From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51295) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZljHO-0006L9-K1 for qemu-devel@nongnu.org; Mon, 12 Oct 2015 16:01:09 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZljHN-0000F6-Ax for qemu-devel@nongnu.org; Mon, 12 Oct 2015 16:01:06 -0400 From: Max Reitz Date: Mon, 12 Oct 2015 22:00:06 +0200 Message-Id: <1444680042-13207-4-git-send-email-mreitz@redhat.com> In-Reply-To: <1444680042-13207-1-git-send-email-mreitz@redhat.com> References: <1444680042-13207-1-git-send-email-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH v6 03/39] blockdev: Allow creation of BDS trees without BB List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: Kevin Wolf , Alberto Garcia , Markus Armbruster , qemu-devel@nongnu.org, Max Reitz , John Snow , Stefan Hajnoczi If the "id" field is missing from the options given to blockdev-add, just omit the BlockBackend and create the BlockDriverState tree alone. However, if "id" is missing, "node-name" must be specified; otherwise, the BDS tree would no longer be accessible. Many BDS options which are not parsed by bdrv_open() (like caching) cannot be specified for these BB-less BDS trees yet. A future patch will remove this limitation. Signed-off-by: Max Reitz Reviewed-by: Eric Blake Reviewed-by: Kevin Wolf Reviewed-by: Alberto Garcia --- blockdev.c | 44 +++++++++++++++++++++++++++++++------------- qapi/block-core.json | 13 +++++++++---- tests/qemu-iotests/087 | 2 +- tests/qemu-iotests/087.out | 4 ++-- 4 files changed, 43 insertions(+), 20 deletions(-) diff --git a/blockdev.c b/blockdev.c index f937526..07b9a3d 100644 --- a/blockdev.c +++ b/blockdev.c @@ -3028,17 +3028,12 @@ out: void qmp_blockdev_add(BlockdevOptions *options, Error **errp) { QmpOutputVisitor *ov = qmp_output_visitor_new(); - BlockBackend *blk; + BlockDriverState *bs; + BlockBackend *blk = NULL; QObject *obj; QDict *qdict; Error *local_err = NULL; - /* Require an ID in the top level */ - if (!options->has_id) { - error_setg(errp, "Block device needs an ID"); - goto fail; - } - /* TODO Sort it out in raw-posix and drive_new(): Reject aio=native with * cache.direct=false instead of silently switching to aio=threads, except * when called from drive_new(). @@ -3066,14 +3061,37 @@ void qmp_blockdev_add(BlockdevOptions *options, Error **errp) qdict_flatten(qdict); - blk = blockdev_init(NULL, qdict, &local_err); - if (local_err) { - error_propagate(errp, local_err); - goto fail; + if (options->has_id) { + blk = blockdev_init(NULL, qdict, &local_err); + if (local_err) { + error_propagate(errp, local_err); + goto fail; + } + + bs = blk_bs(blk); + } else { + int ret; + + if (!qdict_get_try_str(qdict, "node-name")) { + error_setg(errp, "'id' and/or 'node-name' need to be specified for " + "the root node"); + goto fail; + } + + bs = NULL; + ret = bdrv_open(&bs, NULL, NULL, qdict, BDRV_O_RDWR | BDRV_O_CACHE_WB, + errp); + if (ret < 0) { + goto fail; + } } - if (bdrv_key_required(blk_bs(blk))) { - blk_unref(blk); + if (bs && bdrv_key_required(bs)) { + if (blk) { + blk_unref(blk); + } else { + bdrv_unref(bs); + } error_setg(errp, "blockdev-add doesn't support encrypted devices"); goto fail; } diff --git a/qapi/block-core.json b/qapi/block-core.json index c042561..425fdab 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -1393,9 +1393,12 @@ # # @driver: block driver name # @id: #optional id by which the new block device can be referred to. -# This is a required option on the top level of blockdev-add, and -# currently not allowed on any other level. -# @node-name: #optional the name of a block driver state node (Since 2.0) +# This option is only allowed on the top level of blockdev-add. +# A BlockBackend will be created by blockdev-add if and only if +# this option is given. +# @node-name: #optional the name of a block driver state node (Since 2.0). +# This option is required on the top level of blockdev-add if +# the @id option is not given there. # @discard: #optional discard-related options (default: ignore) # @cache: #optional cache-related options # @aio: #optional AIO backend (default: threads) @@ -1859,7 +1862,9 @@ ## # @blockdev-add: # -# Creates a new block device. +# Creates a new block device. If the @id option is given at the top level, a +# BlockBackend will be created; otherwise, @node-name is mandatory at the top +# level and no BlockBackend will be created. # # This command is still a work in progress. It doesn't support all # block drivers, it lacks a matching blockdev-del, and more. Stay diff --git a/tests/qemu-iotests/087 b/tests/qemu-iotests/087 index 8694749..af44299 100755 --- a/tests/qemu-iotests/087 +++ b/tests/qemu-iotests/087 @@ -54,7 +54,7 @@ size=128M _make_test_img $size echo -echo === Missing ID === +echo === Missing ID and node-name === echo run_qemu <