include/block/block_int-global-state.h - qemu - Git at Google

 /*
  * QEMU System Emulator block driver
  *
  * Copyright (c) 2003 Fabrice Bellard
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */

 #ifndef BLOCK_INT_GLOBAL_STATE_H
 #define BLOCK_INT_GLOBAL_STATE_H

 #include "block_int-common.h"

 /*
  * Global state (GS) API. These functions run under the BQL.
  *
  * See include/block/block-global-state.h for more information about
  * the GS API.
  */

 /**
  * stream_start:
  * @job_id: The id of the newly-created job, or %NULL to use the
  * device name of @bs.
  * @bs: Block device to operate on.
  * @base: Block device that will become the new base, or %NULL to
  * flatten the whole backing file chain onto @bs.
  * @backing_file_str: The file name that will be written to @bs as the
  * the new backing file if the job completes. Ignored if @base is %NULL.
  * @creation_flags: Flags that control the behavior of the Job lifetime.
  *                  See @BlockJobCreateFlags
  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
  * @on_error: The action to take upon error.
  * @filter_node_name: The node name that should be assigned to the filter
  *                    driver that the stream job inserts into the graph above
  *                    @bs. NULL means that a node name should be autogenerated.
  * @errp: Error object.
  *
  * Start a streaming operation on @bs.  Clusters that are unallocated
  * in @bs, but allocated in any image between @base and @bs (both
  * exclusive) will be written to @bs.  At the end of a successful
  * streaming job, the backing file of @bs will be changed to
  * @backing_file_str in the written image and to @base in the live
  * BlockDriverState.
  */
 void stream_start(const char *job_id, BlockDriverState *bs,
                   BlockDriverState *base, const char *backing_file_str,
                   BlockDriverState *bottom,
                   int creation_flags, int64_t speed,
                   BlockdevOnError on_error,
                   const char *filter_node_name,
                   Error **errp);

 /**
  * commit_start:
  * @job_id: The id of the newly-created job, or %NULL to use the
  * device name of @bs.
  * @bs: Active block device.
  * @top: Top block device to be committed.
  * @base: Block device that will be written into, and become the new top.
  * @creation_flags: Flags that control the behavior of the Job lifetime.
  *                  See @BlockJobCreateFlags
  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
  * @on_error: The action to take upon error.
  * @backing_file_str: String to use as the backing file in @top's overlay
  * @filter_node_name: The node name that should be assigned to the filter
  * driver that the commit job inserts into the graph above @top. NULL means
  * that a node name should be autogenerated.
  * @errp: Error object.
  *
  */
 void commit_start(const char *job_id, BlockDriverState *bs,
                   BlockDriverState *base, BlockDriverState *top,
                   int creation_flags, int64_t speed,
                   BlockdevOnError on_error, const char *backing_file_str,
                   const char *filter_node_name, Error **errp);
 /**
  * commit_active_start:
  * @job_id: The id of the newly-created job, or %NULL to use the
  * device name of @bs.
  * @bs: Active block device to be committed.
  * @base: Block device that will be written into, and become the new top.
  * @creation_flags: Flags that control the behavior of the Job lifetime.
  *                  See @BlockJobCreateFlags
  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
  * @on_error: The action to take upon error.
  * @filter_node_name: The node name that should be assigned to the filter
  * driver that the commit job inserts into the graph above @bs. NULL means that
  * a node name should be autogenerated.
  * @cb: Completion function for the job.
  * @opaque: Opaque pointer value passed to @cb.
  * @auto_complete: Auto complete the job.
  * @errp: Error object.
  *
  */
 BlockJob *commit_active_start(const char *job_id, BlockDriverState *bs,
                               BlockDriverState *base, int creation_flags,
                               int64_t speed, BlockdevOnError on_error,
                               const char *filter_node_name,
                               BlockCompletionFunc *cb, void *opaque,
                               bool auto_complete, Error **errp);
 /*
  * mirror_start:
  * @job_id: The id of the newly-created job, or %NULL to use the
  * device name of @bs.
  * @bs: Block device to operate on.
  * @target: Block device to write to.
  * @replaces: Block graph node name to replace once the mirror is done. Can
  *            only be used when full mirroring is selected.
  * @creation_flags: Flags that control the behavior of the Job lifetime.
  *                  See @BlockJobCreateFlags
  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
  * @granularity: The chosen granularity for the dirty bitmap.
  * @buf_size: The amount of data that can be in flight at one time.
  * @mode: Whether to collapse all images in the chain to the target.
  * @backing_mode: How to establish the target's backing chain after completion.
  * @zero_target: Whether the target should be explicitly zero-initialized
  * @on_source_error: The action to take upon error reading from the source.
  * @on_target_error: The action to take upon error writing to the target.
  * @unmap: Whether to unmap target where source sectors only contain zeroes.
  * @filter_node_name: The node name that should be assigned to the filter
  * driver that the mirror job inserts into the graph above @bs. NULL means that
  * a node name should be autogenerated.
  * @copy_mode: When to trigger writes to the target.
  * @errp: Error object.
  *
  * Start a mirroring operation on @bs.  Clusters that are allocated
  * in @bs will be written to @target until the job is cancelled or
  * manually completed.  At the end of a successful mirroring job,
  * @bs will be switched to read from @target.
  */
 void mirror_start(const char *job_id, BlockDriverState *bs,
                   BlockDriverState *target, const char *replaces,
                   int creation_flags, int64_t speed,
                   uint32_t granularity, int64_t buf_size,
                   MirrorSyncMode mode, BlockMirrorBackingMode backing_mode,
                   bool zero_target,
                   BlockdevOnError on_source_error,
                   BlockdevOnError on_target_error,
                   bool unmap, const char *filter_node_name,
                   MirrorCopyMode copy_mode, Error **errp);

