1 #ifndef _ASM_ALPHA_FUTEX_H 2 #define _ASM_ALPHA_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/barrier.h> 10 11 #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ 12 __asm__ __volatile__( \ 13 __ASM_SMP_MB \ 14 "1: ldl_l %0,0(%2)\n" \ 15 insn \ 16 "2: stl_c %1,0(%2)\n" \ 17 " beq %1,4f\n" \ 18 " mov $31,%1\n" \ 19 "3: .subsection 2\n" \ 20 "4: br 1b\n" \ 21 " .previous\n" \ 22 " .section __ex_table,\"a\"\n" \ 23 " .long 1b-.\n" \ 24 " lda $31,3b-1b(%1)\n" \ 25 " .long 2b-.\n" \ 26 " lda $31,3b-2b(%1)\n" \ 27 " .previous\n" \ 28 : "=&r" (oldval), "=&r"(ret) \ 29 : "r" (uaddr), "r"(oparg) \ 30 : "memory") 31 32 static inline int futex_atomic_op_inuser (int encoded_op, u32 __user *uaddr) 33 { 34 int op = (encoded_op >> 28) & 7; 35 int cmp = (encoded_op >> 24) & 15; 36 int oparg = (encoded_op << 8) >> 20; 37 int cmparg = (encoded_op << 20) >> 20; 38 int oldval = 0, ret; 39 if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28)) 40 oparg = 1 << oparg; 41 42 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) 43 return -EFAULT; 44 45 pagefault_disable(); 46 47 switch (op) { 48 case FUTEX_OP_SET: 49 __futex_atomic_op("mov %3,%1\n", ret, oldval, uaddr, oparg); 50 break; 51 case FUTEX_OP_ADD: 52 __futex_atomic_op("addl %0,%3,%1\n", ret, oldval, uaddr, oparg); 53 break; 54 case FUTEX_OP_OR: 55 __futex_atomic_op("or %0,%3,%1\n", ret, oldval, uaddr, oparg); 56 break; 57 case FUTEX_OP_ANDN: 58 __futex_atomic_op("andnot %0,%3,%1\n", ret, oldval, uaddr, oparg); 59 break; 60 case FUTEX_OP_XOR: 61 __futex_atomic_op("xor %0,%3,%1\n", ret, oldval, uaddr, oparg); 62 break; 63 default: 64 ret = -ENOSYS; 65 } 66 67 pagefault_enable(); 68 69 if (!ret) { 70 switch (cmp) { 71 case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break; 72 case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break; 73 case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break; 74 case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break; 75 case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break; 76 case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break; 77 default: ret = -ENOSYS; 78 } 79 } 80 return ret; 81 } 82 83 static inline int 84 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, 85 u32 oldval, u32 newval) 86 { 87 int ret = 0, cmp; 88 u32 prev; 89 90 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) 91 return -EFAULT; 92 93 __asm__ __volatile__ ( 94 __ASM_SMP_MB 95 "1: ldl_l %1,0(%3)\n" 96 " cmpeq %1,%4,%2\n" 97 " beq %2,3f\n" 98 " mov %5,%2\n" 99 "2: stl_c %2,0(%3)\n" 100 " beq %2,4f\n" 101 "3: .subsection 2\n" 102 "4: br 1b\n" 103 " .previous\n" 104 " .section __ex_table,\"a\"\n" 105 " .long 1b-.\n" 106 " lda $31,3b-1b(%0)\n" 107 " .long 2b-.\n" 108 " lda $31,3b-2b(%0)\n" 109 " .previous\n" 110 : "+r"(ret), "=&r"(prev), "=&r"(cmp) 111 : "r"(uaddr), "r"((long)oldval), "r"(newval) 112 : "memory"); 113 114 *uval = prev; 115 return ret; 116 } 117 118 #endif /* __KERNEL__ */ 119 #endif /* _ASM_ALPHA_FUTEX_H */ 120