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 */ 423 int (*bdrv_has_zero_init)(BlockDriverState *bs); 424 425 /* Remove fd handlers, timers, and other event loop callbacks so the event 426 * loop is no longer in use. Called with no in-flight requests and in 427 * depth-first traversal order with parents before child nodes. 428 */ 429 void (*bdrv_detach_aio_context)(BlockDriverState *bs); 430 431 /* Add fd handlers, timers, and other event loop callbacks so I/O requests 432 * can be processed again. Called with no in-flight requests and in 433 * depth-first traversal order with child nodes before parent nodes. 434 */ 435 void (*bdrv_attach_aio_context)(BlockDriverState *bs, 436 AioContext *new_context); 437 438 /* io queue for linux-aio */ 439 void (*bdrv_io_plug)(BlockDriverState *bs); 440 void (*bdrv_io_unplug)(BlockDriverState *bs); 441 442 /** 443 * Try to get @bs's logical and physical block size. 444 * On success, store them in @bsz and return zero. 445 * On failure, return negative errno. 446 */ 447 int (*bdrv_probe_blocksizes)(BlockDriverState *bs, BlockSizes *bsz); 448 /** 449 * Try to get @bs's geometry (cyls, heads, sectors) 450 * On success, store them in @geo and return 0. 451 * On failure return -errno. 452 * Only drivers that want to override guest geometry implement this 453 * callback; see hd_geometry_guess(). 454 */ 455 int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo); 456 457 /** 458 * bdrv_co_drain_begin is called if implemented in the beginning of a 459 * drain operation to drain and stop any internal sources of requests in 460 * the driver. 461 * bdrv_co_drain_end is called if implemented at the end of the drain. 462 * 463 * They should be used by the driver to e.g. manage scheduled I/O 464 * requests, or toggle an internal state. After the end of the drain new 465 * requests will continue normally. 466 */ 467 void coroutine_fn (*bdrv_co_drain_begin)(BlockDriverState *bs); 468 void coroutine_fn (*bdrv_co_drain_end)(BlockDriverState *bs); 469 470 void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child, 471 Error **errp); 472 void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child, 473 Error **errp); 474 475 /** 476 * Informs the block driver that a permission change is intended. The 477 * driver checks whether the change is permissible and may take other 478 * preparations for the change (e.g. get file system locks). This operation 479 * is always followed either by a call to either .bdrv_set_perm or 480 * .bdrv_abort_perm_update. 481 * 482 * Checks whether the requested set of cumulative permissions in @perm 483 * can be granted for accessing @bs and whether no other users are using 484 * permissions other than those given in @shared (both arguments take 485 * BLK_PERM_* bitmasks). 486 * 487 * If both conditions are met, 0 is returned. Otherwise, -errno is returned 488 * and errp is set to an error describing the conflict. 489 */ 490 int (*bdrv_check_perm)(BlockDriverState *bs, uint64_t perm, 491 uint64_t shared, Error **errp); 492 493 /** 494 * Called to inform the driver that the set of cumulative set of used 495 * permissions for @bs has changed to @perm, and the set of sharable 496 * permission to @shared. The driver can use this to propagate changes to 497 * its children (i.e. request permissions only if a parent actually needs 498 * them). 499 * 500 * This function is only invoked after bdrv_check_perm(), so block drivers 501 * may rely on preparations made in their .bdrv_check_perm implementation. 502 */ 503 void (*bdrv_set_perm)(BlockDriverState *bs, uint64_t perm, uint64_t shared); 504 505 /* 506 * Called to inform the driver that after a previous bdrv_check_perm() 507 * call, the permission update is not performed and any preparations made 508 * for it (e.g. taken file locks) need to be undone. 509 * 510 * This function can be called even for nodes that never saw a 511 * bdrv_check_perm() call. It is a no-op then. 512 */ 513 void (*bdrv_abort_perm_update)(BlockDriverState *bs); 514 515 /** 516 * Returns in @nperm and @nshared the permissions that the driver for @bs 517 * needs on its child @c, based on the cumulative permissions requested by 518 * the parents in @parent_perm and @parent_shared. 