Line data Source code
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 512
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 :
24 : struct cred;
25 : struct module;
26 :
27 : static inline int is_kernel_text(unsigned long addr)
28 : {
29 826 : if (__is_kernel_text(addr))
30 : return 1;
31 500 : return in_gate_area_no_mm(addr);
32 : }
33 :
34 : static inline int is_kernel(unsigned long addr)
35 : {
36 : if (__is_kernel(addr))
37 : return 1;
38 : return in_gate_area_no_mm(addr);
39 : }
40 :
41 : static inline int is_ksym_addr(unsigned long addr)
42 : {
43 : if (IS_ENABLED(CONFIG_KALLSYMS_ALL))
44 : return is_kernel(addr);
45 :
46 252 : return is_kernel_text(addr) || is_kernel_inittext(addr);
47 : }
48 :
49 : static inline void *dereference_symbol_descriptor(void *ptr)
50 : {
51 : #ifdef CONFIG_HAVE_FUNCTION_DESCRIPTORS
52 : struct module *mod;
53 :
54 : ptr = dereference_kernel_function_descriptor(ptr);
55 : if (is_ksym_addr((unsigned long)ptr))
56 : return ptr;
57 :
58 : preempt_disable();
59 : mod = __module_address((unsigned long)ptr);
60 : preempt_enable();
61 :
62 : if (mod)
63 : ptr = dereference_module_function_descriptor(mod, ptr);
64 : #endif
65 : return ptr;
66 : }
67 :
68 : #ifdef CONFIG_KALLSYMS
69 : unsigned long kallsyms_sym_address(int idx);
70 : int kallsyms_on_each_symbol(int (*fn)(void *, const char *, unsigned long),
71 : void *data);
72 : int kallsyms_on_each_match_symbol(int (*fn)(void *, unsigned long),
73 : const char *name, void *data);
74 :
75 : /* Lookup the address for a symbol. Returns 0 if not found. */
76 : unsigned long kallsyms_lookup_name(const char *name);
77 :
78 : extern int kallsyms_lookup_size_offset(unsigned long addr,
79 : unsigned long *symbolsize,
80 : unsigned long *offset);
81 :
82 : /* Lookup an address. modname is set to NULL if it's in the kernel. */
83 : const char *kallsyms_lookup(unsigned long addr,
84 : unsigned long *symbolsize,
85 : unsigned long *offset,
86 : char **modname, char *namebuf);
87 :
88 : /* Look up a kernel symbol and return it in a text buffer. */
89 : extern int sprint_symbol(char *buffer, unsigned long address);
90 : extern int sprint_symbol_build_id(char *buffer, unsigned long address);
91 : extern int sprint_symbol_no_offset(char *buffer, unsigned long address);
92 : extern int sprint_backtrace(char *buffer, unsigned long address);
93 : extern int sprint_backtrace_build_id(char *buffer, unsigned long address);
94 :
95 : int lookup_symbol_name(unsigned long addr, char *symname);
96 : int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
97 :
98 : /* How and when do we show kallsyms values? */
99 : extern bool kallsyms_show_value(const struct cred *cred);
100 :
101 : #else /* !CONFIG_KALLSYMS */
102 :
103 : static inline unsigned long kallsyms_lookup_name(const char *name)
104 : {
105 : return 0;
106 : }
107 :
108 : static inline int kallsyms_lookup_size_offset(unsigned long addr,
109 : unsigned long *symbolsize,
110 : unsigned long *offset)
111 : {
112 : return 0;
113 : }
114 :
115 : static inline const char *kallsyms_lookup(unsigned long addr,
116 : unsigned long *symbolsize,
117 : unsigned long *offset,
118 : char **modname, char *namebuf)
119 : {
120 : return NULL;
121 : }
122 :
123 : static inline int sprint_symbol(char *buffer, unsigned long addr)
124 : {
125 : *buffer = '\0';
126 : return 0;
127 : }
128 :
129 : static inline int sprint_symbol_build_id(char *buffer, unsigned long address)
130 : {
131 : *buffer = '\0';
132 : return 0;
133 : }
134 :
135 : static inline int sprint_symbol_no_offset(char *buffer, unsigned long addr)
136 : {
137 : *buffer = '\0';
138 : return 0;
139 : }
140 :
141 : static inline int sprint_backtrace(char *buffer, unsigned long addr)
142 : {
143 : *buffer = '\0';
144 : return 0;
145 : }
146 :
147 : static inline int sprint_backtrace_build_id(char *buffer, unsigned long addr)
148 : {
149 : *buffer = '\0';
150 : return 0;
151 : }
152 :
153 : static inline int lookup_symbol_name(unsigned long addr, char *symname)
154 : {
155 : return -ERANGE;
156 : }
157 :
158 : static inline int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
159 : {
160 : return -ERANGE;
161 : }
162 :
163 : static inline bool kallsyms_show_value(const struct cred *cred)
164 : {
165 : return false;
166 : }
167 :
168 : static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *, unsigned long),
169 : void *data)
170 : {
171 : return -EOPNOTSUPP;
172 : }
173 :
174 : static inline int kallsyms_on_each_match_symbol(int (*fn)(void *, unsigned long),
175 : const char *name, void *data)
176 : {
177 : return -EOPNOTSUPP;
178 : }
179 : #endif /*CONFIG_KALLSYMS*/
180 :
181 : static inline void print_ip_sym(const char *loglvl, unsigned long ip)
182 : {
183 : printk("%s[<%px>] %pS\n", loglvl, (void *) ip, (void *) ip);
184 : }
185 :
186 : #endif /*_LINUX_KALLSYMS_H*/
|
