arch/arm/include/asm/ptrace.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  *  arch/arm/include/asm/ptrace.h
   4  *
   5  *  Copyright (C) 1996-2003 Russell King
   6  */
   7 #ifndef __ASM_ARM_PTRACE_H
   8 #define __ASM_ARM_PTRACE_H
   9
  10 #include <uapi/asm/ptrace.h>
  11
  12 #ifndef __ASSEMBLY__
  13 #include <linux/types.h>
  14
  15 struct pt_regs {
  16         unsigned long uregs[18];
  17 };
  18
  19 struct svc_pt_regs {
  20         struct pt_regs regs;
  21         u32 dacr;
  22         u32 addr_limit;
  23 };
  24
  25 #define to_svc_pt_regs(r) container_of(r, struct svc_pt_regs, regs)
  26
  27 #define user_mode(regs) \
  28         (((regs)->ARM_cpsr & 0xf) == 0)
  29
  30 #ifdef CONFIG_ARM_THUMB
  31 #define thumb_mode(regs) \
  32         (((regs)->ARM_cpsr & PSR_T_BIT))
  33 #else
  34 #define thumb_mode(regs) (0)
  35 #endif
  36
  37 #ifndef CONFIG_CPU_V7M
  38 #define isa_mode(regs) \
  39         ((((regs)->ARM_cpsr & PSR_J_BIT) >> (__ffs(PSR_J_BIT) - 1)) | \
  40          (((regs)->ARM_cpsr & PSR_T_BIT) >> (__ffs(PSR_T_BIT))))
  41 #else
  42 #define isa_mode(regs) 1 /* Thumb */
  43 #endif
  44
  45 #define processor_mode(regs) \
  46         ((regs)->ARM_cpsr & MODE_MASK)
  47
  48 #define interrupts_enabled(regs) \
  49         (!((regs)->ARM_cpsr & PSR_I_BIT))
  50
  51 #define fast_interrupts_enabled(regs) \
  52         (!((regs)->ARM_cpsr & PSR_F_BIT))
  53
  54 /* Are the current registers suitable for user mode?
  55  * (used to maintain security in signal handlers)
  56  */
  57 static inline int valid_user_regs(struct pt_regs *regs)
  58 {
  59 #ifndef CONFIG_CPU_V7M
  60         unsigned long mode = regs->ARM_cpsr & MODE_MASK;
  61
  62         /*
  63          * Always clear the F (FIQ) and A (delayed abort) bits
  64          */
  65         regs->ARM_cpsr &= ~(PSR_F_BIT | PSR_A_BIT);
  66
  67         if ((regs->ARM_cpsr & PSR_I_BIT) == 0) {
  68                 if (mode == USR_MODE)
  69                         return 1;
  70                 if (elf_hwcap & HWCAP_26BIT && mode == USR26_MODE)
  71                         return 1;
  72         }
  73
  74         /*
  75          * Force CPSR to something logical...
  76          */
  77         regs->ARM_cpsr &= PSR_f | PSR_s | PSR_x | PSR_T_BIT | MODE32_BIT;
  78         if (!(elf_hwcap & HWCAP_26BIT))
  79                 regs->ARM_cpsr |= USR_MODE;
  80
  81         return 0;
  82 #else /* ifndef CONFIG_CPU_V7M */
  83         return 1;
  84 #endif
  85 }
  86
  87 static inline long regs_return_value(struct pt_regs *regs)
  88 {
  89         return regs->ARM_r0;
  90 }
  91
  92 #define instruction_pointer(regs)       (regs)->ARM_pc
  93
  94 #ifdef CONFIG_THUMB2_KERNEL
  95 #define frame_pointer(regs) (regs)->ARM_r7
  96 #else
  97 #define frame_pointer(regs) (regs)->ARM_fp
  98 #endif
  99
 100 static inline void instruction_pointer_set(struct pt_regs *regs,
 101                                            unsigned long val)
 102 {
 103         instruction_pointer(regs) = val;
 104 }
 105
 106 #ifdef CONFIG_SMP
 107 extern unsigned long profile_pc(struct pt_regs *regs);
 108 #else
 109 #define profile_pc(regs) instruction_pointer(regs)
 110 #endif
 111
 112 #define predicate(x)            ((x) & 0xf0000000)
 113 #define PREDICATE_ALWAYS        0xe0000000
 114
 115 /*
 116  * True if instr is a 32-bit thumb instruction. This works if instr
 117  * is the first or only half-word of a thumb instruction. It also works
 118  * when instr holds all 32-bits of a wide thumb instruction if stored
 119  * in the form (first_half<<16)|(second_half)
 120  */
 121 #define is_wide_instruction(instr)      ((unsigned)(instr) >= 0xe800)
 122
 123 /*
 124  * kprobe-based event tracer support
 125  */
 126 #include <linux/compiler.h>
 127 #define MAX_REG_OFFSET (offsetof(struct pt_regs, ARM_ORIG_r0))
 128
 129 extern int regs_query_register_offset(const char *name);
 130 extern const char *regs_query_register_name(unsigned int offset);
 131 extern bool regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr);
 132 extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs,
 133                                                unsigned int n);
 134
 135 /**
 136  * regs_get_register() - get register value from its offset
 137  * @regs:          pt_regs from which register value is gotten
 138  * @offset:    offset number of the register.
 139  *
 140  * regs_get_register returns the value of a register whose offset from @regs.
 141  * The @offset is the offset of the register in struct pt_regs.
 142  * If @offset is bigger than MAX_REG_OFFSET, this returns 0.
 143  */
 144 static inline unsigned long regs_get_register(struct pt_regs *regs,
 145                                               unsigned int offset)
 146 {
 147         if (unlikely(offset > MAX_REG_OFFSET))
 148                 return 0;
 149         return *(unsigned long *)((unsigned long)regs + offset);
 150 }
 151
 152 /* Valid only for Kernel mode traps. */
 153 static inline unsigned long kernel_stack_pointer(struct pt_regs *regs)
 154 {
 155         return regs->ARM_sp;
 156 }
 157
 158 static inline unsigned long user_stack_pointer(struct pt_regs *regs)
 159 {
 160         return regs->ARM_sp;
 161 }
 162
 163 #define current_pt_regs(void) ({ (struct pt_regs *)                     \
 164                 ((current_stack_pointer | (THREAD_SIZE - 1)) - 7) - 1;  \
 165 })
 166
 167 #endif /* __ASSEMBLY__ */
 168 #endif