include/block/block_int.h

   1 /*
   2  * QEMU System Emulator block driver
   3  *
   4  * Copyright (c) 2003 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #ifndef BLOCK_INT_H
  25 #define BLOCK_INT_H
  26
  27 #include "block/accounting.h"
  28 #include "block/block.h"
  29 #include "qemu/option.h"
  30 #include "qemu/queue.h"
  31 #include "block/coroutine.h"
  32 #include "qemu/timer.h"
  33 #include "qapi-types.h"
  34 #include "qapi/qmp/qerror.h"
  35 #include "monitor/monitor.h"
  36 #include "qemu/hbitmap.h"
  37 #include "block/snapshot.h"
  38 #include "qemu/main-loop.h"
  39 #include "qemu/throttle.h"
  40
  41 #define BLOCK_FLAG_ENCRYPT          1
  42 #define BLOCK_FLAG_COMPAT6          4
  43 #define BLOCK_FLAG_LAZY_REFCOUNTS   8
  44
  45 #define BLOCK_OPT_SIZE              "size"
  46 #define BLOCK_OPT_ENCRYPT           "encryption"
  47 #define BLOCK_OPT_COMPAT6           "compat6"
  48 #define BLOCK_OPT_BACKING_FILE      "backing_file"
  49 #define BLOCK_OPT_BACKING_FMT       "backing_fmt"
  50 #define BLOCK_OPT_CLUSTER_SIZE      "cluster_size"
  51 #define BLOCK_OPT_TABLE_SIZE        "table_size"
  52 #define BLOCK_OPT_PREALLOC          "preallocation"
  53 #define BLOCK_OPT_SUBFMT            "subformat"
  54 #define BLOCK_OPT_COMPAT_LEVEL      "compat"
  55 #define BLOCK_OPT_LAZY_REFCOUNTS    "lazy_refcounts"
  56 #define BLOCK_OPT_ADAPTER_TYPE      "adapter_type"
  57 #define BLOCK_OPT_REDUNDANCY        "redundancy"
  58 #define BLOCK_OPT_NOCOW             "nocow"
  59 #define BLOCK_OPT_OBJECT_SIZE       "object_size"
  60 #define BLOCK_OPT_REFCOUNT_BITS     "refcount_bits"
  61
  62 #define BLOCK_PROBE_BUF_SIZE        512
  63
  64 typedef struct BdrvTrackedRequest {
  65     BlockDriverState *bs;
  66     int64_t offset;
  67     unsigned int bytes;
  68     bool is_write;
  69
  70     bool serialising;
  71     int64_t overlap_offset;
  72     unsigned int overlap_bytes;
  73
  74     QLIST_ENTRY(BdrvTrackedRequest) list;
  75     Coroutine *co; /* owner, used for deadlock detection */
  76     CoQueue wait_queue; /* coroutines blocked on this request */
  77
  78     struct BdrvTrackedRequest *waiting_for;
  79 } BdrvTrackedRequest;
  80
  81 struct BlockDriver {
  82     const char *format_name;
  83     int instance_size;
  84
  85     /* set to true if the BlockDriver is a block filter */
  86     bool is_filter;
  87     /* for snapshots block filter like Quorum can implement the
  88      * following recursive callback.
  89      * It's purpose is to recurse on the filter children while calling
  90      * bdrv_recurse_is_first_non_filter on them.
  91      * For a sample implementation look in the future Quorum block filter.
  92      */
  93     bool (*bdrv_recurse_is_first_non_filter)(BlockDriverState *bs,
  94                                              BlockDriverState *candidate);
  95
  96     int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename);
  97     int (*bdrv_probe_device)(const char *filename);
  98
  99     /* Any driver implementing this callback is expected to be able to handle
 100      * NULL file names in its .bdrv_open() implementation */
 101     void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp);
 102     /* Drivers not implementing bdrv_parse_filename nor bdrv_open should have
 103      * this field set to true, except ones that are defined only by their
 104      * child's bs.
 105      * An example of the last type will be the quorum block driver.
