| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #ifndef _ASM_HEXAGON_FUTEX_H |
| 3 | #define _ASM_HEXAGON_FUTEX_H |
| 4 | |
| 5 | #ifdef __KERNEL__ |
| 6 | |
| 7 | #include <linux/futex.h> |
| 8 | #include <linux/uaccess.h> |
| 9 | #include <asm/errno.h> |
| 10 | |
| 11 | /* XXX TODO-- need to add sync barriers! */ |
| 12 | |
| 13 | #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ |
| 14 | __asm__ __volatile( \ |
| 15 | "1: %0 = memw_locked(%3);\n" \ |
| 16 | /* For example: %1 = %4 */ \ |
| 17 | insn \ |
| 18 | "2: memw_locked(%3,p2) = %1;\n" \ |
| 19 | " if (!p2) jump 1b;\n" \ |
| 20 | " %1 = #0;\n" \ |
| 21 | "3:\n" \ |
| 22 | ".section .fixup,\"ax\"\n" \ |
| 23 | "4: %1 = #%5;\n" \ |
| 24 | " jump 3b\n" \ |
| 25 | ".previous\n" \ |
| 26 | ".section __ex_table,\"a\"\n" \ |
| 27 | ".long 1b,4b,2b,4b\n" \ |
| 28 | ".previous\n" \ |
| 29 | : "=&r" (oldval), "=&r" (ret), "+m" (*uaddr) \ |
| 30 | : "r" (uaddr), "r" (oparg), "i" (-EFAULT) \ |
| 31 | : "p2", "memory") |
| 32 | |
| 33 | |
| 34 | static inline int |
| 35 | arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr) |
| 36 | { |
| 37 | int oldval = 0, ret; |
| 38 | |
| 39 | pagefault_disable(); |
| 40 | |
| 41 | switch (op) { |
| 42 | case FUTEX_OP_SET: |
| 43 | __futex_atomic_op("%1 = %4\n", ret, oldval, uaddr, oparg); |
| 44 | break; |
| 45 | case FUTEX_OP_ADD: |
| 46 | __futex_atomic_op("%1 = add(%0,%4)\n", ret, oldval, uaddr, |
| 47 | oparg); |
| 48 | break; |
| 49 | case FUTEX_OP_OR: |
| 50 | __futex_atomic_op("%1 = or(%0,%4)\n", ret, oldval, uaddr, |
| 51 | oparg); |
| 52 | break; |
| 53 | case FUTEX_OP_ANDN: |
| 54 | __futex_atomic_op("%1 = not(%4); %1 = and(%0,%1)\n", ret, |
| 55 | oldval, uaddr, oparg); |
| 56 | break; |
| 57 | case FUTEX_OP_XOR: |
| 58 | __futex_atomic_op("%1 = xor(%0,%4)\n", ret, oldval, uaddr, |
| 59 | oparg); |
| 60 | break; |
| 61 | default: |
| 62 | ret = -ENOSYS; |
| 63 | } |
| 64 | |
| 65 | pagefault_enable(); |
| 66 | |
| 67 | if (!ret) |
| 68 | *oval = oldval; |
| 69 | |
| 70 | return ret; |
| 71 | } |
| 72 | |
| 73 | static inline int |
| 74 | futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval, |
| 75 | u32 newval) |
| 76 | { |
| 77 | int prev; |
| 78 | int ret; |
| 79 | |
| 80 | if (!access_ok(uaddr, sizeof(u32))) |
| 81 | return -EFAULT; |
| 82 | |
| 83 | __asm__ __volatile__ ( |
| 84 | "1: %1 = memw_locked(%3)\n" |
| 85 | " {\n" |
| 86 | " p2 = cmp.eq(%1,%4)\n" |
| 87 | " if (!p2.new) jump:NT 3f\n" |
| 88 | " }\n" |
| 89 | "2: memw_locked(%3,p2) = %5\n" |
| 90 | " if (!p2) jump 1b\n" |
| 91 | "3:\n" |
| 92 | ".section .fixup,\"ax\"\n" |
| 93 | "4: %0 = #%6\n" |
| 94 | " jump 3b\n" |
| 95 | ".previous\n" |
| 96 | ".section __ex_table,\"a\"\n" |
| 97 | ".long 1b,4b,2b,4b\n" |
| 98 | ".previous\n" |
| 99 | : "+r" (ret), "=&r" (prev), "+m" (*uaddr) |
| 100 | : "r" (uaddr), "r" (oldval), "r" (newval), "i"(-EFAULT) |
| 101 | : "p2", "memory"); |
| 102 | |
| 103 | *uval = prev; |
| 104 | return ret; |
| 105 | } |
| 106 | |
| 107 | #endif /* __KERNEL__ */ |
| 108 | #endif /* _ASM_HEXAGON_FUTEX_H */ |