1 /* 2 * QEMU System Emulator block driver 3 * 4 * Copyright (c) 2003 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 #ifndef BLOCK_INT_H 25 #define BLOCK_INT_H 26 27 #include "block/block.h" 28 #include "qemu/option.h" 29 #include "qemu/queue.h" 30 #include "block/coroutine.h" 31 #include "qemu/timer.h" 32 #include "qapi-types.h" 33 #include "qapi/qmp/qerror.h" 34 #include "monitor/monitor.h" 35 #include "qemu/hbitmap.h" 36 37 #define BLOCK_FLAG_ENCRYPT 1 38 #define BLOCK_FLAG_COMPAT6 4 39 #define BLOCK_FLAG_LAZY_REFCOUNTS 8 40 41 #define BLOCK_IO_LIMIT_READ 0 42 #define BLOCK_IO_LIMIT_WRITE 1 43 #define BLOCK_IO_LIMIT_TOTAL 2 44 45 #define BLOCK_IO_SLICE_TIME 100000000 46 #define NANOSECONDS_PER_SECOND 1000000000.0 47 48 #define BLOCK_OPT_SIZE "size" 49 #define BLOCK_OPT_ENCRYPT "encryption" 50 #define BLOCK_OPT_COMPAT6 "compat6" 51 #define BLOCK_OPT_BACKING_FILE "backing_file" 52 #define BLOCK_OPT_BACKING_FMT "backing_fmt" 53 #define BLOCK_OPT_CLUSTER_SIZE "cluster_size" 54 #define BLOCK_OPT_TABLE_SIZE "table_size" 55 #define BLOCK_OPT_PREALLOC "preallocation" 56 #define BLOCK_OPT_SUBFMT "subformat" 57 #define BLOCK_OPT_COMPAT_LEVEL "compat" 58 #define BLOCK_OPT_LAZY_REFCOUNTS "lazy_refcounts" 59 #define BLOCK_OPT_ADAPTER_TYPE "adapter_type" 60 61 typedef struct BdrvTrackedRequest BdrvTrackedRequest; 62 63 typedef struct BlockIOLimit { 64 int64_t bps[3]; 65 int64_t iops[3]; 66 } BlockIOLimit; 67 68 typedef struct BlockIOBaseValue { 69 uint64_t bytes[2]; 70 uint64_t ios[2]; 71 } BlockIOBaseValue; 72 73 struct BlockDriver { 74 const char *format_name; 75 int instance_size; 76 int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename); 77 int (*bdrv_probe_device)(const char *filename); 78 79 /* Any driver implementing this callback is expected to be able to handle 80 * NULL file names in its .bdrv_open() implementation */ 81 void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp); 82 83 /* For handling image reopen for split or non-split files */ 84 int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state, 85 BlockReopenQueue *queue, Error **errp); 86 void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state); 87 void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state); 88 89 int (*bdrv_open)(BlockDriverState *bs, QDict *options, int flags); 90 int (*bdrv_file_open)(BlockDriverState *bs, QDict *options, int flags); 91 int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num, 92 uint8_t *buf, int nb_sectors); 93 int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num, 94 const uint8_t *buf, int nb_sectors); 95 void (*bdrv_close)(BlockDriverState *bs); 96 void (*bdrv_rebind)(BlockDriverState *bs); 97 int (*bdrv_create)(const char *filename, QEMUOptionParameter *options); 98 int (*bdrv_set_key)(BlockDriverState *bs, const char *key); 99 int (*bdrv_make_empty)(BlockDriverState *bs); 100 /* aio */ 101 BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs, 102 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 103 BlockDriverCompletionFunc *cb, void *opaque); 104 BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs, 105 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 106 BlockDriverCompletionFunc *cb, void *opaque); 107 BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs, 108 BlockDriverCompletionFunc *cb, void *opaque); 109 BlockDriverAIOCB *(*bdrv_aio_discard)(BlockDriverState *bs, 110 int64_t sector_num, int nb_sectors, 111 BlockDriverCompletionFunc *cb, void *opaque); 112 113 int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs, 114 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); 115 int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs, 116 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); 117 /* 118 * Efficiently zero a region of the disk image. Typically an image format 119 * would use a compact metadata representation to implement this. This 120 * function pointer may be NULL and .bdrv_co_writev() will be called 121 * instead. 122 */ 123 int coroutine_fn (*bdrv_co_write_zeroes)(BlockDriverState *bs, 124 int64_t sector_num, int nb_sectors); 125 int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs, 126 int64_t sector_num, int nb_sectors); 127 int coroutine_fn (*bdrv_co_is_allocated)(BlockDriverState *bs, 128 int64_t sector_num, int nb_sectors, int *pnum); 129 130 /* 131 * Invalidate any cached meta-data. 132 */ 133 void (*bdrv_invalidate_cache)(BlockDriverState *bs); 134 135 /* 136 * Flushes all data that was already written to the OS all the way down to 137 * the disk (for example raw-posix calls fsync()). 