently zero a region of the disk image. Note that this is a regular 391 * I/O request like read or write and should have a reasonable size. This 392 * function is not suitable for zeroing the entire image in a single request 393 * because it may allocate memory for the entire region. 394 */ 395 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, 396 int bytes, BdrvRequestFlags flags); 397 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 398 const char *backing_file); 399 void bdrv_refresh_filename(BlockDriverState *bs); 400 401 int coroutine_fn bdrv_co_truncate(BdrvChild *child, int64_t offset, bool exact, 402 PreallocMode prealloc, BdrvRequestFlags flags, 403 Error **errp); 404 int generated_co_wrapper 405 bdrv_truncate(BdrvChild *child, int64_t offset, bool exact, 406 PreallocMode prealloc, BdrvRequestFlags flags, Error **errp); 407 408 int64_t bdrv_nb_sectors(BlockDriverState *bs); 409 int64_t bdrv_getlength(BlockDriverState *bs); 410 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); 411 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, 412 BlockDriverState *in_bs, Error **errp); 413 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr); 414 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp); 415 int bdrv_commit(BlockDriverState *bs); 416 int bdrv_make_empty(BdrvChild *c, Error **errp); 417 int bdrv_change_backing_file(BlockDriverState *bs, const char *backing_file, 418 const char *backing_fmt, bool warn); 419 void bdrv_register(BlockDriver *bdrv); 420 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 421 const char *backing_file_str); 422 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 423 BlockDriverState *bs); 424 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 425 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base, 426 Error **errp); 427 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base, 428 Error **errp); 429 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base); 430 int coroutine_fn bdrv_co_delete_file(BlockDriverState *bs, Error **errp); 431 432 433 typedef struct BdrvCheckResult { 434 int corruptions; 435 int leaks; 436 int check_errors; 437 int corruptions_fixed; 438 int leaks_fixed; 439 int64_t image_end_offset; 440 BlockFragInfo bfi; 441 } BdrvCheckResult; 442 443 typedef enum { 444 BDRV_FIX_LEAKS = 1, 445 BDRV_FIX_ERRORS = 2, 446 } BdrvCheckMode; 447 448 int generated_co_wrapper bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, 449 BdrvCheckMode fix); 450 451 /* The units of offset and total_work_size may be chosen arbitrarily by the 452 * block driver; total_work_size may change during the course of the amendment 453 * operation */ 454 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 455 int64_t total_work_size, void *opaque); 456 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 457 BlockDriverAmendStatusCB *status_cb, void *cb_opaque, 458 bool force, 459 Error **errp); 460 461 /* check if a named node can be replaced when doing drive-mirror */ 462 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 463 const char *node_name, Error **errp); 464 465 /* async block I/O */ 466 void bdrv_aio_cancel(BlockAIOCB *acb); 467 void bdrv_aio_cancel_async(BlockAIOCB *acb); 468 469 /* sg packet commands */ 470 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 471 472 /* Invalidate any cached metadata used by image formats */ 473 int generated_co_wrapper bdrv_invalidate_cache(BlockDriverState *bs, 474 Error **errp); 475 void bdrv_invalidate_cache_all(Error **errp); 476 int bdrv_inactivate_all(void); 477 478 /* Ensure contents are flushed to disk. */ 479 int generated_co_wrapper bdrv_flush(BlockDriverState *bs); 480 int coroutine_fn bdrv_co_flush(BlockDriverState *bs); 481 int bdrv_flush_all(void); 482 void bdrv_close_all(void); 483 void bdrv_drain(BlockDriverState *bs); 484 void coroutine_fn bdrv_co_drain(BlockDriverState *bs); 485 void bdrv_drain_all_begin(void); 486 void bdrv_drain_all_end(void); 487 void bdrv_drain_all(void); 488 489 #define BDRV_POLL_WHILE(bs, cond) ({ \ 490 BlockDriverState *bs_ = (bs); \ 491 AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \ 492 cond); }) 493 494 int generated_co_wrapper bdrv_pdiscard(BdrvChild *child, int64_t offset, 495 int64_t bytes); 496 int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); 497 int bdrv_has_zero_init_1(BlockDriverState *bs); 498 int bdrv_has_zero_init(BlockDriverState *bs); 499 