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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 660FFCA9EA1 for ; Fri, 18 Oct 2019 10:13:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 47FEC21D7C for ; Fri, 18 Oct 2019 10:13:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2633328AbfJRKN1 (ORCPT ); Fri, 18 Oct 2019 06:13:27 -0400 Received: from [217.140.110.172] ([217.140.110.172]:60798 "EHLO foss.arm.com" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S2633317AbfJRKN0 (ORCPT ); Fri, 18 Oct 2019 06:13:26 -0400 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 9BEF1497; Fri, 18 Oct 2019 03:13:03 -0700 (PDT) Received: from e112269-lin.cambridge.arm.com (e112269-lin.cambridge.arm.com [10.1.194.43]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E88BC3F6C4; Fri, 18 Oct 2019 03:13:00 -0700 (PDT) From: Steven Price To: linux-mm@kvack.org Cc: Steven Price , Andy Lutomirski , Ard Biesheuvel , Arnd Bergmann , Borislav Petkov , Catalin Marinas , Dave Hansen , Ingo Molnar , James Morse , =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Peter Zijlstra , Thomas Gleixner , Will Deacon , x86@kernel.org, "H. Peter Anvin" , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Mark Rutland , "Liang, Kan" , Andrew Morton , Mark Rutland Subject: [PATCH v12 01/22] mm: Add generic p?d_leaf() macros Date: Fri, 18 Oct 2019 11:12:27 +0100 Message-Id: <20191018101248.33727-2-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191018101248.33727-1-steven.price@arm.com> References: <20191018101248.33727-1-steven.price@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Exposing the pud/pgd levels of the page tables to walk_page_range() means we may come across the exotic large mappings that come with large areas of contiguous memory (such as the kernel's linear map). For architectures that don't provide all p?d_leaf() macros, provide generic do nothing default that are suitable where there cannot be leaf pages at that level. Futher patches will add implementations for individual architectures. The name p?d_leaf() is chosen to minimize the confusion with existing uses of "large" pages and "huge" pages which do not necessary mean that the entry is a leaf (for example it may be a set of contiguous entries that only take 1 TLB slot). For the purpose of walking the page tables we don't need to know how it will be represented in the TLB, but we do need to know for sure if it is a leaf of the tree. Signed-off-by: Steven Price Acked-by: Mark Rutland --- include/asm-generic/pgtable.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 818691846c90..7f9eced287b7 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -1187,4 +1187,24 @@ static inline bool arch_has_pfn_modify_check(void) #define mm_pmd_folded(mm) __is_defined(__PAGETABLE_PMD_FOLDED) #endif +/* + * p?d_leaf() - true if this entry is a final mapping to a physical address. + * This differs from p?d_huge() by the fact that they are always available (if + * the architecture supports large pages at the appropriate level) even + * if CONFIG_HUGETLB_PAGE is not defined. + * Only meaningful when called on a valid entry. + */ +#ifndef pgd_leaf +#define pgd_leaf(x) 0 +#endif +#ifndef p4d_leaf +#define p4d_leaf(x) 0 +#endif +#ifndef pud_leaf +#define pud_leaf(x) 0 +#endif +#ifndef pmd_leaf +#define pmd_leaf(x) 0 +#endif + #endif /* _ASM_GENERIC_PGTABLE_H */ -- 2.20.1