 /*
  * backup_job_create:
  * @job_id: The id of the newly-created job, or %NULL to use the
  * device name of @bs.
  * @bs: Block device to operate on.
  * @target: Block device to write to.
  * @speed: The maximum speed, in bytes per second, or 0 for unlimited.
  * @sync_mode: What parts of the disk image should be copied to the destination.
  * @sync_bitmap: The dirty bitmap if sync_mode is 'bitmap' or 'incremental'
  * @bitmap_mode: The bitmap synchronization policy to use.
  * @perf: Performance options. All actual fields assumed to be present,
  *        all ".has_*" fields are ignored.
  * @on_source_error: The action to take upon error reading from the source.
  * @on_target_error: The action to take upon error writing to the target.
  * @creation_flags: Flags that control the behavior of the Job lifetime.
  *                  See @BlockJobCreateFlags
  * @cb: Completion function for the job.
  * @opaque: Opaque pointer value passed to @cb.
  * @txn: Transaction that this job is part of (may be NULL).
  *
  * Create a backup operation on @bs.  Clusters in @bs are written to @target
  * until the job is cancelled or manually completed.
  */
 BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
                             BlockDriverState *target, int64_t speed,
                             MirrorSyncMode sync_mode,
                             BdrvDirtyBitmap *sync_bitmap,
                             BitmapSyncMode bitmap_mode,
                             bool compress,
                             const char *filter_node_name,
                             BackupPerf *perf,
                             BlockdevOnError on_source_error,
                             BlockdevOnError on_target_error,
                             int creation_flags,
                             BlockCompletionFunc *cb, void *opaque,
                             JobTxn *txn, Error **errp);

 BdrvChild *bdrv_root_attach_child(BlockDriverState *child_bs,
                                   const char *child_name,
                                   const BdrvChildClass *child_class,
                                   BdrvChildRole child_role,
                                   uint64_t perm, uint64_t shared_perm,
                                   void *opaque, Error **errp);
 void bdrv_root_unref_child(BdrvChild *child);

 void bdrv_get_cumulative_perm(BlockDriverState *bs, uint64_t *perm,
                               uint64_t *shared_perm);

 /**
  * Sets a BdrvChild's permissions.  Avoid if the parent is a BDS; use
  * bdrv_child_refresh_perms() instead and make the parent's
  * .bdrv_child_perm() implementation return the correct values.
  */
 int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared,
                             Error **errp);

 /**
  * Calls bs->drv->bdrv_child_perm() and updates the child's permission
  * masks with the result.
  * Drivers should invoke this function whenever an event occurs that
  * makes their .bdrv_child_perm() implementation return different
  * values than before, but which will not result in the block layer
  * automatically refreshing the permissions.
  */
 int bdrv_child_refresh_perms(BlockDriverState *bs, BdrvChild *c, Error **errp);

 bool bdrv_recurse_can_replace(BlockDriverState *bs,
                               BlockDriverState *to_replace);

 /*
  * Default implementation for BlockDriver.bdrv_child_perm() that can
  * be used by block filters and image formats, as long as they use the
  * child_of_bds child class and set an appropriate BdrvChildRole.
  */
 void bdrv_default_perms(BlockDriverState *bs, BdrvChild *c,
                         BdrvChildRole role, BlockReopenQueue *reopen_queue,
                         uint64_t perm, uint64_t shared,
                         uint64_t *nperm, uint64_t *nshared);

 void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp);
 bool blk_dev_has_removable_media(BlockBackend *blk);
 void blk_dev_eject_request(BlockBackend *blk, bool force);
 bool blk_dev_is_medium_locked(BlockBackend *blk);

 void bdrv_restore_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap *backup);

 void bdrv_set_monitor_owned(BlockDriverState *bs);

 void blockdev_close_all_bdrv_states(void);

 BlockDriverState *bds_tree_init(QDict *bs_opts, Error **errp);

 /**
  * Simple implementation of bdrv_co_create_opts for protocol drivers
  * which only support creation via opening a file
  * (usually existing raw storage device)
  */
 int coroutine_fn bdrv_co_create_opts_simple(BlockDriver *drv,
                                             const char *filename,
                                             QemuOpts *opts,
                                             Error **errp);

 BdrvDirtyBitmap *block_dirty_bitmap_lookup(const char *node,
                                            const char *name,
                                            BlockDriverState **pbs,
                                            Error **errp);
 BdrvDirtyBitmap *block_dirty_bitmap_merge(const char *node, const char *target,
                                           BlockDirtyBitmapOrStrList *bms,
                                           HBitmap **backup, Error **errp);
 BdrvDirtyBitmap *block_dirty_bitmap_remove(const char *node, const char *name,
                                            bool release,
                                            BlockDriverState **bitmap_bs,
                                            Error **errp);


 BlockDriverState *bdrv_skip_implicit_filters(BlockDriverState *bs);

 /**
  * bdrv_add_aio_context_notifier:
  *
  * If a long-running job intends to be always run in the same AioContext as a
  * certain BDS, it may use this function to be notified of changes regarding the
  * association of the BDS to an AioContext.
  *
  * attached_aio_context() is called after the target BDS has been attached to a
  * new AioContext; detach_aio_context() is called before the target BDS is being
  * detached from its old AioContext.
  */
 void bdrv_add_aio_context_notifier(BlockDriverState *bs,
         void (*attached_aio_context)(AioContext *new_context, void *opaque),
         void (*detach_aio_context)(void *opaque), void *opaque);

 /**
  * bdrv_remove_aio_context_notifier:
  *
  * Unsubscribe of change notifications regarding the BDS's AioContext. The
  * parameters given here have to be the same as those given to
  * bdrv_add_aio_context_notifier().
  */
 void bdrv_remove_aio_context_notifier(BlockDriverState *bs,
                                       void (*aio_context_attached)(AioContext *,
                                                                    void *),
                                       void (*aio_context_detached)(void *),
                                       void *opaque);

 /**
  * End all quiescent sections started by bdrv_drain_all_begin(). This is
  * needed when deleting a BDS before bdrv_drain_all_end() is called.
  *
  * NOTE: this is an internal helper for bdrv_close() *only*. No one else
  * should call it.
  */
 void bdrv_drain_all_end_quiesce(BlockDriverState *bs);

 /**
  * Make sure that the function is running under both drain and BQL.
  * The latter protects from concurrent writings
  * from the GS API, while the former prevents concurrent reads
  * from I/O.
  */
 static inline void assert_bdrv_graph_writable(BlockDriverState *bs)
 {
     /*
      * TODO: this function is incomplete. Because the users of this
      * assert lack the necessary drains, check only for BQL.
      * Once the necessary drains are added,
      * assert also for qatomic_read(&bs->quiesce_counter) > 0
      */
     assert(qemu_in_main_thread());
 }

