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Subject: Re: [PATCH 0/4] IMA: making i_readcount a first class inode citizen
From: Mimi Zohar <zohar@linux.vnet.ibm.com>
To: Eric Paris <eparis@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Dave Chinner <david@fromorbit.com>, linux-kernel@vger.kernel.org,
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        Matthew Wilcox <matthew@wil.cx>
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Date: Thu, 28 Oct 2010 20:30:26 -0400
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On Thu, 2010-10-28 at 18:45 -0400, Eric Paris wrote:
> On Thu, 2010-10-28 at 15:29 -0700, Linus Torvalds wrote:
> > On Thu, Oct 28, 2010 at 3:24 PM, Dave Chinner <david@fromorbit.com> wrote:
> > >
> > > Why the wrapper functions and locking? Why not an atomic variable like
> > > i_writecount?
> > 
> > Indeed. With moving this more into the VFS, let's just make sure it
> > looks like i_writecount as much as possible.
> 
> My thought was that the IMA read/write checks should happen AFTER the
> i_writecount and i_readcount counters were updated.  Thus even if we
> raced with another task we can rest assured that the other task would
> catch the situation we missed....
> 
> -Eric

Thanks Eric. My misunderstanding. Will update the patches, making
i_readcount atomic.

Mimi