 106      */
 107     bool bdrv_needs_filename;
 108
 109     /* Set if a driver can support backing files */
 110     bool supports_backing;
 111
 112     /* For handling image reopen for split or non-split files */
 113     int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state,
 114                                BlockReopenQueue *queue, Error **errp);
 115     void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state);
 116     void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state);
 117
 118     int (*bdrv_open)(BlockDriverState *bs, QDict *options, int flags,
 119                      Error **errp);
 120     int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags,
 121                           Error **errp);
 122     int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num,
 123                      uint8_t *buf, int nb_sectors);
 124     int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num,
 125                       const uint8_t *buf, int nb_sectors);
 126     void (*bdrv_close)(BlockDriverState *bs);
 127     void (*bdrv_rebind)(BlockDriverState *bs);
 128     int (*bdrv_create)(const char *filename, QemuOpts *opts, Error **errp);
 129     int (*bdrv_set_key)(BlockDriverState *bs, const char *key);
 130     int (*bdrv_make_empty)(BlockDriverState *bs);
 131
 132     void (*bdrv_refresh_filename)(BlockDriverState *bs);
 133
 134     /* aio */
 135     BlockAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs,
 136         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 137         BlockCompletionFunc *cb, void *opaque);
 138     BlockAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs,
 139         int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
 140         BlockCompletionFunc *cb, void *opaque);
 141     BlockAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs,
 142         BlockCompletionFunc *cb, void *opaque);
 143     BlockAIOCB *(*bdrv_aio_discard)(BlockDriverState *bs,
 144         int64_t sector_num, int nb_sectors,
 145         BlockCompletionFunc *cb, void *opaque);
 146
 147     int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs,
 148         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
 149     int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs,
 150         int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
 151     /*
 152      * Efficiently zero a region of the disk image.  Typically an image format
 153      * would use a compact metadata representation to implement this.  This
 154      * function pointer may be NULL and .bdrv_co_writev() will be called
 155      * instead.
 156      */
 157     int coroutine_fn (*bdrv_co_write_zeroes)(BlockDriverState *bs,
 158         int64_t sector_num, int nb_sectors, BdrvRequestFlags flags);
 159     int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs,
 160         int64_t sector_num, int nb_sectors);
 161     int64_t coroutine_fn (*bdrv_co_get_block_status)(BlockDriverState *bs,
 162         int64_t sector_num, int nb_sectors, int *pnum);
 163
 164     /*
 165      * Invalidate any cached meta-data.
 166      */
 167     void (*bdrv_invalidate_cache)(BlockDriverState *bs, Error **errp);
 168
 169     /*
 170      * Flushes all data that was already written to the OS all the way down to
 171      * the disk (for example raw-posix calls fsync()).
 172      */
 173     int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs);
 174
 175     /*
 176      * Flushes all internal caches to the OS. The data may still sit in a
 177      * writeback cache of the host OS, but it will survive a crash of the qemu
 178      * process.
 179      */
 180     int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs);
 181
 182     const char *protocol_name;
 183     int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset);
 184
 185     int64_t (*bdrv_getlength)(BlockDriverState *bs);
 186     bool has_variable_length;
 187     int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs);
 188
 189     int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num,
 190                                  const uint8_t *buf, int nb_sectors);
 191
 192     int (*bdrv_snapshot_create)(BlockDriverState *bs,
 193                                 QEMUSnapshotInfo *sn_info);
 194     int (*bdrv_snapshot_goto)(BlockDriverState *bs,
 195                               const char *snapshot_id);
 196     int (*bdrv_snapshot_delete)(BlockDriverState *bs,
 197                                 const char *snapshot_id,
 198                                 const char *name,
 199                                 Error **errp);
 200     int (*bdrv_snapshot_list)(BlockDriverState *bs,
 201                               QEMUSnapshotInfo **psn_info);
 202     int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs,
 203                                   const char *snapshot_id,
 204                                   const char *name,
 205                                   Error **errp);
 206     int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
 207     ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs);
 208
 209     int (*bdrv_save_vmstate)(BlockDriverState *bs, QEMUIOVector *qiov,
 210                              int64_t pos);
 211     int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf,
 212                              int64_t pos, int size);
 213
 214     int (*bdrv_change_backing_file)(BlockDriverState *bs,
 215         const char *backing_file, const char *backing_fmt);
 216
 217     /* removable device specific */
 218     int (*bdrv_is_inserted)(BlockDriverState *bs);
 219     int (*bdrv_media_changed)(BlockDriverState *bs);
 220     void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag);
 221     void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked);
 222
 223     /* to control generic scsi devices */
 224     int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf);
 225     BlockAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
 226         unsigned long int req, void *buf,
 227         BlockCompletionFunc *cb, void *opaque);
 228
 229     /* List of options for creating images, terminated by name == NULL */
 230     QemuOptsList *create_opts;
 231
 232     /*
 233      * Returns 0 for completed check, -errno for internal errors.
