include/linux/vfio.h

   1 /*
   2  * VFIO API definition
   3  *
   4  * Copyright (C) 2012 Red Hat, Inc.  All rights reserved.
   5  *     Author: Alex Williamson <alex.williamson@redhat.com>
   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  */
  30 struct vfio_device_ops {
  31         char    *name;
  32         int     (*open)(void *device_data);
  33         void    (*release)(void *device_data);
  34         ssize_t (*read)(void *device_data, char __user *buf,
  35                         size_t count, loff_t *ppos);
  36         ssize_t (*write)(void *device_data, const char __user *buf,
  37                          size_t count, loff_t *size);
  38         long    (*ioctl)(void *device_data, unsigned int cmd,
  39                          unsigned long arg);
  40         int     (*mmap)(void *device_data, struct vm_area_struct *vma);
  41 };
  42
  43 extern int vfio_add_group_dev(struct device *dev,
  44                               const struct vfio_device_ops *ops,
  45                               void *device_data);
  46
  47 extern void *vfio_del_group_dev(struct device *dev);
  48 extern struct vfio_device *vfio_device_get_from_dev(struct device *dev);
  49 extern void vfio_device_put(struct vfio_device *device);
  50 extern void *vfio_device_data(struct vfio_device *device);
  51
  52 /**
  53  * struct vfio_iommu_driver_ops - VFIO IOMMU driver callbacks
  54  */
  55 struct vfio_iommu_driver_ops {
  56         char            *name;
  57         struct module   *owner;
  58         void            *(*open)(unsigned long arg);
  59         void            (*release)(void *iommu_data);
  60         ssize_t         (*read)(void *iommu_data, char __user *buf,
  61                                 size_t count, loff_t *ppos);
  62         ssize_t         (*write)(void *iommu_data, const char __user *buf,
  63                                  size_t count, loff_t *size);
  64         long            (*ioctl)(void *iommu_data, unsigned int cmd,
  65                                  unsigned long arg);
  66         int             (*mmap)(void *iommu_data, struct vm_area_struct *vma);
  67         int             (*attach_group)(void *iommu_data,
  68                                         struct iommu_group *group);
  69         void            (*detach_group)(void *iommu_data,
  70                                         struct iommu_group *group);
  71
  72 };
  73
  74 extern int vfio_register_iommu_driver(const struct vfio_iommu_driver_ops *ops);
  75
  76 extern void vfio_unregister_iommu_driver(
  77                                 const struct vfio_iommu_driver_ops *ops);
  78
  79 /**
  80  * offsetofend(TYPE, MEMBER)
  81  *
  82  * @TYPE: The type of the structure
  83  * @MEMBER: The member within the structure to get the end offset of
  84  *
  85  * Simple helper macro for dealing with variable sized structures passed
  86  * from user space.  This allows us to easily determine if the provided
  87  * structure is sized to include various fields.
  88  */
  89 #define offsetofend(TYPE, MEMBER) \
  90         (offsetof(TYPE, MEMBER) + sizeof(((TYPE *)0)->MEMBER))
  91
  92 /*
  93  * External user API
  94  */
  95 extern struct vfio_group *vfio_group_get_external_user(struct file *filep);
  96 extern void vfio_group_put_external_user(struct vfio_group *group);
  97 extern int vfio_external_user_iommu_id(struct vfio_group *group);
  98 extern long vfio_external_check_extension(struct vfio_group *group,
  99                                           unsigned long arg);
 100
 101 #endif /* VFIO_H */