net: gre: move GSO functions to gre_offload

Similarly to TCP/UDP offloading, move all related GRE functions to
gre_offload.c to make things more explicit and similar to the rest
of the code.

Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/gre.h b/include/net/gre.h
index a5a4ddf..57e4afd 100644 (file)
--- a/include/net/gre.h
+++ b/include/net/gre.h
@@ -32,6 +32,10 @@ struct gre_cisco_protocol {
 
 int gre_cisco_register(struct gre_cisco_protocol *proto);
 int gre_cisco_unregister(struct gre_cisco_protocol *proto);
+
+int gre_offload_init(void);
+void gre_offload_exit(void);
+
 void gre_build_header(struct sk_buff *skb, const struct tnl_ptk_info *tpi,
                      int hdr_len);
 struct sk_buff *gre_handle_offloads(struct sk_buff *skb, bool gre_csum);

diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index 86ded0b..4b81e91 100644 (file)
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_PROC_FS) += proc.o
 obj-$(CONFIG_IP_MULTIPLE_TABLES) += fib_rules.o
 obj-$(CONFIG_IP_MROUTE) += ipmr.o
 obj-$(CONFIG_NET_IPIP) += ipip.o
+gre-y := gre_demux.o gre_offload.o
 obj-$(CONFIG_NET_IPGRE_DEMUX) += gre.o
 obj-$(CONFIG_NET_IPGRE) += ip_gre.o
 obj-$(CONFIG_NET_IPVTI) += ip_vti.o

diff --git a/net/ipv4/gre.c b/net/ipv4/gre_demux.c
similarity index 79%
rename from net/ipv4/gre.c
rename to net/ipv4/gre_demux.c
index ba4803e..736c9fc 100644 (file)
--- a/net/ipv4/gre.c
+++ b/net/ipv4/gre_demux.c
@@ -334,113 +334,12 @@ static void gre_err(struct sk_buff *skb, u32 info)
        rcu_read_unlock();
 }
 
-static struct sk_buff *gre_gso_segment(struct sk_buff *skb,
-                                      netdev_features_t features)
-{
-       struct sk_buff *segs = ERR_PTR(-EINVAL);
-       netdev_features_t enc_features;
-       int ghl = GRE_HEADER_SECTION;
-       struct gre_base_hdr *greh;
-       int mac_len = skb->mac_len;
-       __be16 protocol = skb->protocol;
-       int tnl_hlen;
-       bool csum;
-
-       if (unlikely(skb_shinfo(skb)->gso_type &
-                               ~(SKB_GSO_TCPV4 |
-                                 SKB_GSO_TCPV6 |
-                                 SKB_GSO_UDP |
-                                 SKB_GSO_DODGY |
-                                 SKB_GSO_TCP_ECN |
-                                 SKB_GSO_GRE)))
-               goto out;
-
-       if (unlikely(!pskb_may_pull(skb, sizeof(*greh))))
-               goto out;
-
-       greh = (struct gre_base_hdr *)skb_transport_header(skb);
-
-       if (greh->flags & GRE_KEY)
-               ghl += GRE_HEADER_SECTION;
-       if (greh->flags & GRE_SEQ)
-               ghl += GRE_HEADER_SECTION;
-       if (greh->flags & GRE_CSUM) {
-               ghl += GRE_HEADER_SECTION;
-               csum = true;
-       } else
-               csum = false;
-
-       /* setup inner skb. */
-       skb->protocol = greh->protocol;
-       skb->encapsulation = 0;
-
-       if (unlikely(!pskb_may_pull(skb, ghl)))
-               goto out;
-       __skb_pull(skb, ghl);
-       skb_reset_mac_header(skb);
-       skb_set_network_header(skb, skb_inner_network_offset(skb));
-       skb->mac_len = skb_inner_network_offset(skb);
-
-       /* segment inner packet. */
-       enc_features = skb->dev->hw_enc_features & netif_skb_features(skb);
-       segs = skb_mac_gso_segment(skb, enc_features);
-       if (!segs || IS_ERR(segs))
-               goto out;
-
-       skb = segs;
-       tnl_hlen = skb_tnl_header_len(skb);
-       do {
-               __skb_push(skb, ghl);
-               if (csum) {
-                       __be32 *pcsum;
-
-                       if (skb_has_shared_frag(skb)) {
-                               int err;
-
-                               err = __skb_linearize(skb);
-                               if (err) {
-                                       kfree_skb(segs);
-                                       segs = ERR_PTR(err);
-                                       goto out;
-                               }
-                       }
-
-                       greh = (struct gre_base_hdr *)(skb->data);
-                       pcsum = (__be32 *)(greh + 1);
-                       *pcsum = 0;
-                       *(__sum16 *)pcsum = csum_fold(skb_checksum(skb, 0, skb->len, 0));
-               }
-               __skb_push(skb, tnl_hlen - ghl);
-
-               skb_reset_mac_header(skb);
-               skb_set_network_header(skb, mac_len);
-               skb->mac_len = mac_len;
-               skb->protocol = protocol;
-       } while ((skb = skb->next));
-out:
-       return segs;
-}
-
-static int gre_gso_send_check(struct sk_buff *skb)
-{
-       if (!skb->encapsulation)
-               return -EINVAL;
-       return 0;
-}
-
 static const struct net_protocol net_gre_protocol = {
        .handler     = gre_rcv,
        .err_handler = gre_err,
        .netns_ok    = 1,
 };
 
