114 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			114 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *	MPLS GSO Support
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|  *
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|  *	Authors: Simon Horman (horms@verge.net.au)
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|  *
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|  *	This program is free software; you can redistribute it and/or
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|  *	modify it under the terms of the GNU General Public License
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|  *	as published by the Free Software Foundation; either version
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|  *	2 of the License, or (at your option) any later version.
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|  *
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|  *	Based on: GSO portions of net/ipv4/gre.c
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|  */
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| 
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| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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| 
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| #include <linux/err.h>
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| #include <linux/module.h>
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| #include <linux/netdev_features.h>
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| #include <linux/netdevice.h>
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| #include <linux/skbuff.h>
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| #include <net/mpls.h>
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| 
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| static struct sk_buff *mpls_gso_segment(struct sk_buff *skb,
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| 				       netdev_features_t features)
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| {
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| 	struct sk_buff *segs = ERR_PTR(-EINVAL);
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| 	u16 mac_offset = skb->mac_header;
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| 	netdev_features_t mpls_features;
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| 	u16 mac_len = skb->mac_len;
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| 	__be16 mpls_protocol;
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| 	unsigned int mpls_hlen;
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| 
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| 	skb_reset_network_header(skb);
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| 	mpls_hlen = skb_inner_network_header(skb) - skb_network_header(skb);
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| 	if (unlikely(!mpls_hlen || mpls_hlen % MPLS_HLEN))
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| 		goto out;
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| 	if (unlikely(!pskb_may_pull(skb, mpls_hlen)))
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| 		goto out;
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| 
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| 	/* Setup inner SKB. */
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| 	mpls_protocol = skb->protocol;
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| 	skb->protocol = skb->inner_protocol;
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| 
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| 	__skb_pull(skb, mpls_hlen);
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| 
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| 	skb->mac_len = 0;
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| 	skb_reset_mac_header(skb);
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| 
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| 	/* Segment inner packet. */
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| 	mpls_features = skb->dev->mpls_features & features;
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| 	segs = skb_mac_gso_segment(skb, mpls_features);
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| 	if (IS_ERR_OR_NULL(segs)) {
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| 		skb_gso_error_unwind(skb, mpls_protocol, mpls_hlen, mac_offset,
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| 				     mac_len);
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| 		goto out;
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| 	}
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| 	skb = segs;
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| 
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| 	mpls_hlen += mac_len;
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| 	do {
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| 		skb->mac_len = mac_len;
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| 		skb->protocol = mpls_protocol;
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| 
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| 		skb_reset_inner_network_header(skb);
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| 
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| 		__skb_push(skb, mpls_hlen);
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| 
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| 		skb_reset_mac_header(skb);
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| 		skb_set_network_header(skb, mac_len);
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| 	} while ((skb = skb->next));
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| 
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| out:
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| 	return segs;
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| }
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| 
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| static struct packet_offload mpls_mc_offload __read_mostly = {
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| 	.type = cpu_to_be16(ETH_P_MPLS_MC),
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| 	.priority = 15,
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| 	.callbacks = {
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| 		.gso_segment    =	mpls_gso_segment,
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| 	},
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| };
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| 
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| static struct packet_offload mpls_uc_offload __read_mostly = {
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| 	.type = cpu_to_be16(ETH_P_MPLS_UC),
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| 	.priority = 15,
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| 	.callbacks = {
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| 		.gso_segment    =	mpls_gso_segment,
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| 	},
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| };
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| 
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| static int __init mpls_gso_init(void)
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| {
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| 	pr_info("MPLS GSO support\n");
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| 
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| 	dev_add_offload(&mpls_uc_offload);
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| 	dev_add_offload(&mpls_mc_offload);
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| 
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| 	return 0;
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| }
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| 
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| static void __exit mpls_gso_exit(void)
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| {
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| 	dev_remove_offload(&mpls_uc_offload);
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| 	dev_remove_offload(&mpls_mc_offload);
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| }
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| 
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| module_init(mpls_gso_init);
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| module_exit(mpls_gso_exit);
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| 
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| MODULE_DESCRIPTION("MPLS GSO support");
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| MODULE_AUTHOR("Simon Horman (horms@verge.net.au)");
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| MODULE_LICENSE("GPL");
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