FreeBSD/Linux Kernel Cross Reference
sys/sys/linker.h
1 /*-
2 * Copyright (c) 1997-2000 Doug Rabson
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: releng/11.2/sys/sys/linker.h 333720 2018-05-17 15:24:53Z kib $
27 */
28
29 #ifndef _SYS_LINKER_H_
30 #define _SYS_LINKER_H_
31
32 #ifdef _KERNEL
33
34 #include <machine/elf.h>
35 #include <sys/kobj.h>
36
37 #ifdef MALLOC_DECLARE
38 MALLOC_DECLARE(M_LINKER);
39 #endif
40
41 struct mod_depend;
42
43 /*
44 * Object representing a file which has been loaded by the linker.
45 */
46 typedef struct linker_file* linker_file_t;
47 typedef TAILQ_HEAD(, linker_file) linker_file_list_t;
48
49 typedef caddr_t linker_sym_t; /* opaque symbol */
50 typedef c_caddr_t c_linker_sym_t; /* const opaque symbol */
51 typedef int (*linker_function_name_callback_t)(const char *, void *);
52
53 /*
54 * expanded out linker_sym_t
55 */
56 typedef struct linker_symval {
57 const char* name;
58 caddr_t value;
59 size_t size;
60 } linker_symval_t;
61
62 typedef int (*linker_function_nameval_callback_t)(linker_file_t, int, linker_symval_t *, void *);
63
64 struct common_symbol {
65 STAILQ_ENTRY(common_symbol) link;
66 char* name;
67 caddr_t address;
68 };
69
70 struct linker_file {
71 KOBJ_FIELDS;
72 int refs; /* reference count */
73 int userrefs; /* kldload(2) count */
74 int flags;
75 #define LINKER_FILE_LINKED 0x1 /* file has been fully linked */
76 TAILQ_ENTRY(linker_file) link; /* list of all loaded files */
77 char* filename; /* file which was loaded */
78 char* pathname; /* file name with full path */
79 int id; /* unique id */
80 caddr_t address; /* load address */
81 size_t size; /* size of file */
82 caddr_t ctors_addr; /* address of .ctors */
83 size_t ctors_size; /* size of .ctors */
84 int ndeps; /* number of dependencies */
85 linker_file_t* deps; /* list of dependencies */
86 STAILQ_HEAD(, common_symbol) common; /* list of common symbols */
87 TAILQ_HEAD(, module) modules; /* modules in this file */
88 TAILQ_ENTRY(linker_file) loaded; /* preload dependency support */
89 int loadcnt; /* load counter value */
90
91 /*
92 * Function Boundary Tracing (FBT) or Statically Defined Tracing (SDT)
93 * fields.
94 */
95 int nenabled; /* number of enabled probes. */
96 int fbt_nentries; /* number of fbt entries created. */
97 };
98
99 /*
100 * Object implementing a class of file (a.out, elf, etc.)
101 */
102 typedef struct linker_class *linker_class_t;
103 typedef TAILQ_HEAD(, linker_class) linker_class_list_t;
104
105 struct linker_class {
106 KOBJ_CLASS_FIELDS;
107 TAILQ_ENTRY(linker_class) link; /* list of all file classes */
108 };
109
110 /*
111 * Function type used when iterating over the list of linker files.
112 */
113 typedef int linker_predicate_t(linker_file_t, void *);
114
115 /*
116 * The "file" for the kernel.
117 */
118 extern linker_file_t linker_kernel_file;
119
120 /*
121 * Obtain a reference to a module, loading it if required.
122 */
123 int linker_reference_module(const char* _modname, struct mod_depend *_verinfo,
124 linker_file_t* _result);
125
126 /*
127 * Release a reference to a module, unloading it if there are no more
128 * references. Note that one should either provide a module name and
129 * optional version info or a linker file, but not both.
130 */
131 int linker_release_module(const char *_modname, struct mod_depend *_verinfo,
132 linker_file_t _file);
133
134 /*
135 * Iterate over all of the currently loaded linker files calling the
136 * predicate function while the function returns 0. Returns the value
137 * returned by the last predicate function.
138 */
139 int linker_file_foreach(linker_predicate_t *_predicate, void *_context);
140
141 /*
142 * Lookup a symbol in a file. If deps is TRUE, look in dependencies
143 * if not found in file.
