1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __ASM_OPENRISC_FUTEX_H 3 #define __ASM_OPENRISC_FUTEX_H 4 5 #ifdef __KERNEL__ 6 7 #include <linux/futex.h> 8 #include <linux/uaccess.h> 9 #include <asm/errno.h> 10 11 #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ 12 ({ \ 13 __asm__ __volatile__ ( \ 14 "1: l.lwa %0, %2 \n" \ 15 insn "\n" \ 16 "2: l.swa %2, %1 \n" \ 17 " l.bnf 1b \n" \ 18 " l.ori %1, r0, 0 \n" \ 19 "3: \n" \ 20 ".section .fixup,\"ax\" \n" \ 21 "4: l.j 3b \n" \ 22 " l.addi %1, r0, %3 \n" \ 23 ".previous \n" \ 24 ".section __ex_table,\"a\" \n" \ 25 ".word 1b,4b,2b,4b \n" \ 26 ".previous \n" \ 27 : "=&r" (oldval), "=&r" (ret), "+m" (*uaddr) \ 28 : "i" (-EFAULT), "r" (oparg) \ 29 : "cc", "memory" \ 30 ); \ 31 }) 32 33 static inline int 34 arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr) 35 { 36 int oldval = 0, ret; 37 38 pagefault_disable(); 39 40 switch (op) { 41 case FUTEX_OP_SET: 42 __futex_atomic_op("l.or %1,%4,%4", ret, oldval, uaddr, oparg); 43 break; 44 case FUTEX_OP_ADD: 45 __futex_atomic_op("l.add %1,%0,%4", ret, oldval, uaddr, oparg); 46 break; 47 case FUTEX_OP_OR: 48 __futex_atomic_op("l.or %1,%0,%4", ret, oldval, uaddr, oparg); 49 break; 50 case FUTEX_OP_ANDN: 51 __futex_atomic_op("l.and %1,%0,%4", ret, oldval, uaddr, ~oparg); 52 break; 53 case FUTEX_OP_XOR: 54 __futex_atomic_op("l.xor %1,%0,%4", ret, oldval, uaddr, oparg); 55 break; 56 default: 57 ret = -ENOSYS; 58 } 59 60 pagefault_enable(); 61 62 if (!ret) 63 *oval = oldval; 64 65 return ret; 66 } 67 68 static inline int 69 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, 70 u32 oldval, u32 newval) 71 { 72 int ret = 0; 73 u32 prev; 74 75 if (!access_ok(VERIFY_WRITE, uaddr, sizeof(u32))) 76 return -EFAULT; 77 78 __asm__ __volatile__ ( \ 79 "1: l.lwa %1, %2 \n" \ 80 " l.sfeq %1, %3 \n" \ 81 " l.bnf 3f \n" \ 82 " l.nop \n" \ 83 "2: l.swa %2, %4 \n" \ 84 " l.bnf 1b \n" \ 85 " l.nop \n" \ 86 "3: \n" \ 87 ".section .fixup,\"ax\" \n" \ 88 "4: l.j 3b \n" \ 89 " l.addi %0, r0, %5 \n" \ 90 ".previous \n" \ 91 ".section __ex_table,\"a\" \n" \ 92 ".word 1b,4b,2b,4b \n" \ 93 ".previous \n" \ 94 : "+r" (ret), "=&r" (prev), "+m" (*uaddr) \ 95 : "r" (oldval), "r" (newval), "i" (-EFAULT) \ 96 : "cc", "memory" \ 97 ); 98 99 *uval = prev; 100 return ret; 101 } 102 103 #endif /* __KERNEL__ */ 104 105 #endif /* __ASM_OPENRISC_FUTEX_H */ 106