 |
Index for
Section 4 |
|
 |
Alphabetical
listing for D |
|
 |
Bottom of
page |
|
ddr.dbase(4)
NAME
ddr.dbase - Text database file of SCSI CAM device definitions
SYNOPSIS
/etc/ddr.dbase
DESCRIPTION
Dynamic Device Recognition (DDR) is a framework for describing the
operating parameters and characteristics of SCSI devices to the SCSI CAM
I/O subsystem. You use a utility, /sbin/ddr_config, and a text database,
/etc/ddr.dbase, to make changes to the subsystem after installation and
without rebooting.
This dynamic device recognition capability replaces the static methods of
device recognition that have been employed by using the compiled-in device
table, /sys/data/cam_data.c.
Note
SCSI devices in the /sys/data/cam_data.c file are supported for
this release of the operating system, but support will be
withdrawn in a future release.
The ddr.dbase file contains device specifications for the SCSI CAM devices.
To manage these devices, you edit the ddr.dbase file to contain new or
changed device information. After you have made changes to the ddr.dbase
file, you run the ddr_config utility, which compiles a new version of the
database, places the output in the /etc/ddr.db binary database file, and
notifies the kernel that the device database has changed. Subsequently,
the kernel synchronizes its in-memory device tables with the /etc/ddr.db
binary database file.
The ddr.dbase file is an ASCII file and it is shipped on the distribution
medium already populated with general syntax and entries for supported
devices and templates for other devices.
Semantics, element definition, and formats conform to the specifications of
SCSI-2, SMALL COMPUTER SYSTEM INTERFACE - 2 (X3.131-1994).
General Syntax Rules
The following list contains the general syntax rules for entries in the
ddr.dbase file:
· Comments: Text starting with the # character is a comment until the
end of the line.
· Whitespace: Leading and separating whitespace is ignored.
· Identifiers: Identifiers must be fully specified; are case
insensitive.
· Integers: Integers can be specified as decimal, hexadecimal (when
preceded with 0x), or octal (when preceded with 0).
· Tokens: All tokens are case insensitive. All tokens must be fully
specified, with the exception of Yes and No tokens, which are
recognized by the first letter only.
· Strings: Strings are case sensitive when enclosed by quotes.
Otherwise, strings are converted to lowercase.
Database Structure
There are three parts to the ddr.dbase file:
· A VERSION data section
· One or more GLOBAL data sections
· One or more SCSIDEVICE data sections
Each of these sections is identified by a keyword.
VERSION Data Section
The VERSION data section defines which version of the ddr.dbase syntax the
file conforms to. The syntax for the section keyword is:
VERSION = version
The first line in the ddr.dbase file that is not a comment line must
contain this version keyword and string.
GLOBAL Data Section
The GLOBAL data section contains information used by the device data
sections for two classes of attributes: disk partition sizes and tape
density settings.
The object of the global partition information is to allow the kernel to
create a default partition layout based on a disk's capacity and block
size. You specify global information in this data section to change the
defaults for disk devices.
The object of the global SCSI density code translation table for tapes is
to define the density values (bpi) and blocking factors for the SCSI
density codes that are obtained from tape devices.
You can use the strings defined in the density tables to specify SCSI
density codes to the subsequent SCSIDEVICE subsections of this file instead
of explicitly stating the integer values in the SCSIDEVICE subsections.
The GLOBAL data section syntax is as follows. The first data line in a
global data section contains the GLOBAL keyword. The lines following the
GLOBAL keyword line contain data lines. Each data line contains a single
data element. Excepting as noted in the following discussion, data lines
can be specified in any order, or omitted. The GLOBAL data section that
contains the SCSI density code translation table must precede all
SCSIDEVICE data section lines in the ddr.dbase file.
The PARTITION data line syntax is as follows.
· Each PARTITION data line consists of an identity equated to a value.
In the /ddr.dbase file for VERSION 1, there are four data lines and
they are:
Partition_A_size = 64
Partition_B_size = 128
Partition_G_size = 400
min_partition_size = 50
· If any of these values are not specified, they default to values
compiled into the system.
The density code translation table syntax is as follows.
· The first data line in a density code translation table must be the
specification for the size of the table, an identity equated to a
value.
· For VERSION 1, this data line must be:
scsi_density_table_size = 0x30
· There must be at least one subsequent entry in the table. These data
lines are specified as an identifier and density code equated to a
density name string, a bpi value, and a block size value (in bytes).
· The general format for these data lines is:
scsi_tape_density[density_code] = "name" bpi block_size
· The data lines can be specified in any order. If an element in a data
line is not specified, it is assigned a NULL value. A block_size of
zero indicates that the default blocking factor for the device is used
and variable-size record blocking is allowed.
