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 /* Forces request serialisation. Use only with write requests. */ 67 BDRV_REQ_SERIALISING = 0x80, 68 69 /* Execute the request only if the operation can be offloaded or otherwise 70 * be executed efficiently, but return an error instead of using a slow 71 * fallback. */ 72 BDRV_REQ_NO_FALLBACK = 0x100, 73 74 /* 75 * BDRV_REQ_PREFETCH may be used only together with BDRV_REQ_COPY_ON_READ 76 * on read request and means that caller doesn't really need data to be 77 * written to qiov parameter which may be NULL. 78 */ 79 BDRV_REQ_PREFETCH = 0x200, 80 81 /* 82 * If we need to wait for other requests, just fail immediately. Used 83 * only together with BDRV_REQ_SERIALISING. 84 */ 85 BDRV_REQ_NO_WAIT = 0x400, 86 87 /* Mask of valid flags */ 88 BDRV_REQ_MASK = 0x7ff, 89 } BdrvRequestFlags; 90 91 typedef struct BlockSizes { 92 uint32_t phys; 93 uint32_t log; 94 } BlockSizes; 95 96 typedef struct HDGeometry { 97 uint32_t heads; 98 uint32_t sectors; 99 uint32_t cylinders; 100 } HDGeometry; 101 102 #define BDRV_O_RDWR 0x0002 103 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */ 104 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */ 105 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */ 106 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ 107 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */ 108 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */ 109 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */ 110 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */ 111 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */ 112 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */ 113 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */ 114 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */ 115 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given: 116 select an appropriate protocol driver, 117 ignoring the format layer */ 118 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */ 119 #define BDRV_O_AUTO_RDONLY 0x20000 /* degrade to read-only if opening read-write fails */ 120 #define BDRV_O_IO_URING 0x40000 /* use io_uring instead of the thread pool */ 121 122 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 123 124 125 /* Option names of options parsed by the block layer */ 126 127 #define BDRV_OPT_CACHE_WB "cache.writeback" 128 #define BDRV_OPT_CACHE_DIRECT "cache.direct" 129 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush" 130 #define BDRV_OPT_READ_ONLY "read-only" 131 #define BDRV_OPT_AUTO_READ_ONLY "auto-read-only" 132 #define BDRV_OPT_DISCARD "discard" 133 #define BDRV_OPT_FORCE_SHARE "force-share" 134 135 136 #define BDRV_SECTOR_BITS 9 137 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS) 138 139 #define BDRV_REQUEST_MAX_SECTORS MIN_CONST(SIZE_MAX >> BDRV_SECTOR_BITS, \ 140 INT_MAX >> BDRV_SECTOR_BITS) 141 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) 142 143 /* 144 * We want allow aligning requests and disk length up to any 32bit alignment 145 * and don't afraid of overflow. 146 * To achieve it, and in the same time use some pretty number as maximum disk 147 * size, let's define maximum "length" (a limit for any offset/bytes request and 148 * for disk size) to be the greatest power of 2 less than INT64_MAX. 149 */ 150 #define BDRV_MAX_ALIGNMENT (1L << 30) 151 #define BDRV_MAX_LENGTH (QEMU_ALIGN_DOWN(INT64_MAX, BDRV_MAX_ALIGNMENT)) 152 153 /* 154 * Allocation status flags for bdrv_block_status() and friends. 155 * 156 * Public flags: 157 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer 158 * BDRV_BLOCK_ZERO: offset reads as zero 159 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data 160 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this 161 * layer rather than any backing, set by block layer 162 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this 163 * layer, set by block layer 164 * 165 * Internal flags: 166 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request 167 * that the block layer recompute the answer from the returned 168 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID. 169 * BDRV_BLOCK_RECURSE: request that the block layer will recursively search for 170 * zeroes in file child of current block node inside 171 * returned region. Only valid together with both 172 * BDRV_BLOCK_DATA and