xfs: don't pass iomap flags to xfs_reflink_allocate_cow

Don't pass raw iomap flags to xfs_reflink_allocate_cow; signal our
intention with a boolean argument.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>

1 files changed, 7 insertions, 6 deletions

diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index 01210eae8bf3..fa6621448d5e 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -983,6 +983,7 @@ xfs_file_iomap_begin(
 	 */
 	if (xfs_is_cow_inode(ip)) {
 		struct xfs_bmbt_irec	orig = imap;
+		bool			directio = (flags & IOMAP_DIRECT);
 
 		/* if zeroing doesn't need COW allocation, then we are done. */
 		if ((flags & IOMAP_ZERO) &&
@@ -991,19 +992,19 @@ xfs_file_iomap_begin(
 
 		/* may drop and re-acquire the ilock */
 		error = xfs_reflink_allocate_cow(ip, &imap, &shared, &lockmode,
-						 flags);
+				directio);
 		if (error)
 			goto out_unlock;
 
 		/*
 		 * For buffered writes we need to report the address of the
 		 * previous block (if there was any) so that the higher level
-		 * write code can perform read-modify-write operations.  For
-		 * direct I/O code, which must be block aligned we need to
-		 * report the newly allocated address.
+		 * write code can perform read-modify-write operations; we
+		 * won't need the CoW fork mapping until writeback.  For direct
+		 * I/O, which must be block aligned, we need to report the
+		 * newly allocated address.
 		 */
-		if (!(flags & IOMAP_DIRECT) &&
-		    orig.br_startblock != HOLESTARTBLOCK)
+		if (!directio && orig.br_startblock != HOLESTARTBLOCK)
 			imap = orig;
 
 		end_fsb = imap.br_startoff + imap.br_blockcount;