[PATCH v4 0/2] nvme: Add fault injection feature

[thomas.tai@oracle.com (Thomas Tai)]

Linux's fault injection framework provides a systematic way to support
error injection via debugfs in the /sys/kernel/debug directory. This
patch uses the framework to add error injection to NVMe driver. 

Change log since last version:
from v3 to v4:
- correct documentation to cover status code can be changed
  via debugfs
- add Reviewed-by: Keith Busch <keith.busch at intel.com>

from v1 to V2:
- add user changable status and no_retry debugfs attribute
- add document to show how to use nvme fault injection

from v0 to V1:
- move error injection point into nvme_end_request()
- Add expected result in the commit log

Thank you,
Thomas