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| author | David S. Miller <davem@davemloft.net> | 2016-02-12 05:52:41 -0500 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-02-12 05:52:41 -0500 |
| commit | 667f00630ebefc4d73aa105c6ab254e4aec867f8 (patch) | |
| tree | e8898fbf9bcbf38de21be4e89b93eed0816a6c52 /include/linux | |
| parent | e51271d4ce7b229f5c02903e3c44bf92c0dbef6b (diff) | |
| parent | e8ae7b000e64cf76283c72cae5e3ecd246618ef4 (diff) | |
Merge branch 'local-checksum-offload'
Edward Cree says:
====================
Local Checksum Offload
Re-tested VxLAN; everything else is unchanged from v4.
Changes from v4:
* Rebased series to fix conflicts with vxlan/vxlan6 merge.
Changes from v3:
* Fixed inverted checksum values introduced in v3.
* Don't mangle zero checksums in GRE.
* Clear skb->encapsulation in iptunnel_handle_offloads when not using
CHECKSUM_PARTIAL, lest drivers incorrectly interpret that as a request
for inner checksum offload.
Changes from v2:
* Added support for IPv4 GRE.
* Split out 'always set up for checksum offload' into its own patch.
* Removed csum_help from iptunnel_handle_offloads.
* Rewrote LCO callers to only fold once.
* Simplified nocheck handling.
Changes from v1:
* Enabled support in more encapsulation protocols.
I think it now covers everything except GRE.
* Wrote up some documentation covering TX checksum offload, LCO and RCO.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/skbuff.h | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 6ec86f1a2ed9..39206751463e 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -3702,5 +3702,31 @@ static inline unsigned int skb_gso_network_seglen(const struct sk_buff *skb) return hdr_len + skb_gso_transport_seglen(skb); } +/* Local Checksum Offload. + * Compute outer checksum based on the assumption that the + * inner checksum will be offloaded later. + * See Documentation/networking/checksum-offloads.txt for + * explanation of how this works. + * Fill in outer checksum adjustment (e.g. with sum of outer + * pseudo-header) before calling. + * Also ensure that inner checksum is in linear data area. + */ +static inline __wsum lco_csum(struct sk_buff *skb) +{ + char *inner_csum_field; + __wsum csum; + + /* Start with complement of inner checksum adjustment */ + inner_csum_field = skb->data + skb_checksum_start_offset(skb) + + skb->csum_offset; + csum = ~csum_unfold(*(__force __sum16 *)inner_csum_field); + /* Add in checksum of our headers (incl. outer checksum + * adjustment filled in by caller) + */ + csum = skb_checksum(skb, 0, skb_checksum_start_offset(skb), csum); + /* The result is the checksum from skb->data to end of packet */ + return csum; +} + #endif /* __KERNEL__ */ #endif /* _LINUX_SKBUFF_H */ |