519 * 520 * If @c is NULL, return the permissions for attaching a new child for the 521 * given @role. 522 * 523 * If @reopen_queue is non-NULL, don't return the currently needed 524 * permissions, but those that will be needed after applying the 525 * @reopen_queue. 526 */ 527 void (*bdrv_child_perm)(BlockDriverState *bs, BdrvChild *c, 528 const BdrvChildRole *role, 529 BlockReopenQueue *reopen_queue, 530 uint64_t parent_perm, uint64_t parent_shared, 531 uint64_t *nperm, uint64_t *nshared); 532 533 /** 534 * Bitmaps should be marked as 'IN_USE' in the image on reopening image 535 * as rw. This handler should realize it. It also should unset readonly 536 * field of BlockDirtyBitmap's in case of success. 537 */ 538 int (*bdrv_reopen_bitmaps_rw)(BlockDriverState *bs, Error **errp); 539 bool (*bdrv_can_store_new_dirty_bitmap)(BlockDriverState *bs, 540 const char *name, 541 uint32_t granularity, 542 Error **errp); 543 void (*bdrv_remove_persistent_dirty_bitmap)(BlockDriverState *bs, 544 const char *name, 545 Error **errp); 546 547 /** 548 * Register/unregister a buffer for I/O. For example, when the driver is 549 * interested to know the memory areas that will later be used in iovs, so 550 * that it can do IOMMU mapping with VFIO etc., in order to get better 551 * performance. In the case of VFIO drivers, this callback is used to do 552 * DMA mapping for hot buffers. 553 */ 554 void (*bdrv_register_buf)(BlockDriverState *bs, void *host, size_t size); 555 void (*bdrv_unregister_buf)(BlockDriverState *bs, void *host); 556 QLIST_ENTRY(BlockDriver) list; 557 558 /* Pointer to a NULL-terminated array of names of strong options 559 * that can be specified for bdrv_open(). A strong option is one 560 * that changes the data of a BDS. 561 * If this pointer is NULL, the array is considered empty. 562 * "filename" and "driver" are always considered strong. */ 563 const char *const *strong_runtime_opts; 564 }; 565 566 typedef struct BlockLimits { 567 /* Alignment requirement, in bytes, for offset/length of I/O 568 * requests. Must be a power of 2 less than INT_MAX; defaults to 569 * 1 for drivers with modern byte interfaces, and to 512 570 * otherwise. */ 571 uint32_t request_alignment; 572 573 /* Maximum number of bytes that can be discarded at once (since it 574 * is signed, it must be < 2G, if set). Must be multiple of 575 * pdiscard_alignment, but need not be power of 2. May be 0 if no 576 * inherent 32-bit limit */ 577 int32_t max_pdiscard; 578 579 /* Optimal alignment for discard requests in bytes. A power of 2 580 * is best but not mandatory. Must be a multiple of 581 * bl.request_alignment, and must be less than max_pdiscard if 582 * that is set. May be 0 if bl.request_alignment is good enough */ 583 uint32_t pdiscard_alignment; 584 585 /* Maximum number of bytes that can zeroized at once (since it is 586 * signed, it must be < 2G, if set). Must be multiple of 587 * pwrite_zeroes_alignment. May be 0 if no inherent 32-bit limit */ 588 int32_t max_pwrite_zeroes; 589 590 /* Optimal alignment for write zeroes requests in bytes. A power 591 * of 2 is best but not mandatory. Must be a multiple of 592 * bl.request_alignment, and must be less than max_pwrite_zeroes 593 * if that is set. May be 0 if bl.request_alignment is good 594 * enough */ 595 uint32_t pwrite_zeroes_alignment; 596 597 /* Optimal transfer length in bytes. A power of 2 is best but not 598 * mandatory. Must be a multiple of bl.request_alignment, or 0 if 599 * no preferred size */ 600 uint32_t opt_transfer; 601 602 /* Maximal transfer length in bytes. Need not be power of 2, but 603 * must be multiple of opt_transfer and bl.request_alignment, or 0 604 * for no 32-bit limit. For now, anything larger than INT_MAX is 605 * clamped down. */ 606 uint32_t max_transfer; 607 608 /* memory alignment, in bytes so that no bounce buffer is needed */ 609 size_t min_mem_alignment; 610 611 /* memory alignment, in bytes, for bounce buffer */ 612 size_t opt_mem_alignment; 613 614 /* maximum number of iovec elements */ 615 int max_iov; 616 } BlockLimits; 617 618 typedef struct BdrvOpBlocker BdrvOpBlocker; 619 620 typedef struct BdrvAioNotifier { 621 void (*attached_aio_context)(AioContext *new_context, void *opaque); 622 void (*detach_aio_context)(void *opaque); 623 624 void *opaque; 625 bool deleted; 626 627 QLIST_ENTRY(BdrvAioNotifier) list; 628 } BdrvAioNotifier; 629 630 struct BdrvChildRole { 631 /* If true, bdrv_replace_node() doesn't