Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block layer patches:

- qemu-img create: Fail gracefully when backing file is an empty string
- Fixes related to filter block nodes ("Deal with filters" series)
- block/nvme: Various cleanups required to use multiple queues
- block/nvme: Use NvmeBar structure from "block/nvme.h"
- file-win32: Fix "locking" option
- iotests: Allow running from different directory

# gpg: Signature made Thu 10 Sep 2020 10:11:19 BST
# gpg:                using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg:                issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream: (65 commits)
  block/qcow2-cluster: Add missing "fallthrough" annotation
  block/nvme: Pair doorbell registers
  block/nvme: Use generic NvmeBar structure
  block/nvme: Group controller registers in NVMeRegs structure
  file-win32: Fix "locking" option
  iotests: Allow running from different directory
  iotests: Test committing to overridden backing
  iotests: Add test for commit in sub directory
  iotests: Add filter mirror test cases
  iotests: Add filter commit test cases
  iotests: Let complete_and_wait() work with commit
  iotests: Test that qcow2's data-file is flushed
  block: Leave BDS.backing_{file,format} constant
  block: Inline bdrv_co_block_status_from_*()
  blockdev: Fix active commit choice
  block: Drop backing_bs()
  qemu-img: Use child access functions
  nbd: Use CAF when looking for dirty bitmap
  commit: Deal with filters
  backup: Deal with filters
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

20 files changed, 539 insertions, 24 deletions

diff --git a/tests/qemu-iotests/020 b/tests/qemu-iotests/020
index a078293..596505b 100755
--- a/tests/qemu-iotests/020
+++ b/tests/qemu-iotests/020
@@ -31,6 +31,11 @@ _cleanup()
     _cleanup_test_img
     _rm_test_img "$TEST_IMG.base"
     _rm_test_img "$TEST_IMG.orig"
+
+    _rm_test_img "$TEST_DIR/subdir/t.$IMGFMT.base"
+    _rm_test_img "$TEST_DIR/subdir/t.$IMGFMT.mid"
+    _rm_test_img "$TEST_DIR/subdir/t.$IMGFMT"
+    rmdir "$TEST_DIR/subdir" &> /dev/null
 }
 trap "_cleanup; exit \$status" 0 1 2 3 15
 
@@ -139,6 +144,45 @@ $QEMU_IO -c 'writev 0 64k' "$TEST_IMG" | _filter_qemu_io
 $QEMU_IMG commit "$TEST_IMG"
 _cleanup
 
+
+echo
+echo 'Testing commit in sub-directory with relative filenames'
+echo
+
+pushd "$TEST_DIR" > /dev/null
+
+mkdir subdir
+
+TEST_IMG="subdir/t.$IMGFMT.base" _make_test_img 1M
+TEST_IMG="subdir/t.$IMGFMT.mid" _make_test_img -b "t.$IMGFMT.base" -F $IMGFMT
+TEST_IMG="subdir/t.$IMGFMT" _make_test_img -b "t.$IMGFMT.mid" -F $IMGFMT
+
+# Should work
+$QEMU_IMG commit -b "t.$IMGFMT.mid" "subdir/t.$IMGFMT"
+
+# Might theoretically work, but does not in practice (we have to
+# decide between this and the above; and since we always represent
+# backing file names as relative to the overlay, we go for the above)
+$QEMU_IMG commit -b "subdir/t.$IMGFMT.mid" "subdir/t.$IMGFMT" 2>&1 | \
+    _filter_imgfmt
+
+# This should work as well
+$QEMU_IMG commit -b "$TEST_DIR/subdir/t.$IMGFMT.mid" "subdir/t.$IMGFMT"
+
+popd > /dev/null
+
+# Now let's try with just absolute filenames
+# (This will not work with external data files, though, because when
+# using relative paths for those, qemu will always resolve them
+# relative to its CWD.  Therefore, it cannot find those data files now
+# that we left $TEST_DIR.)
+if _get_data_file '' > /dev/null; then
+    echo 'Image committed.' # Skip test
+else
+    $QEMU_IMG commit -b "$TEST_DIR/subdir/t.$IMGFMT.mid" \
+        "$TEST_DIR/subdir/t.$IMGFMT"
+fi
+
 # success, all done
 echo "*** done"
 rm -f $seq.full
diff --git a/tests/qemu-iotests/020.out b/tests/qemu-iotests/020.out
index 5936bc1..a5db196 100644
--- a/tests/qemu-iotests/020.out
+++ b/tests/qemu-iotests/020.out
@@ -1083,4 +1083,14 @@ Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 backing_file=json:{'driv
 wrote 65536/65536 bytes at offset 0
 64 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
 qemu-img: Block job failed: No space left on device
+
+Testing commit in sub-directory with relative filenames
+
+Formatting 'subdir/t.IMGFMT.base', fmt=IMGFMT size=1048576
+Formatting 'subdir/t.IMGFMT.mid', fmt=IMGFMT size=1048576 backing_file=t.IMGFMT.base backing_fmt=IMGFMT
+Formatting 'subdir/t.IMGFMT', fmt=IMGFMT size=1048576 backing_file=t.IMGFMT.mid backing_fmt=IMGFMT
+Image committed.
+qemu-img: Did not find 'subdir/t.IMGFMT.mid' in the backing chain of 'subdir/t.IMGFMT'
+Image committed.
+Image committed.
 *** done
diff --git a/tests/qemu-iotests/040 b/tests/qemu-iotests/040
index f58f50d..caf2865 100755
--- a/tests/qemu-iotests/040
+++ b/tests/qemu-iotests/040
@@ -734,6 +734,244 @@ class TestErrorHandling(iotests.QMPTestCase):
         self.assertTrue(iotests.compare_images(mid_img, backing_img, fmt2='raw'),
                         'target image does not match source after commit')
 
