Blame view

kernel/linux-rt-4.4.41/arch/ia64/include/asm/futex.h 3.15 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
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
  #ifndef _ASM_FUTEX_H
  #define _ASM_FUTEX_H
  
  #include <linux/futex.h>
  #include <linux/uaccess.h>
  #include <asm/errno.h>
  
  #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \
  do {									\
  	register unsigned long r8 __asm ("r8") = 0;			\
  	__asm__ __volatile__(						\
  		"	mf;;					
  "	\
  		"[1:] "	insn ";;				
  "	\
  		"	.xdata4 \"__ex_table\", 1b-., 2f-.	
  "	\
  		"[2:]"							\
  		: "+r" (r8), "=r" (oldval)				\
  		: "r" (uaddr), "r" (oparg)				\
  		: "memory");						\
  	ret = r8;							\
  } while (0)
  
  #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \
  do {									\
  	register unsigned long r8 __asm ("r8") = 0;			\
  	int val, newval;						\
  	do {								\
  		__asm__ __volatile__(					\
  			"	mf;;				  
  "	\
  			"[1:]	ld4 %3=[%4];;			  
  "	\
  			"	mov %2=%3			  
  "	\
  				insn	";;			  
  "	\
  			"	mov ar.ccv=%2;;			  
  "	\
  			"[2:]	cmpxchg4.acq %1=[%4],%3,ar.ccv;;  
  "	\
  			"	.xdata4 \"__ex_table\", 1b-., 3f-.
  "	\
  			"	.xdata4 \"__ex_table\", 2b-., 3f-.
  "	\
  			"[3:]"						\
  			: "+r" (r8), "=r" (val), "=&r" (oldval),	\
  			   "=&r" (newval)				\
  			: "r" (uaddr), "r" (oparg)			\
  			: "memory");					\
  		if (unlikely (r8))					\
  			break;						\
  	} while (unlikely (val != oldval));				\
  	ret = r8;							\
  } while (0)
  
  static inline int
  futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr)
  {
  	int op = (encoded_op >> 28) & 7;
  	int cmp = (encoded_op >> 24) & 15;
  	int oparg = (encoded_op << 8) >> 20;
  	int cmparg = (encoded_op << 20) >> 20;
  	int oldval = 0, ret;
  	if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
  		oparg = 1 << oparg;
  
  	if (! access_ok (VERIFY_WRITE, uaddr, sizeof(u32)))
  		return -EFAULT;
  
  	pagefault_disable();
  
  	switch (op) {
  	case FUTEX_OP_SET:
  		__futex_atomic_op1("xchg4 %1=[%2],%3", ret, oldval, uaddr,
  				   oparg);
  		break;
  	case FUTEX_OP_ADD:
  		__futex_atomic_op2("add %3=%3,%5", ret, oldval, uaddr, oparg);
  		break;
  	case FUTEX_OP_OR:
  		__futex_atomic_op2("or %3=%3,%5", ret, oldval, uaddr, oparg);
  		break;
  	case FUTEX_OP_ANDN:
  		__futex_atomic_op2("and %3=%3,%5", ret, oldval, uaddr,
  				   ~oparg);
  		break;
  	case FUTEX_OP_XOR:
  		__futex_atomic_op2("xor %3=%3,%5", ret, oldval, uaddr, oparg);
  		break;
  	default:
  		ret = -ENOSYS;
  	}
  
  	pagefault_enable();
  
  	if (!ret) {
  		switch (cmp) {
  		case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
  		case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
  		case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
  		case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
  		case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
  		case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
  		default: ret = -ENOSYS;
  		}
  	}
  	return ret;
  }
  
  static inline int
  futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
  			      u32 oldval, u32 newval)
  {
  	if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
  		return -EFAULT;
  
  	{
  		register unsigned long r8 __asm ("r8") = 0;
  		unsigned long prev;
  		__asm__ __volatile__(
  			"	mf;;					
  "
  			"	mov ar.ccv=%4;;				
  "
  			"[1:]	cmpxchg4.acq %1=[%2],%3,ar.ccv		
  "
  			"	.xdata4 \"__ex_table\", 1b-., 2f-.	
  "
  			"[2:]"
  			: "+r" (r8), "=&r" (prev)
  			: "r" (uaddr), "r" (newval),
  			  "rO" ((long) (unsigned) oldval)
  			: "memory");
  		*uval = prev;
  		return r8;
  	}
  }
  
  #endif /* _ASM_FUTEX_H */