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Date: Fri, 27 Apr 2001 16:31:05 +0200 (MET DST)
From: Bjorn Wesen <bjorn@sparta.lu.se>
To: Padraig Brady <padraig@antefacto.com>
cc: linux-kernel@vger.kernel.org
Subject: Re: ramdisk/tmpfs/ramfs/memfs ?
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On Fri, 27 Apr 2001, Padraig Brady wrote:
> for a partition. If I understand correctly ramfs just points
> to the file data which are pages in the cache marked not to be

It does not even do that - as of 2.4, the VFS in the kernel also knows how
to cache a filestructure itself. It's in the dentry-cache. So ramfs just
provides the thin mapping between VFS operations and the VFS caches
(dentries, inodes, pages) like any other 2.4 filesystem - with the
difference that ramfs does not need to know anything about actually
transferring the cache entries to a backing store (a physical filesystem).

Take a look at fs/ramfs/inode.c, it's just some hundred odd lines of
code and worth reading to find out more about how 2.4's VFS works.

> uncached. Doh! is ramfs supported in 2.2?

Don't think so, for the above reason.

-BW

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