From nobody Thu Oct 30 01:33:45 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1510648060041920.6717702543536; Tue, 14 Nov 2017 00:27:40 -0800 (PST) Received: from localhost ([::1]:58213 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEWZF-0001tX-5k for importer@patchew.org; Tue, 14 Nov 2017 03:27:37 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39736) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEWOb-000782-CT for qemu-devel@nongnu.org; Tue, 14 Nov 2017 03:16:38 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eEWOa-0005Xy-52 for qemu-devel@nongnu.org; Tue, 14 Nov 2017 03:16:37 -0500 Received: from mail.ispras.ru ([83.149.199.45]:52466) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eEWOZ-0005XO-PR for qemu-devel@nongnu.org; Tue, 14 Nov 2017 03:16:36 -0500 Received: from [127.0.1.1] (unknown [85.142.117.226]) by mail.ispras.ru (Postfix) with ESMTPSA id 04ABE54006A; Tue, 14 Nov 2017 11:16:35 +0300 (MSK) From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Tue, 14 Nov 2017 11:16:43 +0300 Message-ID: <20171114081643.27640.12639.stgit@pasha-VirtualBox> In-Reply-To: <20171114081630.27640.53933.stgit@pasha-VirtualBox> References: <20171114081630.27640.53933.stgit@pasha-VirtualBox> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable 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 v2 02/26] 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, pavel.dovgaluk@ispras.ru, mst@redhat.com, jasowang@redhat.com, quintela@redhat.com, zuban32s@gmail.com, maria.klimushenkova@ispras.ru, dovgaluk@ispras.ru, kraxel@redhat.com, boost.lists@gmail.com, pbonzini@redhat.com, alex.bennee@linaro.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 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 82a88f8..c489d50 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" =20 typedef struct Request { Coroutine *co; QEMUBH *bh; } Request; =20 +static BlockDriverState *blkreplay_append_snapshot(BlockDriverState *bs, + Error **errp) +{ + int ret; + BlockDriverState *bs_snapshot; + int64_t total_size; + QemuOpts *opts =3D NULL; + char tmp_filename[PATH_MAX + 1]; + QDict *snapshot_options =3D 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 =3D 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 =3D bdrv_getlength(bs); + if (total_size < 0) { + error_setg_errno(errp, -total_size, "Could not get image size"); + goto out; + } + + opts =3D qemu_opts_create(bdrv_qcow2.create_opts, NULL, 0, &error_abor= t); + qemu_opt_set_number(opts, BLOCK_OPT_SIZE, total_size, &error_abort); + ret =3D 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 =3D bdrv_open(NULL, NULL, snapshot_options, + BDRV_O_RDWR | BDRV_O_TEMPORARY, errp); + snapshot_options =3D 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 *o= ptions, int flags, goto fail; } =20 + /* Add temporary snapshot to preserve the image */ + if (!replay_snapshot + && !blkreplay_append_snapshot(bs->file->bs, &local_err)) { + ret =3D -EINVAL; + error_propagate(errp, local_err); + goto fail; + } + ret =3D 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" =20 ReplayMode replay_mode; +char *replay_snapshot; =20 int64_t replay_save_clock(unsigned int kind, int64_t clock) { diff --git a/vl.c b/vl.c index ec29909..7aa59f0 100644 --- a/vl.c +++ b/vl.c @@ -4661,7 +4661,7 @@ int main(int argc, char **argv, char **envp) qapi_free_BlockdevOptions(bdo->bdo); g_free(bdo); } - if (snapshot || replay_mode !=3D REPLAY_MODE_NONE) { + if (snapshot) { qemu_opts_foreach(qemu_find_opts("drive"), drive_enable_snapshot, NULL, NULL); }