BDRV_BLOCK_OFFSET_VALID. Should not 173 * appear with BDRV_BLOCK_ZERO. 174 * 175 * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the 176 * host offset within the returned BDS that is allocated for the 177 * corresponding raw guest data. However, whether that offset 178 * actually contains data also depends on BDRV_BLOCK_DATA, as follows: 179 * 180 * DATA ZERO OFFSET_VALID 181 * t t t sectors read as zero, returned file is zero at offset 182 * t f t sectors read as valid from file at offset 183 * f t t sectors preallocated, read as zero, returned file not 184 * necessarily zero at offset 185 * f f t sectors preallocated but read from backing_hd, 186 * returned file contains garbage at offset 187 * t t f sectors preallocated, read as zero, unknown offset 188 * t f f sectors read from unknown file or offset 189 * f t f not allocated or unknown offset, read as zero 190 * f f f not allocated or unknown offset, read from backing_hd 191 */ 192 #define BDRV_BLOCK_DATA 0x01 193 #define BDRV_BLOCK_ZERO 0x02 194 #define BDRV_BLOCK_OFFSET_VALID 0x04 195 #define BDRV_BLOCK_RAW 0x08 196 #define BDRV_BLOCK_ALLOCATED 0x10 197 #define BDRV_BLOCK_EOF 0x20 198 #define BDRV_BLOCK_RECURSE 0x40 199 200 typedef QTAILQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 201 202 typedef struct BDRVReopenState { 203 BlockDriverState *bs; 204 int flags; 205 BlockdevDetectZeroesOptions detect_zeroes; 206 bool backing_missing; 207 bool replace_backing_bs; /* new_backing_bs is ignored if this is false */ 208 BlockDriverState *new_backing_bs; /* If NULL then detach the current bs */ 209 uint64_t perm, shared_perm; 210 QDict *options; 211 QDict *explicit_options; 212 void *opaque; 213 } BDRVReopenState; 214 215 /* 216 * Block operation types 217 */ 218 typedef enum BlockOpType { 219 BLOCK_OP_TYPE_BACKUP_SOURCE, 220 BLOCK_OP_TYPE_BACKUP_TARGET, 221 BLOCK_OP_TYPE_CHANGE, 222 BLOCK_OP_TYPE_COMMIT_SOURCE, 223 BLOCK_OP_TYPE_COMMIT_TARGET, 224 BLOCK_OP_TYPE_DATAPLANE, 225 BLOCK_OP_TYPE_DRIVE_DEL, 226 BLOCK_OP_TYPE_EJECT, 227 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, 228 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, 229 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, 230 BLOCK_OP_TYPE_MIRROR_SOURCE, 231 BLOCK_OP_TYPE_MIRROR_TARGET, 232 BLOCK_OP_TYPE_RESIZE, 233 BLOCK_OP_TYPE_STREAM, 234 BLOCK_OP_TYPE_REPLACE, 235 BLOCK_OP_TYPE_MAX, 236 } BlockOpType; 237 238 /* Block node permission constants */ 239 enum { 240 /** 241 * A user that has the "permission" of consistent reads is guaranteed that 242 * their view of the contents of the block device is complete and 243 * self-consistent, representing the contents of a disk at a specific 244 * point. 245 * 246 * For most block devices (including their backing files) this is true, but 247 * the property cannot be maintained in a few situations like for 248 * intermediate nodes of a commit block job. 249 */ 250 BLK_PERM_CONSISTENT_READ = 0x01, 251 252 /** This permission is required to change the visible disk contents. */ 253 BLK_PERM_WRITE = 0x02, 254 255 /** 256 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and 257 * required for writes to the block node when the caller promises that 258 * the visible disk content doesn't change. 259 * 260 * As the BLK_PERM_WRITE permission is strictly stronger, either is 261 * sufficient to perform an unchanging write. 262 */ 263 BLK_PERM_WRITE_UNCHANGED = 0x04, 264 265 /** This permission is required to change the size of a block node. */ 266 BLK_PERM_RESIZE = 0x08, 267 268 /** 269 * This permission is required to change the node that this BdrvChild 270 * points to. 271 */ 272 BLK_PERM_GRAPH_MOD = 0x10, 273 274 BLK_PERM_ALL = 0x1f, 275 276 DEFAULT_PERM_PASSTHROUGH = BLK_PERM_CONSISTENT_READ 277 | BLK_PERM_WRITE 278 | BLK_PERM_WRITE_UNCHANGED 279 | BLK_PERM_RESIZE, 280 281 DEFAULT_PERM_UNCHANGED = BLK_PERM_ALL & ~DEFAULT_PERM_PASSTHROUGH, 282 }; 283 284 /* 285 * Flags that parent nodes assign to child nodes to specify what kind of 286 * role(s) they take. 287 * 288 * At least one of DATA, METADATA, FILTERED, or COW must be set for 289 * every child. 290 */ 291 enum BdrvChildRoleBits { 292 /* 293 * This child stores data. 294 * Any node may have an arbitrary number of such children. 295 */ 296 BDRV_CHILD_DATA = (1 << 0), 297 298 /* 299 * This child stores metadata. 