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 "block/aio-wait.h" 30 #include "qemu/queue.h" 31 #include "qemu/coroutine.h" 32 #include "qemu/stats64.h" 33 #include "qemu/timer.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_LAZY_REFCOUNTS 8 40 41 #define BLOCK_OPT_SIZE "size" 42 #define BLOCK_OPT_ENCRYPT "encryption" 43 #define BLOCK_OPT_ENCRYPT_FORMAT "encrypt.format" 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 #define BLOCK_OPT_DATA_FILE "data_file" 60 #define BLOCK_OPT_DATA_FILE_RAW "data_file_raw" 61 62 #define BLOCK_PROBE_BUF_SIZE 512 63 64 enum BdrvTrackedRequestType { 65 BDRV_TRACKED_READ, 66 BDRV_TRACKED_WRITE, 67 BDRV_TRACKED_DISCARD, 68 BDRV_TRACKED_TRUNCATE, 69 }; 70 71 typedef struct BdrvTrackedRequest { 72 BlockDriverState *bs; 73 int64_t offset; 74 uint64_t bytes; 75 enum BdrvTrackedRequestType type; 76 77 bool serialising; 78 int64_t overlap_offset; 79 uint64_t overlap_bytes; 80 81 QLIST_ENTRY(BdrvTrackedRequest) list; 82 Coroutine *co; /* owner, used for deadlock detection */ 83 CoQueue wait_queue; /* coroutines blocked on this request */ 84 85 struct BdrvTrackedRequest *waiting_for; 86 } BdrvTrackedRequest; 87 88 struct BlockDriver { 89 const char *format_name; 90 int instance_size; 91 92 /* set to true if the BlockDriver is a block filter. Block filters pass 93 * certain callbacks that refer to data (see block.c) to their bs->file if 94 * the driver doesn't implement them. Drivers that do not wish to forward 95 * must implement them and return -ENOTSUP. 96 */ 97 bool is_filter; 98 /* for snapshots block filter like Quorum can implement the 99 * following recursive callback. 100 * It's purpose is to recurse on the filter children while calling 101 * bdrv_recurse_is_first_non_filter on them. 102 * For a sample implementation look in the future Quorum block filter. 103 */ 104 bool (*bdrv_recurse_is_first_non_filter)(BlockDriverState *bs, 105 BlockDriverState *candidate); 106 107 int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename); 108 int (*bdrv_probe_device)(const char *filename); 109 110 /* Any driver implementing this callback is expected to be able to handle 111 * NULL file names in its .bdrv_open() implementation */ 112 void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp); 113 /* Drivers not implementing bdrv_parse_filename nor bdrv_open should have 114 * this field set to true, except ones that are defined only by their 115 * child's bs. 116 * An example of the last type will be the quorum block driver. 117 */ 118 bool bdrv_needs_filename; 119 120 /* Set if a driver can support backing files */ 121 bool supports_backing; 122 123 /* For handling image reopen for split or non-split files */ 124 int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state, 125 BlockReopenQueue *queue, Error **errp); 126 void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state); 127 void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state); 128 void (*bdrv_join_options)(QDict *options, QDict *old_options); 129 130 int (*bdrv_open)(BlockDriverState *bs, QDict *options, int flags, 131 Error **errp); 132 133 /* Protocol drivers should implement this instead of bdrv_open */ 134 int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags, 135 Error **errp); 136 void (*bdrv_close)(BlockDriverState *bs); 137 int coroutine_fn (*bdrv_co_create)(BlockdevCreateOptions *opts, 138 Error **errp); 139 int coroutine_fn (*bdrv_co_create_opts)(const char *filename, 140 QemuOpts *opts, 141 Error **errp); 142 int (*bdrv_make_empty)(BlockDriverState *bs); 143 144 /* 145 * Refreshes the bs->exact_filename field. If that is impossible, 146 * bs->exact_filename has to be left empty. 147 */ 148 void (*bdrv_refresh_filename)(BlockDriverState *bs); 149 150 /* 151 * Gathers the open options for all children into @target. 152 * A simple format driver (without backing file support) might 153 * implement this function like this: 154 * 155 * QINCREF(bs->file->bs->full_open_options); 156 * qdict_put(target, "file", bs->file->bs->full_open_options); 157 * 158 * If not specified, the generic implementation will simply put 159 * all children's options under their respective name. 160 * 161 * @backing_overridden is true when bs->backing seems not to be 162 * the child that would result from opening bs->backing_file. 163 * Therefore, if it is true, the backing child's options should be 164 * gathered; otherwise, there is no need since the backing child 165 * is the one implied by the image header. 166 * 167 * Note that ideally this function would not be needed. Every 168 * block driver which implements it is probably doing something 169 * shady regarding its runtime option structure. 170 */ 171 void (*bdrv_gather_child_options)(BlockDriverState *bs, QDict *target, 172 bool backing_overridden); 173 174 /* 175 * Returns an allocated string which is the directory name of this BDS: It 176 * will be used to make relative filenames absolute by prepending this 177 * function's return value to them. 178 */ 179 char *(*bdrv_dirname)(BlockDriverState *bs, Error **errp); 180 181 /* aio */ 182 BlockAIOCB *(*bdrv_aio_preadv)(BlockDriverState *bs, 183 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags, 184 BlockCompletionFunc *cb, void *opaque); 185 BlockAIOCB *(*bdrv_aio_pwritev)(BlockDriverState *bs, 186 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags, 187 BlockCompletionFunc *cb, void *opaque); 188 BlockAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs, 189 BlockCompletionFunc *cb, void *opaque); 190 BlockAIOCB *(*bdrv_aio_pdiscard)(BlockDriverState *bs, 191 int64_t offset, int bytes, 192 BlockCompletionFunc *cb, void *opaque); 193 194 int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs, 195 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); 196 197 /** 198 * @offset: position in bytes to read at 199 * @bytes: number of bytes to read 200 * @qiov: the buffers to fill with read data 201 * @flags: currently unused, always 0 202 * 203 * @offset and @bytes will be a multiple of 'request_alignment', 204 * but the length of individual @qiov elements does not have to 205 * be a multiple. 