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linux/drivers/net/bonding/bond_sysfs.c
Ben Hutchings ad246c992b ipv4, ipv6, bonding: Restore control over number of peer notifications 
For backward compatibility, we should retain the module parameters and
sysfs attributes to control the number of peer notifications
(gratuitous ARPs and unsolicited NAs) sent after bonding failover.
Also, it is possible for failover to take place even though the new
active slave does not have link up, and in that case the peer
notification should be deferred until it does.

Change ipv4 and ipv6 so they do not automatically send peer
notifications on bonding failover.

Change the bonding driver to send separate NETDEV_NOTIFY_PEERS
notifications when the link is up, as many times as requested.  Since
it does not directly control which protocols send notifications, make
num_grat_arp and num_unsol_na aliases for a single parameter.  Bump
the bonding version number and update its documentation.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Acked-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-04-29 12:44:11 -07:00

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/*
* Copyright(c) 2004-2005 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* 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.,
* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* The full GNU General Public License is included in this distribution in the
* file called LICENSE.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/sched.h>
#include <linux/sysdev.h>
#include <linux/fs.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/netdevice.h>
#include <linux/inetdevice.h>
#include <linux/in.h>
#include <linux/sysfs.h>
#include <linux/ctype.h>
#include <linux/inet.h>
#include <linux/rtnetlink.h>
#include <linux/etherdevice.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include <linux/nsproxy.h>
#include "bonding.h"
#define to_dev(obj) container_of(obj, struct device, kobj)
#define to_bond(cd) ((struct bonding *)(netdev_priv(to_net_dev(cd))))
/*
* "show" function for the bond_masters attribute.
* The class parameter is ignored.
*/
static ssize_t bonding_show_bonds(struct class *cls,
struct class_attribute *attr,
char *buf)
{
struct net *net = current->nsproxy->net_ns;
struct bond_net *bn = net_generic(net, bond_net_id);
int res = 0;
struct bonding *bond;
rtnl_lock();
list_for_each_entry(bond, &bn->dev_list, bond_list) {
if (res > (PAGE_SIZE - IFNAMSIZ)) {
/* not enough space for another interface name */
if ((PAGE_SIZE - res) > 10)
res = PAGE_SIZE - 10;
res += sprintf(buf + res, "++more++ ");
break;
}
res += sprintf(buf + res, "%s ", bond->dev->name);
}
if (res)
buf[res-1] = '\n'; /* eat the leftover space */
rtnl_unlock();
return res;
}
static struct net_device *bond_get_by_name(struct net *net, const char *ifname)
{
struct bond_net *bn = net_generic(net, bond_net_id);
struct bonding *bond;
list_for_each_entry(bond, &bn->dev_list, bond_list) {
if (strncmp(bond->dev->name, ifname, IFNAMSIZ) == 0)
return bond->dev;
}
return NULL;
}
/*
* "store" function for the bond_masters attribute. This is what
* creates and deletes entire bonds.
*
* The class parameter is ignored.
*
*/
static ssize_t bonding_store_bonds(struct class *cls,
struct class_attribute *attr,
const char *buffer, size_t count)
{
struct net *net = current->nsproxy->net_ns;
char command[IFNAMSIZ + 1] = {0, };
char *ifname;
int rv, res = count;
sscanf(buffer, "%16s", command); /* IFNAMSIZ*/
ifname = command + 1;
if ((strlen(command) <= 1) ||
!dev_valid_name(ifname))
goto err_no_cmd;
if (command[0] == '+') {
pr_info("%s is being created...\n", ifname);
rv = bond_create(net, ifname);
if (rv) {
if (rv == -EEXIST)
pr_info("%s already exists.\n", ifname);
else
pr_info("%s creation failed.\n", ifname);
res = rv;
}
} else if (command[0] == '-') {
struct net_device *bond_dev;
rtnl_lock();
bond_dev = bond_get_by_name(net, ifname);
if (bond_dev) {
pr_info("%s is being deleted...\n", ifname);
unregister_netdevice(bond_dev);
} else {
pr_err("unable to delete non-existent %s\n", ifname);
res = -ENODEV;
}
rtnl_unlock();
} else
goto err_no_cmd;
/* Always return either count or an error. If you return 0, you'll
* get called forever, which is bad.
*/
return res;
err_no_cmd:
pr_err("no command found in bonding_masters. Use +ifname or -ifname.\n");
return -EPERM;
}
/* class attribute for bond_masters file. This ends up in /sys/class/net */
static CLASS_ATTR(bonding_masters, S_IWUSR | S_IRUGO,
bonding_show_bonds, bonding_store_bonds);
int bond_create_slave_symlinks(struct net_device *master,
struct net_device *slave)
{
char linkname[IFNAMSIZ+7];
int ret = 0;
/* first, create a link from the slave back to the master */
ret = sysfs_create_link(&(slave->dev.kobj), &(master->dev.kobj),
"master");
if (ret)
return ret;
/* next, create a link from the master to the slave */
sprintf(linkname, "slave_%s", slave->name);
ret = sysfs_create_link(&(master->dev.kobj), &(slave->dev.kobj),
linkname);
return ret;
}
void bond_destroy_slave_symlinks(struct net_device *master,
struct net_device *slave)
{
char linkname[IFNAMSIZ+7];
sysfs_remove_link(&(slave->dev.kobj), "master");
sprintf(linkname, "slave_%s", slave->name);
sysfs_remove_link(&(master->dev.kobj), linkname);
}
/*
* Show the slaves in the current bond.
