From patchwork Fri Apr 30 14:00:35 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 51348 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 A4742B7D19 for ; Sat, 1 May 2010 00:45:50 +1000 (EST) Received: from localhost ([127.0.0.1]:41646 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1O7rTP-0004bn-CO for incoming@patchwork.ozlabs.org; Fri, 30 Apr 2010 10:45:47 -0400 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1O7r6B-0005hB-6Q for qemu-devel@nongnu.org; Fri, 30 Apr 2010 10:21:47 -0400 Received: from [140.186.70.92] (port=34496 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1O7r68-0005ew-RG for qemu-devel@nongnu.org; Fri, 30 Apr 2010 10:21:46 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1O7r62-00038r-9V for qemu-devel@nongnu.org; Fri, 30 Apr 2010 10:21:40 -0400 Received: from mx1.redhat.com ([209.132.183.28]:26099) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1O7r61-00038H-6g for qemu-devel@nongnu.org; Fri, 30 Apr 2010 10:21:38 -0400 Received: from int-mx04.intmail.prod.int.phx2.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.17]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o3UE2DKm009079 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Fri, 30 Apr 2010 10:02:13 -0400 Received: from localhost.localdomain (vpn1-6-55.ams2.redhat.com [10.36.6.55]) by int-mx04.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id o3UE14sC007196; Fri, 30 Apr 2010 10:02:11 -0400 From: Kevin Wolf To: aliguori@linux.vnet.ibm.com Date: Fri, 30 Apr 2010 16:00:35 +0200 Message-Id: <1272636040-17374-14-git-send-email-kwolf@redhat.com> In-Reply-To: <1272636040-17374-1-git-send-email-kwolf@redhat.com> References: <1272636040-17374-1-git-send-email-kwolf@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.17 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 13/18] qemu-img: Add 'resize' command to grow/shrink disk images 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 Hajnoczi This patch adds a 'resize' command to grow/shrink disk images. This allows changing the size of disk images without copying to a new image file. Currently only raw files support resize. Signed-off-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- qemu-img-cmds.hx | 6 +++ qemu-img.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ qemu-img.texi | 12 +++++++ 3 files changed, 110 insertions(+), 0 deletions(-) diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx index f96876a..c079019 100644 --- a/qemu-img-cmds.hx +++ b/qemu-img-cmds.hx @@ -49,5 +49,11 @@ DEF("rebase", img_rebase, "rebase [-f fmt] [-u] -b backing_file [-F backing_fmt] filename") STEXI @item rebase [-f @var{fmt}] [-u] -b @var{backing_file} [-F @var{backing_fmt}] @var{filename} +ETEXI + +DEF("resize", img_resize, + "resize filename [+ | -]size") +STEXI +@item rebase @var{filename} [+ | -]@var{size} @end table ETEXI diff --git a/qemu-img.c b/qemu-img.c index 74311a5..c21d999 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1225,6 +1225,98 @@ static int img_rebase(int argc, char **argv) return 0; } +static int img_resize(int argc, char **argv) +{ + int c, ret, relative; + const char *filename, *fmt, *size; + int64_t n, total_size; + BlockDriverState *bs; + QEMUOptionParameter *param; + QEMUOptionParameter resize_options[] = { + { + .name = BLOCK_OPT_SIZE, + .type = OPT_SIZE, + .help = "Virtual disk size" + }, + { NULL } + }; + + fmt = NULL; + for(;;) { + c = getopt(argc, argv, "f:h"); + if (c == -1) { + break; + } + switch(c) { + case 'h': + help(); + break; + case 'f': + fmt = optarg; + break; + } + } + if (optind + 1 >= argc) { + help(); + } + filename = argv[optind++]; + size = argv[optind++]; + + /* Choose grow, shrink, or absolute resize mode */ + switch (size[0]) { + case '+': + relative = 1; + size++; + break; + case '-': + relative = -1; + size++; + break; + default: + relative = 0; + break; + } + + /* Parse size */ + param = parse_option_parameters("", resize_options, NULL); + if (set_option_parameter(param, BLOCK_OPT_SIZE, size)) { + /* Error message already printed when size parsing fails */ + exit(1); + } + n = get_option_parameter(param, BLOCK_OPT_SIZE)->value.n; + free_option_parameters(param); + + bs = bdrv_new_open(filename, fmt, BDRV_O_FLAGS | BDRV_O_RDWR); + + if (relative) { + total_size = bdrv_getlength(bs) + n * relative; + } else { + total_size = n; + } + if (total_size <= 0) { + error("New image size must be positive"); + } + + ret = bdrv_truncate(bs, total_size); + switch (ret) { + case 0: + printf("Image resized.\n"); + break; + case -ENOTSUP: + error("This image format does not support resize"); + break; + case -EACCES: + error("Image is read-only"); + break; + default: + error("Error resizing image (%d)", -ret); + break; + } + + bdrv_delete(bs); + return 0; +} + static const img_cmd_t img_cmds[] = { #define DEF(option, callback, arg_string) \ { option, callback }, diff --git a/qemu-img.texi b/qemu-img.texi index ac97854..c1b1f27 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -106,6 +106,18 @@ they are displayed too. @item snapshot [-l | -a @var{snapshot} | -c @var{snapshot} | -d @var{snapshot} ] @var{filename} List, apply, create or delete snapshots in image @var{filename}. + +@item resize @var{filename} [+ | -]@var{size} + +Change the disk image as if it had been created with @var{size}. + +Before using this command to shrink a disk image, you MUST use file system and +partitioning tools inside the VM to reduce allocated file systems and partition +sizes accordingly. Failure to do so will result in data loss! + +After using this command to grow a disk image, you must use file system and +partitioning tools inside the VM to actually begin using the new space on the +device. @end table Supported image file formats: