NFSv4: Kill braindead gcc warnings

nfs4_open_revalidate: 'res' may be used uninitialized
nfs4_callback_compound: ‘hdr_res.nops’ may be used uninitialized
			'op_nr’ may be used uninitialized
encode_getattr_res: ‘savep’ may be used uninitialized
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/callback_xdr.c

@@ -330,7 +330,7 @@ static unsigned encode_op_hdr(struct xdr_stream *xdr, uint32_t op, uint32_t res)
 
 static unsigned encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
 {
-	uint32_t *savep;
+	uint32_t *savep = NULL;
 	unsigned status = res->status;
 	
 	if (unlikely(status != 0))
@@ -358,23 +358,26 @@ static unsigned process_op(struct svc_rqst *rqstp,
 		struct xdr_stream *xdr_in, void *argp,
 		struct xdr_stream *xdr_out, void *resp)
 {
-	struct callback_op *op;
-	unsigned int op_nr;
+	struct callback_op *op = &callback_ops[0];
+	unsigned int op_nr = OP_CB_ILLEGAL;
 	unsigned int status = 0;
 	long maxlen;
 	unsigned res;
 
 	dprintk("%s: start\n", __FUNCTION__);
 	status = decode_op_hdr(xdr_in, &op_nr);
-	if (unlikely(status != 0)) {
-		op_nr = OP_CB_ILLEGAL;
-		op = &callback_ops[0];
-	} else if (unlikely(op_nr != OP_CB_GETATTR && op_nr != OP_CB_RECALL)) {
-		op_nr = OP_CB_ILLEGAL;
-		op = &callback_ops[0];
-		status = htonl(NFS4ERR_OP_ILLEGAL);
-	} else
-		op = &callback_ops[op_nr];
+	if (likely(status == 0)) {
+		switch (op_nr) {
+			case OP_CB_GETATTR:
+			case OP_CB_RECALL:
+				op = &callback_ops[op_nr];
+				break;
+			default:
+				op_nr = OP_CB_ILLEGAL;
+				op = &callback_ops[0];
+				status = htonl(NFS4ERR_OP_ILLEGAL);
+		}
+	}
 
 	maxlen = xdr_out->end - xdr_out->p;
 	if (maxlen > 0 && maxlen < PAGE_SIZE) {
@@ -416,6 +419,7 @@ static int nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp
 	decode_compound_hdr_arg(&xdr_in, &hdr_arg);
 	hdr_res.taglen = hdr_arg.taglen;
 	hdr_res.tag = hdr_arg.tag;
+	hdr_res.nops = NULL;
 	encode_compound_hdr_res(&xdr_out, &hdr_res);
 
 	for (;;) {

fs/nfs/nfs4proc.c

@@ -908,7 +908,7 @@ static int _nfs4_open_delegated(struct inode *inode, int flags, struct rpc_cred
 static struct nfs4_state *nfs4_open_delegated(struct inode *inode, int flags, struct rpc_cred *cred)
 {
 	struct nfs4_exception exception = { };
-	struct nfs4_state *res;
+	struct nfs4_state *res = ERR_PTR(-EIO);
 	int err;
 
 	do {