change the node this BdrvChild 632 * points to. */ 633 bool stay_at_node; 634 635 /* If true, the parent is a BlockDriverState and bdrv_next_all_states() 636 * will return it. This information is used for drain_all, where every node 637 * will be drained separately, so the drain only needs to be propagated to 638 * non-BDS parents. */ 639 bool parent_is_bds; 640 641 void (*inherit_options)(int *child_flags, QDict *child_options, 642 int parent_flags, QDict *parent_options); 643 644 void (*change_media)(BdrvChild *child, bool load); 645 void (*resize)(BdrvChild *child); 646 647 /* Returns a name that is supposedly more useful for human users than the 648 * node name for identifying the node in question (in particular, a BB 649 * name), or NULL if the parent can't provide a better name. */ 650 const char *(*get_name)(BdrvChild *child); 651 652 /* Returns a malloced string that describes the parent of the child for a 653 * human reader. This could be a node-name, BlockBackend name, qdev ID or 654 * QOM path of the device owning the BlockBackend, job type and ID etc. The 655 * caller is responsible for freeing the memory. */ 656 char *(*get_parent_desc)(BdrvChild *child); 657 658 /* 659 * If this pair of functions is implemented, the parent doesn't issue new 660 * requests after returning from .drained_begin() until .drained_end() is 661 * called. 662 * 663 * These functions must not change the graph (and therefore also must not 664 * call aio_poll(), which could change the graph indirectly). 665 * 666 * If drained_end() schedules background operations, it must atomically 667 * increment *drained_end_counter for each such operation and atomically 668 * decrement it once the operation has settled. 669 * 670 * Note that this can be nested. If drained_begin() was called twice, new 671 * I/O is allowed only after drained_end() was called twice, too. 672 */ 673 void (*drained_begin)(BdrvChild *child); 674 void (*drained_end)(BdrvChild *child, int *drained_end_counter); 675 676 /* 677 * Returns whether the parent has pending requests for the child. This 678 * callback is polled after .drained_begin() has been called until all 679 * activity on the child has stopped. 680 */ 681 bool (*drained_poll)(BdrvChild *child); 682 683 /* Notifies the parent that the child has been activated/inactivated (e.g. 684 * when migration is completing) and it can start/stop requesting 685 * permissions and doing I/O on it. */ 686 void (*activate)(BdrvChild *child, Error **errp); 687 int (*inactivate)(BdrvChild *child); 688 689 void (*attach)(BdrvChild *child); 690 void (*detach)(BdrvChild *child); 691 692 /* Notifies the parent that the filename of its child has changed (e.g. 693 * because the direct child was removed from the backing chain), so that it 694 * can update its reference. */ 695 int (*update_filename)(BdrvChild *child, BlockDriverState *new_base, 696 const char *filename, Error **errp); 697 698 bool (*can_set_aio_ctx)(BdrvChild *child, AioContext *ctx, 699 GSList **ignore, Error **errp); 700 void (*set_aio_ctx)(BdrvChild *child, AioContext *ctx, GSList **ignore); 701 }; 702 703 extern const BdrvChildRole child_file; 704 extern const BdrvChildRole child_format; 705 extern const BdrvChildRole child_backing; 706 707 struct BdrvChild { 708 BlockDriverState *bs; 709 char *name; 710 const BdrvChildRole *role; 711 void *opaque; 712 713 /** 714 * Granted permissions for operating on this BdrvChild (BLK_PERM_* bitmask) 715 */ 716 uint64_t perm; 717 718 /** 719 * Permissions that can still be granted to other users of @bs while this 720 * BdrvChild is still attached to it. (BLK_PERM_* bitmask) 721 */ 722 uint64_t shared_perm; 723 724 /* backup of permissions during permission update procedure */ 725 bool has_backup_perm; 726 uint64_t backup_perm; 727 uint64_t backup_shared_perm; 728 729 /* 730 * This link is frozen: the child can neither be replaced nor 731 * detached from the parent. 732 */ 733 bool frozen; 734 735 /* 736 * How many times the parent of this child has been drained 737 * (through role->drained_*). 738 * Usually, this is equal to bs->quiesce_counter (potentially 739 * reduced by bdrv_drain_all_count). It may differ while the 740 * child is entering or leaving a drained section. 