xref: /linux-6.15/include/linux/iommufd.h (revision 8d7253dc)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2021 Intel Corporation
4  * Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES
5  */
6 #ifndef __LINUX_IOMMUFD_H
7 #define __LINUX_IOMMUFD_H
8 
9 #include <linux/types.h>
10 #include <linux/errno.h>
11 #include <linux/err.h>
12 
13 struct device;
14 struct iommufd_device;
15 struct page;
16 struct iommufd_ctx;
17 struct iommufd_access;
18 struct file;
19 
20 struct iommufd_device *iommufd_device_bind(struct iommufd_ctx *ictx,
21 					   struct device *dev, u32 *id);
22 void iommufd_device_unbind(struct iommufd_device *idev);
23 
24 int iommufd_device_attach(struct iommufd_device *idev, u32 *pt_id);
25 void iommufd_device_detach(struct iommufd_device *idev);
26 
27 struct iommufd_access_ops {
28 	u8 needs_pin_pages : 1;
29 	void (*unmap)(void *data, unsigned long iova, unsigned long length);
30 };
31 
32 enum {
33 	IOMMUFD_ACCESS_RW_READ = 0,
34 	IOMMUFD_ACCESS_RW_WRITE = 1 << 0,
35 	/* Set if the caller is in a kthread then rw will use kthread_use_mm() */
36 	IOMMUFD_ACCESS_RW_KTHREAD = 1 << 1,
37 
38 	/* Only for use by selftest */
39 	__IOMMUFD_ACCESS_RW_SLOW_PATH = 1 << 2,
40 };
41 
42 struct iommufd_access *
43 iommufd_access_create(struct iommufd_ctx *ictx, u32 ioas_id,
44 		      const struct iommufd_access_ops *ops, void *data);
45 void iommufd_access_destroy(struct iommufd_access *access);
46 
47 void iommufd_ctx_get(struct iommufd_ctx *ictx);
48 
49 #if IS_ENABLED(CONFIG_IOMMUFD)
50 struct iommufd_ctx *iommufd_ctx_from_file(struct file *file);
51 void iommufd_ctx_put(struct iommufd_ctx *ictx);
52 
53 int iommufd_access_pin_pages(struct iommufd_access *access, unsigned long iova,
54 			     unsigned long length, struct page **out_pages,
55 			     unsigned int flags);
56 void iommufd_access_unpin_pages(struct iommufd_access *access,
57 				unsigned long iova, unsigned long length);
58 int iommufd_access_rw(struct iommufd_access *access, unsigned long iova,
59 		      void *data, size_t len, unsigned int flags);
60 int iommufd_vfio_compat_ioas_id(struct iommufd_ctx *ictx, u32 *out_ioas_id);
61 #else /* !CONFIG_IOMMUFD */
62 static inline struct iommufd_ctx *iommufd_ctx_from_file(struct file *file)
63 {
64 	return ERR_PTR(-EOPNOTSUPP);
65 }
66 
67 static inline void iommufd_ctx_put(struct iommufd_ctx *ictx)
68 {
69 }
70 
71 static inline int iommufd_access_pin_pages(struct iommufd_access *access,
72 					   unsigned long iova,
73 					   unsigned long length,
74 					   struct page **out_pages,
75 					   unsigned int flags)
76 {
77 	return -EOPNOTSUPP;
78 }
79 
80 static inline void iommufd_access_unpin_pages(struct iommufd_access *access,
81 					      unsigned long iova,
82 					      unsigned long length)
83 {
84 }
85 
86 static inline int iommufd_access_rw(struct iommufd_access *access, unsigned long iova,
87 		      void *data, size_t len, unsigned int flags)
88 {
89 	return -EOPNOTSUPP;
90 }
91 
92 static inline int iommufd_vfio_compat_ioas_id(struct iommufd_ctx *ictx,
93 					      u32 *out_ioas_id)
94 {
95 	return -EOPNOTSUPP;
96 }
97 #endif /* CONFIG_IOMMUFD */
98 #endif
99