1 /* 2 * QEMU System Emulator block driver 3 * 4 * Copyright (c) 2003 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 #ifndef BLOCK_INT_H 25 #define BLOCK_INT_H 26 27 #include "block/accounting.h" 28 #include "block/block.h" 29 #include "qemu/option.h" 30 #include "qemu/queue.h" 31 #include "qemu/coroutine.h" 32 #include "qemu/timer.h" 33 #include "qapi-types.h" 34 #include "qemu/hbitmap.h" 35 #include "block/snapshot.h" 36 #include "qemu/main-loop.h" 37 #include "qemu/throttle.h" 38 39 #define BLOCK_FLAG_ENCRYPT 1 40 #define BLOCK_FLAG_LAZY_REFCOUNTS 8 41 42 #define BLOCK_OPT_SIZE "size" 43 #define BLOCK_OPT_ENCRYPT "encryption" 44 #define BLOCK_OPT_COMPAT6 "compat6" 45 #define BLOCK_OPT_HWVERSION "hwversion" 46 #define BLOCK_OPT_BACKING_FILE "backing_file" 47 #define BLOCK_OPT_BACKING_FMT "backing_fmt" 48 #define BLOCK_OPT_CLUSTER_SIZE "cluster_size" 49 #define BLOCK_OPT_TABLE_SIZE "table_size" 50 #define BLOCK_OPT_PREALLOC "preallocation" 51 #define BLOCK_OPT_SUBFMT "subformat" 52 #define BLOCK_OPT_COMPAT_LEVEL "compat" 53 #define BLOCK_OPT_LAZY_REFCOUNTS "lazy_refcounts" 54 #define BLOCK_OPT_ADAPTER_TYPE "adapter_type" 55 #define BLOCK_OPT_REDUNDANCY "redundancy" 56 #define BLOCK_OPT_NOCOW "nocow" 57 #define BLOCK_OPT_OBJECT_SIZE "object_size" 58 #define BLOCK_OPT_REFCOUNT_BITS "refcount_bits" 59 60 #define BLOCK_PROBE_BUF_SIZE 512 61 62 enum BdrvTrackedRequestType { 63 BDRV_TRACKED_READ, 64 BDRV_TRACKED_WRITE, 65 BDRV_TRACKED_FLUSH, 66 BDRV_TRACKED_IOCTL, 67 BDRV_TRACKED_DISCARD, 68 }; 69 70 typedef struct BdrvTrackedRequest { 71 BlockDriverState *bs; 72 int64_t offset; 73 unsigned int bytes; 74 enum BdrvTrackedRequestType type; 75 76 bool serialising; 77 int64_t overlap_offset; 78 unsigned int overlap_bytes; 79 80 QLIST_ENTRY(BdrvTrackedRequest) list; 81 Coroutine *co; /* owner, used for deadlock detection */ 82 CoQueue wait_queue; /* coroutines blocked on this request */ 83 84 struct BdrvTrackedRequest *waiting_for; 85 } BdrvTrackedRequest; 86 87 struct BlockDriver { 88 const char *format_name; 89 int instance_size; 90 91 /* set to true if the BlockDriver is a block filter */ 92 bool is_filter; 93 /* for snapshots block filter like Quorum can implement the 94 * following recursive callback. 95 * It's purpose is to recurse on the filter children while calling 96 * bdrv_recurse_is_first_non_filter on them. 97 * For a sample implementation look in the future Quorum block filter. 98 */ 99 bool (*bdrv_recurse_is_first_non_filter)(BlockDriverState *bs, 100 BlockDriverState *candidate); 101 102 int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename); 103 int (*bdrv_probe_device)(const char *filename); 104 105 /* Any driver implementing this callback is expected to be able to handle 106 * NULL file names in its .bdrv_open() implementation */ 107 void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp); 108 /* Drivers not implementing bdrv_parse_filename nor bdrv_open should have 109 * this field set to true, except ones that are defined only by their 110 * child's bs. 111 * An example of the last type will be the quorum block driver. 112 */ 113 bool bdrv_needs_filename; 114 115 /* Set if a driver can support backing files */ 116 bool supports_backing; 117 118 /* For handling image reopen for split or non-split files */ 119 int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state, 120 BlockReopenQueue *queue, Error **errp); 121 void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state); 122 void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state); 123 void (*bdrv_join_options)(QDict *options, QDict *old_options); 124 125 int (*bdrv_open)(BlockDriverState *bs, QDict *options, int flags, 126 Error **errp); 127 int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags, 128 Error **errp); 129 void (*bdrv_close)(BlockDriverState *bs); 130 int (*bdrv_create)(const char *filename, QemuOpts *opts, Error **errp); 131 int (*bdrv_set_key)(BlockDriverState *bs, const char *key); 132 int (*bdrv_make_empty)(BlockDriverState *bs); 133 134 void (*bdrv_refresh_filename)(BlockDriverState *bs, QDict *options); 135 136 /* aio */ 137 BlockAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs, 138 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 139 BlockCompletionFunc *cb, void *opaque); 140 BlockAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs, 141 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 142 BlockCompletionFunc *cb, void *opaque); 143 BlockAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs, 144 BlockCompletionFunc *cb, void *opaque); 145 BlockAIOCB *(*bdrv_aio_discard)(BlockDriverState *bs, 146 int64_t sector_num, int nb_sectors, 147 BlockCompletionFunc *cb, void *opaque); 148 149 int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs, 150 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); 151 int coroutine_fn (*bdrv_co_preadv)(BlockDriverState *bs, 152 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags); 153 int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs, 154 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); 155 int coroutine_fn (*bdrv_co_writev_flags)(BlockDriverState *bs, 156 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, int flags); 157 int coroutine_fn (*bdrv_co_pwritev)(BlockDriverState *bs, 158 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags); 159 160 /* 161 * Efficiently zero a region of the disk image. Typically an image format 162 * would use a compact metadata representation to implement this. This 163 * function pointer may be NULL or return -ENOSUP and .bdrv_co_writev() 164 * will be called instead. 165 */ 166 int coroutine_fn (*bdrv_co_pwrite_zeroes)(BlockDriverState *bs, 167 int64_t offset, int count, BdrvRequestFlags flags); 168 int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs, 169 int64_t sector_num, int nb_sectors); 170 int64_t coroutine_fn (*bdrv_co_get_block_status)(BlockDriverState *bs, 171 int64_t sector_num, int nb_sectors, int *pnum, 172 BlockDriverState **file); 173 174 /* 175 * Invalidate any cached meta-data. 176 */ 177 void (*bdrv_invalidate_cache)(BlockDriverState *bs, Error **errp); 178 int (*bdrv_inactivate)(BlockDriverState *bs); 179 180 /* 181 * Flushes all data for all layers by calling bdrv_co_flush for underlying 182 * layers, if needed. This function is needed for deterministic 183 * synchronization of the flush finishing callback. 184 */ 185 int coroutine_fn (*bdrv_co_flush)(BlockDriverState *bs); 186 187 /* 188 * Flushes all data that was already written to the OS all the way down to 189 * the disk (for example raw-posix calls fsync()). 190 */ 191 int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs); 192 193 /* 194 * Flushes all internal caches to the OS. The data may still sit in a 195 * writeback cache of the host OS, but it will survive a crash of the qemu 196 * process. 197 */ 198 int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs); 199 200 const char *protocol_name; 201 int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset); 202 203 int64_t (*bdrv_getlength)(BlockDriverState *bs); 204 bool has_variable_length; 205 int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs); 206 207 int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num, 208 const uint8_t *buf, int nb_sectors); 209 210 int (*bdrv_snapshot_create)(BlockDriverState *bs, 211 QEMUSnapshotInfo *sn_info); 212 int (*bdrv_snapshot_goto)(BlockDriverState *bs, 213 const char *snapshot_id); 214 int (*bdrv_snapshot_delete)(BlockDriverState *bs, 215 const char *snapshot_id, 216 const char *name, 217 Error **errp); 218 int (*bdrv_snapshot_list)(BlockDriverState *bs, 219 QEMUSnapshotInfo **psn_info); 220 int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, 221 const char *snapshot_id, 222 const char *name, 223 Error **errp); 224 int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi); 225 ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs); 226 227 int coroutine_fn (*bdrv_save_vmstate)(BlockDriverState *bs, 228 QEMUIOVector *qiov, 229 int64_t pos); 230 int coroutine_fn (*bdrv_load_vmstate)(BlockDriverState *bs, 231 QEMUIOVector *qiov, 232 int64_t pos); 233 234 int (*bdrv_change_backing_file)(BlockDriverState *bs, 235 const char *backing_file, const char *backing_fmt); 236 237 /* removable device specific */ 238 bool (*bdrv_is_inserted)(BlockDriverState *bs); 239 int (*bdrv_media_changed)(BlockDriverState *bs); 240 void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag); 241 void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked); 242 243 /* to control generic scsi devices */ 244 BlockAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs, 245 unsigned long int req, void *buf, 246 BlockCompletionFunc *cb, void *opaque); 247 248 /* List of options for creating images, terminated by name == NULL */ 249 QemuOptsList *create_opts; 250 251 /* 252 * Returns 0 for completed check, -errno for internal errors. 