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/throttle.h" 37 38 #define BLOCK_FLAG_LAZY_REFCOUNTS 8 39 40 #define BLOCK_OPT_SIZE "size" 41 #define BLOCK_OPT_ENCRYPT "encryption" 42 #define BLOCK_OPT_ENCRYPT_FORMAT "encrypt.format" 43 #define BLOCK_OPT_COMPAT6 "compat6" 44 #define BLOCK_OPT_HWVERSION "hwversion" 45 #define BLOCK_OPT_BACKING_FILE "backing_file" 46 #define BLOCK_OPT_BACKING_FMT "backing_fmt" 47 #define BLOCK_OPT_CLUSTER_SIZE "cluster_size" 48 #define BLOCK_OPT_TABLE_SIZE "table_size" 49 #define BLOCK_OPT_PREALLOC "preallocation" 50 #define BLOCK_OPT_SUBFMT "subformat" 51 #define BLOCK_OPT_COMPAT_LEVEL "compat" 52 #define BLOCK_OPT_LAZY_REFCOUNTS "lazy_refcounts" 53 #define BLOCK_OPT_ADAPTER_TYPE "adapter_type" 54 #define BLOCK_OPT_REDUNDANCY "redundancy" 55 #define BLOCK_OPT_NOCOW "nocow" 56 #define BLOCK_OPT_OBJECT_SIZE "object_size" 57 #define BLOCK_OPT_REFCOUNT_BITS "refcount_bits" 58 #define BLOCK_OPT_DATA_FILE "data_file" 59 #define BLOCK_OPT_DATA_FILE_RAW "data_file_raw" 60 61 #define BLOCK_PROBE_BUF_SIZE 512 62 63 enum BdrvTrackedRequestType { 64 BDRV_TRACKED_READ, 65 BDRV_TRACKED_WRITE, 66 BDRV_TRACKED_DISCARD, 67 BDRV_TRACKED_TRUNCATE, 68 }; 69 70 typedef struct BdrvTrackedRequest { 71 BlockDriverState *bs; 72 int64_t offset; 73 uint64_t bytes; 74 enum BdrvTrackedRequestType type; 75 76 bool serialising; 77 int64_t overlap_offset; 78 uint64_t 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. Block filters pass 92 * certain callbacks that refer to data (see block.c) to their bs->file if 93 * the driver doesn't implement them. Drivers that do not wish to forward 94 * must implement them and return -ENOTSUP. 95 */ 96 bool is_filter; 97 /* for snapshots block filter like Quorum can implement the 98 * following recursive callback. 99 * It's purpose is to recurse on the filter children while calling 100 * bdrv_recurse_is_first_non_filter on them. 101 * For a sample implementation look in the future Quorum block filter. 102 */ 103 bool (*bdrv_recurse_is_first_non_filter)(BlockDriverState *bs, 104 BlockDriverState *candidate); 105 106 int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename); 107 int (*bdrv_probe_device)(const char *filename); 108 109 /* Any driver implementing this callback is expected to be able to handle 110 * NULL file names in its .bdrv_open() implementation */ 111 void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp); 112 /* Drivers not implementing bdrv_parse_filename nor bdrv_open should have 113 * this field set to true, except ones that are defined only by their 114 * child's bs. 115 * An example of the last type will be the quorum block driver. 116 */ 117 bool bdrv_needs_filename; 118 119 /* Set if a driver can support backing files */ 120 bool supports_backing; 121 122 /* For handling image reopen for split or non-split files */ 123 int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state, 124 BlockReopenQueue *queue, Error **errp); 125 void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state); 126 void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state); 127 void (*bdrv_join_options)(QDict *options, QDict *old_options); 128 129 int (*bdrv_open)(BlockDriverState *bs, QDict *options, int flags, 130 Error **errp); 131 132 /* Protocol drivers should implement this instead of bdrv_open */ 133 int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags, 134 Error **errp); 135 void (*bdrv_close)(BlockDriverState *bs); 136 int coroutine_fn (*bdrv_co_create)(BlockdevCreateOptions *opts, 137 Error **errp); 138 int coroutine_fn (*bdrv_co_create_opts)(const char *filename, 139 QemuOpts *opts, 140 Error **errp); 141 int (*bdrv_make_empty)(BlockDriverState *bs); 142 143 /* 144 * Refreshes the bs->exact_filename field. If that is impossible, 145 * bs->exact_filename has to be left empty. 146 */ 147 void (*bdrv_refresh_filename)(BlockDriverState *bs); 148 149 /* 150 * Gathers the open options for all children into @target. 151 * A simple format driver (without backing file support) might 152 * implement this function like this: 153 * 154 * QINCREF(bs->file->bs->full_open_options); 155 * qdict_put(target, "file", bs->file->bs->full_open_options); 156 * 157 * If not specified, the generic implementation will simply put 158 * all children's options under their respective name. 159 * 160 * @backing_overridden is true when bs->backing seems not to be 161 * the child that would result from opening bs->backing_file. 162 * Therefore, if it is true, the backing child's options should be 163 * gathered; otherwise, there is no need since the backing child 164 * is the one implied by the image header. 165 * 166 * Note that ideally this function would not be needed. Every 167 * block driver which implements it is probably doing something 168 * shady regarding its runtime option structure. 169 */ 170 void (*bdrv_gather_child_options)(BlockDriverState *bs, QDict *target, 171 bool backing_overridden); 172 173 /* 174 * Returns an allocated string which is the directory name of this BDS: It 175 * will be used to make relative filenames absolute by prepending this 176 * function's return value to them. 177 */ 178 char *(*bdrv_dirname)(BlockDriverState *bs, Error **errp); 179 180 /* aio */ 181 BlockAIOCB *(*bdrv_aio_preadv)(BlockDriverState *bs, 182 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags, 183 BlockCompletionFunc *cb, void *opaque); 184 BlockAIOCB *(*bdrv_aio_pwritev)(BlockDriverState *bs, 185 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags, 186 BlockCompletionFunc *cb, void *opaque); 187 BlockAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs, 188 BlockCompletionFunc *cb, void *opaque); 189 BlockAIOCB *(*bdrv_aio_pdiscard)(BlockDriverState *bs, 190 int64_t offset, int bytes, 191 BlockCompletionFunc *cb, void *opaque); 192 193 int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs, 194 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); 195 196 /** 197 * @offset: position in bytes to read at 198 * @bytes: number of bytes to read 199 * @qiov: the buffers to fill with read data 200 * @flags: currently unused, always 0 201 * 202 * @offset and @bytes will be a multiple of 'request_alignment', 203 * but the length of individual @qiov elements does not have to 204 * be a multiple. 