xfs: set the unwritten bit in rmap lookup flags in xchk_bmap_get_rmapextents

stable inclusion
from linux-4.19.158
commit 5fda0976e88dd4addc401af6b2ab53b2842e47a6

--------------------------------

[ Upstream commit 5dda3897 ]

When the bmbt scrubber is looking up rmap extents, we need to set the
extent flags from the bmbt record fully.  This will matter once we fix
the rmap btree comparison functions to check those flags correctly.

Fixes: d852657c ("xfs: cross-reference reverse-mapping btree")
Signed-off-by: NDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NCheng Jian <cj.chengjian@huawei.com>

fs/xfs/scrub/bmap.c

@@ -102,6 +102,8 @@ xchk_bmap_get_rmap(
 
 	if (info->whichfork == XFS_ATTR_FORK)
 		rflags |= XFS_RMAP_ATTR_FORK;
+	if (irec->br_state == XFS_EXT_UNWRITTEN)
+		rflags |= XFS_RMAP_UNWRITTEN;
 
 	/*
 	 * CoW staging extents are owned (on disk) by the refcountbt, so