Commit Graph

93 Commits

Author SHA1 Message Date
Haishuang Yan 252f3f5a11 ip6_gre: Set flowi6_proto as IPPROTO_GRE in xmit path.
In gre6 xmit path, we are sending a GRE packet, so set fl6 proto
to IPPROTO_GRE properly.

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-24 14:33:48 -07:00
Haishuang Yan 1b227e5366 ip6_gre: Fix MTU setting for ip6gretap
When creat an ip6gretap interface with an unreachable route,
the MTU is about 14 bytes larger than what was needed.

If the remote address is reachable:
ping6 2001:0:130::1 -c 2
PING 2001:0:130::1(2001:0:130::1) 56 data bytes
64 bytes from 2001:0:130::1: icmp_seq=1 ttl=64 time=1.46 ms
64 bytes from 2001:0:130::1: icmp_seq=2 ttl=64 time=81.1 ms

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-24 14:33:48 -07:00
Alexander Duyck 6a55368101 ip6_gre: Do not allow segmentation offloads GRE_CSUM is enabled with FOU/GUE
This patch addresses the same issue we had for IPv4 where enabling GRE with
an inner checksum cannot be supported with FOU/GUE due to the fact that
they will jump past the GRE header at it is treated like a tunnel header.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-20 19:25:52 -04:00
Tom Herbert 1faf3d9f7c ip6_gre: Add support for fou/gue encapsulation
Add netlink and setup for encapsulation

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-20 18:03:16 -04:00
Haishuang Yan da73b4e953 gre: Fix wrong tpi->proto in WCCP
When dealing with WCCP in gre6 tunnel, it sets the wrong tpi->protocol,
that is, ETH_P_IP instead of ETH_P_IPV6 for the encapuslated traffic.

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-12 16:53:58 -04:00
Haishuang Yan 23f72215bc ip6_gre: Fix get_size calculation for gre6 tunnel
Do not include attribute IFLA_GRE_TOS.

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-12 16:53:58 -04:00
Tom Herbert b45bd1d787 ip6_gre: Use correct flags for reading TUNNEL_SEQ
Fix two spots where o_flags in a tunnel are being compared to GRE_SEQ
instead of TUNNEL_SEQ.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-10 00:39:27 -04:00
Tom Herbert d27bff9ca2 ip6_gre: Set inner protocol correctly in __gre6_xmit
Need to use adjusted protocol value for setting inner protocol.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-10 00:39:27 -04:00
Tom Herbert f41fe3c2ac gre6: Fix flag translations
GRE for IPv6 does not properly translate for GRE flags to tunnel
flags and vice versa. This patch fixes that.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-10 00:39:27 -04:00
Tom Herbert db2ec95d1b ip6_gre: Fix MTU setting
In ip6gre_tnl_link_config set t->tun_len and t->hlen correctly for the
configuration. For hard_header_len and mtu calculation include
IPv6 header and encapsulation overhead.

In ip6gre_tunnel_init_common set t->tun_len and t->hlen correctly for
the configuration. Revert to setting hard_header_len instead of
needed_headroom.

Tested:

./ip link add name tun8 type ip6gretap remote \
2401:db00:20:911a:face:0:27:0 local \
2401:db00:20:911a:face:0:25:0 ttl 225

Gives MTU of 1434. That is equal to 1500 - 40 - 14 - 4 - 8.

./ip link add name tun8 type ip6gretap remote \
2401:db00:20:911a:face:0:27:0 local \
2401:db00:20:911a:face:0:25:0 ttl 225 okey 123

Gives MTU of 1430. That is equal to 1500 - 40 - 14 - 4 - 8 - 4.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-10 00:39:27 -04:00
Jiri Benc f132ae7c46 gre: change gre_parse_header to return the header length
It's easier for gre_parse_header to return the header length instead of
filing it into a parameter. That way, the callers that don't care about the
header length can just check whether the returned value is lower than zero.

In gre_err, the tunnel header must not be pulled. See commit b7f8fe251e
("gre: do not pull header in ICMP error processing") for details.

This patch reduces the conflict between the mentioned commit and commit
95f5c64c3c ("gre: Move utility functions to common headers").