138 */ 139 int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs); 140 141 /* 142 * Flushes all internal caches to the OS. The data may still sit in a 143 * writeback cache of the host OS, but it will survive a crash of the qemu 144 * process. 145 */ 146 int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs); 147 148 const char *protocol_name; 149 int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset); 150 int64_t (*bdrv_getlength)(BlockDriverState *bs); 151 int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs); 152 int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num, 153 const uint8_t *buf, int nb_sectors); 154 155 int (*bdrv_snapshot_create)(BlockDriverState *bs, 156 QEMUSnapshotInfo *sn_info); 157 int (*bdrv_snapshot_goto)(BlockDriverState *bs, 158 const char *snapshot_id); 159 int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id); 160 int (*bdrv_snapshot_list)(BlockDriverState *bs, 161 QEMUSnapshotInfo **psn_info); 162 int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, 163 const char *snapshot_name); 164 int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi); 165 166 int (*bdrv_save_vmstate)(BlockDriverState *bs, QEMUIOVector *qiov, 167 int64_t pos); 168 int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf, 169 int64_t pos, int size); 170 171 int (*bdrv_change_backing_file)(BlockDriverState *bs, 172 const char *backing_file, const char *backing_fmt); 173 174 /* removable device specific */ 175 int (*bdrv_is_inserted)(BlockDriverState *bs); 176 int (*bdrv_media_changed)(BlockDriverState *bs); 177 void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag); 178 void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked); 179 180 /* to control generic scsi devices */ 181 int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf); 182 BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs, 183 unsigned long int req, void *buf, 184 BlockDriverCompletionFunc *cb, void *opaque); 185 186 /* List of options for creating images, terminated by name == NULL */ 187 QEMUOptionParameter *create_options; 188 189 190 /* 191 * Returns 0 for completed check, -errno for internal errors. 192 * The check results are stored in result. 193 */ 194 int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result, 195 BdrvCheckMode fix); 196 197 void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event); 198 199 /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */ 200 int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event, 201 const char *tag); 202 int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag); 203 bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag); 204 205 /* 206 * Returns 1 if newly created images are guaranteed to contain only 207 * zeros, 0 otherwise. 208 */ 209 int (*bdrv_has_zero_init)(BlockDriverState *bs); 210 211 QLIST_ENTRY(BlockDriver) list; 212 }; 213 214 /* 215 * Note: the function bdrv_append() copies and swaps contents of 216 * BlockDriverStates, so if you add new fields to this struct, please 217 * inspect bdrv_append() to determine if the new fields need to be 218 * copied as well. 219 */ 220 struct BlockDriverState { 221 int64_t total_sectors; /* if we are reading a disk image, give its 222 size in sectors */ 223 int read_only; /* if true, the media is read only */ 224 int open_flags; /* flags used to open the file, re-used for re-open */ 225 int encrypted; /* if true, the media is encrypted */ 226 int valid_key; /* if true, a valid encryption key has been set */ 227 int sg; /* if true, the device is a /dev/sg* */ 228 int copy_on_read; /* if true, copy read backing sectors into image 229 note this is a reference count */ 230 231 BlockDriver *drv; /* NULL means no media */ 232 void *opaque; 233 234 void *dev; /* attached device model, if any */ 235 /* TODO change to DeviceState when all users are qdevified */ 236 const BlockDevOps *dev_ops; 237 void *dev_opaque; 238 239 char filename[1024]; 240 char backing_file[1024]; /* if non zero, the image is a diff of 241 this file image */ 242 char backing_format[16]; /* if non-zero and backing_file exists */ 243 int is_temporary; 244 245 BlockDriverState *backing_hd; 246 BlockDriverState *file; 247 248 NotifierList close_notifiers; 249 250 /* number of in-flight copy-on-read requests */ 251 unsigned int copy_on_read_in_flight; 252 253 /* the time for latest disk I/O */ 254 int64_t slice_start; 255 int64_t slice_end; 256 BlockIOLimit io_limits; 257 BlockIOBaseValue slice_submitted; 258 CoQueue throttled_reqs; 259 QEMUTimer *block_timer; 260 