ipv6: move csum_ipv6_magic() and udp6_csum_init() into static library

As suggested by David, udp6_csum_init() is too big to be inlined,
move it to ipv6 static library, net/ipv6/ip6_checksum.c.

And the generic csum_ipv6_magic() too.

Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 98 insertions, 35 deletions

diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index 4ea244891b58..309af19a0a0a 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -40,7 +40,7 @@ obj-$(CONFIG_IPV6_SIT) += sit.o
 obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
 obj-$(CONFIG_IPV6_GRE) += ip6_gre.o
 
-obj-y += addrconf_core.o exthdrs_core.o
+obj-y += addrconf_core.o exthdrs_core.o ip6_checksum.o
 obj-$(CONFIG_INET) += output_core.o protocol.o $(ipv6-offload)
 
 obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o
diff --git a/net/ipv6/ip6_checksum.c b/net/ipv6/ip6_checksum.c
new file mode 100644
index 000000000000..72d198b8e4d2
--- /dev/null
+++ b/net/ipv6/ip6_checksum.c
@@ -0,0 +1,97 @@
+#include <net/ip.h>
+#include <net/udp.h>
+#include <net/udplite.h>
+#include <asm/checksum.h>
+
+#ifndef _HAVE_ARCH_IPV6_CSUM
+__sum16 csum_ipv6_magic(const struct in6_addr *saddr,
+                        const struct in6_addr *daddr,
+                        __u32 len, unsigned short proto,
+                        __wsum csum)
+{
+
+        int carry;
+        __u32 ulen;
+        __u32 uproto;
+        __u32 sum = (__force u32)csum;
+
+        sum += (__force u32)saddr->s6_addr32[0];
+        carry = (sum < (__force u32)saddr->s6_addr32[0]);
+        sum += carry;
+
+        sum += (__force u32)saddr->s6_addr32[1];
+        carry = (sum < (__force u32)saddr->s6_addr32[1]);
+        sum += carry;
+
+        sum += (__force u32)saddr->s6_addr32[2];
+        carry = (sum < (__force u32)saddr->s6_addr32[2]);
+        sum += carry;
+
+        sum += (__force u32)saddr->s6_addr32[3];
+        carry = (sum < (__force u32)saddr->s6_addr32[3]);
+        sum += carry;
+
+        sum += (__force u32)daddr->s6_addr32[0];
+        carry = (sum < (__force u32)daddr->s6_addr32[0]);
+        sum += carry;
+
+        sum += (__force u32)daddr->s6_addr32[1];
+        carry = (sum < (__force u32)daddr->s6_addr32[1]);
+        sum += carry;
+
+        sum += (__force u32)daddr->s6_addr32[2];
+        carry = (sum < (__force u32)daddr->s6_addr32[2]);
+        sum += carry;
+
+        sum += (__force u32)daddr->s6_addr32[3];
+        carry = (sum < (__force u32)daddr->s6_addr32[3]);
+        sum += carry;
+
+        ulen = (__force u32)htonl((__u32) len);
+        sum += ulen;
+        carry = (sum < ulen);
+        sum += carry;
+
+        uproto = (__force u32)htonl(proto);
+        sum += uproto;
+        carry = (sum < uproto);
+        sum += carry;
+
+        return csum_fold((__force __wsum)sum);
+}
+EXPORT_SYMBOL(csum_ipv6_magic);
+#endif
+
+int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto)
+{
+        int err;
+
+        UDP_SKB_CB(skb)->partial_cov = 0;
+        UDP_SKB_CB(skb)->cscov = skb->len;
+
+        if (proto == IPPROTO_UDPLITE) {
+                err = udplite_checksum_init(skb, uh);
+                if (err)
+                        return err;
+        }
+
+        if (uh->check == 0) {
+                /* RFC 2460 section 8.1 says that we SHOULD log
+                   this error. Well, it is reasonable.
+                 */
+                LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
+                return 1;
+        }
+        if (skb->ip_summed == CHECKSUM_COMPLETE &&
+            !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
+                             skb->len, proto, skb->csum))
+                skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+        if (!skb_csum_unnecessary(skb))
+                skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
+                                                         &ipv6_hdr(skb)->daddr,
+                                                         skb->len, proto, 0));
+
+        return 0;
+}
+EXPORT_SYMBOL(udp6_csum_init);
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index dfaa29b8b293..1afb635d9b57 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -752,40 +752,6 @@ static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
         return 0;
 }
 
-static inline int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh,
-                                 int proto)
-{
-        int err;
-
-        UDP_SKB_CB(skb)->partial_cov = 0;
-        UDP_SKB_CB(skb)->cscov = skb->len;
-
-        if (proto == IPPROTO_UDPLITE) {
-                err = udplite_checksum_init(skb, uh);
-                if (err)
-                        return err;
-        }
-
-        if (uh->check == 0) {
-                /* RFC 2460 section 8.1 says that we SHOULD log
-                   this error. Well, it is reasonable.
-                 */
-                LIMIT_NETDEBUG(KERN_INFO "IPv6: udp checksum is 0\n");
-                return 1;
-        }
-        if (skb->ip_summed == CHECKSUM_COMPLETE &&
-            !csum_ipv6_magic(&ipv6_hdr(skb)->saddr, &ipv6_hdr(skb)->daddr,
-                             skb->len, proto, skb->csum))
-                skb->ip_summed = CHECKSUM_UNNECESSARY;
-
-        if (!skb_csum_unnecessary(skb))
-                skb->csum = ~csum_unfold(csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
-                                                         &ipv6_hdr(skb)->daddr,
-                                                         skb->len, proto, 0));
-
-        return 0;
-}
-
 int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
                    int proto)
 {