include/block/block.h

   1 #ifndef BLOCK_H
   2 #define BLOCK_H
   3
   4 #include "block/aio.h"
   5 #include "qemu-common.h"
   6 #include "qemu/option.h"
   7 #include "qemu/coroutine.h"
   8 #include "block/accounting.h"
   9 #include "qapi/qmp/qobject.h"
  10 #include "qapi-types.h"
  11
  12 /* block.c */
  13 typedef struct BlockDriver BlockDriver;
  14 typedef struct BlockJob BlockJob;
  15 typedef struct BdrvChild BdrvChild;
  16 typedef struct BdrvChildRole BdrvChildRole;
  17 typedef struct BlockJobTxn BlockJobTxn;
  18
  19 typedef struct BlockDriverInfo {
  20     /* in bytes, 0 if irrelevant */
  21     int cluster_size;
  22     /* offset at which the VM state can be saved (0 if not possible) */
  23     int64_t vm_state_offset;
  24     bool is_dirty;
  25     /*
  26      * True if unallocated blocks read back as zeroes. This is equivalent
  27      * to the LBPRZ flag in the SCSI logical block provisioning page.
  28      */
  29     bool unallocated_blocks_are_zero;
  30     /*
  31      * True if the driver can optimize writing zeroes by unmapping
  32      * sectors. This is equivalent to the BLKDISCARDZEROES ioctl in Linux
  33      * with the difference that in qemu a discard is allowed to silently
  34      * fail. Therefore we have to use bdrv_write_zeroes with the
  35      * BDRV_REQ_MAY_UNMAP flag for an optimized zero write with unmapping.
  36      * After this call the driver has to guarantee that the contents read
  37      * back as zero. It is additionally required that the block device is
  38      * opened with BDRV_O_UNMAP flag for this to work.
  39      */
  40     bool can_write_zeroes_with_unmap;
  41     /*
  42      * True if this block driver only supports compressed writes
  43      */
  44     bool needs_compressed_writes;
  45 } BlockDriverInfo;
  46
  47 typedef struct BlockFragInfo {
  48     uint64_t allocated_clusters;
  49     uint64_t total_clusters;
  50     uint64_t fragmented_clusters;
  51     uint64_t compressed_clusters;
  52 } BlockFragInfo;
  53
  54 typedef enum {
  55     BDRV_REQ_COPY_ON_READ       = 0x1,
  56     BDRV_REQ_ZERO_WRITE         = 0x2,
  57     /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver
  58      * is allowed to optimize a write zeroes request by unmapping (discarding)
  59      * blocks if it is guaranteed that the result will read back as
  60      * zeroes. The flag is only passed to the driver if the block device is
  61      * opened with BDRV_O_UNMAP.
  62      */
  63     BDRV_REQ_MAY_UNMAP          = 0x4,
  64     BDRV_REQ_NO_SERIALISING     = 0x8,
  65 } BdrvRequestFlags;
  66
  67 typedef struct BlockSizes {
  68     uint32_t phys;
  69     uint32_t log;
  70 } BlockSizes;
  71
  72 typedef struct HDGeometry {
  73     uint32_t heads;
  74     uint32_t sectors;
  75     uint32_t cylinders;
  76 } HDGeometry;
  77
  78 #define BDRV_O_RDWR        0x0002
  79 #define BDRV_O_SNAPSHOT    0x0008 /* open the file read only and save writes in a snapshot */
  80 #define BDRV_O_TEMPORARY   0x0010 /* delete the file after use */
  81 #define BDRV_O_NOCACHE     0x0020 /* do not use the host page cache */
  82 #define BDRV_O_CACHE_WB    0x0040 /* use write-back caching */
  83 #define BDRV_O_NATIVE_AIO  0x0080 /* use native AIO instead of the thread pool */
  84 #define BDRV_O_NO_BACKING  0x0100 /* don't open the backing file */
  85 #define BDRV_O_NO_FLUSH    0x0200 /* disable flushing on this disk */
  86 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
  87 #define BDRV_O_INCOMING    0x0800  /* consistency hint for incoming migration */
  88 #define BDRV_O_CHECK       0x1000  /* open solely for consistency check */
  89 #define BDRV_O_ALLOW_RDWR  0x2000  /* allow reopen to change from r/o to r/w */
  90 #define BDRV_O_UNMAP       0x4000  /* execute guest UNMAP/TRIM operations */
  91 #define BDRV_O_PROTOCOL    0x8000  /* if no block driver is explicitly given:
  92                                       select an appropriate protocol driver,
  93                                       ignoring the format layer */
  94
