NFSv4.1: don't send COMMIT to ds for data sync writes

Based on consensus reached in Feb 2011 interim IETF meeting regarding
use of LAYOUTCOMMIT, it has been decided that a NFS_DATA_SYNC return
from a WRITE to data server should not initiate a COMMIT.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 55a8c3671233..92b4a6614fd3 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -474,7 +474,10 @@ nfs_clear_request_commit(struct nfs_page *req)
 static inline
 int nfs_write_need_commit(struct nfs_write_data *data)
 {
-        return data->verf.committed != NFS_FILE_SYNC;
+        if (data->verf.committed == NFS_DATA_SYNC)
+                return data->lseg == NULL;
+        else
+                return data->verf.committed != NFS_FILE_SYNC;
 }
 
 static inline