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); 500 int bdrv_block_status(BlockDriverState *bs, int64_t offset, 501 int64_t bytes, int64_t *pnum, int64_t *map, 502 BlockDriverState **file); 503 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, 504 int64_t offset, int64_t bytes, int64_t *pnum, 505 int64_t *map, BlockDriverState **file); 506 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, 507 int64_t *pnum); 508 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, 509 bool include_base, int64_t offset, int64_t bytes, 510 int64_t *pnum); 511 512 bool bdrv_is_read_only(BlockDriverState *bs); 513 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, 514 bool ignore_allow_rdw, Error **errp); 515 int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, 516 Error **errp); 517 bool bdrv_is_writable(BlockDriverState *bs); 518 bool bdrv_is_sg(BlockDriverState *bs); 519 bool bdrv_is_inserted(BlockDriverState *bs); 520 void bdrv_lock_medium(BlockDriverState *bs, bool locked); 521 void bdrv_eject(BlockDriverState *bs, bool eject_flag); 522 const char *bdrv_get_format_name(BlockDriverState *bs); 523 BlockDriverState *bdrv_find_node(const char *node_name); 524 BlockDeviceInfoList *bdrv_named_nodes_list(bool flat, Error **errp); 525 XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp); 526 BlockDriverState *bdrv_lookup_bs(const char *device, 527 const char *node_name, 528 Error **errp); 529 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 530 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 531 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs); 532 533 typedef struct BdrvNextIterator { 534 enum { 535 BDRV_NEXT_BACKEND_ROOTS, 536 BDRV_NEXT_MONITOR_OWNED, 537 } phase; 538 BlockBackend *blk; 539 BlockDriverState *bs; 540 } BdrvNextIterator; 541 542 BlockDriverState *bdrv_first(BdrvNextIterator *it); 543 BlockDriverState *bdrv_next(BdrvNextIterator *it); 544 void bdrv_next_cleanup(BdrvNextIterator *it); 545 546 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 547 bool bdrv_supports_compressed_writes(BlockDriverState *bs); 548 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 549 void *opaque, bool read_only); 550 const char *bdrv_get_node_name(const BlockDriverState *bs); 551 const char *bdrv_get_device_name(const BlockDriverState *bs); 552 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs); 553 int bdrv_get_flags(BlockDriverState *bs); 554 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); 555 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs, 556 Error **errp); 557 BlockStatsSpecific *bdrv_get_specific_stats(BlockDriverState *bs); 558 void bdrv_round_to_clusters(BlockDriverState *bs, 559 int64_t offset, int64_t bytes, 560 int64_t *cluster_offset, 561 int64_t *cluster_bytes); 562 563 void bdrv_get_backing_filename(BlockDriverState *bs, 564 char *filename, int filename_size); 565 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); 566 char *bdrv_get_full_backing_filename_from_filename(const char *backed, 567 const char *backing, 568 Error **errp); 569 char *bdrv_dirname(BlockDriverState *bs, Error **errp); 570 571 int path_has_protocol(const char *path); 572 int path_is_absolute(const char *path); 573 char *path_combine(const char *base_path, const char *filename); 574 575 int generated_co_wrapper 576 bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 577 int generated_co_wrapper 578 bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 579 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 580 int64_t pos, int size); 581 582 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 583 int64_t pos, int size); 584 585 void bdrv_img_create(const char *filename, const char *fmt, 586 const char *base_filename, const char *base_fmt, 587 char *options, uint64_t img_size, int flags, 588 bool quiet, Error **errp); 589 590 /* Returns the alignment in bytes that is required so that no bounce buffer 591 * is required throughout the stack */ 592 size_t bdrv_min_mem_align(BlockDriverState *bs); 593 /* Returns optimal alignment in bytes for bounce buffer */ 594 size_t bdrv_opt_mem_align(BlockDriverState *bs); 595 void *qemu_blockalign(BlockDriverState *bs, size_t size); 596 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 597 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 598 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 599 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 