Fujitsu 1.2Gb disk on Sun

[Chris Torek]

The `magic limit' for old SCSI is 2 097 152 blocks.  These drives have
512-byte blocks, so that is 1 073 741 824 bytes.  This limit occurs
because the 6-byte SCSI read and write commands store the block number
in 21 bits.

The solution is to use the 10-byte SCSI read and write commands, which
have a 32 bit field and can address 4 294 967 296 blocks or, with 512
byte blocks) 2 199 023 255 552 (2 terabytes).  With 1024 byte blocks
the addressibility doubles; the 10-byte command are unlikely to be a
problem for some time.

How many SCSI disk controllers (targets) do *not* support 10-byte
commands?  My driver assumes all disks do, for now, but it would be
easy to choose 6-or-10 based on the capacity returned or, if necessary,
each block number.
-- 
In-Real-Life: Chris Torek, Lawrence Berkeley Lab CSE/EE (+1 415 486 5427)
Berkeley, CA		Domain:	torek at ee.lbl.gov