1 #ifndef _ASM_X86_FUTEX_H
2 #define _ASM_X86_FUTEX_H
6 #include <linux/futex.h>
7 #include <linux/uaccess.h>
10 #include <asm/errno.h>
11 #include <asm/processor.h>
13 #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \
14 asm volatile("1:\t" insn "\n" \
15 "2:\t.section .fixup,\"ax\"\n" \
19 _ASM_EXTABLE(1b, 3b) \
20 : "=r" (oldval), "=r" (ret), "+m" (*uaddr) \
21 : "i" (-EFAULT), "0" (oparg), "1" (0))
23 #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \
24 asm volatile("1:\tmovl %2, %0\n" \
27 "2:\t" LOCK_PREFIX "cmpxchgl %3, %2\n" \
29 "3:\t.section .fixup,\"ax\"\n" \
33 _ASM_EXTABLE(1b, 4b) \
34 _ASM_EXTABLE(2b, 4b) \
35 : "=&a" (oldval), "=&r" (ret), \
36 "+m" (*uaddr), "=&r" (tem) \
37 : "r" (oparg), "i" (-EFAULT), "1" (0))
39 static inline int futex_atomic_op_inuser(int encoded_op, u32 __user *uaddr)
41 int op = (encoded_op >> 28) & 7;
42 int cmp = (encoded_op >> 24) & 15;
43 int oparg = (encoded_op << 8) >> 20;
44 int cmparg = (encoded_op << 20) >> 20;
45 int oldval = 0, ret, tem;
47 if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
50 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
53 #if defined(CONFIG_X86_32) && !defined(CONFIG_X86_BSWAP)
54 /* Real i386 machines can only support FUTEX_OP_SET */
55 if (op != FUTEX_OP_SET && boot_cpu_data.x86 == 3)
63 __futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg);
66 __futex_atomic_op1(LOCK_PREFIX "xaddl %0, %2", ret, oldval,
70 __futex_atomic_op2("orl %4, %3", ret, oldval, uaddr, oparg);
73 __futex_atomic_op2("andl %4, %3", ret, oldval, uaddr, ~oparg);
76 __futex_atomic_op2("xorl %4, %3", ret, oldval, uaddr, oparg);
87 ret = (oldval == cmparg);
90 ret = (oldval != cmparg);
93 ret = (oldval < cmparg);
96 ret = (oldval >= cmparg);
99 ret = (oldval <= cmparg);
101 case FUTEX_OP_CMP_GT:
102 ret = (oldval > cmparg);
111 static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
112 u32 oldval, u32 newval)
116 #if defined(CONFIG_X86_32) && !defined(CONFIG_X86_BSWAP)
117 /* Real i386 machines have no cmpxchg instruction */
118 if (boot_cpu_data.x86 == 3)
122 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
125 asm volatile("1:\t" LOCK_PREFIX "cmpxchgl %4, %2\n"
126 "2:\t.section .fixup, \"ax\"\n"
131 : "+r" (ret), "=a" (oldval), "+m" (*uaddr)
132 : "i" (-EFAULT), "r" (newval), "1" (oldval)
141 #endif /* _ASM_X86_FUTEX_H */