253 * The check results are stored in result. 254 */ 255 int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result, 256 BdrvCheckMode fix); 257 258 int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts, 259 BlockDriverAmendStatusCB *status_cb, 260 void *cb_opaque); 261 262 void (*bdrv_debug_event)(BlockDriverState *bs, BlkdebugEvent event); 263 264 /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */ 265 int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event, 266 const char *tag); 267 int (*bdrv_debug_remove_breakpoint)(BlockDriverState *bs, 268 const char *tag); 269 int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag); 270 bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag); 271 272 void (*bdrv_refresh_limits)(BlockDriverState *bs, Error **errp); 273 274 /* 275 * Returns 1 if newly created images are guaranteed to contain only 276 * zeros, 0 otherwise. 277 */ 278 int (*bdrv_has_zero_init)(BlockDriverState *bs); 279 280 /* Remove fd handlers, timers, and other event loop callbacks so the event 281 * loop is no longer in use. Called with no in-flight requests and in 282 * depth-first traversal order with parents before child nodes. 283 */ 284 void (*bdrv_detach_aio_context)(BlockDriverState *bs); 285 286 /* Add fd handlers, timers, and other event loop callbacks so I/O requests 287 * can be processed again. Called with no in-flight requests and in 288 * depth-first traversal order with child nodes before parent nodes. 289 */ 290 void (*bdrv_attach_aio_context)(BlockDriverState *bs, 291 AioContext *new_context); 292 293 /* io queue for linux-aio */ 294 void (*bdrv_io_plug)(BlockDriverState *bs); 295 void (*bdrv_io_unplug)(BlockDriverState *bs); 296 297 /** 298 * Try to get @bs's logical and physical block size. 299 * On success, store them in @bsz and return zero. 300 * On failure, return negative errno. 301 */ 302 int (*bdrv_probe_blocksizes)(BlockDriverState *bs, BlockSizes *bsz); 303 /** 304 * Try to get @bs's geometry (cyls, heads, sectors) 305 * On success, store them in @geo and return 0. 306 * On failure return -errno. 307 * Only drivers that want to override guest geometry implement this 308 * callback; see hd_geometry_guess(). 309 */ 310 int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo); 311 312 /** 313 * Drain and stop any internal sources of requests in the driver, and 314 * remain so until next I/O callback (e.g. bdrv_co_writev) is called. 315 */ 316 void (*bdrv_drain)(BlockDriverState *bs); 317 318 void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child, 319 Error **errp); 320 void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child, 321 Error **errp); 322 323 QLIST_ENTRY(BlockDriver) list; 324 }; 325 326 typedef struct BlockLimits { 327 /* Alignment requirement, in bytes, for offset/length of I/O 328 * requests. Must be a power of 2 less than INT_MAX; defaults to 329 * 1 for drivers with modern byte interfaces, and to 512 330 * otherwise. */ 331 uint32_t request_alignment; 332 333 /* maximum number of bytes that can be discarded at once (since it 334 * is signed, it must be < 2G, if set), should be multiple of 335 * pdiscard_alignment, but need not be power of 2. May be 0 if no 336 * inherent 32-bit limit */ 337 int32_t max_pdiscard; 338 339 /* optimal alignment for discard requests in bytes, must be power 340 * of 2, less than max_pdiscard if that is set, and multiple of 341 * bl.request_alignment. May be 0 if bl.request_alignment is good 342 * enough */ 343 uint32_t pdiscard_alignment; 344 345 /* maximum number of bytes that can zeroized at once (since it is 346 * signed, it must be < 2G, if set), should be multiple of 347 * pwrite_zeroes_alignment. May be 0 if no inherent 32-bit limit */ 348 int32_t max_pwrite_zeroes; 349 350 /* optimal alignment for write zeroes requests in bytes, must be 351 * power of 2, less than max_pwrite_zeroes if that is set, and 352 * multiple of bl.request_alignment. May be 0 if 353 * bl.request_alignment is good enough */ 354 uint32_t pwrite_zeroes_alignment; 355 356 /* optimal transfer length in bytes (must be power of 2, and 357 * multiple of bl.request_alignment), or 0 if no preferred size */ 358 uint32_t opt_transfer; 359 360 /* maximal transfer length in bytes (need not be power of 2, but 361 * should be multiple of opt_transfer), or 0 for no 32-bit limit. 362 * For now, anything larger than INT_MAX is clamped down. */ 363 uint32_t max_transfer; 364 365 /* memory alignment, in bytes so that no bounce buffer is needed */ 366 size_t min_mem_alignment; 367 368 /* memory alignment, in bytes, for bounce buffer */ 369 size_t opt_mem_alignment; 370 371 /* maximum number of iovec elements */ 372 int max_iov; 373 } BlockLimits; 374 375 typedef struct BdrvOpBlocker BdrvOpBlocker; 376 377 typedef struct BdrvAioNotifier { 378 void (*attached_aio_context)(AioContext *new_context, void *opaque); 379 void (*detach_aio_context)(void *opaque); 380 381 void *opaque; 382 bool deleted; 383 384 QLIST_ENTRY(BdrvAioNotifier) list; 385 } BdrvAioNotifier; 386 387 struct BdrvChildRole { 388 void (*inherit_options)(int *child_flags, QDict *child_options, 389 int parent_flags, QDict *parent_options); 390 391 void (*change_media)(BdrvChild *child, bool load); 392 void (*resize)(BdrvChild *child); 393 394 /* Returns a name that is supposedly more useful for human users than the 395 * node name for identifying the node in question (in particular, a BB 396 * name), or NULL if the parent can't provide a better name. */ 397 const char* (*get_name)(BdrvChild *child); 398 399 /* 400 * If this pair of functions is implemented, the parent doesn't issue new 401 * requests after returning from .drained_begin() until .drained_end() is 402 * called. 403 * 404 * Note that this can be nested. If drained_begin() was called twice, new 405 * I/O is allowed only after drained_end() was called twice, too. 406 */ 407 void (*drained_begin)(BdrvChild *child); 408 void (*drained_end)(BdrvChild *child); 409 }; 410 411 extern const BdrvChildRole child_file; 412 extern const BdrvChildRole child_format; 413 414 struct BdrvChild { 415 BlockDriverState *bs; 416 char *name; 417 const BdrvChildRole *role; 418 void *opaque; 419 QLIST_ENTRY(BdrvChild) next; 420 QLIST_ENTRY(BdrvChild) next_parent; 421 }; 422 423 /* 424 * Note: the function bdrv_append() copies and swaps contents of 425 * BlockDriverStates, so if you add new fields to this struct, please 426 * inspect bdrv_append() to determine if the new fields need to be 427 * copied as well. 428 */ 429 struct BlockDriverState { 430 int64_t total_sectors; /* if we are reading a disk image, give its 431 size in sectors */ 432 int open_flags; /* flags used to open the file, re-used for re-open */ 433 bool read_only; /* if true, the media is read only */ 434 bool encrypted; /* if true, the media is encrypted */ 435 bool valid_key; /* if true, a valid encryption key has been set */ 436 bool sg; /* if true, the device is a /dev/sg* */ 437 bool probed; /* if true, format was probed rather than specified */ 438 439 int copy_on_read; /* if nonzero, copy read backing sectors into image. 440 note this is a reference count */ 441 442 BlockDriver *drv; /* NULL means no media */ 443 void *opaque; 444 445 AioContext *aio_context; /* event loop used for fd handlers, timers, etc */ 446 /* long-running tasks intended to always use the same AioContext as this 447 * BDS may register themselves in this list to be notified of changes 448 * regarding this BDS's context */ 449 QLIST_HEAD(, BdrvAioNotifier) aio_notifiers; 450 bool walking_aio_notifiers; /* to make removal during iteration safe */ 451 452 char filename[PATH_MAX]; 453 char backing_file[PATH_MAX]; /* if non zero, the image is a diff of 454 this file image */ 455 char backing_format[16]; /* if non-zero and backing_file exists */ 456 457 