block.h

   1 #ifndef BLOCK_H
   2 #define BLOCK_H
   3
   4 #include "qemu-aio.h"
   5 #include "qemu-common.h"
   6 #include "qemu-option.h"
   7 #include "qemu-coroutine.h"
   8 #include "qobject.h"
   9 #include "qapi-types.h"
  10
  11 /* block.c */
  12 typedef struct BlockDriver BlockDriver;
  13 typedef struct BlockJob BlockJob;
  14
  15 typedef struct BlockDriverInfo {
  16     /* in bytes, 0 if irrelevant */
  17     int cluster_size;
  18     /* offset at which the VM state can be saved (0 if not possible) */
  19     int64_t vm_state_offset;
  20     bool is_dirty;
  21 } BlockDriverInfo;
  22
  23 typedef struct BlockFragInfo {
  24     uint64_t allocated_clusters;
  25     uint64_t total_clusters;
  26     uint64_t fragmented_clusters;
  27 } BlockFragInfo;
  28
  29 typedef struct QEMUSnapshotInfo {
  30     char id_str[128]; /* unique snapshot id */
  31     /* the following fields are informative. They are not needed for
  32        the consistency of the snapshot */
  33     char name[256]; /* user chosen name */
  34     uint64_t vm_state_size; /* VM state info size */
  35     uint32_t date_sec; /* UTC date of the snapshot */
  36     uint32_t date_nsec;
  37     uint64_t vm_clock_nsec; /* VM clock relative to boot */
  38 } QEMUSnapshotInfo;
  39
  40 /* Callbacks for block device models */
  41 typedef struct BlockDevOps {
  42     /*
  43      * Runs when virtual media changed (monitor commands eject, change)
  44      * Argument load is true on load and false on eject.
  45      * Beware: doesn't run when a host device's physical media
  46      * changes.  Sure would be useful if it did.
  47      * Device models with removable media must implement this callback.
  48      */
  49     void (*change_media_cb)(void *opaque, bool load);
  50     /*
  51      * Runs when an eject request is issued from the monitor, the tray
  52      * is closed, and the medium is locked.
  53      * Device models that do not implement is_medium_locked will not need
  54      * this callback.  Device models that can lock the medium or tray might
  55      * want to implement the callback and unlock the tray when "force" is
  56      * true, even if they do not support eject requests.
  57      */
  58     void (*eject_request_cb)(void *opaque, bool force);
  59     /*
  60      * Is the virtual tray open?
  61      * Device models implement this only when the device has a tray.
  62      */
  63     bool (*is_tray_open)(void *opaque);
  64     /*
  65      * Is the virtual medium locked into the device?
  66      * Device models implement this only when device has such a lock.
  67      */
  68     bool (*is_medium_locked)(void *opaque);
  69     /*
  70      * Runs when the size changed (e.g. monitor command block_resize)
  71      */
  72     void (*resize_cb)(void *opaque);
  73 } BlockDevOps;
  74
  75 #define BDRV_O_RDWR        0x0002
  76 #define BDRV_O_SNAPSHOT    0x0008 /* open the file read only and save writes in a snapshot */
  77 #define BDRV_O_NOCACHE     0x0020 /* do not use the host page cache */
  78 #define BDRV_O_CACHE_WB    0x0040 /* use write-back caching */
  79 #define BDRV_O_NATIVE_AIO  0x0080 /* use native AIO instead of the thread pool */
  80 #define BDRV_O_NO_BACKING  0x0100 /* don't open the backing file */
  81 #define BDRV_O_NO_FLUSH    0x0200 /* disable flushing on this disk */
  82 #define BDRV_O_COPY_ON_READ 0x0400 /* copy read backing sectors into image */
  83 #define BDRV_O_INCOMING    0x0800  /* consistency hint for incoming migration */
  84 #define BDRV_O_CHECK       0x1000  /* open solely for consistency check */
  85 #define BDRV_O_ALLOW_RDWR  0x2000  /* allow reopen to change from r/o to r/w */
  86
  87 #define BDRV_O_CACHE_MASK  (BDRV_O_NOCACHE | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH)
  88
  89 #define BDRV_SECTOR_BITS   9
  90 #define BDRV_SECTOR_SIZE   (1ULL << BDRV_SECTOR_BITS)
  91 #define BDRV_SECTOR_MASK   ~(BDRV_SECTOR_SIZE - 1)
  92
  93 typedef enum {
  94     BDRV_ACTION_REPORT, BDRV_ACTION_IGNORE, BDRV_ACTION_STOP
  95 } BlockErrorAction;
  96
  97 typedef QSIMPLEQ_HEAD(BlockReopenQueue, BlockReopenQueueEntry) BlockReopenQueue;
  98
  99 typedef struct BDRVReopenState {
 100     BlockDriverState *bs;
 101     int flags;
