diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 10430d500792..393f9db8f41b 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -867,6 +867,17 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) /* for passthrough error may be set */ error = BLK_STS_OK; } + /* + * Another corner case: the SCSI status byte is non-zero but 'good'. + * Example: PRE-FETCH command returns SAM_STAT_CONDITION_MET when + * it is able to fit nominated LBs in its cache (and SAM_STAT_GOOD + * if it can't fit). Treat SAM_STAT_CONDITION_MET and the related + * intermediate statuses (both obsolete in SAM-4) as good. + */ + if (status_byte(result) && scsi_status_is_good(result)) { + result = 0; + error = BLK_STS_OK; + } /* * special case: failed zero length commands always need to diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h index cb85eddb47ea..eb7853c1a23b 100644 --- a/include/scsi/scsi.h +++ b/include/scsi/scsi.h @@ -47,6 +47,8 @@ static inline int scsi_status_is_good(int status) */ status &= 0xfe; return ((status == SAM_STAT_GOOD) || + (status == SAM_STAT_CONDITION_MET) || + /* Next two "intermediate" statuses are obsolete in SAM-4 */ (status == SAM_STAT_INTERMEDIATE) || (status == SAM_STAT_INTERMEDIATE_CONDITION_MET) || /* FIXME: this is obsolete in SAM-3 */