1 #ifndef BLOCK_H 2 #define BLOCK_H 3 4 #include "block/aio.h" 5 #include "qemu/iov.h" 6 #include "qemu/option.h" 7 #include "qemu/coroutine.h" 8 #include "block/accounting.h" 9 #include "block/dirty-bitmap.h" 10 #include "block/blockjob.h" 11 #include "qapi/qmp/qobject.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 the driver can optimize writing zeroes by unmapping 32 * sectors. This is equivalent to the BLKDISCARDZEROES ioctl in Linux 33 * with the difference that in qemu a discard is allowed to silently 34 * fail. Therefore we have to use bdrv_pwrite_zeroes with the 35 * BDRV_REQ_MAY_UNMAP flag for an optimized zero write with unmapping. 36 * After this call the driver has to guarantee that the contents read 37 * back as zero. It is additionally required that the block device is 38 * opened with BDRV_O_UNMAP flag for this to work. 39 */ 40 bool can_write_zeroes_with_unmap; 41 /* 42 * True if this block driver only supports compressed writes 43 */ 44 bool needs_compressed_writes; 45 } BlockDriverInfo; 46 47 typedef struct BlockFragInfo { 48 uint64_t allocated_clusters; 49 uint64_t total_clusters; 50 uint64_t fragmented_clusters; 51 uint64_t compressed_clusters; 52 } BlockFragInfo; 53 54 typedef enum { 55 BDRV_REQ_COPY_ON_READ = 0x1, 56 BDRV_REQ_ZERO_WRITE = 0x2, 57 /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver 58 * is allowed to optimize a write zeroes request by unmapping (discarding) 59 * blocks if it is guaranteed that the result will read back as 60 * zeroes. The flag is only passed to the driver if the block device is 61 * opened with BDRV_O_UNMAP. 62 */ 63 BDRV_REQ_MAY_UNMAP = 0x4, 64 BDRV_REQ_NO_SERIALISING = 0x8, 65 BDRV_REQ_FUA = 0x10, 66 BDRV_REQ_WRITE_COMPRESSED = 0x20, 67 68 /* Mask of valid flags */ 69 BDRV_REQ_MASK = 0x3f, 70 } BdrvRequestFlags; 71 72 typedef struct BlockSizes { 73 uint32_t phys; 74 uint32_t log; 75 } BlockSizes; 76 77 typedef struct HDGeometry { 78 uint32_t heads; 79 uint32_t sectors; 80 uint32_t cylinders; 81 } HDGeometry; 82 83 #define BDRV_O_RDWR 0x0002 84 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */ 85 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */ 86 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */ 87 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ 88 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */ 89 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */ 90 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */ 91 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */ 92 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */ 93 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */ 94 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */ 95 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */ 96 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given: 97 select an appropriate protocol driver, 98 ignoring the format layer */ 99 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */ 100 101 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 102 103 104 /* Option names of options parsed by the block layer */ 105 106 #define BDRV_OPT_CACHE_WB "cache.writeback" 107 #define BDRV_OPT_CACHE_DIRECT "cache.direct" 108 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush" 109 #define BDRV_OPT_READ_ONLY "read-only" 110 #define BDRV_OPT_DISCARD "discard" 111 #define BDRV_OPT_FORCE_SHARE "force-share" 112 113 114 #define BDRV_SECTOR_BITS 9 115 #define BDRV_SECTOR_SIZE (1ULL << BDRV_SECTOR_BITS) 116 #define BDRV_SECTOR_MASK ~(BDRV_SECTOR_SIZE - 1) 117 118 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \ 119 INT_MAX >> BDRV_SECTOR_BITS) 120 #define BDRV_REQUEST_MAX_BYTES (BDRV_REQUEST_MAX_SECTORS << BDRV_SECTOR_BITS) 121 122 /* 123 * Allocation status flags for bdrv_block_status() and friends. 124 * 125 * Public flags: 126 * BDRV_BLOCK_DATA: allocation for data at offset is tied to this layer 127 * BDRV_BLOCK_ZERO: offset reads as zero 128 * BDRV_BLOCK_OFFSET_VALID: an associated offset exists for accessing raw data 129 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this 130 * layer (short for DATA || ZERO), set by block layer 131 * BDRV_BLOCK_EOF: the returned pnum covers through end of file for this layer 132 * 133 * Internal flag: 134 * BDRV_BLOCK_RAW: for use by passthrough drivers, such as raw, to request 135 * that the block layer recompute the answer from the returned 136 * BDS; must be accompanied by just BDRV_BLOCK_OFFSET_VALID. 