Open issues from January 11 SAM working group

Charles Monia, SHR3-2/W4, 237-6757, monia@starch.enet.dec.com 08-Feb-1994 1847 monia at starch.enet.dec.com
Tue Feb 8 15:46:52 PST 1994


From:	Charles Monia
	SAM Technical Editor

To:	Members of X3T10

Subject: Open issues from January 11 SAM working group

Ref: (a) X3T10/94-043R0 Results of 11 January, 1994 SAM Working Group Review


The purpose of this note is to request feedback on the following open
issues from the last SAM working group review:

1) Logical unit policy for automatic return of sense data.

2) Logical unit response to a CLEAR ACA task management function
   while an ACA command is pending.


Item 1: When must a target automatically return sense data?

Assuming the protocol supports automatic return of sense data by a
target (AKA 'autosense'), and the application client (i.e., the device
driver) requests autosense information, when must the target return such
information?

a) If and only if a command terminates with a CHECK CONDITION or COMMAND
   TERMINATED status.

b) Any time sense data is available after completion of a command,
   regardless of status. E.g., on the occurrence of a recovered error
   after a status of GOOD was returned.

I have no bias either way. However, I should mention that if the protocol
does not support autosense, the behavior of alternative (a) can be
easily simulated by host software (e.g., the CAM-SIM layer).
Alternative B, on the other hand, cannot be simulated when sense data is
unexpectedly generated by the logical unit.


Item 2: After a contingent allegiance condition occurs, how should a
	logical unit respond to a CLEAR ACA task management function
	while an ACA command is pending?


Alternative a)	The CLEAR ACA task management function shall cause the
		ACA command to be aborted.

Alternative b)	The CLEAR ACA task management function shall not affect
		the pending ACA command. However, other pending commands
		may then complete.


Thanks,
Charles





More information about the T10 mailing list