From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- arch/riscv/include/asm/futex.h | 104 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) create mode 100644 arch/riscv/include/asm/futex.h (limited to 'arch/riscv/include/asm/futex.h') diff --git a/arch/riscv/include/asm/futex.h b/arch/riscv/include/asm/futex.h new file mode 100644 index 0000000000..fc8130f995 --- /dev/null +++ b/arch/riscv/include/asm/futex.h @@ -0,0 +1,104 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2006 Ralf Baechle (ralf@linux-mips.org) + * Copyright (c) 2018 Jim Wilson (jimw@sifive.com) + */ + +#ifndef _ASM_RISCV_FUTEX_H +#define _ASM_RISCV_FUTEX_H + +#include +#include +#include +#include +#include + +/* We don't even really need the extable code, but for now keep it simple */ +#ifndef CONFIG_MMU +#define __enable_user_access() do { } while (0) +#define __disable_user_access() do { } while (0) +#endif + +#define __futex_atomic_op(insn, ret, oldval, uaddr, oparg) \ +{ \ + __enable_user_access(); \ + __asm__ __volatile__ ( \ + "1: " insn " \n" \ + "2: \n" \ + _ASM_EXTABLE_UACCESS_ERR(1b, 2b, %[r]) \ + : [r] "+r" (ret), [ov] "=&r" (oldval), \ + [u] "+m" (*uaddr) \ + : [op] "Jr" (oparg) \ + : "memory"); \ + __disable_user_access(); \ +} + +static inline int +arch_futex_atomic_op_inuser(int op, int oparg, int *oval, u32 __user *uaddr) +{ + int oldval = 0, ret = 0; + + if (!access_ok(uaddr, sizeof(u32))) + return -EFAULT; + + switch (op) { + case FUTEX_OP_SET: + __futex_atomic_op("amoswap.w.aqrl %[ov],%z[op],%[u]", + ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ADD: + __futex_atomic_op("amoadd.w.aqrl %[ov],%z[op],%[u]", + ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_OR: + __futex_atomic_op("amoor.w.aqrl %[ov],%z[op],%[u]", + ret, oldval, uaddr, oparg); + break; + case FUTEX_OP_ANDN: + __futex_atomic_op("amoand.w.aqrl %[ov],%z[op],%[u]", + ret, oldval, uaddr, ~oparg); + break; + case FUTEX_OP_XOR: + __futex_atomic_op("amoxor.w.aqrl %[ov],%z[op],%[u]", + ret, oldval, uaddr, oparg); + break; + default: + ret = -ENOSYS; + } + + 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; + uintptr_t tmp; + + if (!access_ok(uaddr, sizeof(u32))) + return -EFAULT; + + __enable_user_access(); + __asm__ __volatile__ ( + "1: lr.w.aqrl %[v],%[u] \n" + " bne %[v],%z[ov],3f \n" + "2: sc.w.aqrl %[t],%z[nv],%[u] \n" + " bnez %[t],1b \n" + "3: \n" + _ASM_EXTABLE_UACCESS_ERR(1b, 3b, %[r]) \ + _ASM_EXTABLE_UACCESS_ERR(2b, 3b, %[r]) \ + : [r] "+r" (ret), [v] "=&r" (val), [u] "+m" (*uaddr), [t] "=&r" (tmp) + : [ov] "Jr" (oldval), [nv] "Jr" (newval) + : "memory"); + __disable_user_access(); + + *uval = val; + return ret; +} + +#endif /* _ASM_RISCV_FUTEX_H */ -- cgit v1.2.3