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 int id; /* unique id */ 77 caddr_t address; /* load address */ 78 size_t size; /* size of file */ 79 int ndeps; /* number of dependencies */ 80 linker_file_t* deps; /* list of dependencies */ 81 STAILQ_HEAD(, common_symbol) common; /* list of common symbols */ 82 TAILQ_HEAD(, module) modules; /* modules in this file */ 83 TAILQ_ENTRY(linker_file) loaded; /* preload dependency support */ 84 }; 85 86 /* 87 * Object implementing a class of file (a.out, elf, etc.) 88 */ 89 typedef struct linker_class *linker_class_t; 90 typedef TAILQ_HEAD(, linker_class) linker_class_list_t; 91 92 struct linker_class { 93 KOBJ_CLASS_FIELDS; 94 TAILQ_ENTRY(linker_class) link; /* list of all file classes */ 95 }; 96 97 /* 98 * Function type used when iterating over the list of linker files. 99 */ 100 typedef int linker_predicate_t(linker_file_t, void *); 101 102 /* 103 * The "file" for the kernel. 104 */ 105 extern linker_file_t linker_kernel_file; 106 107 /* 108 * Obtain a reference to a module, loading it if required. 109 */ 110 int linker_reference_module(const char* _modname, struct mod_depend *_verinfo, 111 linker_file_t* _result); 112 113 /* 114 * Release a reference to a module, unloading it if there are no more 115 * references. Note that one should either provide a module name and 116 * optional version info or a linker file, but not both. 117 */ 118 int linker_release_module(const char *_modname, struct mod_depend *_verinfo, 119 linker_file_t _file); 120 121 /* 122 * Iterate over all of the currently loaded linker files calling the 123 * predicate function while the function returns 0. Returns the value 124 * returned by the last predicate function. 125 */ 126 int linker_file_foreach(linker_predicate_t *_predicate, void *_context); 127 128 /* 129 * Lookup a symbol in a file. If deps is TRUE, look in dependencies 130 * if not found in file. 131 */ 132 caddr_t linker_file_lookup_symbol(linker_file_t _file, const char* _name, 133 int _deps); 134 135 /* 136 * Lookup a linker set in a file. Return pointers to the first entry, 137 * last + 1, and count of entries. Use: for (p = start; p < stop; p++) {} 138 * void *start is really: "struct yoursetmember ***start;" 139 */ 140 int linker_file_lookup_set(linker_file_t _file, const char *_name, 141 void *_start, void *_stop, int *_count); 142 143 /* 144 * Functions soley for use by the linker class handlers. 145 */ 146 int linker_add_class(linker_class_t _cls); 147 int linker_file_unload(linker_file_t _file, int flags); 148 int linker_load_dependencies(linker_file_t _lf); 149 linker_file_t linker_make_file(const char* _filename, linker_class_t _cls); 150 151 /* 152 * DDB Helpers, tuned specifically for ddb/db_kld.c 153 */ 154 int linker_ddb_lookup(const char *_symstr, c_linker_sym_t *_sym); 155 int linker_ddb_search_symbol(caddr_t _value, c_linker_sym_t *_sym, 156 long *_diffp); 157 int linker_ddb_symbol_values(c_linker_sym_t _sym, linker_symval_t *_symval); 158 159 160 /* HWPMC helper */ 161 void *linker_hwpmc_list_objects(void); 162 163 #endif /* _KERNEL */ 164 165 /* 166 * Module information subtypes 167 */ 168 #define MODINFO_END 0x0000 /* End of list */ 169 #define MODINFO_NAME 0x0001 /* Name of module (string) */ 170 #define MODINFO_TYPE 0x0002 /* Type of module (string) */ 171 #define MODINFO_ADDR 0x0003 /* Loaded address */ 172 #define MODINFO_SIZE 0x0004 /* Size of module */ 173 #define MODINFO_EMPTY 0x0005 /* Has been deleted */ 174 #define MODINFO_ARGS 0x0006 /* Parameters string */ 175 #define