xfrm: store xfrm_mode directly, not its address

This structure is now only 4 bytes, so its more efficient
to cache a copy rather than its address.

No significant size difference in allmodconfig vmlinux.

With non-modular kernel that has all XFRM options enabled, this
series reduces vmlinux image size by ~11kb. All xfrm_mode
indirections are gone and all modes are built-in.

before (ipsec-next master):
    text      data      bss         dec   filename
21071494   7233140 11104324    39408958   vmlinux.master

after this series:
21066448   7226772 11104324    39397544   vmlinux.patched

With allmodconfig kernel, the size increase is only 362 bytes,
even all the xfrm config options removed in this series are
modular.

before:
    text      data     bss      dec   filename
15731286   6936912 4046908 26715106   vmlinux.master

after this series:
15731492   6937068  4046908  26715468 vmlinux

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

6 files changed, 32 insertions, 32 deletions

diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c
index a20f376fe71f..b24cd86a02c3 100644
--- a/net/xfrm/xfrm_device.c
+++ b/net/xfrm/xfrm_device.c
@@ -53,20 +53,20 @@ static void __xfrm_mode_tunnel_prep(struct xfrm_state *x, struct sk_buff *skb,
 /* Adjust pointers into the packet when IPsec is done at layer2 */
 static void xfrm_outer_mode_prep(struct xfrm_state *x, struct sk_buff *skb)
 {
-        switch (x->outer_mode->encap) {
+        switch (x->outer_mode.encap) {
         case XFRM_MODE_TUNNEL:
-                if (x->outer_mode->family == AF_INET)
+                if (x->outer_mode.family == AF_INET)
                         return __xfrm_mode_tunnel_prep(x, skb,
                                                        sizeof(struct iphdr));
-                if (x->outer_mode->family == AF_INET6)
+                if (x->outer_mode.family == AF_INET6)
                         return __xfrm_mode_tunnel_prep(x, skb,
                                                        sizeof(struct ipv6hdr));
                 break;
         case XFRM_MODE_TRANSPORT:
-                if (x->outer_mode->family == AF_INET)
+                if (x->outer_mode.family == AF_INET)
                         return __xfrm_transport_prep(x, skb,
                                                      sizeof(struct iphdr));
-                if (x->outer_mode->family == AF_INET6)
+                if (x->outer_mode.family == AF_INET6)
                         return __xfrm_transport_prep(x, skb,
                                                      sizeof(struct ipv6hdr));
                 break;
diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index b5a31c8e2088..314973aaa414 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -351,12 +351,12 @@ xfrm_inner_mode_encap_remove(struct xfrm_state *x,
 
 static int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb)
 {
-        const struct xfrm_mode *inner_mode = x->inner_mode;
+        const struct xfrm_mode *inner_mode = &x->inner_mode;
         const struct xfrm_state_afinfo *afinfo;
         int err = -EAFNOSUPPORT;
 
         rcu_read_lock();
-        afinfo = xfrm_state_afinfo_get_rcu(x->outer_mode->family);
+        afinfo = xfrm_state_afinfo_get_rcu(x->outer_mode.family);
         if (likely(afinfo))
                 err = afinfo->extract_input(x, skb);
 
@@ -482,7 +482,7 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
                         goto drop;
                 }
 
-                family = x->outer_mode->family;
+                family = x->outer_mode.family;
 
                 /* An encap_type of -1 indicates async resumption. */
                 if (encap_type == -1) {
@@ -666,7 +666,7 @@ resume:
 
                 XFRM_MODE_SKB_CB(skb)->protocol = nexthdr;
 
-                inner_mode = x->inner_mode;
+                inner_mode = &x->inner_mode;
 
                 if (x->sel.family == AF_UNSPEC) {
                         inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
@@ -681,7 +681,7 @@ resume:
                         goto drop;
                 }
 
-                if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) {
+                if (x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL) {
                         decaps = 1;
                         break;
                 }
@@ -691,7 +691,7 @@ resume:
                  * transport mode so the outer address is identical.
                  */
                 daddr = &x->id.daddr;
-                family = x->outer_mode->family;
+                family = x->outer_mode.family;
 
                 err = xfrm_parse_spi(skb, nexthdr, &spi, &seq);
                 if (err < 0) {
@@ -721,7 +721,7 @@ resume:
 
                 err = -EAFNOSUPPORT;
                 rcu_read_lock();
-                afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode->family);
+                afinfo = xfrm_state_afinfo_get_rcu(x->inner_mode.family);
                 if (likely(afinfo))
                         err = afinfo->transport_finish(skb, xfrm_gro || async);
                 rcu_read_unlock();
diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c
index 4fc49dbf3edf..b9f118530db6 100644
--- a/net/xfrm/xfrm_interface.c
+++ b/net/xfrm/xfrm_interface.c
@@ -273,7 +273,7 @@ static int xfrmi_rcv_cb(struct sk_buff *skb, int err)
         xnet = !net_eq(xi->net, dev_net(skb->dev));
 
         if (xnet) {
-                inner_mode = x->inner_mode;
+                inner_mode = &x->inner_mode;
 
                 if (x->sel.family == AF_UNSPEC) {
                         inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol);
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 3cb2a328a8ab..a55510f9ff35 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -334,7 +334,7 @@ static int xfrm4_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
         IPCB(skb)->flags |= IPSKB_XFRM_TUNNEL_SIZE;
         skb->protocol = htons(ETH_P_IP);
 
