linux.git/include/linux/if_tun.h, branch v4.16-rc4

tuntap: fix for "tuntap: XDP transmission"

2018-01-10T20:52:49+00:00

Fixes: fc72d1d54dd9 ("tuntap: XDP transmission")
Signed-off-by: Stephen Rothwell 
Acked-by: Jason Wang 
Signed-off-by: David S. Miller

tuntap: XDP transmission

2018-01-09T15:57:08+00:00

This patch implements XDP transmission for TAP. Since we can't create
new queues for TAP during XDP set, exist ptr_ring was reused for
queuing XDP buffers. To differ xdp_buff from sk_buff, TUN_XDP_FLAG
(0x1UL) was encoded into lowest bit of xpd_buff pointer during
ptr_ring_produce, and was decoded during consuming. XDP metadata was
stored in the headroom of the packet which should work in most of
cases since driver usually reserve enough headroom. Very minor changes
were done for vhost_net: it just need to peek the length depends on
the type of pointer.

Tests were done on two Intel E5-2630 2.40GHz machines connected back
to back through two 82599ES. Traffic were generated/received through
MoonGen/testpmd(rxonly). It reports ~20% improvements when
xdp_redirect_map is doing redirection from ixgbe to TAP (from 2.50Mpps
to 3.05Mpps)

Cc: Jesper Dangaard Brouer 
Signed-off-by: Jason Wang 
Signed-off-by: David S. Miller

tun/tap: use ptr_ring instead of skb_array

2018-01-09T15:56:10+00:00

This patch switches to use ptr_ring instead of skb_array. This will be
used to enqueue different types of pointers by encoding type into
lower bits.

Signed-off-by: Jason Wang 
Signed-off-by: David S. Miller

tun: export skb_array

2017-05-18T14:07:40+00:00

This patch exports skb_array through tun_get_skb_array(). Caller can
then manipulate skb array directly.

Signed-off-by: Jason Wang 
Signed-off-by: David S. Miller

UAPI: (Scripted) Disintegrate include/linux

2012-10-13T09:46:48+00:00

Signed-off-by: David Howells 
Acked-by: Arnd Bergmann 
Acked-by: Thomas Gleixner 
Acked-by: Michael Kerrisk 
Acked-by: Paul E. McKenney 
Acked-by: Dave Jones

tun: add ioctl to modify vnet header size

2010-05-03T09:33:13+00:00

virtio added mergeable buffers mode where 2 bytes of extra info is put
after vnet header but before actual data (tun does not need this data).
In hindsight, it would have been better to add the new info *before* the
packet: as it is, users need a lot of tricky code to skip the extra 2
bytes in the middle of the iovec, and in fact applications seem to get
it wrong, and only work with specific iovec layout.  The fact we might
need to split iovec also means we might in theory overflow iovec max
size.

This patch adds a simpler way for applications to handle this,
and future proofs the interface against further extensions,
by making the size of the virtio net header configurable
from userspace. As a result, tun driver will simply
skip the extra 2 bytes on both input and output.

Signed-off-by: Michael S. Tsirkin 
Acked-by: David S. Miller

tun: socket filter support

2010-02-18T00:35:17+00:00

This patch adds Linux Socket Filter support to
tun driver.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller

tun: export underlying socket

2010-01-15T09:43:28+00:00

Tun device looks similar to a packet socket
in that both pass complete frames from/to userspace.

This patch fills in enough fields in the socket underlying tun driver
to support sendmsg/recvmsg operations, and message flags
MSG_TRUNC and MSG_DONTWAIT, and exports access to this socket
to modules.  Regular read/write behaviour is unchanged.

This way, code using raw sockets to inject packets
into a physical device, can support injecting
packets into host network stack almost without modification.

First user of this interface will be vhost virtualization
accelerator.

Signed-off-by: Michael S. Tsirkin 
Acked-by: Herbert Xu 
Acked-by: David S. Miller 
Signed-off-by: David S. Miller

tun: Allow tap device to send/receive UFO packets.

2009-07-17T17:11:00+00:00

- Allow setting UFO on tap device and handle UFO packets.

Signed-off-by: Sridhar Samudrala 

---------------------------------------------------------
Signed-off-by: David S. Miller

tun: add IFF_TUN_EXCL flag to avoid opening a persistent device.

2009-04-27T10:23:54+00:00

When creating a certain types of VPN, NetworkManager will first attempt
to find an available tun device by iterating through 'vpn%d' until it
finds one that isn't already busy. Then it'll set that to be persistent
and owned by the otherwise unprivileged user that the VPN dæmon itself
runs as.

There's a race condition here -- during the period where the vpn%d
device is created and we're waiting for the VPN dæmon to actually
connect and use it, if we try to create _another_ device we could end up
re-using the same one -- because trying to open it again doesn't get
-EBUSY as it would while it's _actually_ busy.

So solve this, we add an IFF_TUN_EXCL flag which causes tun_set_iff() to
fail if it would be opening an existing persistent tundevice -- so that
we can make sure we're getting an entirely _new_ device.

Signed-off-by: David Woodhouse 
Signed-off-by: David S. Miller