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#include <linux/rh_kabi.h>
  30
  31struct vm_area_struct;
  32struct mm_struct;
  33struct inode;
  34
  35#ifdef CONFIG_ARCH_SUPPORTS_UPROBES
  36# include <asm/uprobes.h>
  37#endif
  38
  39#define UPROBE_HANDLER_REMOVE           1
  40#define UPROBE_HANDLER_MASK             1
  41
  42#define MAX_URETPROBE_DEPTH             64
  43
  44enum uprobe_filter_ctx {
  45        UPROBE_FILTER_REGISTER,
  46        UPROBE_FILTER_UNREGISTER,
  47        UPROBE_FILTER_MMAP,
  48};
  49
  50struct uprobe_consumer {
  51        int (*handler)(struct uprobe_consumer *self, struct pt_regs *regs);
  52        int (*ret_handler)(struct uprobe_consumer *self,
  53                                unsigned long func,
  54                                struct pt_regs *regs);
  55        bool (*filter)(struct uprobe_consumer *self,
  56                                enum uprobe_filter_ctx ctx,
  57                                struct mm_struct *mm);
  58
  59        struct uprobe_consumer *next;
  60};
  61
  62#ifdef CONFIG_UPROBES
  63enum uprobe_task_state {
  64        UTASK_RUNNING,
  65        UTASK_SSTEP,
  66        UTASK_SSTEP_ACK,
  67        UTASK_SSTEP_TRAPPED,
  68};
  69
  70/*
  71 * uprobe_task: Metadata of a task while it singlesteps.
  72 */
  73struct uprobe_task {
  74        enum uprobe_task_state          state;
  75        struct arch_uprobe_task         autask;
  76
  77        struct return_instance          *return_instances;
  78        unsigned int                    depth;
  79        struct uprobe                   *active_uprobe;
  80
  81        unsigned long                   xol_vaddr;
  82        unsigned long                   vaddr;
  83};
  84
  85#ifndef __GENKSYMS__
  86struct return_instance {
  87        struct uprobe           *uprobe;
  88        unsigned long           func;
  89        unsigned long           stack;          /* stack pointer */
  90        unsigned long           orig_ret_vaddr; /* original return address */
  91        bool                    chained;        /* true, if instance is nested */
  92
  93        struct return_instance  *next;          /* keep as stack */
  94};
  95#endif
  96
  97enum rp_check {
  98        RP_CHECK_CALL,
  99        RP_CHECK_CHAIN_CALL,
 100        RP_CHECK_RET,
 101};
 102
 103/*
 104 * On a breakpoint hit, thread contests for a slot.  It frees the
 105 * slot after singlestep. Currently a fixed number of slots are
 106 * allocated.
 107 */
 108struct xol_area {
 109        wait_queue_head_t       wq;             /* if all slots are busy */
 110        atomic_t                slot_count;     /* number of in-use slots */
 111        unsigned long           *bitmap;        /* 0 = free slot */
 112        struct page             *page;
 113
 114        /*
 115         * We keep the vma's vm_start rather than a pointer to the vma
 116         * itself.  The probed process or a naughty kernel module could make
 117         * the vma go away, and we must handle that reasonably gracefully.
 118         */
 119        unsigned long           vaddr;          /* Page(s) of instruction slots */
 120};
 121
 122struct uprobes_state {
 123#ifdef CONFIG_S390
 124        RH_KABI_EXTEND(struct xol_area *xol_area)
 125#else
 126        struct xol_area *xol_area;
 127#endif
 128};
 129
 130extern int __weak set_swbp(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
 131extern int __weak set_orig_insn(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
 132extern bool __weak is_swbp_insn(uprobe_opcode_t *insn);
 133extern bool __weak is_trap_insn(uprobe_opcode_t *insn);
 134extern int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
 135extern int uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool);
 136extern void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
 137extern int uprobe_mmap(struct vm_area_struct *vma);
 138extern void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end);
 139extern void uprobe_start_dup_mmap(void);
 140extern void uprobe_end_dup_mmap(void);
 141extern void uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm);
 142extern void uprobe_free_utask(struct task_struct *t);
 143extern void uprobe_copy_process(struct task_struct *t, unsigned long flags);
 144extern unsigned long __weak uprobe_get_swbp_addr(struct pt_regs *regs);
 145extern int uprobe_post_sstep_notifier(struct pt_regs *regs);
 146extern int uprobe_pre_sstep_notifier(struct pt_regs *regs);
 147extern void uprobe_notify_resume(struct pt_regs *regs);
 148extern bool uprobe_deny_signal(void);
 149extern bool __weak arch_uprobe_skip_sstep(struct arch_uprobe *aup, struct pt_regs *regs);
 150extern bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx, struct pt_regs *regs);
 151extern void uprobe_clear_state(struct mm_struct *mm);
 152#else /* !CONFIG_UPROBES */
 153struct uprobes_state {
 154};
 155static inline int
 156uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
 157{
 158        return -ENOSYS;
 159}
 160static inline int
 161uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool add)
 162{
 163        return -ENOSYS;
 164}
 165static inline void
 166uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
 167{
 168}
 169static inline int uprobe_mmap(struct vm_area_struct *vma)
 170{
 171        return 0;
 172}
 173static inline void
 174uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end)
 175{
 176}
 177static inline void uprobe_start_dup_mmap(void)
 178{
 179}
 180static inline void uprobe_end_dup_mmap(void)
 181{
 182}
 183static inline void
 184uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm)
 185{
 186}
 187static inline void uprobe_notify_resume(struct pt_regs *regs)
 188{
 189}
 190static inline bool uprobe_deny_signal(void)
 191{
 192        return false;
 193}
 194static inline unsigned long uprobe_get_swbp_addr(struct pt_regs *regs)
 195{
 196        return 0;
 197}
 198static inline void uprobe_free_utask(struct task_struct *t)
 199{
 200}
 201static inline void uprobe_copy_process(struct task_struct *t, unsigned long flags)
 202{
 203}
 204static inline void uprobe_clear_state(struct mm_struct *mm)
 205{
 206}
 207#endif /* !CONFIG_UPROBES */
 208#endif  /* _LINUX_UPROBES_H */
 209