bond_sysfs.c

来自「linux2.6.16版本」· C语言 代码 · 共 1,359 行 · 第 1/3 页

/*
 * 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.
 *
 */
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/device.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/string.h>
#include <linux/ctype.h>
#include <linux/inet.h>
#include <linux/rtnetlink.h>

/* #define BONDING_DEBUG 1 */
#include "bonding.h"
#define to_class_dev(obj) container_of(obj,struct class_device,kobj)
#define to_net_dev(class) container_of(class, struct net_device, class_dev)
#define to_bond(cd)	((struct bonding *)(to_net_dev(cd)->priv))

/*---------------------------- Declarations -------------------------------*/


extern struct list_head bond_dev_list;
extern struct bond_params bonding_defaults;
extern struct bond_parm_tbl bond_mode_tbl[];
extern struct bond_parm_tbl bond_lacp_tbl[];
extern struct bond_parm_tbl xmit_hashtype_tbl[];

static int expected_refcount = -1;
static struct class *netdev_class;
/*--------------------------- Data Structures -----------------------------*/

/* Bonding sysfs lock.  Why can't we just use the subsytem lock?
 * Because kobject_register tries to acquire the subsystem lock.  If
 * we already hold the lock (which we would if the user was creating
 * a new bond through the sysfs interface), we deadlock.
 * This lock is only needed when deleting a bond - we need to make sure
 * that we don't collide with an ongoing ioctl.
 */

struct rw_semaphore bonding_rwsem;




/*------------------------------ Functions --------------------------------*/

/*
 * "show" function for the bond_masters attribute.
 * The class parameter is ignored.
 */
static ssize_t bonding_show_bonds(struct class *cls, char *buffer)
{
	int res = 0;
	struct bonding *bond;

	down_read(&(bonding_rwsem));

	list_for_each_entry(bond, &bond_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(buffer + res, "++more++");
			break;
		}
		res += sprintf(buffer + res, "%s ",
			       bond->dev->name);
	}
	res += sprintf(buffer + res, "\n");
	res++;
	up_read(&(bonding_rwsem));
	return res;
}

/*
 * "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, const char *buffer, size_t count)
{
	char command[IFNAMSIZ + 1] = {0, };
	char *ifname;
	int res = count;
	struct bonding *bond;
	struct bonding *nxt;

	down_write(&(bonding_rwsem));
	sscanf(buffer, "%16s", command); /* IFNAMSIZ*/
	ifname = command + 1;
	if ((strlen(command) <= 1) ||
	    !dev_valid_name(ifname))
		goto err_no_cmd;

	if (command[0] == '+') {

		/* Check to see if the bond already exists. */
		list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list)
			if (strnicmp(bond->dev->name, ifname, IFNAMSIZ) == 0) {
				printk(KERN_ERR DRV_NAME
					": cannot add bond %s; it already exists\n",
					ifname);
				res = -EPERM;
				goto out;
			}

		printk(KERN_INFO DRV_NAME
			": %s is being created...\n", ifname);
		if (bond_create(ifname, &bonding_defaults, &bond)) {
			printk(KERN_INFO DRV_NAME
			": %s interface already exists. Bond creation failed.\n",
			ifname);
			res = -EPERM;
		}
		goto out;
	}

	if (command[0] == '-') {
		list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list)
			if (strnicmp(bond->dev->name, ifname, IFNAMSIZ) == 0) {
				rtnl_lock();
				/* check the ref count on the bond's kobject.
				 * If it's > expected, then there's a file open,
				 * and we have to fail.
				 */
				if (atomic_read(&bond->dev->class_dev.kobj.kref.refcount)
							> expected_refcount){
					rtnl_unlock();
					printk(KERN_INFO DRV_NAME
						": Unable remove bond %s due to open references.\n",
						ifname);
					res = -EPERM;
					goto out;
				}
				printk(KERN_INFO DRV_NAME
					": %s is being deleted...\n",
					bond->dev->name);
				unregister_netdevice(bond->dev);
				bond_deinit(bond->dev);
		        	bond_destroy_sysfs_entry(bond);
				rtnl_unlock();
				goto out;
			}

		printk(KERN_ERR DRV_NAME
			": unable to delete non-existent bond %s\n", ifname);
		res = -ENODEV;
		goto out;
	}

err_no_cmd:
	printk(KERN_ERR DRV_NAME
		": no command found in bonding_masters. Use +ifname or -ifname.\n");
	res = -EPERM;

	/* Always return either count or an error.  If you return 0, you'll
	 * get called forever, which is bad.
	 */
out:
	up_write(&(bonding_rwsem));
	return res;
}
/* 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->class_dev.kobj), &(master->class_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->class_dev.kobj), &(slave->class_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->class_dev.kobj), "master");
	sprintf(linkname,"slave_%s",slave->name);
	sysfs_remove_link(&(master->class_dev.kobj), linkname);
}


/*
 * Show the slaves in the current bond.
 */
static ssize_t bonding_show_slaves(struct class_device *cd, char *buf)
{
	struct slave *slave;
	int i, res = 0;
	struct bonding *bond = to_bond(cd);

	read_lock_bh(&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_bh(&bond->lock);
	res += sprintf(buf + res, "\n");
	res++;
	return res;
}

/*
 * Set the slaves in the current bond.  The bond interface must be
 * up for this to succeed.
 * This function is largely the same flow as bonding_update_bonds().
 */
static ssize_t bonding_store_slaves(struct class_device *cd, const char *buffer, size_t count)
{
	char command[IFNAMSIZ + 1] = { 0, };
	char *ifname;
	int i, res, found, ret = count;
	struct slave *slave;
	struct net_device *dev = NULL;
	struct bonding *bond = to_bond(cd);

