xfs: don't bother looking at the refcount tree for reads
There is no need to trim an extent into a shared or non-shared one, or
report any flags for plain old reads.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index d907eb9..1dabf2e 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -996,11 +996,14 @@
return error;
}
- /* Trim the mapping to the nearest shared extent boundary. */
- error = xfs_reflink_trim_around_shared(ip, &imap, &shared, &trimmed);
- if (error) {
- xfs_iunlock(ip, lockmode);
- return error;
+ if (flags & (IOMAP_WRITE | IOMAP_ZERO | IOMAP_REPORT)) {
+ /* Trim the mapping to the nearest shared extent boundary. */
+ error = xfs_reflink_trim_around_shared(ip, &imap, &shared,
+ &trimmed);
+ if (error) {
+ xfs_iunlock(ip, lockmode);
+ return error;
+ }
}
if ((flags & IOMAP_WRITE) && imap_needs_alloc(inode, &imap, nimaps)) {