[SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iph

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

1 files changed, 18 insertions, 32 deletions

diff --git a/net/ipv4/ipcomp.c b/net/ipv4/ipcomp.c
index aa704b88f014..8eb46064c525 100644
--- a/net/ipv4/ipcomp.c
+++ b/net/ipv4/ipcomp.c
@@ -43,21 +43,15 @@ static LIST_HEAD(ipcomp_tfms_list);
 
 static int ipcomp_decompress(struct xfrm_state *x, struct sk_buff *skb)
 {
-        int err, plen, dlen;
         struct ipcomp_data *ipcd = x->data;
-        u8 *start, *scratch;
-        struct crypto_comp *tfm;
-        int cpu;
-
-        plen = skb->len;
-        dlen = IPCOMP_SCRATCH_SIZE;
-        start = skb->data;
+        const int plen = skb->len;
+        int dlen = IPCOMP_SCRATCH_SIZE;
+        const u8 *start = skb->data;
+        const int cpu = get_cpu();
+        u8 *scratch = *per_cpu_ptr(ipcomp_scratches, cpu);
+        struct crypto_comp *tfm = *per_cpu_ptr(ipcd->tfms, cpu);
+        int err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen);
 
-        cpu = get_cpu();
-        scratch = *per_cpu_ptr(ipcomp_scratches, cpu);
-        tfm = *per_cpu_ptr(ipcd->tfms, cpu);
-
-        err = crypto_comp_decompress(tfm, start, plen, scratch, &dlen);
         if (err)
                 goto out;
 
@@ -90,7 +84,7 @@ static int ipcomp_input(struct xfrm_state *x, struct sk_buff *skb)
         skb->ip_summed = CHECKSUM_NONE;
 
         /* Remove ipcomp header and decompress original payload */
-        iph = skb->nh.iph;
+        iph = ip_hdr(skb);
         ipch = (void *)skb->data;
         iph->protocol = ipch->nexthdr;
         skb->h.raw = skb->nh.raw + sizeof(*ipch);
@@ -103,23 +97,16 @@ out:
 
 static int ipcomp_compress(struct xfrm_state *x, struct sk_buff *skb)
 {
-        int err, plen, dlen, ihlen;
-        struct iphdr *iph = skb->nh.iph;
         struct ipcomp_data *ipcd = x->data;
-        u8 *start, *scratch;
-        struct crypto_comp *tfm;
-        int cpu;
+        const int ihlen = ip_hdrlen(skb);
+        const int plen = skb->len - ihlen;
+        int dlen = IPCOMP_SCRATCH_SIZE;
+        u8 *start = skb->data + ihlen;
+        const int cpu = get_cpu();
+        u8 *scratch = *per_cpu_ptr(ipcomp_scratches, cpu);
+        struct crypto_comp *tfm = *per_cpu_ptr(ipcd->tfms, cpu);
+        int err = crypto_comp_compress(tfm, start, plen, scratch, &dlen);
 
-        ihlen = iph->ihl * 4;
-        plen = skb->len - ihlen;
-        dlen = IPCOMP_SCRATCH_SIZE;
-        start = skb->data + ihlen;
-
-        cpu = get_cpu();
-        scratch = *per_cpu_ptr(ipcomp_scratches, cpu);
-        tfm = *per_cpu_ptr(ipcd->tfms, cpu);
-
-        err = crypto_comp_compress(tfm, start, plen, scratch, &dlen);
         if (err)
                 goto out;
 
@@ -142,12 +129,11 @@ out:
 static int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb)
 {
         int err;
-        struct iphdr *iph;
         struct ip_comp_hdr *ipch;
         struct ipcomp_data *ipcd = x->data;
         int hdr_len = 0;
+        struct iphdr *iph = ip_hdr(skb);
 
-        iph = skb->nh.iph;
         iph->tot_len = htons(skb->len);
         hdr_len = iph->ihl * 4;
         if ((skb->len - hdr_len) < ipcd->threshold) {
@@ -159,7 +145,7 @@ static int ipcomp_output(struct xfrm_state *x, struct sk_buff *skb)
                 goto out_ok;
 
         err = ipcomp_compress(x, skb);
-        iph = skb->nh.iph;
+        iph = ip_hdr(skb);
 
         if (err) {
                 goto out_ok;