[PATCH] blk-throttle: allow configure 0 for some settings

[Shaohua Li <shli@xxxxxx>]

For io.low, latency target 0 is legit. 0 for rbps/wbps/rios/wios is ok
too as long as not all of them are 0.

Signed-off-by: Shaohua Li <shli@xxxxxx>
---
 block/blk-throttle.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 0fea76a..ee6d7b0 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -1632,7 +1632,7 @@ static ssize_t tg_set_limit(struct kernfs_open_file *of,
 			goto out_finish;
 
 		ret = -ERANGE;
-		if (!val)
+		if (!val && off != LIMIT_LOW)
 			goto out_finish;
 
 		ret = -EINVAL;
-- 
2.9.5