xref: /linux-6.15/include/linux/vfio.h (revision 6faeeea4)
1 /*
2  * VFIO API definition
3  *
4  * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
5  *     Author: Alex Williamson <[email protected]>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #ifndef VFIO_H
12 #define VFIO_H
13 
14 
15 #include <linux/iommu.h>
16 #include <linux/mm.h>
17 #include <uapi/linux/vfio.h>
18 
19 /**
20  * struct vfio_device_ops - VFIO bus driver device callbacks
21  *
22  * @open: Called when userspace creates new file descriptor for device
23  * @release: Called when userspace releases file descriptor for device
24  * @read: Perform read(2) on device file descriptor
25  * @write: Perform write(2) on device file descriptor
26  * @ioctl: Perform ioctl(2) on device file descriptor, supporting VFIO_DEVICE_*
27  *         operations documented below
28  * @mmap: Perform mmap(2) on a region of the device file descriptor
29  * @request: Request for the bus driver to release the device
30  */
31 struct vfio_device_ops {
32 	char	*name;
33 	int	(*open)(void *device_data);
34 	void	(*release)(void *device_data);
35 	ssize_t	(*read)(void *device_data, char __user *buf,
36 			size_t count, loff_t *ppos);
37 	ssize_t	(*write)(void *device_data, const char __user *buf,
38 			 size_t count, loff_t *size);
39 	long	(*ioctl)(void *device_data, unsigned int cmd,
40 			 unsigned long arg);
41 	int	(*mmap)(void *device_data, struct vm_area_struct *vma);
42 	void	(*request)(void *device_data, unsigned int count);
43 };
44 
45 extern int vfio_add_group_dev(struct device *dev,
46 			      const struct vfio_device_ops *ops,
47 			      void *device_data);
48 
49 extern void *vfio_del_group_dev(struct device *dev);
50 extern struct vfio_device *vfio_device_get_from_dev(struct device *dev);
51 extern void vfio_device_put(struct vfio_device *device);
52 extern void *vfio_device_data(struct vfio_device *device);
53 
54 /**
55  * struct vfio_iommu_driver_ops - VFIO IOMMU driver callbacks
56  */
57 struct vfio_iommu_driver_ops {
58 	char		*name;
59 	struct module	*owner;
60 	void		*(*open)(unsigned long arg);
61 	void		(*release)(void *iommu_data);
62 	ssize_t		(*read)(void *iommu_data, char __user *buf,
63 				size_t count, loff_t *ppos);
64 	ssize_t		(*write)(void *iommu_data, const char __user *buf,
65 				 size_t count, loff_t *size);
66 	long		(*ioctl)(void *iommu_data, unsigned int cmd,
67 				 unsigned long arg);
68 	int		(*mmap)(void *iommu_data, struct vm_area_struct *vma);
69 	int		(*attach_group)(void *iommu_data,
70 					struct iommu_group *group);
71 	void		(*detach_group)(void *iommu_data,
72 					struct iommu_group *group);
73 
74 };
75 
76 extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
77 
78 extern void vfio_unregister_iommu_driver(
79 				const struct vfio_iommu_driver_ops *ops);
80 
81 /**
82  * offsetofend(TYPE, MEMBER)
83  *
84  * @TYPE: The type of the structure
85  * @MEMBER: The member within the structure to get the end offset of
86  *
87  * Simple helper macro for dealing with variable sized structures passed
88  * from user space.  This allows us to easily determine if the provided
89  * structure is sized to include various fields.
90  */
91 #define offsetofend(TYPE, MEMBER) \
92 	(offsetof(TYPE, MEMBER)	+ sizeof(((TYPE *)0)->MEMBER))
93 
94 /*
95  * External user API
96  */
97 extern struct vfio_group *vfio_group_get_external_user(struct file *filep);
98 extern void vfio_group_put_external_user(struct vfio_group *group);
99 extern int vfio_external_user_iommu_id(struct vfio_group *group);
100 extern long vfio_external_check_extension(struct vfio_group *group,
101 					  unsigned long arg);
102 
103 struct pci_dev;
104 #ifdef CONFIG_EEH
105 extern void vfio_spapr_pci_eeh_open(struct pci_dev *pdev);
106 extern void vfio_spapr_pci_eeh_release(struct pci_dev *pdev);
107 extern long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
108 				       unsigned int cmd,
109 				       unsigned long arg);
110 #else
111 static inline void vfio_spapr_pci_eeh_open(struct pci_dev *pdev)
112 {
113 }
114 
115 static inline void vfio_spapr_pci_eeh_release(struct pci_dev *pdev)
116 {
117 }
118 
119 static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
120 					      unsigned int cmd,
121 					      unsigned long arg)
122 {
123 	return -ENOTTY;
124 }
125 #endif /* CONFIG_EEH */
126 #endif /* VFIO_H */
127