freebsd-dev/sys/kern/kern_module.c
Doug Rabson cea6c86c11 This is the kernel linker. To use it, you will first need to apply
the patches in freefall:/home/dfr/ld.diffs to your ld sources and set
BINFORMAT to aoutkld when linking the kernel.

Library changes and userland utilities will appear in a later commit.
1997-05-07 16:05:47 +00:00

305 lines
6.7 KiB
C

/*-
* 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.
*
* $Id$
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/queue.h>
#include <sys/libkern.h>
#include <sys/malloc.h>
#include <sys/sysproto.h>
#include <sys/sysent.h>
#include <sys/module.h>
#include <sys/linker.h>
#define M_MODULE M_TEMP /* XXX */
typedef TAILQ_HEAD(, module) modulelist_t;
struct module {
TAILQ_ENTRY(module) link; /* chain together all modules */
TAILQ_ENTRY(module) flink; /* all modules in a file */
struct linker_file* file; /* file which contains this module */
int refs; /* reference count */
int id; /* unique id number */
char *name; /* module name */
modeventhand_t handler; /* event handler */
void *arg; /* argument for handler */
};
#define MOD_EVENT(mod, type) (mod)->handler((mod), (type), (mod)->arg)
static modulelist_t modules;
static int nextid = 1;
static void module_shutdown(int, void*);
static void
module_init(void* arg)
{
TAILQ_INIT(&modules);
at_shutdown(module_shutdown, 0, SHUTDOWN_POST_SYNC);
}
SYSINIT(module, SI_SUB_KMEM, SI_ORDER_ANY, module_init, 0);
static void
module_shutdown(int arg1, void* arg2)
{
module_t mod;
int error;
for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link))
MOD_EVENT(mod, MOD_SHUTDOWN);
}
void
module_register_static(void *arg)
{
moduledata_t* data = (moduledata_t*) arg;
int error;
if (error = module_register(data->name, data->evhand, data->priv))
printf("module_register_static: module_register(%s, %x, %x) returned %d",
data->name, data->evhand, data->priv, error);
}
int
module_register(const char* name, modeventhand_t handler, void* arg)
{
size_t namelen;
module_t newmod;
int error;
namelen = strlen(name) + 1;
newmod = (module_t) malloc(sizeof(struct module) + namelen,
M_MODULE, M_WAITOK);
if (newmod == 0)
return ENOMEM;
newmod->refs = 1;
newmod->id = nextid++;
newmod->name = (char *) (newmod + 1);
strcpy(newmod->name, name);
newmod->handler = handler;
newmod->arg = arg;
TAILQ_INSERT_TAIL(&modules, newmod, link);
if (linker_current_file) {
TAILQ_INSERT_TAIL(&linker_current_file->modules, newmod, flink);
newmod->file = linker_current_file;
} else
newmod->file = 0;
if (error = MOD_EVENT(newmod, MOD_LOAD)) {
module_release(newmod);
return error;
}
return 0;
}
void
module_reference(module_t mod)
{
MOD_DPF(REFS, ("module_reference: before, refs=%d\n", mod->refs));
mod->refs++;
}
void
module_release(module_t mod)
{
if (mod->refs <= 0)
panic("module_release: bad reference count");
MOD_DPF(REFS, ("module_release: before, refs=%d\n", mod->refs));
mod->refs--;
if (mod->refs == 0) {
TAILQ_REMOVE(&modules, mod, link);
if (mod->file) {
TAILQ_REMOVE(&mod->file->modules, mod, flink);
}
free(mod, M_MODULE);
}
}
module_t
module_lookupbyname(const char* name)
{
module_t mod;
for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) {
if (!strcmp(mod->name, name))
return mod;
}
return 0;
}
module_t
module_lookupbyid(int modid)
{
module_t mod;
for (mod = TAILQ_FIRST(&modules); mod; mod = TAILQ_NEXT(mod, link)) {
if (mod->id == modid)
return mod;
}
return 0;
}
int
module_unload(module_t mod)
{
return MOD_EVENT(mod, MOD_UNLOAD);
}
int
module_getid(module_t mod)
{
return mod->id;
}
module_t
module_getfnext(module_t mod)
{
return TAILQ_NEXT(mod, flink);
}
/*
* Syscalls.
*/
int
modnext(struct proc* p, struct modnext_args* uap, int* retval)
{
module_t mod;
*retval = -1;
if (SCARG(uap, modid) == 0) {
mod = TAILQ_FIRST(&modules);
if (mod) {
*retval = mod->id;
return 0;
} else
return ENOENT;
}
mod = module_lookupbyid(SCARG(uap, modid));
if (!mod)
return ENOENT;
if (TAILQ_NEXT(mod, link))
*retval = TAILQ_NEXT(mod, link)->id;
else
*retval = 0;
return 0;
}
int
modfnext(struct proc* p, struct modfnext_args* uap, int* retval)
{
module_t mod;
*retval = -1;
mod = module_lookupbyid(SCARG(uap, modid));
if (!mod)
return ENOENT;
if (TAILQ_NEXT(mod, flink))
*retval = TAILQ_NEXT(mod, flink)->id;
else
*retval = 0;
return 0;
}
int
modstat(struct proc* p, struct modstat_args* uap, int* retval)
{
module_t mod;
int error = 0;
int namelen;
int version;
struct module_stat* stat;
mod = module_lookupbyid(SCARG(uap, modid));
if (!mod)
return ENOENT;
stat = SCARG(uap, stat);
/*
* Check the version of the user's structure.
*/
if (error = copyin(&stat->version, &version, sizeof(version)))
goto out;
if (version != sizeof(struct module_stat)) {
error = EINVAL;
goto out;
}
namelen = strlen(mod->name) + 1;
if (namelen > MAXMODNAME)
namelen = MAXMODNAME;
if (error = copyout(mod->name, &stat->name[0], namelen))
goto out;
if (error = copyout(&mod->refs, &stat->refs, sizeof(int)))
goto out;
if (error = copyout(&mod->id, &stat->id, sizeof(int)))
goto out;
*retval = 0;
out:
return error;
}
int
modfind(struct proc* p, struct modfind_args* uap, int* retval)
{
int error = 0;
char name[MAXMODNAME];
module_t mod;
if (error = copyinstr(SCARG(uap, name), name, sizeof name, 0))
goto out;
mod = module_lookupbyname(name);
if (!mod)
error = ENOENT;
else
*retval = mod->id;
out:
return error;
}