  95 #define BDRV_O_CACHE_MASK  (BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH)
  96
  97
  98 /* Option names of options parsed by the block layer */
  99
 100 #define BDRV_OPT_CACHE_WB       "cache.writeback"
 101 #define BDRV_OPT_CACHE_DIRECT   "cache.direct"
 102 #define BDRV_OPT_CACHE_NO_FLUSH "cache.no-flush"
 103
 104
 105 #define BDRV_SECTOR_BITS   9
 106 #define BDRV_SECTOR_SIZE   (1ULL << BDRV_SECTOR_BITS)
 107 #define BDRV_SECTOR_MASK   ~(BDRV_SECTOR_SIZE - 1)
 108
 109 #define BDRV_REQUEST_MAX_SECTORS MIN(SIZE_MAX >> BDRV_SECTOR_BITS, \
 110                                      INT_MAX >> BDRV_SECTOR_BITS)
 111
 112 /*
 113  * Allocation status flags
 114  * BDRV_BLOCK_DATA: data is read from bs->file or another file
 115  * BDRV_BLOCK_ZERO: sectors read as zero
 116  * BDRV_BLOCK_OFFSET_VALID: sector stored in bs->file as raw data
 117  * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
 118  *                       layer (as opposed to the backing file)
 119  * BDRV_BLOCK_RAW: used internally to indicate that the request
 120  *                 was answered by the raw driver and that one
 121  *                 should look in bs->file directly.
 122  *
 123  * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 represent the offset in
 124  * bs->file where sector data can be read from as raw data.
 125  *
 126  * DATA == 0 && ZERO == 0 means that data is read from backing_hd if present.
 127  *
 128  * DATA ZERO OFFSET_VALID
 129  *  t    t        t       sectors read as zero, bs->file is zero at offset
 130  *  t    f        t       sectors read as valid from bs->file at offset
 131  *  f    t        t       sectors preallocated, read as zero, bs->file not
 132  *                        necessarily zero at offset
 133  *  f    f        t       sectors preallocated but read from backing_hd,
 134  *                        bs->file contains garbage at offset
 135  *  t    t        f       sectors preallocated, read as zero, unknown offset
 136  *  t    f        f       sectors read from unknown file or offset
 137  *  f    t        f       not allocated or unknown offset, read as zero
 138  *  f    f        f       not allocated or unknown offset, read from backing_hd
 139  */
 140 #define BDRV_BLOCK_DATA         0x01
 141 #define BDRV_BLOCK_ZERO         0x02
 142 #define BDRV_BLOCK_OFFSET_VALID 0x04
 143 #define BDRV_BLOCK_RAW          0x08
 144 #define BDRV_BLOCK_ALLOCATED    0x10
 145 #define BDRV_BLOCK_OFFSET_MASK  BDRV_SECTOR_MASK
 146
 147 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue;
 148
 149 typedef struct BDRVReopenState {
 150     BlockDriverState *bs;
 151     int flags;
 152     QDict *options;
 153     void *opaque;
 154 } BDRVReopenState;
 155
 156 /*
 157  * Block operation types
 158  */
 159 typedef enum BlockOpType {
 160     BLOCK_OP_TYPE_BACKUP_SOURCE,
 161     BLOCK_OP_TYPE_BACKUP_TARGET,
 162     BLOCK_OP_TYPE_CHANGE,
 163     BLOCK_OP_TYPE_COMMIT_SOURCE,
 164     BLOCK_OP_TYPE_COMMIT_TARGET,
 165     BLOCK_OP_TYPE_DATAPLANE,
 166     BLOCK_OP_TYPE_DRIVE_DEL,
 167     BLOCK_OP_TYPE_EJECT,
 168     BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
 169     BLOCK_OP_TYPE_INTERNAL_SNAPSHOT,
 170     BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE,
 171     BLOCK_OP_TYPE_MIRROR,
 172     BLOCK_OP_TYPE_RESIZE,
 173     BLOCK_OP_TYPE_STREAM,
 174     BLOCK_OP_TYPE_REPLACE,
 175     BLOCK_OP_TYPE_MAX,
 176 } BlockOpType;
 177
 178 void bdrv_info_print(Monitor *mon, const QObject *data);
 179 void bdrv_info(Monitor *mon, QObject **ret_data);
 180 void bdrv_stats_print(Monitor *mon, const QObject *data);
 181 void bdrv_info_stats(Monitor *mon, QObject **ret_data);
 182
 183 /* disk I/O throttling */
 184 void bdrv_io_limits_enable(BlockDriverState *bs, const char *group);
 185 void bdrv_io_limits_disable(BlockDriverState *bs);
 186 void bdrv_io_limits_update_group(BlockDriverState *bs, const char *group);
 187
 188 void bdrv_init(void);
 189 void bdrv_init_with_whitelist(void);
 190 BlockDriver *bdrv_find_protocol(const char *filename,
 191                                 bool allow_protocol_prefix,
