xref: /openbmc/linux/drivers/net/bonding/bond_main.c (revision 6aa7de05)
1 /*
2  * originally based on the dummy device.
3  *
4  * Copyright 1999, Thomas Davis, tadavis@lbl.gov.
5  * Licensed under the GPL. Based on dummy.c, and eql.c devices.
6  *
7  * bonding.c: an Ethernet Bonding driver
8  *
9  * This is useful to talk to a Cisco EtherChannel compatible equipment:
10  *	Cisco 5500
11  *	Sun Trunking (Solaris)
12  *	Alteon AceDirector Trunks
13  *	Linux Bonding
14  *	and probably many L2 switches ...
15  *
16  * How it works:
17  *    ifconfig bond0 ipaddress netmask up
18  *      will setup a network device, with an ip address.  No mac address
19  *	will be assigned at this time.  The hw mac address will come from
20  *	the first slave bonded to the channel.  All slaves will then use
21  *	this hw mac address.
22  *
23  *    ifconfig bond0 down
24  *         will release all slaves, marking them as down.
25  *
26  *    ifenslave bond0 eth0
27  *	will attach eth0 to bond0 as a slave.  eth0 hw mac address will either
28  *	a: be used as initial mac address
29  *	b: if a hw mac address already is there, eth0's hw mac address
30  *	   will then be set from bond0.
31  *
32  */
33 
34 #include <linux/kernel.h>
35 #include <linux/module.h>
36 #include <linux/types.h>
37 #include <linux/fcntl.h>
38 #include <linux/interrupt.h>
39 #include <linux/ptrace.h>
40 #include <linux/ioport.h>
41 #include <linux/in.h>
42 #include <net/ip.h>
43 #include <linux/ip.h>
44 #include <linux/tcp.h>
45 #include <linux/udp.h>
46 #include <linux/slab.h>
47 #include <linux/string.h>
48 #include <linux/init.h>
49 #include <linux/timer.h>
50 #include <linux/socket.h>
51 #include <linux/ctype.h>
52 #include <linux/inet.h>
53 #include <linux/bitops.h>
54 #include <linux/io.h>
55 #include <asm/dma.h>
56 #include <linux/uaccess.h>
57 #include <linux/errno.h>
58 #include <linux/netdevice.h>
59 #include <linux/inetdevice.h>
60 #include <linux/igmp.h>
61 #include <linux/etherdevice.h>
62 #include <linux/skbuff.h>
63 #include <net/sock.h>
64 #include <linux/rtnetlink.h>
65 #include <linux/smp.h>
66 #include <linux/if_ether.h>
67 #include <net/arp.h>
68 #include <linux/mii.h>
69 #include <linux/ethtool.h>
70 #include <linux/if_vlan.h>
71 #include <linux/if_bonding.h>
72 #include <linux/jiffies.h>
73 #include <linux/preempt.h>
74 #include <net/route.h>
75 #include <net/net_namespace.h>
76 #include <net/netns/generic.h>
77 #include <net/pkt_sched.h>
78 #include <linux/rculist.h>
79 #include <net/flow_dissector.h>
80 #include <net/switchdev.h>
81 #include <net/bonding.h>
82 #include <net/bond_3ad.h>
83 #include <net/bond_alb.h>
84 
85 #include "bonding_priv.h"
86 
87 /*---------------------------- Module parameters ----------------------------*/
88 
89 /* monitor all links that often (in milliseconds). <=0 disables monitoring */
90 
91 static int max_bonds	= BOND_DEFAULT_MAX_BONDS;
92 static int tx_queues	= BOND_DEFAULT_TX_QUEUES;
93 static int num_peer_notif = 1;
94 static int miimon;
95 static int updelay;
96 static int downdelay;
97 static int use_carrier	= 1;
98 static char *mode;
99 static char *primary;
100 static char *primary_reselect;
101 static char *lacp_rate;
102 static int min_links;
103 static char *ad_select;
104 static char *xmit_hash_policy;
105 static int arp_interval;
106 static char *arp_ip_target[BOND_MAX_ARP_TARGETS];
107 static char *arp_validate;
108 static char *arp_all_targets;
109 static char *fail_over_mac;
110 static int all_slaves_active;
111 static struct bond_params bonding_defaults;
112 static int resend_igmp = BOND_DEFAULT_RESEND_IGMP;
113 static int packets_per_slave = 1;
114 static int lp_interval = BOND_ALB_DEFAULT_LP_INTERVAL;
115 
116 module_param(max_bonds, int, 0);
117 MODULE_PARM_DESC(max_bonds, "Max number of bonded devices");
118 module_param(tx_queues, int, 0);
119 MODULE_PARM_DESC(tx_queues, "Max number of transmit queues (default = 16)");
120 module_param_named(num_grat_arp, num_peer_notif, int, 0644);
121 MODULE_PARM_DESC(num_grat_arp, "Number of peer notifications to send on "
122 			       "failover event (alias of num_unsol_na)");
123 module_param_named(num_unsol_na, num_peer_notif, int, 0644);
124 MODULE_PARM_DESC(num_unsol_na, "Number of peer notifications to send on "
125 			       "failover event (alias of num_grat_arp)");
126 module_param(miimon, int, 0);
127 MODULE_PARM_DESC(miimon, "Link check interval in milliseconds");
128 module_param(updelay, int, 0);
129 MODULE_PARM_DESC(updelay, "Delay before considering link up, in milliseconds");
130 module_param(downdelay, int, 0);
131 MODULE_PARM_DESC(downdelay, "Delay before considering link down, "
132 			    "in milliseconds");
133 module_param(use_carrier, int, 0);
134 MODULE_PARM_DESC(use_carrier, "Use netif_carrier_ok (vs MII ioctls) in miimon; "
135 			      "0 for off, 1 for on (default)");
136 module_param(mode, charp, 0);
137 MODULE_PARM_DESC(mode, "Mode of operation; 0 for balance-rr, "
138 		       "1 for active-backup, 2 for balance-xor, "
139 		       "3 for broadcast, 4 for 802.3ad, 5 for balance-tlb, "
140 		       "6 for balance-alb");
141 module_param(primary, charp, 0);
142 MODULE_PARM_DESC(primary, "Primary network device to use");
143 module_param(primary_reselect, charp, 0);
144 MODULE_PARM_DESC(primary_reselect, "Reselect primary slave "
145 				   "once it comes up; "
146 				   "0 for always (default), "
147 				   "1 for only if speed of primary is "
148 				   "better, "
149 				   "2 for only on active slave "
150 				   "failure");
151 module_param(lacp_rate, charp, 0);
152 MODULE_PARM_DESC(lacp_rate, "LACPDU tx rate to request from 802.3ad partner; "
153 			    "0 for slow, 1 for fast");
154 module_param(ad_select, charp, 0);
155 MODULE_PARM_DESC(ad_select, "802.3ad aggregation selection logic; "
156 			    "0 for stable (default), 1 for bandwidth, "
157 			    "2 for count");
158 module_param(min_links, int, 0);
159 MODULE_PARM_DESC(min_links, "Minimum number of available links before turning on carrier");
160 
161 module_param(xmit_hash_policy, charp, 0);
162 MODULE_PARM_DESC(xmit_hash_policy, "balance-xor and 802.3ad hashing method; "
163 				   "0 for layer 2 (default), 1 for layer 3+4, "
164 				   "2 for layer 2+3, 3 for encap layer 2+3, "
165 				   "4 for encap layer 3+4");
166 module_param(arp_interval, int, 0);
167 MODULE_PARM_DESC(arp_interval, "arp interval in milliseconds");
168 module_param_array(arp_ip_target, charp, NULL, 0);
169 MODULE_PARM_DESC(arp_ip_target, "arp targets in n.n.n.n form");
