Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S937011AbXFGVTh (ORCPT ); Thu, 7 Jun 2007 17:19:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762882AbXFGVT3 (ORCPT ); Thu, 7 Jun 2007 17:19:29 -0400 Received: from nz-out-0506.google.com ([64.233.162.233]:42158 "EHLO nz-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760090AbXFGVT3 (ORCPT ); Thu, 7 Jun 2007 17:19:29 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=tx4QpgDi2UPm1TX922jDKEkf4CjxcRxwGn8DQ26+CplaxlSQEAvt6GqfFyfYtUZU5P96rV0K2PCur6GnLgO+EhqWeGNlYei9BidFn2q+GDBZ6pwe4ky4TlmOnX0LUqCXBTy8lKSDUSdtODO6SZPaEhZ1kw+VFjYcnvv9LsDVOU4= Message-ID: <6934efce0706071419n2557603cl85e820d0612787a@mail.gmail.com> Date: Thu, 7 Jun 2007 14:19:28 -0700 From: "Jared Hulbert" To: carsteno@de.ibm.com Subject: Re: [PATCH 2.6.21] cramfs: add cramfs Linear XIP Cc: "Christoph Hellwig" , "Nick Piggin" , "Andrew Morton" , richard.griffiths@windriver.com, "Richard Griffiths" , Linux-kernel@vger.kernel.org In-Reply-To: <46683B6A.6030306@de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <1179871779.24163.11.camel@localhost.localdomain> <465BB5BA.3050900@yahoo.com.au> <6934efce0706011748p46cf7995vdca0b9cc3f0b06a3@mail.gmail.com> <46612D6F.6000002@yahoo.com.au> <46641472.3080802@de.ibm.com> <6934efce0706060413y6e74512s19d5f468106d4b85@mail.gmail.com> <20070606113351.GA11701@infradead.org> <4666DD88.5030708@de.ibm.com> <20070606162305.GA20600@infradead.org> <46683B6A.6030306@de.ibm.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1251 Lines: 24 > I've had a few beer long discussion with Joern Engel and David > Woodhouse on this one. To cut a long discussion short: the current XIP > infrastructure is not sufficient to be used on top of mtd. We'd need > some extenstions: > - on get_xip_page() we'd need to state if we want the reference > read-only or read+write > - we need a put_xip_page() to return references > - and finally we need a callback for the referece, so that the mtd > driver can ask to get its reference back (in order to unmap from > userland when erasing a block) Yes. And one more thing. We can't assume every page in a file is XIP or not. However, I still can't get even the existing get_xip_page() to work for me so we are getting ahead of ourselves;) Looking back on this thread I realize I haven't confirmed if my cramfs_get_xip_page() gets a page struct. I assume that is my problem? The UML find_iomem() probably returns psuedo iomem with page structs. While ioremap() does not return with page struct backed memory. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/