1 This driver is for Compaq's SMART Array Controllers.
6 This driver is known to work with the following cards:
15 * SA 6400 U320 Expansion Module
17 If nodes are not already created in the /dev/cciss directory
21 Where ctlrs is the number of controllers you have (defaults to 1 if not
27 You need some entries in /dev for the cciss device. The mkdev.cciss script
28 can make device nodes for you automatically. Currently the device setup
38 b7 b6 b5 b4 b3 b2 b1 b0
39 |----+----| |----+----|
41 | +-------- Partition ID (0=wholedev, 1-15 partition)
43 +-------------------- Logical Volume number
45 The suggested device naming scheme is:
46 /dev/cciss/c0d0 Controller 0, disk 0, whole device
47 /dev/cciss/c0d0p1 Controller 0, disk 0, partition 1
48 /dev/cciss/c0d0p2 Controller 0, disk 0, partition 2
49 /dev/cciss/c0d0p3 Controller 0, disk 0, partition 3
51 /dev/cciss/c1d1 Controller 1, disk 1, whole device
52 /dev/cciss/c1d1p1 Controller 1, disk 1, partition 1
53 /dev/cciss/c1d1p2 Controller 1, disk 1, partition 2
54 /dev/cciss/c1d1p3 Controller 1, disk 1, partition 3
56 SCSI tape drive and medium changer support
57 ------------------------------------------
59 SCSI sequential access devices and medium changer devices are supported and
60 appropriate device nodes are automatically created. (e.g.
61 /dev/st0, /dev/st1, etc. See the "st" man page for more details.)
62 You must enable "SCSI tape drive support for Smart Array 5xxx" and
63 "SCSI support" in your kernel configuration to be able to use SCSI
64 tape drives with your Smart Array 5xxx controller.
66 Additionally, note that the driver will not engage the SCSI core at init
67 time. The driver must be directed to dynamically engage the SCSI core via
68 the /proc filesystem entry which the "block" side of the driver creates as
69 /proc/driver/cciss/cciss* at runtime. This is because at driver init time,
70 the SCSI core may not yet be initialized (because the driver is a block
71 driver) and attempting to register it with the SCSI core in such a case
72 would cause a hang. This is best done via an initialization script
73 (typically in /etc/init.d, but could vary depending on distibution).
76 for x in /proc/driver/cciss/cciss[0-9]*
78 echo "engage scsi" > $x
81 Once the SCSI core is engaged by the driver, it cannot be disengaged
82 (except by unloading the driver, if it happens to be linked as a module.)
84 Note also that if no sequential access devices or medium changers are
85 detected, the SCSI core will not be engaged by the action of the above
88 Hot plug support for SCSI tape drives
89 -------------------------------------
91 Hot plugging of SCSI tape drives is supported, with some caveats.
92 The cciss driver must be informed that changes to the SCSI bus
93 have been made, in addition to and prior to informing the SCSI
94 mid layer. This may be done via the /proc filesystem. For example:
96 echo "rescan" > /proc/scsi/cciss0/1
98 This causes the adapter to query the adapter about changes to the
99 physical SCSI buses and/or fibre channel arbitrated loop and the
100 driver to make note of any new or removed sequential access devices
101 or medium changers. The driver will output messages indicating what
102 devices have been added or removed and the controller, bus, target and
103 lun used to address the device. Once this is done, the SCSI mid layer
104 can be informed of changes to the virtual SCSI bus which the driver
105 presents to it in the usual way. For example:
107 echo scsi add-single-device 3 2 1 0 > /proc/scsi/scsi
109 to add a device on controller 3, bus 2, target 1, lun 0. Note that
110 the driver makes an effort to preserve the devices positions
111 in the virtual SCSI bus, so if you are only moving tape drives
112 around on the same adapter and not adding or removing tape drives
113 from the adapter, informing the SCSI mid layer may not be necessary.
115 Note that the naming convention of the /proc filesystem entries
116 contains a number in addition to the driver name. (E.g. "cciss0"
117 instead of just "cciss" which you might expect.) This is because
118 of changes to the 2.4 kernel PCI interface related to PCI hot plug
119 that imply the driver must register with the SCSI mid layer once per
120 adapter instance rather than once per driver.
122 Note: ONLY sequential access devices and medium changers are presented
123 as SCSI devices to the SCSI mid layer by the cciss driver. Specifically,
124 physical SCSI disk drives are NOT presented to the SCSI mid layer. The
125 physical SCSI disk drives are controlled directly by the array controller
126 hardware and it is important to prevent the OS from attempting to directly
127 access these devices too, as if the array controller were merely a SCSI
128 controller in the same way that we are allowing it to access SCSI tape drives.