[IPV6]: Move nfheader_len into rt6_info

The dst member nfheader_len is only used by IPv6.  It's also currently
creating a rather ugly alignment hole in struct dst.  Therefore this patch
moves it from there into struct rt6_info.

It also reorders the fields in rt6_info to minimize holes.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 13 insertions, 8 deletions

diff --git a/include/net/dst.h b/include/net/dst.h
index 2f65e894b829..69888f1502b1 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -50,7 +50,6 @@ struct dst_entry
         unsigned long           expires;
 
         unsigned short          header_len;     /* more space at head required */
-        unsigned short          nfheader_len;   /* more non-fragment space at head required */
         unsigned short          trailer_len;    /* space to reserve at tail */
 
         u32                     metrics[RTAX_MAX];
diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
index 857821360bb6..4cefcffe773e 100644
--- a/include/net/ip6_fib.h
+++ b/include/net/ip6_fib.h
@@ -99,16 +99,21 @@ struct rt6_info
         u32                             rt6i_flags;
         u32                             rt6i_metric;
         atomic_t                        rt6i_ref;
-        struct fib6_table               *rt6i_table;
 
-        struct rt6key                   rt6i_dst;
-        struct rt6key                   rt6i_src;
+        /* more non-fragment space at head required */
+        unsigned short                  nfheader_len;
 
         u8                              rt6i_protocol;
 
+        struct fib6_table               *rt6i_table;
+
+        struct rt6key                   rt6i_dst;
+
 #ifdef CONFIG_XFRM
         u32                             rt6i_flow_cache_genid;
 #endif
+
+        struct rt6key                   rt6i_src;
 };
 
 static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
index cc86fb110dd8..5ee3a2f9fb27 100644
--- a/net/ipv4/xfrm4_policy.c
+++ b/net/ipv4/xfrm4_policy.c
@@ -161,7 +161,6 @@ __xfrm4_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int
                 dst_prev->flags        |= DST_HOST;
                 dst_prev->lastuse       = jiffies;
                 dst_prev->header_len    = header_len;
-                dst_prev->nfheader_len  = 0;
                 dst_prev->trailer_len   = trailer_len;
                 memcpy(&dst_prev->metrics, &x->route->metrics, sizeof(dst_prev->metrics));
 
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 150615758fdc..387030d2483c 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1099,7 +1099,7 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
                 sk->sk_sndmsg_page = NULL;
                 sk->sk_sndmsg_off = 0;
                 exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0) -
-                            rt->u.dst.nfheader_len;
+                            rt->nfheader_len;
                 length += exthdrlen;
                 transhdrlen += exthdrlen;
         } else {
@@ -1114,7 +1114,8 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
 
         hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
 
-        fragheaderlen = sizeof(struct ipv6hdr) + rt->u.dst.nfheader_len + (opt ? opt->opt_nflen : 0);
+        fragheaderlen = sizeof(struct ipv6hdr) + rt->nfheader_len +
+                        (opt ? opt->opt_nflen : 0);
         maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr);
 
         if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index 3cad3e8dc4da..5b02f0efd38e 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -157,7 +157,8 @@ __xfrm6_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int
                 dst_prev = dst1;
 
                 if (xfrm[i]->type->flags & XFRM_TYPE_NON_FRAGMENT)
-                        dst->nfheader_len += xfrm[i]->props.header_len;
+                        ((struct rt6_info *)dst)->nfheader_len +=
+                                xfrm[i]->props.header_len;
                 header_len += xfrm[i]->props.header_len;
                 trailer_len += xfrm[i]->props.trailer_len;