5 files changed, 61 insertions, 3 deletions

diff --git a/include/linux/sunrpc/cache.h b/include/linux/sunrpc/cache.h
index b5612c9..3699dff 100644
--- a/include/linux/sunrpc/cache.h
+++ b/include/linux/sunrpc/cache.h
@@ -163,6 +163,17 @@ static inline void cache_put(struct cache_head *h, struct cache_detail *cd)
 	kref_put(&h->ref, cd->cache_put);
 }
 
+static inline int cache_valid(struct cache_head *h)
+{
+	/* If an item has been unhashed pending removal when
+	 * the refcount drops to 0, the expiry_time will be
+	 * set to 0.  We don't want to consider such items
+	 * valid in this context even though CACHE_VALID is
+	 * set.
+	 */
+	return (h->expiry_time != 0 && test_bit(CACHE_VALID, &h->flags));
+}
+
 extern int cache_check(struct cache_detail *detail,
 		       struct cache_head *h, struct cache_req *rqstp);
 extern void cache_flush(void);
diff --git a/include/linux/sunrpc/svcauth.h b/include/linux/sunrpc/svcauth.h
index a660165..de92619 100644
--- a/include/linux/sunrpc/svcauth.h
+++ b/include/linux/sunrpc/svcauth.h
@@ -126,6 +126,7 @@ extern struct auth_domain *auth_domain_find(char *name);
 extern struct auth_domain *auth_unix_lookup(struct in_addr addr);
 extern int auth_unix_forget_old(struct auth_domain *dom);
 extern void svcauth_unix_purge(void);
+extern void svcauth_unix_info_release(void *);
 
 static inline unsigned long hash_str(char *name, int bits)
 {
diff --git a/include/linux/sunrpc/svcsock.h b/include/linux/sunrpc/svcsock.h
index 4c29615..98b21ad 100644
--- a/include/linux/sunrpc/svcsock.h
+++ b/include/linux/sunrpc/svcsock.h
@@ -54,6 +54,9 @@ struct svc_sock {
 	int			sk_reclen;	/* length of record */
 	int			sk_tcplen;	/* current read length */
 	time_t			sk_lastrecv;	/* time of last received request */
+
+	/* cache of various info for TCP sockets */
+	void			*sk_info_authunix;
 };
 
 /*
diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index 40d41a2..e1bd933 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -9,6 +9,7 @@
 #include <linux/seq_file.h>
 #include <linux/hash.h>
 #include <linux/string.h>
+#include <net/sock.h>
 
 #define RPCDBG_FACILITY	RPCDBG_AUTH
 
@@ -375,6 +376,44 @@ void svcauth_unix_purge(void)
 	cache_purge(&ip_map_cache);
 }
 
+static inline struct ip_map *
+ip_map_cached_get(struct svc_rqst *rqstp)
+{
+	struct ip_map *ipm = rqstp->rq_sock->sk_info_authunix;
+	if (ipm != NULL) {
+		if (!cache_valid(&ipm->h)) {
+			/*
+			 * The entry has been invalidated since it was
+			 * remembered, e.g. by a second mount from the
+			 * same IP address.
+			 */
+			rqstp->rq_sock->sk_info_authunix = NULL;
+			cache_put(&ipm->h, &ip_map_cache);
+			return NULL;
+		}
+		cache_get(&ipm->h);
+	}
+	return ipm;
+}
+
+static inline void
+ip_map_cached_put(struct svc_rqst *rqstp, struct ip_map *ipm)
+{
+	struct svc_sock *svsk = rqstp->rq_sock;
+
+	if (svsk->sk_sock->type == SOCK_STREAM && svsk->sk_info_authunix == NULL)
+		svsk->sk_info_authunix = ipm;	/* newly cached, keep the reference */
+	else
+		cache_put(&ipm->h, &ip_map_cache);
+}
+
+void
+svcauth_unix_info_release(void *info)
+{
+	struct ip_map *ipm = info;
+	cache_put(&ipm->h, &ip_map_cache);
+}
+
 static int
 svcauth_unix_set_client(struct svc_rqst *rqstp)
 {
@@ -384,8 +423,10 @@ svcauth_unix_set_client(struct svc_rqst *rqstp)
 	if (rqstp->rq_proc == 0)
 		return SVC_OK;
 
-	ipm = ip_map_lookup(rqstp->rq_server->sv_program->pg_class,
-			    rqstp->rq_addr.sin_addr);
+	ipm = ip_map_cached_get(rqstp);
+	if (ipm == NULL)
+		ipm = ip_map_lookup(rqstp->rq_server->sv_program->pg_class,
+				    rqstp->rq_addr.sin_addr);
 
 	if (ipm == NULL)
 		return SVC_DENIED;
@@ -400,7 +441,7 @@ svcauth_unix_set_client(struct svc_rqst *rqstp)
 		case 0:
 			rqstp->rq_client = &ipm->m_client->h;
 			kref_get(&rqstp->rq_client->ref);
-			cache_put(&ipm->h, &ip_map_cache);
+			ip_map_cached_put(rqstp, ipm);
 			break;
 	}
 	return SVC_OK;
diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index 1d512337..b39e7e2 100644
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -1610,6 +1610,8 @@ svc_delete_socket(struct svc_sock *svsk)
 			sockfd_put(svsk->sk_sock);
 		else
 			sock_release(svsk->sk_sock);
+		if (svsk->sk_info_authunix != NULL)
+			svcauth_unix_info_release(svsk->sk_info_authunix);
 		kfree(svsk);
 	} else {
 		spin_unlock_bh(&serv->sv_lock);