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path: root/drivers/net/tun.c
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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>
2013-12-17net: Change skb_get_rxhash to skb_get_hashTom Herbert
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>
2013-12-11tun: unbreak truncated packet signallingJason Wang
Commit 6680ec68eff47d36f67b4351bc9836fd6cba9532 (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>
2013-12-10net: Revert macvtap/tun truncation signalling changes.David S. Miller
Jason Wang and Michael S. Tsirkin are still discussing how to properly fix this. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-10tun: unbreak truncated packet signallingJason Wang
Commit 6680ec68eff47d36f67b4351bc9836fd6cba9532 (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>
2013-12-10Revert "tun: remove useless codes in tun_chr_aio_read() and tun_recvmsg()"David S. Miller
This reverts commit 73713357ab58aacda1af715bb5a623528dbbfd79. 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>
2013-12-09tun: remove useless codes in tun_chr_aio_read() and tun_recvmsg()Zhi Yong Wu
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>
2013-12-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
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>
2013-12-06tun: remove unused parameter in tun_do_read()Zhi Yong Wu
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06tun: spelling fixesstephen hemminger
Fix spelling errors in tun driver. Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-12-06tun: update file current positionZhi Yong Wu
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-14tuntap: limit head length of skb allocatedJason Wang
We currently use hdr_len as a hint of head length which is advertised by guest. But when guest advertise a very big value, it can lead to an 64K+ allocating of kmalloc() which has a very high possibility of failure when host memory is fragmented or under heavy stress. The huge hdr_len also reduce the effect of zerocopy or even disable if a gso skb is linearized in guest. To solves those issues, this patch introduces an upper limit (PAGE_SIZE) of the head, which guarantees an order 0 allocation each time. Cc: Stefan Hajnoczi <stefanha@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-10-08tun: don't look at current when non-blockingMichael S. Tsirkin
We play with a wait queue even if socket is non blocking. This is an obvious waste. Besides, it will prevent calling the non blocking variant when current is not valid. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-12tuntap: correctly handle error in tun_set_iff()Jason Wang
Commit c8d68e6be1c3b242f1c598595830890b65cea64a (tuntap: multiqueue support) only call free_netdev() on error in tun_set_iff(). This causes several issues: - memory of tun security were leaked - use after free since the flow gc timer was not deleted and the tfile were not detached This patch solves the above issues. Reported-by: Wannes Rombouts <wannes.rombouts@epitech.eu> Cc: Michael S. Tsirkin <mst@redhat.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>
2013-09-05tuntap: orphan frags before trying to set tx timestampJason Wang
sock_tx_timestamp() will clear all zerocopy flags of skb which may lead the frags never to be orphaned. This will break guest to guest traffic when zerocopy is enabled. Fix this by orphaning the frags before trying to set tx time stamp. The issue were introduced by commit eda297729171fe16bf34fe5b0419dfb69060f623 (tun: Support software transmit time stamping). Cc: Richard Cochran <richardcochran@gmail.com> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Acked-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-09-05tuntap: purge socket error queue on detachJason Wang
Commit eda297729171fe16bf34fe5b0419dfb69060f623 (tun: Support software transmit time stamping) will queue skbs into error queue when tx stamping is enabled. But it forgets to purge the error queue during detach. This patch fixes this. Cc: Richard Cochran <richardcochran@gmail.com> Acked-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-21tun: Get skfilter layoutPavel Emelyanov
The only thing we may have from tun device is the fprog, whic contains the number of filter elements and a pointer to (user-space) memory where the elements are. The program itself may not be available if the device is persistent and detached. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-21tun: Allow to skip filter on attachPavel Emelyanov
