From patchwork Wed Sep 22 02:58:41 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: disheng.su@gmail.com X-Patchwork-Id: 65394 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 E788FB70EE for ; Wed, 22 Sep 2010 13:04:32 +1000 (EST) Received: from localhost ([127.0.0.1]:33240 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OyFdF-0004W9-0x for incoming@patchwork.ozlabs.org; Tue, 21 Sep 2010 23:04:29 -0400 Received: from [140.186.70.92] (port=47778 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OyFbm-0003tm-Uu for qemu-devel@nongnu.org; Tue, 21 Sep 2010 23:03:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OyFbl-0007t9-CM for qemu-devel@nongnu.org; Tue, 21 Sep 2010 23:02:58 -0400 Received: from mail-pz0-f45.google.com ([209.85.210.45]:58782) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OyFbk-0007sw-Ta for qemu-devel@nongnu.org; Tue, 21 Sep 2010 23:02:57 -0400 Received: by pzk12 with SMTP id 12so24139pzk.4 for ; Tue, 21 Sep 2010 20:02:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:from:to:cc:subject:date :message-id:x-mailer; bh=RcLkjd3/tmHFsFHFzCl8Nmgbbl0ejhO/pWTllQZaaRQ=; b=f5DHp9SoyhTl1qUpBatfad/sF+AvvW/4707aaBfAg3R2MrxyTYvM+qqUgZO5FWnLnq 97dslKmsrxSoFmnu58cYny5Fp0eQtPUT2nnnF+5+OUwOp+jyZ2BiOc6bqH+23a1D6KvI 6He9ynu7zeYdhEFQuUDsqNexN2aHUNSIJiuAc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:subject:date:message-id:x-mailer; b=Bt2ooyp1xAojpn567MabzlgVKRkx4fuZZeZko18BxdtXqOG4wMtGFeaFzRfnl/fsHQ iJuZrIod1dw7YHkzwRm+OdqB6WznvV1PcwdSIMZR73hUsCrB3tuuFsZtovmm0/W+njDd k78Qwdg0J911En/gkaxq4a0VBOX9+eAR3BzjU= Received: by 10.114.36.4 with SMTP id j4mr12903700waj.176.1285124572411; Tue, 21 Sep 2010 20:02:52 -0700 (PDT) Received: from localhost.localdomain (adsl-99-57-184-141.dsl.pltn13.sbcglobal.net [99.57.184.141]) by mx.google.com with ESMTPS id o17sm16683966wal.21.2010.09.21.20.02.50 (version=TLSv1/SSLv3 cipher=RC4-MD5); Tue, 21 Sep 2010 20:02:51 -0700 (PDT) From: disheng.su@gmail.com To: kwolf@redhat.com Date: Tue, 21 Sep 2010 19:58:41 -0700 Message-Id: <1285124321-32556-1-git-send-email-disheng.su@gmail.com> X-Mailer: git-send-email 1.7.2.2 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 2) Cc: qemu-devel@nongnu.org, edison Subject: [Qemu-devel] [PATCH] [V2] Copy snapshots out of QCOW2 disk 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: edison In order to backup snapshots, created from QCOW2 iamge, we want to copy snapshots out of QCOW2 disk to a seperate storage. The following patch adds a new option in "qemu-img": qemu-img convert -f qcow2 -O qcow2 -s snapshot_name src_img bck_img. Right now, it only supports to copy the full snapshot, delta snapshot is on the way. Changes from V1: all the comments from Kevin are addressed: Add read-only checking Fix coding style Change the name from bdrv_snapshot_load to bdrv_snapshot_load_tmp Signed-off-by: Disheng Su --- block.c | 16 ++++++++++++++++ block.h | 2 ++ block/qcow2-snapshot.c | 31 +++++++++++++++++++++++++++++++ block/qcow2.c | 1 + block/qcow2.h | 1 + block_int.h | 2 ++ qemu-img-cmds.hx | 4 ++-- qemu-img.c | 19 ++++++++++++++++++- qemu-img.texi | 4 ++-- 9 files changed, 75 insertions(+), 5 deletions(-) diff --git a/block.c b/block.c index ebbc376..a7a8dfe 100644 --- a/block.c +++ b/block.c @@ -1899,6 +1899,22 @@ int bdrv_snapshot_list(BlockDriverState *bs, return -ENOTSUP; } +int bdrv_snapshot_load_tmp(BlockDriverState *bs, + const char *snapshot_name) +{ + BlockDriver *drv = bs->drv; + if (!drv) { + return -ENOMEDIUM; + } + if (!bs->read_only) { + return -EINVAL; + } + if (drv->bdrv_snapshot_load_tmp) { + return drv->bdrv_snapshot_load_tmp(bs, snapshot_name); + } + return -ENOTSUP; +} + #define NB_SUFFIXES 4 char *get_human_readable_size(char *buf, int buf_size, int64_t size) diff --git a/block.h b/block.h index 5f64380..a4facf2 100644 --- a/block.h +++ b/block.h @@ -211,6 +211,8 @@ int bdrv_snapshot_goto(BlockDriverState *bs, int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id); int bdrv_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_info); +int bdrv_snapshot_load_tmp(BlockDriverState *bs, + const char *snapshot_name); char *bdrv_snapshot_dump(char *buf, int buf_size, QEMUSnapshotInfo *sn); char *get_human_readable_size(char *buf, int buf_size, int64_t size); diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index bbfcaaa..5539510 100644 --- a/block/qcow2-snapshot.c +++ b/block/qcow2-snapshot.c @@ -418,3 +418,34 @@ int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab) return s->nb_snapshots; } +int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name) +{ + int i, snapshot_index, l1_size2; + BDRVQcowState *s = bs->opaque; + QCowSnapshot *sn; + + snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_name); + if (snapshot_index < 0) { + return -ENOENT; + } + + sn = &s->snapshots[snapshot_index]; + s->l1_size = sn->l1_size; + l1_size2 = s->l1_size * sizeof(uint64_t); + if (s->l1_table != NULL) { + qemu_free(s->l1_table); + } + + s->l1_table_offset = sn->l1_table_offset; + s->l1_table = qemu_mallocz(align_offset(l1_size2, 512)); + + if (bdrv_pread(bs->file, sn->l1_table_offset, + s->l1_table, l1_size2) != l1_size2) { + return -1; + } + + for(i = 0;i < s->l1_size; i++) { + be64_to_cpus(&s->l1_table[i]); + } + return 0; +} diff --git a/block/qcow2.c b/block/qcow2.c index ee3481b..4b78dca 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -1379,6 +1379,7 @@ static BlockDriver bdrv_qcow2 = { .bdrv_snapshot_goto = qcow2_snapshot_goto, .bdrv_snapshot_delete = qcow2_snapshot_delete, .bdrv_snapshot_list = qcow2_snapshot_list, + .bdrv_snapshot_load_tmp = qcow2_snapshot_load_tmp, .bdrv_get_info = qcow_get_info, .bdrv_save_vmstate = qcow_save_vmstate, diff --git a/block/qcow2.h b/block/qcow2.h index 356a34a..d1275cd 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -211,6 +211,7 @@ int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info); int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id); int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id); int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab); +int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name); void qcow2_free_snapshots(BlockDriverState *bs); int qcow2_read_snapshots(BlockDriverState *bs); diff --git a/block_int.h b/block_int.h index e8e7156..87e60b8 100644 --- a/block_int.h +++ b/block_int.h @@ -93,6 +93,8 @@ struct BlockDriver { int (*bdrv_snapshot_delete)(BlockDriverState *bs, const char *snapshot_id); int (*bdrv_snapshot_list)(BlockDriverState *bs, QEMUSnapshotInfo **psn_info); + int (*bdrv_snapshot_load_tmp)(BlockDriverState *bs, + const char *snapshot_name); int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi); int (*bdrv_save_vmstate)(BlockDriverState *bs, const uint8_t *buf, diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx index 6d3e5f8..6c7176f 100644 --- a/qemu-img-cmds.hx +++ b/qemu-img-cmds.hx @@ -28,9 +28,9 @@ STEXI ETEXI DEF("convert", img_convert, - "convert [-c] [-f fmt] [-O output_fmt] [-o options] filename [filename2 [...]] output_filename") + "convert [-c] [-f fmt] [-O output_fmt] [-o options] [-s snapshot_name] filename [filename2 [...]] output_filename") STEXI -@item convert [-c] [-f @var{fmt}] [-O @var{output_fmt}] [-o @var{options}] @var{filename} [@var{filename2} [...]] @var{output_filename} +@item convert [-c] [-f @var{fmt}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_name}] @var{filename} [@var{filename2} [...]] @var{output_filename} ETEXI DEF("info", img_info, diff --git a/qemu-img.c b/qemu-img.c index 4e035e4..9b2bc8e 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -646,13 +646,14 @@ static int img_convert(int argc, char **argv) BlockDriverInfo bdi; QEMUOptionParameter *param = NULL, *create_options = NULL; char *options = NULL; + const char *snapshot_name = NULL; fmt = NULL; out_fmt = "raw"; out_baseimg = NULL; flags = 0; for(;;) { - c = getopt(argc, argv, "f:O:B:hce6o:"); + c = getopt(argc, argv, "f:O:B:s:hce6o:"); if (c == -1) break; switch(c) { @@ -680,6 +681,9 @@ static int img_convert(int argc, char **argv) case 'o': options = optarg; break; + case 's': + snapshot_name = optarg; + break; } } @@ -711,6 +715,19 @@ static int img_convert(int argc, char **argv) total_sectors += bs_sectors; } + if (snapshot_name != NULL) { + if (bs_n > 1) { + error("No support for concatenating multiple snapshot\n"); + ret = -1; + goto out; + } + if (bdrv_snapshot_load_tmp(bs[0], snapshot_name) < 0) { + error("Failed to load snapshot\n"); + ret = -1; + goto out; + } + } + /* Find driver and parse its options */ drv = bdrv_find_format(out_fmt); if (!drv) { diff --git a/qemu-img.texi b/qemu-img.texi index c1b1f27..1b90ddb 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -77,9 +77,9 @@ it doesn't need to be specified separately in this case. Commit the changes recorded in @var{filename} in its base image. -@item convert [-c] [-f @var{fmt}] [-O @var{output_fmt}] [-o @var{options}] @var{filename} [@var{filename2} [...]] @var{output_filename} +@item convert [-c] [-f @var{fmt}] [-O @var{output_fmt}] [-o @var{options}] [-s @var{snapshot_name}] @var{filename} [@var{filename2} [...]] @var{output_filename} -Convert the disk image @var{filename} to disk image @var{output_filename} +Convert the disk image @var{filename} or a snapshot @var{snapshot_name} to disk image @var{output_filename} using format @var{output_fmt}. It can be optionally compressed (@code{-c} option) or use any format specific options like encryption (@code{-o} option).