From patchwork Mon Feb 21 06:38:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 12753130 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A8D4C433EF for ; Mon, 21 Feb 2022 06:39:25 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0C2608D000E; Mon, 21 Feb 2022 01:39:25 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 06EEF8D0001; Mon, 21 Feb 2022 01:39:25 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E9FC58D000E; Mon, 21 Feb 2022 01:39:24 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.27]) by kanga.kvack.org (Postfix) with ESMTP id D9DCA8D0001 for ; Mon, 21 Feb 2022 01:39:24 -0500 (EST) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay11.hostedemail.com (Postfix) with ESMTP id 9A48480BCC for ; Mon, 21 Feb 2022 06:39:24 +0000 (UTC) X-FDA: 79165835448.04.0869032 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf12.hostedemail.com (Postfix) with ESMTP id ECA8F40006 for ; Mon, 21 Feb 2022 06:39:23 +0000 (UTC) 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 AEF7D1476; Sun, 20 Feb 2022 22:39:23 -0800 (PST) Received: from p8cg001049571a15.arm.com (unknown [10.163.49.67]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 725763F70D; Sun, 20 Feb 2022 22:39:21 -0800 (PST) From: Anshuman Khandual To: linux-mm@kvack.org, akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, Anshuman Khandual , Christoph Hellwig , linux-arch@vger.kernel.org Subject: [PATCH V2 11/30] mm/mmap: Drop protection_map[] Date: Mon, 21 Feb 2022 12:08:20 +0530 Message-Id: <1645425519-9034-12-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1645425519-9034-1-git-send-email-anshuman.khandual@arm.com> References: <1645425519-9034-1-git-send-email-anshuman.khandual@arm.com> X-Stat-Signature: drw51p7ycrq41rc1ua153scns9tq391w X-Rspam-User: Authentication-Results: imf12.hostedemail.com; dkim=none; spf=pass (imf12.hostedemail.com: domain of anshuman.khandual@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=anshuman.khandual@arm.com; dmarc=pass (policy=none) header.from=arm.com X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: ECA8F40006 X-HE-Tag: 1645425563-18212 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: There are no other users for protection_map[]. Hence just drop this array construct and instead define __vm_get_page_prot() which will provide page protection map based on vm_flags combination switch. Cc: Andrew Morton Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual --- include/linux/mm.h | 6 ----- mm/mmap.c | 61 +++++++++++++++++++++++++++++++--------------- 2 files changed, 41 insertions(+), 26 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 213cc569b192..ff74bd2d7850 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -418,12 +418,6 @@ extern unsigned int kobjsize(const void *objp); #endif #define VM_FLAGS_CLEAR (ARCH_VM_PKEY_FLAGS | VM_ARCH_CLEAR) -/* - * mapping from the currently active vm_flags protection bits (the - * low four bits) to a page protection mask.. - */ -extern pgprot_t protection_map[16]; - /* * The default fault flags that should be used by most of the * arch-specific page fault handlers. diff --git a/mm/mmap.c b/mm/mmap.c index ffd70a0c8ddf..f61f74a61f62 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -102,24 +102,6 @@ static void unmap_region(struct mm_struct *mm, * w: (no) no * x: (yes) yes */ -pgprot_t protection_map[16] __ro_after_init = { - [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 static inline pgprot_t arch_filter_pgprot(pgprot_t prot) @@ -128,10 +110,49 @@ static inline pgprot_t arch_filter_pgprot(pgprot_t prot) } #endif +static inline pgprot_t __vm_get_page_prot(unsigned long vm_flags) +{ + switch (vm_flags & (VM_READ | VM_WRITE | VM_EXEC | VM_SHARED)) { + case VM_NONE: + return __P000; + case VM_READ: + return __P001; + case VM_WRITE: + return __P010; + case VM_READ | VM_WRITE: + return __P011; + case VM_EXEC: + return __P100; + case VM_EXEC | VM_READ: + return __P101; + case VM_EXEC | VM_WRITE: + return __P110; + case VM_EXEC | VM_READ | VM_WRITE: + return __P111; + case VM_SHARED: + return __S000; + case VM_SHARED | VM_READ: + return __S001; + case VM_SHARED | VM_WRITE: + return __S010; + case VM_SHARED | VM_READ | VM_WRITE: + return __S011; + case VM_SHARED | VM_EXEC: + return __S100; + case VM_SHARED | VM_EXEC | VM_READ: + return __S101; + case VM_SHARED | VM_EXEC | VM_WRITE: + return __S110; + case VM_SHARED | VM_EXEC | VM_READ | VM_WRITE: + return __S111; + default: + BUILD_BUG(); + } +} + pgprot_t vm_get_page_prot(unsigned long vm_flags) { - pgprot_t ret = __pgprot(pgprot_val(protection_map[vm_flags & - (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]) | + pgprot_t ret = __pgprot(pgprot_val(__vm_get_page_prot(vm_flags)) | pgprot_val(arch_vm_get_page_prot(vm_flags))); return arch_filter_pgprot(ret);