linux-toradex.git/drivers/virtio, branch v3.10.58

virtio_balloon: don't softlockup on huge balloon changes.

2014-05-13T11:59:41+00:00

commit 1f74ef0f2d7d692fcd615621e0e734c3e7771413 upstream.

When adding or removing 100G from a balloon:

    BUG: soft lockup - CPU#0 stuck for 22s! [vballoon:367]

We have a wait_event_interruptible(), but the condition is always true
(more ballooning to do) so we don't ever sleep.  We also have a
wait_event() for the host to ack, but that is also always true as QEMU
is synchronous for balloon operations.

Reported-by: Gopesh Kumar Chaudhary 
Signed-off-by: Rusty Russell 
Signed-off-by: Greg Kroah-Hartman

virtio: support unlocked queue poll

2013-07-28T23:29:55+00:00

[ Upstream commit cc229884d3f77ec3b1240e467e0236c3e0647c0c ]

This adds a way to check ring empty state after enable_cb outside any
locks. Will be used by virtio_net.

Note: there's room for more optimization: caller is likely to have a
memory barrier already, which means we might be able to get rid of a
barrier here.  Deferring this optimization until we do some
benchmarking.

Signed-off-by: Michael S. Tsirkin 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

virtio_balloon: leak_balloon(): only tell host if we got pages deflated

2013-07-25T21:07:31+00:00

commit 8c6bab4f3874d31804a00782c48a8f244a0d3cc0 upstream.

balloon_page_dequeue() can return NULL.  If it does for the first page
being freed then leak_balloon() will create a scatter list with len=0.
Which in turn seems to generate an invalid virtio request.

I didn't get this in practice, I found it by code review.  On the other
hand, such an invalid virtio request will cause errors in QEMU and
fill_balloon() also performs the same check implemented by this commit.

This bug was introduced in e2250429.

Signed-off-by: Luiz Capitulino 
Acked-by: Rafael Aquini 
Signed-off-by: Andrew Morton 
Signed-off-by: Rusty Russell 
Signed-off-by: Greg Kroah-Hartman

virtio_balloon: use simplified virtqueue accessors.

2013-03-20T05:15:06+00:00

We never add buffers with input and output parts, so use the new accessors.

Signed-off-by: Rusty Russell

virtio_ring: virtqueue_add_outbuf / virtqueue_add_inbuf.

2013-03-20T05:14:52+00:00

These are specialized versions of virtqueue_add_buf(), which cover
over 80% of cases and are far clearer.

In particular, the scatterlists passed to these functions don't have
to be clean (ie. we ignore end markers).

Signed-off-by: Rusty Russell

virtio_ring: virtqueue_add_sgs, to add multiple sgs.

2013-03-20T05:13:29+00:00

virtio_scsi can really use this, to avoid the current hack of copying
the whole sg array.  Some other things get slightly neater, too.

This causes a slowdown in virtqueue_add_buf(), which is implemented as
a wrapper.  This is addressed in the next patches.

for i in `seq 50`; do /usr/bin/time -f 'Wall time:%e' ./vringh_test --indirect --eventidx --parallel --fast-vringh; done 2>&1 | stats --trim-outliers:

Before:
	Using CPUS 0 and 3
	Guest: notified 0, pinged 39009-39063(39062)
	Host: notified 39009-39063(39062), pinged 0
	Wall time:1.700000-1.950000(1.723542)

After:
	Using CPUS 0 and 3
	Guest: notified 0, pinged 39062-39063(39063)
	Host: notified 39062-39063(39063), pinged 0
	Wall time:1.760000-2.220000(1.789167)

Signed-off-by: Rusty Russell 
Reviewed-by: Wanlong Gao 
Reviewed-by: Asias He

virtio_ring: expose virtio barriers for use in vringh.

2013-03-20T03:30:41+00:00

The host side of ring needs this logic too.

Signed-off-by: Rusty Russell

Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2013-02-26T22:49:12+00:00

Pull virtio updates from Rusty Russell:
 "All trivial, thanks to the stuff which didn't quite make it time"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_console: Initialize guest_connected=true for rproc_serial
  virtio: use module_virtio_driver.
  virtio: Add module driver macro for virtio drivers.
  virtio_console: Use virtio device index to generate port name
  virtio: make pci_device_id const
  virtio: make config_ops const
  virtio-mmio: fix wrong comment about register offset
  virtio_console: Let unconnected rproc device receive data.

virtio: use module_virtio_driver.

2013-02-13T06:30:37+00:00

Signed-off-by: Rusty Russell

virtio: make pci_device_id const

2013-02-11T05:02:18+00:00

Use DEVICE_TABLE macro which also makes table const.

Signed-off-by: Stephen Hemminger 
Signed-off-by: Rusty Russell