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path: root/drivers/net/tun.c
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2015-07-03Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio/vhost cross endian support from Michael Tsirkin: "I have just queued some more bugfix patches today but none fix regressions and none are related to these ones, so it looks like a good time for a merge for -rc1. The motivation for this is support for legacy BE guests on the new LE hosts. There are two redeeming properties that made me merge this: - It's a trivial amount of code: since we wrap host/guest accesses anyway, almost all of it is well hidden from drivers. - Sane platforms would never set flags like VHOST_CROSS_ENDIAN_LEGACY, and when it's clear, there's zero overhead (as some point it was tested by compiling with and without the patches, got the same stripped binary). Maybe we could create a Kconfig symbol to enforce the second point: prevent people from enabling it eg on x86. I will look into this" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: virtio-pci: alloc only resources actually used. macvtap/tun: cross-endian support for little-endian hosts vhost: cross-endian support for legacy devices virtio: add explicit big-endian support to memory accessors vhost: introduce vhost_is_little_endian() helper vringh: introduce vringh_is_little_endian() helper macvtap: introduce macvtap_is_little_endian() helper tun: add tun_is_little_endian() helper virtio: introduce virtio_is_little_endian() helper
2015-06-01macvtap/tun: cross-endian support for little-endian hostsGreg Kurz
The VNET_LE flag was introduced to fix accesses to virtio 1.0 headers that are always little-endian. It can also be used to handle the special case of a legacy little-endian device implemented by a big-endian host. Let's add a flag and ioctls for big-endian devices as well. If both flags are set, little-endian wins. Since this is isn't a common usecase, the feature is controlled by a kernel config option (not set by default). Both macvtap and tun are covered by this patch since they share the same API with userland. Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2015-06-01virtio: add explicit big-endian support to memory accessorsGreg Kurz
The current memory accessors logic is: - little endian if little_endian - native endian (i.e. no byteswap) if !little_endian If we want to fully support cross-endian vhost, we also need to be able to convert to big endian. Instead of changing the little_endian argument to some 3-value enum, this patch changes the logic to: - little endian if little_endian - big endian if !little_endian The native endian case is handled by all users with a trivial helper. This patch doesn't change any functionality, nor it does add overhead. Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2015-06-01tun: add tun_is_little_endian() helperGreg Kurz
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
2015-05-11net: Pass kern from net_proto_family.create to sk_allocEric W. Biederman
In preparation for changing how struct net is refcounted on kernel sockets pass the knowledge that we are creating a kernel socket from sock_create_kern through to sk_alloc. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11tun: Utilize the normal socket network namespace refcounting.Eric W. Biederman
There is no need for tun to do the weird network namespace refcounting. The existing network namespace refcounting in tfile has almost exactly the same lifetime. So rewrite the code to use the struct sock network namespace refcounting and remove the unnecessary hand rolled network namespace refcounting and the unncesary tfile->net. This change allows the tun code to directly call sock_put bypassing sock_release and making SOCK_EXTERNALLY_ALLOCATED unnecessary. Remove the now unncessary tun_release so that if anything tries to use the sock_release code path the kernel will oops, and let us know about the bug. The macvtap code already uses it's internal socket this way. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-11make new_sync_{read,write}() staticAl Viro
All places outside of core VFS that checked ->read and ->write for being NULL or called the methods directly are gone now, so NULL {read,write} with non-NULL {read,write}_iter will do the right thing in all cases. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-02net: Remove iocb argument from sendmsg and recvmsgYing Xue
After TIPC doesn't depend on iocb argument in its internal implementations of sendmsg() and recvmsg() hooks defined in proto structure, no any user is using iocb argument in them at all now. Then we can drop the redundant iocb argument completely from kinds of implementations of both sendmsg() and recvmsg() in the entire networking stack. Cc: Christoph Hellwig <hch@lst.de> Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-08net: rfs: add hash collision detectionEric Dumazet
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>
2015-02-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
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>
2015-02-05tun: Use static attribute groups for sysfs entriesTakashi Iwai
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>
2015-02-03Revert "drivers/net: Disable UFO through virtio"Vlad Yasevich
This reverts commit 3d0ad09412ffe00c9afa201d01effdb6023d09b4. 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>
2015-02-03Revert "drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packets"Vlad Yasevich
This reverts commit 5188cd44c55db3e92cd9e77a40b5baa7ed4340f7. 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: 3d0ad09412ff (drivers/net: Disable UFO through virtio) Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-13net: rename vlan_tx_* helpers since "tx" is misleading thereJiri Pirko
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>
2015-01-12tuntap: Increase the number of queues in tun.Pankaj Gupta
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>
2014-12-31tun: return proper error code from tun_do_readAlex Gartrell
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>
2014-12-31tun: Fixed unsigned/signed comparisonAlex Gartrell
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>
2014-12-16tun: drop broken IFF_VNET_LEMichael S. Tsirkin
Use TUNSETVNETLE/TUNGETVNETLE instead. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-11Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds
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 ...
