2 * Copyright (c) 1997-2000 Doug Rabson
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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
29 #ifndef _SYS_LINKER_H_
30 #define _SYS_LINKER_H_
34 #include <machine/elf.h>
38 MALLOC_DECLARE(M_LINKER);
42 * Object representing a file which has been loaded by the linker.
44 typedef struct linker_file* linker_file_t;
45 typedef TAILQ_HEAD(, linker_file) linker_file_list_t;
47 typedef caddr_t linker_sym_t; /* opaque symbol */
48 typedef c_caddr_t c_linker_sym_t; /* const opaque symbol */
49 typedef int (*linker_function_name_callback_t)(const char *, void *);
52 * expanded out linker_sym_t
54 typedef struct linker_symval {
60 struct common_symbol {
61 STAILQ_ENTRY(common_symbol) link;
68 int refs; /* reference count */
69 int userrefs; /* kldload(2) count */
71 #define LINKER_FILE_LINKED 0x1 /* file has been fully linked */
72 TAILQ_ENTRY(linker_file) link; /* list of all loaded files */
73 char* filename; /* file which was loaded */
74 int id; /* unique id */
75 caddr_t address; /* load address */
76 size_t size; /* size of file */
77 int ndeps; /* number of dependencies */
78 linker_file_t* deps; /* list of dependencies */
79 STAILQ_HEAD(, common_symbol) common; /* list of common symbols */
80 TAILQ_HEAD(, module) modules; /* modules in this file */
81 TAILQ_ENTRY(linker_file) loaded; /* preload dependency support */
85 * Object implementing a class of file (a.out, elf, etc.)
87 typedef struct linker_class *linker_class_t;
88 typedef TAILQ_HEAD(, linker_class) linker_class_list_t;
92 TAILQ_ENTRY(linker_class) link; /* list of all file classes */
96 * The "file" for the kernel.
98 extern linker_file_t linker_kernel_file;
101 * Add a new file class to the linker.
103 int linker_add_class(linker_class_t _cls);
106 * Load a file, trying each file class until one succeeds.
108 int linker_load_file(const char* _filename, linker_file_t* _result);
111 * Obtain a reference to a module, loading it if required.
113 int linker_reference_module(const char* _modname, linker_file_t* _result);
116 * Find a currently loaded file given its filename.
118 linker_file_t linker_find_file_by_name(const char* _filename);
121 * Find a currently loaded file given its file id.
123 linker_file_t linker_find_file_by_id(int _fileid);
126 * Called from a class handler when a file is laoded.
128 linker_file_t linker_make_file(const char* _filename, linker_class_t _cls);
131 * Unload a file, freeing up memory.
133 int linker_file_unload(linker_file_t _file);
136 * Add a dependency to a file.
138 int linker_file_add_dependency(linker_file_t _file, linker_file_t _dep);
141 * Lookup a symbol in a file. If deps is TRUE, look in dependencies
142 * if not found in file.
144 caddr_t linker_file_lookup_symbol(linker_file_t _file, const char* _name,
148 * Lookup a linker set in a file. Return pointers to the first entry,
149 * last + 1, and count of entries. Use: for (p = start; p < stop; p++) {}
150 * void *start is really: "struct yoursetmember ***start;"
152 int linker_file_lookup_set(linker_file_t _file, const char *_name,
153 void *_start, void *_stop, int *_count);
156 * This routine is responsible for finding dependencies of userland
157 * initiated kldload(2)'s of files.
159 int linker_load_dependencies(linker_file_t _lf);
162 * DDB Helpers, tuned specifically for ddb/db_kld.c
164 int linker_ddb_lookup(const char *_symstr, c_linker_sym_t *_sym);
165 int linker_ddb_search_symbol(caddr_t _value, c_linker_sym_t *_sym,
167 int linker_ddb_symbol_values(c_linker_sym_t _sym, linker_symval_t *_symval);
173 * Module information subtypes
175 #define MODINFO_END 0x0000 /* End of list */
176 #define MODINFO_NAME 0x0001 /* Name of module (string) */
177 #define MODINFO_TYPE 0x0002 /* Type of module (string) */
178 #define MODINFO_ADDR 0x0003 /* Loaded address */
179 #define MODINFO_SIZE 0x0004 /* Size of module */
180 #define MODINFO_EMPTY 0x0005 /* Has been deleted */
181 #define MODINFO_ARGS 0x0006 /* Parameters string */
182 #define MODINFO_METADATA 0x8000 /* Module-specfic */
184 #define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */
185 #define MODINFOMD_ELFHDR 0x0002 /* ELF header */
186 #define MODINFOMD_SSYM 0x0003 /* start of symbols */
187 #define MODINFOMD_ESYM 0x0004 /* end of symbols */
188 #define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */
189 #define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */
191 #define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */
193 #define LINKER_HINTS_VERSION 1 /* linker.hints file version */
200 extern caddr_t preload_metadata;
201 extern caddr_t preload_search_by_name(const char *_name);
202 extern caddr_t preload_search_by_type(const char *_type);
203 extern caddr_t preload_search_next_name(caddr_t _base);
204 extern caddr_t preload_search_info(caddr_t _mod, int _inf);
205 extern void preload_delete_name(const char *_name);
206 extern void preload_bootstrap_relocate(vm_offset_t _offset);
210 extern int kld_debug;
211 #define KLD_DEBUG_FILE 1 /* file load/unload */
212 #define KLD_DEBUG_SYM 2 /* symbol lookup */
214 #define KLD_DPF(cat, args) \
216 if (kld_debug & KLD_DEBUG_##cat) printf args; \
221 #define KLD_DPF(cat, args)
225 /* Support functions */
226 int elf_reloc(linker_file_t _lf, const void *_rel, int _type,
228 /* values for type */
229 #define ELF_RELOC_REL 1
230 #define ELF_RELOC_RELA 2
234 struct kld_file_stat {
235 int version; /* set to sizeof(linker_file_stat) */
236 char name[MAXPATHLEN];
239 caddr_t address; /* load address */
240 size_t size; /* size in bytes */
243 struct kld_sym_lookup {
244 int version; /* set to sizeof(struct kld_sym_lookup) */
245 char *symname; /* Symbol name we are looking up */
249 #define KLDSYM_LOOKUP 1
253 #include <sys/cdefs.h>
256 int kldload(const char* _file);
257 int kldunload(int _fileid);
258 int kldfind(const char* _file);
259 int kldnext(int _fileid);
260 int kldstat(int _fileid, struct kld_file_stat* _stat);
261 int kldfirstmod(int _fileid);
262 int kldsym(int _fileid, int _cmd, void *_data);
267 #endif /* !_SYS_LINKER_H_ */