-        switch (x->outer_mode->encap) {
+        switch (x->outer_mode.encap) {
         case XFRM_MODE_BEET:
                 return xfrm4_beet_encap_add(x, skb);
         case XFRM_MODE_TUNNEL:
@@ -357,7 +357,7 @@ static int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
         skb->ignore_df = 1;
         skb->protocol = htons(ETH_P_IPV6);
 
-        switch (x->outer_mode->encap) {
+        switch (x->outer_mode.encap) {
         case XFRM_MODE_BEET:
                 return xfrm6_beet_encap_add(x, skb);
         case XFRM_MODE_TUNNEL:
@@ -373,22 +373,22 @@ static int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb)
 
 static int xfrm_outer_mode_output(struct xfrm_state *x, struct sk_buff *skb)
 {
-        switch (x->outer_mode->encap) {
+        switch (x->outer_mode.encap) {
         case XFRM_MODE_BEET:
         case XFRM_MODE_TUNNEL:
-                if (x->outer_mode->family == AF_INET)
+                if (x->outer_mode.family == AF_INET)
                         return xfrm4_prepare_output(x, skb);
-                if (x->outer_mode->family == AF_INET6)
+                if (x->outer_mode.family == AF_INET6)
                         return xfrm6_prepare_output(x, skb);
                 break;
         case XFRM_MODE_TRANSPORT:
-                if (x->outer_mode->family == AF_INET)
+                if (x->outer_mode.family == AF_INET)
                         return xfrm4_transport_output(x, skb);
-                if (x->outer_mode->family == AF_INET6)
+                if (x->outer_mode.family == AF_INET6)
                         return xfrm6_transport_output(x, skb);
                 break;
         case XFRM_MODE_ROUTEOPTIMIZATION:
-                if (x->outer_mode->family == AF_INET6)
+                if (x->outer_mode.family == AF_INET6)
                         return xfrm6_ro_output(x, skb);
                 WARN_ON_ONCE(1);
                 break;
@@ -489,7 +489,7 @@ resume:
                 }
                 skb_dst_set(skb, dst);
                 x = dst->xfrm;
-        } while (x && !(x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL));
+        } while (x && !(x->outer_mode.flags & XFRM_MODE_FLAG_TUNNEL));
 
         return 0;
 
@@ -626,7 +626,7 @@ static int xfrm_inner_extract_output(struct xfrm_state *x, struct sk_buff *skb)
                 inner_mode = xfrm_ip2inner_mode(x,
                                 xfrm_af2proto(skb_dst(skb)->ops->family));
         else
-                inner_mode = x->inner_mode;
+                inner_mode = &x->inner_mode;
 
         if (inner_mode == NULL)
                 return -EAFNOSUPPORT;
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 1a5fd2296556..16e70fc547b1 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2595,7 +2595,7 @@ static struct dst_entry *xfrm_bundle_create(struct xfrm_policy *policy,
                                 goto put_states;
                         }
                 } else
-                        inner_mode = xfrm[i]->inner_mode;
+                        inner_mode = &xfrm[i]->inner_mode;
 
                 xdst->route = dst;
                 dst_copy_metrics(dst1, dst);
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index ace26f6dc790..d3d87c409f44 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -551,8 +551,6 @@ struct xfrm_state *xfrm_state_alloc(struct net *net)
                 x->lft.hard_packet_limit = XFRM_INF;
                 x->replay_maxage = 0;
                 x->replay_maxdiff = 0;
-                x->inner_mode = NULL;
-                x->inner_mode_iaf = NULL;
                 spin_lock_init(&x->lock);
         }
         return x;
@@ -2204,8 +2202,9 @@ int xfrm_state_mtu(struct xfrm_state *x, int mtu)
 
 int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
 {
-        const struct xfrm_mode *inner_mode;
         const struct xfrm_state_afinfo *afinfo;
+        const struct xfrm_mode *inner_mode;
+        const struct xfrm_mode *outer_mode;
         int family = x->props.family;
         int err;
 
@@ -2234,7 +2233,7 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
                     family != x->sel.family)
                         goto error;
 
-                x->inner_mode = inner_mode;
+                x->inner_mode = *inner_mode;
         } else {
                 const struct xfrm_mode *inner_mode_iaf;
                 int iafamily = AF_INET;
@@ -2246,7 +2245,7 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
                 if (!(inner_mode->flags & XFRM_MODE_FLAG_TUNNEL))
                         goto error;
 
-                x->inner_mode = inner_mode;
+                x->inner_mode = *inner_mode;
 
                 if (x->props.family == AF_INET)
                         iafamily = AF_INET6;
@@ -2254,7 +2253,7 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
                 inner_mode_iaf = xfrm_get_mode(x->props.mode, iafamily);
                 if (inner_mode_iaf) {
                         if (inner_mode_iaf->flags & XFRM_MODE_FLAG_TUNNEL)
-                                x->inner_mode_iaf = inner_mode_iaf;
+                                x->inner_mode_iaf = *inner_mode_iaf;
                 }
         }
 
@@ -2268,12 +2267,13 @@ int __xfrm_init_state(struct xfrm_state *x, bool init_replay, bool offload)
         if (err)
                 goto error;
 
-        x->outer_mode = xfrm_get_mode(x->props.mode, family);
-        if (x->outer_mode == NULL) {
+        outer_mode = xfrm_get_mode(x->props.mode, family);
+        if (!outer_mode) {
                 err = -EPROTONOSUPPORT;
                 goto error;
         }
 
+        x->outer_mode = *outer_mode;
         if (init_replay) {
                 err = xfrm_init_replay(x);
                 if (err)