-/*
- * SMP-safe: Returns 1 and nd will have valid dentry and mnt, if
- * everything is done. Returns 0 and drops input nd, if lookup failed;
- */
-static int __emul_lookup_dentry(const char *name, struct nameidata *nd)
-{
- if (path_walk(name, nd))
- return 0; /* something went wrong... */
-
- if (!nd->path.dentry->d_inode ||
- S_ISDIR(nd->path.dentry->d_inode->i_mode)) {
- struct path old_path = nd->path;
- struct qstr last = nd->last;
- int last_type = nd->last_type;
- struct fs_struct *fs = current->fs;
-
- /*
- * NAME was not found in alternate root or it's a directory.
- * Try to find it in the normal root:
- */
- nd->last_type = LAST_ROOT;
- read_lock(&fs->lock);
- nd->path = fs->root;
- path_get(&fs->root);
- read_unlock(&fs->lock);
- if (path_walk(name, nd) == 0) {
- if (nd->path.dentry->d_inode) {
- path_put(&old_path);
- return 1;
- }
- path_put(&nd->path);
- }
- nd->path = old_path;
- nd->last = last;
- nd->last_type = last_type;
- }
- return 1;
-}
-
-void set_fs_altroot(void)
-{
- char *emul = __emul_prefix();
- struct nameidata nd;
- struct path path = {}, old_path;
- int err;
- struct fs_struct *fs = current->fs;
-
- if (!emul)
- goto set_it;
- err = path_lookup(emul, LOOKUP_FOLLOW|LOOKUP_DIRECTORY|LOOKUP_NOALT, &nd);
- if (!err)
- path = nd.path;
-set_it:
- write_lock(&fs->lock);
- old_path = fs->altroot;
- fs->altroot = path;
- write_unlock(&fs->lock);
- if (old_path.dentry)
- path_put(&old_path);
-}
-