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#ifndef FIO_LFSR_H
#define FIO_LFSR_H
#include <inttypes.h>
#define FIO_MAX_TAPS 6
struct lfsr_taps {
unsigned int length;
unsigned int taps[FIO_MAX_TAPS];
};
struct fio_lfsr {
uint64_t xormask;
uint64_t last_val;
uint64_t cached_bit;
uint64_t max_val;
uint64_t num_vals;
uint64_t cycle_length;
uint64_t cached_cycle_length;
unsigned int spin;
};
int lfsr_next(struct fio_lfsr *fl, uint64_t *off);
int lfsr_init(struct fio_lfsr *fl, uint64_t size,
uint64_t seed, unsigned int spin);
int lfsr_reset(struct fio_lfsr *fl, uint64_t seed);
#endif
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