include/linux/mdev.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Mediated device definition
   4  *
   5  * Copyright (c) 2016, NVIDIA CORPORATION. All rights reserved.
   6  *     Author: Neo Jia <cjia@nvidia.com>
   7  *             Kirti Wankhede <kwankhede@nvidia.com>
   8  */
   9
  10 #ifndef MDEV_H
  11 #define MDEV_H
  12
  13 struct mdev_type;
  14
  15 struct mdev_device {
  16         struct device dev;
  17         guid_t uuid;
  18         void *driver_data;
  19         struct list_head next;
  20         struct mdev_type *type;
  21         struct device *iommu_device;
  22         bool active;
  23 };
  24
  25 static inline struct mdev_device *to_mdev_device(struct device *dev)
  26 {
  27         return container_of(dev, struct mdev_device, dev);
  28 }
  29
  30 /*
  31  * Called by the parent device driver to set the device which represents
  32  * this mdev in iommu protection scope. By default, the iommu device is
  33  * NULL, that indicates using vendor defined isolation.
  34  *
  35  * @dev: the mediated device that iommu will isolate.
  36  * @iommu_device: a pci device which represents the iommu for @dev.
  37  */
  38 static inline void mdev_set_iommu_device(struct mdev_device *mdev,
  39                                          struct device *iommu_device)
  40 {
  41         mdev->iommu_device = iommu_device;
  42 }
  43
  44 static inline struct device *mdev_get_iommu_device(struct mdev_device *mdev)
  45 {
  46         return mdev->iommu_device;
  47 }
  48
  49 unsigned int mdev_get_type_group_id(struct mdev_device *mdev);
  50 unsigned int mtype_get_type_group_id(struct mdev_type *mtype);
  51 struct device *mtype_get_parent_dev(struct mdev_type *mtype);
  52
  53 /**
  54  * struct mdev_parent_ops - Structure to be registered for each parent device to
  55  * register the device to mdev module.
  56  *
  57  * @owner:              The module owner.
  58  * @device_driver:      Which device driver to probe() on newly created devices
  59  * @dev_attr_groups:    Attributes of the parent device.
  60  * @mdev_attr_groups:   Attributes of the mediated device.
  61  * @supported_type_groups: Attributes to define supported types. It is mandatory
  62  *                      to provide supported types.
  63  * @create:             Called to allocate basic resources in parent device's
  64  *                      driver for a particular mediated device. It is
  65  *                      mandatory to provide create ops.
  66  *                      @mdev: mdev_device structure on of mediated device
  67  *                            that is being created
  68  *                      Returns integer: success (0) or error (< 0)
  69  * @remove:             Called to free resources in parent device's driver for
  70  *                      a mediated device. It is mandatory to provide 'remove'
  71  *                      ops.
  72  *                      @mdev: mdev_device device structure which is being
  73  *                             destroyed
  74  *                      Returns integer: success (0) or error (< 0)
  75  * @read:               Read emulation callback
  76  *                      @mdev: mediated device structure
  77  *                      @buf: read buffer
  78  *                      @count: number of bytes to read
  79  *                      @ppos: address.
  80  *                      Retuns number on bytes read on success or error.
  81  * @write:              Write emulation callback
  82  *                      @mdev: mediated device structure
  83  *                      @buf: write buffer
  84  *                      @count: number of bytes to be written
  85  *                      @ppos: address.
  86  *                      Retuns number on bytes written on success or error.
  87  * @ioctl:              IOCTL callback
  88  *                      @mdev: mediated device structure
  89  *                      @cmd: ioctl command
  90  *                      @arg: arguments to ioctl
  91  * @mmap:               mmap callback
  92  *                      @mdev: mediated device structure
  93  *                      @vma: vma structure
  94  * @request:            request callback to release device
  95  *                      @mdev: mediated device structure
  96  *                      @count: request sequence number
  97  * Parent device that support mediated device should be registered with mdev
  98  * module with mdev_parent_ops structure.
  99  **/
 100 struct mdev_parent_ops {
 101         struct module   *owner;
 102         struct mdev_driver *device_driver;
 103         const struct attribute_group **dev_attr_groups;
 104         const struct attribute_group **mdev_attr_groups;
 105         struct attribute_group **supported_type_groups;
 106
 107         int     (*create)(struct mdev_device *mdev);
 108         int     (*remove)(struct mdev_device *mdev);
 109         int     (*open_device)(struct mdev_device *mdev);
 110         void    (*close_device)(struct mdev_device *mdev);
 111         ssize_t (*read)(struct mdev_device *mdev, char __user *buf,
 112                         size_t count, loff_t *ppos);
 113         ssize_t (*write)(struct mdev_device *mdev, const char __user *buf,
 114                          size_t count, loff_t *ppos);
 115         long    (*ioctl)(struct mdev_device *mdev, unsigned int cmd,
 116                          unsigned long arg);
 117         int     (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma);
 118         void    (*request)(struct mdev_device *mdev, unsigned int count);
 119 };
 120
 121 /* interface for exporting mdev supported type attributes */
 122 struct mdev_type_attribute {
 123         struct attribute attr;
 124         ssize_t (*show)(struct mdev_type *mtype,
 125                         struct mdev_type_attribute *attr, char *buf);
 126         ssize_t (*store)(struct mdev_type *mtype,
 127                          struct mdev_type_attribute *attr, const char *buf,
 128                          size_t count);
 129 };
 130
 131 #define MDEV_TYPE_ATTR(_name, _mode, _show, _store)             \
 132 struct mdev_type_attribute mdev_type_attr_##_name =             \
 133         __ATTR(_name, _mode, _show, _store)
 134 #define MDEV_TYPE_ATTR_RW(_name) \
 135         struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RW(_name)
 136 #define MDEV_TYPE_ATTR_RO(_name) \
 137         struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
 138 #define MDEV_TYPE_ATTR_WO(_name) \
 139         struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
 140
 141 /**
 142  * struct mdev_driver - Mediated device driver
 143  * @probe: called when new device created
 144  * @remove: called when device removed
 145  * @driver: device driver structure
 146  *
 147  **/
 148 struct mdev_driver {
 149         int (*probe)(struct mdev_device *dev);
 150         void (*remove)(struct mdev_device *dev);
 151         struct device_driver driver;
 152 };
 153
 154 static inline void *mdev_get_drvdata(struct mdev_device *mdev)
 155 {
 156         return mdev->driver_data;
 157 }
 158 static inline void mdev_set_drvdata(struct mdev_device *mdev, void *data)
 159 {
 160         mdev->driver_data = data;
 161 }
 162 static inline const guid_t *mdev_uuid(struct mdev_device *mdev)
 163 {
 164         return &mdev->uuid;
 165 }
 166
 167 extern struct bus_type mdev_bus_type;
 168
 169 int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops);
 170 void mdev_unregister_device(struct device *dev);
 171
 172 int mdev_register_driver(struct mdev_driver *drv);
 173 void mdev_unregister_driver(struct mdev_driver *drv);
 174
 175 struct device *mdev_parent_dev(struct mdev_device *mdev);
 176 static inline struct device *mdev_dev(struct mdev_device *mdev)
 177 {
 178         return &mdev->dev;
 179 }
 180 static inline struct mdev_device *mdev_from_dev(struct device *dev)
 181 {
 182         return dev->bus == &mdev_bus_type ? to_mdev_device(dev) : NULL;
 183 }
 184
 185 #endif /* MDEV_H */