[PATCH AUTOSEL 4.4 6/6] scsi: hpsa: correct ioaccel2 chaining

[Sasha Levin]

From: Don Brace <don.brace@xxxxxxxxxxxxx>

[ Upstream commit 625d7d3518875c4d303c652a198feaa13d9f52d9 ]

- set ioaccel2_sg_element member 'chain_indicator' to IOACCEL2_LAST_SG for
  the last s/g element.

- set ioaccel2_sg_element member 'chain_indicator' to IOACCEL2_CHAIN when
  chaining.

Reviewed-by: Bader Ali - Saleh <bader.alisaleh@xxxxxxxxxxxxx>
Reviewed-by: Scott Teel <scott.teel@xxxxxxxxxxxxx>
Reviewed-by: Matt Perricone <matt.perricone@xxxxxxxxxxxxx>
Signed-off-by: Don Brace <don.brace@xxxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/scsi/hpsa.c     | 7 ++++++-
 drivers/scsi/hpsa_cmd.h | 1 +
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index 910b795fc5eb..e0952882e132 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -4562,7 +4562,7 @@ static int hpsa_scsi_ioaccel2_queue_command(struct ctlr_info *h,
 			curr_sg->reserved[0] = 0;
 			curr_sg->reserved[1] = 0;
 			curr_sg->reserved[2] = 0;
-			curr_sg->chain_indicator = 0x80;
+			curr_sg->chain_indicator = IOACCEL2_CHAIN;
 
 			curr_sg = h->ioaccel2_cmd_sg_list[c->cmdindex];
 		}
@@ -4579,6 +4579,11 @@ static int hpsa_scsi_ioaccel2_queue_command(struct ctlr_info *h,
 			curr_sg++;
 		}
 
+		/*
+		 * Set the last s/g element bit
+		 */
+		(curr_sg - 1)->chain_indicator = IOACCEL2_LAST_SG;
+
 		switch (cmd->sc_data_direction) {
 		case DMA_TO_DEVICE:
 			cp->direction &= ~IOACCEL2_DIRECTION_MASK;
diff --git a/drivers/scsi/hpsa_cmd.h b/drivers/scsi/hpsa_cmd.h
index 26488e2a7f02..7ffde12d57d4 100644
--- a/drivers/scsi/hpsa_cmd.h
+++ b/drivers/scsi/hpsa_cmd.h
@@ -513,6 +513,7 @@ struct ioaccel2_sg_element {
 	u8 reserved[3];
 	u8 chain_indicator;
 #define IOACCEL2_CHAIN 0x80
+#define IOACCEL2_LAST_SG 0x40
 };
 
 /*
-- 
2.20.1