From patchwork Mon Jul 11 07:05:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 12912842 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 722B8CCA485 for ; Mon, 11 Jul 2022 07:06:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229909AbiGKHGt (ORCPT ); Mon, 11 Jul 2022 03:06:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229841AbiGKHGi (ORCPT ); Mon, 11 Jul 2022 03:06:38 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 645A81A39B; Mon, 11 Jul 2022 00:06:36 -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 82AB2150C; Mon, 11 Jul 2022 00:06:36 -0700 (PDT) Received: from a077893.arm.com (unknown [10.163.45.183]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B4EB43F70D; Mon, 11 Jul 2022 00:06:28 -0700 (PDT) From: Anshuman Khandual To: linux-mm@kvack.org, akpm@linux-foundation.org Cc: hch@infradead.org, christophe.leroy@csgroup.eu, Anshuman Khandual , linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, x86@kernel.org, openrisc@lists.librecores.org, linux-xtensa@linux-xtensa.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-parisc@vger.kernel.org, linux-alpha@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-um@lists.infradead.org, linux-sh@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH V7 02/26] mm/mmap: Define DECLARE_VM_GET_PAGE_PROT Date: Mon, 11 Jul 2022 12:35:36 +0530 Message-Id: <20220711070600.2378316-3-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220711070600.2378316-1-anshuman.khandual@arm.com> References: <20220711070600.2378316-1-anshuman.khandual@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org This just converts the generic vm_get_page_prot() implementation into a new macro i.e DECLARE_VM_GET_PAGE_PROT which later can be used across platforms when enabling them with ARCH_HAS_VM_GET_PAGE_PROT. This does not create any functional change. Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Christophe Leroy Suggested-by: Christoph Hellwig Signed-off-by: Anshuman Khandual --- include/linux/pgtable.h | 28 ++++++++++++++++++++++++++++ mm/mmap.c | 26 +------------------------- 2 files changed, 29 insertions(+), 25 deletions(-) diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h index 3cdc16cfd867..014ee8f0fbaa 100644 --- a/include/linux/pgtable.h +++ b/include/linux/pgtable.h @@ -1689,4 +1689,32 @@ typedef unsigned int pgtbl_mod_mask; #define MAX_PTRS_PER_P4D PTRS_PER_P4D #endif +/* description of effects of mapping type and prot in current implementation. + * this is due to the limited x86 page protection hardware. The expected + * behavior is in parens: + * + * map_type prot + * PROT_NONE PROT_READ PROT_WRITE PROT_EXEC + * MAP_SHARED r: (no) no r: (yes) yes r: (no) yes r: (no) yes + * w: (no) no w: (no) no w: (yes) yes w: (no) no + * x: (no) no x: (no) yes x: (no) yes x: (yes) yes + * + * MAP_PRIVATE r: (no) no r: (yes) yes r: (no) yes r: (no) yes + * w: (no) no w: (no) no w: (copy) copy w: (no) no + * x: (no) no x: (no) yes x: (no) yes x: (yes) yes + * + * On arm64, PROT_EXEC has the following behaviour for both MAP_SHARED and + * MAP_PRIVATE (with Enhanced PAN supported): + * r: (no) no + * w: (no) no + * x: (yes) yes + */ +#define DECLARE_VM_GET_PAGE_PROT \ +pgprot_t vm_get_page_prot(unsigned long vm_flags) \ +{ \ + return protection_map[vm_flags & \ + (VM_READ | VM_WRITE | VM_EXEC | VM_SHARED)]; \ +} \ +EXPORT_SYMBOL(vm_get_page_prot); + #endif /* _LINUX_PGTABLE_H */ diff --git a/mm/mmap.c b/mm/mmap.c index b01f0280bda2..b46d5e931bb3 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -81,26 +81,6 @@ static void unmap_region(struct mm_struct *mm, struct vm_area_struct *vma, struct vm_area_struct *prev, unsigned long start, unsigned long end); -/* description of effects of mapping type and prot in current implementation. - * this is due to the limited x86 page protection hardware. The expected - * behavior is in parens: - * - * map_type prot - * PROT_NONE PROT_READ PROT_WRITE PROT_EXEC - * MAP_SHARED r: (no) no r: (yes) yes r: (no) yes r: (no) yes - * w: (no) no w: (no) no w: (yes) yes w: (no) no - * x: (no) no x: (no) yes x: (no) yes x: (yes) yes - * - * MAP_PRIVATE r: (no) no r: (yes) yes r: (no) yes r: (no) yes - * w: (no) no w: (no) no w: (copy) copy w: (no) no - * x: (no) no x: (no) yes x: (no) yes x: (yes) yes - * - * On arm64, PROT_EXEC has the following behaviour for both MAP_SHARED and - * MAP_PRIVATE (with Enhanced PAN supported): - * r: (no) no - * w: (no) no - * x: (yes) yes - */ #ifdef __P000 pgprot_t protection_map[16] __ro_after_init = { [VM_NONE] = __P000, @@ -123,11 +103,7 @@ pgprot_t protection_map[16] __ro_after_init = { #endif #ifndef CONFIG_ARCH_HAS_VM_GET_PAGE_PROT -pgprot_t vm_get_page_prot(unsigned long vm_flags) -{ - return protection_map[vm_flags & (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]; -} -EXPORT_SYMBOL(vm_get_page_prot); +DECLARE_VM_GET_PAGE_PROT #endif /* CONFIG_ARCH_HAS_VM_GET_PAGE_PROT */ static pgprot_t vm_pgprot_modify(pgprot_t oldprot, unsigned long vm_flags)