diff options
Diffstat (limited to 'include/block')
| -rw-r--r-- | include/block/block_int-common.h | 445 |
1 files changed, 237 insertions, 208 deletions
diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h index b92e3630fd..f05ebb0da3 100644 --- a/include/block/block_int-common.h +++ b/include/block/block_int-common.h @@ -96,6 +96,11 @@ typedef struct BdrvTrackedRequest { struct BlockDriver { + /* + * These fields are initialized when this object is created, + * and are never changed afterwards. + */ + const char *format_name; int instance_size; @@ -123,6 +128,69 @@ struct BlockDriver { bool is_format; /* + * Drivers not implementing bdrv_parse_filename nor bdrv_open should have + * this field set to true, except ones that are defined only by their + * child's bs. + * An example of the last type will be the quorum block driver. + */ + bool bdrv_needs_filename; + + /* + * Set if a driver can support backing files. This also implies the + * following semantics: + * + * - Return status 0 of .bdrv_co_block_status means that corresponding + * blocks are not allocated in this layer of backing-chain + * - For such (unallocated) blocks, read will: + * - fill buffer with zeros if there is no backing file + * - read from the backing file otherwise, where the block layer + * takes care of reading zeros beyond EOF if backing file is short + */ + bool supports_backing; + + bool has_variable_length; + + /* + * Drivers setting this field must be able to work with just a plain + * filename with '<protocol_name>:' as a prefix, and no other options. + * Options may be extracted from the filename by implementing + * bdrv_parse_filename. + */ + const char *protocol_name; + + /* List of options for creating images, terminated by name == NULL */ + QemuOptsList *create_opts; + + /* List of options for image amend */ + QemuOptsList *amend_opts; + + /* + * If this driver supports reopening images this contains a + * NULL-terminated list of the runtime options that can be + * modified. If an option in this list is unspecified during + * reopen then it _must_ be reset to its default value or return + * an error. + */ + const char *const *mutable_opts; + + /* + * Pointer to a NULL-terminated array of names of strong options + * that can be specified for bdrv_open(). A strong option is one + * that changes the data of a BDS. + * If this pointer is NULL, the array is considered empty. + * "filename" and "driver" are always considered strong. + */ + const char *const *strong_runtime_opts; + + + /* + * Global state (GS) API. These functions run under the BQL. + * + * See include/block/block-global-state.h for more information about + * the GS API. + */ + + /* * This function is invoked under BQL before .bdrv_co_amend() * (which in contrast does not necessarily run under the BQL) * to allow driver-specific initialization code that requires @@ -143,7 +211,6 @@ struct BlockDriver { bool (*bdrv_recurse_can_replace)(BlockDriverState *bs, BlockDriverState *to_replace); - int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename); int (*bdrv_probe_device)(const char *filename); /* @@ -152,28 +219,8 @@ struct BlockDriver { */ void (*bdrv_parse_filename)(const char *filename, QDict *options, Error **errp); - /* - * Drivers not implementing bdrv_parse_filename nor bdrv_open should have - * this field set to true, except ones that are defined only by their - * child's bs. - * An example of the last type will be the quorum block driver. - */ - bool bdrv_needs_filename; - - /* - * Set if a driver can support backing files. This also implies the - * following semantics: - * - * - Return status 0 of .bdrv_co_block_status means that corresponding - * blocks are not allocated in this layer of backing-chain - * - For such (unallocated) blocks, read will: - * - fill buffer with zeros if there is no backing file - * - read from the backing file otherwise, where the block layer - * takes care of reading zeros beyond EOF if backing file is short - */ - bool supports_backing; - /* For handling image reopen for split or non-split files */ + /* For handling image reopen for split or non-split files. */ int (*bdrv_reopen_prepare)(BDRVReopenState *reopen_state, BlockReopenQueue *queue, Error **errp); void (*bdrv_reopen_commit)(BDRVReopenState *reopen_state); @@ -189,7 +236,6 @@ struct BlockDriver { Error **errp); void (*bdrv_close)(BlockDriverState *bs); - int coroutine_fn (*bdrv_co_create)(BlockdevCreateOptions *opts, Error **errp); int coroutine_fn (*bdrv_co_create_opts)(BlockDriver *drv, @@ -197,11 +243,6 @@ struct BlockDriver { QemuOpts *opts, Error **errp); - int coroutine_fn (*bdrv_co_amend)(BlockDriverState *bs, - BlockdevAmendOptions *opts, - bool force, - Error **errp); - int (*bdrv_amend_options)(BlockDriverState *bs, QemuOpts *opts, BlockDriverAmendStatusCB *status_cb, @@ -248,6 +289,174 @@ struct BlockDriver { */ char *(*bdrv_dirname)(BlockDriverState *bs, Error **errp); + /* + * This informs the driver that we are no longer interested in the result + * of in-flight requests, so don't waste the time if possible. + * + * One example usage is to avoid waiting for an nbd target node reconnect + * timeout during job-cancel with force=true. + */ + void (*bdrv_cancel_in_flight)(BlockDriverState *bs); + + int (*bdrv_inactivate)(BlockDriverState *bs); + + int (*bdrv_snapshot_create)(BlockDriverState *bs, + QEMUSnapshotInfo *sn_info); + int (*bdrv_snapshot_goto)(BlockDriverState *bs, + const char *snapshot_id); + int (*bdrv_snapshot_delete)(BlockDriverState *bs, + const char *snapshot_id, + const char *name, + Error **errp); + int (*bdrv_snapshot_list)(BlockDriverState *bs, + QEMUSnapshotInfo **psn_info); + int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, + const char *snapshot_id, + const char *name, + Error **errp); + + int (*bdrv_change_backing_file)(BlockDriverState *bs, + const char *backing_file, const char *backing_fmt); + + /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */ + int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event, + const char *tag); + int (*bdrv_debug_remove_breakpoint)(BlockDriverState *bs, + const char *tag); + int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag); + bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag); + + void (*bdrv_refresh_limits)(BlockDriverState *bs, Error **errp); + + /* + * Returns 1 if newly created images are guaranteed to contain only + * zeros, 0 otherwise. + */ + int (*bdrv_has_zero_init)(BlockDriverState *bs); + + /* + * Remove fd handlers, timers, and other event loop callbacks so the event + * loop is no longer in use. Called with no in-flight requests and in + * depth-first traversal order with parents before child nodes. + */ + void (*bdrv_detach_aio_context)(BlockDriverState *bs); + + /* + * Add fd handlers, timers, and other event loop callbacks so I/O requests + * can be processed again. Called with no in-flight requests and in + * depth-first traversal order with child nodes before parent nodes. + */ + void (*bdrv_attach_aio_context)(BlockDriverState *bs, + AioContext *new_context); + + /** + * Try to get @bs's logical and physical block size. + * On success, store them in @bsz and return zero. + * On failure, return negative errno. + */ + int (*bdrv_probe_blocksizes)(BlockDriverState *bs, BlockSizes *bsz); + /** + * Try to get @bs's geometry (cyls, heads, sectors) + * On success, store them in @geo and return 0. + * On failure return -errno. + * Only drivers that want to override guest geometry implement this + * callback; see hd_geometry_guess(). + */ + int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo); + + void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child, + Error **errp); + void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child, + Error **errp); + + /** + * Informs the block driver that a permission change is intended. The + * driver checks whether the change is permissible and may take other + * preparations for the change (e.g. get file system locks). This operation + * is always followed either by a call to either .bdrv_set_perm or + * .bdrv_abort_perm_update. + * + * Checks whether the requested set of cumulative permissions in @perm + * can be granted for accessing @bs and whether no other users are using + * permissions other than those given