gre: refactor the gre_fb_xmit

The patch refactors the gre_fb_xmit function, by creating
prepare_fb_xmit function for later ERSPAN collect_md mode patch.

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
William Tu 2017-08-25 09:21:27 -07:00 committed by David S. Miller
parent 03157937fe
commit 862a03c35e
1 changed files with 40 additions and 15 deletions

View File

@ -432,39 +432,33 @@ static struct rtable *gre_get_rt(struct sk_buff *skb,
return ip_route_output_key(net, fl);
}
static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
__be16 proto)
static struct rtable *prepare_fb_xmit(struct sk_buff *skb,
struct net_device *dev,
struct flowi4 *fl,
int tunnel_hlen)
{
struct ip_tunnel_info *tun_info;
const struct ip_tunnel_key *key;
struct rtable *rt = NULL;
struct flowi4 fl;
int min_headroom;
int tunnel_hlen;
__be16 df, flags;
bool use_cache;
int err;
tun_info = skb_tunnel_info(skb);
if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
ip_tunnel_info_af(tun_info) != AF_INET))
goto err_free_skb;
key = &tun_info->key;
use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
if (use_cache)
rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl.saddr);
rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl->saddr);
if (!rt) {
rt = gre_get_rt(skb, dev, &fl, key);
rt = gre_get_rt(skb, dev, fl, key);
if (IS_ERR(rt))
goto err_free_skb;
goto err_free_skb;
if (use_cache)
dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
fl.saddr);
fl->saddr);
}
tunnel_hlen = gre_calc_hlen(key->tun_flags);
min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
+ tunnel_hlen + sizeof(struct iphdr);
if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) {
@ -476,6 +470,37 @@ static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
if (unlikely(err))
goto err_free_rt;
}
return rt;
err_free_rt:
ip_rt_put(rt);
err_free_skb:
kfree_skb(skb);
dev->stats.tx_dropped++;
return NULL;
}
static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
__be16 proto)
{
struct ip_tunnel_info *tun_info;
const struct ip_tunnel_key *key;
struct rtable *rt = NULL;
struct flowi4 fl;
int tunnel_hlen;
__be16 df, flags;
tun_info = skb_tunnel_info(skb);
if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
ip_tunnel_info_af(tun_info) != AF_INET))
goto err_free_skb;
key = &tun_info->key;
tunnel_hlen = gre_calc_hlen(key->tun_flags);
rt = prepare_fb_xmit(skb, dev, &fl, tunnel_hlen);
if (!rt)
return;
/* Push Tunnel header. */
if (gre_handle_offloads(skb, !!(tun_info->key.tun_flags & TUNNEL_CSUM)))