Added dd definition to error

this definition is used to check destrctive revert operation

This definition was missed in ealier push in avocado utils

same definition can be used to read required number of blocks
from provided input file from any kind of block device

Signed-off-by: Maram Srimannarayana Murthy <msmurthy@linux.vnet.ibm.com>

Author: maramsmurthy

io/disk/ssd/nvme_sedtest.py

@@ -24,7 +24,6 @@
 import time
 
 from avocado import Test
-from avocado.utils import disk
 from avocado.utils import nvme
 from avocado.utils import process
 from avocado.utils.software_manager.manager import SoftwareManager
@@ -121,6 +120,17 @@ def is_drive_locked(self, namespace):
         lockdown_attr = self.get_nvme_sed_discover_parameters(namespace)
         return lockdown_attr.get("Locked").lower() == "yes"
 
+    def dd_read_records_device(self, disk, read_records="1", out_file="/tmp/data"):
+        """
+        Reads mentioned number of blocks from device to destination
+        :param disk: disk absolute path
+        :param read_records: Numbers of blocks to read from disk
+        :param out_file: Destination file
+        :rtype: boolean
+        """
+        cmd = f"dd count={read_records} if={disk} of={out_file}"
+        return not process.system(cmd, ignore_status=True, sudo=True)
+
     def initialize_sed_locking(self, namespace, password):
         """
         Enables and initializes SED feature on nvme disk
@@ -256,21 +266,21 @@ def lock_unlock(self):
         Perform lock and unlock of nvme drive
         """
         self.lock_drive(self.namespace)
-        if disk.dd_read_records_device(self.namespace):
+        if self.dd_read_records_device(self.namespace):
             self.log.fail(f"dd read command on {self.namespace} is successful, dd should fail when drive is locked")
         self.unlock_drive(self.namespace)
-        if not disk.dd_read_records_device(self.namespace):
+        if not self.dd_read_records_device(self.namespace):
             self.log.fail(f"dd read command on {self.namespace} is failed, dd should success when drive is unlocked")
 
     def lock_unlock_with_key(self, password):
         """
         Perform lock and unlock with provided key
         """
         self.lock_drive(self.namespace, with_pass_key=password)
-        if disk.dd_read_records_device(self.namespace):
+        if self.dd_read_records_device(self.namespace):
             self.log.fail(f"dd read command on {self.namespace} is successful, dd should fail when drive is locked")
         self.unlock_drive(self.namespace, with_pass_key=password)
-        if not disk.dd_read_records_device(self.namespace):
+        if not self.dd_read_records_device(self.namespace):
             self.log.fail(f"dd read command on {self.namespace} is failed, dd should success when drive is unlocked")
 
     def test_initialize_locking(self):