arch/riscv/include/asm/syscall.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2008-2009 Red Hat, Inc.  All rights reserved.
   4  * Copyright 2010 Tilera Corporation. All Rights Reserved.
   5  * Copyright 2015 Regents of the University of California, Berkeley
   6  *
   7  * See asm-generic/syscall.h for descriptions of what we must do here.
   8  */
   9
  10 #ifndef _ASM_RISCV_SYSCALL_H
  11 #define _ASM_RISCV_SYSCALL_H
  12
  13 #include <uapi/linux/audit.h>
  14 #include <linux/sched.h>
  15 #include <linux/err.h>
  16
  17 /* The array of function pointers for syscalls. */
  18 extern void *sys_call_table[];
  19
  20 /*
  21  * Only the low 32 bits of orig_r0 are meaningful, so we return int.
  22  * This importantly ignores the high bits on 64-bit, so comparisons
  23  * sign-extend the low 32 bits.
  24  */
  25 static inline int syscall_get_nr(struct task_struct *task,
  26                                  struct pt_regs *regs)
  27 {
  28         return regs->a7;
  29 }
  30
  31 static inline void syscall_set_nr(struct task_struct *task,
  32                                   struct pt_regs *regs,
  33                                   int sysno)
  34 {
  35         regs->a7 = sysno;
  36 }
  37
  38 static inline void syscall_rollback(struct task_struct *task,
  39                                     struct pt_regs *regs)
  40 {
  41         regs->a0 = regs->orig_a0;
  42 }
  43
  44 static inline long syscall_get_error(struct task_struct *task,
  45                                      struct pt_regs *regs)
  46 {
  47         unsigned long error = regs->a0;
  48
  49         return IS_ERR_VALUE(error) ? error : 0;
  50 }
  51
  52 static inline long syscall_get_return_value(struct task_struct *task,
  53                                             struct pt_regs *regs)
  54 {
  55         return regs->a0;
  56 }
  57
  58 static inline void syscall_set_return_value(struct task_struct *task,
  59                                             struct pt_regs *regs,
  60                                             int error, long val)
  61 {
  62         regs->a0 = (long) error ?: val;
  63 }
  64
  65 static inline void syscall_get_arguments(struct task_struct *task,
  66                                          struct pt_regs *regs,
  67                                          unsigned long *args)
  68 {
  69         args[0] = regs->orig_a0;
  70         args++;
  71         memcpy(args, &regs->a1, 5 * sizeof(args[0]));
  72 }
  73
  74 static inline void syscall_set_arguments(struct task_struct *task,
  75                                          struct pt_regs *regs,
  76                                          const unsigned long *args)
  77 {
  78         regs->orig_a0 = args[0];
  79         args++;
  80         memcpy(&regs->a1, args, 5 * sizeof(regs->a1));
  81 }
  82
  83 static inline int syscall_get_arch(struct task_struct *task)
  84 {
  85 #ifdef CONFIG_64BIT
  86         return AUDIT_ARCH_RISCV64;
  87 #else
  88         return AUDIT_ARCH_RISCV32;
  89 #endif
  90 }
  91
  92 #endif  /* _ASM_RISCV_SYSCALL_H */