1 #ifndef BLOCK_H 2 #define BLOCK_H 3 4 #include "block/aio.h" 5 #include "qapi-types.h" 6 #include "qemu/iov.h" 7 #include "qemu/coroutine.h" 8 #include "block/accounting.h" 9 #include "block/dirty-bitmap.h" 10 #include "block/blockjob.h" 11 #include "qemu/hbitmap.h" 12 13 /* block.c */ 14 typedef struct BlockDriver BlockDriver; 15 typedef struct BdrvChild BdrvChild; 16 typedef struct BdrvChildRole BdrvChildRole; 17 18 typedef struct BlockDriverInfo { 19 /* in bytes, 0 if irrelevant */ 20 int cluster_size; 21 /* offset at which the VM state can be saved (0 if not possible) */ 22 int64_t vm_state_offset; 23 bool is_dirty; 24 /* 25 * True if unallocated blocks read back as zeroes. This is equivalent 26 * to the LBPRZ flag in the SCSI logical block provisioning page. 27 */ 28 bool unallocated_blocks_are_zero; 29 /* 30 * True if the driver can optimize writing zeroes by unmapping 31 * sectors. This is equivalent to the BLKDISCARDZEROES ioctl in Linux 32 * with the difference that in qemu a discard is allowed to silently 33 * fail. Therefore we have to use bdrv_pwrite_zeroes with the 34 * BDRV_REQ_MAY_UNMAP flag for an optimized zero write with unmapping. 35 * After this call the driver has to guarantee that the contents read 36 * back as zero. It is additionally required that the block device is 37 * opened with BDRV_O_UNMAP flag for this to work. 38 */ 39 bool can_write_zeroes_with_unmap; 40 /* 41 * True if this block driver only supports compressed writes 42 */ 43 bool needs_compressed_writes; 44 } BlockDriverInfo; 45 46 typedef struct BlockFragInfo { 47 uint64_t allocated_clusters; 48 uint64_t total_clusters; 49 uint64_t fragmented_clusters; 50 uint64_t compressed_clusters; 51 } BlockFragInfo; 52 53 typedef enum { 54 BDRV_REQ_COPY_ON_READ = 0x1, 55 BDRV_REQ_ZERO_WRITE = 0x2, 56 /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver 57 * is allowed to optimize a write zeroes request by unmapping (discarding) 58 * blocks if it is guaranteed that the result will read back as 59 * zeroes. The flag is only passed to the driver if the block device is 60 * opened with BDRV_O_UNMAP. 61 */ 62 BDRV_REQ_MAY_UNMAP = 0x4, 63 BDRV_REQ_NO_SERIALISING = 0x8, 64 BDRV_REQ_FUA = 0x10, 65 BDRV_REQ_WRITE_COMPRESSED = 0x20, 66 67 /* Mask of valid flags */ 68 BDRV_REQ_MASK = 0x3f, 69 } BdrvRequestFlags; 70 71 typedef struct BlockSizes { 72 uint32_t phys; 73 uint32_t log; 74 } BlockSizes; 75 76 typedef struct HDGeometry { 77 uint32_t heads; 78 uint32_t sectors; 79 uint32_t cylinders; 80 } HDGeometry; 81 82 #define BDRV_O_RDWR 0x0002 83 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */ 84 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */ 85 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */ 86 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ 87 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */ 88 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */ 89 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */ 90 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */ 91 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */ 92 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */ 93 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */ 94 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */ 95 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given: 96 select an appropriate protocol driver, 97 ignoring the format layer */ 98 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */ 99 100 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 101 102 103 /* Option names of options parsed by the block layer */ 104 105 #define BDRV_OPT_CACHE_WB "cache.writeback" 106 #define BDRV_OPT_CACHE_DIRECT "cache.direct" 107 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush" 108 #define BDRV_OPT_READ_ONLY "read-only" 109 #define BDRV_OPT_DISCARD "discard" 110 #define BDRV_OPT_FORCE_SHARE "force-share" 111 112 113 #define BDRV_SECTOR_BITS 9 114 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS) 115 #define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1) 116 117 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \ 118 INT_MAX >> BDRV_SECTOR_BITS) 119 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) 120 121 /* 122 * Allocation status flags for bdrv_block_status() and friends. 