arch/s390/include/asm/archrandom.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Kernel interface for the s390 arch_random_* functions
   4  *
   5  * Copyright IBM Corp. 2017
   6  *
   7  * Author: Harald Freudenberger <freude@de.ibm.com>
   8  *
   9  */
  10
  11 #ifndef _ASM_S390_ARCHRANDOM_H
  12 #define _ASM_S390_ARCHRANDOM_H
  13
  14 #ifdef CONFIG_ARCH_RANDOM
  15
  16 #include <linux/static_key.h>
  17 #include <linux/atomic.h>
  18
  19 DECLARE_STATIC_KEY_FALSE(s390_arch_random_available);
  20 extern atomic64_t s390_arch_random_counter;
  21
  22 bool s390_arch_random_generate(u8 *buf, unsigned int nbytes);
  23
  24 static inline bool __must_check arch_get_random_long(unsigned long *v)
  25 {
  26         return false;
  27 }
  28
  29 static inline bool __must_check arch_get_random_int(unsigned int *v)
  30 {
  31         return false;
  32 }
  33
  34 static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
  35 {
  36         if (static_branch_likely(&s390_arch_random_available)) {
  37                 return s390_arch_random_generate((u8 *)v, sizeof(*v));
  38         }
  39         return false;
  40 }
  41
  42 static inline bool __must_check arch_get_random_seed_int(unsigned int *v)
  43 {
  44         if (static_branch_likely(&s390_arch_random_available)) {
  45                 return s390_arch_random_generate((u8 *)v, sizeof(*v));
  46         }
  47         return false;
  48 }
  49
  50 #endif /* CONFIG_ARCH_RANDOM */
  51 #endif /* _ASM_S390_ARCHRANDOM_H */