This behavior is already documented by the man page, and suggested by POSIX.
Reviewed by: jhb
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D15099
Our man pages have always indicated that this was supported, but in fact the
feature was never implemented for lio_listio(2).
Reviewed by: jhb, kib (earlier version)
MFC after: 20 days
Sponsored by: Spectra Logic Corp
Differential Revision: https://reviews.freebsd.org/D11680