kernel/linux.git/include/linux/iommufd.h, branch v6.6.131

iommufd: Add iommufd_access_replace() API

2023-07-28T16:31:24+00:00

Taking advantage of the new iommufd_access_change_ioas_id helper, add an iommufd_access_replace() API for the VFIO emulated pathway to use. Link: https://lore.kernel.org/r/a3267b924fd5f45e0d3a1dd13a9237e923563862.1690523699.git.nicolinc@nvidia.com Suggested-by: Jason Gunthorpe Reviewed-by: Kevin Tian Signed-off-by: Nicolin Chen Reviewed-by: Jason Gunthorpe Signed-off-by: Jason Gunthorpe

iommufd/selftest: Test iommufd_device_replace()

2023-07-26T13:20:26+00:00

Allow the selftest to call the function on the mock idev, add some tests to exercise it. Link: https://lore.kernel.org/r/16-v8-6659224517ea+532-iommufd_alloc_jgg@nvidia.com Reviewed-by: Kevin Tian Tested-by: Nicolin Chen Signed-off-by: Nicolin Chen Signed-off-by: Yi Liu Signed-off-by: Jason Gunthorpe

iommufd: Add iommufd_ctx_from_fd()

2023-07-25T16:19:53+00:00

It's common to get a reference to the iommufd context from a given file descriptor. So adds an API for it. Existing users of this API are compiled only when IOMMUFD is enabled, so no need to have a stub for the IOMMUFD disabled case. Tested-by: Yanting Jiang Reviewed-by: Jason Gunthorpe Signed-off-by: Yi Liu Link: https://lore.kernel.org/r/20230718135551.6592-21-yi.l.liu@intel.com Signed-off-by: Alex Williamson

iommufd/device: Add iommufd_access_detach() API

2023-07-25T16:19:14+00:00

Previously, the detach routine is only done by the destroy(). And it was called by vfio_iommufd_emulated_unbind() when the device runs close(), so all the mappings in iopt were cleaned in that setup, when the call trace reaches this detach() routine. Now, there's a need of a detach uAPI, meaning that it does not only need a new iommufd_access_detach() API, but also requires access->ops->unmap() call as a cleanup. So add one. However, leaving that unprotected can introduce some potential of a race condition during the pin_/unpin_pages() call, where access->ioas->iopt is getting referenced. So, add an ioas_lock to protect the context of iopt referencings. Also, to allow the iommufd_access_unpin_pages() callback to happen via this unmap() call, add an ioas_unpin pointer, so the unpin routine won't be affected by the "access->ioas = NULL" trick. Reviewed-by: Kevin Tian Reviewed-by: Jason Gunthorpe Tested-by: Terrence Xu Tested-by: Nicolin Chen Tested-by: Matthew Rosato Tested-by: Yanting Jiang Tested-by: Shameer Kolothum Tested-by: Zhenzhong Duan Signed-off-by: Nicolin Chen Signed-off-by: Yi Liu Link: https://lore.kernel.org/r/20230718135551.6592-15-yi.l.liu@intel.com Signed-off-by: Alex Williamson

iommufd: Add helper to retrieve iommufd_ctx and devid

2023-07-25T16:17:55+00:00

This is needed by the vfio-pci driver to report affected devices in the hot-reset for a given device. Reviewed-by: Jason Gunthorpe Tested-by: Yanting Jiang Tested-by: Terrence Xu Tested-by: Zhenzhong Duan Signed-off-by: Yi Liu Link: https://lore.kernel.org/r/20230718105542.4138-6-yi.l.liu@intel.com Signed-off-by: Alex Williamson

iommufd: Add iommufd_ctx_has_group()

