Commit Graph

282 Commits

Author SHA1 Message Date
Eric Dumazet
567e4b7973 net: rfs: add hash collision detection
Receive Flow Steering is a nice solution but suffers from
hash collisions when a mix of connected and unconnected traffic
is received on the host, when flow hash table is populated.

Also, clearing flow in inet_release() makes RFS not very good
for short lived flows, as many packets can follow close().
(FIN , ACK packets, ...)

This patch extends the information stored into global hash table
to not only include cpu number, but upper part of the hash value.

I use a 32bit value, and dynamically split it in two parts.

For host with less than 64 possible cpus, this gives 6 bits for the
cpu number, and 26 (32-6) bits for the upper part of the hash.

Since hash bucket selection use low order bits of the hash, we have
a full hash match, if /proc/sys/net/core/rps_sock_flow_entries is big
enough.

If the hash found in flow table does not match, we fallback to RPS (if
it is enabled for the rxqueue).

This means that a packet for an non connected flow can avoid the
IPI through a unrelated/victim CPU.

This also means we no longer have to clear the table at socket
close time, and this helps short lived flows performance.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-08 16:53:57 -08:00
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
Takashi Iwai
c4d33e24b6 tun: Use static attribute groups for sysfs entries
Instead of manual calls of device_create_file() and
device_remove_files(), assign the static attribute groups to netdev
groups array.  This simplifies the code and avoids the possible
races.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05 00:30:47 -08:00
Vlad Yasevich
e3e3c423f8 Revert "drivers/net: Disable UFO through virtio"
This reverts commit 3d0ad09412.

Now that GSO functionality can correctly track if the fragment
id has been selected and select a fragment id if necessary,
we can re-enable UFO on tap/macvap and virtio devices.

Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-03 23:06:43 -08:00
Vlad Yasevich
72f6510745 Revert "drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packets"
This reverts commit 5188cd44c5.

Now that GSO layer can track if fragment id has been selected
and can allocate one if necessary, we don't need to do this in
tap and macvtap.  This reverts most of the code and only keeps
the new ipv6 fragment id generation function that is still needed.

Fixes: 3d0ad09412 (drivers/net: Disable UFO through virtio)
Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-03 23:06:43 -08:00
Jiri Pirko
df8a39defa net: rename vlan_tx_* helpers since "tx" is misleading there
The same macros are used for rx as well. So rename it.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-13 17:51:08 -05:00
Pankaj Gupta
baf71c5c1f tuntap: Increase the number of queues in tun.
Networking under kvm works best if we allocate a per-vCPU RX and TX
queue in a virtual NIC. This requires a per-vCPU queue on the host side.

It is now safe to increase the maximum number of queues.
Preceding patch: 'net: allow large number of rx queues'
made sure this won't cause failures due to high order memory
allocations. Increase it to 256: this is the max number of vCPUs
KVM supports.

Size of tun_struct changes from 8512 to 10496 after this patch. This keeps
pages allocated for tun_struct before and after the patch to 3.

Signed-off-by: Pankaj Gupta <pagupta@redhat.com>
Reviewed-by: David Gibson <dgibson@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 17:05:05 -05:00
Alex Gartrell
957f094f22 tun: return proper error code from tun_do_read
Instead of -1 with EAGAIN, read on a O_NONBLOCK tun fd will return 0.  This
fixes this by properly returning the error code from __skb_recv_datagram.

Signed-off-by: Alex Gartrell <agartrell@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31 14:14:54 -05:00
Alex Gartrell
87897931c8 tun: Fixed unsigned/signed comparison
Validated that this was actually using the unsigned comparison with gdb.

Signed-off-by: Alex Gartrell <agartrell@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31 14:14:54 -05:00
Michael S. Tsirkin
1cf8e410b6 tun: drop broken IFF_VNET_LE
Use TUNSETVNETLE/TUNGETVNETLE instead.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-16 11:19:41 -05:00
Linus Torvalds
70e71ca0af Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) New offloading infrastructure and example 'rocker' driver for
    offloading of switching and routing to hardware.

    This work was done by a large group of dedicated individuals, not
    limited to: Scott Feldman, Jiri Pirko, Thomas Graf, John Fastabend,
    Jamal Hadi Salim, Andy Gospodarek, Florian Fainelli, Roopa Prabhu

 2) Start making the networking operate on IOV iterators instead of
    modifying iov objects in-situ during transfers.  Thanks to Al Viro
    and Herbert Xu.

