1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright IBM Corp. 1999, 2009 4 * 5 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> 6 */ 7 8 #ifndef __ASM_BARRIER_H 9 #define __ASM_BARRIER_H 10 11 /* 12 * Force strict CPU ordering. 13 * And yes, this is required on UP too when we're talking 14 * to devices. 15 */ 16 17 #ifdef CONFIG_HAVE_MARCH_Z196_FEATURES 18 /* Fast-BCR without checkpoint synchronization */ 19 #define __ASM_BARRIER "bcr 14,0\n" 20 #else 21 #define __ASM_BARRIER "bcr 15,0\n" 22 #endif 23 24 #define mb() do { asm volatile(__ASM_BARRIER : : : "memory"); } while (0) 25 26 #define rmb() barrier() 27 #define wmb() barrier() 28 #define dma_rmb() mb() 29 #define dma_wmb() mb() 30 #define __smp_mb() mb() 31 #define __smp_rmb() rmb() 32 #define __smp_wmb() wmb() 33 34 #define __smp_store_release(p, v) \ 35 do { \ 36 compiletime_assert_atomic_type(*p); \ 37 barrier(); \ 38 WRITE_ONCE(*p, v); \ 39 } while (0) 40 41 #define __smp_load_acquire(p) \ 42 ({ \ 43 typeof(*p) ___p1 = READ_ONCE(*p); \ 44 compiletime_assert_atomic_type(*p); \ 45 barrier(); \ 46 ___p1; \ 47 }) 48 49 #define __smp_mb__before_atomic() barrier() 50 #define __smp_mb__after_atomic() barrier() 51 52 /** 53 * array_index_mask_nospec - generate a mask for array_idx() that is 54 * ~0UL when the bounds check succeeds and 0 otherwise 55 * @index: array element index 56 * @size: number of elements in array 57 */ 58 #define array_index_mask_nospec array_index_mask_nospec 59 static inline unsigned long array_index_mask_nospec(unsigned long index, 60 unsigned long size) 61 { 62 unsigned long mask; 63 64 if (__builtin_constant_p(size) && size > 0) { 65 asm(" clgr %2,%1\n" 66 " slbgr %0,%0\n" 67 :"=d" (mask) : "d" (size-1), "d" (index) :"cc"); 68 return mask; 69 } 70 asm(" clgr %1,%2\n" 71 " slbgr %0,%0\n" 72 :"=d" (mask) : "d" (size), "d" (index) :"cc"); 73 return ~mask; 74 } 75 76 #include <asm-generic/barrier.h> 77 78 #endif /* __ASM_BARRIER_H */ 79