On Thu, Feb 13, 2014 at 10:56 AM, Miklos Szeredi <miklos@xxxxxxxxxx> wrote:
>
> Fair enough, that allows the thing to be listed, at least.
>
> What about creation? A new syscall?
>
> Removal? unlink(2)?
>
> Should stat(2) succeed with a new filetype?
I think it had better work exactly like a special node (eg character
device etc). I don't know about creation (yes, we might even fake it
with mknod(), or just say that the only way to create them is as part
of the union-fs), but removal and renaming should absolutely *not* be
a new system call. That would be a disaster for any system admin,
having to use special tools to edit the filesystem.
Obviously when it is part of a union mount, whiteouts work differently
- they must *not* show up in getdents, and you can't rename/remove a
whiteout anywhere else. But that is obviously part of the union-fs,
nor the low-level filesystem itself.
Linus
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
