[techomancer]

The O2 read its disks from its own o2.disks list and ignored the [scsi.N] tables, so changer lists, scratch volumes, CHD images, CI overlays and the --scsi1/--cdrom4 options never reached it, and the monitor's scsi command did not exist there: it was implemented inside the WD33C93A.

Configuration. Both machines now attach their devices from [scsi.N]. controller names the bus on the O2 as it does on the Indigo2 (0 internal, 1 external); the validator accepts controller 1 on both and refuses a DaynaPort on the O2, whose Ethernet is built in. The key is a slot: N 1-7 is id N on controller 0, N = 16 + id is that id on controller 1, so [scsi.1] and [scsi.17] put a disk at id 1 on each controller; controller = 1 on a low key still works, a slot key contradicted by controller, two tables naming one target, id 0 and controller 2 are refused. Snapshot manifests record disks by slot. o2.disks is deprecated: load_toml folds it into [scsi.N] and says so. The changer-list, CI-overlay-path and scratch-volume logic the Indy loop had inline is now on ScsiDeviceConfig and shared; the Indy loop also honours kind = "cdrom" without cdrom = true. An O2 image that will not open ends the run as on the Indy (an embedder boots without it).

Monitor. src/scsi_monitor.rs implements scsi status, scsi dayna, the changer subcommands, the whole of cow and the DiscChanger operations once, over a controller's target table lent through its ScsiTargets trait. The WD33C93A keeps regs, wdt, defer and debug; the Adaptec 7880 keeps regs (its interrupt status, queues and totals). DiscChanger has one blanket impl over ScsiTargets. On the O2, controller 0 answers to scsi/scsi0/cow and controller 1 to scsi1/cow1; both controllers are registered with the monitor. scsi status lists disks as well as CD-ROMs. The O2 also gains scratch_path and disc_changer, so iris-ci's scratch and cdrom commands and the window's disc change work there.

Docs: HELP.md, FEATURES.md, debug.md, HACKING.md, docs/o2-ip32.md, docs/indigo2-ip22.md, iris.toml, CHANGELOG.md. Tests: slot placement and its refusals, the O2 controller rule, the o2.disks fold.