 102     void *opaque;
 103 } BDRVReopenState;
 104
 105
 106 void bdrv_iostatus_enable(BlockDriverState *bs);
 107 void bdrv_iostatus_reset(BlockDriverState *bs);
 108 void bdrv_iostatus_disable(BlockDriverState *bs);
 109 bool bdrv_iostatus_is_enabled(const BlockDriverState *bs);
 110 void bdrv_iostatus_set_err(BlockDriverState *bs, int error);
 111 void bdrv_info_print(Monitor *mon, const QObject *data);
 112 void bdrv_info(Monitor *mon, QObject **ret_data);
 113 void bdrv_stats_print(Monitor *mon, const QObject *data);
 114 void bdrv_info_stats(Monitor *mon, QObject **ret_data);
 115
 116 /* disk I/O throttling */
 117 void bdrv_io_limits_enable(BlockDriverState *bs);
 118 void bdrv_io_limits_disable(BlockDriverState *bs);
 119 bool bdrv_io_limits_enabled(BlockDriverState *bs);
 120
 121 void bdrv_init(void);
 122 void bdrv_init_with_whitelist(void);
 123 BlockDriver *bdrv_find_protocol(const char *filename);
 124 BlockDriver *bdrv_find_format(const char *format_name);
 125 BlockDriver *bdrv_find_whitelisted_format(const char *format_name);
 126 int bdrv_create(BlockDriver *drv, const char* filename,
 127     QEMUOptionParameter *options);
 128 int bdrv_create_file(const char* filename, QEMUOptionParameter *options);
 129 BlockDriverState *bdrv_new(const char *device_name);
 130 void bdrv_make_anon(BlockDriverState *bs);
 131 void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old);
 132 void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top);
 133 void bdrv_delete(BlockDriverState *bs);
 134 int bdrv_parse_cache_flags(const char *mode, int *flags);
 135 int bdrv_file_open(BlockDriverState **pbs, const char *filename, int flags);
 136 int bdrv_open(BlockDriverState *bs, const char *filename, int flags,
 137               BlockDriver *drv);
 138 BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
 139                                     BlockDriverState *bs, int flags);
 140 int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp);
 141 int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp);
 142 int bdrv_reopen_prepare(BDRVReopenState *reopen_state,
 143                         BlockReopenQueue *queue, Error **errp);
 144 void bdrv_reopen_commit(BDRVReopenState *reopen_state);
 145 void bdrv_reopen_abort(BDRVReopenState *reopen_state);
 146 void bdrv_close(BlockDriverState *bs);
 147 int bdrv_attach_dev(BlockDriverState *bs, void *dev);
 148 void bdrv_attach_dev_nofail(BlockDriverState *bs, void *dev);
 149 void bdrv_detach_dev(BlockDriverState *bs, void *dev);
 150 void *bdrv_get_attached_dev(BlockDriverState *bs);
 151 void bdrv_set_dev_ops(BlockDriverState *bs, const BlockDevOps *ops,
 152                       void *opaque);
 153 void bdrv_dev_eject_request(BlockDriverState *bs, bool force);
 154 bool bdrv_dev_has_removable_media(BlockDriverState *bs);
 155 bool bdrv_dev_is_tray_open(BlockDriverState *bs);
 156 bool bdrv_dev_is_medium_locked(BlockDriverState *bs);
 157 int bdrv_read(BlockDriverState *bs, int64_t sector_num,
 158               uint8_t *buf, int nb_sectors);
 159 int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
 160                           uint8_t *buf, int nb_sectors);
 161 int bdrv_write(BlockDriverState *bs, int64_t sector_num,
 162                const uint8_t *buf, int nb_sectors);
 163 int bdrv_pread(BlockDriverState *bs, int64_t offset,
 164                void *buf, int count);
 165 int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
 166                 const void *buf, int count);
 167 int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
 168     const void *buf, int count);
 169 int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num,
 170     int nb_sectors, QEMUIOVector *qiov);
 171 int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
 172     int64_t sector_num, int nb_sectors, QEMUIOVector *qiov);
 173 int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,
 174     int nb_sectors, QEMUIOVector *qiov);
 175 /*
 176  * Efficiently zero a region of the disk image.  Note that this is a regular
 177  * I/O request like read or write and should have a reasonable size.  This
 178  * function is not suitable for zeroing the entire image in a single request
 179  * because it may allocate memory for the entire region.
