xref: /linux/include/linux/uprobes.h (revision 564eb714f5f09ac733c26860d5f0831f213fbdf1)
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 struct notifier_block;
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 
44 enum uprobe_filter_ctx {
45 	UPROBE_FILTER_REGISTER,
46 	UPROBE_FILTER_UNREGISTER,
47 	UPROBE_FILTER_MMAP,
48 };
49 
50 struct 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
63 enum 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  */
73 struct 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 /*
86  * On a breakpoint hit, thread contests for a slot.  It frees the
87  * slot after singlestep. Currently a fixed number of slots are
88  * allocated.
89  */
90 struct xol_area {
91 	wait_queue_head_t 	wq;		/* if all slots are busy */
92 	atomic_t 		slot_count;	/* number of in-use slots */
93 	unsigned long 		*bitmap;	/* 0 = free slot */
94 	struct page 		*page;
95 
96 	/*
97 	 * We keep the vma's vm_start rather than a pointer to the vma
98 	 * itself.  The probed process or a naughty kernel module could make
99 	 * the vma go away, and we must handle that reasonably gracefully.
100 	 */
101 	unsigned long 		vaddr;		/* Page(s) of instruction slots */
102 };
103 
104 struct uprobes_state {
105 	struct xol_area		*xol_area;
106 };
107 
108 extern int __weak set_swbp(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
109 extern int __weak set_orig_insn(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
110 extern bool __weak is_swbp_insn(uprobe_opcode_t *insn);
111 extern bool __weak is_trap_insn(uprobe_opcode_t *insn);
112 extern int uprobe_write_opcode(struct mm_struct *mm, unsigned long vaddr, uprobe_opcode_t);
113 extern int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
114 extern int uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool);
115 extern void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
116 extern int uprobe_mmap(struct vm_area_struct *vma);
117 extern void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end);
118 extern void uprobe_start_dup_mmap(void);
119 extern void uprobe_end_dup_mmap(void);
120 extern void uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm);
121 extern void uprobe_free_utask(struct task_struct *t);
122 extern void uprobe_copy_process(struct task_struct *t, unsigned long flags);
123 extern unsigned long __weak uprobe_get_swbp_addr(struct pt_regs *regs);
124 extern int uprobe_post_sstep_notifier(struct pt_regs *regs);
125 extern int uprobe_pre_sstep_notifier(struct pt_regs *regs);
126 extern void uprobe_notify_resume(struct pt_regs *regs);
127 extern bool uprobe_deny_signal(void);
128 extern bool arch_uprobe_skip_sstep(struct arch_uprobe *aup, struct pt_regs *regs);
129 extern void uprobe_clear_state(struct mm_struct *mm);
130 extern int  arch_uprobe_analyze_insn(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long addr);
131 extern int  arch_uprobe_pre_xol(struct arch_uprobe *aup, struct pt_regs *regs);
132 extern int  arch_uprobe_post_xol(struct arch_uprobe *aup, struct pt_regs *regs);
133 extern bool arch_uprobe_xol_was_trapped(struct task_struct *tsk);
134 extern int  arch_uprobe_exception_notify(struct notifier_block *self, unsigned long val, void *data);
135 extern void arch_uprobe_abort_xol(struct arch_uprobe *aup, struct pt_regs *regs);
136 extern unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs);
137 #else /* !CONFIG_UPROBES */
138 struct uprobes_state {
139 };
140 static inline int
141 uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
142 {
143 	return -ENOSYS;
144 }
145 static inline int
146 uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool add)
147 {
148 	return -ENOSYS;
149 }
150 static inline void
151 uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
152 {
153 }
154 static inline int uprobe_mmap(struct vm_area_struct *vma)
155 {
156 	return 0;
157 }
158 static inline void
159 uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end)
160 {
161 }
162 static inline void uprobe_start_dup_mmap(void)
163 {
164 }
165 static inline void uprobe_end_dup_mmap(void)
166 {
167 }
168 static inline void
169 uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm)
170 {
171 }
172 static inline void uprobe_notify_resume(struct pt_regs *regs)
173 {
174 }
175 static inline bool uprobe_deny_signal(void)
176 {
177 	return false;
178 }
179 static inline unsigned long uprobe_get_swbp_addr(struct pt_regs *regs)
180 {
181 	return 0;
182 }
183 static inline void uprobe_free_utask(struct task_struct *t)
184 {
185 }
186 static inline void uprobe_copy_process(struct task_struct *t, unsigned long flags)
187 {
188 }
189 static inline void uprobe_clear_state(struct mm_struct *mm)
190 {
191 }
192 #endif /* !CONFIG_UPROBES */
193 #endif	/* _LINUX_UPROBES_H */
194