 234      * The check results are stored in result.
 235      */
 236     int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result,
 237         BdrvCheckMode fix);
 238
 239     int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts,
 240                               BlockDriverAmendStatusCB *status_cb);
 241
 242     void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);
 243
 244     /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */
 245     int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event,
 246         const char *tag);
 247     int (*bdrv_debug_remove_breakpoint)(BlockDriverState *bs,
 248         const char *tag);
 249     int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag);
 250     bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag);
 251
 252     void (*bdrv_refresh_limits)(BlockDriverState *bs, Error **errp);
 253
 254     /*
 255      * Returns 1 if newly created images are guaranteed to contain only
 256      * zeros, 0 otherwise.
 257      */
 258     int (*bdrv_has_zero_init)(BlockDriverState *bs);
 259
 260     /* Remove fd handlers, timers, and other event loop callbacks so the event
 261      * loop is no longer in use.  Called with no in-flight requests and in
 262      * depth-first traversal order with parents before child nodes.
 263      */
 264     void (*bdrv_detach_aio_context)(BlockDriverState *bs);
 265
 266     /* Add fd handlers, timers, and other event loop callbacks so I/O requests
 267      * can be processed again.  Called with no in-flight requests and in
 268      * depth-first traversal order with child nodes before parent nodes.
 269      */
 270     void (*bdrv_attach_aio_context)(BlockDriverState *bs,
 271                                     AioContext *new_context);
 272
 273     /* io queue for linux-aio */
 274     void (*bdrv_io_plug)(BlockDriverState *bs);
 275     void (*bdrv_io_unplug)(BlockDriverState *bs);
 276     void (*bdrv_flush_io_queue)(BlockDriverState *bs);
 277
 278     /**
 279      * Try to get @bs's logical and physical block size.
 280      * On success, store them in @bsz and return zero.
 281      * On failure, return negative errno.
 282      */
 283     int (*bdrv_probe_blocksizes)(BlockDriverState *bs, BlockSizes *bsz);
 284     /**
 285      * Try to get @bs's geometry (cyls, heads, sectors)
 286      * On success, store them in @geo and return 0.
 287      * On failure return -errno.
 288      * Only drivers that want to override guest geometry implement this
 289      * callback; see hd_geometry_guess().
 290      */
 291     int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo);
 292
 293     QLIST_ENTRY(BlockDriver) list;
 294 };
 295
 296 typedef struct BlockLimits {
 297     /* maximum number of sectors that can be discarded at once */
 298     int max_discard;
 299
 300     /* optimal alignment for discard requests in sectors */
 301     int64_t discard_alignment;
 302
 303     /* maximum number of sectors that can zeroized at once */
 304     int max_write_zeroes;
 305
 306     /* optimal alignment for write zeroes requests in sectors */
 307     int64_t write_zeroes_alignment;
 308
 309     /* optimal transfer length in sectors */
 310     int opt_transfer_length;
 311
 312     /* maximal transfer length in sectors */
 313     int max_transfer_length;
 314
 315     /* memory alignment so that no bounce buffer is needed */
 316     size_t opt_mem_alignment;
 317 } BlockLimits;
 318
 319 typedef struct BdrvOpBlocker BdrvOpBlocker;
 320
 321 typedef struct BdrvAioNotifier {
 322     void (*attached_aio_context)(AioContext *new_context, void *opaque);
 323     void (*detach_aio_context)(void *opaque);
 324
 325     void *opaque;
 326
 327     QLIST_ENTRY(BdrvAioNotifier) list;
 328 } BdrvAioNotifier;
 329
 330 /*
 331  * Note: the function bdrv_append() copies and swaps contents of
 332  * BlockDriverStates, so if you add new fields to this struct, please
 333  * inspect bdrv_append() to determine if the new fields need to be
 334  * copied as well.
