Re: [patch 04/11] vfs: introduce new LSM hooks where vfsmount is available.

[Al Viro <viro@ZenIV.linux.org.uk>]

On Sat, Dec 06, 2008 at 09:24:31PM +0900, Tetsuo Handa wrote:

> > Humm...  What's the story with the last argument (struct file *) in there?
> > Explain that and you've got it merged; other than this part I have no
> > objections to that patch.
> 
> do_sys_ftruncate() calls do_truncate() with "struct file *", whereas
> do_sys_truncate() and may_open() call do_truncate() with NULL.
> TOMOYO is not using the last argument, but I'm passing all arguments without
> modification so that a LSM module can know the last argument if that LSM module
> needs the last argument.

And if such a module ever shows up *and* its authors can give good reasons
for checks in that place that apply to ftruncate(2) but not to truncate(2),
we can always add such argument.  Until then...

Note that similar story with struct nameidata * being passed to fs methods
had caused a lot of mess and we are still not through with it.  Let's
stick to the things that make clear sense...