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Diffstat (limited to 'net/mpls/mpls_gso.c')
-rw-r--r--net/mpls/mpls_gso.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/net/mpls/mpls_gso.c b/net/mpls/mpls_gso.c
new file mode 100644
index 000000000..809df534a
--- /dev/null
+++ b/net/mpls/mpls_gso.c
@@ -0,0 +1,98 @@
+/*
+ * MPLS GSO Support
+ *
+ * Authors: Simon Horman (horms@verge.net.au)
+ *
+ * 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.
+ *
+ * Based on: GSO portions of net/ipv4/gre.c
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/netdev_features.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+
+static struct sk_buff *mpls_gso_segment(struct sk_buff *skb,
+ netdev_features_t features)
+{
+ struct sk_buff *segs = ERR_PTR(-EINVAL);
+ netdev_features_t mpls_features;
+ __be16 mpls_protocol;
+
+ if (unlikely(skb_shinfo(skb)->gso_type &
+ ~(SKB_GSO_TCPV4 |
+ SKB_GSO_TCPV6 |
+ SKB_GSO_UDP |
+ SKB_GSO_DODGY |
+ SKB_GSO_TCP_ECN)))
+ goto out;
+
+ /* Setup inner SKB. */
+ mpls_protocol = skb->protocol;
+ skb->protocol = skb->inner_protocol;
+
+ /* Push back the mac header that skb_mac_gso_segment() has pulled.
+ * It will be re-pulled by the call to skb_mac_gso_segment() below
+ */
+ __skb_push(skb, skb->mac_len);
+
+ /* Segment inner packet. */
+ mpls_features = skb->dev->mpls_features & features;
+ segs = skb_mac_gso_segment(skb, mpls_features);
+
+
+ /* Restore outer protocol. */
+ skb->protocol = mpls_protocol;
+
+ /* Re-pull the mac header that the call to skb_mac_gso_segment()
+ * above pulled. It will be re-pushed after returning
+ * skb_mac_gso_segment(), an indirect caller of this function.
+ */
+ __skb_pull(skb, skb->data - skb_mac_header(skb));
+out:
+ return segs;
+}
+
+static struct packet_offload mpls_mc_offload __read_mostly = {
+ .type = cpu_to_be16(ETH_P_MPLS_MC),
+ .callbacks = {
+ .gso_segment = mpls_gso_segment,
+ },
+};
+
+static struct packet_offload mpls_uc_offload __read_mostly = {
+ .type = cpu_to_be16(ETH_P_MPLS_UC),
+ .callbacks = {
+ .gso_segment = mpls_gso_segment,
+ },
+};
+
+static int __init mpls_gso_init(void)
+{
+ pr_info("MPLS GSO support\n");
+
+ dev_add_offload(&mpls_uc_offload);
+ dev_add_offload(&mpls_mc_offload);
+
+ return 0;
+}
+
+static void __exit mpls_gso_exit(void)
+{
+ dev_remove_offload(&mpls_uc_offload);
+ dev_remove_offload(&mpls_mc_offload);
+}
+
+module_init(mpls_gso_init);
+module_exit(mpls_gso_exit);
+
+MODULE_DESCRIPTION("MPLS GSO support");
+MODULE_AUTHOR("Simon Horman (horms@verge.net.au)");
+MODULE_LICENSE("GPL");