Re: [PATCH v4 09/14] virtio: ethdev: check for vfio interface

On Fri, Jan 15, 2016 at 12:05 PM, Yuanhan Liu
[off-list ref] wrote:

On Thu, Jan 14, 2016 at 06:58:32PM +0530, Santosh Shukla wrote:

quoted

Introducing api to check interface type is vfio or not, if interface is vfio
then update struct virtio_vfio_dev {}.

Those two apis are:
- virtio_chk_for_vfio
- virtio_hw_init_by_vfio

Signed-off-by: Santosh Shukla <redacted>

..

quoted

+/* Init virtio by vfio-way */
+static int virtio_hw_init_by_vfio(struct virtio_hw *hw,
+                               struct rte_pci_device *pci_dev)
+{
+     struct virtio_vfio_dev *vdev;
+
+     vdev = &hw->dev;
+     if (virtio_chk_for_vfio(pci_dev) < 0) {
+             vdev->is_vfio = false;
+             vdev->pci_dev = NULL;
+             return -1;
+     }
+
+     /* .. So attached interface is vfio */
+     vdev->is_vfio = true;
+     vdev->pci_dev = pci_dev;

Normally, I don't like the way of adding yet another "virtio_hw_init_by_xxx".

As suggested in another reply, would pci_dev->kdrv checking be enough?
If so, do it in simple way.

No, It wont be enough, Virtio could only work for vfio for _noiommu_
mode and for that user need to preset -noiommu parameter, therefore
virtio need to check that parame. pci_dev->kdrv check not enough,
Hence not used.

        --ylu