741 */ 742 int parent_quiesce_counter; 743 744 QLIST_ENTRY(BdrvChild) next; 745 QLIST_ENTRY(BdrvChild) next_parent; 746 }; 747 748 /* 749 * Note: the function bdrv_append() copies and swaps contents of 750 * BlockDriverStates, so if you add new fields to this struct, please 751 * inspect bdrv_append() to determine if the new fields need to be 752 * copied as well. 753 */ 754 struct BlockDriverState { 755 /* Protected by big QEMU lock or read-only after opening. No special 756 * locking needed during I/O... 757 */ 758 int open_flags; /* flags used to open the file, re-used for re-open */ 759 bool read_only; /* if true, the media is read only */ 760 bool encrypted; /* if true, the media is encrypted */ 761 bool sg; /* if true, the device is a /dev/sg* */ 762 bool probed; /* if true, format was probed rather than specified */ 763 bool force_share; /* if true, always allow all shared permissions */ 764 bool implicit; /* if true, this filter node was automatically inserted */ 765 766 BlockDriver *drv; /* NULL means no media */ 767 void *opaque; 768 769 AioContext *aio_context; /* event loop used for fd handlers, timers, etc */ 770 /* long-running tasks intended to always use the same AioContext as this 771 * BDS may register themselves in this list to be notified of changes 772 * regarding this BDS's context */ 773 QLIST_HEAD(, BdrvAioNotifier) aio_notifiers; 774 bool walking_aio_notifiers; /* to make removal during iteration safe */ 775 776 char filename[PATH_MAX]; 777 char backing_file[PATH_MAX]; /* if non zero, the image is a diff of 778 this file image */ 779 /* The backing filename indicated by the image header; if we ever 780 * open this file, then this is replaced by the resulting BDS's 781 * filename (i.e. after a bdrv_refresh_filename() run). */ 782 char auto_backing_file[PATH_MAX]; 783 char backing_format[16]; /* if non-zero and backing_file exists */ 784 785 QDict *full_open_options; 786 char exact_filename[PATH_MAX]; 787 788 BdrvChild *backing; 789 BdrvChild *file; 790 791 /* I/O Limits */ 792 BlockLimits bl; 793 794 /* Flags honored during pwrite (so far: BDRV_REQ_FUA, 795 * BDRV_REQ_WRITE_UNCHANGED). 796 * If a driver does not support BDRV_REQ_WRITE_UNCHANGED, those 797 * writes will be issued as normal writes without the flag set. 798 * This is important to note for drivers that do not explicitly 799 * request a WRITE permission for their children and instead take 800 * the same permissions as their parent did (this is commonly what 801 * block filters do). Such drivers have to be aware that the 802 * parent may have taken a WRITE_UNCHANGED permission only and is 803 * issuing such requests. Drivers either must make sure that 804 * these requests do not result in plain WRITE accesses (usually 805 * by supporting BDRV_REQ_WRITE_UNCHANGED, and then forwarding 806 * every incoming write request as-is, including potentially that 807 * flag), or they have to explicitly take the WRITE permission for 808 * their children. */ 809 unsigned int supported_write_flags; 810 /* Flags honored during pwrite_zeroes (so far: BDRV_REQ_FUA, 811 * BDRV_REQ_MAY_UNMAP, BDRV_REQ_WRITE_UNCHANGED) */ 812 unsigned int supported_zero_flags; 813 814 /* the following member gives a name to every node on the bs graph. */ 815 char node_name[32]; 816 /* element of the list of named nodes building the graph */ 817 QTAILQ_ENTRY(BlockDriverState) node_list; 818 /* element of the list of all BlockDriverStates (all_bdrv_states) */ 819 QTAILQ_ENTRY(BlockDriverState) bs_list; 820 /* element of the list of monitor-owned BDS */ 821 QTAILQ_ENTRY(BlockDriverState) monitor_list; 822 int refcnt; 823 824 /* operation blockers */ 825 QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX]; 826 827 /* The node that this node inherited default options from (and a reopen on 828 * which can affect this node by changing these defaults). This is always a 829 * parent node of this node. */ 830 BlockDriverState *inherits_from; 831 QLIST_HEAD(, BdrvChild) children; 832 QLIST_HEAD(, BdrvChild) parents; 833 834 QDict *options; 835 QDict *explicit_options; 836 BlockdevDetectZeroesOptions detect_zeroes; 837 838 /* The error object in use for blocking operations on backing_hd */ 839 Error *backing_blocker; 840 841 /* Protected by AioContext lock */ 842 843 /* If we are reading a disk image, give its size in sectors. 844 * Generally read-only; it is written to by load_snapshot and 845 * save_snaphost, but the block layer is quiescent during those. 