1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_MICROBLAZE_FUTEX_H 3 #define _ASM_MICROBLAZE_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: lwx %0, %2, r0; " \ 15 insn \ 16 "2: swx %1, %2, r0; \ 17 addic %1, r0, 0; \ 18 bnei %1, 1b; \ 19 3: \ 20 .section .fixup,\"ax\"; \ 21 4: brid 3b; \ 22 addik %1, r0, %3; \ 23 .previous; \ 24 .section __ex_table,\"a\"; \ 25 .word 1b,4b,2b,4b; \ 26 .previous;" \ 27 : "=&r" (oldval), "=&r" (ret) \ 28 : "r" (uaddr), "i" (-EFAULT), "r" (oparg) \ 29 ); \ 30 }) 31 32 static inline int 33 arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr) 34 { 35 int oldval = 0, ret; 36 37 if (!access_ok(uaddr, sizeof(u32))) 38 return -EFAULT; 39 40 switch (op) { 41 case FUTEX_OP_SET: 42 __futex_atomic_op("or %1,%4,%4;", ret, oldval, uaddr, oparg); 43 break; 44 case FUTEX_OP_ADD: 45 __futex_atomic_op("add %1,%0,%4;", ret, oldval, uaddr, oparg); 46 break; 47 case FUTEX_OP_OR: 48 __futex_atomic_op("or %1,%0,%4;", ret, oldval, uaddr, oparg); 49 break; 50 case FUTEX_OP_ANDN: 51 __futex_atomic_op("andn %1,%0,%4;", ret, oldval, uaddr, oparg); 52 break; 53 case FUTEX_OP_XOR: 54 __futex_atomic_op("xor %1,%0,%4;", ret, oldval, uaddr, oparg); 55 break; 56 default: 57 ret = -ENOSYS; 58 } 59 60 if (!ret) 61 *oval = oldval; 62 63 return ret; 64 } 65 66 static inline int 67 futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, 68 u32 oldval, u32 newval) 69 { 70 int ret = 0, cmp; 71 u32 prev; 72 73 if (!access_ok(uaddr, sizeof(u32))) 74 return -EFAULT; 75 76 __asm__ __volatile__ ("1: lwx %1, %3, r0; \ 77 cmp %2, %1, %4; \ 78 bnei %2, 3f; \ 79 2: swx %5, %3, r0; \ 80 addic %2, r0, 0; \ 81 bnei %2, 1b; \ 82 3: \ 83 .section .fixup,\"ax\"; \ 84 4: brid 3b; \ 85 addik %0, r0, %6; \ 86 .previous; \ 87 .section __ex_table,\"a\"; \ 88 .word 1b,4b,2b,4b; \ 89 .previous;" \ 90 : "+r" (ret), "=&r" (prev), "=&r"(cmp) \ 91 : "r" (uaddr), "r" (oldval), "r" (newval), "i" (-EFAULT)); 92 93 *uval = prev; 94 return ret; 95 } 96 97 #endif /* __KERNEL__ */ 98 99 #endif 100