ipv4: gso: make inet_gso_segment() stackable

In order to support GSO on IPIP, we need to make
inet_gso_segment() stackable.

It should not assume network header starts right after mac
header.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2013-10-19 11:42:56 -07:00 committed by David S. Miller
parent 2d26f0a3c0
commit 3347c96029
3 changed files with 25 additions and 9 deletions

View File

@ -2722,9 +2722,12 @@ static inline struct sec_path *skb_sec_path(struct sk_buff *skb)
/* Keeps track of mac header offset relative to skb->head.
* It is useful for TSO of Tunneling protocol. e.g. GRE.
* For non-tunnel skb it points to skb_mac_header() and for
* tunnel skb it points to outer mac header. */
* tunnel skb it points to outer mac header.
* Keeps track of level of encapsulation of network headers.
*/
struct skb_gso_cb {
int mac_offset;
int mac_offset;
int encap_level;
};
#define SKB_GSO_CB(skb) ((struct skb_gso_cb *)(skb)->cb)

View File

@ -2377,6 +2377,8 @@ struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
}
SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
SKB_GSO_CB(skb)->encap_level = 0;
skb_reset_mac_header(skb);
skb_reset_mac_len(skb);

View File

@ -1273,16 +1273,17 @@ out:
}
static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
netdev_features_t features)
netdev_features_t features)
{
struct sk_buff *segs = ERR_PTR(-EINVAL);
const struct net_offload *ops;
unsigned int offset = 0;
struct iphdr *iph;
bool tunnel;
int proto;
int nhoff;
int ihl;
int id;
unsigned int offset = 0;
bool tunnel;
if (unlikely(skb_shinfo(skb)->gso_type &
~(SKB_GSO_TCPV4 |
@ -1296,6 +1297,8 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
0)))
goto out;
skb_reset_network_header(skb);
nhoff = skb_network_header(skb) - skb_mac_header(skb);
if (unlikely(!pskb_may_pull(skb, sizeof(*iph))))
goto out;
@ -1312,7 +1315,10 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
goto out;
__skb_pull(skb, ihl);
tunnel = !!skb->encapsulation;
tunnel = SKB_GSO_CB(skb)->encap_level > 0;
if (tunnel)
features = skb->dev->hw_enc_features & netif_skb_features(skb);
SKB_GSO_CB(skb)->encap_level += ihl;
skb_reset_transport_header(skb);
@ -1327,18 +1333,23 @@ static struct sk_buff *inet_gso_segment(struct sk_buff *skb,
skb = segs;
do {
iph = ip_hdr(skb);
iph = (struct iphdr *)(skb_mac_header(skb) + nhoff);
if (!tunnel && proto == IPPROTO_UDP) {
iph->id = htons(id);
iph->frag_off = htons(offset >> 3);
if (skb->next != NULL)
iph->frag_off |= htons(IP_MF);
offset += (skb->len - skb->mac_len - iph->ihl * 4);
offset += skb->len - nhoff - ihl;
} else {
iph->id = htons(id++);
}
iph->tot_len = htons(skb->len - skb->mac_len);
iph->tot_len = htons(skb->len - nhoff);
ip_send_check(iph);
if (tunnel) {
skb_reset_inner_headers(skb);
skb->encapsulation = 1;
}
skb->network_header = (u8 *)iph - skb->head;
} while ((skb = skb->next));
out: