1/* SPDX-License-Identifier: GPL-2.0-or-later */
2#ifndef _LINUX_UPROBES_H
3#define _LINUX_UPROBES_H
4/*
5 * User-space Probes (UProbes)
6 *
7 * Copyright (C) IBM Corporation, 2008-2012
8 * Authors:
9 *	Srikar Dronamraju
10 *	Jim Keniston
11 * Copyright (C) 2011-2012 Red Hat, Inc., Peter Zijlstra
12 */
13
14#include <linux/errno.h>
15#include <linux/rbtree.h>
16#include <linux/types.h>
17#include <linux/wait.h>
18
19struct vm_area_struct;
20struct mm_struct;
21struct inode;
22struct notifier_block;
23struct page;
24
25#define UPROBE_HANDLER_REMOVE		1
26#define UPROBE_HANDLER_MASK		1
27
28#define MAX_URETPROBE_DEPTH		64
29
30enum uprobe_filter_ctx {
31	UPROBE_FILTER_REGISTER,
32	UPROBE_FILTER_UNREGISTER,
33	UPROBE_FILTER_MMAP,
34};
35
36struct uprobe_consumer {
37	int (*handler)(struct uprobe_consumer *self, struct pt_regs *regs);
38	int (*ret_handler)(struct uprobe_consumer *self,
39				unsigned long func,
40				struct pt_regs *regs);
41	bool (*filter)(struct uprobe_consumer *self,
42				enum uprobe_filter_ctx ctx,
43				struct mm_struct *mm);
44
45	struct uprobe_consumer *next;
46};
47
48#ifdef CONFIG_UPROBES
49#include <asm/uprobes.h>
50
51enum uprobe_task_state {
52	UTASK_RUNNING,
53	UTASK_SSTEP,
54	UTASK_SSTEP_ACK,
55	UTASK_SSTEP_TRAPPED,
56};
57
58/*
59 * uprobe_task: Metadata of a task while it singlesteps.
60 */
61struct uprobe_task {
62	enum uprobe_task_state		state;
63
64	union {
65		struct {
66			struct arch_uprobe_task	autask;
67			unsigned long		vaddr;
68		};
69
70		struct {
71			struct callback_head	dup_xol_work;
72			unsigned long		dup_xol_addr;
73		};
74	};
75
76	struct uprobe			*active_uprobe;
77	unsigned long			xol_vaddr;
78
79	struct return_instance		*return_instances;
80	unsigned int			depth;
81};
82
83struct return_instance {
84	struct uprobe		*uprobe;
85	unsigned long		func;
86	unsigned long		stack;		/* stack pointer */
87	unsigned long		orig_ret_vaddr; /* original return address */
88	bool			chained;	/* true, if instance is nested */
89
90	struct return_instance	*next;		/* keep as stack */
91};
92
93enum rp_check {
94	RP_CHECK_CALL,
95	RP_CHECK_CHAIN_CALL,
96	RP_CHECK_RET,
97};
98
99struct xol_area;
100
101struct uprobes_state {
102	struct xol_area		*xol_area;
103};
104
105extern void __init uprobes_init(void);
106extern int set_swbp(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
107extern int set_orig_insn(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long vaddr);
108extern bool is_swbp_insn(uprobe_opcode_t *insn);
109extern bool is_trap_insn(uprobe_opcode_t *insn);
110extern unsigned long uprobe_get_swbp_addr(struct pt_regs *regs);
111extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs);
112extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr, uprobe_opcode_t);
113extern int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
114extern int uprobe_register_refctr(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
115extern int uprobe_apply(struct inode *inode, loff_t offset, struct uprobe_consumer *uc, bool);
116extern void uprobe_unregister(struct inode *inode, loff_t offset, struct uprobe_consumer *uc);
117extern int uprobe_mmap(struct vm_area_struct *vma);
118extern void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end);
119extern void uprobe_start_dup_mmap(void);
120extern void uprobe_end_dup_mmap(void);
121extern void uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm);
122extern void uprobe_free_utask(struct task_struct *t);
123extern void uprobe_copy_process(struct task_struct *t, unsigned long flags);
124extern int uprobe_post_sstep_notifier(struct pt_regs *regs);
125extern int uprobe_pre_sstep_notifier(struct pt_regs *regs);
126extern void uprobe_notify_resume(struct pt_regs *regs);
127extern bool uprobe_deny_signal(void);
128extern bool arch_uprobe_skip_sstep(struct arch_uprobe *aup, struct pt_regs *regs);
129extern void uprobe_clear_state(struct mm_struct *mm);
130extern int  arch_uprobe_analyze_insn(struct arch_uprobe *aup, struct mm_struct *mm, unsigned long addr);
131extern int  arch_uprobe_pre_xol(struct arch_uprobe *aup, struct pt_regs *regs);
132extern int  arch_uprobe_post_xol(struct arch_uprobe *aup, struct pt_regs *regs);
133extern bool arch_uprobe_xol_was_trapped(struct task_struct *tsk);
134extern int  arch_uprobe_exception_notify(struct notifier_block *self, unsigned long val, void *data);
135extern void arch_uprobe_abort_xol(struct arch_uprobe *aup, struct pt_regs *regs);
136extern unsigned long arch_uretprobe_hijack_return_addr(unsigned long trampoline_vaddr, struct pt_regs *regs);
137extern bool arch_uretprobe_is_alive(struct return_instance *ret, enum rp_check ctx, struct pt_regs *regs);
138extern bool arch_uprobe_ignore(struct arch_uprobe *aup, struct pt_regs *regs);
139extern void arch_uprobe_copy_ixol(struct page *page, unsigned long vaddr,
140					 void *src, unsigned long len);
141#else /* !CONFIG_UPROBES */
142struct uprobes_state {
143};
144
145static inline void uprobes_init(void)
146{
147}
148
149#define uprobe_get_trap_addr(regs)	instruction_pointer(regs)
150
151static inline int
152uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *uc)
153{
154	return -ENOSYS;
155}
156static inline int uprobe_register_refctr(struct inode *inode, loff_t offset, loff_t ref_ctr_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 void uprobe_free_utask(struct task_struct *t)
195{
196}
197static inline void uprobe_copy_process(struct task_struct *t, unsigned long flags)
198{
199}
200static inline void uprobe_clear_state(struct mm_struct *mm)
201{
202}
203#endif /* !CONFIG_UPROBES */
204#endif	/* _LINUX_UPROBES_H */
205