1 files changed, 304 insertions, 9 deletions

diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h
index 1129a36a74c4..6e7efe83bc5d 100644
--- a/include/linux/iommufd.h
+++ b/include/linux/iommufd.h
@@ -6,23 +6,70 @@
 #ifndef __LINUX_IOMMUFD_H
 #define __LINUX_IOMMUFD_H
 
-#include <linux/types.h>
-#include <linux/errno.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;
-struct iommufd_ctx;
-struct iommufd_access;
-struct file;
+
+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, u32 *pt_id);
-void iommufd_device_detach(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;
@@ -44,12 +91,117 @@ 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,
@@ -86,8 +238,9 @@ static inline void iommufd_access_unpin_pages(struct iommufd_access *access,
 {
 }
 
-static inline int iommufd_access_rw(struct iommufd_access *access, unsigned long iova,
-		      void *data, size_t len, unsigned int flags)
+static inline int iommufd_access_rw(struct iommufd_access *access,
+				    unsigned long iova, void *data, size_t len,
+				    unsigned int flags)
 {
 	return -EOPNOTSUPP;
 }
@@ -102,4 +255,146 @@ 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