cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystem
[linux-2.6.git] / arch / x86 / include / asm / futex.h
1 #ifndef _ASM_X86_FUTEX_H
2 #define _ASM_X86_FUTEX_H
3
4 #ifdef __KERNEL__
5
6 #include <linux/futex.h>
7 #include <linux/uaccess.h>
8
9 #include <asm/asm.h>
10 #include <asm/errno.h>
11 #include <asm/processor.h>
12 #include <asm/system.h>
13
14 #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg)     \
15         asm volatile("1:\t" insn "\n"                           \
16                      "2:\t.section .fixup,\"ax\"\n"             \
17                      "3:\tmov\t%3, %1\n"                        \
18                      "\tjmp\t2b\n"                              \
19                      "\t.previous\n"                            \
20                      _ASM_EXTABLE(1b, 3b)                       \
21                      : "=r" (oldval), "=r" (ret), "+m" (*uaddr) \
22                      : "i" (-EFAULT), "0" (oparg), "1" (0))
23
24 #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg)     \
25         asm volatile("1:\tmovl  %2, %0\n"                       \
26                      "\tmovl\t%0, %3\n"                         \
27                      "\t" insn "\n"                             \
28                      "2:\t" LOCK_PREFIX "cmpxchgl %3, %2\n"     \
29                      "\tjnz\t1b\n"                              \
30                      "3:\t.section .fixup,\"ax\"\n"             \
31                      "4:\tmov\t%5, %1\n"                        \
32                      "\tjmp\t3b\n"                              \
33                      "\t.previous\n"                            \
34                      _ASM_EXTABLE(1b, 4b)                       \
35                      _ASM_EXTABLE(2b, 4b)                       \
36                      : "=&a" (oldval), "=&r" (ret),             \
37                        "+m" (*uaddr), "=&r" (tem)               \
38                      : "r" (oparg), "i" (-EFAULT), "1" (0))
39
40 static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
41 {
42         int op = (encoded_op >> 28) & 7;
43         int cmp = (encoded_op >> 24) & 15;
44         int oparg = (encoded_op << 8) >> 20;
45         int cmparg = (encoded_op << 20) >> 20;
46         int oldval = 0, ret, tem;
47
48         if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
49                 oparg = 1 << oparg;
50
51         if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
52                 return -EFAULT;
53
54 #if defined(CONFIG_X86_32) && !defined(CONFIG_X86_BSWAP)
55         /* Real i386 machines can only support FUTEX_OP_SET */
56         if (op != FUTEX_OP_SET && boot_cpu_data.x86 == 3)
57                 return -ENOSYS;
58 #endif
59
60         pagefault_disable();
61
62         switch (op) {
63         case FUTEX_OP_SET:
64                 __futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg);
65                 break;
66         case FUTEX_OP_ADD:
67                 __futex_atomic_op1(LOCK_PREFIX "xaddl %0, %2", ret, oldval,
68                                    uaddr, oparg);
69                 break;
70         case FUTEX_OP_OR:
71                 __futex_atomic_op2("orl %4, %3", ret, oldval, uaddr, oparg);
72                 break;
73         case FUTEX_OP_ANDN:
74                 __futex_atomic_op2("andl %4, %3", ret, oldval, uaddr, ~oparg);
75                 break;
76         case FUTEX_OP_XOR:
77                 __futex_atomic_op2("xorl %4, %3", ret, oldval, uaddr, oparg);
78                 break;
79         default:
80                 ret = -ENOSYS;
81         }
82
83         pagefault_enable();
84
85         if (!ret) {
86                 switch (cmp) {
87                 case FUTEX_OP_CMP_EQ:
88                         ret = (oldval == cmparg);
89                         break;
90                 case FUTEX_OP_CMP_NE:
91                         ret = (oldval != cmparg);
92                         break;
93                 case FUTEX_OP_CMP_LT:
94                         ret = (oldval < cmparg);
95                         break;
96                 case FUTEX_OP_CMP_GE:
97                         ret = (oldval >= cmparg);
98                         break;
99                 case FUTEX_OP_CMP_LE:
100                         ret = (oldval <= cmparg);
101                         break;
102                 case FUTEX_OP_CMP_GT:
103                         ret = (oldval > cmparg);
104                         break;
105                 default:
106                         ret = -ENOSYS;
107                 }
108         }
109         return ret;
110 }
111
112 static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
113                                                 u32 oldval, u32 newval)
114 {
115         int ret = 0;
116
117 #if defined(CONFIG_X86_32) && !defined(CONFIG_X86_BSWAP)
118         /* Real i386 machines have no cmpxchg instruction */
119         if (boot_cpu_data.x86 == 3)
120                 return -ENOSYS;
121 #endif
122
123         if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
124                 return -EFAULT;
125
126         asm volatile("1:\t" LOCK_PREFIX "cmpxchgl %4, %2\n"
127                      "2:\t.section .fixup, \"ax\"\n"
128                      "3:\tmov     %3, %0\n"
129                      "\tjmp     2b\n"
130                      "\t.previous\n"
131                      _ASM_EXTABLE(1b, 3b)
132                      : "+r" (ret), "=a" (oldval), "+m" (*uaddr)
133                      : "i" (-EFAULT), "r" (newval), "1" (oldval)
134                      : "memory"
135         );
136
137         *uval = oldval;
138         return ret;
139 }
140
141 #endif
142 #endif /* _ASM_X86_FUTEX_H */