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linux/arch/loongarch/lib/copy_user.S
Tiezhu Yang cb8a2ef084 LoongArch: Add ORC stack unwinder support
The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is
similar in concept to a DWARF unwinder. The difference is that the format
of the ORC data is much simpler than DWARF, which in turn allows the ORC
unwinder to be much simpler and faster.

The ORC data consists of unwind tables which are generated by objtool.
After analyzing all the code paths of a .o file, it determines information
about the stack state at each instruction address in the file and outputs
that information to the .orc_unwind and .orc_unwind_ip sections.

The per-object ORC sections are combined at link time and are sorted and
post-processed at boot time. The unwinder uses the resulting data to
correlate instruction addresses with their stack states at run time.

Most of the logic are similar with x86, in order to get ra info before ra
is saved into stack, add ra_reg and ra_offset into orc_entry. At the same
time, modify some arch-specific code to silence the objtool warnings.

Co-developed-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Co-developed-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-03-11 22:23:47 +08:00

284 lines
5.3 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#include <linux/export.h>
#include <asm/alternative-asm.h>
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/asm-extable.h>
#include <asm/cpu.h>
#include <asm/regdef.h>
#include <asm/unwind_hints.h>
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, 3b
_asm_extable 2b, 3b
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)
sltui t0, a2, 9
bnez t0, .Lsmall
0: ld.d t0, a1, 0
1: st.d t0, a0, 0
add.d a3, a1, a2
add.d a2, a0, a2
/* align up destination address */
andi t1, a0, 7
sub.d t0, zero, t1
addi.d t0, t0, 8
add.d a1, a1, t0
add.d a0, a0, t0
addi.d a4, a3, -64
bgeu a1, a4, .Llt64
/* copy 64 bytes at a time */
.Lloop64:
2: ld.d t0, a1, 0
3: ld.d t1, a1, 8
4: ld.d t2, a1, 16
5: ld.d t3, a1, 24
6: ld.d t4, a1, 32
7: ld.d t5, a1, 40
8: ld.d t6, a1, 48
9: ld.d t7, a1, 56
10: st.d t0, a0, 0
11: st.d t1, a0, 8
12: st.d t2, a0, 16
13: st.d t3, a0, 24
14: st.d t4, a0, 32
15: st.d t5, a0, 40
16: st.d t6, a0, 48
17: st.d t7, a0, 56
addi.d a1, a1, 64
addi.d a0, a0, 64
bltu a1, a4, .Lloop64
/* copy the remaining bytes */
.Llt64:
addi.d a4, a3, -32
bgeu a1, a4, .Llt32
18: ld.d t0, a1, 0
19: ld.d t1, a1, 8
20: ld.d t2, a1, 16
21: ld.d t3, a1, 24
22: st.d t0, a0, 0
23: st.d t1, a0, 8
24: st.d t2, a0, 16
25: st.d t3, a0, 24
addi.d a1, a1, 32
addi.d a0, a0, 32
.Llt32:
addi.d a4, a3, -16
bgeu a1, a4, .Llt16
26: ld.d t0, a1, 0
27: ld.d t1, a1, 8
28: st.d t0, a0, 0
29: st.d t1, a0, 8
addi.d a1, a1, 16
addi.d a0, a0, 16
.Llt16:
addi.d a4, a3, -8
bgeu a1, a4, .Llt8
30: ld.d t0, a1, 0
31: st.d t0, a0, 0
addi.d a1, a1, 8
addi.d a0, a0, 8
.Llt8:
32: ld.d t0, a3, -8
33: st.d t0, a2, -8
/* return */
move a0, zero