170 module_param(arp_validate, charp, 0);
171 MODULE_PARM_DESC(arp_validate, "validate src/dst of ARP probes; "
172 			       "0 for none (default), 1 for active, "
173 			       "2 for backup, 3 for all");
174 module_param(arp_all_targets, charp, 0);
175 MODULE_PARM_DESC(arp_all_targets, "fail on any/all arp targets timeout; 0 for any (default), 1 for all");
176 module_param(fail_over_mac, charp, 0);
177 MODULE_PARM_DESC(fail_over_mac, "For active-backup, do not set all slaves to "
178 				"the same MAC; 0 for none (default), "
179 				"1 for active, 2 for follow");
180 module_param(all_slaves_active, int, 0);
181 MODULE_PARM_DESC(all_slaves_active, "Keep all frames received on an interface "
182 				     "by setting active flag for all slaves; "
183 				     "0 for never (default), 1 for always.");
184 module_param(resend_igmp, int, 0);
185 MODULE_PARM_DESC(resend_igmp, "Number of IGMP membership reports to send on "
186 			      "link failure");
187 module_param(packets_per_slave, int, 0);
188 MODULE_PARM_DESC(packets_per_slave, "Packets to send per slave in balance-rr "
189 				    "mode; 0 for a random slave, 1 packet per "
190 				    "slave (default), >1 packets per slave.");
191 module_param(lp_interval, uint, 0);
192 MODULE_PARM_DESC(lp_interval, "The number of seconds between instances where "
193 			      "the bonding driver sends learning packets to "
194 			      "each slaves peer switch. The default is 1.");
195 
196 /*----------------------------- Global variables ----------------------------*/
197 
198 #ifdef CONFIG_NET_POLL_CONTROLLER
199 atomic_t netpoll_block_tx = ATOMIC_INIT(0);
200 #endif
201 
202 unsigned int bond_net_id __read_mostly;
203 
204 /*-------------------------- Forward declarations ---------------------------*/
205 
206 static int bond_init(struct net_device *bond_dev);
207 static void bond_uninit(struct net_device *bond_dev);
208 static void bond_get_stats(struct net_device *bond_dev,
209 			   struct rtnl_link_stats64 *stats);
210 static void bond_slave_arr_handler(struct work_struct *work);
211 static bool bond_time_in_interval(struct bonding *bond, unsigned long last_act,
212 				  int mod);
213 
214 /*---------------------------- General routines -----------------------------*/
215 
216 const char *bond_mode_name(int mode)
217 {
218 	static const char *names[] = {
219 		[BOND_MODE_ROUNDROBIN] = "load balancing (round-robin)",
220 		[BOND_MODE_ACTIVEBACKUP] = "fault-tolerance (active-backup)",
221 		[BOND_MODE_XOR] = "load balancing (xor)",
222 		[BOND_MODE_BROADCAST] = "fault-tolerance (broadcast)",
223 		[BOND_MODE_8023AD] = "IEEE 802.3ad Dynamic link aggregation",
224 		[BOND_MODE_TLB] = "transmit load balancing",
225 		[BOND_MODE_ALB] = "adaptive load balancing",
226 	};
227 
228 	if (mode < BOND_MODE_ROUNDROBIN || mode > BOND_MODE_ALB)
229 		return "unknown";
230 
231 	return names[mode];
232 }
233 
234 /*---------------------------------- VLAN -----------------------------------*/
235 
236 /**
237  * bond_dev_queue_xmit - Prepare skb for xmit.
238  *
239  * @bond: bond device that got this skb for tx.
240  * @skb: hw accel VLAN tagged skb to transmit
241  * @slave_dev: slave that is supposed to xmit this skbuff
242  */
243 void bond_dev_queue_xmit(struct bonding *bond, struct sk_buff *skb,
244 			struct net_device *slave_dev)
245 {
246 	skb->dev = slave_dev;
247 
248 	BUILD_BUG_ON(sizeof(skb->queue_mapping) !=
249 		     sizeof(qdisc_skb_cb(skb)->slave_dev_queue_mapping));
250 	skb->queue_mapping = qdisc_skb_cb(skb)->slave_dev_queue_mapping;
251 
252 	if (unlikely(netpoll_tx_running(bond->dev)))
253 		bond_netpoll_send_skb(bond_get_slave_by_dev(bond, slave_dev), skb);
254 	else
255 		dev_queue_xmit(skb);
256 }
257 
258 /* In the following 2 functions, bond_vlan_rx_add_vid and bond_vlan_rx_kill_vid,
259  * We don't protect the slave list iteration with a lock because:
260  * a. This operation is performed in IOCTL context,
261  * b. The operation is protected by the RTNL semaphore in the 8021q code,
262  * c. Holding a lock with BH disabled while directly calling a base driver
263  *    entry point is generally a BAD idea.
264  *
265  * The design of synchronization/protection for this operation in the 8021q
266  * module is good for one or more VLAN devices over a single physical device
267  * and cannot be extended for a teaming solution like bonding, so there is a
268  * potential race condition here where a net device from the vlan group might
269  * be referenced (either by a base driver or the 8021q code) while it is being
270  * removed from the system. However, it turns out we're not making matters
271  * worse, and if it works for regular VLAN usage it will work here too.
272 */
273 
274 /**
275  * bond_vlan_rx_add_vid - Propagates adding an id to slaves
276  * @bond_dev: bonding net device that got called
277  * @vid: vlan id being added
278  */
279 static int bond_vlan_rx_add_vid(struct net_device *bond_dev,
280 				__be16 proto, u16 vid)
281 {
282 	struct bonding *bond = netdev_priv(bond_dev);
283 	struct slave *slave, *rollback_slave;
284 	struct list_head *iter;
285 	int res;
286 
287 	bond_for_each_slave(bond, slave, iter) {
288 		res = vlan_vid_add(slave->dev, proto, vid);
289 		if (res)
290 			goto unwind;
291 	}
292 
293 	return 0;
294 
295 unwind:
296 	/* unwind to the slave that failed */
297 	bond_for_each_slave(bond, rollback_slave, iter) {
298 		if (rollback_slave == slave)
299 			break;
300 
301 		vlan_vid_del(rollback_slave->dev, proto, vid);
302 	}
303 
304 	return res;
305 }
306 
307 /**
308  * bond_vlan_rx_kill_vid - Propagates deleting an id to slaves
309  * @bond_dev: bonding net device that got called
310  * @vid: vlan id being removed
311  */
312 static int bond_vlan_rx_kill_vid(struct net_device *bond_dev,
313 				 __be16 proto, u16 vid)
314 {
315 	struct bonding *bond = netdev_priv(bond_dev);
316 	struct list_head *iter;
317 	struct slave *slave;
318 
319 	bond_for_each_slave(bond, slave, iter)
320 		vlan_vid_del(slave->dev, proto, vid);
321 
322 	if (bond_is_lb(bond))
323 		bond_alb_clear_vlan(bond, vid);
324 
325 	return 0;
326 }
327 
328 /*------------------------------- Link status -------------------------------*/
329 
330 /* Set the carrier state for the master according to the state of its
331  * slaves.  If any slaves are up, the master is up.  In 802.3ad mode,
332  * do special 802.3ad magic.
333  *
334  * Returns zero if carrier state does not change, nonzero if it does.