in @shared (both arguments take + * BLK_PERM_* bitmasks). + * + * If both conditions are met, 0 is returned. Otherwise, -errno is returned + * and errp is set to an error describing the conflict. + */ + int (*bdrv_check_perm)(BlockDriverState *bs, uint64_t perm, + uint64_t shared, Error **errp); + + /** + * Called to inform the driver that the set of cumulative set of used + * permissions for @bs has changed to @perm, and the set of sharable + * permission to @shared. The driver can use this to propagate changes to + * its children (i.e. request permissions only if a parent actually needs + * them). + * + * This function is only invoked after bdrv_check_perm(), so block drivers + * may rely on preparations made in their .bdrv_check_perm implementation. + */ + void (*bdrv_set_perm)(BlockDriverState *bs, uint64_t perm, uint64_t shared); + + /* + * Called to inform the driver that after a previous bdrv_check_perm() + * call, the permission update is not performed and any preparations made + * for it (e.g. taken file locks) need to be undone. + * + * This function can be called even for nodes that never saw a + * bdrv_check_perm() call. It is a no-op then. + */ + void (*bdrv_abort_perm_update)(BlockDriverState *bs); + + /** + * Returns in @nperm and @nshared the permissions that the driver for @bs + * needs on its child @c, based on the cumulative permissions requested by + * the parents in @parent_perm and @parent_shared. + * + * If @c is NULL, return the permissions for attaching a new child for the + * given @child_class and @role. + * + * If @reopen_queue is non-NULL, don't return the currently needed + * permissions, but those that will be needed after applying the + * @reopen_queue. + */ + void (*bdrv_child_perm)(BlockDriverState *bs, BdrvChild *c, + BdrvChildRole role, + BlockReopenQueue *reopen_queue, + uint64_t parent_perm, uint64_t parent_shared, + uint64_t *nperm, uint64_t *nshared); + + /** + * Register/unregister a buffer for I/O. For example, when the driver is + * interested to know the memory areas that will later be used in iovs, so + * that it can do IOMMU mapping with VFIO etc., in order to get better + * performance. In the case of VFIO drivers, this callback is used to do + * DMA mapping for hot buffers. + */ + void (*bdrv_register_buf)(BlockDriverState *bs, void *host, size_t size); + void (*bdrv_unregister_buf)(BlockDriverState *bs, void *host); + + /* + * This field is modified only under the BQL, and is part of + * the global state. + */ + QLIST_ENTRY(BlockDriver) list; + + /* + * I/O API functions. These functions are thread-safe. + * + * See include/block/block-io.h for more information about + * the I/O API. + */ + + int (*bdrv_probe)(const uint8_t *buf, int buf_size, const char *filename); + + int coroutine_fn (*bdrv_co_amend)(BlockDriverState *bs, + BlockdevAmendOptions *opts, + bool force, + Error **errp); + /* aio */ BlockAIOCB *(*bdrv_aio_preadv)(BlockDriverState *bs, int64_t offset, int64_t bytes, QEMUIOVector *qiov, @@ -389,20 +598,10 @@ struct BlockDriver { int64_t *map, BlockDriverState **file); /* - * This informs the driver that we are no longer interested in the result - * of in-flight requests, so don't waste the time if possible. - * - * One example usage is to avoid waiting for an nbd target node reconnect - * timeout during job-cancel with force=true. - */ - void (*bdrv_cancel_in_flight)(BlockDriverState *bs); - - /* * Invalidate any cached meta-data. */ void coroutine_fn (*bdrv_co_invalidate_cache)(BlockDriverState *bs, Error **errp); - int (*bdrv_inactivate)(BlockDriverState *bs); /* * Flushes all data for all layers by calling bdrv_co_flush for underlying @@ -429,14 +628,6 @@ struct BlockDriver { int coroutine_fn (*bdrv_co_flush_to_os)(BlockDriverState *bs); /* - * Drivers setting this field must be able to work with just a plain - * filename with '<protocol_name>:' as a prefix, and no other options. - * Options may be extracted from the filename by implementing - * bdrv_parse_filename. - */ - const char *protocol_name; - - /* * Truncate @bs to @offset bytes using the given @prealloc mode * when growing. Modes other than