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 struct common_symbol { 63 STAILQ_ENTRY(common_symbol) link; 64 char* name; 65 caddr_t address; 66 }; 67 68 struct linker_file { 69 KOBJ_FIELDS; 70 int refs; /* reference count */ 71 int userrefs; /* kldload(2) count */ 72 int flags; 73 #define LINKER_FILE_LINKED 0x1 /* file has been fully linked */ 74 TAILQ_ENTRY(linker_file) link; /* list of all loaded files */ 75 char* filename; /* file which was loaded */ 76 char* pathname; /* file name with full path */ 77 int id; /* unique id */ 78 caddr_t address; /* load address */ 79 size_t size; /* size of file */ 80 int ndeps; /* number of dependencies */ 81 linker_file_t* deps; /* list of dependencies */ 82 STAILQ_HEAD(, common_symbol) common; /* list of common symbols */ 83 TAILQ_HEAD(, module) modules; /* modules in this file */ 84 TAILQ_ENTRY(linker_file) loaded; /* preload dependency support */ 85 int loadcnt; /* load counter value */ 86 87 /* 88 * Function Boundary Tracing (FBT) or Statically Defined Tracing (SDT) 89 * fields. 90 */ 91 int nenabled; /* number of enabled probes. */ 92 int fbt_nentries; /* number of fbt entries created. */ 93 void *sdt_probes; 94 int sdt_nentries; 95 size_t sdt_nprobes; 96 size_t sdt_size; 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 * Functions soley for use by the linker class handlers. 158 */ 159 int linker_add_class(linker_class_t _cls); 160 int linker_file_unload(linker_file_t _file, int flags); 161 int linker_load_dependencies(linker_file_t _lf); 162 linker_file_t linker_make_file(const char* _filename, linker_class_t _cls); 163 164 /* 165 * DDB Helpers, tuned specifically for ddb/db_kld.c 166 */ 167 int linker_ddb_lookup(const char *_symstr, c_linker_sym_t *_sym); 168 int linker_ddb_search_symbol(caddr_t _value, c_linker_sym_t *_sym, 169 long *_diffp); 170 int linker_ddb_symbol_values(c_linker_sym_t _sym, linker_symval_t *_symval); 171 172 173 /* HWPMC helper */ 174 void *linker_hwpmc_list_objects(void); 175 176 #endif /* _KERNEL */ 177 178 /* 179 * Module information subtypes 180 */ 181 #define MODINFO_END 0x0000 /* End of list */ 182 #define MODINFO_NAME 0x0001 /* Name of module (string) */ 183 #define MODINFO_TYPE 0x0002 /* Type of module (string) */ 184 #define MODINFO_ADDR 0x0003 /* Loaded address */ 185 #define MODINFO_SIZE 0x0004 /* Size of module */ 186 #define MODINFO_EMPTY 0x0005 /* Has been deleted */ 187 #define MODINFO_ARGS 0x0006 /* Parameters string */ 188 #define MODINFO_METADATA 0x8000 /* Module-specfic */ 189 190 #define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */ 191 #define MODINFOMD_ELFHDR 0x0002 /* ELF header */ 192 #define MODINFOMD_SSYM 0x0003 /* start of symbols */ 193 #define MODINFOMD_ESYM 0x0004 /* end of symbols */ 194 #define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */ 195 /* These values are MD on these two platforms */ 196 #if !defined(__sparc64__) && !defined(__powerpc__) 197 #define MODINFOMD_ENVP 0x0006 /* envp[] */ 198 #define MODINFOMD_HOWTO 0x0007 /* boothowto */ 199 #define MODINFOMD_KERNEND 0x0008 /* kernend */ 200 #endif 201 #define MODINFOMD_SHDR 0x0009 /* section header table */ 202 #define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */ 203 204 #define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */ 205 206 #ifdef _KERNEL 207 #define MD_FETCH(mdp, info, type) ({ \ 208 type *__p; \ 209 __p = (type *)preload_search_info((mdp), MODINFO_METADATA | (info)); \ 210 __p ? *__p : 0; \ 211 }) 212 #endif 213 214 #define LINKER_HINTS_VERSION 1 /* linker.hints file version */ 215 216 #ifdef _KERNEL 217 218 /* 219 * Module lookup 220 */ 221 extern caddr_t preload_metadata; 222 extern caddr_t preload_search_by_name(const char *_name); 223 extern caddr_t preload_search_by_type(const char *_type); 224 extern caddr_t preload_search_next_name(caddr_t _base); 225 extern caddr_t preload_search_info(caddr_t _mod, int _inf); 226 extern void preload_delete_name(const char *_name); 227 extern void preload_bootstrap_relocate(vm_offset_t _offset); 228 229 #ifdef KLD_DEBUG 230 231 extern int kld_debug; 232 #define KLD_DEBUG_FILE 1 /* file load/unload */ 233 #define KLD_DEBUG_SYM 2 /* symbol lookup */ 234 235 #define KLD_DPF(cat, args) \ 236 do { \ 237 if (kld_debug & KLD_DEBUG_##cat) printf args; \ 238 } while (0) 239 240 #else 241 242 #define KLD_DPF(cat, args) 243 244 #endif 245 246 typedef Elf_Addr elf_lookup_fn(linker_file_t, Elf_Size, int); 247 248 /* Support functions */ 249 int elf_reloc(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu); 250 int elf_reloc_local(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu); 251 const Elf_Sym *elf_get_sym(linker_file_t _lf, Elf_Size _symidx); 252 const char *elf_get_symname(linker_file_t _lf, Elf_Size _symidx); 253 254 int elf_cpu_load_file(linker_file_t); 255 int elf_cpu_unload_file(linker_file_t); 256 257 /* values for type */ 258 #define ELF_RELOC_REL 1 259 #define ELF_RELOC_RELA 2 260 261 /* 262 * This is version 1 of the KLD file status structure. It is identified 263 * by it's _size_ in the version field. 264 */ 265 struct kld_file_stat_1 { 266 int version; /* set to sizeof(linker_file_stat) */ 267 char name[MAXPATHLEN]; 268 int refs; 269 int id; 270 caddr_t address; /* load address */ 271 size_t size; /* size in bytes */ 272 }; 273 #endif /* _KERNEL */ 274 275 struct kld_file_stat { 276 int version; /* set to sizeof(linker_file_stat) */ 277 char name[MAXPATHLEN]; 278 int refs; 279 int id; 280 caddr_t address; /* load address */ 281 size_t size; /* size in bytes */ 282 char pathname[MAXPATHLEN]; 283 }; 284 285 struct kld_sym_lookup { 286 int version; /* set to sizeof(struct kld_sym_lookup) */ 287 char *symname; /* Symbol name we are looking up */ 288 u_long symvalue; 289 size_t symsize; 290 }; 291 #define KLDSYM_LOOKUP 1 292 293 /* 294 * Flags for kldunloadf() and linker_file_unload() 295 */ 296 #define LINKER_UNLOAD_NORMAL 0 297 #define LINKER_UNLOAD_FORCE 1 298 299 #ifndef _KERNEL 300 301 #include <sys/cdefs.h> 302 303 __BEGIN_DECLS 304 int kldload(const char* _file); 305 int kldunload(int _fileid); 306 int kldunloadf(int _fileid, int flags); 307 int kldfind(const char* _file); 308 int kldnext(int _fileid); 309 int kldstat(int _fileid, struct kld_file_stat* _stat); 310 int kldfirstmod(int _fileid); 311 int kldsym(int _fileid, int _cmd, void *_data); 312 __END_DECLS 313 314 #endif 315 316 #endif /* !_SYS_LINKER_H_ */ 317