man > cciss(4)

cciss(4)                              Kernel Interfaces Manual                              cciss(4)

NAME
       cciss - HP Smart Array block driver

SYNOPSIS
       modprobe cciss [ cciss_allow_hpsa=1 ]

DESCRIPTION
       Note: This obsolete driver was removed in Linux 4.14, as it is superseded by the hpsa(4) dri‐
       ver in newer kernels.

       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 con‐
       trollers 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 para‐
              meter (used by kdump) is honored by this controller.  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  de‐
       vice  nodes are automatically created (e.g., /dev/st0, /dev/st1, etc.; see st(4) for more de‐
       tails.)  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  con‐
       troller.

       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 be‐
       cause  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 module.)

       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  fiber  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.  Specifically, physical SCSI disk drives are not presented
       to  the  SCSI  midlayer.   The only disk devices that are presented to the kernel are logical
       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 proto‐
       col is a four-step process:

       (1)  First, the device is told to abort the command.

       (2)  If that doesn't work, the device is reset.

       (3)  If that doesn't work, the SCSI bus is reset.

       (4)  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 midlayer.  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,  abort‐
       ing  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 can‐
       not 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 con‐
       tinue 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 pro‐
       ceed again to a tape drive that was reset.

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

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

Linux man-pages 6.7                          2023-10-31                                     cciss(4)