linux_dsm_epyc7002/net
Simon Horman 0d89d2035f MPLS: Add limited GSO support
In the case where a non-MPLS packet is received and an MPLS stack is
added it may well be the case that the original skb is GSO but the
NIC used for transmit does not support GSO of MPLS packets.

The aim of this code is to provide GSO in software for MPLS packets
whose skbs are GSO.

SKB Usage:

When an implementation adds an MPLS stack to a non-MPLS packet it should do
the following to skb metadata:

* Set skb->inner_protocol to the old non-MPLS ethertype of the packet.
  skb->inner_protocol is added by this patch.

* Set skb->protocol to the new MPLS ethertype of the packet.

* Set skb->network_header to correspond to the
  end of the L3 header, including the MPLS label stack.

I have posted a patch, "[PATCH v3.29] datapath: Add basic MPLS support to
kernel" which adds MPLS support to the kernel datapath of Open vSwtich.
That patch sets the above requirements in datapath/actions.c:push_mpls()
and was used to exercise this code.  The datapath patch is against the Open
vSwtich tree but it is intended that it be added to the Open vSwtich code
present in the mainline Linux kernel at some point.

Features:

I believe that the approach that I have taken is at least partially
consistent with the handling of other protocols.  Jesse, I understand that
you have some ideas here.  I am more than happy to change my implementation.

This patch adds dev->mpls_features which may be used by devices
to advertise features supported for MPLS packets.

A new NETIF_F_MPLS_GSO feature is added for devices which support
hardware MPLS GSO offload.  Currently no devices support this
and MPLS GSO always falls back to software.

Alternate Implementation:

One possible alternate implementation is to teach netif_skb_features()
and skb_network_protocol() about MPLS, in a similar way to their
understanding of VLANs. I believe this would avoid the need
for net/mpls/mpls_gso.c and in particular the calls to
__skb_push() and __skb_push() in mpls_gso_segment().

I have decided on the implementation in this patch as it should
not introduce any overhead in the case where mpls_gso is not compiled
into the kernel or inserted as a module.

MPLS GSO suggested by Jesse Gross.
Based in part on "v4 GRE: Add TCP segmentation offload for GRE"
by Pravin B Shelar.

Cc: Jesse Gross <jesse@nicira.com>
Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-05-27 22:50:59 -07:00
..
9p Lots of virtio work which wasn't quite ready for last merge window. Plus 2013-05-02 14:14:04 -07:00
802 net/802/mrp: fix lockdep splat 2013-05-14 13:02:30 -07:00
8021q net: vlan,ethtool: netdev_features_t is more than 32 bit 2013-05-02 13:58:12 -04:00
appletalk appletalk: info leak in ->getname() 2013-04-25 01:47:58 -04:00
atm Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
ax25 ax25: fix info leak via msg_name in ax25_recvmsg() 2013-04-07 16:28:00 -04:00
batman-adv batman-adv: Avoid double freeing of bat_counters 2013-05-21 21:34:36 +02:00
bluetooth Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
bridge Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-05-24 16:48:28 -07:00
caif caif: Remove bouncing address for Daniel Martensson 2013-04-23 13:25:51 -04:00
can Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
ceph libceph: init sent and completed when starting 2013-05-13 12:52:23 -05:00
core MPLS: Add limited GSO support 2013-05-27 22:50:59 -07:00
dcb rtnetlink: Remove passing of attributes into rtnl_doit functions 2013-03-22 10:31:16 -04:00
dccp tcp: Remove TCPCT 2013-03-17 14:35:13 -04:00
decnet decnet: remove duplicated include from dn_table.c 2013-04-07 17:12:01 -04:00
dns_resolver Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2012-12-16 15:40:50 -08:00
dsa dsa: fix freeing of sparse port allocation 2013-03-25 12:23:41 -04:00
ethernet net: add ETH_P_802_3_MIN 2013-03-28 01:20:42 -04:00
ieee802154 ieee802154/nl-mac.c: make some MLME operations optional 2013-04-08 12:00:16 -04:00
ipv4 MPLS: Add limited GSO support 2013-05-27 22:50:59 -07:00
ipv6 MPLS: Add limited GSO support 2013-05-27 22:50:59 -07:00
ipx hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
irda net: irda: using kzalloc() instead of kmalloc() to avoid strncpy() issue. 2013-05-19 15:10:47 -07:00
iucv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-22 20:32:51 -04:00
key Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec 2013-03-27 14:07:04 -04:00
l2tp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-07 18:37:01 -04:00
lapb net/lapb: remove depends on CONFIG_EXPERIMENTAL 2013-01-11 11:40:01 -08:00
llc llc: Fix missing msg_namelen update in llc_ui_recvmsg() 2013-04-07 16:28:01 -04:00
mac80211 mac80211: report deauth to cfg80211 for local state change 2013-05-16 22:38:08 +02:00
mac802154 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-30 03:55:20 -04:00
mpls MPLS: Add limited GSO support 2013-05-27 22:50:59 -07:00
netfilter netfilter: xt_TCPOPTSTRIP: fix possible mangling beyond packet boundary 2013-05-16 17:35:53 +02:00
netlabel netlabel: improve domain mapping validation 2013-05-19 14:49:55 -07:00
netlink netlink: kconfig: move mmap i/o into netlink kconfig 2013-05-01 15:02:42 -04:00
netrom netrom: info leak in ->getname() 2013-04-25 01:47:58 -04:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-30 03:55:20 -04:00
openvswitch openvswitch: Remove unneeded ovs_netdev_get_ifindex() 2013-04-30 00:19:11 -04:00
packet packet: tpacket_v3: do not trigger bug() on wrong header status 2013-05-03 16:10:33 -04:00
phonet rtnetlink: Remove passing of attributes into rtnl_doit functions 2013-03-22 10:31:16 -04:00
rds net/rds: zero last byte for strncpy 2013-03-08 00:35:44 -05:00
rfkill Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next 2013-04-22 14:58:14 -04:00
rose rose: fix info leak via msg_name in rose_recvmsg() 2013-04-07 16:28:02 -04:00
rxrpc Driver core patches for 3.9-rc1 2013-02-21 12:05:51 -08:00
sched sch_tbf: segment too big GSO packets 2013-05-23 00:06:40 -07:00
sctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-05-01 14:08:52 -07:00
sunrpc Merge branch 'for-3.10' of git://linux-nfs.org/~bfields/linux 2013-05-10 09:28:55 -07:00
tipc tipc: potential divide by zero in tipc_link_recv_fragment() 2013-05-06 16:16:52 -04:00
unix af_unix: fix a fatal race with bit fields 2013-05-01 15:13:49 -04:00
vmw_vsock Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2013-04-30 03:55:20 -04:00
wimax
wireless cfg80211: fix sending WoWLAN TCP wakeup settings 2013-05-16 22:38:09 +02:00
x25 x25: use proc_remove_subtree() 2013-04-09 14:13:35 -04:00
xfrm xfrm: properly handle invalid states as an error 2013-05-23 01:20:07 -07:00
compat.c
Kconfig MPLS: Add limited GSO support 2013-05-27 22:50:59 -07:00
Makefile MPLS: Add limited GSO support 2013-05-27 22:50:59 -07:00
nonet.c
socket.c Merge git://git.infradead.org/users/eparis/audit 2013-05-11 14:29:11 -07:00
sysctl_net.c