NFS: Simplify logic to compare socket addresses in client.c

Callback requests from IPv4 servers are now always guaranteed to be
AF_INET, and never mapped IPv4 AF_INET6 addresses.  Both
nfs_match_client() and nfs_find_client() can now share the same
address comparison logic, so fold them together.

We can also dispense with of most of the conditional compilation
in here.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 574158ae2398aaeb1151d76f0a85f2b73871b976..855daac0f246ad56759bede61000d6e29d1fb857 100644 (file)
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -224,38 +224,6 @@ void nfs_put_client(struct nfs_client *clp)
 }
 
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-static const struct in6_addr *nfs_map_ipv4_addr(const struct sockaddr *sa, struct in6_addr *addr_mapped)
-{
-       switch (sa->sa_family) {
-               default:
-                       return NULL;
-               case AF_INET6:
-                       return &((const struct sockaddr_in6 *)sa)->sin6_addr;
-                       break;
-               case AF_INET:
-                       ipv6_addr_set_v4mapped(((const struct sockaddr_in *)sa)->sin_addr.s_addr,
-                                       addr_mapped);
-                       return addr_mapped;
-       }
-}
-
-static int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
-               const struct sockaddr *sa2)
-{
-       const struct in6_addr *addr1;
-       const struct in6_addr *addr2;
-       struct in6_addr addr1_mapped;
-       struct in6_addr addr2_mapped;
-
-       addr1 = nfs_map_ipv4_addr(sa1, &addr1_mapped);
-       if (likely(addr1 != NULL)) {
-               addr2 = nfs_map_ipv4_addr(sa2, &addr2_mapped);
-               if (likely(addr2 != NULL))
-                       return ipv6_addr_equal(addr1, addr2);
-       }
-       return 0;
-}
-
 /*
  * Test if two ip6 socket addresses refer to the same socket by
  * comparing relevant fields. The padding bytes specifically, are not
@@ -267,38 +235,21 @@ static int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
  *
  * The caller should ensure both socket addresses are AF_INET6.
  */
-static int nfs_sockaddr_cmp_ip6(const struct sockaddr *sa1,
-                               const struct sockaddr *sa2)
+static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
+                                     const struct sockaddr *sa2)
 {
-       const struct sockaddr_in6 *saddr1 = (const struct sockaddr_in6 *)sa1;
-       const struct sockaddr_in6 *saddr2 = (const struct sockaddr_in6 *)sa2;
+       const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
+       const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
 
-       if (!ipv6_addr_equal(&saddr1->sin6_addr,
-                            &saddr1->sin6_addr))
+       if (ipv6_addr_scope(&sin1->sin6_addr) == IPV6_ADDR_SCOPE_LINKLOCAL &&
+           sin1->sin6_scope_id != sin2->sin6_scope_id)
                return 0;
-       if (ipv6_addr_scope(&saddr1->sin6_addr) == IPV6_ADDR_SCOPE_LINKLOCAL &&
-           saddr1->sin6_scope_id != saddr2->sin6_scope_id)
-               return 0;
-       return saddr1->sin6_port == saddr2->sin6_port;
-}
-#else
-static int nfs_sockaddr_match_ipaddr4(const struct sockaddr_in *sa1,
-                                const struct sockaddr_in *sa2)
-{
-       return sa1->sin_addr.s_addr == sa2->sin_addr.s_addr;
-}
 
-static int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
-                                const struct sockaddr *sa2)
-{
-       if (unlikely(sa1->sa_family != AF_INET || sa2->sa_family != AF_INET))
-               return 0;
-       return nfs_sockaddr_match_ipaddr4((const struct sockaddr_in *)sa1,
-                       (const struct sockaddr_in *)sa2);
+       return ipv6_addr_equal(&sin1->sin6_addr, &sin1->sin6_addr);
 }
-
-static int nfs_sockaddr_cmp_ip6(const struct sockaddr * sa1,
-                               const struct sockaddr * sa2)
+#else  /* !defined(CONFIG_IPV6) && !defined(CONFIG_IPV6_MODULE) */
+static int nfs_sockaddr_match_ipaddr6(const struct sockaddr *sa1,
+                                     const struct sockaddr *sa2)
 {
        return 0;
 }
@@ -311,20 +262,57 @@ static int nfs_sockaddr_cmp_ip6(const struct sockaddr * sa1,
  *
  * The caller should ensure both socket addresses are AF_INET.
  */
+static int nfs_sockaddr_match_ipaddr4(const struct sockaddr *sa1,
+                                     const struct sockaddr *sa2)
+{
+       const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
+       const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
+
+       return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
+}
+
+static int nfs_sockaddr_cmp_ip6(const struct sockaddr *sa1,
+                               const struct sockaddr *sa2)
+{
+       const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sa1;
+       const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sa2;
+
+       return nfs_sockaddr_match_ipaddr6(sa1, sa2) &&
+               (sin1->sin6_port == sin2->sin6_port);
+}
+
 static int nfs_sockaddr_cmp_ip4(const struct sockaddr *sa1,
                                const struct sockaddr *sa2)
 {
-       const struct sockaddr_in *saddr1 = (const struct sockaddr_in *)sa1;
-       const struct sockaddr_in *saddr2 = (const struct sockaddr_in *)sa2;
+       const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
+       const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
 
-       if (saddr1->sin_addr.s_addr != saddr2->sin_addr.s_addr)
+       return nfs_sockaddr_match_ipaddr4(sa1, sa2) &&
+               (sin1->sin_port == sin2->sin_port);
+}
+
+/*
+ * Test if two socket addresses represent the same actual socket,
+ * by comparing (only) relevant fields, excluding the port number.
+ */
+static int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
+                                    const struct sockaddr *sa2)
+{
+       if (sa1->sa_family != sa2->sa_family)
                return 0;
-       return saddr1->sin_port == saddr2->sin_port;
+
+       switch (sa1->sa_family) {
+       case AF_INET:
+               return nfs_sockaddr_match_ipaddr4(sa1, sa2);
+       case AF_INET6:
+               return nfs_sockaddr_match_ipaddr6(sa1, sa2);
+       }
+       return 0;
 }
 
 /*
  * Test if two socket addresses represent the same actual socket,
- * by comparing (only) relevant fields.
+ * by comparing (only) relevant fields, including the port number.
  */
 static int nfs_sockaddr_cmp(const struct sockaddr *sa1,
                            const struct sockaddr *sa2)