This issue is specific to SLI-3 adapters, specifically when DIF is used.

Once seen, this message floods the logs:
9064 BLKGRD: lpfc_scsi_prep_dma_buf_s3: Too many sg segments from
  dma_map_sg

The driver, upon detecting an error such as too many elements in an sglist,
misrepresents the error by treating it as a temporary resource issue by
returning MLQUEUE_HOST_BUSY.  In these cases, no retry will fix it and it
should have been a hard error. The repeated retry was causing the spamming
of the log.

As for the initial reason of why an I/O encountered this issue at all is
not clear as parameters set by the driver should have avoided this.  The
dm multipath maintainer has been notified of the issue.

Fix by changing the return code for the dma mapping routines to indicate
cases that are not retryable and return DID_ERROR on those cases.
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>