 3) A set of new netlink interfaces for the TIPC stack, from Richard
    Alpe.

 4) Remove unnecessary looping during ipv6 routing lookups, from Martin
    KaFai Lau.

 5) Add PAUSE frame generation support to gianfar driver, from Matei
    Pavaluca.

 6) Allow for larger reordering levels in TCP, which are easily
    achievable in the real world right now, from Eric Dumazet.

 7) Add a variable of napi_schedule that doesn't need to disable cpu
    interrupts, from Eric Dumazet.

 8) Use a doubly linked list to optimize neigh_parms_release(), from
    Nicolas Dichtel.

 9) Various enhancements to the kernel BPF verifier, and allow eBPF
    programs to actually be attached to sockets.  From Alexei
    Starovoitov.

10) Support TSO/LSO in sunvnet driver, from David L Stevens.

11) Allow controlling ECN usage via routing metrics, from Florian
    Westphal.

12) Remote checksum offload, from Tom Herbert.

13) Add split-header receive, BQL, and xmit_more support to amd-xgbe
    driver, from Thomas Lendacky.

14) Add MPLS support to openvswitch, from Simon Horman.

15) Support wildcard tunnel endpoints in ipv6 tunnels, from Steffen
    Klassert.

16) Do gro flushes on a per-device basis using a timer, from Eric
    Dumazet.  This tries to resolve the conflicting goals between the
    desired handling of bulk vs.  RPC-like traffic.

17) Allow userspace to ask for the CPU upon what a packet was
    received/steered, via SO_INCOMING_CPU.  From Eric Dumazet.

18) Limit GSO packets to half the current congestion window, from Eric
    Dumazet.

19) Add a generic helper so that all drivers set their RSS keys in a
    consistent way, from Eric Dumazet.

20) Add xmit_more support to enic driver, from Govindarajulu
    Varadarajan.

21) Add VLAN packet scheduler action, from Jiri Pirko.

22) Support configurable RSS hash functions via ethtool, from Eyal
    Perry.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1820 commits)
  Fix race condition between vxlan_sock_add and vxlan_sock_release
  net/macb: fix compilation warning for print_hex_dump() called with skb->mac_header
  net/mlx4: Add support for A0 steering
  net/mlx4: Refactor QUERY_PORT
  net/mlx4_core: Add explicit error message when rule doesn't meet configuration
  net/mlx4: Add A0 hybrid steering
  net/mlx4: Add mlx4_bitmap zone allocator
  net/mlx4: Add a check if there are too many reserved QPs
  net/mlx4: Change QP allocation scheme
  net/mlx4_core: Use tasklet for user-space CQ completion events
  net/mlx4_core: Mask out host side virtualization features for guests
  net/mlx4_en: Set csum level for encapsulated packets
  be2net: Export tunnel offloads only when a VxLAN tunnel is created
  gianfar: Fix dma check map error when DMA_API_DEBUG is enabled
  cxgb4/csiostor: Don't use MASTER_MUST for fw_hello call
  net: fec: only enable mdio interrupt before phy device link up
  net: fec: clear all interrupt events to support i.MX6SX
  net: fec: reset fep link status in suspend function
  net: sock: fix access via invalid file descriptor
  net: introduce helper macro for_each_cmsghdr
  ...
2014-12-11 14:27:06 -08:00
Linus Torvalds
6b9e2cea42 virtio: virtio 1.0 support, misc patches
This adds a lot of infrastructure for virtio 1.0 support.
 Notable missing pieces: virtio pci, virtio balloon (needs spec extension),
 vhost scsi.
 
 Plus, there are some minor fixes in a couple of places.
 
 Cc: David Miller <davem@davemloft.net>
 Cc: Rusty Russell <rusty@rustcorp.com.au>
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio updates from Michael Tsirkin:
 "virtio: virtio 1.0 support, misc patches

  This adds a lot of infrastructure for virtio 1.0 support.  Notable
  missing pieces: virtio pci, virtio balloon (needs spec extension),
  vhost scsi.

  Plus, there are some minor fixes in a couple of places.

  Note: some net drivers are affected by these patches.  David said he's
  fine with merging these patches through my tree.

