summaryrefslogtreecommitdiff
path: root/arch/x86/include/asm/atomic64_32.h
blob: 46e1ef17d92d01f3ee5336f012cf1ae63b12e8cf (plain)
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
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_ATOMIC64_32_H
#define _ASM_X86_ATOMIC64_32_H

#include <linux/compiler.h>
#include <linux/types.h>
//#include <asm/cmpxchg.h>

/* An 64bit atomic type */

typedef struct {
	u64 __aligned(8) counter;
} atomic64_t;

#define ATOMIC64_INIT(val)	{ (val) }

#define __ATOMIC64_DECL(sym) void atomic64_##sym(atomic64_t *, ...)
#ifndef ATOMIC64_EXPORT
#define ATOMIC64_DECL_ONE __ATOMIC64_DECL
#else
#define ATOMIC64_DECL_ONE(sym) __ATOMIC64_DECL(sym); \
	ATOMIC64_EXPORT(atomic64_##sym)
#endif

#ifdef CONFIG_X86_CMPXCHG64
#define __alternative_atomic64(f, g, out, in...) \
	asm volatile("call %P[func]" \
		     : out : [func] "i" (atomic64_##g##_cx8), ## in)

#define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8)
#else
#define __alternative_atomic64(f, g, out, in...) \
	alternative_call(atomic64_##f##_386, atomic64_##g##_cx8, \
			 X86_FEATURE_CX8, ASM_OUTPUT2(out), ## in)

#define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8); \
	ATOMIC64_DECL_ONE(sym##_386)

ATOMIC64_DECL_ONE(add_386);
ATOMIC64_DECL_ONE(sub_386);
ATOMIC64_DECL_ONE(inc_386);
ATOMIC64_DECL_ONE(dec_386);
#endif

#define alternative_atomic64(f, out, in...) \
	__alternative_atomic64(f, f, ASM_OUTPUT2(out), ## in)

ATOMIC64_DECL(read);
ATOMIC64_DECL(set);
ATOMIC64_DECL(xchg);
ATOMIC64_DECL(add_return);
ATOMIC64_DECL(sub_return);
ATOMIC64_DECL(inc_return);
ATOMIC64_DECL(dec_return);
ATOMIC64_DECL(dec_if_positive);
ATOMIC64_DECL(inc_not_zero);
ATOMIC64_DECL(add_unless);

#undef ATOMIC64_DECL
#undef ATOMIC64_DECL_ONE
#undef __ATOMIC64_DECL
#undef ATOMIC64_EXPORT

/**
 * arch_atomic64_cmpxchg - cmpxchg atomic64 variable
 * @v: pointer to type atomic64_t
 * @o: expected value
 * @n: new value
 *
 * Atomically sets @v to @n if it was equal to @o and returns
 * the old value.
 */

static inline long long arch_atomic64_cmpxchg(atomic64_t *v, long long o,
					      long long n)
{
	return arch_cmpxchg64(&v->counter, o, n);
}

/**
 * arch_atomic64_xchg - xchg atomic64 variable
 * @v: pointer to type atomic64_t
 * @n: value to assign
 *
 * Atomically xchgs the value of @v to @n and returns
 * the old value.
 */
static inline long long arch_atomic64_xchg(atomic64_t *v, long long n)
{
	long long o;
	unsigned high = (unsigned)(n >> 32);
	unsigned low = (unsigned)n;
	alternative_atomic64(xchg, "=&A" (o),
			     "S" (v), "b" (low), "c" (high)
			     : "memory");
	return o;
}

/**
 * arch_atomic64_set - set atomic64 variable
 * @v: pointer to type atomic64_t
 * @i: value to assign
 *
 * Atomically sets the value of @v to @n.
 */
static inline void arch_atomic64_set(atomic64_t *v, long long i)
{
	unsigned high = (unsigned)(i >> 32);
	unsigned low = (unsigned)i;
	alternative_atomic64(set, /* no output */,
			     "S" (v), "b" (low), "c" (high)
			     : "eax", "edx", "memory");
}

/**
 * arch_atomic64_read - read atomic64 variable
 * @v: pointer to type atomic64_t
 *
 * Atomically reads the value of @v and returns it.
 */
static inline long long arch_atomic64_read(const atomic64_t *v)
{
	long long r;
	alternative_atomic64(read, "=&A" (r), "c" (v) : "memory");
	return r;
 }

/**
 * arch_atomic64_add_return - add and return
 * @i: integer value to add
 * @v: pointer to type atomic64_t
 *
 * Atomically adds @i to @v and returns @i + *@v
 */
static inline long long arch_atomic64_add_return(long long i, atomic64_t *v)
{
	alternative_atomic64(add_return,
			     ASM_OUTPUT2("+A" (i), "+c" (v)),
			     ASM_NO_INPUT_CLOBBER("memory"));
	return i;
}

/*
 * Other variants with different arithmetic operators:
 */
static inline long long arch_atomic64_sub_return(long long i, atomic64_t *v)
{
	alternative_atomic64(sub_return,
			     ASM_OUTPUT2("+A" (i), "+c" (v)),
			     ASM_NO_INPUT_CLOBBER("memory"));
	return i;
}

static inline long long arch_atomic64_inc_return(atomic64_t *v)
{
	long long a;
	alternative_atomic64(inc_return, "=&A" (a),
			     "S" (v) : "memory", "ecx");
	return a;
}

static inline long long arch_atomic64_dec_return(atomic64_t *v)
{
	long long a;
	alternative_atomic64(dec_return, "=&A" (a),
			     "S" (v) : "memory", "ecx");
	return a;
}

/**
 * arch_atomic64_add - add integer to atomic64 variable
 * @i: integer value to add
 * @v: pointer to type atomic64_t
 *
 * Atomically adds @i to @v.
 */
static inline long long arch_atomic64_add(long long i, atomic64_t *v)
{
	__alternative_atomic64(add, add_return,
			       ASM_OUTPUT2("+A" (i), "+c" (v)),
			       ASM_NO_INPUT_CLOBBER("memory"));
	return i;
}

/**
 * arch_atomic64_sub - subtract the atomic64 variable
 * @i: integer value to subtract
 * @v: pointer to type atomic64_t
 *
 * Atomically subtracts @i from @v.
 */
static inline long long arch_atomic64_sub(long long i, atomic64_t *v)
{
	__alternative_atomic64(sub, sub_return,
			       ASM_OUTPUT2("+A" (i), "+c" (v)),
			       ASM_NO_INPUT_CLOBBER("memory"));
	return i;
}

/**
 * arch_atomic64_sub_and_test - subtract value from variable and test result
 * @i: integer value to subtract
 * @v: pointer to type atomic64_t
 *
 * Atomically subtracts @i from @v and returns
 * true if the result is zero, or false for all
 * other cases.
 */
static inline int arch_atomic64_sub_and_test(long long i, atomic64_t *v)
{
	return arch_atomic64_sub_return(i, v) == 0;
}

/**
 * arch_atomic64_inc - increment atomic64 variable
 * @v: pointer to type atomic64_t
 *
 * Atomically increments @v by 1.
 */
static inline void arch_atomic64_inc(atomic64_t *v)
{
	__alternative_atomic64(inc, inc_return, /* no output */,
			       "S" (v) : "memory", "eax", "ecx", "edx");
}

/**
 * arch_atomic64_dec - decrement atomic64 variable
 * @v: pointer to type atomic64_t
 *
 * Atomically decrements @v by 1.
 */
static inline void arch_atomic64_dec(atomic64_t *v)
{
	__alternative_atomic64(dec, dec_return, /* no output */,
			       "S" (v) : "memory", "eax", "ecx", "edx");
}