There's a small problem with sk-filters on tun devices. Consider an application doing this sequence of steps: fd = open("/dev/net/tun"); ioctl(fd, TUNSETIFF, { .ifr_name = "tun0" }); ioctl(fd, TUNATTACHFILTER, &my_filter); ioctl(fd, TUNSETPERSIST, 1); close(fd); At that point the tun0 will remain in the system and will keep in mind that there should be a socket filter at address '&my_filter'. If after that we do fd = open("/dev/net/tun"); ioctl(fd, TUNSETIFF, { .ifr_name = "tun0" }); we most likely receive the -EFAULT error, since tun_attach() would try to connect the filter back. But (!) if we provide a filter at address &my_filter, then tun0 will be created and the "new" filter would be attached, but application may not know about that. This may create certain problems to anyone using tun-s, but it's critical problem for c/r -- if we meet a persistent tun device with a filter in mind, we will not be able to attach to it to dump its state (flags, owner, address, vnethdr size, etc.). The proposal is to allow to attach to tun device (with TUNSETIFF) w/o attaching the filter to the tun-file's socket. After this attach app may e.g clean the device by dropping the filter, it doesn't want to have one, or (in case of c/r) get information about the device with tun ioctls. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-21tun: Report whether the queue is attached or notPavel Emelyanov
Multiqueue tun devices allow to attach and detach from its queues while keeping the interface itself set on file. Knowing this is critical for the checkpoint part of criu project. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-21tun: Add ability to create tun device with given indexPavel Emelyanov
Tun devices cannot be created with ifidex user wants, but it's required by checkpoint-restore project. Long time ago such ability was implemented for rtnl_ops-based interface for creating links (9c7dafbf net: Allow to create links with given ifindex), but the only API for creating and managing tuntap devices is ioctl-based and is evolving with adding new ones (cde8b15f tuntap: add ioctl to attach or detach a file form tuntap device). Following that trend, here's how a new ioctl that sets the ifindex for device, that _will_ be created by TUNSETIFF ioctl looks like. So those who want a tuntap device with the ifindex N, should open the tun device, call ioctl(fd, TUNSETIFINDEX, &N), then call TUNSETIFF. If the index N is busy, then the register_netdev will find this out and the ioctl would be failed with -EBUSY. If setifindex is not called, then it will be generated as before. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2013-08-15tun: signedness bug in tun_get_user()Dan Carpenter
The recent fix d9bf5f1309 "tun: compare with 0 instead of total_len" is not totally correct. Because "len" and "sizeof()" are size_t type, that means they are never less than zero. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-13tun: compare with 0 instead of total_lenWeiping Pan
Since we set "len = total_len" in the beginning of tun_get_user(), so we should compare the new len with 0, instead of total_len, or the if statement always returns false. Signed-off-by: Weiping Pan <wpan@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-10net: attempt high order allocations in sock_alloc_send_pskb()Eric Dumazet
Adding paged frags skbs to af_unix sockets introduced a performance regression on large sends because of additional page allocations, even if each skb could carry at least 100% more payload than before. We can instruct sock_alloc_send_pskb() to attempt high order allocations. Most of the time, it does a single page allocation instead of 8. I added an additional parameter to sock_alloc_send_pskb() to let other users to opt-in for this new feature on followup patches. Tested: Before patch : $ netperf -t STREAM_STREAM STREAM STREAM TEST Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 2304 212992 212992 10.00 46861.15 After patch : $ netperf -t STREAM_STREAM STREAM STREAM TEST Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 2304 212992 212992 10.00 57981.11 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-07net: move zerocopy_sg_from_iovec() to net/core/datagram.cJason Wang
To let it be reused and reduce code duplication. Also document this function. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-07net: move iov_pages() to net/core/iovec.cJason Wang
To let it be reused and reduce code duplication. Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-27tuntap: hardware vlan tx supportJason Wang
Inspired by commit f09e2249c4f5c7c13261ec73f5a7807076af0c8e (macvtap: restore vlan header on user read). This patch adds hardware vlan tx support for tuntap. This is done by copying vlan header directly into userspace in tun_put_user() instead of doing it through __vlan_put_tag() in dev_hard_start_xmit(). This eliminates one unnecessary memmove() in vlan_insert_tag() for 802.1ad and 802.1q traffic. pktgen test shows about 20% improvement for 802.1q traffic: Before: 662149pps 317Mb/sec (317831520bps) errors: 0 After: 801033pps 384Mb/sec (384495840bps) errors: 0 Cc: Basil Gor <basil.gor@gmail.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-22tun: Support software transmit time stamping.Richard Cochran
