tree 0b8ad8262b8294e22ba0abc9d289e4844077acba
parent 3c6829009ec5978d63b78060ca8e4e08c4e75a6b
author Venkatesh Srinivas <venkateshs@google.com> 1548714881 -0500
committer CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org> 1548725571 +0000

[virtio] scsi: Fix encoding of LUNs

virtio-scsi requires Target/LUN pairs be encoded into an 8-byte buffer
in a particular format --

1. First byte set to 1
2. Second byte set to target
3. Third and fourth byte representing a 'single level LUN structure'

Per the SCSI Architecture Manual, the single-level format we should
be using is the flat addressing method (table 6, SAM-3 T10/02-119r0) or
(tabel 9, Flat space addressing, SAM-3 T10/02-119r0).

Bits 7-6 of the low byte should be '01'. Then we should pack the 6 MSBs
of the LUN into the low byte and the 8 LSBs into the high byte.

The prior version of this code did not set the address method (implicit
Peripheral device address method) and incorrectly mashed the LUN for
that mode.

ZX-2314

Tested: With the correct loop condition CR, booted on GCE and QEMU.
Tested that expected LUNs were found and bound to virtio.so

Change-Id: I6b4a53ea16dec0962233d143660744edd012dfc8