From 8c797e758ad41b8dd6ea6f72c6f0194dedb30a2f Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Thu, 12 Jan 2017 23:26:22 +0200 Subject: [PATCH] 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: Michael S. Tsirkin Message-Id: <1484256243-1982-1-git-send-email-mst@redhat.com> Signed-off-by: Cornelia Huck --- hw/s390x/virtio-ccw.c | 2 +- hw/virtio/virtio.c | 5 +++++ include/hw/virtio/virtio.h | 1 + 3 files changed, 7 insertions(+), 1 deletion(-) diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c index 07650683f7..63c46373fb 100644 --- a/hw/s390x/virtio-ccw.c +++ b/hw/s390x/virtio-ccw.c @@ -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; } diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index aa4f38f50a..94d7dbae6c 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -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; diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index e5541c61f7..6523bacd2f 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -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); -- 2.11.4.GIT