846 */ 847 int64_t total_sectors; 848 849 /* Callback before write request is processed */ 850 NotifierWithReturnList before_write_notifiers; 851 852 /* threshold limit for writes, in bytes. "High water mark". */ 853 uint64_t write_threshold_offset; 854 NotifierWithReturn write_threshold_notifier; 855 856 /* Writing to the list requires the BQL _and_ the dirty_bitmap_mutex. 857 * Reading from the list can be done with either the BQL or the 858 * dirty_bitmap_mutex. Modifying a bitmap only requires 859 * dirty_bitmap_mutex. */ 860 QemuMutex dirty_bitmap_mutex; 861 QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps; 862 863 /* Offset after the highest byte written to */ 864 Stat64 wr_highest_offset; 865 866 /* If true, copy read backing sectors into image. Can be >1 if more 867 * than one client has requested copy-on-read. Accessed with atomic 868 * ops. 869 */ 870 int copy_on_read; 871 872 /* number of in-flight requests; overall and serialising. 873 * Accessed with atomic ops. 874 */ 875 unsigned int in_flight; 876 unsigned int serialising_in_flight; 877 878 /* counter for nested bdrv_io_plug. 879 * Accessed with atomic ops. 880 */ 881 unsigned io_plugged; 882 883 /* do we need to tell the quest if we have a volatile write cache? */ 884 int enable_write_cache; 885 886 /* Accessed with atomic ops. */ 887 int quiesce_counter; 888 int recursive_quiesce_counter; 889 890 unsigned int write_gen; /* Current data generation */ 891 892 /* Protected by reqs_lock. */ 893 CoMutex reqs_lock; 894 QLIST_HEAD(, BdrvTrackedRequest) tracked_requests; 895 CoQueue flush_queue; /* Serializing flush queue */ 896 bool active_flush_req; /* Flush request in flight? */ 897 898 /* Only read/written by whoever has set active_flush_req to true. */ 899 unsigned int flushed_gen; /* Flushed write generation */ 900 901 /* BdrvChild links to this node may never be frozen */ 902 bool never_freeze; 903 }; 904 905 struct BlockBackendRootState { 906 int open_flags; 907 bool read_only; 908 BlockdevDetectZeroesOptions detect_zeroes; 909 }; 910 911 typedef enum BlockMirrorBackingMode { 912 /* Reuse the existing backing chain from the source for the target. 913 * - sync=full: Set backing BDS to NULL. 914 * - sync=top: Use source's backing BDS. 915 * - sync=none: Use source as the backing BDS. */ 916 MIRROR_SOURCE_BACKING_CHAIN, 917 918 /* Open the target's backing chain completely anew */ 919 MIRROR_OPEN_BACKING_CHAIN, 920 921 /* Do not change the target's backing BDS after job completion */ 922 MIRROR_LEAVE_BACKING_CHAIN, 923 } BlockMirrorBackingMode; 924 925 static inline BlockDriverState *backing_bs(BlockDriverState *bs) 926 { 927 return bs->backing ? bs->backing->bs : NULL; 928 } 929 930 931 /* Essential block drivers which must always be statically linked into qemu, and 932 * which therefore can be accessed without using bdrv_find_format() */ 933 extern BlockDriver bdrv_file; 934 extern BlockDriver bdrv_raw; 935 extern BlockDriver bdrv_qcow2; 936 937 int coroutine_fn bdrv_co_preadv(BdrvChild *child, 938 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 939 BdrvRequestFlags flags); 940 int coroutine_fn bdrv_co_pwritev(BdrvChild *child, 941 int64_t offset, unsigned int bytes, QEMUIOVector *qiov, 942 BdrvRequestFlags flags); 943 944 static inline int coroutine_fn bdrv_co_pread(BdrvChild *child, 945 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags) 946 { 947 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); 948 949 return bdrv_co_preadv(child, offset, bytes, &qiov, flags); 950 } 951 952 static inline int coroutine_fn bdrv_co_pwrite(BdrvChild *child, 953 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags) 954 { 955 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); 956 957 return bdrv_co_pwritev(child, offset, bytes, &qiov, flags); 958 } 959 960 extern unsigned int bdrv_drain_all_count; 961 void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent); 962 void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent); 963 964 int get_tmp_filename(char *filename, int size); 965 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, 966 const char *filename); 967 968 void bdrv_parse_filename_strip_prefix(const char *filename, const char *prefix, 969 QDict *options); 970 971 972 /** 973 * bdrv_add_before_write_notifier: 974 * 975 * Register a callback that is invoked before write requests are processed but 976 * after any throttling or waiting for overlapping requests. 