206 * 207 * @bytes will always equal the total size of @qiov, and will be 208 * no larger than 'max_transfer'. 209 * 210 * The buffer in @qiov may point directly to guest memory. 211 */ 212 int coroutine_fn (*bdrv_co_preadv)(BlockDriverState *bs, 213 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags); 214 int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs, 215 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, int flags); 216 /** 217 * @offset: position in bytes to write at 218 * @bytes: number of bytes to write 219 * @qiov: the buffers containing data to write 220 * @flags: zero or more bits allowed by 'supported_write_flags' 221 * 222 * @offset and @bytes will be a multiple of 'request_alignment', 223 * but the length of individual @qiov elements does not have to 224 * be a multiple. 225 * 226 * @bytes will always equal the total size of @qiov, and will be 227 * no larger than 'max_transfer'. 228 * 229 * The buffer in @qiov may point directly to guest memory. 230 */ 231 int coroutine_fn (*bdrv_co_pwritev)(BlockDriverState *bs, 232 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags); 233 234 /* 235 * Efficiently zero a region of the disk image. Typically an image format 236 * would use a compact metadata representation to implement this. This 237 * function pointer may be NULL or return -ENOSUP and .bdrv_co_writev() 238 * will be called instead. 239 */ 240 int coroutine_fn (*bdrv_co_pwrite_zeroes)(BlockDriverState *bs, 241 int64_t offset, int bytes, BdrvRequestFlags flags); 242 int coroutine_fn (*bdrv_co_pdiscard)(BlockDriverState *bs, 243 int64_t offset, int bytes); 244 245 /* Map [offset, offset + nbytes) range onto a child of @bs to copy from, 246 * and invoke bdrv_co_copy_range_from(child, ...), or invoke 247 * bdrv_co_copy_range_to() if @bs is the leaf child to copy data from. 248 * 249 * See the comment of bdrv_co_copy_range for the parameter and return value 250 * semantics. 251 */ 252 int coroutine_fn (*bdrv_co_copy_range_from)(BlockDriverState *bs, 253 BdrvChild *src, 254 uint64_t offset, 255 BdrvChild *dst, 256 uint64_t dst_offset, 257 uint64_t bytes, 258 BdrvRequestFlags read_flags, 259 BdrvRequestFlags write_flags); 260 261 /* Map [offset, offset + nbytes) range onto a child of bs to copy data to, 262 * and invoke bdrv_co_copy_range_to(child, src, ...), or perform the copy 263 * operation if @bs is the leaf and @src has the same BlockDriver. Return 264 * -ENOTSUP if @bs is the leaf but @src has a different BlockDriver. 265 * 266 * See the comment of bdrv_co_copy_range for the parameter and return value 267 * semantics. 268 */ 269 int coroutine_fn (*bdrv_co_copy_range_to)(BlockDriverState *bs, 270 BdrvChild *src, 271 uint64_t src_offset, 272 BdrvChild *dst, 273 uint64_t dst_offset, 274 uint64_t bytes, 275 BdrvRequestFlags read_flags, 276 BdrvRequestFlags write_flags); 277 278 /* 279 * Building block for bdrv_block_status[_above] and 280 * bdrv_is_allocated[_above]. The driver should answer only 281 * according to the current layer, and should only need to set 282 * BDRV_BLOCK_DATA, BDRV_BLOCK_ZERO, BDRV_BLOCK_OFFSET_VALID, 283 * and/or BDRV_BLOCK_RAW; if the current layer defers to a backing 284 * layer, the result should be 0 (and not BDRV_BLOCK_ZERO). See 285 * block.h for the overall meaning of the bits. As a hint, the 286 * flag want_zero is true if the caller cares more about precise 287 * mappings (favor accurate _OFFSET_VALID/_ZERO) or false for 288 * overall allocation (favor larger *pnum, perhaps by reporting 289 * _DATA instead of _ZERO). The block layer guarantees input 290 * clamped to bdrv_getlength() and aligned to request_alignment, 291 * as well as non-NULL pnum, map, and file; in turn, the driver 292 * must return an error or set pnum to an aligned non-zero value. 293 */ 294 int coroutine_fn (*bdrv_co_block_status)(BlockDriverState *bs, 295 bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum, 296 int64_t *map, BlockDriverState **file); 297 298 /* 299 * Invalidate any cached meta-data. 300 */ 301 void coroutine_fn (*bdrv_co_invalidate_cache)(BlockDriverState *bs, 302 Error **errp); 303 int (*bdrv_inactivate)(BlockDriverState *bs); 304 305 /* 306 * Flushes all data for all layers by calling bdrv_co_flush for underlying 307 * layers, if needed. This function is needed for deterministic 308 * synchronization of the flush finishing callback. 309 */ 310 int coroutine_fn (*bdrv_co_flush)(BlockDriverState *bs); 311 312 /* 313 * Flushes all data that was already written to the OS all the way down to 314 * the disk (for example file-posix.c calls fsync()). 315 */ 316 int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs); 317 318 /* 319 * Flushes all internal caches to the OS. The data may still sit in a 320 * writeback cache of the host OS, but it will survive a crash of the qemu 321 * process. 322 */ 323 int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs); 324 325 /* 326 * Drivers setting this field must be able to work with just a plain 327 * filename with '<protocol_name>:' as a prefix, and no other options. 328 * Options may be extracted from the filename by implementing 329 * bdrv_parse_filename. 330 */ 331 const char *protocol_name; 332 int coroutine_fn (*bdrv_co_truncate)(BlockDriverState *bs, int64_t offset, 333 PreallocMode prealloc, Error **errp); 334 335 int64_t (*bdrv_getlength)(BlockDriverState *bs); 336 bool has_variable_length; 337 int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs); 338 BlockMeasureInfo *(*bdrv_measure)(QemuOpts *opts, BlockDriverState *in_bs, 339 Error **errp); 340 341 int coroutine_fn (*bdrv_co_pwritev_compressed)(BlockDriverState *bs, 342 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov); 343 344 int (*bdrv_snapshot_create)(BlockDriverState *bs, 345 QEMUSnapshotInfo *sn_info); 346 int (*bdrv_snapshot_goto)(BlockDriverState *bs, 347 const char *snapshot_id); 348 int (*bdrv_snapshot_delete)(BlockDriverState *bs, 349 const char *snapshot_id, 350 const char *name, 351 Error **errp); 352 int (*bdrv_snapshot_list)(BlockDriverState *bs, 353 QEMUSnapshotInfo **psn_info); 354 