bond_main.c

h内核

		}
	}
}

/*
 * Add a Multicast address to slaves
 * according to mode
 */
static void bond_mc_add(struct bonding *bond, void *addr, int alen)
{
	if (USES_PRIMARY(bond->params.mode)) {
		/* write lock already acquired */
		if (bond->curr_active_slave) {
			dev_mc_add(bond->curr_active_slave->dev, addr, alen, 0);
		}
	} else {
		struct slave *slave;
		int i;
		bond_for_each_slave(bond, slave, i) {
			dev_mc_add(slave->dev, addr, alen, 0);
		}
	}
}

/*
 * Remove a multicast address from slave
 * according to mode
 */
static void bond_mc_delete(struct bonding *bond, void *addr, int alen)
{
	if (USES_PRIMARY(bond->params.mode)) {
		/* write lock already acquired */
		if (bond->curr_active_slave) {
			dev_mc_delete(bond->curr_active_slave->dev, addr, alen, 0);
		}
	} else {
		struct slave *slave;
		int i;
		bond_for_each_slave(bond, slave, i) {
			dev_mc_delete(slave->dev, addr, alen, 0);
		}
	}
}

/*
 * Totally destroys the mc_list in bond
 */
static void bond_mc_list_destroy(struct bonding *bond)
{
	struct dev_mc_list *dmi;

	dmi = bond->mc_list;
	while (dmi) {
		bond->mc_list = dmi->next;
		kfree(dmi);
		dmi = bond->mc_list;
	}
}

/*
 * Copy all the Multicast addresses from src to the bonding device dst
 */
static int bond_mc_list_copy(struct dev_mc_list *mc_list, struct bonding *bond, int gpf_flag)
{
	struct dev_mc_list *dmi, *new_dmi;

	for (dmi = mc_list; dmi; dmi = dmi->next) {
		new_dmi = kmalloc(sizeof(struct dev_mc_list), gpf_flag);

		if (!new_dmi) {
			/* FIXME: Potential memory leak !!! */
			return -ENOMEM;
		}

		new_dmi->next = bond->mc_list;
		bond->mc_list = new_dmi;
		new_dmi->dmi_addrlen = dmi->dmi_addrlen;
		memcpy(new_dmi->dmi_addr, dmi->dmi_addr, dmi->dmi_addrlen);
		new_dmi->dmi_users = dmi->dmi_users;
		new_dmi->dmi_gusers = dmi->dmi_gusers;
	}

	return 0;
}

/*
 * flush all members of flush->mc_list from device dev->mc_list
 */
static void bond_mc_list_flush(struct net_device *bond_dev, struct net_device *slave_dev)
{
	struct bonding *bond = bond_dev->priv;
	struct dev_mc_list *dmi;

	for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
		dev_mc_delete(slave_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
	}

	if (bond->params.mode == BOND_MODE_8023AD) {
		/* del lacpdu mc addr from mc list */
		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;

		dev_mc_delete(slave_dev, lacpdu_multicast, ETH_ALEN, 0);
	}
}

/*--------------------------- Active slave change ---------------------------*/

/*
 * Update the mc list and multicast-related flags for the new and
 * old active slaves (if any) according to the multicast mode, and
 * promiscuous flags unconditionally.
 */
static void bond_mc_swap(struct bonding *bond, struct slave *new_active, struct slave *old_active)
{
	struct dev_mc_list *dmi;

	if (!USES_PRIMARY(bond->params.mode)) {
		/* nothing to do -  mc list is already up-to-date on
		 * all slaves
		 */
		return;
	}

	if (old_active) {
		if (bond->dev->flags & IFF_PROMISC) {
			dev_set_promiscuity(old_active->dev, -1);
		}

		if (bond->dev->flags & IFF_ALLMULTI) {
			dev_set_allmulti(old_active->dev, -1);
		}

		for (dmi = bond->dev->mc_list; dmi; dmi = dmi->next) {
			dev_mc_delete(old_active->dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
		}
	}

	if (new_active) {
		if (bond->dev->flags & IFF_PROMISC) {
			dev_set_promiscuity(new_active->dev, 1);
		}

		if (bond->dev->flags & IFF_ALLMULTI) {
			dev_set_allmulti(new_active->dev, 1);
		}

		for (dmi = bond->dev->mc_list; dmi; dmi = dmi->next) {
			dev_mc_add(new_active->dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
		}
	}
}

/**
 * find_best_interface - select the best available slave to be the active one
 * @bond: our bonding struct
 *
 * Warning: Caller must hold curr_slave_lock for writing.
 */
static struct slave *bond_find_best_slave(struct bonding *bond)
{
	struct slave *new_active, *old_active;
	struct slave *bestslave = NULL;
	int mintime = bond->params.updelay;
	int i;

	new_active = old_active = bond->curr_active_slave;

	if (!new_active) { /* there were no active slaves left */
		if (bond->slave_cnt > 0) {  /* found one slave */
			new_active = bond->first_slave;
		} else {
			return NULL; /* still no slave, return NULL */
		}
	}

	/* first try the primary link; if arping, a link must tx/rx traffic
	 * before it can be considered the curr_active_slave - also, we would skip
	 * slaves between the curr_active_slave and primary_slave that may be up
	 * and able to arp
	 */
	if ((bond->primary_slave) &&
	    (!bond->params.arp_interval) &&
	    (IS_UP(bond->primary_slave->dev))) {
		new_active = bond->primary_slave;
	}

	/* remember where to stop iterating over the slaves */
	old_active = new_active;

	bond_for_each_slave_from(bond, new_active, i, old_active) {
		if (IS_UP(new_active->dev)) {
			if (new_active->link == BOND_LINK_UP) {
				return new_active;
			} else if (new_active->link == BOND_LINK_BACK) {
				/* link up, but waiting for stabilization */
				if (new_active->delay < mintime) {
					mintime = new_active->delay;
					bestslave = new_active;
				}
			}
		}
	}

	return bestslave;
}

/**
 * change_active_interface - change the active slave into the specified one
 * @bond: our bonding struct
 * @new: the new slave to make the active one
 *
 * Set the new slave to the bond's settings and unset them on the old
 * curr_active_slave.
 * Setting include flags, mc-list, promiscuity, allmulti, etc.
 *
 * If @new's link state is %BOND_LINK_BACK we'll set it to %BOND_LINK_UP,
 * because it is apparently the best available slave we have, even though its
 * updelay hasn't timed out yet.
 *
 * Warning: Caller must hold curr_slave_lock for writing.
 */
static void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
{
	struct slave *old_active = bond->curr_active_slave;

	if (old_active == new_active) {
		return;
	}

	if (new_active) {
		if (new_active->link == BOND_LINK_BACK) {
			if (USES_PRIMARY(bond->params.mode)) {
				printk(KERN_INFO DRV_NAME
				       ": %s: making interface %s the new "
				       "active one %d ms earlier.\n",
				       bond->dev->name, new_active->dev->name,
				       (bond->params.updelay - new_active->delay) * bond->params.miimon);
			}

			new_active->delay = 0;
			new_active->link = BOND_LINK_UP;
			new_active->jiffies = jiffies;

			if (bond->params.mode == BOND_MODE_8023AD) {
				bond_3ad_handle_link_change(new_active, BOND_LINK_UP);
			}

			if ((bond->params.mode == BOND_MODE_TLB) ||
			    (bond->params.mode == BOND_MODE_ALB)) {
				bond_alb_handle_link_change(bond, new_active, BOND_LINK_UP);
			}
		} else {
			if (USES_PRIMARY(bond->params.mode)) {
				printk(KERN_INFO DRV_NAME
				       ": %s: making interface %s the new "
				       "active one.\n",
				       bond->dev->name, new_active->dev->name);
			}
		}
	}

	if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
		if (old_active) {
			bond_set_slave_inactive_flags(old_active);
		}

		if (new_active) {
			bond_set_slave_active_flags(new_active);
		}
	}

	if (USES_PRIMARY(bond->params.mode)) {
		bond_mc_swap(bond, new_active, old_active);
	}

	if ((bond->params.mode == BOND_MODE_TLB) ||
	    (bond->params.mode == BOND_MODE_ALB)) {
		bond_alb_handle_active_change(bond, new_active);
	} else {
		bond->curr_active_slave = new_active;
	}
}