  Rusty's on vacation, he acked using my tree for these, too"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (70 commits)
  virtio_ccw: finalize_features error handling
  virtio_ccw: future-proof finalize_features
  virtio_pci: rename virtio_pci -> virtio_pci_common
  virtio_pci: update file descriptions and copyright
  virtio_pci: split out legacy device support
  virtio_pci: setup config vector indirectly
  virtio_pci: setup vqs indirectly
  virtio_pci: delete vqs indirectly
  virtio_pci: use priv for vq notification
  virtio_pci: free up vq->priv
  virtio_pci: fix coding style for structs
  virtio_pci: add isr field
  virtio: drop legacy_only driver flag
  virtio_balloon: drop legacy_only driver flag
  virtio_ccw: rev 1 devices set VIRTIO_F_VERSION_1
  virtio: allow finalize_features to fail
  virtio_ccw: legacy: don't negotiate rev 1/features
  virtio: add API to detect legacy devices
  virtio_console: fix sparse warnings
  vhost: remove unnecessary forward declarations in vhost.h
  ...
2014-12-11 12:20:31 -08:00
Al Viro
c0371da604 put iov_iter into msghdr
Note that the code _using_ ->msg_iter at that point will be very
unhappy with anything other than unshifted iovec-backed iov_iter.
We still need to convert users to proper primitives.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-09 16:29:03 -05:00
Michael S. Tsirkin
56f0dcc5aa tun: TUN_VNET_LE support, fix sparse warnings for virtio headers
Pretty straight-forward: convert all fields to/from
virtio endian-ness.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Jason Wang <jasowang@redhat.com>
2014-12-09 12:05:31 +02:00
Michael S. Tsirkin
40630b82c2 tun: drop most type defines
It's just as easy to use IFF_ flags directly,
there's no point in adding our own defines.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:05:30 +02:00
Michael S. Tsirkin
031f5e0338 tun: move internal flag defines out of uapi
TUN_ flags are internal and never exposed
to userspace. Any application using it is almost
certainly buggy.

Move them out to tun.c.

Note: we remove these completely in follow-up patches,
this code movement is split out for ease of review.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2014-12-09 12:05:30 +02:00
Al Viro
ba00410b81 Merge branch 'iov_iter' into for-next 2014-12-08 20:39:29 -05:00
Jason Wang
f51a5e82ea tun/macvtap: use consume_skb() instead of kfree_skb() when needed
To be more friendly with drop monitor, we should only call kfree_skb() when
the packets were dropped and use consume_skb() in other cases.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-05 21:45:09 -08:00
Herbert Xu
d8febb77b5 tun: Fix GSO meta-data handling in tun_get_user
When we write the GSO meta-data in tun_get_user we end up advancing
the IO vector twice, thus exhausting the user buffer before we can
finish writing the packet.

Fixes: f5ff53b4d9 ("{macvtap,tun}_get_user(): switch to iov_iter")
Reported-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-02 20:53:47 -08:00
Al Viro
f5ff53b4d9 {macvtap,tun}_get_user(): switch to iov_iter
allows to switch macvtap and tun from ->aio_write() to ->write_iter()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-24 05:15:41 -05:00
Al Viro
9b067034d0 switch drivers/net/tun.c to ->read_iter()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-24 04:28:51 -05:00
Jason Wang
baeababb5b tun: return NET_XMIT_DROP for dropped packets
After commit 5d09710925
("tun: only queue packets on device"), NETDEV_TX_OK was returned for
dropped packets. This will confuse pktgen since dropped packets were
counted as sent ones.

Fixing this by returning NET_XMIT_DROP to let pktgen count it as error
packet.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-19 14:43:47 -05:00
Jason Wang
8c847d2541 tun: fix issues of iovec iterators using in tun_put_user()
This patch fixes two issues after using iovec iterators:
- vlan_offset should be initialized to zero, otherwise unexpected offset
  will be used in skb_copy_datagram_iter()
- advance iovec iterator when vnet_hdr_sz is greater than sizeof(gso), this
  is the case when mergeable rx buffer were enabled for a virt guest.

Fixes e0b46d0ee9 ("tun: Use iovec iterators")
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-13 14:33:22 -05:00
Herbert Xu
e0b46d0ee9 tun: Use iovec iterators
This patch removes the use of skb_copy_datagram_const_iovec in
favour of the iovec iterator-based skb_copy_datagram_iter.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-07 12:13:34 -05:00
Joe Perches
a3816ab0e8 fs: Convert show_fdinfo functions to void
seq_printf functions shouldn't really check the return value.
Checking seq_has_overflowed() occasionally is used instead.

