virtual_disks_multivms: fix disk discovery

The tests used the disk target as identifier for the
disk inside of the VM. However, the target is not guaranteed
to show up in the guest as-is, especially given that the
/dev/XdY paths are not persistent and can change between boots.

Use instead a function that identifies a new disk inside of a VM
as the one disk that has no root mount on itself, its partitions
or volumes.

Finally, the `delete_scsi_disk` doesn't return any value so it
was always looping for the full timeout. Wrap it into a function
that confirms if both the module and device have been removed.

Signed-off-by: Sebastian Mitterle <[email protected]>

Author: smitterl

libvirt/tests/src/virtual_disks/virtual_disks_multivms.py

@@ -1,6 +1,7 @@
 import os
 import logging as log
 import aexpect
+import time
 
 from avocado.utils import process
 
@@ -11,6 +12,7 @@
 from virttest import remote
 from virttest import utils_disk
 from virttest import utils_misc
+from virttest.utils_libvirt.libvirt_disk import get_non_root_disk_name
 from virttest.utils_test import libvirt
 from virttest.libvirt_xml import vm_xml
 from virttest.libvirt_xml.devices.disk import Disk
@@ -36,6 +38,19 @@ def run(test, params, env):
     6.Confirm the test result.
     """
 
+    def _delete_scsi_disk():
+        """ Helper function for wait_for in finally """
+        libvirt.delete_scsi_disk()
+        cmd = "lsscsi|grep scsi_debug"
+        s1, _ = utils_misc.cmd_status_output(cmd,
+                                             shell=True,
+                                             ignore_status=False)
+        cmd = "lsmod|grep scsi_debug"
+        s2, _ = utils_misc.cmd_status_output(cmd,
+                                             shell=True,
+                                             ignore_status=False)
+        return s1 + s2 == 2
+
     def set_vm_controller_xml(vmxml):
         """
         Set VM scsi controller xml.
@@ -239,7 +254,8 @@ def get_vm_disk_xml(dev_type, dev_name, **options):
                         test.fail('Failed to hotplug disk device')
                     elif 0 == result and not vms_list[i]['status']:
                         test.fail('Hotplug disk device unexpectedly.')
-
+                    time.sleep(5)
+                added_disk, _ = get_non_root_disk_name(session)
                 # Check disk error_policy option in VMs.
                 if test_error_policy:
                     error_policy = vms_list[i]['disk'].driver["error_policy"]
@@ -248,7 +264,7 @@ def get_vm_disk_xml(dev_type, dev_name, **options):
                         if error_policy == "enospace":
                             cmd = ("mount /dev/%s /mnt && dd if=/dev/zero of=/mnt/test"
                                    " bs=1M count=2000 2>&1 | grep 'No space left'"
-                                   % disk_target)
+                                   % added_disk)
                             s, o = session.cmd_status_output(cmd)
                             logging.debug("error_policy in vm0 exit %s; output: %s", s, o)
                             if 0 != s:
@@ -258,15 +274,15 @@ def get_vm_disk_xml(dev_type, dev_name, **options):
                             break
 
                         if session.cmd_status("fdisk -l /dev/%s && mount /dev/%s /mnt; ls /mnt"
-                                              % (disk_target, disk_target)):
+                                              % (added_disk, added_disk)):
                             session.close()
                             test.fail("Test error_policy: "
                                       "failed to mount disk")
                     if i == 1:
                         try:
                             session0 = vms_list[0]['vm'].wait_for_login(timeout=10)
                             cmd = ("fdisk -l /dev/%s && mkfs.ext3 -F /dev/%s "
-                                   % (disk_target, disk_target))
+                                   % (added_disk, added_disk))
                             s, o = session.cmd_status_output(cmd)
                             logging.debug("error_policy in vm1 exit %s; output: %s", s, o)
                             session.close()
@@ -312,9 +328,10 @@ def _check_error():
                             test_str = "teststring"
                             # Try to write on vm0.
                             session0 = vms_list[0]['vm'].wait_for_login(timeout=10)
+                            added_disk0, _ = get_non_root_disk_name(session0)
                             cmd = ("fdisk -l /dev/%s && mount /dev/%s /mnt && echo '%s' "
                                    "> /mnt/test && umount /mnt"
-                                   % (disk_target, disk_target, test_str))
+                                   % (added_disk0, added_disk0, test_str))
                             s, o = session0.cmd_status_output(cmd)
                             logging.debug("session in vm0 exit %s; output: %s", s, o)
                             if s:
@@ -323,7 +340,7 @@ def _check_error():
                             # Try to read on vm1.
                             cmd = ("fdisk -l /dev/%s && mount /dev/%s /mnt && grep %s"
                                    " /mnt/test && umount /mnt"
-                                   % (disk_target, disk_target, test_str))
+                                   % (added_disk, added_disk, test_str))
                             s, o = session.cmd_status_output(cmd)
                             logging.debug("session in vm1 exit %s; output: %s", s, o)
                             if s:
@@ -377,7 +394,7 @@ def _check_error():
         for img in disks:
             if 'format' in img:
                 if img["format"] == "scsi":
-                    utils_misc.wait_for(libvirt.delete_scsi_disk,
+                    utils_misc.wait_for(_delete_scsi_disk,
                                         120, ignore_errors=True)
                 elif img["format"] == "iscsi":
                     libvirt.setup_or_cleanup_iscsi(is_setup=False)