1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
|
/*
* Copyright IBM Corp. 1999, 2011
*
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
*/
#ifndef __ASM_CMPXCHG_H
#define __ASM_CMPXCHG_H
#include <linux/types.h>
extern void __xchg_called_with_bad_pointer(void);
static inline unsigned long __xchg(unsigned long x, void *ptr, int size)
{
unsigned long addr, old;
int shift;
switch (size) {
case 1:
addr = (unsigned long) ptr;
shift = (3 ^ (addr & 3)) << 3;
addr ^= addr & 3;
asm volatile(
" l %0,%4\n"
"0: lr 0,%0\n"
" nr 0,%3\n"
" or 0,%2\n"
" cs %0,0,%4\n"
" jl 0b\n"
: "=&d" (old), "=Q" (*(int *) addr)
: "d" (x << shift), "d" (~(255 << shift)),
"Q" (*(int *) addr) : "memory", "cc", "0");
return old >> shift;
case 2:
addr = (unsigned long) ptr;
shift = (2 ^ (addr & 2)) << 3;
addr ^= addr & 2;
asm volatile(
" l %0,%4\n"
"0: lr 0,%0\n"
" nr 0,%3\n"
" or 0,%2\n"
" cs %0,0,%4\n"
" jl 0b\n"
: "=&d" (old), "=Q" (*(int *) addr)
: "d" (x << shift), "d" (~(65535 << shift)),
"Q" (*(int *) addr) : "memory", "cc", "0");
return old >> shift;
case 4:
asm volatile(
" l %0,%3\n"
"0: cs %0,%2,%3\n"
" jl 0b\n"
: "=&d" (old), "=Q" (*(int *) ptr)
: "d" (x), "Q" (*(int *) ptr)
: "memory", "cc");
return old;
#ifdef CONFIG_64BIT
case 8:
asm volatile(
" lg %0,%3\n"
"0: csg %0,%2,%3\n"
" jl 0b\n"
: "=&d" (old), "=m" (*(long *) ptr)
: "d" (x), "Q" (*(long *) ptr)
: "memory", "cc");
return old;
#endif /* CONFIG_64BIT */
}
__xchg_called_with_bad_pointer();
return x;
}
#define xchg(ptr, x) \
({ \
__typeof__(*(ptr)) __ret; \
__ret = (__typeof__(*(ptr))) \
__xchg((unsigned long)(x), (void *)(ptr), sizeof(*(ptr)));\
__ret; \
})
/*
* Atomic compare and exchange. Compare OLD with MEM, if identical,
* store NEW in MEM. Return the initial value in MEM. Success is
* indicated by comparing RETURN with OLD.
*/
#define __HAVE_ARCH_CMPXCHG
extern void __cmpxchg_called_with_bad_pointer(void);
static inline unsigned long __cmpxchg(void *ptr, unsigned long old,
unsigned long new, int size)
{
unsigned long addr, prev, tmp;
int shift;
switch (size) {
case 1:
addr = (unsigned long) ptr;
shift = (3 ^ (addr & 3)) << 3;
addr ^= addr & 3;
asm volatile(
" l %0,%2\n"
"0: nr %0,%5\n"
" lr %1,%0\n"
" or %0,%3\n"
" or %1,%4\n"
" cs %0,%1,%2\n"
" jnl 1f\n"
" xr %1,%0\n"
" nr %1,%5\n"
" jnz 0b\n"
"1:"
: "=&d" (prev), "=&d" (tmp), "=Q" (*(int *) ptr)
: "d" (old << shift), "d" (new << shift),
"d" (~(255 << shift)), "Q" (*(int *) ptr)
: "memory", "cc");
return prev >> shift;
case 2:
addr = (unsigned long) ptr;
shift = (2 ^ (addr & 2)) << 3;
addr ^= addr & 2;
asm volatile(
" l %0,%2\n"
"0: nr %0,%5\n"
" lr %1,%0\n"
" or %0,%3\n"
" or %1,%4\n"
" cs %0,%1,%2\n"
" jnl 1f\n"
" xr %1,%0\n"
" nr %1,%5\n"
" jnz 0b\n"
"1:"
: "=&d" (prev), "=&d" (tmp), "=Q" (*(int *) ptr)
: "d" (old << shift), "d" (new << shift),
"d" (~(65535 << shift)), "Q" (*(int *) ptr)
: "memory", "cc");
return prev >> shift;
case 4:
asm volatile(
" cs %0,%3,%1\n"
: "=&d" (prev), "=Q" (*(int *) ptr)
: "0" (old), "d" (new), "Q" (*(int *) ptr)
: "memory", "cc");
return prev;
#ifdef CONFIG_64BIT
case 8:
asm volatile(
" csg %0,%3,%1\n"
: "=&d" (prev), "=Q" (*(long *) ptr)
: "0" (old), "d" (new), "Q" (*(long *) ptr)
: "memory", "cc");
return prev;
#endif /* CONFIG_64BIT */
}
__cmpxchg_called_with_bad_pointer();
return old;
}
#define cmpxchg(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#ifdef CONFIG_64BIT
#define cmpxchg64(ptr, o, n) \
({ \
BUILD_BUG_ON(sizeof(*(ptr)) != 8); \
cmpxchg((ptr), (o), (n)); \
})
#else /* CONFIG_64BIT */
static inline unsigned long long __cmpxchg64(void *ptr,
unsigned long long old,
unsigned long long new)
{
register_pair rp_old = {.pair = old};
register_pair rp_new = {.pair = new};
asm volatile(
" cds %0,%2,%1"
: "+&d" (rp_old), "=Q" (ptr)
: "d" (rp_new), "Q" (ptr)
: "cc");
return rp_old.pair;
}
#define cmpxchg64(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg64((ptr), \
(unsigned long long)(o), \
(unsigned long long)(n)))
#endif /* CONFIG_64BIT */
#include <asm-generic/cmpxchg-local.h>
static inline unsigned long __cmpxchg_local(void *ptr,
unsigned long old,
unsigned long new, int size)
{
switch (size) {
case 1:
case 2:
case 4:
#ifdef CONFIG_64BIT
case 8:
#endif
return __cmpxchg(ptr, old, new, size);
default:
return __cmpxchg_local_generic(ptr, old, new, size);
}
return old;
}
/*
* cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
* them available.
*/
#define cmpxchg_local(ptr, o, n) \
((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))))
#define cmpxchg64_local(ptr, o, n) cmpxchg64((ptr), (o), (n))
#endif /* __ASM_CMPXCHG_H */
|
