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@(#)hk.4 6.3 (Berkeley) 06/13/88

C 4 hk - RK6-11/RK06 and RK07 moving head disk "controller hk0 at uba? csr 0177440 vector rkintr"

"disk rk0 at hk0 drive 0"

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 ``hk'' 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 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 origin and size (in sectors) of the pseudo-disks on each drive are as follows:

RK07 partitions:
 disk start length cyl
 hk?a 0 15884 0-240
 hk?b 15906 10032 241-392
 hk?c 0 53790 0-814
 hk?d 25938 15884 393-633
 hk?f 41844 11792 634-814
 hk?g 25938 27786 393-813

RK06 partitions
 disk start length cyl
 hk?a 0 15884 0-240
 hk?b 15906 11154 241-409
 hk?c 0 27126 0-410

On a dual RK-07 system partition hk?a is used for the root for one drive and partition hk?g for the /usr file system. If large jobs are to be run using hk?b on both drives as swap area provides a 10Mbyte paging area. Otherwise partition hk?c on the other drive is used as a single large file system.

/dev/hk[0-7][a-h] block files

/dev/rhk[0-7][a-h] raw files

hp(4), uda(4), up(4), syslogd(8) hk%d%c: hard error %sing fsbn %d[-%d] cs2=%b ds=%b er=%b. An unrecoverable error occurred during transfer of the specified filesystem block number(s), which are logical block numbers on the indicated partition. The contents of the cs2, ds and er registers are printed in octal and symbolically with bits decoded. The error was either unrecoverable, or a large number of retry attempts (including offset positioning and drive recalibration) could not recover the error.

rk%d: write locked. The write protect switch was set on the drive when a write was attempted. The write operation is not recoverable.

rk%d: not ready. The drive was spun down or off line when it was accessed. The i/o operation is not recoverable.

rk%d: not ready (came back!). The drive was not ready, but after printing the message about being not ready (which takes a fraction of a second) was ready. The operation is recovered if no further errors occur.

up%d%c: soft ecc reading fsbn %d[-%d]. A recoverable ECC error occurred on the specified sector(s) in the specified disk partition. This happens normally a few times a week. If it happens more frequently than this the sectors where the errors are occurring should be checked to see if certain cylinders on the pack, spots on the carriage of the drive or heads are indicated.

hk%d: lost interrupt. A timer watching the controller detected no interrupt for an extended period while an operation was outstanding. This indicates a hardware or software failure. There is currently a hardware/software problem with spinning down drives while they are being accessed which causes this error to occur. The error causes a UNIBUS reset, and retry of the pending operations. If the controller continues to lose interrupts, this error will recur a few seconds later.

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.

DEC-standard error logging should be supported.

A program to analyze the logged error information (even in its present reduced form) is needed.

The partition tables for the file systems should be read off of each pack, as they are never quite what any single installation would prefer, and this would make packs more portable.

The rk07 g partition size in rk.c disagrees with that in /etc/disktab.