977 */ 978 void bdrv_add_before_write_notifier(BlockDriverState *bs, 979 NotifierWithReturn *notifier); 980 981 /** 982 * bdrv_add_aio_context_notifier: 983 * 984 * If a long-running job intends to be always run in the same AioContext as a 985 * certain BDS, it may use this function to be notified of changes regarding the 986 * association of the BDS to an AioContext. 987 * 988 * attached_aio_context() is called after the target BDS has been attached to a 989 * new AioContext; detach_aio_context() is called before the target BDS is being 990 * detached from its old AioContext. 991 */ 992 void bdrv_add_aio_context_notifier(BlockDriverState *bs, 993 void (*attached_aio_context)(AioContext *new_context, void *opaque), 994 void (*detach_aio_context)(void *opaque), void *opaque); 995 996 /** 997 * bdrv_remove_aio_context_notifier: 998 * 999 * Unsubscribe of change notifications regarding the BDS's AioContext. The 1000 * parameters given here have to be the same as those given to 1001 * bdrv_add_aio_context_notifier(). 1002 */ 1003 void bdrv_remove_aio_context_notifier(BlockDriverState *bs, 1004 void (*aio_context_attached)(AioContext *, 1005 void *), 1006 void (*aio_context_detached)(void *), 1007 void *opaque); 1008 1009 /** 1010 * bdrv_wakeup: 1011 * @bs: The BlockDriverState for which an I/O operation has been completed. 1012 * 1013 * Wake up the main thread if it is waiting on BDRV_POLL_WHILE. During 1014 * synchronous I/O on a BlockDriverState that is attached to another 1015 * I/O thread, the main thread lets the I/O thread's event loop run, 1016 * waiting for the I/O operation to complete. A bdrv_wakeup will wake 1017 * up the main thread if necessary. 1018 * 1019 * Manual calls to bdrv_wakeup are rarely necessary, because 1020 * bdrv_dec_in_flight already calls it. 1021 */ 1022 void bdrv_wakeup(BlockDriverState *bs); 1023 1024 #ifdef _WIN32 1025 int is_windows_drive(const char *filename); 1026 #endif 1027 1028 /** 1029 * stream_start: 1030 * @job_id: The id of the newly-created job, or %NULL to use the 1031 * device name of @bs. 1032 * @bs: Block device to operate on. 1033 * @base: Block device that will become the new base, or %NULL to 1034 * flatten the whole backing file chain onto @bs. 1035 * @backing_file_str: The file name that will be written to @bs as the 1036 * the new backing file if the job completes. Ignored if @base is %NULL. 1037 * @creation_flags: Flags that control the behavior of the Job lifetime. 1038 * See @BlockJobCreateFlags 1039 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1040 * @on_error: The action to take upon error. 1041 * @errp: Error object. 1042 * 1043 * Start a streaming operation on @bs. Clusters that are unallocated 1044 * in @bs, but allocated in any image between @base and @bs (both 1045 * exclusive) will be written to @bs. At the end of a successful 1046 * streaming job, the backing file of @bs will be changed to 1047 * @backing_file_str in the written image and to @base in the live 1048 * BlockDriverState. 1049 */ 1050 void stream_start(const char *job_id, BlockDriverState *bs, 1051 BlockDriverState *base, const char *backing_file_str, 1052 int creation_flags, int64_t speed, 1053 BlockdevOnError on_error, Error **errp); 1054 1055 /** 1056 * commit_start: 1057 * @job_id: The id of the newly-created job, or %NULL to use the 1058 * device name of @bs. 1059 * @bs: Active block device. 1060 * @top: Top block device to be committed. 1061 * @base: Block device that will be written into, and become the new top. 1062 * @creation_flags: Flags that control the behavior of the Job lifetime. 1063 * See @BlockJobCreateFlags 1064 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1065 * @on_error: The action to take upon error. 1066 * @backing_file_str: String to use as the backing file in @top's overlay 1067 * @filter_node_name: The node name that should be assigned to the filter 1068 * driver that the commit job inserts into the graph above @top. NULL means 1069 * that a node name should be autogenerated. 1070 * @errp: Error object. 