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-04 12:44:45 -04:00
Tom Herbert b05229f442 gre6: Cleanup GREv6 transmit path, call common GRE functions
Changes in GREv6 transmit path:
  - Call gre_checksum, remove gre6_checksum
  - Rename ip6gre_xmit2 to __gre6_xmit
  - Call gre_build_header utility function
  - Call ip6_tnl_xmit common function
  - Call ip6_tnl_change_mtu, eliminate ip6gre_tunnel_change_mtu

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-02 19:23:32 -04:00
Tom Herbert 308edfdf15 gre6: Cleanup GREv6 receive path, call common GRE functions
- Create gre_rcv function. This calls gre_parse_header and ip6gre_rcv.
  - Call ip6_tnl_rcv. Doing this and using gre_parse_header eliminates
    most of the code in ip6gre_rcv.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-02 19:23:31 -04:00
Alexander Duyck 3a80e1facd ip6gre: Add support for GSO
This patch adds code borrowed from bits and pieces of other protocols to
the IPv6 GRE path so that we can support GSO over IPv6 based GRE tunnels.
By adding this support we are able to significantly improve the throughput
for GRE tunnels as we are able to make use of GSO.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-16 19:09:13 -04:00
Alexander Duyck ac4eb009e4 ip6gre: Add support for basic offloads offloads excluding GSO
This patch adds support for the basic offloads we support on most devices.
Specifically with this patch set we can support checksum offload, basic
scatter-gather, and highdma.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-16 19:09:13 -04:00
Alexander Duyck a9e242ca43 ip6gretap: Fix MTU to allow for Ethernet header
When we were creating an ip6gretap interface the MTU was about 6 bytes
short of what was needed.  It turns out we were not taking the Ethernet
header into account and as a result we were eating into the 8 bytes
reserved for the encap limit.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-16 19:09:13 -04:00
David S. Miller 810813c47a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of overlapping changes, as well as one instance
(vxlan) of a bug fix in 'net' overlapping with code movement
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-08 12:34:12 -05:00
Bernie Harris 5146d1f151 tunnel: Clear IPCB(skb)->opt before dst_link_failure called
IPCB may contain data from previous layers (in the observed case the
qdisc layer). In the observed scenario, the data was misinterpreted as
ip header options, which later caused the ihl to be set to an invalid
value (<5). This resulted in an infinite loop in the mips implementation
of ip_fast_csum.

This patch clears IPCB(skb)->opt before dst_link_failure can be called for
various types of tunnels. This change only applies to encapsulated ipv4
packets.

The code introduced in 11c21a30 which clears all of IPCB has been removed
to be consistent with these changes, and instead the opt field is cleared
unconditionally in ip_tunnel_xmit. The change in ip_tunnel_xmit applies to
SIT, GRE, and IPIP tunnels.

The relevant vti, l2tp, and pptp functions already contain similar code for
clearing the IPCB.

Signed-off-by: Bernie Harris <bernie.harris@alliedtelesis.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-23 19:11:56 -05:00
David S. Miller b633353115 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/phy/bcm7xxx.c
	drivers/net/phy/marvell.c
	drivers/net/vxlan.c

All three conflicts were cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-23 00:09:14 -05:00
Jiri Benc d13b161c2c gre: clear IFF_TX_SKB_SHARING
ether_setup sets IFF_TX_SKB_SHARING but this is not supported by gre
as it modifies the skb on xmit.

Also, clean up whitespace in ipgre_tap_setup when we're already touching it.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-18 14:43:48 -05:00
Paolo Abeni 607f725f6f net: replace dst_cache ip6_tunnel implementation with the generic one
This also fix a potential race into the existing tunnel code, which
could lead to the wrong dst to be permanenty cached:

CPU1:					CPU2:
  <xmit on ip6_tunnel>
  <cache lookup fails>
  dst = ip6_route_output(...)
					<tunnel params are changed via nl>
					dst_cache_reset() // no effect,
							// the cache is empty
  dst_cache_set() // the wrong dst
	// is permanenty stored
	// into the cache

With the new dst implementation the above race is not possible
since the first cache lookup after dst_cache_reset will fail due
to the timestamp check

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Suggested-and-acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-02-16 20:21:48 -05:00
David S. Miller b3e0d3d7ba Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/geneve.c

Here we had an overlapping change, where in 'net' the extraneous stats
bump was being removed whilst in 'net-next' the final argument to
udp_tunnel6_xmit_skb() was being changed.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-17 22:08:28 -05:00
Nicolas Dichtel 6a61d4dbf4 gre6: allow to update all parameters via rtnl
Parameters were updated only if the kernel was unable to find the tunnel
with the new parameters, ie only if core pamareters were updated (keys,
addr, link, type).
Now it's possible to update ttl, hoplimit, flowinfo and flags.

Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-04 16:52:06 -05:00
Nikolay Aleksandrov dfc3b0e891 net: remove unnecessary mroute.h includes
It looks like many files are including mroute.h unnecessarily, so remove
the include. Most importantly remove it from ipv6.

CC: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
CC: Steffen Klassert <steffen.klassert@secunet.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-30 15:26:21 -05:00
Matt Bennett a46496ce38 ip6_gre: Reduce log level in ip6gre_err() to debug
Currently error log messages in ip6gre_err are printed at 'warn'
level. This is different to most other tunnel types which don't
print any messages. These log messages don't provide any information
that couldn't be deduced with networking tools. Also it can be annoying
to have one end of the tunnel go down and have the logs fill with
pointless messages such as "Path to destination invalid or inactive!".

