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 /* maximum number of sectors that can be discarded at once */ 328 int max_discard; 329 330 /* optimal alignment for discard requests in sectors */ 331 int64_t discard_alignment; 332 333 /* maximum number of bytes that can zeroized at once (since it is 334 * signed, it must be < 2G, if set) */ 335 int32_t max_pwrite_zeroes; 336 337 /* optimal alignment for write zeroes requests in bytes, must be 338 * power of 2, and less than max_pwrite_zeroes if that is set */ 339 uint32_t pwrite_zeroes_alignment; 340 341 /* optimal transfer length in sectors */ 342 int opt_transfer_length; 343 344 /* maximal transfer length in sectors */ 345 int max_transfer_length; 346 347 /* memory alignment so that no bounce buffer is needed */ 348 size_t min_mem_alignment; 349 350 /* memory alignment for bounce buffer */ 351 size_t opt_mem_alignment; 352 353 /* maximum number of iovec elements */ 354 int max_iov; 355 } BlockLimits; 356 357 typedef struct BdrvOpBlocker BdrvOpBlocker; 358 359 typedef struct BdrvAioNotifier { 360 void (*attached_aio_context)(AioContext *new_context, void *opaque); 361 void (*detach_aio_context)(void *opaque); 362 363 void *opaque; 364 bool deleted; 365 366 QLIST_ENTRY(BdrvAioNotifier) list; 367 } BdrvAioNotifier; 368 369 struct BdrvChildRole { 370 void (*inherit_options)(int *child_flags, QDict *child_options, 371 int parent_flags, QDict *parent_options); 372 373 void (*change_media)(BdrvChild *child, bool load); 374 void (*resize)(BdrvChild *child); 375 376 /* Returns a name that is supposedly more useful for human users than the 377 * node name for identifying the node in question (in particular, a BB 378 * name), or NULL if the parent can't provide a better name. */ 379 const char* (*get_name)(BdrvChild *child); 380 381 /* 382 * If this pair of functions is implemented, the parent doesn't issue new 383 * requests after returning from .drained_begin() until .drained_end() is 384 * called. 385 * 386 * Note that this can be nested. If drained_begin() was called twice, new 387 * I/O is allowed only after drained_end() was called twice, too. 388 */ 389 void (*drained_begin)(BdrvChild *child); 390 void (*drained_end)(BdrvChild *child); 391 }; 392 393 extern const BdrvChildRole child_file; 394 extern const BdrvChildRole child_format; 395 396 struct BdrvChild { 397 BlockDriverState *bs; 398 char *name; 399 const BdrvChildRole *role; 400 void *opaque; 401 QLIST_ENTRY(BdrvChild) next; 402 QLIST_ENTRY(BdrvChild) next_parent; 403 }; 404 405 /* 406 * Note: the function bdrv_append() copies and swaps contents of 407 * BlockDriverStates, so if you add new fields to this struct, please 408 * inspect bdrv_append() to determine if the new fields need to be 409 * copied as well. 410 */ 411 struct BlockDriverState { 412 int64_t total_sectors; /* if we are reading a disk image, give its 413 size in sectors */ 414 int read_only; /* if true, the media is read only */ 415 int open_flags; /* flags used to open the file, re-used for re-open */ 416 int encrypted; /* if true, the media is encrypted */ 417 int valid_key; /* if true, a valid encryption key has been set */ 418 int sg; /* if true, the device is a /dev/sg* */ 419 int copy_on_read; /* if true, copy read backing sectors into image 420 note this is a reference count */ 421 bool probed; 422 423 BlockDriver *drv; /* NULL means no media */ 424 void *opaque; 425 426 AioContext *aio_context; /* event loop used for fd handlers, timers, etc */ 427 /* long-running tasks intended to always use the same AioContext as this 428 * BDS may register themselves in this list to be notified of changes 429 * regarding this BDS's context */ 430 QLIST_HEAD(, BdrvAioNotifier) aio_notifiers; 431 bool walking_aio_notifiers; /* to make removal during iteration safe */ 432 433 char filename[PATH_MAX]; 434 char backing_file[PATH_MAX]; /* if non zero, the image is a diff of 435 this file image */ 436 char backing_format[16]; /* if non-zero and backing_file exists */ 437 438 QDict *full_open_options; 439 char exact_filename[PATH_MAX]; 440 441 BdrvChild *backing; 442 BdrvChild *file; 443 444 /* Callback before write request is