jr ra
.align 5
.Lsmall:
pcaddi t0, 8
slli.d a3, a2, 5
add.d t0, t0, a3
jr t0
.align 5
move a0, zero
jr ra
.align 5
34: ld.b t0, a1, 0
35: st.b t0, a0, 0
move a0, zero
jr ra
.align 5
36: ld.h t0, a1, 0
37: st.h t0, a0, 0
move a0, zero
jr ra
.align 5
38: ld.h t0, a1, 0
39: ld.b t1, a1, 2
40: st.h t0, a0, 0
41: st.b t1, a0, 2
move a0, zero
jr ra
.align 5
42: ld.w t0, a1, 0
43: st.w t0, a0, 0
move a0, zero
jr ra
.align 5
44: ld.w t0, a1, 0
45: ld.b t1, a1, 4
46: st.w t0, a0, 0
47: st.b t1, a0, 4
move a0, zero
jr ra
.align 5
48: ld.w t0, a1, 0
49: ld.h t1, a1, 4
50: st.w t0, a0, 0
51: st.h t1, a0, 4
move a0, zero
jr ra
.align 5
52: ld.w t0, a1, 0
53: ld.w t1, a1, 3
54: st.w t0, a0, 0
55: st.w t1, a0, 3
move a0, zero
jr ra
.align 5
56: ld.d t0, a1, 0
57: st.d t0, a0, 0
move a0, zero
jr ra
/* fixup and ex_table */
.Llarge_fixup:
sub.d a2, a2, a0
.Lsmall_fixup:
58: ld.b t0, a1, 0
59: st.b t0, a0, 0
addi.d a0, a0, 1
addi.d a1, a1, 1
addi.d a2, a2, -1
bgt a2, zero, 58b
.Lexit:
move a0, a2
jr ra
_asm_extable 0b, .Lsmall_fixup
_asm_extable 1b, .Lsmall_fixup
_asm_extable 2b, .Llarge_fixup
_asm_extable 3b, .Llarge_fixup
_asm_extable 4b, .Llarge_fixup
_asm_extable 5b, .Llarge_fixup
_asm_extable 6b, .Llarge_fixup
_asm_extable 7b, .Llarge_fixup
_asm_extable 8b, .Llarge_fixup
_asm_extable 9b, .Llarge_fixup
_asm_extable 10b, .Llarge_fixup
_asm_extable 11b, .Llarge_fixup
_asm_extable 12b, .Llarge_fixup
_asm_extable 13b, .Llarge_fixup
_asm_extable 14b, .Llarge_fixup
_asm_extable 15b, .Llarge_fixup
_asm_extable 16b, .Llarge_fixup
_asm_extable 17b, .Llarge_fixup
_asm_extable 18b, .Llarge_fixup
_asm_extable 19b, .Llarge_fixup
_asm_extable 20b, .Llarge_fixup
_asm_extable 21b, .Llarge_fixup
_asm_extable 22b, .Llarge_fixup
_asm_extable 23b, .Llarge_fixup
_asm_extable 24b, .Llarge_fixup
_asm_extable 25b, .Llarge_fixup
_asm_extable 26b, .Llarge_fixup
_asm_extable 27b, .Llarge_fixup
_asm_extable 28b, .Llarge_fixup
_asm_extable 29b, .Llarge_fixup
_asm_extable 30b, .Llarge_fixup
_asm_extable 31b, .Llarge_fixup
_asm_extable 32b, .Llarge_fixup
_asm_extable 33b, .Llarge_fixup
_asm_extable 34b, .Lexit
_asm_extable 35b, .Lexit
_asm_extable 36b, .Lsmall_fixup
_asm_extable 37b, .Lsmall_fixup
_asm_extable 38b, .Lsmall_fixup
_asm_extable 39b, .Lsmall_fixup
_asm_extable 40b, .Lsmall_fixup
_asm_extable 41b, .Lsmall_fixup
_asm_extable 42b, .Lsmall_fixup
_asm_extable 43b, .Lsmall_fixup
_asm_extable 44b, .Lsmall_fixup
_asm_extable 45b, .Lsmall_fixup
_asm_extable 46b, .Lsmall_fixup
_asm_extable 47b, .Lsmall_fixup
_asm_extable 48b, .Lsmall_fixup
_asm_extable 49b, .Lsmall_fixup
_asm_extable 50b, .Lsmall_fixup
_asm_extable 51b, .Lsmall_fixup
_asm_extable 52b, .Lsmall_fixup
_asm_extable 53b, .Lsmall_fixup
_asm_extable 54b, .Lsmall_fixup
_asm_extable 55b, .Lsmall_fixup
_asm_extable 56b, .Lsmall_fixup
_asm_extable 57b, .Lsmall_fixup
_asm_extable 58b, .Lexit
_asm_extable 59b, .Lexit
SYM_FUNC_END(__copy_user_fast)
STACK_FRAME_NON_STANDARD __copy_user_fast