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 | if (__is_kernel_text(addr)) |
30 | return 1; |
31 | 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 | 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 | /* How and when do we show kallsyms values? */ |
69 | extern bool kallsyms_show_value(const struct cred *cred); |
70 | |
71 | #ifdef CONFIG_KALLSYMS |
72 | unsigned long kallsyms_sym_address(int idx); |
73 | int kallsyms_on_each_symbol(int (*fn)(void *, const char *, unsigned long), |
74 | void *data); |
75 | int kallsyms_on_each_match_symbol(int (*fn)(void *, unsigned long), |
76 | const char *name, void *data); |
77 | |
78 | /* Lookup the address for a symbol. Returns 0 if not found. */ |
79 | unsigned long kallsyms_lookup_name(const char *name); |
80 | |
81 | extern int kallsyms_lookup_size_offset(unsigned long addr, |
82 | unsigned long *symbolsize, |
83 | unsigned long *offset); |
84 | |
85 | /* Lookup an address. modname is set to NULL if it's in the kernel. */ |
86 | const char *kallsyms_lookup(unsigned long addr, |
87 | unsigned long *symbolsize, |
88 | unsigned long *offset, |
89 | char **modname, char *namebuf); |
90 | |
91 | /* Look up a kernel symbol and return it in a text buffer. */ |
92 | extern int sprint_symbol(char *buffer, unsigned long address); |
93 | extern int sprint_symbol_build_id(char *buffer, unsigned long address); |
94 | extern int sprint_symbol_no_offset(char *buffer, unsigned long address); |
95 | extern int sprint_backtrace(char *buffer, unsigned long address); |
96 | extern int sprint_backtrace_build_id(char *buffer, unsigned long address); |
97 | |
98 | int lookup_symbol_name(unsigned long addr, char *symname); |
99 | |
100 | #else /* !CONFIG_KALLSYMS */ |
101 | |
102 | static inline unsigned long kallsyms_lookup_name(const char *name) |
103 | { |
104 | return 0; |
105 | } |
106 | |
107 | static inline int kallsyms_lookup_size_offset(unsigned long addr, |
108 | unsigned long *symbolsize, |
109 | unsigned long *offset) |
110 | { |
111 | return 0; |
112 | } |
113 | |
114 | static inline const char *kallsyms_lookup(unsigned long addr, |
115 | unsigned long *symbolsize, |
116 | unsigned long *offset, |
117 | char **modname, char *namebuf) |
118 | { |
119 | return NULL; |
120 | } |
121 | |
122 | static inline int sprint_symbol(char *buffer, unsigned long addr) |
123 | { |
124 | *buffer = '\0'; |
125 | return 0; |
126 | } |
127 | |
128 | static inline int sprint_symbol_build_id(char *buffer, unsigned long address) |
129 | { |
130 | *buffer = '\0'; |
131 | return 0; |
132 | } |
133 | |
134 | static inline int sprint_symbol_no_offset(char *buffer, unsigned long addr) |
135 | { |
136 | *buffer = '\0'; |
137 | return 0; |
138 | } |
139 | |
140 | static inline int sprint_backtrace(char *buffer, unsigned long addr) |
141 | { |
142 | *buffer = '\0'; |
143 | return 0; |
144 | } |
145 | |
146 | static inline int sprint_backtrace_build_id(char *buffer, unsigned long addr) |
147 | { |
148 | *buffer = '\0'; |
149 | return 0; |
150 | } |
151 | |
152 | static inline int lookup_symbol_name(unsigned long addr, char *symname) |
153 | { |
154 | return -ERANGE; |
155 | } |
156 | |
157 | static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *, unsigned long), |
158 | void *data) |
159 | { |
160 | return -EOPNOTSUPP; |
161 | } |
162 | |
163 | static inline int kallsyms_on_each_match_symbol(int (*fn)(void *, unsigned long), |
164 | const char *name, void *data) |
165 | { |
166 | return -EOPNOTSUPP; |
167 | } |
168 | #endif /*CONFIG_KALLSYMS*/ |
169 | |
170 | static inline void print_ip_sym(const char *loglvl, unsigned long ip) |
171 | { |
172 | printk("%s[<%px>] %pS\n" , loglvl, (void *) ip, (void *) ip); |
173 | } |
174 | |
175 | #endif /*_LINUX_KALLSYMS_H*/ |
176 | |