tree 7aa9e70ef2432d702ada2fac12026de8bfb35405
parent edced191e4512b7795380563634f4d44b21c684a
author Michael Reed <mdr@sgi.com> 1249923568 -0500
committer James Bottomley <James.Bottomley@suse.de> 1250981542 -0500

[SCSI] reservation conflict after timeout causes device to be taken offline

An IBM tape drive failed to complete a PERSISTENT RESERVE IN within the scsi
cmd timeout.  Error recovery was initiated and it sequenced from abort through
taking the tape drive offline.

The device was taken offline because it repeatedly responded to the TUR command
issued by error recovery with a RESERVATION CONFLICT status.  The tape drive
was reserved to another system.  This is perfectly legitimate response to TUR,
and is one that an escalation of recovery is unlikely to clear.  Further,
escalation of recovery can have undesirable side effects on the operation of
tape drives shared with other initiators.

Instead of escalating recovery, error recovery should treat the RESERVATION
CONFLICT response to the TUR as a good status, giving the issuer of the
command the opportunity to handle the timeout and reservation conflict.

Signed-off-by: Michael reed <mdr@sgi.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>