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 "block/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
  16 typedef struct BlockDriverInfo {
  17     /* in bytes, 0 if irrelevant */
  18     int cluster_size;
  19     /* offset at which the VM state can be saved (0 if not possible) */
  20     int64_t vm_state_offset;
  21     bool is_dirty;
  22     /*
  23      * True if unallocated blocks read back as zeroes. This is equivalent
  24      * to the the LBPRZ flag in the SCSI logical block provisioning page.
  25      */
  26     bool unallocated_blocks_are_zero;
  27     /*
  28      * True if the driver can optimize writing zeroes by unmapping
  29      * sectors. This is equivalent to the BLKDISCARDZEROES ioctl in Linux
  30      * with the difference that in qemu a discard is allowed to silently
  31      * fail. Therefore we have to use bdrv_write_zeroes with the
  32      * BDRV_REQ_MAY_UNMAP flag for an optimized zero write with unmapping.
  33      * After this call the driver has to guarantee that the contents read
  34      * back as zero. It is additionally required that the block device is
  35      * opened with BDRV_O_UNMAP flag for this to work.
  36      */
  37     bool can_write_zeroes_with_unmap;
  38     /*
  39      * True if this block driver only supports compressed writes
  40      */
  41     bool needs_compressed_writes;
  42 } BlockDriverInfo;
  43
  44 typedef struct BlockFragInfo {
  45     uint64_t allocated_clusters;
  46     uint64_t total_clusters;
  47     uint64_t fragmented_clusters;
  48     uint64_t compressed_clusters;
  49 } BlockFragInfo;
  50
  51 /* Callbacks for block device models */
  52 typedef struct BlockDevOps {
  53     /*
  54      * Runs when virtual media changed (monitor commands eject, change)
  55      * Argument load is true on load and false on eject.
  56      * Beware: doesn't run when a host device's physical media
  57      * changes.  Sure would be useful if it did.
  58      * Device models with removable media must implement this callback.
  59      */
  60     void (*change_media_cb)(void *opaque, bool load);
  61     /*
  62      * Runs when an eject request is issued from the monitor, the tray
  63      * is closed, and the medium is locked.
  64      * Device models that do not implement is_medium_locked will not need
  65      * this callback.  Device models that can lock the medium or tray might
  66      * want to implement the callback and unlock the tray when "force" is
  67      * true, even if they do not support eject requests.
  68      */
  69     void (*eject_request_cb)(void *opaque, bool force);
  70     /*
  71      * Is the virtual tray open?
  72      * Device models implement this only when the device has a tray.
  73      */
  74     bool (*is_tray_open)(void *opaque);
  75     /*
  76      * Is the virtual medium locked into the device?
  77      * Device models implement this only when device has such a lock.
  78      */
  79     bool (*is_medium_locked)(void *opaque);
  80     /*
  81      * Runs when the size changed (e.g. monitor command block_resize)
  82      */
  83     void (*resize_cb)(void *opaque);
  84 } BlockDevOps;
  85
  86 typedef enum {
  87     BDRV_REQ_COPY_ON_READ = 0x1,
  88     BDRV_REQ_ZERO_WRITE   = 0x2,
  89     /* The BDRV_REQ_MAY_UNMAP flag is used to indicate that the block driver
  90      * is allowed to optimize a write zeroes request by unmapping (discarding)
  91      * blocks if it is guaranteed that the result will read back as
  92      * zeroes. The flag is only passed to the driver if the block device is
  93      * opened with BDRV_O_UNMAP.