 #endif /* BLOCK_INT_GLOBAL_STATE_H */
	/*
	* QEMU System Emulator block driver
	*
	* Copyright (c) 2003 Fabrice Bellard
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*/

	#ifndef BLOCK_INT_GLOBAL_STATE_H
	#define BLOCK_INT_GLOBAL_STATE_H

	#include "block_int-common.h"

	/*
	* Global state (GS) API. These functions run under the BQL.
	*
	* See include/block/block-global-state.h for more information about
	* the GS API.
	*/

	/**
	* stream_start:
	* @job_id: The id of the newly-created job, or %NULL to use the
	* device name of @bs.
	* @bs: Block device to operate on.
	* @base: Block device that will become the new base, or %NULL to
	* flatten the whole backing file chain onto @bs.
	* @backing_file_str: The file name that will be written to @bs as the
	* the new backing file if the job completes. Ignored if @base is %NULL.
	* @creation_flags: Flags that control the behavior of the Job lifetime.
	* See @BlockJobCreateFlags
	* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
	* @on_error: The action to take upon error.
	* @filter_node_name: The node name that should be assigned to the filter
	* driver that the stream job inserts into the graph above
	* @bs. NULL means that a node name should be autogenerated.
	* @errp: Error object.
	*
	* Start a streaming operation on @bs. Clusters that are unallocated
	* in @bs, but allocated in any image between @base and @bs (both
	* exclusive) will be written to @bs. At the end of a successful
	* streaming job, the backing file of @bs will be changed to
	* @backing_file_str in the written image and to @base in the live
	* BlockDriverState.
	*/
	void stream_start(const char job_id, BlockDriverState bs,
	BlockDriverState base, const char backing_file_str,
	BlockDriverState *bottom,
	int creation_flags, int64_t speed,
	BlockdevOnError on_error,
	const char *filter_node_name,
	Error **errp);

	/**
	* commit_start:
	* @job_id: The id of the newly-created job, or %NULL to use the
	* device name of @bs.
	* @bs: Active block device.
	* @top: Top block device to be committed.
	* @base: Block device that will be written into, and become the new top.
	* @creation_flags: Flags that control the behavior of the Job lifetime.
	* See @BlockJobCreateFlags
	* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
	* @on_error: The action to take upon error.
	* @backing_file_str: String to use as the backing file in @top's overlay
	* @filter_node_name: The node name that should be assigned to the filter
	* driver that the commit job inserts into the graph above @top. NULL means
	* that a node name should be autogenerated.
	* @errp: Error object.
	*
	*/
	void commit_start(const char job_id, BlockDriverState bs,
	BlockDriverState base, BlockDriverState top,
	int creation_flags, int64_t speed,
	BlockdevOnError on_error, const char *backing_file_str,
	const char filter_node_name, Error *errp);
	/**
	* commit_active_start:
	* @job_id: The id of the newly-created job, or %NULL to use the
	* device name of @bs.
	* @bs: Active block device to be committed.
	* @base: Block device that will be written into, and become the new top.
	* @creation_flags: Flags that control the behavior of the Job lifetime.
	* See @BlockJobCreateFlags
	* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
	* @on_error: The action to take upon error.
	* @filter_node_name: The node name that should be assigned to the filter
	* driver that the commit job inserts into the graph above @bs. NULL means that
	* a node name should be autogenerated.
	* @cb: Completion function for the job.
	* @opaque: Opaque pointer value passed to @cb.
	* @auto_complete: Auto complete the job.
	* @errp: Error object.
	*
	*/
	BlockJob commit_active_start(const char job_id, BlockDriverState *bs,
	BlockDriverState *base, int creation_flags,
	int64_t speed, BlockdevOnError on_error,
	const char *filter_node_name,
	BlockCompletionFunc cb, void opaque,
	bool auto_complete, Error **errp);
	/*
	* mirror_start:
	* @job_id: The id of the newly-created job, or %NULL to use the
	* device name of @bs.
	* @bs: Block device to operate on.
	* @target: Block device to write to.
	* @replaces: Block graph node name to replace once the mirror is done. Can
	* only be used when full mirroring is selected.
	* @creation_flags: Flags that control the behavior of the Job lifetime.
	* See @BlockJobCreateFlags
	* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
	* @granularity: The chosen granularity for the dirty bitmap.
	* @buf_size: The amount of data that can be in flight at one time.
	* @mode: Whether to collapse all images in the chain to the target.
	* @backing_mode: How to establish the target's backing chain after completion.
	* @zero_target: Whether the target should be explicitly zero-initialized
	* @on_source_error: The action to take upon error reading from the source.
	* @on_target_error: The action to take upon error writing to the target.
	* @unmap: Whether to unmap target where source sectors only contain zeroes.
	* @filter_node_name: The node name that should be assigned to the filter
	* driver that the mirror job inserts into the graph above @bs. NULL means that
	* a node name should be autogenerated.
	* @copy_mode: When to trigger writes to the target.
	* @errp: Error object.
	*
	* Start a mirroring operation on @bs. Clusters that are allocated
	* in @bs will be written to @target until the job is cancelled or
	* manually completed. At the end of a successful mirroring job,
	* @bs will be switched to read from @target.
	*/
	void mirror_start(const char job_id, BlockDriverState bs,
	BlockDriverState target, const char replaces,
	int creation_flags, int64_t speed,
	uint32_t granularity, int64_t buf_size,
	MirrorSyncMode mode, BlockMirrorBackingMode backing_mode,
	bool zero_target,
	BlockdevOnError on_source_error,
	BlockdevOnError on_target_error,
	bool unmap, const char *filter_node_name,
	MirrorCopyMode copy_mode, Error **errp);