 192                                 Error **errp);
 193 BlockDriver *bdrv_find_format(const char *format_name);
 194 int bdrv_create(BlockDriver *drv, const char* filename,
 195                 QemuOpts *opts, Error **errp);
 196 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp);
 197 BlockDriverState *bdrv_new_root(void);
 198 BlockDriverState *bdrv_new(void);
 199 void bdrv_make_anon(BlockDriverState *bs);
 200 void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old);
 201 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top);
 202 void bdrv_replace_in_backing_chain(BlockDriverState *old,
 203                                    BlockDriverState *new);
 204
 205 int bdrv_parse_cache_flags(const char *mode, int *flags);
 206 int bdrv_parse_discard_flags(const char *mode, int *flags);
 207 BdrvChild *bdrv_open_child(const char *filename,
 208                            QDict *options, const char *bdref_key,
 209                            BlockDriverState* parent,
 210                            const BdrvChildRole *child_role,
 211                            bool allow_none, Error **errp);
 212 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd);
 213 int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp);
 214 int bdrv_append_temp_snapshot(BlockDriverState *bs, int flags, Error **errp);
 215 int bdrv_open(BlockDriverState **pbs, const char *filename,
 216               const char *reference, QDict *options, int flags, Error **errp);
 217 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
 218                                     BlockDriverState *bs,
 219                                     QDict *options, int flags);
 220 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp);
 221 int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp);
 222 int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
 223                         BlockReopenQueue *queue, Error **errp);
 224 void bdrv_reopen_commit(BDRVReopenState *reopen_state);
 225 void bdrv_reopen_abort(BDRVReopenState *reopen_state);
 226 void bdrv_close(BlockDriverState *bs);
 227 void bdrv_add_close_notifier(BlockDriverState *bs, Notifier *notify);
 228 int bdrv_read(BlockDriverState *bs, int64_t sector_num,
 229               uint8_t *buf, int nb_sectors);
 230 int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
 231                           uint8_t *buf, int nb_sectors);
 232 int bdrv_write(BlockDriverState *bs, int64_t sector_num,
 233                const uint8_t *buf, int nb_sectors);
 234 int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num,
 235                int nb_sectors, BdrvRequestFlags flags);
 236 BlockAIOCB *bdrv_aio_write_zeroes(BlockDriverState *bs, int64_t sector_num,
 237                                   int nb_sectors, BdrvRequestFlags flags,
 238                                   BlockCompletionFunc *cb, void *opaque);
 239 int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags);
 240 int bdrv_pread(BlockDriverState *bs, int64_t offset,
 241                void *buf, int count);
 242 int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
 243                 const void *buf, int count);
 244 int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov);
 245 int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
 246     const void *buf, int count);
 247 int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num,
 248     int nb_sectors, QEMUIOVector *qiov);
 249 int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
 250     int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
 251 int coroutine_fn bdrv_co_readv_no_serialising(BlockDriverState *bs,
 252     int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
 253 int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,
 254     int nb_sectors, QEMUIOVector *qiov);
 255 /*
 256  * Efficiently zero a region of the disk image.  Note that this is a regular
 257  * I/O request like read or write and should have a reasonable size.  This
 258  * function is not suitable for zeroing the entire image in a single request
 259  * because it may allocate memory for the entire region.
