From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marco Stornelli Subject: [PATCH 14/16 v2] pramfs: write protection Date: Sat, 06 Nov 2010 10:00:55 +0100 Message-ID: <4CD51947.4040302@gmail.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from :user-agent:mime-version:to:cc:subject:content-type :content-transfer-encoding; bh=yQS3R+dUhEyP0fbwCXqNRrZlU4b9fMeFsezPiaUVNsQ=; b=h5NCbqk2NqU89LMuC9o9WGqHWN3QvUDIRmj6dL0N4qvyaD58pF1ddwt9eL7r24OL1D lyHewzTKK64aN60OppAQOTWvW2DaZvqoCk0nBD9Q/2unoo2U4P7opvbIn6jmvMfWOFCk K7HKhdP69rxHC1dDqld2H/AslWWV+C6lBdF9A= Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Linux Kernel Cc: Linux Embedded , Linux FS Devel , Tim Bird , Andrew Morton From: Marco Stornelli Memory write protection. Signed-off-by: Marco Stornelli --- diff -Nurp linux-2.6.36-orig/fs/pramfs/wprotect.c linux-2.6.36/fs/pramfs/wprotect.c --- linux-2.6.36-orig/fs/pramfs/wprotect.c 1970-01-01 01:00:00.000000000 +0100 +++ linux-2.6.36/fs/pramfs/wprotect.c 2010-10-30 11:59:54.000000000 +0200 @@ -0,0 +1,41 @@ +/* + * FILE NAME fs/pramfs/wprotect.c + * + * BRIEF DESCRIPTION + * + * Write protection for the filesystem pages. + * + * Copyright 2009-2010 Marco Stornelli + * Copyright 2003 Sony Corporation + * Copyright 2003 Matsushita Electric Industrial Co., Ltd. + * 2003-2004 (c) MontaVista Software, Inc. , Steve Longerbeam + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include +#include +#include +#include +#include "pram.h" + +void pram_writeable(void *vaddr, unsigned long size, int rw) +{ + int ret = 0; + unsigned long nrpages = size >> PAGE_SHIFT; + unsigned long addr = (unsigned long)vaddr; + + /* Page aligned */ + addr &= PAGE_MASK; + + if (size & (PAGE_SIZE - 1)) + nrpages++; + + if (rw) + ret = set_memory_rw(addr, nrpages); + else + ret = set_memory_ro(addr, nrpages); + + BUG_ON(ret); +}