123 * 124 * Public flags: 125 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer 126 * BDRV_BLOCK_ZERO: offset reads as zero 127 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data 128 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this 129 * layer (short for DATA || ZERO), set by block layer 130 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this layer 131 * 132 * Internal flag: 133 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request 134 * that the block layer recompute the answer from the returned 135 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID. 136 * 137 * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 (BDRV_BLOCK_OFFSET_MASK) of 138 * the return value (old interface) or the entire map parameter (new 139 * interface) represent the offset in the returned BDS that is allocated for 140 * the corresponding raw data. However, whether that offset actually 141 * contains data also depends on BDRV_BLOCK_DATA, as follows: 142 * 143 * DATA ZERO OFFSET_VALID 144 * t t t sectors read as zero, returned file is zero at offset 145 * t f t sectors read as valid from file at offset 146 * f t t sectors preallocated, read as zero, returned file not 147 * necessarily zero at offset 148 * f f t sectors preallocated but read from backing_hd, 149 * returned file contains garbage at offset 150 * t t f sectors preallocated, read as zero, unknown offset 151 * t f f sectors read from unknown file or offset 152 * f t f not allocated or unknown offset, read as zero 153 * f f f not allocated or unknown offset, read from backing_hd 154 */ 155 #define BDRV_BLOCK_DATA 0x01 156 #define BDRV_BLOCK_ZERO 0x02 157 #define BDRV_BLOCK_OFFSET_VALID 0x04 158 #define BDRV_BLOCK_RAW 0x08 159 #define BDRV_BLOCK_ALLOCATED 0x10 160 #define BDRV_BLOCK_EOF 0x20 161 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK 162 163 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 164 165 typedef struct BDRVReopenState { 166 BlockDriverState *bs; 167 int flags; 168 uint64_t perm, shared_perm; 169 QDict *options; 170 QDict *explicit_options; 171 void *opaque; 172 } BDRVReopenState; 173 174 /* 175 * Block operation types 176 */ 177 typedef enum BlockOpType { 178 BLOCK_OP_TYPE_BACKUP_SOURCE, 179 BLOCK_OP_TYPE_BACKUP_TARGET, 180 BLOCK_OP_TYPE_CHANGE, 181 BLOCK_OP_TYPE_COMMIT_SOURCE, 182 BLOCK_OP_TYPE_COMMIT_TARGET, 183 BLOCK_OP_TYPE_DATAPLANE, 184 BLOCK_OP_TYPE_DRIVE_DEL, 185 BLOCK_OP_TYPE_EJECT, 186 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, 187 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, 188 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, 189 BLOCK_OP_TYPE_MIRROR_SOURCE, 190 BLOCK_OP_TYPE_MIRROR_TARGET, 191 BLOCK_OP_TYPE_RESIZE, 192 BLOCK_OP_TYPE_STREAM, 193 BLOCK_OP_TYPE_REPLACE, 194 BLOCK_OP_TYPE_MAX, 195 } BlockOpType; 196 197 /* Block node permission constants */ 198 enum { 199 /** 200 * A user that has the "permission" of consistent reads is guaranteed that 201 * their view of the contents of the block device is complete and 202 * self-consistent, representing the contents of a disk at a specific 203 * point. 204 * 205 * For most block devices (including their backing files) this is true, but 206 * the property cannot be maintained in a few situations like for 207 * intermediate nodes of a commit block job. 208 */ 209 BLK_PERM_CONSISTENT_READ = 0x01, 210 211 /** This permission is required to change the visible disk contents. */ 212 BLK_PERM_WRITE = 0x02, 213 214 /** 215 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and 216 * required for writes to the block node when the caller promises that 217 * the visible disk content doesn't change. 218 */ 219 BLK_PERM_WRITE_UNCHANGED = 0x04, 220 221 /** This permission is required to change the size of a block node. */ 222 BLK_PERM_RESIZE = 0x08, 223 224 /** 225 * This permission is required to change the node that this BdrvChild 226 * points to. 227 */ 228 BLK_PERM_GRAPH_MOD = 0x10, 229 230 BLK_PERM_ALL = 0x1f, 231 }; 232 233 char *bdrv_perm_names(uint64_t perm); 234 235 /* disk I/O throttling */ 236 void bdrv_init(void); 237 void bdrv_init_with_whitelist(void); 238 bool bdrv_uses_whitelist(void); 239 BlockDriver *bdrv_find_protocol(const char *filename, 240 bool allow_protocol_prefix, 241 Error **errp); 242 BlockDriver *bdrv_find_format(const char *format_name); 243 int bdrv_create(BlockDriver *drv, const char* filename, 244 QemuOpts *opts, Error **errp); 245 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 246 BlockDriverState *bdrv_new(void); 247 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 248 Error **errp); 249 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 250 Error **errp); 251 252 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough); 253 int bdrv_parse_discard_flags(const char *mode, int *flags); 254 BdrvChild *bdrv_open_child(const char *filename, 255 QDict *options, const char *bdref_key, 256 BlockDriverState* parent, 257 const BdrvChildRole *child_role, 258 bool allow_none, Error **errp); 259 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 260 Error **errp); 261 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 262 const char *bdref_key, Error **errp); 263 BlockDriverState *bdrv_open(const char *filename, const char *reference, 264 QDict *options, int flags, Error **errp); 265 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 266 int flags, Error **errp); 267 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 268 BlockDriverState *bs, 269 QDict *options, int flags); 270 int bdrv_reopen_multiple(AioContext *ctx, BlockReopenQueue *bs_queue, Error **errp); 271 int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp); 272 int bdrv_reopen_prepare(BDRVReopenState *reopen_state, 273 BlockReopenQueue *queue, Error **errp); 274 void bdrv_reopen_commit(BDRVReopenState *reopen_state); 275 void bdrv_reopen_abort(BDRVReopenState *reopen_state); 276 int bdrv_read(BdrvChild *child, int64_t sector_num, 277 uint8_t *buf, int nb_sectors); 278 int bdrv_write(BdrvChild *child, int64_t sector_num, 279 const uint8_t *buf, int nb_sectors); 280 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, 281 int bytes, BdrvRequestFlags flags); 282 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); 283 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes); 284 int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 285 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes); 286 int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 287 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, 288 const void *buf, int count); 289 int coroutine_fn bdrv_co_readv(BdrvChild *child, int64_t sector_num, 290 int nb_sectors, QEMUIOVector *qiov); 291 int coroutine_fn bdrv_co_writev(BdrvChild *child, int64_t sector_num, 292 int nb_sectors, QEMUIOVector *qiov); 293 /* 294 * Efficiently zero a region of the disk image. Note that this is a regular 295 * I/O request like read or write and should have a reasonable size. This 296 * function is not suitable for zeroing the entire image in a single request 297 * because it may allocate memory for the entire region. 298 */ 299 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, 300 int bytes, BdrvRequestFlags flags); 301 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 302 const char *backing_file); 303 void bdrv_refresh_filename(BlockDriverState *bs); 304 int bdrv_truncate(BdrvChild *child, int64_t offset, PreallocMode prealloc, 305 Error **errp); 306 int64_t bdrv_nb_sectors(BlockDriverState *bs); 307 int64_t bdrv_getlength(BlockDriverState *bs); 308 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); 309 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, 310 BlockDriverState *in_bs, Error **errp); 311 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr); 312 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp); 313 int bdrv_commit(BlockDriverState *bs); 314 int bdrv_change_backing_file(BlockDriverState *bs, 315 const char *backing_file, const char *backing_fmt); 316 void bdrv_register(BlockDriver *bdrv); 317 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 318 const char *backing_file_str); 319 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 320 BlockDriverState *bs); 321 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 322 323 324 typedef struct BdrvCheckResult { 325 int corruptions; 326 int leaks; 327 int check_errors; 328 int corruptions_fixed; 329 int leaks_fixed; 330 int64_t image_end_offset; 331 BlockFragInfo bfi; 332 } BdrvCheckResult; 333 334 typedef enum { 335 BDRV_FIX_LEAKS = 1, 336 BDRV_FIX_ERRORS = 2, 337 } BdrvCheckMode; 338 339 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); 340 341 /* The units of offset and total_work_size may be chosen arbitrarily by the 342 * block driver; total_work_size may change during the course of the amendment 343 * operation */ 344 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 345 int64_t total_work_size, void *opaque); 346 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 347 BlockDriverAmendStatusCB *status_cb, void *cb_opaque); 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 #define BDRV_POLL_WHILE(bs, cond) ({ \ 382 bool waited_ = false; \ 383 bool busy_ = true; \ 384 BlockDriverState *bs_ = (bs); \ 385 AioContext *ctx_ = bdrv_get_aio_context(bs_); \ 386 if (aio_context_in_iothread(ctx_)) { \ 387 while ((cond) || busy_) { \ 388 busy_ = aio_poll(ctx_, (cond)); \ 389 waited_ |= !!