1071 * 1072 */ 1073 void commit_start(const char *job_id, BlockDriverState *bs, 1074 BlockDriverState *base, BlockDriverState *top, 1075 int creation_flags, int64_t speed, 1076 BlockdevOnError on_error, const char *backing_file_str, 1077 const char *filter_node_name, Error **errp); 1078 /** 1079 * commit_active_start: 1080 * @job_id: The id of the newly-created job, or %NULL to use the 1081 * device name of @bs. 1082 * @bs: Active block device to be committed. 1083 * @base: Block device that will be written into, and become the new top. 1084 * @creation_flags: Flags that control the behavior of the Job lifetime. 1085 * See @BlockJobCreateFlags 1086 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1087 * @on_error: The action to take upon error. 1088 * @filter_node_name: The node name that should be assigned to the filter 1089 * driver that the commit job inserts into the graph above @bs. NULL means that 1090 * a node name should be autogenerated. 1091 * @cb: Completion function for the job. 1092 * @opaque: Opaque pointer value passed to @cb. 1093 * @auto_complete: Auto complete the job. 1094 * @errp: Error object. 1095 * 1096 */ 1097 BlockJob *commit_active_start(const char *job_id, BlockDriverState *bs, 1098 BlockDriverState *base, int creation_flags, 1099 int64_t speed, BlockdevOnError on_error, 1100 const char *filter_node_name, 1101 BlockCompletionFunc *cb, void *opaque, 1102 bool auto_complete, Error **errp); 1103 /* 1104 * mirror_start: 1105 * @job_id: The id of the newly-created job, or %NULL to use the 1106 * device name of @bs. 1107 * @bs: Block device to operate on. 1108 * @target: Block device to write to. 1109 * @replaces: Block graph node name to replace once the mirror is done. Can 1110 * only be used when full mirroring is selected. 1111 * @creation_flags: Flags that control the behavior of the Job lifetime. 1112 * See @BlockJobCreateFlags 1113 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1114 * @granularity: The chosen granularity for the dirty bitmap. 1115 * @buf_size: The amount of data that can be in flight at one time. 1116 * @mode: Whether to collapse all images in the chain to the target. 1117 * @backing_mode: How to establish the target's backing chain after completion. 1118 * @on_source_error: The action to take upon error reading from the source. 1119 * @on_target_error: The action to take upon error writing to the target. 1120 * @unmap: Whether to unmap target where source sectors only contain zeroes. 1121 * @filter_node_name: The node name that should be assigned to the filter 1122 * driver that the mirror job inserts into the graph above @bs. NULL means that 1123 * a node name should be autogenerated. 1124 * @copy_mode: When to trigger writes to the target. 1125 * @errp: Error object. 1126 * 1127 * Start a mirroring operation on @bs. Clusters that are allocated 1128 * in @bs will be written to @target until the job is cancelled or 1129 * manually completed. At the end of a successful mirroring job, 1130 * @bs will be switched to read from @target. 1131 */ 1132 void mirror_start(const char *job_id, BlockDriverState *bs, 1133 BlockDriverState *target, const char *replaces, 1134 int creation_flags, int64_t speed, 1135 uint32_t granularity, int64_t buf_size, 1136 MirrorSyncMode mode, BlockMirrorBackingMode backing_mode, 1137 BlockdevOnError on_source_error, 1138 BlockdevOnError on_target_error, 1139 bool unmap, const char *filter_node_name, 1140 MirrorCopyMode copy_mode, Error **errp); 1141 1142 /* 1143 * backup_job_create: 1144 * @job_id: The id of the newly-created job, or %NULL to use the 1145 * device name of @bs. 1146 * @bs: Block device to operate on. 1147 * @target: Block device to write to. 1148 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 1149 * @sync_mode: What parts of the disk image should be copied to the destination. 1150 * @sync_bitmap: The dirty bitmap if sync_mode is MIRROR_SYNC_MODE_INCREMENTAL. 1151 * @on_source_error: The action to take upon error reading from the source. 1152 * @on_target_error: The action to take upon error writing to the target. 1153 * @creation_flags: Flags that control the behavior of the Job lifetime. 1154 * See @BlockJobCreateFlags 1155 * @cb: Completion function for the job. 1156 * @opaque: Opaque pointer value passed to @cb. 1157 * @txn: Transaction that this job is part of (may be NULL). 1158 * 1159 * Create a backup operation on @bs. Clusters in @bs are written to @target 1160 * until the job is cancelled or manually completed. 