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