-static const struct net_offload gre_offload = {
-       .callbacks = {
-               .gso_send_check =       gre_gso_send_check,
-               .gso_segment    =       gre_gso_segment,
-       },
-};
-
 static const struct gre_protocol ipgre_protocol = {
        .handler     = gre_cisco_rcv,
        .err_handler = gre_cisco_err,
@@ -485,7 +384,7 @@ static int __init gre_init(void)
                goto err_gre;
        }
 
-       if (inet_add_offload(&gre_offload, IPPROTO_GRE)) {
+       if (gre_offload_init()) {
                pr_err("can't add protocol offload\n");
                goto err_gso;
        }
@@ -501,7 +400,8 @@ err:
 
 static void __exit gre_exit(void)
 {
-       inet_del_offload(&gre_offload, IPPROTO_GRE);
+       gre_offload_exit();
+
        gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO);
        inet_del_protocol(&net_gre_protocol, IPPROTO_GRE);
 }

diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c
new file mode 100644 (file)
index 0000000..a9d8cd2
--- /dev/null
+++ b/net/ipv4/gre_offload.c
@@ -0,0 +1,127 @@
+/*
+ *     IPV4 GSO/GRO offload support
+ *     Linux INET implementation
+ *
+ *     This program is free software; you can redistribute it and/or
+ *     modify it under the terms of the GNU General Public License
+ *     as published by the Free Software Foundation; either version
+ *     2 of the License, or (at your option) any later version.
+ *
+ *     GRE GSO support
+ */
+
+#include <linux/skbuff.h>
+#include <net/protocol.h>
+#include <net/gre.h>
+
+static int gre_gso_send_check(struct sk_buff *skb)
+{
+       if (!skb->encapsulation)
+               return -EINVAL;
+       return 0;
+}
+
+static struct sk_buff *gre_gso_segment(struct sk_buff *skb,
+                                      netdev_features_t features)
+{
+       struct sk_buff *segs = ERR_PTR(-EINVAL);
+       netdev_features_t enc_features;
+       int ghl = GRE_HEADER_SECTION;
+       struct gre_base_hdr *greh;
+       int mac_len = skb->mac_len;
+       __be16 protocol = skb->protocol;
+       int tnl_hlen;
+       bool csum;
+
+       if (unlikely(skb_shinfo(skb)->gso_type &
+                               ~(SKB_GSO_TCPV4 |
+                                 SKB_GSO_TCPV6 |
+                                 SKB_GSO_UDP |
+                                 SKB_GSO_DODGY |
+                                 SKB_GSO_TCP_ECN |
+                                 SKB_GSO_GRE)))
+               goto out;
+
+       if (unlikely(!pskb_may_pull(skb, sizeof(*greh))))
+               goto out;
+
+       greh = (struct gre_base_hdr *)skb_transport_header(skb);
+
+       if (greh->flags & GRE_KEY)
+               ghl += GRE_HEADER_SECTION;
+       if (greh->flags & GRE_SEQ)
+               ghl += GRE_HEADER_SECTION;
+       if (greh->flags & GRE_CSUM) {
+               ghl += GRE_HEADER_SECTION;
+               csum = true;
+       } else
+               csum = false;
+
+       /* setup inner skb. */
+       skb->protocol = greh->protocol;
+       skb->encapsulation = 0;
+
+       if (unlikely(!pskb_may_pull(skb, ghl)))
+               goto out;
+
+       __skb_pull(skb, ghl);
+       skb_reset_mac_header(skb);
+       skb_set_network_header(skb, skb_inner_network_offset(skb));
+       skb->mac_len = skb_inner_network_offset(skb);
+
+       /* segment inner packet. */
+       enc_features = skb->dev->hw_enc_features & netif_skb_features(skb);
+       segs = skb_mac_gso_segment(skb, enc_features);
+       if (!segs || IS_ERR(segs))
+               goto out;
+
+       skb = segs;
+       tnl_hlen = skb_tnl_header_len(skb);
+       do {
+               __skb_push(skb, ghl);
+               if (csum) {
+                       __be32 *pcsum;
+
+                       if (skb_has_shared_frag(skb)) {
+                               int err;
+
+                               err = __skb_linearize(skb);
+                               if (err) {
+                                       kfree_skb(segs);
+                                       segs = ERR_PTR(err);
+                                       goto out;
+                               }
+                       }
+
+                       greh = (struct gre_base_hdr *)(skb->data);
+                       pcsum = (__be32 *)(greh + 1);
+                       *pcsum = 0;
+                       *(__sum16 *)pcsum = csum_fold(skb_checksum(skb, 0, skb->len, 0));
+               }
+               __skb_push(skb, tnl_hlen - ghl);
+
+               skb_reset_mac_header(skb);
+               skb_set_network_header(skb, mac_len);
+               skb->mac_len = mac_len;
+               skb->protocol = protocol;
+       } while ((skb = skb->next));
+out:
+       return segs;
+}
+
+static const struct net_offload gre_offload = {
+       .callbacks = {
+               .gso_send_check = gre_gso_send_check,
+               .gso_segment = gre_gso_segment,
+       },
+};
+
+int __init gre_offload_init(void)
+{
+       return inet_add_offload(&gre_offload, IPPROTO_GRE);
+}
+
+void __exit gre_offload_exit(void)
+{
+       inet_del_offload(&gre_offload, IPPROTO_GRE);
+}