[PATCH] zram: move backing_dev under macro CONFIG_ZRAM_WRITEBACK

[Yue Hu]

From: Yue Hu <huyue2@xxxxxxxxxx>

backing_dev is never used when not enable CONFIG_ZRAM_WRITEBACK and
it's introduced from writeback feature. So it's needless also affect
readability in that case.

Signed-off-by: Yue Hu <huyue2@xxxxxxxxxx>
---
 drivers/block/zram/zram_drv.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
index f2fd46d..1cb3b9a 100644
--- a/drivers/block/zram/zram_drv.h
+++ b/drivers/block/zram/zram_drv.h
@@ -112,8 +112,8 @@ struct zram {
 	 * zram is claimed so open request will be failed
 	 */
 	bool claim; /* Protected by bdev->bd_mutex */
-	struct file *backing_dev;
 #ifdef CONFIG_ZRAM_WRITEBACK
+	struct file *backing_dev;
 	spinlock_t wb_limit_lock;
 	bool wb_limit_enable;
 	u64 bd_wb_limit;
-- 
1.9.1