Update vfs documentation.

Link: http://lkml.kernel.org/p/e37e6e7b76acbdcc3bb4ab2a57c8f8ca1ae11b9a.1412031505.git.joe@perches.com

Cc: David S. Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Joe Perches <joe@perches.com>
[ did a few clean ups ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-11-05 14:13:23 -05:00
Herbert Xu
2eb783c43e tun: Fix TUN_PKT_STRIP setting
We set the flag TUN_PKT_STRIP if the user buffer provided is too
small to contain the entire packet plus meta-data.  However, this
has been broken ever since we added GSO meta-data.  VLAN acceleration
also has the same problem.

This patch fixes this by taking both into account when setting the
TUN_PKT_STRIP flag.

The fact that this has been broken for six years without anyone
realising means that nobody actually uses this flag.

Fixes: f43798c276 ("tun: Allow GSO using virtio_net_hdr")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-03 14:27:06 -05:00
Herbert Xu
a8f9bfdf98 tun: Fix csum_start with VLAN acceleration
When VLAN acceleration is in use on the xmit path, we end up
setting csum_start to the wrong place.  The result is that the
whoever ends up doing the checksum setting will corrupt the packet
instead of writing the checksum to the expected location, usually
this means writing the checksum with an offset of -4.

This patch fixes this by adjusting csum_start when VLAN acceleration
is detected.

Fixes: 6680ec68ef ("tuntap: hardware vlan tx support")
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-03 14:27:06 -05:00
Ben Hutchings
5188cd44c5 drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packets
UFO is now disabled on all drivers that work with virtio net headers,
but userland may try to send UFO/IPv6 packets anyway.  Instead of
sending with ID=0, we should select identifiers on their behalf (as we
used to).

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 916e4cf46d ("ipv6: reuse ip6_frag_id from ip6_ufo_append_data")
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-30 20:01:18 -04:00
Ben Hutchings
3d0ad09412 drivers/net: Disable UFO through virtio
IPv6 does not allow fragmentation by routers, so there is no
fragmentation ID in the fixed header.  UFO for IPv6 requires the ID to
be passed separately, but there is no provision for this in the virtio
net protocol.

Until recently our software implementation of UFO/IPv6 generated a new
ID, but this was a bug.  Now we will use ID=0 for any UFO/IPv6 packet
passed through a tap, which is even worse.

Unfortunately there is no distinction between UFO/IPv4 and v6
features, so disable UFO on taps and virtio_net completely until we
have a proper solution.

We cannot depend on VM managers respecting the tap feature flags, so
keep accepting UFO packets but log a warning the first time we do
this.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 916e4cf46d ("ipv6: reuse ip6_frag_id from ip6_ufo_append_data")
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-30 20:01:18 -04:00
Jeff Layton
e0b93eddfe security: make security_file_set_fowner, f_setown and __f_setown void return
security_file_set_fowner always returns 0, so make it f_setown and
__f_setown void return functions and fix up the error handling in the
callers.

Cc: linux-security-module@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2014-09-09 16:01:36 -04:00
Tom Gundersen
c835a67733 net: set name_assign_type in alloc_netdev()
Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert
all users to pass NET_NAME_UNKNOWN.

Coccinelle patch:

@@
expression sizeof_priv, name, setup, txqs, rxqs, count;
@@

(
-alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs)
+alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs)
|
-alloc_netdev_mq(sizeof_priv, name, setup, count)
+alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count)
|
-alloc_netdev(sizeof_priv, name, setup)
+alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup)
)

v9: move comments here from the wrong commit

Signed-off-by: Tom Gundersen <teg@jklm.no>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-15 16:12:48 -07:00
Xi Wang
9e641bdcfa net-tun: restructure tun_do_read for better sleep/wakeup efficiency
tun_do_read always adds current thread to wait queue, even if a packet
is ready to read. This is inefficient because both sleeper and waker
want to acquire the wait queue spin lock when packet rate is high.

We restructure the read function and use common kernel networking
routines to handle receive, sleep and wakeup. With the change
available packets are checked first before the reading thread is added
to the wait queue.

