From patchwork Tue Nov 26 08:56:21 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter Lieven X-Patchwork-Id: 294267 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 9F84A2C00A0 for ; Tue, 26 Nov 2013 20:01:05 +1100 (EST) Received: from localhost ([::1]:57267 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VlEVz-0004a2-3u for incoming@patchwork.ozlabs.org; Tue, 26 Nov 2013 04:01:03 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40572) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VlESK-0007Dc-TU for qemu-devel@nongnu.org; Tue, 26 Nov 2013 03:57:22 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VlESD-0008N3-4j for qemu-devel@nongnu.org; Tue, 26 Nov 2013 03:57:16 -0500 Received: from mx.ipv6.kamp.de ([2a02:248:0:51::16]:38020 helo=mx01.kamp.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VlESC-0008ML-Qg for qemu-devel@nongnu.org; Tue, 26 Nov 2013 03:57:09 -0500 Received: (qmail 14259 invoked by uid 89); 26 Nov 2013 08:57:07 -0000 Received: from [82.141.1.145] by client-16-kamp (envelope-from , uid 89) with qmail-scanner-2010/03/19-MF (clamdscan: 0.98/18162. hbedv: 8.2.12.150/7.11.115.128. spamassassin: 3.3.1. Clear:RC:1(82.141.1.145):SA:0(-1.2/4.0):. Processed in 1.479189 secs); 26 Nov 2013 08:57:07 -0000 Received: from ns.kamp-intra.net (HELO dns.kamp-intra.net) ([82.141.1.145]) by mx01.kamp.de with SMTP; 26 Nov 2013 08:57:06 -0000 X-GL_Whitelist: yes Received: from lieven-pc.kamp-intra.net (lieven-pc.kamp-intra.net [172.21.12.60]) by dns.kamp-intra.net (Postfix) with ESMTP id 51E90206AE; Tue, 26 Nov 2013 09:56:04 +0100 (CET) Received: by lieven-pc.kamp-intra.net (Postfix, from userid 1000) id 2E6F95FD57; Tue, 26 Nov 2013 09:56:29 +0100 (CET) From: Peter Lieven To: qemu-devel@nongnu.org Date: Tue, 26 Nov 2013 09:56:21 +0100 Message-Id: <1385456183-24840-8-git-send-email-pl@kamp.de> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1385456183-24840-1-git-send-email-pl@kamp.de> References: <1385456183-24840-1-git-send-email-pl@kamp.de> X-detected-operating-system: by eggs.gnu.org: Error: Malformed IPv6 address (bad octet value). X-Received-From: 2a02:248:0:51::16 Cc: kwolf@redhat.com, pbonzini@redhat.com, Peter Lieven , stefanha@redhat.com Subject: [Qemu-devel] [PATCHv2 1.8 7/9] qemu-img: round down request length to an aligned sector X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org this patch shortens requests to end at an aligned sector so that the next request starts aligned. Signed-off-by: Peter Lieven Reviewed-by: Paolo Bonzini --- qemu-img.c | 30 ++++++++++++++++++++---------- 1 file changed, 20 insertions(+), 10 deletions(-) diff --git a/qemu-img.c b/qemu-img.c index b076d44..1421f0f 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1124,8 +1124,7 @@ out3: static int img_convert(int argc, char **argv) { - int c, n, n1, bs_n, bs_i, compress, cluster_size, - cluster_sectors, skip_create; + int c, n, n1, bs_n, bs_i, compress, cluster_sectors, skip_create; int64_t ret = 0; int progress = 0, flags; const char *fmt, *out_fmt, *cache, *out_baseimg, *out_filename; @@ -1397,19 +1396,21 @@ static int img_convert(int argc, char **argv) } } + cluster_sectors = 0; + ret = bdrv_get_info(out_bs, &bdi); + if (ret < 0 && compress) { + error_report("could not get block driver info"); + goto out; + } else { + cluster_sectors = bdi.cluster_size / BDRV_SECTOR_SIZE; + } + if (compress) { - ret = bdrv_get_info(out_bs, &bdi); - if (ret < 0) { - error_report("could not get block driver info"); - goto out; - } - cluster_size = bdi.cluster_size; - if (cluster_size <= 0 || cluster_size > bufsectors * BDRV_SECTOR_SIZE) { + if (cluster_sectors <= 0 || cluster_sectors > bufsectors) { error_report("invalid cluster size"); ret = -1; goto out; } - cluster_sectors = cluster_size >> 9; sector_num = 0; nb_sectors = total_sectors; @@ -1547,6 +1548,15 @@ static int img_convert(int argc, char **argv) n = nb_sectors; } + /* round down request length to an aligned sector */ + if (cluster_sectors > 0 && n >= cluster_sectors) { + int64_t next_aligned_sector = (sector_num + n); + next_aligned_sector -= next_aligned_sector % cluster_sectors; + if (sector_num + n > next_aligned_sector) { + n = next_aligned_sector - sector_num; + } + } + if (n > bs_offset + bs_sectors - sector_num) { n = bs_offset + bs_sectors - sector_num; }