diff options
| author | Vasily Averin <vvs@virtuozzo.com> | 2021-08-02 10:52:29 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-08-03 12:21:39 +0200 |
| commit | 0c9f227bee11910a49e1d159abe102d06e3745d5 (patch) | |
| tree | 2ad13f6808bb1275838cb8340ff09d366da3b81e | |
| parent | ipv6: use skb_expand_head in ip6_finish_output2 (diff) | |
| download | linux-0c9f227bee11910a49e1d159abe102d06e3745d5.tar.xz linux-0c9f227bee11910a49e1d159abe102d06e3745d5.zip | |
ipv6: use skb_expand_head in ip6_xmit
Unlike skb_realloc_headroom, new helper skb_expand_head
does not allocate a new skb if possible.
Additionally this patch replaces commonly used dereferencing with variables.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv6/ip6_output.c | 27 |
1 files changed, 11 insertions, 16 deletions
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 3fa58914d65d..12f985f43bcc 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -249,6 +249,8 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, const struct ipv6_pinfo *np = inet6_sk(sk); struct in6_addr *first_hop = &fl6->daddr; struct dst_entry *dst = skb_dst(skb); + struct net_device *dev = dst->dev; + struct inet6_dev *idev = ip6_dst_idev(dst); unsigned int head_room; struct ipv6hdr *hdr; u8 proto = fl6->flowi6_proto; @@ -256,22 +258,16 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, int hlimit = -1; u32 mtu; - head_room = sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev); + head_room = sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dev); if (opt) head_room += opt->opt_nflen + opt->opt_flen; - if (unlikely(skb_headroom(skb) < head_room)) { - struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room); - if (!skb2) { - IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), - IPSTATS_MIB_OUTDISCARDS); - kfree_skb(skb); + if (unlikely(head_room > skb_headroom(skb))) { + skb = skb_expand_head(skb, head_room); + if (!skb) { + IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS); return -ENOBUFS; } - if (skb->sk) - skb_set_owner_w(skb2, skb->sk); - consume_skb(skb); - skb = skb2; } if (opt) { @@ -313,8 +309,7 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, mtu = dst_mtu(dst); if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) { - IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)), - IPSTATS_MIB_OUT, skb->len); + IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len); /* if egress device is enslaved to an L3 master device pass the * skb to its handler for processing @@ -327,17 +322,17 @@ int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6, * we promote our socket to non const */ return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT, - net, (struct sock *)sk, skb, NULL, dst->dev, + net, (struct sock *)sk, skb, NULL, dev, dst_output); } - skb->dev = dst->dev; + skb->dev = dev; /* ipv6_local_error() does not require socket lock, * we promote our socket to non const */ ipv6_local_error((struct sock *)sk, EMSGSIZE, fl6, mtu); - IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS); + IP6_INC_STATS(net, idev, IPSTATS_MIB_FRAGFAILS); kfree_skb(skb); return -EMSGSIZE; } |