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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E6CAC77B73 for ; Thu, 25 May 2023 03:01:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237673AbjEYDBY (ORCPT ); Wed, 24 May 2023 23:01:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53466 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231126AbjEYDBU (ORCPT ); Wed, 24 May 2023 23:01:20 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 91DD8135; Wed, 24 May 2023 20:01:19 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 6F9C81042; Wed, 24 May 2023 20:02:04 -0700 (PDT) Received: from [10.162.43.6] (unknown [10.162.43.6]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 5E8443F762; Wed, 24 May 2023 20:01:17 -0700 (PDT) Message-ID: <10c85f5c-3332-9130-c6f0-d36b9ea4b549@arm.com> Date: Thu, 25 May 2023 08:31:14 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.10.0 Subject: Re: [PATCH v4 05/36] mm: Add default definition of set_ptes() Content-Language: en-US To: "Matthew Wilcox (Oracle)" , linux-arch@vger.kernel.org Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Mike Rapoport References: <20230315051444.3229621-1-willy@infradead.org> <20230315051444.3229621-6-willy@infradead.org> From: Anshuman Khandual In-Reply-To: <20230315051444.3229621-6-willy@infradead.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/15/23 10:44, Matthew Wilcox (Oracle) wrote: > Most architectures can just define set_pte() and PFN_PTE_SHIFT to > use this definition. It's also a handy spot to document the guarantees > provided by the MM. > > Suggested-by: Mike Rapoport (IBM) > Signed-off-by: Matthew Wilcox (Oracle) > --- > include/linux/pgtable.h | 37 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 37 insertions(+) > > diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h > index c5a51481bbb9..a755fe94b4b4 100644 > --- a/include/linux/pgtable.h > +++ b/include/linux/pgtable.h > @@ -172,6 +172,43 @@ static inline int pmd_young(pmd_t pmd) > } > #endif > > +#ifndef set_ptes > +#ifdef PFN_PTE_SHIFT > +/** > + * set_ptes - Map consecutive pages to a contiguous range of addresses. > + * @mm: Address space to map the pages into. > + * @addr: Address to map the first page at. > + * @ptep: Page table pointer for the first entry. > + * @pte: Page table entry for the first page. > + * @nr: Number of pages to map. > + * > + * May be overridden by the architecture, or the architecture can define > + * set_pte() and PFN_PTE_SHIFT. > + * > + * Context: The caller holds the page table lock. The pages all belong > + * to the same folio. The PTEs are all in the same PMD. > + */ > +static inline void set_ptes(struct mm_struct *mm, unsigned long addr, > + pte_t *ptep, pte_t pte, unsigned int nr) > +{ > + page_table_check_ptes_set(mm, addr, ptep, pte, nr); > + > + for (;;) { > + set_pte(ptep, pte); > + if (--nr == 0) > + break; > + ptep++; > + pte = __pte(pte_val(pte) + (1UL << PFN_PTE_SHIFT)); > + } > +} > +#ifndef set_pte_at > +#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) > +#endif Should not there be a build phase call out when both set_ptes() and PFN_PTE_SHIFT are not defined on a given platform ? --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -204,6 +204,8 @@ static inline void set_ptes(struct mm_struct *mm, unsigned long addr, #ifndef set_pte_at #define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) #endif +#else +#error "You should define PFN_PTE_SHIFT" #endif #else #define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) > +#endif> +#else > +#define set_pte_at(mm, addr, ptep, pte) set_ptes(mm, addr, ptep, pte, 1) > +#endif > + > #ifndef __HAVE_ARCH_PTEP_SET_ACCESS_FLAGS > extern int ptep_set_access_flags(struct vm_area_struct *vma, > unsigned long address, pte_t *ptep,