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_SMP 88 extern unsigned long profile_pc(struct pt_regs *regs); 89 #else 90 #define profile_pc(regs) instruction_pointer(regs) 91 #endif 92 93 #define predicate(x) ((x) & 0xf0000000) 94 #define PREDICATE_ALWAYS 0xe0000000 95 96 /* 97 * True if instr is a 32-bit thumb instruction. This works if instr 98 * is the first or only half-word of a thumb instruction. It also works 99 * when instr holds all 32-bits of a wide thumb instruction if stored 100 * in the form (first_half<<16)|(second_half) 101 */ 102 #define is_wide_instruction(instr) ((unsigned)(instr) >= 0xe800) 103 104 /* 105 * kprobe-based event tracer support 106 */ 107 #include <linux/stddef.h> 108 #include <linux/types.h> 109 #define MAX_REG_OFFSET (offsetof(struct pt_regs, ARM_ORIG_r0)) 110 111 extern int regs_query_register_offset(const char *name); 112 extern const char *regs_query_register_name(unsigned int offset); 113 extern bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr); 114 extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, 115 unsigned int n); 116 117 /** 118 * regs_get_register() - get register value from its offset 119 * @regs: pt_regs from which register value is gotten 120 * @offset: offset number of the register. 121 * 122 * regs_get_register returns the value of a register whose offset from @regs. 123 * The @offset is the offset of the register in struct pt_regs. 124 * If @offset is bigger than MAX_REG_OFFSET, this returns 0. 125 */ 126 static inline unsigned long regs_get_register(struct pt_regs *regs, 127 unsigned int offset) 128 { 129 if (unlikely(offset > MAX_REG_OFFSET)) 130 return 0; 131 return *(unsigned long *)((unsigned long)regs + offset); 132 } 133 134 /* Valid only for Kernel mode traps. */ 135 static inline unsigned long kernel_stack_pointer(struct pt_regs *regs) 136 { 137 return regs->ARM_sp; 138 } 139 140 static inline unsigned long user_stack_pointer(struct pt_regs *regs) 141 { 142 return regs->ARM_sp; 143 } 144 145 #define current_pt_regs(void) ({ \ 146 register unsigned long sp asm ("sp"); \ 147 (struct pt_regs *)((sp | (THREAD_SIZE - 1)) - 7) - 1; \ 148 }) 149 150 #endif /* __ASSEMBLY__ */ 151 #endif 152