1 #ifndef _ASM_X86_FUTEX_H 2 #define _ASM_X86_FUTEX_H 3 4 #ifdef __KERNEL__ 5 6 #include <linux/futex.h> 7 #include <linux/uaccess.h> 8 9 #include <asm/asm.h> 10 #include <asm/errno.h> 11 #include <asm/processor.h> 12 #include <asm/smap.h> 13 14 #define __futex_atomic_op1(insn, ret, oldval, uaddr, oparg) \ 15 asm volatile("\t" ASM_STAC "\n" \ 16 "1:\t" insn "\n" \ 17 "2:\t" ASM_CLAC "\n" \ 18 "\t.section .fixup,\"ax\"\n" \ 19 "3:\tmov\t%3, %1\n" \ 20 "\tjmp\t2b\n" \ 21 "\t.previous\n" \ 22 _ASM_EXTABLE(1b, 3b) \ 23 : "=r" (oldval), "=r" (ret), "+m" (*uaddr) \ 24 : "i" (-EFAULT), "0" (oparg), "1" (0)) 25 26 #define __futex_atomic_op2(insn, ret, oldval, uaddr, oparg) \ 27 asm volatile("\t" ASM_STAC "\n" \ 28 "1:\tmovl %2, %0\n" \ 29 "\tmovl\t%0, %3\n" \ 30 "\t" insn "\n" \ 31 "2:\t" LOCK_PREFIX "cmpxchgl %3, %2\n" \ 32 "\tjnz\t1b\n" \ 33 "3:\t" ASM_CLAC "\n" \ 34 "\t.section .fixup,\"ax\"\n" \ 35 "4:\tmov\t%5, %1\n" \ 36 "\tjmp\t3b\n" \ 37 "\t.previous\n" \ 38 _ASM_EXTABLE(1b, 4b) \ 39 _ASM_EXTABLE(2b, 4b) \ 40 : "=&a" (oldval), "=&r" (ret), \ 41 "+m" (*uaddr), "=&r" (tem) \ 42 : "r" (oparg), "i" (-EFAULT), "1" (0)) 43 44 static inline int arch_futex_atomic_op_inuser(int op, int oparg, int *oval, 45 u32 __user *uaddr) 46 { 47 int oldval = 0, ret, tem; 48 49 pagefault_disable(); 50 51 switch (op) { 52 case FUTEX_OP_SET: 53 __futex_atomic_op1("xchgl %0, %2", ret, oldval, uaddr, oparg); 54 break; 55 case FUTEX_OP_ADD: 56 __futex_atomic_op1(LOCK_PREFIX "xaddl %0, %2", ret, oldval, 57 uaddr, oparg); 58 break; 59 case FUTEX_OP_OR: 60 __futex_atomic_op2("orl %4, %3", ret, oldval, uaddr, oparg); 61 break; 62 case FUTEX_OP_ANDN: 63 __futex_atomic_op2("andl %4, %3", ret, oldval, uaddr, ~oparg); 64 break; 65 case FUTEX_OP_XOR: 66 __futex_atomic_op2("xorl %4, %3", ret, oldval, uaddr, oparg); 67 break; 68 default: 69 ret = -ENOSYS; 70 } 71 72 pagefault_enable(); 73 74 if (!ret) 75 *oval = oldval; 76 77 return ret; 78 } 79 80 static inline int futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, 81 u32 oldval, u32 newval) 82 { 83 return user_atomic_cmpxchg_inatomic(uval, uaddr, oldval, newval); 84 } 85 86 #endif 87 #endif /* _ASM_X86_FUTEX_H */ 88