335  */
336 int bond_set_carrier(struct bonding *bond)
337 {
338 	struct list_head *iter;
339 	struct slave *slave;
340 
341 	if (!bond_has_slaves(bond))
342 		goto down;
343 
344 	if (BOND_MODE(bond) == BOND_MODE_8023AD)
345 		return bond_3ad_set_carrier(bond);
346 
347 	bond_for_each_slave(bond, slave, iter) {
348 		if (slave->link == BOND_LINK_UP) {
349 			if (!netif_carrier_ok(bond->dev)) {
350 				netif_carrier_on(bond->dev);
351 				return 1;
352 			}
353 			return 0;
354 		}
355 	}
356 
357 down:
358 	if (netif_carrier_ok(bond->dev)) {
359 		netif_carrier_off(bond->dev);
360 		return 1;
361 	}
362 	return 0;
363 }
364 
365 /* Get link speed and duplex from the slave's base driver
366  * using ethtool. If for some reason the call fails or the
367  * values are invalid, set speed and duplex to -1,
368  * and return. Return 1 if speed or duplex settings are
369  * UNKNOWN; 0 otherwise.
370  */
371 static int bond_update_speed_duplex(struct slave *slave)
372 {
373 	struct net_device *slave_dev = slave->dev;
374 	struct ethtool_link_ksettings ecmd;
375 	int res;
376 
377 	slave->speed = SPEED_UNKNOWN;
378 	slave->duplex = DUPLEX_UNKNOWN;
379 
380 	res = __ethtool_get_link_ksettings(slave_dev, &ecmd);
381 	if (res < 0)
382 		return 1;
383 	if (ecmd.base.speed == 0 || ecmd.base.speed == ((__u32)-1))
384 		return 1;
385 	switch (ecmd.base.duplex) {
386 	case DUPLEX_FULL:
387 	case DUPLEX_HALF:
388 		break;
389 	default:
390 		return 1;
391 	}
392 
393 	slave->speed = ecmd.base.speed;
394 	slave->duplex = ecmd.base.duplex;
395 
396 	return 0;
397 }
398 
399 const char *bond_slave_link_status(s8 link)
400 {
401 	switch (link) {
402 	case BOND_LINK_UP:
403 		return "up";
404 	case BOND_LINK_FAIL:
405 		return "going down";
406 	case BOND_LINK_DOWN:
407 		return "down";
408 	case BOND_LINK_BACK:
409 		return "going back";
410 	default:
411 		return "unknown";
412 	}
413 }
414 
415 /* if <dev> supports MII link status reporting, check its link status.
416  *
417  * We either do MII/ETHTOOL ioctls, or check netif_carrier_ok(),
418  * depending upon the setting of the use_carrier parameter.
419  *
420  * Return either BMSR_LSTATUS, meaning that the link is up (or we
421  * can't tell and just pretend it is), or 0, meaning that the link is
422  * down.
423  *
424  * If reporting is non-zero, instead of faking link up, return -1 if
425  * both ETHTOOL and MII ioctls fail (meaning the device does not
426  * support them).  If use_carrier is set, return whatever it says.
427  * It'd be nice if there was a good way to tell if a driver supports
428  * netif_carrier, but there really isn't.
429  */
430 static int bond_check_dev_link(struct bonding *bond,
431 			       struct net_device *slave_dev, int reporting)
432 {
433 	const struct net_device_ops *slave_ops = slave_dev->netdev_ops;
434 	int (*ioctl)(struct net_device *, struct ifreq *, int);
435 	struct ifreq ifr;
436 	struct mii_ioctl_data *mii;
437 
438 	if (!reporting && !netif_running(slave_dev))
439 		return 0;
440 
441 	if (bond->params.use_carrier)
442 		return netif_carrier_ok(slave_dev) ? BMSR_LSTATUS : 0;
443 
444 	/* Try to get link status using Ethtool first. */
445 	if (slave_dev->ethtool_ops->get_link)
446 		return slave_dev->ethtool_ops->get_link(slave_dev) ?
447 			BMSR_LSTATUS : 0;
448 
449 	/* Ethtool can't be used, fallback to MII ioctls. */
450 	ioctl = slave_ops->ndo_do_ioctl;
451 	if (ioctl) {
452 		/* TODO: set pointer to correct ioctl on a per team member
453 		 *       bases to make this more efficient. that is, once
454 		 *       we determine the correct ioctl, we will always
455 		 *       call it and not the others for that team
456 		 *       member.
457 		 */
458 
459 		/* We cannot assume that SIOCGMIIPHY will also read a
460 		 * register; not all network drivers (e.g., e100)
461 		 * support that.
462 		 */
463 
464 		/* Yes, the mii is overlaid on the ifreq.ifr_ifru */
465 		strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
466 		mii = if_mii(&ifr);
467 		if (ioctl(slave_dev, &ifr, SIOCGMIIPHY) == 0) {
468 			mii->reg_num = MII_BMSR;
469 			if (ioctl(slave_dev, &ifr, SIOCGMIIREG) == 0)
470 				return mii->val_out & BMSR_LSTATUS;
471 		}
472 	}
473 
474 	/* If reporting, report that either there's no dev->do_ioctl,
475 	 * or both SIOCGMIIREG and get_link failed (meaning that we
476 	 * cannot report link status).  If not reporting, pretend
477 	 * we're ok.
478 	 */
479 	return reporting ? -1 : BMSR_LSTATUS;
480 }
481 
482 /*----------------------------- Multicast list ------------------------------*/
483 
484 /* Push the promiscuity flag down to appropriate slaves */
485 static int bond_set_promiscuity(struct bonding *bond, int inc)
486 {
487 	struct list_head *iter;
488 	int err = 0;
489 
490 	if (bond_uses_primary(bond)) {
491 		struct slave *curr_active = rtnl_dereference(bond->curr_active_slave);
492 
493 		if (curr_active)
494 			err = dev_set_promiscuity(curr_active->dev, inc);
495 	} else {
496 		struct slave *slave;
497 
498 		bond_for_each_slave(bond, slave, iter) {
499 			err = dev_set_promiscuity(slave->dev, inc);
500 			if (err)
501 				return err;
502 		}
503 	}
504 	return err;
505 }
506 
507 /* Push the allmulti flag down to all slaves */
508 static int bond_set_allmulti(struct bonding *bond, int inc)
509 {
510 	struct list_head *iter;
511 	int err = 0;
512 
513 	if (bond_uses_primary(bond)) {
514 		struct slave *curr_active = rtnl_dereference(bond->curr_active_slave);
515 
516 		if (curr_active)
517 			err = dev_set_allmulti(curr_active->dev, inc);
518 	} else {
519 		struct slave *slave;
520 
521 		bond_for_each_slave(bond, slave, iter) {
522 			err = dev_set_allmulti(slave->dev, inc);
523 			if (err)
524 				return err;
525 		}
526 	}
527 	return err;
528 }
529 
530 /* Retrieve the list of registered multicast addresses for the bonding
531  * device and retransmit an IGMP JOIN request to the current active
532  * slave.
533  */
534 static void bond_resend_igmp_join_requests_delayed(struct work_struct *work)
535 {
536 	struct bonding *bond = container_of(work, struct bonding,
537 					    mcast_work.work);
538 
539 	if (!rtnl_trylock()) {
540 		queue_delayed_work(bond->wq, &bond->mcast_work, 1);
541 		return;
542 	}
543 	call_netdevice_notifiers(NETDEV_RESEND_IGMP, bond->dev);
544 
545 	if (bond->igmp_retrans > 1) {
546 		bond->igmp_retrans--;
547 		queue_delayed_work(bond->wq, &bond->mcast_work, HZ/5);
548 	}
549 	rtnl_unlock();
550 }
551 
552 /* Flush bond's hardware addresses from slave */
553 static void bond_hw_addr_flush(struct net_device *bond_dev,
554 			       struct net_device *slave_dev)
555 {
556 	struct bonding *bond = netdev_priv(bond_dev);
557 
558 	dev_uc_unsync(slave_dev, bond_dev);
559 	dev_mc_unsync(slave_dev, bond_dev);
560 
561 	if (BOND_MODE(bond) == BOND_MODE_8023AD) {
562 		/* del lacpdu mc addr from mc list */
563 		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
564 
565 		dev_mc_del(slave_dev, lacpdu_multicast);
566 	}
567 }
568 
569 /*--------------------------- Active slave change ---------------------------*/
570 
571 /* Update the hardware address list and promisc/allmulti for the new and
572  * old active slaves (if any).  Modes that are not using primary keep all
573  * slaves up date at all times; only the modes that use primary need to call
574  * this function to swap these settings during a failover.
575  */
576 static void bond_hw_addr_swap(struct bonding *bond, struct slave *new_active,
577 			      struct slave *old_active)
578 {
579 	if (old_active) {
580 		if (bond->dev->flags & IFF_PROMISC)
581 			dev_set_promiscuity(old_active->dev, -1);
582 
583 		if (bond->dev->flags & IFF_ALLMULTI)
584 			dev_set_allmulti(old_active->dev, -1);
585 
586 		bond_hw_addr_flush(bond->dev, old_active->dev);
587 	}
588 
589 	if (new_active) {
590 		/* FIXME: Signal errors upstream. */
591 		if (bond->dev->flags & IFF_PROMISC)
592 			dev_set_promiscuity(new_active->dev, 1);
593 
594 		if (bond->dev->flags & IFF_ALLMULTI)
595 			dev_set_allmulti(new_active->dev, 1);
596 
597 		netif_addr_lock_bh(bond->dev);
598 		dev_uc_sync(new_active->dev, bond->dev);
599 		dev_mc_sync(new_active->dev, bond->dev);
600 		netif_addr_unlock_bh(bond->dev);
601 	}
602 }
603 
604 /**
605  * bond_set_dev_addr - clone slave's address to bond
606  * @bond_dev: bond net device
607  * @slave_dev: slave net device
608  *
609  * Should be called with RTNL held.
610  */
611 static void bond_set_dev_addr(struct net_device *bond_dev,
612 			      struct net_device *slave_dev)
613 {
614 	netdev_dbg(bond_dev, "bond_dev=%p slave_dev=%p slave_dev->name=%s slave_dev->addr_len=%d\n",
615 		   bond_dev, slave_dev, slave_dev->name, slave_dev->addr_len);
616 	memcpy(bond_dev->dev_addr, slave_dev->dev_addr, slave_dev->addr_len);
617 	bond_dev->addr_assign_type = NET_ADDR_STOLEN;
618 	call_netdevice_notifiers(NETDEV_CHANGEADDR, bond_dev);
619 }
620 
621 static struct slave *bond_get_old_active(struct bonding *bond,
622 					 struct slave *new_active)
623 {
624 	struct slave *slave;
625 	struct list_head *iter;
626 
627 	bond_for_each_slave(bond, slave, iter) {
628 		if (slave == new_active)
629 			continue;
630 
631 		if (ether_addr_equal(bond->dev->dev_addr, slave->dev->dev_addr))
632 			return slave;
633 	}
634 
635 	return NULL;
636 }
637 
638 /* bond_do_fail_over_mac
639  *
640  * Perform special MAC address swapping for fail_over_mac settings
641  *
642  * Called with RTNL
643  */
644 static void bond_do_fail_over_mac(struct bonding *bond,
645 				  struct slave *new_active,
646 				  struct slave *old_active)
647 {
648 	u8 tmp_mac[MAX_ADDR_LEN];
649 	struct sockaddr_storage ss;
650 	int rv;
651 
652 	switch (bond->params.fail_over_mac) {
653 	case BOND_FOM_ACTIVE:
654 		if (new_active)
655 			bond_set_dev_addr(bond->dev, new_active->dev);
656 		break;
657 	case BOND_FOM_FOLLOW:
658 		/* if new_active && old_active, swap them
659 		 * if just old_active, do nothing (going to no active slave)
660 		 * if just new_active, set new_active to bond's MAC
661 		 */
662 		if (!new_active)
663 			return;
664 
665 		if (!old_active)
666 			old_active = bond_get_old_active(bond, new_active);
667 
668 		if (old_active) {
669 			bond_hw_addr_copy(tmp_mac, new_active->dev->dev_addr,
670 					  new_active->dev->addr_len);
671 			bond_hw_addr_copy(ss.__data,
672 					  old_active->dev->dev_addr,
673 					  old_active->dev->addr_len);
674 			ss.ss_family = new_active->dev->type;
675 		} else {
676 			bond_hw_addr_copy(ss.__data, bond->dev->dev_addr,
677 					  bond->dev->addr_len);
678 			ss.ss_family = bond->dev->type;
679 		}
680 
681 		rv = dev_set_mac_address(new_active->dev,
682 					 (struct sockaddr *)&ss);
683 		if (rv) {
684 			netdev_err(bond->dev, "Error %d setting MAC of slave %s\n",
685 				   -rv, new_active->dev->name);
686 			goto out;
687 		}
688 
689 		if (!old_active)
690 			goto out;
691 
692 		bond_hw_addr_copy(ss.__data, tmp_mac,
693 				  new_active->dev->addr_len);
694 		ss.ss_family = old_active->dev->type;
695 
696 		rv = dev_set_mac_address(old_active->dev,
697 					 (struct sockaddr *)&ss);
698 		if (rv)
699 			netdev_err(bond->dev, "Error %d setting MAC of slave %s\n",
700 				   -rv, new_active->dev->name);
701 out:
702 		break;
703 	default:
704 		netdev_err(bond->dev, "bond_do_fail_over_mac impossible: bad policy %d\n",
705 			   bond->params.fail_over_mac);
706 		break;
707 	}
708 
709 }
710 
711 static struct slave *bond_choose_primary_or_current(struct bonding *bond)
712 {
713 	struct slave *prim = rtnl_dereference(bond->primary_slave);
714 	struct slave *curr = rtnl_dereference(bond->curr_active_slave);
715 
716 	if (!prim || prim->link != BOND_LINK_UP) {
717 		if (!curr || curr->link != BOND_LINK_UP)
718 			return NULL;
719 		return curr;
720 	}
721 
722 	if (bond->force_primary) {
723 		bond->force_primary = false;
724 		return prim;
725 	}
726 
727 	if (!curr || curr->link != BOND_LINK_UP)
728 		return prim;
729 
730 	/* At this point, prim and curr are both up */
731 	switch (bond->params.primary_reselect) {
732 	case BOND_PRI_RESELECT_ALWAYS:
733 		return prim;
734 	case BOND_PRI_RESELECT_BETTER:
735 		if (prim->speed < curr->speed)
736 			return curr;
737 		if (prim->speed == curr->speed && prim->duplex <= curr->duplex)
738 			return curr;
739 		return prim;
740 	case BOND_PRI_RESELECT_FAILURE:
741 		return curr;
742 	default:
743 		netdev_err(bond->dev, "impossible primary_reselect %d\n",
744 			   bond->params.primary_reselect);
745 		return curr;
746 	}
747 }
748 
749 /**
750  * bond_find_best_slave - select the best available slave to be the active one
751  * @bond: our bonding struct
752  */
753 static struct slave *bond_find_best_slave(struct bonding *bond)
754 {
755 	struct slave *slave, *bestslave = NULL;
756 	struct list_head *iter;
757 	int mintime = bond->params.updelay;
758 
759 	slave = bond_choose_primary_or_current(bond);
760 	if (slave)
761 		return slave;
762 
763 	bond_for_each_slave(bond, slave, iter) {
764 		if (slave->link == BOND_LINK_UP)
765 			return slave;
766 		if (slave->link == BOND_LINK_BACK && bond_slave_is_up(slave) &&
767 		    slave->delay < mintime) {
768 			mintime = slave->delay;
769 			bestslave = slave;
770 		}
771 	}
772 
773 	return bestslave;
774 }
775 
776 static bool bond_should_notify_peers(struct bonding *bond)
777 {
778 	struct slave *slave;
779 
780 	rcu_read_lock();
781 	slave = rcu_dereference(bond->curr_active_slave);
782 	rcu_read_unlock();
783 
784 	netdev_dbg(bond->dev, "bond_should_notify_peers: slave %s\n",
785 		   slave ? slave->dev->name : "NULL");
786 
787 	if (!slave || !bond->send_peer_notif ||
788 	    !netif_carrier_ok(bond->dev) ||
789 	    test_bit(__LINK_STATE_LINKWATCH_PENDING, &slave->dev->state))
790 		return false;
791 
792 	return true;
793 }
794 
795 /**
796  * change_active_interface - change the active slave into the specified one
797  * @bond: our bonding struct
798  * @new: the new slave to make the active one
799  *
800  * Set the new slave to the bond's settings and unset them on the old
801  * curr_active_slave.
