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7#ifndef __ASM_CMPXCHG_H
8#define __ASM_CMPXCHG_H
9
10#include <linux/types.h>
11
12extern void __xchg_called_with_bad_pointer(void);
13
14static inline unsigned long __xchg(unsigned long x, void *ptr, int size)
15{
16 unsigned long addr, old;
17 int shift;
18
19 switch (size) {
20 case 1:
21 addr = (unsigned long) ptr;
22 shift = (3 ^ (addr & 3)) << 3;
23 addr ^= addr & 3;
24 asm volatile(
25 " l %0,%4\n"
26 "0: lr 0,%0\n"
27 " nr 0,%3\n"
28 " or 0,%2\n"
29 " cs %0,0,%4\n"
30 " jl 0b\n"
31 : "=&d" (old), "=Q" (*(int *) addr)
32 : "d" (x << shift), "d" (~(255 << shift)),
33 "Q" (*(int *) addr) : "memory", "cc", "0");
34 return old >> shift;
35 case 2:
36 addr = (unsigned long) ptr;
37 shift = (2 ^ (addr & 2)) << 3;
38 addr ^= addr & 2;
39 asm volatile(
40 " l %0,%4\n"
41 "0: lr 0,%0\n"
42 " nr 0,%3\n"
43 " or 0,%2\n"
44 " cs %0,0,%4\n"
45 " jl 0b\n"
46 : "=&d" (old), "=Q" (*(int *) addr)
47 : "d" (x << shift), "d" (~(65535 << shift)),
48 "Q" (*(int *) addr) : "memory", "cc", "0");
49 return old >> shift;
50 case 4:
51 asm volatile(
52 " l %0,%3\n"
53 "0: cs %0,%2,%3\n"
54 " jl 0b\n"
55 : "=&d" (old), "=Q" (*(int *) ptr)
56 : "d" (x), "Q" (*(int *) ptr)
57 : "memory", "cc");
58 return old;
59#ifdef CONFIG_64BIT
60 case 8:
61 asm volatile(
62 " lg %0,%3\n"
63 "0: csg %0,%2,%3\n"
64 " jl 0b\n"
65 : "=&d" (old), "=m" (*(long *) ptr)
66 : "d" (x), "Q" (*(long *) ptr)
67 : "memory", "cc");
68 return old;
69#endif
70 }
71 __xchg_called_with_bad_pointer();
72 return x;
73}
74
75#define xchg(ptr, x) \
76({ \
77 __typeof__(*(ptr)) __ret; \
78 __ret = (__typeof__(*(ptr))) \
79 __xchg((unsigned long)(x), (void *)(ptr), sizeof(*(ptr)));\
80 __ret; \
81})
82
83
84
85
86
87
88
89#define __HAVE_ARCH_CMPXCHG
90
91extern void __cmpxchg_called_with_bad_pointer(void);
92
93static inline unsigned long __cmpxchg(void *ptr, unsigned long old,
94 unsigned long new, int size)
95{
96 unsigned long addr, prev, tmp;
97 int shift;
98
99 switch (size) {
100 case 1:
101 addr = (unsigned long) ptr;
102 shift = (3 ^ (addr & 3)) << 3;
103 addr ^= addr & 3;
104 asm volatile(
105 " l %0,%2\n"
106 "0: nr %0,%5\n"
107 " lr %1,%0\n"
108 " or %0,%3\n"
109 " or %1,%4\n"
110 " cs %0,%1,%2\n"
111 " jnl 1f\n"
112 " xr %1,%0\n"
113 " nr %1,%5\n"
114 " jnz 0b\n"
115 "1:"
116 : "=&d" (prev), "=&d" (tmp), "=Q" (*(int *) ptr)
117 : "d" (old << shift), "d" (new << shift),
118 "d" (~(255 << shift)), "Q" (*(int *) ptr)
119 : "memory", "cc");
120 return prev >> shift;
121 case 2:
122 addr = (unsigned long) ptr;
123 shift = (2 ^ (addr & 2)) << 3;
124 addr ^= addr & 2;
125 asm volatile(
126 " l %0,%2\n"
127 "0: nr %0,%5\n"
128 " lr %1,%0\n"
129 " or %0,%3\n"
130 " or %1,%4\n"
131 " cs %0,%1,%2\n"
132 " jnl 1f\n"
133 " xr %1,%0\n"
134 " nr %1,%5\n"
135 " jnz 0b\n"
136 "1:"
137 : "=&d" (prev), "=&d" (tmp), "=Q" (*(int *) ptr)
138 : "d" (old << shift), "d" (new << shift),
139 "d" (~(65535 << shift)), "Q" (*(int *) ptr)
140 : "memory", "cc");
141 return prev >> shift;
142 case 4:
143 asm volatile(
144 " cs %0,%3,%1\n"
145 : "=&d" (prev), "=Q" (*(int *) ptr)
146 : "0" (old), "d" (new), "Q" (*(int *) ptr)
147 : "memory", "cc");
148 return prev;
149#ifdef CONFIG_64BIT
150 case 8:
151 asm volatile(
152 " csg %0,%3,%1\n"
153 : "=&d" (prev), "=Q" (*(long *) ptr)
154 : "0" (old), "d" (new), "Q" (*(long *) ptr)
155 : "memory", "cc");
156 return prev;
157#endif
158 }
159 __cmpxchg_called_with_bad_pointer();
160 return old;
161}
162
163#define cmpxchg(ptr, o, n) \
164 ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
165 (unsigned long)(n), sizeof(*(ptr))))
166
167#ifdef CONFIG_64BIT
168#define cmpxchg64(ptr, o, n) \
169({ \
170 cmpxchg((ptr), (o), (n)); \
171})
172#else
173static inline unsigned long long __cmpxchg64(void *ptr,
174 unsigned long long old,
175 unsigned long long new)
176{
177 register_pair rp_old = {.pair = old};
178 register_pair rp_new = {.pair = new};
179
180 asm volatile(
181 " cds %0,%2,%1"
182 : "+&d" (rp_old), "=Q" (ptr)
183 : "d" (rp_new), "Q" (ptr)
184 : "cc");
185 return rp_old.pair;
186}
187#define cmpxchg64(ptr, o, n) \
188 ((__typeof__(*(ptr)))__cmpxchg64((ptr), \
189 (unsigned long long)(o), \
190 (unsigned long long)(n)))
191#endif
192
193#include <asm-generic/cmpxchg-local.h>
194
195static inline unsigned long __cmpxchg_local(void *ptr,
196 unsigned long old,
197 unsigned long new, int size)
198{
199 switch (size) {
200 case 1:
201 case 2:
202 case 4:
203#ifdef CONFIG_64BIT
204 case 8:
205#endif
206 return __cmpxchg(ptr, old, new, size);
207 default:
208 return __cmpxchg_local_generic(ptr, old, new, size);
209 }
210
211 return old;
212}
213
214
215
216
217
218#define cmpxchg_local(ptr, o, n) \
219 ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
220 (unsigned long)(n), sizeof(*(ptr))))
221
222#define cmpxchg64_local(ptr, o, n) cmpxchg64((ptr), (o), (n))
223
224#endif
225
