xref: /linux-6.15/include/linux/kallsyms.h (revision 643d1f7f)
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/stddef.h>
10 
11 #define KSYM_NAME_LEN 128
12 #define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s]") + (KSYM_NAME_LEN - 1) + \
13 			 2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + 1)
14 
15 #ifdef CONFIG_KALLSYMS
16 /* Lookup the address for a symbol. Returns 0 if not found. */
17 unsigned long kallsyms_lookup_name(const char *name);
18 
19 extern int kallsyms_lookup_size_offset(unsigned long addr,
20 				  unsigned long *symbolsize,
21 				  unsigned long *offset);
22 
23 /* Lookup an address.  modname is set to NULL if it's in the kernel. */
24 const char *kallsyms_lookup(unsigned long addr,
25 			    unsigned long *symbolsize,
26 			    unsigned long *offset,
27 			    char **modname, char *namebuf);
28 
29 /* Look up a kernel symbol and return it in a text buffer. */
30 extern int sprint_symbol(char *buffer, unsigned long address);
31 
32 /* Look up a kernel symbol and print it to the kernel messages. */
33 extern void __print_symbol(const char *fmt, unsigned long address);
34 
35 int lookup_symbol_name(unsigned long addr, char *symname);
36 int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
37 
38 #else /* !CONFIG_KALLSYMS */
39 
40 static inline unsigned long kallsyms_lookup_name(const char *name)
41 {
42 	return 0;
43 }
44 
45 static inline int kallsyms_lookup_size_offset(unsigned long addr,
46 					      unsigned long *symbolsize,
47 					      unsigned long *offset)
48 {
49 	return 0;
50 }
51 
52 static inline const char *kallsyms_lookup(unsigned long addr,
53 					  unsigned long *symbolsize,
54 					  unsigned long *offset,
55 					  char **modname, char *namebuf)
56 {
57 	return NULL;
58 }
59 
60 static inline int sprint_symbol(char *buffer, unsigned long addr)
61 {
62 	*buffer = '\0';
63 	return 0;
64 }
65 
66 static inline int lookup_symbol_name(unsigned long addr, char *symname)
67 {
68 	return -ERANGE;
69 }
70 
71 static inline int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
72 {
73 	return -ERANGE;
74 }
75 
76 /* Stupid that this does nothing, but I didn't create this mess. */
77 #define __print_symbol(fmt, addr)
78 #endif /*CONFIG_KALLSYMS*/
79 
80 /* This macro allows us to keep printk typechecking */
81 static void __check_printsym_format(const char *fmt, ...)
82 __attribute__((format(printf,1,2)));
83 static inline void __check_printsym_format(const char *fmt, ...)
84 {
85 }
86 /* ia64 and ppc64 use function descriptors, which contain the real address */
87 #if defined(CONFIG_IA64) || defined(CONFIG_PPC64)
88 #define print_fn_descriptor_symbol(fmt, addr)		\
89 do {						\
90 	unsigned long *__faddr = (unsigned long*) addr;		\
91 	print_symbol(fmt, __faddr[0]);		\
92 } while (0)
93 #else
94 #define print_fn_descriptor_symbol(fmt, addr) print_symbol(fmt, addr)
95 #endif
96 
97 static inline void print_symbol(const char *fmt, unsigned long addr)
98 {
99 	__check_printsym_format(fmt, "");
100 	__print_symbol(fmt, (unsigned long)
101 		       __builtin_extract_return_addr((void *)addr));
102 }
103 
104 #ifndef CONFIG_64BIT
105 #define print_ip_sym(ip)		\
106 do {					\
107 	printk("[<%08lx>]", ip);	\
108 	print_symbol(" %s\n", ip);	\
109 } while(0)
110 #else
111 #define print_ip_sym(ip)		\
112 do {					\
113 	printk("[<%016lx>]", ip);	\
114 	print_symbol(" %s\n", ip);	\
115 } while(0)
116 #endif
117 
118 #endif /*_LINUX_KALLSYMS_H*/
119