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

[Shaohua Li]

For io.low, latency target 0 is legit. 0 for rbps/wbps/rios/wios is ok
too. And we use 0 to clear io.low settings.

Cc: Tejun Heo <t...@kernel.org>
Signed-off-by: Shaohua Li <s...@fb.com>
---
 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 96ad326..7040285 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -1633,7 +1633,7 @@ 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