(cond) | busy_; \ 390 } \ 391 } else { \ 392 assert(qemu_get_current_aio_context() == \ 393 qemu_get_aio_context()); \ 394 /* Ask bdrv_dec_in_flight to wake up the main \ 395 * QEMU AioContext. Extra I/O threads never take \ 396 * other I/O threads' AioContexts (see for example \ 397 * block_job_defer_to_main_loop for how to do it). \ 398 */ \ 399 assert(!bs_->wakeup); \ 400 /* Set bs->wakeup before evaluating cond. */ \ 401 atomic_mb_set(&bs_->wakeup, true); \ 402 while (busy_) { \ 403 if ((cond)) { \ 404 waited_ = busy_ = true; \ 405 aio_context_release(ctx_); \ 406 aio_poll(qemu_get_aio_context(), true); \ 407 aio_context_acquire(ctx_); \ 408 } else { \ 409 busy_ = aio_poll(ctx_, false); \ 410 waited_ |= busy_; \ 411 } \ 412 } \ 413 atomic_set(&bs_->wakeup, false); \ 414 } \ 415 waited_; }) 416 417 int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int bytes); 418 int bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes); 419 int bdrv_has_zero_init_1(BlockDriverState *bs); 420 int bdrv_has_zero_init(BlockDriverState *bs); 421 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs); 422 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); 423 int bdrv_block_status(BlockDriverState *bs, int64_t offset, 424 int64_t bytes, int64_t *pnum, int64_t *map, 425 BlockDriverState **file); 426 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, 427 int64_t offset, int64_t bytes, int64_t *pnum, 428 int64_t *map, BlockDriverState **file); 429 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, 430 int64_t *pnum); 431 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, 432 int64_t offset, int64_t bytes, int64_t *pnum); 433 434 bool bdrv_is_read_only(BlockDriverState *bs); 435 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, 436 bool ignore_allow_rdw, Error **errp); 437 int bdrv_set_read_only(BlockDriverState *bs, bool read_only, Error **errp); 438 bool bdrv_is_sg(BlockDriverState *bs); 439 bool bdrv_is_inserted(BlockDriverState *bs); 440 void bdrv_lock_medium(BlockDriverState *bs, bool locked); 441 void bdrv_eject(BlockDriverState *bs, bool eject_flag); 442 const char *bdrv_get_format_name(BlockDriverState *bs); 443 BlockDriverState *bdrv_find_node(const char *node_name); 444 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp); 445 BlockDriverState *bdrv_lookup_bs(const char *device, 446 const char *node_name, 447 Error **errp); 448 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 449 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 450 451 typedef struct BdrvNextIterator { 452 enum { 453 BDRV_NEXT_BACKEND_ROOTS, 454 BDRV_NEXT_MONITOR_OWNED, 455 } phase; 456 BlockBackend *blk; 457 BlockDriverState *bs; 458 } BdrvNextIterator; 459 460 BlockDriverState *bdrv_first(BdrvNextIterator *it); 461 BlockDriverState *bdrv_next(BdrvNextIterator *it); 462 void bdrv_next_cleanup(BdrvNextIterator *it); 463 464 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 465 bool bdrv_is_encrypted(BlockDriverState *bs); 466 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 467 void *opaque); 468 const char *bdrv_get_node_name(const BlockDriverState *bs); 469 const char *bdrv_get_device_name(const BlockDriverState *bs); 470 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs); 471 int bdrv_get_flags(BlockDriverState *bs); 472 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); 473 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs); 474 void bdrv_round_to_clusters(BlockDriverState *bs, 475 int64_t offset, int64_t bytes, 476 int64_t *cluster_offset, 477 int64_t *cluster_bytes); 478 479 const char *bdrv_get_encrypted_filename(BlockDriverState *bs); 480 void bdrv_get_backing_filename(BlockDriverState *bs, 481 char *filename, int filename_size); 482 void bdrv_get_full_backing_filename(BlockDriverState *bs, 483 char *dest, size_t sz, Error **errp); 484 void bdrv_get_full_backing_filename_from_filename(const char *backed, 485 const char *backing, 486 char *dest, size_t sz, 487 Error **errp); 488 489 int path_has_protocol(const char *path); 490 int path_is_absolute(const char *path); 491 void path_combine(char *dest, int dest_size, 492 const char *base_path, 493 const char *filename); 494 495 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 496 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 497 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 498 int64_t pos, int size); 499 500 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 501 int64_t pos, int size); 502 503 void bdrv_img_create(const char *filename, const char *fmt, 504 const char *base_filename, const char *base_fmt, 505 char *options, uint64_t img_size, int flags, 506 bool quiet, Error **errp); 507 508 /* Returns the alignment in bytes that is required so that no bounce buffer 509 * is required throughout the