  94      */
  95     BDRV_REQ_MAY_UNMAP    = 0x4,
  96 } BdrvRequestFlags;
  97
  98 #define BDRV_O_RDWR        0x0002
  99 #define BDRV_O_SNAPSHOT    0x0008 /* open the file read only and save writes in a snapshot */
 100 #define BDRV_O_TEMPORARY   0x0010 /* delete the file after use */
 101 #define BDRV_O_NOCACHE     0x0020 /* do not use the host page cache */
 102 #define BDRV_O_CACHE_WB    0x0040 /* use write-back caching */
 103 #define BDRV_O_NATIVE_AIO  0x0080 /* use native AIO instead of the thread pool */
 104 #define BDRV_O_NO_BACKING  0x0100 /* don't open the backing file */
 105 #define BDRV_O_NO_FLUSH    0x0200 /* disable flushing on this disk */
 106 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
 107 #define BDRV_O_INCOMING    0x0800  /* consistency hint for incoming migration */
 108 #define BDRV_O_CHECK       0x1000  /* open solely for consistency check */
 109 #define BDRV_O_ALLOW_RDWR  0x2000  /* allow reopen to change from r/o to r/w */
 110 #define BDRV_O_UNMAP       0x4000  /* execute guest UNMAP/TRIM operations */
 111 #define BDRV_O_PROTOCOL    0x8000  /* if no block driver is explicitly given:
 112                                       select an appropriate protocol driver,
 113                                       ignoring the format layer */
 114
 115 #define BDRV_O_CACHE_MASK  (BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH)
 116
 117 #define BDRV_SECTOR_BITS   9
 118 #define BDRV_SECTOR_SIZE   (1ULL << BDRV_SECTOR_BITS)
 119 #define BDRV_SECTOR_MASK   ~(BDRV_SECTOR_SIZE - 1)
 120
 121 /* BDRV_BLOCK_DATA: data is read from bs->file or another file
 122  * BDRV_BLOCK_ZERO: sectors read as zero
 123  * BDRV_BLOCK_OFFSET_VALID: sector stored in bs->file as raw data
 124  * BDRV_BLOCK_ALLOCATED: the content of the block is determined by this
 125  *                       layer (as opposed to the backing file)
 126  * BDRV_BLOCK_RAW: used internally to indicate that the request
 127  *                 was answered by the raw driver and that one
 128  *                 should look in bs->file directly.
 129  *
 130  * If BDRV_BLOCK_OFFSET_VALID is set, bits 9-62 represent the offset in
 131  * bs->file where sector data can be read from as raw data.
 132  *
 133  * DATA == 0 && ZERO == 0 means that data is read from backing_hd if present.
 134  *
 135  * DATA ZERO OFFSET_VALID
 136  *  t    t        t       sectors read as zero, bs->file is zero at offset
 137  *  t    f        t       sectors read as valid from bs->file at offset
 138  *  f    t        t       sectors preallocated, read as zero, bs->file not
 139  *                        necessarily zero at offset
 140  *  f    f        t       sectors preallocated but read from backing_hd,
 141  *                        bs->file contains garbage at offset
 142  *  t    t        f       sectors preallocated, read as zero, unknown offset
 143  *  t    f        f       sectors read from unknown file or offset
 144  *  f    t        f       not allocated or unknown offset, read as zero
 145  *  f    f        f       not allocated or unknown offset, read from backing_hd
 146  */
 147 #define BDRV_BLOCK_DATA         0x01
 148 #define BDRV_BLOCK_ZERO         0x02
 149 #define BDRV_BLOCK_OFFSET_VALID 0x04
 150 #define BDRV_BLOCK_RAW          0x08
 151 #define BDRV_BLOCK_ALLOCATED    0x10
 152 #define BDRV_BLOCK_OFFSET_MASK  BDRV_SECTOR_MASK
 153
 154 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue;
 155
 156 typedef struct BDRVReopenState {
 157     BlockDriverState *bs;
 158     int flags;
 159     void *opaque;
 160 } BDRVReopenState;
 161
 162 /*
 163  * Block operation types
 164  */
 165 typedef enum BlockOpType {
 166     BLOCK_OP_TYPE_BACKUP_SOURCE,
 167     BLOCK_OP_TYPE_BACKUP_TARGET,
 168     BLOCK_OP_TYPE_CHANGE,
