From patchwork Wed Oct 14 11:20:26 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Suzuki K Poulose X-Patchwork-Id: 7392111 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id F00E2BEEA4 for ; Wed, 14 Oct 2015 11:23:54 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 00F22207A8 for ; Wed, 14 Oct 2015 11:23:54 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 960FE20694 for ; Wed, 14 Oct 2015 11:23:52 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZmK7z-0005aH-3E; Wed, 14 Oct 2015 11:21:51 +0000 Received: from eu-smtp-delivery-143.mimecast.com ([207.82.80.143]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZmK7W-0005O7-Kp for linux-arm-kernel@lists.infradead.org; Wed, 14 Oct 2015 11:21:25 +0000 Received: from cam-owa1.Emea.Arm.com (fw-tnat.cambridge.arm.com [217.140.96.140]) by eu-smtp-1.mimecast.com with ESMTP id uk-mta-18-wI9WooPBSge4JzRFoTE0eg-3; Wed, 14 Oct 2015 12:20:58 +0100 Received: from e106634-lin.cambridge.arm.com ([10.1.2.79]) by cam-owa1.Emea.Arm.com with Microsoft SMTPSVC(6.0.3790.3959); Wed, 14 Oct 2015 12:20:56 +0100 From: "Suzuki K. Poulose" To: linux-arm-kernel@lists.infradead.org Subject: [PATCHv3 03/11] arm64: Introduce helpers for page table levels Date: Wed, 14 Oct 2015 12:20:26 +0100 Message-Id: <1444821634-1689-4-git-send-email-suzuki.poulose@arm.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1444821634-1689-1-git-send-email-suzuki.poulose@arm.com> References: <1444821634-1689-1-git-send-email-suzuki.poulose@arm.com> X-OriginalArrivalTime: 14 Oct 2015 11:20:56.0229 (UTC) FILETIME=[6513CD50:01D10672] X-MC-Unique: wI9WooPBSge4JzRFoTE0eg-3 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20151014_042123_128071_C85F540F X-CRM114-Status: GOOD ( 10.70 ) X-Spam-Score: -4.2 (----) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, steve.capper@linaro.org, ard.biesheuvel@linaro.org, marc.zyngier@arm.com, catalin.marinas@arm.com, "Suzuki K. Poulose" , will.deacon@arm.com, linux-kernel@vger.kernel.org, christoffer.dall@linaro.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Introduce helpers for finding the number of page table levels required for a given VA width, shift for a particular page table level. Convert the existing users to the new helpers. More users to follow. Cc: Ard Biesheuvel Cc: Mark Rutland Cc: Catalin Marinas Cc: Will Deacon Cc: Marc Zyngier Signed-off-by: Suzuki K. Poulose Acked-by: Mark Rutland Acked-by: Mark Rutland Acked-by: Christoffer Dall --- Changes since V2: - Add comments around the macros - Change ARM64_HW_PGTABLE_LEVEL_SHIFT to accept pagetable level as described by ARM ARM --- arch/arm64/include/asm/pgtable-hwdef.h | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index 95c1ec0..c6194ab 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -16,13 +16,31 @@ #ifndef __ASM_PGTABLE_HWDEF_H #define __ASM_PGTABLE_HWDEF_H +/* + * Number of page-table levels required to address 'va_bits' wide + * address, without section mapping. We resolve the top (va_bits - PAGE_SHIFT) + * bits with (PAGE_SHIFT - 3) bits at each page table level. Hence: + * + * levels = DIV_ROUND_UP((va_bits - PAGE_SHIFT), (PAGE_SHIFT - 3)) + * + * We cannot include linux/kernel.h which defines DIV_ROUND_UP here + * due to build issues. So we use the following magic formula. + */ +#define ARM64_HW_PGTABLE_LEVELS(va_bits) (((va_bits) - 4) / (PAGE_SHIFT - 3)) + +/* + * Size mapped by an entry at level n + * We map PAGE_SHIFT - 3 at all levels, except the PAGE_SHIFT bits at the last level + */ +#define ARM64_HW_PGTABLE_LEVEL_SHIFT(n) ((PAGE_SHIFT - 3) * (4 - (n)) + 3) + #define PTRS_PER_PTE (1 << (PAGE_SHIFT - 3)) /* * PMD_SHIFT determines the size a level 2 page table entry can map. */ #if CONFIG_PGTABLE_LEVELS > 2 -#define PMD_SHIFT ((PAGE_SHIFT - 3) * 2 + 3) +#define PMD_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(2) #define PMD_SIZE (_AC(1, UL) << PMD_SHIFT) #define PMD_MASK (~(PMD_SIZE-1)) #define PTRS_PER_PMD PTRS_PER_PTE @@ -32,7 +50,7 @@ * PUD_SHIFT determines the size a level 1 page table entry can map. */ #if CONFIG_PGTABLE_LEVELS > 3 -#define PUD_SHIFT ((PAGE_SHIFT - 3) * 3 + 3) +#define PUD_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(1) #define PUD_SIZE (_AC(1, UL) << PUD_SHIFT) #define PUD_MASK (~(PUD_SIZE-1)) #define PTRS_PER_PUD PTRS_PER_PTE @@ -42,7 +60,8 @@ * PGDIR_SHIFT determines the size a top-level page table entry can map * (depending on the configuration, this level can be 0, 1 or 2). */ -#define PGDIR_SHIFT ((PAGE_SHIFT - 3) * CONFIG_PGTABLE_LEVELS + 3) +#define PGDIR_SHIFT \ + ARM64_HW_PGTABLE_LEVEL_SHIFT(4 - CONFIG_PGTABLE_LEVELS) #define PGDIR_SIZE (_AC(1, UL) << PGDIR_SHIFT) #define PGDIR_MASK (~(PGDIR_SIZE-1)) #define PTRS_PER_PGD (1 << (VA_BITS - PGDIR_SHIFT))