linux-toradex.git/drivers/vhost/net.c, branch v3.2.15

vhost: handle wrap around in # of bufs math

2011-07-21T07:48:27+00:00

The meth for calculating the # of outstanding buffers gives
incorrect results when vq->upend_idx wraps around zero.
Fix that.

Signed-off-by: Shirley Ma 
Signed-off-by: Michael S. Tsirkin

vhost-net: update used ring on backend change

2011-07-21T07:23:31+00:00

On backend change, we flushed out outstanding skbs
but forgot to update the used ring, so that
done entries were left in the ubuf_info ring.
As a result we lose heads or complete incorrect ones,
crashing the guest or leaking memory.
Fix by updating the used ring.

Signed-off-by: Michael S. Tsirkin

vhost: init used ring after backend was set

2011-07-19T10:28:34+00:00

Move the used ring initialization after backend was set. This
makes it possible to disable the backend and tweak the used ring,
then restart. This will also make it possible to log the used ring
write correctly.

Signed-off-by: Jason Wang 
Signed-off-by: Michael S. Tsirkin

vhost: vhost TX zero-copy support

2011-07-18T17:42:32+00:00

>From: Shirley Ma 

This adds experimental zero copy support in vhost-net,
disabled by default. To enable, set
experimental_zcopytx module option to 1.

This patch maintains the outstanding userspace buffers in the
sequence it is delivered to vhost. The outstanding userspace buffers
will be marked as done once the lower device buffers DMA has finished.
This is monitored through last reference of kfree_skb callback. Two
buffer indices are used for this purpose.

The vhost-net device passes the userspace buffers info to lower device
skb through message control. DMA done status check and guest
notification are handled by handle_tx: in the worst case is all buffers
in the vq are in pending/done status, so we need to notify guest to
release DMA done buffers first before we get any new buffers from the
vq.

One known problem is that if the guest stops submitting
buffers, buffers might never get used until some
further action, e.g. device reset. This does not
seem to affect linux guests.

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

vhost: support event index

2011-05-30T01:44:15+00:00

Support the new event index feature. When acked,
utilize it to reduce the # of interrupts sent to the guest.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: Rusty Russell

vhost-net: remove unlocked use of receive_queue

2011-03-13T21:08:19+00:00

Use of skb_queue_empty(&sock->sk->sk_receive_queue)
without taking the sk_receive_queue.lock is unsafe
or useless. Take it out.

Reported-by:  Eric Dumazet 
Signed-off-by: Michael S. Tsirkin

vhost: lock receive queue, not the socket

2011-03-13T21:08:04+00:00

vhost takes a sock lock to try and prevent
the skb from being pulled from the receive queue
after skb_peek.  However this is not the right lock to use for that,
sk_receive_queue.lock is. Fix that up.

Signed-off-by: Michael S. Tsirkin

vhost-net: Unify the code of mergeable and big buffer handling

2011-03-13T15:00:10+00:00

Codes duplication were found between the handling of mergeable and big
buffers, so this patch tries to unify them. This could be easily done
by adding a quota to the get_rx_bufs() which is used to limit the
number of buffers it returns (for mergeable buffer, the quota is
simply UIO_MAXIOV, for big buffers, the quota is just 1), and then the
previous handle_rx_mergeable() could be resued also for big buffers.

Signed-off-by: Jason Wang 
Signed-off-by: Michael S. Tsirkin

vhost-net: check the support of mergeable buffer outside the receive loop

2011-03-13T14:57:30+00:00

No need to check the support of mergeable buffer inside the recevie
loop as the whole handle_rx()_xx is in the read critical region.  So
this patch move it ahead of the receiving loop.

Signed-off-by: Jason Wang 
Signed-off-by: Michael S. Tsirkin

vhost: Cleanup vhost.c and net.c

2011-03-08T16:02:47+00:00

Minor cleanup of vhost.c and net.c to match coding style.

Signed-off-by: Krishna Kumar 
Signed-off-by: Michael S. Tsirkin