*/
static ssize_t bonding_show_slaves(struct device *d,
struct device_attribute *attr, char *buf)
{
struct slave *slave;
int i, res = 0;
struct bonding *bond = to_bond(d);
read_lock(&bond->lock);
bond_for_each_slave(bond, slave, i) {
if (res > (PAGE_SIZE - IFNAMSIZ)) {
/* not enough space for another interface name */
if ((PAGE_SIZE - res) > 10)
res = PAGE_SIZE - 10;
res += sprintf(buf + res, "++more++ ");
break;
}
res += sprintf(buf + res, "%s ", slave->dev->name);
}
read_unlock(&bond->lock);
if (res)
buf[res-1] = '\n'; /* eat the leftover space */
return res;
}
/*
* Set the slaves in the current bond. The bond interface must be
* up for this to succeed.
* This is supposed to be only thin wrapper for bond_enslave and bond_release.
* All hard work should be done there.
*/
static ssize_t bonding_store_slaves(struct device *d,
struct device_attribute *attr,
const char *buffer, size_t count)
{
char command[IFNAMSIZ + 1] = { 0, };
char *ifname;
int res, ret = count;
struct net_device *dev;
struct bonding *bond = to_bond(d);
/* Quick sanity check -- is the bond interface up? */
if (!(bond->dev->flags & IFF_UP)) {
pr_warning("%s: doing slave updates when interface is down.\n",
bond->dev->name);
}
if (!rtnl_trylock())
return restart_syscall();
sscanf(buffer, "%16s", command); /* IFNAMSIZ*/
ifname = command + 1;
if ((strlen(command) <= 1) ||
!dev_valid_name(ifname))
goto err_no_cmd;
dev = __dev_get_by_name(dev_net(bond->dev), ifname);
if (!dev) {
pr_info("%s: Interface %s does not exist!\n",
bond->dev->name, ifname);
ret = -ENODEV;
goto out;
}
switch (command[0]) {
case '+':
pr_info("%s: Adding slave %s.\n", bond->dev->name, dev->name);
res = bond_enslave(bond->dev, dev);
break;
case '-':
pr_info("%s: Removing slave %s.\n", bond->dev->name, dev->name);
res = bond_release(bond->dev, dev);
break;
default:
goto err_no_cmd;
}
if (res)
ret = res;
goto out;
err_no_cmd:
pr_err("no command found in slaves file for bond %s. Use +ifname or -ifname.\n",
bond->dev->name);
ret = -EPERM;
out:
rtnl_unlock();
return ret;
}
static DEVICE_ATTR(slaves, S_IRUGO | S_IWUSR, bonding_show_slaves,
bonding_store_slaves);
/*
* Show and set the bonding mode. The bond interface must be down to
* change the mode.
*/
static ssize_t bonding_show_mode(struct device *d,
struct device_attribute *attr, char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%s %d\n",
bond_mode_tbl[bond->params.mode].modename,
bond->params.mode);
}
static ssize_t bonding_store_mode(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (bond->dev->flags & IFF_UP) {
pr_err("unable to update mode of %s because interface is up.\n",
bond->dev->name);
ret = -EPERM;
goto out;
}
new_value = bond_parse_parm(buf, bond_mode_tbl);
if (new_value < 0) {
pr_err("%s: Ignoring invalid mode value %.*s.\n",
bond->dev->name, (int)strlen(buf) - 1, buf);
ret = -EINVAL;
goto out;
}
if ((new_value == BOND_MODE_ALB ||
new_value == BOND_MODE_TLB) &&
bond->params.arp_interval) {
pr_err("%s: %s mode is incompatible with arp monitoring.\n",
bond->dev->name, bond_mode_tbl[new_value].modename);
ret = -EINVAL;
goto out;
}
bond->params.mode = new_value;
bond_set_mode_ops(bond, bond->params.mode);
pr_info("%s: setting mode to %s (%d).\n",
bond->dev->name, bond_mode_tbl[new_value].modename,
new_value);
out:
return ret;
}
static DEVICE_ATTR(mode, S_IRUGO | S_IWUSR,
bonding_show_mode, bonding_store_mode);
/*
* Show and set the bonding transmit hash method.
* The bond interface must be down to change the xmit hash policy.
*/
static ssize_t bonding_show_xmit_hash(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%s %d\n",
xmit_hashtype_tbl[bond->params.xmit_policy].modename,
bond->params.xmit_policy);
}
static ssize_t bonding_store_xmit_hash(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (bond->dev->flags & IFF_UP) {
pr_err("%s: Interface is up. Unable to update xmit policy.\n",
bond->dev->name);
ret = -EPERM;
goto out;
}
new_value = bond_parse_parm(buf, xmit_hashtype_tbl);
if (new_value < 0) {
pr_err("%s: Ignoring invalid xmit hash policy value %.*s.\n",
bond->dev->name,
(int)strlen(buf) - 1, buf);
ret = -EINVAL;
goto out;
} else {
bond->params.xmit_policy = new_value;
bond_set_mode_ops(bond, bond->params.mode);
pr_info("%s: setting xmit hash policy to %s (%d).\n",
bond->dev->name,
xmit_hashtype_tbl[new_value].modename, new_value);
}
out:
return ret;
}
static DEVICE_ATTR(xmit_hash_policy, S_IRUGO | S_IWUSR,
bonding_show_xmit_hash, bonding_store_xmit_hash);
/*
* Show and set arp_validate.
