SUNRPC: Fix a bug in rpcauth_lookup_credcache()

The hash bucket is for some reason always being set to zero.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

include/linux/sunrpc/auth.h

@@ -59,8 +59,8 @@ struct rpc_cred {
 /*
  * Client authentication handle
  */
-#define RPC_CREDCACHE_NR	8
-#define RPC_CREDCACHE_MASK	(RPC_CREDCACHE_NR - 1)
+#define RPC_CREDCACHE_HASHBITS	4
+#define RPC_CREDCACHE_NR	(1 << RPC_CREDCACHE_HASHBITS)
 struct rpc_cred_cache {
 	struct hlist_head	hashtable[RPC_CREDCACHE_NR];
 	spinlock_t		lock;

net/sunrpc/auth.c

@@ -11,6 +11,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/errno.h>
+#include <linux/hash.h>
 #include <linux/sunrpc/clnt.h>
 #include <linux/spinlock.h>
 
@@ -280,7 +281,9 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
 	struct hlist_node *pos;
 	struct rpc_cred	*cred = NULL,
 			*entry, *new;
-	int		nr = 0;
+	unsigned int nr;
+
+	nr = hash_long(acred->uid, RPC_CREDCACHE_HASHBITS);
 
 	if (!(flags & RPCAUTH_LOOKUP_ROOTCREDS))
 		nr = acred->uid & RPC_CREDCACHE_MASK;