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/* SPDX-License-Identifier: GPL-2.0 */#ifndef __TOOLS_LINUX_PRANDOM_H#define __TOOLS_LINUX_PRANDOM_H #include <linux/types.h> struct rnd_state {	__u32 s1, s2, s3, s4;}; /* * Handle minimum values for seeds */static inline u32 __seed(u32 x, u32 m){	return (x < m) ? x + m : x;} /** * prandom_seed_state - set seed for prandom_u32_state(). * @state: pointer to state structure to receive the seed. * @seed: arbitrary 64-bit value to use as a seed. */static inline void prandom_seed_state(struct rnd_state *state, u64 seed){	u32 i = ((seed >> 32) ^ (seed << 10) ^ seed) & 0xffffffffUL; 	state->s1 = __seed(i,   2U);	state->s2 = __seed(i,   8U);	state->s3 = __seed(i,  16U);	state->s4 = __seed(i, 128U);} /** *	prandom_u32_state - seeded pseudo-random number generator. *	@state: pointer to state structure holding seeded state. * *	This is used for pseudo-randomness with no outside seeding. *	For more random results, use get_random_u32(). */static inline u32 prandom_u32_state(struct rnd_state *state){#define TAUSWORTHE(s, a, b, c, d) (((s & c) << d) ^ (((s << a) ^ s) >> b))	state->s1 = TAUSWORTHE(state->s1,  6U, 13U, 4294967294U, 18U);	state->s2 = TAUSWORTHE(state->s2,  2U, 27U, 4294967288U,  2U);	state->s3 = TAUSWORTHE(state->s3, 13U, 21U, 4294967280U,  7U);	state->s4 = TAUSWORTHE(state->s4,  3U, 12U, 4294967168U, 13U); 	return (state->s1 ^ state->s2 ^ state->s3 ^ state->s4);}#endif // __TOOLS_LINUX_PRANDOM_H