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@xxxxxxxxx> Acked-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx> Acked-by: Michael S. Tsirkin <mst@xxxxxxxxxx> --- v2: - Disable VFs when unbinding the driver (Alex, MST); - Don't use pci_sriov_configure_simple (Alex); drivers/virtio/virtio_pci_common.c | 30 ++++++++++++++++++++++++++++++ drivers/virtio/virtio_pci_modern.c | 14 ++++++++++++++ include/uapi/linux/virtio_config.h | 7 ++++++- 3 files changed, 50 insertions(+), 1 deletion(-) diff --git a/drivers/virtio/virtio_pci_common.c b/drivers/virtio/virtio_pci_common.c index 48d4d1cf1cb6..1d4467b2dc31 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); diff --git a/drivers/virtio/virtio_pci_modern.c b/drivers/virtio/virtio_pci_modern.c index 2555d80f6eec..07571daccfec 100644 --- a/drivers/virtio/virtio_pci_modern.c +++ b/drivers/virtio/virtio_pci_modern.c @@ -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"); diff --git a/include/uapi/linux/virtio_config.h b/include/uapi/linux/virtio_config.h index 308e2096291f..b7c1f4e7d59e 100644 --- a/include/uapi/linux/virtio_config.h +++ b/include/uapi/linux/virtio_config.h @@ -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 */ -- 2.17.0