processed */ 445 NotifierWithReturnList before_write_notifiers; 446 447 /* number of in-flight serialising requests */ 448 unsigned int serialising_in_flight; 449 450 /* Offset after the highest byte written to */ 451 uint64_t wr_highest_offset; 452 453 /* I/O Limits */ 454 BlockLimits bl; 455 456 /* Alignment requirement for offset/length of I/O requests */ 457 unsigned int request_alignment; 458 /* Flags honored during pwrite (so far: BDRV_REQ_FUA) */ 459 unsigned int supported_write_flags; 460 /* Flags honored during pwrite_zeroes (so far: BDRV_REQ_FUA, 461 * BDRV_REQ_MAY_UNMAP) */ 462 unsigned int supported_zero_flags; 463 464 /* the following member gives a name to every node on the bs graph. */ 465 char node_name[32]; 466 /* element of the list of named nodes building the graph */ 467 QTAILQ_ENTRY(BlockDriverState) node_list; 468 /* element of the list of all BlockDriverStates (all_bdrv_states) */ 469 QTAILQ_ENTRY(BlockDriverState) bs_list; 470 /* element of the list of monitor-owned BDS */ 471 QTAILQ_ENTRY(BlockDriverState) monitor_list; 472 QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps; 473 int refcnt; 474 475 QLIST_HEAD(, BdrvTrackedRequest) tracked_requests; 476 477 /* operation blockers */ 478 QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX]; 479 480 /* long-running background operation */ 481 BlockJob *job; 482 483 /* The node that this node inherited default options from (and a reopen on 484 * which can affect this node by changing these defaults). This is always a 485 * parent node of this node. */ 486 BlockDriverState *inherits_from; 487 QLIST_HEAD(, BdrvChild) children; 488 QLIST_HEAD(, BdrvChild) parents; 489 490 QDict *options; 491 QDict *explicit_options; 492 BlockdevDetectZeroesOptions detect_zeroes; 493 494 /* The error object in use for blocking operations on backing_hd */ 495 Error *backing_blocker; 496 497 /* threshold limit for writes, in bytes. "High water mark". */ 498 uint64_t write_threshold_offset; 499 NotifierWithReturn write_threshold_notifier; 500 501 /* counters for nested bdrv_io_plug and bdrv_io_unplugged_begin */ 502 unsigned io_plugged; 503 unsigned io_plug_disabled; 504 505 int quiesce_counter; 506 }; 507 508 struct BlockBackendRootState { 509 int open_flags; 510 bool read_only; 511 BlockdevDetectZeroesOptions detect_zeroes; 512 }; 513 514 typedef enum BlockMirrorBackingMode { 515 /* Reuse the existing backing chain from the source for the target. 516 * - sync=full: Set backing BDS to NULL. 517 * - sync=top: Use source's backing BDS. 518 * - sync=none: Use source as the backing BDS. */ 519 MIRROR_SOURCE_BACKING_CHAIN, 520 521 /* Open the target's backing chain completely anew */ 522 MIRROR_OPEN_BACKING_CHAIN, 523 524 /* Do not change the target's backing BDS after job completion */ 525 MIRROR_LEAVE_BACKING_CHAIN, 526 } BlockMirrorBackingMode; 527 528 static inline BlockDriverState *backing_bs(BlockDriverState *bs) 529 { 530 return bs->backing ? bs->backing->bs : NULL; 531 } 532 533 534 /* Essential block drivers which must always be statically linked into qemu, and 535 * which therefore can be accessed without using bdrv_find_format() */ 536 extern BlockDriver bdrv_file; 537 extern BlockDriver bdrv_raw; 538 extern BlockDriver bdrv_qcow2; 539 540 /** 541 * bdrv_setup_io_funcs: 542 * 543 * Prepare a #BlockDriver for I/O request processing by populating 544 * unimplemented coroutine and AIO interfaces with generic wrapper functions 545 * that fall back to implemented interfaces. 546 */ 547 void bdrv_setup_io_funcs(BlockDriver *bdrv); 548 549 int coroutine_fn bdrv_co_preadv(BlockDriverState *bs, 550 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 551 BdrvRequestFlags flags); 552 int coroutine_fn bdrv_co_pwritev(BlockDriverState *bs, 553 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 554 BdrvRequestFlags flags); 555 556 int get_tmp_filename(char *filename, int size); 557 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, 558 const char *filename); 559 560 561 /** 562 * bdrv_add_before_write_notifier: 563 * 564 * Register a callback that is invoked before write requests are processed but 565 * after any throttling or waiting for overlapping requests. 