diff options
Diffstat (limited to 'include')
| -rw-r--r-- | include/block/block.h | 2 | ||||
| -rw-r--r-- | include/block/block_int.h | 95 |
2 files changed, 61 insertions, 36 deletions
diff --git a/include/block/block.h b/include/block/block.h index 6e36154061..981ab5b314 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -532,7 +532,7 @@ BlockDriverState *bdrv_next(BdrvNextIterator *it); void bdrv_next_cleanup(BdrvNextIterator *it); BlockDriverState *bdrv_next_monitor_owned(BlockDriverState *bs); -bool bdrv_is_encrypted(BlockDriverState *bs); +bool bdrv_supports_compressed_writes(BlockDriverState *bs); void bdrv_iterate_format(void (*it)(void *opaque, const char *name), void *opaque, bool read_only); const char *bdrv_get_node_name(const BlockDriverState *bs); diff --git a/include/block/block_int.h b/include/block/block_int.h index 9da7a42927..38cad9d15c 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -92,9 +92,17 @@ struct BlockDriver { int instance_size; /* set to true if the BlockDriver is a block filter. Block filters pass - * certain callbacks that refer to data (see block.c) to their bs->file if - * the driver doesn't implement them. Drivers that do not wish to forward - * must implement them and return -ENOTSUP. + * certain callbacks that refer to data (see block.c) to their bs->file + * or bs->backing (whichever one exists) if the driver doesn't implement + * them. Drivers that do not wish to forward must implement them and return + * -ENOTSUP. + * Note that filters are not allowed to modify data. + * + * Filters generally cannot have more than a single filtered child, + * because the data they present must at all times be the same as + * that on their filtered child. That would be impossible to + * achieve for multiple filtered children. + * (And this filtered child must then be bs->file or bs->backing.) */ bool is_filter; /* @@ -839,11 +847,20 @@ struct BlockDriverState { bool walking_aio_notifiers; /* to make removal during iteration safe */ char filename[PATH_MAX]; - char backing_file[PATH_MAX]; /* if non zero, the image is a diff of - this file image */ - /* The backing filename indicated by the image header; if we ever - * open this file, then this is replaced by the resulting BDS's - * filename (i.e. after a bdrv_refresh_filename() run). */ + /* + * If not empty, this image is a diff in relation to backing_file. + * Note that this is the name given in the image header and + * therefore may or may not be equal to .backing->bs->filename. + * If this field contains a relative path, it is to be resolved + * relatively to the overlay's location. + */ + char backing_file[PATH_MAX]; + /* + * The backing filename indicated by the image header. Contrary + * to backing_file, if we ever open this file, auto_backing_file + * is replaced by the resulting BDS's filename (i.e. after a + * bdrv_refresh_filename() run). + */ char auto_backing_file[PATH_MAX]; char backing_format[16]; /* if non-zero and backing_file exists */ @@ -995,11 +1012,6 @@ typedef enum BlockMirrorBackingMode { MIRROR_LEAVE_BACKING_CHAIN, } BlockMirrorBackingMode; -static inline BlockDriverState *backing_bs(BlockDriverState *bs) -{ - return bs->backing ? bs->backing->bs : NULL; -} - /* Essential block drivers which must always be statically linked into qemu, and * which therefore can be accessed without using bdrv_find_format() */ @@ -1050,6 +1062,8 @@ BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, void bdrv_parse_filename_strip_prefix(const char *filename, const char *prefix, QDict *options); +bool bdrv_backing_overridden(BlockDriverState *bs); + /** * bdrv_add_before_write_notifier: @@ -1300,28 +1314,6 @@ void bdrv_default_perms(BlockDriverState *bs, BdrvChild *c, uint64_t perm, uint64_t shared, uint64_t *nperm, uint64_t *nshared); -/* - * Default implementation for drivers to pass bdrv_co_block_status() to - * their file. - */ -int coroutine_fn bdrv_co_block_status_from_file(BlockDriverState *bs, - bool want_zero, - int64_t offset, - int64_t bytes, - int64_t *pnum, - int64_t *map, - BlockDriverState **file); -/* - * Default implementation for drivers to pass bdrv_co_block_status() to - * their backing file. - */ -int coroutine_fn bdrv_co_block_status_from_backing(BlockDriverState *bs, - bool want_zero, - int64_t offset, - int64_t bytes, - int64_t *pnum, - int64_t *map, - BlockDriverState **file); const char *bdrv_get_parent_name(const BlockDriverState *bs); void blk_dev_change_media_cb(BlockBackend *blk, bool load, Error **errp); bool blk_dev_has_removable_media(BlockBackend *blk); @@ -1382,4 +1374,37 @@ BdrvDirtyBitmap *block_dirty_bitmap_remove(const char *node, const char *name, BlockDriverState **bitmap_bs, Error **errp); +BdrvChild *bdrv_cow_child(BlockDriverState *bs); +BdrvChild *bdrv_filter_child(BlockDriverState *bs); +BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs); +BdrvChild *bdrv_primary_child(BlockDriverState *bs); +BlockDriverState *bdrv_skip_implicit_filters(BlockDriverState *bs); +BlockDriverState *bdrv_skip_filters(BlockDriverState *bs); +BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs); + +static inline BlockDriverState *child_bs(BdrvChild *child) +{ + return child ? child->bs : NULL; +} + +static inline BlockDriverState *bdrv_cow_bs(BlockDriverState *bs) +{ + return child_bs(bdrv_cow_child(bs)); +} + +static inline BlockDriverState *bdrv_filter_bs(BlockDriverState *bs) +{ + return child_bs(bdrv_filter_child(bs)); +} + +static inline BlockDriverState *bdrv_filter_or_cow_bs(BlockDriverState *bs) +{ + return child_bs(bdrv_filter_or_cow_child(bs)); +} + +static inline BlockDriverState *bdrv_primary_bs(BlockDriverState *bs) +{ + return child_bs(bdrv_primary_child(bs)); +} + #endif /* BLOCK_INT_H */ |