802  * Setting include flags, mc-list, promiscuity, allmulti, etc.
803  *
804  * If @new's link state is %BOND_LINK_BACK we'll set it to %BOND_LINK_UP,
805  * because it is apparently the best available slave we have, even though its
806  * updelay hasn't timed out yet.
807  *
808  * Caller must hold RTNL.
809  */
810 void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
811 {
812 	struct slave *old_active;
813 
814 	ASSERT_RTNL();
815 
816 	old_active = rtnl_dereference(bond->curr_active_slave);
817 
818 	if (old_active == new_active)
819 		return;
820 
821 	if (new_active) {
822 		new_active->last_link_up = jiffies;
823 
824 		if (new_active->link == BOND_LINK_BACK) {
825 			if (bond_uses_primary(bond)) {
826 				netdev_info(bond->dev, "making interface %s the new active one %d ms earlier\n",
827 					    new_active->dev->name,
828 					    (bond->params.updelay - new_active->delay) * bond->params.miimon);
829 			}
830 
831 			new_active->delay = 0;
832 			bond_set_slave_link_state(new_active, BOND_LINK_UP,
833 						  BOND_SLAVE_NOTIFY_NOW);
834 
835 			if (BOND_MODE(bond) == BOND_MODE_8023AD)
836 				bond_3ad_handle_link_change(new_active, BOND_LINK_UP);
837 
838 			if (bond_is_lb(bond))
839 				bond_alb_handle_link_change(bond, new_active, BOND_LINK_UP);
840 		} else {
841 			if (bond_uses_primary(bond)) {
842 				netdev_info(bond->dev, "making interface %s the new active one\n",
843 					    new_active->dev->name);
844 			}
845 		}
846 	}
847 
848 	if (bond_uses_primary(bond))
849 		bond_hw_addr_swap(bond, new_active, old_active);
850 
851 	if (bond_is_lb(bond)) {
852 		bond_alb_handle_active_change(bond, new_active);
853 		if (old_active)
854 			bond_set_slave_inactive_flags(old_active,
855 						      BOND_SLAVE_NOTIFY_NOW);
856 		if (new_active)
857 			bond_set_slave_active_flags(new_active,
858 						    BOND_SLAVE_NOTIFY_NOW);
859 	} else {
860 		rcu_assign_pointer(bond->curr_active_slave, new_active);
861 	}
862 
863 	if (BOND_MODE(bond) == BOND_MODE_ACTIVEBACKUP) {
864 		if (old_active)
865 			bond_set_slave_inactive_flags(old_active,
866 						      BOND_SLAVE_NOTIFY_NOW);
867 
868 		if (new_active) {
869 			bool should_notify_peers = false;
870 
871 			bond_set_slave_active_flags(new_active,
872 						    BOND_SLAVE_NOTIFY_NOW);
873 
874 			if (bond->params.fail_over_mac)
875 				bond_do_fail_over_mac(bond, new_active,
876 						      old_active);
877 
878 			if (netif_running(bond->dev)) {
879 				bond->send_peer_notif =
880 					bond->params.num_peer_notif;
881 				should_notify_peers =
882 					bond_should_notify_peers(bond);
883 			}
884 
885 			call_netdevice_notifiers(NETDEV_BONDING_FAILOVER, bond->dev);
886 			if (should_notify_peers)
887 				call_netdevice_notifiers(NETDEV_NOTIFY_PEERS,
888 							 bond->dev);
889 		}
890 	}
891 
892 	/* resend IGMP joins since active slave has changed or
893 	 * all were sent on curr_active_slave.
894 	 * resend only if bond is brought up with the affected
895 	 * bonding modes and the retransmission is enabled
896 	 */
897 	if (netif_running(bond->dev) && (bond->params.resend_igmp > 0) &&
898 	    ((bond_uses_primary(bond) && new_active) ||
899 	     BOND_MODE(bond) == BOND_MODE_ROUNDROBIN)) {
900 		bond->igmp_retrans = bond->params.resend_igmp;
901 		queue_delayed_work(bond->wq, &bond->mcast_work, 1);
902 	}
903 }
904 
905 /**
906  * bond_select_active_slave - select a new active slave, if needed
907  * @bond: our bonding struct
908  *
909  * This functions should be called when one of the following occurs:
910  * - The old curr_active_slave has been released or lost its link.
911  * - The primary_slave has got its link back.
912  * - A slave has got its link back and there's no old curr_active_slave.
913  *
914  * Caller must hold RTNL.
915  */
916 void bond_select_active_slave(struct bonding *bond)
917 {
918 	struct slave *best_slave;
919 	int rv;
920 
921 	ASSERT_RTNL();
922 
923 	best_slave = bond_find_best_slave(bond);
924 	if (best_slave != rtnl_dereference(bond->curr_active_slave)) {
925 		bond_change_active_slave(bond, best_slave);
926 		rv = bond_set_carrier(bond);
927 		if (!rv)
928 			return;
929 
930 		if (netif_carrier_ok(bond->dev))
931 			netdev_info(bond->dev, "first active interface up!\n");
932 		else
933 			netdev_info(bond->dev, "now running without any active interface!\n");
934 	}
935 }
936 
937 #ifdef CONFIG_NET_POLL_CONTROLLER
938 static inline int slave_enable_netpoll(struct slave *slave)
939 {
940 	struct netpoll *np;
941 	int err = 0;
942 
943 	np = kzalloc(sizeof(*np), GFP_KERNEL);
944 	err = -ENOMEM;
945 	if (!np)
946 		goto out;
947 
948 	err = __netpoll_setup(np, slave->dev);
949 	if (err) {
950 		kfree(np);
951 		goto out;
952 	}
953 	slave->np = np;
954 out:
955 	return err;
956 }
957 static inline void slave_disable_netpoll(struct slave *slave)
958 {
959 	struct netpoll *np = slave->np;
960 
961 	if (!np)
962 		return;
963 
964 	slave->np = NULL;
965 	__netpoll_free_async(np);
966 }
967 
968 static void bond_poll_controller(struct net_device *bond_dev)
969 {
970 	struct bonding *bond = netdev_priv(bond_dev);
971 	struct slave *slave = NULL;
972 	struct list_head *iter;
973 	struct ad_info ad_info;
974 	struct netpoll_info *ni;
975 	const struct net_device_ops *ops;
976 
977 	if (BOND_MODE(bond) == BOND_MODE_8023AD)
978 		if (bond_3ad_get_active_agg_info(bond, &ad_info))
979 			return;
980 
981 	bond_for_each_slave_rcu(bond, slave, iter) {
982 		ops = slave->dev->netdev_ops;
983 		if (!bond_slave_is_up(slave) || !ops->ndo_poll_controller)
984 			continue;
985 
986 		if (BOND_MODE(bond) == BOND_MODE_8023AD) {
987 			struct aggregator *agg =
988 			    SLAVE_AD_INFO(slave)->port.aggregator;
989 
990 			if (agg &&
991 			    agg->aggregator_identifier != ad_info.aggregator_id)
992 				continue;
993 		}
994 
995 		ni = rcu_dereference_bh(slave->dev->npinfo);
996 		if (down_trylock(&ni->dev_lock))
997 			continue;
998 		ops->ndo_poll_controller(slave->dev);
999 		up(&ni->dev_lock);
1000 	}
1001 }
1002 
1003 static void bond_netpoll_cleanup(struct net_device *bond_dev)
1004 {
1005 	struct bonding *bond = netdev_priv(bond_dev);
1006 	struct list_head *iter;
1007 	struct slave *slave;
1008 
1009 	bond_for_each_slave(bond, slave, iter)
1010 		if (bond_slave_is_up(slave))
1011 			slave_disable_netpoll(slave);
1012 }
1013 
1014 static int bond_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
1015 {
1016 	struct bonding *bond = netdev_priv(dev);
1017 	struct list_head *iter;
1018 	struct slave *slave;
1019 	int err = 0;
1020 
1021 	bond_for_each_slave(bond, slave, iter) {
1022 		err = slave_enable_netpoll(slave);
1023 		if (err) {
1024 			bond_netpoll_cleanup(dev);
1025 			break;
1026 		}
1027 	}
1028 	return err;
1029 }
1030 #else
1031 static inline int slave_enable_netpoll(struct slave *slave)
1032 {
1033 	return 0;
1034 }
1035 static inline void slave_disable_netpoll(struct slave *slave)
1036 {
1037 }
1038 static void bond_netpoll_cleanup(struct net_device *bond_dev)
1039 {
1040 }
1041 #endif
1042 
1043 /*---------------------------------- IOCTL ----------------------------------*/
1044 
1045 static netdev_features_t bond_fix_features(struct net_device *dev,
1046 					   netdev_features_t features)
1047 {
1048 	struct bonding *bond = netdev_priv(dev);
1049 	struct list_head *iter;
1050 	netdev_features_t mask;
1051 	struct slave *slave;
1052 
1053 	mask = features;
1054 
1055 	features &= ~NETIF_F_ONE_FOR_ALL;
1056 	features |= NETIF_F_ALL_FOR_ALL;
1057 
1058 	bond_for_each_slave(bond, slave, iter) {
1059 		features = netdev_increment_features(features,
1060 						     slave->dev->features,
1061 						     mask);
1062 	}
1063 	features = netdev_add_tso_features(features, mask);
1064 
1065 	return features;
1066 }
1067 
1068 #define BOND_VLAN_FEATURES	(NETIF_F_HW_CSUM | NETIF_F_SG | \
1069 				 NETIF_F_FRAGLIST | NETIF_F_ALL_TSO | \
1070 				 NETIF_F_HIGHDMA | NETIF_F_LRO)
1071 
1072 #define BOND_ENC_FEATURES	(NETIF_F_HW_CSUM | NETIF_F_SG | \
1073 				 NETIF_F_RXCSUM | NETIF_F_ALL_TSO)
1074 
1075 static void bond_compute_features(struct bonding *bond)
1076 {
1077 	unsigned int dst_release_flag = IFF_XMIT_DST_RELEASE |
1078 					IFF_XMIT_DST_RELEASE_PERM;
1079 	netdev_features_t vlan_features = BOND_VLAN_FEATURES;
1080 	netdev_features_t enc_features  = BOND_ENC_FEATURES;
1081 	struct net_device *bond_dev = bond->dev;
1082 	struct list_head *iter;
1083 	struct slave *slave;
1084 	unsigned short max_hard_header_len = ETH_HLEN;
1085 	unsigned int gso_max_size = GSO_MAX_SIZE;
1086 	u16 gso_max_segs = GSO_MAX_SEGS;
1087 
1088 	if (!bond_has_slaves(bond))
1089 		goto done;
1090 	vlan_features &= NETIF_F_ALL_FOR_ALL;
1091 
1092 	bond_for_each_slave(bond, slave, iter) {
1093 		vlan_features = netdev_increment_features(vlan_features,
1094 			slave->dev->vlan_features, BOND_VLAN_FEATURES);
1095 
1096 		enc_features = netdev_increment_features(enc_features,
1097 							 slave->dev->hw_enc_features,
1098 							 BOND_ENC_FEATURES);
1099 		dst_release_flag &= slave->dev->priv_flags;
1100 		if (slave->dev->hard_header_len > max_hard_header_len)
1101 			max_hard_header_len = slave->dev->hard_header_len;
1102 
1103 		gso_max_size = min(gso_max_size, slave->dev->gso_max_size);
1104 		gso_max_segs = min(gso_max_segs, slave->dev->gso_max_segs);
1105 	}
1106 	bond_dev->hard_header_len = max_hard_header_len;
1107 
1108 done:
1109 	bond_dev->vlan_features = vlan_features;
1110 	bond_dev->hw_enc_features = enc_features | NETIF_F_GSO_ENCAP_ALL;
1111 	bond_dev->gso_max_segs = gso_max_segs;
1112 	netif_set_gso_max_size(bond_dev, gso_max_size);
1113 
1114 	bond_dev->priv_flags &= ~IFF_XMIT_DST_RELEASE;
1115 	if ((bond_dev->priv_flags & IFF_XMIT_DST_RELEASE_PERM) &&
1116 	    dst_release_flag == (IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM))
1117 		bond_dev->priv_flags |= IFF_XMIT_DST_RELEASE;
1118 
1119 	netdev_change_features(bond_dev);
1120 }
1121 
1122 static void bond_setup_by_slave(struct net_device *bond_dev,
1123 				struct net_device *slave_dev)
1124 {
1125 	bond_dev->header_ops	    = slave_dev->header_ops;
1126 
1127 	bond_dev->type		    = slave_dev->type;
1128 	bond_dev->hard_header_len   = slave_dev->hard_header_len;
1129 	bond_dev->addr_len	    = slave_dev->addr_len;
1130 
1131 	memcpy(bond_dev->broadcast, slave_dev->broadcast,
1132 		slave_dev->addr_len);
1133 }
1134 
1135 /* On bonding slaves other than the currently active slave, suppress
1136  * duplicates except for alb non-mcast/bcast.
1137  */
1138 static bool bond_should_deliver_exact_match(struct sk_buff *skb,
1139 					    struct slave *slave,
1140 					    struct bonding *bond)
1141 {
1142 	if (bond_is_slave_inactive(slave)) {
1143 		if (BOND_MODE(bond) == BOND_MODE_ALB &&
1144 		    skb->pkt_type != PACKET_BROADCAST &&
1145 		    skb->pkt_type != PACKET_MULTICAST)
1146 			return false;
1147 		return true;
1148 	}
1149 	return false;
1150 }
1151 
1152 static rx_handler_result_t bond_handle_frame(struct sk_buff **pskb)
1153 {
1154 	struct sk_buff *skb = *pskb;
1155 	struct slave *slave;
1156 	struct bonding *bond;
1157 	int (*recv_probe)(const struct sk_buff *, struct bonding *,
1158 			  struct slave *);
1159 	int ret = RX_HANDLER_ANOTHER;
1160 
1161 	skb = skb_share_check(skb, GFP_ATOMIC);
1162 	if (unlikely(!skb))
1163 		return RX_HANDLER_CONSUMED;
1164 
1165 	*pskb = skb;
1166 
1167 	slave = bond_slave_get_rcu(skb->dev);
1168 	bond = slave->bond;
1169 
1170 	recv_probe = READ_ONCE(bond->recv_probe);
1171 	if (recv_probe) {
1172 		ret = recv_probe(skb, bond, slave);
1173 		if (ret == RX_HANDLER_CONSUMED) {
1174 			consume_skb(skb);
1175 			return ret;
1176 		}
1177 	}
1178 
1179 	/* don't change skb->dev for link-local packets */
1180 	if (is_link_local_ether_addr(eth_hdr(skb)->h_dest))
1181 		return RX_HANDLER_PASS;
1182 	if (bond_should_deliver_exact_match(skb, slave, bond))
1183 		return RX_HANDLER_EXACT;
1184 
1185 	skb->dev = bond->dev;
1186 
1187 	if (BOND_MODE(bond) == BOND_MODE_ALB &&
1188 	    bond->dev->priv_flags & IFF_BRIDGE_PORT &&
1189 	    skb->pkt_type == PACKET_HOST) {
1190 
1191 		if (unlikely(skb_cow_head(skb,
1192 					  skb->data - skb_mac_header(skb)))) {
1193 			kfree_skb(skb);
1194 			return RX_HANDLER_CONSUMED;
1195 		}
1196 		bond_hw_addr_copy(eth_hdr(skb)->h_dest, bond->dev->dev_addr,
1197 				  bond->dev->addr_len);
1198 	}
1199 
1200 	return ret;
1201 }
1202 
1203 static enum netdev_lag_tx_type bond_lag_tx_type(struct bonding *bond)
1204 {
1205 	switch (BOND_MODE(bond)) {
1206 	case BOND_MODE_ROUNDROBIN:
1207 		return NETDEV_LAG_TX_TYPE_ROUNDROBIN;
1208 	case BOND_MODE_ACTIVEBACKUP:
1209 		return NETDEV_LAG_TX_TYPE_ACTIVEBACKUP;
1210 	case BOND_MODE_BROADCAST:
1211 		return NETDEV_LAG_TX_TYPE_BROADCAST;
1212 	case BOND_MODE_XOR:
1213 	case BOND_MODE_8023AD:
1214 		return NETDEV_LAG_TX_TYPE_HASH;
1215 	default:
1216 		return NETDEV_LAG_TX_TYPE_UNKNOWN;
1217 	}
1218 }
1219 
1220 static int bond_master_upper_dev_link(struct bonding *bond, struct slave *slave)
1221 {
1222 	struct netdev_lag_upper_info lag_upper_info;
1223 	int err;
1224 
1225 	lag_upper_info.tx_type = bond_lag_tx_type(bond);
1226 	err = netdev_master_upper_dev_link(slave->dev, bond->dev, slave,
1227 					   &lag_upper_info);
1228 	if (err)
1229 		return err;
1230 	rtmsg_ifinfo(RTM_NEWLINK, slave->dev, IFF_SLAVE, GFP_KERNEL);
1231 	return 0;
1232 }
1233 
1234 static void bond_upper_dev_unlink(struct bonding *bond, struct slave *slave)
1235 {
1236 	netdev_upper_dev_unlink(slave->dev, bond->dev);
1237 	slave->dev->flags &= ~IFF_SLAVE;
1238 	rtmsg_ifinfo(RTM_NEWLINK, slave->dev, IFF_SLAVE, GFP_KERNEL);
1239 }
1240 
1241 static struct slave *bond_alloc_slave(struct bonding *bond)
1242 {
1243 	struct slave *slave = NULL;
1244 
1245 	slave = kzalloc(sizeof(*slave), GFP_KERNEL);
1246 	if (!slave)
1247 		return NULL;
1248 
1249 	if (BOND_MODE(bond) == BOND_MODE_8023AD) {
1250 		SLAVE_AD_INFO(slave) = kzalloc(sizeof(struct ad_slave_info),
1251 					       GFP_KERNEL);
1252 		if (!SLAVE_AD_INFO(slave)) {
1253 			kfree(slave);
1254 			return NULL;
1255 		}
1256 	}
1257 	return slave;
1258 }
1259 
1260 static void bond_free_slave(struct slave *slave)
1261 {
1262 	struct bonding *bond = bond_get_bond_by_slave(slave);
1263 
1264 	if (BOND_MODE(bond) == BOND_MODE_8023AD)
1265 		kfree(SLAVE_AD_INFO(slave));
1266 
1267 	kfree(slave);
1268 }
1269 
1270 static void bond_fill_ifbond(struct bonding *bond, struct ifbond *info)
1271 {
1272 	info->bond_mode = BOND_MODE(bond);
1273 	info->miimon = bond->params.miimon;
1274 	info->num_slaves = bond->slave_cnt;
1275 }
1276 
1277 static void bond_fill_ifslave(struct slave *slave, struct ifslave *info)
1278 {
1279 	strcpy(info->slave_name, slave->dev->name);
1280 	info->link = slave->link;
1281 	info->state = bond_slave_state(slave);
1282 	info->link_failure_count = slave->link_failure_count;
1283 }
1284 
1285 static void bond_netdev_notify(struct net_device *dev,
1286 			       struct netdev_bonding_info *info)
1287 {
1288 	rtnl_lock();
1289 	netdev_bonding_info_change(dev, info);
1290 	rtnl_unlock();
1291 }
1292 
1293 static void bond_netdev_notify_work(struct work_struct *_work)
1294 {
1295 	struct netdev_notify_work *w =
1296 		container_of(_work, struct netdev_notify_work, work.work);
1297 
1298 	bond_netdev_notify(w->dev, &w->bonding_info);
1299 	dev_put(w->dev);
1300 	kfree(w);
1301 }
1302 
1303 void bond_queue_slave_event(struct slave *slave)
1304 {
1305 	struct bonding *bond = slave->bond;
1306 	struct netdev_notify_work *nnw = kzalloc(sizeof(*nnw), GFP_ATOMIC);
1307 
1308 	if (!nnw)
1309 		return;
1310 
1311 	dev_hold(slave->dev);
1312 	nnw->dev = slave->dev;
1313 	bond_fill_ifslave(slave, &nnw->bonding_info.slave);
1314 	bond_fill_ifbond(bond, &nnw->bonding_info.master);
1315 	INIT_DELAYED_WORK(&nnw->work, bond_netdev_notify_work);
1316 
1317 	queue_delayed_work(slave->bond->wq, &nnw->work, 0);
1318 }
1319 
1320 void bond_lower_state_changed(struct slave *slave)
1321 {
1322 	struct netdev_lag_lower_state_info info;
1323 
1324 	info.link_up = slave->link == BOND_LINK_UP ||
1325 		       slave->link == BOND_LINK_FAIL;
1326 	info.tx_enabled = bond_is_active_slave(slave);
1327 	netdev_lower_state_changed(slave->dev, &info);
1328 }
1329 
1330 /* enslave device <slave> to bond device <master> */
1331 int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
1332 {
1333 	struct bonding *bond = netdev_priv(bond_dev);
1334 	const struct net_device_ops *slave_ops = slave_dev->netdev_ops;
1335 	struct slave *new_slave = NULL, *prev_slave;
1336 	struct sockaddr_storage ss;
1337 	int link_reporting;
1338 	int res = 0, i;
1339 
1340 	if (!bond->params.use_carrier &&
1341 	    slave_dev->ethtool_ops->get_link == NULL &&
1342 	    slave_ops->ndo_do_ioctl == NULL) {
1343 		netdev_warn(bond_dev, "no link monitoring support for %s\n",
1344 			    slave_dev->name);
1345 	}
1346 
1347 	/* already in-use? */
1348 	if (netdev_is_rx_handler_busy(slave_dev)) {
1349 		netdev_err(bond_dev,
1350 			   "Error: Device is in use and cannot be enslaved\n");
1351 		return -EBUSY;
1352 	}
1353 
1354 	if (bond_dev == slave_dev) {
1355 		netdev_err(bond_dev, "cannot enslave bond to itself.\n");
1356 		return -EPERM;
1357 	}
1358 
1359 	/* vlan challenged mutual exclusion */
1360 	/* no need to lock since we're protected by rtnl_lock */
1361 	if (slave_dev->features & NETIF_F_VLAN_CHALLENGED) {
1362 		netdev_dbg(bond_dev, "%s is NETIF_F_VLAN_CHALLENGED\n",
1363 			   slave_dev->name);
1364 		if (vlan_uses_dev(bond_dev)) {
1365 			netdev_err(bond_dev, "Error: cannot enslave VLAN challenged slave %s on VLAN enabled bond %s\n",
1366 				   slave_dev->name, bond_dev->name);
1367 			return -EPERM;
1368 		} else {
1369 			netdev_warn(bond_dev, "enslaved VLAN challenged slave %s. Adding VLANs will be blocked as long as %s is part of bond %s\n",
1370 				    slave_dev->name, slave_dev->name,
1371 				    bond_dev->name);
1372 		}
1373 	} else {
1374 		netdev_dbg(bond_dev, "%s is !NETIF_F_VLAN_CHALLENGED\n",
1375 			   slave_dev->name);
1376 	}
1377 
1378 	/* Old ifenslave binaries are no longer supported.  These can
1379 	 * be identified with moderate accuracy by the state of the slave:
1380 	 * the current ifenslave will set the interface down prior to
1381 	 * enslaving it; the old ifenslave will not.
