getrandom.h

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Copyright (C) 2024 Xi Ruoyao <xry111@xry111.site>. All Rights Reserved.
 4 */
 5#ifndef __ASM_VDSO_GETRANDOM_H
 6#define __ASM_VDSO_GETRANDOM_H
 7
 8#ifndef __ASSEMBLER__
 9
10#include <asm/unistd.h>
11#include <asm/vdso/vdso.h>
12
13static __always_inline ssize_t getrandom_syscall(void *_buffer, size_t _len, unsigned int _flags)
14{
15	register long ret asm("a0");
16	register long nr asm("a7") = __NR_getrandom;
17	register void *buffer asm("a0") = _buffer;
18	register size_t len asm("a1") = _len;
19	register unsigned int flags asm("a2") = _flags;
20
21	asm volatile(
22	"      syscall 0\n"
23	: "=r" (ret)
24	: "r" (nr), "r" (buffer), "r" (len), "r" (flags)
25	: "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7", "$t8",
26	  "memory");
27
28	return ret;
29}
30
31#endif /* !__ASSEMBLER__ */
32
33#endif /* __ASM_VDSO_GETRANDOM_H */