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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/include/asm/archrandom.h | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/include/asm/archrandom.h')
-rw-r--r-- | arch/x86/include/asm/archrandom.h | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/arch/x86/include/asm/archrandom.h b/arch/x86/include/asm/archrandom.h new file mode 100644 index 000000000..02bae8e07 --- /dev/null +++ b/arch/x86/include/asm/archrandom.h @@ -0,0 +1,62 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * This file is part of the Linux kernel. + * + * Copyright (c) 2011-2014, Intel Corporation + * Authors: Fenghua Yu <fenghua.yu@intel.com>, + * H. Peter Anvin <hpa@linux.intel.com> + */ + +#ifndef ASM_X86_ARCHRANDOM_H +#define ASM_X86_ARCHRANDOM_H + +#include <asm/processor.h> +#include <asm/cpufeature.h> + +#define RDRAND_RETRY_LOOPS 10 + +/* Unconditional execution of RDRAND and RDSEED */ + +static inline bool __must_check rdrand_long(unsigned long *v) +{ + bool ok; + unsigned int retry = RDRAND_RETRY_LOOPS; + do { + asm volatile("rdrand %[out]" + CC_SET(c) + : CC_OUT(c) (ok), [out] "=r" (*v)); + if (ok) + return true; + } while (--retry); + return false; +} + +static inline bool __must_check rdseed_long(unsigned long *v) +{ + bool ok; + asm volatile("rdseed %[out]" + CC_SET(c) + : CC_OUT(c) (ok), [out] "=r" (*v)); + return ok; +} + +/* + * These are the generic interfaces; they must not be declared if the + * stubs in <linux/random.h> are to be invoked. + */ + +static inline size_t __must_check arch_get_random_longs(unsigned long *v, size_t max_longs) +{ + return max_longs && static_cpu_has(X86_FEATURE_RDRAND) && rdrand_long(v) ? 1 : 0; +} + +static inline size_t __must_check arch_get_random_seed_longs(unsigned long *v, size_t max_longs) +{ + return max_longs && static_cpu_has(X86_FEATURE_RDSEED) && rdseed_long(v) ? 1 : 0; +} + +#ifndef CONFIG_UML +void x86_init_rdrand(struct cpuinfo_x86 *c); +#endif + +#endif /* ASM_X86_ARCHRANDOM_H */ |