 335  */
 336 struct BlockDriverState {
 337     int64_t total_sectors; /* if we are reading a disk image, give its
 338                               size in sectors */
 339     int read_only; /* if true, the media is read only */
 340     int open_flags; /* flags used to open the file, re-used for re-open */
 341     int encrypted; /* if true, the media is encrypted */
 342     int valid_key; /* if true, a valid encryption key has been set */
 343     int sg;        /* if true, the device is a /dev/sg* */
 344     int copy_on_read; /* if true, copy read backing sectors into image
 345                          note this is a reference count */
 346     bool probed;
 347
 348     BlockDriver *drv; /* NULL means no media */
 349     void *opaque;
 350
 351     BlockBackend *blk;          /* owning backend, if any */
 352
 353     AioContext *aio_context; /* event loop used for fd handlers, timers, etc */
 354     /* long-running tasks intended to always use the same AioContext as this
 355      * BDS may register themselves in this list to be notified of changes
 356      * regarding this BDS's context */
 357     QLIST_HEAD(, BdrvAioNotifier) aio_notifiers;
 358
 359     char filename[PATH_MAX];
 360     char backing_file[PATH_MAX]; /* if non zero, the image is a diff of
 361                                     this file image */
 362     char backing_format[16]; /* if non-zero and backing_file exists */
 363
 364     QDict *full_open_options;
 365     char exact_filename[PATH_MAX];
 366
 367     BlockDriverState *backing_hd;
 368     BlockDriverState *file;
 369
 370     NotifierList close_notifiers;
 371
 372     /* Callback before write request is processed */
 373     NotifierWithReturnList before_write_notifiers;
 374
 375     /* number of in-flight serialising requests */
 376     unsigned int serialising_in_flight;
 377
 378     /* I/O throttling */
 379     ThrottleState throttle_state;
 380     CoQueue      throttled_reqs[2];
 381     bool         io_limits_enabled;
 382
 383     /* I/O stats (display with "info blockstats"). */
 384     BlockAcctStats stats;
 385
 386     /* I/O Limits */
 387     BlockLimits bl;
 388
 389     /* Whether produces zeros when read beyond eof */
 390     bool zero_beyond_eof;
 391
 392     /* Alignment requirement for offset/length of I/O requests */
 393     unsigned int request_alignment;
 394
 395     /* the block size for which the guest device expects atomicity */
 396     int guest_block_size;
 397
 398     /* do we need to tell the quest if we have a volatile write cache? */
 399     int enable_write_cache;
 400
 401     /* NOTE: the following infos are only hints for real hardware
 402        drivers. They are not used by the block driver */
 403     BlockdevOnError on_read_error, on_write_error;
 404     bool iostatus_enabled;
 405     BlockDeviceIoStatus iostatus;
 406
 407     /* the following member gives a name to every node on the bs graph. */
 408     char node_name[32];
 409     /* element of the list of named nodes building the graph */
 410     QTAILQ_ENTRY(BlockDriverState) node_list;
 411     /* element of the list of "drives" the guest sees */
 412     QTAILQ_ENTRY(BlockDriverState) device_list;
 413     QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps;
 414     int refcnt;
 415
 416     QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
 417
 418     /* operation blockers */
 419     QLIST_HEAD(, BdrvOpBlocker) op_blockers[BLOCK_OP_TYPE_MAX];
 420
 421     /* long-running background operation */
 422     BlockJob *job;
 423
 424     QDict *options;
 425     BlockdevDetectZeroesOptions detect_zeroes;
 426
 427     /* The error object in use for blocking operations on backing_hd */
 428     Error *backing_blocker;
 429
 430     /* threshold limit for writes, in bytes. "High water mark". */
 431     uint64_t write_threshold_offset;
 432     NotifierWithReturn write_threshold_notifier;
 433 };
 434
 435
 436 /* Essential block drivers which must always be statically linked into qemu, and
 437  * which therefore can be accessed without using bdrv_find_format() */
 438 extern BlockDriver bdrv_file;
 439 extern BlockDriver bdrv_raw;
 440 extern BlockDriver bdrv_qcow2;
 441
 442
 443 int get_tmp_filename(char *filename, int size);
 444 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
 445                             const char *filename);
 446
 447 void bdrv_set_io_limits(BlockDriverState *bs,
 448                         ThrottleConfig *cfg);
 449
 450
 451 /**
 452  * bdrv_add_before_write_notifier:
 453  *
 454  * Register a callback that is invoked before write requests are processed but
 455  * after any throttling or waiting for overlapping requests.
