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