205 * 206 * @bytes will always equal the total size of @qiov, and will be 207 * no larger than 'max_transfer'. 208 * 209 * The buffer in @qiov may point directly to guest memory. 210 */ 211 int coroutine_fn (*bdrv_co_preadv)(BlockDriverState *bs, 212 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags); 213 int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs, 214 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, int flags); 215 /** 216 * @offset: position in bytes to write at 217 * @bytes: number of bytes to write 218 * @qiov: the buffers containing data to write 219 * @flags: zero or more bits allowed by 'supported_write_flags' 220 * 221 * @offset and @bytes will be a multiple of 'request_alignment', 222 * but the length of individual @qiov elements does not have to 223 * be a multiple. 224 * 225 * @bytes will always equal the total size of @qiov, and will be 226 * no larger than 'max_transfer'. 227 * 228 * The buffer in @qiov may point directly to guest memory. 229 */ 230 int coroutine_fn (*bdrv_co_pwritev)(BlockDriverState *bs, 231 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags); 232 233 /* 234 * Efficiently zero a region of the disk image. Typically an image format 235 * would use a compact metadata representation to implement this. This 236 * function pointer may be NULL or return -ENOSUP and .bdrv_co_writev() 237 * will be called instead. 238 */ 239 int coroutine_fn (*bdrv_co_pwrite_zeroes)(BlockDriverState *bs, 240 int64_t offset, int bytes, BdrvRequestFlags flags); 241 int coroutine_fn (*bdrv_co_pdiscard)(BlockDriverState *bs, 242 int64_t offset, int bytes); 243 244 /* Map [offset, offset + nbytes) range onto a child of @bs to copy from, 245 * and invoke bdrv_co_copy_range_from(child, ...), or invoke 246 * bdrv_co_copy_range_to() if @bs is the leaf child to copy data from. 247 * 248 * See the comment of bdrv_co_copy_range for the parameter and return value 249 * semantics. 250 */ 251 int coroutine_fn (*bdrv_co_copy_range_from)(BlockDriverState *bs, 252 BdrvChild *src, 253 uint64_t offset, 254 BdrvChild *dst, 255 uint64_t dst_offset, 256 uint64_t bytes, 257 BdrvRequestFlags read_flags, 258 BdrvRequestFlags write_flags); 259 260 /* Map [offset, offset + nbytes) range onto a child of bs to copy data to, 261 * and invoke bdrv_co_copy_range_to(child, src, ...), or perform the copy 262 * operation if @bs is the leaf and @src has the same BlockDriver. Return 263 * -ENOTSUP if @bs is the leaf but @src has a different BlockDriver. 264 * 265 * See the comment of bdrv_co_copy_range for the parameter and return value 266 * semantics. 267 */ 268 int coroutine_fn (*bdrv_co_copy_range_to)(BlockDriverState *bs, 269 BdrvChild *src, 270 uint64_t src_offset, 271 BdrvChild *dst, 272 uint64_t dst_offset, 273 uint64_t bytes, 274 BdrvRequestFlags read_flags, 275 BdrvRequestFlags write_flags); 276 277 /* 278 * Building block for bdrv_block_status[_above] and 279 * bdrv_is_allocated[_above]. The driver should answer only 280 * according to the current layer, and should only need to set 281 * BDRV_BLOCK_DATA, BDRV_BLOCK_ZERO, BDRV_BLOCK_OFFSET_VALID, 282 * and/or BDRV_BLOCK_RAW; if the current layer defers to a backing 283 * layer, the result should be 0 (and not BDRV_BLOCK_ZERO). See 284 * block.h for the overall meaning of the bits. As a hint, the 285 * flag want_zero is true if the caller cares more about precise 286 * mappings (favor accurate _OFFSET_VALID/_ZERO) or false for 287 * overall allocation (favor larger *pnum, perhaps by reporting 288 * _DATA instead of _ZERO). The block layer guarantees input 289 * clamped to bdrv_getlength() and aligned to request_alignment, 290 * as well as non-NULL pnum, map, and file; in turn, the driver 291 * must return an error or set pnum to an aligned non-zero value. 292 */ 293 int coroutine_fn (*bdrv_co_block_status)(BlockDriverState *bs, 294 bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum, 295 int64_t *map, BlockDriverState **file); 296 297 /* 298 * Invalidate any cached meta-data. 299 */ 300 void coroutine_fn (*bdrv_co_invalidate_cache)(BlockDriverState *bs, 301 Error **errp); 302 int (*bdrv_inactivate)(BlockDriverState *bs); 303 304 /* 305 * Flushes all data for all layers by calling bdrv_co_flush for underlying 306 * layers, if needed. This function is needed for deterministic 307 * synchronization of the flush finishing callback. 308 */ 309 int coroutine_fn (*bdrv_co_flush)(BlockDriverState *bs); 310 311 /* 312 * Flushes all data that was already written to the OS all the way down to 313 * the disk (for example file-posix.c calls fsync()). 314 */ 315 int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs); 316 317 /* 318 * Flushes all internal caches to the OS. The data may still sit in a 319 * writeback cache of the host OS, but it will survive a crash of the qemu 320 * process. 321 */ 322 int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs); 323 324 /* 325 * Drivers setting this field must be able to work with just a plain 326 * filename with '<protocol_name>:' as a prefix, and no other options. 327 * Options may be extracted from the filename by implementing 328 * bdrv_parse_filename. 329 */ 330 const char *protocol_name; 331 int coroutine_fn (*bdrv_co_truncate)(BlockDriverState *bs, int64_t offset, 332 PreallocMode prealloc, Error **errp); 333 334 int64_t (*bdrv_getlength)(BlockDriverState *bs); 335 bool has_variable_length; 336 int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs); 337 BlockMeasureInfo *(*bdrv_measure)(QemuOpts *opts, BlockDriverState *in_bs, 338 Error **errp); 339 340 int coroutine_fn (*bdrv_co_pwritev_compressed)(BlockDriverState *bs, 341 uint64_t offset, uint64_t bytes, QEMUIOVector *qiov); 342 343 int (*bdrv_snapshot_create)(BlockDriverState *bs, 344 QEMUSnapshotInfo *sn_info); 345 int (*bdrv_snapshot_goto)(BlockDriverState *bs, 346 const char *snapshot_id); 347 int (*bdrv_snapshot_delete)(BlockDriverState *bs, 348 const char *snapshot_id, 349 const char *name, 350 Error **errp); 351 int (*bdrv_snapshot_list)(BlockDriverState *bs, 352 QEMUSnapshotInfo **psn_info); 353 int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, 354 const char *snapshot_id, 355 const char *name, 356 Error **errp); 357 