Similar to the header split, also the function pointers in BlockDriver
can be split in I/O and global state.
Signed-off-by: Emanuele Giuseppe Esposito <eespo...@redhat.com>
---
include/block/block_int-common.h | 440 +++++++++++++++++--------------
1 file changed, 235 insertions(+), 205 deletions(-)
diff --git a/include/block/block_int-common.h b/include/block/block_int-common.h
index 70534f94ae..0e63dc694f 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;
@@ -121,23 +126,7 @@ struct BlockDriver {
* on those children.
*/
bool is_format;
- /*
- * Return true if @to_replace can be replaced by a BDS with the
- * same data as @bs without it affecting @bs's behavior (that is,
- * without it being visible to @bs's parents).
- */
- 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);
- /*
- * Any driver implementing this callback is expected to be able to handle
- * NULL file names in its .bdrv_open() implementation.
- */
- 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
@@ -159,7 +148,66 @@ struct BlockDriver {
*/
bool supports_backing;
- /* For handling image reopen for split or non-split files */
+ 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 lock.
+ *
+ * See include/block/block-global-state.h for more information about
+ * the GS API.
+ */
+
+ /*
+ * Return true if @to_replace can be replaced by a BDS with the
+ * same data as @bs without it affecting @bs's behavior (that is,
+ * without it being visible to @bs's parents).
+ */
+ 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);
+
+ /*
+ * Any driver implementing this callback is expected to be able to handle
+ * NULL file names in its .bdrv_open() implementation.
+ */
+ void (*bdrv_parse_filename)(const char *filename, QDict *options,
+ Error **errp);
+
+ /* 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);
@@ -175,7 +223,6 @@ 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,
@@ -183,11 +230,6 @@ 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,
@@ -234,6 +276,176 @@ 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);
+
+ /* removable device specific */
+ void (*bdrv_eject)(BlockDriverState *bs, bool eject_flag);
+ void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked);
+
+ /* 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 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,
@@ -374,21 +586,11 @@ struct BlockDriver {
bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum,
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
@@ -414,14 +616,6 @@ 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
@@ -439,7 +633,6 @@ 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);
@@ -450,20 +643,6 @@ 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,
@@ -477,13 +656,8 @@ 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);
- void (*bdrv_lock_medium)(BlockDriverState *bs, bool locked);
/* to control generic scsi devices */
BlockAIOCB *(*bdrv_aio_ioctl)(BlockDriverState *bs,
@@ -492,21 +666,6 @@ 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.
@@ -517,56 +676,10 @@ 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
@@ -580,69 +693,6 @@ 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,
@@ -651,26 +701,6 @@ 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)
--
2.27.0
