static int __init anon_inode_init(void)
{
anon_inode_mnt = kern_mount(&anon_inode_fs_type);
if (IS_ERR(anon_inode_mnt))
panic("anon_inode_init() kernel mount failed (%ld)\n", PTR_ERR(anon_inode_mnt));
anon_inode_inode = alloc_anon_inode(anon_inode_mnt->mnt_sb);
if (IS_ERR(anon_inode_inode))
panic("anon_inode_init() inode allocation failed (%ld)\n", PTR_ERR(anon_inode_inode));
return 0;
}
static struct inode *drm_fs_inode_new(void)
{
struct inode *inode;
int r;
r = simple_pin_fs(&drm_fs_type, &drm_fs_mnt, &drm_fs_cnt);
if (r < 0) {
DRM_ERROR("Cannot mount pseudo fs: %d\n", r);
return ERR_PTR(r);
}
inode = alloc_anon_inode(drm_fs_mnt->mnt_sb);
if (IS_ERR(inode))
simple_release_fs(&drm_fs_mnt, &drm_fs_cnt);
return inode;
}
static struct file *cxl_getfile(const char *name,
const struct file_operations *fops,
void *priv, int flags)
{
struct file *file;
struct inode *inode;
int rc;
/* strongly inspired by anon_inode_getfile() */
if (fops->owner && !try_module_get(fops->owner))
return ERR_PTR(-ENOENT);
rc = simple_pin_fs(&cxl_fs_type, &cxl_vfs_mount, &cxl_fs_cnt);
if (rc < 0) {
pr_err("Cannot mount cxl pseudo filesystem: %d\n", rc);
file = ERR_PTR(rc);
goto err_module;
}
inode = alloc_anon_inode(cxl_vfs_mount->mnt_sb);
if (IS_ERR(inode)) {
file = ERR_CAST(inode);
goto err_fs;
}
file = alloc_file_pseudo(inode, cxl_vfs_mount, name,
flags & (O_ACCMODE | O_NONBLOCK), fops);
if (IS_ERR(file))
goto err_inode;
file->private_data = priv;
return file;
err_inode:
iput(inode);
err_fs:
simple_release_fs(&cxl_vfs_mount, &cxl_fs_cnt);
err_module:
module_put(fops->owner);
return file;
}
static int virtballoon_probe(struct virtio_device *vdev)
{
struct virtio_balloon *vb;
__u32 poison_val;
int err;
if (!vdev->config->get) {
dev_err(&vdev->dev, "%s failure: config access disabled\n",
__func__);
return -EINVAL;
}
vdev->priv = vb = kzalloc(sizeof(*vb), GFP_KERNEL);
if (!vb) {
err = -ENOMEM;
goto out;
}
INIT_WORK(&vb->update_balloon_stats_work, update_balloon_stats_func);
INIT_WORK(&vb->update_balloon_size_work, update_balloon_size_func);
spin_lock_init(&vb->stop_update_lock);
mutex_init(&vb->balloon_lock);
init_waitqueue_head(&vb->acked);
vb->vdev = vdev;
balloon_devinfo_init(&vb->vb_dev_info);
err = init_vqs(vb);
if (err)
goto out_free_vb;
#ifdef CONFIG_BALLOON_COMPACTION
balloon_mnt = kern_mount(&balloon_fs);
if (IS_ERR(balloon_mnt)) {
err = PTR_ERR(balloon_mnt);
goto out_del_vqs;
}
vb->vb_dev_info.migratepage = virtballoon_migratepage;
vb->vb_dev_info.inode = alloc_anon_inode(balloon_mnt->mnt_sb);
if (IS_ERR(vb->vb_dev_info.inode)) {
err = PTR_ERR(vb->vb_dev_info.inode);
kern_unmount(balloon_mnt);
goto out_del_vqs;
}
vb->vb_dev_info.inode->i_mapping->a_ops = &balloon_aops;
#endif
if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT)) {
/*
* There is always one entry reserved for cmd id, so the ring
* size needs to be at least two to report free page hints.
