#include <linux/seqlock.h>
#include <linux/unroll.h>

#define __scoped_seqlock_read(lock, s, cond) \
	unrolled_full for (struct { unsigned long phase, data; } s = { 0 }; \
		s.phase < 3 && cond(lock, s.phase, &s.data); s.phase++)

#define scoped_seqlock_read(lock)      \
       __scoped_seqlock_read(lock, __UNIQUE_ID(s), __seqlock_cond)

#define scoped_seqlock_read_irqsave(lock) \
	__scoped_seqlock_read(lock, __UNIQUE_ID(s), __seqlock_cond_irqsave)

/* Do the phase action and return true if the loop should go on */
static __always_inline bool __seqlock_cond(seqlock_t *lock, int phase, unsigned long *data)
{
	switch (phase) {
	case 0:
		*data = read_seqbegin(lock);
		return true;
	case 1:
		if (!read_seqretry(lock, *data))
			return false;
		read_seqlock_excl(lock);
		return true;
	default:
		read_sequnlock_excl(lock);
		return false;
	}		
}

static __always_inline bool __seqlock_cond_irqsave(seqlock_t *lock, int phase, unsigned long *data)
{
	switch (phase) {
	case 0:
		*data = read_seqbegin(lock);
		return true;
	case 1:
		if (!read_seqretry(lock, *data))  
			return false;
		read_seqlock_excl_irqsave(lock, *data);
		return true;
	default:
		read_sequnlock_excl_irqrestore(lock, *data);
		return false;
	}
}

void testme(seqlock_t *lock);
void testme(seqlock_t *lock)
{
	scoped_seqlock_read_irqsave(lock) {
		asm volatile("TEST");
	}		
}