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authorHeiko Carstens <heiko.carstens@de.ibm.com>2011-03-23 05:16:05 -0400
committerMartin Schwidefsky <sky@mschwide.boeblingen.de.ibm.com>2011-03-23 05:15:59 -0400
commita2c9dbe8dbb8591ae6fd142e562813cd95d06609 (patch)
tree70cdf19845059a80072328c6125315f39b3e26f1 /arch/s390/include/asm/cmpxchg.h
parent3c190c51f55eab691e5d096747262d2653e67de1 (diff)
[S390] xchg/cmpxchg: move to own header file
Move xchg() and cmpxchg() functions to own header file like some other architectures have done. With this we make sure that system.h now really looks like a place where everything is gathered that doesn't fit anywhere else. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/include/asm/cmpxchg.h')
-rw-r--r--arch/s390/include/asm/cmpxchg.h205
1 files changed, 205 insertions, 0 deletions
diff --git a/arch/s390/include/asm/cmpxchg.h b/arch/s390/include/asm/cmpxchg.h
new file mode 100644
index 000000000000..4052df9030cb
--- /dev/null
+++ b/arch/s390/include/asm/cmpxchg.h
@@ -0,0 +1,205 @@
1/*
2 * Copyright IBM Corp. 1999, 2011
3 *
4 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
5 */
6
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 /* CONFIG_64BIT */
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 * Atomic compare and exchange. Compare OLD with MEM, if identical,
85 * store NEW in MEM. Return the initial value in MEM. Success is
86 * indicated by comparing RETURN with OLD.
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 /* CONFIG_64BIT */
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#include <asm-generic/cmpxchg-local.h>
168
169static inline unsigned long __cmpxchg_local(void *ptr,
170 unsigned long old,
171 unsigned long new, int size)
172{
173 switch (size) {
174 case 1:
175 case 2:
176 case 4:
177#ifdef CONFIG_64BIT
178 case 8:
179#endif
180 return __cmpxchg(ptr, old, new, size);
181 default:
182 return __cmpxchg_local_generic(ptr, old, new, size);
183 }
184
185 return old;
186}
187
188/*
189 * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
190 * them available.
191 */
192#define cmpxchg_local(ptr, o, n) \
193 ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
194 (unsigned long)(n), sizeof(*(ptr))))
195#ifdef CONFIG_64BIT
196#define cmpxchg64_local(ptr, o, n) \
197({ \
198 BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
199 cmpxchg_local((ptr), (o), (n)); \
200})
201#else
202#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
203#endif
204
205#endif /* __ASM_CMPXCHG_H */