 180  */
 181 int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs, int64_t sector_num,
 182     int nb_sectors);
 183 int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num,
 184     int nb_sectors, int *pnum);
 185 int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top,
 186                                             BlockDriverState *base,
 187                                             int64_t sector_num,
 188                                             int nb_sectors, int *pnum);
 189 BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
 190     const char *backing_file);
 191 int bdrv_get_backing_file_depth(BlockDriverState *bs);
 192 int bdrv_truncate(BlockDriverState *bs, int64_t offset);
 193 int64_t bdrv_getlength(BlockDriverState *bs);
 194 int64_t bdrv_get_allocated_file_size(BlockDriverState *bs);
 195 void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr);
 196 int bdrv_commit(BlockDriverState *bs);
 197 int bdrv_commit_all(void);
 198 int bdrv_change_backing_file(BlockDriverState *bs,
 199     const char *backing_file, const char *backing_fmt);
 200 void bdrv_register(BlockDriver *bdrv);
 201 int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
 202                            BlockDriverState *base);
 203 BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
 204                                     BlockDriverState *bs);
 205 BlockDriverState *bdrv_find_base(BlockDriverState *bs);
 206
 207
 208 typedef struct BdrvCheckResult {
 209     int corruptions;
 210     int leaks;
 211     int check_errors;
 212     int corruptions_fixed;
 213     int leaks_fixed;
 214     BlockFragInfo bfi;
 215 } BdrvCheckResult;
 216
 217 typedef enum {
 218     BDRV_FIX_LEAKS    = 1,
 219     BDRV_FIX_ERRORS   = 2,
 220 } BdrvCheckMode;
 221
 222 int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix);
 223
 224 /* async block I/O */
 225 typedef void BlockDriverDirtyHandler(BlockDriverState *bs, int64_t sector,
 226                                      int sector_num);
 227 BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
 228                                  QEMUIOVector *iov, int nb_sectors,
 229                                  BlockDriverCompletionFunc *cb, void *opaque);
 230 BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
 231                                   QEMUIOVector *iov, int nb_sectors,
 232                                   BlockDriverCompletionFunc *cb, void *opaque);
 233 BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
 234                                  BlockDriverCompletionFunc *cb, void *opaque);
 235 BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs,
 236                                    int64_t sector_num, int nb_sectors,
 237                                    BlockDriverCompletionFunc *cb, void *opaque);
 238 void bdrv_aio_cancel(BlockDriverAIOCB *acb);
 239
 240 typedef struct BlockRequest {
 241     /* Fields to be filled by multiwrite caller */
 242     int64_t sector;
 243     int nb_sectors;
 244     QEMUIOVector *qiov;
 245     BlockDriverCompletionFunc *cb;
 246     void *opaque;
 247
 248     /* Filled by multiwrite implementation */
 249     int error;
 250 } BlockRequest;
 251
 252 int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs,
 253     int num_reqs);
 254
 255 /* sg packet commands */
 256 int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf);
 257 BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
 258         unsigned long int req, void *buf,
