Update the order of importing modules by PEP8.

Wrap the codes to function:
  1. Update function find_disk and rename it.
  2. Update function run_sub_test.
  3. Wrap the part of waiting plugging disks completely to
     function wait_plug_disks.
  4. Wrap the part of creating block devices to function
     create_block_devices.
  5. Wrap the part of getting block devices to function
     get_block_devices.
  6. Wrap the part of hotplug or unplug block devices to
     function plug_block_devices.
  7. Wrap the part of format windows disk to function format_disk_win.
  8. Wrap the part of doing io testing on disk to function
     run_io_test.
  9. Update function get_disk_size.
Signed-off-by: NYongxue Hong <yhong@redhat.com>

Need to update the block cases to support blockdev options, since
qemu enable the blockdev options from the certain version.

Updated cases:
 1. block_hotplug
 2. block_resize
 3. cdrom
 4. cdrom_block_size_check
 5. change_media
 6. eject_media
 7. block_hotplug_in_pause
 8. multi_disk_random_hotplug
Signed-off-by: NYongxue Hong <yhong@redhat.com>

Add a case that hotplug a max image size disk with qcow2 and raw.
Signed-off-by: NYongxue Hong <yhong@redhat.com>

Fix up the filedescriptor out of range in select()
by reducing to call the wait_for_login.
Signed-off-by: NYongxue Hong <yhong@redhat.com>

block_hotplug:Correct "dev" to "device"
Signed-off-by: NAihua Liang <aliang@redhat.com>

block_hotplug:
1.replace hotplug device definations by qcontainer.images_define_
by_params()
2.remove useless options in block_hotplug.cfg
3.replace hotplug/verify_hot|unplug by simple_hot|unplug()
4.extract sub_tests to run_sub_test()
Signed-off-by: NAihua Liang <aliang@redhat.com>

Signed-off-by: NXu Han <xuhan@redhat.com>

Signed-off-by: NXu Han <xuhan@redhat.com>

Add subtest "block_resize" after hotplug.
Signed-off-by: NAihua Liang <aliang@redhat.com>

If the vm is truly crash/dead, original code will return directly, which is not expected. Only for screnaio 'shutdown' could return directly, others should prompt guest dead error info which is already added in the framework.
Signed-off-by: NCong Li <coli@redhat.com>

block_hotplug:add code to unplug virtio-scsi-pci.
Signed-off-by: NAihua Liang <aliang@redhat.com>

data plane support for case "with_plug.with_system_reset.one_pci"
Signed-off-by: NAihua Liang <aliang@redhat.com>

Run iozone test on hotpluged data disk on windows guests.
Add test case reboot and shutdown guest after hotplug a data disk.
Signed-off-by: Npeixiu <phou@redhat.com>

1. block_hotplug.cfg: add separate scenario for repeated plug/unplug, no need repeat 300 times for each scenario when one pci.
2. block_hotplug.py: get and close a separate session when using it to fix file descriptor out of range problem.
3. stop_continue.py: close session when test finished.
Signed-off-by: NCong Li <coli@redhat.com>

Add new case for block_hotplug, support block_virtio and
block_scsi with hotplug/unplug.
Signed-off-by: NShuping Cui <scui@redhat.com>