Re: SCSI device numbering

Alexandre Maret (amaret@infomaniak.ch)
Tue, 02 Jul 1996 01:40:39 +0200

Johnie Stafford wrote:
>
> >>>>> "ac" == Albert Cahalan <albert@ccs.neu.edu> writes:
>
> ac> No, it is sufficient for everything, including really weird
> ac> SCSI adapters. Using nibble boundries (for nice hex output),
> ac> dev_t can be split as follows:
>
> ac> Purpose Bits Normal Extreme
> ac> controller 4 <= 1 2
> ac> bus 4 == 0 1
> ac> device 8 <= 2 4
>
> What about wide SCSI? It does 16 devices.

sorry... that's 8 bits -> 256 devices. It should be enough for
your ultra-giga-wide-SCSI ;-)

> ac> lun 8 == 0 3
> ac> partition 4 <= 3 4
>
> What about an entry for the entire disk (eg. /dev/sda)? What about
> logical partitions? If you include the entry for the entire disk, I
> use 9 entries for my primary disk.

4**2 = 16 is enough for 15 partitions + the whole disk

> Johnie

PS : shouldn't this message go to linux-scsi instead ??

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