This series introduce a vfio driver over virtio devices to support the legacy interface functionality for VFs. Background, from the virtio spec [1]. -------------------------------------------------------------------- In some systems, there is a need to support a virtio legacy driver with a device that does not directly support the legacy interface. In such scenarios, a group owner device can provide the legacy interface functionality for the group member devices. The driver of the owner device can then access the legacy interface of a member device on behalf of the legacy member device driver. For example, with the SR-IOV group type, group members (VFs) can not present the legacy interface in an I/O BAR in BAR0 as expected by the legacy pci driver. If the legacy driver is running inside a virtual machine, the hypervisor executing the virtual machine can present a virtual device with an I/O BAR in BAR0. The hypervisor intercepts the legacy driver accesses to this I/O BAR and forwards them to the group owner device (PF) using group administration commands. -------------------------------------------------------------------- The first 7 patches are in the virtio area and handle the below: - Introduce the admin virtqueue infrastcture. - Expose APIs to enable upper layers as of vfio, net, etc to execute admin commands. - Expose the layout of the commands that should be used for supporting the legacy access. The above follows the virtio spec that was lastly accepted in that area [1]. The last 4 patches are in the vfio area and handle the below: - Expose some APIs from vfio/pci to be used by the vfio/virtio driver. - Expose admin commands over virtio device. - Introduce a vfio driver over virtio devices to support the legacy interface functionality for VFs. The series was tested successfully over virtio-net VFs in the host, while running in the guest both modern and legacy drivers. [1] https://github.com/oasis-tcs/virtio-spec/commit/03c2d32e5093ca9f2a17797242fbef88efe94b8c Yishai Feng Liu (7): virtio-pci: Use virtio pci device layer vq info instead of generic one virtio: Define feature bit for administration virtqueue virtio-pci: Introduce admin virtqueue virtio: Expose the synchronous command helper function virtio-pci: Introduce admin command sending function virtio-pci: Introduce API to get PF virtio device from VF PCI device virtio-pci: Introduce admin commands Yishai Hadas (4): vfio/pci: Expose vfio_pci_core_setup_barmap() vfio/pci: Expose vfio_pci_iowrite/read##size() vfio/virtio: Expose admin commands over virtio device vfio/virtio: Introduce a vfio driver over virtio devices MAINTAINERS | 6 + drivers/net/virtio_net.c | 21 +- drivers/vfio/pci/Kconfig | 2 + drivers/vfio/pci/Makefile | 2 + drivers/vfio/pci/vfio_pci_core.c | 25 ++ drivers/vfio/pci/vfio_pci_rdwr.c | 38 +- drivers/vfio/pci/virtio/Kconfig | 15 + drivers/vfio/pci/virtio/Makefile | 4 + drivers/vfio/pci/virtio/cmd.c | 146 +++++++ drivers/vfio/pci/virtio/cmd.h | 35 ++ drivers/vfio/pci/virtio/main.c | 546 +++++++++++++++++++++++++ drivers/virtio/Makefile | 2 +- drivers/virtio/virtio.c | 44 +- drivers/virtio/virtio_pci_common.c | 24 +- drivers/virtio/virtio_pci_common.h | 17 +- drivers/virtio/virtio_pci_modern.c | 12 +- drivers/virtio/virtio_pci_modern_avq.c | 138 +++++++ drivers/virtio/virtio_ring.c | 27 ++ include/linux/vfio_pci_core.h | 20 + include/linux/virtio.h | 19 + include/linux/virtio_config.h | 7 + include/linux/virtio_pci_modern.h | 3 + include/uapi/linux/virtio_config.h | 8 +- include/uapi/linux/virtio_pci.h | 66 +++ 24 files changed, 1171 insertions(+), 56 deletions(-) create mode 100644 drivers/vfio/pci/virtio/Kconfig create mode 100644 drivers/vfio/pci/virtio/Makefile create mode 100644 drivers/vfio/pci/virtio/cmd.c create mode 100644 drivers/vfio/pci/virtio/cmd.h create mode 100644 drivers/vfio/pci/virtio/main.c create mode 100644 drivers/virtio/virtio_pci_modern_avq.c -- 2.27.0
