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