1b2441318SGreg Kroah-Hartman /* SPDX-License-Identifier: GPL-2.0 */ 24c637cd8SHarald Freudenberger /* 34c637cd8SHarald Freudenberger * Kernel interface for the s390 arch_random_* functions 44c637cd8SHarald Freudenberger * 5918e75f7SHarald Freudenberger * Copyright IBM Corp. 2017, 2022 64c637cd8SHarald Freudenberger * 74c637cd8SHarald Freudenberger * Author: Harald Freudenberger <freude@de.ibm.com> 84c637cd8SHarald Freudenberger * 94c637cd8SHarald Freudenberger */ 104c637cd8SHarald Freudenberger 114c637cd8SHarald Freudenberger #ifndef _ASM_S390_ARCHRANDOM_H 124c637cd8SHarald Freudenberger #define _ASM_S390_ARCHRANDOM_H 134c637cd8SHarald Freudenberger 144c637cd8SHarald Freudenberger #include <linux/static_key.h> 15918e75f7SHarald Freudenberger #include <linux/preempt.h> 164c637cd8SHarald Freudenberger #include <linux/atomic.h> 17e4f74400SJason A. Donenfeld #include <asm/cpacf.h> 184c637cd8SHarald Freudenberger 194c637cd8SHarald Freudenberger DECLARE_STATIC_KEY_FALSE(s390_arch_random_available); 204c637cd8SHarald Freudenberger extern atomic64_t s390_arch_random_counter; 214c637cd8SHarald Freudenberger arch_get_random_longs(unsigned long * v,size_t max_longs)22*d349ab99SJason A. Donenfeldstatic inline size_t __must_check arch_get_random_longs(unsigned long *v, size_t max_longs) 234c637cd8SHarald Freudenberger { 24*d349ab99SJason A. Donenfeld return 0; 254c637cd8SHarald Freudenberger } 264c637cd8SHarald Freudenberger arch_get_random_seed_longs(unsigned long * v,size_t max_longs)27*d349ab99SJason A. Donenfeldstatic inline size_t __must_check arch_get_random_seed_longs(unsigned long *v, size_t max_longs) 28f44fa887SHarald Freudenberger { 29918e75f7SHarald Freudenberger if (static_branch_likely(&s390_arch_random_available) && 30918e75f7SHarald Freudenberger in_task()) { 31*d349ab99SJason A. Donenfeld cpacf_trng(NULL, 0, (u8 *)v, max_longs * sizeof(*v)); 32*d349ab99SJason A. Donenfeld atomic64_add(max_longs * sizeof(*v), &s390_arch_random_counter); 33*d349ab99SJason A. Donenfeld return max_longs; 344c637cd8SHarald Freudenberger } 35*d349ab99SJason A. Donenfeld return 0; 364c637cd8SHarald Freudenberger } 374c637cd8SHarald Freudenberger 384c637cd8SHarald Freudenberger #endif /* _ASM_S390_ARCHRANDOM_H */ 39