LXR linux/include/linux/uprobes.h

   1#ifndef _LINUX_UPROBES_H
   2#define _LINUX_UPROBES_H
   3/*
   4 * User-space Probes (UProbes)
   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, 2008-2012
  21 * Authors:
  22 *      Srikar Dronamraju
  23 *      Jim Keniston
  24 * Copyright (C) 2011-2012 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
  25 */
  26
  27#include <linux/errno.h>
  28#include <linux/rbtree.h>
  29
  30struct vm_area_struct;
  31struct mm_struct;
  32struct inode;
  33
  34#ifdef CONFIG_ARCH_SUPPORTS_UPROBES
  35# include <asm/uprobes.h>
  36#endif
  37
  38/* flags that denote/change uprobes behaviour */
  39
  40/* Have a copy of original instruction */
  41#define UPROBE_COPY_INSN        0x1
  42
  43/* Dont run handlers when first register/ last unregister in progress*/
  44#define UPROBE_RUN_HANDLER      0x2
  45/* Can skip singlestep */
  46#define UPROBE_SKIP_SSTEP       0x4
  47
  48struct uprobe_consumer {
  49        int (*handler)(struct uprobe_consumer *self, struct pt_regs *regs);
  50        /*
  51         * filter is optional; If a filter exists, handler is run
  52         * if and only if filter returns true.
  53         */
  54        bool (*filter)(struct uprobe_consumer *self, struct task_struct *task);
  55
  56        struct uprobe_consumer *next;
  57};
  58
  59#ifdef CONFIG_UPROBES
  60enum uprobe_task_state {
  61        UTASK_RUNNING,
  62        UTASK_BP_HIT,
  63        UTASK_SSTEP,
  64        UTASK_SSTEP_ACK,
  65        UTASK_SSTEP_TRAPPED,
  66};
  67
  68/*
  69 * uprobe_task: Metadata of a task while it singlesteps.
  70 */
  71struct uprobe_task {
  72        enum uprobe_task_state          state;
  73        struct arch_uprobe_task         autask;
  74
  75        struct uprobe                   *active_uprobe;
  76
  77        unsigned long                   xol_vaddr;
  78        unsigned long                   vaddr;
  79};
  80
  81/*
  82 * On a breakpoint hit, thread contests for a slot.  It frees the
  83 * slot after singlestep. Currently a fixed number of slots are
  84 * allocated.
  85 */
  86struct xol_area {
  87        wait_queue_head_t       wq;             /* if all slots are busy */
  88        atomic_t                slot_count;     /* number of in-use slots */
  89        unsigned long           *bitmap;        /* 0 = free slot */
  90        struct page             *page;
  91
  92        /*
  93         * We keep the vma's vm_start rather than a pointer to the vma
  94         * itself.  The probed process or a naughty kernel module could make
  95         * the vma go away, and we must handle that reasonably gracefully.
  96         */
  97        unsigned long           vaddr;          /* Page(s) of instruction slots */
  98};
  99
 100struct uprobes_state {
 101        struct xol_area         *xol_area;
 102        atomic_t                count;
 103};
 104extern int __weak set_swbp(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
 105extern int __weak set_orig_insn(struct arch_uprobe *aup, struct mm_struct *mm,  unsigned long vaddr, bool verify);
 106extern bool __weak is_swbp_insn(uprobe_opcode_t *insn);
 107extern int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
 108extern void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
 109extern int uprobe_mmap(struct vm_area_struct *vma);
 110extern void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end);
 111extern void uprobe_free_utask(struct task_struct *t);
 112extern void uprobe_copy_process(struct task_struct *t);
 113extern unsigned long __weak uprobe_get_swbp_addr(struct pt_regs *regs);
 114extern int uprobe_post_sstep_notifier(struct pt_regs *regs);
 115extern int uprobe_pre_sstep_notifier(struct pt_regs *regs);
 116extern void uprobe_notify_resume(struct pt_regs *regs);
 117extern bool uprobe_deny_signal(void);
 118extern bool __weak arch_uprobe_skip_sstep(struct arch_uprobe *aup, struct pt_regs *regs);
 119extern void uprobe_clear_state(struct mm_struct *mm);
 120extern void uprobe_reset_state(struct mm_struct *mm);
 121#else /* !CONFIG_UPROBES */
 122struct uprobes_state {
 123};
 124static inline int
 125uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
 126{
 127        return -ENOSYS;
 128}
 129static inline void
 130uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
 131{
 132}
 133static inline int uprobe_mmap(struct vm_area_struct *vma)
 134{
 135        return 0;
 136}
 137static inline void
 138uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end)
 139{
 140}
 141static inline void uprobe_notify_resume(struct pt_regs *regs)
 142{
 143}
 144static inline bool uprobe_deny_signal(void)
 145{
 146        return false;
 147}
 148static inline unsigned long uprobe_get_swbp_addr(struct pt_regs *regs)
 149{
 150        return 0;
 151}
 152static inline void uprobe_free_utask(struct task_struct *t)
 153{
 154}
 155static inline void uprobe_copy_process(struct task_struct *t)
 156{
 157}
 158static inline void uprobe_clear_state(struct mm_struct *mm)
 159{
 160}
 161static inline void uprobe_reset_state(struct mm_struct *mm)
 162{
 163}
 164#endif /* !CONFIG_UPROBES */
 165#endif  /* _LINUX_UPROBES_H */
 166