Commit 8c797e75 authored by Michael S. Tsirkin's avatar Michael S. Tsirkin Committed by Cornelia Huck
Browse files

virtio-ccw: fix ring sizing 



Current code seems to assume ring size is
always decreased but this is not required by spec:
what spec says is just that size can not exceed
the maximum. Fix it up.

Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Message-Id: <1484256243-1982-1-git-send-email-mst@redhat.com>
Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
parent 857cc719

hw/s390x/virtio-ccw.c

+1 −1
Original line number Diff line number Diff line
@@ -149,7 +149,7 @@ static int virtio_ccw_set_vqs(SubchDev *sch, VqInfoBlock *info, 
    } else {

        if (info) {

            /* virtio-1 allows changing the ring size. */

            if (virtio_queue_get_num(vdev, index) < num) {

            if (virtio_queue_get_max_num(vdev, index) < num) {

                /* Fail if we exceed the maximum number. */

                return -EINVAL;

            }

hw/virtio/virtio.c

+5 −0
Original line number Diff line number Diff line
@@ -1262,6 +1262,11 @@ int virtio_queue_get_num(VirtIODevice *vdev, int n) 
    return vdev->vq[n].vring.num;

}



int virtio_queue_get_max_num(VirtIODevice *vdev, int n)

{

    return vdev->vq[n].vring.num_default;

}



int virtio_get_num_queues(VirtIODevice *vdev)

{

    int i;

include/hw/virtio/virtio.h

+1 −0
Original line number Diff line number Diff line
@@ -228,6 +228,7 @@ void virtio_queue_set_addr(VirtIODevice *vdev, int n, hwaddr addr); 
hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n);

void virtio_queue_set_num(VirtIODevice *vdev, int n, int num);

int virtio_queue_get_num(VirtIODevice *vdev, int n);

int virtio_queue_get_max_num(VirtIODevice *vdev, int n);

int virtio_get_num_queues(VirtIODevice *vdev);

void virtio_queue_set_rings(VirtIODevice *vdev, int n, hwaddr desc,

                            hwaddr avail, hwaddr used);