md: add __acquires/__releases annotations to (un)lock_two_stripes

This tells sparse that we acquire/release the two stripe locks and
avoids a warning.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <songliubraving@fb.com>

drivers/md/raid5.c

@@ -711,6 +711,8 @@ static bool is_full_stripe_write(struct stripe_head *sh)
 }
 
 static void lock_two_stripes(struct stripe_head *sh1, struct stripe_head *sh2)
+		__acquires(&sh1->stripe_lock)
+		__acquires(&sh2->stripe_lock)
 {
 	if (sh1 > sh2) {
 		spin_lock_irq(&sh2->stripe_lock);
@@ -722,6 +724,8 @@ static void lock_two_stripes(struct stripe_head *sh1, struct stripe_head *sh2)
 }
 
 static void unlock_two_stripes(struct stripe_head *sh1, struct stripe_head *sh2)
+		__releases(&sh1->stripe_lock)
+		__releases(&sh2->stripe_lock)
 {
 	spin_unlock(&sh1->stripe_lock);
 	spin_unlock_irq(&sh2->stripe_lock);