144 */
145 caddr_t linker_file_lookup_symbol(linker_file_t _file, const char* _name,
146 int _deps);
147
148 /*
149 * Lookup a linker set in a file. Return pointers to the first entry,
150 * last + 1, and count of entries. Use: for (p = start; p < stop; p++) {}
151 * void *start is really: "struct yoursetmember ***start;"
152 */
153 int linker_file_lookup_set(linker_file_t _file, const char *_name,
154 void *_start, void *_stop, int *_count);
155
156 /*
157 * List all functions in a file.
158 */
159 int linker_file_function_listall(linker_file_t,
160 linker_function_nameval_callback_t, void *);
161
162 /*
163 * Functions solely for use by the linker class handlers.
164 */
165 int linker_add_class(linker_class_t _cls);
166 int linker_file_unload(linker_file_t _file, int flags);
167 int linker_load_dependencies(linker_file_t _lf);
168 linker_file_t linker_make_file(const char* _filename, linker_class_t _cls);
169
170 /*
171 * DDB Helpers, tuned specifically for ddb/db_kld.c
172 */
173 int linker_ddb_lookup(const char *_symstr, c_linker_sym_t *_sym);
174 int linker_ddb_search_symbol(caddr_t _value, c_linker_sym_t *_sym,
175 long *_diffp);
176 int linker_ddb_symbol_values(c_linker_sym_t _sym, linker_symval_t *_symval);
177 int linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen,
178 long *offset);
179
180 /*
181 * stack(9) helper for situations where kernel locking is required.
182 */
183 int linker_search_symbol_name(caddr_t value, char *buf, u_int buflen,
184 long *offset);
185
186
187 /* HWPMC helper */
188 void *linker_hwpmc_list_objects(void);
189
190 #endif /* _KERNEL */
191
192 /*
193 * Module information subtypes
194 */
195 #define MODINFO_END 0x0000 /* End of list */
196 #define MODINFO_NAME 0x0001 /* Name of module (string) */
197 #define MODINFO_TYPE 0x0002 /* Type of module (string) */
198 #define MODINFO_ADDR 0x0003 /* Loaded address */
199 #define MODINFO_SIZE 0x0004 /* Size of module */
200 #define MODINFO_EMPTY 0x0005 /* Has been deleted */
201 #define MODINFO_ARGS 0x0006 /* Parameters string */
202 #define MODINFO_METADATA 0x8000 /* Module-specfic */
203
204 #define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */
205 #define MODINFOMD_ELFHDR 0x0002 /* ELF header */
206 #define MODINFOMD_SSYM 0x0003 /* start of symbols */
207 #define MODINFOMD_ESYM 0x0004 /* end of symbols */
208 #define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */
209 /* These values are MD on these two platforms */
210 #if !defined(__sparc64__) && !defined(__powerpc__)
211 #define MODINFOMD_ENVP 0x0006 /* envp[] */
212 #define MODINFOMD_HOWTO 0x0007 /* boothowto */
213 #define MODINFOMD_KERNEND 0x0008 /* kernend */
214 #endif
215 #define MODINFOMD_SHDR 0x0009 /* section header table */
216 #define MODINFOMD_CTORS_ADDR 0x000a /* address of .ctors */
217 #define MODINFOMD_CTORS_SIZE 0x000b /* size of .ctors */
218 #define MODINFOMD_FW_HANDLE 0x000c /* Firmware dependent handle */
219 #define MODINFOMD_KEYBUF 0x000d /* Crypto key intake buffer */
220 #define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */
221
222 #define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */
223
224 #ifdef _KERNEL
225 #define MD_FETCH(mdp, info, type) ({ \
226 type *__p; \
227 __p = (type *)preload_search_info((mdp), MODINFO_METADATA | (info)); \
228 __p ? *__p : 0; \
229 })
230 #endif
231
232 #define LINKER_HINTS_VERSION 1 /* linker.hints file version */
233 #define LINKER_HINTS_MAX (1 << 20) /* Allow at most 1MB for linker.hints */
234
235 #ifdef _KERNEL
236
237 /*
238 * Module lookup
239 */
240 extern vm_offset_t preload_addr_relocate;
241 extern caddr_t preload_metadata;
242
243 extern void * preload_fetch_addr(caddr_t _mod);
