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 * $FreeBSD$ 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, 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 int ndeps; /* number of dependencies */ 83 linker_file_t* deps; /* list of dependencies */ 84 STAILQ_HEAD(, common_symbol) common; /* list of common symbols */ 85 TAILQ_HEAD(, module) modules; /* modules in this file */ 86 TAILQ_ENTRY(linker_file) loaded; /* preload dependency support */ 87 int loadcnt; /* load counter value */ 88 89 /* 90 * Function Boundary Tracing (FBT) or Statically Defined Tracing (SDT) 91 * fields. 92 */ 93 int nenabled; /* number of enabled probes. */ 94 int fbt_nentries; /* number of fbt entries created. */ 95 void *sdt_probes; 96 int sdt_nentries; 97 size_t sdt_nprobes; 98 size_t sdt_size; 99 }; 100 101 /* 102 * Object implementing a class of file (a.out, elf, etc.) 103 */ 104 typedef struct linker_class *linker_class_t; 105 typedef TAILQ_HEAD(, linker_class) linker_class_list_t; 106 107 struct linker_class { 108 KOBJ_CLASS_FIELDS; 109 TAILQ_ENTRY(linker_class) link; /* list of all file classes */ 110 }; 111 112 /* 113 * Function type used when iterating over the list of linker files. 114 */ 115 typedef int linker_predicate_t(linker_file_t, void *); 116 117 /* 118 * The "file" for the kernel. 119 */ 120 extern linker_file_t linker_kernel_file; 121 122 /* 123 * Obtain a reference to a module, loading it if required. 124 */ 125 int linker_reference_module(const char* _modname, struct mod_depend *_verinfo, 126 linker_file_t* _result); 127 128 /* 129 * Release a reference to a module, unloading it if there are no more 130 * references. Note that one should either provide a module name and 131 * optional version info or a linker file, but not both. 132 */ 133 int linker_release_module(const char *_modname, struct mod_depend *_verinfo, 134 linker_file_t _file); 135 136 /* 137 * Iterate over all of the currently loaded linker files calling the 138 * predicate function while the function returns 0. Returns the value 139 * returned by the last predicate function. 140 */ 141 int linker_file_foreach(linker_predicate_t *_predicate, void *_context); 142 143 /* 144 * Lookup a symbol in a file. If deps is TRUE, look in dependencies 145 * if not found in file. 146 */ 147 caddr_t linker_file_lookup_symbol(linker_file_t _file, const char* _name, 148 int _deps); 149 150 /* 151 * Lookup a linker set in a file. Return pointers to the first entry, 152 * last + 1, and count of entries. Use: for (p = start; p < stop; p++) {} 153 * void *start is really: "struct yoursetmember ***start;" 154 */ 155 int linker_file_lookup_set(linker_file_t _file, const char *_name, 156 void *_start, void *_stop, int *_count); 157 158 /* 159 * List all functions in a file. 160 */ 161 int linker_file_function_listall(linker_file_t, int (*)(linker_file_t, 162 linker_symval_t *, void *), void *); 163 164 /* 165 * Functions soley for use by the linker class handlers. 166 */ 167 int linker_add_class(linker_class_t _cls); 168 int linker_file_unload(linker_file_t _file, int flags); 169 int linker_load_dependencies(linker_file_t _lf); 170 linker_file_t linker_make_file(const char* _filename, linker_class_t _cls); 171 172 /* 173 * DDB Helpers, tuned specifically for ddb/db_kld.c 174 */ 175 int linker_ddb_lookup(const char *_symstr, c_linker_sym_t *_sym); 176 int linker_ddb_search_symbol(caddr_t _value, c_linker_sym_t *_sym, 177 long *_diffp); 178 int linker_ddb_symbol_values(c_linker_sym_t _sym, linker_symval_t *_symval); 179 int linker_ddb_search_symbol_name(caddr_t value, char *buf, u_int buflen, 180 long *offset); 181 182 /* 183 * stack(9) helper for situations where kernel locking is required. 