Re: [PATCH 6/6] fs: Introduce kern_mount_special() to mount specialvfs

[Eric Dumazet]

Christoph Hellwig a écrit :
> On Thu, Nov 27, 2008 at 12:32:59AM +0100, Eric Dumazet wrote:
> > This function arms a flag (MNT_SPECIAL) on the vfs, to avoid
> > refcounting on permanent system vfs.
> > Use this function for sockets, pipes, anonymous fds.
>
> special is not a useful name for a flag, by definition everything that
> needs a flag is special compared to the version that doesn't need a
> flag.
>
> The general idea of skippign the writer counts makes sense, but please
> give it a descriptive name that explains the not unmountable thing.
> And please kill your kern_mount wrapper and just set the flag manually.
>
> Also I think it should be a superblock flag, not a mount flag as you
> don't want thse to differ for multiple mounts of the same filesystem.

Hum.. we have a superblock flag already, but testing it in mntput()/mntget()
is going to be a litle bit expensive if we add a derefence ?

if (mnt && mnt->mnt_sb->s_flags & MS_SPECIAL) {
  ...
}

--
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/