/**
 * arch_atomic64_dec_and_test - decrement and test
 * @v: pointer to type atomic64_t
 *
 * Atomically decrements @v by 1 and
 * returns true if the result is 0, or false for all other
 * cases.
 */
static inline int arch_atomic64_dec_and_test(atomic64_t *v)
{
	return arch_atomic64_dec_return(v) == 0;
}

/**
 * atomic64_inc_and_test - increment and test
 * @v: pointer to type atomic64_t
 *
 * Atomically increments @v by 1
 * and returns true if the result is zero, or false for all
 * other cases.
 */
static inline int arch_atomic64_inc_and_test(atomic64_t *v)
{
	return arch_atomic64_inc_return(v) == 0;
}

/**
 * arch_atomic64_add_negative - add and test if negative
 * @i: integer value to add
 * @v: pointer to type atomic64_t
 *
 * Atomically adds @i to @v and returns true
 * if the result is negative, or false when
 * result is greater than or equal to zero.
 */
static inline int arch_atomic64_add_negative(long long i, atomic64_t *v)
{
	return arch_atomic64_add_return(i, v) < 0;
}

/**
 * arch_atomic64_add_unless - add unless the number is a given value
 * @v: pointer of type atomic64_t
 * @a: the amount to add to v...
 * @u: ...unless v is equal to u.
 *
 * Atomically adds @a to @v, so long as it was not @u.
 * Returns non-zero if the add was done, zero otherwise.
 */
static inline int arch_atomic64_add_unless(atomic64_t *v, long long a,
					   long long u)
{
	unsigned low = (unsigned)u;
	unsigned high = (unsigned)(u >> 32);
	alternative_atomic64(add_unless,
			     ASM_OUTPUT2("+A" (a), "+c" (low), "+D" (high)),
			     "S" (v) : "memory");
	return (int)a;
}


static inline int arch_atomic64_inc_not_zero(atomic64_t *v)
{
	int r;
	alternative_atomic64(inc_not_zero, "=&a" (r),
			     "S" (v) : "ecx", "edx", "memory");
	return r;
}

static inline long long arch_atomic64_dec_if_positive(atomic64_t *v)
{
	long long r;
	alternative_atomic64(dec_if_positive, "=&A" (r),
			     "S" (v) : "ecx", "memory");
	return r;
}

#undef alternative_atomic64
#undef __alternative_atomic64

static inline void arch_atomic64_and(long long i, atomic64_t *v)
{
	long long old, c = 0;

	while ((old = arch_atomic64_cmpxchg(v, c, c & i)) != c)
		c = old;
}

static inline long long arch_atomic64_fetch_and(long long i, atomic64_t *v)
{
	long long old, c = 0;

	while ((old = arch_atomic64_cmpxchg(v, c, c & i)) != c)
		c = old;

	return old;
}

static inline void arch_atomic64_or(long long i, atomic64_t *v)
{
	long long old, c = 0;

	while ((old = arch_atomic64_cmpxchg(v, c, c | i)) != c)
		c = old;
}

static inline long long arch_atomic64_fetch_or(long long i, atomic64_t *v)
{
	long long old, c = 0;

	while ((old = arch_atomic64_cmpxchg(v, c, c | i)) != c)
		c = old;

	return old;
}

static inline void arch_atomic64_xor(long long i, atomic64_t *v)
{
	long long old, c = 0;

	while ((old = arch_atomic64_cmpxchg(v, c, c ^ i)) != c)
		c = old;
}

static inline long long arch_atomic64_fetch_xor(long long i, atomic64_t *v)
{
	long long old, c = 0;

	while ((old = arch_atomic64_cmpxchg(v, c, c ^ i)) != c)
		c = old;

	return old;
}

static inline long long arch_atomic64_fetch_add(long long i, atomic64_t *v)
{
	long long old, c = 0;

	while ((old = arch_atomic64_cmpxchg(v, c, c + i)) != c)
		c = old;

	return old;
}

#define arch_atomic64_fetch_sub(i, v)	arch_atomic64_fetch_add(-(i), (v))

#endif /* _ASM_X86_ATOMIC64_32_H */