Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751976AbaBSAXy (ORCPT ); Tue, 18 Feb 2014 19:23:54 -0500 Received: from mail-ve0-f173.google.com ([209.85.128.173]:40231 "EHLO mail-ve0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751005AbaBSAXw (ORCPT ); Tue, 18 Feb 2014 19:23:52 -0500 MIME-Version: 1.0 In-Reply-To: <20140219000352.GP21483@n2100.arm.linux.org.uk> References: <20140217234644.GA5171@rmk-PC.arm.linux.org.uk> <20140219000352.GP21483@n2100.arm.linux.org.uk> Date: Tue, 18 Feb 2014 16:23:51 -0800 X-Google-Sender-Auth: yTpTt7mTpJuaYbabsp8VenQnkRQ Message-ID: Subject: Re: [GIT PULL] ARM fixes From: Linus Torvalds To: Russell King - ARM Linux , Konrad Rzeszutek Wilk Cc: Linux Kernel Mailing List , linux-mm , James Bottomley , Linux SCSI List , Andrew Morton , ARM SoC , xen-devel@lists.xenproject.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 18, 2014 at 4:03 PM, Russell King - ARM Linux wrote: > > Almost, but not quite. If we're going to avoid u64, then dma_addr_t > woudl be the right type here because we're talking about DMA addresses. Well, phys_addr_t had better be as big as dma_addr_t, because that's what the resource management handles. > We could also switch to keeping this as PFNs - block internally converts > it to a PFN anyway: Yeah, that definitely sounds like it would be a good idea. > Maybe blk_queue_bounce_pfn_limit() so we ensure all users get caught? > >> That said, it's admittedly a disgusting name, and I wonder if we >> should introduce a nicer-named "pfn_to_phys()" that matches the other >> "xyz_to_abc()" functions we have (including "pfn_to_virt()") > > We have these on ARM: > > arch/arm/include/asm/memory.h:#define __pfn_to_phys(pfn) ((phys_addr_t)(pfn) << PAGE_SHIFT) > arch/arm/include/asm/memory.h:#define __phys_to_pfn(paddr) ((unsigned long)((paddr) >> PAGE_SHIFT)) > > it probably makes sense to pick those right out, maybe losing the > __ prefix on them. Yup. >> __va(PFN_PHYS(page_to_pfn(page))); > > Wow. Two things spring to mind there... highmem pages, and don't we > already have page_address() for that? Well, that code clearly cannot handle highmem anyway, but yes, it really smells like xen should use page_address(). Adding Xen people who I didn't add the last time around. Linus -- 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/