 259         BlockDriverCompletionFunc *cb, void *opaque);
 260
 261 /* Invalidate any cached metadata used by image formats */
 262 void bdrv_invalidate_cache(BlockDriverState *bs);
 263 void bdrv_invalidate_cache_all(void);
 264
 265 void bdrv_clear_incoming_migration_all(void);
 266
 267 /* Ensure contents are flushed to disk.  */
 268 int bdrv_flush(BlockDriverState *bs);
 269 int coroutine_fn bdrv_co_flush(BlockDriverState *bs);
 270 void bdrv_flush_all(void);
 271 void bdrv_close_all(void);
 272 void bdrv_drain_all(void);
 273
 274 int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
 275 int bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors);
 276 int bdrv_has_zero_init(BlockDriverState *bs);
 277 int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
 278                       int *pnum);
 279
 280 void bdrv_set_on_error(BlockDriverState *bs, BlockdevOnError on_read_error,
 281                        BlockdevOnError on_write_error);
 282 BlockdevOnError bdrv_get_on_error(BlockDriverState *bs, bool is_read);
 283 BlockErrorAction bdrv_get_error_action(BlockDriverState *bs, bool is_read, int error);
 284 void bdrv_error_action(BlockDriverState *bs, BlockErrorAction action,
 285                        bool is_read, int error);
 286 int bdrv_is_read_only(BlockDriverState *bs);
 287 int bdrv_is_sg(BlockDriverState *bs);
 288 int bdrv_enable_write_cache(BlockDriverState *bs);
 289 void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce);
 290 int bdrv_is_inserted(BlockDriverState *bs);
 291 int bdrv_media_changed(BlockDriverState *bs);
 292 void bdrv_lock_medium(BlockDriverState *bs, bool locked);
 293 void bdrv_eject(BlockDriverState *bs, bool eject_flag);
 294 const char *bdrv_get_format_name(BlockDriverState *bs);
 295 BlockDriverState *bdrv_find(const char *name);
 296 BlockDriverState *bdrv_next(BlockDriverState *bs);
 297 void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs),
 298                   void *opaque);
 299 int bdrv_is_encrypted(BlockDriverState *bs);
 300 int bdrv_key_required(BlockDriverState *bs);
 301 int bdrv_set_key(BlockDriverState *bs, const char *key);
 302 int bdrv_query_missing_keys(void);
 303 void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
 304                          void *opaque);
 305 const char *bdrv_get_device_name(BlockDriverState *bs);
 306 int bdrv_get_flags(BlockDriverState *bs);
 307 int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
 308                           const uint8_t *buf, int nb_sectors);
 309 int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi);
 310
 311 const char *bdrv_get_encrypted_filename(BlockDriverState *bs);
 312 void bdrv_get_backing_filename(BlockDriverState *bs,
 313                                char *filename, int filename_size);
 314 void bdrv_get_full_backing_filename(BlockDriverState *bs,
 315                                     char *dest, size_t sz);
 316 int bdrv_can_snapshot(BlockDriverState *bs);
 317 int bdrv_is_snapshot(BlockDriverState *bs);
 318 BlockDriverState *bdrv_snapshots(void);
 319 int bdrv_snapshot_create(BlockDriverState *bs,
 320                          QEMUSnapshotInfo *sn_info);
 321 int bdrv_snapshot_goto(BlockDriverState *bs,
 322                        const char *snapshot_id);
 323 int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id);
 324 int bdrv_snapshot_list(BlockDriverState *bs,
 325                        QEMUSnapshotInfo **psn_info);
 326 int bdrv_snapshot_load_tmp(BlockDriverState *bs,