300 * Any node may have an arbitrary number of metadata-storing 301 * children. 302 */ 303 BDRV_CHILD_METADATA = (1 << 1), 304 305 /* 306 * A child that always presents exactly the same visible data as 307 * the parent, e.g. by virtue of the parent forwarding all reads 308 * and writes. 309 * This flag is mutually exclusive with DATA, METADATA, and COW. 310 * Any node may have at most one filtered child at a time. 311 */ 312 BDRV_CHILD_FILTERED = (1 << 2), 313 314 /* 315 * Child from which to read all data that isn't allocated in the 316 * parent (i.e., the backing child); such data is copied to the 317 * parent through COW (and optionally COR). 318 * This field is mutually exclusive with DATA, METADATA, and 319 * FILTERED. 320 * Any node may have at most one such backing child at a time. 321 */ 322 BDRV_CHILD_COW = (1 << 3), 323 324 /* 325 * The primary child. For most drivers, this is the child whose 326 * filename applies best to the parent node. 327 * Any node may have at most one primary child at a time. 328 */ 329 BDRV_CHILD_PRIMARY = (1 << 4), 330 331 /* Useful combination of flags */ 332 BDRV_CHILD_IMAGE = BDRV_CHILD_DATA 333 | BDRV_CHILD_METADATA 334 | BDRV_CHILD_PRIMARY, 335 }; 336 337 /* Mask of BdrvChildRoleBits values */ 338 typedef unsigned int BdrvChildRole; 339 340 char *bdrv_perm_names(uint64_t perm); 341 uint64_t bdrv_qapi_perm_to_blk_perm(BlockPermission qapi_perm); 342 343 /* disk I/O throttling */ 344 void bdrv_init(void); 345 void bdrv_init_with_whitelist(void); 346 bool bdrv_uses_whitelist(void); 347 int bdrv_is_whitelisted(BlockDriver *drv, bool read_only); 348 BlockDriver *bdrv_find_protocol(const char *filename, 349 bool allow_protocol_prefix, 350 Error **errp); 351 BlockDriver *bdrv_find_format(const char *format_name); 352 int bdrv_create(BlockDriver *drv, const char* filename, 353 QemuOpts *opts, Error **errp); 354 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 355 356 BlockDriverState *bdrv_new(void); 357 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 358 Error **errp); 359 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 360 Error **errp); 361 362 int bdrv_parse_aio(const char *mode, int *flags); 363 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough); 364 int bdrv_parse_discard_flags(const char *mode, int *flags); 365 BdrvChild *bdrv_open_child(const char *filename, 366 QDict *options, const char *bdref_key, 367 BlockDriverState* parent, 368 const BdrvChildClass *child_class, 369 BdrvChildRole child_role, 370 bool allow_none, Error **errp); 371 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp); 372 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 373 Error **errp); 374 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 375 const char *bdref_key, Error **errp); 376 BlockDriverState *bdrv_open(const char *filename, const char *reference, 377 QDict *options, int flags, Error **errp); 378 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 379 int flags, Error **errp); 380 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 381 BlockDriverState *bs, QDict *options, 382 bool keep_old_opts); 383 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp); 384 int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, 385 Error **errp); 386 int bdrv_reopen_prepare(BDRVReopenState *reopen_state, 387 BlockReopenQueue *queue, Error **errp); 388 void bdrv_reopen_commit(BDRVReopenState *reopen_state); 389 void bdrv_reopen_abort(BDRVReopenState *reopen_state); 390 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, 391 int bytes, BdrvRequestFlags flags); 392 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); 393 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes); 394 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes); 395 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, 396 const void *buf, int count); 397 /* 398 * Efficiently zero a region of the disk image. Note that this is a regular 399 * I/O request like read or write and should have a reasonable size. This 400 * function is not suitable for zeroing the entire image in a single request 401 * because it may allocate memory for the entire region. 