Blame view

kernel/linux-rt-4.4.41/arch/powerpc/include/asm/syscall.h 2.8 KB
5113f6f70   김현기   kernel add
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
  /*
   * Access to user system call parameters and results
   *
   * Copyright (C) 2008 Red Hat, Inc.  All rights reserved.
   *
   * This copyrighted material is made available to anyone wishing to use,
   * modify, copy, or redistribute it subject to the terms and conditions
   * of the GNU General Public License v.2.
   *
   * See asm-generic/syscall.h for descriptions of what we must do here.
   */
  
  #ifndef _ASM_SYSCALL_H
  #define _ASM_SYSCALL_H	1
  
  #include <uapi/linux/audit.h>
  #include <linux/sched.h>
  #include <linux/thread_info.h>
  
  /* ftrace syscalls requires exporting the sys_call_table */
  #ifdef CONFIG_FTRACE_SYSCALLS
  extern const unsigned long sys_call_table[];
  #endif /* CONFIG_FTRACE_SYSCALLS */
  
  static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
  {
  	/*
  	 * Note that we are returning an int here. That means 0xffffffff, ie.
  	 * 32-bit negative 1, will be interpreted as -1 on a 64-bit kernel.
  	 * This is important for seccomp so that compat tasks can set r0 = -1
  	 * to reject the syscall.
  	 */
  	return TRAP(regs) == 0xc00 ? regs->gpr[0] : -1;
  }
  
  static inline void syscall_rollback(struct task_struct *task,
  				    struct pt_regs *regs)
  {
  	regs->gpr[3] = regs->orig_gpr3;
  }
  
  static inline long syscall_get_return_value(struct task_struct *task,
  					    struct pt_regs *regs)
  {
  	return regs->gpr[3];
  }
  
  static inline void syscall_set_return_value(struct task_struct *task,
  					    struct pt_regs *regs,
  					    int error, long val)
  {
  	/*
  	 * In the general case it's not obvious that we must deal with CCR
  	 * here, as the syscall exit path will also do that for us. However
  	 * there are some places, eg. the signal code, which check ccr to
  	 * decide if the value in r3 is actually an error.
  	 */
  	if (error) {
  		regs->ccr |= 0x10000000L;
  		regs->gpr[3] = error;
  	} else {
  		regs->ccr &= ~0x10000000L;
  		regs->gpr[3] = val;
  	}
  }
  
  static inline void syscall_get_arguments(struct task_struct *task,
  					 struct pt_regs *regs,
  					 unsigned int i, unsigned int n,
  					 unsigned long *args)
  {
  	unsigned long val, mask = -1UL;
  
  	BUG_ON(i + n > 6);
  
  #ifdef CONFIG_COMPAT
  	if (test_tsk_thread_flag(task, TIF_32BIT))
  		mask = 0xffffffff;
  #endif
  	while (n--) {
  		if (n == 0 && i == 0)
  			val = regs->orig_gpr3;
  		else
  			val = regs->gpr[3 + i + n];
  
  		args[n] = val & mask;
  	}
  }
  
  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);
  	memcpy(&regs->gpr[3 + i], args, n * sizeof(args[0]));
  
  	/* Also copy the first argument into orig_gpr3 */
  	if (i == 0 && n > 0)
  		regs->orig_gpr3 = args[0];
  }
  
  static inline int syscall_get_arch(void)
  {
  	int arch = is_32bit_task() ? AUDIT_ARCH_PPC : AUDIT_ARCH_PPC64;
  #ifdef __LITTLE_ENDIAN__
  	arch |= __AUDIT_ARCH_LE;
  #endif
  	return arch;
  }
  #endif	/* _ASM_SYSCALL_H */