block: sysfs store function needs to grab queue_lock and use queue_flag_*()

Concurrency isn't a big deal here since we have requests in flight
at this point, but do the locked variant to set a better example.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index e85c4013e8a..304ec73ab82 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -146,11 +146,13 @@ static ssize_t queue_nomerges_store(struct request_queue *q, const char *page,
         unsigned long nm;
         ssize_t ret = queue_var_store(&nm, page, count);
 
+        spin_lock_irq(q->queue_lock);
         if (nm)
-               set_bit(QUEUE_FLAG_NOMERGES, &q->queue_flags);
+                queue_flag_set(QUEUE_FLAG_NOMERGES, q);
         else
-               clear_bit(QUEUE_FLAG_NOMERGES, &q->queue_flags);
+                queue_flag_clear(QUEUE_FLAG_NOMERGES, q);
 
+        spin_unlock_irq(q->queue_lock);
         return ret;
 }