402 */ 403 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, 404 int bytes, BdrvRequestFlags flags); 405 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 406 const char *backing_file); 407 void bdrv_refresh_filename(BlockDriverState *bs); 408 409 int coroutine_fn bdrv_co_truncate(BdrvChild *child, int64_t offset, bool exact, 410 PreallocMode prealloc, BdrvRequestFlags flags, 411 Error **errp); 412 int generated_co_wrapper 413 bdrv_truncate(BdrvChild *child, int64_t offset, bool exact, 414 PreallocMode prealloc, BdrvRequestFlags flags, Error **errp); 415 416 int64_t bdrv_nb_sectors(BlockDriverState *bs); 417 int64_t bdrv_getlength(BlockDriverState *bs); 418 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); 419 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, 420 BlockDriverState *in_bs, Error **errp); 421 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr); 422 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp); 423 int bdrv_commit(BlockDriverState *bs); 424 int bdrv_make_empty(BdrvChild *c, Error **errp); 425 int bdrv_change_backing_file(BlockDriverState *bs, const char *backing_file, 426 const char *backing_fmt, bool warn); 427 void bdrv_register(BlockDriver *bdrv); 428 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 429 const char *backing_file_str); 430 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 431 BlockDriverState *bs); 432 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 433 bool bdrv_is_backing_chain_frozen(BlockDriverState *bs, BlockDriverState *base, 434 Error **errp); 435 int bdrv_freeze_backing_chain(BlockDriverState *bs, BlockDriverState *base, 436 Error **errp); 437 void bdrv_unfreeze_backing_chain(BlockDriverState *bs, BlockDriverState *base); 438 int coroutine_fn bdrv_co_delete_file(BlockDriverState *bs, Error **errp); 439 440 441 typedef struct BdrvCheckResult { 442 int corruptions; 443 int leaks; 444 int check_errors; 445 int corruptions_fixed; 446 int leaks_fixed; 447 int64_t image_end_offset; 448 BlockFragInfo bfi; 449 } BdrvCheckResult; 450 451 typedef enum { 452 BDRV_FIX_LEAKS = 1, 453 BDRV_FIX_ERRORS = 2, 454 } BdrvCheckMode; 455 456 int generated_co_wrapper bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, 457 BdrvCheckMode fix); 458 459 /* The units of offset and total_work_size may be chosen arbitrarily by the 460 * block driver; total_work_size may change during the course of the amendment 461 * operation */ 462 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 463 int64_t total_work_size, void *opaque); 464 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 465 BlockDriverAmendStatusCB *status_cb, void *cb_opaque, 466 bool force, 467 Error **errp); 468 469 /* check if a named node can be replaced when doing drive-mirror */ 470 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 471 const char *node_name, Error **errp); 472 473 /* async block I/O */ 474 void bdrv_aio_cancel(BlockAIOCB *acb); 475 void bdrv_aio_cancel_async(BlockAIOCB *acb); 476 477 /* sg packet commands */ 478 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 479 480 /* Invalidate any cached metadata used by image formats */ 481 int generated_co_wrapper bdrv_invalidate_cache(BlockDriverState *bs, 482 Error **errp); 483 void bdrv_invalidate_cache_all(Error **errp); 484 int bdrv_inactivate_all(void); 485 486 /* Ensure contents are flushed to disk. */ 487 int generated_co_wrapper bdrv_flush(BlockDriverState *bs); 488 int coroutine_fn bdrv_co_flush(BlockDriverState *bs); 489 int bdrv_flush_all(void); 490 void bdrv_close_all(void); 491 void bdrv_drain(BlockDriverState *bs); 492 void coroutine_fn bdrv_co_drain(BlockDriverState *bs); 493 void bdrv_drain_all_begin(void); 494 void bdrv_drain_all_end(void); 495 void bdrv_drain_all(void); 496 497 #define BDRV_POLL_WHILE(bs, cond) ({ \ 498 BlockDriverState *bs_ = (bs); \ 499 AIO_WAIT_WHILE(bdrv_get_aio_context(bs_), \ 500 cond); }) 501 502 int generated_co_wrapper bdrv_pdiscard(BdrvChild *child, int64_t offset, 503 int64_t bytes); 504 int bdrv_co_pdiscard(BdrvChild *child, int64_t offset, int64_t bytes); 505 int bdrv_has_zero_init_1(BlockDriverState *bs); 506 int bdrv_has_zero_init(BlockDriverState *bs); 507 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); 508 int bdrv_block_status(BlockDriverState *bs, int64_t offset, 509 int64_t bytes, int64_t *pnum, int64_t *map, 510 BlockDriverState **file); 511 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, 512 int64_t offset, int64_t bytes, int64_t *pnum, 513 int64_t *map, BlockDriverState **file); 514 