 169     BLOCK_OP_TYPE_COMMIT,
 170     BLOCK_OP_TYPE_DATAPLANE,
 171     BLOCK_OP_TYPE_DRIVE_DEL,
 172     BLOCK_OP_TYPE_EJECT,
 173     BLOCK_OP_TYPE_EXTERNAL_SNAPSHOT,
 174     BLOCK_OP_TYPE_INTERNAL_SNAPSHOT,
 175     BLOCK_OP_TYPE_INTERNAL_SNAPSHOT_DELETE,
 176     BLOCK_OP_TYPE_MIRROR,
 177     BLOCK_OP_TYPE_RESIZE,
 178     BLOCK_OP_TYPE_STREAM,
 179     BLOCK_OP_TYPE_REPLACE,
 180     BLOCK_OP_TYPE_MAX,
 181 } BlockOpType;
 182
 183 void bdrv_iostatus_enable(BlockDriverState *bs);
 184 void bdrv_iostatus_reset(BlockDriverState *bs);
 185 void bdrv_iostatus_disable(BlockDriverState *bs);
 186 bool bdrv_iostatus_is_enabled(const BlockDriverState *bs);
 187 void bdrv_iostatus_set_err(BlockDriverState *bs, int error);
 188 void bdrv_info_print(Monitor *mon, const QObject *data);
 189 void bdrv_info(Monitor *mon, QObject **ret_data);
 190 void bdrv_stats_print(Monitor *mon, const QObject *data);
 191 void bdrv_info_stats(Monitor *mon, QObject **ret_data);
 192
 193 /* disk I/O throttling */
 194 void bdrv_io_limits_enable(BlockDriverState *bs);
 195 void bdrv_io_limits_disable(BlockDriverState *bs);
 196
 197 void bdrv_init(void);
 198 void bdrv_init_with_whitelist(void);
 199 BlockDriver *bdrv_find_protocol(const char *filename,
 200                                 bool allow_protocol_prefix);
 201 BlockDriver *bdrv_find_format(const char *format_name);
 202 BlockDriver *bdrv_find_whitelisted_format(const char *format_name,
 203                                           bool readonly);
 204 int bdrv_create(BlockDriver *drv, const char* filename,
 205                 QemuOpts *opts, Error **errp);
 206 int bdrv_create_file(const char *filename, QemuOpts *opts, Error **errp);
 207 BlockDriverState *bdrv_new(const char *device_name, Error **errp);
 208 void bdrv_make_anon(BlockDriverState *bs);
 209 void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old);
 210 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top);
 211 int bdrv_parse_cache_flags(const char *mode, int *flags);
 212 int bdrv_parse_discard_flags(const char *mode, int *flags);
 213 int bdrv_open_image(BlockDriverState **pbs, const char *filename,
 214                     QDict *options, const char *bdref_key, int flags,
 215                     bool allow_none, Error **errp);
 216 void bdrv_set_backing_hd(BlockDriverState *bs, BlockDriverState *backing_hd);
 217 int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp);
 218 int bdrv_append_temp_snapshot(BlockDriverState *bs, int flags, Error **errp);
 219 int bdrv_open(BlockDriverState **pbs, const char *filename,
 220               const char *reference, QDict *options, int flags,
 221               BlockDriver *drv, Error **errp);
 222 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
 223                                     BlockDriverState *bs, int flags);
 224 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp);
 225 int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp);
 226 int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
 227                         BlockReopenQueue *queue, Error **errp);
 228 void bdrv_reopen_commit(BDRVReopenState *reopen_state);
 229 void bdrv_reopen_abort(BDRVReopenState *reopen_state);
 230 void bdrv_close(BlockDriverState *bs);
 231 void bdrv_add_close_notifier(BlockDriverState *bs, Notifier *notify);
 232 int bdrv_attach_dev(BlockDriverState *bs, void *dev);
 233 void bdrv_attach_dev_nofail(BlockDriverState *bs, void *dev);
 234 void bdrv_detach_dev(BlockDriverState *bs, void *dev);
 235 void *bdrv_get_attached_dev(BlockDriverState *bs);
 236 void bdrv_set_dev_ops(BlockDriverState *bs, const BlockDevOps *ops,
 237                       void *opaque);
 238 void bdrv_dev_eject_request(BlockDriverState *bs, bool force);
