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