[PATCH] dax: fix mapping_store() returning 0 instead of error code

[jianyungao89]

From: Jianyun Gao <jianyungao89@xxxxxxxxx>

When the region driver is not loaded, mapping_store() returns rc
which is 0 at that point, instead of an error code. Set it to
-ENXIO to match the equivalent check in size_store().

Fixes: 9567da0b408a ("device-dax: Introduce bus + driver model")
Signed-off-by: Jianyun Gao <jianyungao89@xxxxxxxxx>
---
 drivers/dax/bus.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
index b809e1a264af..262f97b5e7aa 100644
--- a/drivers/dax/bus.c
+++ b/drivers/dax/bus.c
@@ -1192,7 +1192,7 @@ static ssize_t mapping_store(struct device *dev, struct device_attribute *attr,
 		return rc;
 	if (!dax_region->dev->driver) {
 		up_write(&dax_region_rwsem);
-		return rc;
+		return -ENXIO;
 	}
 	rc = down_write_killable(&dax_dev_rwsem);
 	if (rc) {
-- 
2.34.1