Rescan device after filesystem creation

In work_on_disk function, IPA runs mkfs commands without
following device rescan operation. This leads to incorrect
content of uuids_to_return to be returned.
These mkfs commands modify partition label but IPA fails
to catch such changes because of no following device
rescan operation.

This commit adds call of device rescan function before
uuids_to_return construction.

Change-Id: I4e8b30deb5e2247f51ce8f10bd3271f64a264089
(cherry picked from commit fa70a1909b0f60e1c2c804cb28765fd989ed3fb9)

3 files changed, 21 insertions, 4 deletions

diff --git a/ironic_python_agent/partition_utils.py b/ironic_python_agent/partition_utils.py
index 498fb284..8e03919b 100644
--- a/ironic_python_agent/partition_utils.py
+++ b/ironic_python_agent/partition_utils.py
@@ -312,6 +312,9 @@ def work_on_disk(dev, root_mb, swap_mb, ephemeral_mb, ephemeral_format,
                  "formatted for node %(node)s",
                  {'ephemeral': ephemeral_part, 'node': node_uuid})
 
+    # Rescan device to get current status (e.g. reflect modification of mkfs)
+    disk_utils.trigger_device_rescan(dev)
+
     uuids_to_return = {
         'root uuid': root_part,
         'efi system partition uuid': part_dict.get('efi system partition'),
diff --git a/ironic_python_agent/tests/unit/test_partition_utils.py b/ironic_python_agent/tests/unit/test_partition_utils.py
index 64316dc0..0064acde 100644
--- a/ironic_python_agent/tests/unit/test_partition_utils.py
+++ b/ironic_python_agent/tests/unit/test_partition_utils.py
@@ -406,6 +406,8 @@ class WorkOnDiskTestCase(base.IronicAgentTest):
                                              cpu_arch="")
         mock_unlink.assert_called_once_with('fake-path')
 
+    @mock.patch.object(disk_utils, 'trigger_device_rescan',
+                       lambda d: None)
     @mock.patch.object(utils, 'mkfs', lambda fs, path, label=None: None)
     @mock.patch.object(disk_utils, 'block_uuid', lambda p: 'uuid')
     @mock.patch.object(disk_utils, 'populate_image', autospec=True)
@@ -440,6 +442,8 @@ class WorkOnDiskTestCase(base.IronicAgentTest):
         self.assertEqual('uuid', res['root uuid'])
         self.assertFalse(mock_populate.called)
 
+    @mock.patch.object(disk_utils, 'trigger_device_rescan',
+                       lambda d: None)
     @mock.patch.object(utils, 'mkfs', lambda fs, path, label=None: None)
     @mock.patch.object(disk_utils, 'block_uuid', lambda p: 'uuid')
     @mock.patch.object(disk_utils, 'populate_image', lambda image_path,
@@ -473,11 +477,12 @@ class WorkOnDiskTestCase(base.IronicAgentTest):
                                              disk_label='gpt',
                                              cpu_arch="")
 
+    @mock.patch.object(disk_utils, 'trigger_device_rescan', autospec=True)
     @mock.patch.object(disk_utils, 'block_uuid', autospec=True)
     @mock.patch.object(disk_utils, 'populate_image', autospec=True)
     @mock.patch.object(utils, 'mkfs', autospec=True)
     def test_uefi_localboot(self, mock_mkfs, mock_populate_image,
-                            mock_block_uuid):
+                            mock_block_uuid, mock_trigger_device_rescan):
         """Test that we create a fat filesystem with UEFI localboot."""
         root_part = '/dev/fake-part1'
         efi_part = '/dev/fake-part2'
@@ -508,12 +513,14 @@ class WorkOnDiskTestCase(base.IronicAgentTest):
                                                     root_part, conv_flags=None)
         mock_block_uuid.assert_any_call(root_part)
         mock_block_uuid.assert_any_call(efi_part)
+        mock_trigger_device_rescan.assert_called_once_with(self.dev)
 
+    @mock.patch.object(disk_utils, 'trigger_device_rescan', autospec=True)
     @mock.patch.object(disk_utils, 'block_uuid', autospec=True)
     @mock.patch.object(disk_utils, 'populate_image', autospec=True)
     @mock.patch.object(utils, 'mkfs', autospec=True)
     def test_preserve_ephemeral(self, mock_mkfs, mock_populate_image,
-                                mock_block_uuid):
+                                mock_block_uuid, mock_trigger_device_rescan):
         """Test that ephemeral partition doesn't get overwritten."""
         ephemeral_part = '/dev/fake-part1'
         root_part = '/dev/fake-part2'
@@ -541,11 +548,12 @@ class WorkOnDiskTestCase(base.IronicAgentTest):
                                              cpu_arch="")
         self.assertFalse(mock_mkfs.called)
 
+    @mock.patch.object(disk_utils, 'trigger_device_rescan', autospec=True)
     @mock.patch.object(disk_utils, 'block_uuid', autospec=True)
     @mock.patch.object(disk_utils, 'populate_image', autospec=True)
     @mock.patch.object(utils, 'mkfs', autospec=True)
     def test_ppc64le_prep_part(self, mock_mkfs, mock_populate_image,
-                               mock_block_uuid):
+                               mock_block_uuid, mock_trigger_device_rescan):
         """Test that PReP partition uuid is returned."""
         prep_part = '/dev/fake-part1'
         root_part = '/dev/fake-part2'
@@ -571,11 +579,12 @@ class WorkOnDiskTestCase(base.IronicAgentTest):
                                              cpu_arch="ppc64le")
         self.assertFalse(mock_mkfs.called)
 
+    @mock.patch.object(disk_utils, 'trigger_device_rescan', autospec=True)
     @mock.patch.object(disk_utils, 'block_uuid', autospec=True)
     @mock.patch.object(disk_utils, 'populate_image', autospec=True)
     @mock.patch.object(utils, 'mkfs', autospec=True)
     def test_convert_to_sparse(self, mock_mkfs, mock_populate_image,
-                               mock_block_uuid):
+                               mock_block_uuid, mock_trigger_device_rescan):
         ephemeral_part = '/dev/fake-part1'
         swap_part = '/dev/fake-part2'
         root_part = '/dev/fake-part3'
diff --git a/releasenotes/notes/rescan-device-after-mkfs-3f9d52a2e3b6fff3.yaml b/releasenotes/notes/rescan-device-after-mkfs-3f9d52a2e3b6fff3.yaml
new file mode 100644
index 00000000..3a8d9e08
--- /dev/null
+++ b/releasenotes/notes/rescan-device-after-mkfs-3f9d52a2e3b6fff3.yaml
@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    Adds device rescan operation after partitioning the root device to ensure
+    that updated UUIDs are reflected correctly