1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Kernel interface for the s390 arch_random_* functions
4  *
5  * Copyright IBM Corp. 2017, 2020
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_get_random_long(unsigned long *v);
23 bool s390_arch_random_generate(u8 *buf, unsigned int nbytes);
24 
arch_get_random_long(unsigned long * v)25 static inline bool __must_check arch_get_random_long(unsigned long *v)
26 {
27 	if (static_branch_likely(&s390_arch_random_available))
28 		return s390_arch_get_random_long(v);
29 	return false;
30 }
31 
arch_get_random_int(unsigned int * v)32 static inline bool __must_check arch_get_random_int(unsigned int *v)
33 {
34 	return false;
35 }
36 
arch_get_random_seed_long(unsigned long * v)37 static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
38 {
39 	if (static_branch_likely(&s390_arch_random_available)) {
40 		return s390_arch_random_generate((u8 *)v, sizeof(*v));
41 	}
42 	return false;
43 }
44 
arch_get_random_seed_int(unsigned int * v)45 static inline bool __must_check arch_get_random_seed_int(unsigned int *v)
46 {
47 	if (static_branch_likely(&s390_arch_random_available)) {
48 		return s390_arch_random_generate((u8 *)v, sizeof(*v));
49 	}
50 	return false;
51 }
52 
53 #endif /* CONFIG_ARCH_RANDOM */
54 #endif /* _ASM_S390_ARCHRANDOM_H */
55