1 /*
2 * arch/arm/include/asm/ptrace.h
3 *
4 * Copyright (C) 1996-2003 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10 #ifndef __ASM_ARM_PTRACE_H
11 #define __ASM_ARM_PTRACE_H
12
13 #include <uapi/asm/ptrace.h>
14
15 #ifndef __ASSEMBLY__
16 #include <linux/types.h>
17
18 struct pt_regs {
19 unsigned long uregs[18];
20 };
21
22 struct svc_pt_regs {
23 struct pt_regs regs;
24 u32 dacr;
25 u32 addr_limit;
26 };
27
28 #define to_svc_pt_regs(r) container_of(r, struct svc_pt_regs, regs)
29
30 #define user_mode(regs) \
31 (((regs)->ARM_cpsr & 0xf) == 0)
32
33 #ifdef CONFIG_ARM_THUMB
34 #define thumb_mode(regs) \
35 (((regs)->ARM_cpsr & PSR_T_BIT))
36 #else
37 #define thumb_mode(regs) (0)
38 #endif
39
40 #ifndef CONFIG_CPU_V7M
41 #define isa_mode(regs) \
42 ((((regs)->ARM_cpsr & PSR_J_BIT) >> (__ffs(PSR_J_BIT) - 1)) | \
43 (((regs)->ARM_cpsr & PSR_T_BIT) >> (__ffs(PSR_T_BIT))))
44 #else
45 #define isa_mode(regs) 1 /* Thumb */
46 #endif
47
48 #define processor_mode(regs) \
49 ((regs)->ARM_cpsr & MODE_MASK)
50
51 #define interrupts_enabled(regs) \
52 (!((regs)->ARM_cpsr & PSR_I_BIT))
53
54 #define fast_interrupts_enabled(regs) \
55 (!((regs)->ARM_cpsr & PSR_F_BIT))
56
57 /* Are the current registers suitable for user mode?
58 * (used to maintain security in signal handlers)
59 */
valid_user_regs(struct pt_regs * regs)60 static inline int valid_user_regs(struct pt_regs *regs)
61 {
62 #ifndef CONFIG_CPU_V7M
63 unsigned long mode = regs->ARM_cpsr & MODE_MASK;
64
65 /*
66 * Always clear the F (FIQ) and A (delayed abort) bits
67 */
68 regs->ARM_cpsr &= ~(PSR_F_BIT | PSR_A_BIT);
69
70 if ((regs->ARM_cpsr & PSR_I_BIT) == 0) {
71 if (mode == USR_MODE)
72 return 1;
73 if (elf_hwcap & HWCAP_26BIT && mode == USR26_MODE)
74 return 1;
75 }
76
77 /*
78 * Force CPSR to something logical...
79 */
80 regs->ARM_cpsr &= PSR_f | PSR_s | PSR_x | PSR_T_BIT | MODE32_BIT;
81 if (!(elf_hwcap & HWCAP_26BIT))
82 regs->ARM_cpsr |= USR_MODE;
83
84 return 0;
85 #else /* ifndef CONFIG_CPU_V7M */
86 return 1;
87 #endif
88 }
89
regs_return_value(struct pt_regs * regs)90 static inline long regs_return_value(struct pt_regs *regs)
91 {
92 return regs->ARM_r0;
93 }
94
95 #define instruction_pointer(regs) (regs)->ARM_pc
96
97 #ifdef CONFIG_THUMB2_KERNEL
98 #define frame_pointer(regs) (regs)->ARM_r7
99 #else
100 #define frame_pointer(regs) (regs)->ARM_fp
101 #endif
102
instruction_pointer_set(struct pt_regs * regs,unsigned long val)103 static inline void instruction_pointer_set(struct pt_regs *regs,
104 unsigned long val)
105 {
106 instruction_pointer(regs) = val;
107 }
108
109 #ifdef CONFIG_SMP
110 extern unsigned long profile_pc(struct pt_regs *regs);
111 #else
112 #define profile_pc(regs) instruction_pointer(regs)
113 #endif
114
115 #define predicate(x) ((x) & 0xf0000000)
116 #define PREDICATE_ALWAYS 0xe0000000
117
118 /*
119 * True if instr is a 32-bit thumb instruction. This works if instr
120 * is the first or only half-word of a thumb instruction. It also works
121 * when instr holds all 32-bits of a wide thumb instruction if stored
122 * in the form (first_half<<16)|(second_half)
123 */
124 #define is_wide_instruction(instr) ((unsigned)(instr) >= 0xe800)
125
126 /*
127 * kprobe-based event tracer support
128 */
129 #include <linux/compiler.h>
130 #define MAX_REG_OFFSET (offsetof(struct pt_regs, ARM_ORIG_r0))
131
132 extern int regs_query_register_offset(const char *name);
133 extern const char *regs_query_register_name(unsigned int offset);
134 extern bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr);
135 extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
136 unsigned int n);
137
138 /**
139 * regs_get_register() - get register value from its offset
140 * @regs: pt_regs from which register value is gotten
141 * @offset: offset number of the register.
142 *
143 * regs_get_register returns the value of a register whose offset from @regs.
144 * The @offset is the offset of the register in struct pt_regs.
145 * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
146 */
regs_get_register(struct pt_regs * regs,unsigned int offset)147 static inline unsigned long regs_get_register(struct pt_regs *regs,
148 unsigned int offset)
149 {
150 if (unlikely(offset > MAX_REG_OFFSET))
151 return 0;
152 return *(unsigned long *)((unsigned long)regs + offset);
153 }
154
155 /* Valid only for Kernel mode traps. */
kernel_stack_pointer(struct pt_regs * regs)156 static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
157 {
158 return regs->ARM_sp;
159 }
160
user_stack_pointer(struct pt_regs * regs)161 static inline unsigned long user_stack_pointer(struct pt_regs *regs)
162 {
163 return regs->ARM_sp;
164 }
165
166 #define current_pt_regs(void) ({ (struct pt_regs *) \
167 ((current_stack_pointer | (THREAD_SIZE - 1)) - 7) - 1; \
168 })
169
170 #endif /* __ASSEMBLY__ */
171 #endif
172