 260  */
 261 int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
 262     int nb_sectors, BdrvRequestFlags flags);
 263 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
 264     const char *backing_file);
 265 int bdrv_get_backing_file_depth(BlockDriverState *bs);
 266 void bdrv_refresh_filename(BlockDriverState *bs);
 267 int bdrv_truncate(BlockDriverState *bs, int64_t offset);
 268 int64_t bdrv_nb_sectors(BlockDriverState *bs);
 269 int64_t bdrv_getlength(BlockDriverState *bs);
 270 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs);
 271 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
 272 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp);
 273 int bdrv_commit(BlockDriverState *bs);
 274 int bdrv_commit_all(void);
 275 int bdrv_change_backing_file(BlockDriverState *bs,
 276     const char *backing_file, const char *backing_fmt);
 277 void bdrv_register(BlockDriver *bdrv);
 278 int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
 279                            BlockDriverState *base,
 280                            const char *backing_file_str);
 281 BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
 282                                     BlockDriverState *bs);
 283 BlockDriverState *bdrv_find_base(BlockDriverState *bs);
 284
 285
 286 typedef struct BdrvCheckResult {
 287     int corruptions;
 288     int leaks;
 289     int check_errors;
 290     int corruptions_fixed;
 291     int leaks_fixed;
 292     int64_t image_end_offset;
 293     BlockFragInfo bfi;
 294 } BdrvCheckResult;
 295
 296 typedef enum {
 297     BDRV_FIX_LEAKS    = 1,
 298     BDRV_FIX_ERRORS   = 2,
 299 } BdrvCheckMode;
 300
 301 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
 302
 303 /* The units of offset and total_work_size may be chosen arbitrarily by the
 304  * block driver; total_work_size may change during the course of the amendment
 305  * operation */
 306 typedef void BlockDriverAmendStatusCB(BlockDriverState *bs, int64_t offset,
 307                                       int64_t total_work_size);
 308 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts,
 309                        BlockDriverAmendStatusCB *status_cb);
 310
 311 /* external snapshots */
 312 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,
 313                                       BlockDriverState *candidate);
 314 bool bdrv_is_first_non_filter(BlockDriverState *candidate);
 315
 316 /* check if a named node can be replaced when doing drive-mirror */
 317 BlockDriverState *check_to_replace_node(BlockDriverState *parent_bs,
 318                                         const char *node_name, Error **errp);
 319
 320 /* async block I/O */
 321 typedef void BlockDriverDirtyHandler(BlockDriverState *bs, int64_t sector,
 322                                      int sector_num);
 323 BlockAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
 324                            QEMUIOVector *iov, int nb_sectors,
 325                            BlockCompletionFunc *cb, void *opaque);
 326 BlockAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
 327                             QEMUIOVector *iov, int nb_sectors,
 328                             BlockCompletionFunc *cb, void *opaque);
 329 BlockAIOCB *bdrv_aio_flush(BlockDriverState *bs,
 330                            BlockCompletionFunc *cb, void *opaque);
 331 BlockAIOCB *bdrv_aio_discard(BlockDriverState *bs,
 332                              int64_t sector_num, int nb_sectors,
 333                              BlockCompletionFunc *cb, void *opaque);
 334 void bdrv_aio_cancel(BlockAIOCB *acb);
 335 void bdrv_aio_cancel_async(BlockAIOCB *acb);
 336
 337 typedef struct BlockRequest {
 338     /* Fields to be filled by multiwrite caller */
 339     union {
 340         struct {
 341             int64_t sector;
 342             int nb_sectors;
 343             int flags;
 344             QEMUIOVector *qiov;
 345         };
 346         struct {
 347             int req;
 348             void *buf;
 349         };
 350     };
 351     BlockCompletionFunc *cb;
 352     void *opaque;
 353
 354     /* Filled by multiwrite implementation */
 355     int error;
 356 } BlockRequest;
 357
 358 int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs,
 359     int num_reqs);
 360
 361 /* sg packet commands */
 362 int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf);
 363 BlockAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
 364         unsigned long int req, void *buf,
 365         BlockCompletionFunc *cb, void *opaque);
 366
 367 /* Invalidate any cached metadata used by image formats */
 368 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
 369 void bdrv_invalidate_cache_all(Error **errp);
 370
 371 /* Ensure contents are flushed to disk.  */
 372 int bdrv_flush(BlockDriverState *bs);
 373 int coroutine_fn bdrv_co_flush(BlockDriverState *bs);
 374 int bdrv_flush_all(void);
 375 void bdrv_close_all(void);
 376 void bdrv_drain(BlockDriverState *bs);
 377 void bdrv_drain_all(void);
 378