184 */ 185 int linker_search_symbol_name(caddr_t value, char *buf, u_int buflen, 186 long *offset); 187 188 189 /* HWPMC helper */ 190 void *linker_hwpmc_list_objects(void); 191 192 #endif /* _KERNEL */ 193 194 /* 195 * Module information subtypes 196 */ 197 #define MODINFO_END 0x0000 /* End of list */ 198 #define MODINFO_NAME 0x0001 /* Name of module (string) */ 199 #define MODINFO_TYPE 0x0002 /* Type of module (string) */ 200 #define MODINFO_ADDR 0x0003 /* Loaded address */ 201 #define MODINFO_SIZE 0x0004 /* Size of module */ 202 #define MODINFO_EMPTY 0x0005 /* Has been deleted */ 203 #define MODINFO_ARGS 0x0006 /* Parameters string */ 204 #define MODINFO_METADATA 0x8000 /* Module-specfic */ 205 206 #define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */ 207 #define MODINFOMD_ELFHDR 0x0002 /* ELF header */ 208 #define MODINFOMD_SSYM 0x0003 /* start of symbols */ 209 #define MODINFOMD_ESYM 0x0004 /* end of symbols */ 210 #define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */ 211 /* These values are MD on these two platforms */ 212 #if !defined(__sparc64__) && !defined(__powerpc__) 213 #define MODINFOMD_ENVP 0x0006 /* envp[] */ 214 #define MODINFOMD_HOWTO 0x0007 /* boothowto */ 215 #define MODINFOMD_KERNEND 0x0008 /* kernend */ 216 #endif 217 #define MODINFOMD_SHDR 0x0009 /* section header table */ 218 #define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */ 219 220 #define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */ 221 222 #ifdef _KERNEL 223 #define MD_FETCH(mdp, info, type) ({ \ 224 type *__p; \ 225 __p = (type *)preload_search_info((mdp), MODINFO_METADATA | (info)); \ 226 __p ? *__p : 0; \ 227 }) 228 #endif 229 230 #define LINKER_HINTS_VERSION 1 /* linker.hints file version */ 231 232 #ifdef _KERNEL 233 234 /* 235 * Module lookup 236 */ 237 extern caddr_t preload_metadata; 238 extern caddr_t preload_search_by_name(const char *_name); 239 extern caddr_t preload_search_by_type(const char *_type); 240 extern caddr_t preload_search_next_name(caddr_t _base); 241 extern caddr_t preload_search_info(caddr_t _mod, int _inf); 242 extern void preload_delete_name(const char *_name); 243 extern void preload_bootstrap_relocate(vm_offset_t _offset); 244 245 #ifdef KLD_DEBUG 246 247 extern int kld_debug; 248 #define KLD_DEBUG_FILE 1 /* file load/unload */ 249 #define KLD_DEBUG_SYM 2 /* symbol lookup */ 250 251 #define KLD_DPF(cat, args) \ 252 do { \ 253 if (kld_debug & KLD_DEBUG_##cat) printf args; \ 254 } while (0) 255 256 #else 257 258 #define KLD_DPF(cat, args) 259 260 #endif 261 262 typedef Elf_Addr elf_lookup_fn(linker_file_t, Elf_Size, int); 263 264 /* Support functions */ 265 int elf_reloc(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu); 266 int elf_reloc_local(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu); 267 const Elf_Sym *elf_get_sym(linker_file_t _lf, Elf_Size _symidx); 268 const char *elf_get_symname(linker_file_t _lf, Elf_Size _symidx); 269 270 int elf_cpu_load_file(linker_file_t); 271 int elf_cpu_unload_file(linker_file_t); 272 273 /* values for type */ 274 #define ELF_RELOC_REL 1 275 #define ELF_RELOC_RELA 2 276 277 /* 278 * This is version 1 of the KLD file status structure. It is identified 279 * by its _size_ in the version field. 280 */ 281 struct kld_file_stat_1 { 282 int version; /* set to sizeof(struct kld_file_stat_1) */ 283 char name[MAXPATHLEN]; 284 int refs; 285 int id; 286 caddr_t address; /* load address */ 287 size_t size; /* size in bytes */ 288 }; 289 #endif /* _KERNEL */ 290 291 struct kld_file_stat { 292 int version; /* set to sizeof(struct kld_file_stat) */ 293 char name[MAXPATHLEN]; 294 int refs; 295 int id; 296 caddr_t address; /* load address */ 297 size_t size; /* size in bytes */ 298 char pathname[MAXPATHLEN]; 299 }; 300 301 struct kld_sym_lookup { 302 int version; /* set to sizeof(struct kld_sym_lookup) */ 303 char *symname; /* Symbol name we are looking up */ 304 u_long symvalue; 305 size_t symsize; 306 }; 307 #define KLDSYM_LOOKUP 1 308 309 /* 310 * Flags for kldunloadf() and linker_file_unload() 311 */ 312 #define LINKER_UNLOAD_NORMAL 0 313 #define LINKER_UNLOAD_FORCE 1 314 315 #ifndef _KERNEL 316 317 #include <sys/cdefs.h> 318 319 __BEGIN_DECLS 320 int kldload(const char* _file); 321 int kldunload(int _fileid); 322 int kldunloadf(int _fileid, int flags); 323 int kldfind(const char* _file); 324 int kldnext(int _fileid); 325 int kldstat(int _fileid, struct kld_file_stat* _stat); 326 int kldfirstmod(int _fileid); 327 int kldsym(int _fileid, int _cmd, void *_data); 328 __END_DECLS 329 330 #endif 331 332 #endif /* !_SYS_LINKER_H_ */ 333