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Diffstat (limited to 'arch/s390/include/asm/barrier.h')
-rw-r--r-- | arch/s390/include/asm/barrier.h | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h new file mode 100644 index 0000000000..82de2a7c41 --- /dev/null +++ b/arch/s390/include/asm/barrier.h @@ -0,0 +1,82 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright IBM Corp. 1999, 2009 + * + * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> + */ + +#ifndef __ASM_BARRIER_H +#define __ASM_BARRIER_H + +/* + * Force strict CPU ordering. + * And yes, this is required on UP too when we're talking + * to devices. + */ + +#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES +/* Fast-BCR without checkpoint synchronization */ +#define __ASM_BCR_SERIALIZE "bcr 14,0\n" +#else +#define __ASM_BCR_SERIALIZE "bcr 15,0\n" +#endif + +static __always_inline void bcr_serialize(void) +{ + asm volatile(__ASM_BCR_SERIALIZE : : : "memory"); +} + +#define __mb() bcr_serialize() +#define __rmb() barrier() +#define __wmb() barrier() +#define __dma_rmb() __mb() +#define __dma_wmb() __mb() +#define __smp_mb() __mb() +#define __smp_rmb() __rmb() +#define __smp_wmb() __wmb() + +#define __smp_store_release(p, v) \ +do { \ + compiletime_assert_atomic_type(*p); \ + barrier(); \ + WRITE_ONCE(*p, v); \ +} while (0) + +#define __smp_load_acquire(p) \ +({ \ + typeof(*p) ___p1 = READ_ONCE(*p); \ + compiletime_assert_atomic_type(*p); \ + barrier(); \ + ___p1; \ +}) + +#define __smp_mb__before_atomic() barrier() +#define __smp_mb__after_atomic() barrier() + +/** + * array_index_mask_nospec - generate a mask for array_idx() that is + * ~0UL when the bounds check succeeds and 0 otherwise + * @index: array element index + * @size: number of elements in array + */ +#define array_index_mask_nospec array_index_mask_nospec +static inline unsigned long array_index_mask_nospec(unsigned long index, + unsigned long size) +{ + unsigned long mask; + + if (__builtin_constant_p(size) && size > 0) { + asm(" clgr %2,%1\n" + " slbgr %0,%0\n" + :"=d" (mask) : "d" (size-1), "d" (index) :"cc"); + return mask; + } + asm(" clgr %1,%2\n" + " slbgr %0,%0\n" + :"=d" (mask) : "d" (size), "d" (index) :"cc"); + return ~mask; +} + +#include <asm-generic/barrier.h> + +#endif /* __ASM_BARRIER_H */ |