SCSIDEVICE Data Section
The first data line in a SCSI device data section must contain the
SCSIDEVICE keyword. There must be a SCSIDEVICE data section for each
device to be defined in the ddr.dbase file.
The next two data lines are also required: they define the vendor,
product, and revision names that identify the device.
Type = type
Specifies one of the device types defined in the ddr.dbase file:
disk
tape
printer
processor
worm
rodirect
cdrom
scanner
optical
changer
comm
Name = vendor_id [product_id [revision]]
Specifies the SCSI vendor identification string, and optionally,
the SCSI product identification string and product version
string.
SCSIDEVICE Subsections
Each SCSI device data section is divided into subsections identified by the
following keywords:
PARAMETERS:
MODESELECT:
DENSITY:
ATTRIBUTE:
PARAMETERS: Subsection
Entries in this subsection specify the operational parameters for SCSI
devices. The syntax rules are:
The first line in the parameters section must contain the PARAMETERS:
keyword.
The lines following the PARAMETERS: keyword contain data lines. Each data
line contains a single data element. Data lines can be specified in any
order, or omitted. Data lines that are not specified inherit the values of
the default device entry for the device type.
TypeSubClass = class[,attribute]
Specifies a subclass of the device type. Valid only for disks
and tapes.
For disk devices, specify class as one of the following strings:
hard_disk
cdrom
floppy_3.5
floppy_5.25
Additionally, for disk devices, specify the attribute string raid
to indicate that the disk is functioning as a raid storage
device.
For tape devices, specify class as one of the following strings:
9trk
qic
8mm
3480
DLT
rdat
Additionally, for tape devices, specify the attribute string
loader to indicate that the tape unit also has an attached loader
that does not have a separate target id. That is, the tape unit
is at one lun on the target and the loader is at another lun on
the target.
BlockSize = integer
Physical record size of the device, in bytes.
MaxTransferSize = integer
Maximum transfer size allowed for the device, in bytes.
BadBlockRecovery = enabled | disabled
If the device supports bad block recovery, enable or disable the
feature. Valid only for disk devices.
SyncTransfers = enabled | disabled
If the device supports synchronous transfers, enable or disable
the feature.
WideTransfers = enabled | disabled
If the device supports wide transfers, enable or disable the
feature.
DynamicGeometry = true | false
The device has a configurable geometry (or capacity) that may
change during run time.
Disconnects = enabled | disabled
If the device supports SCSI bus disconnects, enable or disable
the feature.
CmdReordering = enabled | disabled
Allow the underlying SIM to reorder CCBs by enabling or disabling
the feature.
TaggedQueuing = enabled | disabled
If the device supports Tagged Queuing, enable or disable the
feature.
TagQueueDepth = integer
The number of simultaneously active tagged requests the device
supports. Range is 0 to 255.
WCE_Capable = true | false
The device is capable of running with its write-back cache
enabled. Valid for disk devices only.
PwrMgmt_Capable = true | false
The device is capable of being spun down and back up for power
management.
LongTimeoutRetry = enabled | disabled
Do select timeout retries.
ReadyTimeSeconds = integer
The time, in seconds, to delay between power on and device ready
states.
CMD_PreventAllow = supported | notsupported
The device supports the Prevent/Allow command (Opcode 0x1E).
CMD_ExtReserveRelease = supported | notsupported
The device supports the Reserve and Release commands (Opcodes
0x16 and 0x17).
CMD_WriteVerify = supported | notsupported
The device supports the write verify command (Opcode 0x2E).
[Note that use is limited to RAID devices, specifically the HSZ10
and HSZ15.]
DisperseQueue = true | false
The tagged request queue is to be distributed across all luns on
the device.
InquiryLength = integer
Size of Inquiry data buffer to allocate for device. Range is 0
to 255.
RequestSenseLength = integer
Size of Request Sense data buffer to allocate for device. Range
is 0 to 255.
MODESELECT: Subsection
Some devices require mode selects to be sent to a device the first time
that it is accessed so that the device can be placed in a known operational
state. The CAM subsystem supports up to eight mode selects to be sent to
the device.
The MODESELECT: subsection specifies the data for a single mode select.
Only the 6-byte mode select command, the mode select header, (optionally)
an 8-byte block descriptor, and a single page of data, is supported.
Up to eight mode select subsections can be specified for a device. The
order in which the mode selects are sent to the device is based on the
value of the ModeSelectNumber field (see below). Mode select number 0 will
be sent first, followed by 1, and so on. The mode select number for each
Mode Select subsection must be unique, and there must not be any holes (for
example, you cannot define mode select numbers 1 and 3 without defining
mode select number 2).
