From a611e794730ea46bc43c4f76f7940620fa5dba83 Mon Sep 17 00:00:00 2001
From: Damien Le Moal <damien.lemoal@wdc.com>
Date: Thu, 12 Jan 2017 15:25:10 +0900
Subject: [PATCH] scsi: sd: Fix wrong DPOFUA disable in sd_read_cache_type

BugLink: http://bugs.launchpad.net/bugs/1702863

[ Upstream commit 26f2819772af891dee2843e1f8662c58e5129d5f ]

Zoned block devices force the use of READ/WRITE(16) commands by setting
sdkp->use_16_for_rw and clearing sdkp->use_10_for_rw. This result in
DPOFUA always being disabled for these drives as the assumed use of
the deprecated READ/WRITE(6) commands only looks at sdkp->use_10_for_rw.
Strenghten the test by also checking that sdkp->use_16_for_rw is false.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
---
 drivers/scsi/sd.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 4d5207dff960..8750c86f95f9 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -2566,7 +2566,8 @@ sd_read_cache_type(struct scsi_disk *sdkp, unsigned char *buffer)
 		if (sdp->broken_fua) {
 			sd_first_printk(KERN_NOTICE, sdkp, "Disabling FUA\n");
 			sdkp->DPOFUA = 0;
-		} else if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw) {
+		} else if (sdkp->DPOFUA && !sdkp->device->use_10_for_rw &&
+			   !sdkp->device->use_16_for_rw) {
 			sd_first_printk(KERN_NOTICE, sdkp,
 				  "Uses READ/WRITE(6), disabling FUA\n");
 			sdkp->DPOFUA = 0;
-- 
2.30.9