*/
static ssize_t bonding_show_arp_validate(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%s %d\n",
arp_validate_tbl[bond->params.arp_validate].modename,
bond->params.arp_validate);
}
static ssize_t bonding_store_arp_validate(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value;
struct bonding *bond = to_bond(d);
new_value = bond_parse_parm(buf, arp_validate_tbl);
if (new_value < 0) {
pr_err("%s: Ignoring invalid arp_validate value %s\n",
bond->dev->name, buf);
return -EINVAL;
}
if (new_value && (bond->params.mode != BOND_MODE_ACTIVEBACKUP)) {
pr_err("%s: arp_validate only supported in active-backup mode.\n",
bond->dev->name);
return -EINVAL;
}
pr_info("%s: setting arp_validate to %s (%d).\n",
bond->dev->name, arp_validate_tbl[new_value].modename,
new_value);
bond->params.arp_validate = new_value;
return count;
}
static DEVICE_ATTR(arp_validate, S_IRUGO | S_IWUSR, bonding_show_arp_validate,
bonding_store_arp_validate);
/*
* Show and store fail_over_mac. User only allowed to change the
* value when there are no slaves.
*/
static ssize_t bonding_show_fail_over_mac(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%s %d\n",
fail_over_mac_tbl[bond->params.fail_over_mac].modename,
bond->params.fail_over_mac);
}
static ssize_t bonding_store_fail_over_mac(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value;
struct bonding *bond = to_bond(d);
if (bond->slave_cnt != 0) {
pr_err("%s: Can't alter fail_over_mac with slaves in bond.\n",
bond->dev->name);
return -EPERM;
}
new_value = bond_parse_parm(buf, fail_over_mac_tbl);
if (new_value < 0) {
pr_err("%s: Ignoring invalid fail_over_mac value %s.\n",
bond->dev->name, buf);
return -EINVAL;
}
bond->params.fail_over_mac = new_value;
pr_info("%s: Setting fail_over_mac to %s (%d).\n",
bond->dev->name, fail_over_mac_tbl[new_value].modename,
new_value);
return count;
}
static DEVICE_ATTR(fail_over_mac, S_IRUGO | S_IWUSR,
bonding_show_fail_over_mac, bonding_store_fail_over_mac);
/*
* Show and set the arp timer interval. There are two tricky bits
* here. First, if ARP monitoring is activated, then we must disable
* MII monitoring. Second, if the ARP timer isn't running, we must
* start it.
*/
static ssize_t bonding_show_arp_interval(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%d\n", bond->params.arp_interval);
}
static ssize_t bonding_store_arp_interval(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (sscanf(buf, "%d", &new_value) != 1) {
pr_err("%s: no arp_interval value specified.\n",
bond->dev->name);
ret = -EINVAL;
goto out;
}
if (new_value < 0) {
pr_err("%s: Invalid arp_interval value %d not in range 1-%d; rejected.\n",
bond->dev->name, new_value, INT_MAX);
ret = -EINVAL;
goto out;
}
if (bond->params.mode == BOND_MODE_ALB ||
bond->params.mode == BOND_MODE_TLB) {
pr_info("%s: ARP monitoring cannot be used with ALB/TLB. Only MII monitoring is supported on %s.\n",
bond->dev->name, bond->dev->name);
ret = -EINVAL;
goto out;
}
pr_info("%s: Setting ARP monitoring interval to %d.\n",
bond->dev->name, new_value);
bond->params.arp_interval = new_value;
if (bond->params.miimon) {
pr_info("%s: ARP monitoring cannot be used with MII monitoring. %s Disabling MII monitoring.\n",
bond->dev->name, bond->dev->name);
bond->params.miimon = 0;
if (delayed_work_pending(&bond->mii_work)) {
cancel_delayed_work(&bond->mii_work);
flush_workqueue(bond->wq);
}
}
if (!bond->params.arp_targets[0]) {
pr_info("%s: ARP monitoring has been set up, but no ARP targets have been specified.\n",
bond->dev->name);
}
if (bond->dev->flags & IFF_UP) {
/* If the interface is up, we may need to fire off
* the ARP timer. If the interface is down, the
* timer will get fired off when the open function
* is called.
*/
if (!delayed_work_pending(&bond->arp_work)) {
if (bond->params.mode == BOND_MODE_ACTIVEBACKUP)
INIT_DELAYED_WORK(&bond->arp_work,
bond_activebackup_arp_mon);
else
INIT_DELAYED_WORK(&bond->arp_work,
bond_loadbalance_arp_mon);
queue_delayed_work(bond->wq, &bond->arp_work, 0);
}
}
out:
return ret;
}
static DEVICE_ATTR(arp_interval, S_IRUGO | S_IWUSR,
bonding_show_arp_interval, bonding_store_arp_interval);
/*
* Show and set the arp targets.
*/
static ssize_t bonding_show_arp_targets(struct device *d,
struct device_attribute *attr,
char *buf)
{
int i, res = 0;
struct bonding *bond = to_bond(d);
for (i = 0; i < BOND_MAX_ARP_TARGETS; i++) {
if (bond->params.arp_targets[i])
res += sprintf(buf + res, "%pI4 ",
&bond->params.arp_targets[i]);
}
if (res)
buf[res-1] = '\n'; /* eat the leftover space */
return res;
}
static ssize_t bonding_store_arp_targets(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
__be32 newtarget;
int i = 0, done = 0, ret = count;
struct bonding *bond = to_bond(d);
__be32 *targets;
targets = bond->params.arp_targets;
newtarget = in_aton(buf + 1);
/* look for adds */
if (buf[0] == '+') {
if ((newtarget == 0) || (newtarget == htonl(INADDR_BROADCAST))) {
pr_err("%s: invalid ARP target %pI4 specified for addition\n",
bond->dev->name, &newtarget);
ret = -EINVAL;
goto out;
}
/* look for an empty slot to put the target in, and check for dupes */
for (i = 0; (i < BOND_MAX_ARP_TARGETS) && !done; i++) {
if (targets[i] == newtarget) { /* duplicate */
pr_err("%s: ARP target %pI4 is already present\n",
bond->dev->name, &newtarget);
ret = -EINVAL;
goto out;
}
if (targets[i] == 0) {
pr_info("%s: adding ARP target %pI4.\n",
bond->dev->name, &newtarget);
done = 1;
targets[i] = newtarget;
}
}
if (!done) {
pr_err("%s: ARP target table is full!\n",
bond->dev->name);
ret = -EINVAL;
goto out;
}
} else if (buf[0] == '-') {
if ((newtarget == 0) || (newtarget == htonl(INADDR_BROADCAST))) {
pr_err("%s: invalid ARP target %pI4 specified for removal\n",
bond->dev->name, &newtarget);
ret = -EINVAL;
goto out;
}
for (i = 0; (i < BOND_MAX_ARP_TARGETS) && !done; i++) {
if (targets[i] == newtarget) {
int j;
pr_info("%s: removing ARP target %pI4.\n",
bond->dev->name, &newtarget);
for (j = i; (j < (BOND_MAX_ARP_TARGETS-1)) && targets[j+1]; j++)
targets[j] = targets[j+1];
targets[j] = 0;
done = 1;
}
}
if (!done) {
pr_info("%s: unable to remove nonexistent ARP target %pI4.\n",
bond->dev->name, &newtarget);
ret = -EINVAL;
goto out;
}
} else {
pr_err("no command found in arp_ip_targets file for bond %s. Use +<addr> or -<addr>.\n",
bond->dev->name);
ret = -EPERM;
goto out;
}
out:
return ret;
}
static DEVICE_ATTR(arp_ip_target, S_IRUGO | S_IWUSR , bonding_show_arp_targets, bonding_store_arp_targets);
/*
* Show and set the up and down delays. These must be multiples of the
* MII monitoring value, and are stored internally as the multiplier.
* Thus, we must translate to MS for the real world.
*/
static ssize_t bonding_show_downdelay(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%d\n", bond->params.downdelay * bond->params.miimon);
}
static ssize_t bonding_store_downdelay(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (!(bond->params.miimon)) {
pr_err("%s: Unable to set down delay as MII monitoring is disabled\n",
bond->dev->name);
ret = -EPERM;
goto out;
}
if (sscanf(buf, "%d", &new_value) != 1) {
pr_err("%s: no down delay value specified.\n", bond->dev->name);
ret = -EINVAL;
goto out;
}
if (new_value < 0) {
pr_err("%s: Invalid down delay value %d not in range %d-%d; rejected.\n",
bond->dev->name, new_value, 1, INT_MAX);
ret = -EINVAL;
goto out;
} else {
if ((new_value % bond->params.miimon) != 0) {
pr_warning("%s: Warning: down delay (%d) is not a multiple of miimon (%d), delay rounded to %d ms\n",
bond->dev->name, new_value,
bond->params.miimon,
(new_value / bond->params.miimon) *
bond->params.miimon);
}
bond->params.downdelay = new_value / bond->params.miimon;
pr_info("%s: Setting down delay to %d.\n",
bond->dev->name,
bond->params.downdelay * bond->params.miimon);
}
out:
return ret;
}
static DEVICE_ATTR(downdelay, S_IRUGO | S_IWUSR,
bonding_show_downdelay, bonding_store_downdelay);
static ssize_t bonding_show_updelay(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%d\n", bond->params.updelay * bond->params.miimon);
}
static ssize_t bonding_store_updelay(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (!(bond->params.miimon)) {
pr_err("%s: Unable to set up delay as MII monitoring is disabled\n",
bond->dev->name);
ret = -EPERM;
goto out;
}
if (sscanf(buf, "%d", &new_value) != 1) {
pr_err("%s: no up delay value specified.\n",
bond->dev->name);
ret = -EINVAL;
goto out;
}
if (new_value < 0) {
pr_err("%s: Invalid down delay value %d not in range %d-%d; rejected.\n",
bond->dev->name, new_value, 1, INT_MAX);
ret = -EINVAL;
goto out;
} else {
if ((new_value % bond->params.miimon) != 0) {
pr_warning("%s: Warning: up delay (%d) is not a multiple of miimon (%d), updelay rounded to %d ms\n",
bond->dev->name, new_value,
bond->params.miimon,
(new_value / bond->params.miimon) *
bond->params.miimon);
}
bond->params.updelay = new_value / bond->params.miimon;
pr_info("%s: Setting up delay to %d.\n",
bond->dev->name,
bond->params.updelay * bond->params.miimon);
}
out:
return ret;
}
static DEVICE_ATTR(updelay, S_IRUGO | S_IWUSR,
bonding_show_updelay, bonding_store_updelay);
/*
* Show and set the LACP interval. Interface must be down, and the mode
* must be set to 802.3ad mode.
