From 20a63d2cec838c2dde4d246c4d7abe747d9b7a11 Mon Sep 17 00:00:00 2001 From: Fam Zheng Date: Mon, 16 Dec 2013 14:45:31 +0800 Subject: commit: Support commit active layer If active is top, it will be mirrored to base, (with block/mirror.c code), then the image is switched when user completes the block job. QMP documentation is updated. Signed-off-by: Fam Zheng Signed-off-by: Stefan Hajnoczi --- block/mirror.c | 11 +++++++++++ blockdev.c | 9 +++++++-- qapi-schema.json | 5 +++-- 3 files changed, 21 insertions(+), 4 deletions(-) diff --git a/block/mirror.c b/block/mirror.c index 04af341be6..2932bab27a 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -481,6 +481,13 @@ immediate_exit: bdrv_reopen(s->target, bdrv_get_flags(s->common.bs), NULL); } bdrv_swap(s->target, s->common.bs); + if (s->common.driver->job_type == BLOCK_JOB_TYPE_COMMIT) { + /* drop the bs loop chain formed by the swap: break the loop then + * trigger the unref from the top one */ + BlockDriverState *p = s->base->backing_hd; + s->base->backing_hd = NULL; + bdrv_unref(p); + } } bdrv_unref(s->target); block_job_completed(&s->common, ret); @@ -623,6 +630,10 @@ void commit_active_start(BlockDriverState *bs, BlockDriverState *base, BlockDriverCompletionFunc *cb, void *opaque, Error **errp) { + if (bdrv_reopen(base, bs->open_flags, errp)) { + return; + } + bdrv_ref(base); mirror_start_job(bs, base, speed, 0, 0, on_error, on_error, cb, opaque, errp, &commit_active_job_driver, false, base); diff --git a/blockdev.c b/blockdev.c index 6a85961af2..2c3242b87a 100644 --- a/blockdev.c +++ b/blockdev.c @@ -1820,8 +1820,13 @@ void qmp_block_commit(const char *device, return; } - commit_start(bs, base_bs, top_bs, speed, on_error, block_job_cb, bs, - &local_err); + if (top_bs == bs) { + commit_active_start(bs, base_bs, speed, on_error, block_job_cb, + bs, &local_err); + } else { + commit_start(bs, base_bs, top_bs, speed, on_error, block_job_cb, bs, + &local_err); + } if (local_err != NULL) { error_propagate(errp, local_err); return; diff --git a/qapi-schema.json b/qapi-schema.json index 5aa4581792..b9b051c1fa 100644 --- a/qapi-schema.json +++ b/qapi-schema.json @@ -1967,9 +1967,11 @@ # # @top: The file name of the backing image within the image chain, # which contains the topmost data to be committed down. -# Note, the active layer as 'top' is currently unsupported. # # If top == base, that is an error. +# If top == active, the job will not be completed by itself, +# user needs to complete the job with the block-job-complete +# command after getting the ready event. (Since 2.0) # # # @speed: #optional the maximum speed, in bytes per second @@ -1979,7 +1981,6 @@ # If @device does not exist, DeviceNotFound # If image commit is not supported by this device, NotSupported # If @base or @top is invalid, a generic error is returned -# If @top is the active layer, or omitted, a generic error is returned # If @speed is invalid, InvalidParameter # # Since: 1.3 -- cgit v1.2.1