int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, 355 const char *snapshot_id, 356 const char *name, 357 Error **errp); 358 int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi); 359 ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs, 360 Error **errp); 361 362 int coroutine_fn (*bdrv_save_vmstate)(BlockDriverState *bs, 363 QEMUIOVector *qiov, 364 int64_t pos); 365 int coroutine_fn (*bdrv_load_vmstate)(BlockDriverState *bs, 366 QEMUIOVector *qiov, 367 int64_t pos); 368 369 int (*bdrv_change_backing_file)(BlockDriverState *bs, 370 const char *backing_file, const char *backing_fmt); 371 372 /* removable device specific */ 373 bool (*bdrv_is_inserted)(BlockDriverState *bs); 374 void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag); 375 void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked); 376 377 /* to control generic scsi devices */ 378 BlockAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs, 379 unsigned long int req, void *buf, 380 BlockCompletionFunc *cb, void *opaque); 381 int coroutine_fn (*bdrv_co_ioctl)(BlockDriverState *bs, 382 unsigned long int req, void *buf); 383 384 /* List of options for creating images, terminated by name == NULL */ 385 QemuOptsList *create_opts; 386 /* 387 * If this driver supports reopening images this contains a 388 * NULL-terminated list of the runtime options that can be 389 * modified. If an option in this list is unspecified during 390 * reopen then it _must_ be reset to its default value or return 391 * an error. 392 */ 393 const char *const *mutable_opts; 394 395 /* 396 * Returns 0 for completed check, -errno for internal errors. 397 * The check results are stored in result. 398 */ 399 int coroutine_fn (*bdrv_co_check)(BlockDriverState *bs, 400 BdrvCheckResult *result, 401 BdrvCheckMode fix); 402 403 int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts, 404 BlockDriverAmendStatusCB *status_cb, 405 void *cb_opaque, 406 Error **errp); 407 408 void (*bdrv_debug_event)(BlockDriverState *bs, BlkdebugEvent event); 409 410 /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */ 411 int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event, 412 const char *tag); 413 int (*bdrv_debug_remove_breakpoint)(BlockDriverState *bs, 414 const char *tag); 415 int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag); 416 bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag); 417 418 void (*bdrv_refresh_limits)(BlockDriverState *bs, Error **errp); 419 420 /* 421 * Returns 1 if newly created images are guaranteed to contain only 422 * zeros, 0 otherwise. 423 */ 424 int (*bdrv_has_zero_init)(BlockDriverState *bs); 425 426 /* Remove fd handlers, timers, and other event loop callbacks so the event 427 * loop is no longer in use. Called with no in-flight requests and in 428 * depth-first traversal order with parents before child nodes. 429 */ 430 void (*bdrv_detach_aio_context)(BlockDriverState *bs); 431 432 /* Add fd handlers, timers, and other event loop callbacks so I/O requests 433 * can be processed again. Called with no in-flight requests and in 434 * depth-first traversal order with child nodes before parent nodes. 435 */ 436 void (*bdrv_attach_aio_context)(BlockDriverState *bs, 437 AioContext *new_context); 438 439 /* io queue for linux-aio */ 440 void (*bdrv_io_plug)(BlockDriverState *bs); 441 void (*bdrv_io_unplug)(BlockDriverState *bs); 442 443 /** 444 * Try to get @bs's logical and physical block size. 445 * On success, store them in @bsz and return zero. 446 * On failure, return negative errno. 447 */ 448 int (*bdrv_probe_blocksizes)(BlockDriverState *bs, BlockSizes *bsz); 449 /** 450 * Try to get @bs's geometry (cyls, heads, sectors) 451 * On success, store them in @geo and return 0. 452 * On failure return -errno. 453 * Only drivers that want to override guest geometry implement this 454 * callback; see hd_geometry_guess(). 455 */ 456 int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo); 457 458 /** 459 * bdrv_co_drain_begin is called if implemented in the beginning of a 460 * drain operation to drain and stop any internal sources of requests in 461 * the driver. 462 * bdrv_co_drain_end is called if implemented at the end of the drain. 463 * 464 * They should be used by the driver to e.g. manage scheduled I/O 465 * requests, or toggle an internal state. After the end of the drain new 466 * requests will continue normally. 467 */ 468 void coroutine_fn (*bdrv_co_drain_begin)(BlockDriverState *bs); 469 void coroutine_fn (*bdrv_co_drain_end)(BlockDriverState *bs); 470 471 void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child, 472 Error **errp); 473 void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child, 474 Error **errp); 475 476 /** 477 * Informs the block driver that a permission change is intended. The 478 * driver checks whether the change is permissible and may take other 479 * preparations for the change (e.g. get file system locks). This operation 480 * is always followed either by a call to either .bdrv_set_perm or 481 * .bdrv_abort_perm_update. 482 * 483 * Checks whether the requested set of cumulative permissions in @perm 484 * can be granted for accessing @bs and whether no other users are using 485 * permissions other than those given in @shared (both arguments take 486 * BLK_PERM_* bitmasks). 487 * 488 * If both conditions are met, 0 is returned. Otherwise, -errno is returned 489 * and errp is set to an error describing the conflict. 490 */ 491 int (*bdrv_check_perm)(BlockDriverState *bs, uint64_t perm, 492 uint64_t shared, Error **errp); 493 494 /** 495 * Called to inform the driver that the set of cumulative set of used 496 * permissions for @bs has changed to @perm, and the set of sharable 497 * permission to @shared. The driver can use this to propagate changes to 498 * its children (i.e. request permissions only if a parent actually needs 499 * them). 500 * 501 * This function is only invoked after bdrv_check_perm(), so block drivers 502 * may rely on preparations made in their .bdrv_check_perm implementation. 