diff --git a/block/stream.c b/block/stream.c index 9b0b0f3573..332b9a183e 100644 --- a/block/stream.c +++ b/block/stream.c @@ -90,21 +90,21 @@ static void coroutine_fn stream_run(void *opaque) StreamCompleteData *data; BlockDriverState *bs = s->common.bs; BlockDriverState *base = s->base; - int64_t sector_num, end; + int64_t sector_num = 0; + int64_t end = -1; int error = 0; int ret = 0; int n = 0; void *buf; if (!bs->backing) { - block_job_completed(&s->common, 0); - return; + goto out; } s->common.len = bdrv_getlength(bs); if (s->common.len < 0) { - block_job_completed(&s->common, s->common.len); - return; + ret = s->common.len; + goto out; } end = s->common.len >> BDRV_SECTOR_BITS; @@ -191,6 +191,7 @@ wait: qemu_vfree(buf); +out: /* Modify backing chain and close BDSes in main loop */ data = g_malloc(sizeof(*data)); data->ret = ret; diff --git a/tests/qemu-iotests/030 b/tests/qemu-iotests/030 index 32469efd76..3ac2443e5b 100755 --- a/tests/qemu-iotests/030 +++ b/tests/qemu-iotests/030 @@ -35,6 +35,7 @@ class TestSingleDrive(iotests.QMPTestCase): qemu_img('create', '-f', iotests.imgfmt, '-o', 'backing_file=%s' % backing_img, mid_img) qemu_img('create', '-f', iotests.imgfmt, '-o', 'backing_file=%s' % mid_img, test_img) qemu_io('-f', 'raw', '-c', 'write -P 0x1 0 512', backing_img) + qemu_io('-f', iotests.imgfmt, '-c', 'write -P 0x1 524288 512', mid_img) self.vm = iotests.VM().add_drive("blkdebug::" + test_img) self.vm.launch() @@ -90,10 +91,28 @@ class TestSingleDrive(iotests.QMPTestCase): qemu_io('-f', iotests.imgfmt, '-c', 'map', test_img), 'image file map does not match backing file after streaming') + def test_stream_no_op(self): + self.assert_no_active_block_jobs() + + # The image map is empty before the operation + empty_map = qemu_io('-f', iotests.imgfmt, '-c', 'map', test_img) + + # This is a no-op: no data should ever be copied from the base image + result = self.vm.qmp('block-stream', device='drive0', base=mid_img) + self.assert_qmp(result, 'return', {}) + + self.wait_until_completed() + + self.assert_no_active_block_jobs() + self.vm.shutdown() + + self.assertEqual(qemu_io('-f', iotests.imgfmt, '-c', 'map', test_img), + empty_map, 'image file map changed after a no-op') + def test_stream_partial(self): self.assert_no_active_block_jobs() - result = self.vm.qmp('block-stream', device='drive0', base=mid_img) + result = self.vm.qmp('block-stream', device='drive0', base=backing_img) self.assert_qmp(result, 'return', {}) self.wait_until_completed() diff --git a/tests/qemu-iotests/030.out b/tests/qemu-iotests/030.out index fa16b5ccef..6323079e08 100644 --- a/tests/qemu-iotests/030.out +++ b/tests/qemu-iotests/030.out @@ -1,5 +1,5 @@ -............. +.............. ---------------------------------------------------------------------- -Ran 13 tests +Ran 14 tests OK