On Sun, Oct 22, 2023 at 11:20:31AM +0300, Yishai Hadas wrote: > On 17/10/2023 16:42, Yishai Hadas wrote: > > 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 6 patches are in the virtio area and handle the below: > > - Fix common config map for modern device as was reported by Michael Tsirkin. > > - Introduce the admin virtqueue infrastcture. > > - Expose the layout of the commands that should be used for > > supporting the legacy access. > > - Expose APIs to enable upper layers as of vfio, net, etc > > to execute admin commands. > > > > The above follows the virtio spec that was lastly accepted in that area > > [1]. > > > > The last 3 patches are in the vfio area and handle the below: > > - Expose some APIs from vfio/pci to be used by the vfio/virtio driver. > > - 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 > > > > Changes from V0: https://www.spinics.net/lists/linux-virtualization/msg63802.html > > > > Virtio: > > - Fix the common config map size issue that was reported by Michael > > Tsirkin. > > - Do not use vp_dev->vqs[] array upon vp_del_vqs() as was asked by > > Michael, instead skip the AQ specifically. > > - Move admin vq implementation into virtio_pci_modern.c as was asked by > > Michael. > > - Rename structure virtio_avq to virtio_pci_admin_vq and some extra > > corresponding renames. > > - Remove exported symbols virtio_pci_vf_get_pf_dev(), > > virtio_admin_cmd_exec() as now callers are local to the module. > > - Handle inflight commands as part of the device reset flow. > > - Introduce APIs per admin command in virtio-pci as was asked by Michael. > > > > Vfio: > > - Change to use EXPORT_SYMBOL_GPL instead of EXPORT_SYMBOL for > > vfio_pci_core_setup_barmap() and vfio_pci_iowrite#xxx() as pointed by > > Alex. > > - Drop the intermediate patch which prepares the commands and calls the > > generic virtio admin command API (i.e. virtio_admin_cmd_exec()). > > - Instead, call directly to the new APIs per admin command that are > > exported from Virtio - based on Michael's request. > > - Enable only virtio-net as part of the pci_device_id table to enforce > > upon binding only what is supported as suggested by Alex. > > - Add support for byte-wise access (read/write) over the device config > > region as was asked by Alex. > > - Consider whether MSIX is practically enabled/disabled to choose the > > right opcode upon issuing read/write admin command, as mentioned > > by Michael. > > - Move to use VIRTIO_PCI_CONFIG_OFF instead of adding some new defines > > as was suggested by Michael. > > - Set the '.close_device' op to vfio_pci_core_close_device() as was > > pointed by Alex. > > - Adapt to Vfio multi-line comment style in a few places. > > - Add virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx in the MAINTAINERS file > > to be CCed for the new driver as was suggested by Jason. > > > > Yishai > > > > Feng Liu (5): > > virtio-pci: Fix common config map for modern device > > virtio: Define feature bit for administration virtqueue > > virtio-pci: Introduce admin virtqueue > > virtio-pci: Introduce admin command sending function > > virtio-pci: Introduce admin commands > > > > Yishai Hadas (4): > > virtio-pci: Introduce APIs to execute legacy IO admin commands > > vfio/pci: Expose vfio_pci_core_setup_barmap() > > vfio/pci: Expose vfio_pci_iowrite/read##size() > > vfio/virtio: Introduce a vfio driver over virtio devices > > > > MAINTAINERS | 7 + > > 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/main.c | 577 +++++++++++++++++++++++++ > > drivers/virtio/virtio.c | 37 +- > > drivers/virtio/virtio_pci_common.c | 14 + > > drivers/virtio/virtio_pci_common.h | 20 +- > > drivers/virtio/virtio_pci_modern.c | 441 ++++++++++++++++++- > > drivers/virtio/virtio_pci_modern_dev.c | 24 +- > > include/linux/vfio_pci_core.h | 20 + > > include/linux/virtio.h | 8 + > > include/linux/virtio_config.h | 4 + > > include/linux/virtio_pci_admin.h | 18 + > > include/linux/virtio_pci_modern.h | 5 + > > include/uapi/linux/virtio_config.h | 8 +- > > include/uapi/linux/virtio_pci.h | 66 +++ > > 20 files changed, 1295 insertions(+), 40 deletions(-) > > create mode 100644 drivers/vfio/pci/virtio/Kconfig > > create mode 100644 drivers/vfio/pci/virtio/Makefile > > create mode 100644 drivers/vfio/pci/virtio/main.c > > create mode 100644 include/linux/virtio_pci_admin.h > > > Hi Michael, > > Did you have the chance to review the virtio part of that series ? Not yet, will take a couple more days. > IMO, we addressed all your notes on V0, I would be happy to get your > feedback on V1 before sending V2. > > In my TO-DO list for V2, have for now the below minor items. > Virtio: > Patch #6: Fix a krobot note where it needs to include the H file as part of > the export symbols C file. > Vfio: > #patch #9: Rename the 'ops' variable to drop the 'acc' and potentially some > rename in the description of the module with regards to 'family'. > > Alex, > Are you fine to leave the provisioning of the VF including the control of > its transitional capability in the device hands as was suggested by Jason ? > Any specific recommendation following the discussion in the ML, for the > 'family' note ? > > Once I'll have the above feedback I may prepare and send V2. > > Yishai
