Re: [PATCH V2 0/8] mdev based hardware virtio offloading support

Jason Wang
2019-09-25T12:13:29Z

On 2019/9/25 下午4:24, Tian, Kevin wrote:
>> From: Jason Wang [mailto:jasowang@redhat.com]
>> Sent: Tuesday, September 24, 2019 9:53 PM
>>
>> Hi all:
>>
>> There are hardware that can do virtio datapath offloading while having
>> its own control path. This path tries to implement a mdev based
>> unified API to support using kernel virtio driver to drive those
>> devices. This is done by introducing a new mdev transport for virtio
>> (virtio_mdev) and register itself as a new kind of mdev driver. Then
>> it provides a unified way for kernel virtio driver to talk with mdev
>> device implementation.
>>
>> Though the series only contains kernel driver support, the goal is to
>> make the transport generic enough to support userspace drivers. This
>> means vhost-mdev[1] could be built on top as well by resuing the
>> transport.
>>
>> A sample driver is also implemented which simulate a virito-net
>> loopback ethernet device on top of vringh + workqueue. This could be
>> used as a reference implementation for real hardware driver.
>>
>> Consider mdev framework only support VFIO device and driver right now,
>> this series also extend it to support other types. This is done
>> through introducing class id to the device and pairing it with
>> id_talbe claimed by the driver. On top, this seris also decouple
> id_table claimed ... this series ...

Let me fix in V3.

Thanks

>
>> device specific parents ops out of the common ones.
>>
>> Pktgen test was done with virito-net + mvnet loop back device.
>>
>> Please review.
>>
>> [1] https://lkml.org/lkml/2019/9/16/869
>>
>> Changes from V1:
>>
>> - move virtio_mdev.c to drivers/virtio
>> - store class_id in mdev_device instead of mdev_parent
>> - store device_ops in mdev_device instead of mdev_parent
>> - reorder the patch, vringh fix comes first
>> - really silent compiling warnings
>> - really switch to use u16 for class_id
>> - uevent and modpost support for mdev class_id
>> - vraious tweaks per comments from Parav
>>
>> Changes from RFC-V2:
>>
>> - silent compile warnings on some specific configuration
>> - use u16 instead u8 for class id
>> - reseve MDEV_ID_VHOST for future vhost-mdev work
>> - introduce "virtio" type for mvnet and make "vhost" type for future
>> work
>> - add entries in MAINTAINER
>> - tweak and typos fixes in commit log
>>
>> Changes from RFC-V1:
>>
>> - rename device id to class id
>> - add docs for class id and device specific ops (device_ops)
>> - split device_ops into seperate headers
>> - drop the mdev_set_dma_ops()
>> - use device_ops to implement the transport API, then it's not a part
>> of UAPI any more
>> - use GFP_ATOMIC in mvnet sample device and other tweaks
>> - set_vring_base/get_vring_base support for mvnet device
>>
>> Jason Wang (8):
>> vringh: fix copy direction of vringh_iov_push_kern()
>> mdev: class id support
>> mdev: bus uevent support
>> modpost: add support for mdev class id
>> mdev: introduce device specific ops
>> mdev: introduce virtio device and its device ops
>> virtio: introduce a mdev based transport
>> docs: sample driver to demonstrate how to implement virtio-mdev
>> framework
>>
>> .../driver-api/vfio-mediated-device.rst | 7 +-
>> MAINTAINERS | 2 +
>> drivers/gpu/drm/i915/gvt/kvmgt.c | 18 +-
>> drivers/s390/cio/vfio_ccw_ops.c | 18 +-
>> drivers/s390/crypto/vfio_ap_ops.c | 14 +-
>> drivers/vfio/mdev/mdev_core.c | 19 +
>> drivers/vfio/mdev/mdev_driver.c | 22 +
>> drivers/vfio/mdev/mdev_private.h | 2 +
>> drivers/vfio/mdev/vfio_mdev.c | 45 +-
>> drivers/vhost/vringh.c | 8 +-
>> drivers/virtio/Kconfig | 7 +
>> drivers/virtio/Makefile | 1 +
>> drivers/virtio/virtio_mdev.c | 417 +++++++++++
>> include/linux/mdev.h | 52 +-
>> include/linux/mod_devicetable.h | 8 +
>> include/linux/vfio_mdev.h | 52 ++
>> include/linux/virtio_mdev.h | 145 ++++
>> samples/Kconfig | 7 +
>> samples/vfio-mdev/Makefile | 1 +
>> samples/vfio-mdev/mbochs.c | 20 +-
>> samples/vfio-mdev/mdpy.c | 20 +-
>> samples/vfio-mdev/mtty.c | 18 +-
>> samples/vfio-mdev/mvnet.c | 692 ++++++++++++++++++
>> scripts/mod/devicetable-offsets.c | 3 +
>> scripts/mod/file2alias.c | 10 +
>> 25 files changed, 1524 insertions(+), 84 deletions(-)
>> create mode 100644 drivers/virtio/virtio_mdev.c
>> create mode 100644 include/linux/vfio_mdev.h
>> create mode 100644 include/linux/virtio_mdev.h
>> create mode 100644 samples/vfio-mdev/mvnet.c
>>
>> --
>> 2.19.1