From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A96FFC072B5 for ; Fri, 24 May 2019 18:08:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 864D221773 for ; Fri, 24 May 2019 18:08:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729485AbfEXSIM (ORCPT ); Fri, 24 May 2019 14:08:12 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:48186 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727661AbfEXSIM (ORCPT ); Fri, 24 May 2019 14:08:12 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 49589A78; Fri, 24 May 2019 11:08:11 -0700 (PDT) Received: from fuggles.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E5C8A3F703; Fri, 24 May 2019 11:08:09 -0700 (PDT) Date: Fri, 24 May 2019 19:08:05 +0100 From: Will Deacon To: Robin Murphy Cc: linux-mm@kvack.org, akpm@linux-foundation.org, catalin.marinas@arm.com, anshuman.khandual@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 4/4] arm64: mm: Implement pte_devmap support Message-ID: <20190524180805.GA9697@fuggles.cambridge.arm.com> References: <817d92886fc3b33bcbf6e105ee83a74babb3a5aa.1558547956.git.robin.murphy@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <817d92886fc3b33bcbf6e105ee83a74babb3a5aa.1558547956.git.robin.murphy@arm.com> User-Agent: Mutt/1.11.1+86 (6f28e57d73f2) () Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 23, 2019 at 04:03:16PM +0100, Robin Murphy wrote: > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > index 2c41b04708fe..a6378625d47c 100644 > --- a/arch/arm64/include/asm/pgtable.h > +++ b/arch/arm64/include/asm/pgtable.h > @@ -90,6 +90,7 @@ extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]; > #define pte_write(pte) (!!(pte_val(pte) & PTE_WRITE)) > #define pte_user_exec(pte) (!(pte_val(pte) & PTE_UXN)) > #define pte_cont(pte) (!!(pte_val(pte) & PTE_CONT)) > +#define pte_devmap(pte) (!!(pte_val(pte) & PTE_DEVMAP)) > > #define pte_cont_addr_end(addr, end) \ > ({ unsigned long __boundary = ((addr) + CONT_PTE_SIZE) & CONT_PTE_MASK; \ > @@ -217,6 +218,11 @@ static inline pmd_t pmd_mkcont(pmd_t pmd) > return __pmd(pmd_val(pmd) | PMD_SECT_CONT); > } > > +static inline pte_t pte_mkdevmap(pte_t pte) > +{ > + return set_pte_bit(pte, __pgprot(PTE_DEVMAP)); > +} > + > static inline void set_pte(pte_t *ptep, pte_t pte) > { > WRITE_ONCE(*ptep, pte); > @@ -381,6 +387,9 @@ static inline int pmd_protnone(pmd_t pmd) > > #define pmd_mkhuge(pmd) (__pmd(pmd_val(pmd) & ~PMD_TABLE_BIT)) > > +#define pmd_devmap(pmd) pte_devmap(pmd_pte(pmd)) > +#define pmd_mkdevmap(pmd) pte_pmd(pte_mkdevmap(pmd_pte(pmd))) > + > #define __pmd_to_phys(pmd) __pte_to_phys(pmd_pte(pmd)) > #define __phys_to_pmd_val(phys) __phys_to_pte_val(phys) > #define pmd_pfn(pmd) ((__pmd_to_phys(pmd) & PMD_MASK) >> PAGE_SHIFT) > @@ -537,6 +546,11 @@ static inline phys_addr_t pud_page_paddr(pud_t pud) > return __pud_to_phys(pud); > } > > +static inline int pud_devmap(pud_t pud) > +{ > + return 0; > +} > + > /* Find an entry in the second-level page table. */ > #define pmd_index(addr) (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)) > > @@ -624,6 +638,11 @@ static inline phys_addr_t pgd_page_paddr(pgd_t pgd) > > #define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd_val(pgd)) > > +static inline int pgd_devmap(pgd_t pgd) > +{ > + return 0; > +} I think you need to guard this and pXd_devmap() with CONFIG_TRANSPARENT_HUGEPAGE, otherwise you'll conflict with the dummy definitions in mm.h and the build will fail. Will