 239 bool bdrv_dev_has_removable_media(BlockDriverState *bs);
 240 bool bdrv_dev_is_tray_open(BlockDriverState *bs);
 241 bool bdrv_dev_is_medium_locked(BlockDriverState *bs);
 242 int bdrv_read(BlockDriverState *bs, int64_t sector_num,
 243               uint8_t *buf, int nb_sectors);
 244 int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
 245                           uint8_t *buf, int nb_sectors);
 246 int bdrv_write(BlockDriverState *bs, int64_t sector_num,
 247                const uint8_t *buf, int nb_sectors);
 248 int bdrv_write_zeroes(BlockDriverState *bs, int64_t sector_num,
 249                int nb_sectors, BdrvRequestFlags flags);
 250 BlockDriverAIOCB *bdrv_aio_write_zeroes(BlockDriverState *bs, int64_t sector_num,
 251                                         int nb_sectors, BdrvRequestFlags flags,
 252                                         BlockDriverCompletionFunc *cb, void *opaque);
 253 int bdrv_make_zero(BlockDriverState *bs, BdrvRequestFlags flags);
 254 int bdrv_pread(BlockDriverState *bs, int64_t offset,
 255                void *buf, int count);
 256 int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
 257                 const void *buf, int count);
 258 int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov);
 259 int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
 260     const void *buf, int count);
 261 int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num,
 262     int nb_sectors, QEMUIOVector *qiov);
 263 int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
 264     int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
 265 int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,
 266     int nb_sectors, QEMUIOVector *qiov);
 267 /*
 268  * Efficiently zero a region of the disk image.  Note that this is a regular
 269  * I/O request like read or write and should have a reasonable size.  This
 270  * function is not suitable for zeroing the entire image in a single request
 271  * because it may allocate memory for the entire region.
 272  */
 273 int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
 274     int nb_sectors, BdrvRequestFlags flags);
 275 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
 276     const char *backing_file);
 277 int bdrv_get_backing_file_depth(BlockDriverState *bs);
 278 void bdrv_refresh_filename(BlockDriverState *bs);
 279 int bdrv_truncate(BlockDriverState *bs, int64_t offset);
 280 int64_t bdrv_nb_sectors(BlockDriverState *bs);
 281 int64_t bdrv_getlength(BlockDriverState *bs);
 282 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs);
 283 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
 284 void bdrv_refresh_limits(BlockDriverState *bs, Error **errp);
 285 int bdrv_commit(BlockDriverState *bs);
 286 int bdrv_commit_all(void);
 287 int bdrv_change_backing_file(BlockDriverState *bs,
 288     const char *backing_file, const char *backing_fmt);
 289 void bdrv_register(BlockDriver *bdrv);
 290 int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
 291                            BlockDriverState *base,
 292                            const char *backing_file_str);
 293 BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
 294                                     BlockDriverState *bs);
 295 BlockDriverState *bdrv_find_base(BlockDriverState *bs);
 296
 297
 298 typedef struct BdrvCheckResult {
 299     int corruptions;
 300     int leaks;
 301     int check_errors;
 302     int corruptions_fixed;
 303     int leaks_fixed;
 304     int64_t image_end_offset;
 305     BlockFragInfo bfi;
 306 } BdrvCheckResult;
 307
 308 typedef enum {
 309     BDRV_FIX_LEAKS    = 1,
 310     BDRV_FIX_ERRORS   = 2,
 311 } BdrvCheckMode;
 312
 313 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
 314
 315 int bdrv_amend_options(BlockDriverState *bs_new, QemuOpts *opts);
 316
 317 /* external snapshots */
 318 bool bdrv_recurse_is_first_non_filter(BlockDriverState *bs,
 319                                       BlockDriverState *candidate);
 320 bool bdrv_is_first_non_filter(BlockDriverState *candidate);
 321
 322 /* check if a named node can be replaced when doing drive-mirror */
 323 BlockDriverState *check_to_replace_node(const char *node_name, Error **errp);
 324
 325 /* async block I/O */
 326 typedef void BlockDriverDirtyHandler(BlockDriverState *bs, int64_t sector,
 327                                      int sector_num);
 328 BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
 329                                  QEMUIOVector *iov, int nb_sectors,
 330                                  BlockDriverCompletionFunc *cb, void *opaque);
 331 BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
 332                                   QEMUIOVector *iov, int nb_sectors,
 333                                   BlockDriverCompletionFunc *cb, void *opaque);
 334 BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
 335                                  BlockDriverCompletionFunc *cb, void *opaque);
 336 BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs,
 337                                    int64_t sector_num, int nb_sectors,
 338                                    BlockDriverCompletionFunc *cb, void *opaque);
 339 void bdrv_aio_cancel(BlockDriverAIOCB *acb);
 340 void bdrv_aio_cancel_async(BlockDriverAIOCB *acb);
 341
 342 typedef struct BlockRequest {
 343     /* Fields to be filled by multiwrite caller */
 344     int64_t sector;
 345     int nb_sectors;
 346     int flags;
 347     QEMUIOVector *qiov;
 348     BlockDriverCompletionFunc *cb;
 349     void *opaque;
 350
 351     /* Filled by multiwrite implementation */
 352     int error;
 353 } BlockRequest;
 354
 355 int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs,
 356     int num_reqs);
 357
 358 /* sg packet commands */
 359 int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf);
 360 BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
 361         unsigned long int req, void *buf,
 362         BlockDriverCompletionFunc *cb, void *opaque);
 363
 364 /* Invalidate any cached metadata used by image formats */
 365 void bdrv_invalidate_cache(BlockDriverState *bs, Error **errp);
 366 void bdrv_invalidate_cache_all(Error **errp);
 367
 368 void bdrv_clear_incoming_migration_all(void);
 369
 370 /* Ensure contents are flushed to disk.  */
 371 int bdrv_flush(BlockDriverState *bs);
 372 int coroutine_fn bdrv_co_flush(BlockDriverState *bs);
 373 int bdrv_flush_all(void);
 374 void bdrv_close_all(void);
 375 void bdrv_drain_all(void);
 376
 377 int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
 378 int bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
 379 int bdrv_has_zero_init_1(BlockDriverState *bs);
 380 int bdrv_has_zero_init(BlockDriverState *bs);
 381 bool bdrv_unallocated_blocks_are_zero(BlockDriverState *bs);
 382 bool bdrv_can_write_zeroes_with_unmap(BlockDriverState *bs);
 383 int64_t bdrv_get_block_status(BlockDriverState *bs, int64_t sector_num,
 384                               int nb_sectors, int *pnum);
 385 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
 386                       int *pnum);
 387 int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,
 388                             int64_t sector_num, int nb_sectors, int *pnum);
 389
 390 void bdrv_set_on_error(BlockDriverState *bs, BlockdevOnError on_read_error,
 391                        BlockdevOnError on_write_error);
 392 BlockdevOnError bdrv_get_on_error(BlockDriverState *bs, bool is_read);
 393 BlockErrorAction bdrv_get_error_action(BlockDriverState *bs, bool is_read, int error);
