From 4db97c21ed07a7d4081ed9820599fa36857083d6 Mon Sep 17 00:00:00 2001 From: Nicolin Chen Date: Tue, 5 Nov 2024 12:04:21 -0800 Subject: iommufd/viommu: Add IOMMU_VIOMMU_ALLOC ioctl Add a new ioctl for user space to do a vIOMMU allocation. It must be based on a nesting parent HWPT, so take its refcount. IOMMU driver wanting to support vIOMMUs must define its IOMMU_VIOMMU_TYPE_ in the uAPI header and implement a viommu_alloc op in its iommu_ops. Link: https://patch.msgid.link/r/dc2b8ba9ac935007beff07c1761c31cd097ed780.1730836219.git.nicolinc@nvidia.com Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Signed-off-by: Nicolin Chen Signed-off-by: Jason Gunthorpe --- drivers/iommu/iommufd/Makefile | 3 +- drivers/iommu/iommufd/iommufd_private.h | 3 ++ drivers/iommu/iommufd/main.c | 6 +++ drivers/iommu/iommufd/viommu.c | 81 +++++++++++++++++++++++++++++++++ 4 files changed, 92 insertions(+), 1 deletion(-) create mode 100644 drivers/iommu/iommufd/viommu.c (limited to 'drivers/iommu') diff --git a/drivers/iommu/iommufd/Makefile b/drivers/iommu/iommufd/Makefile index 83df9077063e..cb784da6cddc 100644 --- a/drivers/iommu/iommufd/Makefile +++ b/drivers/iommu/iommufd/Makefile @@ -7,7 +7,8 @@ iommufd-y := \ ioas.o \ main.o \ pages.o \ - vfio_compat.o + vfio_compat.o \ + viommu.o iommufd-$(CONFIG_IOMMUFD_TEST) += selftest.o diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index be347f726fda..a8104d9d4cef 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -506,6 +506,9 @@ static inline int iommufd_hwpt_replace_device(struct iommufd_device *idev, return iommu_group_replace_domain(idev->igroup->group, hwpt->domain); } +int iommufd_viommu_alloc_ioctl(struct iommufd_ucmd *ucmd); +void iommufd_viommu_destroy(struct iommufd_object *obj); + #ifdef CONFIG_IOMMUFD_TEST int iommufd_test(struct iommufd_ucmd *ucmd); void iommufd_selftest_destroy(struct iommufd_object *obj); diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index 30e6c2af3b45..cc514f9bc3e6 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -307,6 +307,7 @@ union ucmd_buffer { struct iommu_ioas_unmap unmap; struct iommu_option option; struct iommu_vfio_ioas vfio_ioas; + struct iommu_viommu_alloc viommu; #ifdef CONFIG_IOMMUFD_TEST struct iommu_test_cmd test; #endif @@ -360,6 +361,8 @@ static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = { val64), IOCTL_OP(IOMMU_VFIO_IOAS, iommufd_vfio_ioas, struct iommu_vfio_ioas, __reserved), + IOCTL_OP(IOMMU_VIOMMU_ALLOC, iommufd_viommu_alloc_ioctl, + struct iommu_viommu_alloc, out_viommu_id), #ifdef CONFIG_IOMMUFD_TEST IOCTL_OP(IOMMU_TEST_CMD, iommufd_test, struct iommu_test_cmd, last), #endif @@ -495,6 +498,9 @@ static const struct iommufd_object_ops iommufd_object_ops[] = { [IOMMUFD_OBJ_FAULT] = { .destroy = iommufd_fault_destroy, }, + [IOMMUFD_OBJ_VIOMMU] = { + .destroy = iommufd_viommu_destroy, + }, #ifdef CONFIG_IOMMUFD_TEST [IOMMUFD_OBJ_SELFTEST] = { .destroy = iommufd_selftest_destroy, diff --git a/drivers/iommu/iommufd/viommu.c b/drivers/iommu/iommufd/viommu.c new file mode 100644 index 000000000000..888239b78667 --- /dev/null +++ b/drivers/iommu/iommufd/viommu.c @@ -0,0 +1,81 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2024, NVIDIA CORPORATION & AFFILIATES + */ +#include "iommufd_private.h" + +void iommufd_viommu_destroy(struct iommufd_object *obj) +{ + struct iommufd_viommu *viommu = + container_of(obj, struct iommufd_viommu, obj); + + if (viommu->ops && viommu->ops->destroy) + viommu->ops->destroy(viommu); + refcount_dec(&viommu->hwpt->common.obj.users); +} + +int iommufd_viommu_alloc_ioctl(struct iommufd_ucmd *ucmd) +{ + struct iommu_viommu_alloc *cmd = ucmd->cmd; + struct iommufd_hwpt_paging *hwpt_paging; + struct iommufd_viommu *viommu; + struct iommufd_device *idev; + const struct iommu_ops *ops; + int rc; + + if (cmd->flags || cmd->type == IOMMU_VIOMMU_TYPE_DEFAULT) + return -EOPNOTSUPP; + + idev = iommufd_get_device(ucmd, cmd->dev_id); + if (IS_ERR(idev)) + return PTR_ERR(idev); + + ops = dev_iommu_ops(idev->dev); + if (!ops->viommu_alloc) { + rc = -EOPNOTSUPP; + goto out_put_idev; + } + + hwpt_paging = iommufd_get_hwpt_paging(ucmd, cmd->hwpt_id); + if (IS_ERR(hwpt_paging)) { + rc = PTR_ERR(hwpt_paging); + goto out_put_idev; + } + + if (!hwpt_paging->nest_parent) { + rc = -EINVAL; + goto out_put_hwpt; + } + + viommu = ops->viommu_alloc(idev->dev, hwpt_paging->common.domain, + ucmd->ictx, cmd->type); + if (IS_ERR(viommu)) { + rc = PTR_ERR(viommu); + goto out_put_hwpt; + } + + viommu->type = cmd->type; + viommu->ictx = ucmd->ictx; + viommu->hwpt = hwpt_paging; + refcount_inc(&viommu->hwpt->common.obj.users); + /* + * It is the most likely case that a physical IOMMU is unpluggable. A + * pluggable IOMMU instance (if exists) is responsible for refcounting + * on its own. + */ + viommu->iommu_dev = __iommu_get_iommu_dev(idev->dev); + + cmd->out_viommu_id = viommu->obj.id; + rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); + if (rc) + goto out_abort; + iommufd_object_finalize(ucmd->ictx, &viommu->obj); + goto out_put_hwpt; + +out_abort: + iommufd_object_abort_and_destroy(ucmd->ictx, &viommu->obj); +out_put_hwpt: + iommufd_put_object(ucmd->ictx, &hwpt_paging->common.obj); +out_put_idev: + iommufd_put_object(ucmd->ictx, &idev->obj); + return rc; +} -- cgit v1.2.3