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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2/* Rewritten and vastly simplified by Rusty Russell for in-kernel
3 * module loader:
4 * Copyright 2002 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
5 */
6#ifndef _LINUX_KALLSYMS_H
7#define _LINUX_KALLSYMS_H
8
9#include <linux/errno.h>
10#include <linux/buildid.h>
11#include <linux/kernel.h>
12#include <linux/stddef.h>
13#include <linux/mm.h>
14#include <linux/module.h>
15
16#include <asm/sections.h>
17
18#define KSYM_NAME_LEN 128
19#define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s %s]") + \
20 (KSYM_NAME_LEN - 1) + \
21 2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + \
22 (BUILD_ID_SIZE_MAX * 2) + 1)
23
24struct cred;
25struct module;
26
27static inline int is_kernel_inittext(unsigned long addr)
28{
29 if (addr >= (unsigned long)_sinittext
30 && addr <= (unsigned long)_einittext)
31 return 1;
32 return 0;
33}
34
35static inline int is_kernel_text(unsigned long addr)
36{
37 if ((addr >= (unsigned long)_stext && addr <= (unsigned long)_etext) ||
38 arch_is_kernel_text(addr))
39 return 1;
40 return in_gate_area_no_mm(addr);
41}
42
43static inline int is_kernel(unsigned long addr)
44{
45 if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
46 return 1;
47 return in_gate_area_no_mm(addr);
48}
49
50static inline int is_ksym_addr(unsigned long addr)
51{
52 if (IS_ENABLED(CONFIG_KALLSYMS_ALL))
53 return is_kernel(addr);
54
55 return is_kernel_text(addr) || is_kernel_inittext(addr);
56}
57
58static inline void *dereference_symbol_descriptor(void *ptr)
59{
60#ifdef HAVE_DEREFERENCE_FUNCTION_DESCRIPTOR
61 struct module *mod;
62
63 ptr = dereference_kernel_function_descriptor(ptr);
64 if (is_ksym_addr((unsigned long)ptr))
65 return ptr;
66
67 preempt_disable();
68 mod = __module_address((unsigned long)ptr);
69 preempt_enable();
70
71 if (mod)
72 ptr = dereference_module_function_descriptor(mod, ptr);
73#endif
74 return ptr;
75}
76
77int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
78 unsigned long),
79 void *data);
80
81#ifdef CONFIG_KALLSYMS
82/* Lookup the address for a symbol. Returns 0 if not found. */
83unsigned long kallsyms_lookup_name(const char *name);
84
85extern int kallsyms_lookup_size_offset(unsigned long addr,
86 unsigned long *symbolsize,
87 unsigned long *offset);
88
89/* Lookup an address. modname is set to NULL if it's in the kernel. */
90const char *kallsyms_lookup(unsigned long addr,
91 unsigned long *symbolsize,
92 unsigned long *offset,
93 char **modname, char *namebuf);
94
95/* Look up a kernel symbol and return it in a text buffer. */
96extern int sprint_symbol(char *buffer, unsigned long address);
97extern int sprint_symbol_build_id(char *buffer, unsigned long address);
98extern int sprint_symbol_no_offset(char *buffer, unsigned long address);
99extern int sprint_backtrace(char *buffer, unsigned long address);
100extern int sprint_backtrace_build_id(char *buffer, unsigned long address);
101
102int lookup_symbol_name(unsigned long addr, char *symname);
103int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
104
105/* How and when do we show kallsyms values? */
106extern bool kallsyms_show_value(const struct cred *cred);
107
108#else /* !CONFIG_KALLSYMS */
109
110static inline unsigned long kallsyms_lookup_name(const char *name)
111{
112 return 0;
113}
114
115static inline int kallsyms_lookup_size_offset(unsigned long addr,
116 unsigned long *symbolsize,
117 unsigned long *offset)
118{
119 return 0;
120}
121
122static inline const char *kallsyms_lookup(unsigned long addr,
123 unsigned long *symbolsize,
124 unsigned long *offset,
125 char **modname, char *namebuf)
126{
127 return NULL;
128}
129
130static inline int sprint_symbol(char *buffer, unsigned long addr)
131{
132 *buffer = '\0';
133 return 0;
134}
135
136static inline int sprint_symbol_build_id(char *buffer, unsigned long address)
137{
138 *buffer = '\0';
139 return 0;
140}
141
142static inline int sprint_symbol_no_offset(char *buffer, unsigned long addr)
143{
144 *buffer = '\0';
145 return 0;
146}
147
148static inline int sprint_backtrace(char *buffer, unsigned long addr)
149{
150 *buffer = '\0';
151 return 0;
152}
153
154static inline int sprint_backtrace_build_id(char *buffer, unsigned long addr)
155{
156 *buffer = '\0';
157 return 0;
158}
159
160static inline int lookup_symbol_name(unsigned long addr, char *symname)
161{
162 return -ERANGE;
163}
164
165static inline int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
166{
167 return -ERANGE;
168}
169
170static inline bool kallsyms_show_value(const struct cred *cred)
171{
172 return false;
173}
174
175#endif /*CONFIG_KALLSYMS*/
176
177static inline void print_ip_sym(const char *loglvl, unsigned long ip)
178{
179 printk("%s[<%px>] %pS\n", loglvl, (void *) ip, (void *) ip);
180}
181
182#endif /*_LINUX_KALLSYMS_H*/