FreeBSD-5.3/lib/libdevinfo/devinfo.c
/*-
* Copyright (c) 2000 Michael Smith
* Copyright (c) 2000 BSDi
* 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/lib/libdevinfo/devinfo.c,v 1.4 2002/09/20 02:16:33 imp Exp $");
/*
* An interface to the FreeBSD kernel's bus/devce information interface.
*
* This interface is implemented with the
*
* hw.bus
* hw.bus.devices
* hw.bus.rman
*
* sysctls. The interface is not meant for general user application
* consumption.
*
* Device information is obtained by scanning a linear list of all devices
* maintained by the kernel. The actual device structure pointers are
* handed out as opaque handles in order to allow reconstruction of the
* logical toplogy in user space.
*
* Resource information is obtained by scanning the kernel's resource
* managers and fetching their contents. Ownership of resources is
* tracked using the device's structure pointer again as a handle.
*
* In order to ensure coherency of the library's picture of the kernel,
* a generation count is maintained by the kernel. The initial generation
* count is obtained (along with the interface version) from the hw.bus
* sysctl, and must be passed in with every request. If the generation
* number supplied by the library does not match the kernel's current
* generation number, the request is failed and the library must discard
* the data it has received and rescan.
*
* The information obtained from the kernel is exported to consumers of
* this library through a variety of interfaces.
*/
#include <sys/param.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#include <err.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "devinfo.h"
#include "devinfo_var.h"
static int devinfo_init_devices(int generation);
static int devinfo_init_resources(int generation);
TAILQ_HEAD(,devinfo_i_dev) devinfo_dev;
TAILQ_HEAD(,devinfo_i_rman) devinfo_rman;
TAILQ_HEAD(,devinfo_i_res) devinfo_res;
static int devinfo_initted = 0;
static int devinfo_generation = 0;
#if 0
# define debug(fmt, args...) \
fprintf(stderr, "%s:" fmt "\n", __FUNCTION__ , ##args)
#else
# define debug(fmt, args...)
#endif
/*
* Initialise our local database with the contents of the kernel's
* tables.
*/
int
devinfo_init(void)
{
struct u_businfo ubus;
size_t ub_size;
int error, retries;
if (!devinfo_initted) {
TAILQ_INIT(&devinfo_dev);
TAILQ_INIT(&devinfo_rman);
TAILQ_INIT(&devinfo_res);
}
/*
* Get the generation count and interface version, verify that we
* are compatible with the kernel.
*/
for (retries = 0; retries < 10; retries++) {
debug("get interface version");
ub_size = sizeof(ubus);
if (sysctlbyname("hw.bus.info", &ubus,
&ub_size, NULL, 0) != 0) {
warn("sysctlbyname(\"hw.bus.info\", ...) failed");
return(EINVAL);
}
if ((ub_size != sizeof(ubus)) ||
(ubus.ub_version != BUS_USER_VERSION)) {
warn("kernel bus interface version mismatch");
return(EINVAL);
}
debug("generation count is %d", ubus.ub_generation);
/*
* Don't rescan if the generation count hasn't changed.
*/
if (ubus.ub_generation == devinfo_generation)
return(0);
/*
* Generation count changed, rescan
*/
devinfo_free();
devinfo_initted = 0;
devinfo_generation = 0;
if ((error = devinfo_init_devices(ubus.ub_generation)) != 0) {
devinfo_free();
if (error == EINVAL)
continue;
break;
}
if ((error = devinfo_init_resources(ubus.ub_generation)) != 0) {
devinfo_free();
if (error == EINVAL)
continue;
break;
}
devinfo_initted = 1;
devinfo_generation = ubus.ub_generation;
return(0);
}
debug("scan failed after %d retries", retries);
errno = error;
return(1);
}
static int
devinfo_init_devices(int generation)
{
struct u_device udev;
struct devinfo_i_dev *dd;
int dev_idx;
int dev_ptr;
int name2oid[2];
int oid[CTL_MAXNAME + 12];
size_t oidlen, rlen;
char *name, *np, *fmt;
int error, hexmode;
/*
* Find the OID for the rman interface node.
* This is just the usual evil, undocumented sysctl juju.
*/
name2oid[0] = 0;
name2oid[1] = 3;
oidlen = sizeof(oid);
name = "hw.bus.devices";
error = sysctl(name2oid, 2, oid, &oidlen, name, strlen(name));
if (error < 0) {
warnx("can't find hw.bus.devices sysctl node");
return(ENOENT);
}
oidlen /= sizeof(int);
if (oidlen > CTL_MAXNAME) {
warnx("hw.bus.devices oid is too large");
return(EINVAL);
}
oid[oidlen++] = generation;
dev_ptr = oidlen++;
/*
* Scan devices.
*
* Stop after a fairly insane number to avoid death in the case
* of kernel corruption.
*/
for (dev_idx = 0; dev_idx < 1000; dev_idx++) {
/*
* Get the device information.
