1 #ifndef BLOCK_H 2 #define BLOCK_H 3 4 #include "block/aio.h" 5 #include "qapi/qapi-types-block-core.h" 6 #include "block/aio-wait.h" 7 #include "qemu/iov.h" 8 #include "qemu/coroutine.h" 9 #include "block/accounting.h" 10 #include "block/dirty-bitmap.h" 11 #include "block/blockjob.h" 12 #include "qemu/hbitmap.h" 13 14 /* block.c */ 15 typedef struct BlockDriver BlockDriver; 16 typedef struct BdrvChild BdrvChild; 17 typedef struct BdrvChildRole BdrvChildRole; 18 19 typedef struct BlockDriverInfo { 20 /* in bytes, 0 if irrelevant */ 21 int cluster_size; 22 /* offset at which the VM state can be saved (0 if not possible) */ 23 int64_t vm_state_offset; 24 bool is_dirty; 25 /* 26 * True if unallocated blocks read back as zeroes. This is equivalent 27 * to the LBPRZ flag in the SCSI logical block provisioning page. 28 */ 29 bool unallocated_blocks_are_zero; 30 /* 31 * True if this block driver only supports compressed writes 32 */ 33 bool needs_compressed_writes; 34 } BlockDriverInfo; 35 36 typedef struct BlockFragInfo { 37 uint64_t allocated_clusters; 38 uint64_t total_clusters; 39 uint64_t fragmented_clusters; 40 uint64_t compressed_clusters; 41 } BlockFragInfo; 42 43 typedef enum { 44 BDRV_REQ_COPY_ON_READ = 0x1, 45 BDRV_REQ_ZERO_WRITE = 0x2, 46 /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver 47 * is allowed to optimize a write zeroes request by unmapping (discarding) 48 * blocks if it is guaranteed that the result will read back as 49 * zeroes. The flag is only passed to the driver if the block device is 50 * opened with BDRV_O_UNMAP. 51 */ 52 BDRV_REQ_MAY_UNMAP = 0x4, 53 BDRV_REQ_NO_SERIALISING = 0x8, 54 BDRV_REQ_FUA = 0x10, 55 BDRV_REQ_WRITE_COMPRESSED = 0x20, 56 57 /* Signifies that this write request will not change the visible disk 58 * content. */ 59 BDRV_REQ_WRITE_UNCHANGED = 0x40, 60 61 /* Mask of valid flags */ 62 BDRV_REQ_MASK = 0x7f, 63 } BdrvRequestFlags; 64 65 typedef struct BlockSizes { 66 uint32_t phys; 67 uint32_t log; 68 } BlockSizes; 69 70 typedef struct HDGeometry { 71 uint32_t heads; 72 uint32_t sectors; 73 uint32_t cylinders; 74 } HDGeometry; 75 76 #define BDRV_O_RDWR 0x0002 77 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */ 78 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */ 79 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */ 80 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ 81 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */ 82 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */ 83 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */ 84 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */ 85 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */ 86 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */ 87 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */ 88 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */ 89 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given: 90 select an appropriate protocol driver, 91 ignoring the format layer */ 92 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */ 93 94 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 95 96 97 /* Option names of options parsed by the block layer */ 98 99 #define BDRV_OPT_CACHE_WB "cache.writeback" 100 #define BDRV_OPT_CACHE_DIRECT "cache.direct" 101 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush" 102 #define BDRV_OPT_READ_ONLY "read-only" 103 #define BDRV_OPT_DISCARD "discard" 104 #define BDRV_OPT_FORCE_SHARE "force-share" 105 106 107 #define BDRV_SECTOR_BITS 9 108 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS) 109 #define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1) 110 111 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \ 112 INT_MAX >> BDRV_SECTOR_BITS) 113 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) 114 115 /* 116 * Allocation status flags for bdrv_block_status() and friends. 