137 * 138 * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 (BDRV_BLOCK_OFFSET_MASK) of 139 * the return value (old interface) or the entire map parameter (new 140 * interface) represent the offset in the returned BDS that is allocated for 141 * the corresponding raw data. However, whether that offset actually 142 * contains data also depends on BDRV_BLOCK_DATA, as follows: 143 * 144 * DATA ZERO OFFSET_VALID 145 * t t t sectors read as zero, returned file is zero at offset 146 * t f t sectors read as valid from file at offset 147 * f t t sectors preallocated, read as zero, returned file not 148 * necessarily zero at offset 149 * f f t sectors preallocated but read from backing_hd, 150 * returned file contains garbage at offset 151 * t t f sectors preallocated, read as zero, unknown offset 152 * t f f sectors read from unknown file or offset 153 * f t f not allocated or unknown offset, read as zero 154 * f f f not allocated or unknown offset, read from backing_hd 155 */ 156 #define BDRV_BLOCK_DATA 0x01 157 #define BDRV_BLOCK_ZERO 0x02 158 #define BDRV_BLOCK_OFFSET_VALID 0x04 159 #define BDRV_BLOCK_RAW 0x08 160 #define BDRV_BLOCK_ALLOCATED 0x10 161 #define BDRV_BLOCK_EOF 0x20 162 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK 163 164 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 165 166 typedef struct BDRVReopenState { 167 BlockDriverState *bs; 168 int flags; 169 uint64_t perm, shared_perm; 170 QDict *options; 171 QDict *explicit_options; 172 void *opaque; 173 } BDRVReopenState; 174 175 /* 176 * Block operation types 177 */ 178 typedef enum BlockOpType { 179 BLOCK_OP_TYPE_BACKUP_SOURCE, 180 BLOCK_OP_TYPE_BACKUP_TARGET, 181 BLOCK_OP_TYPE_CHANGE, 182 BLOCK_OP_TYPE_COMMIT_SOURCE, 183 BLOCK_OP_TYPE_COMMIT_TARGET, 184 BLOCK_OP_TYPE_DATAPLANE, 185 BLOCK_OP_TYPE_DRIVE_DEL, 186 BLOCK_OP_TYPE_EJECT, 187 BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT, 188 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT, 189 BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE, 190 BLOCK_OP_TYPE_MIRROR_SOURCE, 191 BLOCK_OP_TYPE_MIRROR_TARGET, 192 BLOCK_OP_TYPE_RESIZE, 193 BLOCK_OP_TYPE_STREAM, 194 BLOCK_OP_TYPE_REPLACE, 195 BLOCK_OP_TYPE_MAX, 196 } BlockOpType; 197 198 /* Block node permission constants */ 199 enum { 200 /** 201 * A user that has the "permission" of consistent reads is guaranteed that 202 * their view of the contents of the block device is complete and 203 * self-consistent, representing the contents of a disk at a specific 204 * point. 205 * 206 * For most block devices (including their backing files) this is true, but 207 * the property cannot be maintained in a few situations like for 208 * intermediate nodes of a commit block job. 209 */ 210 BLK_PERM_CONSISTENT_READ = 0x01, 211 212 /** This permission is required to change the visible disk contents. */ 213 BLK_PERM_WRITE = 0x02, 214 215 /** 216 * This permission (which is weaker than BLK_PERM_WRITE) is both enough and 217 * required for writes to the block node when the caller promises that 218 * the visible disk content doesn't change. 219 */ 220 BLK_PERM_WRITE_UNCHANGED = 0x04, 221 222 /** This permission is required to change the size of a block node. */ 223 BLK_PERM_RESIZE = 0x08, 224 225 /** 226 * This permission is required to change the node that this BdrvChild 227 * points to. 228 */ 229 BLK_PERM_GRAPH_MOD = 0x10, 230 231 BLK_PERM_ALL = 0x1f, 232 }; 233 234 char *bdrv_perm_names(uint64_t perm); 235 236 /* disk I/O throttling */ 237 void bdrv_init(void); 238 void bdrv_init_with_whitelist(void); 239 bool bdrv_uses_whitelist(void); 240 BlockDriver *bdrv_find_protocol(const char *filename, 241 bool allow_protocol_prefix, 242 Error **errp); 243 BlockDriver *bdrv_find_format(const char *format_name); 244 int bdrv_create(BlockDriver *drv, const char* filename, 245 QemuOpts *opts, Error **errp); 246 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 247 BlockDriverState *bdrv_new(void); 248 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 249 Error **errp); 250 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 251 Error **errp); 252 253 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough); 254 int bdrv_parse_discard_flags(const char *mode, int *flags); 255 BdrvChild *bdrv_open_child(const char *filename, 256 QDict *options, const char *bdref_key, 257 BlockDriverState* parent, 258 const BdrvChildRole *child_role, 259 bool allow_none, Error **errp); 260 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 261 Error **errp); 262 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 263 const char *bdref_key, Error **errp); 264 BlockDriverState *bdrv_open(const char *filename, const char *reference, 265 QDict *options, int flags, Error **errp); 266 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 267 int flags, Error **errp); 268 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 269 BlockDriverState *bs, 270 QDict *options, int flags); 271 int bdrv_reopen_multiple(AioContext *ctx, BlockReopenQueue *bs_queue, Error **errp); 272 int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp); 273 int bdrv_reopen_prepare(BDRVReopenState *reopen_state, 274 BlockReopenQueue *queue, Error **errp); 275 void bdrv_reopen_commit(BDRVReopenState *reopen_state); 276 void bdrv_reopen_abort(BDRVReopenState *reopen_state); 277 int bdrv_read(BdrvChild *child, int64_t sector_num, 278 uint8_t *buf, int nb_sectors); 279 int bdrv_write(BdrvChild *child, int64_t sector_num, 280 const uint8_t *buf, int nb_sectors); 281 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, 282 int bytes, BdrvRequestFlags flags); 283 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); 284 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes); 285 int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 286 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes); 287 int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 288 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, 289 const void *buf, int count); 290 int coroutine_fn bdrv_co_readv(BdrvChild *child, int64_t sector_num, 291 int nb_sectors, QEMUIOVector *qiov); 292 int coroutine_fn bdrv_co_writev(BdrvChild *child, int64_t sector_num, 293 int nb_sectors, QEMUIOVector *qiov); 294 /* 295 * Efficiently zero a region of the disk image. Note that this is a regular 296 * I/O request like read or write and should have a reasonable size. This 297 * function is not suitable for zeroing the entire image in a single request 298 * because it may allocate memory for the entire region. 299 */ 300 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, 301 int bytes, BdrvRequestFlags flags); 302 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 303 const char *backing_file); 304 void bdrv_refresh_filename(BlockDriverState *bs); 305 int bdrv_truncate(BdrvChild *child, int64_t offset, PreallocMode prealloc, 306 Error **errp); 307 int64_t bdrv_nb_sectors(BlockDriverState *bs); 308 int64_t bdrv_getlength(BlockDriverState *bs); 309 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); 310 BlockMeasureInfo *bdrv_measure(BlockDriver *drv, QemuOpts *opts, 311 BlockDriverState *in_bs, Error **errp); 312 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr); 313 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp); 314 int bdrv_commit(BlockDriverState *bs); 315 int bdrv_change_backing_file(BlockDriverState *bs, 316 const char *backing_file, const char *backing_fmt); 317 void bdrv_register(BlockDriver *bdrv); 318 int bdrv_drop_intermediate(BlockDriverState *top, BlockDriverState *base, 319 const char *backing_file_str); 320 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 321 BlockDriverState *bs); 322 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 323 324 325 typedef struct BdrvCheckResult { 326 int corruptions; 327 int leaks; 328 int check_errors; 329 int corruptions_fixed; 330 int leaks_fixed; 331 int64_t image_end_offset; 332 BlockFragInfo bfi; 333 } BdrvCheckResult; 334 335 typedef enum { 336 BDRV_FIX_LEAKS = 1, 337 BDRV_FIX_ERRORS = 2, 338 } BdrvCheckMode; 339 340 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); 341 342 /* The units of offset and total_work_size may be chosen arbitrarily by the 343 * block driver; total_work_size may change during the course of the amendment 344 * operation */ 345 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 346 int64_t total_work_size, void *opaque); 347 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 348 BlockDriverAmendStatusCB *status_cb, void *cb_opaque); 349 350 /* external snapshots */ 351 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs, 352 BlockDriverState *candidate); 353 bool bdrv_is_first_non_filter(BlockDriverState *candidate); 354 355 /* check if a named node can be replaced when doing drive-mirror */ 356 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 357 const char *node_name, Error **errp); 358 359 /* async block I/O */ 360 void bdrv_aio_cancel(BlockAIOCB *acb); 361 void bdrv_aio_cancel_async(BlockAIOCB *acb); 362 363 /* sg packet commands */ 364 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 365 366 /* Invalidate any cached metadata used by image formats */ 367 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp); 368 void