From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [RFC][patch 0/2] mm: remove PageReserved From: Benjamin Herrenschmidt In-Reply-To: <20050809204100.B29945@flint.arm.linux.org.uk> References: <42F57FCA.9040805@yahoo.com.au> <200508090710.00637.phillips@arcor.de> <1123562392.4370.112.camel@localhost> <42F83849.9090107@yahoo.com.au> <20050809080853.A25492@flint.arm.linux.org.uk> <523240000.1123598289@[10.10.2.4]> <20050809204100.B29945@flint.arm.linux.org.uk> Content-Type: text/plain Date: Wed, 10 Aug 2005 11:27:24 +0200 Message-Id: <1123666046.30257.226.camel@gaston> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Russell King Cc: "Martin J. Bligh" , Nick Piggin , ncunningham@cyclades.com, Daniel Phillips , Linux Kernel Mailing List , Linux Memory Management , Hugh Dickins , Linus Torvalds , Andrew Morton , Andrea Arcangeli List-ID: On Tue, 2005-08-09 at 20:41 +0100, Russell King wrote: > On Tue, Aug 09, 2005 at 07:38:52AM -0700, Martin J. Bligh wrote: > > pfn_valid() doesn't tell you it's RAM or not - it tells you whether you > > have a backing struct page for that address. Could be an IO mapped device, > > a small memory hole, whatever. > > The only things which have a struct page is RAM. Nothing else does. Well, not anymore :) With sparsemem, you can cheat now and have struct page for non-RAM, and this is actually useful. I want some IO space to be "context switchable" and thus map it with nopage() functionality, etc... Ben. -- 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