This patch adds transmit time stamping to the tun/tap driver. Similar support already exists for UDP, can, and raw packets. Signed-off-by: Richard Cochran <richardcochran@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-18tuntap: do not zerocopy if iov needs more pages than MAX_SKB_FRAGSJason Wang
We try to linearize part of the skb when the number of iov is greater than MAX_SKB_FRAGS. This is not enough since each single vector may occupy more than one pages, so zerocopy_sg_fromiovec() may still fail and may break the guest network. Solve this problem by calculate the pages needed for iov before trying to do zerocopy and switch to use copy instead of zerocopy if it needs more than MAX_SKB_FRAGS. This is done through introducing a new helper to count the pages for iov, and call uarg->callback() manually when switching from zerocopy to copy to notify vhost. We can do further optimization on top. The bug were introduced from commit 0690899b4d4501b3505be069b9a687e68ccbe15b (tun: experimental zero copy tx support) Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-10tuntap: correctly linearize skb when zerocopy is usedJason Wang
Userspace may produce vectors greater than MAX_SKB_FRAGS. When we try to linearize parts of the skb to let the rest of iov to be fit in the frags, we need count copylen into linear when calling tun_alloc_skb() instead of partly counting it into data_len. Since this breaks zerocopy_sg_from_iovec() since its inner counter assumes nr_frags should be zero at beginning. This cause nr_frags to be increased wrongly without setting the correct frags. This bug were introduced from 0690899b4d4501b3505be069b9a687e68ccbe15b (tun: experimental zero copy tx support) Cc: Michael S. Tsirkin <mst@redhat.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>
2013-07-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/freescale/fec_main.c drivers/net/ethernet/renesas/sh_eth.c net/ipv4/gre.c The GRE conflict is between a bug fix (kfree_skb --> kfree_skb_list) and the splitting of the gre.c code into seperate files. The FEC conflict was two sets of changes adding ethtool support code in an "!CONFIG_M5272" CPP protected block. Finally the sh_eth.c conflict was between one commit add bits set in the .eesr_err_check mask whilst another commit removed the .tx_error_check member and assignments. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-25tun: fix recovery from gup errorsMichael S. Tsirkin
get user pages might fail partially in tun zero copy mode. To recover we need to put all pages that we got, but code used a wrong index resulting in double-free errors. Reported-by: Brad Hubbard <bhubbard@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/wireless/ath/ath9k/Kconfig drivers/net/xen-netback/netback.c net/batman-adv/bat_iv_ogm.c net/wireless/nl80211.c The ath9k Kconfig conflict was a change of a Kconfig option name right next to the deletion of another option. The xen-netback conflict was overlapping changes involving the handling of the notify list in xen_netbk_rx_action(). Batman conflict resolution provided by Antonio Quartulli, basically keep everything in both conflict hunks. The nl80211 conflict is a little more involved. In 'net' we added a dynamic memory allocation to nl80211_dump_wiphy() to fix a race that Linus reported. Meanwhile in 'net-next' the handlers were converted to use pre and post doit handlers which use a flag to determine whether to hold the RTNL mutex around the operation. However, the dump handlers to not use this logic. Instead they have to explicitly do the locking. There were apparent bugs in the conversion of nl80211_dump_wiphy() in that we were not dropping the RTNL mutex in all the return paths, and it seems we very much should be doing so. So I fixed that whilst handling the overlapping changes. To simplify the initial returns, I take the RTNL mutex after we try to allocate 'tb'. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-12tun: Turn tun_flow_init() into void fnPavel Emelyanov
This routine doesn't fail since 9fdc6bef (tuntap: dont use a private kmem_cache) so it makes sense to compact the code a little bit. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-12tun: Report "persist" flag to userspacePavel Emelyanov
The TUN_PERSIST flag is not reported at all -- both TUNGETIFF, and sysfs "flags" attribute skip one. Knowing whether a device is persistent or not is critical for checkpoint-restore, thus I propose to add the read-only IFF_PERSIST one for this. Setting this new IFF_PERSIST is hardly possible, as TUNSETIFF doesn't check for unknown flags being zero and thus there can be trash. Signed-off-by: Pavel Emelyanov <xemul@parallels.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-06-12tuntap: set SOCK_ZEROCOPY flag during openJason Wang
Commit 54f968d6efdbf7dec36faa44fc11f01b0e4d1990 (tuntap: move socket to tun_file) forgets to set SOCK_ZEROCOPY flag, which will prevent vhost_net from doing zercopy w/ tap. This patch fixes this by setting it during file open. Cc: Michael S. Tsirkin <mst@redhat.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>
