ciss -- Common Interface for SCSI-3 Support driver
device scbus
device ciss
The ciss driver claims to provide a common interface between generic SCSI
transports and intelligent host adapters.
The ciss driver supports CISS as defined in the document entitled CISS
Command Interface for SCSI-3 Support Open Specification, Version 1.04,
Valence Number 1, dated 2000/11/27, produced by Compaq Computer Corporation.
We provide a shim layer between the ciss interface and CAM(4), offloading
most of the queueing and being-a-disk chores onto CAM. Entry to the
driver is via the PCI bus attachment ciss_probe(), ciss_attach(), etc.
and via the CAM interface ciss_cam_action(), and ciss_cam_poll(). The
Compaq ciss adapters require faked responses to get reasonable behavior
out of them. In addition, the ciss command set is by no means adequate
to support the functionality of a RAID controller, and thus the supported
Compaq adapters utilize portions of the control protocol from earlier
Compaq adapter families.
Currently ciss only supports the ``simple'' transport layer over PCI.
This interface (ab)uses the I2O register set (specifically the post
queues) to exchange commands with the adapter. Other interfaces are
available, but we are not supposed to know about them, and it is dubious
whether they would provide major performance improvements except under
extreme load.
Non-disk devices (such as internal DATs and devices attached to the
external SCSI bus) are not yet supported.
Supported controllers include:
Compaq Smart Array 5300
Compaq Smart Array 532
Compaq Smart Array 5i
HP Smart Array 5312
HP Smart Array 6i
HP Smart Array 641
HP Smart Array 642
HP Smart Array 6400
HP Smart Array 6400 EM
cam(4), pass(4), xpt(4), camcontrol(8)
CISS Command Interface for SCSI-3 Support Open Specification, Version
1.04, Valence Number 1, Compaq Computer Corporation, 2000/11/27.
The ciss driver was written by Mike Smith <[email protected]>.
This manual page is based on his comments and was written by Tom Rhodes
<[email protected]>.
FreeBSD 5.2.1 December 29, 2002 FreeBSD 5.2.1 [ Back ] |
