[mirror_ubuntu-hirsute-kernel.git] / net / ipv6 / ip6_offload.c

/*
 *	IPV6 GSO/GRO offload support
 *	Linux INET6 implementation
 *
 *	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.
 */

#include <linux/kernel.h>
#include <linux/socket.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/printk.h>

#include <net/protocol.h>
#include <net/ipv6.h>

#include "ip6_offload.h"

static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
{
	const struct net_offload *ops = NULL;

	for (;;) {
		struct ipv6_opt_hdr *opth;
		int len;

		if (proto != NEXTHDR_HOP) {
			ops = rcu_dereference(inet6_offloads[proto]);

			if (unlikely(!ops))
				break;

			if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
				break;
		}

		if (unlikely(!pskb_may_pull(skb, 8)))
			break;

		opth = (void *)skb->data;
		len = ipv6_optlen(opth);

		if (unlikely(!pskb_may_pull(skb, len)))
			break;

		opth = (void *)skb->data;
		proto = opth->nexthdr;
		__skb_pull(skb, len);
	}

	return proto;
}

static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb,
	netdev_features_t features)
{
	struct sk_buff *segs = ERR_PTR(-EINVAL);
	struct ipv6hdr *ipv6h;
	const struct net_offload *ops;
	int proto;
	struct frag_hdr *fptr;
	unsigned int unfrag_ip6hlen;
	unsigned int payload_len;
	u8 *prevhdr;
	int offset = 0;
	bool encap, udpfrag;
	int nhoff;

	if (unlikely(skb_shinfo(skb)->gso_type &
		     ~(SKB_GSO_TCPV4 |
		       SKB_GSO_UDP |
		       SKB_GSO_DODGY |
		       SKB_GSO_TCP_ECN |
		       SKB_GSO_TCP_FIXEDID |
		       SKB_GSO_TCPV6 |
		       SKB_GSO_GRE |
		       SKB_GSO_GRE_CSUM |
		       SKB_GSO_IPIP |
		       SKB_GSO_SIT |
		       SKB_GSO_UDP_TUNNEL |
		       SKB_GSO_UDP_TUNNEL_CSUM |
		       SKB_GSO_TUNNEL_REMCSUM |
		       SKB_GSO_PARTIAL |
		       0)))
		goto out;

	skb_reset_network_header(skb);
	nhoff = skb_network_header(skb) - skb_mac_header(skb);
	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
		goto out;

	encap = SKB_GSO_CB(skb)->encap_level > 0;
	if (encap)
		features &= skb->dev->hw_enc_features;
	SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);

	ipv6h = ipv6_hdr(skb);
	__skb_pull(skb, sizeof(*ipv6h));
	segs = ERR_PTR(-EPROTONOSUPPORT);

	proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);

	if (skb->encapsulation &&
	    skb_shinfo(skb)->gso_type & (SKB_GSO_SIT|SKB_GSO_IPIP))
		udpfrag = proto == IPPROTO_UDP && encap;
	else
		udpfrag = proto == IPPROTO_UDP && !skb->encapsulation;

	ops = rcu_dereference(inet6_offloads[proto]);
	if (likely(ops && ops->callbacks.gso_segment)) {
		skb_reset_transport_header(skb);
		segs = ops->callbacks.gso_segment(skb, features);
	}

	if (IS_ERR(segs))
		goto out;

	for (skb = segs; skb; skb = skb->next) {
		ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
		if (skb_is_gso(skb))
			payload_len = skb_shinfo(skb)->gso_size +
				      SKB_GSO_CB(skb)->data_offset +
				      skb->head - (unsigned char *)(ipv6h + 1);
		else
			payload_len = skb->len - nhoff - sizeof(*ipv6h);
		ipv6h->payload_len = htons(payload_len);
		skb->network_header = (u8 *)ipv6h - skb->head;

		if (udpfrag) {
			unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
			fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen);
			fptr->frag_off = htons(offset);
			if (skb->next)
				fptr->frag_off |= htons(IP6_MF);
			offset += (ntohs(ipv6h->payload_len) -
				   sizeof(struct frag_hdr));
		}
		if (encap)
			skb_reset_inner_headers(skb);
	}