int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi); 358 ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs, 359 Error **errp); 360 361 int coroutine_fn (*bdrv_save_vmstate)(BlockDriverState *bs, 362 QEMUIOVector *qiov, 363 int64_t pos); 364 int coroutine_fn (*bdrv_load_vmstate)(BlockDriverState *bs, 365 QEMUIOVector *qiov, 366 int64_t pos); 367 368 int (*bdrv_change_backing_file)(BlockDriverState *bs, 369 const char *backing_file, const char *backing_fmt); 370 371 /* removable device specific */ 372 bool (*bdrv_is_inserted)(BlockDriverState *bs); 373 void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag); 374 void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked); 375 376 /* to control generic scsi devices */ 377 BlockAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs, 378 unsigned long int req, void *buf, 379 BlockCompletionFunc *cb, void *opaque); 380 int coroutine_fn (*bdrv_co_ioctl)(BlockDriverState *bs, 381 unsigned long int req, void *buf); 382 383 /* List of options for creating images, terminated by name == NULL */ 384 QemuOptsList *create_opts; 385 /* 386 * If this driver supports reopening images this contains a 387 * NULL-terminated list of the runtime options that can be 388 * modified. If an option in this list is unspecified during 389 * reopen then it _must_ be reset to its default value or return 390 * an error. 391 */ 392 const char *const *mutable_opts; 393 394 /* 395 * Returns 0 for completed check, -errno for internal errors. 396 * The check results are stored in result. 397 */ 398 int coroutine_fn (*bdrv_co_check)(BlockDriverState *bs, 399 BdrvCheckResult *result, 400 BdrvCheckMode fix); 401 402 int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts, 403 BlockDriverAmendStatusCB *status_cb, 404 void *cb_opaque, 405 Error **errp); 406 407 void (*bdrv_debug_event)(BlockDriverState *bs, BlkdebugEvent event); 408 409 /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */ 410 int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event, 411 const char *tag); 412 int (*bdrv_debug_remove_breakpoint)(BlockDriverState *bs, 413 const char *tag); 414 int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag); 415 bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag); 416 417 void (*bdrv_refresh_limits)(BlockDriverState *bs, Error **errp); 418 419 /* 420 * Returns 1 if newly created images are guaranteed to contain only 421 * zeros, 0 otherwise. 422 * Must return 0 if .bdrv_has_zero_init_truncate() returns 0. 423 */ 424 int (*bdrv_has_zero_init)(BlockDriverState *bs); 425 426 /* 427 * Returns 1 if new areas added by growing the image with 428 * PREALLOC_MODE_OFF contain only zeros, 0 otherwise. 429 */ 430 int (*bdrv_has_zero_init_truncate)(BlockDriverState *bs); 431 432 /* Remove fd handlers, timers, and other event loop callbacks so the event 433 * loop is no longer in use. Called with no in-flight requests and in 434 * depth-first traversal order with parents before child nodes. 435 */ 436 void (*bdrv_detach_aio_context)(BlockDriverState *bs); 437 438 /* Add fd handlers, timers, and other event loop callbacks so I/O requests 439 * can be processed again. Called with no in-flight requests and in 440 * depth-first traversal order with child nodes before parent nodes. 441 */ 442 void (*bdrv_attach_aio_context)(BlockDriverState *bs, 443 AioContext *new_context); 444 445 /* io queue for linux-aio */ 446 void (*bdrv_io_plug)(BlockDriverState *bs); 447 void (*bdrv_io_unplug)(BlockDriverState *bs); 448 449 /** 450 * Try to get @bs's logical and physical block size. 451 * On success, store them in @bsz and return zero. 452 * On failure, return negative errno. 453 */ 454 int (*bdrv_probe_blocksizes)(BlockDriverState *bs, BlockSizes *bsz); 455 /** 456 * Try to get @bs's geometry (cyls, heads, sectors) 457 * On success, store them in @geo and return 0. 458 * On failure return -errno. 459 * Only drivers that want to override guest geometry implement this 460 * callback; see hd_geometry_guess(). 461 */ 462 int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo); 463 464 /** 465 * bdrv_co_drain_begin is called if implemented in the beginning of a 466 * drain operation to drain and stop any internal sources of requests in 467 * the driver. 468 * bdrv_co_drain_end is called if implemented at the end of the drain. 469 * 470 * They should be used by the driver to e.g. manage scheduled I/O 471 * requests, or toggle an internal state. After the end of the drain new 472 * requests will continue normally. 473 */ 474 void coroutine_fn (*bdrv_co_drain_begin)(BlockDriverState *bs); 475 void coroutine_fn (*bdrv_co_drain_end)(BlockDriverState *bs); 476 477 void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child, 478 Error **errp); 479 void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child, 480 Error **errp); 481 482 /** 483 * Informs the block driver that a permission change is intended. The 484 * driver checks whether the change is permissible and may take other 485 * preparations for the change (e.g. get file system locks). This operation 486 * is always followed either by a call to either .bdrv_set_perm or 487 * .bdrv_abort_perm_update. 488 * 489 * Checks whether the requested set of cumulative permissions in @perm 490 * can be granted for accessing @bs and whether no other users are using 491 * permissions other than those given in @shared (both arguments take 492 * BLK_PERM_* bitmasks). 493 * 494 * If both conditions are met, 0 is returned. Otherwise, -errno is returned 495 * and errp is set to an error describing the conflict. 496 */ 497 int (*bdrv_check_perm)(BlockDriverState *bs, uint64_t perm, 498 uint64_t shared, Error **errp); 499 500 /** 501 * Called to inform the driver that the set of cumulative set of used 502 * permissions for @bs has changed to @perm, and the set of sharable 503 * permission to @shared. The driver can use this to propagate changes to 504 * its children (i.e. request permissions only if a parent actually needs 505 * them). 506 * 507 * This function is only invoked after bdrv_check_perm(), so block drivers 508 * may rely on preparations made in their .bdrv_check_perm implementation. 