 394 void bdrv_error_action(BlockDriverState *bs, BlockErrorAction action,
 395                        bool is_read, int error);
 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 int 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(const char *name);
 406 BlockDriverState *bdrv_find_node(const char *node_name);
 407 BlockDeviceInfoList *bdrv_named_nodes_list(void);
 408 BlockDriverState *bdrv_lookup_bs(const char *device,
 409                                  const char *node_name,
 410                                  Error **errp);
 411 bool bdrv_chain_contains(BlockDriverState *top, BlockDriverState *base);
 412 BlockDriverState *bdrv_next(BlockDriverState *bs);
 413 void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs),
 414                   void *opaque);
 415 int bdrv_is_encrypted(BlockDriverState *bs);
 416 int bdrv_key_required(BlockDriverState *bs);
 417 int bdrv_set_key(BlockDriverState *bs, const char *key);
 418 int bdrv_query_missing_keys(void);
 419 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
 420                          void *opaque);
 421 const char *bdrv_get_device_name(BlockDriverState *bs);
 422 int bdrv_get_flags(BlockDriverState *bs);
 423 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
 424                           const uint8_t *buf, int nb_sectors);
 425 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi);
 426 ImageInfoSpecific *bdrv_get_specific_info(BlockDriverState *bs);
 427 void bdrv_round_to_clusters(BlockDriverState *bs,
 428                             int64_t sector_num, int nb_sectors,
 429                             int64_t *cluster_sector_num,
 430                             int *cluster_nb_sectors);
 431
 432 const char *bdrv_get_encrypted_filename(BlockDriverState *bs);
 433 void bdrv_get_backing_filename(BlockDriverState *bs,
 434                                char *filename, int filename_size);
 435 void bdrv_get_full_backing_filename(BlockDriverState *bs,
 436                                     char *dest, size_t sz);
 437 int bdrv_is_snapshot(BlockDriverState *bs);
 438
 439 int path_is_absolute(const char *path);
 440 void path_combine(char *dest, int dest_size,
 441                   const char *base_path,
 442                   const char *filename);
 443
 444 int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos);
 445 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
 446                       int64_t pos, int size);
 447
 448 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
 449                       int64_t pos, int size);
 450
 451 void bdrv_img_create(const char *filename, const char *fmt,
 452                      const char *base_filename, const char *base_fmt,
 453                      char *options, uint64_t img_size, int flags,
 454                      Error **errp, bool quiet);
 455
 456 /* Returns the alignment in bytes that is required so that no bounce buffer
 457  * is required throughout the stack */
 458 size_t bdrv_opt_mem_align(BlockDriverState *bs);
 459 void bdrv_set_guest_block_size(BlockDriverState *bs, int align);
 460 void *qemu_blockalign(BlockDriverState *bs, size_t size);
 461 void *qemu_try_blockalign(BlockDriverState *bs, size_t size);
 462 bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov);
 463
 464 struct HBitmapIter;
 465 typedef struct BdrvDirtyBitmap BdrvDirtyBitmap;
 466 BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, int granularity,
 467                                           Error **errp);
 468 void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
 469 BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
 470 int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, int64_t sector);
 471 void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors);
