In nested translation, the stage-1 page table is user-managed and used by IOMMU hardware, so destroying mappings in the stage-1 page table should be followed with an IOTLB invalidation.
This adds IOMMU_HWPT_INVALIDATE for IOTLB invalidation.
Co-developed-by: Nicolin Chen nicolinc@nvidia.com Signed-off-by: Nicolin Chen nicolinc@nvidia.com Signed-off-by: Yi Liu yi.l.liu@intel.com --- drivers/iommu/iommufd/hw_pagetable.c | 56 +++++++++++++++++++++++++ drivers/iommu/iommufd/iommufd_private.h | 9 ++++ drivers/iommu/iommufd/main.c | 3 ++ include/uapi/linux/iommufd.h | 27 ++++++++++++ 4 files changed, 95 insertions(+)
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c index 64e7cf7142e1..67facca98de1 100644 --- a/drivers/iommu/iommufd/hw_pagetable.c +++ b/drivers/iommu/iommufd/hw_pagetable.c @@ -284,3 +284,59 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) iommufd_put_object(&idev->obj); return rc; } + +/* + * size of page table type specific invalidate_info, indexed by + * enum iommu_hwpt_type. + */ +static const size_t iommufd_hwpt_invalidate_info_size[] = {}; + +int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd) +{ + struct iommu_hwpt_invalidate *cmd = ucmd->cmd; + struct iommufd_hw_pagetable *hwpt; + u64 user_ptr; + u32 user_data_len, klen; + int rc = 0; + + /* + * For a user-managed HWPT, type should not be IOMMU_HWPT_TYPE_DEFAULT. + * data_len should not exceed the size of iommufd_invalidate_buffer. + */ + if (cmd->data_type == IOMMU_HWPT_TYPE_DEFAULT || !cmd->data_len || + cmd->data_type >= ARRAY_SIZE(iommufd_hwpt_invalidate_info_size)) + return -EOPNOTSUPP; + + hwpt = iommufd_get_hwpt(ucmd, cmd->hwpt_id); + if (IS_ERR(hwpt)) + return PTR_ERR(hwpt); + + /* Do not allow any kernel-managed hw_pagetable */ + if (!hwpt->parent) { + rc = -EINVAL; + goto out_put_hwpt; + } + + klen = iommufd_hwpt_invalidate_info_size[cmd->data_type]; + if (!klen) { + rc = -EINVAL; + goto out_put_hwpt; + } + + /* + * Copy the needed fields before reusing the ucmd buffer, this + * avoids memory allocation in this path. + */ + user_ptr = cmd->data_uptr; + user_data_len = cmd->data_len; + + rc = copy_struct_from_user(cmd, klen, + u64_to_user_ptr(user_ptr), user_data_len); + if (rc) + goto out_put_hwpt; + + hwpt->domain->ops->cache_invalidate_user(hwpt->domain, cmd); +out_put_hwpt: + iommufd_put_object(&hwpt->obj); + return rc; +} diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index 182c074eecdc..d879264d1acf 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -265,6 +265,7 @@ struct iommufd_hw_pagetable * iommufd_hw_pagetable_detach(struct iommufd_device *idev); void iommufd_hw_pagetable_destroy(struct iommufd_object *obj); int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd); +int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd);
static inline void iommufd_hw_pagetable_put(struct iommufd_ctx *ictx, struct iommufd_hw_pagetable *hwpt) @@ -276,6 +277,14 @@ static inline void iommufd_hw_pagetable_put(struct iommufd_ctx *ictx, refcount_dec(&hwpt->obj.users); }
+static inline struct iommufd_hw_pagetable * +iommufd_get_hwpt(struct iommufd_ucmd *ucmd, u32 id) +{ + return container_of(iommufd_get_object(ucmd->ictx, id, + IOMMUFD_OBJ_HW_PAGETABLE), + struct iommufd_hw_pagetable, obj); +} + struct iommufd_group { struct kref ref; struct mutex lock; diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index 7ab1e2c638a1..2cf45f65b637 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -263,6 +263,7 @@ union ucmd_buffer { struct iommu_destroy destroy; struct iommu_hwpt_alloc hwpt; struct iommu_hw_info info; + struct iommu_hwpt_invalidate cache; struct iommu_ioas_alloc alloc; struct iommu_ioas_allow_iovas allow_iovas; struct iommu_ioas_copy ioas_copy; @@ -298,6 +299,8 @@ static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = { data_uptr), IOCTL_OP(IOMMU_DEVICE_GET_HW_INFO, iommufd_device_get_hw_info, struct iommu_hw_info, __reserved), + IOCTL_OP(IOMMU_HWPT_INVALIDATE, iommufd_hwpt_invalidate, + struct iommu_hwpt_invalidate, data_uptr), 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 48781ff40a37..d0962c41f8d6 100644 --- a/include/uapi/linux/iommufd.h +++ b/include/uapi/linux/iommufd.h @@ -47,6 +47,7 @@ enum { IOMMUFD_CMD_VFIO_IOAS, IOMMUFD_CMD_HWPT_ALLOC, IOMMUFD_CMD_DEVICE_GET_HW_INFO, + IOMMUFD_CMD_HWPT_INVALIDATE, };
/** @@ -447,4 +448,30 @@ struct iommu_hw_info { __u32 __reserved; }; #define IOMMU_DEVICE_GET_HW_INFO _IO(IOMMUFD_TYPE, IOMMUFD_CMD_DEVICE_GET_HW_INFO) + +/** + * struct iommu_hwpt_invalidate - ioctl(IOMMU_HWPT_INVALIDATE) + * @size: sizeof(struct iommu_hwpt_invalidate) + * @hwpt_id: HWPT ID of target hardware page table for the invalidation + * @data_type: One of enum iommu_hwpt_type + * @data_len: Length of the type specific data + * @data_uptr: User pointer to the type specific data + * + * Invalidate the iommu cache for user-managed page table. Modifications + * on user-managed page table should be followed with this operation to + * sync the IOTLB. This is only needed by user-managed hw_pagetables, so + * the @data_type should never be IOMMU_HWPT_TYPE_DEFAULT. + * + * +==============================+========================================+ + * | @data_type | Data structure in @data_uptr | + * +------------------------------+----------------------------------------+ + */ +struct iommu_hwpt_invalidate { + __u32 size; + __u32 hwpt_id; + __u32 data_type; + __u32 data_len; + __aligned_u64 data_uptr; +}; +#define IOMMU_HWPT_INVALIDATE _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_INVALIDATE) #endif