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-rw-r--r--include/linux/random.h28
1 files changed, 28 insertions, 0 deletions
diff --git a/include/linux/random.h b/include/linux/random.h
index 25d02fe5c9b5..fb7ab9de5f36 100644
--- a/include/linux/random.h
+++ b/include/linux/random.h
@@ -40,6 +40,10 @@ struct rand_pool_info {
40 __u32 buf[0]; 40 __u32 buf[0];
41}; 41};
42 42
43struct rnd_state {
44 __u32 s1, s2, s3;
45};
46
43/* Exported functions */ 47/* Exported functions */
44 48
45#ifdef __KERNEL__ 49#ifdef __KERNEL__
@@ -74,6 +78,30 @@ unsigned long randomize_range(unsigned long start, unsigned long end, unsigned l
74u32 random32(void); 78u32 random32(void);
75void srandom32(u32 seed); 79void srandom32(u32 seed);
76 80
81u32 prandom32(struct rnd_state *);
82
83/*
84 * Handle minimum values for seeds
85 */
86static inline u32 __seed(u32 x, u32 m)
87{
88 return (x < m) ? x + m : x;
89}
90
91/**
92 * prandom32_seed - set seed for prandom32().
93 * @state: pointer to state structure to receive the seed.
94 * @seed: arbitrary 64-bit value to use as a seed.
95 */
96static inline void prandom32_seed(struct rnd_state *state, u64 seed)
97{
98 u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
99
100 state->s1 = __seed(i, 1);
101 state->s2 = __seed(i, 7);
102 state->s3 = __seed(i, 15);
103}
104
77#endif /* __KERNEL___ */ 105#endif /* __KERNEL___ */
78 106
79#endif /* _LINUX_RANDOM_H */ 107#endif /* _LINUX_RANDOM_H */