/**
 * bond_select_active_slave - select a new active slave, if needed
 * @bond: our bonding struct
 *
 * This functions shoud be called when one of the following occurs:
 * - The old curr_active_slave has been released or lost its link.
 * - The primary_slave has got its link back.
 * - A slave has got its link back and there's no old curr_active_slave.
 *
 * Warning: Caller must hold curr_slave_lock for writing.
 */
static void bond_select_active_slave(struct bonding *bond)
{
	struct slave *best_slave;

	best_slave = bond_find_best_slave(bond);
	if (best_slave != bond->curr_active_slave) {
		bond_change_active_slave(bond, best_slave);
	}
}

/*--------------------------- slave list handling ---------------------------*/

/*
 * This function attaches the slave to the end of list.
 *
 * bond->lock held for writing by caller.
 */
static void bond_attach_slave(struct bonding *bond, struct slave *new_slave)
{
	if (bond->first_slave == NULL) { /* attaching the first slave */
		new_slave->next = new_slave;
		new_slave->prev = new_slave;
		bond->first_slave = new_slave;
	} else {
		new_slave->next = bond->first_slave;
		new_slave->prev = bond->first_slave->prev;
		new_slave->next->prev = new_slave;
		new_slave->prev->next = new_slave;
	}

	bond->slave_cnt++;
}

/*
 * This function detaches the slave from the list.
 * WARNING: no check is made to verify if the slave effectively
 * belongs to <bond>.
 * Nothing is freed on return, structures are just unchained.
 * If any slave pointer in bond was pointing to <slave>,
 * it should be changed by the calling function.
 *
 * bond->lock held for writing by caller.
 */
static void bond_detach_slave(struct bonding *bond, struct slave *slave)
{
	if (slave->next) {
		slave->next->prev = slave->prev;
	}

	if (slave->prev) {
		slave->prev->next = slave->next;
	}

	if (bond->first_slave == slave) { /* slave is the first slave */
		if (bond->slave_cnt > 1) { /* there are more slave */
			bond->first_slave = slave->next;
		} else {
			bond->first_slave = NULL; /* slave was the last one */
		}
	}

	slave->next = NULL;
	slave->prev = NULL;
	bond->slave_cnt--;
}

/*---------------------------------- IOCTL ----------------------------------*/

static int bond_sethwaddr(struct net_device *bond_dev, struct net_device *slave_dev)
{
	dprintk("bond_dev=%p\n", bond_dev);
	dprintk("slave_dev=%p\n", slave_dev);
	dprintk("slave_dev->addr_len=%d\n", slave_dev->addr_len);
	memcpy(bond_dev->dev_addr, slave_dev->dev_addr, slave_dev->addr_len);
	return 0;
}

/* enslave device <slave> to bond device <master> */
static int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
{
	struct bonding *bond = bond_dev->priv;
	struct slave *new_slave = NULL;
	struct dev_mc_list *dmi;
	struct sockaddr addr;
	int link_reporting;
	int old_features = bond_dev->features;
	int res = 0;

	if (slave_dev->do_ioctl == NULL) {
		printk(KERN_WARNING DRV_NAME
		       ": Warning : no link monitoring support for %s\n",
		       slave_dev->name);
	}

	/* bond must be initialized by bond_open() before enslaving */
	if (!(bond_dev->flags & IFF_UP)) {
		dprintk("Error, master_dev is not up\n");
		return -EPERM;
	}

	/* already enslaved */
	if (slave_dev->flags & IFF_SLAVE) {
		dprintk("Error, Device was already enslaved\n");
		return -EBUSY;
	}

	/* vlan challenged mutual exclusion */
	/* no need to lock since we're protected by rtnl_lock */
	if (slave_dev->features & NETIF_F_VLAN_CHALLENGED) {
		dprintk("%s: NETIF_F_VLAN_CHALLENGED\n", slave_dev->name);
		if (!list_empty(&bond->vlan_list)) {
			printk(KERN_ERR DRV_NAME