503 */ 504 void (*bdrv_set_perm)(BlockDriverState *bs, uint64_t perm, uint64_t shared); 505 506 /* 507 * Called to inform the driver that after a previous bdrv_check_perm() 508 * call, the permission update is not performed and any preparations made 509 * for it (e.g. taken file locks) need to be undone. 510 * 511 * This function can be called even for nodes that never saw a 512 * bdrv_check_perm() call. It is a no-op then. 513 */ 514 void (*bdrv_abort_perm_update)(BlockDriverState *bs); 515 516 /** 517 * Returns in @nperm and @nshared the permissions that the driver for @bs 518 * needs on its child @c, based on the cumulative permissions requested by 519 * the parents in @parent_perm and @parent_shared. 520 * 521 * If @c is NULL, return the permissions for attaching a new child for the 522 * given @role. 523 * 524 * If @reopen_queue is non-NULL, don't return the currently needed 525 * permissions, but those that will be needed after applying the 526 * @reopen_queue. 527 */ 528 void (*bdrv_child_perm)(BlockDriverState *bs, BdrvChild *c, 529 const BdrvChildRole *role, 530 BlockReopenQueue *reopen_queue, 531 uint64_t parent_perm, uint64_t parent_shared, 532 uint64_t *nperm, uint64_t *nshared); 533 534 /** 535 * Bitmaps should be marked as 'IN_USE' in the image on reopening image 536 * as rw. This handler should realize it. It also should unset readonly 537 * field of BlockDirtyBitmap's in case of success. 538 */ 539 int (*bdrv_reopen_bitmaps_rw)(BlockDriverState *bs, Error **errp); 540 bool (*bdrv_can_store_new_dirty_bitmap)(BlockDriverState *bs, 541 const char *name, 542 uint32_t granularity, 543 Error **errp); 544 void (*bdrv_remove_persistent_dirty_bitmap)(BlockDriverState *bs, 545 const char *name, 546 Error **errp); 547 548 /** 549 * Register/unregister a buffer for I/O. For example, when the driver is 550 * interested to know the memory areas that will later be used in iovs, so 551 * that it can do IOMMU mapping with VFIO etc., in order to get better 552 * performance. In the case of VFIO drivers, this callback is used to do 553 * DMA mapping for hot buffers. 554 */ 555 void (*bdrv_register_buf)(BlockDriverState *bs, void *host, size_t size); 556 void (*bdrv_unregister_buf)(BlockDriverState *bs, void *host); 557 QLIST_ENTRY(BlockDriver) list; 558 559 /* Pointer to a NULL-terminated array of names of strong options 560 * that can be specified for bdrv_open(). A strong option is one 561 * that changes the data of a BDS. 562 * If this pointer is NULL, the array is considered empty. 563 * "filename" and "driver" are always considered strong. */ 564 const char *const *strong_runtime_opts; 565 }; 566 567 typedef struct BlockLimits { 568 /* Alignment requirement, in bytes, for offset/length of I/O 569 * requests. Must be a power of 2 less than INT_MAX; defaults to 570 * 1 for drivers with modern byte interfaces, and to 512 571 * otherwise. */ 572 uint32_t request_alignment; 573 574 /* Maximum number of bytes that can be discarded at once (since it 575 * is signed, it must be < 2G, if set). Must be multiple of 576 * pdiscard_alignment, but need not be power of 2. May be 0 if no 577 * inherent 32-bit limit */ 578 int32_t max_pdiscard; 579 580 /* Optimal alignment for discard requests in bytes. A power of 2 581 * is best but not mandatory. Must be a multiple of 582 * bl.request_alignment, and must be less than max_pdiscard if 583 * that is set. May be 0 if bl.request_alignment is good enough */ 584 uint32_t pdiscard_alignment; 585 586 /* Maximum number of bytes that can zeroized at once (since it is 587 * signed, it must be < 2G, if set). Must be multiple of 588 * pwrite_zeroes_alignment. May be 0 if no inherent 32-bit limit */ 589 int32_t max_pwrite_zeroes; 590 591 /* Optimal alignment for write zeroes requests in bytes. A power 592 * of 2 is best but not mandatory. Must be a multiple of 593 * bl.request_alignment, and must be less than max_pwrite_zeroes 594 * if that is set. May be 0 if bl.request_alignment is good 595 * enough */ 596 uint32_t pwrite_zeroes_alignment; 597 598 /* Optimal transfer length in bytes. A power of 2 is best but not 599 * mandatory. Must be a multiple of bl.request_alignment, or 0 if 600 * no preferred size */ 601 uint32_t opt_transfer; 602 603 /* Maximal transfer length in bytes. Need not be power of 2, but 604 * must be multiple of opt_transfer and bl.request_alignment, or 0 605 * for no 32-bit limit. For now, anything larger than INT_MAX is 606 * clamped down. */ 607 uint32_t max_transfer; 608 609 /* memory alignment, in bytes so that no bounce buffer is needed */ 610 size_t min_mem_alignment; 611 612 /* memory alignment, in bytes, for bounce buffer */ 613 size_t opt_mem_alignment; 614 615 /* maximum number of iovec elements */ 616 int max_iov; 617 } BlockLimits; 618 619 typedef struct BdrvOpBlocker BdrvOpBlocker; 620 621 typedef struct BdrvAioNotifier { 622 void (*attached_aio_context)(AioContext *new_context, void *opaque); 623 void (*detach_aio_context)(void *opaque); 624 625 void *opaque; 626 bool deleted; 627 628 QLIST_ENTRY(BdrvAioNotifier) list; 629 } BdrvAioNotifier; 630 631 struct BdrvChildRole { 632 /* If true, bdrv_replace_node() doesn't change the node this BdrvChild 633 * points to. */ 634 bool stay_at_node; 635 636 /* If true, the parent is a BlockDriverState and bdrv_next_all_states() 637 * will return it. This information is used for drain_all, where every node 638 * will be drained separately, so the drain only needs to be propagated to 639 * non-BDS parents. */ 640 bool parent_is_bds; 641 642 void (*inherit_options)(int *child_flags, QDict *child_options, 643 int parent_flags, QDict *parent_options); 644 645 void (*change_media)(BdrvChild *child, bool load); 646 void (*resize)(BdrvChild *child); 647 648 /* Returns a name that is supposedly more useful for human users than the 649 * node name for identifying the node in question (in particular, a BB 650 * name), or NULL if the parent can't provide a better name. */ 651 const char *(*get_name)(BdrvChild *child); 652 653 /* Returns a malloced string that describes the parent of the child for a 654 * human reader. This could be a node-name, BlockBackend name, qdev ID or 655 * QOM path of the device owning the BlockBackend, job type and ID etc. The 656 * caller is responsible for freeing the memory. */ 657 char *(*get_parent_desc)(BdrvChild *child); 658 659 /* 660 * If this pair of functions is implemented, the parent doesn't issue new 661 * requests after returning from .drained_begin() until .drained_end() is 662 * called. 