Commit a2d665c1 authored May 21, 2019 by John Snow Committed by Max Reitz May 28, 2019

blockdev: loosen restrictions on drive-backup source node

We mandate that the source node must be a root node; but there's no reason
I am aware of that it needs to be restricted to such. In some cases, we need
to make sure that there's a medium present, but in the general case we can
allow the backup job itself to do the graph checking.

This patch helps improve the error message when you try to backup from
the same node more than once, which is reflected in the change to test
056.

For backups with bitmaps, it will also show a better error message that
the bitmap is in use instead of giving you something cryptic like "need
a root node."

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1707303


Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 20190521210053.8864-1-jsnow@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

parent 6388903e

blockdev.c

+6 −1

Original line number	Diff line number	Diff line
		@@ -3450,11 +3450,16 @@ static BlockJob do_drive_backup(DriveBackup backup, JobTxn *txn,
		backup->compress = false;
		}

		bs = qmp_get_root_bs(backup->device, errp);
		bs = bdrv_lookup_bs(backup->device, backup->device, errp);
		if (!bs) {
		return NULL;
		}

		if (!bs->drv) {
		error_setg(errp, "Device has no medium");
		return NULL;
		}

		aio_context = bdrv_get_aio_context(bs);
		aio_context_acquire(aio_context);

tests/qemu-iotests/056

+1 −1

Original line number	Diff line number	Diff line
		@@ -214,7 +214,7 @@ class BackupTest(iotests.QMPTestCase):
		res = self.vm.qmp('query-block-jobs')
		self.assert_qmp(res, 'return[0]/status', 'concluded')
		# Leave zombie job un-dismissed, observe a failure:
		res = self.qmp_backup_and_wait(serror='Need a root block node',
		res = self.qmp_backup_and_wait(serror="Node 'drive0' is busy: block device is in use by block job: backup",
		device='drive0', format=iotests.imgfmt,
		sync='full', target=self.dest_img,
		auto_dismiss=False)