117 * 118 * Public flags: 119 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer 120 * BDRV_BLOCK_ZERO: offset reads as zero 121 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data 122 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this 123 * layer rather than any backing, set by block layer 124 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this 125 * layer, set by block layer 126 * 127 * Internal flag: 128 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request 129 * that the block layer recompute the answer from the returned 130 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID. 131 * 132 * If BDRV_BLOCK_OFFSET_VALID is set, the map parameter represents the 133 * host offset within the returned BDS that is allocated for the 134 * corresponding raw guest data. However, whether that offset 135 * actually contains data also depends on BDRV_BLOCK_DATA, as follows: 136 * 137 * DATA ZERO OFFSET_VALID 138 * t t t sectors read as zero, returned file is zero at offset 139 * t f t sectors read as valid from file at offset 140 * f t t sectors preallocated, read as zero, returned file not 141 * necessarily zero at offset 142 * f f t sectors preallocated but read from backing_hd, 143 * returned file contains garbage at offset 144 * t t f sectors preallocated, read as zero, unknown offset 145 * t f f sectors read from unknown file or offset 146 * f t f not allocated or unknown offset, read as zero 147 * f f f not allocated or unknown offset, read from backing_hd 148 */ 149 #define BDRV_BLOCK_DATA 0x01 150 #define BDRV_BLOCK_ZERO 0x02 151 #define BDRV_BLOCK_OFFSET_VALID 0x04 152 #define BDRV_BLOCK_RAW 0x08 153 #define BDRV_BLOCK_ALLOCATED 0x10 154 #define BDRV_BLOCK_EOF 0x20 155 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK 156 157 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 158 159 typedef struct BDRVReopenState { 160 BlockDriverState *bs; 161 int flags; 162 uint64_t perm, shared_perm; 163 QDict *options; 164 QDict *explicit_options; 165 void *opaque; 166 } BDRVReopenState; 167 168 /* 169 * Block operation types 170 */ 171 typedef enum BlockOpType { 172 BLOCK_OP_TYPE_BACKUP_SOURCE, 173 BLOCK_OP_TYPE_BACKUP_TARGET, 174 BLOCK_OP_TYPE_CHANGE, 175 BLOCK_OP_TYPE_COMMIT_SOURCE, 176 BLOCK_OP_TYPE_COMMIT_TARGET, 177 BLOCK_OP_TYPE_DATAPLANE, 178 BLOCK_OP_TYPE_DRIVE_DEL, 179 BLOCK_OP_TYPE_EJECT, 180 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, 181 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, 182 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, 183 BLOCK_OP_TYPE_MIRROR_SOURCE, 184 BLOCK_OP_TYPE_MIRROR_TARGET, 185 BLOCK_OP_TYPE_RESIZE, 186 BLOCK_OP_TYPE_STREAM, 187 BLOCK_OP_TYPE_REPLACE, 188 BLOCK_OP_TYPE_MAX, 189 } BlockOpType; 190 191 /* Block node permission constants */ 192 enum { 193 /** 194 * A user that has the "permission" of consistent reads is guaranteed that 195 * their view of the contents of the block device is complete and 196 * self-consistent, representing the contents of a disk at a specific 197 * point. 198 * 199 * For most block devices (including their backing files) this is true, but 200 * the property cannot be maintained in a few situations like for 201 * intermediate nodes of a commit block job. 202 */ 203 BLK_PERM_CONSISTENT_READ = 0x01, 204 205 /** This permission is required to change the visible disk contents. */ 206 BLK_PERM_WRITE = 0x02, 207 208 /** 209 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and 210 * required for writes to the block node when the caller promises that 211 * the visible disk content doesn't change. 212 * 213 * As the BLK_PERM_WRITE permission is strictly stronger, either is 214 * sufficient to perform an unchanging write. 215 */ 216 BLK_PERM_WRITE_UNCHANGED = 0x04, 217 218 /** This permission is required to change the size of a block node. */ 219 BLK_PERM_RESIZE = 0x08, 220 221 /** 222 * This permission is required to change the node that this BdrvChild 223 * points to. 224 */ 225 BLK_PERM_GRAPH_MOD = 0x10, 226 227 BLK_PERM_ALL = 0x1f, 228 }; 229 230 char *bdrv_perm_names(uint64_t perm); 231 232 /* disk I/O throttling */ 233 void bdrv_init(void); 234 void bdrv_init_with_whitelist(void); 235 bool bdrv_uses_whitelist(void); 236 int bdrv_is_whitelisted(BlockDriver *drv, bool read_only); 237 BlockDriver *bdrv_find_protocol(const char *filename, 238 bool allow_protocol_prefix, 239 Error **errp); 240 BlockDriver *bdrv_find_format(const char *format_name); 241 int bdrv_create(BlockDriver *drv, const char* filename, 242 QemuOpts *opts, Error **errp); 243 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 244 BlockDriverState *bdrv_new(void); 245 