*/
oid[dev_ptr] = dev_idx;
rlen = sizeof(udev);
error = sysctl(oid, oidlen, &udev, &rlen, NULL, 0);
if (error < 0) {
if (errno == ENOENT) /* end of list */
break;
if (errno != EINVAL) /* gen count skip, restart */
warn("sysctl hw.bus.devices.%d", dev_idx);
return(errno);
}
if ((dd = malloc(sizeof(*dd))) == NULL)
return(ENOMEM);
dd->dd_dev.dd_handle = udev.dv_handle;
dd->dd_dev.dd_parent = udev.dv_parent;
snprintf(dd->dd_name, sizeof(dd->dd_name), "%s", udev.dv_name);
dd->dd_dev.dd_name = &dd->dd_name[0];
snprintf(dd->dd_desc, sizeof(dd->dd_desc), "%s", udev.dv_desc);
dd->dd_dev.dd_desc = &dd->dd_desc[0];
snprintf(dd->dd_drivername, sizeof(dd->dd_drivername), "%s",
udev.dv_drivername);
dd->dd_dev.dd_drivername = &dd->dd_drivername[0];
snprintf(dd->dd_pnpinfo, sizeof(dd->dd_pnpinfo), "%s",
udev.dv_pnpinfo);
dd->dd_dev.dd_pnpinfo = &dd->dd_pnpinfo[0];
snprintf(dd->dd_location, sizeof(dd->dd_location), "%s",
udev.dv_location);
dd->dd_dev.dd_location = &dd->dd_location[0];
dd->dd_dev.dd_devflags = udev.dv_devflags;
dd->dd_dev.dd_flags = udev.dv_flags;
dd->dd_dev.dd_state = udev.dv_state;
TAILQ_INSERT_TAIL(&devinfo_dev, dd, dd_link);
}
debug("fetched %d devices", dev_idx);
return(0);
}
static int
devinfo_init_resources(int generation)
{
struct u_rman urman;
struct devinfo_i_rman *dm;
struct u_resource ures;
struct devinfo_i_res *dr;
int rman_idx, res_idx;
int rman_ptr, res_ptr;
int name2oid[2];
int oid[CTL_MAXNAME + 12];
size_t oidlen, rlen;
char *name, *np, *fmt;
int error, hexmode;
/*
* Find the OID for the rman interface node.
* This is just the usual evil, undocumented sysctl juju.
*/
name2oid[0] = 0;
name2oid[1] = 3;
oidlen = sizeof(oid);
name = "hw.bus.rman";
error = sysctl(name2oid, 2, oid, &oidlen, name, strlen(name));
if (error < 0) {
warnx("can't find hw.bus.rman sysctl node");
return(ENOENT);
}
oidlen /= sizeof(int);
if (oidlen > CTL_MAXNAME) {
warnx("hw.bus.rman oid is too large");
return(EINVAL);
}
oid[oidlen++] = generation;
rman_ptr = oidlen++;
res_ptr = oidlen++;
/*
* Scan resource managers.
*
* Stop after a fairly insane number to avoid death in the case
* of kernel corruption.
*/
for (rman_idx = 0; rman_idx < 255; rman_idx++) {
/*
* Get the resource manager information.
*/
oid[rman_ptr] = rman_idx;
oid[res_ptr] = -1;
rlen = sizeof(urman);
error = sysctl(oid, oidlen, &urman, &rlen, NULL, 0);
if (error < 0) {
if (errno == ENOENT) /* end of list */
break;
if (errno != EINVAL) /* gen count skip, restart */
warn("sysctl hw.bus.rman.%d", rman_idx);
return(errno);
}
if ((dm = malloc(sizeof(*dm))) == NULL)
return(ENOMEM);
dm->dm_rman.dm_handle = urman.rm_handle;
dm->dm_rman.dm_start = urman.rm_start;
dm->dm_rman.dm_size = urman.rm_size;
snprintf(dm->dm_desc, DEVINFO_STRLEN, "%s", urman.rm_descr);
dm->dm_rman.dm_desc = &dm->dm_desc[0];
TAILQ_INSERT_TAIL(&devinfo_rman, dm, dm_link);
/*
* Scan resources on this resource manager.
*
* Stop after a fairly insane number to avoid death in the case
* of kernel corruption.
*/
for (res_idx = 0; res_idx < 1000; res_idx++) {
/*
* Get the resource information.
*/
oid[res_ptr] = res_idx;
rlen = sizeof(ures);
error = sysctl(oid, oidlen, &ures, &rlen, NULL, 0);
if (error < 0) {
if (errno == ENOENT) /* end of list */
break;
if (errno != EINVAL) /* gen count skip */
warn("sysctl hw.bus.rman.%d.%d",
rman_idx, res_idx);
return(errno);
}
if ((dr = malloc(sizeof(*dr))) == NULL)
return(ENOMEM);
dr->dr_res.dr_handle = ures.r_handle;
dr->dr_res.dr_rman = ures.r_parent;
dr->dr_res.dr_device = ures.r_device;
dr->dr_res.dr_start = ures.r_start;
dr->dr_res.dr_size = ures.r_size;
TAILQ_INSERT_TAIL(&devinfo_res, dr, dr_link);
}
debug("fetched %d resources", res_idx);
}
debug("scanned %d resource managers", rman_idx);
return(0);
}
/*
* Free the list contents.
