From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nick Piggin <npiggin@suse.de>
Subject: Re: [patch 3/5] vfs: introduce FMODE_NEG_OFFSET for allowing
 negative f_pos
Date: Wed, 21 Jul 2010 12:54:37 +1000
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On Tue, Jul 20, 2010 at 03:29:48PM -0700, Andrew Morton wrote:
> From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
> 
> Now, rw_verify_area() checsk f_pos is negative or not.  And if negative,
> returns -EINVAL.
> 
> But, some special files as /dev/(k)mem and /proc/<pid>/mem etc..  has
> negative offsets.  And we can't do any access via read/write to the
> file(device).
> 
> So introduce FMODE_NEG_OFFSET to allow negative file offsets.

Minor nitpick but I don't understand why this is called NEG_OFFSET. It's
a large positive offset into the file so FMODE_UNSIGNED_OFFSET seems
like it would be better.