include/asm-x86/kprobes_32.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  * 2002-Oct     Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
  23  *              Probes initial implementation ( includes suggestions from
  24  *              Rusty Russell).
  25  * 2004-Oct     Prasanna S Panchamukhi <prasanna@in.ibm.com> and Jim Keniston
  26  *              kenistoj@us.ibm.com adopted from i386.
  27  */
  28 #include <linux/types.h>
  29 #include <linux/ptrace.h>
  30 #include <linux/percpu.h>
  31
  32 #define  __ARCH_WANT_KPROBES_INSN_SLOT
  33
  34 struct pt_regs;
  35 struct kprobe;
  36
  37 typedef u8 kprobe_opcode_t;
  38 #define BREAKPOINT_INSTRUCTION  0xcc
  39 #define RELATIVEJUMP_INSTRUCTION 0xe9
  40 #define MAX_INSN_SIZE 16
  41 #define MAX_STACK_SIZE 64
  42 #define MIN_STACK_SIZE(ADDR) (((MAX_STACK_SIZE) < \
  43         (((unsigned long)current_thread_info()) + THREAD_SIZE \
  44          - (unsigned long)(ADDR))) \
  45         ? (MAX_STACK_SIZE) \
  46         : (((unsigned long)current_thread_info()) + THREAD_SIZE \
  47            - (unsigned long)(ADDR)))
  48
  49 #define ARCH_SUPPORTS_KRETPROBES
  50 #define flush_insn_slot(p)      do { } while (0)
  51
  52 extern const int kretprobe_blacklist_size;
  53
  54 void arch_remove_kprobe(struct kprobe *p);
  55 void kretprobe_trampoline(void);
  56
  57 /* Architecture specific copy of original instruction*/
  58 struct arch_specific_insn {
  59         /* copy of the original instruction */
  60         kprobe_opcode_t *insn;
  61         /*
  62          * boostable = -1: This instruction type is not boostable.
  63          * boostable = 0: This instruction type is boostable.
  64          * boostable = 1: This instruction has been boosted: we have
  65          * added a relative jump after the instruction copy in insn,
  66          * so no single-step and fixup are needed (unless there's
  67          * a post_handler or break_handler).
  68          */
  69         int boostable;
  70 };
  71
  72 struct prev_kprobe {
  73         struct kprobe *kp;
  74         unsigned long status;
  75         unsigned long old_flags;
  76         unsigned long saved_flags;
  77 };
  78
  79 /* per-cpu kprobe control block */
  80 struct kprobe_ctlblk {
  81         unsigned long kprobe_status;
  82         unsigned long kprobe_old_flags;
  83         unsigned long kprobe_saved_flags;
  84         unsigned long *jprobe_saved_sp;
  85         struct pt_regs jprobe_saved_regs;
  86         kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
  87         struct prev_kprobe prev_kprobe;
  88 };
  89
  90 /* trap3/1 are intr gates for kprobes.  So, restore the status of IF,
  91  * if necessary, before executing the original int3/1 (trap) handler.
  92  */
  93 static inline void restore_interrupts(struct pt_regs *regs)
  94 {
  95         if (regs->flags & IF_MASK)
  96                 local_irq_enable();
  97 }
  98
  99 extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
 100 extern int kprobe_exceptions_notify(struct notifier_block *self,
 101                                     unsigned long val, void *data);
 102 #endif                          /* _ASM_KPROBES_H */