*/
if (virtqueue_get_vring_size(vb->free_page_vq) < 2) {
err = -ENOSPC;
goto out_del_vqs;
}
vb->balloon_wq = alloc_workqueue("balloon-wq",
WQ_FREEZABLE | WQ_CPU_INTENSIVE, 0);
if (!vb->balloon_wq) {
err = -ENOMEM;
goto out_del_vqs;
}
INIT_WORK(&vb->report_free_page_work, report_free_page_func);
vb->cmd_id_received = VIRTIO_BALLOON_CMD_ID_STOP;
vb->cmd_id_active = cpu_to_virtio32(vb->vdev,
VIRTIO_BALLOON_CMD_ID_STOP);
vb->cmd_id_stop = cpu_to_virtio32(vb->vdev,
VIRTIO_BALLOON_CMD_ID_STOP);
vb->num_free_page_blocks = 0;
spin_lock_init(&vb->free_page_list_lock);
INIT_LIST_HEAD(&vb->free_page_list);
if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON)) {
memset(&poison_val, PAGE_POISON, sizeof(poison_val));
virtio_cwrite(vb->vdev, struct virtio_balloon_config,
poison_val, &poison_val);
}
}
/*
* We continue to use VIRTIO_BALLOON_F_DEFLATE_ON_OOM to decide if a
* shrinker needs to be registered to relieve memory pressure.
*/
if (virtio_has_feature(vb->vdev, VIRTIO_BALLOON_F_DEFLATE_ON_OOM)) {
err = virtio_balloon_register_shrinker(vb);
if (err)
goto out_del_balloon_wq;
}
virtio_device_ready(vdev);
if (towards_target(vb))
virtballoon_changed(vdev);
return 0;
out_del_balloon_wq:
if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT))
destroy_workqueue(vb->balloon_wq);
out_del_vqs:
vdev->config->del_vqs(vdev);
out_free_vb:
kfree(vb);
out:
return err;
}
static int virtballoon_probe(struct virtio_device *vdev)
{
struct virtio_balloon *vb;
int err;
if (!vdev->config->get) {
dev_err(&vdev->dev, "%s failure: config access disabled\n",
__func__);
return -EINVAL;
}
vdev->priv = vb = kmalloc(sizeof(*vb), GFP_KERNEL);
if (!vb) {
err = -ENOMEM;
goto out;
}
INIT_WORK(&vb->update_balloon_stats_work, update_balloon_stats_func);
INIT_WORK(&vb->update_balloon_size_work, update_balloon_size_func);
spin_lock_init(&vb->stop_update_lock);
vb->stop_update = false;
vb->num_pages = 0;
mutex_init(&vb->balloon_lock);
init_waitqueue_head(&vb->acked);
vb->vdev = vdev;
balloon_devinfo_init(&vb->vb_dev_info);
err = init_vqs(vb);
if (err)
goto out_free_vb;
vb->nb.notifier_call = virtballoon_oom_notify;
vb->nb.priority = VIRTBALLOON_OOM_NOTIFY_PRIORITY;
err = register_oom_notifier(&vb->nb);
if (err < 0)
goto out_del_vqs;
#ifdef CONFIG_BALLOON_COMPACTION
balloon_mnt = kern_mount(&balloon_fs);
if (IS_ERR(balloon_mnt)) {
err = PTR_ERR(balloon_mnt);
unregister_oom_notifier(&vb->nb);
goto out_del_vqs;
}
vb->vb_dev_info.migratepage = virtballoon_migratepage;
vb->vb_dev_info.inode = alloc_anon_inode(balloon_mnt->mnt_sb);
if (IS_ERR(vb->vb_dev_info.inode)) {
err = PTR_ERR(vb->vb_dev_info.inode);
kern_unmount(balloon_mnt);
unregister_oom_notifier(&vb->nb);
vb->vb_dev_info.inode = NULL;
goto out_del_vqs;
}
vb->vb_dev_info.inode->i_mapping->a_ops = &balloon_aops;
#endif
virtio_device_ready(vdev);
if (towards_target(vb))
virtballoon_changed(vdev);
return 0;
out_del_vqs:
vdev->config->del_vqs(vdev);
out_free_vb:
kfree(vb);
out:
return err;
}
