From 805d782d284cba013707d5edf38b04047b21d4b5 Mon Sep 17 00:00:00 2001 From: Xuan Zhuo Date: Mon, 17 Oct 2022 17:25:48 +0800 Subject: virtio-pci: support queue reset PCI devices support vq reset. Based on this function, the driver can adjust the size of the ring, and quickly recycle the buffer in the ring. The migration of the virtio devices will not happen during a reset operation. This is becuase the global iothread lock is held. Migration thread also needs the lock. As a result, when migration of virtio devices starts, the 'reset' status of VirtIOPCIQueue will always be 0. Thus, we do not need to add it in vmstate_virtio_pci_modern_queue_state. Signed-off-by: Xuan Zhuo Signed-off-by: Kangjie Xu Acked-by: Jason Wang Message-Id: <20221017092558.111082-6-xuanzhuo@linux.alibaba.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/virtio/virtio-pci.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'hw') diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c index 34db51e241..d4f2ffe986 100644 --- a/hw/virtio/virtio-pci.c +++ b/hw/virtio/virtio-pci.c @@ -1251,6 +1251,9 @@ static uint64_t virtio_pci_common_read(void *opaque, hwaddr addr, case VIRTIO_PCI_COMMON_Q_USEDHI: val = proxy->vqs[vdev->queue_sel].used[1]; break; + case VIRTIO_PCI_COMMON_Q_RESET: + val = proxy->vqs[vdev->queue_sel].reset; + break; default: val = 0; } @@ -1338,6 +1341,7 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, ((uint64_t)proxy->vqs[vdev->queue_sel].used[1]) << 32 | proxy->vqs[vdev->queue_sel].used[0]); proxy->vqs[vdev->queue_sel].enabled = 1; + proxy->vqs[vdev->queue_sel].reset = 0; } else { virtio_error(vdev, "wrong value for queue_enable %"PRIx64, val); } @@ -1360,6 +1364,16 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr, case VIRTIO_PCI_COMMON_Q_USEDHI: proxy->vqs[vdev->queue_sel].used[1] = val; break; + case VIRTIO_PCI_COMMON_Q_RESET: + if (val == 1) { + proxy->vqs[vdev->queue_sel].reset = 1; + + virtio_queue_reset(vdev, vdev->queue_sel); + + proxy->vqs[vdev->queue_sel].reset = 0; + proxy->vqs[vdev->queue_sel].enabled = 0; + } + break; default: break; } @@ -1954,6 +1968,7 @@ static void virtio_pci_reset(DeviceState *qdev) for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { proxy->vqs[i].enabled = 0; + proxy->vqs[i].reset = 0; proxy->vqs[i].num = 0; proxy->vqs[i].desc[0] = proxy->vqs[i].desc[1] = 0; proxy->vqs[i].avail[0] = proxy->vqs[i].avail[1] = 0; -- cgit v1.2.3