include/asm-x86/kprobes.h

   1 #ifndef _ASM_KPROBES_H
   2 #define _ASM_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
  28 #define  __ARCH_WANT_KPROBES_INSN_SLOT
  29
  30 struct pt_regs;
  31 struct kprobe;
  32
  33 typedef u8 kprobe_opcode_t;
  34 #define BREAKPOINT_INSTRUCTION  0xcc
  35 #define RELATIVEJUMP_INSTRUCTION 0xe9
  36 #define MAX_INSN_SIZE 16
  37 #define MAX_STACK_SIZE 64
  38 #define MIN_STACK_SIZE(ADDR) (((MAX_STACK_SIZE) < \
  39         (((unsigned long)current_thread_info()) + THREAD_SIZE \
  40          - (unsigned long)(ADDR))) \
  41         ? (MAX_STACK_SIZE) \
  42         : (((unsigned long)current_thread_info()) + THREAD_SIZE \
  43            - (unsigned long)(ADDR)))
  44
  45 #define ARCH_SUPPORTS_KRETPROBES
  46 #define flush_insn_slot(p)      do { } while (0)
  47
  48 extern const int kretprobe_blacklist_size;
  49
  50 void arch_remove_kprobe(struct kprobe *p);
  51 void kretprobe_trampoline(void);
  52
  53 /* Architecture specific copy of original instruction*/
  54 struct arch_specific_insn {
  55         /* copy of the original instruction */
  56         kprobe_opcode_t *insn;
  57         /*
  58          * boostable = -1: This instruction type is not boostable.
  59          * boostable = 0: This instruction type is boostable.
  60          * boostable = 1: This instruction has been boosted: we have
  61          * added a relative jump after the instruction copy in insn,
  62          * so no single-step and fixup are needed (unless there's
  63          * a post_handler or break_handler).
  64          */
  65         int boostable;
  66 };
  67
  68 struct prev_kprobe {
  69         struct kprobe *kp;
  70         unsigned long status;
  71         unsigned long old_flags;
  72         unsigned long saved_flags;
  73 };
  74
  75 /* per-cpu kprobe control block */
  76 struct kprobe_ctlblk {
  77         unsigned long kprobe_status;
  78         unsigned long kprobe_old_flags;
  79         unsigned long kprobe_saved_flags;
  80         unsigned long *jprobe_saved_sp;
  81         struct pt_regs jprobe_saved_regs;
  82         kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
  83         struct prev_kprobe prev_kprobe;
  84 };
  85
  86 /* trap3/1 are intr gates for kprobes.  So, restore the status of IF,
  87  * if necessary, before executing the original int3/1 (trap) handler.
  88  */
  89 static inline void restore_interrupts(struct pt_regs *regs)
  90 {
  91         if (regs->flags & X86_EFLAGS_IF)
  92                 local_irq_enable();
  93 }
  94
  95 extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
  96 extern int kprobe_exceptions_notify(struct notifier_block *self,
  97                                     unsigned long val, void *data);
  98 #endif                          /* _ASM_KPROBES_H */