4.14-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx>
[ Upstream commit 89d0c804392bb962553f23dc4c119d11b6bd1675 ]
iscsi tcp will first send out data, then calculate and send data
digest. If we don't have BDI_CAP_STABLE_WRITES, the page cache will be
written in spite of the on going writeback. Consequently, wrong digest
will be got and sent to target.
To fix this, set BDI_CAP_STABLE_WRITES when data digest is enabled
in iscsi_tcp .slave_configure callback.
Signed-off-by: Jianchao Wang <jianchao.w.wang@xxxxxxxxxx>
Acked-by: Chris Leech <cleech@xxxxxxxxxx>
Acked-by: Lee Duncan <lduncan@xxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/scsi/iscsi_tcp.c | 8 ++++++++
1 file changed, 8 insertions(+)
--- a/drivers/scsi/iscsi_tcp.c
+++ b/drivers/scsi/iscsi_tcp.c
@@ -37,6 +37,7 @@
#include <linux/kfifo.h>
#include <linux/scatterlist.h>
#include <linux/module.h>
+#include <linux/backing-dev.h>
#include <net/tcp.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
@@ -952,6 +953,13 @@ static int iscsi_sw_tcp_slave_alloc(stru
static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev)
{
+ struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(sdev->host);
+ struct iscsi_session *session = tcp_sw_host->session;
+ struct iscsi_conn *conn = session->leadconn;
+
+ if (conn->datadgst_en)
+ sdev->request_queue->backing_dev_info->capabilities
+ |= BDI_CAP_STABLE_WRITES;
blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
blk_queue_dma_alignment(sdev->request_queue, 0);
return 0;
