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 "qapi-types.h" 13 #include "qemu/hbitmap.h" 14 15 /* block.c */ 16 typedef struct BlockDriver BlockDriver; 17 typedef struct BdrvChild BdrvChild; 18 typedef struct BdrvChildRole BdrvChildRole; 19 20 typedef struct BlockDriverInfo { 21 /* in bytes, 0 if irrelevant */ 22 int cluster_size; 23 /* offset at which the VM state can be saved (0 if not possible) */ 24 int64_t vm_state_offset; 25 bool is_dirty; 26 /* 27 * True if unallocated blocks read back as zeroes. This is equivalent 28 * to the LBPRZ flag in the SCSI logical block provisioning page. 29 */ 30 bool unallocated_blocks_are_zero; 31 /* 32 * True if the driver can optimize writing zeroes by unmapping 33 * sectors. This is equivalent to the BLKDISCARDZEROES ioctl in Linux 34 * with the difference that in qemu a discard is allowed to silently 35 * fail. Therefore we have to use bdrv_pwrite_zeroes with the 36 * BDRV_REQ_MAY_UNMAP flag for an optimized zero write with unmapping. 37 * After this call the driver has to guarantee that the contents read 38 * back as zero. It is additionally required that the block device is 39 * opened with BDRV_O_UNMAP flag for this to work. 40 */ 41 bool can_write_zeroes_with_unmap; 42 /* 43 * True if this block driver only supports compressed writes 44 */ 45 bool needs_compressed_writes; 46 } BlockDriverInfo; 47 48 typedef struct BlockFragInfo { 49 uint64_t allocated_clusters; 50 uint64_t total_clusters; 51 uint64_t fragmented_clusters; 52 uint64_t compressed_clusters; 53 } BlockFragInfo; 54 55 typedef enum { 56 BDRV_REQ_COPY_ON_READ = 0x1, 57 BDRV_REQ_ZERO_WRITE = 0x2, 58 /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver 59 * is allowed to optimize a write zeroes request by unmapping (discarding) 60 * blocks if it is guaranteed that the result will read back as 61 * zeroes. The flag is only passed to the driver if the block device is 62 * opened with BDRV_O_UNMAP. 63 */ 64 BDRV_REQ_MAY_UNMAP = 0x4, 65 BDRV_REQ_NO_SERIALISING = 0x8, 66 BDRV_REQ_FUA = 0x10, 67 BDRV_REQ_WRITE_COMPRESSED = 0x20, 68 69 /* Mask of valid flags */ 70 BDRV_REQ_MASK = 0x3f, 71 } BdrvRequestFlags; 72 73 typedef struct BlockSizes { 74 uint32_t phys; 75 uint32_t log; 76 } BlockSizes; 77 78 typedef struct HDGeometry { 79 uint32_t heads; 80 uint32_t sectors; 81 uint32_t cylinders; 82 } HDGeometry; 83 84 #define BDRV_O_RDWR 0x0002 85 #define BDRV_O_RESIZE 0x0004 /* request permission for resizing the node */ 86 #define BDRV_O_SNAPSHOT 0x0008 /* open the file read only and save writes in a snapshot */ 87 #define BDRV_O_TEMPORARY 0x0010 /* delete the file after use */ 88 #define BDRV_O_NOCACHE 0x0020 /* do not use the host page cache */ 89 #define BDRV_O_NATIVE_AIO 0x0080 /* use native AIO instead of the thread pool */ 90 #define BDRV_O_NO_BACKING 0x0100 /* don't open the backing file */ 91 #define BDRV_O_NO_FLUSH 0x0200 /* disable flushing on this disk */ 92 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */ 93 #define BDRV_O_INACTIVE 0x0800 /* consistency hint for migration handoff */ 94 #define BDRV_O_CHECK 0x1000 /* open solely for consistency check */ 95 #define BDRV_O_ALLOW_RDWR 0x2000 /* allow reopen to change from r/o to r/w */ 96 #define BDRV_O_UNMAP 0x4000 /* execute guest UNMAP/TRIM operations */ 97 #define BDRV_O_PROTOCOL 0x8000 /* if no block driver is explicitly given: 98 select an appropriate protocol driver, 99 ignoring the format layer */ 100 #define BDRV_O_NO_IO 0x10000 /* don't initialize for I/O */ 101 102 #define BDRV_O_CACHE_MASK (BDRV_O_NOCACHE | BDRV_O_NO_FLUSH) 103 104 105 /* Option names of options parsed by the block layer */ 106 107 #define BDRV_OPT_CACHE_WB "cache.writeback" 108 #define BDRV_OPT_CACHE_DIRECT "cache.direct" 109 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush" 110 #define BDRV_OPT_READ_ONLY "read-only" 111 #define BDRV_OPT_DISCARD "discard" 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 124 * BDRV_BLOCK_DATA: data is read from a file returned by bdrv_get_block_status. 125 * BDRV_BLOCK_ZERO: sectors read as zero 126 * BDRV_BLOCK_OFFSET_VALID: sector stored as raw data in a file returned by 127 * bdrv_get_block_status. 