From 2fb69c602d57f77483b8dcdd12d17408a09f76fe Mon Sep 17 00:00:00 2001 From: Yi Liu Date: Fri, 21 Mar 2025 10:19:33 -0700 Subject: [PATCH] iommufd: Support pasid attach/replace This extends the below APIs to support PASID. Device drivers to manage pasid attach/replace/detach. int iommufd_device_attach(struct iommufd_device *idev, ioasid_t pasid, u32 *pt_id); int iommufd_device_replace(struct iommufd_device *idev, ioasid_t pasid, u32 *pt_id); void iommufd_device_detach(struct iommufd_device *idev, ioasid_t pasid); The pasid operations share underlying attach/replace/detach infrastructure with the device operations, but still have some different implications: - no reserved region per pasid otherwise SVA architecture is already broken (CPU address space doesn't count device reserved regions); - accordingly no sw_msi trick; Cache coherency enforcement is still applied to pasid operations since it is about memory accesses post page table walking (no matter the walk is per RID or per PASID). Link: https://patch.msgid.link/r/20250321171940.7213-12-yi.l.liu@intel.com Reviewed-by: Jason Gunthorpe Signed-off-by: Kevin Tian Reviewed-by: Nicolin Chen Signed-off-by: Yi Liu Tested-by: Nicolin Chen Signed-off-by: Jason Gunthorpe --- drivers/iommu/iommufd/device.c | 59 ++++++++++++++++++++------------ drivers/iommu/iommufd/selftest.c | 8 ++--- drivers/vfio/iommufd.c | 10 +++--- include/linux/iommufd.h | 9 +++-- 4 files changed, 53 insertions(+), 33 deletions(-) diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index ba21b81e43bc3..4cc6de03f76ee 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -428,9 +428,12 @@ static int iommufd_hwpt_attach_device(struct iommufd_hw_pagetable *hwpt, } handle->idev = idev; - WARN_ON(pasid != IOMMU_NO_PASID); - rc = iommu_attach_group_handle(hwpt->domain, idev->igroup->group, - &handle->handle); + if (pasid == IOMMU_NO_PASID) + rc = iommu_attach_group_handle(hwpt->domain, idev->igroup->group, + &handle->handle); + else + rc = iommu_attach_device_pasid(hwpt->domain, idev->dev, pasid, + &handle->handle); if (rc) goto out_disable_iopf; @@ -464,10 +467,12 @@ static void iommufd_hwpt_detach_device(struct iommufd_hw_pagetable *hwpt, { struct iommufd_attach_handle *handle; - WARN_ON(pasid != IOMMU_NO_PASID); - handle = iommufd_device_get_attach_handle(idev, pasid); - iommu_detach_group_handle(hwpt->domain, idev->igroup->group); + if (pasid == IOMMU_NO_PASID) + iommu_detach_group_handle(hwpt->domain, idev->igroup->group); + else + iommu_detach_device_pasid(hwpt->domain, idev->dev, pasid); + if (hwpt->fault) { iommufd_auto_response_faults(hwpt, handle); iommufd_fault_iopf_disable(idev); @@ -483,8 +488,6 @@ static int iommufd_hwpt_replace_device(struct iommufd_device *idev, struct iommufd_attach_handle *handle, *old_handle; int rc; - WARN_ON(pasid != IOMMU_NO_PASID); - rc = iommufd_hwpt_pasid_compat(hwpt, idev, pasid); if (rc) return rc; @@ -502,8 +505,12 @@ static int iommufd_hwpt_replace_device(struct iommufd_device *idev, } handle->idev = idev; - rc = iommu_replace_group_handle(idev->igroup->group, hwpt->domain, - &handle->handle); + if (pasid == IOMMU_NO_PASID) + rc = iommu_replace_group_handle(idev->igroup->group, + hwpt->domain, &handle->handle); + else + rc = iommu_replace_device_pasid(hwpt->domain, idev->dev, + pasid, &handle->handle); if (rc) goto out_disable_iopf; @@ -904,22 +911,25 @@ out_put_pt_obj: } /** - * iommufd_device_attach - Connect a device to an iommu_domain + * iommufd_device_attach - Connect a device/pasid to an iommu_domain * @idev: device to attach + * @pasid: pasid to attach * @pt_id: Input a IOMMUFD_OBJ_IOAS, or IOMMUFD_OBJ_HWPT_PAGING * Output the IOMMUFD_OBJ_HWPT_PAGING ID * - * This connects the device to an iommu_domain, either automatically or manually - * selected. Once this completes the device could do DMA. + * This connects the device/pasid to an iommu_domain, either automatically + * or manually selected. Once this completes the device could do DMA with + * @pasid. @pasid is IOMMU_NO_PASID if this attach is for no pasid usage. * * The caller should return the resulting pt_id back to userspace. * This function is undone by calling iommufd_device_detach(). */ -int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id) +int iommufd_device_attach(struct iommufd_device *idev, ioasid_t pasid, + u32 *pt_id) { int rc; - rc = iommufd_device_change_pt(idev, IOMMU_NO_PASID, pt_id, + rc = iommufd_device_change_pt(idev, pasid, pt_id, &iommufd_device_do_attach); if (rc) return rc; @@ -934,8 +944,9 @@ int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id) EXPORT_SYMBOL_NS_GPL(iommufd_device_attach, "IOMMUFD"); /** - * iommufd_device_replace - Change the device's iommu_domain + * iommufd_device_replace - Change the device/pasid's iommu_domain * @idev: device to change + * @pasid: pasid to change * @pt_id: Input a IOMMUFD_OBJ_IOAS, or IOMMUFD_OBJ_HWPT_PAGING * Output the IOMMUFD_OBJ_HWPT_PAGING ID * @@ -946,27 +957,31 @@ EXPORT_SYMBOL_NS_GPL(iommufd_device_attach, "IOMMUFD"); * * If it fails then no change is made to the attachment. The iommu driver may * implement this so there is no disruption in translation. This can only be - * called if iommufd_device_attach() has already succeeded. + * called if iommufd_device_attach() has already succeeded. @pasid is + * IOMMU_NO_PASID for no pasid usage. */ -int iommufd_device_replace(struct iommufd_device *idev, u32 *pt_id) +int iommufd_device_replace(struct iommufd_device *idev, ioasid_t pasid, + u32 *pt_id) { - return iommufd_device_change_pt(idev, IOMMU_NO_PASID, pt_id, + return iommufd_device_change_pt(idev, pasid, pt_id, &iommufd_device_do_replace); } EXPORT_SYMBOL_NS_GPL(iommufd_device_replace, "IOMMUFD"); /** - * iommufd_device_detach - Disconnect a device to an iommu_domain + * iommufd_device_detach - Disconnect a device/device to an iommu_domain * @idev: device to detach + * @pasid: pasid to detach * * Undo iommufd_device_attach(). This disconnects the idev from the previously * attached pt_id. The device returns back to a blocked DMA translation. + * @pasid is IOMMU_NO_PASID for no pasid usage. */ -void iommufd_device_detach(struct iommufd_device *idev) +void iommufd_device_detach(struct iommufd_device *idev, ioasid_t pasid) { struct iommufd_hw_pagetable *hwpt; - hwpt = iommufd_hw_pagetable_detach(idev, IOMMU_NO_PASID); + hwpt = iommufd_hw_pagetable_detach(idev, pasid); iommufd_hw_pagetable_put(idev->ictx, hwpt); refcount_dec(&idev->obj.users); } diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c index d55dde28e9bc4..0b3f5cbf242b1 100644 --- a/drivers/iommu/iommufd/selftest.c +++ b/drivers/iommu/iommufd/selftest.c @@ -945,7 +945,7 @@ static int iommufd_test_mock_domain(struct iommufd_ucmd *ucmd, } sobj->idev.idev = idev; - rc = iommufd_device_attach(idev, &pt_id); + rc = iommufd_device_attach(idev, IOMMU_NO_PASID, &pt_id); if (rc) goto out_unbind; @@ -960,7 +960,7 @@ static int iommufd_test_mock_domain(struct iommufd_ucmd *ucmd, return 0; out_detach: - iommufd_device_detach(idev); + iommufd_device_detach(idev, IOMMU_NO_PASID); out_unbind: iommufd_device_unbind(idev); out_mdev: @@ -994,7 +994,7 @@ static int iommufd_test_mock_domain_replace(struct iommufd_ucmd *ucmd, goto out_dev_obj; } - rc = iommufd_device_replace(sobj->idev.idev, &pt_id); + rc = iommufd_device_replace(sobj->idev.idev, IOMMU_NO_PASID, &pt_id); if (rc) goto out_dev_obj; @@ -1655,7 +1655,7 @@ void iommufd_selftest_destroy(struct iommufd_object *obj) switch (sobj->type) { case TYPE_IDEV: - iommufd_device_detach(sobj->idev.idev); + iommufd_device_detach(sobj->idev.idev, IOMMU_NO_PASID); iommufd_device_unbind(sobj->idev.idev); mock_dev_destroy(sobj->idev.mock_dev); break; diff --git a/drivers/vfio/iommufd.c b/drivers/vfio/iommufd.c index 516294fd901be..37e1efa2c7bfe 100644 --- a/drivers/vfio/iommufd.c +++ b/drivers/vfio/iommufd.c @@ -128,7 +128,7 @@ void vfio_iommufd_physical_unbind(struct vfio_device *vdev) lockdep_assert_held(&vdev->dev_set->lock); if (vdev->iommufd_attached) { - iommufd_device_detach(vdev->iommufd_device); + iommufd_device_detach(vdev->iommufd_device, IOMMU_NO_PASID); vdev->iommufd_attached = false; } iommufd_device_unbind(vdev->iommufd_device); @@ -146,9 +146,11 @@ int vfio_iommufd_physical_attach_ioas(struct vfio_device *vdev, u32 *pt_id) return -EINVAL; if (vdev->iommufd_attached) - rc = iommufd_device_replace(vdev->iommufd_device, pt_id); + rc = iommufd_device_replace(vdev->iommufd_device, + IOMMU_NO_PASID, pt_id); else - rc = iommufd_device_attach(vdev->iommufd_device, pt_id); + rc = iommufd_device_attach(vdev->iommufd_device, + IOMMU_NO_PASID, pt_id); if (rc) return rc; vdev->iommufd_attached = true; @@ -163,7 +165,7 @@ void vfio_iommufd_physical_detach_ioas(struct vfio_device *vdev) if (WARN_ON(!vdev->iommufd_device) || !vdev->iommufd_attached) return; - iommufd_device_detach(vdev->iommufd_device); + iommufd_device_detach(vdev->iommufd_device, IOMMU_NO_PASID); vdev->iommufd_attached = false; } EXPORT_SYMBOL_GPL(vfio_iommufd_physical_detach_ioas); diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h index 60eff9272551d..34b6e6ca4bfa0 100644 --- a/include/linux/iommufd.h +++ b/include/linux/iommufd.h @@ -8,6 +8,7 @@ #include #include +#include #include #include #include @@ -54,9 +55,11 @@ struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx, struct device *dev, u32 *id); void iommufd_device_unbind(struct iommufd_device *idev); -int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id); -int iommufd_device_replace(struct iommufd_device *idev, u32 *pt_id); -void iommufd_device_detach(struct iommufd_device *idev); +int iommufd_device_attach(struct iommufd_device *idev, ioasid_t pasid, + u32 *pt_id); +int iommufd_device_replace(struct iommufd_device *idev, ioasid_t pasid, + u32 *pt_id); +void iommufd_device_detach(struct iommufd_device *idev, ioasid_t pasid); struct iommufd_ctx *iommufd_device_to_ictx(struct iommufd_device *idev); u32 iommufd_device_to_id(struct iommufd_device *idev); -- 2.39.5