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 /*
 * Calling wait_on_buffer() for a zero-ref buffer is illegal, so we call into
 * __wait_on_buffer() just to trip a debug check.  Because debug code in inline
 * functions is bloaty.
 */
static inline void wait_on_buffer(struct buffer_head *bh)
{
	might_sleep();
if (buffer_locked(bh) || atomic_read(&bh->b_count) == 0)
__wait_on_buffer(bh);
}