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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 72A2EC433F5 for ; Mon, 4 Apr 2022 03:18:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377002AbiDDDUd (ORCPT ); Sun, 3 Apr 2022 23:20:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60274 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1376986AbiDDDU0 (ORCPT ); Sun, 3 Apr 2022 23:20:26 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E42F1B24 for ; Sun, 3 Apr 2022 20:18:28 -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 41A9A1FB; Sun, 3 Apr 2022 20:18:28 -0700 (PDT) Received: from a077893.arm.com (unknown [10.163.36.163]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 4222D3F73B; Sun, 3 Apr 2022 20:18:25 -0700 (PDT) From: Anshuman Khandual To: linux-mm@kvack.org Cc: Anshuman Khandual , linux-kernel@vger.kernel.org, Christoph Hellwig , Andrew Morton Subject: [PATCH 2/2] mm/mmap: Clarify protection_map[] indices Date: Mon, 4 Apr 2022 08:48:40 +0530 Message-Id: <20220404031840.588321-3-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220404031840.588321-1-anshuman.khandual@arm.com> References: <20220404031840.588321-1-anshuman.khandual@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 3aa839f81e63..4b8ee3fd03ad 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 -- 2.25.1