In nested translation, the stage-1 page table is user-managed but cached by the IOMMU hardware, so an update on present page table entries in the stage-1 page table should be followed with a cache invalidation.
Add an IOMMU_HWPT_INVALIDATE ioctl to support such a cache invalidation. It takes hwpt_id to specify the iommu_domain, and a multi-entry array to support multiple invalidation requests in one ioctl.
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 | 33 +++++++++++++++++++++++++ drivers/iommu/iommufd/iommufd_private.h | 9 +++++++ drivers/iommu/iommufd/main.c | 3 +++ include/uapi/linux/iommufd.h | 29 ++++++++++++++++++++++ 4 files changed, 74 insertions(+)
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c index ab25de149ae6..72c46de1396b 100644 --- a/drivers/iommu/iommufd/hw_pagetable.c +++ b/drivers/iommu/iommufd/hw_pagetable.c @@ -382,3 +382,36 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd) iommufd_put_object(&idev->obj); return rc; } + +int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd) +{ + struct iommu_hwpt_invalidate *cmd = ucmd->cmd; + struct iommu_user_data_array data_array = { + .uptr = u64_to_user_ptr(cmd->reqs_uptr), + .entry_len = cmd->req_len, + .entry_num = cmd->req_num, + }; + struct iommufd_hw_pagetable *hwpt; + int rc = 0; + + if (!cmd->req_len || !cmd->req_num) + return -EOPNOTSUPP; + + hwpt = iommufd_get_hwpt(ucmd, cmd->hwpt_id); + if (IS_ERR(hwpt)) + return PTR_ERR(hwpt); + + if (!hwpt->user_managed) { + rc = -EINVAL; + goto out_put_hwpt; + } + + rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain, &data_array, + &cmd->out_driver_error_code); + cmd->req_num = data_array.entry_num; + if (iommufd_ucmd_respond(ucmd, sizeof(*cmd))) + return -EFAULT; +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 b14f23d3f42e..bdbc8dac2fd8 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -270,6 +270,7 @@ 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); +int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd);
static inline void iommufd_hw_pagetable_put(struct iommufd_ctx *ictx, struct iommufd_hw_pagetable *hwpt) @@ -281,6 +282,14 @@ 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); +} + static inline bool iommufd_hw_pagetable_compare_ioas(struct iommufd_hw_pagetable *old_hwpt, struct iommufd_hw_pagetable *new_hwpt) diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c index e71523cbd0de..d9d82a413105 100644 --- a/drivers/iommu/iommufd/main.c +++ b/drivers/iommu/iommufd/main.c @@ -307,6 +307,7 @@ union ucmd_buffer { struct iommu_destroy destroy; struct iommu_hw_info info; struct iommu_hwpt_alloc hwpt; + struct iommu_hwpt_invalidate cache; struct iommu_ioas_alloc alloc; struct iommu_ioas_allow_iovas allow_iovas; struct iommu_ioas_copy ioas_copy; @@ -342,6 +343,8 @@ static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = { __reserved), IOCTL_OP(IOMMU_HWPT_ALLOC, iommufd_hwpt_alloc, struct iommu_hwpt_alloc, __reserved), + IOCTL_OP(IOMMU_HWPT_INVALIDATE, iommufd_hwpt_invalidate, + struct iommu_hwpt_invalidate, out_driver_error_code), 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 c46b1f772f20..2083a0309a9b 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_GET_HW_INFO, + IOMMUFD_CMD_HWPT_INVALIDATE, };
/** @@ -478,4 +479,32 @@ struct iommu_hw_info { __u32 __reserved; }; #define IOMMU_GET_HW_INFO _IO(IOMMUFD_TYPE, IOMMUFD_CMD_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 cache invalidation + * @reqs_uptr: User pointer to an array having @req_num of cache invalidation + * requests. The request entries in the array are of fixed width + * @req_len, and contain a user data structure for invalidation + * request specific to the given hardware page table. + * @req_len: Length (in bytes) of a request entry in the request array + * @req_num: Input the number of cache invalidation requests in the array. + * Output the number of requests successfully handled by kernel. + * @out_driver_error_code: Report a driver speicifc error code upon failure + * + * Invalidate the iommu cache for user-managed page table. Modifications on a + * user-managed page table should be followed by this operation to sync cache. + * Each ioctl can support one or more cache invalidation requests in the array + * that has a total size of @req_len * @req_num. + */ +struct iommu_hwpt_invalidate { + __u32 size; + __u32 hwpt_id; + __aligned_u64 reqs_uptr; + __u32 req_len; + __u32 req_num; + __u32 out_driver_error_code; +}; +#define IOMMU_HWPT_INVALIDATE _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_INVALIDATE) #endif