509 */ 510 void (*bdrv_set_perm)(BlockDriverState *bs, uint64_t perm, uint64_t shared); 511 512 /* 513 * Called to inform the driver that after a previous bdrv_check_perm() 514 * call, the permission update is not performed and any preparations made 515 * for it (e.g. taken file locks) need to be undone. 516 * 517 * This function can be called even for nodes that never saw a 518 * bdrv_check_perm() call. It is a no-op then. 519 */ 520 void (*bdrv_abort_perm_update)(BlockDriverState *bs); 521 522 /** 523 * Returns in @nperm and @nshared the permissions that the driver for @bs 524 * needs on its child @c, based on the cumulative permissions requested by 525 * the parents in @parent_perm and @parent_shared. 526 * 527 * If @c is NULL, return the permissions for attaching a new child for the 528 * given @role. 529 * 530 * If @reopen_queue is non-NULL, don't return the currently needed 531 * permissions, but those that will be needed after applying the 532 * @reopen_queue. 533 */ 534 void (*bdrv_child_perm)(BlockDriverState *bs, BdrvChild *c, 535 const BdrvChildRole *role, 536 BlockReopenQueue *reopen_queue, 537 uint64_t parent_perm, uint64_t parent_shared, 538 uint64_t *nperm, uint64_t *nshared); 539 540 /** 541 * Bitmaps should be marked as 'IN_USE' in the image on reopening image 542 * as rw. This handler should realize it. It also should unset readonly 543 * field of BlockDirtyBitmap's in case of success. 544 */ 545 int (*bdrv_reopen_bitmaps_rw)(BlockDriverState *bs, Error **errp); 546 bool (*bdrv_can_store_new_dirty_bitmap)(BlockDriverState *bs, 547 const char *name, 548 uint32_t granularity, 549 Error **errp); 550 void (*bdrv_remove_persistent_dirty_bitmap)(BlockDriverState *bs, 551 const char *name, 552 Error **errp); 553 554 /** 555 * Register/unregister a buffer for I/O. For example, when the driver is 556 * interested to know the memory areas that will later be used in iovs, so 557 * that it can do IOMMU mapping with VFIO etc., in order to get better 558 * performance. In the case of VFIO drivers, this callback is used to do 559 * DMA mapping for hot buffers. 560 */ 561 void (*bdrv_register_buf)(BlockDriverState *bs, void *host, size_t size); 562 void (*bdrv_unregister_buf)(BlockDriverState *bs, void *host); 563 QLIST_ENTRY(BlockDriver) list; 564 565 /* Pointer to a NULL-terminated array of names of strong options 566 * that can be specified for bdrv_open(). A strong option is one 567 * that changes the data of a BDS. 568 * If this pointer is NULL, the array is considered empty. 569 * "filename" and "driver" are always considered strong. */ 570 const char *const *strong_runtime_opts; 571 }; 572 573 typedef struct BlockLimits { 574 /* Alignment requirement, in bytes, for offset/length of I/O 575 * requests. Must be a power of 2 less than INT_MAX; defaults to 576 * 1 for drivers with modern byte interfaces, and to 512 577 * otherwise. */ 578 uint32_t request_alignment; 579 580 /* Maximum number of bytes that can be discarded at once (since it 581 * is signed, it must be < 2G, if set). Must be multiple of 582 * pdiscard_alignment, but need not be power of 2. May be 0 if no 583 * inherent 32-bit limit */ 584 int32_t max_pdiscard; 585 586 /* Optimal alignment for discard requests in bytes. A power of 2 587 * is best but not mandatory. Must be a multiple of 588 * bl.request_alignment, and must be less than max_pdiscard if 589 * that is set. May be 0 if bl.request_alignment is good enough */ 590 uint32_t pdiscard_alignment; 591 592 /* Maximum number of bytes that can zeroized at once (since it is 593 * signed, it must be < 2G, if set). Must be multiple of 594 * pwrite_zeroes_alignment. May be 0 if no inherent 32-bit limit */ 595 int32_t max_pwrite_zeroes; 596 597 /* Optimal alignment for write zeroes requests in bytes. A power 598 * of 2 is best but not mandatory. Must be a multiple of 599 * bl.request_alignment, and must be less than max_pwrite_zeroes 600 * if that is set. May be 0 if bl.request_alignment is good 601 * enough */ 602 uint32_t pwrite_zeroes_alignment; 603 604 /* Optimal transfer length in bytes. A power of 2 is best but not 605 * mandatory. Must be a multiple of bl.request_alignment, or 0 if 606 * no preferred size */ 607 uint32_t opt_transfer; 608 609 /* Maximal transfer length in bytes. Need not be power of 2, but 610 * must be multiple of opt_transfer and bl.request_alignment, or 0 611 * for no 32-bit limit. For now, anything larger than INT_MAX is 612 * clamped down. */ 613 uint32_t max_transfer; 614 615 /* memory alignment, in bytes so that no bounce buffer is needed */ 616 size_t min_mem_alignment; 617 618 /* memory alignment, in bytes, for bounce buffer */ 619 size_t opt_mem_alignment; 620 621 /* maximum number of iovec elements */ 622 int max_iov; 623 } BlockLimits; 624 625 typedef struct BdrvOpBlocker BdrvOpBlocker; 626 627 typedef struct BdrvAioNotifier { 628 void (*attached_aio_context)(AioContext *new_context, void *opaque); 629 void (*detach_aio_context)(void *opaque); 630 631 void *opaque; 632 bool deleted; 633 634 QLIST_ENTRY(BdrvAioNotifier) list; 635 } BdrvAioNotifier; 636 637 struct BdrvChildRole { 638 /* If true, bdrv_replace_node() doesn't change the node this BdrvChild 639 * points to. */ 640 bool stay_at_node; 641 642 /* If true, the parent is a BlockDriverState and bdrv_next_all_states() 643 * will return it. This information is used for drain_all, where every node 644 * will be drained separately, so the drain only needs to be propagated to 645 * non-BDS parents. */ 646 bool parent_is_bds; 647 648 void (*inherit_options)(int *child_flags, QDict *child_options, 649 int parent_flags, QDict *parent_options); 650 651 void (*change_media)(BdrvChild *child, bool load); 652 void (*resize)(BdrvChild *child); 653 654 /* Returns a name that is supposedly more useful for human users than the 655 * node name for identifying the node in question (in particular, a BB 656 * name), or NULL if the parent can't provide a better name. */ 657 const char *(*get_name)(BdrvChild *child); 658 659 /* Returns a malloced string that describes the parent of the child for a 660 * human reader. This could be a node-name, BlockBackend name, qdev ID or 661 * QOM path of the device owning the BlockBackend, job type and ID etc. The 662 * caller is responsible for freeing the memory. */ 663 char *(*get_parent_desc)(BdrvChild *child); 664 665 /* 666 * If this pair of functions is implemented, the parent doesn't issue new 667 * requests after returning from .drained_begin() until .drained_end() is 668 * called. 