128 * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this 129 * layer (as opposed to the backing file) 130 * BDRV_BLOCK_RAW: used internally to indicate that the request 131 * was answered by the raw driver and that one 132 * should look in bs->file directly. 133 * 134 * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 represent the offset in 135 * bs->file where sector data can be read from as raw data. 136 * 137 * DATA == 0 && ZERO == 0 means that data is read from backing_hd if present. 138 * 139 * DATA ZERO OFFSET_VALID 140 * t t t sectors read as zero, bs->file is zero at offset 141 * t f t sectors read as valid from bs->file at offset 142 * f t t sectors preallocated, read as zero, bs->file not 143 * necessarily zero at offset 144 * f f t sectors preallocated but read from backing_hd, 145 * bs->file contains garbage at offset 146 * t t f sectors preallocated, read as zero, unknown offset 147 * t f f sectors read from unknown file or offset 148 * f t f not allocated or unknown offset, read as zero 149 * f f f not allocated or unknown offset, read from backing_hd 150 */ 151 #define BDRV_BLOCK_DATA 0x01 152 #define BDRV_BLOCK_ZERO 0x02 153 #define BDRV_BLOCK_OFFSET_VALID 0x04 154 #define BDRV_BLOCK_RAW 0x08 155 #define BDRV_BLOCK_ALLOCATED 0x10 156 #define BDRV_BLOCK_OFFSET_MASK BDRV_SECTOR_MASK 157 158 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue; 159 160 typedef struct BDRVReopenState { 161 BlockDriverState *bs; 162 int flags; 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 BLK_PERM_WRITE_UNCHANGED = 0x04, 214 215 /** This permission is required to change the size of a block node. */ 216 BLK_PERM_RESIZE = 0x08, 217 218 /** 219 * This permission is required to change the node that this BdrvChild 220 * points to. 221 */ 222 BLK_PERM_GRAPH_MOD = 0x10, 223 224 BLK_PERM_ALL = 0x1f, 225 }; 226 227 /* disk I/O throttling */ 228 void bdrv_init(void); 229 void bdrv_init_with_whitelist(void); 230 bool bdrv_uses_whitelist(void); 231 BlockDriver *bdrv_find_protocol(const char *filename, 232 bool allow_protocol_prefix, 233 Error **errp); 234 BlockDriver *bdrv_find_format(const char *format_name); 235 int bdrv_create(BlockDriver *drv, const char* filename, 236 QemuOpts *opts, Error **errp); 237 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp); 238 BlockDriverState *bdrv_new(void); 239 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top, 240 Error **errp); 241 void bdrv_replace_node(BlockDriverState *from, BlockDriverState *to, 242 Error **errp); 243 244 int bdrv_parse_cache_mode(const char *mode, int *flags, bool *writethrough); 245 int bdrv_parse_discard_flags(const char *mode, int *flags); 246 BdrvChild *bdrv_open_child(const char *filename, 247 QDict *options, const char *bdref_key, 248 BlockDriverState* parent, 249 const BdrvChildRole *child_role, 250 bool allow_none, Error **errp); 251 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd, 252 Error **errp); 253 int bdrv_open_backing_file(BlockDriverState *bs, QDict *parent_options, 254 const char *bdref_key, Error **errp); 255 BlockDriverState *bdrv_open(const char *filename, const char *reference, 256 QDict *options, int flags, Error **errp); 257 BlockDriverState *bdrv_new_open_driver(BlockDriver *drv, const char *node_name, 258 int flags, Error **errp); 259 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue, 260 BlockDriverState *bs, 261 QDict *options, int flags); 262 int bdrv_reopen_multiple(AioContext *ctx, BlockReopenQueue *bs_queue, Error **errp); 263 int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp); 264 int bdrv_reopen_prepare(BDRVReopenState *reopen_state, 265 BlockReopenQueue *queue, Error **errp); 266 void bdrv_reopen_commit(BDRVReopenState *reopen_state); 267 void bdrv_reopen_abort(BDRVReopenState *reopen_state); 268 int bdrv_read(BdrvChild *child, int64_t sector_num, 269 uint8_t *buf, int nb_sectors); 270 int bdrv_write(BdrvChild *child, int64_t sector_num, 271 const uint8_t *buf, int nb_sectors); 272 int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset, 