1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_ASM_UACCESS_H
#define __ASM_ASM_UACCESS_H
#include <asm/alternative-macros.h>
#include <asm/asm-extable.h>
#include <asm/assembler.h>
#include <asm/kernel-pgtable.h>
#include <asm/mmu.h>
#include <asm/sysreg.h>
/*
* User access enabling/disabling macros.
*/
#ifdef CONFIG_ARM64_SW_TTBR0_PAN
.macro __uaccess_ttbr0_disable, tmp1
mrs \tmp1, ttbr1_el1 // swapper_pg_dir
bic \tmp1, \tmp1, #TTBR_ASID_MASK
sub \tmp1, \tmp1, #RESERVED_SWAPPER_OFFSET // reserved_pg_dir
msr ttbr0_el1, \tmp1 // set reserved TTBR0_EL1
isb
add \tmp1, \tmp1, #RESERVED_SWAPPER_OFFSET
msr ttbr1_el1, \tmp1 // set reserved ASID
isb
.endm
.macro __uaccess_ttbr0_enable, tmp1, tmp2
get_current_task \tmp1
ldr \tmp1, [\tmp1, #TSK_TI_TTBR0] // load saved TTBR0_EL1
mrs \tmp2, ttbr1_el1
extr \tmp2, \tmp2, \tmp1, #48
ror \tmp2, \tmp2, #16
msr ttbr1_el1, \tmp2 // set the active ASID
isb
msr ttbr0_el1, \tmp1 // set the non-PAN TTBR0_EL1
isb
.endm
.macro uaccess_ttbr0_disable, tmp1, tmp2
alternative_if_not ARM64_HAS_PAN
save_and_disable_irq \tmp2 // avoid preemption
__uaccess_ttbr0_disable \tmp1
restore_irq \tmp2
alternative_else_nop_endif
.endm
.macro uaccess_ttbr0_enable, tmp1, tmp2, tmp3
alternative_if_not ARM64_HAS_PAN
save_and_disable_irq \tmp3 // avoid preemption
__uaccess_ttbr0_enable \tmp1, \tmp2
restore_irq \tmp3
alternative_else_nop_endif
.endm
#else
.macro uaccess_ttbr0_disable, tmp1, tmp2
.endm
.macro uaccess_ttbr0_enable, tmp1, tmp2, tmp3
.endm
#endif
#define USER(l, x...) \
9999: x; \
_asm_extable 9999b, l
/*
* Generate the assembly for LDTR/STTR with exception table entries.
* This is complicated as there is no post-increment or pair versions of the
* unprivileged instructions, and USER() only works for single instructions.
*/
.macro user_ldp l, reg1, reg2, addr, post_inc
8888: ldtr \reg1, [\addr];
8889: ldtr \reg2, [\addr, #8];
add \addr, \addr, \post_inc;
_asm_extable 8888b,\l;
_asm_extable 8889b,\l;
.endm
.macro user_stp l, reg1, reg2, addr, post_inc
8888: sttr \reg1, [\addr];
8889: sttr \reg2, [\addr, #8];
add \addr, \addr, \post_inc;
_asm_extable 8888b,\l;
_asm_extable 8889b,\l;
.endm
.macro user_ldst l, inst, reg, addr, post_inc
8888: \inst \reg, [\addr];
add \addr, \addr, \post_inc;
_asm_extable 8888b,\l;
.endm
#endif
|