566 */ 567 void bdrv_add_before_write_notifier(BlockDriverState *bs, 568 NotifierWithReturn *notifier); 569 570 /** 571 * bdrv_detach_aio_context: 572 * 573 * May be called from .bdrv_detach_aio_context() to detach children from the 574 * current #AioContext. This is only needed by block drivers that manage their 575 * own children. Both ->file and ->backing are automatically handled and 576 * block drivers should not call this function on them explicitly. 577 */ 578 void bdrv_detach_aio_context(BlockDriverState *bs); 579 580 /** 581 * bdrv_attach_aio_context: 582 * 583 * May be called from .bdrv_attach_aio_context() to attach children to the new 584 * #AioContext. This is only needed by block drivers that manage their own 585 * children. Both ->file and ->backing are automatically handled and block 586 * drivers should not call this function on them explicitly. 587 */ 588 void bdrv_attach_aio_context(BlockDriverState *bs, 589 AioContext *new_context); 590 591 /** 592 * bdrv_add_aio_context_notifier: 593 * 594 * If a long-running job intends to be always run in the same AioContext as a 595 * certain BDS, it may use this function to be notified of changes regarding the 596 * association of the BDS to an AioContext. 597 * 598 * attached_aio_context() is called after the target BDS has been attached to a 599 * new AioContext; detach_aio_context() is called before the target BDS is being 600 * detached from its old AioContext. 601 */ 602 void bdrv_add_aio_context_notifier(BlockDriverState *bs, 603 void (*attached_aio_context)(AioContext *new_context, void *opaque), 604 void (*detach_aio_context)(void *opaque), void *opaque); 605 606 /** 607 * bdrv_remove_aio_context_notifier: 608 * 609 * Unsubscribe of change notifications regarding the BDS's AioContext. The 610 * parameters given here have to be the same as those given to 611 * bdrv_add_aio_context_notifier(). 612 */ 613 void bdrv_remove_aio_context_notifier(BlockDriverState *bs, 614 void (*aio_context_attached)(AioContext *, 615 void *), 616 void (*aio_context_detached)(void *), 617 void *opaque); 618 619 #ifdef _WIN32 620 int is_windows_drive(const char *filename); 621 #endif 622 623 /** 624 * stream_start: 625 * @bs: Block device to operate on. 626 * @base: Block device that will become the new base, or %NULL to 627 * flatten the whole backing file chain onto @bs. 628 * @base_id: The file name that will be written to @bs as the new 629 * backing file if the job completes. Ignored if @base is %NULL. 630 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 631 * @on_error: The action to take upon error. 632 * @cb: Completion function for the job. 633 * @opaque: Opaque pointer value passed to @cb. 634 * @errp: Error object. 635 * 636 * Start a streaming operation on @bs. Clusters that are unallocated 637 * in @bs, but allocated in any image between @base and @bs (both 638 * exclusive) will be written to @bs. At the end of a successful 639 * streaming job, the backing file of @bs will be changed to 640 * @base_id in the written image and to @base in the live BlockDriverState. 641 */ 642 void stream_start(BlockDriverState *bs, BlockDriverState *base, 643 const char *base_id, int64_t speed, BlockdevOnError on_error, 644 BlockCompletionFunc *cb, 645 void *opaque, Error **errp); 646 647 /** 648 * commit_start: 649 * @bs: Active block device. 650 * @top: Top block device to be committed. 651 * @base: Block device that will be written into, and become the new top. 652 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 653 * @on_error: The action to take upon error. 654 * @cb: Completion function for the job. 655 * @opaque: Opaque pointer value passed to @cb. 656 * @backing_file_str: String to use as the backing file in @top's overlay 657 * @errp: Error object. 658 * 659 */ 660 void commit_start(BlockDriverState *bs, BlockDriverState *base, 661 BlockDriverState *top, int64_t speed, 662 BlockdevOnError on_error, BlockCompletionFunc *cb, 663 void *opaque, const char *backing_file_str, Error **errp); 664 /** 665 * commit_active_start: 666 * @bs: Active block device to be committed. 