arch/powerpc/include/asm/syscall.h

   1 /*
   2  * Access to user system call parameters and results
   3  *
   4  * Copyright (C) 2008 Red Hat, Inc.  All rights reserved.
   5  *
   6  * This copyrighted material is made available to anyone wishing to use,
   7  * modify, copy, or redistribute it subject to the terms and conditions
   8  * of the GNU General Public License v.2.
   9  *
  10  * See asm-generic/syscall.h for descriptions of what we must do here.
  11  */
  12
  13 #ifndef _ASM_SYSCALL_H
  14 #define _ASM_SYSCALL_H  1
  15
  16 #include <uapi/linux/audit.h>
  17 #include <linux/sched.h>
  18 #include <linux/thread_info.h>
  19
  20 /* ftrace syscalls requires exporting the sys_call_table */
  21 #ifdef CONFIG_FTRACE_SYSCALLS
  22 extern const unsigned long sys_call_table[];
  23 #endif /* CONFIG_FTRACE_SYSCALLS */
  24
  25 static inline long syscall_get_nr(struct task_struct *task,
  26                                   struct pt_regs *regs)
  27 {
  28         return TRAP(regs) == 0xc00 ? regs->gpr[0] : -1L;
  29 }
  30
  31 static inline void syscall_rollback(struct task_struct *task,
  32                                     struct pt_regs *regs)
  33 {
  34         regs->gpr[3] = regs->orig_gpr3;
  35 }
  36
  37 static inline long syscall_get_error(struct task_struct *task,
  38                                      struct pt_regs *regs)
  39 {
  40         return (regs->ccr & 0x10000000) ? -regs->gpr[3] : 0;
  41 }
  42
  43 static inline long syscall_get_return_value(struct task_struct *task,
  44                                             struct pt_regs *regs)
  45 {
  46         return regs->gpr[3];
  47 }
  48
  49 static inline void syscall_set_return_value(struct task_struct *task,
  50                                             struct pt_regs *regs,
  51                                             int error, long val)
  52 {
  53         if (error) {
  54                 regs->ccr |= 0x10000000L;
  55                 regs->gpr[3] = -error;
  56         } else {
  57                 regs->ccr &= ~0x10000000L;
  58                 regs->gpr[3] = val;
  59         }
  60 }
  61
  62 static inline void syscall_get_arguments(struct task_struct *task,
  63                                          struct pt_regs *regs,
  64                                          unsigned int i, unsigned int n,
  65                                          unsigned long *args)
  66 {
  67         BUG_ON(i + n > 6);
  68 #ifdef CONFIG_PPC64
  69         if (test_tsk_thread_flag(task, TIF_32BIT)) {
  70                 /*
  71                  * Zero-extend 32-bit argument values.  The high bits are
  72                  * garbage ignored by the actual syscall dispatch.
  73                  */
  74                 while (n-- > 0)
  75                         args[n] = (u32) regs->gpr[3 + i + n];
  76                 return;
  77         }
  78 #endif
  79         memcpy(args, &regs->gpr[3 + i], n * sizeof(args[0]));
  80 }
  81
  82 static inline void syscall_set_arguments(struct task_struct *task,
  83                                          struct pt_regs *regs,
  84                                          unsigned int i, unsigned int n,
  85                                          const unsigned long *args)
  86 {
  87         BUG_ON(i + n > 6);
  88         memcpy(&regs->gpr[3 + i], args, n * sizeof(args[0]));
  89 }
  90
  91 static inline int syscall_get_arch(void)
  92 {
  93         return is_32bit_task() ? AUDIT_ARCH_PPC : AUDIT_ARCH_PPC64;
  94 }
  95 #endif  /* _ASM_SYSCALL_H */