1161 */ 1162 BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, 1163 BlockDriverState *target, int64_t speed, 1164 MirrorSyncMode sync_mode, 1165 BdrvDirtyBitmap *sync_bitmap, 1166 bool compress, 1167 BlockdevOnError on_source_error, 1168 BlockdevOnError on_target_error, 1169 int creation_flags, 1170 BlockCompletionFunc *cb, void *opaque, 1171 JobTxn *txn, Error **errp); 1172 1173 void hmp_drive_add_node(Monitor *mon, const char *optstr); 1174 1175 BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, 1176 const char *child_name, 1177 const BdrvChildRole *child_role, 1178 AioContext *ctx, 1179 uint64_t perm, uint64_t shared_perm, 1180 void *opaque, Error **errp); 1181 void bdrv_root_unref_child(BdrvChild *child); 1182 1183 /** 1184 * Sets a BdrvChild's permissions. Avoid if the parent is a BDS; use 1185 * bdrv_child_refresh_perms() instead and make the parent's 1186 * .bdrv_child_perm() implementation return the correct values. 1187 */ 1188 int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, 1189 Error **errp); 1190 1191 /** 1192 * Calls bs->drv->bdrv_child_perm() and updates the child's permission 1193 * masks with the result. 1194 * Drivers should invoke this function whenever an event occurs that 1195 * makes their .bdrv_child_perm() implementation return different 1196 * values than before, but which will not result in the block layer 1197 * automatically refreshing the permissions. 1198 */ 1199 int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp); 1200 1201 /* Default implementation for BlockDriver.bdrv_child_perm() that can be used by 1202 * block filters: Forward CONSISTENT_READ, WRITE, WRITE_UNCHANGED and RESIZE to 1203 * all children */ 1204 void bdrv_filter_default_perms(BlockDriverState *bs, BdrvChild *c, 1205 const BdrvChildRole *role, 1206 BlockReopenQueue *reopen_queue, 1207 uint64_t perm, uint64_t shared, 1208 uint64_t *nperm, uint64_t *nshared); 1209 1210 /* Default implementation for BlockDriver.bdrv_child_perm() that can be used by 1211 * (non-raw) image formats: Like above for bs->backing, but for bs->file it 1212 * requires WRITE | RESIZE for read-write images, always requires 1213 * CONSISTENT_READ and doesn't share WRITE. */ 1214 void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c, 1215 const BdrvChildRole *role, 1216 BlockReopenQueue *reopen_queue, 1217 uint64_t perm, uint64_t shared, 1218 uint64_t *nperm, uint64_t *nshared); 1219 1220 /* 1221 * Default implementation for drivers to pass bdrv_co_block_status() to 1222 * their file. 1223 */ 1224 int coroutine_fn bdrv_co_block_status_from_file(BlockDriverState *bs, 1225 bool want_zero, 1226 int64_t offset, 1227 int64_t bytes, 1228 int64_t *pnum, 1229 int64_t *map, 1230 BlockDriverState **file); 1231 /* 1232 * Default implementation for drivers to pass bdrv_co_block_status() to 1233 * their backing file. 1234 */ 1235 int coroutine_fn bdrv_co_block_status_from_backing(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 const char *bdrv_get_parent_name(const BlockDriverState *bs); 1243 void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp); 1244 bool blk_dev_has_removable_media(BlockBackend *blk); 1245 bool blk_dev_has_tray(BlockBackend *blk); 1246 void blk_dev_eject_request(BlockBackend *blk, bool force); 1247 bool blk_dev_is_tray_open(BlockBackend *blk); 1248 bool blk_dev_is_medium_locked(BlockBackend *blk); 1249 1250 void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes); 1251 1252 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out); 1253 void bdrv_restore_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *backup); 1254 1255 void bdrv_inc_in_flight(BlockDriverState *bs); 1256 void bdrv_dec_in_flight(BlockDriverState *bs); 1257 1258 void blockdev_close_all_bdrv_states(void); 1259 1260 int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, uint64_t src_offset, 1261 BdrvChild *dst, uint64_t dst_offset, 1262 uint64_t bytes, 1263 BdrvRequestFlags read_flags, 1264 BdrvRequestFlags write_flags); 1265 int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, uint64_t src_offset, 1266 BdrvChild *dst, uint64_t dst_offset, 1267 uint64_t bytes, 1268 BdrvRequestFlags read_flags, 1269 BdrvRequestFlags write_flags); 1270 1271 int refresh_total_sectors(BlockDriverState *bs, int64_t hint); 1272 1273 #endif /* BLOCK_INT_H */ 1274