diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/loongarch/include/asm/futex.h | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/loongarch/include/asm/futex.h')
-rw-r--r-- | arch/loongarch/include/asm/futex.h | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/futex.h b/arch/loongarch/include/asm/futex.h new file mode 100644 index 0000000000..042ca4448e --- /dev/null +++ b/arch/loongarch/include/asm/futex.h @@ -0,0 +1,94 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020-2022 Loongson Technology Corporation Limited + */ +#ifndef _ASM_FUTEX_H +#define _ASM_FUTEX_H + +#include <linux/futex.h> +#include <linux/uaccess.h> +#include <asm/asm-extable.h> +#include <asm/barrier.h> +#include <asm/errno.h> + +#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ +{ \ + __asm__ __volatile__( \ + "1: ll.w %1, %4 # __futex_atomic_op\n" \ + " " insn " \n" \ + "2: sc.w $t0, %2 \n" \ + " beqz $t0, 1b \n" \ + "3: \n" \ + _ASM_EXTABLE_UACCESS_ERR(1b, 3b, %0) \ + _ASM_EXTABLE_UACCESS_ERR(2b, 3b, %0) \ + : "=r" (ret), "=&r" (oldval), \ + "=ZC" (*uaddr) \ + : "0" (0), "ZC" (*uaddr), "Jr" (oparg) \ + : "memory", "t0"); \ +} + +static inline int +arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr) +{ + int oldval = 0, ret = 0; + + pagefault_disable(); + + switch (op) { + case FUTEX_OP_SET: + __futex_atomic_op("move $t0, %z5", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ADD: + __futex_atomic_op("add.w $t0, %1, %z5", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_OR: + __futex_atomic_op("or $t0, %1, %z5", ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ANDN: + __futex_atomic_op("and $t0, %1, %z5", ret, oldval, uaddr, ~oparg); + break; + case FUTEX_OP_XOR: + __futex_atomic_op("xor $t0, %1, %z5", ret, oldval, uaddr, oparg); + break; + default: + ret = -ENOSYS; + } + + pagefault_enable(); + + if (!ret) + *oval = oldval; + + return ret; +} + +static inline int +futex_atomic_cmpxchg_inatomic(u32 *uval, u32 __user *uaddr, u32 oldval, u32 newval) +{ + int ret = 0; + u32 val = 0; + + if (!access_ok(uaddr, sizeof(u32))) + return -EFAULT; + + __asm__ __volatile__( + "# futex_atomic_cmpxchg_inatomic \n" + "1: ll.w %1, %3 \n" + " bne %1, %z4, 3f \n" + " move $t0, %z5 \n" + "2: sc.w $t0, %2 \n" + " beqz $t0, 1b \n" + "3: \n" + __WEAK_LLSC_MB + _ASM_EXTABLE_UACCESS_ERR(1b, 3b, %0) + _ASM_EXTABLE_UACCESS_ERR(2b, 3b, %0) + : "+r" (ret), "=&r" (val), "=ZC" (*uaddr) + : "ZC" (*uaddr), "Jr" (oldval), "Jr" (newval) + : "memory", "t0"); + + *uval = val; + + return ret; +} + +#endif /* _ASM_FUTEX_H */ |