linux/net/batman-adv/bat_sysfs.c
Marek Lindner ed75ccbe26 batman-adv: Correct rcu refcounting for batman_if
It might be possible that 2 threads access the same data in the same
rcu grace period. The first thread calls call_rcu() to decrement the
refcount and free the data while the second thread increases the
refcount to use the data. To avoid this race condition all refcount
operations have to be atomic.

Reported-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
2011-03-05 12:50:07 +01:00

591 lines
16 KiB
C

/*
* Copyright (C) 2010-2011 B.A.T.M.A.N. contributors:
*
* Marek Lindner
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA
*
*/
#include "main.h"
#include "bat_sysfs.h"
#include "translation-table.h"
#include "originator.h"
#include "hard-interface.h"
#include "gateway_common.h"
#include "gateway_client.h"
#include "vis.h"
#define to_dev(obj) container_of(obj, struct device, kobj)
#define kobj_to_netdev(obj) to_net_dev(to_dev(obj->parent))
#define kobj_to_batpriv(obj) netdev_priv(kobj_to_netdev(obj))
/* Use this, if you have customized show and store functions */
#define BAT_ATTR(_name, _mode, _show, _store) \
struct bat_attribute bat_attr_##_name = { \
.attr = {.name = __stringify(_name), \
.mode = _mode }, \
.show = _show, \
.store = _store, \
};
#define BAT_ATTR_STORE_BOOL(_name, _post_func) \
ssize_t store_##_name(struct kobject *kobj, struct attribute *attr, \
char *buff, size_t count) \
{ \
struct net_device *net_dev = kobj_to_netdev(kobj); \
struct bat_priv *bat_priv = netdev_priv(net_dev); \
return __store_bool_attr(buff, count, _post_func, attr, \
&bat_priv->_name, net_dev); \
}
#define BAT_ATTR_SHOW_BOOL(_name) \
ssize_t show_##_name(struct kobject *kobj, struct attribute *attr, \
char *buff) \
{ \
struct bat_priv *bat_priv = kobj_to_batpriv(kobj); \
return sprintf(buff, "%s\n", \
atomic_read(&bat_priv->_name) == 0 ? \
"disabled" : "enabled"); \
} \
/* Use this, if you are going to turn a [name] in bat_priv on or off */
#define BAT_ATTR_BOOL(_name, _mode, _post_func) \
static BAT_ATTR_STORE_BOOL(_name, _post_func) \
static BAT_ATTR_SHOW_BOOL(_name) \
static BAT_ATTR(_name, _mode, show_##_name, store_##_name)
#define BAT_ATTR_STORE_UINT(_name, _min, _max, _post_func) \
ssize_t store_##_name(struct kobject *kobj, struct attribute *attr, \
char *buff, size_t count) \
{ \
struct net_device *net_dev = kobj_to_netdev(kobj); \
struct bat_priv *bat_priv = netdev_priv(net_dev); \
return __store_uint_attr(buff, count, _min, _max, _post_func, \
attr, &bat_priv->_name, net_dev); \
}
#define BAT_ATTR_SHOW_UINT(_name) \
ssize_t show_##_name(struct kobject *kobj, struct attribute *attr, \
char *buff) \
{ \
struct bat_priv *bat_priv = kobj_to_batpriv(kobj); \
return sprintf(buff, "%i\n", atomic_read(&bat_priv->_name)); \
} \
/* Use this, if you are going to set [name] in bat_priv to unsigned integer
* values only */
#define BAT_ATTR_UINT(_name, _mode, _min, _max, _post_func) \
static BAT_ATTR_STORE_UINT(_name, _min, _max, _post_func) \
static BAT_ATTR_SHOW_UINT(_name) \
static BAT_ATTR(_name, _mode, show_##_name, store_##_name)
static int store_bool_attr(char *buff, size_t count,
struct net_device *net_dev,
char *attr_name, atomic_t *attr)
{
int enabled = -1;
if (buff[count - 1] == '\n')
buff[count - 1] = '\0';
