The MMIO virtio transport spec allows the guest to tell the host how large the queue size is. Add virtio_queue_set_num() function which implements this in the QEMU common virtio support code.
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> Message-id: 1373977512-28932-4-git-send-email-peter.mayd...@linaro.org --- hw/virtio/virtio.c | 8 ++++++++ include/hw/virtio/virtio.h | 1 + 2 files changed, 9 insertions(+) diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index 8176c14..01b05f3 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -667,6 +667,14 @@ hwaddr virtio_queue_get_addr(VirtIODevice *vdev, int n) return vdev->vq[n].pa; } +void virtio_queue_set_num(VirtIODevice *vdev, int n, int num) +{ + if (num <= VIRTQUEUE_MAX_SIZE) { + vdev->vq[n].vring.num = num; + virtqueue_init(&vdev->vq[n]); + } +} + int virtio_queue_get_num(VirtIODevice *vdev, int n) { return vdev->vq[n].vring.num; diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h index 5d1d2be..65f378d 100644 --- a/include/hw/virtio/virtio.h +++ b/include/hw/virtio/virtio.h @@ -200,6 +200,7 @@ void virtio_config_writew(VirtIODevice *vdev, uint32_t addr, uint32_t data); void virtio_config_writel(VirtIODevice *vdev, uint32_t addr, uint32_t data); 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); void virtio_queue_notify(VirtIODevice *vdev, int n); uint16_t virtio_queue_vector(VirtIODevice *vdev, int n); -- 1.7.9.5