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 ".section __ex_table,\"a\"\n" \ 27 ".align 3\n" \ 28 PPC_LONG "1b,4b,2b,4b\n" \ 29 ".previous" \ 30 : "=&r" (oldval), "=&r" (ret) \ 31 : "b" (uaddr), "i" (-EFAULT), "r" (oparg) \ 32 : "cr0", "memory") 33 34 static inline int futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr) 35 { 36 int op = (encoded_op >> 28) & 7; 37 int cmp = (encoded_op >> 24) & 15; 38 int oparg = (encoded_op << 8) >> 20; 39 int cmparg = (encoded_op << 20) >> 20; 40 int oldval = 0, ret; 41 if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) 42 oparg = 1 << oparg; 43 44 if (! access_ok (VERIFY_WRITE, uaddr, sizeof(u32))) 45 return -EFAULT; 46 47 pagefault_disable(); 48 49 switch (op) { 50 case FUTEX_OP_SET: 51 __futex_atomic_op("mr %1,%4\n", ret, oldval, uaddr, oparg); 52 break; 53 case FUTEX_OP_ADD: 54 __futex_atomic_op("add %1,%0,%4\n", ret, oldval, uaddr, oparg); 55 break; 56 case FUTEX_OP_OR: 57 __futex_atomic_op("or %1,%0,%4\n", ret, oldval, uaddr, oparg); 58 break; 59 case FUTEX_OP_ANDN: 60 __futex_atomic_op("andc %1,%0,%4\n", ret, oldval, uaddr, oparg); 61 break; 62 case FUTEX_OP_XOR: 63 __futex_atomic_op("xor %1,%0,%4\n", ret, oldval, uaddr, oparg); 64 break; 65 default: 66 ret = -ENOSYS; 67 } 68 69 pagefault_enable(); 70 71 if (!ret) { 72 switch (cmp) { 73 case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break; 74 case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break; 75 case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break; 76 case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break; 77 case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break; 78 case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break; 79 default: ret = -ENOSYS; 80 } 81 } 82 return ret; 83 } 84 85 static inline int 86 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, 87 u32 oldval, u32 newval) 88 { 89 int ret = 0; 90 u32 prev; 91 92 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) 93 return -EFAULT; 94 95 __asm__ __volatile__ ( 96 PPC_ATOMIC_ENTRY_BARRIER 97 "1: lwarx %1,0,%3 # futex_atomic_cmpxchg_inatomic\n\ 98 cmpw 0,%1,%4\n\ 99 bne- 3f\n" 100 PPC405_ERR77(0,%3) 101 "2: stwcx. %5,0,%3\n\ 102 bne- 1b\n" 103 PPC_ATOMIC_EXIT_BARRIER 104 "3: .section .fixup,\"ax\"\n\ 105 4: li %0,%6\n\ 106 b 3b\n\ 107 .previous\n\ 108 .section __ex_table,\"a\"\n\ 109 .align 3\n\ 110 " PPC_LONG "1b,4b,2b,4b\n\ 111 .previous" \ 112 : "+r" (ret), "=&r" (prev), "+m" (*uaddr) 113 : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT) 114 : "cc", "memory"); 115 116 *uval = prev; 117 return ret; 118 } 119 120 #endif /* __KERNEL__ */ 121 #endif /* _ASM_POWERPC_FUTEX_H */ 122