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#ifndef __BACKPORT_RANDOM_H
#define __BACKPORT_RANDOM_H
#include_next <linux/random.h>
#include <linux/version.h>
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,8,0)
/* backports 496f2f9 */
#define prandom_seed(_seed) srandom32(_seed)
#define prandom_u32() random32()
#define prandom_u32_state(_state) prandom32(_state)
/* backport 6582c665d6b882dad8329e05749fbcf119f1ab88 */
#define prandom_bytes LINUX_BACKPORT(prandom_bytes)
void prandom_bytes(void *buf, int bytes);
#endif
#if LINUX_VERSION_CODE < KERNEL_VERSION(3,14,0)
/**
* prandom_u32_max - returns a pseudo-random number in interval [0, ep_ro)
* @ep_ro: right open interval endpoint
*
* Returns a pseudo-random number that is in interval [0, ep_ro). Note
* that the result depends on PRNG being well distributed in [0, ~0U]
* u32 space. Here we use maximally equidistributed combined Tausworthe
* generator, that is, prandom_u32(). This is useful when requesting a
* random index of an array containing ep_ro elements, for example.
*
* Returns: pseudo-random number in interval [0, ep_ro)
*/
#define prandom_u32_max LINUX_BACKPORT(prandom_u32_max)
static inline u32 prandom_u32_max(u32 ep_ro)
{
return (u32)(((u64) prandom_u32() * ep_ro) >> 32);
}
#endif /* LINUX_VERSION_CODE < KERNEL_VERSION(3,14,0) */
#endif /* __BACKPORT_RANDOM_H */
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