+class TestCommitWithFilters(iotests.QMPTestCase):
+    img0 = os.path.join(iotests.test_dir, '0.img')
+    img1 = os.path.join(iotests.test_dir, '1.img')
+    img2 = os.path.join(iotests.test_dir, '2.img')
+    img3 = os.path.join(iotests.test_dir, '3.img')
+
+    def do_test_io(self, read_or_write):
+        for index, pattern_file in enumerate(self.pattern_files):
+            result = qemu_io('-f', iotests.imgfmt,
+                             '-c',
+                             f'{read_or_write} -P {index + 1} {index}M 1M',
+                             pattern_file)
+            self.assertFalse('Pattern verification failed' in result)
+
+    def setUp(self):
+        qemu_img('create', '-f', iotests.imgfmt, self.img0, '64M')
+        qemu_img('create', '-f', iotests.imgfmt, self.img1, '64M')
+        qemu_img('create', '-f', iotests.imgfmt, self.img2, '64M')
+        qemu_img('create', '-f', iotests.imgfmt, self.img3, '64M')
+
+        # Distributions of the patterns in the files; this is checked
+        # by tearDown() and should be changed by the test cases as is
+        # necessary
+        self.pattern_files = [self.img0, self.img1, self.img2, self.img3]
+
+        self.do_test_io('write')
+
+        self.vm = iotests.VM().add_device('virtio-scsi,id=vio-scsi')
+        self.vm.launch()
+
+        result = self.vm.qmp('object-add', qom_type='throttle-group', id='tg')
+        self.assert_qmp(result, 'return', {})
+
+        result = self.vm.qmp('blockdev-add', **{
+                'node-name': 'top-filter',
+                'driver': 'throttle',
+                'throttle-group': 'tg',
+                'file': {
+                    'node-name': 'cow-3',
+                    'driver': iotests.imgfmt,
+                    'file': {
+                        'driver': 'file',
+                        'filename': self.img3
+                    },
+                    'backing': {
+                        'node-name': 'cow-2',
+                        'driver': iotests.imgfmt,
+                        'file': {
+                            'driver': 'file',
+                            'filename': self.img2
+                        },
+                        'backing': {
+                            'node-name': 'cow-1',
+                            'driver': iotests.imgfmt,
+                            'file': {
+                                'driver': 'file',
+                                'filename': self.img1
+                            },
+                            'backing': {
+                                'node-name': 'bottom-filter',
+                                'driver': 'throttle',
+                                'throttle-group': 'tg',
+                                'file': {
+                                    'node-name': 'cow-0',
+                                    'driver': iotests.imgfmt,
+                                    'file': {
+                                        'driver': 'file',
+                                        'filename': self.img0
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+            })
+        self.assert_qmp(result, 'return', {})
+
+    def tearDown(self):
+        self.vm.shutdown()
+        self.do_test_io('read')
+
+        os.remove(self.img3)
+        os.remove(self.img2)
+        os.remove(self.img1)
+        os.remove(self.img0)
+
+    # Filters make for funny filenames, so we cannot just use
+    # self.imgX to get them
+    def get_filename(self, node):
+        return self.vm.node_info(node)['image']['filename']
+
+    def test_filterless_commit(self):
+        result = self.vm.qmp('block-commit',
+                             job_id='commit',
+                             device='top-filter',
+                             top_node='cow-2',
+                             base_node='cow-1')
+        self.assert_qmp(result, 'return', {})
+        self.wait_until_completed(drive='commit')
+
+        self.assertIsNotNone(self.vm.node_info('cow-3'))
+        self.assertIsNone(self.vm.node_info('cow-2'))
+        self.assertIsNotNone(self.vm.node_info('cow-1'))
+
+        # 2 has been comitted into 1
+        self.pattern_files[2] = self.img1
+
+    def test_commit_through_filter(self):
+        result = self.vm.qmp('block-commit',
+                             job_id='commit',
+                             device='top-filter',
+                             top_node='cow-1',
+                             base_node='cow-0')
+        self.assert_qmp(result, 'return', {})
+        self.wait_until_completed(drive='commit')
+
+        self.assertIsNotNone(self.vm.node_info('cow-2'))
+        self.assertIsNone(self.vm.node_info('cow-1'))
+        self.assertIsNone(self.vm.node_info('bottom-filter'))
+        self.assertIsNotNone(self.vm.node_info('cow-0'))
+
+        # 1 has been comitted into 0
+        self.pattern_files[1] = self.img0
+
+    def test_filtered_active_commit_with_filter(self):
+        # Add a device, so the commit job finds a parent it can change
+        # to point to the base node (so we can test that top-filter is
+        # dropped from the graph)
+        result = self.vm.qmp('device_add', id='drv0', driver='scsi-hd',