*/
static ssize_t bonding_show_lacp(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%s %d\n",
bond_lacp_tbl[bond->params.lacp_fast].modename,
bond->params.lacp_fast);
}
static ssize_t bonding_store_lacp(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (bond->dev->flags & IFF_UP) {
pr_err("%s: Unable to update LACP rate because interface is up.\n",
bond->dev->name);
ret = -EPERM;
goto out;
}
if (bond->params.mode != BOND_MODE_8023AD) {
pr_err("%s: Unable to update LACP rate because bond is not in 802.3ad mode.\n",
bond->dev->name);
ret = -EPERM;
goto out;
}
new_value = bond_parse_parm(buf, bond_lacp_tbl);
if ((new_value == 1) || (new_value == 0)) {
bond->params.lacp_fast = new_value;
pr_info("%s: Setting LACP rate to %s (%d).\n",
bond->dev->name, bond_lacp_tbl[new_value].modename,
new_value);
} else {
pr_err("%s: Ignoring invalid LACP rate value %.*s.\n",
bond->dev->name, (int)strlen(buf) - 1, buf);
ret = -EINVAL;
}
out:
return ret;
}
static DEVICE_ATTR(lacp_rate, S_IRUGO | S_IWUSR,
bonding_show_lacp, bonding_store_lacp);
static ssize_t bonding_show_ad_select(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%s %d\n",
ad_select_tbl[bond->params.ad_select].modename,
bond->params.ad_select);
}
static ssize_t bonding_store_ad_select(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (bond->dev->flags & IFF_UP) {
pr_err("%s: Unable to update ad_select because interface is up.\n",
bond->dev->name);
ret = -EPERM;
goto out;
}
new_value = bond_parse_parm(buf, ad_select_tbl);
if (new_value != -1) {
bond->params.ad_select = new_value;
pr_info("%s: Setting ad_select to %s (%d).\n",
bond->dev->name, ad_select_tbl[new_value].modename,
new_value);
} else {
pr_err("%s: Ignoring invalid ad_select value %.*s.\n",
bond->dev->name, (int)strlen(buf) - 1, buf);
ret = -EINVAL;
}
out:
return ret;
}
static DEVICE_ATTR(ad_select, S_IRUGO | S_IWUSR,
bonding_show_ad_select, bonding_store_ad_select);
/*
* Show and set the number of peer notifications to send after a failover event.
*/
static ssize_t bonding_show_num_peer_notif(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%d\n", bond->params.num_peer_notif);
}
static ssize_t bonding_store_num_peer_notif(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct bonding *bond = to_bond(d);
int err = kstrtou8(buf, 10, &bond->params.num_peer_notif);
return err ? err : count;
}
static DEVICE_ATTR(num_grat_arp, S_IRUGO | S_IWUSR,
bonding_show_num_peer_notif, bonding_store_num_peer_notif);
static DEVICE_ATTR(num_unsol_na, S_IRUGO | S_IWUSR,
bonding_show_num_peer_notif, bonding_store_num_peer_notif);
/*
* Show and set the MII monitor interval. There are two tricky bits
* here. First, if MII monitoring is activated, then we must disable
* ARP monitoring. Second, if the timer isn't running, we must
* start it.
*/
static ssize_t bonding_show_miimon(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%d\n", bond->params.miimon);
}
static ssize_t bonding_store_miimon(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (sscanf(buf, "%d", &new_value) != 1) {
pr_err("%s: no miimon value specified.\n",
bond->dev->name);
ret = -EINVAL;
goto out;
}
if (new_value < 0) {
pr_err("%s: Invalid miimon value %d not in range %d-%d; rejected.\n",
bond->dev->name, new_value, 1, INT_MAX);
ret = -EINVAL;
goto out;
} else {
pr_info("%s: Setting MII monitoring interval to %d.\n",
bond->dev->name, new_value);
bond->params.miimon = new_value;
if (bond->params.updelay)
pr_info("%s: Note: Updating updelay (to %d) since it is a multiple of the miimon value.\n",
bond->dev->name,
bond->params.updelay * bond->params.miimon);
if (bond->params.downdelay)
pr_info("%s: Note: Updating downdelay (to %d) since it is a multiple of the miimon value.\n",
bond->dev->name,
bond->params.downdelay * bond->params.miimon);
if (bond->params.arp_interval) {
pr_info("%s: MII monitoring cannot be used with ARP monitoring. Disabling ARP monitoring...\n",
bond->dev->name);
bond->params.arp_interval = 0;
if (bond->params.arp_validate) {
bond->params.arp_validate =
BOND_ARP_VALIDATE_NONE;
}
if (delayed_work_pending(&bond->arp_work)) {
cancel_delayed_work(&bond->arp_work);
flush_workqueue(bond->wq);
}
}
if (bond->dev->flags & IFF_UP) {
/* If the interface is up, we may need to fire off
* the MII timer. If the interface is down, the
* timer will get fired off when the open function
* is called.
*/
if (!delayed_work_pending(&bond->mii_work)) {
INIT_DELAYED_WORK(&bond->mii_work,
bond_mii_monitor);
queue_delayed_work(bond->wq,
&bond->mii_work, 0);
}
}
}
out:
return ret;
}
static DEVICE_ATTR(miimon, S_IRUGO | S_IWUSR,
bonding_show_miimon, bonding_store_miimon);
/*
* Show and set the primary slave. The store function is much
* simpler than bonding_store_slaves function because it only needs to
* handle one interface name.
* The bond must be a mode that supports a primary for this be
* set.
*/
static ssize_t bonding_show_primary(struct device *d,
struct device_attribute *attr,
char *buf)
{
int count = 0;
struct bonding *bond = to_bond(d);
if (bond->primary_slave)
count = sprintf(buf, "%s\n", bond->primary_slave->dev->name);
return count;
}
static ssize_t bonding_store_primary(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int i;
struct slave *slave;
struct bonding *bond = to_bond(d);
if (!rtnl_trylock())
return restart_syscall();
block_netpoll_tx();
read_lock(&bond->lock);
write_lock_bh(&bond->curr_slave_lock);
if (!USES_PRIMARY(bond->params.mode)) {
pr_info("%s: Unable to set primary slave; %s is in mode %d\n",
bond->dev->name, bond->dev->name, bond->params.mode);
} else {
bond_for_each_slave(bond, slave, i) {
if (strnicmp
(slave->dev->name, buf,
strlen(slave->dev->name)) == 0) {
pr_info("%s: Setting %s as primary slave.\n",
bond->dev->name, slave->dev->name);
bond->primary_slave = slave;
strcpy(bond->params.primary, slave->dev->name);
bond_select_active_slave(bond);
goto out;
}
}
/* if we got here, then we didn't match the name of any slave */
if (strlen(buf) == 0 || buf[0] == '\n') {
pr_info("%s: Setting primary slave to None.\n",
bond->dev->name);
bond->primary_slave = NULL;
bond_select_active_slave(bond);
} else {
pr_info("%s: Unable to set %.*s as primary slave as it is not a slave.\n",
bond->dev->name, (int)strlen(buf) - 1, buf);
}
}
out:
write_unlock_bh(&bond->curr_slave_lock);
read_unlock(&bond->lock);
unblock_netpoll_tx();
rtnl_unlock();
return count;
}
static DEVICE_ATTR(primary, S_IRUGO | S_IWUSR,
bonding_show_primary, bonding_store_primary);
/*
* Show and set the primary_reselect flag.