663 * 664 * These functions must not change the graph (and therefore also must not 665 * call aio_poll(), which could change the graph indirectly). 666 * 667 * Note that this can be nested. If drained_begin() was called twice, new 668 * I/O is allowed only after drained_end() was called twice, too. 669 */ 670 void (*drained_begin)(BdrvChild *child); 671 void (*drained_end)(BdrvChild *child); 672 673 /* 674 * Returns whether the parent has pending requests for the child. This 675 * callback is polled after .drained_begin() has been called until all 676 * activity on the child has stopped. 677 */ 678 bool (*drained_poll)(BdrvChild *child); 679 680 /* Notifies the parent that the child has been activated/inactivated (e.g. 681 * when migration is completing) and it can start/stop requesting 682 * permissions and doing I/O on it. */ 683 void (*activate)(BdrvChild *child, Error **errp); 684 int (*inactivate)(BdrvChild *child); 685 686 void (*attach)(BdrvChild *child); 687 void (*detach)(BdrvChild *child); 688 689 /* Notifies the parent that the filename of its child has changed (e.g. 690 * because the direct child was removed from the backing chain), so that it 691 * can update its reference. */ 692 int (*update_filename)(BdrvChild *child, BlockDriverState *new_base, 693 const char *filename, Error **errp); 694 695 bool (*can_set_aio_ctx)(BdrvChild *child, AioContext *ctx, 696 GSList **ignore, Error **errp); 697 void (*set_aio_ctx)(BdrvChild *child, AioContext *ctx, GSList **ignore); 698 }; 699 700 extern const BdrvChildRole child_file; 701 extern const BdrvChildRole child_format; 702 extern const BdrvChildRole child_backing; 703 704 struct BdrvChild { 705 BlockDriverState *bs; 706 char *name; 707 const BdrvChildRole *role; 708 void *opaque; 709 710 /** 711 * Granted permissions for operating on this BdrvChild (BLK_PERM_* bitmask) 712 */ 713 uint64_t perm; 714 715 /** 716 * Permissions that can still be granted to other users of @bs while this 717 * BdrvChild is still attached to it. (BLK_PERM_* bitmask) 718 */ 719 uint64_t shared_perm; 720 721 /* backup of permissions during permission update procedure */ 722 bool has_backup_perm; 723 uint64_t backup_perm; 724 uint64_t backup_shared_perm; 725 726 /* 727 * This link is frozen: the child can neither be replaced nor 728 * detached from the parent. 729 */ 730 bool frozen; 731 732 QLIST_ENTRY(BdrvChild) next; 733 QLIST_ENTRY(BdrvChild) next_parent; 734 }; 735 736 /* 737 * Note: the function bdrv_append() copies and swaps contents of 738 * BlockDriverStates, so if you add new fields to this struct, please 739 * inspect bdrv_append() to determine if the new fields need to be 740 * copied as well. 741 */ 742 struct BlockDriverState { 743 /* Protected by big QEMU lock or read-only after opening. No special 744 * locking needed during I/O... 745 */ 746 int open_flags; /* flags used to open the file, re-used for re-open */ 747 bool read_only; /* if true, the media is read only */ 748 bool encrypted; /* if true, the media is encrypted */ 749 bool sg; /* if true, the device is a /dev/sg* */ 750 bool probed; /* if true, format was probed rather than specified */ 751 bool force_share; /* if true, always allow all shared permissions */ 752 bool implicit; /* if true, this filter node was automatically inserted */ 753 754 BlockDriver *drv; /* NULL means no media */ 755 void *opaque; 756 757 AioContext *aio_context; /* event loop used for fd handlers, timers, etc */ 758 /* long-running tasks intended to always use the same AioContext as this 759 * BDS may register themselves in this list to be notified of changes 760 * regarding this BDS's context */ 761 QLIST_HEAD(, BdrvAioNotifier) aio_notifiers; 762 bool walking_aio_notifiers; /* to make removal during iteration safe */ 763 764 char filename[PATH_MAX]; 765 char backing_file[PATH_MAX]; /* if non zero, the image is a diff of 766 this file image */ 767 /* The backing filename indicated by the image header; if we ever 768 * open this file, then this is replaced by the resulting BDS's 769 * filename (i.e. after a bdrv_refresh_filename() run). */ 770 char auto_backing_file[PATH_MAX]; 771 char backing_format[16]; /* if non-zero and backing_file exists */ 772 773 QDict *full_open_options; 774 char exact_filename[PATH_MAX]; 775 776 BdrvChild *backing; 777 BdrvChild *file; 778 779 /* I/O Limits */ 780 BlockLimits bl; 781 782 /* Flags honored during pwrite (so far: BDRV_REQ_FUA, 783 * BDRV_REQ_WRITE_UNCHANGED). 784 * If a driver does not support BDRV_REQ_WRITE_UNCHANGED, those 785 * writes will be issued as normal writes without the flag set. 786 * This is important to note for drivers that do not explicitly 787 * request a WRITE permission for their children and instead take 788 * the same permissions as their parent did (this is commonly what 789 * block filters do). Such drivers have to be aware that the 790 * parent may have taken a WRITE_UNCHANGED permission only and is 791 * issuing such requests. Drivers either must make sure that 792 * these requests do not result in plain WRITE accesses (usually 793 * by supporting BDRV_REQ_WRITE_UNCHANGED, and then forwarding 794 * every incoming write request as-is, including potentially that 795 * flag), or they have to explicitly take the WRITE permission for 796 * their children. */ 797 unsigned int supported_write_flags; 798 /* Flags honored during pwrite_zeroes (so far: BDRV_REQ_FUA, 799 * BDRV_REQ_MAY_UNMAP, BDRV_REQ_WRITE_UNCHANGED) */ 800 unsigned int supported_zero_flags; 801 802 /* the following member gives a name to every node on the bs graph. */ 803 char node_name[32]; 804 /* element of the list of named nodes building the graph */ 805 QTAILQ_ENTRY(BlockDriverState) node_list; 806 /* element of the list of all BlockDriverStates (all_bdrv_states) */ 807 QTAILQ_ENTRY(BlockDriverState) bs_list; 808 /* element of the list of monitor-owned BDS */ 809 QTAILQ_ENTRY(BlockDriverState) monitor_list; 810 int refcnt; 811 812 /* operation blockers */ 813 QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX]; 814 815 /* The node that this node inherited default options from (and a reopen on 816 * which can affect this node by changing these defaults). This is always a 817 * parent node of this node. */ 818 BlockDriverState *inherits_from; 819 QLIST_HEAD(, BdrvChild) children; 820 QLIST_HEAD(, BdrvChild) parents; 821 822 QDict *options; 823 QDict *explicit_options; 824 BlockdevDetectZeroesOptions detect_zeroes; 825 826 /* The error object in use for blocking operations on backing_hd */ 827 Error *backing_blocker; 828 829 /* Protected by AioContext lock */ 830 831 /* If we are reading a disk image, give its size in sectors. 