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_rollback(struct task_struct *task,
  32                                     struct pt_regs *regs)
  33 {
  34         regs->a0 = regs->orig_a0;
  35 }
  36
  37 static inline long syscall_get_error(struct task_struct *task,
  38                                      struct pt_regs *regs)
  39 {
  40         unsigned long error = regs->a0;
  41
  42         return IS_ERR_VALUE(error) ? error : 0;
  43 }
  44
  45 static inline long syscall_get_return_value(struct task_struct *task,
  46                                             struct pt_regs *regs)
  47 {
  48         return regs->a0;
  49 }
  50
  51 static inline void syscall_set_return_value(struct task_struct *task,
  52                                             struct pt_regs *regs,
  53                                             int error, long val)
  54 {
  55         regs->a0 = (long) error ?: val;
  56 }
  57
  58 static inline void syscall_get_arguments(struct task_struct *task,
  59                                          struct pt_regs *regs,
  60                                          unsigned long *args)
  61 {
  62         args[0] = regs->orig_a0;
  63         args++;
  64         memcpy(args, &regs->a1, 5 * sizeof(args[0]));
  65 }
  66
  67 static inline void syscall_set_arguments(struct task_struct *task,
  68                                          struct pt_regs *regs,
  69                                          const unsigned long *args)
  70 {
  71         regs->orig_a0 = args[0];
  72         args++;
  73         memcpy(&regs->a1, args, 5 * sizeof(regs->a1));
  74 }
  75
  76 static inline int syscall_get_arch(struct task_struct *task)
  77 {
  78 #ifdef CONFIG_64BIT
  79         return AUDIT_ARCH_RISCV64;
  80 #else
  81         return AUDIT_ARCH_RISCV32;
  82 #endif
  83 }
  84
  85 #endif  /* _ASM_RISCV_SYSCALL_H */