bool io_limits_enabled; 261 262 /* I/O stats (display with "info blockstats"). */ 263 uint64_t nr_bytes[BDRV_MAX_IOTYPE]; 264 uint64_t nr_ops[BDRV_MAX_IOTYPE]; 265 uint64_t total_time_ns[BDRV_MAX_IOTYPE]; 266 uint64_t wr_highest_sector; 267 268 /* Whether the disk can expand beyond total_sectors */ 269 int growable; 270 271 /* the memory alignment required for the buffers handled by this driver */ 272 int buffer_alignment; 273 274 /* do we need to tell the quest if we have a volatile write cache? */ 275 int enable_write_cache; 276 277 /* NOTE: the following infos are only hints for real hardware 278 drivers. They are not used by the block driver */ 279 BlockdevOnError on_read_error, on_write_error; 280 bool iostatus_enabled; 281 BlockDeviceIoStatus iostatus; 282 char device_name[32]; 283 HBitmap *dirty_bitmap; 284 int in_use; /* users other than guest access, eg. block migration */ 285 QTAILQ_ENTRY(BlockDriverState) list; 286 287 QLIST_HEAD(, BdrvTrackedRequest) tracked_requests; 288 289 /* long-running background operation */ 290 BlockJob *job; 291 292 QDict *options; 293 }; 294 295 int get_tmp_filename(char *filename, int size); 296 297 void bdrv_set_io_limits(BlockDriverState *bs, 298 BlockIOLimit *io_limits); 299 300 /** 301 * bdrv_get_aio_context: 302 * 303 * Returns: the currently bound #AioContext 304 */ 305 AioContext *bdrv_get_aio_context(BlockDriverState *bs); 306 307 #ifdef _WIN32 308 int is_windows_drive(const char *filename); 309 #endif 310 void bdrv_emit_qmp_error_event(const BlockDriverState *bdrv, 311 enum MonitorEvent ev, 312 BlockErrorAction action, bool is_read); 313 314 /** 315 * stream_start: 316 * @bs: Block device to operate on. 317 * @base: Block device that will become the new base, or %NULL to 318 * flatten the whole backing file chain onto @bs. 319 * @base_id: The file name that will be written to @bs as the new 320 * backing file if the job completes. Ignored if @base is %NULL. 321 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 322 * @on_error: The action to take upon error. 323 * @cb: Completion function for the job. 324 * @opaque: Opaque pointer value passed to @cb. 325 * @errp: Error object. 326 * 327 * Start a streaming operation on @bs. Clusters that are unallocated 328 * in @bs, but allocated in any image between @base and @bs (both 329 * exclusive) will be written to @bs. At the end of a successful 330 * streaming job, the backing file of @bs will be changed to 331 * @base_id in the written image and to @base in the live BlockDriverState. 332 */ 333 void stream_start(BlockDriverState *bs, BlockDriverState *base, 334 const char *base_id, int64_t speed, BlockdevOnError on_error, 335 BlockDriverCompletionFunc *cb, 336 void *opaque, Error **errp); 337 338 /** 339 * commit_start: 340 * @bs: Top Block device 341 * @base: Block device that will be written into, and become the new top 342 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 343 * @on_error: The action to take upon error. 344 * @cb: Completion function for the job. 345 * @opaque: Opaque pointer value passed to @cb. 346 * @errp: Error object. 347 * 348 */ 349 void commit_start(BlockDriverState *bs, BlockDriverState *base, 350 BlockDriverState *top, int64_t speed, 351 BlockdevOnError on_error, BlockDriverCompletionFunc *cb, 352 void *opaque, Error **errp); 353 354 /* 355 * mirror_start: 356 * @bs: Block device to operate on. 357 * @target: Block device to write to. 358 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 359 * @granularity: The chosen granularity for the dirty bitmap. 360 * @buf_size: The amount of data that can be in flight at one time. 361 * @mode: Whether to collapse all images in the chain to the target. 362 * @on_source_error: The action to take upon error reading from the source. 363 * @on_target_error: The action to take upon error writing to the target. 364 * @cb: Completion function for the job. 365 * @opaque: Opaque pointer value passed to @cb. 366 * @errp: Error object. 367 * 368 * Start a mirroring operation on @bs. Clusters that are allocated 369 * in @bs will be written to @bs until the job is cancelled or 370 * manually completed. At the end of a successful mirroring job, 371 * @bs will be switched to read from @target. 372 */ 373 void mirror_start(BlockDriverState *bs, BlockDriverState *target, 374 int64_t speed, int64_t granularity, int64_t buf_size, 375 MirrorSyncMode mode, BlockdevOnError on_source_error, 376 BlockdevOnError on_target_error, 377 BlockDriverCompletionFunc *cb, 378 void *opaque, Error **errp); 379 380 #endif /* BLOCK_INT_H */ 381