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>
This commit is contained in:
Tiwei Bie 2018-06-01 12:02:39 +08:00 committed by Michael S. Tsirkin
parent 670ae9caac
commit cfecc2918d
3 changed files with 50 additions and 1 deletions

View file

@ -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);

View file

@ -153,14 +153,28 @@ static u64 vp_get_features(struct virtio_device *vdev)
return features;
}
static void vp_transport_features(struct virtio_device *vdev, u64 features)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
struct pci_dev *pci_dev = vp_dev->pci_dev;
if ((features & BIT_ULL(VIRTIO_F_SR_IOV)) &&
pci_find_ext_capability(pci_dev, PCI_EXT_CAP_ID_SRIOV))
__virtio_set_bit(vdev, VIRTIO_F_SR_IOV);
}
/* virtio config->finalize_features() implementation */
static int vp_finalize_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
u64 features = vdev->features;
/* Give virtio_ring a chance to accept features. */
vring_transport_features(vdev);
/* Give virtio_pci a chance to accept features. */
vp_transport_features(vdev, features);
if (!__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
dev_err(&vdev->dev, "virtio: device uses modern interface "
"but does not have VIRTIO_F_VERSION_1\n");

View file

@ -49,7 +49,7 @@
* transport being used (eg. virtio_ring), the rest are per-device feature
* bits. */
#define VIRTIO_TRANSPORT_F_START 28
#define VIRTIO_TRANSPORT_F_END 34
#define VIRTIO_TRANSPORT_F_END 38
#ifndef VIRTIO_CONFIG_NO_LEGACY
/* Do we get callbacks when the ring is completely used, even if we've
@ -71,4 +71,9 @@
* this is for compatibility with legacy systems.
*/
#define VIRTIO_F_IOMMU_PLATFORM 33
/*
* Does the device support Single Root I/O Virtualization?
*/
#define VIRTIO_F_SR_IOV 37
#endif /* _UAPI_LINUX_VIRTIO_CONFIG_H */