/*-
* Copyright (c) 1997 Doug Rabson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _SYS_LINKER_H_
#define _SYS_LINKER_H_
#ifdef KERNEL
#include <machine/elf.h>
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_LINKER);
#endif
/*
* Object representing a file which has been loaded by the linker.
*/
typedef struct linker_file* linker_file_t;
typedef TAILQ_HEAD(, linker_file) linker_file_list_t;
typedef caddr_t linker_sym_t; /* opaque symbol */
typedef c_caddr_t c_linker_sym_t; /* const opaque symbol */
/*
* expanded out linker_sym_t
*/
typedef struct linker_symval {
const char* name;
caddr_t value;
size_t size;
} linker_symval_t;
struct linker_file_ops {
/*
* Lookup a symbol in the file's symbol table. If the symbol is
* not found then return ENOENT, otherwise zero. If the symbol
* found is a common symbol, return with *address set to zero and
* *size set to the size of the common space required. Otherwise
* set *address the value of the symbol.
*/
int (*lookup_symbol)(linker_file_t, const char* name,
c_linker_sym_t* sym);
int (*symbol_values)(linker_file_t, c_linker_sym_t,
linker_symval_t*);
int (*search_symbol)(linker_file_t, caddr_t value,
c_linker_sym_t* sym, long* diffp);
/*
* Unload a file, releasing dependancies and freeing storage.
*/
void (*unload)(linker_file_t);
};
struct common_symbol {
STAILQ_ENTRY(common_symbol) link;
char* name;
caddr_t address;
};
struct linker_file {
int refs; /* reference count */
int userrefs; /* kldload(2) count */
int flags;
#define LINKER_FILE_LINKED 0x1 /* file has been fully linked */
TAILQ_ENTRY(linker_file) link; /* list of all loaded files */
char* filename; /* file which was loaded */
int id; /* unique id */
caddr_t address; /* load address */
size_t size; /* size of file */
int ndeps; /* number of dependancies */
linker_file_t* deps; /* list of dependancies */
STAILQ_HEAD(, common_symbol) common; /* list of common symbols */
TAILQ_HEAD(, module) modules; /* modules in this file */
void* priv; /* implementation data */
struct linker_file_ops* ops;
};
/*
* Object implementing a class of file (a.out, elf, etc.)
*/
typedef struct linker_class *linker_class_t;
typedef TAILQ_HEAD(, linker_class) linker_class_list_t;
struct linker_class_ops {
/*
* Load a file, returning the new linker_file_t in *result. If
* the class does not recognise the file type, zero should be
* returned, without modifying *result. If the file is
* recognised, the file should be loaded, *result set to the new
* file and zero returned. If some other error is detected an
* appropriate errno should be returned.
*/
int (*load_file)(const char* filename, linker_file_t* result);
};
struct linker_class {
TAILQ_ENTRY(linker_class) link; /* list of all file classes */
const char* desc; /* description (e.g. "a.out") */
void* priv; /* implementation data */
struct linker_class_ops *ops;
};
/*
* The file which is currently loading. Used to register modules with
* the files which contain them.
*/
extern linker_file_t linker_current_file;
/*
* The "file" for the kernel.
*/
extern linker_file_t linker_kernel_file;
/*
* Add a new file class to the linker.
*/
int linker_add_class(const char* desc, void* priv,
struct linker_class_ops* ops);
/*
* Load a file, trying each file class until one succeeds.
*/
int linker_load_file(const char* filename, linker_file_t* result);
/*
* Find a currently loaded file given its filename.
*/
linker_file_t linker_find_file_by_name(const char* filename);
/*
* Find a currently loaded file given its file id.
*/
linker_file_t linker_find_file_by_id(int fileid);
/*
* Called from a class handler when a file is laoded.
*/
linker_file_t linker_make_file(const char* filename, void* priv,
struct linker_file_ops* ops);
/*
* Unload a file, freeing up memory.
*/
int linker_file_unload(linker_file_t file);
/*
* Add a dependancy to a file.
