From: Mike Christie <michael.christie@oracle.com>

This has target_core_iblock use the LIO helper function to translate its
block_device atomic settings to LIO settings. If we then get a write
that LIO has indicated is atomic via the SCF_ATOMIC flag, we use the
REQ_ATOMIC flag to tell the block layer to perform an atomic write.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: John Garry <john.g.garry@oracle.com>
---
 drivers/target/target_core_iblock.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 281612b9830f8..8ec7b534ad760 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -152,6 +152,8 @@ static int iblock_configure_device(struct se_device *dev)
 	if (bdev_nonrot(bd))
 		dev->dev_attrib.is_nonrot = 1;
 
+	target_configure_write_atomic_from_bdev(&dev->dev_attrib, bd);
+
 	bi = bdev_get_integrity(bd);
 	if (!bi)
 		return 0;
@@ -773,6 +775,9 @@ iblock_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 			else if (!bdev_write_cache(ib_dev->ibd_bd))
 				opf |= REQ_FUA;
 		}
+
+		if (cmd->se_cmd_flags & SCF_ATOMIC)
+			opf |= REQ_ATOMIC;
 	} else {
 		opf = REQ_OP_READ;
 		miter_dir = SG_MITER_FROM_SG;
-- 
2.43.5