*/
static ssize_t bonding_show_primary_reselect(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%s %d\n",
pri_reselect_tbl[bond->params.primary_reselect].modename,
bond->params.primary_reselect);
}
static ssize_t bonding_store_primary_reselect(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (!rtnl_trylock())
return restart_syscall();
new_value = bond_parse_parm(buf, pri_reselect_tbl);
if (new_value < 0) {
pr_err("%s: Ignoring invalid primary_reselect value %.*s.\n",
bond->dev->name,
(int) strlen(buf) - 1, buf);
ret = -EINVAL;
goto out;
}
bond->params.primary_reselect = new_value;
pr_info("%s: setting primary_reselect to %s (%d).\n",
bond->dev->name, pri_reselect_tbl[new_value].modename,
new_value);
block_netpoll_tx();
read_lock(&bond->lock);
write_lock_bh(&bond->curr_slave_lock);
bond_select_active_slave(bond);
write_unlock_bh(&bond->curr_slave_lock);
read_unlock(&bond->lock);
unblock_netpoll_tx();
out:
rtnl_unlock();
return ret;
}
static DEVICE_ATTR(primary_reselect, S_IRUGO | S_IWUSR,
bonding_show_primary_reselect,
bonding_store_primary_reselect);
/*
* Show and set the use_carrier flag.
*/
static ssize_t bonding_show_carrier(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%d\n", bond->params.use_carrier);
}
static ssize_t bonding_store_carrier(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (sscanf(buf, "%d", &new_value) != 1) {
pr_err("%s: no use_carrier value specified.\n",
bond->dev->name);
ret = -EINVAL;
goto out;
}
if ((new_value == 0) || (new_value == 1)) {
bond->params.use_carrier = new_value;
pr_info("%s: Setting use_carrier to %d.\n",
bond->dev->name, new_value);
} else {
pr_info("%s: Ignoring invalid use_carrier value %d.\n",
bond->dev->name, new_value);
}
out:
return ret;
}
static DEVICE_ATTR(use_carrier, S_IRUGO | S_IWUSR,
bonding_show_carrier, bonding_store_carrier);
/*
* Show and set currently active_slave.
*/
static ssize_t bonding_show_active_slave(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct slave *curr;
struct bonding *bond = to_bond(d);
int count = 0;
read_lock(&bond->curr_slave_lock);
curr = bond->curr_active_slave;
read_unlock(&bond->curr_slave_lock);
if (USES_PRIMARY(bond->params.mode) && curr)
count = sprintf(buf, "%s\n", curr->dev->name);
return count;
}
static ssize_t bonding_store_active_slave(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int i;
struct slave *slave;
struct slave *old_active = NULL;
struct slave *new_active = NULL;
struct bonding *bond = to_bond(d);
if (!rtnl_trylock())
return restart_syscall();
block_netpoll_tx();
read_lock(&bond->lock);
write_lock_bh(&bond->curr_slave_lock);
if (!USES_PRIMARY(bond->params.mode))
pr_info("%s: Unable to change active slave; %s is in mode %d\n",
bond->dev->name, bond->dev->name, bond->params.mode);
else {
bond_for_each_slave(bond, slave, i) {
if (strnicmp
(slave->dev->name, buf,
strlen(slave->dev->name)) == 0) {
old_active = bond->curr_active_slave;
new_active = slave;
if (new_active == old_active) {
/* do nothing */
pr_info("%s: %s is already the current active slave.\n",
bond->dev->name,
slave->dev->name);
goto out;
}
else {
if ((new_active) &&
(old_active) &&
(new_active->link == BOND_LINK_UP) &&
IS_UP(new_active->dev)) {
pr_info("%s: Setting %s as active slave.\n",
bond->dev->name,
slave->dev->name);
bond_change_active_slave(bond, new_active);
}
else {
pr_info("%s: Could not set %s as active slave; either %s is down or the link is down.\n",
bond->dev->name,
slave->dev->name,
slave->dev->name);
}
goto out;
}
}
}
/* if we got here, then we didn't match the name of any slave */
if (strlen(buf) == 0 || buf[0] == '\n') {
pr_info("%s: Setting active slave to None.\n",
bond->dev->name);
bond->primary_slave = NULL;
bond_select_active_slave(bond);
} else {
pr_info("%s: Unable to set %.*s as active slave as it is not a slave.\n",
bond->dev->name, (int)strlen(buf) - 1, buf);
}
}
out:
write_unlock_bh(&bond->curr_slave_lock);
read_unlock(&bond->lock);
unblock_netpoll_tx();
rtnl_unlock();
return count;
}
static DEVICE_ATTR(active_slave, S_IRUGO | S_IWUSR,
bonding_show_active_slave, bonding_store_active_slave);
/*
* Show link status of the bond interface.
