Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262369AbVDGBTQ (ORCPT ); Wed, 6 Apr 2005 21:19:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262378AbVDGBTG (ORCPT ); Wed, 6 Apr 2005 21:19:06 -0400 Received: from bay-bridge.veritas.com ([143.127.3.10]:49001 "EHLO MTVMIME03.enterprise.veritas.com") by vger.kernel.org with ESMTP id S262369AbVDGBQa (ORCPT ); Wed, 6 Apr 2005 21:16:30 -0400 Date: Thu, 7 Apr 2005 02:16:37 +0100 (BST) From: Hugh Dickins X-X-Sender: hugh@goblin.wat.veritas.com To: Andrew Morton cc: Nick Piggin , Russell King , Ian Molton , linux-kernel@vger.kernel.org Subject: [PATCH 4/6] freepgt2: arm26 FIRST_USER_ADDRESS PAGE_SIZE In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2444 Lines: 64 ARM26 define FIRST_USER_ADDRESS as PAGE_SIZE (beyond the machine vectors when they are mapped low), and use that definition in place of locally defined MIN_MAP_ADDR. Previously, ARM26 permitted user mappings at 0 if the machine vectors were mapped high; but that's inconsistent with ARM, and FIRST_USER_ADDRESS would then have to be determined at runtime. Let's fix it at PAGE_SIZE throughout the architecture. Signed-off-by: Hugh Dickins --- arch/arm26/kernel/sys_arm.c | 9 ++++----- include/asm-arm26/pgtable.h | 7 +++++++ 2 files changed, 11 insertions(+), 5 deletions(-) --- 2.6.12-rc2-mm1/arch/arm26/kernel/sys_arm.c 2005-03-02 07:38:58.000000000 +0000 +++ linux/arch/arm26/kernel/sys_arm.c 2005-04-05 18:59:00.000000000 +0100 @@ -64,10 +64,10 @@ inline long do_mmap2( flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE); /* - * If we are doing a fixed mapping, and address < PAGE_SIZE, + * If we are doing a fixed mapping, and address < FIRST_USER_ADDRESS, * then deny it. */ - if (flags & MAP_FIXED && addr < PAGE_SIZE && vectors_base() == 0) + if (flags & MAP_FIXED && addr < FIRST_USER_ADDRESS) goto out; error = -EBADF; @@ -121,11 +121,10 @@ sys_arm_mremap(unsigned long addr, unsig unsigned long ret = -EINVAL; /* - * If we are doing a fixed mapping, and address < PAGE_SIZE, + * If we are doing a fixed mapping, and address < FIRST_USER_ADDRESS, * then deny it. */ - if (flags & MREMAP_FIXED && new_addr < PAGE_SIZE && - vectors_base() == 0) + if (flags & MREMAP_FIXED && new_addr < FIRST_USER_ADDRESS) goto out; down_write(¤t->mm->mmap_sem); --- 2.6.12-rc2-mm1/include/asm-arm26/pgtable.h 2005-04-05 15:20:55.000000000 +0100 +++ linux/include/asm-arm26/pgtable.h 2005-04-05 18:59:00.000000000 +0100 @@ -62,6 +62,13 @@ #define PTRS_PER_PMD 1 #define PTRS_PER_PTE 32 +/* + * This is the lowest virtual address we can permit any user space + * mapping to be mapped at. This is particularly important for + * non-high vector CPUs. + */ +#define FIRST_USER_ADDRESS PAGE_SIZE + #define FIRST_USER_PGD_NR 1 #define USER_PTRS_PER_PGD ((TASK_SIZE/PGD_SIZE) - FIRST_USER_PGD_NR) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/