svn commit: r332458 - head/sys/cam/scsi

[Kenneth D. Merry]

Author: ken
Date: Thu Apr 12 21:21:18 2018
New Revision: 332458
URL: https://svnweb.freebsd.org/changeset/base/332458

Log:
  Handle Programmable Early Warning for control commands in sa(4).
  
  When the tape position is inside the Early Warning area, the tape
  drive will return a sense key of NO SENSE, and an ASC/ASCQ of
  0x00,0x02, which means: End-of-partition/medium detected".  If
  this was in response to a control command like WRITE FILEMARKS,
  we correctly translate this as informational status and return
  0 from saerror().
  
  Programmable Early Warning should be handled the same way, but
  we weren't handling it that way.  As a result, if a PEW status
  (sense key of NO SENSE, ASC/ASCQ of 0x00,0x07, "Programmable early
  warning detected") came back in response to a WRITE FILEMARKS,
  we returned an error.
  
  The impact of this was that if an application was writing to a
  sa(4) device, and a PEW area was set (in the Device Configuration
  Extension subpage -- mode page 0x10, subpage 1), and a filemark
  needed to be written on close, we could wind up returning an error
  to the user on close because of a "failure" to write the filemarks.
  
  It actually isn't a failure, but rather just a status report from
  the drive, and shouldn't be treated as a failure.
  
  sys/cam/scsi/scsi_sa.c:
  	For control commands in saerror(), treat asc/ascq 0x00,0x07
  	the same as 0x00,{0-5} -- not an error.  Return 0, since
  	the command actually did succeed.
  
  Reported by:	Dr. Andreas Haakh <andreas at haakh.de>
  Tested by:	Dr. Andreas Haakh <andreas at haakh.de>
  Sponsored by:	Spectra Logic
  MFC after:	3 days

Modified:
  head/sys/cam/scsi/scsi_sa.c

Modified: head/sys/cam/scsi/scsi_sa.c
==============================================================================
--- head/sys/cam/scsi/scsi_sa.c	Thu Apr 12 21:13:30 2018	(r332457)
+++ head/sys/cam/scsi/scsi_sa.c	Thu Apr 12 21:21:18 2018	(r332458)
@@ -3453,12 +3453,13 @@ saerror(union ccb *ccb, u_int32_t cflgs, u_int32_t sfl
 			break;
 		}
 		/*
-		 * If this was just EOM/EOP, Filemark, Setmark or ILI detected
-		 * on a non read/write command, we assume it's not an error
-		 * and propagate the residule and return.
+		 * If this was just EOM/EOP, Filemark, Setmark, ILI or
+		 * PEW detected on a non read/write command, we assume
+		 * it's not an error and propagate the residual and return.
 		 */
-		if ((aqvalid && asc == 0 && ascq > 0 && ascq <= 5) ||
-		    (aqvalid == 0 && sense_key == SSD_KEY_NO_SENSE)) {
+		if ((aqvalid && asc == 0 && ((ascq > 0 && ascq <= 5)
+		  || (ascq == 0x07)))
+		 || (aqvalid == 0 && sense_key == SSD_KEY_NO_SENSE)) {
 			csio->resid = resid;
 			QFRLS(ccb);
 			return (0);