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 #include <asm/cpacf.h> 19 20 DECLARE_STATIC_KEY_FALSE(s390_arch_random_available); 21 extern atomic64_t s390_arch_random_counter; 22 s390_arch_random_generate(u8 * buf,unsigned int nbytes)23static void s390_arch_random_generate(u8 *buf, unsigned int nbytes) 24 { 25 cpacf_trng(NULL, 0, buf, nbytes); 26 atomic64_add(nbytes, &s390_arch_random_counter); 27 } 28 arch_has_random(void)29static inline bool arch_has_random(void) 30 { 31 if (static_branch_likely(&s390_arch_random_available)) 32 return true; 33 return false; 34 } 35 arch_has_random_seed(void)36static inline bool arch_has_random_seed(void) 37 { 38 return arch_has_random(); 39 } 40 arch_get_random_long(unsigned long * v)41static inline bool arch_get_random_long(unsigned long *v) 42 { 43 if (static_branch_likely(&s390_arch_random_available)) { 44 s390_arch_random_generate((u8 *)v, sizeof(*v)); 45 return true; 46 } 47 return false; 48 } 49 arch_get_random_int(unsigned int * v)50static inline bool arch_get_random_int(unsigned int *v) 51 { 52 if (static_branch_likely(&s390_arch_random_available)) { 53 s390_arch_random_generate((u8 *)v, sizeof(*v)); 54 return true; 55 } 56 return false; 57 } 58 arch_get_random_seed_long(unsigned long * v)59static inline bool arch_get_random_seed_long(unsigned long *v) 60 { 61 return arch_get_random_long(v); 62 } 63 arch_get_random_seed_int(unsigned int * v)64static inline bool arch_get_random_seed_int(unsigned int *v) 65 { 66 return arch_get_random_int(v); 67 } 68 69 #endif /* CONFIG_ARCH_RANDOM */ 70 #endif /* _ASM_S390_ARCHRANDOM_H */ 71