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 51AA2C433EF for ; Mon, 24 Jan 2022 12:58:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242762AbiAXM6B (ORCPT ); Mon, 24 Jan 2022 07:58:01 -0500 Received: from foss.arm.com ([217.140.110.172]:32994 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242240AbiAXM5y (ORCPT ); Mon, 24 Jan 2022 07:57:54 -0500 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 6DECD101E; Mon, 24 Jan 2022 04:57:54 -0800 (PST) Received: from p8cg001049571a15.arm.com (unknown [10.163.43.190]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id A56F13F774; Mon, 24 Jan 2022 04:57:51 -0800 (PST) From: Anshuman Khandual To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, hch@infradead.org, akpm@linux-foundation.org, Anshuman Khandual Subject: [RFC V1 11/31] mm/mmap: Drop protection_map[] Date: Mon, 24 Jan 2022 18:26:48 +0530 Message-Id: <1643029028-12710-12-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1643029028-12710-1-git-send-email-anshuman.khandual@arm.com> References: <1643029028-12710-1-git-send-email-anshuman.khandual@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 e1a84b1e6787..6c0844b99b3e 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 ec403de32dcb..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_READ|VM_WRITE] = __P011, - [VM_EXEC] = __P100, - [VM_EXEC|VM_READ] = __P101, - [VM_EXEC|VM_WRITE] = __P110, - [VM_EXEC|VM_READ|VM_WRITE] = __P111, - [VM_SHARED] = __S000, - [VM_SHARED|VM_READ] = __S001, - [VM_SHARED|VM_WRITE] = __S010, - [VM_SHARED|VM_READ|VM_WRITE] = __S011, - [VM_SHARED|VM_EXEC] = __S100, - [VM_SHARED|VM_READ|VM_EXEC] = __S101, - [VM_SHARED|VM_WRITE|VM_EXEC] = __S110, - [VM_SHARED|VM_READ|VM_WRITE|VM_EXEC] = __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); -- 2.25.1