This patch reduces the log level of these messages to 'dbg' level to
bring the visible behaviour into line with other tunnel types.

Signed-off-by: Matt Bennett <matt.bennett@alliedtelesis.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24 15:28:43 -07:00
Martin KaFai Lau cdf3464e6c ipv6: Fix dst_entry refcnt bugs in ip6_tunnel
Problems in the current dst_entry cache in the ip6_tunnel:

1. ip6_tnl_dst_set is racy.  There is no lock to protect it:
   - One major problem is that the dst refcnt gets messed up. F.e.
     the same dst_cache can be released multiple times and then
     triggering the infamous dst refcnt < 0 warning message.
   - Another issue is the inconsistency between dst_cache and
     dst_cookie.

   It can be reproduced by adding and removing the ip6gre tunnel
   while running a super_netperf TCP_CRR test.

2. ip6_tnl_dst_get does not take the dst refcnt before returning
   the dst.

This patch:
1. Create a percpu dst_entry cache in ip6_tnl
2. Use a spinlock to protect the dst_cache operations
3. ip6_tnl_dst_get always takes the dst refcnt before returning

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-15 14:53:05 -07:00
Martin KaFai Lau f230d1e891 ipv6: Rename the dst_cache helper functions in ip6_tunnel
It is a prep work to fix the dst_entry refcnt bugs in
ip6_tunnel.

This patch rename:
1. ip6_tnl_dst_check() to ip6_tnl_dst_get() to better
   reflect that it will take a dst refcnt in the next patch.
2. ip6_tnl_dst_store() to ip6_tnl_dst_set() to have a more
   conventional name matching with ip6_tnl_dst_get().

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-15 14:53:04 -07:00
Martin KaFai Lau a3c119d392 ipv6: Refactor common ip6gre_tunnel_init codes
It is a prep work to fix the dst_entry refcnt bugs in ip6_tunnel.

This patch refactors some common init codes used by both
ip6gre_tunnel_init and ip6gre_tap_init.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-15 14:53:04 -07:00
David S. Miller 0d36938bb8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-08-27 21:45:31 -07:00
huaibin Wang d4257295ba ip6_gre: release cached dst on tunnel removal
When a tunnel is deleted, the cached dst entry should be released.

This problem may prevent the removal of a netns (seen with a x-netns IPv6
gre tunnel):
  unregister_netdevice: waiting for lo to become free. Usage count = 3

CC: Dmitry Kozlov <xeb@mail.ru>
Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Signed-off-by: huaibin Wang <huaibin.wang@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-25 14:33:00 -07:00
Tom Herbert 42240901f7 ipv6: Implement different admin modes for automatic flow labels
Change the meaning of net.ipv6.auto_flowlabels to provide a mode for
automatic flow labels generation. There are four modes:

0: flow labels are disabled
1: flow labels are enabled, sockets can opt-out
2: flow labels are allowed, sockets can opt-in
3: flow labels are enabled and enforced, no opt-out for sockets

np->autoflowlabel is initialized according to the sysctl value.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 17:07:11 -07:00
Tom Herbert 67800f9b1f ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel
We can't call skb_get_hash here since the packet is not complete to do
flow_dissector. Create hash based on flowi6 instead.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 17:07:11 -07:00
Johannes Berg 26349c71b4 ip6_gre: use netdev_alloc_pcpu_stats()
The code there just open-codes the same, so use the provided macro instead.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-22 15:39:05 -04:00
David Miller 79b16aadea udp_tunnel: Pass UDP socket down through udp_tunnel{, 6}_xmit_skb().
That was we can make sure the output path of ipv4/ipv6 operate on
the UDP socket rather than whatever random thing happens to be in
skb->sk.

Based upon a patch by Jiri Pirko.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
2015-04-07 15:29:08 -04:00
Nicolas Dichtel ecf2c06a88 ip6tnl,gre6,vti6: implement ndo_get_iflink
Don't use dev->iflink anymore.

CC: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-02 14:04:59 -04:00
Jiri Benc 67b61f6c13 netlink: implement nla_get_in_addr and nla_get_in6_addr
Those are counterparts to nla_put_in_addr and nla_put_in6_addr.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:58:35 -04:00
Jiri Benc 930345ea63 netlink: implement nla_put_in_addr and nla_put_in6_addr
IP addresses are often stored in netlink attributes. Add generic functions
to do that.

For nla_put_in_addr, it would be nicer to pass struct in_addr but this is
not used universally throughout the kernel, in way too many places __be32 is
used to store IPv4 address.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:58:35 -04:00
Ian Morris 53b24b8f94 ipv6: coding style: comparison for inequality with NULL
The ipv6 code uses a mixture of coding styles. In some instances check for NULL
pointer is done as x != NULL and sometimes as x. x is preferred according to
checkpatch and this patch makes the code consistent by adopting the latter
form.