273 int count, BdrvRequestFlags flags); 274 int bdrv_make_zero(BdrvChild *child, BdrvRequestFlags flags); 275 int bdrv_pread(BdrvChild *child, int64_t offset, void *buf, int bytes); 276 int bdrv_preadv(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 277 int bdrv_pwrite(BdrvChild *child, int64_t offset, const void *buf, int bytes); 278 int bdrv_pwritev(BdrvChild *child, int64_t offset, QEMUIOVector *qiov); 279 int bdrv_pwrite_sync(BdrvChild *child, int64_t offset, 280 const void *buf, int count); 281 int coroutine_fn bdrv_co_readv(BdrvChild *child, int64_t sector_num, 282 int nb_sectors, QEMUIOVector *qiov); 283 int coroutine_fn bdrv_co_writev(BdrvChild *child, int64_t sector_num, 284 int nb_sectors, QEMUIOVector *qiov); 285 /* 286 * Efficiently zero a region of the disk image. Note that this is a regular 287 * I/O request like read or write and should have a reasonable size. This 288 * function is not suitable for zeroing the entire image in a single request 289 * because it may allocate memory for the entire region. 290 */ 291 int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset, 292 int count, BdrvRequestFlags flags); 293 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs, 294 const char *backing_file); 295 int bdrv_get_backing_file_depth(BlockDriverState *bs); 296 void bdrv_refresh_filename(BlockDriverState *bs); 297 int bdrv_truncate(BdrvChild *child, int64_t offset, Error **errp); 298 int64_t bdrv_nb_sectors(BlockDriverState *bs); 299 int64_t bdrv_getlength(BlockDriverState *bs); 300 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs); 301 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr); 302 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp); 303 int bdrv_commit(BlockDriverState *bs); 304 int bdrv_change_backing_file(BlockDriverState *bs, 305 const char *backing_file, const char *backing_fmt); 306 void bdrv_register(BlockDriver *bdrv); 307 int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top, 308 BlockDriverState *base, 309 const char *backing_file_str); 310 BlockDriverState *bdrv_find_overlay(BlockDriverState *active, 311 BlockDriverState *bs); 312 BlockDriverState *bdrv_find_base(BlockDriverState *bs); 313 314 315 typedef struct BdrvCheckResult { 316 int corruptions; 317 int leaks; 318 int check_errors; 319 int corruptions_fixed; 320 int leaks_fixed; 321 int64_t image_end_offset; 322 BlockFragInfo bfi; 323 } BdrvCheckResult; 324 325 typedef enum { 326 BDRV_FIX_LEAKS = 1, 327 BDRV_FIX_ERRORS = 2, 328 } BdrvCheckMode; 329 330 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix); 331 332 /* The units of offset and total_work_size may be chosen arbitrarily by the 333 * block driver; total_work_size may change during the course of the amendment 334 * operation */ 335 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset, 336 int64_t total_work_size, void *opaque); 337 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts, 338 BlockDriverAmendStatusCB *status_cb, void *cb_opaque); 339 340 /* external snapshots */ 341 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs, 342 BlockDriverState *candidate); 343 bool bdrv_is_first_non_filter(BlockDriverState *candidate); 344 345 /* check if a named node can be replaced when doing drive-mirror */ 346 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs, 347 const char *node_name, Error **errp); 348 349 /* async block I/O */ 350 BlockAIOCB *bdrv_aio_readv(BdrvChild *child, int64_t sector_num, 351 QEMUIOVector *iov, int nb_sectors, 352 BlockCompletionFunc *cb, void *opaque); 353 BlockAIOCB *bdrv_aio_writev(BdrvChild *child, int64_t sector_num, 354 QEMUIOVector *iov, int nb_sectors, 355 BlockCompletionFunc *cb, void *opaque); 356 BlockAIOCB *bdrv_aio_flush(BlockDriverState *bs, 357 BlockCompletionFunc *cb, void *opaque); 358 void bdrv_aio_cancel(BlockAIOCB *acb); 359 void bdrv_aio_cancel_async(BlockAIOCB *acb); 360 361 /* sg packet commands */ 362 int bdrv_co_ioctl(BlockDriverState *bs, int req, void *buf); 363 364 /* Invalidate any cached metadata used by image formats */ 365 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp); 366 