diff options
| author | Goldwyn Rodrigues | 2019-10-18 16:44:10 -0700 |
|---|---|---|
| committer | Darrick J. Wong | 2019-10-21 08:51:59 -0700 |
| commit | c039b99792726346ad46ff17c5a5bcb77a5edac4 (patch) | |
| tree | e9034adc21c6fc3ad6fc775e8f3225e35b015d50 /include | |
| parent | eb81cf9d0e18d438e27339e0d1a49d3ac8644674 (diff) | |
iomap: use a srcmap for a read-modify-write I/O
The srcmap is used to identify where the read is to be performed from.
It is passed to ->iomap_begin, which can fill it in if we need to read
data for partially written blocks from a different location than the
write target. The srcmap is only supported for buffered writes so far.
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
[hch: merged two patches, removed the IOMAP_F_COW flag, use iomap as
srcmap if not set, adjust length down to srcmap end as well]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/iomap.h | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/include/linux/iomap.h b/include/linux/iomap.h index 53e6e2275d3d..8b09463dae0d 100644 --- a/include/linux/iomap.h +++ b/include/linux/iomap.h @@ -129,7 +129,8 @@ struct iomap_ops { * The actual length is returned in iomap->length. */ int (*iomap_begin)(struct inode *inode, loff_t pos, loff_t length, - unsigned flags, struct iomap *iomap); + unsigned flags, struct iomap *iomap, + struct iomap *srcmap); /* * Commit and/or unreserve space previous allocated using iomap_begin. @@ -145,7 +146,7 @@ struct iomap_ops { * Main iomap iterator function. */ typedef loff_t (*iomap_actor_t)(struct inode *inode, loff_t pos, loff_t len, - void *data, struct iomap *iomap); + void *data, struct iomap *iomap, struct iomap *srcmap); loff_t iomap_apply(struct inode *inode, loff_t pos, loff_t length, unsigned flags, const struct iomap_ops *ops, void *data, |