2014-12-11Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
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 ...
2014-12-09put iov_iter into msghdrAl Viro
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>
2014-12-09tun: TUN_VNET_LE support, fix sparse warnings for virtio headersMichael S. Tsirkin
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>
2014-12-09tun: drop most type definesMichael S. Tsirkin
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>
2014-12-09tun: move internal flag defines out of uapiMichael S. Tsirkin
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>
2014-12-08Merge branch 'iov_iter' into for-nextAl Viro
2014-12-05tun/macvtap: use consume_skb() instead of kfree_skb() when neededJason Wang
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>
2014-12-02tun: Fix GSO meta-data handling in tun_get_userHerbert Xu
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: f5ff53b4d97c ("{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>
2014-11-24{macvtap,tun}_get_user(): switch to iov_iterAl Viro
allows to switch macvtap and tun from ->aio_write() to ->write_iter() Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-24switch drivers/net/tun.c to ->read_iter()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-19tun: return NET_XMIT_DROP for dropped packetsJason Wang
After commit 5d097109257c03a71845729f8db6b5770c4bbedc ("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>
2014-11-13tun: fix issues of iovec iterators using in tun_put_user()Jason Wang
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 e0b46d0ee9c240c7430a47e9b0365674d4a04522 ("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>
2014-11-07tun: Use iovec iteratorsHerbert Xu
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>
2014-11-05fs: Convert show_fdinfo functions to voidJoe Perches
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>
2014-11-03tun: Fix TUN_PKT_STRIP settingHerbert Xu
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: f43798c27684 ("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>
2014-11-03tun: Fix csum_start with VLAN accelerationHerbert Xu
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: 6680ec68eff4 ("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>
2014-10-30drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packetsBen Hutchings
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: 916e4cf46d02 ("ipv6: reuse ip6_frag_id from ip6_ufo_append_data") Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-30drivers/net: Disable UFO through virtioBen Hutchings
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: 916e4cf46d02 ("ipv6: reuse ip6_frag_id from ip6_ufo_append_data") Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-09security: make security_file_set_fowner, f_setown and __f_setown void returnJeff Layton
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>
2014-07-15net: set name_assign_type in alloc_netdev()Tom Gundersen
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>
2014-05-21net-tun: restructure tun_do_read for better sleep/wakeup efficiencyXi Wang
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>
2014-03-27drivers/net: Use RCU_INIT_POINTER(x, NULL) in tun.cMonam Agarwal
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>
2014-02-20tun: remove bogus hardware vlan acceleration flags from vlan_featuresFernando Luis Vazquez Cao
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>
2014-02-17netdevice: add queue selection fallback handler for ndo_select_queueDaniel Borkmann
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>
2014-01-28tun: add device name(iff) field to proc fdinfo entryMasatake YAMATO
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>
2014-01-22tuntap: Fix for a race in accessing numqueuesDominic Curran
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>
2014-01-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2014-01-10net: core: explicitly select a txq before doing l2 forwardingJason Wang
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>
2014-01-02tun, rfs: fix the incorrect hash valueZhi Yong Wu
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>
2013-12-31tun: Add support for RFS on tun flowsTom Herbert
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>
2013-12-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
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>