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Diffstat (limited to 'include/linux/iommufd.h')
| -rw-r--r-- | include/linux/iommufd.h | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h new file mode 100644 index 000000000000..6e7efe83bc5d --- /dev/null +++ b/include/linux/iommufd.h @@ -0,0 +1,400 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2021 Intel Corporation + * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES + */ +#ifndef __LINUX_IOMMUFD_H +#define __LINUX_IOMMUFD_H + +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/iommu.h> +#include <linux/refcount.h> +#include <linux/types.h> +#include <linux/xarray.h> +#include <uapi/linux/iommufd.h> + +struct device; +struct file; +struct iommu_group; +struct iommu_user_data; +struct iommu_user_data_array; +struct iommufd_access; +struct iommufd_ctx; +struct iommufd_device; +struct iommufd_viommu_ops; +struct page; + +enum iommufd_object_type { + IOMMUFD_OBJ_NONE, + IOMMUFD_OBJ_ANY = IOMMUFD_OBJ_NONE, + IOMMUFD_OBJ_DEVICE, + IOMMUFD_OBJ_HWPT_PAGING, + IOMMUFD_OBJ_HWPT_NESTED, + IOMMUFD_OBJ_IOAS, + IOMMUFD_OBJ_ACCESS, + IOMMUFD_OBJ_FAULT, + IOMMUFD_OBJ_VIOMMU, + IOMMUFD_OBJ_VDEVICE, + IOMMUFD_OBJ_VEVENTQ, + IOMMUFD_OBJ_HW_QUEUE, +#ifdef CONFIG_IOMMUFD_TEST + IOMMUFD_OBJ_SELFTEST, +#endif + IOMMUFD_OBJ_MAX, +}; + +/* Base struct for all objects with a userspace ID handle. */ +struct iommufd_object { + /* + * Destroy will sleep and wait for wait_cnt to go to zero. This allows + * concurrent users of the ID to reliably avoid causing a spurious + * destroy failure. Incrementing this count should either be short + * lived or be revoked and blocked during pre_destroy(). + */ + refcount_t wait_cnt; + refcount_t users; + enum iommufd_object_type type; + unsigned int id; +}; + +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, 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); + +struct iommufd_access_ops { + u8 needs_pin_pages : 1; + void (*unmap)(void *data, unsigned long iova, unsigned long length); +}; + +enum { + IOMMUFD_ACCESS_RW_READ = 0, + IOMMUFD_ACCESS_RW_WRITE = 1 << 0, + /* Set if the caller is in a kthread then rw will use kthread_use_mm() */ + IOMMUFD_ACCESS_RW_KTHREAD = 1 << 1, + + /* Only for use by selftest */ + __IOMMUFD_ACCESS_RW_SLOW_PATH = 1 << 2, +}; + +struct iommufd_access * +iommufd_access_create(struct iommufd_ctx *ictx, + const struct iommufd_access_ops *ops, void *data, u32 *id); +void iommufd_access_destroy(struct iommufd_access *access); +int iommufd_access_attach(struct iommufd_access *access, u32 ioas_id); +int iommufd_access_replace(struct iommufd_access *access, u32 ioas_id); +void iommufd_access_detach(struct iommufd_access *access); + +void iommufd_ctx_get(struct iommufd_ctx *ictx); + +struct iommufd_viommu { + struct iommufd_object obj; + struct iommufd_ctx *ictx; + struct iommu_device *iommu_dev; + struct iommufd_hwpt_paging *hwpt; + + const struct iommufd_viommu_ops *ops; + + struct xarray vdevs; + struct list_head veventqs; + struct rw_semaphore veventqs_rwsem; + + enum iommu_viommu_type type; +}; + +struct iommufd_vdevice { + struct iommufd_object obj; + struct iommufd_viommu *viommu; + struct iommufd_device *idev; + + /* + * Virtual device ID per vIOMMU, e.g. vSID of ARM SMMUv3, vDeviceID of + * AMD IOMMU, and vRID of Intel VT-d + */ + u64 virt_id; + + /* Clean up all driver-specific parts of an iommufd_vdevice */ + void (*destroy)(struct iommufd_vdevice *vdev); +}; + +struct iommufd_hw_queue { + struct iommufd_object obj; + struct iommufd_viommu *viommu; + struct iommufd_access *access; + + u64 base_addr; /* in guest physical address space */ + size_t length; + + enum iommu_hw_queue_type type; + + /* Clean up all driver-specific parts of an iommufd_hw_queue */ + void (*destroy)(struct iommufd_hw_queue *hw_queue); +}; + +/** + * struct iommufd_viommu_ops - vIOMMU specific operations + * @destroy: Clean up all driver-specific parts of an iommufd_viommu. The memory + * of the vIOMMU will be free-ed by iommufd core after calling this op + * @alloc_domain_nested: Allocate a IOMMU_DOMAIN_NESTED on a vIOMMU that holds a + * nesting parent domain (IOMMU_DOMAIN_PAGING). @user_data + * must be defined in include/uapi/linux/iommufd.h. + * It must fully initialize the new iommu_domain before + * returning. Upon failure, ERR_PTR must be returned. + * @cache_invalidate: Flush hardware cache used by a vIOMMU. It can be used for + * any IOMMU hardware specific cache: TLB and device cache. + * The @array passes in the cache invalidation requests, in + * form of a driver data structure. A driver must update the + * array->entry_num to report the number of handled requests. + * The data structure of the array entry must be defined in + * include/uapi/linux/iommufd.h + * @vdevice_size: Size of the driver-defined vDEVICE structure per this vIOMMU + * @vdevice_init: Initialize the driver-level structure of a vDEVICE object, or + * related HW procedure. @vdev is already initialized by iommufd + * core: vdev->dev and vdev->viommu pointers; vdev->id carries a + * per-vIOMMU virtual ID (refer to struct iommu_vdevice_alloc in + * include/uapi/linux/iommufd.h) + * If driver has a deinit function to revert what vdevice_init op + * does, it should set it to the @vdev->destroy function pointer + * @get_hw_queue_size: Get the size of a driver-defined HW queue structure for a + * given @viommu corresponding to @queue_type. Driver should + * return 0 if HW queue aren't supported accordingly. It is + * required for driver to use the HW_QUEUE_STRUCT_SIZE macro + * to sanitize the driver-level HW queue structure related + * to the core one + * @hw_queue_init_phys: Initialize the driver-level structure of a HW queue that + * is initialized with its core-level structure that holds + * all the info about a guest queue memory. + * Driver providing this op indicates that HW accesses the + * guest queue memory via physical addresses. + * @index carries the logical HW QUEUE ID per vIOMMU in a + * guest VM, for a multi-queue model. @base_addr_pa carries + * the physical location of the guest queue + * If driver has a deinit function to revert what this op + * does, it should set it to the @hw_queue->destroy pointer + */ +struct iommufd_viommu_ops { + void (*destroy)(struct iommufd_viommu *viommu); + struct iommu_domain *(*alloc_domain_nested)( + struct iommufd_viommu *viommu, u32 flags, + const struct iommu_user_data *user_data); + int (*cache_invalidate)(struct iommufd_viommu *viommu, + struct iommu_user_data_array *array); + const size_t vdevice_size; + int (*vdevice_init)(struct iommufd_vdevice *vdev); + size_t (*get_hw_queue_size)(struct iommufd_viommu *viommu, + enum iommu_hw_queue_type queue_type); + /* AMD's HW will add hw_queue_init simply using @hw_queue->base_addr */ + int (*hw_queue_init_phys)(struct iommufd_hw_queue *hw_queue, u32 index, + phys_addr_t base_addr_pa); +}; + +#if IS_ENABLED(CONFIG_IOMMUFD) +struct iommufd_ctx *iommufd_ctx_from_file(struct file *file); +struct iommufd_ctx *iommufd_ctx_from_fd(int fd); +void iommufd_ctx_put(struct iommufd_ctx *ictx); +bool iommufd_ctx_has_group(struct iommufd_ctx *ictx, struct iommu_group *group); + +int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova, + unsigned long length, struct page **out_pages, + unsigned int flags); +void iommufd_access_unpin_pages(struct iommufd_access *access, + unsigned long iova, unsigned long length); +int iommufd_access_rw(struct iommufd_access *access, unsigned long iova, + void *data, size_t len, unsigned int flags); +int iommufd_vfio_compat_ioas_get_id(struct iommufd_ctx *ictx, u32 *out_ioas_id); +int iommufd_vfio_compat_ioas_create(struct iommufd_ctx *ictx); +int iommufd_vfio_compat_set_no_iommu(struct iommufd_ctx *ictx); +#else /* !CONFIG_IOMMUFD */ +static inline struct iommufd_ctx *iommufd_ctx_from_file(struct file *file) +{ + return ERR_PTR(-EOPNOTSUPP); +} + +static inline void iommufd_ctx_put(struct iommufd_ctx *ictx) +{ +} + +static inline int iommufd_access_pin_pages(struct iommufd_access *access, + unsigned long iova, + unsigned long length, + struct page **out_pages, + unsigned int flags) +{ + return -EOPNOTSUPP; +} + +static inline void iommufd_access_unpin_pages(struct iommufd_access *access, + unsigned long iova, + unsigned long length) +{ +} + +static inline int iommufd_access_rw(struct iommufd_access *access, + unsigned long iova, void *data, size_t len, + unsigned int flags) +{ + return -EOPNOTSUPP; +} + +static inline int iommufd_vfio_compat_ioas_create(struct iommufd_ctx *ictx) +{ + return -EOPNOTSUPP; +} + +static inline int iommufd_vfio_compat_set_no_iommu(struct iommufd_ctx *ictx) +{ + return -EOPNOTSUPP; +} +#endif /* CONFIG_IOMMUFD */ + +#if IS_ENABLED(CONFIG_IOMMUFD_DRIVER_CORE) +int _iommufd_object_depend(struct iommufd_object *obj_dependent, + struct iommufd_object *obj_depended); +void _iommufd_object_undepend(struct iommufd_object *obj_dependent, + struct iommufd_object *obj_depended); +int _iommufd_alloc_mmap(struct iommufd_ctx *ictx, struct iommufd_object *owner, + phys_addr_t mmio_addr, size_t length, + unsigned long *offset); +void _iommufd_destroy_mmap(struct iommufd_ctx *ictx, + struct iommufd_object *owner, unsigned long offset); +struct device *iommufd_vdevice_to_device(struct iommufd_vdevice *vdev); +struct device *iommufd_viommu_find_dev(struct iommufd_viommu *viommu, + unsigned long vdev_id); +int iommufd_viommu_get_vdev_id(struct iommufd_viommu *viommu, + struct device *dev, unsigned long *vdev_id); +int iommufd_viommu_report_event(struct iommufd_viommu *viommu, + enum iommu_veventq_type type, void *event_data, + size_t data_len); +#else /* !CONFIG_IOMMUFD_DRIVER_CORE */ +static inline int _iommufd_object_depend(struct iommufd_object *obj_dependent, + struct iommufd_object *obj_depended) +{ + return -EOPNOTSUPP; +} + +static inline void +_iommufd_object_undepend(struct iommufd_object *obj_dependent, + struct iommufd_object *obj_depended) +{ +} + +static inline int _iommufd_alloc_mmap(struct