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 /* For handling image reopen for split or non-split files */ 80 int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state, 81 BlockReopenQueue *queue, Error **errp); 82 void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state); 83 void (*bdrv_reopen_abort)(BDRVReopenState *reopen_state); 84 85 int (*bdrv_open)(BlockDriverState *bs, int flags); 86 int (*bdrv_file_open)(BlockDriverState *bs, const char *filename, int flags); 87 int (*bdrv_read)(BlockDriverState *bs, int64_t sector_num, 88 uint8_t *buf, int nb_sectors); 89 int (*bdrv_write)(BlockDriverState *bs, int64_t sector_num, 90 const uint8_t *buf, int nb_sectors); 91 void (*bdrv_close)(BlockDriverState *bs); 92 void (*bdrv_rebind)(BlockDriverState *bs); 93 int (*bdrv_create)(const char *filename, QEMUOptionParameter *options); 94 int (*bdrv_set_key)(BlockDriverState *bs, const char *key); 95 int (*bdrv_make_empty)(BlockDriverState *bs); 96 /* aio */ 97 BlockDriverAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs, 98 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 99 BlockDriverCompletionFunc *cb, void *opaque); 100 BlockDriverAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs, 101 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, 102 BlockDriverCompletionFunc *cb, void *opaque); 103 BlockDriverAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs, 104 BlockDriverCompletionFunc *cb, void *opaque); 105 BlockDriverAIOCB *(*bdrv_aio_discard)(BlockDriverState *bs, 106 int64_t sector_num, int nb_sectors, 107 BlockDriverCompletionFunc *cb, void *opaque); 108 109 int coroutine_fn (*bdrv_co_readv)(BlockDriverState *bs, 110 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); 111 int coroutine_fn (*bdrv_co_writev)(BlockDriverState *bs, 112 int64_t sector_num, int nb_sectors, QEMUIOVector *qiov); 113 /* 114 * Efficiently zero a region of the disk image. Typically an image format 115 * would use a compact metadata representation to implement this. This 116 * function pointer may be NULL and .bdrv_co_writev() will be called 117 * instead. 118 */ 119 int coroutine_fn (*bdrv_co_write_zeroes)(BlockDriverState *bs, 120 int64_t sector_num, int nb_sectors); 121 int coroutine_fn (*bdrv_co_discard)(BlockDriverState *bs, 122 int64_t sector_num, int nb_sectors); 123 int coroutine_fn (*bdrv_co_is_allocated)(BlockDriverState *bs, 124 int64_t sector_num, int nb_sectors, int *pnum); 125 126 /* 127 * Invalidate any cached meta-data. 128 */ 129 void (*bdrv_invalidate_cache)(BlockDriverState *bs); 130 131 /* 132 * Flushes all data that was already written to the OS all the way down to 133 * the disk (for example raw-posix calls fsync()). 134 */ 135 int coroutine_fn (*bdrv_co_flush_to_disk)(BlockDriverState *bs); 136 137 /* 138 * Flushes all internal caches to the OS. The data may still sit in a 139 * writeback cache of the host OS, but it will survive a crash of the qemu 140 * process. 141 */ 142 int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs); 143 144 const char *protocol_name; 145 int (*bdrv_truncate)(BlockDriverState *bs, int64_t offset); 146 int64_t (*bdrv_getlength)(BlockDriverState *bs); 147 int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs); 148 int (*bdrv_write_compressed)(BlockDriverState *bs, int64_t sector_num, 149 const uint8_t *buf, int nb_sectors); 150 151 int (*bdrv_snapshot_create)(BlockDriverState *bs, 152 QEMUSnapshotInfo *sn_info); 153 int (*bdrv_snapshot_goto)(BlockDriverState *bs, 154 const char *snapshot_id); 155 int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id); 156 int (*bdrv_snapshot_list)(BlockDriverState *bs, 157 QEMUSnapshotInfo **psn_info); 158 int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, 159 const char *snapshot_name); 160 int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi); 161 162 int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf, 