-static int __ns_get_path(struct path *path, struct ns_common *ns)
-{
- struct vfsmount *mnt = nsfs_mnt;
- struct dentry *dentry;
- struct inode *inode;
- unsigned long d;
-
- rcu_read_lock();
- d = atomic_long_read(&ns->stashed);
- if (!d)
- goto slow;
- dentry = (struct dentry *)d;
- if (!lockref_get_not_dead(&dentry->d_lockref))
- goto slow;
- rcu_read_unlock();
- ns->ops->put(ns);
-got_it:
- path->mnt = mntget(mnt);
- path->dentry = dentry;
- return 0;
-slow:
- rcu_read_unlock();
- inode = new_inode_pseudo(mnt->mnt_sb);
- if (!inode) {
- ns->ops->put(ns);
- return -ENOMEM;
- }
- inode->i_ino = ns->inum;
- simple_inode_init_ts(inode);
- inode->i_flags |= S_IMMUTABLE;
- inode->i_mode = S_IFREG | S_IRUGO;
- inode->i_fop = &ns_file_operations;
- inode->i_private = ns;
-
- dentry = d_make_root(inode); /* not the normal use, but... */
- if (!dentry)
- return -ENOMEM;
- dentry->d_fsdata = (void *)ns->ops;
- d = atomic_long_cmpxchg(&ns->stashed, 0, (unsigned long)dentry);
- if (d) {
- d_delete(dentry); /* make sure ->d_prune() does nothing */
- dput(dentry);
- cpu_relax();
- return -EAGAIN;
- }
- goto got_it;
-}
-