1 /* 2 * Copyright IBM Corp. 1999, 2011 3 * 4 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>, 5 */ 6 7 #ifndef __ASM_CMPXCHG_H 8 #define __ASM_CMPXCHG_H 9 10 #include <linux/mmdebug.h> 11 #include <linux/types.h> 12 #include <linux/bug.h> 13 14 #define cmpxchg(ptr, o, n) \ 15 ({ \ 16 __typeof__(*(ptr)) __o = (o); \ 17 __typeof__(*(ptr)) __n = (n); \ 18 (__typeof__(*(ptr))) __sync_val_compare_and_swap((ptr),__o,__n);\ 19 }) 20 21 #define cmpxchg64 cmpxchg 22 #define cmpxchg_local cmpxchg 23 #define cmpxchg64_local cmpxchg 24 25 #define xchg(ptr, x) \ 26 ({ \ 27 __typeof__(ptr) __ptr = (ptr); \ 28 __typeof__(*(ptr)) __old; \ 29 do { \ 30 __old = *__ptr; \ 31 } while (!__sync_bool_compare_and_swap(__ptr, __old, x)); \ 32 __old; \ 33 }) 34 35 #define __HAVE_ARCH_CMPXCHG 36 37 #define __cmpxchg_double_op(p1, p2, o1, o2, n1, n2, insn) \ 38 ({ \ 39 register __typeof__(*(p1)) __old1 asm("2") = (o1); \ 40 register __typeof__(*(p2)) __old2 asm("3") = (o2); \ 41 register __typeof__(*(p1)) __new1 asm("4") = (n1); \ 42 register __typeof__(*(p2)) __new2 asm("5") = (n2); \ 43 int cc; \ 44 asm volatile( \ 45 insn " %[old],%[new],%[ptr]\n" \ 46 " ipm %[cc]\n" \ 47 " srl %[cc],28" \ 48 : [cc] "=d" (cc), [old] "+d" (__old1), "+d" (__old2) \ 49 : [new] "d" (__new1), "d" (__new2), \ 50 [ptr] "Q" (*(p1)), "Q" (*(p2)) \ 51 : "memory", "cc"); \ 52 !cc; \ 53 }) 54 55 #define __cmpxchg_double_4(p1, p2, o1, o2, n1, n2) \ 56 __cmpxchg_double_op(p1, p2, o1, o2, n1, n2, "cds") 57 58 #define __cmpxchg_double_8(p1, p2, o1, o2, n1, n2) \ 59 __cmpxchg_double_op(p1, p2, o1, o2, n1, n2, "cdsg") 60 61 extern void __cmpxchg_double_called_with_bad_pointer(void); 62 63 #define __cmpxchg_double(p1, p2, o1, o2, n1, n2) \ 64 ({ \ 65 int __ret; \ 66 switch (sizeof(*(p1))) { \ 67 case 4: \ 68 __ret = __cmpxchg_double_4(p1, p2, o1, o2, n1, n2); \ 69 break; \ 70 case 8: \ 71 __ret = __cmpxchg_double_8(p1, p2, o1, o2, n1, n2); \ 72 break; \ 73 default: \ 74 __cmpxchg_double_called_with_bad_pointer(); \ 75 } \ 76 __ret; \ 77 }) 78 79 #define cmpxchg_double(p1, p2, o1, o2, n1, n2) \ 80 ({ \ 81 __typeof__(p1) __p1 = (p1); \ 82 __typeof__(p2) __p2 = (p2); \ 83 int __ret; \ 84 BUILD_BUG_ON(sizeof(*(p1)) != sizeof(long)); \ 85 BUILD_BUG_ON(sizeof(*(p2)) != sizeof(long)); \ 86 VM_BUG_ON((unsigned long)((__p1) + 1) != (unsigned long)(__p2));\ 87 if (sizeof(long) == 4) \ 88 __ret = __cmpxchg_double_4(__p1, __p2, o1, o2, n1, n2); \ 89 else \ 90 __ret = __cmpxchg_double_8(__p1, __p2, o1, o2, n1, n2); \ 91 __ret; \ 92 }) 93 94 #define system_has_cmpxchg_double() 1 95 96 #endif /* __ASM_CMPXCHG_H */ 97