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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#include <asm/alternative-asm.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/asm-extable.h>
#include <asm/cpu.h>
#include <asm/export.h>
#include <asm/regdef.h>
.irp to, 0, 1, 2, 3, 4, 5, 6, 7
.L_fixup_handle_\to\():
addi.d a0, a2, (\to) * (-8)
jr ra
.endr
SYM_FUNC_START(__copy_user)
/*
* Some CPUs support hardware unaligned access
*/
ALTERNATIVE "b __copy_user_generic", \
"b __copy_user_fast", CPU_FEATURE_UAL
SYM_FUNC_END(__copy_user)
EXPORT_SYMBOL(__copy_user)
/*
* unsigned long __copy_user_generic(void *to, const void *from, size_t n)
*
* a0: to
* a1: from
* a2: n
*/
SYM_FUNC_START(__copy_user_generic)
beqz a2, 3f
1: ld.b t0, a1, 0
2: st.b t0, a0, 0
addi.d a0, a0, 1
addi.d a1, a1, 1
addi.d a2, a2, -1
bgtz a2, 1b
3: move a0, a2
jr ra
_asm_extable 1b, .L_fixup_handle_0
_asm_extable 2b, .L_fixup_handle_0
SYM_FUNC_END(__copy_user_generic)
/*
* unsigned long __copy_user_fast(void *to, const void *from, unsigned long n)
*
* a0: to
* a1: from
* a2: n
*/
SYM_FUNC_START(__copy_user_fast)
beqz a2, 19f
ori a3, zero, 64
blt a2, a3, 17f
/* copy 64 bytes at a time */
1: ld.d t0, a1, 0
2: ld.d t1, a1, 8
3: ld.d t2, a1, 16
4: ld.d t3, a1, 24
5: ld.d t4, a1, 32
6: ld.d t5, a1, 40
7: ld.d t6, a1, 48
8: ld.d t7, a1, 56
9: st.d t0, a0, 0
10: st.d t1, a0, 8
11: st.d t2, a0, 16
12: st.d t3, a0, 24
13: st.d t4, a0, 32
14: st.d t5, a0, 40
15: st.d t6, a0, 48
16: st.d t7, a0, 56
addi.d a0, a0, 64
addi.d a1, a1, 64
addi.d a2, a2, -64
bge a2, a3, 1b
beqz a2, 19f
/* copy the remaining bytes */
17: ld.b t0, a1, 0
18: st.b t0, a0, 0
addi.d a0, a0, 1
addi.d a1, a1, 1
addi.d a2, a2, -1
bgt a2, zero, 17b
/* return */
19: move a0, a2
jr ra
/* fixup and ex_table */
_asm_extable 1b, .L_fixup_handle_0
_asm_extable 2b, .L_fixup_handle_1
_asm_extable 3b, .L_fixup_handle_2
_asm_extable 4b, .L_fixup_handle_3
_asm_extable 5b, .L_fixup_handle_4
_asm_extable 6b, .L_fixup_handle_5
_asm_extable 7b, .L_fixup_handle_6
_asm_extable 8b, .L_fixup_handle_7
_asm_extable 9b, .L_fixup_handle_0
_asm_extable 10b, .L_fixup_handle_1
_asm_extable 11b, .L_fixup_handle_2
_asm_extable 12b, .L_fixup_handle_3
_asm_extable 13b, .L_fixup_handle_4
_asm_extable 14b, .L_fixup_handle_5
_asm_extable 15b, .L_fixup_handle_6
_asm_extable 16b, .L_fixup_handle_7
_asm_extable 17b, .L_fixup_handle_0
_asm_extable 18b, .L_fixup_handle_0
SYM_FUNC_END(__copy_user_fast)
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