669 * 670 * These functions must not change the graph (and therefore also must not 671 * call aio_poll(), which could change the graph indirectly). 672 * 673 * If drained_end() schedules background operations, it must atomically 674 * increment *drained_end_counter for each such operation and atomically 675 * decrement it once the operation has settled. 676 * 677 * Note that this can be nested. If drained_begin() was called twice, new 678 * I/O is allowed only after drained_end() was called twice, too. 679 */ 680 void (*drained_begin)(BdrvChild *child); 681 void (*drained_end)(BdrvChild *child, int *drained_end_counter); 682 683 /* 684 * Returns whether the parent has pending requests for the child. This 685 * callback is polled after .drained_begin() has been called until all 686 * activity on the child has stopped. 687 */ 688 bool (*drained_poll)(BdrvChild *child); 689 690 /* Notifies the parent that the child has been activated/inactivated (e.g. 691 * when migration is completing) and it can start/stop requesting 692 * permissions and doing I/O on it. */ 693 void (*activate)(BdrvChild *child, Error **errp); 694 int (*inactivate)(BdrvChild *child); 695 696 void (*attach)(BdrvChild *child); 697 void (*detach)(BdrvChild *child); 698 699 /* Notifies the parent that the filename of its child has changed (e.g. 700 * because the direct child was removed from the backing chain), so that it 701 * can update its reference. */ 702 int (*update_filename)(BdrvChild *child, BlockDriverState *new_base, 703 const char *filename, Error **errp); 704 705 bool (*can_set_aio_ctx)(BdrvChild *child, AioContext *ctx, 706 GSList **ignore, Error **errp); 707 void (*set_aio_ctx)(BdrvChild *child, AioContext *ctx, GSList **ignore); 708 }; 709 710 extern const BdrvChildRole child_file; 711 extern const BdrvChildRole child_format; 712 extern const BdrvChildRole child_backing; 713 714 struct BdrvChild { 715 BlockDriverState *bs; 716 char *name; 717 const BdrvChildRole *role; 718 void *opaque; 719 720 /** 721 * Granted permissions for operating on this BdrvChild (BLK_PERM_* bitmask) 722 */ 723 uint64_t perm; 724 725 /** 726 * Permissions that can still be granted to other users of @bs while this 727 * BdrvChild is still attached to it. (BLK_PERM_* bitmask) 728 */ 729 uint64_t shared_perm; 730 731 /* backup of permissions during permission update procedure */ 732 bool has_backup_perm; 733 uint64_t backup_perm; 734 uint64_t backup_shared_perm; 735 736 /* 737 * This link is frozen: the child can neither be replaced nor 738 * detached from the parent. 739 */ 740 bool frozen; 741 742 /* 743 * How many times the parent of this child has been drained 744 * (through role->drained_*). 745 * Usually, this is equal to bs->quiesce_counter (potentially 746 * reduced by bdrv_drain_all_count). It may differ while the 747 * child is entering or leaving a drained section. 748 */ 749 int parent_quiesce_counter; 750 751 QLIST_ENTRY(BdrvChild) next; 752 QLIST_ENTRY(BdrvChild) next_parent; 753 }; 754 755 /* 756 * Note: the function bdrv_append() copies and swaps contents of 757 * BlockDriverStates, so if you add new fields to this struct, please 758 * inspect bdrv_append() to determine if the new fields need to be 759 * copied as well. 760 */ 761 struct BlockDriverState { 762 /* Protected by big QEMU lock or read-only after opening. No special 763 * locking needed during I/O... 764 */ 765 int open_flags; /* flags used to open the file, re-used for re-open */ 766 bool read_only; /* if true, the media is read only */ 767 bool encrypted; /* if true, the media is encrypted */ 768 bool sg; /* if true, the device is a /dev/sg* */ 769 bool probed; /* if true, format was probed rather than specified */ 770 bool force_share; /* if true, always allow all shared permissions */ 771 bool implicit; /* if true, this filter node was automatically inserted */ 772 773 BlockDriver *drv; /* NULL means no media */ 774 void *opaque; 775 776 AioContext *aio_context; /* event loop used for fd handlers, timers, etc */ 777 /* long-running tasks intended to always use the same AioContext as this 778 * BDS may register themselves in this list to be notified of changes 779 * regarding this BDS's context */ 780 QLIST_HEAD(, BdrvAioNotifier) aio_notifiers; 781 bool walking_aio_notifiers; /* to make removal during iteration safe */ 782 783 char filename[PATH_MAX]; 784 char backing_file[PATH_MAX]; /* if non zero, the image is a diff of 785 this file image */ 786 /* The backing filename indicated by the image header; if we ever 787 * open this file, then this is replaced by the resulting BDS's 788 * filename (i.e. after a bdrv_refresh_filename() run). */ 789 char auto_backing_file[PATH_MAX]; 790 char backing_format[16]; /* if non-zero and backing_file exists */ 791 792 QDict *full_open_options; 793 char exact_filename[PATH_MAX]; 794 795 BdrvChild *backing; 796 BdrvChild *file; 797 798 /* I/O Limits */ 799 BlockLimits bl; 800 801 /* Flags honored during pwrite (so far: BDRV_REQ_FUA, 802 * BDRV_REQ_WRITE_UNCHANGED). 803 * If a driver does not support BDRV_REQ_WRITE_UNCHANGED, those 804 * writes will be issued as normal writes without the flag set. 805 * This is important to note for drivers that do not explicitly 806 * request a WRITE permission for their children and instead take 807 * the same permissions as their parent did (this is commonly what 808 * block filters do). Such drivers have to be aware that the 809 * parent may have taken a WRITE_UNCHANGED permission only and is 810 * issuing such requests. Drivers either must make sure that 811 * these requests do not result in plain WRITE accesses (usually 812 * by supporting BDRV_REQ_WRITE_UNCHANGED, and then forwarding 813 * every incoming write request as-is, including potentially that 814 * flag), or they have to explicitly take the WRITE permission for 815 * their children. */ 816 unsigned int supported_write_flags; 817 /* Flags honored during pwrite_zeroes (so far: BDRV_REQ_FUA, 818 * BDRV_REQ_MAY_UNMAP, BDRV_REQ_WRITE_UNCHANGED) */ 819 unsigned int supported_zero_flags; 