block: test block-stream with a base node that is used by block-commit

The base node of a block-stream operation indicates the first image
from the backing chain starting from which no data is copied to the
top node.

The block-stream job allows others to use that base image, so a second
block-stream job could be writing to it at the same time. An important
restriction is that the base image must not disappear while the stream
job is ongoing. stream_start() freezes the backing chain from top to
base with that purpose but it does it too late in the code so there is
a race condition there.

This bug was fixed in the previous commit, and this patch contains an
iotest for this scenario.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Alberto Garcia 2019-03-28 18:25:11 +02:00 committed by Kevin Wolf
parent 20509c4b8b
commit d20ba603f2
2 changed files with 19 additions and 2 deletions

View file

@ -314,6 +314,23 @@ class TestParallelOps(iotests.QMPTestCase):
self.wait_until_completed(drive='commit-drive0')
# In this case the base node of the stream job is the same as the
# top node of commit job. Since block-commit removes the top node
# when it finishes, this is not allowed.
def test_overlapping_4(self):
self.assert_no_active_block_jobs()
# Commit from node2 into node0
result = self.vm.qmp('block-commit', device='drive0', top=self.imgs[2], base=self.imgs[0])
self.assert_qmp(result, 'return', {})
# Stream from node2 into node4
result = self.vm.qmp('block-stream', device='node4', base_node='node2', job_id='node4')
self.assert_qmp(result, 'error/class', 'GenericError')
self.wait_until_completed()
self.assert_no_active_block_jobs()
# Test a block-stream and a block-commit job in parallel
# Here the stream job is supposed to finish quickly in order to reproduce
# the scenario that triggers the bug fixed in 3d5d319e1221 and 1a63a907507

View file

@ -1,5 +1,5 @@
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----------------------------------------------------------------------
Ran 24 tests
Ran 25 tests
OK