Ran performance tests with the following configuration:

 - my packet generator -> tap1 -> br0 -> tap0 -> my packet consumer
 - sender pinned to one core and receiver pinned to another core
 - sender send small UDP packets (64 bytes total) as fast as it can
 - sandy bridge cores
 - throughput are receiver side goodput numbers

The results are

baseline: 731k pkts/sec, cpu utilization at 1.50 cpus
 changed: 783k pkts/sec, cpu utilization at 1.53 cpus

The performance difference is largely determined by packet rate and
inter-cpu communication cost. For example, if the sender and
receiver are pinned to different cpu sockets, the results are

baseline: 558k pkts/sec, cpu utilization at 1.71 cpus
 changed: 690k pkts/sec, cpu utilization at 1.67 cpus

Co-authored-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Xi Wang <xii@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-21 15:50:28 -04:00
Monam Agarwal
c956674b7c drivers/net: Use RCU_INIT_POINTER(x, NULL) in tun.c
This patch replaces rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL)

The rcu_assign_pointer() ensures that the initialization of a structure
is carried out before storing a pointer to that structure.
And in the case of the NULL pointer, there is no structure to initialize.
So, rcu_assign_pointer(p, NULL) can be safely converted to RCU_INIT_POINTER(p, NULL)

Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-27 00:18:09 -04:00
Fernando Luis Vazquez Cao
6671b2240c tun: remove bogus hardware vlan acceleration flags from vlan_features
Even though only the outer vlan tag can be HW accelerated in the transmission
path, in the TUN/TAP driver vlan_features mirrors hw_features, which happens
to have the NETIF_F_HW_VLAN_?TAG_TX flags set. Because of this, during packet
tranmisssion through a stacked vlan device dev_hard_start_xmit, (incorrectly)
assuming that the vlan device supports hardware vlan acceleration, does not
add the vlan header to the skb payload and the inner vlan tags are lost
(vlan_tci contains the outer vlan tag when userspace reads the packet from
the tap device).

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-20 02:15:38 -05:00
Daniel Borkmann
99932d4fc0 netdevice: add queue selection fallback handler for ndo_select_queue
Add a new argument for ndo_select_queue() callback that passes a
fallback handler. This gets invoked through netdev_pick_tx();
fallback handler is currently __netdev_pick_tx() as most drivers
invoke this function within their customized implementation in
case for skbs that don't need any special handling. This fallback
handler can then be replaced on other call-sites with different
queue selection methods (e.g. in packet sockets, pktgen etc).

This also has the nice side-effect that __netdev_pick_tx() is
then only invoked from netdev_pick_tx() and export of that
function to modules can be undone.

Suggested-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-17 00:36:34 -05:00
Masatake YAMATO
93e14b6d77 tun: add device name(iff) field to proc fdinfo entry
A file descriptor opened for /dev/net/tun and a tun device are
connected with ioctl.  Though understanding the connection is
important for trouble shooting, no way is given to a user to know
the connected device for a given file descriptor at userland.

This patch adds a new fdinfo field for the device name connected to
a file descriptor opened for /dev/net/tun.

Here is an example of the field:

    # lsof | grep tun
    qemu-syst 4565         qemu   25u      CHR             10,200       0t138      12921 /dev/net/tun
    ...

    # cat /proc/4565/fdinfo/25
    pos:	138
    flags:	0104002
    iff:	vnet0

    # ip link show dev vnet0
    8: vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 ...

changelog:

    v2: indent iff just like the other fdinfo fields are.
    v3: remove unused variable.
        Both are suggested by David Miller <davem@davemloft.net>.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-28 23:46:56 -08:00
Dominic Curran
fa35864e0b tuntap: Fix for a race in accessing numqueues
A patch for fixing a race between queue selection and changing queues
was introduced in commit 92bb73ea2("tuntap: fix a possible race between
queue selection and changing queues").

The fix was to prevent the driver from re-reading the tun->numqueues
more than once within tun_select_queue() using ACCESS_ONCE().

We have been experiancing 'Divide-by-zero' errors in tun_net_xmit()
since we moved from 3.6 to 3.10, and believe that they come from a
simular source where the value of tun->numqueues changes to zero
between the first and a subsequent read of tun->numqueues.

The fix is a simular use of ACCESS_ONCE(), as well as a multiply
instead of a divide in the if statement.

