1 #ifndef _ASM_POWERPC_FUTEX_H 2 #define _ASM_POWERPC_FUTEX_H 3 4 #ifdef __KERNEL__ 5 6 #include <linux/futex.h> 7 #include <linux/uaccess.h> 8 #include <asm/errno.h> 9 #include <asm/synch.h> 10 #include <asm/asm-compat.h> 11 12 #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ 13 __asm__ __volatile ( \ 14 PPC_ATOMIC_ENTRY_BARRIER \ 15 "1: lwarx %0,0,%2\n" \ 16 insn \ 17 PPC405_ERR77(0, %2) \ 18 "2: stwcx. %1,0,%2\n" \ 19 "bne- 1b\n" \ 20 PPC_ATOMIC_EXIT_BARRIER \ 21 "li %1,0\n" \ 22 "3: .section .fixup,\"ax\"\n" \ 23 "4: li %1,%3\n" \ 24 "b 3b\n" \ 25 ".previous\n" \ 26 EX_TABLE(1b, 4b) \ 27 EX_TABLE(2b, 4b) \ 28 : "=&r" (oldval), "=&r" (ret) \ 29 : "b" (uaddr), "i" (-EFAULT), "r" (oparg) \ 30 : "cr0", "memory") 31 32 static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval, 33 u32 __user *uaddr) 34 { 35 int oldval = 0, ret; 36 37 pagefault_disable(); 38 39 switch (op) { 40 case FUTEX_OP_SET: 41 __futex_atomic_op("mr %1,%4\n", ret, oldval, uaddr, oparg); 42 break; 43 case FUTEX_OP_ADD: 44 __futex_atomic_op("add %1,%0,%4\n", ret, oldval, uaddr, oparg); 45 break; 46 case FUTEX_OP_OR: 47 __futex_atomic_op("or %1,%0,%4\n", ret, oldval, uaddr, oparg); 48 break; 49 case FUTEX_OP_ANDN: 50 __futex_atomic_op("andc %1,%0,%4\n", ret, oldval, uaddr, oparg); 51 break; 52 case FUTEX_OP_XOR: 53 __futex_atomic_op("xor %1,%0,%4\n", ret, oldval, uaddr, oparg); 54 break; 55 default: 56 ret = -ENOSYS; 57 } 58 59 pagefault_enable(); 60 61 if (!ret) 62 *oval = oldval; 63 64 return ret; 65 } 66 67 static inline int 68 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, 69 u32 oldval, u32 newval) 70 { 71 int ret = 0; 72 u32 prev; 73 74 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) 75 return -EFAULT; 76 77 __asm__ __volatile__ ( 78 PPC_ATOMIC_ENTRY_BARRIER 79 "1: lwarx %1,0,%3 # futex_atomic_cmpxchg_inatomic\n\ 80 cmpw 0,%1,%4\n\ 81 bne- 3f\n" 82 PPC405_ERR77(0,%3) 83 "2: stwcx. %5,0,%3\n\ 84 bne- 1b\n" 85 PPC_ATOMIC_EXIT_BARRIER 86 "3: .section .fixup,\"ax\"\n\ 87 4: li %0,%6\n\ 88 b 3b\n\ 89 .previous\n" 90 EX_TABLE(1b, 4b) 91 EX_TABLE(2b, 4b) 92 : "+r" (ret), "=&r" (prev), "+m" (*uaddr) 93 : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT) 94 : "cc", "memory"); 95 96 *uval = prev; 97 return ret; 98 } 99 100 #endif /* __KERNEL__ */ 101 #endif /* _ASM_POWERPC_FUTEX_H */ 102