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 246 Error **errp); 247 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 248 Error **errp); 249 250 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough); 251 int bdrv_parse_discard_flags(const char *mode, int *flags); 252 BdrvChild *bdrv_open_child(const char *filename, 253 QDict *options, const char *bdref_key, 254 BlockDriverState* parent, 255 const BdrvChildRole *child_role, 256 bool allow_none, Error **errp); 257 BlockDriverState *bdrv_open_blockdev_ref(BlockdevRef *ref, Error **errp); 258 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 259 Error **errp); 260 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 261 const char *bdref_key, Error **errp); 262 BlockDriverState *bdrv_open(const char *filename, const char *reference, 263 QDict *options, int flags, Error **errp); 264 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 265 int flags, Error **errp); 266 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 267 BlockDriverState *bs, 268 QDict *options, int flags); 269 int bdrv_reopen_multiple(AioContext *ctx, BlockReopenQueue *bs_queue, Error **errp); 270 int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp); 271 int bdrv_reopen_prepare(BDRVReopenState *reopen_state, 272 BlockReopenQueue *queue, Error **errp); 273 void bdrv_reopen_commit(BDRVReopenState *reopen_state); 274 void bdrv_reopen_abort(BDRVReopenState *reopen_state); 275 int bdrv_read(BdrvChild *child, int64_t sector_num, 276 uint8_t *buf, int nb_sectors); 277 int bdrv_write(BdrvChild *child, int64_t sector_num, 278 const uint8_t *buf, int nb_sectors); 279 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, 280 int bytes, BdrvRequestFlags flags); 281 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); 282 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes); 283 int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 284 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes); 285 int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 286 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, 287 const void *buf, int count); 288 int coroutine_fn bdrv_co_readv(BdrvChild *child, int64_t sector_num, 289 int nb_sectors, QEMUIOVector *qiov); 290 int coroutine_fn bdrv_co_writev(BdrvChild *child, int64_t sector_num, 291 int nb_sectors, QEMUIOVector *qiov); 292 /* 293 * Efficiently zero a region of the disk image. Note that this is a regular 294 * I/O request like read or write and should have a reasonable size. This 295 * function is not suitable for zeroing the entire image in a single request 296 * because it may allocate memory for the entire region. 297 */ 298 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, 299 int bytes, BdrvRequestFlags flags); 300 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 301 const char *backing_file); 302 void bdrv_refresh_filename(BlockDriverState *bs); 303 int bdrv_truncate(BdrvChild *child, int64_t offset, PreallocMode prealloc, 304 Error **errp); 305 int64_t bdrv_nb_sectors(BlockDriverState *bs); 306 int64_t bdrv_getlength(BlockDriverState *bs); 307 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); 308 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, 309 BlockDriverState *in_bs, Error **errp); 310 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr); 311 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp); 312 int bdrv_commit(BlockDriverState *bs); 313 int bdrv_change_backing_file(BlockDriverState *bs, 314 const char *backing_file, const char *backing_fmt); 315 void bdrv_register(BlockDriver *bdrv); 316 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 317 const char *backing_file_str); 318 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 319 BlockDriverState *bs); 320 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 321 322 323 typedef struct BdrvCheckResult { 324 int corruptions; 325 int leaks; 326 int check_errors; 327 int corruptions_fixed; 328 int leaks_fixed; 329 int64_t image_end_offset; 330 BlockFragInfo bfi; 331 } BdrvCheckResult; 332 333 typedef enum { 334 BDRV_FIX_LEAKS = 1, 335 BDRV_FIX_ERRORS = 2, 336 } BdrvCheckMode; 337 338 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); 339 340 /* The units of offset and total_work_size may be chosen