5 files changed, 61 insertions, 3 deletions

diff --git a/include/linux/sunrpc/cache.h b/include/linux/sunrpc/cache.h
index b5612c958cce..3699dff7db8f 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 a6601650deeb..de92619b0826 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 4c296152cbfa..98b21ad370fd 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 40d41a2831d7..e1bd933629fe 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 1d512337ccd9..b39e7e2b648f 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);