From patchwork Mon Feb 28 10:47:25 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 12762736 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 B1808C4167B for ; Mon, 28 Feb 2022 10:49:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234907AbiB1Kt5 (ORCPT ); Mon, 28 Feb 2022 05:49:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44688 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234974AbiB1Ktk (ORCPT ); Mon, 28 Feb 2022 05:49:40 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 91E0D5BD18; Mon, 28 Feb 2022 02:49:01 -0800 (PST) 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 3DC2A1063; Mon, 28 Feb 2022 02:49:01 -0800 (PST) Received: from p8cg001049571a15.arm.com (unknown [10.163.47.185]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id C396D3F73D; Mon, 28 Feb 2022 02:48:52 -0800 (PST) From: Anshuman Khandual To: linux-mm@kvack.org, akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, geert@linux-m68k.org, Anshuman Khandual , Christoph Hellwig , linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, sparclinux@vger.kernel.org, linux-mips@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-s390@vger.kernel.org, linux-riscv@lists.infradead.org, linux-alpha@vger.kernel.org, linux-sh@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-csky@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-parisc@vger.kernel.org, openrisc@lists.librecores.org, linux-um@lists.infradead.org, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-arch@vger.kernel.org Subject: [PATCH V3 02/30] mm/mmap: Clarify protection_map[] indices Date: Mon, 28 Feb 2022 16:17:25 +0530 Message-Id: <1646045273-9343-3-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1646045273-9343-1-git-send-email-anshuman.khandual@arm.com> References: <1646045273-9343-1-git-send-email-anshuman.khandual@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org protection_map[] maps vm_flags access combinations into page protection value as defined by the platform via __PXXX and __SXXX macros. The array indices in protection_map[], represents vm_flags access combinations but it's not very intuitive to derive. This makes it clear and explicit. Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Christoph Hellwig Signed-off-by: Anshuman Khandual --- mm/mmap.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index d445c1b9d606..34000a7d7efa 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -102,8 +102,22 @@ static void unmap_region(struct mm_struct *mm, * x: (yes) yes */ pgprot_t protection_map[16] __ro_after_init = { - __P000, __P001, __P010, __P011, __P100, __P101, __P110, __P111, - __S000, __S001, __S010, __S011, __S100, __S101, __S110, __S111 + [VM_NONE] = __P000, + [VM_READ] = __P001, + [VM_WRITE] = __P010, + [VM_WRITE | VM_READ] = __P011, + [VM_EXEC] = __P100, + [VM_EXEC | VM_READ] = __P101, + [VM_EXEC | VM_WRITE] = __P110, + [VM_EXEC | VM_WRITE | VM_READ] = __P111, + [VM_SHARED] = __S000, + [VM_SHARED | VM_READ] = __S001, + [VM_SHARED | VM_WRITE] = __S010, + [VM_SHARED | VM_WRITE | VM_READ] = __S011, + [VM_SHARED | VM_EXEC] = __S100, + [VM_SHARED | VM_EXEC | VM_READ] = __S101, + [VM_SHARED | VM_EXEC | VM_WRITE] = __S110, + [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = __S111 }; #ifndef CONFIG_ARCH_HAS_FILTER_PGPROT