From 04091d6c0535f6dc82af864ab56425235c6581a4 Mon Sep 17 00:00:00 2001 From: Nylon Chen Date: Mon, 30 Nov 2020 17:13:19 +0800 Subject: [PATCH] riscv: provide memmove implementation The memmove used by the kernel feature like KASAN. Signed-off-by: Nick Hu Signed-off-by: Nick Hu Signed-off-by: Nylon Chen Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/string.h | 8 ++--- arch/riscv/kernel/riscv_ksyms.c | 2 ++ arch/riscv/lib/Makefile | 1 + arch/riscv/lib/memmove.S | 64 +++++++++++++++++++++++++++++++++ 4 files changed, 71 insertions(+), 4 deletions(-) create mode 100644 arch/riscv/lib/memmove.S diff --git a/arch/riscv/include/asm/string.h b/arch/riscv/include/asm/string.h index 924af13f8555..5477e7ecb6e1 100644 --- a/arch/riscv/include/asm/string.h +++ b/arch/riscv/include/asm/string.h @@ -12,16 +12,16 @@ #define __HAVE_ARCH_MEMSET extern asmlinkage void *memset(void *, int, size_t); extern asmlinkage void *__memset(void *, int, size_t); - #define __HAVE_ARCH_MEMCPY extern asmlinkage void *memcpy(void *, const void *, size_t); extern asmlinkage void *__memcpy(void *, const void *, size_t); - +#define __HAVE_ARCH_MEMMOVE +extern asmlinkage void *memmove(void *, const void *, size_t); +extern asmlinkage void *__memmove(void *, const void *, size_t); /* For those files which don't want to check by kasan. */ #if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__) - #define memcpy(dst, src, len) __memcpy(dst, src, len) #define memset(s, c, n) __memset(s, c, n) - +#define memmove(dst, src, len) __memmove(dst, src, len) #endif #endif /* _ASM_RISCV_STRING_H */ diff --git a/arch/riscv/kernel/riscv_ksyms.c b/arch/riscv/kernel/riscv_ksyms.c index 450492e1cb4e..5ab1c7e1a6ed 100644 --- a/arch/riscv/kernel/riscv_ksyms.c +++ b/arch/riscv/kernel/riscv_ksyms.c @@ -11,5 +11,7 @@ */ EXPORT_SYMBOL(memset); EXPORT_SYMBOL(memcpy); +EXPORT_SYMBOL(memmove); EXPORT_SYMBOL(__memset); EXPORT_SYMBOL(__memcpy); +EXPORT_SYMBOL(__memmove); diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile index 47e7a8204460..ac6171e9c19e 100644 --- a/arch/riscv/lib/Makefile +++ b/arch/riscv/lib/Makefile @@ -2,5 +2,6 @@ lib-y += delay.o lib-y += memcpy.o lib-y += memset.o +lib-y += memmove.o lib-$(CONFIG_MMU) += uaccess.o lib-$(CONFIG_64BIT) += tishift.o diff --git a/arch/riscv/lib/memmove.S b/arch/riscv/lib/memmove.S new file mode 100644 index 000000000000..07d1d2152ba5 --- /dev/null +++ b/arch/riscv/lib/memmove.S @@ -0,0 +1,64 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#include +#include + +ENTRY(__memmove) +WEAK(memmove) + move t0, a0 + move t1, a1 + + beq a0, a1, exit_memcpy + beqz a2, exit_memcpy + srli t2, a2, 0x2 + + slt t3, a0, a1 + beqz t3, do_reverse + + andi a2, a2, 0x3 + li t4, 1 + beqz t2, byte_copy + +word_copy: + lw t3, 0(a1) + addi t2, t2, -1 + addi a1, a1, 4 + sw t3, 0(a0) + addi a0, a0, 4 + bnez t2, word_copy + beqz a2, exit_memcpy + j byte_copy + +do_reverse: + add a0, a0, a2 + add a1, a1, a2 + andi a2, a2, 0x3 + li t4, -1 + beqz t2, reverse_byte_copy + +reverse_word_copy: + addi a1, a1, -4 + addi t2, t2, -1 + lw t3, 0(a1) + addi a0, a0, -4 + sw t3, 0(a0) + bnez t2, reverse_word_copy + beqz a2, exit_memcpy + +reverse_byte_copy: + addi a0, a0, -1 + addi a1, a1, -1 + +byte_copy: + lb t3, 0(a1) + addi a2, a2, -1 + sb t3, 0(a0) + add a1, a1, t4 + add a0, a0, t4 + bnez a2, byte_copy + +exit_memcpy: + move a0, t0 + move a1, t1 + ret +END(__memmove)