out:
	return segs;
}

/* Return the total length of all the extension hdrs, following the same
 * logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs.
 */
static int ipv6_exthdrs_len(struct ipv6hdr *iph,
			    const struct net_offload **opps)
{
	struct ipv6_opt_hdr *opth = (void *)iph;
	int len = 0, proto, optlen = sizeof(*iph);

	proto = iph->nexthdr;
	for (;;) {
		if (proto != NEXTHDR_HOP) {
			*opps = rcu_dereference(inet6_offloads[proto]);
			if (unlikely(!(*opps)))
				break;
			if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR))
				break;
		}
		opth = (void *)opth + optlen;
		optlen = ipv6_optlen(opth);
		len += optlen;
		proto = opth->nexthdr;
	}
	return len;
}

static struct sk_buff **ipv6_gro_receive(struct sk_buff **head,
					 struct sk_buff *skb)
{
	const struct net_offload *ops;
	struct sk_buff **pp = NULL;
	struct sk_buff *p;
	struct ipv6hdr *iph;
	unsigned int nlen;
	unsigned int hlen;
	unsigned int off;
	u16 flush = 1;
	int proto;

	off = skb_gro_offset(skb);
	hlen = off + sizeof(*iph);
	iph = skb_gro_header_fast(skb, off);
	if (skb_gro_header_hard(skb, hlen)) {
		iph = skb_gro_header_slow(skb, hlen, off);
		if (unlikely(!iph))
			goto out;
	}

	skb_set_network_header(skb, off);
	skb_gro_pull(skb, sizeof(*iph));
	skb_set_transport_header(skb, skb_gro_offset(skb));

	flush += ntohs(iph->payload_len) != skb_gro_len(skb);

	rcu_read_lock();
	proto = iph->nexthdr;
	ops = rcu_dereference(inet6_offloads[proto]);
	if (!ops || !ops->callbacks.gro_receive) {
		__pskb_pull(skb, skb_gro_offset(skb));
		proto = ipv6_gso_pull_exthdrs(skb, proto);
		skb_gro_pull(skb, -skb_transport_offset(skb));
		skb_reset_transport_header(skb);
		__skb_push(skb, skb_gro_offset(skb));

		ops = rcu_dereference(inet6_offloads[proto]);
		if (!ops || !ops->callbacks.gro_receive)
			goto out_unlock;

		iph = ipv6_hdr(skb);
	}

	NAPI_GRO_CB(skb)->proto = proto;

	flush--;
	nlen = skb_network_header_len(skb);

	for (p = *head; p; p = p->next) {
		const struct ipv6hdr *iph2;
		__be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */

		if (!NAPI_GRO_CB(p)->same_flow)
			continue;

		iph2 = (struct ipv6hdr *)(p->data + off);
		first_word = *(__be32 *)iph ^ *(__be32 *)iph2;

		/* All fields must match except length and Traffic Class.
		 * XXX skbs on the gro_list have all been parsed and pulled
		 * already so we don't need to compare nlen
		 * (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops)))
		 * memcmp() alone below is suffcient, right?
		 */
		 if ((first_word & htonl(0xF00FFFFF)) ||
		    memcmp(&iph->nexthdr, &iph2->nexthdr,
			   nlen - offsetof(struct ipv6hdr, nexthdr))) {
			NAPI_GRO_CB(p)->same_flow = 0;
			continue;
		}
		/* flush if Traffic Class fields are different */
		NAPI_GRO_CB(p)->flush |= !!(first_word & htonl(0x0FF00000));
		NAPI_GRO_CB(p)->flush |= flush;

		/* If the previous IP ID value was based on an atomic
		 * datagram we can overwrite the value and ignore it.
		 */
		if (NAPI_GRO_CB(skb)->is_atomic)
			NAPI_GRO_CB(p)->flush_id = 0;
	}

	NAPI_GRO_CB(skb)->is_atomic = true;
	NAPI_GRO_CB(skb)->flush |= flush;

	skb_gro_postpull_rcsum(skb, iph, nlen);

	pp = ops->callbacks.gro_receive(head, skb);

out_unlock:
	rcu_read_unlock();

out:
	NAPI_GRO_CB(skb)->flush |= flush;

	return pp;
}

static struct sk_buff **sit_gro_receive(struct sk_buff **head,
					struct sk_buff *skb)
{
	if (NAPI_GRO_CB(skb)->encap_mark) {
		NAPI_GRO_CB(skb)->flush = 1;
		return NULL;
	}

