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); |
David Ahern | 48d2ab6 | 2016-08-24 20:10:44 -0700 | [diff] [blame] | 26 | u16 mac_offset = skb->mac_header; |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 27 | netdev_features_t mpls_features; |
David Ahern | 48d2ab6 | 2016-08-24 20:10:44 -0700 | [diff] [blame] | 28 | u16 mac_len = skb->mac_len; |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 29 | __be16 mpls_protocol; |
David Ahern | 48d2ab6 | 2016-08-24 20:10:44 -0700 | [diff] [blame] | 30 | unsigned int mpls_hlen; |
| 31 | |
| 32 | skb_reset_network_header(skb); |
| 33 | mpls_hlen = skb_inner_network_header(skb) - skb_network_header(skb); |
| 34 | if (unlikely(!pskb_may_pull(skb, mpls_hlen))) |
| 35 | goto out; |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 36 | |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 37 | /* Setup inner SKB. */ |
| 38 | mpls_protocol = skb->protocol; |
| 39 | skb->protocol = skb->inner_protocol; |
| 40 | |
David Ahern | 48d2ab6 | 2016-08-24 20:10:44 -0700 | [diff] [blame] | 41 | __skb_pull(skb, mpls_hlen); |
| 42 | |
| 43 | skb->mac_len = 0; |
| 44 | skb_reset_mac_header(skb); |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 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); |
David Ahern | 48d2ab6 | 2016-08-24 20:10:44 -0700 | [diff] [blame] | 49 | if (IS_ERR_OR_NULL(segs)) { |
| 50 | skb_gso_error_unwind(skb, mpls_protocol, mpls_hlen, mac_offset, |
| 51 | mac_len); |
| 52 | goto out; |
| 53 | } |
| 54 | skb = segs; |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 55 | |
David Ahern | 48d2ab6 | 2016-08-24 20:10:44 -0700 | [diff] [blame] | 56 | mpls_hlen += mac_len; |
| 57 | do { |
| 58 | skb->mac_len = mac_len; |
| 59 | skb->protocol = mpls_protocol; |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 60 | |
David Ahern | 48d2ab6 | 2016-08-24 20:10:44 -0700 | [diff] [blame] | 61 | skb_reset_inner_network_header(skb); |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 62 | |
David Ahern | 48d2ab6 | 2016-08-24 20:10:44 -0700 | [diff] [blame] | 63 | __skb_push(skb, mpls_hlen); |
Tom Herbert | 5c7cdf33 | 2016-05-18 09:06:09 -0700 | [diff] [blame] | 64 | |
David Ahern | 48d2ab6 | 2016-08-24 20:10:44 -0700 | [diff] [blame] | 65 | skb_reset_mac_header(skb); |
| 66 | skb_set_network_header(skb, mac_len); |
| 67 | } while ((skb = skb->next)); |
| 68 | |
| 69 | out: |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 70 | return segs; |
| 71 | } |
| 72 | |
Daniel Borkmann | 207895fd3 | 2015-01-29 12:15:03 +0100 | [diff] [blame] | 73 | static struct packet_offload mpls_mc_offload __read_mostly = { |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 74 | .type = cpu_to_be16(ETH_P_MPLS_MC), |
David S. Miller | bdef7de | 2015-06-01 14:56:09 -0700 | [diff] [blame] | 75 | .priority = 15, |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 76 | .callbacks = { |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 77 | .gso_segment = mpls_gso_segment, |
| 78 | }, |
| 79 | }; |
| 80 | |
Daniel Borkmann | 207895fd3 | 2015-01-29 12:15:03 +0100 | [diff] [blame] | 81 | static struct packet_offload mpls_uc_offload __read_mostly = { |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 82 | .type = cpu_to_be16(ETH_P_MPLS_UC), |
David S. Miller | bdef7de | 2015-06-01 14:56:09 -0700 | [diff] [blame] | 83 | .priority = 15, |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 84 | .callbacks = { |
Simon Horman | 0d89d20 | 2013-05-23 21:02:52 +0000 | [diff] [blame] | 85 | .gso_segment = mpls_gso_segment, |
| 86 | }, |
| 87 | }; |
| 88 | |
| 89 | static int __init mpls_gso_init(void) |
| 90 | { |
| 91 | pr_info("MPLS GSO support\n"); |
| 92 | |
| 93 | dev_add_offload(&mpls_uc_offload); |
| 94 | dev_add_offload(&mpls_mc_offload); |
| 95 | |
| 96 | return 0; |
| 97 | } |
| 98 | |
| 99 | static void __exit mpls_gso_exit(void) |
| 100 | { |
| 101 | dev_remove_offload(&mpls_uc_offload); |
| 102 | dev_remove_offload(&mpls_mc_offload); |
| 103 | } |
| 104 | |
| 105 | module_init(mpls_gso_init); |
| 106 | module_exit(mpls_gso_exit); |
| 107 | |
| 108 | MODULE_DESCRIPTION("MPLS GSO support"); |
| 109 | MODULE_AUTHOR("Simon Horman (horms@verge.net.au)"); |
| 110 | MODULE_LICENSE("GPL"); |