virtio-pci-modern: introduce helper to set/get queue_enable

This patch introduces a helper to set/get queue_enable for modern device.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210104065503.199631-12-jasowang@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c
index 05b21e18f46c498ac036b333e1b1927707d55967..0e62820b83ff10ddd2d7fddc02e91003657b7c3a 100644 (file)
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -234,6 +234,34 @@ static void vp_modern_queue_address(struct virtio_pci_modern_device *mdev,
                             &cfg->queue_used_hi);
 }
 
+/*
+ * vp_modern_set_queue_enable - enable a virtqueue
+ * @mdev: the modern virtio-pci device
+ * @index: the queue index
+ * @enable: whether the virtqueue is enable or not
+ */
+static void vp_modern_set_queue_enable(struct virtio_pci_modern_device *mdev,
+                                      u16 index, bool enable)
+{
+       vp_iowrite16(index, &mdev->common->queue_select);
+       vp_iowrite16(enable, &mdev->common->queue_enable);
+}
+
+/*
+ * vp_modern_get_queue_enable - enable a virtqueue
+ * @mdev: the modern virtio-pci device
+ * @index: the queue index
+ *
+ * Returns whether a virtqueue is enabled or not
+ */
+static bool vp_modern_get_queue_enable(struct virtio_pci_modern_device *mdev,
+                                      u16 index)
+{
+       vp_iowrite16(index, &mdev->common->queue_select);
+
+       return vp_ioread16(&mdev->common->queue_enable);
+}
+
 /* virtio config->finalize_features() implementation */
 static int vp_finalize_features(struct virtio_device *vdev)
 {
@@ -460,7 +488,7 @@ static struct virtqueue *setup_vq(struct virtio_pci_device *vp_dev,
 
        /* Check if queue is either not available or already active. */
        num = vp_ioread16(&cfg->queue_size);
-       if (!num || vp_ioread16(&cfg->queue_enable))
+       if (!num || vp_modern_get_queue_enable(mdev, index))
                return ERR_PTR(-ENOENT);
 
        if (num & (num - 1)) {
@@ -538,7 +566,6 @@ static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs,
                              struct irq_affinity *desc)
 {
        struct virtio_pci_device *vp_dev = to_vp_device(vdev);
-       struct virtio_pci_common_cfg __iomem *cfg = vp_dev->mdev.common;
        struct virtqueue *vq;
        int rc = vp_find_vqs(vdev, nvqs, vqs, callbacks, names, ctx, desc);
 
@@ -548,10 +575,8 @@ static int vp_modern_find_vqs(struct virtio_device *vdev, unsigned nvqs,
        /* Select and activate all queues. Has to be done last: once we do
         * this, there's no way to go back except reset.
         */
-       list_for_each_entry(vq, &vdev->vqs, list) {
-               vp_iowrite16(vq->index, &cfg->queue_select);
-               vp_iowrite16(1, &cfg->queue_enable);
-       }
+       list_for_each_entry(vq, &vdev->vqs, list)
+               vp_modern_set_queue_enable(&vp_dev->mdev, vq->index, true);
 
        return 0;
 }