1 #ifndef _ASM_FUTEX_H 2 #define _ASM_FUTEX_H 3 4 #include <linux/futex.h> 5 #include <linux/uaccess.h> 6 #include <asm/errno.h> 7 8 #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \ 9 do { \ 10 register unsigned long r8 __asm ("r8") = 0; \ 11 __asm__ __volatile__( \ 12 " mf;; \n" \ 13 "[1:] " insn ";; \n" \ 14 " .xdata4 \"__ex_table\", 1b-., 2f-. \n" \ 15 "[2:]" \ 16 : "+r" (r8), "=r" (oldval) \ 17 : "r" (uaddr), "r" (oparg) \ 18 : "memory"); \ 19 ret = r8; \ 20 } while (0) 21 22 #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \ 23 do { \ 24 register unsigned long r8 __asm ("r8") = 0; \ 25 int val, newval; \ 26 do { \ 27 __asm__ __volatile__( \ 28 " mf;; \n" \ 29 "[1:] ld4 %3=[%4];; \n" \ 30 " mov %2=%3 \n" \ 31 insn ";; \n" \ 32 " mov ar.ccv=%2;; \n" \ 33 "[2:] cmpxchg4.acq %1=[%4],%3,ar.ccv;; \n" \ 34 " .xdata4 \"__ex_table\", 1b-., 3f-.\n" \ 35 " .xdata4 \"__ex_table\", 2b-., 3f-.\n" \ 36 "[3:]" \ 37 : "+r" (r8), "=r" (val), "=&r" (oldval), \ 38 "=&r" (newval) \ 39 : "r" (uaddr), "r" (oparg) \ 40 : "memory"); \ 41 if (unlikely (r8)) \ 42 break; \ 43 } while (unlikely (val != oldval)); \ 44 ret = r8; \ 45 } while (0) 46 47 static inline int 48 arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr) 49 { 50 int oldval = 0, ret; 51 52 pagefault_disable(); 53 54 switch (op) { 55 case FUTEX_OP_SET: 56 __futex_atomic_op1("xchg4 %1=[%2],%3", ret, oldval, uaddr, 57 oparg); 58 break; 59 case FUTEX_OP_ADD: 60 __futex_atomic_op2("add %3=%3,%5", ret, oldval, uaddr, oparg); 61 break; 62 case FUTEX_OP_OR: 63 __futex_atomic_op2("or %3=%3,%5", ret, oldval, uaddr, oparg); 64 break; 65 case FUTEX_OP_ANDN: 66 __futex_atomic_op2("and %3=%3,%5", ret, oldval, uaddr, 67 ~oparg); 68 break; 69 case FUTEX_OP_XOR: 70 __futex_atomic_op2("xor %3=%3,%5", ret, oldval, uaddr, oparg); 71 break; 72 default: 73 ret = -ENOSYS; 74 } 75 76 pagefault_enable(); 77 78 if (!ret) 79 *oval = oldval; 80 81 return ret; 82 } 83 84 static inline int 85 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, 86 u32 oldval, u32 newval) 87 { 88 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) 89 return -EFAULT; 90 91 { 92 register unsigned long r8 __asm ("r8") = 0; 93 unsigned long prev; 94 __asm__ __volatile__( 95 " mf;; \n" 96 " mov ar.ccv=%4;; \n" 97 "[1:] cmpxchg4.acq %1=[%2],%3,ar.ccv \n" 98 " .xdata4 \"__ex_table\", 1b-., 2f-. \n" 99 "[2:]" 100 : "+r" (r8), "=&r" (prev) 101 : "r" (uaddr), "r" (newval), 102 "rO" ((long) (unsigned) oldval) 103 : "memory"); 104 *uval = prev; 105 return r8; 106 } 107 } 108 109 #endif /* _ASM_FUTEX_H */ 110