xref: /OK3568_Linux_fs/kernel/arch/s390/include/asm/cmpxchg.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright IBM Corp. 1999, 2011
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #ifndef __ASM_CMPXCHG_H
9*4882a593Smuzhiyun #define __ASM_CMPXCHG_H
10*4882a593Smuzhiyun 
11*4882a593Smuzhiyun #include <linux/mmdebug.h>
12*4882a593Smuzhiyun #include <linux/types.h>
13*4882a593Smuzhiyun #include <linux/bug.h>
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun #define cmpxchg(ptr, o, n)						\
16*4882a593Smuzhiyun ({									\
17*4882a593Smuzhiyun 	__typeof__(*(ptr)) __o = (o);					\
18*4882a593Smuzhiyun 	__typeof__(*(ptr)) __n = (n);					\
19*4882a593Smuzhiyun 	(__typeof__(*(ptr))) __sync_val_compare_and_swap((ptr),__o,__n);\
20*4882a593Smuzhiyun })
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun #define cmpxchg64	cmpxchg
23*4882a593Smuzhiyun #define cmpxchg_local	cmpxchg
24*4882a593Smuzhiyun #define cmpxchg64_local	cmpxchg
25*4882a593Smuzhiyun 
26*4882a593Smuzhiyun #define xchg(ptr, x)							\
27*4882a593Smuzhiyun ({									\
28*4882a593Smuzhiyun 	__typeof__(ptr) __ptr = (ptr);					\
29*4882a593Smuzhiyun 	__typeof__(*(ptr)) __old;					\
30*4882a593Smuzhiyun 	do {								\
31*4882a593Smuzhiyun 		__old = *__ptr;						\
32*4882a593Smuzhiyun 	} while (!__sync_bool_compare_and_swap(__ptr, __old, x));	\
33*4882a593Smuzhiyun 	__old;								\
34*4882a593Smuzhiyun })
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun #define __cmpxchg_double(p1, p2, o1, o2, n1, n2)			\
37*4882a593Smuzhiyun ({									\
38*4882a593Smuzhiyun 	register __typeof__(*(p1)) __old1 asm("2") = (o1);		\
39*4882a593Smuzhiyun 	register __typeof__(*(p2)) __old2 asm("3") = (o2);		\
40*4882a593Smuzhiyun 	register __typeof__(*(p1)) __new1 asm("4") = (n1);		\
41*4882a593Smuzhiyun 	register __typeof__(*(p2)) __new2 asm("5") = (n2);		\
42*4882a593Smuzhiyun 	int cc;								\
43*4882a593Smuzhiyun 	asm volatile(							\
44*4882a593Smuzhiyun 		"	cdsg	%[old],%[new],%[ptr]\n"			\
45*4882a593Smuzhiyun 		"	ipm	%[cc]\n"				\
46*4882a593Smuzhiyun 		"	srl	%[cc],28"				\
47*4882a593Smuzhiyun 		: [cc] "=d" (cc), [old] "+d" (__old1), "+d" (__old2)	\
48*4882a593Smuzhiyun 		: [new] "d" (__new1), "d" (__new2),			\
49*4882a593Smuzhiyun 		  [ptr] "Q" (*(p1)), "Q" (*(p2))			\
50*4882a593Smuzhiyun 		: "memory", "cc");					\
51*4882a593Smuzhiyun 	!cc;								\
52*4882a593Smuzhiyun })
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun #define cmpxchg_double(p1, p2, o1, o2, n1, n2)				\
55*4882a593Smuzhiyun ({									\
56*4882a593Smuzhiyun 	__typeof__(p1) __p1 = (p1);					\
57*4882a593Smuzhiyun 	__typeof__(p2) __p2 = (p2);					\
58*4882a593Smuzhiyun 	BUILD_BUG_ON(sizeof(*(p1)) != sizeof(long));			\
59*4882a593Smuzhiyun 	BUILD_BUG_ON(sizeof(*(p2)) != sizeof(long));			\
60*4882a593Smuzhiyun 	VM_BUG_ON((unsigned long)((__p1) + 1) != (unsigned long)(__p2));\
61*4882a593Smuzhiyun 	__cmpxchg_double(__p1, __p2, o1, o2, n1, n2);			\
62*4882a593Smuzhiyun })
63*4882a593Smuzhiyun 
64*4882a593Smuzhiyun #define system_has_cmpxchg_double()	1
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun #endif /* __ASM_CMPXCHG_H */
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