arch/x86/include/asm/kprobes.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 #ifndef _ASM_X86_KPROBES_H
   3 #define _ASM_X86_KPROBES_H
   4 /*
   5  *  Kernel Probes (KProbes)
   6  *
   7  * Copyright (C) IBM Corporation, 2002, 2004
   8  *
   9  * See arch/x86/kernel/kprobes.c for x86 kprobes history.
  10  */
  11
  12 #include <asm-generic/kprobes.h>
  13
  14 #define BREAKPOINT_INSTRUCTION  0xcc
  15
  16 #ifdef CONFIG_KPROBES
  17 #include <linux/types.h>
  18 #include <linux/ptrace.h>
  19 #include <linux/percpu.h>
  20 #include <asm/insn.h>
  21
  22 #define  __ARCH_WANT_KPROBES_INSN_SLOT
  23
  24 struct pt_regs;
  25 struct kprobe;
  26
  27 typedef u8 kprobe_opcode_t;
  28 #define RELATIVEJUMP_OPCODE 0xe9
  29 #define RELATIVEJUMP_SIZE 5
  30 #define RELATIVECALL_OPCODE 0xe8
  31 #define RELATIVE_ADDR_SIZE 4
  32 #define MAX_STACK_SIZE 64
  33 #define CUR_STACK_SIZE(ADDR) \
  34         (current_top_of_stack() - (unsigned long)(ADDR))
  35 #define MIN_STACK_SIZE(ADDR)                            \
  36         (MAX_STACK_SIZE < CUR_STACK_SIZE(ADDR) ?        \
  37          MAX_STACK_SIZE : CUR_STACK_SIZE(ADDR))
  38
  39 #define flush_insn_slot(p)      do { } while (0)
  40
  41 /* optinsn template addresses */
  42 extern __visible kprobe_opcode_t optprobe_template_entry[];
  43 extern __visible kprobe_opcode_t optprobe_template_val[];
  44 extern __visible kprobe_opcode_t optprobe_template_call[];
  45 extern __visible kprobe_opcode_t optprobe_template_end[];
  46 #define MAX_OPTIMIZED_LENGTH (MAX_INSN_SIZE + RELATIVE_ADDR_SIZE)
  47 #define MAX_OPTINSN_SIZE                                \
  48         (((unsigned long)optprobe_template_end -        \
  49           (unsigned long)optprobe_template_entry) +     \
  50          MAX_OPTIMIZED_LENGTH + RELATIVEJUMP_SIZE)
  51
  52 extern const int kretprobe_blacklist_size;
  53
  54 void arch_remove_kprobe(struct kprobe *p);
  55 asmlinkage void kretprobe_trampoline(void);
  56
  57 extern void arch_kprobe_override_function(struct pt_regs *regs);
  58
  59 /* Architecture specific copy of original instruction*/
  60 struct arch_specific_insn {
  61         /* copy of the original instruction */
  62         kprobe_opcode_t *insn;
  63         /*
  64          * boostable = false: This instruction type is not boostable.
  65          * boostable = true: This instruction has been boosted: we have
  66          * added a relative jump after the instruction copy in insn,
  67          * so no single-step and fixup are needed (unless there's
  68          * a post_handler).
  69          */
  70         bool boostable;
  71         bool if_modifier;
  72 };
  73
  74 struct arch_optimized_insn {
  75         /* copy of the original instructions */
  76         kprobe_opcode_t copied_insn[RELATIVE_ADDR_SIZE];
  77         /* detour code buffer */
  78         kprobe_opcode_t *insn;
  79         /* the size of instructions copied to detour code buffer */
  80         size_t size;
  81 };
  82
  83 /* Return true (!0) if optinsn is prepared for optimization. */
  84 static inline int arch_prepared_optinsn(struct arch_optimized_insn *optinsn)
  85 {
  86         return optinsn->size;
  87 }
  88
  89 struct prev_kprobe {
  90         struct kprobe *kp;
  91         unsigned long status;
  92         unsigned long old_flags;
  93         unsigned long saved_flags;
  94 };
  95
  96 /* per-cpu kprobe control block */
  97 struct kprobe_ctlblk {
  98         unsigned long kprobe_status;
  99         unsigned long kprobe_old_flags;
 100         unsigned long kprobe_saved_flags;
 101         struct prev_kprobe prev_kprobe;
 102 };
 103
 104 extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
 105 extern int kprobe_exceptions_notify(struct notifier_block *self,
 106                                     unsigned long val, void *data);
 107 extern int kprobe_int3_handler(struct pt_regs *regs);
 108 extern int kprobe_debug_handler(struct pt_regs *regs);
 109
 110 #endif /* CONFIG_KPROBES */
 111 #endif /* _ASM_X86_KPROBES_H */