LXR linux/arch/x86/include/asm/kprobes.h

   1#ifndef _ASM_X86_KPROBES_H
   2#define _ASM_X86_KPROBES_H
   3/*
   4 *  Kernel Probes (KProbes)
   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 as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19 *
  20 * Copyright (C) IBM Corporation, 2002, 2004
  21 *
  22 * See arch/x86/kernel/kprobes.c for x86 kprobes history.
  23 */
  24#include <linux/types.h>
  25#include <linux/ptrace.h>
  26#include <linux/percpu.h>
  27#include <asm/insn.h>
  28
  29#define  __ARCH_WANT_KPROBES_INSN_SLOT
  30
  31struct pt_regs;
  32struct kprobe;
  33
  34typedef u8 kprobe_opcode_t;
  35#define BREAKPOINT_INSTRUCTION  0xcc
  36#define RELATIVEJUMP_OPCODE 0xe9
  37#define RELATIVEJUMP_SIZE 5
  38#define RELATIVECALL_OPCODE 0xe8
  39#define RELATIVE_ADDR_SIZE 4
  40#define MAX_STACK_SIZE 64
  41#define MIN_STACK_SIZE(ADDR)                                           \
  42        (((MAX_STACK_SIZE) < (((unsigned long)current_thread_info()) + \
  43                              THREAD_SIZE - (unsigned long)(ADDR)))    \
  44         ? (MAX_STACK_SIZE)                                            \
  45         : (((unsigned long)current_thread_info()) +                   \
  46            THREAD_SIZE - (unsigned long)(ADDR)))
  47
  48#define flush_insn_slot(p)      do { } while (0)
  49
  50/* optinsn template addresses */
  51extern __visible kprobe_opcode_t optprobe_template_entry;
  52extern __visible kprobe_opcode_t optprobe_template_val;
  53extern __visible kprobe_opcode_t optprobe_template_call;
  54extern __visible kprobe_opcode_t optprobe_template_end;
  55#define MAX_OPTIMIZED_LENGTH (MAX_INSN_SIZE + RELATIVE_ADDR_SIZE)
  56#define MAX_OPTINSN_SIZE                                \
  57        (((unsigned long)&optprobe_template_end -       \
  58          (unsigned long)&optprobe_template_entry) +    \
  59         MAX_OPTIMIZED_LENGTH + RELATIVEJUMP_SIZE)
  60
  61extern const int kretprobe_blacklist_size;
  62
  63void arch_remove_kprobe(struct kprobe *p);
  64asmlinkage void kretprobe_trampoline(void);
  65
  66/* Architecture specific copy of original instruction*/
  67struct arch_specific_insn {
  68        /* copy of the original instruction */
  69        kprobe_opcode_t *insn;
  70        /*
  71         * boostable = -1: This instruction type is not boostable.
  72         * boostable = 0: This instruction type is boostable.
  73         * boostable = 1: This instruction has been boosted: we have
  74         * added a relative jump after the instruction copy in insn,
  75         * so no single-step and fixup are needed (unless there's
  76         * a post_handler or break_handler).
  77         */
  78        int boostable;
  79        bool if_modifier;
  80};
  81
  82struct arch_optimized_insn {
  83        /* copy of the original instructions */
  84        kprobe_opcode_t copied_insn[RELATIVE_ADDR_SIZE];
  85        /* detour code buffer */
  86        kprobe_opcode_t *insn;
  87        /* the size of instructions copied to detour code buffer */
  88        size_t size;
  89};
  90
  91/* Return true (!0) if optinsn is prepared for optimization. */
  92static inline int arch_prepared_optinsn(struct arch_optimized_insn *optinsn)
  93{
  94        return optinsn->size;
  95}
  96
  97struct prev_kprobe {
  98        struct kprobe *kp;
  99        unsigned long status;
 100        unsigned long old_flags;
 101        unsigned long saved_flags;
 102};
 103
 104/* per-cpu kprobe control block */
 105struct kprobe_ctlblk {
 106        unsigned long kprobe_status;
 107        unsigned long kprobe_old_flags;
 108        unsigned long kprobe_saved_flags;
 109        unsigned long *jprobe_saved_sp;
 110        struct pt_regs jprobe_saved_regs;
 111        kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
 112        struct prev_kprobe prev_kprobe;
 113};
 114
 115extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
 116extern int kprobe_exceptions_notify(struct notifier_block *self,
 117                                    unsigned long val, void *data);
 118extern int kprobe_int3_handler(struct pt_regs *regs);
 119extern int kprobe_debug_handler(struct pt_regs *regs);
 120#endif /* _ASM_X86_KPROBES_H */
 121