820 821 /* the following member gives a name to every node on the bs graph. */ 822 char node_name[32]; 823 /* element of the list of named nodes building the graph */ 824 QTAILQ_ENTRY(BlockDriverState) node_list; 825 /* element of the list of all BlockDriverStates (all_bdrv_states) */ 826 QTAILQ_ENTRY(BlockDriverState) bs_list; 827 /* element of the list of monitor-owned BDS */ 828 QTAILQ_ENTRY(BlockDriverState) monitor_list; 829 int refcnt; 830 831 /* operation blockers */ 832 QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX]; 833 834 /* The node that this node inherited default options from (and a reopen on 835 * which can affect this node by changing these defaults). This is always a 836 * parent node of this node. */ 837 BlockDriverState *inherits_from; 838 QLIST_HEAD(, BdrvChild) children; 839 QLIST_HEAD(, BdrvChild) parents; 840 841 QDict *options; 842 QDict *explicit_options; 843 BlockdevDetectZeroesOptions detect_zeroes; 844 845 /* The error object in use for blocking operations on backing_hd */ 846 Error *backing_blocker; 847 848 /* Protected by AioContext lock */ 849 850 /* If we are reading a disk image, give its size in sectors. 851 * Generally read-only; it is written to by load_snapshot and 852 * save_snaphost, but the block layer is quiescent during those. 853 */ 854 int64_t total_sectors; 855 856 /* Callback before write request is processed */ 857 NotifierWithReturnList before_write_notifiers; 858 859 /* threshold limit for writes, in bytes. "High water mark". */ 860 uint64_t write_threshold_offset; 861 NotifierWithReturn write_threshold_notifier; 862 863 /* Writing to the list requires the BQL _and_ the dirty_bitmap_mutex. 864 * Reading from the list can be done with either the BQL or the 865 * dirty_bitmap_mutex. Modifying a bitmap only requires 866 * dirty_bitmap_mutex. */ 867 QemuMutex dirty_bitmap_mutex; 868 QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps; 869 870 /* Offset after the highest byte written to */ 871 Stat64 wr_highest_offset; 872 873 /* If true, copy read backing sectors into image. Can be >1 if more 874 * than one client has requested copy-on-read. Accessed with atomic 875 * ops. 876 */ 877 int copy_on_read; 878 879 /* number of in-flight requests; overall and serialising. 880 * Accessed with atomic ops. 881 */ 882 unsigned int in_flight; 883 unsigned int serialising_in_flight; 884 885 /* counter for nested bdrv_io_plug. 886 * Accessed with atomic ops. 887 */ 888 unsigned io_plugged; 889 890 /* do we need to tell the quest if we have a volatile write cache? */ 891 int enable_write_cache; 892 893 /* Accessed with atomic ops. */ 894 int quiesce_counter; 895 int recursive_quiesce_counter; 896 897 unsigned int write_gen; /* Current data generation */ 898 899 /* Protected by reqs_lock. */ 900 CoMutex reqs_lock; 901 QLIST_HEAD(, BdrvTrackedRequest) tracked_requests; 902 CoQueue flush_queue; /* Serializing flush queue */ 903 bool active_flush_req; /* Flush request in flight? */ 904 905 /* Only read/written by whoever has set active_flush_req to true. */ 906 unsigned int flushed_gen; /* Flushed write generation */ 907 908 /* BdrvChild links to this node may never be frozen */ 909 bool never_freeze; 910 }; 911 912 struct BlockBackendRootState { 913 int open_flags; 914 bool read_only; 915 BlockdevDetectZeroesOptions detect_zeroes; 916 }; 917 918 typedef enum BlockMirrorBackingMode { 919 /* Reuse the existing backing chain from the source for the target. 920 * - sync=full: Set backing BDS to NULL. 921 * - sync=top: Use source's backing BDS. 922 * - sync=none: Use source as the backing BDS. */ 923 MIRROR_SOURCE_BACKING_CHAIN, 924 925 /* Open the target's backing chain completely anew */ 926 MIRROR_OPEN_BACKING_CHAIN, 927 928 /* Do not change the target's backing BDS after job completion */ 929 MIRROR_LEAVE_BACKING_CHAIN, 930 } BlockMirrorBackingMode; 931 932 static inline BlockDriverState *backing_bs(BlockDriverState *bs) 933 { 934 return bs->backing ? bs->backing->bs : NULL; 935 } 936 937 938 /* Essential block drivers which must always be statically linked into qemu, and 939 * which therefore can be accessed without using bdrv_find_format() */ 940 extern BlockDriver bdrv_file; 941 extern BlockDriver bdrv_raw; 942 extern BlockDriver bdrv_qcow2; 943 944 int coroutine_fn bdrv_co_preadv(BdrvChild *child, 945 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 946 BdrvRequestFlags flags); 947 int coroutine_fn bdrv_co_pwritev(BdrvChild *child, 948 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 949 BdrvRequestFlags flags); 950 951 static inline int coroutine_fn bdrv_co_pread(BdrvChild *child, 952 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags) 953 { 954 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); 955 956 return bdrv_co_preadv(child, offset, bytes, &qiov, flags); 957 } 958 959 static inline int coroutine_fn bdrv_co_pwrite(BdrvChild *child, 960 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags) 961 { 962 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); 963 964 return bdrv_co_pwritev(child, offset, bytes, &qiov, flags); 965 } 966 967 extern unsigned int bdrv_drain_all_count; 968 void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent); 969 void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent); 970 971 int get_tmp_filename(char *filename, int size); 972 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, 973 const char *filename); 974 975 void bdrv_parse_filename_strip_prefix(const char *filename, const char *prefix, 976 QDict *options); 977 978 979 /** 980 * bdrv_add_before_write_notifier: 981 * 982 * Register a callback that is invoked before write requests are processed but 983 * after any throttling or waiting for overlapping requests. 984 */ 985 void bdrv_add_before_write_notifier(BlockDriverState *bs, 986 NotifierWithReturn *notifier); 987 988 /** 989 * bdrv_add_aio_context_notifier: 990 * 991 * If a long-running job intends to be always run in the same AioContext as a 992 * certain BDS, it may use this function to be notified of changes regarding the 993 * association of the BDS to an AioContext. 994 * 995 * attached_aio_context() is called after the target BDS has been attached to a 996 * new AioContext; detach_aio_context() is called before the target BDS is being 997 * detached from its old AioContext. 