NFSv4: Ensure DELEGRETURN returns attributes

 Upon return of a write delegation, the server will almost always bump the
 change attribute. Ensure that we pick up that change so that we don't
 invalidate our data cache unnecessarily.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index d2ee09b..66cc720 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -159,8 +159,6 @@
 {
 	int res = 0;
 
-	__nfs_revalidate_inode(NFS_SERVER(inode), inode);
-
 	res = nfs4_proc_delegreturn(inode, delegation->cred, &delegation->stateid);
 	nfs_free_delegation(delegation);
 	return res;
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index b334915..984ca34 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -2920,11 +2920,12 @@
 
 struct nfs4_delegreturndata {
 	struct nfs4_delegreturnargs args;
+	struct nfs4_delegreturnres res;
 	struct nfs_fh fh;
 	nfs4_stateid stateid;
 	struct rpc_cred *cred;
 	unsigned long timestamp;
-	const struct nfs_server *server;
+	struct nfs_fattr fattr;
 	int rpc_status;
 };
 
@@ -2934,8 +2935,10 @@
 	struct rpc_message msg = {
 		.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_DELEGRETURN],
 		.rpc_argp = &data->args,
+		.rpc_resp = &data->res,
 		.rpc_cred = data->cred,
 	};
+	nfs_fattr_init(data->res.fattr);
 	rpc_call_setup(task, &msg, 0);
 }
 
@@ -2944,7 +2947,7 @@
 	struct nfs4_delegreturndata *data = calldata;
 	data->rpc_status = task->tk_status;
 	if (data->rpc_status == 0)
-		renew_lease(data->server, data->timestamp);
+		renew_lease(data->res.server, data->timestamp);
 }
 
 static void nfs4_delegreturn_release(void *calldata)
@@ -2964,6 +2967,7 @@
 static int _nfs4_proc_delegreturn(struct inode *inode, struct rpc_cred *cred, const nfs4_stateid *stateid)
 {
 	struct nfs4_delegreturndata *data;
+	struct nfs_server *server = NFS_SERVER(inode);
 	struct rpc_task *task;
 	int status;
 
@@ -2972,11 +2976,13 @@
 		return -ENOMEM;
 	data->args.fhandle = &data->fh;
 	data->args.stateid = &data->stateid;
+	data->args.bitmask = server->attr_bitmask;
 	nfs_copy_fh(&data->fh, NFS_FH(inode));
 	memcpy(&data->stateid, stateid, sizeof(data->stateid));
+	data->res.fattr = &data->fattr;
+	data->res.server = server;
 	data->cred = get_rpccred(cred);
 	data->timestamp = jiffies;
-	data->server = NFS_SERVER(inode);
 	data->rpc_status = 0;
 
 	task = rpc_run_task(NFS_CLIENT(inode), RPC_TASK_ASYNC, &nfs4_delegreturn_ops, data);
@@ -2985,8 +2991,11 @@
 		return PTR_ERR(task);
 	}
 	status = nfs4_wait_for_completion_rpc_task(task);
-	if (status == 0)
+	if (status == 0) {
 		status = data->rpc_status;
+		if (status == 0)
+			nfs_post_op_update_inode(inode, &data->fattr);
+	}
 	rpc_release_task(task);
 	return status;
 }
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 5d6bda4..12be1d6 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -392,9 +392,11 @@
 				decode_getattr_maxsz)
 #define NFS4_enc_delegreturn_sz	(compound_encode_hdr_maxsz + \
 				encode_putfh_maxsz + \
-				encode_delegreturn_maxsz)
+				encode_delegreturn_maxsz + \
+				encode_getattr_maxsz)
 #define NFS4_dec_delegreturn_sz (compound_decode_hdr_maxsz + \
-				decode_delegreturn_maxsz)
+				decode_delegreturn_maxsz + \
+				decode_getattr_maxsz)
 #define NFS4_enc_getacl_sz	(compound_encode_hdr_maxsz + \
 				encode_putfh_maxsz + \
 				encode_getattr_maxsz)
@@ -1983,14 +1985,20 @@
 {
 	struct xdr_stream xdr;
 	struct compound_hdr hdr = {
-		.nops = 2,
+		.nops = 3,
 	};
 	int status;
 
 	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
 	encode_compound_hdr(&xdr, &hdr);
-	if ((status = encode_putfh(&xdr, args->fhandle)) == 0)
-		status = encode_delegreturn(&xdr, args->stateid);
+	status = encode_putfh(&xdr, args->fhandle);
+	if (status != 0)
+		goto out;
+	status = encode_delegreturn(&xdr, args->stateid);
+	if (status != 0)
+		goto out;
+	status = encode_getfattr(&xdr, args->bitmask);
+out:
 	return status;
 }
 
@@ -4184,7 +4192,7 @@
 /*
  * DELEGRETURN request
  */
-static int nfs4_xdr_dec_delegreturn(struct rpc_rqst *rqstp, uint32_t *p, void *dummy)
+static int nfs4_xdr_dec_delegreturn(struct rpc_rqst *rqstp, uint32_t *p, struct nfs4_delegreturnres *res)
 {
 	struct xdr_stream xdr;
 	struct compound_hdr hdr;
@@ -4192,11 +4200,14 @@
 
 	xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
 	status = decode_compound_hdr(&xdr, &hdr);
-	if (status == 0) {
-		status = decode_putfh(&xdr);
-		if (status == 0)
-			status = decode_delegreturn(&xdr);
-	}
+	if (status != 0)
+		goto out;
+	status = decode_putfh(&xdr);
+	if (status != 0)
+		goto out;
+	status = decode_delegreturn(&xdr);
+	decode_getfattr(&xdr, res->fattr, res->server);
+out:
 	return status;
 }