 327                            const char *snapshot_name);
 328 char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn);
 329
 330 char *get_human_readable_size(char *buf, int buf_size, int64_t size);
 331 int path_is_absolute(const char *path);
 332 void path_combine(char *dest, int dest_size,
 333                   const char *base_path,
 334                   const char *filename);
 335
 336 int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
 337                       int64_t pos, int size);
 338
 339 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
 340                       int64_t pos, int size);
 341
 342 int bdrv_img_create(const char *filename, const char *fmt,
 343                     const char *base_filename, const char *base_fmt,
 344                     char *options, uint64_t img_size, int flags);
 345
 346 void bdrv_set_buffer_alignment(BlockDriverState *bs, int align);
 347 void *qemu_blockalign(BlockDriverState *bs, size_t size);
 348
 349 #define BDRV_SECTORS_PER_DIRTY_CHUNK 2048
 350
 351 void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable);
 352 int bdrv_get_dirty(BlockDriverState *bs, int64_t sector);
 353 void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
 354                       int nr_sectors);
 355 int64_t bdrv_get_dirty_count(BlockDriverState *bs);
 356
 357 void bdrv_enable_copy_on_read(BlockDriverState *bs);
 358 void bdrv_disable_copy_on_read(BlockDriverState *bs);
 359
 360 void bdrv_set_in_use(BlockDriverState *bs, int in_use);
 361 int bdrv_in_use(BlockDriverState *bs);
 362
 363 enum BlockAcctType {
 364     BDRV_ACCT_READ,
 365     BDRV_ACCT_WRITE,
 366     BDRV_ACCT_FLUSH,
 367     BDRV_MAX_IOTYPE,
 368 };
 369
 370 typedef struct BlockAcctCookie {
 371     int64_t bytes;
 372     int64_t start_time_ns;
 373     enum BlockAcctType type;
 374 } BlockAcctCookie;
 375
 376 void bdrv_acct_start(BlockDriverState *bs, BlockAcctCookie *cookie,
 377         int64_t bytes, enum BlockAcctType type);
 378 void bdrv_acct_done(BlockDriverState *bs, BlockAcctCookie *cookie);
 379
 380 typedef enum {
 381     BLKDBG_L1_UPDATE,
 382
 383     BLKDBG_L1_GROW_ALLOC_TABLE,
 384     BLKDBG_L1_GROW_WRITE_TABLE,
 385     BLKDBG_L1_GROW_ACTIVATE_TABLE,
 386
 387     BLKDBG_L2_LOAD,
 388     BLKDBG_L2_UPDATE,
 389     BLKDBG_L2_UPDATE_COMPRESSED,
 390     BLKDBG_L2_ALLOC_COW_READ,
 391     BLKDBG_L2_ALLOC_WRITE,
 392
 393     BLKDBG_READ_AIO,
 394     BLKDBG_READ_BACKING_AIO,
 395     BLKDBG_READ_COMPRESSED,
 396
 397     BLKDBG_WRITE_AIO,
 398     BLKDBG_WRITE_COMPRESSED,
 399
 400     BLKDBG_VMSTATE_LOAD,
 401     BLKDBG_VMSTATE_SAVE,
 402
 403     BLKDBG_COW_READ,
 404     BLKDBG_COW_WRITE,
 405
 406     BLKDBG_REFTABLE_LOAD,
 407     BLKDBG_REFTABLE_GROW,
 408
 409     BLKDBG_REFBLOCK_LOAD,
 410     BLKDBG_REFBLOCK_UPDATE,
 411     BLKDBG_REFBLOCK_UPDATE_PART,
 412     BLKDBG_REFBLOCK_ALLOC,
 413     BLKDBG_REFBLOCK_ALLOC_HOOKUP,
 414     BLKDBG_REFBLOCK_ALLOC_WRITE,
 415     BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS,
 416     BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE,
 417     BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE,
 418
 419     BLKDBG_CLUSTER_ALLOC,
 420     BLKDBG_CLUSTER_ALLOC_BYTES,
 421     BLKDBG_CLUSTER_FREE,
 422
 423     BLKDBG_EVENT_MAX,
 424 } BlkDebugEvent;
 425
 426 #define BLKDBG_EVENT(bs, evt) bdrv_debug_event(bs, evt)
 427 void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event);
 428
 429 #endif