832 * Generally read-only; it is written to by load_snapshot and 833 * save_snaphost, but the block layer is quiescent during those. 834 */ 835 int64_t total_sectors; 836 837 /* Callback before write request is processed */ 838 NotifierWithReturnList before_write_notifiers; 839 840 /* threshold limit for writes, in bytes. "High water mark". */ 841 uint64_t write_threshold_offset; 842 NotifierWithReturn write_threshold_notifier; 843 844 /* Writing to the list requires the BQL _and_ the dirty_bitmap_mutex. 845 * Reading from the list can be done with either the BQL or the 846 * dirty_bitmap_mutex. Modifying a bitmap only requires 847 * dirty_bitmap_mutex. */ 848 QemuMutex dirty_bitmap_mutex; 849 QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps; 850 851 /* Offset after the highest byte written to */ 852 Stat64 wr_highest_offset; 853 854 /* If true, copy read backing sectors into image. Can be >1 if more 855 * than one client has requested copy-on-read. Accessed with atomic 856 * ops. 857 */ 858 int copy_on_read; 859 860 /* number of in-flight requests; overall and serialising. 861 * Accessed with atomic ops. 862 */ 863 unsigned int in_flight; 864 unsigned int serialising_in_flight; 865 866 /* counter for nested bdrv_io_plug. 867 * Accessed with atomic ops. 868 */ 869 unsigned io_plugged; 870 871 /* do we need to tell the quest if we have a volatile write cache? */ 872 int enable_write_cache; 873 874 /* Accessed with atomic ops. */ 875 int quiesce_counter; 876 int recursive_quiesce_counter; 877 878 unsigned int write_gen; /* Current data generation */ 879 880 /* Protected by reqs_lock. */ 881 CoMutex reqs_lock; 882 QLIST_HEAD(, BdrvTrackedRequest) tracked_requests; 883 CoQueue flush_queue; /* Serializing flush queue */ 884 bool active_flush_req; /* Flush request in flight? */ 885 886 /* Only read/written by whoever has set active_flush_req to true. */ 887 unsigned int flushed_gen; /* Flushed write generation */ 888 }; 889 890 struct BlockBackendRootState { 891 int open_flags; 892 bool read_only; 893 BlockdevDetectZeroesOptions detect_zeroes; 894 }; 895 896 typedef enum BlockMirrorBackingMode { 897 /* Reuse the existing backing chain from the source for the target. 898 * - sync=full: Set backing BDS to NULL. 899 * - sync=top: Use source's backing BDS. 900 * - sync=none: Use source as the backing BDS. */ 901 MIRROR_SOURCE_BACKING_CHAIN, 902 903 /* Open the target's backing chain completely anew */ 904 MIRROR_OPEN_BACKING_CHAIN, 905 906 /* Do not change the target's backing BDS after job completion */ 907 MIRROR_LEAVE_BACKING_CHAIN, 908 } BlockMirrorBackingMode; 909 910 static inline BlockDriverState *backing_bs(BlockDriverState *bs) 911 { 912 return bs->backing ? bs->backing->bs : NULL; 913 } 914 915 916 /* Essential block drivers which must always be statically linked into qemu, and 917 * which therefore can be accessed without using bdrv_find_format() */ 918 extern BlockDriver bdrv_file; 919 extern BlockDriver bdrv_raw; 920 extern BlockDriver bdrv_qcow2; 921 922 int coroutine_fn bdrv_co_preadv(BdrvChild *child, 923 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 924 BdrvRequestFlags flags); 925 int coroutine_fn bdrv_co_pwritev(BdrvChild *child, 926 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 927 BdrvRequestFlags flags); 928 929 static inline int coroutine_fn bdrv_co_pread(BdrvChild *child, 930 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags) 931 { 932 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); 933 934 return bdrv_co_preadv(child, offset, bytes, &qiov, flags); 935 } 936 937 static inline int coroutine_fn bdrv_co_pwrite(BdrvChild *child, 938 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags) 939 { 940 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); 941 942 return bdrv_co_pwritev(child, offset, bytes, &qiov, flags); 943 } 944 945 extern unsigned int bdrv_drain_all_count; 946 void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent); 947 void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent); 948 949 int get_tmp_filename(char *filename, int size); 950 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, 951 const char *filename); 952 953 void bdrv_parse_filename_strip_prefix(const char *filename, const char *prefix, 954 QDict *options); 955 956 957 /** 958 * bdrv_add_before_write_notifier: 959 * 960 * Register a callback that is invoked before write requests are processed but 961 * after any throttling or waiting for overlapping requests. 962 */ 963 void bdrv_add_before_write_notifier(BlockDriverState *bs, 964 NotifierWithReturn *notifier); 965 966 /** 967 * bdrv_add_aio_context_notifier: 968 * 969 * If a long-running job intends to be always run in the same AioContext as a 970 * certain BDS, it may use this function to be notified of changes regarding the 971 * association of the BDS to an AioContext. 972 * 973 * attached_aio_context() is called after the target BDS has been attached to a 974 * new AioContext; detach_aio_context() is called before the target BDS is being 975 * detached from its old AioContext. 