Re: v7.0-rc1, name_to_handle_at(..., AT_EMPTY_PATH)

[hooanon05g@gmail.com]

Al Viro:
> The last point where LOOKUP_EMPTY (or AT_EMPTY_PATH) matters is (and had
> always been) getname_flags(); pathname resolution proper doesn't care.

Filesystems recieved LOOKUP_EMPTY before v7.0-rc1 and could use it to
detect a case like this.

	fd = open("fileA");
	unlink("fileA");
	name_to_handle_at(fd, "", fh, &mnt_id, AT_EMPTY_PATH);

The flag was used to support
- unlinked but still alive inode
- without its name
and d_revalidate() should handle it still valid.

Yes, the filesystem is out-of-tree.
Now I understand that LOOKUP_EMPTY is not passed to filesystem
intentionally.


Thank you
J. R. Okajima