stack */ 510 size_t bdrv_min_mem_align(BlockDriverState *bs); 511 /* Returns optimal alignment in bytes for bounce buffer */ 512 size_t bdrv_opt_mem_align(BlockDriverState *bs); 513 void *qemu_blockalign(BlockDriverState *bs, size_t size); 514 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 515 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 516 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 517 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 518 519 void bdrv_enable_copy_on_read(BlockDriverState *bs); 520 void bdrv_disable_copy_on_read(BlockDriverState *bs); 521 522 void bdrv_ref(BlockDriverState *bs); 523 void bdrv_unref(BlockDriverState *bs); 524 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 525 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 526 BlockDriverState *child_bs, 527 const char *child_name, 528 const BdrvChildRole *child_role, 529 Error **errp); 530 531 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 532 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 533 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 534 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 535 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 536 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 537 538 #define BLKDBG_EVENT(child, evt) \ 539 do { \ 540 if (child) { \ 541 bdrv_debug_event(child->bs, evt); \ 542 } \ 543 } while (0) 544 545 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 546 547 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 548 const char *tag); 549 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 550 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 551 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 552 553 /** 554 * bdrv_get_aio_context: 555 * 556 * Returns: the currently bound #AioContext 557 */ 558 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 559 560 /** 561 * Transfer control to @co in the aio context of @bs 562 */ 563 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 564 565 /** 566 * bdrv_set_aio_context: 567 * 568 * Changes the #AioContext used for fd handlers, timers, and BHs by this 569 * BlockDriverState and all its children. 570 * 571 * This function must be called with iothread lock held. 572 */ 573 void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context); 574 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 575 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 576 577 void bdrv_io_plug(BlockDriverState *bs); 578 void bdrv_io_unplug(BlockDriverState *bs); 579 580 /** 581 * bdrv_parent_drained_begin: 582 * 583 * Begin a quiesced section of all users of @bs. This is part of 584 * bdrv_drained_begin. 585 */ 586 void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore); 587 588 /** 589 * bdrv_parent_drained_end: 590 * 591 * End a quiesced section of all users of @bs. This is part of 592 * bdrv_drained_end. 593 */ 594 void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore); 595 596 /** 597 * bdrv_drained_begin: 598 * 599 * Begin a quiesced section for exclusive access to the BDS, by disabling 600 * external request sources including NBD server and device model. Note that 601 * this doesn't block timers or coroutines from submitting more requests, which 602 * means block_job_pause is still necessary. 603 * 604 * This function can be recursive. 605 */ 606 void bdrv_drained_begin(BlockDriverState *bs); 607 608 /** 609 * Like bdrv_drained_begin, but recursively begins a quiesced section for 610 * exclusive access to all child nodes as well. 611 */ 612 void bdrv_subtree_drained_begin(BlockDriverState *bs); 613 614 /** 615 * bdrv_drained_end: 616 * 617 * End a quiescent section started by bdrv_drained_begin(). 618 */ 619 void bdrv_drained_end(BlockDriverState *bs); 620 621 /** 622 * End a quiescent section started by bdrv_subtree_drained_begin(). 623 */ 624 void bdrv_subtree_drained_end(BlockDriverState *bs); 625 626 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 627 Error **errp); 628 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 629 630 bool bdrv_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, 631 uint32_t granularity, Error **errp); 632 /** 633 * 634 * bdrv_register_buf/bdrv_unregister_buf: 635 * 636 * Register/unregister a buffer for I/O. For example, VFIO drivers are 637 * interested to know the memory areas that would later be used for I/O, so 638 * that they can prepare IOMMU mapping etc., to get better performance. 639 */ 640 void bdrv_register_buf(BlockDriverState *bs, void *host, size_t size); 641 void bdrv_unregister_buf(BlockDriverState *bs, void *host); 642 #endif 643