Signed-off-by: Dominic Curran <dominic.curran@citrix.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Maxim Krasnyansky <maxk@qti.qualcomm.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Max Krasnyansky <maxk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 21:32:56 -08:00
David S. Miller
0a379e21c5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-01-14 14:42:42 -08:00
Jason Wang
f663dd9aaf net: core: explicitly select a txq before doing l2 forwarding
Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The
will cause several issues:

- NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan
  instead of lower device which misses the necessary txq synchronization for
  lower device such as txq stopping or frozen required by dev watchdog or
  control path.
- dev_hard_start_xmit() was called with NULL txq which bypasses the net device
  watchdog.
- dev_hard_start_xmit() does not check txq everywhere which will lead a crash
  when tso is disabled for lower device.

Fix this by explicitly introducing a new param for .ndo_select_queue() for just
selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also
extended to accept this parameter and dev_queue_xmit_accel() was used to do l2
forwarding transmission.

With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need
to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep
a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of
dev_queue_xmit() to do the transmission.

In the future, it was also required for macvtap l2 forwarding support since it
provides a necessary synchronization method.

Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: e1000-devel@lists.sourceforge.net
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-10 13:23:08 -05:00
Zhi Yong Wu
fbe4d4565b tun, rfs: fix the incorrect hash value
The code incorrectly save the queue index as the hash, so this patch
is fixing it with the hash received in the stack receive path.

Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-02 02:41:22 -05:00
Tom Herbert
9bc8893937 tun: Add support for RFS on tun flows
This patch adds support so that the rps_flow_tables (RFS) can be
programmed using the tun flows which are already set up to track flows
for the purposes of queue selection.

On the receive path (corresponding to select_queue and tun_net_xmit) the
rxhash is saved in the flow_entry.  The original code only does flow
lookup in select_queue, so this patch adds a flow lookup in tun_net_xmit
if num_queues == 1 (select_queue is not called from
dev_queue_xmit->netdev_pick_tx in that case).

The flow is recorded (processing CPU) in tun_flow_update (TX path), and
reset when flow is deleted.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-31 13:31:34 -05:00
David S. Miller
143c905494 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/intel/i40e/i40e_main.c
	drivers/net/macvtap.c

Both minor merge hassles, simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-18 16:42:06 -05:00
Tom Herbert
3958afa1b2 net: Change skb_get_rxhash to skb_get_hash
Changing name of function as part of making the hash in skbuff to be
generic property, not just for receive path.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-17 16:36:21 -05:00
Jason Wang
e6fd07c899 tun: unbreak truncated packet signalling
Commit 6680ec68ef
(tuntap: hardware vlan tx support) breaks the truncated packet signal by nev
return a length greater than iov length in tun_put_user(). This patch fixes
by always return the length of packet plus possible vlan header. Caller can
detect the truncated packet by comparing the return value and the size of io
length.

Cc: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-11 15:23:06 -05:00
David S. Miller
bbd37626e6 net: Revert macvtap/tun truncation signalling changes.
Jason Wang and Michael S. Tsirkin are still discussing how
to properly fix this.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10 22:10:21 -05:00
Jason Wang
923347bb83 tun: unbreak truncated packet signalling
Commit 6680ec68ef
(tuntap: hardware vlan tx support) breaks the truncated packet signal by never
return a length greater than iov length in tun_put_user(). This patch fixes this
by always return the length of packet plus possible vlan header. Caller can
detect the truncated packet by comparing the return value and the size of iov
length.

Reported-by: Vlad Yasevich <vyasevich@gmail.com>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10 22:06:49 -05:00
David S. Miller
42404c0915 Revert "tun: remove useless codes in tun_chr_aio_read() and tun_recvmsg()"
This reverts commit 73713357ab.

MSG_TRUNC handling was broken and is going to be fixed in
the 'net' tree, so revert this.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10 22:05:45 -05:00
Zhi Yong Wu
73713357ab tun: remove useless codes in tun_chr_aio_read() and tun_recvmsg()
By checking related codes, it is impossible that ret > len or total_len,
so we should remove some useless codes in both above functions.

Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09 20:36:08 -05:00
David S. Miller
34f9f43710 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merge 'net' into 'net-next' to get the AF_PACKET bug fix that
Daniel's direct transmit changes depend upon.

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-09 20:20:14 -05:00
Zhi Yong Wu
f96eb74c84 tun: remove unused parameter in tun_do_read()
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06 15:22:05 -05:00