2023-07-25T16:17:52+00:00

This adds the helper to check if any device within the given iommu_group has been bound with the iommufd_ctx. This is helpful for the checking on device ownership for the devices which have not been bound but cannot be bound to any other iommufd_ctx as the iommu_group has been bound. Reviewed-by: Jason Gunthorpe Tested-by: Yanting Jiang Tested-by: Terrence Xu Tested-by: Zhenzhong Duan Signed-off-by: Yi Liu Link: https://lore.kernel.org/r/20230718105542.4138-5-yi.l.liu@intel.com Signed-off-by: Alex Williamson

vfio-iommufd: Make vfio_iommufd_emulated_bind() return iommufd_access ID

2023-03-31T16:43:32+00:00

vfio device cdev needs to return iommufd_access ID to userspace if bind_iommufd succeeds. Link: https://lore.kernel.org/r/20230327093351.44505-5-yi.l.liu@intel.com Reviewed-by: Kevin Tian Reviewed-by: Jason Gunthorpe Tested-by: Terrence Xu Tested-by: Nicolin Chen Signed-off-by: Yi Liu Acked-by: Alex Williamson Signed-off-by: Jason Gunthorpe

iommufd: Create access in vfio_iommufd_emulated_bind()

2023-03-31T16:43:31+00:00

There are needs to created iommufd_access prior to have an IOAS and set IOAS later. Like the vfio device cdev needs to have an iommufd object to represent the bond (iommufd_access) and IOAS replacement. Moves the iommufd_access_create() call into vfio_iommufd_emulated_bind(), making it symmetric with the __vfio_iommufd_access_destroy() call in the vfio_iommufd_emulated_unbind(). This means an access is created/destroyed by the bind()/unbind(), and the vfio_iommufd_emulated_attach_ioas() only updates the access->ioas pointer. Since vfio_iommufd_emulated_bind() does not provide ioas_id, drop it from the argument list of iommufd_access_create(). Instead, add a new access API iommufd_access_attach() to set the access->ioas pointer. Also, set vdev->iommufd_attached accordingly, similar to the physical pathway. Link: https://lore.kernel.org/r/20230327093351.44505-3-yi.l.liu@intel.com Reviewed-by: Kevin Tian Reviewed-by: Jason Gunthorpe Tested-by: Terrence Xu Tested-by: Nicolin Chen Signed-off-by: Nicolin Chen Signed-off-by: Yi Liu Acked-by: Alex Williamson Signed-off-by: Jason Gunthorpe

vfio: Support VFIO_NOIOMMU with iommufd

2023-02-03T19:45:23+00:00

Add a small amount of emulation to vfio_compat to accept the SET_IOMMU to VFIO_NOIOMMU_IOMMU and have vfio just ignore iommufd if it is working on a no-iommu enabled device. Move the enable_unsafe_noiommu_mode module out of container.c into vfio_main.c so that it is always available even if VFIO_CONTAINER=n. This passes Alex's mini-test: https://github.com/awilliam/tests/blob/master/vfio-noiommu-pci-device-open.c Link: https://lore.kernel.org/r/0-v3-480cd64a16f7+1ad0-iommufd_noiommu_jgg@nvidia.com Reviewed-by: Kevin Tian Acked-by: Alex Williamson Signed-off-by: Jason Gunthorpe

iommufd: Add kernel support for testing iommufd

2022-12-01T00:16:49+00:00

Provide a mock kernel module for the iommu_domain that allows it to run without any HW and the mocking provides a way to directly validate that the PFNs loaded into the iommu_domain are correct. This exposes the access kAPI toward userspace to allow userspace to explore the functionality of pages.c and io_pagetable.c The mock also simulates the rare case of PAGE_SIZE > iommu page size as the mock will operate at a 2K iommu page size. This allows exercising all of the calculations to support this mismatch. This is also intended to support syzkaller exploring the same space. However, it is an unusually invasive config option to enable all of this. The config option should not be enabled in a production kernel. Link: https://lore.kernel.org/r/16-v6-a196d26f289e+11787-iommufd_jgg@nvidia.com Tested-by: Matthew Rosato # s390 Tested-by: Eric Auger # aarch64 Signed-off-by: Jason Gunthorpe