17153c3cbSHuacai Chen /* SPDX-License-Identifier: GPL-2.0 */
27153c3cbSHuacai Chen /*
37153c3cbSHuacai Chen * Copyright (C) 2020-2022 Loongson Technology Corporation Limited
47153c3cbSHuacai Chen */
57153c3cbSHuacai Chen #ifndef _ASM_FUTEX_H
67153c3cbSHuacai Chen #define _ASM_FUTEX_H
77153c3cbSHuacai Chen
87153c3cbSHuacai Chen #include <linux/futex.h>
97153c3cbSHuacai Chen #include <linux/uaccess.h>
10508f28c6SYouling Tang #include <asm/asm-extable.h>
117153c3cbSHuacai Chen #include <asm/barrier.h>
127153c3cbSHuacai Chen #include <asm/errno.h>
137153c3cbSHuacai Chen
147153c3cbSHuacai Chen #define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \
157153c3cbSHuacai Chen { \
167153c3cbSHuacai Chen __asm__ __volatile__( \
177153c3cbSHuacai Chen "1: ll.w %1, %4 # __futex_atomic_op\n" \
187153c3cbSHuacai Chen " " insn " \n" \
197153c3cbSHuacai Chen "2: sc.w $t0, %2 \n" \
20d47b2dc8SWANG Xuerui " beqz $t0, 1b \n" \
217153c3cbSHuacai Chen "3: \n" \
22*672999cfSYouling Tang _ASM_EXTABLE_UACCESS_ERR(1b, 3b, %0) \
23*672999cfSYouling Tang _ASM_EXTABLE_UACCESS_ERR(2b, 3b, %0) \
247153c3cbSHuacai Chen : "=r" (ret), "=&r" (oldval), \
257153c3cbSHuacai Chen "=ZC" (*uaddr) \
26*672999cfSYouling Tang : "0" (0), "ZC" (*uaddr), "Jr" (oparg) \
277153c3cbSHuacai Chen : "memory", "t0"); \
287153c3cbSHuacai Chen }
297153c3cbSHuacai Chen
307153c3cbSHuacai Chen static inline int
arch_futex_atomic_op_inuser(int op,int oparg,int * oval,u32 __user * uaddr)317153c3cbSHuacai Chen arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr)
327153c3cbSHuacai Chen {
337153c3cbSHuacai Chen int oldval = 0, ret = 0;
347153c3cbSHuacai Chen
357153c3cbSHuacai Chen pagefault_disable();
367153c3cbSHuacai Chen
377153c3cbSHuacai Chen switch (op) {
387153c3cbSHuacai Chen case FUTEX_OP_SET:
397153c3cbSHuacai Chen __futex_atomic_op("move $t0, %z5", ret, oldval, uaddr, oparg);
407153c3cbSHuacai Chen break;
417153c3cbSHuacai Chen case FUTEX_OP_ADD:
427153c3cbSHuacai Chen __futex_atomic_op("add.w $t0, %1, %z5", ret, oldval, uaddr, oparg);
437153c3cbSHuacai Chen break;
447153c3cbSHuacai Chen case FUTEX_OP_OR:
457153c3cbSHuacai Chen __futex_atomic_op("or $t0, %1, %z5", ret, oldval, uaddr, oparg);
467153c3cbSHuacai Chen break;
477153c3cbSHuacai Chen case FUTEX_OP_ANDN:
487153c3cbSHuacai Chen __futex_atomic_op("and $t0, %1, %z5", ret, oldval, uaddr, ~oparg);
497153c3cbSHuacai Chen break;
507153c3cbSHuacai Chen case FUTEX_OP_XOR:
517153c3cbSHuacai Chen __futex_atomic_op("xor $t0, %1, %z5", ret, oldval, uaddr, oparg);
527153c3cbSHuacai Chen break;
537153c3cbSHuacai Chen default:
547153c3cbSHuacai Chen ret = -ENOSYS;
557153c3cbSHuacai Chen }
567153c3cbSHuacai Chen
577153c3cbSHuacai Chen pagefault_enable();
587153c3cbSHuacai Chen
597153c3cbSHuacai Chen if (!ret)
607153c3cbSHuacai Chen *oval = oldval;
617153c3cbSHuacai Chen
627153c3cbSHuacai Chen return ret;
637153c3cbSHuacai Chen }
647153c3cbSHuacai Chen
657153c3cbSHuacai Chen static inline int
futex_atomic_cmpxchg_inatomic(u32 * uval,u32 __user * uaddr,u32 oldval,u32 newval)667153c3cbSHuacai Chen futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval, u32 newval)
677153c3cbSHuacai Chen {
687153c3cbSHuacai Chen int ret = 0;
697153c3cbSHuacai Chen u32 val = 0;
707153c3cbSHuacai Chen
717153c3cbSHuacai Chen if (!access_ok(uaddr, sizeof(u32)))
727153c3cbSHuacai Chen return -EFAULT;
737153c3cbSHuacai Chen
747153c3cbSHuacai Chen __asm__ __volatile__(
757153c3cbSHuacai Chen "# futex_atomic_cmpxchg_inatomic \n"
767153c3cbSHuacai Chen "1: ll.w %1, %3 \n"
777153c3cbSHuacai Chen " bne %1, %z4, 3f \n"
7857ce5d3eSWANG Xuerui " move $t0, %z5 \n"
797153c3cbSHuacai Chen "2: sc.w $t0, %2 \n"
80d47b2dc8SWANG Xuerui " beqz $t0, 1b \n"
817153c3cbSHuacai Chen "3: \n"
8246859ac8SHuacai Chen __WEAK_LLSC_MB
83*672999cfSYouling Tang _ASM_EXTABLE_UACCESS_ERR(1b, 3b, %0)
84*672999cfSYouling Tang _ASM_EXTABLE_UACCESS_ERR(2b, 3b, %0)
85f62b7626SJun Yi : "+r" (ret), "=&r" (val), "=ZC" (*uaddr)
86*672999cfSYouling Tang : "ZC" (*uaddr), "Jr" (oldval), "Jr" (newval)
877153c3cbSHuacai Chen : "memory", "t0");
887153c3cbSHuacai Chen
897153c3cbSHuacai Chen *uval = val;
907153c3cbSHuacai Chen
917153c3cbSHuacai Chen return ret;
927153c3cbSHuacai Chen }
937153c3cbSHuacai Chen
947153c3cbSHuacai Chen #endif /* _ASM_FUTEX_H */
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