163 int64_t pos, int size); 164 int (*bdrv_load_vmstate)(BlockDriverState *bs, uint8_t *buf, 165 int64_t pos, int size); 166 167 int (*bdrv_change_backing_file)(BlockDriverState *bs, 168 const char *backing_file, const char *backing_fmt); 169 170 /* removable device specific */ 171 int (*bdrv_is_inserted)(BlockDriverState *bs); 172 int (*bdrv_media_changed)(BlockDriverState *bs); 173 void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag); 174 void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked); 175 176 /* to control generic scsi devices */ 177 int (*bdrv_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf); 178 BlockDriverAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs, 179 unsigned long int req, void *buf, 180 BlockDriverCompletionFunc *cb, void *opaque); 181 182 /* List of options for creating images, terminated by name == NULL */ 183 QEMUOptionParameter *create_options; 184 185 186 /* 187 * Returns 0 for completed check, -errno for internal errors. 188 * The check results are stored in result. 189 */ 190 int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result, 191 BdrvCheckMode fix); 192 193 void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event); 194 195 /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */ 196 int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event, 197 const char *tag); 198 int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag); 199 bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag); 200 201 /* 202 * Returns 1 if newly created images are guaranteed to contain only 203 * zeros, 0 otherwise. 204 */ 205 int (*bdrv_has_zero_init)(BlockDriverState *bs); 206 207 QLIST_ENTRY(BlockDriver) list; 208 }; 209 210 /* 211 * Note: the function bdrv_append() copies and swaps contents of 212 * BlockDriverStates, so if you add new fields to this struct, please 213 * inspect bdrv_append() to determine if the new fields need to be 214 * copied as well. 215 */ 216 struct BlockDriverState { 217 int64_t total_sectors; /* if we are reading a disk image, give its 218 size in sectors */ 219 int read_only; /* if true, the media is read only */ 220 int open_flags; /* flags used to open the file, re-used for re-open */ 221 int encrypted; /* if true, the media is encrypted */ 222 int valid_key; /* if true, a valid encryption key has been set */ 223 int sg; /* if true, the device is a /dev/sg* */ 224 int copy_on_read; /* if true, copy read backing sectors into image 225 note this is a reference count */ 226 227 BlockDriver *drv; /* NULL means no media */ 228 void *opaque; 229 230 void *dev; /* attached device model, if any */ 231 /* TODO change to DeviceState when all users are qdevified */ 232 const BlockDevOps *dev_ops; 233 void *dev_opaque; 234 235 char filename[1024]; 236 char backing_file[1024]; /* if non zero, the image is a diff of 237 this file image */ 238 char backing_format[16]; /* if non-zero and backing_file exists */ 239 int is_temporary; 240 241 BlockDriverState *backing_hd; 242 BlockDriverState *file; 243 244 NotifierList close_notifiers; 245 246 /* number of in-flight copy-on-read requests */ 247 unsigned int copy_on_read_in_flight; 248 249 /* the time for latest disk I/O */ 250 int64_t slice_time; 251 int64_t slice_start; 252 int64_t slice_end; 253 BlockIOLimit io_limits; 254 BlockIOBaseValue io_base; 255 CoQueue throttled_reqs; 256 QEMUTimer *block_timer; 257 bool io_limits_enabled; 258 259 /* I/O stats (display with "info blockstats"). */ 260 uint64_t nr_bytes[BDRV_MAX_IOTYPE]; 261 uint64_t nr_ops[BDRV_MAX_IOTYPE]; 262 uint64_t total_time_ns[BDRV_MAX_IOTYPE]; 263 uint64_t wr_highest_sector; 264 265 /* Whether the disk can expand beyond total_sectors */ 266 int growable; 267 268 /* the memory alignment required for the buffers handled by this driver */ 269 int buffer_alignment; 270 271 /* do we need to tell the quest if we have a volatile