	NAPI_GRO_CB(skb)->encap_mark = 1;

	return ipv6_gro_receive(head, skb);
}

static int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
{
	const struct net_offload *ops;
	struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + nhoff);
	int err = -ENOSYS;

	if (skb->encapsulation)
		skb_set_inner_network_header(skb, nhoff);

	iph->payload_len = htons(skb->len - nhoff - sizeof(*iph));

	rcu_read_lock();

	nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
	if (WARN_ON(!ops || !ops->callbacks.gro_complete))
		goto out_unlock;

	err = ops->callbacks.gro_complete(skb, nhoff);

out_unlock:
	rcu_read_unlock();

	return err;
}

static int sit_gro_complete(struct sk_buff *skb, int nhoff)
{
	skb->encapsulation = 1;
	skb_shinfo(skb)->gso_type |= SKB_GSO_SIT;
	return ipv6_gro_complete(skb, nhoff);
}

static struct packet_offload ipv6_packet_offload __read_mostly = {
	.type = cpu_to_be16(ETH_P_IPV6),
	.callbacks = {
		.gso_segment = ipv6_gso_segment,
		.gro_receive = ipv6_gro_receive,
		.gro_complete = ipv6_gro_complete,
	},
};

static const struct net_offload sit_offload = {
	.callbacks = {
		.gso_segment	= ipv6_gso_segment,
		.gro_receive    = sit_gro_receive,
		.gro_complete   = sit_gro_complete,
	},
};

static int __init ipv6_offload_init(void)
{

	if (tcpv6_offload_init() < 0)
		pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
	if (ipv6_exthdrs_offload_init() < 0)
		pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);

	dev_add_offload(&ipv6_packet_offload);

	inet_add_offload(&sit_offload, IPPROTO_IPV6);

