From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Mon, 23 Jan 2006 10:20:03 +0100 From: Nick Piggin Subject: Re: [rfc] split_page function to split higher order pages? Message-ID: <20060123092002.GA26399@wotan.suse.de> References: <20060121124053.GA911@wotan.suse.de> <1137853024.23974.0.camel@laptopd505.fenrus.org> <20060123054927.GA9960@wotan.suse.de> <20060123084715.GA9241@osiris.boeblingen.de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060123084715.GA9241@osiris.boeblingen.de.ibm.com> Sender: owner-linux-mm@kvack.org Return-Path: To: Heiko Carstens Cc: Nick Piggin , Arjan van de Ven , Linux Kernel Mailing List , Linux Memory Management List List-ID: On Mon, Jan 23, 2006 at 09:47:15AM +0100, Heiko Carstens wrote: > > > > Just wondering what people think of the idea of using a helper > > > > function to split higher order pages instead of doing it manually? > > > > > > Maybe it's worth documenting that this is for kernel (or even > > > architecture) internal use only and that drivers really shouldn't be > > > doing this.. > > > > I guess it doesn't seem like something drivers would need to use > > (and none appear to do anything like it). > > And I thought this could/should be used together with vm_insert_page() that > drivers are supposed to use nowadays instead of remap_pfn_range(). > Why shouldn't drivers use this? > Actually fs/ramfs/file-nommu.c does use this (but it need not because !CONFIG_MMU page allocator already does something similar). But largely, no in-tree drivers use the facility so I think it would be good for the mm folk to consider the first use case if and when it comes up. So I've added a comment in split_page to that effect. Thanks, Nick -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org