2013-06-10tuntap: fix a possible race between queue selection and changing queuesJason Wang
Complier may generate codes that re-read the tun->numqueues during tun_select_queue(). This may be a race if vlan->numqueues were changed in the same time and can lead unexpected result (e.g. very huge value). We need prevent the compiler from generating such codes by adding an ACCESS_ONCE() to make sure tun->numqueues were only read once. Bug were introduced by commit c8d68e6be1c3b242f1c598595830890b65cea64a (tuntap: multiqueue support). Reported-by: Michael S. Tsirkin <mst@redhat.com> Cc: Michael S. Tsirkin <mst@redhat.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>
2013-05-29tuntap: forbid changing mq flag for persistent deviceJason Wang
We currently allow changing the mq flag (IFF_MULTI_QUEUE) for a persistent device. This will result a mismatch between the number the queues in netdev and tuntap. This is because we only allocate a 1q netdevice when IFF_MULTI_QUEUE was not specified, so when we set the IFF_MULTI_QUEUE and try to attach more queues later, netif_set_real_num_tx_queues() may fail which result a single queue netdevice with multiple sockets attached. Solve this by disallowing changing the mq flag for persistent device. Bug was introduced by commit edfb6a148ce62e5e19354a1dcd9a34e00815c2a1 (tuntap: reduce memory using of queues). Reported-by: Sriram Narasimhan <sriram.narasimhan@hp.com> Cc: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c drivers/net/ethernet/emulex/benet/be.h include/net/tcp.h net/mac802154/mac802154.h Most conflicts were minor overlapping stuff. The be2net driver brought in some fixes that added __vlan_put_tag calls, which in net-next take an additional argument. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-29net: tun: release the reference of tun device in tun_recvmsgGao feng
We forget to release the reference of tun device in tun_recvmsg. bug introduced in commit 54f968d6efdbf7dec36faa44fc11f01b0e4d1990 (tuntap: move socket to tun_file) Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-25tuntap: correct the return value in tun_set_iff()Jason Wang
commit (3be8fbab tuntap: fix error return code in tun_set_iff()) breaks the creation of multiqueue tuntap since it forbids to create more than one queues for a multiqueue tuntap device. We need return 0 instead -EBUSY here since we don't want to re-initialize the device when one or more queues has been already attached. Add a comment and correct the return value to zero. Reported-by: Jerry Chu <hkchu@google.com> Cc: Jerry Chu <hkchu@google.com> Cc: Wei Yongjun <weiyj.lk@gmail.com> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Jerry Chu <hkchu@google.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: drivers/net/ethernet/emulex/benet/be_main.c drivers/net/ethernet/intel/igb/igb_main.c drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c include/net/scm.h net/batman-adv/routing.c net/ipv4/tcp_input.c The e{uid,gid} --> {uid,gid} credentials fix conflicted with the cleanup in net-next to now pass cred structs around. The be2net driver had a bug fix in 'net' that overlapped with the VLAN interface changes by Patrick McHardy in net-next. An IGB conflict existed because in 'net' the build_skb() support was reverted, and in 'net-next' there was a comment style fix within that code. Several batman-adv conflicts were resolved by making sure that all calls to batadv_is_my_mac() are changed to have a new bat_priv first argument. Eric Dumazet's TS ECR fix in TCP in 'net' conflicted with the F-RTO rewrite in 'net-next', mostly overlapping changes. Thanks to Stephen Rothwell and Antonio Quartulli for help with several of these merge resolutions. Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-12tuntap: fix error return code in tun_set_iff()Wei Yongjun
Fix to return a negative error code from the error handling case instead of 0, as returned elsewhere in this function. [ Bug added in linux-3.8 , commit 4008e97f866db665 ("tuntap: fix ambigious multiqueue API") ] Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-11tuntap: initialize vlan_featuresJason Wang
The vlan_features was zero which prevents vlan GSO packets to be transmitted to userspace. This is suboptimal so enable this by initialize vlan_features for tuntap. Netperf shows better performance of guest receiving since vlan TSO works for tuntap: before: netperf -H 192.168.5.4 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.5.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.01 2786.67 after: netperf -H 192.168.5.4 MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.5.4 () port 0 AF_INET : demo Recv Send Send Socket Socket Message Elapsed Size Size Size Time Throughput bytes bytes bytes secs. 10^6bits/sec 87380 16384 16384 10.00 8085.49 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>