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| author | Steffen Klassert <steffen.klassert@secunet.com> | 2016-09-19 12:58:47 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-09-19 20:59:34 -0400 |
| commit | 07b26c9454a2a19fff86d6fcf2aba6bc801eb8d8 (patch) | |
| tree | 45cf751adb10dabaf383eaa07238c3427e3fe3f0 /net/core | |
| parent | e867e87ae88c54f741d1cabd1de536b4497a0504 (diff) | |
| download | linux-stable-07b26c9454a2a19fff86d6fcf2aba6bc801eb8d8.tar.gz linux-stable-07b26c9454a2a19fff86d6fcf2aba6bc801eb8d8.tar.bz2 linux-stable-07b26c9454a2a19fff86d6fcf2aba6bc801eb8d8.zip | |
gso: Support partial splitting at the frag_list pointer
Since commit 8a29111c7 ("net: gro: allow to build full sized skb")
gro may build buffers with a frag_list. This can hurt forwarding
because most NICs can't offload such packets, they need to be
segmented in software. This patch splits buffers with a frag_list
at the frag_list pointer into buffers that can be TSO offloaded.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/skbuff.c | 51 |
1 files changed, 40 insertions, 11 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 1e329d411242..7bf82a28e10a 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3097,11 +3097,31 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, sg = !!(features & NETIF_F_SG); csum = !!can_checksum_protocol(features, proto); - /* GSO partial only requires that we trim off any excess that - * doesn't fit into an MSS sized block, so take care of that - * now. - */ - if (sg && csum && (features & NETIF_F_GSO_PARTIAL)) { + if (sg && csum && (mss != GSO_BY_FRAGS)) { + if (!(features & NETIF_F_GSO_PARTIAL)) { + struct sk_buff *iter; + + if (!list_skb || + !net_gso_ok(features, skb_shinfo(head_skb)->gso_type)) + goto normal; + + /* Split the buffer at the frag_list pointer. + * This is based on the assumption that all + * buffers in the chain excluding the last + * containing the same amount of data. + */ + skb_walk_frags(head_skb, iter) { + if (skb_headlen(iter)) + goto normal; + + len -= iter->len; + } + } + + /* GSO partial only requires that we trim off any excess that + * doesn't fit into an MSS sized block, so take care of that + * now. + */ partial_segs = len / mss; if (partial_segs > 1) mss *= partial_segs; @@ -3109,6 +3129,7 @@ struct sk_buff *skb_segment(struct sk_buff *head_skb, partial_segs = 0; } +normal: headroom = skb_headroom(head_skb); pos = skb_headlen(head_skb); @@ -3300,21 +3321,29 @@ perform_csum_check: */ segs->prev = tail; - /* Update GSO info on first skb in partial sequence. */ if (partial_segs) { + struct sk_buff *iter; int type = skb_shinfo(head_skb)->gso_type; + unsigned short gso_size = skb_shinfo(head_skb)->gso_size; /* Update type to add partial and then remove dodgy if set */ - type |= SKB_GSO_PARTIAL; + type |= (features & NETIF_F_GSO_PARTIAL) / NETIF_F_GSO_PARTIAL * SKB_GSO_PARTIAL; type &= ~SKB_GSO_DODGY; /* Update GSO info and prepare to start updating headers on * our way back down the stack of protocols. */ - skb_shinfo(segs)->gso_size = skb_shinfo(head_skb)->gso_size; - skb_shinfo(segs)->gso_segs = partial_segs; - skb_shinfo(segs)->gso_type = type; - SKB_GSO_CB(segs)->data_offset = skb_headroom(segs) + doffset; + for (iter = segs; iter; iter = iter->next) { + skb_shinfo(iter)->gso_size = gso_size; + skb_shinfo(iter)->gso_segs = partial_segs; + skb_shinfo(iter)->gso_type = type; + SKB_GSO_CB(iter)->data_offset = skb_headroom(iter) + doffset; + } + + if (tail->len - doffset <= gso_size) + skb_shinfo(tail)->gso_size = 0; + else if (tail != segs) + skb_shinfo(tail)->gso_segs = DIV_ROUND_UP(tail->len - doffset, gso_size); } /* Following permits correct backpressure, for protocols |