This change is based on Linux commit 40630f462824ee. csio.resid should
account for transfer_len only for success and SRB_STATUS_DATA_OVERRUN
condition.
I am not sure how exactly this change works, but I have a report from a
user that they see lots of checksum errors when running a pool scrub
concurrently with iozone -l 1 -s 100G. After applying this patch the
problem cannot be reproduced.
Reviewed by: nobody
Sponsored by: CyberSecure
Differential Revision: https://reviews.freebsd.org/D22312
efdba95d62