xfs: unshare a range of blocks via fallocate
Unshare all shared extents if the user calls fallocate with the new
unshare mode flag set, so that we can guarantee that a subsequent
write will not ENOSPC.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[hch: pass inode instead of file to xfs_reflink_dirty_range,
use iomap infrastructure for copy up]
Signed-off-by: Christoph Hellwig <hch@lst.de>
diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c
index 39fde9f..07f951d 100644
--- a/fs/xfs/xfs_file.c
+++ b/fs/xfs/xfs_file.c
@@ -848,7 +848,7 @@
#define XFS_FALLOC_FL_SUPPORTED \
(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE | \
FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE | \
- FALLOC_FL_INSERT_RANGE)
+ FALLOC_FL_INSERT_RANGE | FALLOC_FL_UNSHARE_RANGE)
STATIC long
xfs_file_fallocate(
@@ -938,9 +938,15 @@
if (mode & FALLOC_FL_ZERO_RANGE)
error = xfs_zero_file_space(ip, offset, len);
- else
+ else {
+ if (mode & FALLOC_FL_UNSHARE_RANGE) {
+ error = xfs_reflink_unshare(ip, offset, len);
+ if (error)
+ goto out_unlock;
+ }
error = xfs_alloc_file_space(ip, offset, len,
XFS_BMAPI_PREALLOC);
+ }
if (error)
goto out_unlock;
}