arch/loongarch/include/asm/vdso/getrandom.h

Source file repositories/reference/linux-study-clean/arch/loongarch/include/asm/vdso/getrandom.h

File Facts

System
Linux kernel
Corpus path
arch/loongarch/include/asm/vdso/getrandom.h
Extension
.h
Size
832 bytes
Lines
34
Domain
Architecture Layer
Bucket
arch/loongarch
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2024 Xi Ruoyao <xry111@xry111.site>. All Rights Reserved.
 */
#ifndef __ASM_VDSO_GETRANDOM_H
#define __ASM_VDSO_GETRANDOM_H

#ifndef __ASSEMBLER__

#include <asm/unistd.h>
#include <asm/vdso/vdso.h>

static __always_inline ssize_t getrandom_syscall(void *_buffer, size_t _len, unsigned int _flags)
{
	register long ret asm("a0");
	register long nr asm("a7") = __NR_getrandom;
	register void *buffer asm("a0") = _buffer;
	register size_t len asm("a1") = _len;
	register unsigned int flags asm("a2") = _flags;

	asm volatile(
	"      syscall 0\n"
	: "=r" (ret)
	: "r" (nr), "r" (buffer), "r" (len), "r" (flags)
	: "$t0", "$t1", "$t2", "$t3", "$t4", "$t5", "$t6", "$t7", "$t8",
	  "memory");

	return ret;
}

#endif /* !__ASSEMBLER__ */

#endif /* __ASM_VDSO_GETRANDOM_H */

Annotation

Implementation Notes