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 /* 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
  48 struct 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
  60 enum 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  */
  71 struct 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  */
  86 struct 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
 100 struct uprobes_state {
 101         struct xol_area         *xol_area;
 102         atomic_t                count;
 103 };
 104 extern int __weak set_swbp(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
 105 extern int __weak set_orig_insn(struct arch_uprobe *aup, struct mm_struct *mm,  unsigned long vaddr, bool verify);
 106 extern bool __weak is_swbp_insn(uprobe_opcode_t *insn);
 107 extern int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
 108 extern void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
 109 extern int uprobe_mmap(struct vm_area_struct *vma);
 110 extern void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end);
 111 extern void uprobe_free_utask(struct task_struct *t);
 112 extern void uprobe_copy_process(struct task_struct *t);
 113 extern unsigned long __weak uprobe_get_swbp_addr(struct pt_regs *regs);
 114 extern int uprobe_post_sstep_notifier(struct pt_regs *regs);
 115 extern int uprobe_pre_sstep_notifier(struct pt_regs *regs);
 116 extern void uprobe_notify_resume(struct pt_regs *regs);
 117 extern bool uprobe_deny_signal(void);
 118 extern bool __weak arch_uprobe_skip_sstep(struct arch_uprobe *aup, struct pt_regs *regs);
 119 extern void uprobe_clear_state(struct mm_struct *mm);
 120 extern void uprobe_reset_state(struct mm_struct *mm);
 121 #else /* !CONFIG_UPROBES */
 122 struct uprobes_state {
 123 };
 124 static inline int
 125 uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
 126 {
 127         return -ENOSYS;
 128 }
 129 static inline void
 130 uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
 131 {
 132 }
 133 static inline int uprobe_mmap(struct vm_area_struct *vma)
 134 {
 135         return 0;
 136 }
 137 static inline void
 138 uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end)
 139 {
 140 }
 141 static inline void uprobe_notify_resume(struct pt_regs *regs)
 142 {
 143 }
 144 static inline bool uprobe_deny_signal(void)
 145 {
 146         return false;
 147 }
 148 static inline unsigned long uprobe_get_swbp_addr(struct pt_regs *regs)
 149 {
 150         return 0;
 151 }
 152 static inline void uprobe_free_utask(struct task_struct *t)
 153 {
 154 }
 155 static inline void uprobe_copy_process(struct task_struct *t)
 156 {
 157 }
 158 static inline void uprobe_clear_state(struct mm_struct *mm)
 159 {
 160 }
 161 static inline void uprobe_reset_state(struct mm_struct *mm)
 162 {
 163 }
 164 #endif /* !CONFIG_UPROBES */
 165 #endif  /* _LINUX_UPROBES_H */