From patchwork Tue Feb 27 09:51:52 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 10244585 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 6F82960362 for ; Tue, 27 Feb 2018 09:53:19 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5DED92A1E7 for ; Tue, 27 Feb 2018 09:53:19 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 51FA42A1FD; Tue, 27 Feb 2018 09:53:19 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id AF7A12A1E7 for ; Tue, 27 Feb 2018 09:53:18 +0000 (UTC) Received: from localhost ([::1]:35813 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eqbwj-0001nw-KQ for patchwork-qemu-devel@patchwork.kernel.org; Tue, 27 Feb 2018 04:53:17 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39484) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eqbvN-0000Wm-Cb for qemu-devel@nongnu.org; Tue, 27 Feb 2018 04:51:54 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eqbvM-0004Yy-EA for qemu-devel@nongnu.org; Tue, 27 Feb 2018 04:51:53 -0500 Received: from mail.ispras.ru ([83.149.199.45]:57230) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eqbvM-0004Yc-0f for qemu-devel@nongnu.org; Tue, 27 Feb 2018 04:51:52 -0500 Received: from [127.0.1.1] (unknown [85.142.117.226]) by mail.ispras.ru (Postfix) with ESMTPSA id 0A41A54006A; Tue, 27 Feb 2018 12:51:51 +0300 (MSK) From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Tue, 27 Feb 2018 12:51:52 +0300 Message-ID: <20180227095152.1060.10071.stgit@pasha-VirtualBox> In-Reply-To: <20180227095135.1060.36549.stgit@pasha-VirtualBox> References: <20180227095135.1060.36549.stgit@pasha-VirtualBox> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 83.149.199.45 Subject: [Qemu-devel] [PATCH v7 03/22] blkreplay: create temporary overlay for underlaying devices X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, peter.maydell@linaro.org, war2jordan@live.com, pavel.dovgaluk@ispras.ru, quintela@redhat.com, ciro.santilli@gmail.com, jasowang@redhat.com, mst@redhat.com, zuban32s@gmail.com, maria.klimushenkova@ispras.ru, dovgaluk@ispras.ru, kraxel@redhat.com, boost.lists@gmail.com, thomas.dullien@googlemail.com, pbonzini@redhat.com, alex.bennee@linaro.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Pavel Dovgalyuk This patch allows using '-snapshot' behavior in record/replay mode. blkreplay layer creates temporary overlays on top of underlaying disk images. It is needed, because creating an overlay over blkreplay breaks the determinism. This patch creates similar temporary overlay (when it is needed) under the blkreplay driver. Therefore all block operations are controlled by blkreplay. Signed-off-by: Pavel Dovgalyuk --- block/blkreplay.c | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++ stubs/replay.c | 1 + vl.c | 2 +- 3 files changed, 69 insertions(+), 1 deletion(-) diff --git a/block/blkreplay.c b/block/blkreplay.c index 4c58bd2..2b68ac3 100755 --- a/block/blkreplay.c +++ b/block/blkreplay.c @@ -14,12 +14,71 @@ #include "block/block_int.h" #include "sysemu/replay.h" #include "qapi/error.h" +#include "qapi/qmp/qstring.h" +#include "qapi/qmp/qdict.h" +#include "qemu/option.h" typedef struct Request { Coroutine *co; QEMUBH *bh; } Request; +static BlockDriverState *blkreplay_append_snapshot(BlockDriverState *bs, + Error **errp) +{ + int ret; + BlockDriverState *bs_snapshot; + int64_t total_size; + QemuOpts *opts = NULL; + char tmp_filename[PATH_MAX + 1]; + QDict *snapshot_options = qdict_new(); + + /* Prepare options QDict for the overlay file */ + qdict_put(snapshot_options, "file.driver", qstring_from_str("file")); + qdict_put(snapshot_options, "driver", qstring_from_str("qcow2")); + + /* Create temporary file */ + ret = get_tmp_filename(tmp_filename, PATH_MAX + 1); + if (ret < 0) { + error_setg_errno(errp, -ret, "Could not get temporary filename"); + goto out; + } + qdict_put(snapshot_options, "file.filename", + qstring_from_str(tmp_filename)); + + /* Get the required size from the image */ + total_size = bdrv_getlength(bs); + if (total_size < 0) { + error_setg_errno(errp, -total_size, "Could not get image size"); + goto out; + } + + opts = qemu_opts_create(bdrv_qcow2.create_opts, NULL, 0, &error_abort); + qemu_opt_set_number(opts, BLOCK_OPT_SIZE, total_size, &error_abort); + ret = bdrv_create(&bdrv_qcow2, tmp_filename, opts, errp); + qemu_opts_del(opts); + if (ret < 0) { + error_prepend(errp, "Could not create temporary overlay '%s': ", + tmp_filename); + goto out; + } + + bs_snapshot = bdrv_open(NULL, NULL, snapshot_options, + BDRV_O_RDWR | BDRV_O_TEMPORARY, errp); + snapshot_options = NULL; + if (!bs_snapshot) { + goto out; + } + + bdrv_append(bs_snapshot, bs, errp); + + return bs_snapshot; + +out: + QDECREF(snapshot_options); + return NULL; +} + static int blkreplay_open(BlockDriverState *bs, QDict *options, int flags, Error **errp) { @@ -35,6 +94,14 @@ static int blkreplay_open(BlockDriverState *bs, QDict *options, int flags, goto fail; } + /* Add temporary snapshot to preserve the image */ + if (!replay_snapshot + && !blkreplay_append_snapshot(bs->file->bs, &local_err)) { + ret = -EINVAL; + error_propagate(errp, local_err); + goto fail; + } + ret = 0; fail: return ret; diff --git a/stubs/replay.c b/stubs/replay.c index 9c8aa48..9991ee5 100644 --- a/stubs/replay.c +++ b/stubs/replay.c @@ -3,6 +3,7 @@ #include "sysemu/sysemu.h" ReplayMode replay_mode; +char *replay_snapshot; int64_t replay_save_clock(unsigned int kind, int64_t clock) { diff --git a/vl.c b/vl.c index 9e7235d..d260a06 100644 --- a/vl.c +++ b/vl.c @@ -4523,7 +4523,7 @@ int main(int argc, char **argv, char **envp) qapi_free_BlockdevOptions(bdo->bdo); g_free(bdo); } - if (snapshot || replay_mode != REPLAY_MODE_NONE) { + if (snapshot) { qemu_opts_foreach(qemu_find_opts("drive"), drive_enable_snapshot, NULL, NULL); }