	/* Quick sanity check -- is the bond interface up? */
	if (!(bond->dev->flags & IFF_UP)) {
		printk(KERN_ERR DRV_NAME
		       ": %s: Unable to update slaves because interface is down.\n",
		       bond->dev->name);
		ret = -EPERM;
		goto out;
	}

	/* Note:  We can't hold bond->lock here, as bond_create grabs it. */

	sscanf(buffer, "%16s", command); /* IFNAMSIZ*/
	ifname = command + 1;
	if ((strlen(command) <= 1) ||
	    !dev_valid_name(ifname))
		goto err_no_cmd;

	if (command[0] == '+') {

		/* Got a slave name in ifname.  Is it already in the list? */
		found = 0;
		read_lock_bh(&bond->lock);
		bond_for_each_slave(bond, slave, i)
			if (strnicmp(slave->dev->name, ifname, IFNAMSIZ) == 0) {
				printk(KERN_ERR DRV_NAME
				       ": %s: Interface %s is already enslaved!\n",
				       bond->dev->name, ifname);
				ret = -EPERM;
				read_unlock_bh(&bond->lock);
				goto out;
			}

		read_unlock_bh(&bond->lock);
		printk(KERN_INFO DRV_NAME ": %s: Adding slave %s.\n",
		       bond->dev->name, ifname);
		dev = dev_get_by_name(ifname);
		if (!dev) {
			printk(KERN_INFO DRV_NAME
			       ": %s: Interface %s does not exist!\n",
			       bond->dev->name, ifname);
			ret = -EPERM;
			goto out;
		}
		else
			dev_put(dev);

		if (dev->flags & IFF_UP) {
			printk(KERN_ERR DRV_NAME
			       ": %s: Error: Unable to enslave %s "
			       "because it is already up.\n",
			       bond->dev->name, dev->name);
			ret = -EPERM;
			goto out;
		}
		/* If this is the first slave, then we need to set
		   the master's hardware address to be the same as the
		   slave's. */
		if (!(*((u32 *) & (bond->dev->dev_addr[0])))) {
			memcpy(bond->dev->dev_addr, dev->dev_addr,
			       dev->addr_len);
		}

		/* Set the slave's MTU to match the bond */
		if (dev->mtu != bond->dev->mtu) {
			if (dev->change_mtu) {
				res = dev->change_mtu(dev,
						      bond->dev->mtu);
				if (res) {
					ret = res;
					goto out;
				}
			} else {
				dev->mtu = bond->dev->mtu;
			}
		}
		rtnl_lock();
		res = bond_enslave(bond->dev, dev);
		rtnl_unlock();
		if (res) {
			ret = res;
		}
		goto out;
	}

	if (command[0] == '-') {
		dev = NULL;
		bond_for_each_slave(bond, slave, i)
			if (strnicmp(slave->dev->name, ifname, IFNAMSIZ) == 0) {
				dev = slave->dev;
				break;
			}
		if (dev) {
			printk(KERN_INFO DRV_NAME ": %s: Removing slave %s\n",
				bond->dev->name, dev->name);
			rtnl_lock();
			res = bond_release(bond->dev, dev);
			rtnl_unlock();
			if (res) {
				ret = res;
				goto out;
			}
			/* set the slave MTU to the default */
			if (dev->change_mtu) {
				dev->change_mtu(dev, 1500);
			} else {
				dev->mtu = 1500;
			}
		}
		else {
			printk(KERN_ERR DRV_NAME ": unable to remove non-existent slave %s for bond %s.\n",
				ifname, bond->dev->name);
			ret = -ENODEV;
		}
		goto out;
	}

err_no_cmd:
	printk(KERN_ERR DRV_NAME ": no command found in slaves file for bond %s. Use +ifname or -ifname.\n", bond->dev->name);
	ret = -EPERM;

out:
	return ret;
}

static CLASS_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 class_device *cd, char *buf)
{
	struct bonding *bond = to_bond(cd);

	return sprintf(buf, "%s %d\n",
			bond_mode_tbl[bond->params.mode].modename,
			bond->params.mode) + 1;
}

static ssize_t bonding_store_mode(struct class_device *cd, const char *buf, size_t count)
{
	int new_value, ret = count;
	struct bonding *bond = to_bond(cd);

	if (bond->dev->flags & IFF_UP) {
		printk(KERN_ERR DRV_NAME
		       ": unable to update mode of %s because interface is up.\n",
		       bond->dev->name);
		ret = -EPERM;
		goto out;
	}

	new_value = bond_parse_parm((char *)buf, bond_mode_tbl);
	if (new_value < 0)  {
		printk(KERN_ERR DRV_NAME
		       ": %s: Ignoring invalid mode value %.*s.\n",
		       bond->dev->name,
		       (int)strlen(buf) - 1, buf);
		ret = -EINVAL;
		goto out;
	} else {
		bond->params.mode = new_value;
		bond_set_mode_ops(bond, bond->params.mode);
		printk(KERN_INFO DRV_NAME ": %s: setting mode to %s (%d).\n",
			bond->dev->name, bond_mode_tbl[new_value].modename, new_value);
	}
out:
	return ret;
}
static CLASS_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 class_device *cd, char *buf)
{
	int count;
	struct bonding *bond = to_bond(cd);

	if ((bond->params.mode != BOND_MODE_XOR) &&
	    (bond->params.mode != BOND_MODE_8023AD)) {
		// Not Applicable
		count = sprintf(buf, "NA\n") + 1;
	} else {
		count = sprintf(buf, "%s %d\n",
			xmit_hashtype_tbl[bond->params.xmit_policy].modename,
			bond->params.xmit_policy) + 1;