xref: /linux-6.15/include/linux/kallsyms.h (revision db4e8395)
1 /* Rewritten and vastly simplified by Rusty Russell for in-kernel
2  * module loader:
3  *   Copyright 2002 Rusty Russell <[email protected]> IBM Corporation
4  */
5 #ifndef _LINUX_KALLSYMS_H
6 #define _LINUX_KALLSYMS_H
7 
8 #include <linux/errno.h>
9 #include <linux/kernel.h>
10 #include <linux/stddef.h>
11 
12 #define KSYM_NAME_LEN 128
13 #define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s]") + (KSYM_NAME_LEN - 1) + \
14 			 2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + 1)
15 
16 struct module;
17 
18 #ifdef CONFIG_KALLSYMS
19 /* Lookup the address for a symbol. Returns 0 if not found. */
20 unsigned long kallsyms_lookup_name(const char *name);
21 
22 /* Call a function on each kallsyms symbol in the core kernel */
23 int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
24 				      unsigned long),
25 			    void *data);
26 
27 extern int kallsyms_lookup_size_offset(unsigned long addr,
28 				  unsigned long *symbolsize,
29 				  unsigned long *offset);
30 
31 /* Lookup an address.  modname is set to NULL if it's in the kernel. */
32 const char *kallsyms_lookup(unsigned long addr,
33 			    unsigned long *symbolsize,
34 			    unsigned long *offset,
35 			    char **modname, char *namebuf);
36 
37 /* Look up a kernel symbol and return it in a text buffer. */
38 extern int sprint_symbol(char *buffer, unsigned long address);
39 extern int sprint_backtrace(char *buffer, unsigned long address);
40 
41 /* Look up a kernel symbol and print it to the kernel messages. */
42 extern void __print_symbol(const char *fmt, unsigned long address);
43 
44 int lookup_symbol_name(unsigned long addr, char *symname);
45 int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
46 
47 #else /* !CONFIG_KALLSYMS */
48 
49 static inline unsigned long kallsyms_lookup_name(const char *name)
50 {
51 	return 0;
52 }
53 
54 static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *,
55 						    struct module *,
56 						    unsigned long),
57 					  void *data)
58 {
59 	return 0;
60 }
61 
62 static inline int kallsyms_lookup_size_offset(unsigned long addr,
63 					      unsigned long *symbolsize,
64 					      unsigned long *offset)
65 {
66 	return 0;
67 }
68 
69 static inline const char *kallsyms_lookup(unsigned long addr,
70 					  unsigned long *symbolsize,
71 					  unsigned long *offset,
72 					  char **modname, char *namebuf)
73 {
74 	return NULL;
75 }
76 
77 static inline int sprint_symbol(char *buffer, unsigned long addr)
78 {
79 	*buffer = '\0';
80 	return 0;
81 }
82 
83 static inline int sprint_backtrace(char *buffer, unsigned long addr)
84 {
85 	*buffer = '\0';
86 	return 0;
87 }
88 
89 static inline int lookup_symbol_name(unsigned long addr, char *symname)
90 {
91 	return -ERANGE;
92 }
93 
94 static inline int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
95 {
96 	return -ERANGE;
97 }
98 
99 /* Stupid that this does nothing, but I didn't create this mess. */
100 #define __print_symbol(fmt, addr)
101 #endif /*CONFIG_KALLSYMS*/
102 
103 /* This macro allows us to keep printk typechecking */
104 static void __check_printsym_format(const char *fmt, ...)
105 __attribute__((format(printf,1,2)));
106 static inline void __check_printsym_format(const char *fmt, ...)
107 {
108 }
109 
110 static inline void print_symbol(const char *fmt, unsigned long addr)
111 {
112 	__check_printsym_format(fmt, "");
113 	__print_symbol(fmt, (unsigned long)
114 		       __builtin_extract_return_addr((void *)addr));
115 }
116 
117 static inline void print_ip_sym(unsigned long ip)
118 {
119 	printk("[<%p>] %pS\n", (void *) ip, (void *) ip);
120 }
121 
122 #endif /*_LINUX_KALLSYMS_H*/
123