SUNRPC: Make server side AUTH_UNIX use lockless lookups

Convert structs ip_map and unix_gid to use RCU protected lookups.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 8 insertions, 6 deletions

diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index 84cf39021a03..fb9041b92f72 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -97,6 +97,7 @@ struct ip_map {
         char                    m_class[8]; /* e.g. "nfsd" */
         struct in6_addr         m_addr;
         struct unix_domain      *m_client;
+        struct rcu_head         m_rcu;
 };
 
 static void ip_map_put(struct kref *kref)
@@ -107,7 +108,7 @@ static void ip_map_put(struct kref *kref)
         if (test_bit(CACHE_VALID, &item->flags) &&
             !test_bit(CACHE_NEGATIVE, &item->flags))
                 auth_domain_put(&im->m_client->h);
-        kfree(im);
+        kfree_rcu(im, m_rcu);
 }
 
 static inline int hash_ip6(const struct in6_addr *ip)
@@ -286,9 +287,9 @@ static struct ip_map *__ip_map_lookup(struct cache_detail *cd, char *class,
 
         strcpy(ip.m_class, class);
         ip.m_addr = *addr;
-        ch = sunrpc_cache_lookup(cd, &ip.h,
-                                 hash_str(class, IP_HASHBITS) ^
-                                 hash_ip6(addr));
+        ch = sunrpc_cache_lookup_rcu(cd, &ip.h,
+                                     hash_str(class, IP_HASHBITS) ^
+                                     hash_ip6(addr));
 
         if (ch)
                 return container_of(ch, struct ip_map, h);
@@ -418,6 +419,7 @@ struct unix_gid {
         struct cache_head       h;
         kuid_t                  uid;
         struct group_info       *gi;
+        struct rcu_head         rcu;
 };
 
 static int unix_gid_hash(kuid_t uid)
@@ -432,7 +434,7 @@ static void unix_gid_put(struct kref *kref)
         if (test_bit(CACHE_VALID, &item->flags) &&
             !test_bit(CACHE_NEGATIVE, &item->flags))
                 put_group_info(ug->gi);
-        kfree(ug);
+        kfree_rcu(ug, rcu);
 }
 
 static int unix_gid_match(struct cache_head *corig, struct cache_head *cnew)
@@ -625,7 +627,7 @@ static struct unix_gid *unix_gid_lookup(struct cache_detail *cd, kuid_t uid)
         struct cache_head *ch;
 
         ug.uid = uid;
-        ch = sunrpc_cache_lookup(cd, &ug.h, unix_gid_hash(uid));
+        ch = sunrpc_cache_lookup_rcu(cd, &ug.h, unix_gid_hash(uid));
         if (ch)
                 return container_of(ch, struct unix_gid, h);
         else