NFSv4.1: keep seq_res.sr_slot as pointer rather than an index

Having to explicitly initialize sr_slotid to NFS4_MAX_SLOT_TABLE
resulted in numerous bugs.  Keeping the current slot as a pointer
to the slot table is more straight forward and robust as it's
implicitly set up to NULL wherever the seq_res member is initialized
to zeroes.

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 172df83..5772b2c 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -170,7 +170,7 @@
 
 struct nfs4_sequence_res {
 	struct nfs4_session	*sr_session;
-	u8			sr_slotid;	/* slot used to send request */
+	struct nfs4_slot	*sr_slot;	/* slot used to send request */
 	int			sr_status;	/* sequence operation status */
 	unsigned long		sr_renewal_time;
 	u32			sr_status_flags;