summaryrefslogtreecommitdiff
path: root/arch/arm/include/asm/ptrace.h
blob: 51622ba7c4a66a91494ecc49be4520fd4b14df88 (plain)
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
159
160
161
162
/*
 *  arch/arm/include/asm/ptrace.h
 *
 *  Copyright (C) 1996-2003 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#ifndef __ASM_ARM_PTRACE_H
#define __ASM_ARM_PTRACE_H

#include <uapi/asm/ptrace.h>

#ifndef __ASSEMBLY__
struct pt_regs {
	unsigned long uregs[18];
};

#define user_mode(regs)	\
	(((regs)->ARM_cpsr & 0xf) == 0)

#ifdef CONFIG_ARM_THUMB
#define thumb_mode(regs) \
	(((regs)->ARM_cpsr & PSR_T_BIT))
#else
#define thumb_mode(regs) (0)
#endif

#ifndef CONFIG_CPU_V7M
#define isa_mode(regs) \
	((((regs)->ARM_cpsr & PSR_J_BIT) >> (__ffs(PSR_J_BIT) - 1)) | \
	 (((regs)->ARM_cpsr & PSR_T_BIT) >> (__ffs(PSR_T_BIT))))
#else
#define isa_mode(regs) 1 /* Thumb */
#endif

#define processor_mode(regs) \
	((regs)->ARM_cpsr & MODE_MASK)

#define interrupts_enabled(regs) \
	(!((regs)->ARM_cpsr & PSR_I_BIT))

#define fast_interrupts_enabled(regs) \
	(!((regs)->ARM_cpsr & PSR_F_BIT))

/* Are the current registers suitable for user mode?
 * (used to maintain security in signal handlers)
 */
static inline int valid_user_regs(struct pt_regs *regs)
{
#ifndef CONFIG_CPU_V7M
	unsigned long mode = regs->ARM_cpsr & MODE_MASK;

	/*
	 * Always clear the F (FIQ) and A (delayed abort) bits
	 */
	regs->ARM_cpsr &= ~(PSR_F_BIT | PSR_A_BIT);

	if ((regs->ARM_cpsr & PSR_I_BIT) == 0) {
		if (mode == USR_MODE)
			return 1;
		if (elf_hwcap & HWCAP_26BIT && mode == USR26_MODE)
			return 1;
	}

	/*
	 * Force CPSR to something logical...
	 */
	regs->ARM_cpsr &= PSR_f | PSR_s | PSR_x | PSR_T_BIT | MODE32_BIT;
	if (!(elf_hwcap & HWCAP_26BIT))
		regs->ARM_cpsr |= USR_MODE;

	return 0;
#else /* ifndef CONFIG_CPU_V7M */
	return 1;
#endif
}

static inline long regs_return_value(struct pt_regs *regs)
{
	return regs->ARM_r0;
}

#define instruction_pointer(regs)	(regs)->ARM_pc

#ifdef CONFIG_THUMB2_KERNEL
#define frame_pointer(regs) (regs)->ARM_r7
#else
#define frame_pointer(regs) (regs)->ARM_fp
#endif

static inline void instruction_pointer_set(struct pt_regs *regs,
					   unsigned long val)
{
	instruction_pointer(regs) = val;
}

#ifdef CONFIG_SMP
extern unsigned long profile_pc(struct pt_regs *regs);
#else
#define profile_pc(regs) instruction_pointer(regs)
#endif

#define predicate(x)		((x) & 0xf0000000)
#define PREDICATE_ALWAYS	0xe0000000

/*
 * True if instr is a 32-bit thumb instruction. This works if instr
 * is the first or only half-word of a thumb instruction. It also works
 * when instr holds all 32-bits of a wide thumb instruction if stored
 * in the form (first_half<<16)|(second_half)
 */
#define is_wide_instruction(instr)	((unsigned)(instr) >= 0xe800)

/*
 * kprobe-based event tracer support
 */
#include <linux/stddef.h>
#include <linux/types.h>
#define MAX_REG_OFFSET (offsetof(struct pt_regs, ARM_ORIG_r0))

extern int regs_query_register_offset(const char *name);
extern const char *regs_query_register_name(unsigned int offset);
extern bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr);
extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
					       unsigned int n);

/**
 * regs_get_register() - get register value from its offset
 * @regs:	   pt_regs from which register value is gotten
 * @offset:    offset number of the register.
 *
 * regs_get_register returns the value of a register whose offset from @regs.
 * The @offset is the offset of the register in struct pt_regs.
 * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
 */
static inline unsigned long regs_get_register(struct pt_regs *regs,
					      unsigned int offset)
{
	if (unlikely(offset > MAX_REG_OFFSET))
		return 0;
	return *(unsigned long *)((unsigned long)regs + offset);
}

/* Valid only for Kernel mode traps. */
static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
{
	return regs->ARM_sp;
}

static inline unsigned long user_stack_pointer(struct pt_regs *regs)
{
	return regs->ARM_sp;
}

#define current_pt_regs(void) ({ (struct pt_regs *)			\
		((current_stack_pointer | (THREAD_SIZE - 1)) - 7) - 1;	\
})

#endif /* __ASSEMBLY__ */
#endif