ia64/xen-unstable

view linux-2.6-xen-sparse/include/asm-i386/futex.h @ 9296:f85bb99187bf

Update interface documentation to include sched_op_new hypercall
and clean up the style a bit. Also clean up the sched_op_new
description in the sched.h public header.

Signed-off-by: Keir Fraser <keir@xensource.com>
author kaf24@firebug.cl.cam.ac.uk
date Wed Mar 15 19:19:22 2006 +0100 (2006-03-15)
parents 2494b4e00cbb
children
line source
1 #ifndef _ASM_FUTEX_H
2 #define _ASM_FUTEX_H
4 #ifdef __KERNEL__
6 #include <linux/futex.h>
7 #include <asm/errno.h>
8 #include <asm/system.h>
9 #include <asm/processor.h>
10 #include <asm/uaccess.h>
12 #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \
13 __asm__ __volatile ( \
14 "1: " insn "\n" \
15 "2: .section .fixup,\"ax\"\n\
16 3: mov %3, %1\n\
17 jmp 2b\n\
18 .previous\n\
19 .section __ex_table,\"a\"\n\
20 .align 8\n\
21 .long 1b,3b\n\
22 .previous" \
23 : "=r" (oldval), "=r" (ret), "=m" (*uaddr) \
24 : "i" (-EFAULT), "m" (*uaddr), "0" (oparg), "1" (0))
26 #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \
27 __asm__ __volatile ( \
28 "1: movl %2, %0\n\
29 movl %0, %3\n" \
30 insn "\n" \
31 "2: " LOCK "cmpxchgl %3, %2\n\
32 jnz 1b\n\
33 3: .section .fixup,\"ax\"\n\
34 4: mov %5, %1\n\
35 jmp 3b\n\
36 .previous\n\
37 .section __ex_table,\"a\"\n\
38 .align 8\n\
39 .long 1b,4b,2b,4b\n\
40 .previous" \
41 : "=&a" (oldval), "=&r" (ret), "=m" (*uaddr), \
42 "=&r" (tem) \
43 : "r" (oparg), "i" (-EFAULT), "m" (*uaddr), "1" (0))
45 static inline int
46 futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
47 {
48 int op = (encoded_op >> 28) & 7;
49 int cmp = (encoded_op >> 24) & 15;
50 int oparg = (encoded_op << 8) >> 20;
51 int cmparg = (encoded_op << 20) >> 20;
52 int oldval = 0, ret, tem;
53 if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
54 oparg = 1 << oparg;
56 if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
57 return -EFAULT;
59 inc_preempt_count();
61 if (op == FUTEX_OP_SET)
62 __futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg);
63 else {
64 #ifndef CONFIG_X86_BSWAP
65 if (boot_cpu_data.x86 == 3)
66 ret = -ENOSYS;
67 else
68 #endif
69 switch (op) {
70 case FUTEX_OP_ADD:
71 __futex_atomic_op1(LOCK "xaddl %0, %2", ret,
72 oldval, uaddr, oparg);
73 break;
74 case FUTEX_OP_OR:
75 __futex_atomic_op2("orl %4, %3", ret, oldval, uaddr,
76 oparg);
77 break;
78 case FUTEX_OP_ANDN:
79 __futex_atomic_op2("andl %4, %3", ret, oldval, uaddr,
80 ~oparg);
81 break;
82 case FUTEX_OP_XOR:
83 __futex_atomic_op2("xorl %4, %3", ret, oldval, uaddr,
84 oparg);
85 break;
86 default:
87 ret = -ENOSYS;
88 }
89 }
91 dec_preempt_count();
93 if (!ret) {
94 switch (cmp) {
95 case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
96 case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
97 case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
98 case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
99 case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
100 case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
101 default: ret = -ENOSYS;
102 }
103 }
104 return ret;
105 }
107 #endif
108 #endif