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@xxxxxx> Reviewed-by: Dave Chinner <dchinner@xxxxxxxxxx> Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- 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 699bbb81b8a8..f7b8b1329ddd 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) { -- 2.20.1