NFS add a simple sync nfs4_proc_commit after async COPY

A COPY with unstable write data needs a simple sync commit.
Filehandle value is gotten as a part of the inner loop so in
case of a reboot retry it should get the new value.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index f9a70aa..df5d322 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5137,6 +5137,40 @@ static void nfs4_proc_commit_setup(struct nfs_commit_data *data, struct rpc_mess
 	nfs4_state_protect(server->nfs_client, NFS_SP4_MACH_CRED_COMMIT, clnt, msg);
 }
 
+static int _nfs4_proc_commit(struct file *dst, struct nfs_commitargs *args,
+				struct nfs_commitres *res)
+{
+	struct inode *dst_inode = file_inode(dst);
+	struct nfs_server *server = NFS_SERVER(dst_inode);
+	struct rpc_message msg = {
+		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_COMMIT],
+		.rpc_argp = args,
+		.rpc_resp = res,
+	};
+
+	args->fh = NFS_FH(dst_inode);
+	return nfs4_call_sync(server->client, server, &msg,
+			&args->seq_args, &res->seq_res, 1);
+}
+
+int nfs4_proc_commit(struct file *dst, __u64 offset, __u32 count, struct nfs_commitres *res)
+{
+	struct nfs_commitargs args = {
+		.offset = offset,
+		.count = count,
+	};
+	struct nfs_server *dst_server = NFS_SERVER(file_inode(dst));
+	struct nfs4_exception exception = { };
+	int status;
+
+	do {
+		status = _nfs4_proc_commit(dst, &args, res);
+		status = nfs4_handle_exception(dst_server, status, &exception);
+	} while (exception.retry);
+
+	return status;
+}
+
 struct nfs4_renewdata {
 	struct nfs_client	*client;
 	unsigned long		timestamp;