CCISS(4)						     Linux Programmer's Manual							  CCISS(4)

NAME

       cciss - HP Smart Array block driver

SYNOPSIS

       modprobe cciss [ cciss_allow_hpsa=1 ]

DESCRIPTION

       cciss is a block driver for older HP Smart Array RAID controllers.

   Options
       cciss_allow_hpsa=1:  This  option  prevents the cciss driver from attempting to drive any controllers that the hpsa(4) driver is capable of
       controlling, which is to say, the cciss driver is restricted by this option to the following controllers:

	   Smart Array 5300
	   Smart Array 5i
	   Smart Array 532
	   Smart Array 5312
	   Smart Array 641
	   Smart Array 642
	   Smart Array 6400
	   Smart Array 6400 EM
	   Smart Array 6i
	   Smart Array P600
	   Smart Array P400i
	   Smart Array E200i
	   Smart Array E200
	   Smart Array E200i
	   Smart Array E200i
	   Smart Array E200i
	   Smart Array E500

   Supported hardware
       The cciss driver supports the following Smart Array boards:

	   Smart Array 5300
	   Smart Array 5i
	   Smart Array 532
	   Smart Array 5312
	   Smart Array 641
	   Smart Array 642
	   Smart Array 6400
	   Smart Array 6400 U320 Expansion Module
	   Smart Array 6i
	   Smart Array P600
	   Smart Array P800
	   Smart Array E400
	   Smart Array P400i
	   Smart Array E200
	   Smart Array E200i
	   Smart Array E500
	   Smart Array P700m
	   Smart Array P212
	   Smart Array P410
	   Smart Array P410i
	   Smart Array P411
	   Smart Array P812
	   Smart Array P712m
	   Smart Array P711m

   Configuration details
       To configure HP Smart Array controllers, use the HP Array Configuration Utility (either hpacuxe(8) or hpacucli(8)) or the Offline ROM-based
       Configuration Utility (ORCA) run from the Smart Array's option ROM at boot time.

FILES

   Device nodes
       The device naming scheme is as follows:

       Major numbers:

	   104	   cciss0
	   105	   cciss1
	   106	   cciss2
	   105	   cciss3
	   108	   cciss4
	   109	   cciss5
	   110	   cciss6
	   111	   cciss7

       Minor numbers:

	   b7 b6 b5 b4 b3 b2 b1 b0
	   |----+----| |----+----|
		|	    |
		|	    +-------- Partition ID (0=wholedev, 1-15 partition)
		|
		+-------------------- Logical Volume number

       The device naming scheme is:

	   /dev/cciss/c0d0	   Controller 0, disk 0, whole device
	   /dev/cciss/c0d0p1	   Controller 0, disk 0, partition 1
	   /dev/cciss/c0d0p2	   Controller 0, disk 0, partition 2
	   /dev/cciss/c0d0p3	   Controller 0, disk 0, partition 3

	   /dev/cciss/c1d1	   Controller 1, disk 1, whole device
	   /dev/cciss/c1d1p1	   Controller 1, disk 1, partition 1
	   /dev/cciss/c1d1p2	   Controller 1, disk 1, partition 2
	   /dev/cciss/c1d1p3	   Controller 1, disk 1, partition 3

   Files in /proc
       The files /proc/driver/cciss/cciss[0-9]+ contain information about the configuration of each controller.  For example:

	   $ cd /proc/driver/cciss
	   $ ls -l
	   total 0
	   -rw-r--r-- 1 root root 0 2010-09-10 10:38 cciss0
	   -rw-r--r-- 1 root root 0 2010-09-10 10:38 cciss1
	   -rw-r--r-- 1 root root 0 2010-09-10 10:38 cciss2
	   $ cat cciss2
	   cciss2: HP Smart Array P800 Controller
	   Board ID: 0x3223103c
	   Firmware Version: 7.14
	   IRQ: 16
	   Logical drives: 1
	   Current Q depth: 0
	   Current # commands on controller: 0
	   Max Q depth since init: 1
	   Max # commands on controller since init: 2
	   Max SG entries since init: 32
	   Sequential access devices: 0

	   cciss/c2d0:	 36.38GB       RAID 0

   Files in /sys
       /sys/bus/pci/devices/<dev>/ccissX/cXdY/model
	      Displays the SCSI INQUIRY page 0 model for logical drive Y of controller X.

       /sys/bus/pci/devices/<dev>/ccissX/cXdY/rev
	      Displays the SCSI INQUIRY page 0 revision for logical drive Y of controller X.

       /sys/bus/pci/devices/<dev>/ccissX/cXdY/unique_id
	      Displays the SCSI INQUIRY page 83 serial number for logical drive Y of controller X.

       /sys/bus/pci/devices/<dev>/ccissX/cXdY/vendor
	      Displays the SCSI INQUIRY page 0 vendor for logical drive Y of controller X.

       /sys/bus/pci/devices/<dev>/ccissX/cXdY/block:cciss!cXdY
	      A symbolic link to /sys/block/cciss!cXdY.

       /sys/bus/pci/devices/<dev>/ccissX/rescan
	      When this file is written to, the driver rescans the controller to discover any new, removed, or modified logical drives.