+                             bus='vio-scsi.0', drive='top-filter')
+        self.assert_qmp(result, 'return', {})
+
+        # Try to release our reference to top-filter; that should not
+        # work because drv0 uses it
+        result = self.vm.qmp('blockdev-del', node_name='top-filter')
+        self.assert_qmp(result, 'error/class', 'GenericError')
+        self.assert_qmp(result, 'error/desc', 'Node top-filter is in use')
+
+        result = self.vm.qmp('block-commit',
+                             job_id='commit',
+                             device='top-filter',
+                             base_node='cow-2')
+        self.assert_qmp(result, 'return', {})
+        self.complete_and_wait(drive='commit')
+
+        # Try to release our reference to top-filter again
+        result = self.vm.qmp('blockdev-del', node_name='top-filter')
+        self.assert_qmp(result, 'return', {})
+
+        self.assertIsNone(self.vm.node_info('top-filter'))
+        self.assertIsNone(self.vm.node_info('cow-3'))
+        self.assertIsNotNone(self.vm.node_info('cow-2'))
+
+        # Check that drv0 is now connected to cow-2
+        blockdevs = self.vm.qmp('query-block')['return']
+        drv0 = next(dev for dev in blockdevs if dev['qdev'] == 'drv0')
+        self.assertEqual(drv0['inserted']['node-name'], 'cow-2')
+
+        # 3 has been comitted into 2
+        self.pattern_files[3] = self.img2
+
+    def test_filtered_active_commit_without_filter(self):
+        result = self.vm.qmp('block-commit',
+                             job_id='commit',
+                             device='top-filter',
+                             top_node='cow-3',
+                             base_node='cow-2')
+        self.assert_qmp(result, 'return', {})
+        self.complete_and_wait(drive='commit')
+
+        self.assertIsNotNone(self.vm.node_info('top-filter'))
+        self.assertIsNone(self.vm.node_info('cow-3'))
+        self.assertIsNotNone(self.vm.node_info('cow-2'))
+
+        # 3 has been comitted into 2
+        self.pattern_files[3] = self.img2
+
+class TestCommitWithOverriddenBacking(iotests.QMPTestCase):
+    img_base_a = os.path.join(iotests.test_dir, 'base_a.img')
+    img_base_b = os.path.join(iotests.test_dir, 'base_b.img')
+    img_top = os.path.join(iotests.test_dir, 'top.img')
+
+    def setUp(self):
+        qemu_img('create', '-f', iotests.imgfmt, self.img_base_a, '1M')
+        qemu_img('create', '-f', iotests.imgfmt, self.img_base_b, '1M')
+        qemu_img('create', '-f', iotests.imgfmt, '-b', self.img_base_a, \
+                 self.img_top)
+
+        self.vm = iotests.VM()
+        self.vm.launch()
+
+        # Use base_b instead of base_a as the backing of top
+        result = self.vm.qmp('blockdev-add', **{
+                                'node-name': 'top',
+                                'driver': iotests.imgfmt,
+                                'file': {
+                                    'driver': 'file',
+                                    'filename': self.img_top
+                                },
+                                'backing': {
+                                    'node-name': 'base',
+                                    'driver': iotests.imgfmt,
+                                    'file': {
+                                        'driver': 'file',
+                                        'filename': self.img_base_b
+                                    }
+                                }
+                            })
+        self.assert_qmp(result, 'return', {})
+
+    def tearDown(self):
+        self.vm.shutdown()
+        os.remove(self.img_top)
+        os.remove(self.img_base_a)
+        os.remove(self.img_base_b)
+
+    def test_commit_to_a(self):
+        # Try committing to base_a (which should fail, as top's
+        # backing image is base_b instead)
+        result = self.vm.qmp('block-commit',
+                             job_id='commit',
+                             device='top',
+                             base=self.img_base_a)
+        self.assert_qmp(result, 'error/class', 'GenericError')
+
+    def test_commit_to_b(self):
+        # Try committing to base_b (which should work, since that is
+        # actually top's backing image)
+        result = self.vm.qmp('block-commit',
+                             job_id='commit',
+                             device='top',
+                             base=self.img_base_b)
+        self.assert_qmp(result, 'return', {})
+
+        self.vm.event_wait('BLOCK_JOB_READY')
+        self.vm.qmp('block-job-complete', device='commit')
+        self.vm.event_wait('BLOCK_JOB_COMPLETED')
+
 if __name__ == '__main__':
     iotests.main(supported_fmts=['qcow2', 'qed'],
                  supported_protocols=['file'])
diff --git a/tests/qemu-iotests/040.out b/tests/qemu-iotests/040.out
index 6a91713..1bb1dc5 100644
--- a/tests/qemu-iotests/040.out
+++ b/tests/qemu-iotests/040.out
@@ -1,5 +1,5 @@
-...........................................................
+.................................................................
 ----------------------------------------------------------------------
-Ran 59 tests
+Ran 65 tests
 