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, 515 int64_t *pnum); 516 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, 517 bool include_base, int64_t offset, int64_t bytes, 518 int64_t *pnum); 519 int coroutine_fn bdrv_co_is_zero_fast(BlockDriverState *bs, int64_t offset, 520 int64_t bytes); 521 522 bool bdrv_is_read_only(BlockDriverState *bs); 523 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, 524 bool ignore_allow_rdw, Error **errp); 525 int bdrv_apply_auto_read_only(BlockDriverState *bs, const char *errmsg, 526 Error **errp); 527 bool bdrv_is_writable(BlockDriverState *bs); 528 bool bdrv_is_sg(BlockDriverState *bs); 529 bool bdrv_is_inserted(BlockDriverState *bs); 530 void bdrv_lock_medium(BlockDriverState *bs, bool locked); 531 void bdrv_eject(BlockDriverState *bs, bool eject_flag); 532 const char *bdrv_get_format_name(BlockDriverState *bs); 533 BlockDriverState *bdrv_find_node(const char *node_name); 534 BlockDeviceInfoList *bdrv_named_nodes_list(bool flat, Error **errp); 535 XDbgBlockGraph *bdrv_get_xdbg_block_graph(Error **errp); 536 BlockDriverState *bdrv_lookup_bs(const char *device, 537 const char *node_name, 538 Error **errp); 539 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 540 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 541 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs); 542 543 typedef struct BdrvNextIterator { 544 enum { 545 BDRV_NEXT_BACKEND_ROOTS, 546 BDRV_NEXT_MONITOR_OWNED, 547 } phase; 548 BlockBackend *blk; 549 BlockDriverState *bs; 550 } BdrvNextIterator; 551 552 BlockDriverState *bdrv_first(BdrvNextIterator *it); 553 BlockDriverState *bdrv_next(BdrvNextIterator *it); 554 void bdrv_next_cleanup(BdrvNextIterator *it); 555 556 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 557 bool bdrv_supports_compressed_writes(BlockDriverState *bs); 558 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 559 void *opaque, bool read_only); 560 const char *bdrv_get_node_name(const BlockDriverState *bs); 561 const char *bdrv_get_device_name(const BlockDriverState *bs); 562 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs); 563 int bdrv_get_flags(BlockDriverState *bs); 564 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); 565 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs, 566 Error **errp); 567 BlockStatsSpecific *bdrv_get_specific_stats(BlockDriverState *bs); 568 void bdrv_round_to_clusters(BlockDriverState *bs, 569 int64_t offset, int64_t bytes, 570 int64_t *cluster_offset, 571 int64_t *cluster_bytes); 572 573 void bdrv_get_backing_filename(BlockDriverState *bs, 574 char *filename, int filename_size); 575 char *bdrv_get_full_backing_filename(BlockDriverState *bs, Error **errp); 576 char *bdrv_get_full_backing_filename_from_filename(const char *backed, 577 const char *backing, 578 Error **errp); 579 char *bdrv_dirname(BlockDriverState *bs, Error **errp); 580 581 int path_has_protocol(const char *path); 582 int path_is_absolute(const char *path); 583 char *path_combine(const char *base_path, const char *filename); 584 585 int generated_co_wrapper 586 bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 587 int generated_co_wrapper 588 bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 589 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 590 int64_t pos, int size); 591 592 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 593 int64_t pos, int size); 594 595 void bdrv_img_create(const char *filename, const char *fmt, 596 const char *base_filename, const char *base_fmt, 597 char *options, uint64_t img_size, int flags, 598 bool quiet, Error **errp); 599 600 /* Returns the alignment in bytes that is required so that no bounce buffer 601 * is required throughout the stack */ 602 size_t bdrv_min_mem_align(BlockDriverState *bs); 603 /* Returns optimal alignment in bytes for bounce buffer */ 604 size_t bdrv_opt_mem_align(BlockDriverState *bs); 605 void *qemu_blockalign(BlockDriverState *bs, size_t size); 606 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 607 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 608 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 609 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 610 611 void bdrv_enable_copy_on_read(BlockDriverState *bs); 612 void bdrv_disable_copy_on_read(BlockDriverState *bs); 613 614 void bdrv_ref(BlockDriverState *bs); 615 void bdrv_unref(BlockDriverState *bs); 616 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 617 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 618 BlockDriverState *child_bs, 619 const char *child_name, 620 const BdrvChildClass *child_class, 621 BdrvChildRole child_role, 622 Error **errp); 623 624 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 625 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 626 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 627 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 628 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 629 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 630 631 #define BLKDBG_EVENT(child, evt) \ 632 do { \ 633 if (child) { \ 634 bdrv_debug_event(child->bs, evt); \ 635 } \ 636 } while (0) 637 638 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 639 640 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 641 const char *tag); 642 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 643 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 644 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 645 646 /** 647 * bdrv_get_aio_context: 648 * 649 * Returns: the currently bound #AioContext 650 */ 651 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 652 653 /** 654 * Move the current coroutine to the AioContext of @bs and return the old 655 * AioContext of the coroutine. Increase bs->in_flight so that draining @bs 656 * will wait for the operation to proceed until the corresponding 657 * bdrv_co_leave(). 658 * 659 * Consequently, you can't call drain inside a bdrv_co_enter/leave() section as 660 * this will deadlock. 661 */ 662 AioContext *coroutine_fn bdrv_co_enter(BlockDriverState *bs); 663 664 /** 665 * Ends a section started by bdrv_co_enter(). Move the current coroutine back 666 * to old_ctx and decrease bs->in_flight again. 667 */ 668 void coroutine_fn bdrv_co_leave(BlockDriverState *bs, AioContext *old_ctx); 669 670 /** 671 * Locks the AioContext of @bs if it's not the current AioContext. This avoids 672 * double locking which could lead to deadlocks: This is a coroutine_fn, so we 673 * know we already own the lock of the current AioContext. 674 * 675 * May only be called in the main thread. 676 */ 677 void coroutine_fn bdrv_co_lock(BlockDriverState *bs); 678 679 /** 680 * Unlocks the AioContext of @bs if it's not the current AioContext. 681 */ 682 void coroutine_fn bdrv_co_unlock(BlockDriverState *bs); 683 684 /** 685 * Transfer control to @co in the aio context of @bs 686 */ 687 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 688 689 void bdrv_set_aio_context_ignore(BlockDriverState *bs, 690 AioContext *new_context, GSList **ignore); 691 int bdrv_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 692 Error **errp); 693 int bdrv_child_try_set_aio_context(BlockDriverState *bs, AioContext *ctx, 694 BdrvChild *ignore_child, Error **errp); 695 bool bdrv_child_can_set_aio_context(BdrvChild *c, AioContext *ctx, 696 GSList **ignore, Error **errp); 697 bool bdrv_can_set_aio_context(BlockDriverState *bs, AioContext *ctx, 698 GSList **ignore, Error **errp); 699 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 700 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 701 702 void bdrv_io_plug(BlockDriverState *bs); 703 void bdrv_io_unplug(BlockDriverState *bs); 704 705 /** 706 * bdrv_parent_drained_begin_single: 707 * 708 * Begin a quiesced section for the parent of @c. If @poll is true, wait for 709 * any pending activity to cease. 710 */ 711 void bdrv_parent_drained_begin_single(BdrvChild *c, bool poll); 712 713 /** 714 * bdrv_parent_drained_end_single: 715 * 716 * End a quiesced section for the parent of @c. 717 * 718 * This polls @bs's AioContext until all scheduled sub-drained_ends 719 * have settled, which may result in graph changes. 720 */ 721 void bdrv_parent_drained_end_single(BdrvChild *c); 722 723 /** 724 * bdrv_drain_poll: 725 * 726 * Poll for pending requests in @bs, its parents (except for @ignore_parent), 727 * and if @recursive is true its children as well (used for subtree drain). 728 * 729 * If @ignore_bds_parents is true, parents that are BlockDriverStates must 730 * ignore the drain request because they will be drained separately (used for 731 * drain_all). 732 * 733 * This is part of bdrv_drained_begin. 