iommufd_ctx *ictx, + struct iommufd_object *owner, + phys_addr_t mmio_addr, size_t length, + unsigned long *offset) +{ + return -EOPNOTSUPP; +} + +static inline void _iommufd_destroy_mmap(struct iommufd_ctx *ictx, + struct iommufd_object *owner, + unsigned long offset) +{ +} + +static inline struct device * +iommufd_vdevice_to_device(struct iommufd_vdevice *vdev) +{ + return NULL; +} + +static inline struct device * +iommufd_viommu_find_dev(struct iommufd_viommu *viommu, unsigned long vdev_id) +{ + return NULL; +} + +static inline int iommufd_viommu_get_vdev_id(struct iommufd_viommu *viommu, + struct device *dev, + unsigned long *vdev_id) +{ + return -ENOENT; +} + +static inline int iommufd_viommu_report_event(struct iommufd_viommu *viommu, + enum iommu_veventq_type type, + void *event_data, size_t data_len) +{ + return -EOPNOTSUPP; +} +#endif /* CONFIG_IOMMUFD_DRIVER_CORE */ + +#define VIOMMU_STRUCT_SIZE(drv_struct, member) \ + (sizeof(drv_struct) + \ + BUILD_BUG_ON_ZERO(offsetof(drv_struct, member)) + \ + BUILD_BUG_ON_ZERO(!__same_type(struct iommufd_viommu, \ + ((drv_struct *)NULL)->member))) + +#define VDEVICE_STRUCT_SIZE(drv_struct, member) \ + (sizeof(drv_struct) + \ + BUILD_BUG_ON_ZERO(offsetof(drv_struct, member)) + \ + BUILD_BUG_ON_ZERO(!__same_type(struct iommufd_vdevice, \ + ((drv_struct *)NULL)->member))) + +#define HW_QUEUE_STRUCT_SIZE(drv_struct, member) \ + (sizeof(drv_struct) + \ + BUILD_BUG_ON_ZERO(offsetof(drv_struct, member)) + \ + BUILD_BUG_ON_ZERO(!__same_type(struct iommufd_hw_queue, \ + ((drv_struct *)NULL)->member))) + +/* + * Helpers for IOMMU driver to build/destroy a dependency between two sibling + * structures created by one of the allocators above + */ +#define iommufd_hw_queue_depend(dependent, depended, member) \ + ({ \ + int ret = -EINVAL; \ + \ + static_assert(__same_type(struct iommufd_hw_queue, \ + dependent->member)); \ + static_assert(__same_type(typeof(*dependent), *depended)); \ + if (!WARN_ON_ONCE(dependent->member.viommu != \ + depended->member.viommu)) \ + ret = _iommufd_object_depend(&dependent->member.obj, \ + &depended->member.obj); \ + ret; \ + }) + +#define iommufd_hw_queue_undepend(dependent, depended, member) \ + ({ \ + static_assert(__same_type(struct iommufd_hw_queue, \ + dependent->member)); \ + static_assert(__same_type(typeof(*dependent), *depended)); \ + WARN_ON_ONCE(dependent->member.viommu != \ + depended->member.viommu); \ + _iommufd_object_undepend(&dependent->member.obj, \ + &depended->member.obj); \ + }) + +/* + * Helpers for IOMMU driver to alloc/destroy an mmapable area for a structure. + * + * To support an mmappable MMIO region, kernel driver must first register it to + * iommufd core to allocate an @offset, during a driver-structure initialization + * (e.g. viommu_init op). Then, it should report to user space this @offset and + * the @length of the MMIO region for mmap syscall. + */ +static inline int iommufd_viommu_alloc_mmap(struct iommufd_viommu *viommu, + phys_addr_t mmio_addr, + size_t length, + unsigned long *offset) +{ + return _iommufd_alloc_mmap(viommu->ictx, &viommu->obj, mmio_addr, + length, offset); +} + +static inline void iommufd_viommu_destroy_mmap(struct iommufd_viommu *viommu, + unsigned long offset) +{ + _iommufd_destroy_mmap(viommu->ictx, &viommu->obj, offset); +} +#endif |