Re: [RFC, PATCH] dont insert sockets/pipes dentries intodentry_hashtable.

[Eric Dumazet]

David Miller a écrit :
> From: Eric Dumazet <dada1@xxxxxxxxxxxxx>
> Date: Tue, 31 Oct 2006 19:48:48 +0100
>
> > We currently insert sockets/pipes dentries into the global dentry
> > hashtable.  This is *useless* because there is currently no way
> > these entries can be used for a lookup(). (/proc/xxx/fd/xxx uses a
> > different mechanism)
>
> It turns out that while procfs uses a different "mechanism", those
> procfs symlinks do point to the real socket dentry, so when you
> readlink() on it you do d_path() on the real socket dentry.
>
> If you unhash these things, I'm pretty sure you'll see an ugly
> "(deleted)" at the end of the symlink string for /proc/$pid/fd/$X
> files that are sockets or something like that.

No no, my patch takes care of that.

You still see the right link for pipes and sockets on /proc/$pid/fd/XXX

And " (deleted)" is correctly added to deleted files.


> Al Viro just suggested a way around this to me:
>
> 1) Just mark the dentry HASHED by hand in the dentry flags, but don't
>    actually hash it.
>
> 2) Create a special dentry->d_deleted method for sockets that returns
>    0 and clears by hand the HASHED flag bit in the dentry (see what
>    dput() does when this happens).
>
> It's an abuse but it will work.
Why hack when a proper thing can be done ?

-
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/