734 */ 735 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, 736 BdrvChild *ignore_parent, bool ignore_bds_parents); 737 738 /** 739 * bdrv_drained_begin: 740 * 741 * Begin a quiesced section for exclusive access to the BDS, by disabling 742 * external request sources including NBD server and device model. Note that 743 * this doesn't block timers or coroutines from submitting more requests, which 744 * means block_job_pause is still necessary. 745 * 746 * This function can be recursive. 747 */ 748 void bdrv_drained_begin(BlockDriverState *bs); 749 750 /** 751 * bdrv_do_drained_begin_quiesce: 752 * 753 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already 754 * running requests to complete. 755 */ 756 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, 757 BdrvChild *parent, bool ignore_bds_parents); 758 759 /** 760 * Like bdrv_drained_begin, but recursively begins a quiesced section for 761 * exclusive access to all child nodes as well. 762 */ 763 void bdrv_subtree_drained_begin(BlockDriverState *bs); 764 765 /** 766 * bdrv_drained_end: 767 * 768 * End a quiescent section started by bdrv_drained_begin(). 769 * 770 * This polls @bs's AioContext until all scheduled sub-drained_ends 771 * have settled. On one hand, that may result in graph changes. On 772 * the other, this requires that the caller either runs in the main 773 * loop; or that all involved nodes (@bs and all of its parents) are 774 * in the caller's AioContext. 775 */ 776 void bdrv_drained_end(BlockDriverState *bs); 777 778 /** 779 * bdrv_drained_end_no_poll: 780 * 781 * Same as bdrv_drained_end(), but do not poll for the subgraph to 782 * actually become unquiesced. Therefore, no graph changes will occur 783 * with this function. 784 * 785 * *drained_end_counter is incremented for every background operation 786 * that is scheduled, and will be decremented for every operation once 787 * it settles. The caller must poll until it reaches 0. The counter 788 * should be accessed using atomic operations only. 789 */ 790 void bdrv_drained_end_no_poll(BlockDriverState *bs, int *drained_end_counter); 791 792 /** 793 * End a quiescent section started by bdrv_subtree_drained_begin(). 794 */ 795 void bdrv_subtree_drained_end(BlockDriverState *bs); 796 797 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 798 Error **errp); 799 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 800 801 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, 802 uint32_t granularity, Error **errp); 803 /** 804 * 805 * bdrv_register_buf/bdrv_unregister_buf: 806 * 807 * Register/unregister a buffer for I/O. For example, VFIO drivers are 808 * interested to know the memory areas that would later be used for I/O, so 809 * that they can prepare IOMMU mapping etc., to get better performance. 810 */ 811 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); 812 void bdrv_unregister_buf(BlockDriverState *bs, void *host); 813 814 /** 815 * 816 * bdrv_co_copy_range: 817 * 818 * Do offloaded copy between two children. If the operation is not implemented 819 * by the driver, or if the backend storage doesn't support it, a negative 820 * error code will be returned. 821 * 822 * Note: block layer doesn't emulate or fallback to a bounce buffer approach 823 * because usually the caller shouldn't attempt offloaded copy any more (e.g. 824 * calling copy_file_range(2)) after the first error, thus it should fall back 825 * to a read+write path in the caller level. 826 * 827 * @src: Source child to copy data from 828 * @src_offset: offset in @src image to read data 829 * @dst: Destination child to copy data to 830 * @dst_offset: offset in @dst image to write data 831 * @bytes: number of bytes to copy 832 * @flags: request flags. Supported flags: 833 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero 834 * write on @dst as if bdrv_co_pwrite_zeroes is 835 * called. Used to simplify caller code, or 836 * during BlockDriver.bdrv_co_copy_range_from() 837 * recursion. 838 * BDRV_REQ_NO_SERIALISING - do not serialize with other overlapping 839 * requests currently in flight. 840 * 841 * Returns: 0 if succeeded; negative error code if failed. 842 **/ 843 int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset, 844 BdrvChild *dst, uint64_t dst_offset, 845 uint64_t bytes, BdrvRequestFlags read_flags, 846 BdrvRequestFlags write_flags); 847 #endif 848