PREALLOC_MODE_OFF should be * rejected when shrinking @bs. @@ -453,7 +644,6 @@ struct BlockDriver { bool exact, PreallocMode prealloc, BdrvRequestFlags flags, Error **errp); int64_t (*bdrv_getlength)(BlockDriverState *bs); - bool has_variable_length; int64_t (*bdrv_get_allocated_file_size)(BlockDriverState *bs); BlockMeasureInfo *(*bdrv_measure)(QemuOpts *opts, BlockDriverState *in_bs, Error **errp); @@ -464,20 +654,6 @@ struct BlockDriver { int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset); - int (*bdrv_snapshot_create)(BlockDriverState *bs, - QEMUSnapshotInfo *sn_info); - int (*bdrv_snapshot_goto)(BlockDriverState *bs, - const char *snapshot_id); - int (*bdrv_snapshot_delete)(BlockDriverState *bs, - const char *snapshot_id, - const char *name, - Error **errp); - int (*bdrv_snapshot_list)(BlockDriverState *bs, - QEMUSnapshotInfo **psn_info); - int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, - const char *snapshot_id, - const char *name, - Error **errp); int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi); ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs, @@ -491,9 +667,6 @@ struct BlockDriver { QEMUIOVector *qiov, int64_t pos); - int (*bdrv_change_backing_file)(BlockDriverState *bs, - const char *backing_file, const char *backing_fmt); - /* removable device specific */ bool (*bdrv_is_inserted)(BlockDriverState *bs); void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag); @@ -506,21 +679,6 @@ struct BlockDriver { int coroutine_fn (*bdrv_co_ioctl)(BlockDriverState *bs, unsigned long int req, void *buf); - /* List of options for creating images, terminated by name == NULL */ - QemuOptsList *create_opts; - - /* List of options for image amend */ - QemuOptsList *amend_opts; - - /* - * If this driver supports reopening images this contains a - * NULL-terminated list of the runtime options that can be - * modified. If an option in this list is unspecified during - * reopen then it _must_ be reset to its default value or return - * an error. - */ - const char *const *mutable_opts; - /* * Returns 0 for completed check, -errno for internal errors. * The check results are stored in result. @@ -531,57 +689,11 @@ struct BlockDriver { void (*bdrv_debug_event)(BlockDriverState *bs, BlkdebugEvent event); - /* TODO Better pass a option string/QDict/QemuOpts to add any rule? */ - int (*bdrv_debug_breakpoint)(BlockDriverState *bs, const char *event, - const char *tag); - int (*bdrv_debug_remove_breakpoint)(BlockDriverState *bs, - const char *tag); - int (*bdrv_debug_resume)(BlockDriverState *bs, const char *tag); - bool (*bdrv_debug_is_suspended)(BlockDriverState *bs, const char *tag); - - void (*bdrv_refresh_limits)(BlockDriverState *bs, Error **errp); - - /* - * Returns 1 if newly created images are guaranteed to contain only - * zeros, 0 otherwise. - */ - int (*bdrv_has_zero_init)(BlockDriverState *bs); - - /* - * Remove fd handlers, timers, and other event loop callbacks so the event - * loop is no longer in use. Called with no in-flight requests and in - * depth-first traversal order with parents before child nodes. - */ - void (*bdrv_detach_aio_context)(BlockDriverState *bs); - - /* - * Add fd handlers, timers, and other event loop callbacks so I/O requests - * can be processed again. Called with no in-flight requests and in - * depth-first traversal order with child nodes before parent nodes. - */ - void (*bdrv_attach_aio_context)(BlockDriverState *bs, - AioContext *new_context); - /* io queue for linux-aio */ void (*bdrv_io_plug)(BlockDriverState *bs); void (*bdrv_io_unplug)(BlockDriverState *bs); /** - * Try to get @bs's logical and physical block size. - * On success, store them in @bsz and return zero. - * On failure, return negative errno. - */ - int (*bdrv_probe_blocksizes)(BlockDriverState *bs, BlockSizes *bsz); - /** - * Try to get @bs's geometry (cyls, heads, sectors) - * On success, store them in @geo and return 0. - * On failure return -errno. - * Only drivers that want to override guest geometry implement this - * callback; see hd_geometry_guess(). - */ - int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo); - - /** * bdrv_co_drain_begin