linux_dsm_epyc7002/arch/riscv/include/asm/syscall.h
Palmer Dabbelt e2c0cdfba7 RISC-V: User-facing API
This patch contains code that is in some way visible to the user:
including via system calls, the VDSO, module loading and signal
handling.  It also contains some generic code that is ABI visible.

Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>
2017-09-26 15:26:48 -07:00

103 lines
2.6 KiB
C

/*
* Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved.
* Copyright 2010 Tilera Corporation. All Rights Reserved.
* Copyright 2015 Regents of the University of California, Berkeley
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* See asm-generic/syscall.h for descriptions of what we must do here.
*/
#ifndef _ASM_RISCV_SYSCALL_H
#define _ASM_RISCV_SYSCALL_H
#include <linux/sched.h>
#include <linux/err.h>
/* The array of function pointers for syscalls. */
extern void *sys_call_table[];
/*
* Only the low 32 bits of orig_r0 are meaningful, so we return int.
* This importantly ignores the high bits on 64-bit, so comparisons
* sign-extend the low 32 bits.
*/
static inline int syscall_get_nr(struct task_struct *task,
struct pt_regs *regs)
{
return regs->a7;
}
static inline void syscall_set_nr(struct task_struct *task,
struct pt_regs *regs,
int sysno)
{
regs->a7 = sysno;
}
static inline void syscall_rollback(struct task_struct *task,
struct pt_regs *regs)
{
regs->a0 = regs->orig_a0;
}
static inline long syscall_get_error(struct task_struct *task,
struct pt_regs *regs)
{
unsigned long error = regs->a0;
return IS_ERR_VALUE(error) ? error : 0;
}
static inline long syscall_get_return_value(struct task_struct *task,
struct pt_regs *regs)
{
return regs->a0;
}
static inline void syscall_set_return_value(struct task_struct *task,
struct pt_regs *regs,
int error, long val)
{
regs->a0 = (long) error ?: val;
}
static inline void syscall_get_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
unsigned long *args)
{
BUG_ON(i + n > 6);
if (i == 0) {
args[0] = regs->orig_a0;
args++;
i++;
n--;
}
memcpy(args, &regs->a1 + i * sizeof(regs->a1), n * sizeof(args[0]));
}
static inline void syscall_set_arguments(struct task_struct *task,
struct pt_regs *regs,
unsigned int i, unsigned int n,
const unsigned long *args)
{
BUG_ON(i + n > 6);
if (i == 0) {
regs->orig_a0 = args[0];
args++;
i++;
n--;
}
memcpy(&regs->a1 + i * sizeof(regs->a1), args, n * sizeof(regs->a0));
}
#endif /* _ASM_RISCV_SYSCALL_H */