mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-23 12:43:55 +08:00
cef401de7b
Pravin Shelar mentioned that GSO could potentially generate wrong TX checksum if skb has fragments that are overwritten by the user between the checksum computation and transmit. He suggested to linearize skbs but this extra copy can be avoided for normal tcp skbs cooked by tcp_sendmsg(). This patch introduces a new SKB_GSO_SHARED_FRAG flag, set in skb_shinfo(skb)->gso_type if at least one frag can be modified by the user. Typical sources of such possible overwrites are {vm}splice(), sendfile(), and macvtap/tun/virtio_net drivers. Tested: $ netperf -H 7.7.8.84 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 3959.52 $ netperf -H 7.7.8.84 -t TCP_SENDFILE TCP SENDFILE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 3216.80 Performance of the SENDFILE is impacted by the extra allocation and copy, and because we use order-0 pages, while the TCP_STREAM uses bigger pages. Reported-by: Pravin Shelar <pshelar@nicira.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
284 lines
6.4 KiB
C
284 lines
6.4 KiB
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;
|
|
|
|
proto = opth->nexthdr;
|
|
__skb_pull(skb, len);
|
|
}
|
|
|
|
return proto;
|
|
}
|
|
|
|
static int ipv6_gso_send_check(struct sk_buff *skb)
|
|
{
|
|
const struct ipv6hdr *ipv6h;
|
|
const struct net_offload *ops;
|
|
int err = -EINVAL;
|
|
|
|
if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
|
|
goto out;
|
|
|
|
ipv6h = ipv6_hdr(skb);
|
|
__skb_pull(skb, sizeof(*ipv6h));
|
|
err = -EPROTONOSUPPORT;
|
|
|
|
rcu_read_lock();
|
|
ops = rcu_dereference(inet6_offloads[
|
|
ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr)]);
|
|
|
|
if (likely(ops && ops->callbacks.gso_send_check)) {
|
|
skb_reset_transport_header(skb);
|
|
err = ops->callbacks.gso_send_check(skb);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
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;
|
|
u8 *prevhdr;
|
|
int offset = 0;
|
|
|
|
if (!(features & NETIF_F_V6_CSUM))
|
|
features &= ~NETIF_F_SG;
|
|
|
|
if (unlikely(skb_shinfo(skb)->gso_type &
|
|
~(SKB_GSO_UDP |
|
|
SKB_GSO_DODGY |
|
|
SKB_GSO_TCP_ECN |
|
|
SKB_GSO_TCPV6 |
|
|
SKB_GSO_SHARED_FRAG |
|
|
0)))
|
|
goto out;
|
|
|
|
if (unlikely(!pskb_may_pull(skb, sizeof(*ipv6h))))
|
|
goto out;
|
|
|
|
ipv6h = ipv6_hdr(skb);
|
|
__skb_pull(skb, sizeof(*ipv6h));
|
|
segs = ERR_PTR(-EPROTONOSUPPORT);
|
|
|
|
proto = ipv6_gso_pull_exthdrs(skb, ipv6h->nexthdr);
|
|
rcu_read_lock();
|
|
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);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (IS_ERR(segs))
|
|
goto out;
|
|
|
|
for (skb = segs; skb; skb = skb->next) {
|
|
ipv6h = ipv6_hdr(skb);
|
|
ipv6h->payload_len = htons(skb->len - skb->mac_len -
|
|
sizeof(*ipv6h));
|
|
if (proto == IPPROTO_UDP) {
|
|
unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
|
|
fptr = (struct frag_hdr *)(skb_network_header(skb) +
|
|
unfrag_ip6hlen);
|
|
fptr->frag_off = htons(offset);
|
|
if (skb->next != NULL)
|
|
fptr->frag_off |= htons(IP6_MF);
|
|
offset += (ntohs(ipv6h->payload_len) -
|
|
sizeof(struct frag_hdr));
|
|
}
|
|
}
|
|
|
|
out:
|
|
return segs;
|
|
}
|
|
|
|
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;
|
|
int flush = 1;
|
|
int proto;
|
|
__wsum csum;
|
|
|
|
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_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 = ipv6_hdr(p);
|
|
first_word = *(__be32 *)iph ^ *(__be32 *)iph2 ;
|
|
|
|
/* All fields must match except length and Traffic Class. */
|
|
if (nlen != skb_network_header_len(p) ||
|
|
(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;
|
|
}
|
|
|
|
NAPI_GRO_CB(skb)->flush |= flush;
|
|
|
|
csum = skb->csum;
|
|
skb_postpull_rcsum(skb, iph, skb_network_header_len(skb));
|
|
|
|
pp = ops->callbacks.gro_receive(head, skb);
|
|
|
|
skb->csum = csum;
|
|
|
|
out_unlock:
|
|
rcu_read_unlock();
|
|
|
|
out:
|
|
NAPI_GRO_CB(skb)->flush |= flush;
|
|
|
|
return pp;
|
|
}
|
|
|
|
static int ipv6_gro_complete(struct sk_buff *skb)
|
|
{
|
|
const struct net_offload *ops;
|
|
struct ipv6hdr *iph = ipv6_hdr(skb);
|
|
int err = -ENOSYS;
|
|
|
|
iph->payload_len = htons(skb->len - skb_network_offset(skb) -
|
|
sizeof(*iph));
|
|
|
|
rcu_read_lock();
|
|
ops = rcu_dereference(inet6_offloads[NAPI_GRO_CB(skb)->proto]);
|
|
if (WARN_ON(!ops || !ops->callbacks.gro_complete))
|
|
goto out_unlock;
|
|
|
|
err = ops->callbacks.gro_complete(skb);
|
|
|
|
out_unlock:
|
|
rcu_read_unlock();
|
|
|
|
return err;
|
|
}
|
|
|
|
static struct packet_offload ipv6_packet_offload __read_mostly = {
|
|
.type = cpu_to_be16(ETH_P_IPV6),
|
|
.callbacks = {
|
|
.gso_send_check = ipv6_gso_send_check,
|
|
.gso_segment = ipv6_gso_segment,
|
|
.gro_receive = ipv6_gro_receive,
|
|
.gro_complete = ipv6_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 (udp_offload_init() < 0)
|
|
pr_crit("%s: Cannot add UDP 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);
|
|
return 0;
|
|
}
|
|
|
|
fs_initcall(ipv6_offload_init);
|