> -----Original Message----- > From: Liu, Yi L <yi.l.liu@xxxxxxxxx> > Subject: [PATCH v5 00/10] Enhance vfio PCI hot reset for vfio cdev device > > VFIO_DEVICE_PCI_HOT_RESET requires user to pass an array of group fds to > prove that it owns all devices affected by resetting the calling device. While > for cdev devices, user can use an iommufd-based ownership checking model > and invoke VFIO_DEVICE_PCI_HOT_RESET with a zero-length fd array. > > This series first creates iommufd_access for noiommu devices to fill the gap > for adding iommufd-based ownership checking model, then extends > VFIO_DEVICE_GET_PCI_HOT_RESET_INFO to check ownership and return > the check result and the devid of affected devices to user. In the end, > extends the VFIO_DEVICE_PCI_HOT_RESET to accept zero-length fd array for > hot-reset with cdev devices. > > The new hot reset method and updated _INFO ioctl are tested with the > below qemu: > > https://github.com/yiliu1765/qemu/tree/iommufd_rfcv4.mig.reset.v4_var3 > (requires to test with the cdev kernel) > > Change log: > > v5: > - Drop patch 01 of v4 (Alex) > - Create noiommu_access for noiommu devices (Jason) > - Reserve all negative iommufd IDs, hence VFIO can encode negative > values (Jason) > - Make vfio_iommufd_physical_devid() return -EINVAL if it's not called > with a physical device or a noiommu device. > - Add vfio_find_device_in_devset() in vfio_main.c (Alex) > - Add iommufd_ctx_has_group() to replace > vfio_devset_iommufd_has_group(). > Reason: vfio_devset_iommufd_has_group() only loops the devices within > the given devset to check the iommufd an iommu_group, but an > iommu_group > can span into multiple devsets. So if failed to find the group in a > devset doesn't mean the group is not owned by the iommufd. So here > either > needs to search all the devsets or add an iommufd API to check it. It > appears an iommufd API makes more sense. > - Adopt suggestions from Alex on patch 08 and 09 of v4, refine the hot-reset > uapi description and minor tweaks > - Use bitfields for bool members (Alex) > > v4: https://lore.kernel.org/kvm/20230426145419.450922-1-yi.l.liu@xxxxxxxxx/ > - Rename the patch series subject > - Patch 01 is moved from the cdev series > - Patch 02, 06 are new per review comments in v3 > - Patch 03/04/05/07/08/09 are from v3 with updates > > v3: https://lore.kernel.org/kvm/20230401144429.88673-1-yi.l.liu@xxxxxxxxx/ > - Remove the new _INFO ioctl of v2, extend the existing _INFO ioctl to > report devid (Alex) > - Add r-b from Jason > - Add t-b from Terrence Xu and Yanting Jiang (mainly regression test) > > v2: https://lore.kernel.org/kvm/20230327093458.44939-1-yi.l.liu@xxxxxxxxx/ > - Split the patch 03 of v1 to be 03, 04 and 05 of v2 (Jaon) > - Add r-b from Kevin and Jason > - Add patch 10 to introduce a new _INFO ioctl for the usage of device > fd passing usage in cdev path (Jason, Alex) > > v1: https://lore.kernel.org/kvm/20230316124156.12064-1-yi.l.liu@xxxxxxxxx/ > > Regards, > Yi Liu > > Yi Liu (10): > vfio-iommufd: Create iommufd_access for noiommu devices > vfio/pci: Update comment around group_fd get in > vfio_pci_ioctl_pci_hot_reset() > vfio/pci: Move the existing hot reset logic to be a helper > vfio: Mark cdev usage in vfio_device > iommufd: Reserve all negative IDs in the iommufd xarray > vfio-iommufd: Add helper to retrieve iommufd_ctx and devid for > vfio_device > vfio: Add helper to search vfio_device in a dev_set > iommufd: Add iommufd_ctx_has_group() > vfio/pci: Extend VFIO_DEVICE_GET_PCI_HOT_RESET_INFO for vfio device > cdev > vfio/pci: Allow passing zero-length fd array in > VFIO_DEVICE_PCI_HOT_RESET > > drivers/iommu/iommufd/device.c | 53 +++++++++ > drivers/iommu/iommufd/main.c | 2 +- > drivers/vfio/iommufd.c | 63 ++++++++++- > drivers/vfio/pci/vfio_pci_core.c | 184 ++++++++++++++++++++++++------- > drivers/vfio/vfio_main.c | 15 +++ > include/linux/iommufd.h | 14 +++ > include/linux/vfio.h | 23 ++++ > include/uapi/linux/vfio.h | 60 +++++++++- > 8 files changed, 368 insertions(+), 46 deletions(-) > > -- > 2.34.1 The new uapi works fine. Tested GVT-g / GVT-d VFIO legacy mode / compat mode / cdev mode, including negative tests. No regression be introduced. Tested-by: Terrence Xu <terrence.xu@xxxxxxxxx>
