ipv6: Separate out UDP offload functionality

Pull UDP GSO code into a separate file in preparation for moving
the code out of the module.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Vlad Yasevich 2012-11-15 08:49:18 +00:00 committed by David S. Miller
parent 8663e02aba
commit 5edbb07dc9
4 changed files with 130 additions and 101 deletions

View file

@ -10,7 +10,7 @@ ipv6-objs := af_inet6.o anycast.o ip6_output.o ip6_input.o addrconf.o \
raw.o protocol.o icmp.o mcast.o reassembly.o tcp_ipv6.o \
exthdrs.o datagram.o ip6_flowlabel.o inet6_connection_sock.o
ipv6-offload := ip6_offload.o tcpv6_offload.o
ipv6-offload := ip6_offload.o tcpv6_offload.o udp_offload.o
ipv6-$(CONFIG_SYSCTL) = sysctl_net_ipv6.o
ipv6-$(CONFIG_IPV6_MROUTE) += ip6mr.o

View file

@ -11,6 +11,9 @@
#ifndef __ip6_offload_h
#define __ip6_offload_h
int udp_offload_init(void);
void udp_offload_cleanup(void);
int tcpv6_offload_init(void);
void tcpv6_offload_cleanup(void);

View file

@ -50,6 +50,7 @@
#include <linux/seq_file.h>
#include <trace/events/skb.h>
#include "udp_impl.h"
#include "ip6_offload.h"
int ipv6_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2)
{
@ -1343,109 +1344,12 @@ int compat_udpv6_getsockopt(struct sock *sk, int level, int optname,
}
#endif
static int udp6_ufo_send_check(struct sk_buff *skb)
{
const struct ipv6hdr *ipv6h;
struct udphdr *uh;
if (!pskb_may_pull(skb, sizeof(*uh)))
return -EINVAL;
ipv6h = ipv6_hdr(skb);
uh = udp_hdr(skb);
uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
IPPROTO_UDP, 0);
skb->csum_start = skb_transport_header(skb) - skb->head;
skb->csum_offset = offsetof(struct udphdr, check);
skb->ip_summed = CHECKSUM_PARTIAL;
return 0;
}
static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb,
netdev_features_t features)
{
struct sk_buff *segs = ERR_PTR(-EINVAL);
unsigned int mss;
unsigned int unfrag_ip6hlen, unfrag_len;
struct frag_hdr *fptr;
u8 *mac_start, *prevhdr;
u8 nexthdr;
u8 frag_hdr_sz = sizeof(struct frag_hdr);
int offset;
__wsum csum;
mss = skb_shinfo(skb)->gso_size;
if (unlikely(skb->len <= mss))
goto out;
if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
/* Packet is from an untrusted source, reset gso_segs. */
int type = skb_shinfo(skb)->gso_type;
if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
!(type & (SKB_GSO_UDP))))
goto out;
skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
segs = NULL;
goto out;
}
/* Do software UFO. Complete and fill in the UDP checksum as HW cannot
* do checksum of UDP packets sent as multiple IP fragments.
*/
offset = skb_checksum_start_offset(skb);
csum = skb_checksum(skb, offset, skb->len - offset, 0);
offset += skb->csum_offset;
*(__sum16 *)(skb->data + offset) = csum_fold(csum);
skb->ip_summed = CHECKSUM_NONE;
/* Check if there is enough headroom to insert fragment header. */
if ((skb_mac_header(skb) < skb->head + frag_hdr_sz) &&
pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
goto out;
/* Find the unfragmentable header and shift it left by frag_hdr_sz
* bytes to insert fragment header.
*/
unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
nexthdr = *prevhdr;
*prevhdr = NEXTHDR_FRAGMENT;
unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
unfrag_ip6hlen;
mac_start = skb_mac_header(skb);
memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
skb->mac_header -= frag_hdr_sz;
skb->network_header -= frag_hdr_sz;
fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
fptr->nexthdr = nexthdr;
fptr->reserved = 0;
ipv6_select_ident(fptr, (struct rt6_info *)skb_dst(skb));
/* Fragment the skb. ipv6 header and the remaining fields of the
* fragment header are updated in ipv6_gso_segment()
*/
segs = skb_segment(skb, features);
out:
return segs;
}
static const struct inet6_protocol udpv6_protocol = {
.handler = udpv6_rcv,
.err_handler = udpv6_err,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};
static const struct net_offload udpv6_offload = {
.gso_send_check = udp6_ufo_send_check,
.gso_segment = udp6_ufo_fragment,
};
/* ------------------------------------------------------------------------ */
#ifdef CONFIG_PROC_FS
@ -1568,7 +1472,7 @@ int __init udpv6_init(void)
{
int ret;
ret = inet6_add_offload(&udpv6_offload, IPPROTO_UDP);
ret = udp_offload_init();
if (ret)
goto out;
@ -1585,7 +1489,7 @@ int __init udpv6_init(void)
out_udpv6_protocol:
inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
out_offload:
inet6_del_offload(&udpv6_offload, IPPROTO_UDP);
udp_offload_cleanup();
goto out;
}
@ -1593,5 +1497,5 @@ void udpv6_exit(void)
{
inet6_unregister_protosw(&udpv6_protosw);
inet6_del_protocol(&udpv6_protocol, IPPROTO_UDP);
inet6_del_offload(&udpv6_offload, IPPROTO_UDP);
udp_offload_cleanup();
}