void bdrv_invalidate_cache_all(Error **errp); 367 int bdrv_inactivate_all(void); 368 369 void blk_resume_after_migration(Error **errp); 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 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 bs_->wakeup = false; \ 414 } \ 415 waited_; }) 416 417 int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int count); 418 int bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, int count); 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 int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num, 424 int nb_sectors, int *pnum, 425 BlockDriverState **file); 426 int64_t bdrv_get_block_status_above(BlockDriverState *bs, 427 BlockDriverState *base, 428 int64_t sector_num, 429 int nb_sectors, int *pnum, 430 BlockDriverState **file); 431 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors, 432 int *pnum); 433 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base, 434 int64_t sector_num, int nb_sectors, int *pnum); 435 436 bool bdrv_is_read_only(BlockDriverState *bs); 437 int bdrv_can_set_read_only(BlockDriverState *bs, bool read_only, 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 int bdrv_media_changed(BlockDriverState *bs); 442 void bdrv_lock_medium(BlockDriverState *bs, bool locked); 443 void bdrv_eject(BlockDriverState *bs, bool eject_flag); 444 const char *bdrv_get_format_name(BlockDriverState *bs); 445 BlockDriverState *bdrv_find_node(const char *node_name); 446 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp); 447 BlockDriverState *bdrv_lookup_bs(const char *device, 448 const char *node_name, 449 Error **errp); 450 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base); 451 BlockDriverState *bdrv_next_node(BlockDriverState *bs); 452 453 typedef struct BdrvNextIterator { 454 enum { 455 BDRV_NEXT_BACKEND_ROOTS, 456 BDRV_NEXT_MONITOR_OWNED, 457 } phase; 458 BlockBackend *blk; 459 BlockDriverState *bs; 460 } BdrvNextIterator; 461 462 BlockDriverState *bdrv_first(BdrvNextIterator *it); 463 BlockDriverState *bdrv_next(BdrvNextIterator *it); 464 465 BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); 466 bool bdrv_is_encrypted(BlockDriverState *bs); 467 bool bdrv_key_required(BlockDriverState *bs); 468 int bdrv_set_key(BlockDriverState *bs, const char *key); 469 void bdrv_add_key(BlockDriverState *bs, const char *key, Error **errp); 470 void bdrv_iterate_format(void (*it)(void *opaque, const char *name), 471 void *opaque); 472 const char *bdrv_get_node_name(const BlockDriverState *bs); 473 const char *bdrv_get_device_name(const BlockDriverState *bs); 474 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs); 475 int bdrv_get_flags(BlockDriverState *bs); 476 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi); 477 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs); 478 void bdrv_round_sectors_to_clusters(BlockDriverState *bs, 479 int64_t sector_num, int nb_sectors, 480 int64_t *cluster_sector_num, 481 int *cluster_nb_sectors); 482 void bdrv_round_to_clusters(BlockDriverState *bs, 483 int64_t offset, unsigned int bytes, 484 int64_t *cluster_offset, 485 unsigned int *cluster_bytes); 486 487 const char *bdrv_get_encrypted_filename(BlockDriverState *bs); 488 void bdrv_get_backing_filename(BlockDriverState *bs, 489 char *filename, int filename_size); 490 void bdrv_get_full_backing_filename(BlockDriverState *bs, 491 char *dest, size_t sz, Error **errp); 492 void bdrv_get_full_backing_filename_from_filename(const char *backed, 493 const char *backing, 494 char *dest, size_t sz, 495 Error **errp); 496 497 int path_has_protocol(const char *path); 498 int path_is_absolute(const char *path); 499 void path_combine(char *dest, int dest_size, 500 const char *base_path, 501 const char *filename); 502 503 int bdrv_readv_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 504 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos); 505 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf, 506 int64_t pos, int size); 507 508 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf, 509 int64_t pos, int size); 510 511 void bdrv_img_create(const char *filename, const