diff options
author | Eric Dumazet <edumazet@google.com> | 2013-10-19 11:42:54 -0700 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2013-10-19 19:36:18 -0400 |
commit | 030737bcc3c404e273e97dbe06fe9561699a411b (patch) | |
tree | 95b56e3692c3f2704d7f41d70fb0627ae812ed2c /net/core/skbuff.c | |
parent | b917eb155c56bbb766140b406979820e719e3f55 (diff) |
net: generalize skb_segment()
While implementing GSO/TSO support for IPIP, I found skb_segment()
was assuming network header was immediately following mac header.
Its not really true in the case inet_gso_segment() is stacked :
By the time tcp_gso_segment() is called, network header points
to the inner IP header.
Let's instead assume nothing and pick the current offsets found in
original skb, we have skb_headers_offset_update() helper for that.
Also move the csum_start update inside skb_headers_offset_update()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/skbuff.c')
-rw-r--r-- | net/core/skbuff.c | 22 |
1 files changed, 5 insertions, 17 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 8ead744fcc9..0ab32faa520 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -903,6 +903,9 @@ EXPORT_SYMBOL(skb_clone); static void skb_headers_offset_update(struct sk_buff *skb, int off) { + /* Only adjust this if it actually is csum_start rather than csum */ + if (skb->ip_summed == CHECKSUM_PARTIAL) + skb->csum_start += off; /* {transport,network,mac}_header and tail are relative to skb->head */ skb->transport_header += off; skb->network_header += off; @@ -1109,9 +1112,6 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, #endif skb->tail += off; skb_headers_offset_update(skb, nhead); - /* Only adjust this if it actually is csum_start rather than csum */ - if (skb->ip_summed == CHECKSUM_PARTIAL) - skb->csum_start += nhead; skb->cloned = 0; skb->hdr_len = 0; skb->nohdr = 0; @@ -1176,7 +1176,6 @@ struct sk_buff *skb_copy_expand(const struct sk_buff *skb, NUMA_NO_NODE); int oldheadroom = skb_headroom(skb); int head_copy_len, head_copy_off; - int off; if (!n) return NULL; @@ -1200,11 +1199,7 @@ struct sk_buff *skb_copy_expand(const struct sk_buff *skb, copy_skb_header(n, skb); - off = newheadroom - oldheadroom; - if (n->ip_summed == CHECKSUM_PARTIAL) - n->csum_start += off; - - skb_headers_offset_update(n, off); + skb_headers_offset_update(n, newheadroom - oldheadroom); return n; } @@ -2837,14 +2832,7 @@ struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features) __copy_skb_header(nskb, skb); nskb->mac_len = skb->mac_len; - /* nskb and skb might have different headroom */ - if (nskb->ip_summed == CHECKSUM_PARTIAL) - nskb->csum_start += skb_headroom(nskb) - headroom; - - skb_reset_mac_header(nskb); - skb_set_network_header(nskb, skb->mac_len); - nskb->transport_header = (nskb->network_header + - skb_network_header_len(skb)); + skb_headers_offset_update(nskb, skb_headroom(nskb) - headroom); skb_copy_from_linear_data_offset(skb, -tnl_hlen, nskb->data - tnl_hlen, |