1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_CMPXCHG_H_
3 #define _ASM_POWERPC_CMPXCHG_H_
4 
5 #ifdef __KERNEL__
6 #include <linux/compiler.h>
7 #include <asm/synch.h>
8 #include <linux/bug.h>
9 
10 #ifdef __BIG_ENDIAN
11 #define BITOFF_CAL(size, off)	((sizeof(u32) - size - off) * BITS_PER_BYTE)
12 #else
13 #define BITOFF_CAL(size, off)	(off * BITS_PER_BYTE)
14 #endif
15 
16 #define XCHG_GEN(type, sfx, cl)				\
17 static inline u32 __xchg_##type##sfx(volatile void *p, u32 val)	\
18 {								\
19 	unsigned int prev, prev_mask, tmp, bitoff, off;		\
20 								\
21 	off = (unsigned long)p % sizeof(u32);			\
22 	bitoff = BITOFF_CAL(sizeof(type), off);			\
23 	p -= off;						\
24 	val <<= bitoff;						\
25 	prev_mask = (u32)(type)-1 << bitoff;			\
26 								\
27 	__asm__ __volatile__(					\
28 "1:	lwarx   %0,0,%3\n"					\
29 "	andc	%1,%0,%5\n"					\
30 "	or	%1,%1,%4\n"					\
31 "	stwcx.	%1,0,%3\n"					\
32 "	bne-	1b\n"						\
33 	: "=&r" (prev), "=&r" (tmp), "+m" (*(u32*)p)		\
34 	: "r" (p), "r" (val), "r" (prev_mask)			\
35 	: "cc", cl);						\
36 								\
37 	return prev >> bitoff;					\
38 }
39 
40 #define CMPXCHG_GEN(type, sfx, br, br2, cl)			\
41 static inline							\
42 u32 __cmpxchg_##type##sfx(volatile void *p, u32 old, u32 new)	\
43 {								\
44 	unsigned int prev, prev_mask, tmp, bitoff, off;		\
45 								\
46 	off = (unsigned long)p % sizeof(u32);			\
47 	bitoff = BITOFF_CAL(sizeof(type), off);			\
48 	p -= off;						\
49 	old <<= bitoff;						\
50 	new <<= bitoff;						\
51 	prev_mask = (u32)(type)-1 << bitoff;			\
52 								\
53 	__asm__ __volatile__(					\
54 	br							\
55 "1:	lwarx   %0,0,%3\n"					\
56 "	and	%1,%0,%6\n"					\
57 "	cmpw	0,%1,%4\n"					\
58 "	bne-	2f\n"						\
59 "	andc	%1,%0,%6\n"					\
60 "	or	%1,%1,%5\n"					\
61 "	stwcx.  %1,0,%3\n"					\
62 "	bne-    1b\n"						\
63 	br2							\
64 	"\n"							\
65 "2:"								\
66 	: "=&r" (prev), "=&r" (tmp), "+m" (*(u32*)p)		\
67 	: "r" (p), "r" (old), "r" (new), "r" (prev_mask)	\
68 	: "cc", cl);						\
69 								\
70 	return prev >> bitoff;					\
71 }
72 
73 /*
74  * Atomic exchange
75  *
76  * Changes the memory location '*p' to be val and returns
77  * the previous value stored there.
78  */
79 
80 #ifndef CONFIG_PPC_HAS_LBARX_LHARX
81 XCHG_GEN(u8, _local, "memory");
82 XCHG_GEN(u8, _relaxed, "cc");
83 XCHG_GEN(u16, _local, "memory");
84 XCHG_GEN(u16, _relaxed, "cc");
85 #else
86 static __always_inline unsigned long
__xchg_u8_local(volatile void * p,unsigned long val)87 __xchg_u8_local(volatile void *p, unsigned long val)
88 {
89 	unsigned long prev;
90 
91 	__asm__ __volatile__(
92 "1:	lbarx	%0,0,%2		# __xchg_u8_local\n"
93 "	stbcx.	%3,0,%2 \n"
94 "	bne-	1b"
95 	: "=&r" (prev), "+m" (*(volatile unsigned char *)p)
96 	: "r" (p), "r" (val)
97 	: "cc", "memory");
98 
99 	return prev;
100 }
101 
102 static __always_inline unsigned long
__xchg_u8_relaxed(u8 * p,unsigned long val)103 __xchg_u8_relaxed(u8 *p, unsigned long val)
104 {
105 	unsigned long prev;
106 
107 	__asm__ __volatile__(
108 "1:	lbarx	%0,0,%2		# __xchg_u8_relaxed\n"
109 "	stbcx.	%3,0,%2\n"
110 "	bne-	1b"
111 	: "=&r" (prev), "+m" (*p)
112 	: "r" (p), "r" (val)
113 	: "cc");
114 
115 	return prev;
116 }
117 
118 static __always_inline unsigned long
__xchg_u16_local(volatile void * p,unsigned long val)119 __xchg_u16_local(volatile void *p, unsigned long val)
120 {
121 	unsigned long prev;
122 
123 	__asm__ __volatile__(
124 "1:	lharx	%0,0,%2		# __xchg_u16_local\n"
125 "	sthcx.	%3,0,%2\n"
126 "	bne-	1b"
127 	: "=&r" (prev), "+m" (*(volatile unsigned short *)p)
128 	: "r" (p), "r" (val)
129 	: "cc", "memory");
130 
131 	return prev;
132 }
133 
134 static __always_inline unsigned long
__xchg_u16_relaxed(u16 * p,unsigned long val)135 __xchg_u16_relaxed(u16 *p, unsigned long val)
136 {
137 	unsigned long prev;
138 
139 	__asm__ __volatile__(
140 "1:	lharx	%0,0,%2		# __xchg_u16_relaxed\n"
141 "	sthcx.	%3,0,%2\n"
142 "	bne-	1b"
143 	: "=&r" (prev), "+m" (*p)
144 	: "r" (p), "r" (val)
145 	: "cc");
146 
147 	return prev;
148 }
149 #endif
150 
151 static __always_inline unsigned long
__xchg_u32_local(volatile void * p,unsigned long val)152 __xchg_u32_local(volatile void *p, unsigned long val)
153 {
154 	unsigned long prev;
155 
156 	__asm__ __volatile__(
157 "1:	lwarx	%0,0,%2 \n"
158 "	stwcx.	%3,0,%2 \n\
159 	bne-	1b"
160 	: "=&r" (prev), "+m" (*(volatile unsigned int *)p)
161 	: "r" (p), "r" (val)
162 	: "cc", "memory");
163 
164 	return prev;
165 }
166 
167 static __always_inline unsigned long
__xchg_u32_relaxed(u32 * p,unsigned long val)168 __xchg_u32_relaxed(u32 *p, unsigned long val)
169 {
170 	unsigned long prev;
171 
172 	__asm__ __volatile__(
173 "1:	lwarx	%0,0,%2\n"
174 "	stwcx.	%3,0,%2\n"
175 "	bne-	1b"
176 	: "=&r" (prev), "+m" (*p)
177 	: "r" (p), "r" (val)
178 	: "cc");
179 
180 	return prev;
181 }
182 
183 #ifdef CONFIG_PPC64
184 static __always_inline unsigned long
__xchg_u64_local(volatile void * p,unsigned long val)185 __xchg_u64_local(volatile void *p, unsigned long val)
186 {
187 	unsigned long prev;
188 
189 	__asm__ __volatile__(
190 "1:	ldarx	%0,0,%2 \n"
191 "	stdcx.	%3,0,%2 \n\
192 	bne-	1b"
193 	: "=&r" (prev), "+m" (*(volatile unsigned long *)p)
194 	: "r" (p), "r" (val)
195 	: "cc", "memory");
196 
197 	return prev;
198 }
199 
200 static __always_inline unsigned long
__xchg_u64_relaxed(u64 * p,unsigned long val)201 __xchg_u64_relaxed(u64 *p, unsigned long val)
202 {
203 	unsigned long prev;
204 
205 	__asm__ __volatile__(
206 "1:	ldarx	%0,0,%2\n"
207 "	stdcx.	%3,0,%2\n"
208 "	bne-	1b"
209 	: "=&r" (prev), "+m" (*p)
210 	: "r" (p), "r" (val)
211 	: "cc");
212 
213 	return prev;
214 }
215 #endif
216 
217 static __always_inline unsigned long
__xchg_local(void * ptr,unsigned long x,unsigned int size)218 __xchg_local(void *ptr, unsigned long x, unsigned int size)
219 {
220 	switch (size) {
221 	case 1:
222 		return __xchg_u8_local(ptr, x);
223 	case 2:
224 		return __xchg_u16_local(ptr, x);
225 	case 4:
226 		return __xchg_u32_local(ptr, x);
227 #ifdef CONFIG_PPC64
228 	case 8:
229 		return __xchg_u64_local(ptr, x);
230 #endif
231 	}
232 	BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg");
233 	return x;
234 }
235 
236 static __always_inline unsigned long
__xchg_relaxed(void * ptr,unsigned long x,unsigned int size)237 __xchg_relaxed(void *ptr, unsigned long x, unsigned int size)
238 {
239 	switch (size) {
240 	case 1:
241 		return __xchg_u8_relaxed(ptr, x);
242 	case 2:
243 		return __xchg_u16_relaxed(ptr, x);
244 	case 4:
245 		return __xchg_u32_relaxed(ptr, x);
246 #ifdef CONFIG_PPC64
247 	case 8:
248 		return __xchg_u64_relaxed(ptr, x);
249 #endif
250 	}
251 	BUILD_BUG_ON_MSG(1, "Unsupported size for __xchg_local");
252 	return x;
253 }
254 #define arch_xchg_local(ptr,x)						     \
255   ({									     \
256      __typeof__(*(ptr)) _x_ = (x);					     \
257      (__typeof__(*(ptr))) __xchg_local((ptr),				     \
258      		(unsigned long)_x_, sizeof(*(ptr))); 			     \
259   })
260 
261 #define arch_xchg_relaxed(ptr, x)					\
262 ({									\
263 	__typeof__(*(ptr)) _x_ = (x);					\
264 	(__typeof__(*(ptr))) __xchg_relaxed((ptr),			\
265 			(unsigned long)_x_, sizeof(*(ptr)));		\
266 })
267 
268 /*
269  * Compare and exchange - if *p == old, set it to new,
270  * and return the old value of *p.
271  */
272 #ifndef CONFIG_PPC_HAS_LBARX_LHARX
273 CMPXCHG_GEN(u8, , PPC_ATOMIC_ENTRY_BARRIER, PPC_ATOMIC_EXIT_BARRIER, "memory");
274 CMPXCHG_GEN(u8, _local, , , "memory");
275 CMPXCHG_GEN(u8, _acquire, , PPC_ACQUIRE_BARRIER, "memory");
276 CMPXCHG_GEN(u8, _relaxed, , , "cc");
277 CMPXCHG_GEN(u16, , PPC_ATOMIC_ENTRY_BARRIER, PPC_ATOMIC_EXIT_BARRIER, "memory");
278 CMPXCHG_GEN(u16, _local, , , "memory");
279 CMPXCHG_GEN(u16, _acquire, , PPC_ACQUIRE_BARRIER, "memory");
280 CMPXCHG_GEN(u16, _relaxed, , , "cc");
281 #else
282 static __always_inline unsigned long
__cmpxchg_u8(volatile unsigned char * p,unsigned long old,unsigned long new)283 __cmpxchg_u8(volatile unsigned char *p, unsigned long old, unsigned long new)
284 {
285 	unsigned int prev;
286 
287 	__asm__ __volatile__ (
288 	PPC_ATOMIC_ENTRY_BARRIER
289 "1:	lbarx	%0,0,%2		# __cmpxchg_u8\n"
290 "	cmpw	0,%0,%3\n"
291 "	bne-	2f\n"
292 "	stbcx.	%4,0,%2\n"
293 "	bne-	1b"
294 	PPC_ATOMIC_EXIT_BARRIER
295 	"\n\
296 2:"
297 	: "=&r" (prev), "+m" (*p)
298 	: "r" (p), "r" (old), "r" (new)
299 	: "cc", "memory");
300 
301 	return prev;
302 }
303 
304 static __always_inline unsigned long
__cmpxchg_u8_local(volatile unsigned char * p,unsigned long old,unsigned long new)305 __cmpxchg_u8_local(volatile unsigned char *p, unsigned long old,
306 			unsigned long new)
307 {
308 	unsigned int prev;
309 
310 	__asm__ __volatile__ (
311 "1:	lbarx	%0,0,%2		# __cmpxchg_u8_local\n"
312 "	cmpw	0,%0,%3\n"
313 "	bne-	2f\n"
314 "	stbcx.	%4,0,%2\n"
315 "	bne-	1b\n"
316 "2:"
317 	: "=&r" (prev), "+m" (*p)
318 	: "r" (p), "r" (old), "r" (new)
319 	: "cc", "memory");
320 
321 	return prev;
322 }
323 
324 static __always_inline unsigned long
__cmpxchg_u8_relaxed(u8 * p,unsigned long old,unsigned long new)325 __cmpxchg_u8_relaxed(u8 *p, unsigned long old, unsigned long new)
326 {
327 	unsigned long prev;
328 
329 	__asm__ __volatile__ (
330 "1:	lbarx	%0,0,%2		# __cmpxchg_u8_relaxed\n"
331 "	cmpw	0,%0,%3\n"
332 "	bne-	2f\n"
333 "	stbcx.	%4,0,%2\n"
334 "	bne-	1b\n"
335 "2:"
336 	: "=&r" (prev), "+m" (*p)
337 	: "r" (p), "r" (old), "r" (new)
338 	: "cc");
339 
340 	return prev;
341 }
342 
343 static __always_inline unsigned long
__cmpxchg_u8_acquire(u8 * p,unsigned long old,unsigned long new)344 __cmpxchg_u8_acquire(u8 *p, unsigned long old, unsigned long new)
345 {
346 	unsigned long prev;
347 
348 	__asm__ __volatile__ (
349 "1:	lbarx	%0,0,%2		# __cmpxchg_u8_acquire\n"
350 "	cmpw	0,%0,%3\n"
351 "	bne-	2f\n"
352 "	stbcx.	%4,0,%2\n"
353 "	bne-	1b\n"
354 	PPC_ACQUIRE_BARRIER
355 "2:"
356 	: "=&r" (prev), "+m" (*p)
357 	: "r" (p), "r" (old), "r" (new)
358 	: "cc", "memory");
359 
360 	return prev;
361 }
362 
363 static __always_inline unsigned long
__cmpxchg_u16(volatile unsigned short * p,unsigned long old,unsigned long new)364 __cmpxchg_u16(volatile unsigned short *p, unsigned long old, unsigned long new)
365 {
366 	unsigned int prev;
367 
368 	__asm__ __volatile__ (
369 	PPC_ATOMIC_ENTRY_BARRIER
370 "1:	lharx	%0,0,%2		# __cmpxchg_u16\n"
371 "	cmpw	0,%0,%3\n"
372 "	bne-	2f\n"
373 "	sthcx.	%4,0,%2\n"
374 "	bne-	1b\n"
375 	PPC_ATOMIC_EXIT_BARRIER
376 "2:"
377 	: "=&r" (prev), "+m" (*p)
378 	: "r" (p), "r" (old), "r" (new)
379 	: "cc", "memory");
380 
381 	return prev;
382 }
383 
384 static __always_inline unsigned long
__cmpxchg_u16_local(volatile unsigned short * p,unsigned long old,unsigned long new)385 __cmpxchg_u16_local(volatile unsigned short *p, unsigned long old,
386 			unsigned long new)
387 {
388 	unsigned int prev;
389 
390 	__asm__ __volatile__ (
391 "1:	lharx	%0,0,%2		# __cmpxchg_u16_local\n"
392 "	cmpw	0,%0,%3\n"
393 "	bne-	2f\n"
394 "	sthcx.	%4,0,%2\n"
395 "	bne-	1b"
396 "2:"
397 	: "=&r" (prev), "+m" (*p)
398 	: "r" (p), "r" (old), "r" (new)
399 	: "cc", "memory");
400 
401 	return prev;
402 }
403 
404 static __always_inline unsigned long
__cmpxchg_u16_relaxed(u16 * p,unsigned long old,unsigned long new)405 __cmpxchg_u16_relaxed(u16 *p, unsigned long old, unsigned long new)
406 {
407 	unsigned long prev;
408 
409 	__asm__ __volatile__ (
410 "1:	lharx	%0,0,%2		# __cmpxchg_u16_relaxed\n"
411 "	cmpw	0,%0,%3\n"
412 "	bne-	2f\n"
413 "	sthcx.	%4,0,%2\n"
414 "	bne-	1b\n"
415 "2:"
416 	: "=&r" (prev), "+m" (*p)
417 	: "r" (p), "r" (old), "r" (new)
418 	: "cc");
419 
420 	return prev;
421 }
422 
423 static __always_inline unsigned long
__cmpxchg_u16_acquire(u16 * p,unsigned long old,unsigned long new)424 __cmpxchg_u16_acquire(u16 *p, unsigned long old, unsigned long new)
425 {
426 	unsigned long prev;
427 
428 	__asm__ __volatile__ (
429 "1:	lharx	%0,0,%2		# __cmpxchg_u16_acquire\n"
430 "	cmpw	0,%0,%3\n"
431 "	bne-	2f\n"
432 "	sthcx.	%4,0,%2\n"
433 "	bne-	1b\n"
434 	PPC_ACQUIRE_BARRIER
435 "2:"
436 	: "=&r" (prev), "+m" (*p)
437 	: "r" (p), "r" (old), "r" (new)
438 	: "cc", "memory");
439 
440 	return prev;
441 }
442 #endif
443 
444 static __always_inline unsigned long
__cmpxchg_u32(volatile unsigned int * p,unsigned long old,unsigned long new)445 __cmpxchg_u32(volatile unsigned int *p, unsigned long old, unsigned long new)
446 {
447 	unsigned int prev;
448 
449 	__asm__ __volatile__ (
450 	PPC_ATOMIC_ENTRY_BARRIER
451 "1:	lwarx	%0,0,%2		# __cmpxchg_u32\n\
452 	cmpw	0,%0,%3\n\
453 	bne-	2f\n"
454 "	stwcx.	%4,0,%2\n\
455 	bne-	1b"
456 	PPC_ATOMIC_EXIT_BARRIER
457 	"\n\
458 2:"
459 	: "=&r" (prev), "+m" (*p)
460 	: "r" (p), "r" (old), "r" (new)
461 	: "cc", "memory");
462 
463 	return prev;
464 }
465 
466 static __always_inline unsigned long
__cmpxchg_u32_local(volatile unsigned int * p,unsigned long old,unsigned long new)467 __cmpxchg_u32_local(volatile unsigned int *p, unsigned long old,
468 			unsigned long new)
469 {
470 	unsigned int prev;
471 
472 	__asm__ __volatile__ (
473 "1:	lwarx	%0,0,%2		# __cmpxchg_u32\n\
474 	cmpw	0,%0,%3\n\
475 	bne-	2f\n"
476 "	stwcx.	%4,0,%2\n\
477 	bne-	1b"
478 	"\n\
479 2:"
480 	: "=&r" (prev), "+m" (*p)
481 	: "r" (p), "r" (old), "r" (new)
482 	: "cc", "memory");
483 
484 	return prev;
485 }
486 
487 static __always_inline unsigned long
__cmpxchg_u32_relaxed(u32 * p,unsigned long old,unsigned long new)488 __cmpxchg_u32_relaxed(u32 *p, unsigned long old, unsigned long new)
489 {
490 	unsigned long prev;
491 
492 	__asm__ __volatile__ (
493 "1:	lwarx	%0,0,%2		# __cmpxchg_u32_relaxed\n"
494 "	cmpw	0,%0,%3\n"
495 "	bne-	2f\n"
496 "	stwcx.	%4,0,%2\n"
497 "	bne-	1b\n"
498 "2:"
499 	: "=&r" (prev), "+m" (*p)
500 	: "r" (p), "r" (old), "r" (new)
501 	: "cc");
502 
503 	return prev;
504 }
505 
506 /*
507  * cmpxchg family don't have order guarantee if cmp part fails, therefore we
508  * can avoid superfluous barriers if we use assembly code to implement
509  * cmpxchg() and cmpxchg_acquire(), however we don't do the similar for
510  * cmpxchg_release() because that will result in putting a barrier in the
511  * middle of a ll/sc loop, which is probably a bad idea. For example, this
512  * might cause the conditional store more likely to fail.
513  */
514 static __always_inline unsigned long
__cmpxchg_u32_acquire(u32 * p,unsigned long old,unsigned long new)515 __cmpxchg_u32_acquire(u32 *p, unsigned long old, unsigned long new)
516 {
517 	unsigned long prev;
518 
519 	__asm__ __volatile__ (
520 "1:	lwarx	%0,0,%2		# __cmpxchg_u32_acquire\n"
521 "	cmpw	0,%0,%3\n"
522 "	bne-	2f\n"
523 "	stwcx.	%4,0,%2\n"
524 "	bne-	1b\n"
525 	PPC_ACQUIRE_BARRIER
526 	"\n"
527 "2:"
528 	: "=&r" (prev), "+m" (*p)
529 	: "r" (p), "r" (old), "r" (new)
530 	: "cc", "memory");
531 
532 	return prev;
533 }
534 
535 #ifdef CONFIG_PPC64
536 static __always_inline unsigned long
__cmpxchg_u64(volatile unsigned long * p,unsigned long old,unsigned long new)537 __cmpxchg_u64(volatile unsigned long *p, unsigned long old, unsigned long new)
538 {
539 	unsigned long prev;
540 
541 	__asm__ __volatile__ (
542 	PPC_ATOMIC_ENTRY_BARRIER
543 "1:	ldarx	%0,0,%2		# __cmpxchg_u64\n\
544 	cmpd	0,%0,%3\n\
545 	bne-	2f\n\
546 	stdcx.	%4,0,%2\n\
547 	bne-	1b"
548 	PPC_ATOMIC_EXIT_BARRIER
549 	"\n\
550 2:"
551 	: "=&r" (prev), "+m" (*p)
552 	: "r" (p), "r" (old), "r" (new)
553 	: "cc", "memory");
554 
555 	return prev;
556 }
557 
558 static __always_inline unsigned long
__cmpxchg_u64_local(volatile unsigned long * p,unsigned long old,unsigned long new)559 __cmpxchg_u64_local(volatile unsigned long *p, unsigned long old,
560 			unsigned long new)
561 {
562 	unsigned long prev;
563 
564 	__asm__ __volatile__ (
565 "1:	ldarx	%0,0,%2		# __cmpxchg_u64\n\
566 	cmpd	0,%0,%3\n\
567 	bne-	2f\n\
568 	stdcx.	%4,0,%2\n\
569 	bne-	1b"
570 	"\n\
571 2:"
572 	: "=&r" (prev), "+m" (*p)
573 	: "r" (p), "r" (old), "r" (new)
574 	: "cc", "memory");
575 
576 	return prev;
577 }
578 
579 static __always_inline unsigned long
__cmpxchg_u64_relaxed(u64 * p,unsigned long old,unsigned long new)580 __cmpxchg_u64_relaxed(u64 *p, unsigned long old, unsigned long new)
581 {
582 	unsigned long prev;
583 
584 	__asm__ __volatile__ (
585 "1:	ldarx	%0,0,%2		# __cmpxchg_u64_relaxed\n"
586 "	cmpd	0,%0,%3\n"
587 "	bne-	2f\n"
588 "	stdcx.	%4,0,%2\n"
589 "	bne-	1b\n"
590 "2:"
591 	: "=&r" (prev), "+m" (*p)
592 	: "r" (p), "r" (old), "r" (new)
593 	: "cc");
594 
595 	return prev;
596 }
597 
598 static __always_inline unsigned long
__cmpxchg_u64_acquire(u64 * p,unsigned long old,unsigned long new)599 __cmpxchg_u64_acquire(u64 *p, unsigned long old, unsigned long new)
600 {
601 	unsigned long prev;
602 
603 	__asm__ __volatile__ (
604 "1:	ldarx	%0,0,%2		# __cmpxchg_u64_acquire\n"
605 "	cmpd	0,%0,%3\n"
606 "	bne-	2f\n"
607 "	stdcx.	%4,0,%2\n"
608 "	bne-	1b\n"
609 	PPC_ACQUIRE_BARRIER
610 	"\n"
611 "2:"
612 	: "=&r" (prev), "+m" (*p)
613 	: "r" (p), "r" (old), "r" (new)
614 	: "cc", "memory");
615 
616 	return prev;
617 }
618 #endif
619 
620 static __always_inline unsigned long
__cmpxchg(volatile void * ptr,unsigned long old,unsigned long new,unsigned int size)621 __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new,
622 	  unsigned int size)
623 {
624 	switch (size) {
625 	case 1:
626 		return __cmpxchg_u8(ptr, old, new);
627 	case 2:
628 		return __cmpxchg_u16(ptr, old, new);
629 	case 4:
630 		return __cmpxchg_u32(ptr, old, new);
631 #ifdef CONFIG_PPC64
632 	case 8:
633 		return __cmpxchg_u64(ptr, old, new);
634 #endif
635 	}
636 	BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg");
637 	return old;
638 }
639 
640 static __always_inline unsigned long
__cmpxchg_local(void * ptr,unsigned long old,unsigned long new,unsigned int size)641 __cmpxchg_local(void *ptr, unsigned long old, unsigned long new,
642 	  unsigned int size)
643 {
644 	switch (size) {
645 	case 1:
646 		return __cmpxchg_u8_local(ptr, old, new);
647 	case 2:
648 		return __cmpxchg_u16_local(ptr, old, new);
649 	case 4:
650 		return __cmpxchg_u32_local(ptr, old, new);
651 #ifdef CONFIG_PPC64
652 	case 8:
653 		return __cmpxchg_u64_local(ptr, old, new);
654 #endif
655 	}
656 	BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg_local");
657 	return old;
658 }
659 
660 static __always_inline unsigned long
__cmpxchg_relaxed(void * ptr,unsigned long old,unsigned long new,unsigned int size)661 __cmpxchg_relaxed(void *ptr, unsigned long old, unsigned long new,
662 		  unsigned int size)
663 {
664 	switch (size) {
665 	case 1:
666 		return __cmpxchg_u8_relaxed(ptr, old, new);
667 	case 2:
668 		return __cmpxchg_u16_relaxed(ptr, old, new);
669 	case 4:
670 		return __cmpxchg_u32_relaxed(ptr, old, new);
671 #ifdef CONFIG_PPC64
672 	case 8:
673 		return __cmpxchg_u64_relaxed(ptr, old, new);
674 #endif
675 	}
676 	BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg_relaxed");
677 	return old;
678 }
679 
680 static __always_inline unsigned long
__cmpxchg_acquire(void * ptr,unsigned long old,unsigned long new,unsigned int size)681 __cmpxchg_acquire(void *ptr, unsigned long old, unsigned long new,
682 		  unsigned int size)
683 {
684 	switch (size) {
685 	case 1:
686 		return __cmpxchg_u8_acquire(ptr, old, new);
687 	case 2:
688 		return __cmpxchg_u16_acquire(ptr, old, new);
689 	case 4:
690 		return __cmpxchg_u32_acquire(ptr, old, new);
691 #ifdef CONFIG_PPC64
692 	case 8:
693 		return __cmpxchg_u64_acquire(ptr, old, new);
694 #endif
695 	}
696 	BUILD_BUG_ON_MSG(1, "Unsupported size for __cmpxchg_acquire");
697 	return old;
698 }
699 #define arch_cmpxchg(ptr, o, n)						 \
700   ({									 \
701      __typeof__(*(ptr)) _o_ = (o);					 \
702      __typeof__(*(ptr)) _n_ = (n);					 \
703      (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_,		 \
704 				    (unsigned long)_n_, sizeof(*(ptr))); \
705   })
706 
707 
708 #define arch_cmpxchg_local(ptr, o, n)					 \
709   ({									 \
710      __typeof__(*(ptr)) _o_ = (o);					 \
711      __typeof__(*(ptr)) _n_ = (n);					 \
712      (__typeof__(*(ptr))) __cmpxchg_local((ptr), (unsigned long)_o_,	 \
713 				    (unsigned long)_n_, sizeof(*(ptr))); \
714   })
715 
716 #define arch_cmpxchg_relaxed(ptr, o, n)					\
717 ({									\
718 	__typeof__(*(ptr)) _o_ = (o);					\
719 	__typeof__(*(ptr)) _n_ = (n);					\
720 	(__typeof__(*(ptr))) __cmpxchg_relaxed((ptr),			\
721 			(unsigned long)_o_, (unsigned long)_n_,		\
722 			sizeof(*(ptr)));				\
723 })
724 
725 #define arch_cmpxchg_acquire(ptr, o, n)					\
726 ({									\
727 	__typeof__(*(ptr)) _o_ = (o);					\
728 	__typeof__(*(ptr)) _n_ = (n);					\
729 	(__typeof__(*(ptr))) __cmpxchg_acquire((ptr),			\
730 			(unsigned long)_o_, (unsigned long)_n_,		\
731 			sizeof(*(ptr)));				\
732 })
733 #ifdef CONFIG_PPC64
734 #define arch_cmpxchg64(ptr, o, n)					\
735   ({									\
736 	BUILD_BUG_ON(sizeof(*(ptr)) != 8);				\
737 	arch_cmpxchg((ptr), (o), (n));					\
738   })
739 #define arch_cmpxchg64_local(ptr, o, n)					\
740   ({									\
741 	BUILD_BUG_ON(sizeof(*(ptr)) != 8);				\
742 	arch_cmpxchg_local((ptr), (o), (n));				\
743   })
744 #define arch_cmpxchg64_relaxed(ptr, o, n)				\
745 ({									\
746 	BUILD_BUG_ON(sizeof(*(ptr)) != 8);				\
747 	arch_cmpxchg_relaxed((ptr), (o), (n));				\
748 })
749 #define arch_cmpxchg64_acquire(ptr, o, n)				\
750 ({									\
751 	BUILD_BUG_ON(sizeof(*(ptr)) != 8);				\
752 	arch_cmpxchg_acquire((ptr), (o), (n));				\
753 })
754 #else
755 #include <asm-generic/cmpxchg-local.h>
756 #define arch_cmpxchg64_local(ptr, o, n) __generic_cmpxchg64_local((ptr), (o), (n))
757 #endif
758 
759 #endif /* __KERNEL__ */
760 #endif /* _ASM_POWERPC_CMPXCHG_H_ */
761