600 601 void bdrv_enable_copy_on_read(BlockDriverState *bs); 602 void bdrv_disable_copy_on_read(BlockDriverState *bs); 603 604 void bdrv_ref(BlockDriverState *bs); 605 void bdrv_unref(BlockDriverState *bs); 606 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 607 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 608 BlockDriverState *child_bs, 609 const char *child_name, 610 const BdrvChildClass *child_class, 611 BdrvChildRole child_role, 612 Error **errp); 613 614 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 615 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 616 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 617 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 618 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 619 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 620 621 #define BLKDBG_EVENT(child, evt) \ 622 do { \ 623 if (child) { \ 624 bdrv_debug_event(child->bs, evt); \ 625 } \ 626 } while (0) 627 628 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 629 630 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 631 const char *tag); 632 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 633 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 634 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 635 636 /** 637 * bdrv_get_aio_context: 638 * 639 * Returns: the currently bound #AioContext 640 */ 641 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 642 643 /** 644 * Move the current coroutine to the AioContext of @bs and return the old 645 * AioContext of the coroutine. Increase bs->in_flight so that draining @bs 646 * will wait for the operation to proceed until the corresponding 647 * bdrv_co_leave(). 648 * 649 * Consequently, you can't call drain inside a bdrv_co_enter/leave() section as 650 * this will deadlock. 651 */ 652 AioContext *coroutine_fn bdrv_co_enter(BlockDriverState *bs); 653 654 /** 655 * Ends a section started by bdrv_co_enter(). Move the current coroutine back 656 * to old_ctx and decrease bs->in_flight again. 657 */ 658 void coroutine_fn bdrv_co_leave(BlockDriverState *bs, AioContext *old_ctx); 659 660 /** 661 * Locks the AioContext of @bs if it's not the current AioContext. This avoids 662 * double locking which could lead to deadlocks: This is a coroutine_fn, so we 663 * know we already own the lock of the current AioContext. 664 * 665 * May only be called in the main thread. 666 */ 667 void coroutine_fn bdrv_co_lock(BlockDriverState *bs); 668 669 /** 670 * Unlocks the AioContext of @bs if it's not the current AioContext. 671 */ 672 void coroutine_fn bdrv_co_unlock(BlockDriverState *bs); 673 674 /** 675 * Transfer control to @co in the aio context of @bs 676 */ 677 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 678 679 void bdrv_set_aio_context_ignore(BlockDriverState *bs, 680 AioContext *new_context, GSList **ignore); 681 int bdrv_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 682 Error **errp); 683 int bdrv_child_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 684 BdrvChild *ignore_child, Error **errp); 685 bool bdrv_child_can_set_aio_context(BdrvChild *c, AioContext *ctx, 686 GSList **ignore, Error **errp); 687 bool bdrv_can_set_aio_context(BlockDriverState *bs, AioContext *ctx, 688 GSList **ignore, Error **errp); 689 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 690 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 691 692 void bdrv_io_plug(BlockDriverState *bs); 693 void bdrv_io_unplug(BlockDriverState *bs); 694 695 /** 696 * bdrv_parent_drained_begin_single: 697 * 698 * Begin a quiesced section for the parent of @c. If @poll is true, wait for 699 * any pending activity to cease. 700 */ 701 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); 702 703 /** 704 * bdrv_parent_drained_end_single: 705 * 706 * End a quiesced section for the parent of @c. 707 * 708 * This polls @bs's AioContext until all scheduled sub-drained_ends 709 * have settled, which may result in graph changes. 710 */ 711 void bdrv_parent_drained_end_single(BdrvChild *c); 712 713 /** 714 * bdrv_drain_poll: 715 * 716 * Poll for pending requests in @bs, its parents (except for @ignore_parent), 717 * and if @recursive is true its children as well (used for subtree drain). 718 * 719 * If @ignore_bds_parents is true, parents that are BlockDriverStates must 720 * ignore the drain request because they will be drained separately (used for 721 * drain_all). 