[linux-2.6-block.git] / net / mpls / mpls_gso.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *	MPLS GSO Support
 *
 *	Authors: Simon Horman (horms@verge.net.au)
 *
 *	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);
	u16 mac_offset = skb->mac_header;
	netdev_features_t mpls_features;
	u16 mac_len = skb->mac_len;
	__be16 mpls_protocol;
	unsigned int mpls_hlen;

	skb_reset_network_header(skb);
	mpls_hlen = skb_inner_network_header(skb) - skb_network_header(skb);
	if (unlikely(!pskb_may_pull(skb, mpls_hlen)))
		goto out;

	/* Setup inner SKB. */
	mpls_protocol = skb->protocol;
	skb->protocol = skb->inner_protocol;

	__skb_pull(skb, mpls_hlen);

	skb->mac_len = 0;
	skb_reset_mac_header(skb);

	/* Segment inner packet. */
	mpls_features = skb->dev->mpls_features & features;
	segs = skb_mac_gso_segment(skb, mpls_features);
	if (IS_ERR_OR_NULL(segs)) {
		skb_gso_error_unwind(skb, mpls_protocol, mpls_hlen, mac_offset,
				     mac_len);
		goto out;
	}
	skb = segs;

	mpls_hlen += mac_len;
	do {
		skb->mac_len = mac_len;
		skb->protocol = mpls_protocol;

		skb_reset_inner_network_header(skb);

		__skb_push(skb, mpls_hlen);

		skb_reset_mac_header(skb);
		skb_set_network_header(skb, mac_len);
	} while ((skb = skb->next));

out:
	return segs;
}

static struct packet_offload mpls_mc_offload __read_mostly = {
	.type = cpu_to_be16(ETH_P_MPLS_MC),
	.priority = 15,
	.callbacks = {
		.gso_segment    =	mpls_gso_segment,
	},
};

static struct packet_offload mpls_uc_offload __read_mostly = {
	.type = cpu_to_be16(ETH_P_MPLS_UC),
	.priority = 15,
	.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");
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
0d89d203 SH	2	/*
	3	* MPLS GSO Support
	4	*
	5	* Authors: Simon Horman (horms@verge.net.au)
	6	*
0d89d203 SH	7	* Based on: GSO portions of net/ipv4/gre.c
	8	*/
	9
	10	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	11
	12	#include <linux/err.h>
	13	#include <linux/module.h>
	14	#include <linux/netdev_features.h>
	15	#include <linux/netdevice.h>
	16	#include <linux/skbuff.h>
	17
	18	static struct sk_buff mpls_gso_segment(struct sk_buff skb,
	19	netdev_features_t features)
	20	{
	21	struct sk_buff *segs = ERR_PTR(-EINVAL);
48d2ab60	22	u16 mac_offset = skb->mac_header;
0d89d203	23	netdev_features_t mpls_features;
48d2ab60	24	u16 mac_len = skb->mac_len;
0d89d203	25	__be16 mpls_protocol;
48d2ab60 DA	26	unsigned int mpls_hlen;
	27
	28	skb_reset_network_header(skb);
	29	mpls_hlen = skb_inner_network_header(skb) - skb_network_header(skb);
	30	if (unlikely(!pskb_may_pull(skb, mpls_hlen)))
	31	goto out;
0d89d203	32
0d89d203 SH	33	/* Setup inner SKB. */
	34	mpls_protocol = skb->protocol;
	35	skb->protocol = skb->inner_protocol;
	36
48d2ab60 DA	37	__skb_pull(skb, mpls_hlen);
	38
	39	skb->mac_len = 0;
	40	skb_reset_mac_header(skb);
0d89d203 SH	41
0d89d203 SH	42	/* Segment inner packet. */
1e16aa3d	43	mpls_features = skb->dev->mpls_features & features;
0d89d203	44	segs = skb_mac_gso_segment(skb, mpls_features);
48d2ab60 DA	45	if (IS_ERR_OR_NULL(segs)) {
	46	skb_gso_error_unwind(skb, mpls_protocol, mpls_hlen, mac_offset,
	47	mac_len);
	48	goto out;
	49	}
	50	skb = segs;
	51
	52	mpls_hlen += mac_len;
	53	do {
	54	skb->mac_len = mac_len;
	55	skb->protocol = mpls_protocol;
0d89d203	56
48d2ab60	57	skb_reset_inner_network_header(skb);
0d89d203	58
48d2ab60	59	__skb_push(skb, mpls_hlen);
0d89d203	60
48d2ab60 DA	61	skb_reset_mac_header(skb);
	62	skb_set_network_header(skb, mac_len);
	63	} while ((skb = skb->next));
5c7cdf33	64
48d2ab60	65	out:
0d89d203 SH	66	return segs;
	67	}
	68
207895fd	69	static struct packet_offload mpls_mc_offload __read_mostly = {
0d89d203	70	.type = cpu_to_be16(ETH_P_MPLS_MC),
bdef7de4	71	.priority = 15,
0d89d203	72	.callbacks = {
0d89d203 SH	73	.gso_segment = mpls_gso_segment,
	74	},
	75	};
	76
207895fd	77	static struct packet_offload mpls_uc_offload __read_mostly = {
0d89d203	78	.type = cpu_to_be16(ETH_P_MPLS_UC),
bdef7de4	79	.priority = 15,
0d89d203	80	.callbacks = {
0d89d203 SH	81	.gso_segment = mpls_gso_segment,
	82	},
	83	};
	84
	85	static int __init mpls_gso_init(void)
	86	{
	87	pr_info("MPLS GSO support\n");
	88
	89	dev_add_offload(&mpls_uc_offload);
	90	dev_add_offload(&mpls_mc_offload);
	91
	92	return 0;
	93	}
	94
	95	static void __exit mpls_gso_exit(void)
	96	{
	97	dev_remove_offload(&mpls_uc_offload);
	98	dev_remove_offload(&mpls_mc_offload);
	99	}
	100
	101	module_init(mpls_gso_init);
	102	module_exit(mpls_gso_exit);
	103
	104	MODULE_DESCRIPTION("MPLS GSO support");
	105	MODULE_AUTHOR("Simon Horman (horms@verge.net.au)");
	106	MODULE_LICENSE("GPL");