	return 0;
}

fs_initcall(ipv6_offload_init);
Commit	Line	Data
d1da932e VY	1	/*
	2	* IPV6 GSO/GRO offload support
	3	* Linux INET6 implementation
	4	*
	5	* This program is free software; you can redistribute it and/or
	6	* modify it under the terms of the GNU General Public License
	7	* as published by the Free Software Foundation; either version
	8	* 2 of the License, or (at your option) any later version.
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/socket.h>
	13	#include <linux/netdevice.h>
	14	#include <linux/skbuff.h>
c6b641a4	15	#include <linux/printk.h>
d1da932e VY	16
	17	#include <net/protocol.h>
	18	#include <net/ipv6.h>
	19
	20	#include "ip6_offload.h"
	21
	22	static int ipv6_gso_pull_exthdrs(struct sk_buff *skb, int proto)
	23	{
	24	const struct net_offload *ops = NULL;
	25
	26	for (;;) {
	27	struct ipv6_opt_hdr *opth;
	28	int len;
	29
	30	if (proto != NEXTHDR_HOP) {
	31	ops = rcu_dereference(inet6_offloads[proto]);
	32
	33	if (unlikely(!ops))
	34	break;
	35
	36	if (!(ops->flags & INET6_PROTO_GSO_EXTHDR))
	37	break;
	38	}
	39
	40	if (unlikely(!pskb_may_pull(skb, 8)))
	41	break;
	42
	43	opth = (void *)skb->data;
	44	len = ipv6_optlen(opth);
	45
	46	if (unlikely(!pskb_may_pull(skb, len)))
	47	break;
	48
fc6fb41c	49	opth = (void *)skb->data;
d1da932e VY	50	proto = opth->nexthdr;
	51	__skb_pull(skb, len);
	52	}
	53
	54	return proto;
	55	}
	56
d1da932e VY	57	static struct sk_buff ipv6_gso_segment(struct sk_buff skb,
	58	netdev_features_t features)
	59	{
	60	struct sk_buff *segs = ERR_PTR(-EINVAL);
	61	struct ipv6hdr *ipv6h;
	62	const struct net_offload *ops;
	63	int proto;
	64	struct frag_hdr *fptr;
	65	unsigned int unfrag_ip6hlen;
802ab55a	66	unsigned int payload_len;
d1da932e VY	67	u8 *prevhdr;
d1da932e VY	68	int offset = 0;
91a48a2e	69	bool encap, udpfrag;
d3e5e006	70	int nhoff;
d1da932e	71
d1da932e	72	if (unlikely(skb_shinfo(skb)->gso_type &
b6fef4c6 AD	73	~(SKB_GSO_TCPV4 \|
b6fef4c6 AD	74	SKB_GSO_UDP \|
d1da932e VY	75	SKB_GSO_DODGY \|
d1da932e VY	76	SKB_GSO_TCP_ECN \|
cbc53e08 AD	77	SKB_GSO_TCP_FIXEDID \|
cbc53e08 AD	78	SKB_GSO_TCPV6 \|
68c33163	79	SKB_GSO_GRE \|
4749c09c	80	SKB_GSO_GRE_CSUM \|
cb32f511	81	SKB_GSO_IPIP \|
61c1db7f	82	SKB_GSO_SIT \|
73136267	83	SKB_GSO_UDP_TUNNEL \|
0f4f4ffa	84	SKB_GSO_UDP_TUNNEL_CSUM \|
e585f236	85	SKB_GSO_TUNNEL_REMCSUM \|
802ab55a	86	SKB_GSO_PARTIAL \|
d1da932e VY	87	0)))
	88	goto out;
	89
d3e5e006 ED	90	skb_reset_network_header(skb);
d3e5e006 ED	91	nhoff = skb_network_header(skb) - skb_mac_header(skb);
d1da932e VY	92	if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
	93	goto out;
	94
91a48a2e HFS	95	encap = SKB_GSO_CB(skb)->encap_level > 0;
91a48a2e HFS	96	if (encap)
1e16aa3d	97	features &= skb->dev->hw_enc_features;
d3e5e006 ED	98	SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);
d3e5e006 ED	99
d1da932e VY	100	ipv6h = ipv6_hdr(skb);
	101	__skb_pull(skb, sizeof(*ipv6h));
	102	segs = ERR_PTR(-EPROTONOSUPPORT);
	103
	104	proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
b917eb15	105
91a48a2e HFS	106	if (skb->encapsulation &&
	107	skb_shinfo(skb)->gso_type & (SKB_GSO_SIT\|SKB_GSO_IPIP))
	108	udpfrag = proto == IPPROTO_UDP && encap;
	109	else
	110	udpfrag = proto == IPPROTO_UDP && !skb->encapsulation;
	111
d1da932e	112	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	113	if (likely(ops && ops->callbacks.gso_segment)) {
d1da932e	114	skb_reset_transport_header(skb);
f191a1d1	115	segs = ops->callbacks.gso_segment(skb, features);
d1da932e	116	}
d1da932e VY	117
	118	if (IS_ERR(segs))
	119	goto out;
	120
	121	for (skb = segs; skb; skb = skb->next) {
d3e5e006	122	ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff);
