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=-4.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH autolearn=unavailable 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 28A02C07542 for ; Mon, 27 May 2019 06:23:11 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EA3C42075E for ; Mon, 27 May 2019 06:23:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ggKpfRon" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EA3C42075E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:From:References:To:Subject:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=PcrYWGpTfK+PP5GFgfcbj+z8hkBRXwO3s+iA2n6JA5w=; b=ggKpfRonAPbvBY XzDMC/ZsKrTg03kVHzErBQ9gtHJ+Wi5ZSjh5VVbm4XOS5rfprzAltDuvMogEpdkD3vMYwYboBBCoZ nADXRP4B8POBGD46P+jZDQAbzoSoPc0VjUhGUdHUawvZZOeNG/v84KzV50671QHizJlJIF5ztDjKb ROXgG18+VwVW28mVBdzegFomm/ChaTePALqeQ0nEPaaFys4/AnbWrLPRiTy2qKzHg2YrMfBldqXlx 5uyvEPXxUZYqJFMFniqCUVO3/M/Uvme8GiYwgQ7h+IWMsgM7rMWVW09gihYTp9XNbIHWqG6Odv9NS N6tajegWx+CaIkTtRtAw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hV92J-0004S1-45; Mon, 27 May 2019 06:23:07 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hV92G-0004Rf-VQ for linux-arm-kernel@lists.infradead.org; Mon, 27 May 2019 06:23:06 +0000 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 CDB861688; Sun, 26 May 2019 23:23:03 -0700 (PDT) Received: from [10.162.40.17] (p8cg001049571a15.blr.arm.com [10.162.40.17]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 794233F59C; Sun, 26 May 2019 23:23:01 -0700 (PDT) Subject: Re: [PATCH v3 4/4] arm64: mm: Implement pte_devmap support To: Will Deacon , Robin Murphy References: <817d92886fc3b33bcbf6e105ee83a74babb3a5aa.1558547956.git.robin.murphy@arm.com> <20190524180805.GA9697@fuggles.cambridge.arm.com> From: Anshuman Khandual Message-ID: Date: Mon, 27 May 2019 11:53:13 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20190524180805.GA9697@fuggles.cambridge.arm.com> Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190526_232305_018320_02B53C82 X-CRM114-Status: GOOD ( 14.86 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-mm@kvack.org, akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 05/24/2019 11:38 PM, Will Deacon wrote: > 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. Just curious why pgd_devmap() also needs to be wrapped in TRANSPARENT_HUGEPAGE config (or use this dummy otherwise). IIUC in case of DAX mappings there can never be a huge mapping at PGD level. It only supports PMD or PUD based ones. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel