linux-toradex.git/net/ipv6/ip6_offload.c, branch v3.9.7 Linux kernel for Apalis and Colibri modules v4 GRE: Add TCP segmentation offload for GRE 2013-02-15T20:17:11+00:00 Pravin B Shelar pshelar@nicira.com 2013-02-14T14:02:41+00:00 68c331631143f5f039baac99a650e0b9e1ea02b6 Following patch adds GRE protocol offload handler so that skb_gso_segment() can segment GRE packets. SKB GSO CB is added to keep track of total header length so that skb_segment can push entire header. e.g. in case of GRE, skb_segment need to push inner and outer headers to every segment. New NETIF_F_GRE_GSO feature is added for devices which support HW GRE TSO offload. Currently none of devices support it therefore GRE GSO always fall backs to software GSO. [ Compute pkt_len before ip_local_out() invocation. -DaveM ] Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Following patch adds GRE protocol offload handler so that
skb_gso_segment() can segment GRE packets.
SKB GSO CB is added to keep track of total header length so that
skb_segment can push entire header. e.g. in case of GRE, skb_segment
need to push inner and outer headers to every segment.
New NETIF_F_GRE_GSO feature is added for devices which support HW
GRE TSO offload. Currently none of devices support it therefore GRE GSO
always fall backs to software GSO.

[ Compute pkt_len before ip_local_out() invocation. -DaveM ]

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: Fix possible wrong checksum generation. 2013-02-13T18:30:10+00:00 Pravin B Shelar pshelar@nicira.com 2013-02-11T09:27:41+00:00 c9af6db4c11ccc6c3e7f19bbc15d54023956f97c Patch cef401de7be8c4e (net: fix possible wrong checksum generation) fixed wrong checksum calculation but it broke TSO by defining new GSO type but not a netdev feature for that type. net_gso_ok() would not allow hardware checksum/segmentation offload of such packets without the feature. Following patch fixes TSO and wrong checksum. This patch uses same logic that Eric Dumazet used. Patch introduces new flag SKBTX_SHARED_FRAG if at least one frag can be modified by the user. but SKBTX_SHARED_FRAG flag is kept in skb shared info tx_flags rather than gso_type. tx_flags is better compared to gso_type since we can have skb with shared frag without gso packet. It does not link SHARED_FRAG to GSO, So there is no need to define netdev feature for this. Signed-off-by: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Patch cef401de7be8c4e (net: fix possible wrong checksum
generation) fixed wrong checksum calculation but it broke TSO by
defining new GSO type but not a netdev feature for that type.
net_gso_ok() would not allow hardware checksum/segmentation
offload of such packets without the feature.

Following patch fixes TSO and wrong checksum. This patch uses
same logic that Eric Dumazet used. Patch introduces new flag
SKBTX_SHARED_FRAG if at least one frag can be modified by
the user. but SKBTX_SHARED_FRAG flag is kept in skb shared
info tx_flags rather than gso_type.

tx_flags is better compared to gso_type since we can have skb with
shared frag without gso packet. It does not link SHARED_FRAG to
GSO, So there is no need to define netdev feature for this.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: fix possible wrong checksum generation 2013-01-28T05:27:15+00:00 Eric Dumazet edumazet@google.com 2013-01-25T20:34:37+00:00 cef401de7be8c4e155c6746bfccf721a4fa5fab9 Pravin Shelar mentioned that GSO could potentially generate wrong TX checksum if skb has fragments that are overwritten by the user between the checksum computation and transmit. He suggested to linearize skbs but this extra copy can be avoided for normal tcp skbs cooked by tcp_sendmsg(). This patch introduces a new SKB_GSO_SHARED_FRAG flag, set in skb_shinfo(skb)->gso_type if at least one frag can be modified by the user. Typical sources of such possible overwrites are {vm}splice(), sendfile(), and macvtap/tun/virtio_net drivers. Tested: $ netperf -H 7.7.8.84 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 3959.52 $ netperf -H 7.7.8.84 -t TCP_SENDFILE TCP SENDFILE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 () port 0 AF_INET Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 3216.80 Performance of the SENDFILE is impacted by the extra allocation and copy, and because we use order-0 pages, while the TCP_STREAM uses bigger pages. Reported-by: Pravin Shelar <pshelar@nicira.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Pravin Shelar mentioned that GSO could potentially generate
wrong TX checksum if skb has fragments that are overwritten
by the user between the checksum computation and transmit.

He suggested to linearize skbs but this extra copy can be
avoided for normal tcp skbs cooked by tcp_sendmsg().

This patch introduces a new SKB_GSO_SHARED_FRAG flag, set
in skb_shinfo(skb)->gso_type if at least one frag can be
modified by the user.

Typical sources of such possible overwrites are {vm}splice(),
sendfile(), and macvtap/tun/virtio_net drivers.

Tested:

$ netperf -H 7.7.8.84
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to
7.7.8.84 () port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.00    3959.52

$ netperf -H 7.7.8.84 -t TCP_SENDFILE
TCP SENDFILE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 ()
port 0 AF_INET
Recv   Send    Send
Socket Socket  Message  Elapsed
Size   Size    Size     Time     Throughput
bytes  bytes   bytes    secs.    10^6bits/sec

 87380  16384  16384    10.00    3216.80

Performance of the SENDFILE is impacted by the extra allocation and
copy, and because we use order-0 pages, while the TCP_STREAM uses
bigger pages.

Reported-by: Pravin Shelar <pshelar@nicira.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: Remove code duplication between offload structures 2012-11-15T22:39:51+00:00 Vlad Yasevich vyasevic@redhat.com 2012-11-15T08:49:23+00:00 f191a1d17f227032c159e5499809f545402b6dc6 Move the offload callbacks into its own structure. Signed-off-by: Vlad Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Move the offload callbacks into its own structure.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6: Pull IPv6 GSO registration out of the module 2012-11-15T22:39:24+00:00 Vlad Yasevich vyasevic@redhat.com 2012-11-15T08:49:22+00:00 c6b641a4c6b32f39db678c2441cb1ef824110d74 Sing GSO support is now separate, pull it out of the module and make it its own init call. Remove the cleanup functions as they are no longer called. Signed-off-by: Vlad Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Sing GSO support is now separate, pull it out of the module
and make it its own init call.
Remove the cleanup functions as they are no longer called.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ipv6: Separate ipv6 offload support 2012-11-15T22:36:17+00:00 Vlad Yasevich vyasevic@redhat.com 2012-11-15T08:49:16+00:00 d1da932ed4ecad2a14cbcc01ed589d617d0f0f09 Separate IPv6 offload functionality into its own file in preparation for the move out of the module Signed-off-by: Vlad Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Separate IPv6 offload functionality into its own file
in preparation for the move out of the module

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>