	/*
	* backup_job_create:
	* @job_id: The id of the newly-created job, or %NULL to use the
	* device name of @bs.
	* @bs: Block device to operate on.
	* @target: Block device to write to.
	* @speed: The maximum speed, in bytes per second, or 0 for unlimited.
	* @sync_mode: What parts of the disk image should be copied to the destination.
	* @sync_bitmap: The dirty bitmap if sync_mode is 'bitmap' or 'incremental'
	* @bitmap_mode: The bitmap synchronization policy to use.
	* @perf: Performance options. All actual fields assumed to be present,
	* all ".has_*" fields are ignored.
	* @on_source_error: The action to take upon error reading from the source.
	* @on_target_error: The action to take upon error writing to the target.
	* @creation_flags: Flags that control the behavior of the Job lifetime.
	* See @BlockJobCreateFlags
	* @cb: Completion function for the job.
	* @opaque: Opaque pointer value passed to @cb.
	* @txn: Transaction that this job is part of (may be NULL).
	*
	* Create a backup operation on @bs. Clusters in @bs are written to @target
	* until the job is cancelled or manually completed.
	*/
	BlockJob backup_job_create(const char job_id, BlockDriverState *bs,
	BlockDriverState *target, int64_t speed,
	MirrorSyncMode sync_mode,
	BdrvDirtyBitmap *sync_bitmap,
	BitmapSyncMode bitmap_mode,
	bool compress,
	const char *filter_node_name,
	BackupPerf *perf,
	BlockdevOnError on_source_error,
	BlockdevOnError on_target_error,
	int creation_flags,
	BlockCompletionFunc cb, void opaque,
	JobTxn txn, Error *errp);

	BdrvChild bdrv_root_attach_child(BlockDriverState child_bs,
	const char *child_name,
	const BdrvChildClass *child_class,
	BdrvChildRole child_role,
	uint64_t perm, uint64_t shared_perm,
	void opaque, Error *errp);
	void bdrv_root_unref_child(BdrvChild *child);

	void bdrv_get_cumulative_perm(BlockDriverState bs, uint64_t perm,
	uint64_t *shared_perm);

	/**
	* Sets a BdrvChild's permissions. Avoid if the parent is a BDS; use
	* bdrv_child_refresh_perms() instead and make the parent's
	* .bdrv_child_perm() implementation return the correct values.
	*/
	int bdrv_child_try_set_perm(BdrvChild *c, uint64_t perm, uint64_t shared,
	Error **errp);

	/**
	* Calls bs->drv->bdrv_child_perm() and updates the child's permission
	* masks with the result.
	* Drivers should invoke this function whenever an event occurs that
	* makes their .bdrv_child_perm() implementation return different
	* values than before, but which will not result in the block layer
	* automatically refreshing the permissions.
	*/
	int bdrv_child_refresh_perms(BlockDriverState bs, BdrvChild c, Error **errp);

	bool bdrv_recurse_can_replace(BlockDriverState *bs,
	BlockDriverState *to_replace);