Each line in this subsection contains a single element of data.
The first line must contain the MODESELECT: keyword.
The following data lines must be specified, and must precede any optional
data lines specified. These data lines may be specified in any order.
ModeSelectNumber = integer
Specifies the relative position that this mode select is to be
issued to the device. Range is 0 to 7.
SavePage = Yes | No
The SP field (Byte 1 Bit 0) of the Mode Select Command.
Specifies if the Mode Select data is to be saved by the device.
PageFormat = scsi1 | scsi2
The PF field (Byte 1 Bit 4) of the Mode Select Command.
Identifies which Page format specification the mode select
conforms to.
BlockDescriptor = Yes | No
Specify Yes to send an 8-byte block descriptor. Specify No to
prevent an 8-byte block descriptor from being sent.
TransferLength = integer
The Parameter List Length field (byte 4) of the Mode Select
Command. Specifies the length of mode select data to be
transferred, in bytes. This value should include the size of the
Mode Parameter Header, Block Descriptor, and the Page Data.
Using this value, the subsystem calculates the Page Length entry
for the Page data. Range is 0 to 255.
The following data lines are optional. If an entry is not specified, the
device data inherits the value of zero for the entry. The data lines can
be specified in any order.
Hdr.MediumType = integer
The Medium Type field (Byte 1) of the Mode Parameter Header.
Range is 0 to 255.
Hdr.DeviceSpecific = integer
The Device-Specific Parameter field (Byte 2) of the Mode
Parameter Header. This identifier is to be used whenever the
device is not a tape or disk. Range is 0 to 255.
Hdr.Tape.Speed = integer
The Speed field (Byte 2 Bits 0-3) of the Mode Parameter Header.
Range is 0 to 15. Use this identifier only with tape devices.
Hdr.Tape.BufferMode = integer
The Buffered Mode field (Byte 2 Bits 4-6) of the Mode Parameter
Header. Range is 0 to 7. Use this identifier only with tape
devices.
BlkDescr.Density = integer | string
The Density Code field (Byte 0) of the Block Descriptor. Specify
this identifier only when the BlockDescriptor value is Yes. This
identifier is accepted if the device type is specified as tape,
cdrom, or optical. Range is 0 to 255. Note: for tape devices,
the actual strings and values that are accepted are in the GLOBAL
section, in the SCSI density code translation table.
The following string values are accepted for cdrom devices:
"default" => 0x00 = Default density.
"dataonly" => 0x01 = User data only.
2048 bytes per sector.
"dataaux" => 0x02 = User data, Aux data.
2336 bytes per sector.
"tagdataaux" => 0x03 = 4byte tag, User data, Aux
data. 2340 bytes per sector.
"audio" => 0x04 = Audio Information Only.
1/75th of a second per block.
The following string values are accepted for optical devices:
"default" => 0x00 = Default density
BlkDescr.NumberBlocks = integer
Specify this identifier only when the BlockDescriptor value is
Yes. The Number of Blocks field (Bytes 1-3) of the Block
Descriptor. Range is 0 to 16777215 (2^24 - 1).
BlkDescr.Reserved = integer
Specify this identifier only when the BlockDescriptor value is
Yes. The Reserved field (Byte 4) of the Block Descriptor. Range
is 0 to 255.
BlkDescr.BlockLength = integer
Specify this identifier only when the BlockDescriptor value is
Yes. The Block Length field (Bytes 5-7) of the Block Descriptor.
Range is 0 to 16777215 (2^24 - 1).
Data.UBYTE[index] = integer
Used to set a byte quantity within the Page Data. Range for
index is 0 to (<TransferLength> - 11). Range for integer is 0 to
255.
Data.USHORT[index] = integer
Used to set a short quantity within the Page Data. Range for
index is 0 to ((<TransferLength> - 11)/2). Range for integer is
0 to 65535.
Data.UINT[index] = integer
Used to set an int quantity within the Page Data. Range for
index is 0 to ((<TransferLength> - 11)/4). Range for integer is
0 to (2^32 - 1).
Data.ULONG[index] = integer
Used to set a long quantity within the Page Data. Range for
index is 0 to ((<TransferLength> - 11)/8). Range for integer is
0 to (2^64 - 1).
DENSITY: Subsection
The CAM subsystem support for tape devices allows specific densities
(including the enabling of compression, and so on), to be selected when
accessing the tape.