QDict *full_open_options; 458 char exact_filename[PATH_MAX]; 459 460 BdrvChild *backing; 461 BdrvChild *file; 462 463 /* Callback before write request is processed */ 464 NotifierWithReturnList before_write_notifiers; 465 466 /* number of in-flight serialising requests */ 467 unsigned int serialising_in_flight; 468 469 /* Offset after the highest byte written to */ 470 uint64_t wr_highest_offset; 471 472 /* I/O Limits */ 473 BlockLimits bl; 474 475 /* Flags honored during pwrite (so far: BDRV_REQ_FUA) */ 476 unsigned int supported_write_flags; 477 /* Flags honored during pwrite_zeroes (so far: BDRV_REQ_FUA, 478 * BDRV_REQ_MAY_UNMAP) */ 479 unsigned int supported_zero_flags; 480 481 /* the following member gives a name to every node on the bs graph. */ 482 char node_name[32]; 483 /* element of the list of named nodes building the graph */ 484 QTAILQ_ENTRY(BlockDriverState) node_list; 485 /* element of the list of all BlockDriverStates (all_bdrv_states) */ 486 QTAILQ_ENTRY(BlockDriverState) bs_list; 487 /* element of the list of monitor-owned BDS */ 488 QTAILQ_ENTRY(BlockDriverState) monitor_list; 489 QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps; 490 int refcnt; 491 492 QLIST_HEAD(, BdrvTrackedRequest) tracked_requests; 493 494 /* operation blockers */ 495 QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX]; 496 497 /* long-running background operation */ 498 BlockJob *job; 499 500 /* The node that this node inherited default options from (and a reopen on 501 * which can affect this node by changing these defaults). This is always a 502 * parent node of this node. */ 503 BlockDriverState *inherits_from; 504 QLIST_HEAD(, BdrvChild) children; 505 QLIST_HEAD(, BdrvChild) parents; 506 507 QDict *options; 508 QDict *explicit_options; 509 BlockdevDetectZeroesOptions detect_zeroes; 510 511 /* The error object in use for blocking operations on backing_hd */ 512 Error *backing_blocker; 513 514 /* threshold limit for writes, in bytes. "High water mark". */ 515 uint64_t write_threshold_offset; 516 NotifierWithReturn write_threshold_notifier; 517 518 /* counters for nested bdrv_io_plug and bdrv_io_unplugged_begin */ 519 unsigned io_plugged; 520 unsigned io_plug_disabled; 521 522 int quiesce_counter; 523 }; 524 525 struct BlockBackendRootState { 526 int open_flags; 527 bool read_only; 528 BlockdevDetectZeroesOptions detect_zeroes; 529 }; 530 531 typedef enum BlockMirrorBackingMode { 532 /* Reuse the existing backing chain from the source for the target. 533 * - sync=full: Set backing BDS to NULL. 534 * - sync=top: Use source's backing BDS. 535 * - sync=none: Use source as the backing BDS. */ 536 MIRROR_SOURCE_BACKING_CHAIN, 537 538 /* Open the target's backing chain completely anew */ 539 MIRROR_OPEN_BACKING_CHAIN, 540 541 /* Do not change the target's backing BDS after job completion */ 542 MIRROR_LEAVE_BACKING_CHAIN, 543 } BlockMirrorBackingMode; 544 545 static inline BlockDriverState *backing_bs(BlockDriverState *bs) 546 { 547 return bs->backing ? bs->backing->bs : NULL; 548 } 549 550 551 /* Essential block drivers which must always be statically linked into qemu, and 552 * which therefore can be accessed without using bdrv_find_format() */ 553 extern BlockDriver bdrv_file; 554 extern BlockDriver bdrv_raw; 555 extern BlockDriver bdrv_qcow2; 556 557 /** 558 * bdrv_setup_io_funcs: 559 * 560 * Prepare a #BlockDriver for I/O request processing by populating 561 * unimplemented coroutine and AIO interfaces with generic wrapper functions 562 * that fall back to implemented interfaces. 563 */ 564 void bdrv_setup_io_funcs(BlockDriver *bdrv); 565 566 int coroutine_fn bdrv_co_preadv(BdrvChild *child, 567 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 568 BdrvRequestFlags flags); 569 int coroutine_fn bdrv_co_pwritev(BdrvChild *child, 570 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 571 BdrvRequestFlags flags); 572 573 int get_tmp_filename(char *filename, int size); 574 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, 575 const char *filename); 576 577 578 /** 579 * bdrv_add_before_write_notifier: 580 * 581 * Register a callback that is invoked before write requests are processed but 582 * after any throttling or waiting for overlapping requests. 