976 */ 977 void bdrv_add_aio_context_notifier(BlockDriverState *bs, 978 void (*attached_aio_context)(AioContext *new_context, void *opaque), 979 void (*detach_aio_context)(void *opaque), void *opaque); 980 981 /** 982 * bdrv_remove_aio_context_notifier: 983 * 984 * Unsubscribe of change notifications regarding the BDS's AioContext. The 985 * parameters given here have to be the same as those given to 986 * bdrv_add_aio_context_notifier(). 987 */ 988 void bdrv_remove_aio_context_notifier(BlockDriverState *bs, 989 void (*aio_context_attached)(AioContext *, 990 void *), 991 void (*aio_context_detached)(void *), 992 void *opaque); 993 994 /** 995 * bdrv_wakeup: 996 * @bs: The BlockDriverState for which an I/O operation has been completed. 997 * 998 * Wake up the main thread if it is waiting on BDRV_POLL_WHILE. During 999 * synchronous I/O on a BlockDriverState that is attached to another 1000 * I/O thread, the main thread lets the I/O thread's event loop run, 1001 * waiting for the I/O operation to complete. A bdrv_wakeup will wake 1002 * up the main thread if necessary. 1003 * 1004 * Manual calls to bdrv_wakeup are rarely necessary, because 1005 * bdrv_dec_in_flight already calls it. 1006 */ 1007 void bdrv_wakeup(BlockDriverState *bs); 1008 1009 #ifdef _WIN32 1010 int is_windows_drive(const char *filename); 1011 #endif 1012 1013 /** 1014 * stream_start: 1015 * @job_id: The id of the newly-created job, or %NULL to use the 1016 * device name of @bs. 1017 * @bs: Block device to operate on. 1018 * @base: Block device that will become the new base, or %NULL to 1019 * flatten the whole backing file chain onto @bs. 1020 * @backing_file_str: The file name that will be written to @bs as the 1021 * the new backing file if the job completes. Ignored if @base is %NULL. 1022 * @creation_flags: Flags that control the behavior of the Job lifetime. 1023 * See @BlockJobCreateFlags 1024 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1025 * @on_error: The action to take upon error. 1026 * @errp: Error object. 1027 * 1028 * Start a streaming operation on @bs. Clusters that are unallocated 1029 * in @bs, but allocated in any image between @base and @bs (both 1030 * exclusive) will be written to @bs. At the end of a successful 1031 * streaming job, the backing file of @bs will be changed to 1032 * @backing_file_str in the written image and to @base in the live 1033 * BlockDriverState. 1034 */ 1035 void stream_start(const char *job_id, BlockDriverState *bs, 1036 BlockDriverState *base, const char *backing_file_str, 1037 int creation_flags, int64_t speed, 1038 BlockdevOnError on_error, Error **errp); 1039 1040 /** 1041 * commit_start: 1042 * @job_id: The id of the newly-created job, or %NULL to use the 1043 * device name of @bs. 1044 * @bs: Active block device. 1045 * @top: Top block device to be committed. 1046 * @base: Block device that will be written into, and become the new top. 1047 * @creation_flags: Flags that control the behavior of the Job lifetime. 1048 * See @BlockJobCreateFlags 1049 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1050 * @on_error: The action to take upon error. 1051 * @backing_file_str: String to use as the backing file in @top's overlay 1052 * @filter_node_name: The node name that should be assigned to the filter 1053 * driver that the commit job inserts into the graph above @top. NULL means 1054 * that a node name should be autogenerated. 1055 * @errp: Error object. 1056 * 1057 */ 1058 void commit_start(const char *job_id, BlockDriverState *bs, 1059 BlockDriverState *base, BlockDriverState *top, 1060 int creation_flags, int64_t speed, 1061 BlockdevOnError on_error, const char *backing_file_str, 1062 const char *filter_node_name, Error **errp); 1063 /** 1064 * commit_active_start: 1065 * @job_id: The id of the newly-created job, or %NULL to use the 1066 * device name of @bs. 1067 * @bs: Active block device to be committed. 1068 * @base: Block device that will be written into, and become the new top. 1069 * @creation_flags: Flags that control the behavior of the Job lifetime. 1070 * See @BlockJobCreateFlags 1071 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1072 * @on_error: The action to take upon error. 1073 * @filter_node_name: The node name that should be assigned to the filter 1074 * driver that the commit job inserts into the graph above @bs. NULL means that 1075 * a node name should be autogenerated. 1076 * @cb: Completion function for the job. 1077 * @opaque: Opaque pointer value passed to @cb. 1078 * @auto_complete: Auto complete the job. 1079 * @errp: Error object. 1080 * 1081 */ 1082 BlockJob *commit_active_start(const char *job_id, BlockDriverState *bs, 1083 BlockDriverState *base, int creation_flags, 1084 int64_t speed, BlockdevOnError on_error, 1085 const char *filter_node_name, 1086 BlockCompletionFunc *cb, void *opaque, 1087 bool auto_complete, Error **errp); 1088 /* 1089 * mirror_start: 1090 * @job_id: The id of the newly-created job, or %NULL to use the 1091 * device name of @bs. 1092 * @bs: Block device to operate on. 1093 * @target: Block device to write to. 1094 * @replaces: Block graph node name to replace once the mirror is done. Can 1095 * only be used when full mirroring is selected. 1096 * @creation_flags: Flags that control the behavior of the Job lifetime. 1097 * See @BlockJobCreateFlags 1098 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1099 * @granularity: The chosen granularity for the dirty bitmap. 1100 * @buf_size: The amount of data that can be in flight at one time. 1101 * @mode: Whether to collapse all images in the chain to the target. 1102 * @backing_mode: How to establish the target's backing chain after completion. 1103 * @on_source_error: The action to take upon error reading from the source. 1104 * @on_target_error: The action to take upon error writing to the target. 1105 * @unmap: Whether to unmap target where source sectors only contain zeroes. 1106 * @filter_node_name: The node name that should be assigned to the filter 1107 * driver that the mirror job inserts into the graph above @bs. NULL means that 1108 * a node name should be autogenerated. 1109 * @copy_mode: When to trigger writes to the target. 1110 * @errp: Error object. 