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To: David Woodhouse <dwmw2@infradead.org>
Cc: "Bradley D. LaRonde" <brad@ltc.com>, "Thomas Capricelli" <orzel@kde.org>,
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Subject: Re: Mounting a in-ROM filesystem efficiently
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From: ebiederm@xmission.com (Eric W. Biederman)
Date: 23 Jan 2002 01:01:47 -0700
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David Woodhouse <dwmw2@infradead.org> writes:

> brad@ltc.com said:
> >  That sounds nice, but I cannot imagine how much trouble it would be
> > to implement.
> 
> Adding the pages to the page cache on read_inode() is fairly simple. Hacking 
> the kernel so that readpage() can provide its own page less so.

Well the generic solution is to simply skip readpage and provide (for your fs)
your own versions of generic_file_read and filemap_nopage.  At least
if you want to do it on demand...

Eric