From patchwork Mon Jun 6 16:58:47 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell King X-Patchwork-Id: 9158821 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 74A5260759 for ; Mon, 6 Jun 2016 17:01:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 660052833E for ; Mon, 6 Jun 2016 17:01:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5B06E2834D; Mon, 6 Jun 2016 17:01:17 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 1C07B2833E for ; Mon, 6 Jun 2016 17:01:17 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1b9xs9-0001Xf-Up; Mon, 06 Jun 2016 16:59:29 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1b9xs2-0001VZ-SD for linux-arm-kernel@lists.infradead.org; Mon, 06 Jun 2016 16:59:27 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2014; h=Date:Sender:Message-Id:Content-Type:Content-Transfer-Encoding:MIME-Version:Subject:Cc:To:From:References:In-Reply-To; bh=zNnCEF4Eu1ckU3aBdy1/uijTaywt+6cnWKSB0+qkOUQ=; b=IF5+K11y6H52cjtXJ4VW3l5PDgKrQxcO/Xu38u4JCn8b6s5kL3lqzkz92k8p6STWju0Ig3d+BBnUW4MkSsI1yDWSmiFGgh576iodKGG9Bu5Rdjmm70pn/4qRAiKfVHhxdJ+mWdMNEwHSp3DxQxQQw1hT5ifQm+YUyOPnr12XTiU=; Received: from [fd8f:7570:feb6:1:b4eb:e902:622d:f2f0] (port=37630 helo=e0050434b2927.dyn.armlinux.org.uk) by pandora.armlinux.org.uk with esmtpsa (TLSv1:DHE-RSA-AES128-SHA:128) (Exim 4.82_1-5b7a7c0-XX) (envelope-from ) id 1b9xrV-0000EC-T7; Mon, 06 Jun 2016 17:58:50 +0100 Received: from rmk by e0050434b2927.dyn.armlinux.org.uk with local (Exim 4.82) (envelope-from ) id 1b9xrT-0003rV-HE; Mon, 06 Jun 2016 17:58:47 +0100 In-Reply-To: <20160606164129.GM1041@n2100.armlinux.org.uk> References: <20160606164129.GM1041@n2100.armlinux.org.uk> From: Russell King To: kexec@lists.infradead.org,linux-arm-kernel@lists.infradead.org Subject: [PATCH kexec-tools v2 01/32] kdump: mmap() and munmap() only work on page-aligned quantites MIME-Version: 1.0 Content-Disposition: inline Message-Id: Date: Mon, 06 Jun 2016 17:58:47 +0100 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160606_095923_686472_2C3FF8F7 X-CRM114-Status: GOOD ( 11.12 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pratyush Anand , Baoquan He Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The man page for mmap() and munmap() says that mmap() and munmap() only works for page-aligned addresses, sizes and offsets. Arrange to give these interfaces what they want. Reviewed-by: Pratyush Anand Signed-off-by: Russell King --- kdump/kdump.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/kdump/kdump.c b/kdump/kdump.c index 821ee7c..3247a54 100644 --- a/kdump/kdump.c +++ b/kdump/kdump.c @@ -25,22 +25,35 @@ #define MAP_WINDOW_SIZE (64*1024*1024) #define DEV_MEM "/dev/mem" +#define ALIGN_MASK(x,y) (((x) + (y)) & ~(y)) +#define ALIGN(x,y) ALIGN_MASK(x, (y) - 1) + static void *map_addr(int fd, unsigned long size, off_t offset) { + unsigned long page_size = getpagesize(); + unsigned long map_offset = offset & (page_size - 1); + size_t len = ALIGN(size + map_offset, page_size); void *result; - result = mmap(0, size, PROT_READ, MAP_SHARED, fd, offset); + + result = mmap(0, len, PROT_READ, MAP_SHARED, fd, offset - map_offset); if (result == MAP_FAILED) { fprintf(stderr, "Cannot mmap " DEV_MEM " offset: %llu size: %lu: %s\n", (unsigned long long)offset, size, strerror(errno)); exit(5); } - return result; + return result + map_offset; } static void unmap_addr(void *addr, unsigned long size) { + unsigned long page_size = getpagesize(); + unsigned long map_offset = (uintptr_t)addr & (page_size - 1); + size_t len = ALIGN(size + map_offset, page_size); int ret; - ret = munmap(addr, size); + + addr -= map_offset; + + ret = munmap(addr, len); if (ret < 0) { fprintf(stderr, "munmap failed: %s\n", strerror(errno));