*/
static ssize_t bonding_show_mii_status(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct slave *curr;
struct bonding *bond = to_bond(d);
read_lock(&bond->curr_slave_lock);
curr = bond->curr_active_slave;
read_unlock(&bond->curr_slave_lock);
return sprintf(buf, "%s\n", curr ? "up" : "down");
}
static DEVICE_ATTR(mii_status, S_IRUGO, bonding_show_mii_status, NULL);
/*
* Show current 802.3ad aggregator ID.
*/
static ssize_t bonding_show_ad_aggregator(struct device *d,
struct device_attribute *attr,
char *buf)
{
int count = 0;
struct bonding *bond = to_bond(d);
if (bond->params.mode == BOND_MODE_8023AD) {
struct ad_info ad_info;
count = sprintf(buf, "%d\n",
(bond_3ad_get_active_agg_info(bond, &ad_info))
? 0 : ad_info.aggregator_id);
}
return count;
}
static DEVICE_ATTR(ad_aggregator, S_IRUGO, bonding_show_ad_aggregator, NULL);
/*
* Show number of active 802.3ad ports.
*/
static ssize_t bonding_show_ad_num_ports(struct device *d,
struct device_attribute *attr,
char *buf)
{
int count = 0;
struct bonding *bond = to_bond(d);
if (bond->params.mode == BOND_MODE_8023AD) {
struct ad_info ad_info;
count = sprintf(buf, "%d\n",
(bond_3ad_get_active_agg_info(bond, &ad_info))
? 0 : ad_info.ports);
}
return count;
}
static DEVICE_ATTR(ad_num_ports, S_IRUGO, bonding_show_ad_num_ports, NULL);
/*
* Show current 802.3ad actor key.
*/
static ssize_t bonding_show_ad_actor_key(struct device *d,
struct device_attribute *attr,
char *buf)
{
int count = 0;
struct bonding *bond = to_bond(d);
if (bond->params.mode == BOND_MODE_8023AD) {
struct ad_info ad_info;
count = sprintf(buf, "%d\n",
(bond_3ad_get_active_agg_info(bond, &ad_info))
? 0 : ad_info.actor_key);
}
return count;
}
static DEVICE_ATTR(ad_actor_key, S_IRUGO, bonding_show_ad_actor_key, NULL);
/*
* Show current 802.3ad partner key.
*/
static ssize_t bonding_show_ad_partner_key(struct device *d,
struct device_attribute *attr,
char *buf)
{
int count = 0;
struct bonding *bond = to_bond(d);
if (bond->params.mode == BOND_MODE_8023AD) {
struct ad_info ad_info;
count = sprintf(buf, "%d\n",
(bond_3ad_get_active_agg_info(bond, &ad_info))
? 0 : ad_info.partner_key);
}
return count;
}
static DEVICE_ATTR(ad_partner_key, S_IRUGO, bonding_show_ad_partner_key, NULL);
/*
* Show current 802.3ad partner mac.
*/
static ssize_t bonding_show_ad_partner_mac(struct device *d,
struct device_attribute *attr,
char *buf)
{
int count = 0;
struct bonding *bond = to_bond(d);
if (bond->params.mode == BOND_MODE_8023AD) {
struct ad_info ad_info;
if (!bond_3ad_get_active_agg_info(bond, &ad_info))
count = sprintf(buf, "%pM\n", ad_info.partner_system);
}
return count;
}
static DEVICE_ATTR(ad_partner_mac, S_IRUGO, bonding_show_ad_partner_mac, NULL);
/*
* Show the queue_ids of the slaves in the current bond.
*/
static ssize_t bonding_show_queue_id(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct slave *slave;
int i, res = 0;
struct bonding *bond = to_bond(d);
if (!rtnl_trylock())
return restart_syscall();
read_lock(&bond->lock);
bond_for_each_slave(bond, slave, i) {
if (res > (PAGE_SIZE - IFNAMSIZ - 6)) {
/* not enough space for another interface_name:queue_id pair */
if ((PAGE_SIZE - res) > 10)
res = PAGE_SIZE - 10;
res += sprintf(buf + res, "++more++ ");
break;
}
res += sprintf(buf + res, "%s:%d ",
slave->dev->name, slave->queue_id);
}
read_unlock(&bond->lock);
if (res)
buf[res-1] = '\n'; /* eat the leftover space */
rtnl_unlock();
return res;
}
/*
* Set the queue_ids of the slaves in the current bond. The bond
* interface must be enslaved for this to work.
*/
static ssize_t bonding_store_queue_id(struct device *d,
struct device_attribute *attr,
const char *buffer, size_t count)
{
struct slave *slave, *update_slave;
struct bonding *bond = to_bond(d);
u16 qid;
int i, ret = count;
char *delim;
struct net_device *sdev = NULL;
if (!rtnl_trylock())
return restart_syscall();
/* delim will point to queue id if successful */
delim = strchr(buffer, ':');
if (!delim)
goto err_no_cmd;
/*
* Terminate string that points to device name and bump it
* up one, so we can read the queue id there.
*/
*delim = '\0';
if (sscanf(++delim, "%hd\n", &qid) != 1)
goto err_no_cmd;
/* Check buffer length, valid ifname and queue id */
if (strlen(buffer) > IFNAMSIZ ||
!dev_valid_name(buffer) ||
qid > bond->params.tx_queues)
goto err_no_cmd;
/* Get the pointer to that interface if it exists */
sdev = __dev_get_by_name(dev_net(bond->dev), buffer);
if (!sdev)
goto err_no_cmd;
read_lock(&bond->lock);
/* Search for thes slave and check for duplicate qids */
update_slave = NULL;
bond_for_each_slave(bond, slave, i) {
if (sdev == slave->dev)
/*
* We don't need to check the matching
* slave for dups, since we're overwriting it
*/
update_slave = slave;
else if (qid && qid == slave->queue_id) {
goto err_no_cmd_unlock;
}
}
if (!update_slave)
goto err_no_cmd_unlock;
/* Actually set the qids for the slave */
update_slave->queue_id = qid;
read_unlock(&bond->lock);
out:
rtnl_unlock();
return ret;
err_no_cmd_unlock:
read_unlock(&bond->lock);
err_no_cmd:
pr_info("invalid input for queue_id set for %s.\n",
bond->dev->name);
ret = -EPERM;
goto out;
}
static DEVICE_ATTR(queue_id, S_IRUGO | S_IWUSR, bonding_show_queue_id,
bonding_store_queue_id);
/*
* Show and set the all_slaves_active flag.
