FreeBSD-5.3/sys/kern/subr_module.c
/*-
* Copyright (c) 1998 Michael Smith
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/kern/subr_module.c,v 1.8 2003/06/11 00:56:57 obrien Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/linker.h>
/*
* Preloaded module support
*/
caddr_t preload_metadata;
/*
* Search for the preloaded module (name)
*/
caddr_t
preload_search_by_name(const char *name)
{
caddr_t curp;
u_int32_t *hdr;
int next;
if (preload_metadata != NULL) {
curp = preload_metadata;
for (;;) {
hdr = (u_int32_t *)curp;
if (hdr[0] == 0 && hdr[1] == 0)
break;
/* Search for a MODINFO_NAME field */
if ((hdr[0] == MODINFO_NAME) &&
!strcmp(name, curp + sizeof(u_int32_t) * 2))
return(curp);
/* skip to next field */
next = sizeof(u_int32_t) * 2 + hdr[1];
next = roundup(next, sizeof(u_long));
curp += next;
}
}
return(NULL);
}
/*
* Search for the first preloaded module of (type)
*/
caddr_t
preload_search_by_type(const char *type)
{
caddr_t curp, lname;
u_int32_t *hdr;
int next;
if (preload_metadata != NULL) {
curp = preload_metadata;
lname = NULL;
for (;;) {
hdr = (u_int32_t *)curp;
if (hdr[0] == 0 && hdr[1] == 0)
break;
/* remember the start of each record */
if (hdr[0] == MODINFO_NAME)
lname = curp;
/* Search for a MODINFO_TYPE field */
if ((hdr[0] == MODINFO_TYPE) &&
!strcmp(type, curp + sizeof(u_int32_t) * 2))
return(lname);
/* skip to next field */
next = sizeof(u_int32_t) * 2 + hdr[1];
next = roundup(next, sizeof(u_long));
curp += next;
}
}
return(NULL);
}
/*
* Walk through the preloaded module list
*/
caddr_t
preload_search_next_name(caddr_t base)
{
caddr_t curp;
u_int32_t *hdr;
int next;
if (preload_metadata != NULL) {
/* Pick up where we left off last time */
if (base) {
/* skip to next field */
curp = base;
hdr = (u_int32_t *)curp;
next = sizeof(u_int32_t) * 2 + hdr[1];
next = roundup(next, sizeof(u_long));
curp += next;
} else
curp = preload_metadata;
for (;;) {
hdr = (u_int32_t *)curp;
if (hdr[0] == 0 && hdr[1] == 0)
break;
/* Found a new record? */
if (hdr[0] == MODINFO_NAME)
return curp;
/* skip to next field */
next = sizeof(u_int32_t) * 2 + hdr[1];
next = roundup(next, sizeof(u_long));
curp += next;
}
}
return(NULL);
}
/*
* Given a preloaded module handle (mod), return a pointer
* to the data for the attribute (inf).
*/
caddr_t
preload_search_info(caddr_t mod, int inf)
{
caddr_t curp;
u_int32_t *hdr;
u_int32_t type = 0;
int next;
curp = mod;
for (;;) {
hdr = (u_int32_t *)curp;
/* end of module data? */
if (hdr[0] == 0 && hdr[1] == 0)
break;
/*
* We give up once we've looped back to what we were looking at
* first - this should normally be a MODINFO_NAME field.
*/
if (type == 0) {
type = hdr[0];
} else {
if (hdr[0] == type)
break;
}
/*
* Attribute match? Return pointer to data.
* Consumer may safely assume that size value precedes
* data.
*/
if (hdr[0] == inf)
return(curp + (sizeof(u_int32_t) * 2));
/* skip to next field */
next = sizeof(u_int32_t) * 2 + hdr[1];
next = roundup(next, sizeof(u_long));
curp += next;
}
return(NULL);
}
/*
* Delete a preload record by name.
*/
void
preload_delete_name(const char *name)
{
caddr_t curp;
u_int32_t *hdr;
int next;
int clearing;
if (preload_metadata != NULL) {
clearing = 0;
curp = preload_metadata;
for (;;) {
hdr = (u_int32_t *)curp;
if (hdr[0] == 0 && hdr[1] == 0)
break;
/* Search for a MODINFO_NAME field */
if (hdr[0] == MODINFO_NAME) {
if (!strcmp(name, curp + sizeof(u_int32_t) * 2))
clearing = 1; /* got it, start clearing */
else if (clearing)
clearing = 0; /* at next one now.. better stop */
}
if (clearing)
hdr[0] = MODINFO_EMPTY;
/* skip to next field */
next = sizeof(u_int32_t) * 2 + hdr[1];
next = roundup(next, sizeof(u_long));
curp += next;
}
}
}
/* Called from locore on i386. Convert physical pointers to kvm. Sigh. */
void
preload_bootstrap_relocate(vm_offset_t offset)
{
caddr_t curp;
u_int32_t *hdr;
vm_offset_t *ptr;
int next;
if (preload_metadata != NULL) {
curp = preload_metadata;
for (;;) {
hdr = (u_int32_t *)curp;
if (hdr[0] == 0 && hdr[1] == 0)
break;
/* Deal with the ones that we know we have to fix */
switch (hdr[0]) {
case MODINFO_ADDR:
case MODINFO_METADATA|MODINFOMD_SSYM:
case MODINFO_METADATA|MODINFOMD_ESYM:
ptr = (vm_offset_t *)(curp + (sizeof(u_int32_t) * 2));
*ptr += offset;
break;
}
/* The rest is beyond us for now */
/* skip to next field */
next = sizeof(u_int32_t) * 2 + hdr[1];
next = roundup(next, sizeof(u_long));
curp += next;
}
}
}