arbitrarily by the 341 * block driver; total_work_size may change during the course of the amendment 342 * operation */ 343 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 344 int64_t total_work_size, void *opaque); 345 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 346 BlockDriverAmendStatusCB *status_cb, void *cb_opaque, 347 Error **errp); 348 349 /* external snapshots */ 350 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs, 351 BlockDriverState *candidate); 352 bool bdrv_is_first_non_filter(BlockDriverState *candidate); 353 354 /* check if a named node can be replaced when doing drive-mirror */ 355 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 356 const char *node_name, Error **errp); 357 358 /* async block I/O */ 359 void bdrv_aio_cancel(BlockAIOCB *acb); 360 void bdrv_aio_cancel_async(BlockAIOCB *acb); 361 362 /* sg packet commands */ 363 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 364 365 /* Invalidate any cached metadata used by image formats */ 366 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp); 367 void bdrv_invalidate_cache_all(Error **errp); 368 int bdrv_inactivate_all(void); 369 370 /* Ensure contents are flushed to disk. */ 371 int bdrv_flush(BlockDriverState *bs); 372 int coroutine_fn bdrv_co_flush(BlockDriverState *bs); 373 int bdrv_flush_all(void); 374 void bdrv_close_all(void); 375 void bdrv_drain(BlockDriverState *bs); 376 void coroutine_fn bdrv_co_drain(BlockDriverState *bs); 377 void bdrv_drain_all_begin(void); 378 void bdrv_drain_all_end(void); 379 void bdrv_drain_all(void); 380 381 /* Returns NULL when bs == NULL */ 382 AioWait *bdrv_get_aio_wait(BlockDriverState *bs); 383 384 #define BDRV_POLL_WHILE(bs, cond) ({ \ 385 BlockDriverState *bs_ = (bs); \ 386 AIO_WAIT_WHILE(bdrv_get_aio_wait(bs_), \ 387 bdrv_get_aio_context(bs_), \ 388 cond); }) 389 390 int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int bytes); 391 int bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes); 392 int bdrv_has_zero_init_1(BlockDriverState *bs); 393 int bdrv_has_zero_init(BlockDriverState *bs); 394 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs); 395 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); 396 int bdrv_block_status(BlockDriverState *bs, int64_t offset, 397 int64_t bytes, int64_t *pnum, int64_t *map, 398 BlockDriverState **file); 399 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, 400 int64_t offset, int64_t bytes, int64_t *pnum, 401 int64_t *map, BlockDriverState **file); 402 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, 403 int64_t *pnum); 404 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, 405 int64_t offset, int64_t bytes, int64_t *pnum); 406 407 bool bdrv_is_read_only(BlockDriverState *bs); 408 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, 409 bool ignore_allow_rdw, Error **errp); 410 int bdrv_set_read_only(BlockDriverState *bs, bool read_only, Error **errp); 411 bool bdrv_is_writable(BlockDriverState *bs); 412 bool bdrv_is_sg(BlockDriverState *bs); 413 bool bdrv_is_inserted(BlockDriverState *bs); 414 void bdrv_lock_medium(BlockDriverState *bs, bool locked); 415 void bdrv_eject(BlockDriverState *bs, bool eject_flag); 416 const char *bdrv_get_format_name(BlockDriverState *bs); 417 BlockDriverState *bdrv_find_node(const char *node_name); 418 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp); 419 BlockDriverState *bdrv_lookup_bs(const char *device, 420 const char *node_name, 421 Error **errp); 422 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 423 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 424 BlockDriverState *bdrv_next_all_states(BlockDriverState *bs); 425 426 typedef struct BdrvNextIterator { 427 enum { 428 BDRV_NEXT_BACKEND_ROOTS, 429 BDRV_NEXT_MONITOR_OWNED, 430 } phase; 431 BlockBackend *blk; 432 BlockDriverState *bs; 433 } BdrvNextIterator; 434 435 BlockDriverState *bdrv_first(BdrvNextIterator *it); 436 BlockDriverState *bdrv_next(BdrvNextIterator *it); 437 void bdrv_next_cleanup(BdrvNextIterator *it); 438 439 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 440 bool bdrv_is_encrypted(BlockDriverState *bs); 441 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 442 void *opaque); 443 const char *bdrv_get_node_name(const BlockDriverState *bs); 444 const char *bdrv_get_device_name(const BlockDriverState *bs); 445 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs); 446 int bdrv_get_flags(BlockDriverState *bs); 447 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); 448 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs); 449 void bdrv_round_to_clusters(BlockDriverState *bs, 450 int64_t offset, int64_t bytes, 451 int64_t *cluster_offset, 452 int64_t *cluster_bytes); 453 454 const char *bdrv_get_encrypted_filename(BlockDriverState *bs); 455 void bdrv_get_backing_filename(BlockDriverState *bs, 456 char *filename, int filename_size); 457 void bdrv_get_full_backing_filename(BlockDriverState *bs, 458 char *dest, size_t sz, Error **errp); 459 void bdrv_get_full_backing_filename_from_filename(const char *backed, 460 const char *backing, 461 char *dest, size_t sz, 462 Error **errp); 463 464 int path_has_protocol(const char *path); 465 int path_is_absolute(const char *path); 466 void path_combine(char *dest, int dest_size, 467 const char *base_path, 468 const char *filename); 469 470 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 471 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 472 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 473 int64_t pos, int size); 474 475 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 476 int64_t pos, int size); 477 478 void bdrv_img_create(const char *filename, const char *fmt, 479 const char *base_filename, const char *base_fmt, 480 char *options, uint64_t img_size, int flags, 481 bool quiet, Error **errp); 482 483 /* Returns the alignment in bytes that is required so that no bounce buffer 484 * is required throughout the stack */ 485 size_t bdrv_min_mem_align(BlockDriverState *bs); 486 /* Returns optimal alignment in bytes for bounce buffer */ 487 size_t bdrv_opt_mem_align(BlockDriverState *bs); 488 void *qemu_blockalign(BlockDriverState *bs, size_t size); 489 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 490 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 491 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 492 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 493 494 void bdrv_enable_copy_on_read(BlockDriverState *bs); 495 void bdrv_disable_copy_on_read(BlockDriverState *bs); 496 497 void bdrv_ref(BlockDriverState *bs); 498 void bdrv_unref(BlockDriverState *bs); 499 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 500 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 501 BlockDriverState *child_bs, 502 const char *child_name, 503 const BdrvChildRole *child_role, 504 Error **errp); 505 506 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 507 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 508 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 509 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 510 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 511 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 512 513 #define BLKDBG_EVENT(child, evt) \ 514 do { \ 515 if (child) { \ 516 bdrv_debug_event(child->bs, evt); \ 517 } \ 518 } while (0) 519 520 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 521 522 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 523 const char *tag); 524 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 525 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 526 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 527 528 /** 529 * bdrv_get_aio_context: 530 * 531 * Returns: the currently bound #AioContext 532 */ 533 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 534 535 /** 536 * Transfer control to @co in the aio context of @bs 537 */ 538 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 539 540 /** 541 * bdrv_set_aio_context: 542 * 543 * Changes the #AioContext used for fd handlers, timers, and BHs by this 544 * BlockDriverState and all its children. 545 * 546 * This function must be called with iothread lock held. 547 */ 548 void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context); 549 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 550 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 551 552 void bdrv_io_plug(BlockDriverState *bs); 553 void bdrv_io_unplug(BlockDriverState *bs); 554 555 /** 556 * bdrv_parent_drained_begin: 557 * 558 * Begin a quiesced section of all users of @bs. This is part of 559 * bdrv_drained_begin. 