From 05b30949f1aa8d797eb5c1cf7a24b9c4f8e82320 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Thu, 17 Oct 2019 13:12:04 -0700
Subject: [PATCH] xfs: set IOMAP_F_NEW more carefully
Don't set IOMAP_F_NEW if we COW over an existing allocated range, as
these aren't strictly new allocations. This is required to be able to
use IOMAP_F_NEW to zero newly allocated blocks, which is required for
the iomap code to fully support file systems that don't do delayed
allocations or use unwritten extents.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/xfs_iomap.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index 699bbb81b8a81..f7b8b1329ddd1 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -707,9 +707,12 @@ xfs_file_iomap_begin_delay(
* Flag newly allocated delalloc blocks with IOMAP_F_NEW so we punch
* them out if the write happens to fail.
*/
- iomap_flags |= IOMAP_F_NEW;
- trace_xfs_iomap_alloc(ip, offset, count, whichfork,
- whichfork == XFS_DATA_FORK ? &imap : &cmap);
+ if (whichfork == XFS_DATA_FORK) {
+ iomap_flags |= IOMAP_F_NEW;
+ trace_xfs_iomap_alloc(ip, offset, count, whichfork, &imap);
+ } else {
+ trace_xfs_iomap_alloc(ip, offset, count, whichfork, &cmap);
+ }
done:
if (whichfork == XFS_COW_FORK) {
if (imap.br_startoff > offset_fsb) {