 456  */
 457 void bdrv_add_before_write_notifier(BlockDriverState *bs,
 458                                     NotifierWithReturn *notifier);
 459
 460 /**
 461  * bdrv_detach_aio_context:
 462  *
 463  * May be called from .bdrv_detach_aio_context() to detach children from the
 464  * current #AioContext.  This is only needed by block drivers that manage their
 465  * own children.  Both ->file and ->backing_hd are automatically handled and
 466  * block drivers should not call this function on them explicitly.
 467  */
 468 void bdrv_detach_aio_context(BlockDriverState *bs);
 469
 470 /**
 471  * bdrv_attach_aio_context:
 472  *
 473  * May be called from .bdrv_attach_aio_context() to attach children to the new
 474  * #AioContext.  This is only needed by block drivers that manage their own
 475  * children.  Both ->file and ->backing_hd are automatically handled and block
 476  * drivers should not call this function on them explicitly.
 477  */
 478 void bdrv_attach_aio_context(BlockDriverState *bs,
 479                              AioContext *new_context);
 480
 481 /**
 482  * bdrv_add_aio_context_notifier:
 483  *
 484  * If a long-running job intends to be always run in the same AioContext as a
 485  * certain BDS, it may use this function to be notified of changes regarding the
 486  * association of the BDS to an AioContext.
 487  *
 488  * attached_aio_context() is called after the target BDS has been attached to a
 489  * new AioContext; detach_aio_context() is called before the target BDS is being
 490  * detached from its old AioContext.
 491  */
 492 void bdrv_add_aio_context_notifier(BlockDriverState *bs,
 493         void (*attached_aio_context)(AioContext *new_context, void *opaque),
 494         void (*detach_aio_context)(void *opaque), void *opaque);
 495
 496 /**
 497  * bdrv_remove_aio_context_notifier:
 498  *
 499  * Unsubscribe of change notifications regarding the BDS's AioContext. The
 500  * parameters given here have to be the same as those given to
 501  * bdrv_add_aio_context_notifier().
 502  */
 503 void bdrv_remove_aio_context_notifier(BlockDriverState *bs,
 504                                       void (*aio_context_attached)(AioContext *,
 505                                                                    void *),
 506                                       void (*aio_context_detached)(void *),
 507                                       void *opaque);
 508
 509 #ifdef _WIN32
 510 int is_windows_drive(const char *filename);
 511 #endif
 512
 513 /**
 514  * stream_start:
 515  * @bs: Block device to operate on.
 516  * @base: Block device that will become the new base, or %NULL to
 517  * flatten the whole backing file chain onto @bs.
 518  * @base_id: The file name that will be written to @bs as the new
 519  * backing file if the job completes.  Ignored if @base is %NULL.
 520  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
 521  * @on_error: The action to take upon error.
 522  * @cb: Completion function for the job.
 523  * @opaque: Opaque pointer value passed to @cb.
 524  * @errp: Error object.
 525  *
 526  * Start a streaming operation on @bs.  Clusters that are unallocated
 527  * in @bs, but allocated in any image between @base and @bs (both
 528  * exclusive) will be written to @bs.  At the end of a successful
 529  * streaming job, the backing file of @bs will be changed to
 530  * @base_id in the written image and to @base in the live BlockDriverState.
 531  */
 532 void stream_start(BlockDriverState *bs, BlockDriverState *base,
 533                   const char *base_id, int64_t speed, BlockdevOnError on_error,
 534                   BlockCompletionFunc *cb,
 535                   void *opaque, Error **errp);
 536
 537 /**
 538  * commit_start:
 539  * @bs: Active block device.
