1/* SPDX-License-Identifier: GPL-2.0 */
 2/*
 3 * Kernel interface for the s390 arch_random_* functions
 4 *
 5 * Copyright IBM Corp. 2017, 2022
 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#include <linux/static_key.h>
15#include <linux/preempt.h>
16#include <linux/atomic.h>
17#include <asm/cpacf.h>
18
19DECLARE_STATIC_KEY_FALSE(s390_arch_random_available);
20extern atomic64_t s390_arch_random_counter;
21
22static inline size_t __must_check arch_get_random_longs(unsigned long *v, size_t max_longs)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
23{
24	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
25}
26
27static inline size_t __must_check arch_get_random_seed_longs(unsigned long *v, size_t max_longs)
28{
29	if (static_branch_likely(&s390_arch_random_available) &&
30	    in_task()) {
31		cpacf_trng(NULL, 0, (u8 *)v, max_longs * sizeof(*v));
32		atomic64_add(max_longs * sizeof(*v), &s390_arch_random_counter);
33		return max_longs;
34	}
35	return 0;
36}
37
 
38#endif /* _ASM_S390_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
19DECLARE_STATIC_KEY_FALSE(s390_arch_random_available);
20extern atomic64_t s390_arch_random_counter;
21
22bool s390_arch_random_generate(u8 *buf, unsigned int nbytes);
23
24static inline bool arch_has_random(void)
25{
26	return false;
27}
28
29static inline bool arch_has_random_seed(void)
30{
31	if (static_branch_likely(&s390_arch_random_available))
32		return true;
33	return false;
34}
35
36static inline bool arch_get_random_long(unsigned long *v)
37{
38	return false;
39}
40
41static inline bool arch_get_random_int(unsigned int *v)
42{
43	return false;
44}
45
46static inline bool arch_get_random_seed_long(unsigned long *v)
47{
48	if (static_branch_likely(&s390_arch_random_available)) {
49		return s390_arch_random_generate((u8 *)v, sizeof(*v));
50	}
51	return false;
52}
53
54static inline bool arch_get_random_seed_int(unsigned int *v)
55{
56	if (static_branch_likely(&s390_arch_random_available)) {
57		return s390_arch_random_generate((u8 *)v, sizeof(*v));
 
 
 
58	}
59	return false;
60}
61
62#endif /* CONFIG_ARCH_RANDOM */
63#endif /* _ASM_S390_ARCHRANDOM_H */