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author | Huacai Chen <chenhuacai@loongson.cn> | 2022-05-31 13:04:11 +0300 |
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committer | Huacai Chen <chenhuacai@loongson.cn> | 2022-06-03 15:09:28 +0300 |
commit | 7153c3cbb5b9b99755659b97861fd4fc909ed86f (patch) | |
tree | 307ba0baa2827ac8426e032cab988e29eb6d55cd /arch/loongarch/include/asm/futex.h | |
parent | fcdfe9d22bed08409968a751e93112f742208be6 (diff) | |
download | linux-7153c3cbb5b9b99755659b97861fd4fc909ed86f.tar.xz |
LoongArch: Add misc common routines
Add some misc common routines for LoongArch, including: asm-offsets
routines, futex functions, i/o memory access functions, frame-buffer
functions, procfs information display, etc.
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Diffstat (limited to 'arch/loongarch/include/asm/futex.h')
-rw-r--r-- | arch/loongarch/include/asm/futex.h | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/arch/loongarch/include/asm/futex.h b/arch/loongarch/include/asm/futex.h new file mode 100644 index 000000000000..b27d55f92db7 --- /dev/null +++ b/arch/loongarch/include/asm/futex.h @@ -0,0 +1,107 @@ +/* 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/barrier.h> +#include <asm/compiler.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" \ + " beq $t0, $zero, 1b \n" \ + "3: \n" \ + " .section .fixup,\"ax\" \n" \ + "4: li.w %0, %6 \n" \ + " b 3b \n" \ + " .previous \n" \ + " .section __ex_table,\"a\" \n" \ + " "__UA_ADDR "\t1b, 4b \n" \ + " "__UA_ADDR "\t2b, 4b \n" \ + " .previous \n" \ + : "=r" (ret), "=&r" (oldval), \ + "=ZC" (*uaddr) \ + : "0" (0), "ZC" (*uaddr), "Jr" (oparg), \ + "i" (-EFAULT) \ + : "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" + " or $t0, %z5, $zero \n" + "2: sc.w $t0, %2 \n" + " beq $zero, $t0, 1b \n" + "3: \n" + " .section .fixup,\"ax\" \n" + "4: li.d %0, %6 \n" + " b 3b \n" + " .previous \n" + " .section __ex_table,\"a\" \n" + " "__UA_ADDR "\t1b, 4b \n" + " "__UA_ADDR "\t2b, 4b \n" + " .previous \n" + : "+r" (ret), "=&r" (val), "=" GCC_OFF_SMALL_ASM() (*uaddr) + : GCC_OFF_SMALL_ASM() (*uaddr), "Jr" (oldval), "Jr" (newval), + "i" (-EFAULT) + : "memory", "t0"); + + *uval = val; + + return ret; +} + +#endif /* _ASM_FUTEX_H */ |