block_int-global-state.h (15143B)
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 25 #ifndef BLOCK_INT_GLOBAL_STATE_H 26 #define BLOCK_INT_GLOBAL_STATE_H 27 28 #include "block_int-common.h" 29 30 /* 31 * Global state (GS) API. These functions run under the BQL. 32 * 33 * See include/block/block-global-state.h for more information about 34 * the GS API. 35 */ 36 37 /** 38 * stream_start: 39 * @job_id: The id of the newly-created job, or %NULL to use the 40 * device name of @bs. 41 * @bs: Block device to operate on. 42 * @base: Block device that will become the new base, or %NULL to 43 * flatten the whole backing file chain onto @bs. 44 * @backing_file_str: The file name that will be written to @bs as the 45 * the new backing file if the job completes. Ignored if @base is %NULL. 46 * @creation_flags: Flags that control the behavior of the Job lifetime. 47 * See @BlockJobCreateFlags 48 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 49 * @on_error: The action to take upon error. 50 * @filter_node_name: The node name that should be assigned to the filter 51 * driver that the stream job inserts into the graph above 52 * @bs. NULL means that a node name should be autogenerated. 53 * @errp: Error object. 54 * 55 * Start a streaming operation on @bs. Clusters that are unallocated 56 * in @bs, but allocated in any image between @base and @bs (both 57 * exclusive) will be written to @bs. At the end of a successful 58 * streaming job, the backing file of @bs will be changed to 59 * @backing_file_str in the written image and to @base in the live 60 * BlockDriverState. 61 */ 62 void stream_start(const char *job_id, BlockDriverState *bs, 63 BlockDriverState *base, const char *backing_file_str, 64 BlockDriverState *bottom, 65 int creation_flags, int64_t speed, 66 BlockdevOnError on_error, 67 const char *filter_node_name, 68 Error **errp); 69 70 /** 71 * commit_start: 72 * @job_id: The id of the newly-created job, or %NULL to use the 73 * device name of @bs. 74 * @bs: Active block device. 75 * @top: Top block device to be committed. 76 * @base: Block device that will be written into, and become the new top. 77 * @creation_flags: Flags that control the behavior of the Job lifetime. 78 * See @BlockJobCreateFlags 79 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 80 * @on_error: The action to take upon error. 81 * @backing_file_str: String to use as the backing file in @top's overlay 82 * @filter_node_name: The node name that should be assigned to the filter 83 * driver that the commit job inserts into the graph above @top. NULL means 84 * that a node name should be autogenerated. 85 * @errp: Error object. 86 * 87 */ 88 void commit_start(const char *job_id, BlockDriverState *bs, 89 BlockDriverState *base, BlockDriverState *top, 90 int creation_flags, int64_t speed, 91 BlockdevOnError on_error, const char *backing_file_str, 92 const char *filter_node_name, Error **errp); 93 /** 94 * commit_active_start: 95 * @job_id: The id of the newly-created job, or %NULL to use the 96 * device name of @bs. 97 * @bs: Active block device to be committed. 98 * @base: Block device that will be written into, and become the new top. 99 * @creation_flags: Flags that control the behavior of the Job lifetime. 100 * See @BlockJobCreateFlags 101 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 102 * @on_error: The action to take upon error. 103 * @filter_node_name: The node name that should be assigned to the filter 104 * driver that the commit job inserts into the graph above @bs. NULL means that 105 * a node name should be autogenerated. 106 * @cb: Completion function for the job. 107 * @opaque: Opaque pointer value passed to @cb. 108 * @auto_complete: Auto complete the job. 109 * @errp: Error object. 110 * 111 */ 112 BlockJob *commit_active_start(const char *job_id, BlockDriverState *bs, 113 BlockDriverState *base, int creation_flags, 114 int64_t speed, BlockdevOnError on_error, 115 const char *filter_node_name, 116 BlockCompletionFunc *cb, void *opaque, 117 bool auto_complete, Error **errp); 118 /* 119 * mirror_start: 120 * @job_id: The id of the newly-created job, or %NULL to use the 121 * device name of @bs. 122 * @bs: Block device to operate on. 123 * @target: Block device to write to. 124 * @replaces: Block graph node name to replace once the mirror is done. Can 125 * only be used when full mirroring is selected. 