1111 * 1112 * Start a mirroring operation on @bs. Clusters that are allocated 1113 * in @bs will be written to @target until the job is cancelled or 1114 * manually completed. At the end of a successful mirroring job, 1115 * @bs will be switched to read from @target. 1116 */ 1117 void mirror_start(const char *job_id, BlockDriverState *bs, 1118 BlockDriverState *target, const char *replaces, 1119 int creation_flags, int64_t speed, 1120 uint32_t granularity, int64_t buf_size, 1121 MirrorSyncMode mode, BlockMirrorBackingMode backing_mode, 1122 BlockdevOnError on_source_error, 1123 BlockdevOnError on_target_error, 1124 bool unmap, const char *filter_node_name, 1125 MirrorCopyMode copy_mode, Error **errp); 1126 1127 /* 1128 * backup_job_create: 1129 * @job_id: The id of the newly-created job, or %NULL to use the 1130 * device name of @bs. 1131 * @bs: Block device to operate on. 1132 * @target: Block device to write to. 1133 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1134 * @sync_mode: What parts of the disk image should be copied to the destination. 1135 * @sync_bitmap: The dirty bitmap if sync_mode is MIRROR_SYNC_MODE_INCREMENTAL. 1136 * @on_source_error: The action to take upon error reading from the source. 1137 * @on_target_error: The action to take upon error writing to the target. 1138 * @creation_flags: Flags that control the behavior of the Job lifetime. 1139 * See @BlockJobCreateFlags 1140 * @cb: Completion function for the job. 1141 * @opaque: Opaque pointer value passed to @cb. 1142 * @txn: Transaction that this job is part of (may be NULL). 1143 * 1144 * Create a backup operation on @bs. Clusters in @bs are written to @target 1145 * until the job is cancelled or manually completed. 1146 */ 1147 BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, 1148 BlockDriverState *target, int64_t speed, 1149 MirrorSyncMode sync_mode, 1150 BdrvDirtyBitmap *sync_bitmap, 1151 bool compress, 1152 BlockdevOnError on_source_error, 1153 BlockdevOnError on_target_error, 1154 int creation_flags, 1155 BlockCompletionFunc *cb, void *opaque, 1156 JobTxn *txn, Error **errp); 1157 1158 void hmp_drive_add_node(Monitor *mon, const char *optstr); 1159 1160 BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, 1161 const char *child_name, 1162 const BdrvChildRole *child_role, 1163 AioContext *ctx, 1164 uint64_t perm, uint64_t shared_perm, 1165 void *opaque, Error **errp); 1166 void bdrv_root_unref_child(BdrvChild *child); 1167 1168 /** 1169 * Sets a BdrvChild's permissions. Avoid if the parent is a BDS; use 1170 * bdrv_child_refresh_perms() instead and make the parent's 1171 * .bdrv_child_perm() implementation return the correct values. 1172 */ 1173 int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, 1174 Error **errp); 1175 1176 /** 1177 * Calls bs->drv->bdrv_child_perm() and updates the child's permission 1178 * masks with the result. 1179 * Drivers should invoke this function whenever an event occurs that 1180 * makes their .bdrv_child_perm() implementation return different 1181 * values than before, but which will not result in the block layer 1182 * automatically refreshing the permissions. 1183 */ 1184 int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp); 1185 1186 /* Default implementation for BlockDriver.bdrv_child_perm() that can be used by 1187 * block filters: Forward CONSISTENT_READ, WRITE, WRITE_UNCHANGED and RESIZE to 1188 * all children */ 1189 void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, 1190 const BdrvChildRole *role, 1191 BlockReopenQueue *reopen_queue, 1192 uint64_t perm, uint64_t shared, 1193 uint64_t *nperm, uint64_t *nshared); 1194 1195 /* Default implementation for BlockDriver.bdrv_child_perm() that can be used by 1196 * (non-raw) image formats: Like above for bs->backing, but for bs->file it 1197 * requires WRITE | RESIZE for read-write images, always requires 1198 * CONSISTENT_READ and doesn't share WRITE. */ 1199 void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c, 1200 const BdrvChildRole *role, 1201 BlockReopenQueue *reopen_queue, 1202 uint64_t perm, uint64_t shared, 1203 uint64_t *nperm, uint64_t *nshared); 1204 1205 /* 1206 * Default implementation for drivers to pass bdrv_co_block_status() to 1207 * their file. 1208 */ 1209 int coroutine_fn bdrv_co_block_status_from_file(BlockDriverState *bs, 1210 bool want_zero, 1211 int64_t offset, 1212 int64_t bytes, 1213 int64_t *pnum, 1214 int64_t *map, 1215 BlockDriverState **file); 1216 /* 1217 * Default implementation for drivers to pass bdrv_co_block_status() to 1218 * their backing file. 1219 */ 1220 int coroutine_fn bdrv_co_block_status_from_backing(BlockDriverState *bs, 1221 bool want_zero, 1222 int64_t offset, 1223 int64_t bytes, 1224 int64_t *pnum, 1225 int64_t *map, 1226 BlockDriverState **file); 1227 const char *bdrv_get_parent_name(const BlockDriverState *bs); 1228 void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp); 1229 bool blk_dev_has_removable_media(BlockBackend *blk); 1230 bool blk_dev_has_tray(BlockBackend *blk); 1231 void blk_dev_eject_request(BlockBackend *blk, bool force); 1232 bool blk_dev_is_tray_open(BlockBackend *blk); 1233 bool blk_dev_is_medium_locked(BlockBackend *blk); 1234 1235 void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes); 1236 1237 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out); 1238 void bdrv_restore_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *backup); 1239 1240 void bdrv_inc_in_flight(BlockDriverState *bs); 1241 void bdrv_dec_in_flight(BlockDriverState *bs); 1242 1243 void blockdev_close_all_bdrv_states(void); 1244 1245 int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, uint64_t src_offset, 1246 BdrvChild *dst, uint64_t dst_offset, 1247 uint64_t bytes, 1248 BdrvRequestFlags read_flags, 1249 BdrvRequestFlags write_flags); 1250 int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, uint64_t src_offset, 1251 BdrvChild *dst, uint64_t dst_offset, 1252 uint64_t bytes, 1253 BdrvRequestFlags read_flags, 1254 BdrvRequestFlags write_flags); 1255 1256 int refresh_total_sectors(BlockDriverState *bs, int64_t hint); 1257 1258 #endif /* BLOCK_INT_H */ 1259