 379 int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
 380 int bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
 381 int bdrv_has_zero_init_1(BlockDriverState *bs);
 382 int bdrv_has_zero_init(BlockDriverState *bs);
 383 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs);
 384 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs);
 385 int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num,
 386                               int nb_sectors, int *pnum);
 387 int64_t bdrv_get_block_status_above(BlockDriverState *bs,
 388                                     BlockDriverState *base,
 389                                     int64_t sector_num,
 390                                     int nb_sectors, int *pnum);
 391 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
 392                       int *pnum);
 393 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,
 394                             int64_t sector_num, int nb_sectors, int *pnum);
 395
 396 int bdrv_is_read_only(BlockDriverState *bs);
 397 int bdrv_is_sg(BlockDriverState *bs);
 398 int bdrv_enable_write_cache(BlockDriverState *bs);
 399 void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce);
 400 bool bdrv_is_inserted(BlockDriverState *bs);
 401 int bdrv_media_changed(BlockDriverState *bs);
 402 void bdrv_lock_medium(BlockDriverState *bs, bool locked);
 403 void bdrv_eject(BlockDriverState *bs, bool eject_flag);
 404 const char *bdrv_get_format_name(BlockDriverState *bs);
 405 BlockDriverState *bdrv_find_node(const char *node_name);
 406 BlockDeviceInfoList *bdrv_named_nodes_list(Error **errp);
 407 BlockDriverState *bdrv_lookup_bs(const char *device,
 408                                  const char *node_name,
 409                                  Error **errp);
 410 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base);
 411 BlockDriverState *bdrv_next_node(BlockDriverState *bs);
 412 BlockDriverState *bdrv_next(BlockDriverState *bs);
 413 int bdrv_is_encrypted(BlockDriverState *bs);
 414 int bdrv_key_required(BlockDriverState *bs);
 415 int bdrv_set_key(BlockDriverState *bs, const char *key);
 416 void bdrv_add_key(BlockDriverState *bs, const char *key, Error **errp);
 417 int bdrv_query_missing_keys(void);
 418 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
 419                          void *opaque);
 420 const char *bdrv_get_node_name(const BlockDriverState *bs);
 421 const char *bdrv_get_device_name(const BlockDriverState *bs);
 422 const char *bdrv_get_device_or_node_name(const BlockDriverState *bs);
 423 int bdrv_get_flags(BlockDriverState *bs);
 424 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
 425                           const uint8_t *buf, int nb_sectors);
 426 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi);
 427 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs);
 428 void bdrv_round_to_clusters(BlockDriverState *bs,
 429                             int64_t sector_num, int nb_sectors,
 430                             int64_t *cluster_sector_num,
 431                             int *cluster_nb_sectors);
 432
 433 const char *bdrv_get_encrypted_filename(BlockDriverState *bs);
 434 void bdrv_get_backing_filename(BlockDriverState *bs,
 435                                char *filename, int filename_size);
 436 void bdrv_get_full_backing_filename(BlockDriverState *bs,
 437                                     char *dest, size_t sz, Error **errp);
 438 void bdrv_get_full_backing_filename_from_filename(const char *backed,
 439                                                   const char *backing,
 440                                                   char *dest, size_t sz,
 441                                                   Error **errp);
 442 int bdrv_is_snapshot(BlockDriverState *bs);
 443
 444 int path_has_protocol(const char *path);
 445 int path_is_absolute(const char *path);
 446 void path_combine(char *dest, int dest_size,
 447                   const char *base_path,
 448                   const char *filename);
 449
 450 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
 451 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
 452                       int64_t pos, int size);
 453
 454 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
 455                       int64_t pos, int size);
 456
 457 void bdrv_img_create(const char *filename, const char *fmt,
 458                      const char *base_filename, const char *base_fmt,
 459                      char *options, uint64_t img_size, int flags,
 460                      Error **errp, bool quiet);
 461
 462 /* Returns the alignment in bytes that is required so that no bounce buffer
 463  * is required throughout the stack */
 464 size_t bdrv_min_mem_align(BlockDriverState *bs);
 465 /* Returns optimal alignment in bytes for bounce buffer */
 466 size_t bdrv_opt_mem_align(BlockDriverState *bs);
 467 void *qemu_blockalign(BlockDriverState *bs, size_t size);
 468 void *qemu_blockalign0(BlockDriverState *bs, size_t size);
 469 void *qemu_try_blockalign(BlockDriverState *bs, size_t size);