802ab55a AD	123	if (skb_is_gso(skb))
	124	payload_len = skb_shinfo(skb)->gso_size +
	125	SKB_GSO_CB(skb)->data_offset +
	126	skb->head - (unsigned char *)(ipv6h + 1);
	127	else
	128	payload_len = skb->len - nhoff - sizeof(*ipv6h);
	129	ipv6h->payload_len = htons(payload_len);
d3e5e006 ED	130	skb->network_header = (u8 *)ipv6h - skb->head;
d3e5e006 ED	131
91a48a2e	132	if (udpfrag) {
d1da932e	133	unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
d3e5e006	134	fptr = (struct frag_hdr )((u8 )ipv6h + unfrag_ip6hlen);
d1da932e	135	fptr->frag_off = htons(offset);
53b24b8f	136	if (skb->next)
d1da932e VY	137	fptr->frag_off \|= htons(IP6_MF);
	138	offset += (ntohs(ipv6h->payload_len) -
	139	sizeof(struct frag_hdr));
	140	}
91a48a2e HFS	141	if (encap)
91a48a2e HFS	142	skb_reset_inner_headers(skb);
d1da932e VY	143	}
	144
	145	out:
	146	return segs;
	147	}
	148
299603e8 JC	149	/* Return the total length of all the extension hdrs, following the same
	150	* logic in ipv6_gso_pull_exthdrs() when parsing ext-hdrs.
	151	*/
	152	static int ipv6_exthdrs_len(struct ipv6hdr *iph,
	153	const struct net_offload **opps)
	154	{
810c23a3 JC	155	struct ipv6_opt_hdr opth = (void )iph;
810c23a3 JC	156	int len = 0, proto, optlen = sizeof(*iph);
299603e8 JC	157
	158	proto = iph->nexthdr;
	159	for (;;) {
	160	if (proto != NEXTHDR_HOP) {
	161	*opps = rcu_dereference(inet6_offloads[proto]);
	162	if (unlikely(!(*opps)))
	163	break;
	164	if (!((*opps)->flags & INET6_PROTO_GSO_EXTHDR))
	165	break;
	166	}
810c23a3 JC	167	opth = (void *)opth + optlen;
810c23a3 JC	168	optlen = ipv6_optlen(opth);
299603e8 JC	169	len += optlen;
	170	proto = opth->nexthdr;
	171	}
	172	return len;
	173	}
	174
d1da932e VY	175	static struct sk_buff ipv6_gro_receive(struct sk_buff head,
	176	struct sk_buff *skb)
	177	{
	178	const struct net_offload *ops;
	179	struct sk_buff **pp = NULL;
	180	struct sk_buff *p;
	181	struct ipv6hdr *iph;
	182	unsigned int nlen;
	183	unsigned int hlen;
	184	unsigned int off;
bf5a755f	185	u16 flush = 1;
d1da932e	186	int proto;
d1da932e VY	187
	188	off = skb_gro_offset(skb);
	189	hlen = off + sizeof(*iph);
	190	iph = skb_gro_header_fast(skb, off);
	191	if (skb_gro_header_hard(skb, hlen)) {
	192	iph = skb_gro_header_slow(skb, hlen, off);
	193	if (unlikely(!iph))
	194	goto out;
	195	}
	196
299603e8	197	skb_set_network_header(skb, off);
d1da932e VY	198	skb_gro_pull(skb, sizeof(*iph));
	199	skb_set_transport_header(skb, skb_gro_offset(skb));
	200
	201	flush += ntohs(iph->payload_len) != skb_gro_len(skb);
	202
	203	rcu_read_lock();
	204	proto = iph->nexthdr;
	205	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	206	if (!ops \|\| !ops->callbacks.gro_receive) {
d1da932e VY	207	__pskb_pull(skb, skb_gro_offset(skb));
	208	proto = ipv6_gso_pull_exthdrs(skb, proto);
	209	skb_gro_pull(skb, -skb_transport_offset(skb));
	210	skb_reset_transport_header(skb);
	211	__skb_push(skb, skb_gro_offset(skb));
	212
	213	ops = rcu_dereference(inet6_offloads[proto]);
f191a1d1	214	if (!ops \|\| !ops->callbacks.gro_receive)
d1da932e VY	215	goto out_unlock;
	216
	217	iph = ipv6_hdr(skb);
	218	}
	219
	220	NAPI_GRO_CB(skb)->proto = proto;
	221
	222	flush--;
	223	nlen = skb_network_header_len(skb);
	224
	225	for (p = *head; p; p = p->next) {
	226	const struct ipv6hdr *iph2;
	227	__be32 first_word; /* <Version:4><Traffic_Class:8><Flow_Label:20> */
	228
	229	if (!NAPI_GRO_CB(p)->same_flow)
	230	continue;
	231
299603e8	232	iph2 = (struct ipv6hdr *)(p->data + off);
67ba4152	233	first_word = (__be32 )iph ^ (__be32 )iph2;
d1da932e	234
299603e8 JC	235	/* All fields must match except length and Traffic Class.
	236	* XXX skbs on the gro_list have all been parsed and pulled