*/
void
devinfo_free(void)
{
struct devinfo_i_dev *dd;
struct devinfo_i_rman *dm;
struct devinfo_i_res *dr;
while ((dd = TAILQ_FIRST(&devinfo_dev)) != NULL) {
TAILQ_REMOVE(&devinfo_dev, dd, dd_link);
free(dd);
}
while ((dm = TAILQ_FIRST(&devinfo_rman)) != NULL) {
TAILQ_REMOVE(&devinfo_rman, dm, dm_link);
free(dm);
}
while ((dr = TAILQ_FIRST(&devinfo_res)) != NULL) {
TAILQ_REMOVE(&devinfo_res, dr, dr_link);
free(dr);
}
devinfo_initted = 0;
}
/*
* Find a device by its handle.
*/
struct devinfo_dev *
devinfo_handle_to_device(devinfo_handle_t handle)
{
struct devinfo_i_dev *dd;
/*
* Find the root device, whose parent is NULL
*/
if (handle == DEVINFO_ROOT_DEVICE) {
TAILQ_FOREACH(dd, &devinfo_dev, dd_link)
if (dd->dd_dev.dd_parent == DEVINFO_ROOT_DEVICE)
return(&dd->dd_dev);
return(NULL);
}
/*
* Scan for the device
*/
TAILQ_FOREACH(dd, &devinfo_dev, dd_link)
if (dd->dd_dev.dd_handle == handle)
return(&dd->dd_dev);
return(NULL);
}
/*
* Find a resource by its handle.
*/
struct devinfo_res *
devinfo_handle_to_resource(devinfo_handle_t handle)
{
struct devinfo_i_res *dr;
TAILQ_FOREACH(dr, &devinfo_res, dr_link)
if (dr->dr_res.dr_handle == handle)
return(&dr->dr_res);
return(NULL);
}
/*
* Find a resource manager by its handle.
*/
struct devinfo_rman *
devinfo_handle_to_rman(devinfo_handle_t handle)
{
struct devinfo_i_rman *dm;
TAILQ_FOREACH(dm, &devinfo_rman, dm_link)
if (dm->dm_rman.dm_handle == handle)
return(&dm->dm_rman);
return(NULL);
}
/*
* Iterate over the children of a device, calling (fn) on each. If
* (fn) returns nonzero, abort the scan and return.
*/
int
devinfo_foreach_device_child(struct devinfo_dev *parent,
int (* fn)(struct devinfo_dev *child, void *arg),
void *arg)
{
struct devinfo_i_dev *dd;
int error;
TAILQ_FOREACH(dd, &devinfo_dev, dd_link)
if (dd->dd_dev.dd_parent == parent->dd_handle)
if ((error = fn(&dd->dd_dev, arg)) != 0)
return(error);
return(0);
}
/*
* Iterate over all the resources owned by a device, calling (fn) on each.
* If (fn) returns nonzero, abort the scan and return.
*/
int
devinfo_foreach_device_resource(struct devinfo_dev *dev,
int (* fn)(struct devinfo_dev *dev, struct devinfo_res *res, void *arg),
void *arg)
{
struct devinfo_i_res *dr;
int error;
TAILQ_FOREACH(dr, &devinfo_res, dr_link)
if (dr->dr_res.dr_device == dev->dd_handle)
if ((error = fn(dev, &dr->dr_res, arg)) != 0)
return(error);
return(0);
}
/*
* Iterate over all the resources owned by a resource manager, calling (fn)
* on each. If (fn) returns nonzero, abort the scan and return.
*/
extern int
devinfo_foreach_rman_resource(struct devinfo_rman *rman,
int (* fn)(struct devinfo_res *res, void *arg),
void *arg)
{
struct devinfo_i_res *dr;
int error;
TAILQ_FOREACH(dr, &devinfo_res, dr_link)
if (dr->dr_res.dr_rman == rman->dm_handle)
if ((error = fn(&dr->dr_res, arg)) != 0)
return(error);
return(0);
}
/*
* Iterate over all the resource managers, calling (fn) on each. If (fn)
* returns nonzero, abort the scan and return.
*/
extern int
devinfo_foreach_rman(int (* fn)(struct devinfo_rman *rman, void *arg),
void *arg)
{
struct devinfo_i_rman *dm;
int error;
TAILQ_FOREACH(dm, &devinfo_rman, dm_link)
if ((error = fn(&dm->dm_rman, arg)) != 0)
return(error);
return(0);
}