[IP]: Introduce ip_hdrlen()

For the common sequence "skb->nh.iph->ihl * 4", removing a good number of open
coded skb->nh.iph uses, now to go after the rest...

Just out of curiosity, here are the idioms found to get the same result:

skb->nh.iph->ihl << 2
skb->nh.iph->ihl<<2
skb->nh.iph->ihl * 4
skb->nh.iph->ihl*4
(skb->nh.iph)->ihl * sizeof(u32)

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 14 insertions, 17 deletions

diff --git a/net/ipv4/ipvs/ip_vs_app.c b/net/ipv4/ipvs/ip_vs_app.c
index f29d3a27eec6..e5beab28cd0f 100644
--- a/net/ipv4/ipvs/ip_vs_app.c
+++ b/net/ipv4/ipvs/ip_vs_app.c
@@ -331,7 +331,7 @@ static inline int app_tcp_pkt_out(struct ip_vs_conn *cp, struct sk_buff **pskb,
                                   struct ip_vs_app *app)
 {
         int diff;
-        unsigned int tcp_offset = (*pskb)->nh.iph->ihl*4;
+        const unsigned int tcp_offset = ip_hdrlen(*pskb);
         struct tcphdr *th;
         __u32 seq;
 
@@ -406,7 +406,7 @@ static inline int app_tcp_pkt_in(struct ip_vs_conn *cp, struct sk_buff **pskb,
                                  struct ip_vs_app *app)
 {
         int diff;
-        unsigned int tcp_offset = (*pskb)->nh.iph->ihl*4;
+        const unsigned int tcp_offset = ip_hdrlen(*pskb);
         struct tcphdr *th;
         __u32 seq;
 
diff --git a/net/ipv4/ipvs/ip_vs_core.c b/net/ipv4/ipvs/ip_vs_core.c
index 5d54dd2ce12f..7893c00a91fe 100644
--- a/net/ipv4/ipvs/ip_vs_core.c
+++ b/net/ipv4/ipvs/ip_vs_core.c
@@ -713,8 +713,7 @@ static inline int is_tcp_reset(const struct sk_buff *skb)
 {
         struct tcphdr _tcph, *th;
 
-        th = skb_header_pointer(skb, skb->nh.iph->ihl * 4,
-                                sizeof(_tcph), &_tcph);
+        th = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_tcph), &_tcph);
         if (th == NULL)
                 return 0;
         return th->rst;
diff --git a/net/ipv4/ipvs/ip_vs_proto_tcp.c b/net/ipv4/ipvs/ip_vs_proto_tcp.c
index 16a9ebee2fe6..e65382da713e 100644
--- a/net/ipv4/ipvs/ip_vs_proto_tcp.c
+++ b/net/ipv4/ipvs/ip_vs_proto_tcp.c
@@ -76,8 +76,7 @@ tcp_conn_schedule(struct sk_buff *skb,
         struct ip_vs_service *svc;
         struct tcphdr _tcph, *th;
 
-        th = skb_header_pointer(skb, skb->nh.iph->ihl*4,
-                                sizeof(_tcph), &_tcph);
+        th = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_tcph), &_tcph);
         if (th == NULL) {
                 *verdict = NF_DROP;
                 return 0;
@@ -127,7 +126,7 @@ tcp_snat_handler(struct sk_buff **pskb,
                  struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
 {
         struct tcphdr *tcph;
-        unsigned int tcphoff = (*pskb)->nh.iph->ihl * 4;
+        const unsigned int tcphoff = ip_hdrlen(*pskb);
 
         /* csum_check requires unshared skb */
         if (!ip_vs_make_skb_writable(pskb, tcphoff+sizeof(*tcph)))
@@ -175,7 +174,7 @@ tcp_dnat_handler(struct sk_buff **pskb,
                  struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
 {
         struct tcphdr *tcph;
-        unsigned int tcphoff = (*pskb)->nh.iph->ihl * 4;
+        const unsigned int tcphoff = ip_hdrlen(*pskb);
 
