From patchwork Fri May 14 17:10:48 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 52645 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id EC8F7B7E5B for ; Sat, 15 May 2010 03:33:58 +1000 (EST) Received: from localhost ([127.0.0.1]:41636 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OCylo-0006aO-4G for incoming@patchwork.ozlabs.org; Fri, 14 May 2010 13:33:56 -0400 Received: from [140.186.70.92] (port=41371 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OCyQV-0000du-FM for qemu-devel@nongnu.org; Fri, 14 May 2010 13:11:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OCyQN-0001vV-Tm for qemu-devel@nongnu.org; Fri, 14 May 2010 13:11:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:25891) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OCyQN-0001v6-Lp for qemu-devel@nongnu.org; Fri, 14 May 2010 13:11:47 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o4EHBkbk032138 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 14 May 2010 13:11:46 -0400 Received: from localhost.localdomain (vpn1-7-82.ams2.redhat.com [10.36.7.82]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o4EHBFWi004751; Fri, 14 May 2010 13:11:44 -0400 From: Kevin Wolf To: anthony@codemonkey.ws Date: Fri, 14 May 2010 19:10:48 +0200 Message-Id: <1273857055-26715-15-git-send-email-kwolf@redhat.com> In-Reply-To: <1273857055-26715-1-git-send-email-kwolf@redhat.com> References: <1273857055-26715-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. Cc: kwolf@redhat.com, qemu-devel@nongnu.org Subject: [Qemu-devel] [PATCH 14/21] block/vpc: Fix conversion from size to disk geometry X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org From: Stefan Weil The VHD algorithm calculates a disk geometry which is usually smaller than the requested size. QEMU tried to round up but failed for certain sizes: qemu-img create -f vpc disk.vpc 9437184 would create an image with 9435136 bytes (which is too small for qemu-img convert). Instead of hacking the geometry algorithm, the patch increases the number of sectors until we get enough sectors. Cc: Kevin Wolf Signed-off-by: Stefan Weil Signed-off-by: Kevin Wolf --- block/vpc.c | 21 ++++++++++++--------- 1 files changed, 12 insertions(+), 9 deletions(-) diff --git a/block/vpc.c b/block/vpc.c index f94e469..214e9d1 100644 --- a/block/vpc.c +++ b/block/vpc.c @@ -463,9 +463,7 @@ static int calculate_geometry(int64_t total_sectors, uint16_t* cyls, } } - // Note: Rounding up deviates from the Virtual PC behaviour - // However, we need this to avoid truncating images in qemu-img convert - *cyls = (cyls_times_heads + *heads - 1) / *heads; + *cyls = cyls_times_heads / *heads; return 0; } @@ -477,9 +475,9 @@ static int vpc_create(const char *filename, QEMUOptionParameter *options) struct vhd_dyndisk_header* dyndisk_header = (struct vhd_dyndisk_header*) buf; int fd, i; - uint16_t cyls; - uint8_t heads; - uint8_t secs_per_cyl; + uint16_t cyls = 0; + uint8_t heads = 0; + uint8_t secs_per_cyl = 0; size_t block_size, num_bat_entries; int64_t total_sectors = 0; @@ -496,9 +494,14 @@ static int vpc_create(const char *filename, QEMUOptionParameter *options) if (fd < 0) return -EIO; - // Calculate matching total_size and geometry - if (calculate_geometry(total_sectors, &cyls, &heads, &secs_per_cyl)) - return -EFBIG; + /* Calculate matching total_size and geometry. Increase the number of + sectors requested until we get enough (or fail). */ + for (i = 0; total_sectors > (int64_t)cyls * heads * secs_per_cyl; i++) { + if (calculate_geometry(total_sectors + i, + &cyls, &heads, &secs_per_cyl)) { + return -EFBIG; + } + } total_sectors = (int64_t) cyls * heads * secs_per_cyl; // Prepare the Hard Disk Footer