LXR qemu/hw/virtio/vhost-backend.c

   1/*
   2 * vhost-backend
   3 *
   4 * Copyright (c) 2013 Virtual Open Systems Sarl.
   5 *
   6 * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7 * See the COPYING file in the top-level directory.
   8 *
   9 */
  10
  11#include "hw/virtio/vhost.h"
  12#include "hw/virtio/vhost-backend.h"
  13#include "qemu/error-report.h"
  14
  15#include <sys/ioctl.h>
  16
  17static int vhost_kernel_call(struct vhost_dev *dev, unsigned long int request,
  18                             void *arg)
  19{
  20    int fd = (uintptr_t) dev->opaque;
  21
  22    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
  23
  24    return ioctl(fd, request, arg);
  25}
  26
  27static int vhost_kernel_init(struct vhost_dev *dev, void *opaque)
  28{
  29    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
  30
  31    dev->opaque = opaque;
  32
  33    return 0;
  34}
  35
  36static int vhost_kernel_cleanup(struct vhost_dev *dev)
  37{
  38    int fd = (uintptr_t) dev->opaque;
  39
  40    assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_KERNEL);
  41
  42    return close(fd);
  43}
  44
  45static const VhostOps kernel_ops = {
  46        .backend_type = VHOST_BACKEND_TYPE_KERNEL,
  47        .vhost_call = vhost_kernel_call,
  48        .vhost_backend_init = vhost_kernel_init,
  49        .vhost_backend_cleanup = vhost_kernel_cleanup
  50};
  51
  52int vhost_set_backend_type(struct vhost_dev *dev, VhostBackendType backend_type)
  53{
  54    int r = 0;
  55
  56    switch (backend_type) {
  57    case VHOST_BACKEND_TYPE_KERNEL:
  58        dev->vhost_ops = &kernel_ops;
  59        break;
  60    case VHOST_BACKEND_TYPE_USER:
  61        dev->vhost_ops = &user_ops;
  62        break;
  63    default:
  64        error_report("Unknown vhost backend type");
  65        r = -1;
  66    }
  67
  68    return r;
  69}
  70