[PATCH AUTOSEL 4.9 24/99] scsi: dc395x: fix DMA API usage in sg_update_list

From: Sasha Levin
Date: Sat Nov 16 2019 - 11:04:36 EST


From: Christoph Hellwig <hch@xxxxxx>

[ Upstream commit 6c404a68bf83b4135a8a9aa1c388ebdf98e8ba7f ]

We need to transfer device ownership to the CPU before we can manipulate
the mapped data.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/scsi/dc395x.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/scsi/dc395x.c b/drivers/scsi/dc395x.c
index 9da0ac360848f..830b2d2dcf206 100644
--- a/drivers/scsi/dc395x.c
+++ b/drivers/scsi/dc395x.c
@@ -1972,6 +1972,11 @@ static void sg_update_list(struct ScsiReqBlk *srb, u32 left)
xferred -= psge->length;
} else {
/* Partial SG entry done */
+ pci_dma_sync_single_for_cpu(srb->dcb->
+ acb->dev,
+ srb->sg_bus_addr,
+ SEGMENTX_LEN,
+ PCI_DMA_TODEVICE);
psge->length -= xferred;
psge->address += xferred;
srb->sg_index = idx;
--
2.20.1