	237	* already so we don't need to compare nlen
	238	* (nlen != (sizeof(*iph2) + ipv6_exthdrs_len(iph2, &ops)))
	239	* memcmp() alone below is suffcient, right?
	240	*/
	241	if ((first_word & htonl(0xF00FFFFF)) \|\|
d1da932e VY	242	memcmp(&iph->nexthdr, &iph2->nexthdr,
	243	nlen - offsetof(struct ipv6hdr, nexthdr))) {
	244	NAPI_GRO_CB(p)->same_flow = 0;
	245	continue;
	246	}
	247	/* flush if Traffic Class fields are different */
	248	NAPI_GRO_CB(p)->flush \|= !!(first_word & htonl(0x0FF00000));
	249	NAPI_GRO_CB(p)->flush \|= flush;
03d56daa	250
1530545e AD	251	/* If the previous IP ID value was based on an atomic
	252	* datagram we can overwrite the value and ignore it.
	253	*/
	254	if (NAPI_GRO_CB(skb)->is_atomic)
	255	NAPI_GRO_CB(p)->flush_id = 0;
d1da932e VY	256	}
d1da932e VY	257
1530545e	258	NAPI_GRO_CB(skb)->is_atomic = true;
d1da932e VY	259	NAPI_GRO_CB(skb)->flush \|= flush;
d1da932e VY	260
4de462ab	261	skb_gro_postpull_rcsum(skb, iph, nlen);
d1da932e	262
f191a1d1	263	pp = ops->callbacks.gro_receive(head, skb);
d1da932e	264
d1da932e VY	265	out_unlock:
	266	rcu_read_unlock();
	267
	268	out:
	269	NAPI_GRO_CB(skb)->flush \|= flush;
	270
	271	return pp;
	272	}
	273
fac8e0f5 JG	274	static struct sk_buff sit_gro_receive(struct sk_buff head,
	275	struct sk_buff *skb)
	276	{
	277	if (NAPI_GRO_CB(skb)->encap_mark) {
	278	NAPI_GRO_CB(skb)->flush = 1;
	279	return NULL;
	280	}
	281
	282	NAPI_GRO_CB(skb)->encap_mark = 1;
	283
	284	return ipv6_gro_receive(head, skb);
	285	}
	286
299603e8	287	static int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
d1da932e VY	288	{
d1da932e VY	289	const struct net_offload *ops;
299603e8	290	struct ipv6hdr iph = (struct ipv6hdr )(skb->data + nhoff);
d1da932e VY	291	int err = -ENOSYS;
d1da932e VY	292
feec0cb3 ED	293	if (skb->encapsulation)
	294	skb_set_inner_network_header(skb, nhoff);
	295
299603e8	296	iph->payload_len = htons(skb->len - nhoff - sizeof(*iph));
d1da932e VY	297
d1da932e VY	298	rcu_read_lock();
299603e8 JC	299
299603e8 JC	300	nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
f191a1d1	301	if (WARN_ON(!ops \|\| !ops->callbacks.gro_complete))
d1da932e VY	302	goto out_unlock;
d1da932e VY	303
299603e8	304	err = ops->callbacks.gro_complete(skb, nhoff);
d1da932e VY	305
	306	out_unlock:
	307	rcu_read_unlock();
	308
	309	return err;
	310	}
	311
feec0cb3 ED	312	static int sit_gro_complete(struct sk_buff *skb, int nhoff)
	313	{
	314	skb->encapsulation = 1;
	315	skb_shinfo(skb)->gso_type \|= SKB_GSO_SIT;
	316	return ipv6_gro_complete(skb, nhoff);
	317	}
	318
d1da932e VY	319	static struct packet_offload ipv6_packet_offload __read_mostly = {
d1da932e VY	320	.type = cpu_to_be16(ETH_P_IPV6),
f191a1d1	321	.callbacks = {
f191a1d1 VY	322	.gso_segment = ipv6_gso_segment,
	323	.gro_receive = ipv6_gro_receive,
	324	.gro_complete = ipv6_gro_complete,
	325	},
d1da932e VY	326	};
d1da932e VY	327
61c1db7f ED	328	static const struct net_offload sit_offload = {
61c1db7f ED	329	.callbacks = {
61c1db7f	330	.gso_segment = ipv6_gso_segment,
fac8e0f5	331	.gro_receive = sit_gro_receive,
feec0cb3	332	.gro_complete = sit_gro_complete,
61c1db7f ED	333	},
	334	};
	335
c6b641a4	336	static int __init ipv6_offload_init(void)
d1da932e	337	{
c6b641a4 VY	338
	339	if (tcpv6_offload_init() < 0)
	340	pr_crit("%s: Cannot add TCP protocol offload\n", __func__);
c6b641a4 VY	341	if (ipv6_exthdrs_offload_init() < 0)
	342	pr_crit("%s: Cannot add EXTHDRS protocol offload\n", __func__);
	343
d1da932e	344	dev_add_offload(&ipv6_packet_offload);
61c1db7f ED	345
	346	inet_add_offload(&sit_offload, IPPROTO_IPV6);
	347
c6b641a4	348	return 0;
d1da932e VY	349	}
d1da932e VY	350
c6b641a4	351	fs_initcall(ipv6_offload_init);