*/
static ssize_t bonding_show_slaves_active(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%d\n", bond->params.all_slaves_active);
}
static ssize_t bonding_store_slaves_active(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int i, new_value, ret = count;
struct bonding *bond = to_bond(d);
struct slave *slave;
if (sscanf(buf, "%d", &new_value) != 1) {
pr_err("%s: no all_slaves_active value specified.\n",
bond->dev->name);
ret = -EINVAL;
goto out;
}
if (new_value == bond->params.all_slaves_active)
goto out;
if ((new_value == 0) || (new_value == 1)) {
bond->params.all_slaves_active = new_value;
} else {
pr_info("%s: Ignoring invalid all_slaves_active value %d.\n",
bond->dev->name, new_value);
ret = -EINVAL;
goto out;
}
bond_for_each_slave(bond, slave, i) {
if (!bond_is_active_slave(slave)) {
if (new_value)
slave->inactive = 0;
else
slave->inactive = 1;
}
}
out:
return ret;
}
static DEVICE_ATTR(all_slaves_active, S_IRUGO | S_IWUSR,
bonding_show_slaves_active, bonding_store_slaves_active);
/*
* Show and set the number of IGMP membership reports to send on link failure
*/
static ssize_t bonding_show_resend_igmp(struct device *d,
struct device_attribute *attr,
char *buf)
{
struct bonding *bond = to_bond(d);
return sprintf(buf, "%d\n", bond->params.resend_igmp);
}
static ssize_t bonding_store_resend_igmp(struct device *d,
struct device_attribute *attr,
const char *buf, size_t count)
{
int new_value, ret = count;
struct bonding *bond = to_bond(d);
if (sscanf(buf, "%d", &new_value) != 1) {
pr_err("%s: no resend_igmp value specified.\n",
bond->dev->name);
ret = -EINVAL;
goto out;
}
if (new_value < 0) {
pr_err("%s: Invalid resend_igmp value %d not in range 0-255; rejected.\n",
bond->dev->name, new_value);
ret = -EINVAL;
goto out;
}
pr_info("%s: Setting resend_igmp to %d.\n",
bond->dev->name, new_value);
bond->params.resend_igmp = new_value;
out:
return ret;
}
static DEVICE_ATTR(resend_igmp, S_IRUGO | S_IWUSR,
bonding_show_resend_igmp, bonding_store_resend_igmp);
static struct attribute *per_bond_attrs[] = {
&dev_attr_slaves.attr,
&dev_attr_mode.attr,
&dev_attr_fail_over_mac.attr,
&dev_attr_arp_validate.attr,
&dev_attr_arp_interval.attr,
&dev_attr_arp_ip_target.attr,
&dev_attr_downdelay.attr,
&dev_attr_updelay.attr,
&dev_attr_lacp_rate.attr,
&dev_attr_ad_select.attr,
&dev_attr_xmit_hash_policy.attr,
&dev_attr_num_grat_arp.attr,
&dev_attr_num_unsol_na.attr,
&dev_attr_miimon.attr,
&dev_attr_primary.attr,
&dev_attr_primary_reselect.attr,
&dev_attr_use_carrier.attr,
&dev_attr_active_slave.attr,
&dev_attr_mii_status.attr,
&dev_attr_ad_aggregator.attr,
&dev_attr_ad_num_ports.attr,
&dev_attr_ad_actor_key.attr,
&dev_attr_ad_partner_key.attr,
&dev_attr_ad_partner_mac.attr,
&dev_attr_queue_id.attr,
&dev_attr_all_slaves_active.attr,
&dev_attr_resend_igmp.attr,
NULL,
};
static struct attribute_group bonding_group = {
.name = "bonding",
.attrs = per_bond_attrs,
};
/*
* Initialize sysfs. This sets up the bonding_masters file in
* /sys/class/net.
*/
int bond_create_sysfs(void)
{
int ret;
ret = netdev_class_create_file(&class_attr_bonding_masters);
/*
* Permit multiple loads of the module by ignoring failures to
* create the bonding_masters sysfs file. Bonding devices
* created by second or subsequent loads of the module will
* not be listed in, or controllable by, bonding_masters, but
* will have the usual "bonding" sysfs directory.
*
* This is done to preserve backwards compatibility for
* initscripts/sysconfig, which load bonding multiple times to
* configure multiple bonding devices.
*/
if (ret == -EEXIST) {
/* Is someone being kinky and naming a device bonding_master? */
if (__dev_get_by_name(&init_net,
class_attr_bonding_masters.attr.name))
pr_err("network device named %s already exists in sysfs",
class_attr_bonding_masters.attr.name);
ret = 0;
}
return ret;
}
/*
* Remove /sys/class/net/bonding_masters.
*/
void bond_destroy_sysfs(void)
{
netdev_class_remove_file(&class_attr_bonding_masters);
}
/*
* Initialize sysfs for each bond. This sets up and registers
* the 'bondctl' directory for each individual bond under /sys/class/net.
*/
void bond_prepare_sysfs_group(struct bonding *bond)
{
bond->dev->sysfs_groups[0] = &bonding_group;
}
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