list_for_each_rcu must die: networking

All uses of list_for_each_rcu() can be profitably replaced by the
easier-to-use list_for_each_entry_rcu().  This patch makes this change for
networking, in preparation for removing the list_for_each_rcu() API
entirely.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 7 insertions, 15 deletions

diff --git a/net/802/psnap.c b/net/802/psnap.c
index ea4643931446..b3cfe5a14fca 100644
--- a/net/802/psnap.c
+++ b/net/802/psnap.c
@@ -31,11 +31,9 @@ static struct llc_sap *snap_sap;
  */
 static struct datalink_proto *find_snap_client(unsigned char *desc)
 {
-        struct list_head *entry;
         struct datalink_proto *proto = NULL, *p;
 
-        list_for_each_rcu(entry, &snap_list) {
-                p = list_entry(entry, struct datalink_proto, node);
+        list_for_each_entry_rcu(p, &snap_list, node) {
                 if (!memcmp(p->type, desc, 5)) {
                         proto = p;
                         break;
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index dd919d84285f..f440a9f54924 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -264,7 +264,6 @@ static inline int inet_netns_ok(struct net *net, int protocol)
 static int inet_create(struct net *net, struct socket *sock, int protocol)
 {
         struct sock *sk;
-        struct list_head *p;
         struct inet_protosw *answer;
         struct inet_sock *inet;
         struct proto *answer_prot;
@@ -281,13 +280,12 @@ static int inet_create(struct net *net, struct socket *sock, int protocol)
         sock->state = SS_UNCONNECTED;
 
         /* Look for the requested type/protocol pair. */
-        answer = NULL;
 lookup_protocol:
         err = -ESOCKTNOSUPPORT;
         rcu_read_lock();
-        list_for_each_rcu(p, &inetsw[sock->type]) {
-                answer = list_entry(p, struct inet_protosw, list);
+        list_for_each_entry_rcu(answer, &inetsw[sock->type], list) {
 
+                err = 0;
                 /* Check the non-wild match. */
                 if (protocol == answer->protocol) {
                         if (protocol != IPPROTO_IP)
@@ -302,10 +300,9 @@ lookup_protocol:
                                 break;
                 }
                 err = -EPROTONOSUPPORT;
-                answer = NULL;
         }
 
-        if (unlikely(answer == NULL)) {
+        if (unlikely(err)) {
                 if (try_loading_module < 2) {
                         rcu_read_unlock();
                         /*
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 3d828bc4b1cf..60461ad7fa6f 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -83,7 +83,6 @@ static int inet6_create(struct net *net, struct socket *sock, int protocol)
         struct inet_sock *inet;
         struct ipv6_pinfo *np;
         struct sock *sk;
-        struct list_head *p;
         struct inet_protosw *answer;
         struct proto *answer_prot;
         unsigned char answer_flags;
@@ -97,13 +96,12 @@ static int inet6_create(struct net *net, struct socket *sock, int protocol)
                 build_ehash_secret();
 
         /* Look for the requested type/protocol pair. */
-        answer = NULL;
 lookup_protocol:
         err = -ESOCKTNOSUPPORT;
         rcu_read_lock();
-        list_for_each_rcu(p, &inetsw6[sock->type]) {
-                answer = list_entry(p, struct inet_protosw, list);
+        list_for_each_entry_rcu(answer, &inetsw6[sock->type], list) {
 
+                err = 0;
                 /* Check the non-wild match. */
                 if (protocol == answer->protocol) {
                         if (protocol != IPPROTO_IP)
@@ -118,10 +116,9 @@ lookup_protocol:
                                 break;
                 }
                 err = -EPROTONOSUPPORT;
-                answer = NULL;
         }
 
-        if (!answer) {
+        if (err) {
                 if (try_loading_module < 2) {
                         rcu_read_unlock();
                         /*