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Date: Sat, 3 Apr 2004 02:04:25 +0100
From: Jamie Lokier <jamie@shareable.org>
To: Pavel Machek <pavel@ucw.cz>
Cc: =?iso-8859-1?Q?J=F6rn?= Engel <joern@wohnheim.fh-wedel.de>, mj@ucw.cz,
       jack@ucw.cz, "Patrick J. LoPresti" <patl@users.sourceforge.net>,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] cowlinks v2
Message-ID: <20040403010425.GJ653@mail.shareable.org>
References: <20040320152328.GA8089@wohnheim.fh-wedel.de> <20040329171245.GB1478@elf.ucw.cz> <s5g7jx31int.fsf@patl=users.sf.net> <20040329231635.GA374@elf.ucw.cz> <20040402165440.GB24861@wohnheim.fh-wedel.de> <20040402180128.GA363@elf.ucw.cz> <20040402181707.GA28112@wohnheim.fh-wedel.de> <20040402182357.GB410@elf.ucw.cz> <20040402200921.GC653@mail.shareable.org> <20040402213933.GB246@elf.ucw.cz>
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Here's a tricky situation:

   1. A file is cowlinked.  Then each cowlink is mmap()'d, one per process.

   2. At this point both mappings share the same pages in RAM.

   3. Then one of the cowlinks is written to...

-- Jamie