126 * @creation_flags: Flags that control the behavior of the Job lifetime. 127 * See @BlockJobCreateFlags 128 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 129 * @granularity: The chosen granularity for the dirty bitmap. 130 * @buf_size: The amount of data that can be in flight at one time. 131 * @mode: Whether to collapse all images in the chain to the target. 132 * @backing_mode: How to establish the target's backing chain after completion. 133 * @zero_target: Whether the target should be explicitly zero-initialized 134 * @on_source_error: The action to take upon error reading from the source. 135 * @on_target_error: The action to take upon error writing to the target. 136 * @unmap: Whether to unmap target where source sectors only contain zeroes. 137 * @filter_node_name: The node name that should be assigned to the filter 138 * driver that the mirror job inserts into the graph above @bs. NULL means that 139 * a node name should be autogenerated. 140 * @copy_mode: When to trigger writes to the target. 141 * @errp: Error object. 142 * 143 * Start a mirroring operation on @bs. Clusters that are allocated 144 * in @bs will be written to @target until the job is cancelled or 145 * manually completed. At the end of a successful mirroring job, 146 * @bs will be switched to read from @target. 147 */ 148 void mirror_start(const char *job_id, BlockDriverState *bs, 149 BlockDriverState *target, const char *replaces, 150 int creation_flags, int64_t speed, 151 uint32_t granularity, int64_t buf_size, 152 MirrorSyncMode mode, BlockMirrorBackingMode backing_mode, 153 bool zero_target, 154 BlockdevOnError on_source_error, 155 BlockdevOnError on_target_error, 156 bool unmap, const char *filter_node_name, 157 MirrorCopyMode copy_mode, Error **errp); 158 159 /* 160 * backup_job_create: 161 * @job_id: The id of the newly-created job, or %NULL to use the 162 * device name of @bs. 163 * @bs: Block device to operate on. 164 * @target: Block device to write to. 165 * @speed: The maximum speed, in bytes per second, or 0 for unlimited. 166 * @sync_mode: What parts of the disk image should be copied to the destination. 167 * @sync_bitmap: The dirty bitmap if sync_mode is 'bitmap' or 'incremental' 168 * @bitmap_mode: The bitmap synchronization policy to use. 169 * @perf: Performance options. All actual fields assumed to be present, 170 * all ".has_*" fields are ignored. 171 * @on_source_error: The action to take upon error reading from the source. 172 * @on_target_error: The action to take upon error writing to the target. 173 * @creation_flags: Flags that control the behavior of the Job lifetime. 174 * See @BlockJobCreateFlags 175 * @cb: Completion function for the job. 176 * @opaque: Opaque pointer value passed to @cb. 177 * @txn: Transaction that this job is part of (may be NULL). 178 * 179 * Create a backup operation on @bs. Clusters in @bs are written to @target 180 * until the job is cancelled or manually completed. 181 */ 182 BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs, 183 BlockDriverState *target, int64_t speed, 184 MirrorSyncMode sync_mode, 185 BdrvDirtyBitmap *sync_bitmap, 186 BitmapSyncMode bitmap_mode, 187 bool compress, 188 const char *filter_node_name, 189 BackupPerf *perf, 190 BlockdevOnError on_source_error, 191 BlockdevOnError on_target_error, 192 int creation_flags, 193 BlockCompletionFunc *cb, void *opaque, 194 JobTxn *txn, Error **errp); 195 196 BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs, 197 const char *child_name, 198 const BdrvChildClass *child_class, 199 BdrvChildRole child_role, 200 uint64_t perm, uint64_t shared_perm, 201 void *opaque, Error **errp); 202 void bdrv_root_unref_child(BdrvChild *child); 203 204 void bdrv_get_cumulative_perm(BlockDriverState *bs, uint64_t *perm, 205 uint64_t *shared_perm); 206 207 /** 208 * Sets a BdrvChild's permissions. Avoid if the parent is a BDS; use 209 * bdrv_child_refresh_perms() instead and make the parent's 210 * .bdrv_child_perm() implementation return the correct values. 211 */ 212 int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared, 213 Error **errp); 214 215 /** 216 * Calls bs->drv->bdrv_child_perm() and updates the child's permission 217 * masks with the result. 218 * Drivers should invoke this function whenever an event occurs that 219 * makes their .bdrv_child_perm() implementation return different 220 * values than before, but which will not result in the block layer 221 * automatically refreshing the permissions. 222 */ 223 int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp); 224 225 bool bdrv_recurse_can_replace(BlockDriverState *bs, 226 BlockDriverState *to_replace); 227 228 /* 229 * Default implementation for BlockDriver.bdrv_child_perm() that can 230 * be used by block filters and image formats, as long as they use the 231 * child_of_bds child class and set an appropriate BdrvChildRole. 232 */ 233 void bdrv_default_perms(BlockDriverState *bs, BdrvChild *c, 234 BdrvChildRole role, BlockReopenQueue *reopen_queue, 235 uint64_t perm, uint64_t shared, 236 uint64_t *nperm, uint64_t *nshared); 237 238 void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp); 239 bool blk_dev_has_removable_media(BlockBackend *blk); 240 void blk_dev_eject_request(BlockBackend *blk, bool force); 241 bool blk_dev_is_medium_locked(BlockBackend *blk); 242 243 void bdrv_restore_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *backup); 244 245 void bdrv_set_monitor_owned(BlockDriverState *bs); 246 247 void blockdev_close_all_bdrv_states(void); 248 249 BlockDriverState *bds_tree_init(QDict *bs_opts, Error **errp); 250 251 /** 252 * Simple implementation of bdrv_co_create_opts for protocol drivers 253 * which only support creation via opening a file 254 * (usually existing raw storage device) 255 */ 256 int coroutine_fn bdrv_co_create_opts_simple(BlockDriver *drv, 257 const char *filename, 258 QemuOpts *opts, 259 Error **errp); 260 261 BdrvDirtyBitmap *block_dirty_bitmap_lookup(const char *node, 262 const char *name, 263 BlockDriverState **pbs, 264 Error **errp); 265 BdrvDirtyBitmap *block_dirty_bitmap_merge(const char *node, const char *target, 266 BlockDirtyBitmapOrStrList *bms, 267 HBitmap **backup, Error **errp); 268 BdrvDirtyBitmap *block_dirty_bitmap_remove(const char *node, const char *name, 269 bool release, 270 BlockDriverState **bitmap_bs, 271 Error **errp); 272 273 274 BlockDriverState *bdrv_skip_implicit_filters(BlockDriverState *bs); 275 276 /** 277 * bdrv_add_aio_context_notifier: 278 * 279 * If a long-running job intends to be always run in the same AioContext as a 280 * certain BDS, it may use this function to be notified of changes regarding the 281 * association of the BDS to an AioContext. 282 * 283 * attached_aio_context() is called after the target BDS has been attached to a 284 * new AioContext; detach_aio_context() is called before the target BDS is being 285 * detached from its old AioContext. 286 */ 287 void bdrv_add_aio_context_notifier(BlockDriverState *bs, 288 void (*attached_aio_context)(AioContext *new_context, void *opaque), 289 void (*detach_aio_context)(void *opaque), void *opaque); 290 291 /** 292 * bdrv_remove_aio_context_notifier: 293 * 294 * Unsubscribe of change notifications regarding the BDS's AioContext. The 295 * parameters given here have to be the same as those given to 296 * bdrv_add_aio_context_notifier(). 297 */ 298 void bdrv_remove_aio_context_notifier(BlockDriverState *bs, 299 void (*aio_context_attached)(AioContext *, 300 void *), 301 void (*aio_context_detached)(void *), 302 void *opaque); 303 304 /** 305 * End all quiescent sections started by bdrv_drain_all_begin(). This is 306 * needed when deleting a BDS before bdrv_drain_all_end() is called. 307 * 308 * NOTE: this is an internal helper for bdrv_close() *only*. No one else 309 * should call it. 310 */ 311 void bdrv_drain_all_end_quiesce(BlockDriverState *bs); 312 313 /** 314 * Make sure that the function is running under both drain and BQL. 315 * The latter protects from concurrent writings 316 * from the GS API, while the former prevents concurrent reads 317 * from I/O. 318 */ 319 static inline void assert_bdrv_graph_writable(BlockDriverState *bs) 320 { 321 /* 322 * TODO: this function is incomplete. Because the users of this 323 * assert lack the necessary drains, check only for BQL. 324 * Once the necessary drains are added, 325 * assert also for qatomic_read(&bs->quiesce_counter) > 0 326 */ 327 assert(qemu_in_main_thread()); 328 } 329 330 #endif /* BLOCK_INT_GLOBAL_STATE_H */