	/*
	* Default implementation for BlockDriver.bdrv_child_perm() that can
	* be used by block filters and image formats, as long as they use the
	* child_of_bds child class and set an appropriate BdrvChildRole.
	*/
	void bdrv_default_perms(BlockDriverState bs, BdrvChild c,
	BdrvChildRole role, BlockReopenQueue *reopen_queue,
	uint64_t perm, uint64_t shared,
	uint64_t nperm, uint64_t nshared);

	void blk_dev_change_media_cb(BlockBackend blk, bool load, Error *errp);
	bool blk_dev_has_removable_media(BlockBackend *blk);
	void blk_dev_eject_request(BlockBackend *blk, bool force);
	bool blk_dev_is_medium_locked(BlockBackend *blk);

	void bdrv_restore_dirty_bitmap(BdrvDirtyBitmap bitmap, HBitmap backup);

	void bdrv_set_monitor_owned(BlockDriverState *bs);

	void blockdev_close_all_bdrv_states(void);

	BlockDriverState bds_tree_init(QDict bs_opts, Error **errp);

	/**
	* Simple implementation of bdrv_co_create_opts for protocol drivers
	* which only support creation via opening a file
	* (usually existing raw storage device)
	*/
	int coroutine_fn bdrv_co_create_opts_simple(BlockDriver *drv,
	const char *filename,
	QemuOpts *opts,
	Error **errp);

	BdrvDirtyBitmap block_dirty_bitmap_lookup(const char node,
	const char *name,
	BlockDriverState **pbs,
	Error **errp);
	BdrvDirtyBitmap block_dirty_bitmap_merge(const char node, const char *target,
	BlockDirtyBitmapOrStrList *bms,
	HBitmap backup, Error errp);
	BdrvDirtyBitmap block_dirty_bitmap_remove(const char node, const char *name,
	bool release,
	BlockDriverState **bitmap_bs,
	Error **errp);


	BlockDriverState bdrv_skip_implicit_filters(BlockDriverState bs);

	/**
	* bdrv_add_aio_context_notifier:
	*
	* If a long-running job intends to be always run in the same AioContext as a
	* certain BDS, it may use this function to be notified of changes regarding the
	* association of the BDS to an AioContext.
	*
	* attached_aio_context() is called after the target BDS has been attached to a
	* new AioContext; detach_aio_context() is called before the target BDS is being
	* detached from its old AioContext.
	*/
	void bdrv_add_aio_context_notifier(BlockDriverState *bs,
	void (attached_aio_context)(AioContext new_context, void *opaque),
	void (detach_aio_context)(void opaque), void *opaque);

	/**
	* bdrv_remove_aio_context_notifier:
	*
	* Unsubscribe of change notifications regarding the BDS's AioContext. The
	* parameters given here have to be the same as those given to
	* bdrv_add_aio_context_notifier().
	*/
	void bdrv_remove_aio_context_notifier(BlockDriverState *bs,
	void (aio_context_attached)(AioContext ,
	void *),
	void (aio_context_detached)(void ),
	void *opaque);

	/**
	* End all quiescent sections started by bdrv_drain_all_begin(). This is
	* needed when deleting a BDS before bdrv_drain_all_end() is called.
	*
	* NOTE: this is an internal helper for bdrv_close() only. No one else
	* should call it.
	*/
	void bdrv_drain_all_end_quiesce(BlockDriverState *bs);

	/**
	* Make sure that the function is running under both drain and BQL.
	* The latter protects from concurrent writings
	* from the GS API, while the former prevents concurrent reads
	* from I/O.
	*/
	static inline void assert_bdrv_graph_writable(BlockDriverState *bs)
	{
	/*
	* TODO: this function is incomplete. Because the users of this
	* assert lack the necessary drains, check only for BQL.
	* Once the necessary drains are added,
	* assert also for qatomic_read(&bs->quiesce_counter) > 0
	*/
	assert(qemu_in_main_thread());
	}

	#endif /* BLOCK_INT_GLOBAL_STATE_H */