[RFC V2 1/4] VFIO: Probe new devices in a live VFIO group with the VFIO driver

Ilya Lesokhin
2016-02-04T08:28:54Z

When a new device is added to a live VFIO group,
use driver_override to force the device to be probed by
the VFIO driver.

Signed-off-by: Ilya Lesokhin <ilyal@mellanox.com>
---
drivers/vfio/vfio.c | 18 +++++++++++++++---
1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index 563c510..176647e 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -504,6 +504,7 @@ static int vfio_dev_viable(struct device *dev, void *data)
static int vfio_group_nb_add_dev(struct vfio_group *group, struct device *dev)
{
struct vfio_device *device;
+ struct pci_dev *pdev;

/* Do we already know about it? We shouldn't */
device = vfio_group_get_device(group, dev);
@@ -516,9 +517,20 @@ static int vfio_group_nb_add_dev(struct vfio_group *group, struct device *dev)
if (!atomic_read(&group->container_users))
return 0;

- /* TODO Prevent device auto probing */
- WARN("Device %s added to live group %d!\n", dev_name(dev),
- iommu_group_id(group->iommu_group));
+ if (dev_is_pci(dev)) {
+ /* a device that shares a group with another VFIO
+ * device should also be probed by VFIO
+ */
+ pdev = to_pci_dev(dev);
+ if (pdev->driver_override)
+ kfree(pdev->driver_override);
+
+ pdev->driver_override = kstrdup("vfio-pci", GFP_KERNEL);
+ } else {
+ /* TODO Prevent device auto probing */
+ WARN("Device %s added to live group %d!\n", dev_name(dev),
+ iommu_group_id(group->iommu_group));
+ }

return 0;
}
--
1.8.3.1