[PATCH 5.10 077/306] NFSv4/pnfs: The layout barrier indicate a minimal value for the seqid

From: Greg Kroah-Hartman
Date: Thu Sep 16 2021 - 12:18:51 EST


From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>

[ Upstream commit d6236a98b3bab07c0a1455fd1ab46f79c3978cdc ]

The intention of the layout barrier is to ensure that we do not update
the layout to match an older value than the current expectation. Fix the
test in pnfs_layout_stateid_blocked() to reflect that it is legal for
the seqid of the stateid to match that of the barrier.

Fixes: aa95edf309ef ("NFSv4/pnfs: Fix the layout barrier update")
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/nfs/pnfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 741b6283ac9c..5370e082aded 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1004,7 +1004,7 @@ pnfs_layout_stateid_blocked(const struct pnfs_layout_hdr *lo,
{
u32 seqid = be32_to_cpu(stateid->seqid);

- return !pnfs_seqid_is_newer(seqid, lo->plh_barrier) && lo->plh_barrier;
+ return lo->plh_barrier && pnfs_seqid_is_newer(lo->plh_barrier, seqid);
}

/* lget is set to 1 if called from inside send_layoutget call chain */
--
2.30.2