244 extern size_t preload_fetch_size(caddr_t _mod);
245 extern caddr_t preload_search_by_name(const char *_name);
246 extern caddr_t preload_search_by_type(const char *_type);
247 extern caddr_t preload_search_next_name(caddr_t _base);
248 extern caddr_t preload_search_info(caddr_t _mod, int _inf);
249 extern void preload_delete_name(const char *_name);
250 extern void preload_bootstrap_relocate(vm_offset_t _offset);
251
252 #ifdef KLD_DEBUG
253
254 extern int kld_debug;
255 #define KLD_DEBUG_FILE 1 /* file load/unload */
256 #define KLD_DEBUG_SYM 2 /* symbol lookup */
257
258 #define KLD_DPF(cat, args) \
259 do { \
260 if (kld_debug & KLD_DEBUG_##cat) printf args; \
261 } while (0)
262
263 #else
264
265 #define KLD_DPF(cat, args)
266
267 #endif
268
269 typedef int elf_lookup_fn(linker_file_t, Elf_Size, int, Elf_Addr *);
270
271 /* Support functions */
272 int elf_reloc(linker_file_t _lf, Elf_Addr base, const void *_rel,
273 int _type, elf_lookup_fn _lu);
274 int elf_reloc_ifunc(linker_file_t _lf, Elf_Addr base, const void *_rel,
275 int _type, elf_lookup_fn _lu);
276 int elf_reloc_local(linker_file_t _lf, Elf_Addr base, const void *_rel,
277 int _type, elf_lookup_fn _lu);
278 Elf_Addr elf_relocaddr(linker_file_t _lf, Elf_Addr addr);
279 const Elf_Sym *elf_get_sym(linker_file_t _lf, Elf_Size _symidx);
280 const char *elf_get_symname(linker_file_t _lf, Elf_Size _symidx);
281 void link_elf_ireloc(caddr_t kmdp);
282
283 typedef struct linker_ctf {
284 const uint8_t *ctftab; /* Decompressed CTF data. */
285 int ctfcnt; /* Number of CTF data bytes. */
286 const Elf_Sym *symtab; /* Ptr to the symbol table. */
287 int nsym; /* Number of symbols. */
288 const char *strtab; /* Ptr to the string table. */
289 int strcnt; /* Number of string bytes. */
290 uint32_t **ctfoffp; /* Ptr to array of obj/fnc offsets. */
291 uint32_t **typoffp; /* Ptr to array of type offsets. */
292 long *typlenp; /* Ptr to number of type data entries. */
293 } linker_ctf_t;
294
295 int linker_ctf_get(linker_file_t, linker_ctf_t *);
296
297 int elf_cpu_load_file(linker_file_t);
298 int elf_cpu_unload_file(linker_file_t);
299
300 /* values for type */
301 #define ELF_RELOC_REL 1
302 #define ELF_RELOC_RELA 2
303
304 /*
305 * This is version 1 of the KLD file status structure. It is identified
306 * by its _size_ in the version field.
307 */
308 struct kld_file_stat_1 {
309 int version; /* set to sizeof(struct kld_file_stat_1) */
310 char name[MAXPATHLEN];
311 int refs;
312 int id;
313 caddr_t address; /* load address */
314 size_t size; /* size in bytes */
315 };
316 #endif /* _KERNEL */
317
318 struct kld_file_stat {
319 int version; /* set to sizeof(struct kld_file_stat) */
320 char name[MAXPATHLEN];
321 int refs;
322 int id;
323 caddr_t address; /* load address */
324 size_t size; /* size in bytes */
325 char pathname[MAXPATHLEN];
326 };
327
328 struct kld_sym_lookup {
329 int version; /* set to sizeof(struct kld_sym_lookup) */
330 char *symname; /* Symbol name we are looking up */
331 u_long symvalue;
332 size_t symsize;
333 };
334 #define KLDSYM_LOOKUP 1
335
336 /*
337 * Flags for kldunloadf() and linker_file_unload()
338 */
339 #define LINKER_UNLOAD_NORMAL 0
340 #define LINKER_UNLOAD_FORCE 1
341
342 #ifndef _KERNEL
343
344 #include <sys/cdefs.h>
345
346 __BEGIN_DECLS
347 int kldload(const char* _file);
348 int kldunload(int _fileid);
349 int kldunloadf(int _fileid, int flags);
350 int kldfind(const char* _file);
351 int kldnext(int _fileid);
352 int kldstat(int _fileid, struct kld_file_stat* _stat);
353 int kldfirstmod(int _fileid);
354 int kldsym(int _fileid, int _cmd, void *_data);
355 __END_DECLS
356
357 #endif
358
359 #endif /* !_SYS_LINKER_H_ */
Cache object: a3313e9ed06255295811c7cd69925823
|