write cache? */ 272 int enable_write_cache; 273 274 /* NOTE: the following infos are only hints for real hardware 275 drivers. They are not used by the block driver */ 276 BlockdevOnError on_read_error, on_write_error; 277 bool iostatus_enabled; 278 BlockDeviceIoStatus iostatus; 279 char device_name[32]; 280 HBitmap *dirty_bitmap; 281 int in_use; /* users other than guest access, eg. block migration */ 282 QTAILQ_ENTRY(BlockDriverState) list; 283 284 QLIST_HEAD(, BdrvTrackedRequest) tracked_requests; 285 286 /* long-running background operation */ 287 BlockJob *job; 288 289 }; 290 291 int get_tmp_filename(char *filename, int size); 292 293 void bdrv_set_io_limits(BlockDriverState *bs, 294 BlockIOLimit *io_limits); 295 296 #ifdef _WIN32 297 int is_windows_drive(const char *filename); 298 #endif 299 void bdrv_emit_qmp_error_event(const BlockDriverState *bdrv, 300 enum MonitorEvent ev, 301 BlockErrorAction action, bool is_read); 302 303 /** 304 * stream_start: 305 * @bs: Block device to operate on. 306 * @base: Block device that will become the new base, or %NULL to 307 * flatten the whole backing file chain onto @bs. 308 * @base_id: The file name that will be written to @bs as the new 309 * backing file if the job completes. Ignored if @base is %NULL. 310 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 311 * @on_error: The action to take upon error. 312 * @cb: Completion function for the job. 313 * @opaque: Opaque pointer value passed to @cb. 314 * @errp: Error object. 315 * 316 * Start a streaming operation on @bs. Clusters that are unallocated 317 * in @bs, but allocated in any image between @base and @bs (both 318 * exclusive) will be written to @bs. At the end of a successful 319 * streaming job, the backing file of @bs will be changed to 320 * @base_id in the written image and to @base in the live BlockDriverState. 321 */ 322 void stream_start(BlockDriverState *bs, BlockDriverState *base, 323 const char *base_id, int64_t speed, BlockdevOnError on_error, 324 BlockDriverCompletionFunc *cb, 325 void *opaque, Error **errp); 326 327 /** 328 * commit_start: 329 * @bs: Top Block device 330 * @base: Block device that will be written into, and become the new top 331 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 332 * @on_error: The action to take upon error. 333 * @cb: Completion function for the job. 334 * @opaque: Opaque pointer value passed to @cb. 335 * @errp: Error object. 336 * 337 */ 338 void commit_start(BlockDriverState *bs, BlockDriverState *base, 339 BlockDriverState *top, int64_t speed, 340 BlockdevOnError on_error, BlockDriverCompletionFunc *cb, 341 void *opaque, Error **errp); 342 343 /* 344 * mirror_start: 345 * @bs: Block device to operate on. 346 * @target: Block device to write to. 347 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 348 * @granularity: The chosen granularity for the dirty bitmap. 349 * @buf_size: The amount of data that can be in flight at one time. 350 * @mode: Whether to collapse all images in the chain to the target. 351 * @on_source_error: The action to take upon error reading from the source. 352 * @on_target_error: The action to take upon error writing to the target. 353 * @cb: Completion function for the job. 354 * @opaque: Opaque pointer value passed to @cb. 355 * @errp: Error object. 356 * 357 * Start a mirroring operation on @bs. Clusters that are allocated 358 * in @bs will be written to @bs until the job is cancelled or 359 * manually completed. At the end of a successful mirroring job, 360 * @bs will be switched to read from @target. 361 */ 362 void mirror_start(BlockDriverState *bs, BlockDriverState *target, 363 int64_t speed, int64_t granularity, int64_t buf_size, 364 MirrorSyncMode mode, BlockdevOnError on_source_error, 365 BlockdevOnError on_target_error, 366 BlockDriverCompletionFunc *cb, 367 void *opaque, Error **errp); 368 369 #endif /* BLOCK_INT_H */ 370