 540  * @top: Top block device to be committed.
 541  * @base: Block device that will be written into, and become the new top.
 542  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
 543  * @on_error: The action to take upon error.
 544  * @cb: Completion function for the job.
 545  * @opaque: Opaque pointer value passed to @cb.
 546  * @backing_file_str: String to use as the backing file in @top's overlay
 547  * @errp: Error object.
 548  *
 549  */
 550 void commit_start(BlockDriverState *bs, BlockDriverState *base,
 551                  BlockDriverState *top, int64_t speed,
 552                  BlockdevOnError on_error, BlockCompletionFunc *cb,
 553                  void *opaque, const char *backing_file_str, Error **errp);
 554 /**
 555  * commit_active_start:
 556  * @bs: Active block device to be committed.
 557  * @base: Block device that will be written into, and become the new top.
 558  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
 559  * @on_error: The action to take upon error.
 560  * @cb: Completion function for the job.
 561  * @opaque: Opaque pointer value passed to @cb.
 562  * @errp: Error object.
 563  *
 564  */
 565 void commit_active_start(BlockDriverState *bs, BlockDriverState *base,
 566                          int64_t speed,
 567                          BlockdevOnError on_error,
 568                          BlockCompletionFunc *cb,
 569                          void *opaque, Error **errp);
 570 /*
 571  * mirror_start:
 572  * @bs: Block device to operate on.
 573  * @target: Block device to write to.
 574  * @replaces: Block graph node name to replace once the mirror is done. Can
 575  *            only be used when full mirroring is selected.
 576  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
 577  * @granularity: The chosen granularity for the dirty bitmap.
 578  * @buf_size: The amount of data that can be in flight at one time.
 579  * @mode: Whether to collapse all images in the chain to the target.
 580  * @on_source_error: The action to take upon error reading from the source.
 581  * @on_target_error: The action to take upon error writing to the target.
 582  * @cb: Completion function for the job.
 583  * @opaque: Opaque pointer value passed to @cb.
 584  * @errp: Error object.
 585  *
 586  * Start a mirroring operation on @bs.  Clusters that are allocated
 587  * in @bs will be written to @bs until the job is cancelled or
 588  * manually completed.  At the end of a successful mirroring job,
 589  * @bs will be switched to read from @target.
 590  */
 591 void mirror_start(BlockDriverState *bs, BlockDriverState *target,
 592                   const char *replaces,
 593                   int64_t speed, int64_t granularity, int64_t buf_size,
 594                   MirrorSyncMode mode, BlockdevOnError on_source_error,
 595                   BlockdevOnError on_target_error,
 596                   BlockCompletionFunc *cb,
 597                   void *opaque, Error **errp);
 598
 599 /*
 600  * backup_start:
 601  * @bs: Block device to operate on.
 602  * @target: Block device to write to.
 603  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
 604  * @sync_mode: What parts of the disk image should be copied to the destination.
 605  * @on_source_error: The action to take upon error reading from the source.
 606  * @on_target_error: The action to take upon error writing to the target.
 607  * @cb: Completion function for the job.
 608  * @opaque: Opaque pointer value passed to @cb.
 609  *
 610  * Start a backup operation on @bs.  Clusters in @bs are written to @target
 611  * until the job is cancelled or manually completed.
 612  */
 613 void backup_start(BlockDriverState *bs, BlockDriverState *target,
 614                   int64_t speed, MirrorSyncMode sync_mode,
 615                   BlockdevOnError on_source_error,
 616                   BlockdevOnError on_target_error,
 617                   BlockCompletionFunc *cb, void *opaque,
 618                   Error **errp);
 619
 620 void blk_dev_change_media_cb(BlockBackend *blk, bool load);
 621 bool blk_dev_has_removable_media(BlockBackend *blk);
 622 void blk_dev_eject_request(BlockBackend *blk, bool force);
 623 bool blk_dev_is_tray_open(BlockBackend *blk);
 624 bool blk_dev_is_medium_locked(BlockBackend *blk);
 625 void blk_dev_resize_cb(BlockBackend *blk);
 626
 627 #endif /* BLOCK_INT_H */