summaryrefslogtreecommitdiff
path: root/drivers/char
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2016-09-10 00:52:05 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2016-09-10 00:52:05 +0300
commitd0acc7dfd90eb97e90ccd42a567034017ec60fb8 (patch)
tree38650e8e367943cdb1dda7edf3e7a857947aac7f /drivers/char
parentdaf6b9b68fca57effe3fcf74a8528f17516c420f (diff)
parent5e59d9a1aed26abcc79abe78af5cfd34e53cbe7f (diff)
downloadlinux-d0acc7dfd90eb97e90ccd42a567034017ec60fb8.tar.xz
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio fixes from Michael Tsirkin: "This includes a couple of bugfixs for virtio. The virtio console patch is actually also in x86/tip targeting 4.9 because it helps vmap stacks, but it also fixes IOMMU_PLATFORM which was added in 4.8, and it seems important not to ship that in a broken configuration" * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: virtio_console: Stop doing DMA on the stack virtio: mark vring_dma_dev() static
Diffstat (limited to 'drivers/char')
-rw-r--r--drivers/char/virtio_console.c23
1 files changed, 15 insertions, 8 deletions
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index d2406fe25533..5da47e26a012 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -165,6 +165,12 @@ struct ports_device {
*/
struct virtqueue *c_ivq, *c_ovq;
+ /*
+ * A control packet buffer for guest->host requests, protected
+ * by c_ovq_lock.
+ */
+ struct virtio_console_control cpkt;
+
/* Array of per-port IO virtqueues */
struct virtqueue **in_vqs, **out_vqs;
@@ -560,28 +566,29 @@ static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
unsigned int event, unsigned int value)
{
struct scatterlist sg[1];
- struct virtio_console_control cpkt;
struct virtqueue *vq;
unsigned int len;
if (!use_multiport(portdev))
return 0;
- cpkt.id = cpu_to_virtio32(portdev->vdev, port_id);
- cpkt.event = cpu_to_virtio16(portdev->vdev, event);
- cpkt.value = cpu_to_virtio16(portdev->vdev, value);
-
vq = portdev->c_ovq;
- sg_init_one(sg, &cpkt, sizeof(cpkt));
-
spin_lock(&portdev->c_ovq_lock);
- if (virtqueue_add_outbuf(vq, sg, 1, &cpkt, GFP_ATOMIC) == 0) {
+
+ portdev->cpkt.id = cpu_to_virtio32(portdev->vdev, port_id);
+ portdev->cpkt.event = cpu_to_virtio16(portdev->vdev, event);
+ portdev->cpkt.value = cpu_to_virtio16(portdev->vdev, value);
+
+ sg_init_one(sg, &portdev->cpkt, sizeof(struct virtio_console_control));
+
+ if (virtqueue_add_outbuf(vq, sg, 1, &portdev->cpkt, GFP_ATOMIC) == 0) {
virtqueue_kick(vq);
while (!virtqueue_get_buf(vq, &len)
&& !virtqueue_is_broken(vq))
cpu_relax();
}
+
spin_unlock(&portdev->c_ovq_lock);
return 0;
}