1 #ifndef _ASM_FUTEX_H
2 #define _ASM_FUTEX_H
3
4 #include <linux/futex.h>
5 #include <linux/uaccess.h>
6 #include <asm/errno.h>
7
8 #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \
9 do { \
10 register unsigned long r8 __asm ("r8") = 0; \
11 __asm__ __volatile__( \
12 " mf;; \n" \
13 "[1:] " insn ";; \n" \
14 " .xdata4 \"__ex_table\", 1b-., 2f-. \n" \
15 "[2:]" \
16 : "+r" (r8), "=r" (oldval) \
17 : "r" (uaddr), "r" (oparg) \
18 : "memory"); \
19 ret = r8; \
20 } while (0)
21
22 #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \
23 do { \
24 register unsigned long r8 __asm ("r8") = 0; \
25 int val, newval; \
26 do { \
27 __asm__ __volatile__( \
28 " mf;; \n" \
29 "[1:] ld4 %3=[%4];; \n" \
30 " mov %2=%3 \n" \
31 insn ";; \n" \
32 " mov ar.ccv=%2;; \n" \
33 "[2:] cmpxchg4.acq %1=[%4],%3,ar.ccv;; \n" \
34 " .xdata4 \"__ex_table\", 1b-., 3f-.\n" \
35 " .xdata4 \"__ex_table\", 2b-., 3f-.\n" \
36 "[3:]" \
37 : "+r" (r8), "=r" (val), "=&r" (oldval), \
38 "=&r" (newval) \
39 : "r" (uaddr), "r" (oparg) \
40 : "memory"); \
41 if (unlikely (r8)) \
42 break; \
43 } while (unlikely (val != oldval)); \
44 ret = r8; \
45 } while (0)
46
47 static inline int
arch_futex_atomic_op_inuser(int op,int oparg,int * oval,u32 __user * uaddr)48 arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
49 {
50 int oldval = 0, ret;
51
52 pagefault_disable();
53
54 switch (op) {
55 case FUTEX_OP_SET:
56 __futex_atomic_op1("xchg4 %1=[%2],%3", ret, oldval, uaddr,
57 oparg);
58 break;
59 case FUTEX_OP_ADD:
60 __futex_atomic_op2("add %3=%3,%5", ret, oldval, uaddr, oparg);
61 break;
62 case FUTEX_OP_OR:
63 __futex_atomic_op2("or %3=%3,%5", ret, oldval, uaddr, oparg);
64 break;
65 case FUTEX_OP_ANDN:
66 __futex_atomic_op2("and %3=%3,%5", ret, oldval, uaddr,
67 ~oparg);
68 break;
69 case FUTEX_OP_XOR:
70 __futex_atomic_op2("xor %3=%3,%5", ret, oldval, uaddr, oparg);
71 break;
72 default:
73 ret = -ENOSYS;
74 }
75
76 pagefault_enable();
77
78 if (!ret)
79 *oval = oldval;
80
81 return ret;
82 }
83
84 static inline int
futex_atomic_cmpxchg_inatomic(u32 * uval,u32 __user * uaddr,u32 oldval,u32 newval)85 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr,
86 u32 oldval, u32 newval)
87 {
88 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32)))
89 return -EFAULT;
90
91 {
92 register unsigned long r8 __asm ("r8") = 0;
93 unsigned long prev;
94 __asm__ __volatile__(
95 " mf;; \n"
96 " mov ar.ccv=%4;; \n"
97 "[1:] cmpxchg4.acq %1=[%2],%3,ar.ccv \n"
98 " .xdata4 \"__ex_table\", 1b-., 2f-. \n"
99 "[2:]"
100 : "+r" (r8), "=&r" (prev)
101 : "r" (uaddr), "r" (newval),
102 "rO" ((long) (unsigned) oldval)
103 : "memory");
104 *uval = prev;
105 return r8;
106 }
107 }
108
109 #endif /* _ASM_FUTEX_H */
110