From 7074d7bd67d495cb3f6fe7c7c96b357a3b9d4ec2 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Mon, 17 Jul 2023 15:12:13 -0300 Subject: [PATCH] iommufd: Add IOMMU_HWPT_ALLOC This allows userspace to manually create HWPTs on IOAS's and then use those HWPTs as inputs to iommufd_device_attach/replace(). Following series will extend this to allow creating iommu_domains with driver specific parameters. Link: https://lore.kernel.org/r/17-v8-6659224517ea+532-iommufd_alloc_jgg@nvidia.com Reviewed-by: Lu Baolu Reviewed-by: Kevin Tian Tested-by: Nicolin Chen Signed-off-by: Jason Gunthorpe --- drivers/iommu/iommufd/hw_pagetable.c | 46 +++++++++++++++++++++++++ drivers/iommu/iommufd/iommufd_private.h | 9 +++++ drivers/iommu/iommufd/main.c | 3 ++ include/uapi/linux/iommufd.h | 26 ++++++++++++++ 4 files changed, 84 insertions(+) diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c index 2087b51d9807..cf2c1504e20d 100644 --- a/drivers/iommu/iommufd/hw_pagetable.c +++ b/drivers/iommu/iommufd/hw_pagetable.c @@ -3,6 +3,7 @@ * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES */ #include +#include #include "iommufd_private.h" @@ -131,3 +132,48 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, iommufd_object_abort_and_destroy(ictx, &hwpt->obj); return ERR_PTR(rc); } + +int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) +{ + struct iommu_hwpt_alloc *cmd = ucmd->cmd; + struct iommufd_hw_pagetable *hwpt; + struct iommufd_device *idev; + struct iommufd_ioas *ioas; + int rc; + + if (cmd->flags || cmd->__reserved) + return -EOPNOTSUPP; + + idev = iommufd_get_device(ucmd, cmd->dev_id); + if (IS_ERR(idev)) + return PTR_ERR(idev); + + ioas = iommufd_get_ioas(ucmd->ictx, cmd->pt_id); + if (IS_ERR(ioas)) { + rc = PTR_ERR(ioas); + goto out_put_idev; + } + + mutex_lock(&ioas->mutex); + hwpt = iommufd_hw_pagetable_alloc(ucmd->ictx, ioas, idev, false); + if (IS_ERR(hwpt)) { + rc = PTR_ERR(hwpt); + goto out_unlock; + } + + cmd->out_hwpt_id = hwpt->obj.id; + rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); + if (rc) + goto out_hwpt; + iommufd_object_finalize(ucmd->ictx, &hwpt->obj); + goto out_unlock; + +out_hwpt: + iommufd_object_abort_and_destroy(ucmd->ictx, &hwpt->obj); +out_unlock: + mutex_unlock(&ioas->mutex); + iommufd_put_object(&ioas->obj); +out_put_idev: + iommufd_put_object(&idev->obj); + return rc; +} diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index 9394f0e6692a..dba730129b8c 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -262,6 +262,7 @@ struct iommufd_hw_pagetable * iommufd_hw_pagetable_detach(struct iommufd_device *idev); void iommufd_hw_pagetable_destroy(struct iommufd_object *obj); void iommufd_hw_pagetable_abort(struct iommufd_object *obj); +int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd); static inline void iommufd_hw_pagetable_put(struct iommufd_ctx *ictx, struct iommufd_hw_pagetable *hwpt) @@ -298,6 +299,14 @@ struct iommufd_device { bool enforce_cache_coherency; }; +static inline struct iommufd_device * +iommufd_get_device(struct iommufd_ucmd *ucmd, u32 id) +{ + return container_of(iommufd_get_object(ucmd->ictx, id, + IOMMUFD_OBJ_DEVICE), + struct iommufd_device, obj); +} + void iommufd_device_destroy(struct iommufd_object *obj); struct iommufd_access { diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index 56cdf3c796a7..94c498b8fdf6 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -265,6 +265,7 @@ static int iommufd_option(struct iommufd_ucmd *ucmd) union ucmd_buffer { struct iommu_destroy destroy; + struct iommu_hwpt_alloc hwpt; struct iommu_ioas_alloc alloc; struct iommu_ioas_allow_iovas allow_iovas; struct iommu_ioas_copy ioas_copy; @@ -296,6 +297,8 @@ struct iommufd_ioctl_op { } static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = { IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct iommu_destroy, id), + IOCTL_OP(IOMMU_HWPT_ALLOC, iommufd_hwpt_alloc, struct iommu_hwpt_alloc, + __reserved), IOCTL_OP(IOMMU_IOAS_ALLOC, iommufd_ioas_alloc_ioctl, struct iommu_ioas_alloc, out_ioas_id), IOCTL_OP(IOMMU_IOAS_ALLOW_IOVAS, iommufd_ioas_allow_iovas, diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h index 98ebba80cfa1..8245c01adca6 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -45,6 +45,7 @@ enum { IOMMUFD_CMD_IOAS_UNMAP, IOMMUFD_CMD_OPTION, IOMMUFD_CMD_VFIO_IOAS, + IOMMUFD_CMD_HWPT_ALLOC, }; /** @@ -344,4 +345,29 @@ struct iommu_vfio_ioas { __u16 __reserved; }; #define IOMMU_VFIO_IOAS _IO(IOMMUFD_TYPE, IOMMUFD_CMD_VFIO_IOAS) + +/** + * struct iommu_hwpt_alloc - ioctl(IOMMU_HWPT_ALLOC) + * @size: sizeof(struct iommu_hwpt_alloc) + * @flags: Must be 0 + * @dev_id: The device to allocate this HWPT for + * @pt_id: The IOAS to connect this HWPT to + * @out_hwpt_id: The ID of the new HWPT + * @__reserved: Must be 0 + * + * Explicitly allocate a hardware page table object. This is the same object + * type that is returned by iommufd_device_attach() and represents the + * underlying iommu driver's iommu_domain kernel object. + * + * A HWPT will be created with the IOVA mappings from the given IOAS. + */ +struct iommu_hwpt_alloc { + __u32 size; + __u32 flags; + __u32 dev_id; + __u32 pt_id; + __u32 out_hwpt_id; + __u32 __reserved; +}; +#define IOMMU_HWPT_ALLOC _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_ALLOC) #endif