if ((strncmp(buff, "1", 2) == 0) ||
(strncmp(buff, "enable", 7) == 0) ||
(strncmp(buff, "enabled", 8) == 0))
enabled = 1;
if ((strncmp(buff, "0", 2) == 0) ||
(strncmp(buff, "disable", 8) == 0) ||
(strncmp(buff, "disabled", 9) == 0))
enabled = 0;
if (enabled < 0) {
bat_info(net_dev,
"%s: Invalid parameter received: %s\n",
attr_name, buff);
return -EINVAL;
}
if (atomic_read(attr) == enabled)
return count;
bat_info(net_dev, "%s: Changing from: %s to: %s\n", attr_name,
atomic_read(attr) == 1 ? "enabled" : "disabled",
enabled == 1 ? "enabled" : "disabled");
atomic_set(attr, (unsigned)enabled);
return count;
}
static inline ssize_t __store_bool_attr(char *buff, size_t count,
void (*post_func)(struct net_device *),
struct attribute *attr,
atomic_t *attr_store, struct net_device *net_dev)
{
int ret;
ret = store_bool_attr(buff, count, net_dev, (char *)attr->name,
attr_store);
if (post_func && ret)
post_func(net_dev);
return ret;
}
static int store_uint_attr(char *buff, size_t count,
struct net_device *net_dev, char *attr_name,
unsigned int min, unsigned int max, atomic_t *attr)
{
unsigned long uint_val;
int ret;
ret = strict_strtoul(buff, 10, &uint_val);
if (ret) {
bat_info(net_dev,
"%s: Invalid parameter received: %s\n",
attr_name, buff);
return -EINVAL;
}
if (uint_val < min) {
bat_info(net_dev, "%s: Value is too small: %lu min: %u\n",
attr_name, uint_val, min);
return -EINVAL;
}
if (uint_val > max) {
bat_info(net_dev, "%s: Value is too big: %lu max: %u\n",
attr_name, uint_val, max);
return -EINVAL;
}
if (atomic_read(attr) == uint_val)
return count;
bat_info(net_dev, "%s: Changing from: %i to: %lu\n",
attr_name, atomic_read(attr), uint_val);
atomic_set(attr, uint_val);
return count;
}
static inline ssize_t __store_uint_attr(char *buff, size_t count,
int min, int max,
void (*post_func)(struct net_device *),
struct attribute *attr,
atomic_t *attr_store, struct net_device *net_dev)
{
int ret;
ret = store_uint_attr(buff, count, net_dev, (char *)attr->name,
min, max, attr_store);
if (post_func && ret)
post_func(net_dev);
return ret;
}
static ssize_t show_vis_mode(struct kobject *kobj, struct attribute *attr,
char *buff)
{
struct bat_priv *bat_priv = kobj_to_batpriv(kobj);
int vis_mode = atomic_read(&bat_priv->vis_mode);
return sprintf(buff, "%s\n",
vis_mode == VIS_TYPE_CLIENT_UPDATE ?
"client" : "server");
}
static ssize_t store_vis_mode(struct kobject *kobj, struct attribute *attr,
char *buff, size_t count)
{
struct net_device *net_dev = kobj_to_netdev(kobj);
struct bat_priv *bat_priv = netdev_priv(net_dev);
unsigned long val;
int ret, vis_mode_tmp = -1;
ret = strict_strtoul(buff, 10, &val);
if (((count == 2) && (!ret) && (val == VIS_TYPE_CLIENT_UPDATE)) ||
(strncmp(buff, "client", 6) == 0) ||
(strncmp(buff, "off", 3) == 0))
vis_mode_tmp = VIS_TYPE_CLIENT_UPDATE;
if (((count == 2) && (!ret) && (val == VIS_TYPE_SERVER_SYNC)) ||
(strncmp(buff, "server", 6) == 0))
vis_mode_tmp = VIS_TYPE_SERVER_SYNC;
if (vis_mode_tmp < 0) {
if (buff[count - 1] == '\n')
buff[count - 1] = '\0';
bat_info(net_dev,
"Invalid parameter for 'vis mode' setting received: "
"%s\n", buff);
return -EINVAL;
}
if (atomic_read(&bat_priv->vis_mode) == vis_mode_tmp)
return count;
bat_info(net_dev, "Changing vis mode from: %s to: %s\n",
atomic_read(&bat_priv->vis_mode) == VIS_TYPE_CLIENT_UPDATE ?
