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Diffstat (limited to 'include/linux/random.h')
-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 {
__u32 buf[0];
};
+struct rnd_state {
+ __u32 s1, s2, s3;
+};
+
/* Exported functions */
#ifdef __KERNEL__
@@ -74,6 +78,30 @@ unsigned long randomize_range(unsigned long start, unsigned long end, unsigned l
u32 random32(void);
void srandom32(u32 seed);
+u32 prandom32(struct rnd_state *);
+
+/*
+ * Handle minimum values for seeds
+ */
+static inline u32 __seed(u32 x, u32 m)
+{
+ return (x < m) ? x + m : x;
+}
+
+/**
+ * prandom32_seed - set seed for prandom32().
+ * @state: pointer to state structure to receive the seed.
+ * @seed: arbitrary 64-bit value to use as a seed.
+ */
+static inline void prandom32_seed(struct rnd_state *state, u64 seed)
+{
+ u32 i = (seed >> 32) ^ (seed << 10) ^ seed;
+
+ state->s1 = __seed(i, 1);
+ state->s2 = __seed(i, 7);
+ state->s3 = __seed(i, 15);
+}
+
#endif /* __KERNEL___ */
#endif /* _LINUX_RANDOM_H */