NFSv4.1: send zero stateid seqid on v4.1 i/o

Data servers require a zero stateid seqid, and there is no advantage to not
doing the same for all NFSv4.1

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 94d50e8..a656b6e 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -1384,7 +1384,7 @@
 	hdr->replen += decode_putrootfh_maxsz;
 }
 
-static void encode_stateid(struct xdr_stream *xdr, const struct nfs_open_context *ctx, const struct nfs_lock_context *l_ctx)
+static void encode_stateid(struct xdr_stream *xdr, const struct nfs_open_context *ctx, const struct nfs_lock_context *l_ctx, int zero_seqid)
 {
 	nfs4_stateid stateid;
 	__be32 *p;
@@ -1392,6 +1392,8 @@
 	p = reserve_space(xdr, NFS4_STATEID_SIZE);
 	if (ctx->state != NULL) {
 		nfs4_copy_stateid(&stateid, ctx->state, l_ctx->lockowner, l_ctx->pid);
+		if (zero_seqid)
+			stateid.stateid.seqid = 0;
 		xdr_encode_opaque_fixed(p, stateid.data, NFS4_STATEID_SIZE);
 	} else
 		xdr_encode_opaque_fixed(p, zero_stateid.data, NFS4_STATEID_SIZE);
@@ -1404,7 +1406,8 @@
 	p = reserve_space(xdr, 4);
 	*p = cpu_to_be32(OP_READ);
 
-	encode_stateid(xdr, args->context, args->lock_context);
+	encode_stateid(xdr, args->context, args->lock_context,
+		       hdr->minorversion);
 
 	p = reserve_space(xdr, 12);
 	p = xdr_encode_hyper(p, args->offset);
@@ -1592,7 +1595,8 @@
 	p = reserve_space(xdr, 4);
 	*p = cpu_to_be32(OP_WRITE);
 
-	encode_stateid(xdr, args->context, args->lock_context);
+	encode_stateid(xdr, args->context, args->lock_context,
+		       hdr->minorversion);
 
 	p = reserve_space(xdr, 16);
 	p = xdr_encode_hyper(p, args->offset);