LXR linux/include/kvm/iodev.h

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2
   3#ifndef __KVM_IODEV_H__
   4#define __KVM_IODEV_H__
   5
   6#include <linux/kvm_types.h>
   7#include <linux/errno.h>
   8
   9struct kvm_io_device;
  10struct kvm_vcpu;
  11
  12/**
  13 * kvm_io_device_ops are called under kvm slots_lock.
  14 * read and write handlers return 0 if the transaction has been handled,
  15 * or non-zero to have it passed to the next device.
  16 **/
  17struct kvm_io_device_ops {
  18        int (*read)(struct kvm_vcpu *vcpu,
  19                    struct kvm_io_device *this,
  20                    gpa_t addr,
  21                    int len,
  22                    void *val);
  23        int (*write)(struct kvm_vcpu *vcpu,
  24                     struct kvm_io_device *this,
  25                     gpa_t addr,
  26                     int len,
  27                     const void *val);
  28        void (*destructor)(struct kvm_io_device *this);
  29};
  30
  31
  32struct kvm_io_device {
  33        const struct kvm_io_device_ops *ops;
  34};
  35
  36static inline void kvm_iodevice_init(struct kvm_io_device *dev,
  37                                     const struct kvm_io_device_ops *ops)
  38{
  39        dev->ops = ops;
  40}
  41
  42static inline int kvm_iodevice_read(struct kvm_vcpu *vcpu,
  43                                    struct kvm_io_device *dev, gpa_t addr,
  44                                    int l, void *v)
  45{
  46        return dev->ops->read ? dev->ops->read(vcpu, dev, addr, l, v)
  47                                : -EOPNOTSUPP;
  48}
  49
  50static inline int kvm_iodevice_write(struct kvm_vcpu *vcpu,
  51                                     struct kvm_io_device *dev, gpa_t addr,
  52                                     int l, const void *v)
  53{
  54        return dev->ops->write ? dev->ops->write(vcpu, dev, addr, l, v)
  55                                 : -EOPNOTSUPP;
  56}
  57
  58static inline void kvm_iodevice_destructor(struct kvm_io_device *dev)
  59{
  60        if (dev->ops->destructor)
  61                dev->ops->destructor(dev);
  62}
  63
  64#endif /* __KVM_IODEV_H__ */
  65