virtio_pci: support enabling VFs
There is a new feature bit allocated in virtio spec to
support SR-IOV (Single Root I/O Virtualization):
https://github.com/oasis-tcs/virtio-spec/issues/11
This patch enables the support for this feature bit in
virtio driver.
Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c
index 48d4d1c..1d4467b 100644
--- a/drivers/virtio/virtio_pci_common.c
+++ b/drivers/virtio/virtio_pci_common.c
@@ -577,6 +577,8 @@ static void virtio_pci_remove(struct pci_dev *pci_dev)
struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
struct device *dev = get_device(&vp_dev->vdev.dev);
+ pci_disable_sriov(pci_dev);
+
unregister_virtio_device(&vp_dev->vdev);
if (vp_dev->ioaddr)
@@ -588,6 +590,33 @@ static void virtio_pci_remove(struct pci_dev *pci_dev)
put_device(dev);
}
+static int virtio_pci_sriov_configure(struct pci_dev *pci_dev, int num_vfs)
+{
+ struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
+ struct virtio_device *vdev = &vp_dev->vdev;
+ int ret;
+
+ if (!(vdev->config->get_status(vdev) & VIRTIO_CONFIG_S_DRIVER_OK))
+ return -EBUSY;
+
+ if (!__virtio_test_bit(vdev, VIRTIO_F_SR_IOV))
+ return -EINVAL;
+
+ if (pci_vfs_assigned(pci_dev))
+ return -EPERM;
+
+ if (num_vfs == 0) {
+ pci_disable_sriov(pci_dev);
+ return 0;
+ }
+
+ ret = pci_enable_sriov(pci_dev, num_vfs);
+ if (ret < 0)
+ return ret;
+
+ return num_vfs;
+}
+
static struct pci_driver virtio_pci_driver = {
.name = "virtio-pci",
.id_table = virtio_pci_id_table,
@@ -596,6 +625,7 @@ static struct pci_driver virtio_pci_driver = {
#ifdef CONFIG_PM_SLEEP
.driver.pm = &virtio_pci_pm_ops,
#endif
+ .sriov_configure = virtio_pci_sriov_configure,
};
module_pci_driver(virtio_pci_driver);