667 * @base: Block device that will be written into, and become the new top. 668 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 669 * @on_error: The action to take upon error. 670 * @cb: Completion function for the job. 671 * @opaque: Opaque pointer value passed to @cb. 672 * @errp: Error object. 673 * 674 */ 675 void commit_active_start(BlockDriverState *bs, BlockDriverState *base, 676 int64_t speed, 677 BlockdevOnError on_error, 678 BlockCompletionFunc *cb, 679 void *opaque, Error **errp); 680 /* 681 * mirror_start: 682 * @bs: Block device to operate on. 683 * @target: Block device to write to. 684 * @replaces: Block graph node name to replace once the mirror is done. Can 685 * only be used when full mirroring is selected. 686 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 687 * @granularity: The chosen granularity for the dirty bitmap. 688 * @buf_size: The amount of data that can be in flight at one time. 689 * @mode: Whether to collapse all images in the chain to the target. 690 * @backing_mode: How to establish the target's backing chain after completion. 691 * @on_source_error: The action to take upon error reading from the source. 692 * @on_target_error: The action to take upon error writing to the target. 693 * @unmap: Whether to unmap target where source sectors only contain zeroes. 694 * @cb: Completion function for the job. 695 * @opaque: Opaque pointer value passed to @cb. 696 * @errp: Error object. 697 * 698 * Start a mirroring operation on @bs. Clusters that are allocated 699 * in @bs will be written to @bs until the job is cancelled or 700 * manually completed. At the end of a successful mirroring job, 701 * @bs will be switched to read from @target. 702 */ 703 void mirror_start(BlockDriverState *bs, BlockDriverState *target, 704 const char *replaces, 705 int64_t speed, uint32_t granularity, int64_t buf_size, 706 MirrorSyncMode mode, BlockMirrorBackingMode backing_mode, 707 BlockdevOnError on_source_error, 708 BlockdevOnError on_target_error, 709 bool unmap, 710 BlockCompletionFunc *cb, 711 void *opaque, Error **errp); 712 713 /* 714 * backup_start: 715 * @bs: Block device to operate on. 716 * @target: Block device to write to. 717 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 718 * @sync_mode: What parts of the disk image should be copied to the destination. 719 * @sync_bitmap: The dirty bitmap if sync_mode is MIRROR_SYNC_MODE_INCREMENTAL. 720 * @on_source_error: The action to take upon error reading from the source. 721 * @on_target_error: The action to take upon error writing to the target. 722 * @cb: Completion function for the job. 723 * @opaque: Opaque pointer value passed to @cb. 724 * @txn: Transaction that this job is part of (may be NULL). 725 * 726 * Start a backup operation on @bs. Clusters in @bs are written to @target 727 * until the job is cancelled or manually completed. 728 */ 729 void backup_start(BlockDriverState *bs, BlockDriverState *target, 730 int64_t speed, MirrorSyncMode sync_mode, 731 BdrvDirtyBitmap *sync_bitmap, 732 BlockdevOnError on_source_error, 733 BlockdevOnError on_target_error, 734 BlockCompletionFunc *cb, void *opaque, 735 BlockJobTxn *txn, Error **errp); 736 737 void hmp_drive_add_node(Monitor *mon, const char *optstr); 738 739 BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, 740 const char *child_name, 741 const BdrvChildRole *child_role, 742 void *opaque); 743 void bdrv_root_unref_child(BdrvChild *child); 744 745 const char *bdrv_get_parent_name(const BlockDriverState *bs); 746 void blk_dev_change_media_cb(BlockBackend *blk, bool load); 747 bool blk_dev_has_removable_media(BlockBackend *blk); 748 bool blk_dev_has_tray(BlockBackend *blk); 749 void blk_dev_eject_request(BlockBackend *blk, bool force); 750 bool blk_dev_is_tray_open(BlockBackend *blk); 751 bool blk_dev_is_medium_locked(BlockBackend *blk); 752 753 void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors); 754 bool bdrv_requests_pending(BlockDriverState *bs); 755 756 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out); 757 void bdrv_undo_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *in); 758 759 void blockdev_close_all_bdrv_states(void); 760 761 #endif /* BLOCK_INT_H */ 762