s390/qeth: extract helper for route validation

As follow-up to commit 0cd6783d3c7d ("s390/qeth: check dst entry before use"),
consolidate the dst_check() logic into a single helper and add a wrapper
around the cast type selection.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/s390/net/qeth_core.h b/drivers/s390/net/qeth_core.h
index c81d5ec..d354b39 100644 (file)
--- a/drivers/s390/net/qeth_core.h
+++ b/drivers/s390/net/qeth_core.h
@@ -25,6 +25,8 @@
 #include <linux/wait.h>
 #include <linux/workqueue.h>
 
+#include <net/dst.h>
+#include <net/ip6_fib.h>
 #include <net/ipv6.h>
 #include <net/if_inet6.h>
 #include <net/addrconf.h>
@@ -877,6 +879,17 @@ static inline int qeth_get_ether_cast_type(struct sk_buff *skb)
        return RTN_UNICAST;
 }
 
+static inline struct dst_entry *qeth_dst_check_rcu(struct sk_buff *skb, int ipv)
+{
+       struct dst_entry *dst = skb_dst(skb);
+       struct rt6_info *rt;
+
+       rt = (struct rt6_info *) dst;
+       if (dst)
+               dst = dst_check(dst, (ipv == 6) ? rt6_get_cookie(rt) : 0);
+       return dst;
+}
+
 static inline void qeth_rx_csum(struct qeth_card *card, struct sk_buff *skb,
                                u8 flags)
 {

diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 1535192..5bf5129 100644 (file)
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -32,7 +32,6 @@
 #include <net/route.h>
 #include <net/ipv6.h>
 #include <net/ip6_route.h>
-#include <net/ip6_fib.h>
 #include <net/iucv/af_iucv.h>
 #include <linux/hashtable.h>
 
@@ -1878,26 +1877,17 @@ static int qeth_l3_do_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
        return rc;
 }
 
-static int qeth_l3_get_cast_type(struct sk_buff *skb)
+static int qeth_l3_get_cast_type_rcu(struct sk_buff *skb, struct dst_entry *dst,
+                                    int ipv)
 {
-       int ipv = qeth_get_ip_version(skb);
        struct neighbour *n = NULL;
-       struct dst_entry *dst;
 
-       rcu_read_lock();
-       dst = skb_dst(skb);
-       if (dst) {
-               struct rt6_info *rt = (struct rt6_info *) dst;
-
-               dst = dst_check(dst, (ipv == 6) ? rt6_get_cookie(rt) : 0);
-               if (dst)
-                       n = dst_neigh_lookup_skb(dst, skb);
-       }
+       if (dst)
+               n = dst_neigh_lookup_skb(dst, skb);
 
        if (n) {
                int cast_type = n->type;
 
-               rcu_read_unlock();
                neigh_release(n);
                if ((cast_type == RTN_BROADCAST) ||
                    (cast_type == RTN_MULTICAST) ||
@@ -1905,7 +1895,6 @@ static int qeth_l3_get_cast_type(struct sk_buff *skb)
                        return cast_type;
                return RTN_UNICAST;
        }
-       rcu_read_unlock();
 
        /* no neighbour (eg AF_PACKET), fall back to target's IP address ... */
        switch (ipv) {
@@ -1923,6 +1912,20 @@ static int qeth_l3_get_cast_type(struct sk_buff *skb)
        }
 }
 
+static int qeth_l3_get_cast_type(struct sk_buff *skb)
+{
+       int ipv = qeth_get_ip_version(skb);
+       struct dst_entry *dst;
+       int cast_type;
+
+       rcu_read_lock();
+       dst = qeth_dst_check_rcu(skb, ipv);
+       cast_type = qeth_l3_get_cast_type_rcu(skb, dst, ipv);
+       rcu_read_unlock();
+
+       return cast_type;
+}
+
 static u8 qeth_l3_cast_type_to_flag(int cast_type)
 {
        if (cast_type == RTN_MULTICAST)
@@ -1987,27 +1990,17 @@ static void qeth_l3_fill_header(struct qeth_qdio_out_q *queue,
        }
 
        rcu_read_lock();
-       dst = skb_dst(skb);
+       dst = qeth_dst_check_rcu(skb, ipv);
 
        if (ipv == 4) {
-               struct rtable *rt;
-
-               if (dst)
-                       dst = dst_check(dst, 0);
-               rt = (struct rtable *) dst;
+               struct rtable *rt = (struct rtable *) dst;
 
                *((__be32 *) &hdr->hdr.l3.next_hop.ipv4.addr) = (rt) ?
                                rt_nexthop(rt, ip_hdr(skb)->daddr) :
                                ip_hdr(skb)->daddr;
        } else {
                /* IPv6 */
-               struct rt6_info *rt;
-
-               if (dst) {
-                       rt = (struct rt6_info *) dst;
-                       dst = dst_check(dst, rt6_get_cookie(rt));
-               }
-               rt = (struct rt6_info *) dst;
+               struct rt6_info *rt = (struct rt6_info *) dst;
 
                if (rt && !ipv6_addr_any(&rt->rt6i_gateway))
                        l3_hdr->next_hop.ipv6_addr = rt->rt6i_gateway;