[PATCH 5.19 0805/1157] scsi: smartpqi: Fix DMA direction for RAID requests

Greg Kroah-Hartman
2022-08-16T04:45:06Z

From: Mahesh Rajashekhara <Mahesh.Rajashekhara@microchip.com>

[ Upstream commit 69695aeaa6621bc49cdd7a8e5a8d1042461e496e ]

Correct a SOP READ and WRITE DMA flags for some requests.

This update corrects DMA direction issues with SCSI commands removed from
the controller's internal lookup table.

Currently, SCSI READ BLOCK LIMITS (0x5) was removed from the controller
lookup table and exposed a DMA direction flag issue.

SCSI READ BLOCK LIMITS was recently removed from our controller lookup
table so the controller uses the respective IU flag field to set the DMA
data direction. Since the DMA direction is incorrect the FW never completes
the request causing a hang.

Some SCSI commands which use SCSI READ BLOCK LIMITS

* sg_map
* mt -f /dev/stX status

After updating controller firmware, users may notice their tape units
failing. This patch resolves the issue.

Also, the AIO path DMA direction is correct.

The DMA direction flag is a day-one bug with no reported BZ.

Fixes: 6c223761eb54 ("smartpqi: initial commit of Microsemi smartpqi driver")
Link: https://lore.kernel.org/r/165730605618.177165.9054223644512926624.stgit@brunhilda
Reviewed-by: Scott Benesh <scott.benesh@microchip.com>
Reviewed-by: Scott Teel <scott.teel@microchip.com>
Reviewed-by: Mike McGowen <mike.mcgowen@microchip.com>
Reviewed-by: Kevin Barnett <kevin.barnett@microchip.com>
Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@microchip.com>
Signed-off-by: Don Brace <don.brace@microchip.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/smartpqi/smartpqi_init.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/smartpqi/smartpqi_init.c b/drivers/scsi/smartpqi/smartpqi_init.c
index 7c0d069a3158..e1fc6f5b9612 100644
--- a/drivers/scsi/smartpqi/smartpqi_init.c
+++ b/drivers/scsi/smartpqi/smartpqi_init.c
@@ -5484,10 +5484,10 @@ static int pqi_raid_submit_scsi_cmd_with_io_request(
}

switch (scmd->sc_data_direction) {
- case DMA_TO_DEVICE:
+ case DMA_FROM_DEVICE:
request->data_direction = SOP_READ_FLAG;
break;
- case DMA_FROM_DEVICE:
+ case DMA_TO_DEVICE:
request->data_direction = SOP_WRITE_FLAG;
break;
case DMA_NONE:
--
2.35.1