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Date: Fri, 21 Sep 2001 04:42:22 +0200
From: Andrea Arcangeli <andrea@suse.de>
To: Alexander Viro <viro@math.psu.edu>
Cc: Linus Torvalds <torvalds@transmeta.com>,
        Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: Linux 2.4.10-pre11
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In-Reply-To: <Pine.GSO.4.21.0109202146280.5631-100000@weyl.math.psu.edu>; from viro@math.psu.edu on Thu, Sep 20, 2001 at 09:50:52PM -0400
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On Thu, Sep 20, 2001 at 09:50:52PM -0400, Alexander Viro wrote:
> 	Andrea, what's the point of making blkdev_get() bump ->bd_count
> in case of success and blkdev_put() - drop it?  We _do_ grab a reference
> before calling blkdev_get() - any place where we don't is an immediately
> oopsable hole both in the old an in the new tree.  Notice that you
> do down(&bdev->bd_sem) before that increment of refcount, so if caller
> doesn't hold a reference we are toast.  What's going on there?

I just wanted to make sure the bdev couldn't be released under us by
owning a reference for the whole duration of the blkdev_get/put. But
requiring the caller to hold the reference for us seems saner since the
caller will have to pass the bdev as parameter anyways, so yes it seems
superflous.

Andrea