include/linux/kallsyms.h

   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
  13 #define KSYM_NAME_LEN 128
  14 #define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s]") + (KSYM_NAME_LEN - 1) + \
  15                          2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + 1)
  16
  17 struct module;
  18
  19 #ifdef CONFIG_KALLSYMS
  20 /* Lookup the address for a symbol. Returns 0 if not found. */
  21 unsigned long kallsyms_lookup_name(const char *name);
  22
  23 /* Call a function on each kallsyms symbol in the core kernel */
  24 int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
  25                                       unsigned long),
  26                             void *data);
  27
  28 extern int kallsyms_lookup_size_offset(unsigned long addr,
  29                                   unsigned long *symbolsize,
  30                                   unsigned long *offset);
  31
  32 /* Lookup an address.  modname is set to NULL if it's in the kernel. */
  33 const char *kallsyms_lookup(unsigned long addr,
  34                             unsigned long *symbolsize,
  35                             unsigned long *offset,
  36                             char **modname, char *namebuf);
  37
  38 /* Look up a kernel symbol and return it in a text buffer. */
  39 extern int sprint_symbol(char *buffer, unsigned long address);
  40 extern int sprint_symbol_no_offset(char *buffer, unsigned long address);
  41 extern int sprint_backtrace(char *buffer, unsigned long address);
  42
  43 /* Look up a kernel symbol and print it to the kernel messages. */
  44 extern void __print_symbol(const char *fmt, unsigned long address);
  45
  46 int lookup_symbol_name(unsigned long addr, char *symname);
  47 int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name);
  48
  49 #else /* !CONFIG_KALLSYMS */
  50
  51 static inline unsigned long kallsyms_lookup_name(const char *name)
  52 {
  53         return 0;
  54 }
  55
  56 static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *,
  57                                                     struct module *,
  58                                                     unsigned long),
  59                                           void *data)
  60 {
  61         return 0;
  62 }
  63
  64 static inline int kallsyms_lookup_size_offset(unsigned long addr,
  65                                               unsigned long *symbolsize,
  66                                               unsigned long *offset)
  67 {
  68         return 0;
  69 }
  70
  71 static inline const char *kallsyms_lookup(unsigned long addr,
  72                                           unsigned long *symbolsize,
  73                                           unsigned long *offset,
  74                                           char **modname, char *namebuf)
  75 {
  76         return NULL;
  77 }
  78
  79 static inline int sprint_symbol(char *buffer, unsigned long addr)
  80 {
  81         *buffer = '\0';
  82         return 0;
  83 }
  84
  85 static inline int sprint_symbol_no_offset(char *buffer, unsigned long addr)
  86 {
  87         *buffer = '\0';
  88         return 0;
  89 }
  90
  91 static inline int sprint_backtrace(char *buffer, unsigned long addr)
  92 {
  93         *buffer = '\0';
  94         return 0;
  95 }
  96
  97 static inline int lookup_symbol_name(unsigned long addr, char *symname)
  98 {
  99         return -ERANGE;
 100 }
 101
 102 static inline int lookup_symbol_attrs(unsigned long addr, unsigned long *size, unsigned long *offset, char *modname, char *name)
 103 {
 104         return -ERANGE;
 105 }
 106
 107 /* Stupid that this does nothing, but I didn't create this mess. */
 108 #define __print_symbol(fmt, addr)
 109 #endif /*CONFIG_KALLSYMS*/
 110
 111 /* This macro allows us to keep printk typechecking */
 112 static __printf(1, 2)
 113 void __check_printsym_format(const char *fmt, ...)
 114 {
 115 }
 116
 117 static inline void print_symbol(const char *fmt, unsigned long addr)
 118 {
 119         __check_printsym_format(fmt, "");
 120         __print_symbol(fmt, (unsigned long)
 121                        __builtin_extract_return_addr((void *)addr));
 122 }
 123
 124 static inline void print_ip_sym(unsigned long ip)
 125 {
 126         printk("[<%p>] %pS\n", (void *) ip, (void *) ip);
 127 }
 128
 129 #endif /*_LINUX_KALLSYMS_H*/