Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 1 | /* |
| 2 | * MPLS GSO Support |
| 3 | * |
| 4 | * Authors: Simon Horman (horms@verge.net.au) |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * Based on: GSO portions of net/ipv4/gre.c |
| 12 | */ |
| 13 | |
| 14 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 15 | |
| 16 | #include <linux/err.h> |
| 17 | #include <linux/module.h> |
| 18 | #include <linux/netdev_features.h> |
| 19 | #include <linux/netdevice.h> |
| 20 | #include <linux/skbuff.h> |
| 21 | |
| 22 | static struct sk_buff *mpls_gso_segment(struct sk_buff *skb, |
| 23 | netdev_features_t features) |
| 24 | { |
| 25 | struct sk_buff *segs = ERR_PTR(-EINVAL); |
| 26 | netdev_features_t mpls_features; |
| 27 | __be16 mpls_protocol; |
| 28 | |
| 29 | if (unlikely(skb_shinfo(skb)->gso_type & |
| 30 | ~(SKB_GSO_TCPV4 | |
| 31 | SKB_GSO_TCPV6 | |
| 32 | SKB_GSO_UDP | |
| 33 | SKB_GSO_DODGY | |
Pravin B Shelar | 4cc1bec | 2014-12-23 16:20:16 -0800 | [diff] [blame^] | 34 | SKB_GSO_TCP_ECN))) |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 35 | goto out; |
| 36 | |
| 37 | /* Setup inner SKB. */ |
| 38 | mpls_protocol = skb->protocol; |
| 39 | skb->protocol = skb->inner_protocol; |
| 40 | |
| 41 | /* Push back the mac header that skb_mac_gso_segment() has pulled. |
| 42 | * It will be re-pulled by the call to skb_mac_gso_segment() below |
| 43 | */ |
| 44 | __skb_push(skb, skb->mac_len); |
| 45 | |
| 46 | /* Segment inner packet. */ |
Florian Westphal | 1e16aa3 | 2014-10-20 13:49:16 +0200 | [diff] [blame] | 47 | mpls_features = skb->dev->mpls_features & features; |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 48 | segs = skb_mac_gso_segment(skb, mpls_features); |
| 49 | |
| 50 | |
| 51 | /* Restore outer protocol. */ |
| 52 | skb->protocol = mpls_protocol; |
| 53 | |
| 54 | /* Re-pull the mac header that the call to skb_mac_gso_segment() |
| 55 | * above pulled. It will be re-pushed after returning |
| 56 | * skb_mac_gso_segment(), an indirect caller of this function. |
| 57 | */ |
Pravin B Shelar | f7065f4 | 2014-10-30 00:49:57 -0700 | [diff] [blame] | 58 | __skb_pull(skb, skb->data - skb_mac_header(skb)); |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 59 | out: |
| 60 | return segs; |
| 61 | } |
| 62 | |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 63 | static struct packet_offload mpls_mc_offload = { |
| 64 | .type = cpu_to_be16(ETH_P_MPLS_MC), |
| 65 | .callbacks = { |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 66 | .gso_segment = mpls_gso_segment, |
| 67 | }, |
| 68 | }; |
| 69 | |
| 70 | static struct packet_offload mpls_uc_offload = { |
| 71 | .type = cpu_to_be16(ETH_P_MPLS_UC), |
| 72 | .callbacks = { |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 73 | .gso_segment = mpls_gso_segment, |
| 74 | }, |
| 75 | }; |
| 76 | |
| 77 | static int __init mpls_gso_init(void) |
| 78 | { |
| 79 | pr_info("MPLS GSO support\n"); |
| 80 | |
| 81 | dev_add_offload(&mpls_uc_offload); |
| 82 | dev_add_offload(&mpls_mc_offload); |
| 83 | |
| 84 | return 0; |
| 85 | } |
| 86 | |
| 87 | static void __exit mpls_gso_exit(void) |
| 88 | { |
| 89 | dev_remove_offload(&mpls_uc_offload); |
| 90 | dev_remove_offload(&mpls_mc_offload); |
| 91 | } |
| 92 | |
| 93 | module_init(mpls_gso_init); |
| 94 | module_exit(mpls_gso_exit); |
| 95 | |
| 96 | MODULE_DESCRIPTION("MPLS GSO support"); |
| 97 | MODULE_AUTHOR("Simon Horman (horms@verge.net.au)"); |
| 98 | MODULE_LICENSE("GPL"); |