*/
int linker_file_add_dependancy(linker_file_t file, linker_file_t dep);
/*
* Lookup a symbol in a file. If deps is TRUE, look in dependancies
* if not found in file.
*/
caddr_t linker_file_lookup_symbol(linker_file_t file, const char* name,
int deps);
/*
* Search the linker path for the module. Return the full pathname in
* a malloc'ed buffer.
*/
char *linker_search_path(const char *filename);
/*
* DDB Helpers, tuned specifically for ddb/db_kld.c
*/
int linker_ddb_lookup(const char *symstr, c_linker_sym_t *sym);
int linker_ddb_search_symbol(caddr_t value, c_linker_sym_t *sym, long *diffp);
int linker_ddb_symbol_values(c_linker_sym_t sym, linker_symval_t *symval);
#endif /* KERNEL */
/*
* Module information subtypes
*/
#define MODINFO_END 0x0000 /* End of list */
#define MODINFO_NAME 0x0001 /* Name of module (string) */
#define MODINFO_TYPE 0x0002 /* Type of module (string) */
#define MODINFO_ADDR 0x0003 /* Loaded address */
#define MODINFO_SIZE 0x0004 /* Size of module */
#define MODINFO_EMPTY 0x0005 /* Has been deleted */
#define MODINFO_ARGS 0x0006 /* Parameters string */
#define MODINFO_METADATA 0x8000 /* Module-specfic */
#define MODINFOMD_AOUTEXEC 0x0001 /* a.out exec header */
#define MODINFOMD_ELFHDR 0x0002 /* ELF header */
#define MODINFOMD_SSYM 0x0003 /* start of symbols */
#define MODINFOMD_ESYM 0x0004 /* end of symbols */
#define MODINFOMD_DYNAMIC 0x0005 /* _DYNAMIC pointer */
#define MODINFOMD_NOCOPY 0x8000 /* don't copy this metadata to the kernel */
#define MODINFOMD_DEPLIST (0x4001 | MODINFOMD_NOCOPY) /* depends on */
#ifdef KERNEL
/*
* Module lookup
*/
extern caddr_t preload_metadata;
extern caddr_t preload_search_by_name(const char *name);
extern caddr_t preload_search_by_type(const char *type);
extern caddr_t preload_search_next_name(caddr_t base);
extern caddr_t preload_search_info(caddr_t mod, int inf);
extern void preload_delete_name(const char *name);
extern void preload_bootstrap_relocate(vm_offset_t offset);
#ifdef KLD_DEBUG
extern int kld_debug;
#define KLD_DEBUG_FILE 1 /* file load/unload */
#define KLD_DEBUG_SYM 2 /* symbol lookup */
#define KLD_DPF(cat, args) \
do { \
if (kld_debug & KLD_DEBUG_##cat) printf args; \
} while (0)
#else
#define KLD_DPF(cat, args)
#endif
/* Support functions */
int elf_reloc(linker_file_t lf, const void *rel, int type, const char *sym);
/* values for type */
#define ELF_RELOC_REL 1
#define ELF_RELOC_RELA 2
#endif /* KERNEL */
struct kld_file_stat {
int version; /* set to sizeof(linker_file_stat) */
char name[MAXPATHLEN];
int refs;
int id;
caddr_t address; /* load address */
size_t size; /* size in bytes */
};
struct kld_sym_lookup {
int version; /* set to sizeof(struct kld_sym_lookup) */
char *symname; /* Symbol name we are looking up */
u_long symvalue;
size_t symsize;
};
#define KLDSYM_LOOKUP 1
#ifndef KERNEL
#include <sys/cdefs.h>
__BEGIN_DECLS
int kldload(const char* file);
int kldunload(int fileid);
int kldfind(const char* file);
int kldnext(int fileid);
int kldstat(int fileid, struct kld_file_stat* stat);
int kldfirstmod(int fileid);
int kldsym(int _fileid, int _cmd, void *_data);
__END_DECLS
#endif
#endif /* !_SYS_LINKER_H_ */
