112 lines
3.7 KiB
C
112 lines
3.7 KiB
C
/*-
|
|
* Copyright (c) 1999 Assar Westerlund
|
|
* 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/sysproto.h>
|
|
#include <sys/sysent.h>
|
|
#include <sys/syscall.h>
|
|
#include <sys/module.h>
|
|
|
|
/*
|
|
* Acts like "nosys" but can be identified in sysent for dynamic call
|
|
* number assignment for a limited number of calls.
|
|
*
|
|
* Place holder for system call slots reserved for loadable modules.
|
|
*/
|
|
int
|
|
lkmnosys(struct proc *p, struct nosys_args *args)
|
|
{
|
|
return(nosys(p, args));
|
|
}
|
|
|
|
int
|
|
syscall_register(int *offset, struct sysent *new_sysent,
|
|
struct sysent *old_sysent)
|
|
{
|
|
if (*offset == NO_SYSCALL) {
|
|
int i;
|
|
|
|
for (i = 1; i < SYS_MAXSYSCALL; ++i)
|
|
if (sysent[i].sy_call == (sy_call_t *)lkmnosys)
|
|
break;
|
|
if (i == SYS_MAXSYSCALL)
|
|
return ENFILE;
|
|
*offset = i;
|
|
} else if (*offset < 0 || *offset >= SYS_MAXSYSCALL)
|
|
return EINVAL;
|
|
else if (sysent[*offset].sy_call != (sy_call_t *)lkmnosys)
|
|
return EEXIST;
|
|
|
|
*old_sysent = sysent[*offset];
|
|
sysent[*offset] = *new_sysent;
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
syscall_deregister(int *offset, struct sysent *old_sysent)
|
|
{
|
|
if (*offset)
|
|
sysent[*offset] = *old_sysent;
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
syscall_module_handler(struct module *mod, int what, void *arg)
|
|
{
|
|
struct syscall_module_data *data = (struct syscall_module_data*)arg;
|
|
modspecific_t ms;
|
|
int error;
|
|
|
|
switch (what) {
|
|
case MOD_LOAD :
|
|
error = syscall_register(data->offset, data->new_sysent,
|
|
&data->old_sysent);
|
|
if (error)
|
|
return error;
|
|
ms.intval = *data->offset;
|
|
module_setspecific(mod, &ms);
|
|
if (data->chainevh)
|
|
error = data->chainevh(mod, what, data->chainarg);
|
|
return error;
|
|
|
|
case MOD_UNLOAD :
|
|
if (data->chainevh) {
|
|
error = data->chainevh(mod, what, data->chainarg);
|
|
if (error)
|
|
return error;
|
|
}
|
|
error = syscall_deregister(data->offset, &data->old_sysent);
|
|
return error;
|
|
}
|
|
|
|
if (data->chainevh)
|
|
return data->chainevh(mod, what, data->chainarg);
|
|
else
|
|
return 0;
|
|
}
|