       /sys/bus/pci/devices/<dev>/ccissX/resettable
	      A  value	of  1 displayed in this file indicates that the "reset_devices=1" kernel parameter (used by kdump) is honored by this con-
	      troller.	A value of 0 indicates that the "reset_devices=1" kernel parameter will not be honored.  Some models of  Smart	Array  are
	      not able to honor this parameter.

       /sys/bus/pci/devices/<dev>/ccissX/cXdY/lunid
	      Displays the 8-byte LUN ID used to address logical drive Y of controller X.

       /sys/bus/pci/devices/<dev>/ccissX/cXdY/raid_level
	      Displays the RAID level of logical drive Y of controller X.

       /sys/bus/pci/devices/<dev>/ccissX/cXdY/usage_count
	      Displays the usage count (number of opens) of logical drive Y of controller X.

   SCSI tape drive and medium changer support
       SCSI  sequential  access  devices  and  medium  changer devices are supported and appropriate device nodes are automatically created (e.g.,
       /dev/st0, /dev/st1, etc.; see st(4) for more details.)  You must enable "SCSI tape drive support for Smart Array 5xxx" and  "SCSI  support"
       in your kernel configuration to be able to use SCSI tape drives with your Smart Array 5xxx controller.

       Additionally,  note that the driver will not engage the SCSI core at init time.	The driver must be directed to dynamically engage the SCSI
       core via the /proc filesystem entry, which the "block" side of the driver creates  as  /proc/driver/cciss/cciss*  at  run  time.   This	is
       because	at driver init time, the SCSI core may not yet be initialized (because the driver is a block driver) and attempting to register it
       with the SCSI core in such a case would cause a hang.  This is best done via an initialization script (typically in /etc/init.d, but  could
       vary depending on distribution).  For example:

	   for x in /proc/driver/cciss/cciss[0-9]*
	   do
	       echo "engage scsi" > $x
	   done

       Once  the SCSI core is engaged by the driver, it cannot be disengaged (except by unloading the driver, if it happens to be linked as a mod-
       ule.)

       Note also that if no sequential access devices or medium changers are detected, the SCSI core will not be engaged  by  the  action  of  the
       above script.

   Hot plug support for SCSI tape drives
       Hot plugging of SCSI tape drives is supported, with some caveats.  The cciss driver must be informed that changes to the SCSI bus have been
       made.  This may be done via the /proc filesystem.  For example:

	   echo "rescan" > /proc/scsi/cciss0/1

       This causes the driver to:

	      1. query the adapter about changes to the physical SCSI buses and/or fibre channel arbitrated loop, and

	      2. make note of any new or removed sequential access devices or medium changers.

       The driver will output messages indicating which devices have been added or removed and the  controller,  bus,  target,	and  lun  used	to
       address each device.  The driver then notifies the SCSI midlayer of these changes.

       Note that the naming convention of the /proc filesystem entries contains a number in addition to the driver name (e.g., "cciss0" instead of
       just "cciss", which you might expect).

       Note: Only sequential access devices and medium changers are presented as SCSI devices to the SCSI midlayer by the cciss driver.   Specifi-
       cally,  physical SCSI disk drives are not presented to the SCSI midlayer.  The only disk devices that are presented to the kernel are logi-
       cal drives that the array controller constructs from regions on the physical drives.  The logical drives are presented to the  block  layer
       (not  to the SCSI midlayer).  It is important for the driver to prevent the kernel from accessing the physical drives directly, since these
       drives are used by the array controller to construct the logical drives.

   SCSI error handling for tape drives and medium changers
       The Linux SCSI midlayer provides an error-handling protocol that is initiated whenever a SCSI command fails to complete	within	a  certain
       amount  of time (which can vary depending on the command).  The cciss driver participates in this protocol to some extent.  The normal pro-
       tocol is a four-step process:

       *  First, the device is told to abort the command.

       *  If that doesn't work, the device is reset.

       *  If that doesn't work, the SCSI bus is reset.

       *  If that doesn't work, the host bus adapter is reset.

       The cciss driver is a block driver as well as a SCSI driver and only the tape drives and medium changers are presented  to  the	SCSI  mid-
       layer.	Furthermore,  unlike  more  straightforward SCSI drivers, disk I/O continues through the block side during the SCSI error-recovery
       process.  Therefore, the cciss driver implements only the first two of these actions, aborting the command, and resetting the device.  Note
       also  that  most tape drives will not oblige in aborting commands, and sometimes it appears they will not even obey a reset command, though
       in most circumstances they will.  If the command cannot be aborted and the device cannot be reset, the device will be set offline.

       In the event that the error-handling code is triggered and a tape drive is successfully reset or the tardy command is successfully aborted,
       the tape drive may still not allow I/O to continue until some command is issued that positions the tape to a known position.  Typically you
       must rewind the tape (by issuing mt -f /dev/st0 rewind for example) before I/O can proceed again to a tape drive that was reset.

SEE ALSO

       cciss_vol_status(8), hpsa(4), hpacucli(8), hpacuxe(8),

       <http://cciss.sf.net>, and Documentation/blockdev/cciss.txt and Documentation/ABI/testing/sysfs-bus-pci-devices-cciss in the  Linux  kernel
       source tree

Linux								    2012-08-05								  CCISS(4)