No changes detected by objdiff.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:51:54 -04:00
Ian Morris 63159f29be ipv6: coding style: comparison for equality with NULL
The ipv6 code uses a mixture of coding styles. In some instances check for NULL
pointer is done as x == NULL and sometimes as !x. !x is preferred according to
checkpatch and this patch makes the code consistent by adopting the latter
form.

No changes detected by objdiff.

Signed-off-by: Ian Morris <ipm@chirality.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-31 13:51:54 -04:00
David S. Miller 6e03f896b5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/vxlan.c
	drivers/vhost/net.c
	include/linux/if_vlan.h
	net/core/dev.c

The net/core/dev.c conflict was the overlap of one commit marking an
existing function static whilst another was adding a new function.

In the include/linux/if_vlan.h case, the type used for a local
variable was changed in 'net', whereas the function got rewritten
to fix a stacked vlan bug in 'net-next'.

In drivers/vhost/net.c, Al Viro's iov_iter conversions in 'net-next'
overlapped with an endainness fix for VHOST 1.0 in 'net'.

In drivers/net/vxlan.c, vxlan_find_vni() added a 'flags' parameter
in 'net-next' whereas in 'net' there was a bug fix to pass in the
correct network namespace pointer in calls to this function.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05 14:33:28 -08:00
Sabrina Dubroca d1e158e2d7 ip6_gre: fix endianness errors in ip6gre_err
info is in network byte order, change it back to host byte order
before use. In particular, the current code sets the MTU of the tunnel
to a wrong (too big) value.

Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05 00:33:10 -08:00
Nicolas Dichtel 3390e39761 ip6gretap: advertise link netns via netlink
Assign rtnl_link_ops->get_link_net() callback so that IFLA_LINK_NETNSID is
added to rtnetlink messages.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-23 17:51:14 -08:00
Nicolas Dichtel 1728d4fabd tunnels: advertise link netns via netlink
Implement rtnl_link_ops->get_link_net() callback so that IFLA_LINK_NETNSID is
added to rtnetlink messages.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-19 14:32:03 -05:00
David S. Miller 60b7379dc5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-11-29 20:47:48 -08:00
Yuri Chislov be6572fdb1 ipv6: gre: fix wrong skb->protocol in WCCP
When using GRE redirection in WCCP, it sets the wrong skb->protocol,
that is, ETH_P_IP instead of ETH_P_IPV6 for the encapuslated traffic.

Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Cc: Dmitry Kozlov <xeb@mail.ru>
Signed-off-by: Yuri Chislov <yuri.chislov@gmail.com>
Tested-by: Yuri Chislov <yuri.chislov@gmail.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-24 16:11:05 -05:00
David S. Miller 4e84b496fd Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-11-06 22:01:18 -05:00
Steffen Klassert d50051407f ipv6: Allow sending packets through tunnels with wildcard endpoints
Currently we need the IP6_TNL_F_CAP_XMIT capabiltiy to transmit
packets through an ipv6 tunnel. This capability is set when the
tunnel gets configured, based on the tunnel endpoint addresses.

On tunnels with wildcard tunnel endpoints, we need to do the
capabiltiy checking on a per packet basis like it is done in
the receive path.

This patch extends ip6_tnl_xmit_ctl() to take local and remote
addresses as parameters to allow for per packet capabiltiy
checking.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-06 14:19:19 -05:00
Steffen Klassert f03eb128e3 gre6: Move the setting of dev->iflink into the ndo_init functions.
Otherwise it gets overwritten by register_netdev().

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-03 15:42:24 -05:00
David S. Miller 64b1f00a08 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-10-08 16:22:22 -04:00
Eric Dumazet 0287587884 net: better IFF_XMIT_DST_RELEASE support
Testing xmit_more support with netperf and connected UDP sockets,
I found strange dst refcount false sharing.

Current handling of IFF_XMIT_DST_RELEASE is not optimal.

Dropping dst in validate_xmit_skb() is certainly too late in case
packet was queued by cpu X but dequeued by cpu Y

The logical point to take care of drop/force is in __dev_queue_xmit()
before even taking qdisc lock.

As Julian Anastasov pointed out, need for skb_dst() might come from some
packet schedulers or classifiers.

This patch adds new helper to cleanly express needs of various drivers
or qdiscs/classifiers.

Drivers that need skb_dst() in their ndo_start_xmit() should call
following helper in their setup instead of the prior :

	dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
->
	netif_keep_dst(dev);

Instead of using a single bit, we use two bits, one being
eventually rebuilt in bonding/team drivers.

The other one, is permanent and blocks IFF_XMIT_DST_RELEASE being
rebuilt in bonding/team. Eventually, we could add something
smarter later.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-07 13:22:11 -04:00