998 */ 999 void bdrv_add_aio_context_notifier(BlockDriverState *bs, 1000 void (*attached_aio_context)(AioContext *new_context, void *opaque), 1001 void (*detach_aio_context)(void *opaque), void *opaque); 1002 1003 /** 1004 * bdrv_remove_aio_context_notifier: 1005 * 1006 * Unsubscribe of change notifications regarding the BDS's AioContext. The 1007 * parameters given here have to be the same as those given to 1008 * bdrv_add_aio_context_notifier(). 1009 */ 1010 void bdrv_remove_aio_context_notifier(BlockDriverState *bs, 1011 void (*aio_context_attached)(AioContext *, 1012 void *), 1013 void (*aio_context_detached)(void *), 1014 void *opaque); 1015 1016 /** 1017 * bdrv_wakeup: 1018 * @bs: The BlockDriverState for which an I/O operation has been completed. 1019 * 1020 * Wake up the main thread if it is waiting on BDRV_POLL_WHILE. During 1021 * synchronous I/O on a BlockDriverState that is attached to another 1022 * I/O thread, the main thread lets the I/O thread's event loop run, 1023 * waiting for the I/O operation to complete. A bdrv_wakeup will wake 1024 * up the main thread if necessary. 1025 * 1026 * Manual calls to bdrv_wakeup are rarely necessary, because 1027 * bdrv_dec_in_flight already calls it. 1028 */ 1029 void bdrv_wakeup(BlockDriverState *bs); 1030 1031 #ifdef _WIN32 1032 int is_windows_drive(const char *filename); 1033 #endif 1034 1035 /** 1036 * stream_start: 1037 * @job_id: The id of the newly-created job, or %NULL to use the 1038 * device name of @bs. 1039 * @bs: Block device to operate on. 1040 * @base: Block device that will become the new base, or %NULL to 1041 * flatten the whole backing file chain onto @bs. 1042 * @backing_file_str: The file name that will be written to @bs as the 1043 * the new backing file if the job completes. Ignored if @base is %NULL. 1044 * @creation_flags: Flags that control the behavior of the Job lifetime. 1045 * See @BlockJobCreateFlags 1046 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1047 * @on_error: The action to take upon error. 1048 * @errp: Error object. 1049 * 1050 * Start a streaming operation on @bs. Clusters that are unallocated 1051 * in @bs, but allocated in any image between @base and @bs (both 1052 * exclusive) will be written to @bs. At the end of a successful 1053 * streaming job, the backing file of @bs will be changed to 1054 * @backing_file_str in the written image and to @base in the live 1055 * BlockDriverState. 1056 */ 1057 void stream_start(const char *job_id, BlockDriverState *bs, 1058 BlockDriverState *base, const char *backing_file_str, 1059 int creation_flags, int64_t speed, 1060 BlockdevOnError on_error, Error **errp); 1061 1062 /** 1063 * commit_start: 1064 * @job_id: The id of the newly-created job, or %NULL to use the 1065 * device name of @bs. 1066 * @bs: Active block device. 1067 * @top: Top 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 * @backing_file_str: String to use as the backing file in @top's overlay 1074 * @filter_node_name: The node name that should be assigned to the filter 1075 * driver that the commit job inserts into the graph above @top. NULL means 1076 * that a node name should be autogenerated. 1077 * @errp: Error object. 1078 * 1079 */ 1080 void commit_start(const char *job_id, BlockDriverState *bs, 1081 BlockDriverState *base, BlockDriverState *top, 1082 int creation_flags, int64_t speed, 1083 BlockdevOnError on_error, const char *backing_file_str, 1084 const char *filter_node_name, Error **errp); 1085 /** 1086 * commit_active_start: 1087 * @job_id: The id of the newly-created job, or %NULL to use the 1088 * device name of @bs. 1089 * @bs: Active block device to be committed. 1090 * @base: Block device that will be written into, and become the new top. 1091 * @creation_flags: Flags that control the behavior of the Job lifetime. 1092 * See @BlockJobCreateFlags 1093 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1094 * @on_error: The action to take upon error. 1095 * @filter_node_name: The node name that should be assigned to the filter 1096 * driver that the commit job inserts into the graph above @bs. NULL means that 1097 * a node name should be autogenerated. 1098 * @cb: Completion function for the job. 1099 * @opaque: Opaque pointer value passed to @cb. 1100 * @auto_complete: Auto complete the job. 1101 * @errp: Error object. 1102 * 1103 */ 1104 BlockJob *commit_active_start(const char *job_id, BlockDriverState *bs, 1105 BlockDriverState *base, int creation_flags, 1106 int64_t speed, BlockdevOnError on_error, 1107 const char *filter_node_name, 1108 BlockCompletionFunc *cb, void *opaque, 1109 bool auto_complete, Error **errp); 1110 /* 1111 * mirror_start: 1112 * @job_id: The id of the newly-created job, or %NULL to use the 1113 * device name of @bs. 1114 * @bs: Block device to operate on. 1115 * @target: Block device to write to. 1116 * @replaces: Block graph node name to replace once the mirror is done. Can 1117 * only be used when full mirroring is selected. 1118 * @creation_flags: Flags that control the behavior of the Job lifetime. 1119 * See @BlockJobCreateFlags 1120 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1121 * @granularity: The chosen granularity for the dirty bitmap. 1122 * @buf_size: The amount of data that can be in flight at one time. 1123 * @mode: Whether to collapse all images in the chain to the target. 1124 * @backing_mode: How to establish the target's backing chain after completion. 1125 * @zero_target: Whether the target should be explicitly zero-initialized 1126 * @on_source_error: The action to take upon error reading from the source. 1127 * @on_target_error: The action to take upon error writing to the target. 1128 * @unmap: Whether to unmap target where source sectors only contain zeroes. 1129 * @filter_node_name: The node name that should be assigned to the filter 1130 * driver that the mirror job inserts into the graph above @bs. NULL means that 1131 * a node name should be autogenerated. 1132 * @copy_mode: When to trigger writes to the target. 1133 * @errp: Error object. 