         /* csum_check requires unshared skb */
         if (!ip_vs_make_skb_writable(pskb, tcphoff+sizeof(*tcph)))
@@ -224,7 +223,7 @@ tcp_dnat_handler(struct sk_buff **pskb,
 static int
 tcp_csum_check(struct sk_buff *skb, struct ip_vs_protocol *pp)
 {
-        unsigned int tcphoff = skb->nh.iph->ihl*4;
+        const unsigned int tcphoff = ip_hdrlen(skb);
 
         switch (skb->ip_summed) {
         case CHECKSUM_NONE:
@@ -467,8 +466,7 @@ tcp_state_transition(struct ip_vs_conn *cp, int direction,
 {
         struct tcphdr _tcph, *th;
 
-        th = skb_header_pointer(skb, skb->nh.iph->ihl*4,
-                                sizeof(_tcph), &_tcph);
+        th = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_tcph), &_tcph);
         if (th == NULL)
                 return 0;
 
diff --git a/net/ipv4/ipvs/ip_vs_proto_udp.c b/net/ipv4/ipvs/ip_vs_proto_udp.c
index 03f0a414cfa4..2cd950638923 100644
--- a/net/ipv4/ipvs/ip_vs_proto_udp.c
+++ b/net/ipv4/ipvs/ip_vs_proto_udp.c
@@ -22,7 +22,7 @@
 #include <linux/udp.h>
 
 #include <net/ip_vs.h>
-
+#include <net/ip.h>
 
 static struct ip_vs_conn *
 udp_conn_in_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
@@ -56,7 +56,7 @@ udp_conn_out_get(const struct sk_buff *skb, struct ip_vs_protocol *pp,
         struct ip_vs_conn *cp;
         __be16 _ports[2], *pptr;
 
-        pptr = skb_header_pointer(skb, skb->nh.iph->ihl*4,
+        pptr = skb_header_pointer(skb, ip_hdrlen(skb),
                                   sizeof(_ports), _ports);
         if (pptr == NULL)
                 return NULL;
@@ -82,7 +82,7 @@ udp_conn_schedule(struct sk_buff *skb, struct ip_vs_protocol *pp,
         struct ip_vs_service *svc;
         struct udphdr _udph, *uh;
 
-        uh = skb_header_pointer(skb, skb->nh.iph->ihl*4,
+        uh = skb_header_pointer(skb, ip_hdrlen(skb),
                                 sizeof(_udph), &_udph);
         if (uh == NULL) {
                 *verdict = NF_DROP;
@@ -133,7 +133,7 @@ udp_snat_handler(struct sk_buff **pskb,
                  struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
 {
         struct udphdr *udph;
-        unsigned int udphoff = (*pskb)->nh.iph->ihl * 4;
+        const unsigned int udphoff = ip_hdrlen(*pskb);
 
         /* csum_check requires unshared skb */
         if (!ip_vs_make_skb_writable(pskb, udphoff+sizeof(*udph)))
@@ -187,7 +187,7 @@ udp_dnat_handler(struct sk_buff **pskb,
                  struct ip_vs_protocol *pp, struct ip_vs_conn *cp)
 {
         struct udphdr *udph;
-        unsigned int udphoff = (*pskb)->nh.iph->ihl * 4;
+        unsigned int udphoff = ip_hdrlen(*pskb);
 
         /* csum_check requires unshared skb */
         if (!ip_vs_make_skb_writable(pskb, udphoff+sizeof(*udph)))
@@ -239,7 +239,7 @@ static int
 udp_csum_check(struct sk_buff *skb, struct ip_vs_protocol *pp)
 {
         struct udphdr _udph, *uh;
-        unsigned int udphoff = skb->nh.iph->ihl*4;
+        const unsigned int udphoff = ip_hdrlen(skb);
 
         uh = skb_header_pointer(skb, udphoff, sizeof(_udph), &_udph);
         if (uh == NULL)