583 */ 584 void bdrv_add_before_write_notifier(BlockDriverState *bs, 585 NotifierWithReturn *notifier); 586 587 /** 588 * bdrv_detach_aio_context: 589 * 590 * May be called from .bdrv_detach_aio_context() to detach children from the 591 * current #AioContext. This is only needed by block drivers that manage their 592 * own children. Both ->file and ->backing are automatically handled and 593 * block drivers should not call this function on them explicitly. 594 */ 595 void bdrv_detach_aio_context(BlockDriverState *bs); 596 597 /** 598 * bdrv_attach_aio_context: 599 * 600 * May be called from .bdrv_attach_aio_context() to attach children to the new 601 * #AioContext. This is only needed by block drivers that manage their own 602 * children. Both ->file and ->backing are automatically handled and block 603 * drivers should not call this function on them explicitly. 604 */ 605 void bdrv_attach_aio_context(BlockDriverState *bs, 606 AioContext *new_context); 607 608 /** 609 * bdrv_add_aio_context_notifier: 610 * 611 * If a long-running job intends to be always run in the same AioContext as a 612 * certain BDS, it may use this function to be notified of changes regarding the 613 * association of the BDS to an AioContext. 614 * 615 * attached_aio_context() is called after the target BDS has been attached to a 616 * new AioContext; detach_aio_context() is called before the target BDS is being 617 * detached from its old AioContext. 618 */ 619 void bdrv_add_aio_context_notifier(BlockDriverState *bs, 620 void (*attached_aio_context)(AioContext *new_context, void *opaque), 621 void (*detach_aio_context)(void *opaque), void *opaque); 622 623 /** 624 * bdrv_remove_aio_context_notifier: 625 * 626 * Unsubscribe of change notifications regarding the BDS's AioContext. The 627 * parameters given here have to be the same as those given to 628 * bdrv_add_aio_context_notifier(). 629 */ 630 void bdrv_remove_aio_context_notifier(BlockDriverState *bs, 631 void (*aio_context_attached)(AioContext *, 632 void *), 633 void (*aio_context_detached)(void *), 634 void *opaque); 635 636 #ifdef _WIN32 637 int is_windows_drive(const char *filename); 638 #endif 639 640 /** 641 * stream_start: 642 * @bs: Block device to operate on. 643 * @base: Block device that will become the new base, or %NULL to 644 * flatten the whole backing file chain onto @bs. 645 * @base_id: The file name that will be written to @bs as the new 646 * backing file if the job completes. Ignored if @base is %NULL. 647 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 648 * @on_error: The action to take upon error. 649 * @cb: Completion function for the job. 650 * @opaque: Opaque pointer value passed to @cb. 651 * @errp: Error object. 652 * 653 * Start a streaming operation on @bs. Clusters that are unallocated 654 * in @bs, but allocated in any image between @base and @bs (both 655 * exclusive) will be written to @bs. At the end of a successful 656 * streaming job, the backing file of @bs will be changed to 657 * @base_id in the written image and to @base in the live BlockDriverState. 658 */ 659 void stream_start(BlockDriverState *bs, BlockDriverState *base, 660 const char *base_id, int64_t speed, BlockdevOnError on_error, 661 BlockCompletionFunc *cb, 662 void *opaque, Error **errp); 663 664 /** 665 * commit_start: 666 * @bs: Active block device. 667 * @top: Top block device to be committed. 668 * @base: Block device that will be written into, and become the new top. 669 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 670 * @on_error: The action to take upon error. 671 * @cb: Completion function for the job. 672 * @opaque: Opaque pointer value passed to @cb. 673 * @backing_file_str: String to use as the backing file in @top's overlay 674 * @errp: Error object. 675 * 676 */ 677 void commit_start(BlockDriverState *bs, BlockDriverState *base, 678 BlockDriverState *top, int64_t speed, 679 BlockdevOnError on_error, BlockCompletionFunc *cb, 680 void *opaque, const char *backing_file_str, Error **errp); 681 /** 682 * commit_active_start: 683 * @bs: Active block device to be committed. 