From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754735Ab0KVNNM (ORCPT ); Mon, 22 Nov 2010 08:13:12 -0500 Received: from service87.mimecast.com ([94.185.240.25]:54506 "HELO service87.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752433Ab0KVNNM convert rfc822-to-8bit (ORCPT ); Mon, 22 Nov 2010 08:13:12 -0500 X-Greylist: delayed 777 seconds by postgrey-1.27 at vger.kernel.org; Mon, 22 Nov 2010 08:13:11 EST Subject: Re: [PATCH v2 01/20] ARM: LPAE: Use PMD_(SHIFT|SIZE|MASK) instead of PGDIR_* From: Catalin Marinas To: Russell King - ARM Linux Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org In-Reply-To: <20101122124353.GB31227@n2100.arm.linux.org.uk> References: <1289584840-18097-1-git-send-email-catalin.marinas@arm.com> <1289584840-18097-2-git-send-email-catalin.marinas@arm.com> <20101122124353.GB31227@n2100.arm.linux.org.uk> Organization: ARM Limited Date: Mon, 22 Nov 2010 13:00:10 +0000 Message-ID: <1290430810.29754.9.camel@e102109-lin.cambridge.arm.com> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 X-OriginalArrivalTime: 22 Nov 2010 13:00:10.0742 (UTC) FILETIME=[320F2160:01CB8A45] X-MC-Unique: 110112213001200301 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2010-11-22 at 12:43 +0000, Russell King - ARM Linux wrote: > On Fri, Nov 12, 2010 at 06:00:21PM +0000, Catalin Marinas wrote: > > diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c > > index 8c19595..40b386c 100644 > > --- a/arch/arm/kernel/smp.c > > +++ b/arch/arm/kernel/smp.c > > @@ -78,7 +78,7 @@ static inline void identity_mapping_add(pgd_t *pgd, unsigned long start, > > if (cpu_architecture() <= CPU_ARCH_ARMv5TEJ && !cpu_is_xscale()) > > prot |= PMD_BIT4; > > > > - for (addr = start & PGDIR_MASK; addr < end;) { > > + for (addr = start & PMD_MASK; addr < end;) { > > pmd = pmd_offset(pgd + pgd_index(addr), addr); > > pmd[0] = __pmd(addr | prot); > > addr += SECTION_SIZE; > > @@ -95,7 +95,7 @@ static inline void identity_mapping_del(pgd_t *pgd, unsigned long start, > > unsigned long addr; > > pmd_t *pmd; > > > > - for (addr = start & PGDIR_MASK; addr < end; addr += PGDIR_SIZE) { > > + for (addr = start & PMD_MASK; addr < end; addr += PMD_SIZE) { > > pmd = pmd_offset(pgd + pgd_index(addr), addr); > > pmd[0] = __pmd(0); > > pmd[1] = __pmd(0); > ... > > @@ -1068,12 +1068,12 @@ void setup_mm_for_reboot(char mode) > > base_pmdval |= PMD_BIT4; > > > > for (i = 0; i < FIRST_USER_PGD_NR + USER_PTRS_PER_PGD; i++, pgd++) { > > - unsigned long pmdval = (i << PGDIR_SHIFT) | base_pmdval; > > + unsigned long pmdval = (i << PMD_SHIFT) | base_pmdval; > > pmd_t *pmd; > > > > - pmd = pmd_off(pgd, i << PGDIR_SHIFT); > > + pmd = pmd_off(pgd, i << PMD_SHIFT); > > pmd[0] = __pmd(pmdval); > > - pmd[1] = __pmd(pmdval + (1 << (PGDIR_SHIFT - 1))); > > + pmd[1] = __pmd(pmdval + (1 << (PMD_SHIFT - 1))); > > flush_pmd_entry(pmd); > > } > > > > This lot really does need unifying - and in any case this last addition > should be using 'SECTION SIZE' not something related to PMD shifts. On the classic page tables, the PMD_SHIFT is 21 while the SECTION_SHIFT is 20. They have slightly different meaning. But we currently have some hacks to cope with PMD_SHIFT being 21 by writing the pmd[0] and pmd[1] in the same call. The way I see to use SECTION_SHIFT is to drop the pmd[] array (but haven't looked closely enough). With LPAE I have a few #ifndef around pmd[1] setting. > Strangely, it's something I've done over the weekend... OK, the more clean-up the better. -- Catalin