 472 void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors);
 473 void bdrv_dirty_iter_init(BlockDriverState *bs,
 474                           BdrvDirtyBitmap *bitmap, struct HBitmapIter *hbi);
 475 int64_t bdrv_get_dirty_count(BlockDriverState *bs, BdrvDirtyBitmap *bitmap);
 476
 477 void bdrv_enable_copy_on_read(BlockDriverState *bs);
 478 void bdrv_disable_copy_on_read(BlockDriverState *bs);
 479
 480 void bdrv_ref(BlockDriverState *bs);
 481 void bdrv_unref(BlockDriverState *bs);
 482
 483 bool bdrv_op_is_blocked(BlockDriverState *bs, BlockOpType op, Error **errp);
 484 void bdrv_op_block(BlockDriverState *bs, BlockOpType op, Error *reason);
 485 void bdrv_op_unblock(BlockDriverState *bs, BlockOpType op, Error *reason);
 486 void bdrv_op_block_all(BlockDriverState *bs, Error *reason);
 487 void bdrv_op_unblock_all(BlockDriverState *bs, Error *reason);
 488 bool bdrv_op_blocker_is_empty(BlockDriverState *bs);
 489
 490 typedef enum {
 491     BLKDBG_L1_UPDATE,
 492
 493     BLKDBG_L1_GROW_ALLOC_TABLE,
 494     BLKDBG_L1_GROW_WRITE_TABLE,
 495     BLKDBG_L1_GROW_ACTIVATE_TABLE,
 496
 497     BLKDBG_L2_LOAD,
 498     BLKDBG_L2_UPDATE,
 499     BLKDBG_L2_UPDATE_COMPRESSED,
 500     BLKDBG_L2_ALLOC_COW_READ,
 501     BLKDBG_L2_ALLOC_WRITE,
 502
 503     BLKDBG_READ_AIO,
 504     BLKDBG_READ_BACKING_AIO,
 505     BLKDBG_READ_COMPRESSED,
 506
 507     BLKDBG_WRITE_AIO,
 508     BLKDBG_WRITE_COMPRESSED,
 509
 510     BLKDBG_VMSTATE_LOAD,
 511     BLKDBG_VMSTATE_SAVE,
 512
 513     BLKDBG_COW_READ,
 514     BLKDBG_COW_WRITE,
 515
 516     BLKDBG_REFTABLE_LOAD,
 517     BLKDBG_REFTABLE_GROW,
 518     BLKDBG_REFTABLE_UPDATE,
 519
 520     BLKDBG_REFBLOCK_LOAD,
 521     BLKDBG_REFBLOCK_UPDATE,
 522     BLKDBG_REFBLOCK_UPDATE_PART,
 523     BLKDBG_REFBLOCK_ALLOC,
 524     BLKDBG_REFBLOCK_ALLOC_HOOKUP,
 525     BLKDBG_REFBLOCK_ALLOC_WRITE,
 526     BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS,
 527     BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE,
 528     BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE,
 529
 530     BLKDBG_CLUSTER_ALLOC,
 531     BLKDBG_CLUSTER_ALLOC_BYTES,
 532     BLKDBG_CLUSTER_FREE,
 533
 534     BLKDBG_FLUSH_TO_OS,
 535     BLKDBG_FLUSH_TO_DISK,
 536
 537     BLKDBG_PWRITEV_RMW_HEAD,
 538     BLKDBG_PWRITEV_RMW_AFTER_HEAD,
 539     BLKDBG_PWRITEV_RMW_TAIL,
 540     BLKDBG_PWRITEV_RMW_AFTER_TAIL,
 541     BLKDBG_PWRITEV,
 542     BLKDBG_PWRITEV_ZERO,
 543     BLKDBG_PWRITEV_DONE,
 544
 545     BLKDBG_EVENT_MAX,
 546 } BlkDebugEvent;
 547
 548 #define BLKDBG_EVENT(bs, evt) bdrv_debug_event(bs, evt)
 549 void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event);
 550
 551 int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
 552                            const char *tag);
 553 int bdrv_debug_remove_breakpoint(BlockDriverState *bs, const char *tag);
 554 int bdrv_debug_resume(BlockDriverState *bs, const char *tag);
 555 bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag);
 556
 557 /**
 558  * bdrv_get_aio_context:
 559  *
 560  * Returns: the currently bound #AioContext
 561  */
 562 AioContext *bdrv_get_aio_context(BlockDriverState *bs);
 563
 564 /**
 565  * bdrv_set_aio_context:
 566  *
 567  * Changes the #AioContext used for fd handlers, timers, and BHs by this
 568  * BlockDriverState and all its children.
 569  *
 570  * This function must be called from the old #AioContext or with a lock held so
 571  * the old #AioContext is not executing.
 572  */
 573 void bdrv_set_aio_context(BlockDriverState *bs, AioContext *new_context);
 574
 575 void bdrv_io_plug(BlockDriverState *bs);
 576 void bdrv_io_unplug(BlockDriverState *bs);
 577 void bdrv_flush_io_queue(BlockDriverState *bs);
 578
 579 BlockAcctStats *bdrv_get_stats(BlockDriverState *bs);
 580
 581 #endif