char *fmt, 512 const char *base_filename, const char *base_fmt, 513 char *options, uint64_t img_size, int flags, 514 bool quiet, Error **errp); 515 516 /* Returns the alignment in bytes that is required so that no bounce buffer 517 * is required throughout the stack */ 518 size_t bdrv_min_mem_align(BlockDriverState *bs); 519 /* Returns optimal alignment in bytes for bounce buffer */ 520 size_t bdrv_opt_mem_align(BlockDriverState *bs); 521 void *qemu_blockalign(BlockDriverState *bs, size_t size); 522 void *qemu_blockalign0(BlockDriverState *bs, size_t size); 523 void *qemu_try_blockalign(BlockDriverState *bs, size_t size); 524 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size); 525 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); 526 527 void bdrv_enable_copy_on_read(BlockDriverState *bs); 528 void bdrv_disable_copy_on_read(BlockDriverState *bs); 529 530 void bdrv_ref(BlockDriverState *bs); 531 void bdrv_unref(BlockDriverState *bs); 532 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child); 533 BdrvChild *bdrv_attach_child(BlockDriverState *parent_bs, 534 BlockDriverState *child_bs, 535 const char *child_name, 536 const BdrvChildRole *child_role, 537 Error **errp); 538 539 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp); 540 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason); 541 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason); 542 void bdrv_op_block_all(BlockDriverState *bs, Error *reason); 543 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason); 544 bool bdrv_op_blocker_is_empty(BlockDriverState *bs); 545 546 #define BLKDBG_EVENT(child, evt) \ 547 do { \ 548 if (child) { \ 549 bdrv_debug_event(child->bs, evt); \ 550 } \ 551 } while (0) 552 553 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event); 554 555 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event, 556 const char *tag); 557 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag); 558 int bdrv_debug_resume(BlockDriverState *bs, const char *tag); 559 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag); 560 561 /** 562 * bdrv_get_aio_context: 563 * 564 * Returns: the currently bound #AioContext 565 */ 566 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 567 568 /** 569 * Transfer control to @co in the aio context of @bs 570 */ 571 void bdrv_coroutine_enter(BlockDriverState *bs, Coroutine *co); 572 573 /** 574 * bdrv_set_aio_context: 575 * 576 * Changes the #AioContext used for fd handlers, timers, and BHs by this 577 * BlockDriverState and all its children. 578 * 579 * This function must be called with iothread lock held. 580 */ 581 void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context); 582 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz); 583 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo); 584 585 void bdrv_io_plug(BlockDriverState *bs); 586 void bdrv_io_unplug(BlockDriverState *bs); 587 588 /** 589 * bdrv_parent_drained_begin: 590 * 591 * Begin a quiesced section of all users of @bs. This is part of 592 * bdrv_drained_begin. 593 */ 594 void bdrv_parent_drained_begin(BlockDriverState *bs); 595 596 /** 597 * bdrv_parent_drained_end: 598 * 599 * End a quiesced section of all users of @bs. This is part of 600 * bdrv_drained_end. 601 */ 602 void bdrv_parent_drained_end(BlockDriverState *bs); 603 604 /** 605 * bdrv_drained_begin: 606 * 607 * Begin a quiesced section for exclusive access to the BDS, by disabling 608 * external request sources including NBD server and device model. Note that 609 * this doesn't block timers or coroutines from submitting more requests, which 610 * means block_job_pause is still necessary. 611 * 612 * This function can be recursive. 613 */ 614 void bdrv_drained_begin(BlockDriverState *bs); 615 616 /** 617 * bdrv_drained_end: 618 * 619 * End a quiescent section started by bdrv_drained_begin(). 620 */ 621 void bdrv_drained_end(BlockDriverState *bs); 622 623 void bdrv_add_child(BlockDriverState *parent, BlockDriverState *child, 624 Error **errp); 625 void bdrv_del_child(BlockDriverState *parent, BdrvChild *child, Error **errp); 626 627 #endif 628