bdrv_invalidate_cache_all(Error **errp); 369 int bdrv_inactivate_all(void); 370 371 /* Ensure contents are flushed to disk. */ 372 int bdrv_flush(BlockDriverState *bs); 373 int coroutine_fn bdrv_co_flush(BlockDriverState *bs); 374 int bdrv_flush_all(void); 375 void bdrv_close_all(void); 376 void bdrv_drain(BlockDriverState *bs); 377 void coroutine_fn bdrv_co_drain(BlockDriverState *bs); 378 void bdrv_drain_all_begin(void); 379 void bdrv_drain_all_end(void); 380 void bdrv_drain_all(void); 381 382 #define BDRV_POLL_WHILE(bs, cond) ({ \ 383 bool waited_ = false; \ 384 bool busy_ = true; \ 385 BlockDriverState *bs_ = (bs); \ 386 AioContext *ctx_ = bdrv_get_aio_context(bs_); \ 387 if (aio_context_in_iothread(ctx_)) { \ 388 while ((cond) || busy_) { \ 389 busy_ = aio_poll(ctx_, (cond)); \ 390 waited_ |= !!(cond) | busy_; \ 391 } \ 392 } else { \ 393 assert(qemu_get_current_aio_context() == \ 394 qemu_get_aio_context()); \ 395 /* Ask bdrv_dec_in_flight to wake up the main \ 396 * QEMU AioContext. Extra I/O threads never take \ 397 * other I/O threads' AioContexts (see for example \ 398 * block_job_defer_to_main_loop for how to do it). \ 399 */ \ 400 assert(!bs_->wakeup); \ 401 /* Set bs->wakeup before evaluating cond. */ \ 402 atomic_mb_set(&bs_->wakeup, true); \ 403 while (busy_) { \ 404 if ((cond)) { \ 405 waited_ = busy_ = true; \ 406 aio_context_release(ctx_); \ 407 aio_poll(qemu_get_aio_context(), true); \ 408 aio_context_acquire(ctx_); \ 409 } else { \ 410 busy_ = aio_poll(ctx_, false); \ 411 waited_ |= busy_; \ 412 } \ 413 } \ 414 atomic_set(&bs_->wakeup, false); \ 415 } \ 416 waited_; }) 417 418 int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int bytes); 419 int bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes); 420 int bdrv_has_zero_init_1(BlockDriverState *bs); 421 int bdrv_has_zero_init(BlockDriverState *bs); 422 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs); 423 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs); 424 int bdrv_block_status(BlockDriverState *bs, int64_t offset, 425 int64_t bytes, int64_t *pnum, int64_t *map, 426 BlockDriverState **file); 427 int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base, 428 int64_t offset, int64_t bytes, int64_t *pnum, 429 int64_t *map, BlockDriverState **file); 430 int bdrv_is_allocated(BlockDriverState *bs, int64_t offset, int64_t bytes, 431 int64_t *pnum); 432 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, 433 int64_t offset, int64_t bytes, int64_t *pnum); 434 435 bool bdrv_is_read_only(BlockDriverState *bs); 436 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, 437 bool ignore_allow_rdw, Error **errp); 438 int bdrv_set_read_only(BlockDriverState *bs, bool read_only, Error **errp); 439 bool bdrv_is_sg(BlockDriverState *bs); 440 bool bdrv_is_inserted(BlockDriverState *bs); 441 void bdrv_lock_medium(BlockDriverState *bs, bool locked); 442 void bdrv_eject(BlockDriverState *bs, bool eject_flag); 443 const char *bdrv_get_format_name(BlockDriverState *bs); 444 BlockDriverState *bdrv_find_node(const char *node_name); 445 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp); 446 BlockDriverState *bdrv_lookup_bs(const char *device, 447 const char *node_name, 448 Error **errp); 449 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 450 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 451 452 typedef struct BdrvNextIterator { 453 enum { 454 BDRV_NEXT_BACKEND_ROOTS, 455 BDRV_NEXT_MONITOR_OWNED, 456 } phase; 457 BlockBackend *blk; 458 BlockDriverState *bs; 459 } BdrvNextIterator; 460 461 BlockDriverState *bdrv_first(BdrvNextIterator *it); 462 BlockDriverState *bdrv_next(BdrvNextIterator *it); 463 void bdrv_next_cleanup(BdrvNextIterator *it); 464 465 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 466 bool bdrv_is_encrypted(BlockDriverState *bs); 467 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 468 void *opaque); 469 const char *bdrv_get_node_name(const BlockDriverState *bs); 470 const char *bdrv_get_device_name(const BlockDriverState *bs); 471 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs); 472 int bdrv_get_flags(BlockDriverState *bs); 473 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); 474 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs); 475 void bdrv_round_to_clusters(BlockDriverState *bs, 476 int64_t offset, int64_t bytes, 477 int64_t *cluster_offset, 478 int64_t *cluster_bytes); 479 480 const char *bdrv_get_encrypted_filename(BlockDriverState *bs); 481 void bdrv_get_backing_filename(BlockDriverState *bs, 482 char *filename, int filename_size); 483 void bdrv_get_full_backing_filename(BlockDriverState *bs, 484 char *dest, size_t sz, Error **errp); 485 void bdrv_get_full_backing_filename_from_filename(const char *backed, 486 const char *backing, 487 char *dest, size_t sz, 488 Error **errp); 489 490 int path_has_protocol(const char *path); 491 int path_is_absolute(const char *path); 492 void path_combine(char *dest, int dest_size, 493 const char *base_path, 494 const char *filename); 495 496 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 497 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 498 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 499 int64_t pos, int size); 500 501 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 502 int64_t pos, int size); 503 504 void bdrv_img_create(const char *filename, const char *fmt, 505 const char *base_filename, const char *base_fmt, 506 char *options, uint64_t img_size, int flags, 507 bool quiet, Error **errp); 508 509 /* Returns the alignment in bytes that is required so that no bounce buffer 510 * is required throughout the stack */ 511 size_t bdrv_min_mem_align(BlockDriverState *bs); 512 /* Returns optimal alignment in bytes for bounce buffer */ 513 size_t bdrv_opt_mem_align(BlockDriverState *bs); 514 void *qemu_blockalign(BlockDriverState *bs, size_t size); 515 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 516 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 517 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 518 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 519 520 void bdrv_enable_copy_on_read(BlockDriverState *bs); 521 void bdrv_disable_copy_on_read(BlockDriverState *bs); 522 523 void bdrv_ref(BlockDriverState *bs); 524 void bdrv_unref(BlockDriverState *bs); 525 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 526 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 527 BlockDriverState *child_bs, 528 const char *child_name, 529 const BdrvChildRole *child_role, 530 Error **errp); 531 532 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 533 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 534 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 535 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 536 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 537 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 538 539 #define BLKDBG_EVENT(child, evt) \ 540 do { \ 541 if (child) { \ 542 bdrv_debug_event(child->bs, evt); \ 543 } \ 544 } while (0) 545 546 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 547 548 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 549 const char *tag); 550 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 551 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 552 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 553 554 /** 555 * bdrv_get_aio_context: 556 * 557 * Returns: the currently bound #AioContext 558 */ 559 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 560 561 /** 562 * Transfer control to @co in the aio context of @bs 563 */ 564 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 565 566 /** 567 * bdrv_set_aio_context: 568 * 569 * Changes the #AioContext used for fd handlers, timers, and BHs by this 570 * BlockDriverState and all its children. 571 * 572 * This function must be called with iothread lock held. 573 */ 574 void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context); 575 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 576 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 577 578 void bdrv_io_plug(BlockDriverState *bs); 579 void bdrv_io_unplug(BlockDriverState *bs); 580 581 /** 582 * bdrv_parent_drained_begin: 583 * 584 * Begin a quiesced section of all users of @bs. This is part of 585 * bdrv_drained_begin. 586 */ 587 void bdrv_parent_drained_begin(BlockDriverState *bs, BdrvChild *ignore); 588 589 /** 590 * bdrv_parent_drained_end: 591 * 592 * End a quiesced section of all users of @bs. This is part of 593 * bdrv_drained_end. 594 */ 595 void bdrv_parent_drained_end(BlockDriverState *bs, BdrvChild *ignore); 596 597 /** 598 * bdrv_drained_begin: 599 * 600 * Begin a quiesced section for exclusive access to the BDS, by disabling 601 * external request sources including NBD server and device model. Note that 602 * this doesn't block timers or coroutines from submitting more requests, which 603 * means block_job_pause is still necessary. 604 * 605 * This function can be recursive. 606 */ 607 void bdrv_drained_begin(BlockDriverState *bs); 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 #endif 644