From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from majordomo by infradead.org with local (Exim 3.16 #2) id 148IBU-00007c-00 for mtd-list@infradead.org; Tue, 19 Dec 2000 08:31:44 +0000 From: Shane Nay Reply-To: shane@agendacomputing.com To: David Woodhouse Subject: Re: MTD, generic physmap memory, MTD_BLOCK Date: Mon, 18 Dec 2000 21:31:43 +0000 Content-Type: text/plain; charset="US-ASCII" Cc: Nicolas Pitre , , References: In-Reply-To: MIME-Version: 1.0 Message-Id: <0012182131432A.11759@www.easysolutions.net> Content-Transfer-Encoding: 8bit Sender: owner-mtd@infradead.org List-ID: On Sunday 17 December 2000 22:24, David Woodhouse wrote: > Unless there's something missing (or I'm being dim) that code doesn't do > XIP. It still copies from the cramfs into the page provided to > cramfs_readpage. > > What you want to do is make up some struct pages to represent the pages > of the ROM chip and pre-populate the page cache with those pages directly > - marked readonly, of course. Hehe, no, it's not an XIP implementation. I think I mentioned in my message, even if I didn't make it clear (probably not) that this only made cramfs read directly off of the flash, taking one layer of abstraction out. It kills the buffer, and the copy to buffer that would usually be associated with a dev device, so it speeds up performance of cramfs on a flash device. It's _only_ a performance hack at this point. But we are working on XIP for cramfs. But this requires either expanding the inode, or stealing a bit or two away from GIDS, or UIDs. This is only a "linear addressing" patch. Thanks, Shane. To unsubscribe, send "unsubscribe mtd" to majordomo@infradead.org