From patchwork Wed Feb 7 12:04:10 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 10205033 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 7CC54602D8 for ; Wed, 7 Feb 2018 12:08:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5DD3328F29 for ; Wed, 7 Feb 2018 12:08:15 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5134628F2B; Wed, 7 Feb 2018 12:08:15 +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 B6BBF28F29 for ; Wed, 7 Feb 2018 12:08:14 +0000 (UTC) Received: from localhost ([::1]:56935 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ejOWL-0003d1-Cl for patchwork-qemu-devel@patchwork.kernel.org; Wed, 07 Feb 2018 07:08:13 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:50076) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ejOSV-0008Sv-5X for qemu-devel@nongnu.org; Wed, 07 Feb 2018 07:04:16 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ejOSP-0003v8-4S for qemu-devel@nongnu.org; Wed, 07 Feb 2018 07:04:15 -0500 Received: from mail.ispras.ru ([83.149.199.45]:47334) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ejOSO-0003u2-P5 for qemu-devel@nongnu.org; Wed, 07 Feb 2018 07:04:09 -0500 Received: from [127.0.1.1] (unknown [85.142.117.226]) by mail.ispras.ru (Postfix) with ESMTPSA id D379C54008B; Wed, 7 Feb 2018 15:04:07 +0300 (MSK) From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Wed, 07 Feb 2018 15:04:10 +0300 Message-ID: <20180207120410.5389.80460.stgit@pasha-VirtualBox> In-Reply-To: <20180207120353.5389.54531.stgit@pasha-VirtualBox> References: <20180207120353.5389.54531.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] [RFC PATCH v6 03/20] 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 | 65 +++++++++++++++++++++++++++++++++++++++++++++++++++++ stubs/replay.c | 1 + vl.c | 2 +- 3 files changed, 67 insertions(+), 1 deletion(-) diff --git a/block/blkreplay.c b/block/blkreplay.c index 4c58bd2..2bef4d6 100755 --- a/block/blkreplay.c +++ b/block/blkreplay.c @@ -14,12 +14,69 @@ #include "block/block_int.h" #include "sysemu/replay.h" #include "qapi/error.h" +#include "qapi/qmp/qstring.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 +92,14 @@ 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 e517a8d..42f6ba3 100644 --- a/vl.c +++ b/vl.c @@ -4533,7 +4533,7 @@ 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); }