[PATCH] mm: pagefault_{disable,enable}()
[linux-2.6.git] / include / asm-sparc64 / futex.h
1 #ifndef _SPARC64_FUTEX_H
2 #define _SPARC64_FUTEX_H
3
4 #include <linux/futex.h>
5 #include <asm/errno.h>
6 #include <asm/system.h>
7 #include <asm/uaccess.h>
8
9 #define __futex_cas_op(insn, ret, oldval, uaddr, oparg) \
10         __asm__ __volatile__(                           \
11         "\n1:   lduwa   [%3] %%asi, %2\n"               \
12         "       " insn "\n"                             \
13         "2:     casa    [%3] %%asi, %2, %1\n"           \
14         "       cmp     %2, %1\n"                       \
15         "       bne,pn  %%icc, 1b\n"                    \
16         "        mov    0, %0\n"                        \
17         "3:\n"                                          \
18         "       .section .fixup,#alloc,#execinstr\n"    \
19         "       .align  4\n"                            \
20         "4:     ba      3b\n"                           \
21         "        mov    %5, %0\n"                       \
22         "       .previous\n"                            \
23         "       .section __ex_table,\"a\"\n"            \
24         "       .align  4\n"                            \
25         "       .word   1b, 4b\n"                       \
26         "       .word   2b, 4b\n"                       \
27         "       .previous\n"                            \
28         : "=&r" (ret), "=&r" (oldval), "=&r" (tem)      \
29         : "r" (uaddr), "r" (oparg), "i" (-EFAULT)       \
30         : "memory")
31
32 static inline int futex_atomic_op_inuser(int encoded_op, int __user *uaddr)
33 {
34         int op = (encoded_op >> 28) & 7;
35         int cmp = (encoded_op >> 24) & 15;
36         int oparg = (encoded_op << 8) >> 20;
37         int cmparg = (encoded_op << 20) >> 20;
38         int oldval = 0, ret, tem;
39
40         if (unlikely(!access_ok(VERIFY_WRITE, uaddr, sizeof(int))))
41                 return -EFAULT;
42         if (unlikely((((unsigned long) uaddr) & 0x3UL)))
43                 return -EINVAL;
44
45         if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
46                 oparg = 1 << oparg;
47
48         pagefault_disable();
49
50         switch (op) {
51         case FUTEX_OP_SET:
52                 __futex_cas_op("mov\t%4, %1", ret, oldval, uaddr, oparg);
53                 break;
54         case FUTEX_OP_ADD:
55                 __futex_cas_op("add\t%2, %4, %1", ret, oldval, uaddr, oparg);
56                 break;
57         case FUTEX_OP_OR:
58                 __futex_cas_op("or\t%2, %4, %1", ret, oldval, uaddr, oparg);
59                 break;
60         case FUTEX_OP_ANDN:
61                 __futex_cas_op("and\t%2, %4, %1", ret, oldval, uaddr, oparg);
62                 break;
63         case FUTEX_OP_XOR:
64                 __futex_cas_op("xor\t%2, %4, %1", ret, oldval, uaddr, oparg);
65                 break;
66         default:
67                 ret = -ENOSYS;
68         }
69
70         pagefault_enable();
71
72         if (!ret) {
73                 switch (cmp) {
74                 case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
75                 case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
76                 case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
77                 case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
78                 case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
79                 case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
80                 default: ret = -ENOSYS;
81                 }
82         }
83         return ret;
84 }
85
86 static inline int
87 futex_atomic_cmpxchg_inatomic(int __user *uaddr, int oldval, int newval)
88 {
89         __asm__ __volatile__(
90         "\n1:   casa    [%3] %%asi, %2, %0\n"
91         "2:\n"
92         "       .section .fixup,#alloc,#execinstr\n"
93         "       .align  4\n"
94         "3:     ba      2b\n"
95         "        mov    %4, %0\n"
96         "       .previous\n"
97         "       .section __ex_table,\"a\"\n"
98         "       .align  4\n"
99         "       .word   1b, 3b\n"
100         "       .previous\n"
101         : "=r" (newval)
102         : "0" (newval), "r" (oldval), "r" (uaddr), "i" (-EFAULT)
103         : "memory");
104
105         return newval;
106 }
107
108 #endif /* !(_SPARC64_FUTEX_H) */