"client" : "server", vis_mode_tmp == VIS_TYPE_CLIENT_UPDATE ?
"client" : "server");
atomic_set(&bat_priv->vis_mode, (unsigned)vis_mode_tmp);
return count;
}
static void post_gw_deselect(struct net_device *net_dev)
{
struct bat_priv *bat_priv = netdev_priv(net_dev);
gw_deselect(bat_priv);
}
static ssize_t show_gw_mode(struct kobject *kobj, struct attribute *attr,
char *buff)
{
struct bat_priv *bat_priv = kobj_to_batpriv(kobj);
int bytes_written;
switch (atomic_read(&bat_priv->gw_mode)) {
case GW_MODE_CLIENT:
bytes_written = sprintf(buff, "%s\n", GW_MODE_CLIENT_NAME);
break;
case GW_MODE_SERVER:
bytes_written = sprintf(buff, "%s\n", GW_MODE_SERVER_NAME);
break;
default:
bytes_written = sprintf(buff, "%s\n", GW_MODE_OFF_NAME);
break;
}
return bytes_written;
}
static ssize_t store_gw_mode(struct kobject *kobj, struct attribute *attr,
char *buff, size_t count)
{
struct net_device *net_dev = kobj_to_netdev(kobj);
struct bat_priv *bat_priv = netdev_priv(net_dev);
char *curr_gw_mode_str;
int gw_mode_tmp = -1;
if (buff[count - 1] == '\n')
buff[count - 1] = '\0';
if (strncmp(buff, GW_MODE_OFF_NAME, strlen(GW_MODE_OFF_NAME)) == 0)
gw_mode_tmp = GW_MODE_OFF;
if (strncmp(buff, GW_MODE_CLIENT_NAME,
strlen(GW_MODE_CLIENT_NAME)) == 0)
gw_mode_tmp = GW_MODE_CLIENT;
if (strncmp(buff, GW_MODE_SERVER_NAME,
strlen(GW_MODE_SERVER_NAME)) == 0)
gw_mode_tmp = GW_MODE_SERVER;
if (gw_mode_tmp < 0) {
bat_info(net_dev,
"Invalid parameter for 'gw mode' setting received: "
"%s\n", buff);
return -EINVAL;
}
if (atomic_read(&bat_priv->gw_mode) == gw_mode_tmp)
return count;
switch (atomic_read(&bat_priv->gw_mode)) {
case GW_MODE_CLIENT:
curr_gw_mode_str = GW_MODE_CLIENT_NAME;
break;
case GW_MODE_SERVER:
curr_gw_mode_str = GW_MODE_SERVER_NAME;
break;
default:
curr_gw_mode_str = GW_MODE_OFF_NAME;
break;
}
bat_info(net_dev, "Changing gw mode from: %s to: %s\n",
curr_gw_mode_str, buff);
gw_deselect(bat_priv);
atomic_set(&bat_priv->gw_mode, (unsigned)gw_mode_tmp);
return count;
}
static ssize_t show_gw_bwidth(struct kobject *kobj, struct attribute *attr,
char *buff)
{
struct bat_priv *bat_priv = kobj_to_batpriv(kobj);
int down, up;
int gw_bandwidth = atomic_read(&bat_priv->gw_bandwidth);
gw_bandwidth_to_kbit(gw_bandwidth, &down, &up);
return sprintf(buff, "%i%s/%i%s\n",
(down > 2048 ? down / 1024 : down),
(down > 2048 ? "MBit" : "KBit"),
(up > 2048 ? up / 1024 : up),
(up > 2048 ? "MBit" : "KBit"));
}
static ssize_t store_gw_bwidth(struct kobject *kobj, struct attribute *attr,
char *buff, size_t count)
{
struct net_device *net_dev = kobj_to_netdev(kobj);
if (buff[count - 1] == '\n')