122
net/ipv6/udp_offload.c Normal file
View file

@ -0,0 +1,122 @@
/*
* 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.
*
* UDPv6 GSO support
*/
#include <linux/skbuff.h>
#include <net/protocol.h>
#include <net/ipv6.h>
#include <net/udp.h>
#include "ip6_offload.h"
static int udp6_ufo_send_check(struct sk_buff *skb)
{
const struct ipv6hdr *ipv6h;
struct udphdr *uh;
if (!pskb_may_pull(skb, sizeof(*uh)))
return -EINVAL;
ipv6h = ipv6_hdr(skb);
uh = udp_hdr(skb);
uh->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len,
IPPROTO_UDP, 0);
skb->csum_start = skb_transport_header(skb) - skb->head;
skb->csum_offset = offsetof(struct udphdr, check);
skb->ip_summed = CHECKSUM_PARTIAL;
return 0;
}
static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb,
netdev_features_t features)
{
struct sk_buff *segs = ERR_PTR(-EINVAL);
unsigned int mss;
unsigned int unfrag_ip6hlen, unfrag_len;
struct frag_hdr *fptr;
u8 *mac_start, *prevhdr;
u8 nexthdr;
u8 frag_hdr_sz = sizeof(struct frag_hdr);
int offset;
__wsum csum;
mss = skb_shinfo(skb)->gso_size;
if (unlikely(skb->len <= mss))
goto out;
if (skb_gso_ok(skb, features | NETIF_F_GSO_ROBUST)) {
/* Packet is from an untrusted source, reset gso_segs. */
int type = skb_shinfo(skb)->gso_type;
if (unlikely(type & ~(SKB_GSO_UDP | SKB_GSO_DODGY) ||
!(type & (SKB_GSO_UDP))))
goto out;
skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len, mss);
segs = NULL;
goto out;
}
/* Do software UFO. Complete and fill in the UDP checksum as HW cannot
* do checksum of UDP packets sent as multiple IP fragments.
*/
offset = skb_checksum_start_offset(skb);
csum = skb_checksum(skb, offset, skb->len - offset, 0);
offset += skb->csum_offset;
*(__sum16 *)(skb->data + offset) = csum_fold(csum);
skb->ip_summed = CHECKSUM_NONE;
/* Check if there is enough headroom to insert fragment header. */
if ((skb_mac_header(skb) < skb->head + frag_hdr_sz) &&
pskb_expand_head(skb, frag_hdr_sz, 0, GFP_ATOMIC))
goto out;
/* Find the unfragmentable header and shift it left by frag_hdr_sz
* bytes to insert fragment header.
*/
unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
nexthdr = *prevhdr;
*prevhdr = NEXTHDR_FRAGMENT;
unfrag_len = skb_network_header(skb) - skb_mac_header(skb) +
unfrag_ip6hlen;
mac_start = skb_mac_header(skb);
memmove(mac_start-frag_hdr_sz, mac_start, unfrag_len);
skb->mac_header -= frag_hdr_sz;
skb->network_header -= frag_hdr_sz;
fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen);
fptr->nexthdr = nexthdr;
fptr->reserved = 0;
ipv6_select_ident(fptr, (struct rt6_info *)skb_dst(skb));
/* Fragment the skb. ipv6 header and the remaining fields of the
* fragment header are updated in ipv6_gso_segment()
*/
segs = skb_segment(skb, features);
out:
return segs;
}
static const struct net_offload udpv6_offload = {
.gso_send_check = udp6_ufo_send_check,
.gso_segment = udp6_ufo_fragment,
};
int __init udp_offload_init(void)
{
return inet6_add_offload(&udpv6_offload, IPPROTO_UDP);
}
void udp_offload_cleanup(void)
{
inet6_del_offload(&udpv6_offload, IPPROTO_UDP);
}