Unverified Commit 04091d6c authored by Nylon Chen's avatar Nylon Chen Committed by Palmer Dabbelt
Browse files

riscv: provide memmove implementation 



The memmove used by the kernel feature like KASAN.

Signed-off-by: default avatarNick Hu <nickhu@andestech.com>
Signed-off-by: default avatarNick Hu <nick650823@gmail.com>
Signed-off-by: default avatarNylon Chen <nylon7@andestech.com>
Signed-off-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
parent b5b11a8a

arch/riscv/include/asm/string.h

+4 −4
Original line number Diff line number Diff line
@@ -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 */

arch/riscv/kernel/riscv_ksyms.c

+2 −0
Original line number Diff line number Diff line
@@ -11,5 +11,7 @@ 
 */

EXPORT_SYMBOL(memset);

EXPORT_SYMBOL(memcpy);

EXPORT_SYMBOL(memmove);

EXPORT_SYMBOL(__memset);

EXPORT_SYMBOL(__memcpy);

EXPORT_SYMBOL(__memmove);

arch/riscv/lib/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -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

arch/riscv/lib/memmove.S

0 → 100644
+64 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */



#include <linux/linkage.h>

#include <asm/asm.h>



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)