NAME

xy − Disk driver for Xylogics SMD Disk Controllers

SYNOPSIS — SUN-3

controller xyc0 at vme16d16 ? csr 0xee40 priority 2 vector xyintr 72
controller xyc1 at vme16d16 ? csr 0xee48 priority 2 vector xyintr 73
disk xy0 at xyc0 drive 0
disk xy1 at xyc0 drive 1
disk xy2 at xyc1 drive 0
disk xy3 at xyc1 drive 1

The two controller lines given in the synopsis sections above specify the first and second Xylogics 450 SMD disk controller in a Sun system. 

SYNOPSIS — SUN-2

controller xyc0 at vme16 ? csr 0xee40 priority 2 vector xyintr 72
controller xyc1 at vme16 ? csr 0xee48 priority 2 vector xyintr 73
controller xyc0 at mbio ? csr 0xee40 priority 2
controller xyc1 at mbio ? csr 0xee48 priority 2
disk xy0 at xyc0 drive 0
disk xy1 at xyc0 drive 1
disk xy2 at xyc1 drive 0
disk xy3 at xyc1 drive 1

The first two controller lines specify the first and second Xylogics 450 SMD disk controllers in a Sun-2/160 VMEbus based system.  The third and fourth controller lines specify the first and second Xylogics 450 SMD disk controllers in a Sun-2/120 or a SUn-2/170 Multibus based system. 

DESCRIPTION

Files with minor device numbers 0 through 7 refer to various portions of drive 0; minor devices 8 through 15 refer to drive 1, and so on.  The standard device names begin with ‘xy’ 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 via 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 usually results in only one I/O operation; 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. 

DISK SUPPORT

This driver handles all SMD drives by reading a label from sector 0 of the drive which describes the disk geometry and partitioning. 

The xy?a partition is normally used for the root file system on a disk, the xy?b partition as a paging area, and the xy?c partition for pack-pack copying (it normally maps the entire disk).  The rest of the disk is normally the xy?g partition. 

FILES

/dev/xy[0-7][a-h]block files
/dev/rxy[0-7][a-h]raw files

SEE ALSO

dkio(4S)
Xylogics Model 450 Peripheral Processor SMD Disk Subsystem Maintenance and Reference Manual (Sun 800-1025-01)

DIAGNOSTICS

xyc%d: self test error %x - %s.  Self test error in controller, see the Maintenance and Reference Manual. 

xyc%d: address mode jumper is wrong.  The controller is strapped for 24-bit Multibus addresses.  Sun systems use 20-bit addresses for Multibus based systems and 24-bit addresses for VMEbus based systems.  See the subsection on the Xylogics controller in the appropriate Sun Hardware Installation Manual for your machine(s) for instructions on how to set the jumpers on the 450. 

xyattach: can’t get bad sector info.  The bad sector forwarding information for the disk, which is kept on the last cylinder, could not be read. 

xy%d: drive type %d clash with xy%d.  The 450 does not support mixing the drive types found on these units on a single controller. 

xy%d: initialization failed. 

xy%d: error %x reading label on head %d.  Error reading drive geometry/partition table information. 

xy%d: Corrupt label.  The geometry/partition label checksum was incorrect. 

xy%d: Unsupported phys partition # %d. 

xy%d: offline. 

xy%d%c: cmd how (msg) blk %d.  A command such as read, write, or format encountered a error condition (how): either it failed, the unit was restored, or an operation was retry’ed.  The msg is derived from the error number given by the controller, indicating a condition such as ‘drive not ready’, ‘sector not found’ or ‘disk write protected’. 

BUGS

In raw I/O read and write(2) truncate file offsets to 512-byte block boundaries, and write scribbles on the tail of incomplete blocks.  Thus, in programs that are likely to access raw devices, read, write and lseek(2) should always deal in 512-byte multiples.

Sun Release 3.0β  —  Last change: 16 September 1985