722 * 723 * This is part of bdrv_drained_begin. 724 */ 725 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, 726 BdrvChild *ignore_parent, bool ignore_bds_parents); 727 728 /** 729 * bdrv_drained_begin: 730 * 731 * Begin a quiesced section for exclusive access to the BDS, by disabling 732 * external request sources including NBD server and device model. Note that 733 * this doesn't block timers or coroutines from submitting more requests, which 734 * means block_job_pause is still necessary. 735 * 736 * This function can be recursive. 737 */ 738 void bdrv_drained_begin(BlockDriverState *bs); 739 740 /** 741 * bdrv_do_drained_begin_quiesce: 742 * 743 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already 744 * running requests to complete. 745 */ 746 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, 747 BdrvChild *parent, bool ignore_bds_parents); 748 749 /** 750 * Like bdrv_drained_begin, but recursively begins a quiesced section for 751 * exclusive access to all child nodes as well. 752 */ 753 void bdrv_subtree_drained_begin(BlockDriverState *bs); 754 755 /** 756 * bdrv_drained_end: 757 * 758 * End a quiescent section started by bdrv_drained_begin(). 759 * 760 * This polls @bs's AioContext until all scheduled sub-drained_ends 761 * have settled. On one hand, that may result in graph changes. On 762 * the other, this requires that the caller either runs in the main 763 * loop; or that all involved nodes (@bs and all of its parents) are 764 * in the caller's AioContext. 765 */ 766 void bdrv_drained_end(BlockDriverState *bs); 767 768 /** 769 * bdrv_drained_end_no_poll: 770 * 771 * Same as bdrv_drained_end(), but do not poll for the subgraph to 772 * actually become unquiesced. Therefore, no graph changes will occur 773 * with this function. 774 * 775 * *drained_end_counter is incremented for every background operation 776 * that is scheduled, and will be decremented for every operation once 777 * it settles. The caller must poll until it reaches 0. The counter 778 * should be accessed using atomic operations only. 779 */ 780 void bdrv_drained_end_no_poll(BlockDriverState *bs, int *drained_end_counter); 781 782 /** 783 * End a quiescent section started by bdrv_subtree_drained_begin(). 784 */ 785 void bdrv_subtree_drained_end(BlockDriverState *bs); 786 787 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 788 Error **errp); 789 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 790 791 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, 792 uint32_t granularity, Error **errp); 793 /** 794 * 795 * bdrv_register_buf/bdrv_unregister_buf: 796 * 797 * Register/unregister a buffer for I/O. For example, VFIO drivers are 798 * interested to know the memory areas that would later be used for I/O, so 799 * that they can prepare IOMMU mapping etc., to get better performance. 800 */ 801 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); 802 void bdrv_unregister_buf(BlockDriverState *bs, void *host); 803 804 /** 805 * 806 * bdrv_co_copy_range: 807 * 808 * Do offloaded copy between two children. If the operation is not implemented 809 * by the driver, or if the backend storage doesn't support it, a negative 810 * error code will be returned. 811 * 812 * Note: block layer doesn't emulate or fallback to a bounce buffer approach 813 * because usually the caller shouldn't attempt offloaded copy any more (e.g. 814 * calling copy_file_range(2)) after the first error, thus it should fall back 815 * to a read+write path in the caller level. 816 * 817 * @src: Source child to copy data from 818 * @src_offset: offset in @src image to read data 819 * @dst: Destination child to copy data to 820 * @dst_offset: offset in @dst image to write data 821 * @bytes: number of bytes to copy 822 * @flags: request flags. Supported flags: 823 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero 824 * write on @dst as if bdrv_co_pwrite_zeroes is 825 * called. Used to simplify caller code, or 826 * during BlockDriver.bdrv_co_copy_range_from() 827 * recursion. 828 * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping 829 * requests currently in flight. 830 * 831 * Returns: 0 if succeeded; negative error code if failed. 832 **/ 833 int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset, 834 BdrvChild *dst, uint64_t dst_offset, 835 uint64_t bytes, BdrvRequestFlags read_flags, 836 BdrvRequestFlags write_flags); 837 #endif 838