MODINFO_METADATA 0x8000 /* Module-specfic */ 176 177 #define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */ 178 #define MODINFOMD_ELFHDR 0x0002 /* ELF header */ 179 #define MODINFOMD_SSYM 0x0003 /* start of symbols */ 180 #define MODINFOMD_ESYM 0x0004 /* end of symbols */ 181 #define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */ 182 /* These values are MD on these two platforms */ 183 #if !defined(__sparc64__) && !defined(__powerpc__) 184 #define MODINFOMD_ENVP 0x0006 /* envp[] */ 185 #define MODINFOMD_HOWTO 0x0007 /* boothowto */ 186 #define MODINFOMD_KERNEND 0x0008 /* kernend */ 187 #endif 188 #define MODINFOMD_SHDR 0x0009 /* section header table */ 189 #define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */ 190 191 #define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */ 192 193 #ifdef _KERNEL 194 #define MD_FETCH(mdp, info, type) ({ \ 195 type *__p; \ 196 __p = (type *)preload_search_info((mdp), MODINFO_METADATA | (info)); \ 197 __p ? *__p : 0; \ 198 }) 199 #endif 200 201 #define LINKER_HINTS_VERSION 1 /* linker.hints file version */ 202 203 #ifdef _KERNEL 204 205 /* 206 * Module lookup 207 */ 208 extern caddr_t preload_metadata; 209 extern caddr_t preload_search_by_name(const char *_name); 210 extern caddr_t preload_search_by_type(const char *_type); 211 extern caddr_t preload_search_next_name(caddr_t _base); 212 extern caddr_t preload_search_info(caddr_t _mod, int _inf); 213 extern void preload_delete_name(const char *_name); 214 extern void preload_bootstrap_relocate(vm_offset_t _offset); 215 216 #ifdef KLD_DEBUG 217 218 extern int kld_debug; 219 #define KLD_DEBUG_FILE 1 /* file load/unload */ 220 #define KLD_DEBUG_SYM 2 /* symbol lookup */ 221 222 #define KLD_DPF(cat, args) \ 223 do { \ 224 if (kld_debug & KLD_DEBUG_##cat) printf args; \ 225 } while (0) 226 227 #else 228 229 #define KLD_DPF(cat, args) 230 231 #endif 232 233 typedef Elf_Addr elf_lookup_fn(linker_file_t, Elf_Size, int); 234 235 /* Support functions */ 236 int elf_reloc(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu); 237 int elf_reloc_local(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu); 238 const Elf_Sym *elf_get_sym(linker_file_t _lf, Elf_Size _symidx); 239 const char *elf_get_symname(linker_file_t _lf, Elf_Size _symidx); 240 241 int elf_cpu_load_file(linker_file_t); 242 int elf_cpu_unload_file(linker_file_t); 243 244 /* values for type */ 245 #define ELF_RELOC_REL 1 246 #define ELF_RELOC_RELA 2 247 248 #endif /* _KERNEL */ 249 250 struct kld_file_stat { 251 int version; /* set to sizeof(linker_file_stat) */ 252 char name[MAXPATHLEN]; 253 int refs; 254 int id; 255 caddr_t address; /* load address */ 256 size_t size; /* size in bytes */ 257 }; 258 259 struct kld_sym_lookup { 260 int version; /* set to sizeof(struct kld_sym_lookup) */ 261 char *symname; /* Symbol name we are looking up */ 262 u_long symvalue; 263 size_t symsize; 264 }; 265 #define KLDSYM_LOOKUP 1 266 267 /* 268 * Flags for kldunloadf() and linker_file_unload() 269 */ 270 #define LINKER_UNLOAD_NORMAL 0 271 #define LINKER_UNLOAD_FORCE 1 272 273 #ifndef _KERNEL 274 275 #include <sys/cdefs.h> 276 277 __BEGIN_DECLS 278 int kldload(const char* _file); 279 int kldunload(int _fileid); 280 int kldunloadf(int _fileid, int flags); 281 int kldfind(const char* _file); 282 int kldnext(int _fileid); 283 int kldstat(int _fileid, struct kld_file_stat* _stat); 284 int kldfirstmod(int _fileid); 285 int kldsym(int _fileid, int _cmd, void *_data); 286 __END_DECLS 287 288 #endif 289 290 #endif /* !_SYS_LINKER_H_ */ 291