Re: what is necessary for directory hard links

From: Joshua Hudson
Date: Sat Jul 22 2006 - 14:13:15 EST


On 7/22/06, Bodo Eggert <7eggert@xxxxxxxxxxxx> wrote:
Horst H. von Brand <vonbrand@xxxxxxxxxxxx> wrote:

> Joshua Hudson <joshudson@xxxxxxxxx> wrote:
>> This patch is the sum total of all that I had to change in the kernel
>> VFS layer to support hard links to directories
>
> Can't be done, as it creates the possibility of loops.

Don't do that then?
Exactly.

> Detecting unconnected subgraphs uses a /lot/ of memory; and much worse, you
> have to stop (almost) all filesystem activity while doing it.
I know.

I just decided the price is worth it.

In my filesystem, any attempt to create a loop of hard links
is detected and cancelled. Unlinking a directory requires it
to be empty if the last link is being removed. "." and ".."
links are counted separately from real links, so that is easy.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/