684 * @base: Block device that will be written into, and become the new top. 685 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 686 * @on_error: The action to take upon error. 687 * @cb: Completion function for the job. 688 * @opaque: Opaque pointer value passed to @cb. 689 * @errp: Error object. 690 * 691 */ 692 void commit_active_start(BlockDriverState *bs, BlockDriverState *base, 693 int64_t speed, 694 BlockdevOnError on_error, 695 BlockCompletionFunc *cb, 696 void *opaque, Error **errp); 697 /* 698 * mirror_start: 699 * @bs: Block device to operate on. 700 * @target: Block device to write to. 701 * @replaces: Block graph node name to replace once the mirror is done. Can 702 * only be used when full mirroring is selected. 703 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 704 * @granularity: The chosen granularity for the dirty bitmap. 705 * @buf_size: The amount of data that can be in flight at one time. 706 * @mode: Whether to collapse all images in the chain to the target. 707 * @backing_mode: How to establish the target's backing chain after completion. 708 * @on_source_error: The action to take upon error reading from the source. 709 * @on_target_error: The action to take upon error writing to the target. 710 * @unmap: Whether to unmap target where source sectors only contain zeroes. 711 * @cb: Completion function for the job. 712 * @opaque: Opaque pointer value passed to @cb. 713 * @errp: Error object. 714 * 715 * Start a mirroring operation on @bs. Clusters that are allocated 716 * in @bs will be written to @bs until the job is cancelled or 717 * manually completed. At the end of a successful mirroring job, 718 * @bs will be switched to read from @target. 719 */ 720 void mirror_start(BlockDriverState *bs, BlockDriverState *target, 721 const char *replaces, 722 int64_t speed, uint32_t granularity, int64_t buf_size, 723 MirrorSyncMode mode, BlockMirrorBackingMode backing_mode, 724 BlockdevOnError on_source_error, 725 BlockdevOnError on_target_error, 726 bool unmap, 727 BlockCompletionFunc *cb, 728 void *opaque, Error **errp); 729 730 /* 731 * backup_start: 732 * @bs: Block device to operate on. 733 * @target: Block device to write to. 734 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 735 * @sync_mode: What parts of the disk image should be copied to the destination. 736 * @sync_bitmap: The dirty bitmap if sync_mode is MIRROR_SYNC_MODE_INCREMENTAL. 737 * @on_source_error: The action to take upon error reading from the source. 738 * @on_target_error: The action to take upon error writing to the target. 739 * @cb: Completion function for the job. 740 * @opaque: Opaque pointer value passed to @cb. 741 * @txn: Transaction that this job is part of (may be NULL). 742 * 743 * Start a backup operation on @bs. Clusters in @bs are written to @target 744 * until the job is cancelled or manually completed. 745 */ 746 void backup_start(BlockDriverState *bs, BlockDriverState *target, 747 int64_t speed, MirrorSyncMode sync_mode, 748 BdrvDirtyBitmap *sync_bitmap, 749 BlockdevOnError on_source_error, 750 BlockdevOnError on_target_error, 751 BlockCompletionFunc *cb, void *opaque, 752 BlockJobTxn *txn, Error **errp); 753 754 void hmp_drive_add_node(Monitor *mon, const char *optstr); 755 756 BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, 757 const char *child_name, 758 const BdrvChildRole *child_role, 759 void *opaque); 760 void bdrv_root_unref_child(BdrvChild *child); 761 762 const char *bdrv_get_parent_name(const BlockDriverState *bs); 763 void blk_dev_change_media_cb(BlockBackend *blk, bool load); 764 bool blk_dev_has_removable_media(BlockBackend *blk); 765 bool blk_dev_has_tray(BlockBackend *blk); 766 void blk_dev_eject_request(BlockBackend *blk, bool force); 767 bool blk_dev_is_tray_open(BlockBackend *blk); 768 bool blk_dev_is_medium_locked(BlockBackend *blk); 769 770 void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors); 771 bool bdrv_requests_pending(BlockDriverState *bs); 772 773 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out); 774 void bdrv_undo_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *in); 775 776 void blockdev_close_all_bdrv_states(void); 777 778 #endif /* BLOCK_INT_H */ 779