Note
When reading a tape, the device may override the density selected
by autoselecting a density based on the media present
The densities are selected based on the bits 1-3 of the minor device number
for the tape device (/dev) node (bit 0 being the rewind/no-rewind
indicator). Thus, eight different densities may be selected.
Currently, device nodes are made for only 4 of the 8 possible density
values (0-3), which are reflected in the device node name by the suffixes
(low), h (high), m (medium), and a (alternate) respectively.
This subsection specifies the density information that is sent to the
device via a mode select (with the Device Configuration Page) in order to
set the tape density. The assignment of density to minor bit values done
via the DensityNumber field (see below). Up to eight density subsections
may be specified for one device.
Each line within this subsection contains a single element of data.
The first data line in the density subsection must contain the DENSITY:
keyword.
After the DENSITY: data line, the The following data line must be
specified, and must precede any optional data lines
DensityNumber = integer [, integer ,...]
Specifies the density bit values in the minor device number that
this density subsection corresponds to. The values for this
density subsection may apply to multiple minor device numbers by
specifying each applicable number in a comma separated list.
Range for integer is 0 to 7.
The following data lines are optional. If a data line is not specified,
the device data inherits the value of zero for the entry. The data lines
can be specified in any order.
OneFileMarkOnClose = Yes | No
Specify Yes to write only one file mark when closing the device.
Specify no to write two file marks when closing the device.
Speed = integer
The Speed field (Byte 2 Bits 0-3) of Mode Parameter Header sent
to the device. Range is 0 to 15.
Buffered = integer
The Buffered Mode field (Byte 2 Bits 4-6) of the Mode Parameter
Header sent to the device. Range is 0 to 7.
DensityCode = integer | densitystring
The Density Code field (Byte 0) of the Block Descriptor sent to
the device. Range of integer is 0 to 255. The strings from the
global section density table (tape only) are valid here for
densitystring.
Blocking = integer
The Number of Blocks field (Bytes 1-3) of the Block Descriptor
that is sent to the device. A NULL value (zero) means variable
size. Range is 0 to 16777215 (2^24 - 1).
CompressionCode = integer
The Select Data Compression Algorithm field (Byte 14) of the Page
data for Page Code 0x10 (Device Configuration Page). Range is 0
to 255.
ATTRIBUTE: Subsection
The CAM subsystem now allows for device-specific attributes to be specified
for a device. These attributes are not used by the CAM subsystem; they are
provided as vendor-specific hooks for third party drivers.
This subsection specifies data for a single attribute. Any number of
attribute subsections may be specified for a device.
Each line within this subsection contains a single element of data.
The first line of data in the attribute subsection must include the
ATTRIBUTE: keyword.
After the ATTRIBUTE: keyword is specified, The following data lines must be
specified, and must precede any optional data lines specified. These data
lines may be specified in any order.
Name = string
A string specifying the name of the attribute. Strings are case
sensitive when enclosed by quotes. Otherwise, strings are
converted to lowercase.
Length = integer
The length, in bytes, of the attribute data.
The following data lines are optional. If an entry is not specified, the
attribute data inherits the value of zero for the entry. The data lines
can be specified in any order.
UBYTE[index] = integer
Used to set a byte quantity within the attribute data. Range for
index is 0 to (<Length> - 1). Range for integer is 0 to 255.
USHORT[index] = integer
Used to set a short quantity within the attribute data. Range
for index is 0 to ((<Length> - 1)/2). Range for integer is 0 to
65535.
UINT[index] = integer
Used to set a int quantity within the attribute data. Range for
index is 0 to ((<Length> - 1)/4). Range for integer is 0 to
(2^32 - 1).
ULONG[index] = integer
Used to set a long quantity within the attribute data. Range for
index is 0 to ((<Length> - 1)/8). Range for integer is 0 to
(2^64 - 1).
STRING = string
Used to set the contents of the attribute data to the contents of
a text string. The length of the string must be no longer than
(<Length> - 1). Any attribute data beyond the end of the string
will be set to zero. Strings are case sensitive when enclosed in
quotes. Otherwise, strings are converted to lowercase. [Note:
the string contained in the attribute data will always be null-
terminated).
EXAMPLES
See the /etc/ddr.dbase file for examples of use.
FILES
/etc/ddr.db
The binary database file of SCSI device definitions
/sbin/ddr_config The utility that compiles the /etc/ddr.dbase
file into the
/etc/ddr.db file
RELATED INFORMATION
Commands: ddr_config(8)
Hardware Management
Files: disktab(4).
SCSI-2, SMALL COMPUTER SYSTEM INTERFACE - 2 (X3.131-1994)
|
Index for
Section 4 |
|
|
Alphabetical
listing for D |
|
 |
Top of
page |
|