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