buff[count - 1] = '\0';
return gw_bandwidth_set(net_dev, buff, count);
}
BAT_ATTR_BOOL(aggregated_ogms, S_IRUGO | S_IWUSR, NULL);
BAT_ATTR_BOOL(bonding, S_IRUGO | S_IWUSR, NULL);
BAT_ATTR_BOOL(fragmentation, S_IRUGO | S_IWUSR, update_min_mtu);
static BAT_ATTR(vis_mode, S_IRUGO | S_IWUSR, show_vis_mode, store_vis_mode);
static BAT_ATTR(gw_mode, S_IRUGO | S_IWUSR, show_gw_mode, store_gw_mode);
BAT_ATTR_UINT(orig_interval, S_IRUGO | S_IWUSR, 2 * JITTER, INT_MAX, NULL);
BAT_ATTR_UINT(hop_penalty, S_IRUGO | S_IWUSR, 0, TQ_MAX_VALUE, NULL);
BAT_ATTR_UINT(gw_sel_class, S_IRUGO | S_IWUSR, 1, TQ_MAX_VALUE,
post_gw_deselect);
static BAT_ATTR(gw_bandwidth, S_IRUGO | S_IWUSR, show_gw_bwidth,
store_gw_bwidth);
#ifdef CONFIG_BATMAN_ADV_DEBUG
BAT_ATTR_UINT(log_level, S_IRUGO | S_IWUSR, 0, 3, NULL);
#endif
static struct bat_attribute *mesh_attrs[] = {
&bat_attr_aggregated_ogms,
&bat_attr_bonding,
&bat_attr_fragmentation,
&bat_attr_vis_mode,
&bat_attr_gw_mode,
&bat_attr_orig_interval,
&bat_attr_hop_penalty,
&bat_attr_gw_sel_class,
&bat_attr_gw_bandwidth,
#ifdef CONFIG_BATMAN_ADV_DEBUG
&bat_attr_log_level,
#endif
NULL,
};
int sysfs_add_meshif(struct net_device *dev)
{
struct kobject *batif_kobject = &dev->dev.kobj;
struct bat_priv *bat_priv = netdev_priv(dev);
struct bat_attribute **bat_attr;
int err;
bat_priv->mesh_obj = kobject_create_and_add(SYSFS_IF_MESH_SUBDIR,
batif_kobject);
if (!bat_priv->mesh_obj) {
bat_err(dev, "Can't add sysfs directory: %s/%s\n", dev->name,
SYSFS_IF_MESH_SUBDIR);
goto out;
}
for (bat_attr = mesh_attrs; *bat_attr; ++bat_attr) {
err = sysfs_create_file(bat_priv->mesh_obj,
&((*bat_attr)->attr));
if (err) {
bat_err(dev, "Can't add sysfs file: %s/%s/%s\n",
dev->name, SYSFS_IF_MESH_SUBDIR,
((*bat_attr)->attr).name);
goto rem_attr;
}
}
return 0;
rem_attr:
for (bat_attr = mesh_attrs; *bat_attr; ++bat_attr)
sysfs_remove_file(bat_priv->mesh_obj, &((*bat_attr)->attr));
kobject_put(bat_priv->mesh_obj);
bat_priv->mesh_obj = NULL;
out:
return -ENOMEM;
}
void sysfs_del_meshif(struct net_device *dev)
{
struct bat_priv *bat_priv = netdev_priv(dev);
struct bat_attribute **bat_attr;
for (bat_attr = mesh_attrs; *bat_attr; ++bat_attr)
sysfs_remove_file(bat_priv->mesh_obj, &((*bat_attr)->attr));
kobject_put(bat_priv->mesh_obj);
bat_priv->mesh_obj = NULL;
}
static ssize_t show_mesh_iface(struct kobject *kobj, struct attribute *attr,
char *buff)
{
struct net_device *net_dev = kobj_to_netdev(kobj);
struct batman_if *batman_if = get_batman_if_by_netdev(net_dev);
ssize_t length;
if (!batman_if)
return 0;
length = sprintf(buff, "%s\n", batman_if->if_status == IF_NOT_IN_USE ?