560 */ 561 void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore, 562 bool ignore_bds_parents); 563 564 /** 565 * bdrv_parent_drained_end: 566 * 567 * End a quiesced section of all users of @bs. This is part of 568 * bdrv_drained_end. 569 */ 570 void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore, 571 bool ignore_bds_parents); 572 573 /** 574 * bdrv_drain_poll: 575 * 576 * Poll for pending requests in @bs, its parents (except for @ignore_parent), 577 * and if @recursive is true its children as well (used for subtree drain). 578 * 579 * If @ignore_bds_parents is true, parents that are BlockDriverStates must 580 * ignore the drain request because they will be drained separately (used for 581 * drain_all). 582 * 583 * This is part of bdrv_drained_begin. 584 */ 585 bool bdrv_drain_poll(BlockDriverState *bs, bool recursive, 586 BdrvChild *ignore_parent, bool ignore_bds_parents); 587 588 /** 589 * bdrv_drained_begin: 590 * 591 * Begin a quiesced section for exclusive access to the BDS, by disabling 592 * external request sources including NBD server and device model. Note that 593 * this doesn't block timers or coroutines from submitting more requests, which 594 * means block_job_pause is still necessary. 595 * 596 * This function can be recursive. 597 */ 598 void bdrv_drained_begin(BlockDriverState *bs); 599 600 /** 601 * bdrv_do_drained_begin_quiesce: 602 * 603 * Quiesces a BDS like bdrv_drained_begin(), but does not wait for already 604 * running requests to complete. 605 */ 606 void bdrv_do_drained_begin_quiesce(BlockDriverState *bs, 607 BdrvChild *parent, bool ignore_bds_parents); 608 609 /** 610 * Like bdrv_drained_begin, but recursively begins a quiesced section for 611 * exclusive access to all child nodes as well. 612 */ 613 void bdrv_subtree_drained_begin(BlockDriverState *bs); 614 615 /** 616 * bdrv_drained_end: 617 * 618 * End a quiescent section started by bdrv_drained_begin(). 619 */ 620 void bdrv_drained_end(BlockDriverState *bs); 621 622 /** 623 * End a quiescent section started by bdrv_subtree_drained_begin(). 624 */ 625 void bdrv_subtree_drained_end(BlockDriverState *bs); 626 627 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 628 Error **errp); 629 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 630 631 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, 632 uint32_t granularity, Error **errp); 633 /** 634 * 635 * bdrv_register_buf/bdrv_unregister_buf: 636 * 637 * Register/unregister a buffer for I/O. For example, VFIO drivers are 638 * interested to know the memory areas that would later be used for I/O, so 639 * that they can prepare IOMMU mapping etc., to get better performance. 640 */ 641 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); 642 void bdrv_unregister_buf(BlockDriverState *bs, void *host); 643 644 /** 645 * 646 * bdrv_co_copy_range: 647 * 648 * Do offloaded copy between two children. If the operation is not implemented 649 * by the driver, or if the backend storage doesn't support it, a negative 650 * error code will be returned. 651 * 652 * Note: block layer doesn't emulate or fallback to a bounce buffer approach 653 * because usually the caller shouldn't attempt offloaded copy any more (e.g. 654 * calling copy_file_range(2)) after the first error, thus it should fall back 655 * to a read+write path in the caller level. 656 * 657 * @src: Source child to copy data from 658 * @src_offset: offset in @src image to read data 659 * @dst: Destination child to copy data to 660 * @dst_offset: offset in @dst image to write data 661 * @bytes: number of bytes to copy 662 * @flags: request flags. Must be one of: 663 * 0 - actually read data from src; 664 * BDRV_REQ_ZERO_WRITE - treat the @src range as zero data and do zero 665 * write on @dst as if bdrv_co_pwrite_zeroes is 666 * called. Used to simplify caller code, or 667 * during BlockDriver.bdrv_co_copy_range_from() 668 * recursion. 669 * 670 * Returns: 0 if succeeded; negative error code if failed. 671 **/ 672 int coroutine_fn bdrv_co_copy_range(BdrvChild *src, uint64_t src_offset, 673 BdrvChild *dst, uint64_t dst_offset, 674 uint64_t bytes, BdrvRequestFlags flags); 675 #endif 676