[urcu.git] / arch_atomic_s390.h

#ifndef _ARCH_ATOMIC_S390_H
#define _ARCH_ATOMIC_S390_H

/*
 * Atomic exchange operations for the S390 architecture. Based on information
 * taken from the Principles of Operation Appendix A "Conditional Swapping
 * Instructions (CS, CDS)".
 *
 * Copyright (c) 2009 Novell, Inc.
 * Author: Jan Blunck <jblunck@suse.de>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#ifndef __SIZEOF_LONG__
#ifdef __s390x__
#define __SIZEOF_LONG__ 8
#else
#define __SIZEOF_LONG__ 4
#endif
#endif

#ifndef BITS_PER_LONG
#define BITS_PER_LONG	(__SIZEOF_LONG__ * 8)
#endif

#ifndef _INCLUDE_API_H

static inline __attribute__((always_inline))
unsigned int atomic_exchange_32(volatile unsigned int *addr, unsigned int val)
{
	unsigned int result;

	__asm__ __volatile__(
		"0:	cs %0,%2,%1\n"
		"	brc 4,0b\n"
		: "=&r"(result), "=m" (*addr)
		: "r"(val), "m" (*addr)
		: "memory", "cc");

	return result;
}

#if (BITS_PER_LONG == 64)

static inline __attribute__((always_inline))
unsigned long atomic_exchange_64(volatile unsigned long *addr,
				 unsigned long val)
{
	unsigned long result;

	__asm__ __volatile__(
		"0:	csg %0,%2,%1\n"
		"	brc 4,0b\n"
		: "=&r"(result), "=m" (*addr)
		: "r"(val), "m" (*addr)
		: "memory", "cc");

	return result;
}

#endif

static inline __attribute__((always_inline))
unsigned long _atomic_exchange(volatile void *addr, unsigned long val, int len)
{
	switch (len) {
	case 4:
		return atomic_exchange_32(addr, val);
#if (BITS_PER_LONG == 64)
	case 8:
		return atomic_exchange_64(addr, val);
#endif
	default:
		__asm__ __volatile__(".long	0xd00d00");
	}

	return 0;
}

#define xchg(addr, v)							\
	(__typeof__(*(addr))) _atomic_exchange((addr), (unsigned long)(v), \
					       sizeof(*(addr)))

#endif /* #ifndef _INCLUDE_API_H */

#endif /* ARCH_ATOMIC_S390_H */
Commit	Line	Data
ac26f1a8 JB	1	#ifndef _ARCH_ATOMIC_S390_H
	2	#define _ARCH_ATOMIC_S390_H
	3
	4	/*
7039fa6f JB	5	* Atomic exchange operations for the S390 architecture. Based on information
	6	* taken from the Principles of Operation Appendix A "Conditional Swapping
	7	* Instructions (CS, CDS)".
ac26f1a8	8	*
7039fa6f	9	* Copyright (c) 2009 Novell, Inc.
ac26f1a8 JB	10	* Author: Jan Blunck <jblunck@suse.de>
ac26f1a8 JB	11	*
7039fa6f JB	12	* Permission is hereby granted, free of charge, to any person obtaining a copy
	13	* of this software and associated documentation files (the "Software"), to
	14	* deal in the Software without restriction, including without limitation the
	15	* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
	16	* sell copies of the Software, and to permit persons to whom the Software is
	17	* furnished to do so, subject to the following conditions:
ac26f1a8	18	*
7039fa6f JB	19	* The above copyright notice and this permission notice shall be included in
	20	* all copies or substantial portions of the Software.
	21	*
	22	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	23	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	24	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	25	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	26	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	27	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
	28	* IN THE SOFTWARE.
ac26f1a8 JB	29	*/
	30
	31	#ifndef __SIZEOF_LONG__
	32	#ifdef __s390x__
	33	#define __SIZEOF_LONG__ 8
	34	#else
	35	#define __SIZEOF_LONG__ 4
	36	#endif
	37	#endif
	38
	39	#ifndef BITS_PER_LONG
	40	#define BITS_PER_LONG (__SIZEOF_LONG__ * 8)
	41	#endif
	42
	43	#ifndef _INCLUDE_API_H
	44
a9a05d42	45	static inline __attribute__((always_inline))
ac26f1a8 JB	46	unsigned int atomic_exchange_32(volatile unsigned int *addr, unsigned int val)
	47	{
	48	unsigned int result;
	49
	50	__asm__ __volatile__(
	51	"0: cs %0,%2,%1\n"
	52	" brc 4,0b\n"
	53	: "=&r"(result), "=m" (*addr)
	54	: "r"(val), "m" (*addr)
	55	: "memory", "cc");
	56
	57	return result;
	58	}
	59
	60	#if (BITS_PER_LONG == 64)
	61
a9a05d42	62	static inline __attribute__((always_inline))
ac26f1a8 JB	63	unsigned long atomic_exchange_64(volatile unsigned long *addr,
	64	unsigned long val)
	65	{
	66	unsigned long result;
	67
	68	__asm__ __volatile__(
	69	"0: csg %0,%2,%1\n"
	70	" brc 4,0b\n"
	71	: "=&r"(result), "=m" (*addr)
	72	: "r"(val), "m" (*addr)
	73	: "memory", "cc");
	74
	75	return result;
	76	}
	77
	78	#endif
	79
a9a05d42	80	static inline __attribute__((always_inline))
ac26f1a8 JB	81	unsigned long _atomic_exchange(volatile void *addr, unsigned long val, int len)
	82	{
	83	switch (len) {
	84	case 4:
	85	return atomic_exchange_32(addr, val);
	86	#if (BITS_PER_LONG == 64)
	87	case 8:
	88	return atomic_exchange_64(addr, val);
	89	#endif
	90	default:
	91	__asm__ __volatile__(".long 0xd00d00");
	92	}
	93
	94	return 0;
	95	}
	96
a9a05d42 JB	97	#define xchg(addr, v) \
	98	(__typeof__(*(addr))) _atomic_exchange((addr), (unsigned long)(v), \
	99	sizeof(*(addr)))
ac26f1a8 JB	100
	101	#endif /* #ifndef _INCLUDE_API_H */
	102
	103	#endif /* ARCH_ATOMIC_S390_H */