RE: [PATCH V1 vfio 0/9] Introduce a vfio driver over virtio devices
> From: Jason Gunthorpe > Sent: Monday, October 23, 2023 11:43 PM > > On Mon, Oct 23, 2023 at 09:33:23AM -0600, Alex Williamson wrote: > > > > 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 ? > > > > If this is the standard we're going to follow, ie. profiling of a > > device is expected to occur prior to the probe of the vfio-pci variant > > driver, then we should get the out-of-tree NVIDIA vGPU driver on board > > with this too. > > Those GPU drivers are using mdev not vfio-pci.. > > mdev doesn't have a way in its uapi to configure the mdev before it is > created. > > I'm hopeful that the SIOV work will develop something better because > we clearly need it for the general use cases of SIOV beyond VFIO. > The internal idxd driver version which I looked at last time leaves provisioning via idxd's own config interface. sure let's brainstorm what'd be (if possible) a general provisioning framework after it's sent out for review. ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Re: [PATCH V1 vfio 0/9] Introduce a vfio driver over virtio devices
On Mon, 23 Oct 2023 13:20:43 -0300 Jason Gunthorpe wrote: > On Mon, Oct 23, 2023 at 10:09:13AM -0600, Alex Williamson wrote: > > On Mon, 23 Oct 2023 12:42:57 -0300 > > Jason Gunthorpe wrote: > > > > > On Mon, Oct 23, 2023 at 09:33:23AM -0600, Alex Williamson wrote: > > > > > > > > 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 ? > > > > > > > > If this is the standard we're going to follow, ie. profiling of a > > > > device is expected to occur prior to the probe of the vfio-pci variant > > > > driver, then we should get the out-of-tree NVIDIA vGPU driver on board > > > > with this too. > > > > > > Those GPU drivers are using mdev not vfio-pci.. > > > > The SR-IOV mdev vGPUs rely on the IOMMU backing device support which > > was removed from upstream. > > It wasn't, but it changed forms. > > mdev is a sysfs framework for managing lifecycle with GUIDs only. > > The thing using mdev can call vfio_register_emulated_iommu_dev() or > vfio_register_group_dev(). > > It doesn't matter to the mdev stuff. > > The thing using mdev is responsible to get the struct device to pass > to vfio_register_group_dev() Are we describing what can be done (possibly limited to out-of-tree drivers) or what should be done and would be accepted upstream? I'm under the impression that mdev has been redefined to be more narrowly focused for emulated IOMMU devices and that devices based around a PCI VF should be making use of a vfio-pci variant driver. Are you suggesting it's the vendor's choice based on whether they want the mdev lifecycle support? We've defined certain aspects of the vfio-mdev interface as only available for emulated IOMMU devices, ex. page pinning. Thanks, Alex ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Re: [PATCH V1 vfio 0/9] Introduce a vfio driver over virtio devices
On Mon, 23 Oct 2023 12:42:57 -0300 Jason Gunthorpe wrote: > On Mon, Oct 23, 2023 at 09:33:23AM -0600, Alex Williamson wrote: > > > > 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 ? > > > > If this is the standard we're going to follow, ie. profiling of a > > device is expected to occur prior to the probe of the vfio-pci variant > > driver, then we should get the out-of-tree NVIDIA vGPU driver on board > > with this too. > > Those GPU drivers are using mdev not vfio-pci.. The SR-IOV mdev vGPUs rely on the IOMMU backing device support which was removed from upstream. They only exist in the mdev form on downstreams which have retained this interface for compatibility and continuity. I'm not aware of any other means by which the SR-IOV RID can be used in the mdev model, therefore only the pre-SR-IOV GPUs should continue to use the mdev interface. > mdev doesn't have a way in its uapi to configure the mdev before it is > created. Of course. Thanks, Alex ___ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
Re: [PATCH V1 vfio 0/9] Introduce a vfio driver over virtio devices
On Sun, 22 Oct 2023 11:20:31 +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@lists.linux-foundation.org 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
Re: [PATCH V1 vfio 0/9] Introduce a vfio driver over virtio devices
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@lists.linux-foundation.org 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
Re: [PATCH V1 vfio 0/9] Introduce a vfio driver over virtio devices
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@lists.linux-foundation.org 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 +-
