linux.git/drivers/net/macvtap.c, branch v2.6.38

drivers/net/macvtap: fix error check

2011-03-07T23:57:58+00:00

'len' is unsigned of type size_t and can't be negative.

Signed-off-by: Nicolas Kaiser 
Acked-by: Arnd Bergmann 
Signed-off-by: David S. Miller

net: remove dev_txq_stats_fold()

2011-01-14T05:44:34+00:00

After recent changes, (percpu stats on vlan/tunnels...), we dont need
anymore per struct netdev_queue tx_bytes/tx_packets/tx_dropped counters.

Only remaining users are ixgbe, sch_teql, gianfar & macvlan :

1) ixgbe can be converted to use existing tx_ring counters.

2) macvlan incremented txq->tx_dropped, it can use the
dev->stats.tx_dropped counter.

3) sch_teql : almost revert ab35cd4b8f42 (Use net_device internal stats)
    Now we have ndo_get_stats64(), use it, even for "unsigned long"
fields (No need to bring back a struct net_device_stats)

4) gianfar adds a stats structure per tx queue to hold
tx_bytes/tx_packets

This removes a lockdep warning (and possible lockup) in rndis gadget,
calling dev_get_stats() from hard IRQ context.

Ref: http://www.spinics.net/lists/netdev/msg149202.html

Reported-by: Neil Jones 
Signed-off-by: Eric Dumazet 
CC: Jarek Poplawski 
CC: Alexander Duyck 
CC: Jeff Kirsher 
CC: Sandeep Gopalpet 
CC: Michal Nazarewicz 
Signed-off-by: David S. Miller

net: Use skb_checksum_start_offset()

2010-12-16T22:43:14+00:00

Replace skb->csum_start - skb_headroom(skb) with skb_checksum_start_offset().

Note for usb/smsc95xx: skb->data - skb->head == skb_headroom(skb).

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

macvtap: Implement multiqueue for macvtap driver

2010-08-17T04:06:25+00:00

Implement multiqueue facility for macvtap driver. The idea is that
a macvtap device can be opened multiple times and the fd's can be
used to register eg, as backend for vhost.

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

Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

2010-07-28T04:01:35+00:00

Conflicts:
	drivers/net/bnx2x_main.c

Merge bnx2x bug fixes in by hand... :-/

Signed-off-by: David S. Miller

macvtap: Limit packet queue length

2010-07-22T20:08:56+00:00

Mark Wagner reported OOM symptoms when sending UDP traffic over
a macvtap link to a kvm receiver.

This appears to be caused by the fact that macvtap packet queues
are unlimited in length.  This means that if the receiver can't
keep up with the rate of flow, then we will hit OOM. Of course
it gets worse if the OOM killer then decides to kill the receiver.

This patch imposes a cap on the packet queue length, in the same
way as the tuntap driver, using the device TX queue length.

Please note that macvtap currently has no way of giving congestion
notification, that means the software device TX queue cannot be
used and packets will always be dropped once the macvtap driver
queue fills up.

This shouldn't be a great problem for the scenario where macvtap
is used to feed a kvm receiver, as the traffic is most likely
external in origin so congestion notification can't be applied
anyway.

Of course, if anybody decides to complain about guest-to-guest
UDP packet loss down the track, then we may have to revisit this.

Incidentally, this patch also fixes a real memory leak when
macvtap_get_queue fails.

Chris Wright noticed that for this patch to work, we need a
non-zero TX queue length.  This patch includes his work to change
the default macvtap TX queue length to 500.

Reported-by: Mark Wagner 
Signed-off-by: Herbert Xu 
Acked-by: Chris Wright 
Acked-by: Arnd Bergmann 
Signed-off-by: David S. Miller

macvtap: Use dev_t for macvtap_major.

2010-07-11T02:25:50+00:00

Reported-by: "Robert P. J. Day" 
Signed-off-by: David S. Miller

macvtap: add ioctl to modify vnet header size

2010-05-03T22:35:47+00:00

This adds TUNSETVNETHDRSZ/TUNGETVNETHDRSZ support
to macvtap.

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

net: sock_def_readable() and friends RCU conversion

2010-05-01T22:00:15+00:00

sk_callback_lock rwlock actually protects sk->sk_sleep pointer, so we
need two atomic operations (and associated dirtying) per incoming
packet.

RCU conversion is pretty much needed :

1) Add a new structure, called "struct socket_wq" to hold all fields
that will need rcu_read_lock() protection (currently: a
wait_queue_head_t and a struct fasync_struct pointer).

[Future patch will add a list anchor for wakeup coalescing]

2) Attach one of such structure to each "struct socket" created in
sock_alloc_inode().

3) Respect RCU grace period when freeing a "struct socket_wq"

4) Change sk_sleep pointer in "struct sock" by sk_wq, pointer to "struct
socket_wq"

5) Change sk_sleep() function to use new sk->sk_wq instead of
sk->sk_sleep

6) Change sk_has_sleeper() to wq_has_sleeper() that must be used inside
a rcu_read_lock() section.

7) Change all sk_has_sleeper() callers to :
  - Use rcu_read_lock() instead of read_lock(&sk->sk_callback_lock)
  - Use wq_has_sleeper() to eventually wakeup tasks.
  - Use rcu_read_unlock() instead of read_unlock(&sk->sk_callback_lock)

8) sock_wake_async() is modified to use rcu protection as well.

9) Exceptions :
  macvtap, drivers/net/tun.c, af_unix use integrated "struct socket_wq"
instead of dynamically allocated ones. They dont need rcu freeing.

Some cleanups or followups are probably needed, (possible
sk_callback_lock conversion to a spinlock for example...).

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

net: use sk_sleep()

2010-04-26T18:18:45+00:00

Commit aa395145 (net: sk_sleep() helper) missed three files in the
conversion.

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