1134 * 1135 * Start a mirroring operation on @bs. Clusters that are allocated 1136 * in @bs will be written to @target until the job is cancelled or 1137 * manually completed. At the end of a successful mirroring job, 1138 * @bs will be switched to read from @target. 1139 */ 1140 void mirror_start(const char *job_id, BlockDriverState *bs, 1141 BlockDriverState *target, const char *replaces, 1142 int creation_flags, int64_t speed, 1143 uint32_t granularity, int64_t buf_size, 1144 MirrorSyncMode mode, BlockMirrorBackingMode backing_mode, 1145 bool zero_target, 1146 BlockdevOnError on_source_error, 1147 BlockdevOnError on_target_error, 1148 bool unmap, const char *filter_node_name, 1149 MirrorCopyMode copy_mode, Error **errp); 1150 1151 /* 1152 * backup_job_create: 1153 * @job_id: The id of the newly-created job, or %NULL to use the 1154 * device name of @bs. 1155 * @bs: Block device to operate on. 1156 * @target: Block device to write to. 1157 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1158 * @sync_mode: What parts of the disk image should be copied to the destination. 1159 * @sync_bitmap: The dirty bitmap if sync_mode is 'bitmap' or 'incremental' 1160 * @bitmap_mode: The bitmap synchronization policy to use. 1161 * @on_source_error: The action to take upon error reading from the source. 1162 * @on_target_error: The action to take upon error writing to the target. 1163 * @creation_flags: Flags that control the behavior of the Job lifetime. 1164 * See @BlockJobCreateFlags 1165 * @cb: Completion function for the job. 1166 * @opaque: Opaque pointer value passed to @cb. 1167 * @txn: Transaction that this job is part of (may be NULL). 1168 * 1169 * Create a backup operation on @bs. Clusters in @bs are written to @target 1170 * until the job is cancelled or manually completed. 1171 */ 1172 BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, 1173 BlockDriverState *target, int64_t speed, 1174 MirrorSyncMode sync_mode, 1175 BdrvDirtyBitmap *sync_bitmap, 1176 BitmapSyncMode bitmap_mode, 1177 bool compress, 1178 BlockdevOnError on_source_error, 1179 BlockdevOnError on_target_error, 1180 int creation_flags, 1181 BlockCompletionFunc *cb, void *opaque, 1182 JobTxn *txn, Error **errp); 1183 1184 void hmp_drive_add_node(Monitor *mon, const char *optstr); 1185 1186 BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, 1187 const char *child_name, 1188 const BdrvChildRole *child_role, 1189 AioContext *ctx, 1190 uint64_t perm, uint64_t shared_perm, 1191 void *opaque, Error **errp); 1192 void bdrv_root_unref_child(BdrvChild *child); 1193 1194 /** 1195 * Sets a BdrvChild's permissions. Avoid if the parent is a BDS; use 1196 * bdrv_child_refresh_perms() instead and make the parent's 1197 * .bdrv_child_perm() implementation return the correct values. 1198 */ 1199 int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, 1200 Error **errp); 1201 1202 /** 1203 * Calls bs->drv->bdrv_child_perm() and updates the child's permission 1204 * masks with the result. 1205 * Drivers should invoke this function whenever an event occurs that 1206 * makes their .bdrv_child_perm() implementation return different 1207 * values than before, but which will not result in the block layer 1208 * automatically refreshing the permissions. 1209 */ 1210 int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp); 1211 1212 /* Default implementation for BlockDriver.bdrv_child_perm() that can be used by 1213 * block filters: Forward CONSISTENT_READ, WRITE, WRITE_UNCHANGED and RESIZE to 1214 * all children */ 1215 void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, 1216 const BdrvChildRole *role, 1217 BlockReopenQueue *reopen_queue, 1218 uint64_t perm, uint64_t shared, 1219 uint64_t *nperm, uint64_t *nshared); 1220 1221 /* Default implementation for BlockDriver.bdrv_child_perm() that can be used by 1222 * (non-raw) image formats: Like above for bs->backing, but for bs->file it 1223 * requires WRITE | RESIZE for read-write images, always requires 1224 * CONSISTENT_READ and doesn't share WRITE. */ 1225 void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c, 1226 const BdrvChildRole *role, 1227 BlockReopenQueue *reopen_queue, 1228 uint64_t perm, uint64_t shared, 1229 uint64_t *nperm, uint64_t *nshared); 1230 1231 /* 1232 * Default implementation for drivers to pass bdrv_co_block_status() to 1233 * their file. 1234 */ 1235 int coroutine_fn bdrv_co_block_status_from_file(BlockDriverState *bs, 1236 bool want_zero, 1237 int64_t offset, 1238 int64_t bytes, 1239 int64_t *pnum, 1240 int64_t *map, 1241 BlockDriverState **file); 1242 /* 1243 * Default implementation for drivers to pass bdrv_co_block_status() to 1244 * their backing file. 1245 */ 1246 int coroutine_fn bdrv_co_block_status_from_backing(BlockDriverState *bs, 1247 bool want_zero, 1248 int64_t offset, 1249 int64_t bytes, 1250 int64_t *pnum, 1251 int64_t *map, 1252 BlockDriverState **file); 1253 const char *bdrv_get_parent_name(const BlockDriverState *bs); 1254 void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp); 1255 bool blk_dev_has_removable_media(BlockBackend *blk); 1256 bool blk_dev_has_tray(BlockBackend *blk); 1257 void blk_dev_eject_request(BlockBackend *blk, bool force); 1258 bool blk_dev_is_tray_open(BlockBackend *blk); 1259 bool blk_dev_is_medium_locked(BlockBackend *blk); 1260 1261 void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes); 1262 1263 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out); 1264 void bdrv_restore_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *backup); 1265 bool bdrv_dirty_bitmap_merge_internal(BdrvDirtyBitmap *dest, 1266 const BdrvDirtyBitmap *src, 1267 HBitmap **backup, bool lock); 1268 1269 void bdrv_inc_in_flight(BlockDriverState *bs); 1270 void bdrv_dec_in_flight(BlockDriverState *bs); 1271 1272 void blockdev_close_all_bdrv_states(void); 1273 1274 int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, uint64_t src_offset, 1275 BdrvChild *dst, uint64_t dst_offset, 1276 uint64_t bytes, 1277 BdrvRequestFlags read_flags, 1278 BdrvRequestFlags write_flags); 1279 int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, uint64_t src_offset, 1280 BdrvChild *dst, uint64_t dst_offset, 1281 uint64_t bytes, 1282 BdrvRequestFlags read_flags, 1283 BdrvRequestFlags write_flags); 1284 1285 int refresh_total_sectors(BlockDriverState *bs, int64_t hint); 1286 1287 #endif /* BLOCK_INT_H */ 1288