NAME

dsd − st-506 disk/tape/floppy controller

SYNOPSIS

controller dsd0 at mb0 csr 0x7F00 priority 1 vector dsdintr
disk md0 at dsd0 drive 1 flags 0x00
disk md1 at dsd0 drive 2 flags 0x00

DESCRIPTION

This is a MULTIBUS st-506 disk and tape controller.  The driver software supports two winchester hard disk drives, one qic-02 streaming tape drive, and one floppy drive.  This manual page documents the hard disk support.  See qic for information on the streaming tape support and floppy for the floppy support. 

Files with minor device numbers 0 through 7 refer to various portions of drive 0; minor devices 8 through 15 refer to drive 1, etc.  The standard device names begin with “md” followed by the drive number and then a letter a-h for partitions 0-7 respectively.  The character ? stands here for a drive number in the range 0-7. 

The block files access the disk using the system’s normal buffering mechanism and may be read and written without regard to physical disk records.  There is also a ‘raw’ interface which provides for direct transmission between the disk and the user’s read or write buffer.  A single read or write call results in exactly one I/O operation and therefore raw I/O is considerably more efficient when many words are transmitted.  The names of the raw files conventionally begin with an extra ‘r.’

In raw I/O counts should be a multiple of 512 bytes (a disk sector).  Likewise seek calls should specify a multiple of 512 bytes. 

The size of the various partitions supported by the driver in fact are a function of the drive itself.  Present on each drive is a boot label which contains the partitions sizes and locations. 

FILES

/dev/md[01][a-h] block files
/dev/rmd[01][a-h] raw files

SEE ALSO

autoconf(7), qic(7), floppy(7)

DIAGNOSTICS

panic: dsdattach: geteblk() failed.  Can’t happen. See a guru. 
md%d (***No label***).  The named drive has no boot label and thus cannot be used. 
(%s Name: %s).  On a successful attach, the drive type is printed out followed by its “name” (a user specifiable name). 
md%d%c: %s err(%s) at %d/%d/%d retry:%d
%d/%d/%d req%d atc%d. A hard error of some sort occured. 
dsdcmd: dsdbusy was not set to Zero(0)
panic: dsd: no status posted
dsd: cmd(%s), dev(%d), controller is hung on the bus
panic: dsd: couldn’t start!
dsd: interrupt with empty queue
dsd: zero status
panic: dsdstatus
dsdstatus: dsdcmd failure
dsd: soft error: dev(%x). Any of the above errors indicates that something is seriously wrong with the controller. 

BUGS

There are far too many printouts in the driver. There should be specific messages for specific problems. 

Version 2.5  —  April 22, 1987