"none" : batman_if->soft_iface->name);
hardif_free_ref(batman_if);
return length;
}
static ssize_t store_mesh_iface(struct kobject *kobj, struct attribute *attr,
char *buff, size_t count)
{
struct net_device *net_dev = kobj_to_netdev(kobj);
struct batman_if *batman_if = get_batman_if_by_netdev(net_dev);
int status_tmp = -1;
int ret = count;
if (!batman_if)
return count;
if (buff[count - 1] == '\n')
buff[count - 1] = '\0';
if (strlen(buff) >= IFNAMSIZ) {
pr_err("Invalid parameter for 'mesh_iface' setting received: "
"interface name too long '%s'\n", buff);
hardif_free_ref(batman_if);
return -EINVAL;
}
if (strncmp(buff, "none", 4) == 0)
status_tmp = IF_NOT_IN_USE;
else
status_tmp = IF_I_WANT_YOU;
if ((batman_if->if_status == status_tmp) || ((batman_if->soft_iface) &&
(strncmp(batman_if->soft_iface->name, buff, IFNAMSIZ) == 0)))
goto out;
if (status_tmp == IF_NOT_IN_USE) {
rtnl_lock();
hardif_disable_interface(batman_if);
rtnl_unlock();
goto out;
}
/* if the interface already is in use */
if (batman_if->if_status != IF_NOT_IN_USE) {
rtnl_lock();
hardif_disable_interface(batman_if);
rtnl_unlock();
}
ret = hardif_enable_interface(batman_if, buff);
out:
hardif_free_ref(batman_if);
return ret;
}
static ssize_t show_iface_status(struct kobject *kobj, struct attribute *attr,
char *buff)
{
struct net_device *net_dev = kobj_to_netdev(kobj);
struct batman_if *batman_if = get_batman_if_by_netdev(net_dev);
ssize_t length;
if (!batman_if)
return 0;
switch (batman_if->if_status) {
case IF_TO_BE_REMOVED:
length = sprintf(buff, "disabling\n");
break;
case IF_INACTIVE:
length = sprintf(buff, "inactive\n");
break;
case IF_ACTIVE:
length = sprintf(buff, "active\n");
break;
case IF_TO_BE_ACTIVATED:
length = sprintf(buff, "enabling\n");
break;
case IF_NOT_IN_USE:
default:
length = sprintf(buff, "not in use\n");
break;
}
hardif_free_ref(batman_if);
return length;
}
static BAT_ATTR(mesh_iface, S_IRUGO | S_IWUSR,
show_mesh_iface, store_mesh_iface);
static BAT_ATTR(iface_status, S_IRUGO, show_iface_status, NULL);
static struct bat_attribute *batman_attrs[] = {
&bat_attr_mesh_iface,
&bat_attr_iface_status,
NULL,
};
int sysfs_add_hardif(struct kobject **hardif_obj, struct net_device *dev)
{
struct kobject *hardif_kobject = &dev->dev.kobj;
struct bat_attribute **bat_attr;
int err;
*hardif_obj = kobject_create_and_add(SYSFS_IF_BAT_SUBDIR,
hardif_kobject);
if (!*hardif_obj) {
bat_err(dev, "Can't add sysfs directory: %s/%s\n", dev->name,
SYSFS_IF_BAT_SUBDIR);
goto out;
}
for (bat_attr = batman_attrs; *bat_attr; ++bat_attr) {
err = sysfs_create_file(*hardif_obj, &((*bat_attr)->attr));
if (err) {
bat_err(dev, "Can't add sysfs file: %s/%s/%s\n",
dev->name, SYSFS_IF_BAT_SUBDIR,
((*bat_attr)->attr).name);
goto rem_attr;
}
}
return 0;
rem_attr:
for (bat_attr = batman_attrs; *bat_attr; ++bat_attr)
sysfs_remove_file(*hardif_obj, &((*bat_attr)->attr));
out:
return -ENOMEM;
}
void sysfs_del_hardif(struct kobject **hardif_obj)
{
kobject_put(*hardif_obj);
*hardif_obj = NULL;
}