freebsd-dev/sys/kern/kern_module.c
Julian Elischer b40ce4165d KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after:    ha ha ha ha
2001-09-12 08:38:13 +00:00

373 lines
8.0 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/eventhandler.h>
#include <sys/malloc.h>
#include <sys/sysproto.h>
#include <sys/sysent.h>
#include <sys/module.h>
#include <sys/linker.h>
#include <sys/proc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
static MALLOC_DEFINE(M_MODULE, "module", "module data structures");
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 */
modspecific_t data; /* module specific data */
};
#define MOD_EVENT(mod, type) (mod)->handler((mod), (type), (mod)->arg)
static modulelist_t modules;
static int nextid = 1;
static void module_shutdown(void*, int);
static int
modevent_nop(module_t mod, int what, void* arg)
{
return 0;
}
static void
module_init(void* arg)
{
TAILQ_INIT(&modules);
EVENTHANDLER_REGISTER(shutdown_post_sync, module_shutdown, NULL,
SHUTDOWN_PRI_DEFAULT);
}
SYSINIT(module, SI_SUB_KLD, SI_ORDER_FIRST, module_init, 0);
static void
module_shutdown(void* arg1, int arg2)
{
module_t mod;
TAILQ_FOREACH(mod, &modules, link)
MOD_EVENT(mod, MOD_SHUTDOWN);
}
void
module_register_init(const void *arg)
{
const moduledata_t* data = (const moduledata_t*) arg;
int error;
module_t mod;
mod = module_lookupbyname(data->name);
if (mod == NULL)
panic("module_register_init: module named %s not found\n", data->name);
error = MOD_EVENT(mod, MOD_LOAD);
if (error) {
MOD_EVENT(mod, MOD_UNLOAD);
module_release(mod);
printf("module_register_init: MOD_LOAD (%s, %lx, %p) error %d\n",
data->name, (u_long)(uintfptr_t)data->evhand, data->priv, error);
}
}
int
module_register(const moduledata_t *data, linker_file_t container)
{
size_t namelen;
module_t newmod;
newmod = module_lookupbyname(data->name);
if (newmod != NULL) {
printf("module_register: module %s already exists!\n", data->name);
return EEXIST;
}
namelen = strlen(data->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, data->name);
newmod->handler = data->evhand ? data->evhand : modevent_nop;
newmod->arg = data->priv;
bzero(&newmod->data, sizeof(newmod->data));
TAILQ_INSERT_TAIL(&modules, newmod, link);
if (container)
TAILQ_INSERT_TAIL(&container->modules, newmod, flink);
newmod->file = container;
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;
TAILQ_FOREACH(mod, &modules, link) {
if (!strcmp(mod->name, name))
return mod;
}
return 0;
}
module_t
module_lookupbyid(int modid)
{
module_t mod;
TAILQ_FOREACH(mod, &modules, 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);
}
void
module_setspecific(module_t mod, modspecific_t *datap)
{
mod->data = *datap;
}
/*
* Syscalls.
*/
/*
* MPSAFE
*/
int
modnext(struct thread *td, struct modnext_args *uap)
{
module_t mod;
int error = 0;
mtx_lock(&Giant);
td->td_retval[0] = -1;
if (SCARG(uap, modid) == 0) {
mod = TAILQ_FIRST(&modules);
if (mod)
td->td_retval[0] = mod->id;
else
error = ENOENT;
goto done2;
}
mod = module_lookupbyid(SCARG(uap, modid));
if (mod == NULL) {
error = ENOENT;
goto done2;
}
if (TAILQ_NEXT(mod, link))
td->td_retval[0] = TAILQ_NEXT(mod, link)->id;
else
td->td_retval[0] = 0;
done2:
mtx_unlock(&Giant);
return (error);
}
/*
* MPSAFE
*/
int
modfnext(struct thread *td, struct modfnext_args *uap)
{
module_t mod;
int error;
td->td_retval[0] = -1;
mtx_lock(&Giant);
mod = module_lookupbyid(SCARG(uap, modid));
if (mod == NULL) {
error = ENOENT;
} else {
error = 0;
if (TAILQ_NEXT(mod, flink))
td->td_retval[0] = TAILQ_NEXT(mod, flink)->id;
else
td->td_retval[0] = 0;
}
mtx_unlock(&Giant);
return (error);
}
struct module_stat_v1 {
int version; /* set to sizeof(struct module_stat) */
char name[MAXMODNAME];
int refs;
int id;
};
/*
* MPSAFE
*/
int
modstat(struct thread *td, struct modstat_args *uap)
{
module_t mod;
int error = 0;
int namelen;
int version;
struct module_stat* stat;
mtx_lock(&Giant);
mod = module_lookupbyid(SCARG(uap, modid));
if (mod == NULL) {
error = ENOENT;
goto out;
}
stat = SCARG(uap, stat);
/*
* Check the version of the user's structure.
*/
if ((error = copyin(&stat->version, &version, sizeof(version))) != 0)
goto out;
if (version != sizeof(struct module_stat_v1)
&& 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)) != 0)
goto out;
if ((error = copyout(&mod->refs, &stat->refs, sizeof(int))) != 0)
goto out;
if ((error = copyout(&mod->id, &stat->id, sizeof(int))) != 0)
goto out;
/*
* >v1 stat includes module data.
*/
if (version == sizeof(struct module_stat)) {
if ((error = copyout(&mod->data, &stat->data, sizeof(mod->data))) != 0)
goto out;
}
td->td_retval[0] = 0;
out:
mtx_unlock(&Giant);
return error;
}
/*
* MPSAFE
*/
int
modfind(struct thread *td, struct modfind_args *uap)
{
int error = 0;
char name[MAXMODNAME];
module_t mod;
if ((error = copyinstr(SCARG(uap, name), name, sizeof name, 0)) != 0)
goto out;
mtx_lock(&Giant);
mod = module_lookupbyname(name);
if (mod == NULL)
error = ENOENT;
else
td->td_retval[0] = mod->id;
mtx_unlock(&Giant);
out:
return error;
}