is called if implemented in the beginning of a * drain operation to drain and stop any internal sources of requests in * the driver. @@ -594,69 +706,6 @@ struct BlockDriver { void coroutine_fn (*bdrv_co_drain_begin)(BlockDriverState *bs); void coroutine_fn (*bdrv_co_drain_end)(BlockDriverState *bs); - void (*bdrv_add_child)(BlockDriverState *parent, BlockDriverState *child, - Error **errp); - void (*bdrv_del_child)(BlockDriverState *parent, BdrvChild *child, - Error **errp); - - /** - * Informs the block driver that a permission change is intended. The - * driver checks whether the change is permissible and may take other - * preparations for the change (e.g. get file system locks). This operation - * is always followed either by a call to either .bdrv_set_perm or - * .bdrv_abort_perm_update. - * - * Checks whether the requested set of cumulative permissions in @perm - * can be granted for accessing @bs and whether no other users are using - * permissions other than those given in @shared (both arguments take - * BLK_PERM_* bitmasks). - * - * If both conditions are met, 0 is returned. Otherwise, -errno is returned - * and errp is set to an error describing the conflict. - */ - int (*bdrv_check_perm)(BlockDriverState *bs, uint64_t perm, - uint64_t shared, Error **errp); - - /** - * Called to inform the driver that the set of cumulative set of used - * permissions for @bs has changed to @perm, and the set of sharable - * permission to @shared. The driver can use this to propagate changes to - * its children (i.e. request permissions only if a parent actually needs - * them). - * - * This function is only invoked after bdrv_check_perm(), so block drivers - * may rely on preparations made in their .bdrv_check_perm implementation. - */ - void (*bdrv_set_perm)(BlockDriverState *bs, uint64_t perm, uint64_t shared); - - /* - * Called to inform the driver that after a previous bdrv_check_perm() - * call, the permission update is not performed and any preparations made - * for it (e.g. taken file locks) need to be undone. - * - * This function can be called even for nodes that never saw a - * bdrv_check_perm() call. It is a no-op then. - */ - void (*bdrv_abort_perm_update)(BlockDriverState *bs); - - /** - * Returns in @nperm and @nshared the permissions that the driver for @bs - * needs on its child @c, based on the cumulative permissions requested by - * the parents in @parent_perm and @parent_shared. - * - * If @c is NULL, return the permissions for attaching a new child for the - * given @child_class and @role. - * - * If @reopen_queue is non-NULL, don't return the currently needed - * permissions, but those that will be needed after applying the - * @reopen_queue. - */ - void (*bdrv_child_perm)(BlockDriverState *bs, BdrvChild *c, - BdrvChildRole role, - BlockReopenQueue *reopen_queue, - uint64_t parent_perm, uint64_t parent_shared, - uint64_t *nperm, uint64_t *nshared); - bool (*bdrv_supports_persistent_dirty_bitmap)(BlockDriverState *bs); bool (*bdrv_co_can_store_new_dirty_bitmap)(BlockDriverState *bs, const char *name, @@ -665,26 +714,6 @@ struct BlockDriver { int (*bdrv_co_remove_persistent_dirty_bitmap)(BlockDriverState *bs, const char *name, Error **errp); - - /** - * Register/unregister a buffer for I/O. For example, when the driver is - * interested to know the memory areas that will later be used in iovs, so - * that it can do IOMMU mapping with VFIO etc., in order to get better - * performance. In the case of VFIO drivers, this callback is used to do - * DMA mapping for hot buffers. - */ - void (*bdrv_register_buf)(BlockDriverState *bs, void *host, size_t size); - void (*bdrv_unregister_buf)(BlockDriverState *bs, void *host); - QLIST_ENTRY(BlockDriver) list; - - /* - * Pointer to a NULL-terminated array of names of strong options - * that can be specified for bdrv_open(). A strong option is one - * that changes the data of a BDS. - * If this pointer is NULL, the array is considered empty. - * "filename" and "driver" are always considered strong. - */ - const char *const *strong_runtime_opts; }; static inline bool block_driver_can_compress(BlockDriver *drv) |