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