IOPRIO_CLASS_SHIFT   12 include/linux/ioprio.h #define IOPRIO_PRIO_MASK	((1UL << IOPRIO_CLASS_SHIFT) - 1)
IOPRIO_CLASS_SHIFT   14 include/linux/ioprio.h #define IOPRIO_PRIO_CLASS(mask)	((mask) >> IOPRIO_CLASS_SHIFT)
IOPRIO_CLASS_SHIFT   16 include/linux/ioprio.h #define IOPRIO_PRIO_VALUE(class, data)	(((class) << IOPRIO_CLASS_SHIFT) | data)