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_device;
  14
  15 /*
  16  * Called by the parent device driver to set the device which represents
  17  * this mdev in iommu protection scope. By default, the iommu device is
  18  * NULL, that indicates using vendor defined isolation.
  19  *
  20  * @dev: the mediated device that iommu will isolate.
  21  * @iommu_device: a pci device which represents the iommu for @dev.
  22  *
  23  * Return 0 for success, otherwise negative error value.
  24  */
  25 int mdev_set_iommu_device(struct device *dev, struct device *iommu_device);
  26
  27 struct device *mdev_get_iommu_device(struct device *dev);
  28
  29 /**
  30  * struct mdev_parent_ops - Structure to be registered for each parent device to
  31  * register the device to mdev module.
  32  *
  33  * @owner:              The module owner.
  34  * @dev_attr_groups:    Attributes of the parent device.
  35  * @mdev_attr_groups:   Attributes of the mediated device.
  36  * @supported_type_groups: Attributes to define supported types. It is mandatory
  37  *                      to provide supported types.
  38  * @create:             Called to allocate basic resources in parent device's
  39  *                      driver for a particular mediated device. It is
  40  *                      mandatory to provide create ops.
  41  *                      @kobj: kobject of type for which 'create' is called.
  42  *                      @mdev: mdev_device structure on of mediated device
  43  *                            that is being created
  44  *                      Returns integer: success (0) or error (< 0)
  45  * @remove:             Called to free resources in parent device's driver for a
  46  *                      a mediated device. It is mandatory to provide 'remove'
  47  *                      ops.
  48  *                      @mdev: mdev_device device structure which is being
  49  *                             destroyed
  50  *                      Returns integer: success (0) or error (< 0)
  51  * @open:               Open mediated device.
  52  *                      @mdev: mediated device.
  53  *                      Returns integer: success (0) or error (< 0)
  54  * @release:            release mediated device
  55  *                      @mdev: mediated device.
  56  * @read:               Read emulation callback
  57  *                      @mdev: mediated device structure
  58  *                      @buf: read buffer
  59  *                      @count: number of bytes to read
  60  *                      @ppos: address.
  61  *                      Retuns number on bytes read on success or error.
  62  * @write:              Write emulation callback
  63  *                      @mdev: mediated device structure
  64  *                      @buf: write buffer
  65  *                      @count: number of bytes to be written
  66  *                      @ppos: address.
  67  *                      Retuns number on bytes written on success or error.
  68  * @ioctl:              IOCTL callback
  69  *                      @mdev: mediated device structure
  70  *                      @cmd: ioctl command
  71  *                      @arg: arguments to ioctl
  72  * @mmap:               mmap callback
  73  *                      @mdev: mediated device structure
  74  *                      @vma: vma structure
  75  * Parent device that support mediated device should be registered with mdev
  76  * module with mdev_parent_ops structure.
  77  **/
  78 struct mdev_parent_ops {
  79         struct module   *owner;
  80         const struct attribute_group **dev_attr_groups;
  81         const struct attribute_group **mdev_attr_groups;
  82         struct attribute_group **supported_type_groups;
  83
  84         int     (*create)(struct kobject *kobj, struct mdev_device *mdev);
  85         int     (*remove)(struct mdev_device *mdev);
  86         int     (*open)(struct mdev_device *mdev);
  87         void    (*release)(struct mdev_device *mdev);
  88         ssize_t (*read)(struct mdev_device *mdev, char __user *buf,
  89                         size_t count, loff_t *ppos);
  90         ssize_t (*write)(struct mdev_device *mdev, const char __user *buf,
  91                          size_t count, loff_t *ppos);
  92         long    (*ioctl)(struct mdev_device *mdev, unsigned int cmd,
  93                          unsigned long arg);
  94         int     (*mmap)(struct mdev_device *mdev, struct vm_area_struct *vma);
  95 };
  96
  97 /* interface for exporting mdev supported type attributes */
  98 struct mdev_type_attribute {
  99         struct attribute attr;
 100         ssize_t (*show)(struct kobject *kobj, struct device *dev, char *buf);
 101         ssize_t (*store)(struct kobject *kobj, struct device *dev,
 102                          const char *buf, size_t count);
 103 };
 104
 105 #define MDEV_TYPE_ATTR(_name, _mode, _show, _store)             \
 106 struct mdev_type_attribute mdev_type_attr_##_name =             \
 107         __ATTR(_name, _mode, _show, _store)
 108 #define MDEV_TYPE_ATTR_RW(_name) \
 109         struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RW(_name)
 110 #define MDEV_TYPE_ATTR_RO(_name) \
 111         struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_RO(_name)
 112 #define MDEV_TYPE_ATTR_WO(_name) \
 113         struct mdev_type_attribute mdev_type_attr_##_name = __ATTR_WO(_name)
 114
 115 /**
 116  * struct mdev_driver - Mediated device driver
 117  * @name: driver name
 118  * @probe: called when new device created
 119  * @remove: called when device removed
 120  * @driver: device driver structure
 121  *
 122  **/
 123 struct mdev_driver {
 124         const char *name;
 125         int  (*probe)(struct device *dev);
 126         void (*remove)(struct device *dev);
 127         struct device_driver driver;
 128 };
 129
 130 #define to_mdev_driver(drv)     container_of(drv, struct mdev_driver, driver)
 131
 132 void *mdev_get_drvdata(struct mdev_device *mdev);
 133 void mdev_set_drvdata(struct mdev_device *mdev, void *data);
 134 const guid_t *mdev_uuid(struct mdev_device *mdev);
 135
 136 extern struct bus_type mdev_bus_type;
 137
 138 int mdev_register_device(struct device *dev, const struct mdev_parent_ops *ops);
 139 void mdev_unregister_device(struct device *dev);
 140
 141 int mdev_register_driver(struct mdev_driver *drv, struct module *owner);
 142 void mdev_unregister_driver(struct mdev_driver *drv);
 143
 144 struct device *mdev_parent_dev(struct mdev_device *mdev);
 145 struct device *mdev_dev(struct mdev_device *mdev);
 146 struct mdev_device *mdev_from_dev(struct device *dev);
 147
 148 #endif /* MDEV_H */