 470 void *qemu_try_blockalign0(BlockDriverState *bs, size_t size);
 471 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);
 472
 473 struct HBitmapIter;
 474 typedef struct BdrvDirtyBitmap BdrvDirtyBitmap;
 475 BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
 476                                           uint32_t granularity,
 477                                           const char *name,
 478                                           Error **errp);
 479 int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs,
 480                                        BdrvDirtyBitmap *bitmap,
 481                                        Error **errp);
 482 BdrvDirtyBitmap *bdrv_dirty_bitmap_abdicate(BlockDriverState *bs,
 483                                             BdrvDirtyBitmap *bitmap,
 484                                             Error **errp);
 485 BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
 486                                            BdrvDirtyBitmap *bitmap,
 487                                            Error **errp);
 488 BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs,
 489                                         const char *name);
 490 void bdrv_dirty_bitmap_make_anon(BdrvDirtyBitmap *bitmap);
 491 void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
 492 void bdrv_disable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
 493 void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
 494 BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
 495 uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
 496 uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap);
 497 bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
 498 bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap);
 499 DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap);
 500 int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
 501 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
 502                            int64_t cur_sector, int nr_sectors);
 503 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
 504                              int64_t cur_sector, int nr_sectors);
 505 void bdrv_dirty_iter_init(BdrvDirtyBitmap *bitmap, struct HBitmapIter *hbi);
 506 void bdrv_set_dirty_iter(struct HBitmapIter *hbi, int64_t offset);
 507 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap);
 508
 509 void bdrv_enable_copy_on_read(BlockDriverState *bs);
 510 void bdrv_disable_copy_on_read(BlockDriverState *bs);
 511
 512 void bdrv_ref(BlockDriverState *bs);
 513 void bdrv_unref(BlockDriverState *bs);
 514 void bdrv_unref_child(BlockDriverState *parent, BdrvChild *child);
 515
 516 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
 517 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
 518 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason);
 519 void bdrv_op_block_all(BlockDriverState *bs, Error *reason);
 520 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason);
 521 bool bdrv_op_blocker_is_empty(BlockDriverState *bs);
 522
 523 #define BLKDBG_EVENT(child, evt) \
 524     do { \
 525         if (child) { \
 526             bdrv_debug_event(child->bs, evt); \
 527         } \
 528     } while (0)
 529
 530 void bdrv_debug_event(BlockDriverState *bs, BlkdebugEvent event);
 531
 532 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
 533                            const char *tag);
 534 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag);
 535 int bdrv_debug_resume(BlockDriverState *bs, const char *tag);
 536 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag);
 537
 538 /**
 539  * bdrv_get_aio_context:
 540  *
 541  * Returns: the currently bound #AioContext
 542  */
 543 AioContext *bdrv_get_aio_context(BlockDriverState *bs);
 544
 545 /**
 546  * bdrv_set_aio_context:
 547  *
 548  * Changes the #AioContext used for fd handlers, timers, and BHs by this
 549  * BlockDriverState and all its children.
 550  *
 551  * This function must be called with iothread lock held.
 552  */
 553 void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context);
 554 int bdrv_probe_blocksizes(BlockDriverState *bs, BlockSizes *bsz);
 555 int bdrv_probe_geometry(BlockDriverState *bs, HDGeometry *geo);
 556
 557 void bdrv_io_plug(BlockDriverState *bs);
 558 void bdrv_io_unplug(BlockDriverState *bs);
 559 void bdrv_flush_io_queue(BlockDriverState *bs);
 560
 561 /**
 562  * bdrv_drained_begin:
 563  *
 564  * Begin a quiesced section for exclusive access to the BDS, by disabling
 565  * external request sources including NBD server and device model. Note that
 566  * this doesn't block timers or coroutines from submitting more requests, which
 567  * means block_job_pause is still necessary.
 568  *
 569  * This function can be recursive.
 570  */
 571 void bdrv_drained_begin(BlockDriverState *bs);
 572
 573 /**
 574  * bdrv_drained_end:
 575  *
 576  * End a quiescent section started by bdrv_drained_begin().
 577  */
 578 void bdrv_drained_end(BlockDriverState *bs);
 579
 580 #endif