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
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
|
// SPDX-License-Identifier: GPL-2.0+
#include <linux/kernel.h>
#include <linux/uaccess.h>
#include <linux/sched.h>
#include <asm/hw_breakpoint.h>
#include <asm/sstep.h>
#include <asm/cache.h>
static bool dar_in_user_range(unsigned long dar, struct arch_hw_breakpoint *info)
{
return ((info->address <= dar) && (dar - info->address < info->len));
}
static bool ea_user_range_overlaps(unsigned long ea, int size,
struct arch_hw_breakpoint *info)
{
return ((ea < info->address + info->len) &&
(ea + size > info->address));
}
static bool dar_in_hw_range(unsigned long dar, struct arch_hw_breakpoint *info)
{
unsigned long hw_start_addr, hw_end_addr;
hw_start_addr = ALIGN_DOWN(info->address, HW_BREAKPOINT_SIZE);
hw_end_addr = ALIGN(info->address + info->len, HW_BREAKPOINT_SIZE);
return ((hw_start_addr <= dar) && (hw_end_addr > dar));
}
static bool ea_hw_range_overlaps(unsigned long ea, int size,
struct arch_hw_breakpoint *info)
{
unsigned long hw_start_addr, hw_end_addr;
unsigned long align_size = HW_BREAKPOINT_SIZE;
/*
* On p10 predecessors, quadword is handle differently then
* other instructions.
*/
if (!cpu_has_feature(CPU_FTR_ARCH_31) && size == 16)
align_size = HW_BREAKPOINT_SIZE_QUADWORD;
hw_start_addr = ALIGN_DOWN(info->address, align_size);
hw_end_addr = ALIGN(info->address + info->len, align_size);
return ((ea < hw_end_addr) && (ea + size > hw_start_addr));
}
/*
* If hw has multiple DAWR registers, we also need to check all
* dawrx constraint bits to confirm this is _really_ a valid event.
* If type is UNKNOWN, but privilege level matches, consider it as
* a positive match.
*/
static bool check_dawrx_constraints(struct pt_regs *regs, int type,
struct arch_hw_breakpoint *info)
{
if (OP_IS_LOAD(type) && !(info->type & HW_BRK_TYPE_READ))
return false;
/*
* The Cache Management instructions other than dcbz never
* cause a match. i.e. if type is CACHEOP, the instruction
* is dcbz, and dcbz is treated as Store.
*/
if ((OP_IS_STORE(type) || type == CACHEOP) && !(info->type & HW_BRK_TYPE_WRITE))
return false;
if (is_kernel_addr(regs->nip) && !(info->type & HW_BRK_TYPE_KERNEL))
return false;
if (user_mode(regs) && !(info->type & HW_BRK_TYPE_USER))
return false;
return true;
}
/*
* Return true if the event is valid wrt dawr configuration,
* including extraneous exception. Otherwise return false.
*/
bool wp_check_constraints(struct pt_regs *regs, ppc_inst_t instr,
unsigned long ea, int type, int size,
struct arch_hw_breakpoint *info)
{
bool in_user_range = dar_in_user_range(regs->dar, info);
bool dawrx_constraints;
/*
* 8xx supports only one breakpoint and thus we can
* unconditionally return true.
*/
if (IS_ENABLED(CONFIG_PPC_8xx)) {
if (!in_user_range)
info->type |= HW_BRK_TYPE_EXTRANEOUS_IRQ;
return true;
}
if (unlikely(ppc_inst_equal(instr, ppc_inst(0)))) {
if (cpu_has_feature(CPU_FTR_ARCH_31) &&
!dar_in_hw_range(regs->dar, info))
return false;
return true;
}
dawrx_constraints = check_dawrx_constraints(regs, type, info);
if (type == UNKNOWN) {
if (cpu_has_feature(CPU_FTR_ARCH_31) &&
!dar_in_hw_range(regs->dar, info))
return false;
return dawrx_constraints;
}
if (ea_user_range_overlaps(ea, size, info))
return dawrx_constraints;
if (ea_hw_range_overlaps(ea, size, info)) {
if (dawrx_constraints) {
info->type |= HW_BRK_TYPE_EXTRANEOUS_IRQ;
return true;
}
}
return false;
}
void wp_get_instr_detail(struct pt_regs *regs, ppc_inst_t *instr,
int *type, int *size, unsigned long *ea)
{
struct instruction_op op;
int err;
pagefault_disable();
err = __get_user_instr(*instr, (void __user *)regs->nip);
pagefault_enable();
if (err)
return;
analyse_instr(&op, regs, *instr);
*type = GETTYPE(op.type);
*ea = op.ea;
if (!(regs->msr & MSR_64BIT))
*ea &= 0xffffffffUL;
*size = GETSIZE(op.type);
if (*type == CACHEOP) {
*size = l1_dcache_bytes();
*ea &= ~(*size - 1);
} else if (*type == LOAD_VMX || *type == STORE_VMX) {
*ea &= ~(*size - 1);
}
}
|