 OK
diff --git a/tests/qemu-iotests/041 b/tests/qemu-iotests/041
index f0a7bf6..a778085 100755
--- a/tests/qemu-iotests/041
+++ b/tests/qemu-iotests/041
@@ -21,8 +21,9 @@
 import time
 import os
 import re
+import json
 import iotests
-from iotests import qemu_img, qemu_io
+from iotests import qemu_img, qemu_img_pipe, qemu_io
 
 backing_img = os.path.join(iotests.test_dir, 'backing.img')
 target_backing_img = os.path.join(iotests.test_dir, 'target-backing.img')
@@ -1288,6 +1289,149 @@ class TestReplaces(iotests.QMPTestCase):
 
         self.vm.assert_block_path('filter0', '/file', 'target')
 
+# Tests for mirror with filters (and how the mirror filter behaves, as
+# an example for an implicit filter)
+class TestFilters(iotests.QMPTestCase):
+    def setUp(self):
+        qemu_img('create', '-f', iotests.imgfmt, backing_img, '1M')
+        qemu_img('create', '-f', iotests.imgfmt, '-b', backing_img, test_img)
+        qemu_img('create', '-f', iotests.imgfmt, '-b', backing_img, target_img)
+
+        qemu_io('-c', 'write -P 1 0 512k', backing_img)
+        qemu_io('-c', 'write -P 2 512k 512k', test_img)
+
+        self.vm = iotests.VM().add_device('virtio-scsi,id=vio-scsi')
+        self.vm.launch()
+
+        result = self.vm.qmp('blockdev-add', **{
+                                'node-name': 'target',
+                                'driver': iotests.imgfmt,
+                                'file': {
+                                    'driver': 'file',
+                                    'filename': target_img
+                                },
+                                'backing': None
+                            })
+        self.assert_qmp(result, 'return', {})
+
+        self.filterless_chain = {
+                'node-name': 'source',
+                'driver': iotests.imgfmt,
+                'file': {
+                    'driver': 'file',
+                    'filename': test_img
+                },
+                'backing': {
+                    'node-name': 'backing',
+                    'driver': iotests.imgfmt,
+                    'file': {
+                        'driver': 'file',
+                        'filename': backing_img
+                    }
+                }
+            }
+
+    def tearDown(self):
+        self.vm.shutdown()
+
+        os.remove(test_img)
+        os.remove(target_img)
+        os.remove(backing_img)
+
+    def test_cor(self):
+        result = self.vm.qmp('blockdev-add', **{
+                                'node-name': 'filter',
+                                'driver': 'copy-on-read',
+                                'file': self.filterless_chain
+                            })
+        self.assert_qmp(result, 'return', {})
+
+        result = self.vm.qmp('blockdev-mirror',
+                             job_id='mirror',
+                             device='filter',
+                             target='target',
+                             sync='top')
+        self.assert_qmp(result, 'return', {})
+
+        self.complete_and_wait('mirror')
+
+        self.vm.qmp('blockdev-del', node_name='target')
+
+        target_map = qemu_img_pipe('map', '--output=json', target_img)
+        target_map = json.loads(target_map)
+
+        assert target_map[0]['start'] == 0
+        assert target_map[0]['length'] == 512 * 1024
+        assert target_map[0]['depth'] == 1
+
+        assert target_map[1]['start'] == 512 * 1024
+        assert target_map[1]['length'] == 512 * 1024
+        assert target_map[1]['depth'] == 0
+
+    def test_implicit_mirror_filter(self):
+        result = self.vm.qmp('blockdev-add', **self.filterless_chain)
+        self.assert_qmp(result, 'return', {})
+
+        # We need this so we can query from above the mirror node
+        result = self.vm.qmp('device_add',
+                             driver='scsi-hd',
+                             id='virtio',
+                             bus='vio-scsi.0',
+                             drive='source')
+        self.assert_qmp(result, 'return', {})
+
+        result = self.vm.qmp('blockdev-mirror',
+                             job_id='mirror',
+                             device='source',
+                             target='target',
+                             sync='top')
+        self.assert_qmp(result, 'return', {})
+
+        # The mirror filter is now an implicit node, so it should be
+        # invisible when querying the backing chain
+        blockdevs = self.vm.qmp('query-block')['return']
+        device_info = next(dev for dev in blockdevs if dev['qdev'] == 'virtio')
+
+        assert device_info['inserted']['node-name'] == 'source'
+
+        image_info = device_info['inserted']['image']
+        assert image_info['filename'] == test_img
+        assert image_info['backing-image']['filename'] == backing_img
+
+        self.complete_and_wait('mirror')
+
+    def test_explicit_mirror_filter(self):
+        # Same test as above, but this time we give the mirror filter
+        # a node-name so it will not be invisible
+        result = self.vm.qmp('blockdev-add', **self.filterless_chain)
+        self.assert_qmp(result, 'return', {})
+
+        # We need this so we can query from above the mirror node
+        result = self.vm.qmp('device_add',
+                             driver='scsi-hd',
+                             id='virtio',
+                             bus='vio-scsi.0',
+                             drive='source')
+        self.assert_qmp(result, 'return', {})
+
+        result = self.vm.qmp('blockdev-mirror',
+                             job_id='mirror',
+                             device='source',
+                             target='target',
+                             sync='top',
+                             filter_node_name='mirror-filter')
+        self.assert_qmp(result, 'return', {})
+
+        # With a node-name given to it, the mirror filter should now
+        # be visible
+        blockdevs = self.vm.qmp('query-block')['return']
+        device_info = next(dev for dev in blockdevs if dev['qdev'] == 'virtio')
+
+        assert device_info['inserted']['node-name'] == 'mirror-filter'
+
+        self.complete_and_wait('mirror')
+
+
 if __name__ == '__main__':
     iotests.main(supported_fmts=['qcow2', 'qed'],
                  supported_protocols=['file'],
diff --git a/tests/qemu-iotests/041.out b/tests/qemu-iotests/041.out
index 53abe11..4665195 100644
--- a/tests/qemu-iotests/041.out
+++ b/tests/qemu-iotests/041.out
@@ -1,5 +1,5 @@
-........................................................................................................
+...........................................................................................................
 ----------------------------------------------------------------------
-Ran 104 tests
+Ran 107 tests
 
 OK
diff --git a/tests/qemu-iotests/049 b/tests/qemu-iotests/049
index 051a1c7..82b1e6c 100755
--- a/tests/qemu-iotests/049
+++ b/tests/qemu-iotests/049
@@ -119,6 +119,10 @@ test_qemu_img create -f $IMGFMT -o compat=1.1,lazy_refcounts=on "$TEST_IMG" 64M
 test_qemu_img create -f $IMGFMT -o compat=0.10,lazy_refcounts=off "$TEST_IMG" 64M
 test_qemu_img create -f $IMGFMT -o compat=0.10,lazy_refcounts=on "$TEST_IMG" 64M
 
+echo "== Expect error when backing file name is empty string =="
+echo
+test_qemu_img create -f $IMGFMT -b '' $TEST_IMG 1M
+
 # success, all done
 echo "*** done"
 rm -f $seq.full
diff --git a/tests/qemu-iotests/049.out b/tests/qemu-iotests/049.out
index a7e2208..b1d8fd9 100644
--- a/tests/qemu-iotests/049.out
+++ b/tests/qemu-iotests/049.out
@@ -209,4 +209,9 @@ qemu-img create -f qcow2 -o compat=0.10,lazy_refcounts=on TEST_DIR/t.qcow2 64M
 Formatting 'TEST_DIR/t.qcow2', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=67108864 compat=0.10 lazy_refcounts=on refcount_bits=16
 qemu-img: TEST_DIR/t.qcow2: Lazy refcounts only supported with compatibility level 1.1 and above (use version=v3 or greater)
 
+== Expect error when backing file name is empty string ==
+
+qemu-img create -f qcow2 -b  TEST_DIR/t.qcow2 1M
+qemu-img: TEST_DIR/t.qcow2: Expected backing file name, got empty string
+
 *** done
diff --git a/tests/qemu-iotests/153.out b/tests/qemu-iotests/153.out
index 8a79e1e..fcaa71a 100644
--- a/tests/qemu-iotests/153.out
+++ b/tests/qemu-iotests/153.out
@@ -464,7 +464,7 @@ No conflict:
 image: null-co://
 file format: null-co
 virtual size: 1 GiB (1073741824 bytes)
-disk size: unavailable
+disk size: 0 B
 
 Conflict:
 qemu-img: --force-share/-U conflicts with image options
diff --git a/tests/qemu-iotests/184 b/tests/qemu-iotests/184
index 33dd8d2..eebb53f 100755
--- a/tests/qemu-iotests/184
+++ b/tests/qemu-iotests/184
@@ -45,8 +45,7 @@ do_run_qemu()
 run_qemu()
 {
     do_run_qemu "$@" 2>&1 | _filter_testdir | _filter_qemu | _filter_qmp\
-                          | _filter_qemu_io | _filter_generated_node_ids \
-                          | _filter_actual_image_size
+                          | _filter_qemu_io | _filter_generated_node_ids
 }
 
 test_throttle=$($QEMU_IMG --help|grep throttle)
diff --git a/tests/qemu-iotests/184.out b/tests/qemu-iotests/184.out
index 3deb3cf..87c7307 100644
--- a/tests/qemu-iotests/184.out
+++ b/tests/qemu-iotests/184.out
@@ -27,14 +27,21 @@ Testing:
             "iops_rd": 0,
             "detect_zeroes": "off",
             "image": {
+                "backing-image": {
+                    "virtual-size": 1073741824,
+                    "filename": "null-co://",
+                    "format": "null-co",
+                    "actual-size": 0
+                },
                 "virtual-size": 1073741824,
                 "filename": "json:{\"throttle-group\": \"group0\", \"driver\": \"throttle\", \"file\": {\"driver\": \"null-co\"}}",
-                "format": "throttle"
+                "format": "throttle",
+                "actual-size": 0
             },
             "iops_wr": 0,
             "ro": false,
             "node-name": "throttle0",
-            "backing_file_depth": 0,
+            "backing_file_depth": 1,
             "drv": "throttle",
             "iops": 0,
             "bps_wr": 0,
@@ -56,7 +63,8 @@ Testing:
             "image": {
                 "virtual-size": 1073741824,
                 "filename": "null-co://",
-                "format": "null-co"
+                "format": "null-co",
+                "actual-size": 0
             },
             "iops_wr": 0,
             "ro": false,
diff --git a/tests/qemu-iotests/204.out b/tests/qemu-iotests/204.out
index 457f72d..4d903d2 100644
--- a/tests/qemu-iotests/204.out
+++ b/tests/qemu-iotests/204.out
@@ -59,5 +59,6 @@ Offset          Length          File
 0x900000        0x2400000       TEST_DIR/t.IMGFMT
 0x3c00000       0x1100000       TEST_DIR/t.IMGFMT
 0x6a00000       0x400000        TEST_DIR/t.IMGFMT
+0x6e00000       0x1200000       TEST_DIR/t.IMGFMT.base
 No errors were found on the image.
 *** done
diff --git a/tests/qemu-iotests/228 b/tests/qemu-iotests/228
index 60db986..266fce6 100755
--- a/tests/qemu-iotests/228
+++ b/tests/qemu-iotests/228
@@ -36,7 +36,7 @@ def log_node_info(node):
 
     log('bs->filename: ' + node['image']['filename'],
         filters=[filter_testfiles, filter_imgfmt])
-    log('bs->backing_file: ' + node['backing_file'],
+    log('bs->backing_file: ' + node['image']['full-backing-filename'],
         filters=[filter_testfiles, filter_imgfmt])
 
     if 'backing-image' in node['image']:
@@ -73,8 +73,8 @@ with iotests.FilePath('base.img') as base_img_path, \
                 },
                 filters=[filter_qmp_testfiles, filter_qmp_imgfmt])
 
-    # Filename should be plain, and the backing filename should not
-    # contain the "file:" prefix
+    # Filename should be plain, and the backing node filename should
+    # not contain the "file:" prefix
     log_node_info(vm.node_info('node0'))
 
     vm.qmp_log('blockdev-del', node_name='node0')
diff --git a/tests/qemu-iotests/228.out b/tests/qemu-iotests/228.out
index 4217df2..8c82009 100644
--- a/tests/qemu-iotests/228.out
+++ b/tests/qemu-iotests/228.out
@@ -4,7 +4,7 @@
 {"return": {}}
 
 bs->filename: TEST_DIR/PID-top.img
-bs->backing_file: TEST_DIR/PID-base.img
+bs->backing_file: file:TEST_DIR/PID-base.img
 bs->backing->bs->filename: TEST_DIR/PID-base.img
 
 {"execute": "blockdev-del", "arguments": {"node-name": "node0"}}
@@ -41,7 +41,7 @@ bs->backing->bs->filename: TEST_DIR/PID-base.img
 {"return": {}}
 
 bs->filename: TEST_DIR/PID-top.img
-bs->backing_file: TEST_DIR/PID-base.img
+bs->backing_file: file:TEST_DIR/PID-base.img
 bs->backing->bs->filename: TEST_DIR/PID-base.img
 
 {"execute": "blockdev-del", "arguments": {"node-name": "node0"}}
@@ -55,7 +55,7 @@ bs->backing->bs->filename: TEST_DIR/PID-base.img
 {"return": {}}
 
 bs->filename: json:{"backing": {"driver": "null-co"}, "driver": "IMGFMT", "file": {"driver": "file", "filename": "TEST_DIR/PID-top.img"}}
-bs->backing_file: null-co://
+bs->backing_file: TEST_DIR/PID-base.img
 bs->backing->bs->filename: null-co://
 
 {"execute": "blockdev-del", "arguments": {"node-name": "node0"}}
diff --git a/tests/qemu-iotests/244 b/tests/qemu-iotests/244
index efe3c04..f2b2ddd 100755
--- a/tests/qemu-iotests/244
+++ b/tests/qemu-iotests/244
@@ -217,6 +217,55 @@ $QEMU_IMG amend -f $IMGFMT -o "data_file=blkdebug::$TEST_IMG.data" "$TEST_IMG"
 $QEMU_IMG convert -f $IMGFMT -O $IMGFMT -n -C "$TEST_IMG.src" "$TEST_IMG"
 $QEMU_IMG compare -f $IMGFMT -F $IMGFMT "$TEST_IMG.src" "$TEST_IMG"
 
+echo
+echo "=== Flushing should flush the data file ==="
+echo
+
+# We are going to flush a qcow2 file with a blkdebug node inserted
+# between the qcow2 node and its data file node.  The blkdebug node
+# will return an error for all flushes and so we if the data file is
+# flushed, we will see qemu-io return an error.
+
+# We need to write something or the flush will not do anything; we
+# also need -t writeback so the write is not done as a FUA write
+# (which would then fail thanks to the implicit flush)
+$QEMU_IO -c 'write 0 512' -c flush \
+    -t writeback \
+    "json:{
+         'driver': 'qcow2',
+         'file': {
+             'driver': 'file',
+             'filename': '$TEST_IMG'
+         },
+         'data-file': {
+             'driver': 'blkdebug',
+             'inject-error': [{
+                 'event': 'none',
+                 'iotype': 'flush'
+             }],
+             'image': {
+                 'driver': 'file',
+                 'filename': '$TEST_IMG.data'
+             }
+         }
+     }" \
+    | _filter_qemu_io
+
+result=${PIPESTATUS[0]}
+echo
+
+case $result in
+    0)
+        echo "ERROR: qemu-io succeeded, so the data file was not flushed"
+        ;;
+    1)
+        echo "Success: qemu-io failed, so the data file was flushed"
+        ;;
+    *)
+        echo "ERROR: qemu-io returned unknown exit code $result"
+        ;;
+esac
+
 # success, all done
 echo "*** done"
 rm -f $seq.full
diff --git a/tests/qemu-iotests/244.out b/tests/qemu-iotests/244.out
index dbab735..7269b42 100644
--- a/tests/qemu-iotests/244.out
+++ b/tests/qemu-iotests/244.out
@@ -131,4 +131,11 @@ Offset          Length          Mapped to       File
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=67108864 data_file=TEST_DIR/t.IMGFMT.data
 Images are identical.
 Images are identical.
+
+=== Flushing should flush the data file ===
+
+wrote 512/512 bytes at offset 0
+512 bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+Success: qemu-io failed, so the data file was flushed
 *** done
diff --git a/tests/qemu-iotests/245 b/tests/qemu-iotests/245
index ad91a6f..e60c832 100755
--- a/tests/qemu-iotests/245
+++ b/tests/qemu-iotests/245
@@ -725,7 +725,9 @@ class TestBlockdevReopen(iotests.QMPTestCase):
 
         # Detach hd2 from hd0.
         self.reopen(opts, {'backing': None})
-        self.reopen(opts, {}, "backing is missing for 'hd0'")
+
+        # Without a backing file, we can omit 'backing' again
+        self.reopen(opts)
 
         # Remove both hd0 and hd2
         result = self.vm.qmp('blockdev-del', conv_keys = True, node_name = 'hd0')
diff --git a/tests/qemu-iotests/273.out b/tests/qemu-iotests/273.out
index 87d4758..8247cba 100644
--- a/tests/qemu-iotests/273.out
+++ b/tests/qemu-iotests/273.out
@@ -32,7 +32,7 @@ Testing: -blockdev file,node-name=base,filename=TEST_DIR/t.IMGFMT.base -blockdev
                         "actual-size": SIZE,
                         "dirty-flag": false
                     },
-                    "backing-filename-format": "file",
+                    "backing-filename-format": "IMGFMT",
                     "virtual-size": 67108864,
                     "filename": "TEST_DIR/t.IMGFMT.mid",
                     "cluster-size": 65536,
@@ -112,7 +112,7 @@ Testing: -blockdev file,node-name=base,filename=TEST_DIR/t.IMGFMT.base -blockdev
                     "actual-size": SIZE,
                     "dirty-flag": false
                 },
-                "backing-filename-format": "file",
+                "backing-filename-format": "IMGFMT",
                 "virtual-size": 67108864,
                 "filename": "TEST_DIR/t.IMGFMT.mid",
                 "cluster-size": 65536,
diff --git a/tests/qemu-iotests/check b/tests/qemu-iotests/check
index 3ab859a..e14a1f3 100755
--- a/tests/qemu-iotests/check
+++ b/tests/qemu-iotests/check
@@ -44,7 +44,7 @@ then
         _init_error "failed to obtain source tree name from check symlink"
     fi
     source_iotests=$(cd "$source_iotests"; pwd) || _init_error "failed to enter source tree"
-    build_iotests=$PWD
+    build_iotests=$(readlink -f $(dirname "$0"))
 else
     # called from the source tree
     source_iotests=$PWD
diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index e197c73..64ccaf9 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -972,8 +972,12 @@ class QMPTestCase(unittest.TestCase):
 
     def wait_ready(self, drive='drive0'):
         """Wait until a BLOCK_JOB_READY event, and return the event."""
-        f = {'data': {'type': 'mirror', 'device': drive}}
-        return self.vm.event_wait(name='BLOCK_JOB_READY', match=f)
+        return self.vm.events_wait([
+            ('BLOCK_JOB_READY',
+             {'data': {'type': 'mirror', 'device': drive}}),
+            ('BLOCK_JOB_READY',
+             {'data': {'type': 'commit', 'device': drive}})
+        ])
 
     def wait_ready_and_cancel(self, drive='drive0'):
         self.wait_ready(drive=drive)
@@ -992,7 +996,7 @@ class QMPTestCase(unittest.TestCase):
         self.assert_qmp(result, 'return', {})
 
         event = self.wait_until_completed(drive=drive, error=completion_error)
-        self.assert_qmp(event, 'data/type', 'mirror')
+        self.assertTrue(event['data']['type'] in ['mirror', 'commit'])
 
     def pause_wait(self, job_id='job0'):
         with Timeout(3, "Timeout waiting for job to pause"):