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  * @open:               Open mediated device.
  76  *                      @mdev: mediated device.
  77  *                      Returns integer: success (0) or error (< 0)
  78  * @release:            release mediated device
  79  *                      @mdev: mediated device.
  80  * @read:               Read emulation callback
  81  *                      @mdev: mediated device structure
  82  *                      @buf: read buffer
  83  *                      @count: number of bytes to read
  84  *                      @ppos: address.
  85  *                      Retuns number on bytes read on success or error.
  86  * @write:              Write emulation callback
  87  *                      @mdev: mediated device structure
  88  *                      @buf: write buffer
  89  *                      @count: number of bytes to be written
  90  *                      @ppos: address.
  91  *                      Retuns number on bytes written on success or error.
  92  * @ioctl:              IOCTL callback
  93  *                      @mdev: mediated device structure
  94  *                      @cmd: ioctl command
  95  *                      @arg: arguments to ioctl
  96  * @mmap:               mmap callback
  97  *                      @mdev: mediated device structure
  98  *                      @vma: vma structure
  99  * @request:            request callback to release device
 100  *                      @mdev: mediated device structure
 101  *                      @count: request sequence number
 102  * Parent device that support mediated device should be registered with mdev
 103  * module with mdev_parent_ops structure.
 104  **/
 105 struct mdev_parent_ops {
 106         struct module   *owner;
 107         struct mdev_driver *device_driver;
 108         const struct attribute_group **dev_attr_groups;
 109         const struct attribute_group **mdev_attr_groups;
 110         struct attribute_group **supported_type_groups;
 111
 112         int     (*create)(struct mdev_device *mdev);
 113         int     (*remove)(struct mdev_device *mdev);
 114         int     (*open)(struct mdev_device *mdev);
 115         void    (*release)(struct mdev_device *mdev);
 116         ssize_t (*read)(struct mdev_device *mdev, char __user *buf,
 117                         size_t count, loff_t *ppos);
 118         ssize_t (*write)(struct mdev_device *mdev, const char __user *buf,
 119                          size_t count, loff_t *ppos);
 120         long    (*ioctl)(struct mdev_device *mdev, unsigned int cmd,
 121                          unsigned long arg);
 122         int     (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma);
 123         void    (*request)(struct mdev_device *mdev, unsigned int count);
 124 };
 125
 126 /* interface for exporting mdev supported type attributes */
 127 struct mdev_type_attribute {
 128         struct attribute attr;
 129         ssize_t (*show)(struct mdev_type *mtype,
 130                         struct mdev_type_attribute *attr, char *buf);
 131         ssize_t (*store)(struct mdev_type *mtype,
 132                          struct mdev_type_attribute *attr, const char *buf,
 133                          size_t count);
 134 };
 135
 136 #define MDEV_TYPE_ATTR(_name, _mode, _show, _store)             \
 137 struct mdev_type_attribute mdev_type_attr_##_name =             \
 138         __ATTR(_name, _mode, _show, _store)
 139 #define MDEV_TYPE_ATTR_RW(_name) \
 140         struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RW(_name)
 141 #define MDEV_TYPE_ATTR_RO(_name) \
 142         struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
 143 #define MDEV_TYPE_ATTR_WO(_name) \
 144         struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
 145
 146 /**
 147  * struct mdev_driver - Mediated device driver
 148  * @probe: called when new device created
 149  * @remove: called when device removed
 150  * @driver: device driver structure
 151  *
 152  **/
 153 struct mdev_driver {
 154         int (*probe)(struct mdev_device *dev);
 155         void (*remove)(struct mdev_device *dev);
 156         struct device_driver driver;
 157 };
 158
 159 static inline void *mdev_get_drvdata(struct mdev_device *mdev)
 160 {
 161         return mdev->driver_data;
 162 }
 163 static inline void mdev_set_drvdata(struct mdev_device *mdev, void *data)
 164 {
 165         mdev->driver_data = data;
 166 }
 167 static inline const guid_t *mdev_uuid(struct mdev_device *mdev)
 168 {
 169         return &mdev->uuid;
 170 }
 171
 172 extern struct bus_type mdev_bus_type;
 173
 174 int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops);
 175 void mdev_unregister_device(struct device *dev);
 176
 177 int mdev_register_driver(struct mdev_driver *drv);
 178 void mdev_unregister_driver(struct mdev_driver *drv);
 179
 180 struct device *mdev_parent_dev(struct mdev_device *mdev);
 181 static inline struct device *mdev_dev(struct mdev_device *mdev)
 182 {
 183         return &mdev->dev;
 184 }
 185 static inline struct mdev_device *mdev_from_dev(struct device *dev)
 186 {
 187         return dev->bus == &mdev_bus_type ? to_mdev_device(dev) : NULL;
 188 }
 189
 190 #endif /* MDEV_H */