include/block/block_int-global-state.h

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