1382 	 */
1383 	if (slave_dev->flags & IFF_UP) {
1384 		netdev_err(bond_dev, "%s is up - this may be due to an out of date ifenslave\n",
1385 			   slave_dev->name);
1386 		return -EPERM;
1387 	}
1388 
1389 	/* set bonding device ether type by slave - bonding netdevices are
1390 	 * created with ether_setup, so when the slave type is not ARPHRD_ETHER
1391 	 * there is a need to override some of the type dependent attribs/funcs.
1392 	 *
1393 	 * bond ether type mutual exclusion - don't allow slaves of dissimilar
1394 	 * ether type (eg ARPHRD_ETHER and ARPHRD_INFINIBAND) share the same bond
1395 	 */
1396 	if (!bond_has_slaves(bond)) {
1397 		if (bond_dev->type != slave_dev->type) {
1398 			netdev_dbg(bond_dev, "change device type from %d to %d\n",
1399 				   bond_dev->type, slave_dev->type);
1400 
1401 			res = call_netdevice_notifiers(NETDEV_PRE_TYPE_CHANGE,
1402 						       bond_dev);
1403 			res = notifier_to_errno(res);
1404 			if (res) {
1405 				netdev_err(bond_dev, "refused to change device type\n");
1406 				return -EBUSY;
1407 			}
1408 
1409 			/* Flush unicast and multicast addresses */
1410 			dev_uc_flush(bond_dev);
1411 			dev_mc_flush(bond_dev);
1412 
1413 			if (slave_dev->type != ARPHRD_ETHER)
1414 				bond_setup_by_slave(bond_dev, slave_dev);
1415 			else {
1416 				ether_setup(bond_dev);
1417 				bond_dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1418 			}
1419 
1420 			call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE,
1421 						 bond_dev);
1422 		}
1423 	} else if (bond_dev->type != slave_dev->type) {
1424 		netdev_err(bond_dev, "%s ether type (%d) is different from other slaves (%d), can not enslave it\n",
1425 			   slave_dev->name, slave_dev->type, bond_dev->type);
1426 		return -EINVAL;
1427 	}
1428 
1429 	if (slave_dev->type == ARPHRD_INFINIBAND &&
1430 	    BOND_MODE(bond) != BOND_MODE_ACTIVEBACKUP) {
1431 		netdev_warn(bond_dev, "Type (%d) supports only active-backup mode\n",
1432 			    slave_dev->type);
1433 		res = -EOPNOTSUPP;
1434 		goto err_undo_flags;
1435 	}
1436 
1437 	if (!slave_ops->ndo_set_mac_address ||
1438 	    slave_dev->type == ARPHRD_INFINIBAND) {
1439 		netdev_warn(bond_dev, "The slave device specified does not support setting the MAC address\n");
1440 		if (BOND_MODE(bond) == BOND_MODE_ACTIVEBACKUP &&
1441 		    bond->params.fail_over_mac != BOND_FOM_ACTIVE) {
1442 			if (!bond_has_slaves(bond)) {
1443 				bond->params.fail_over_mac = BOND_FOM_ACTIVE;
1444 				netdev_warn(bond_dev, "Setting fail_over_mac to active for active-backup mode\n");
1445 			} else {
1446 				netdev_err(bond_dev, "The slave device specified does not support setting the MAC address, but fail_over_mac is not set to active\n");
1447 				res = -EOPNOTSUPP;
1448 				goto err_undo_flags;
1449 			}
1450 		}
1451 	}
1452 
1453 	call_netdevice_notifiers(NETDEV_JOIN, slave_dev);
1454 
1455 	/* If this is the first slave, then we need to set the master's hardware
1456 	 * address to be the same as the slave's.
1457 	 */
1458 	if (!bond_has_slaves(bond) &&
1459 	    bond->dev->addr_assign_type == NET_ADDR_RANDOM)
1460 		bond_set_dev_addr(bond->dev, slave_dev);
1461 
1462 	new_slave = bond_alloc_slave(bond);
1463 	if (!new_slave) {
1464 		res = -ENOMEM;
1465 		goto err_undo_flags;
1466 	}
1467 
1468 	new_slave->bond = bond;
1469 	new_slave->dev = slave_dev;
1470 	/* Set the new_slave's queue_id to be zero.  Queue ID mapping
1471 	 * is set via sysfs or module option if desired.
1472 	 */
1473 	new_slave->queue_id = 0;
1474 
1475 	/* Save slave's original mtu and then set it to match the bond */
1476 	new_slave->original_mtu = slave_dev->mtu;
1477 	res = dev_set_mtu(slave_dev, bond->dev->mtu);
1478 	if (res) {
1479 		netdev_dbg(bond_dev, "Error %d calling dev_set_mtu\n", res);
1480 		goto err_free;
1481 	}
1482 
1483 	/* Save slave's original ("permanent") mac address for modes
1484 	 * that need it, and for restoring it upon release, and then
1485 	 * set it to the master's address
1486 	 */
1487 	bond_hw_addr_copy(new_slave->perm_hwaddr, slave_dev->dev_addr,
1488 			  slave_dev->addr_len);
1489 
1490 	if (!bond->params.fail_over_mac ||
1491 	    BOND_MODE(bond) != BOND_MODE_ACTIVEBACKUP) {
1492 		/* Set slave to master's mac address.  The application already
1493 		 * set the master's mac address to that of the first slave
1494 		 */
1495 		memcpy(ss.__data, bond_dev->dev_addr, bond_dev->addr_len);
1496 		ss.ss_family = slave_dev->type;
1497 		res = dev_set_mac_address(slave_dev, (struct sockaddr *)&ss);
1498 		if (res) {
1499 			netdev_dbg(bond_dev, "Error %d calling set_mac_address\n", res);
1500 			goto err_restore_mtu;
1501 		}
1502 	}
1503 
1504 	/* set slave flag before open to prevent IPv6 addrconf */
1505 	slave_dev->flags |= IFF_SLAVE;
1506 
1507 	/* open the slave since the application closed it */
1508 	res = dev_open(slave_dev);
1509 	if (res) {
1510 		netdev_dbg(bond_dev, "Opening slave %s failed\n", slave_dev->name);
1511 		goto err_restore_mac;
1512 	}
1513 
1514 	slave_dev->priv_flags |= IFF_BONDING;
1515 	/* initialize slave stats */
1516 	dev_get_stats(new_slave->dev, &new_slave->slave_stats);
1517 
1518 	if (bond_is_lb(bond)) {
1519 		/* bond_alb_init_slave() must be called before all other stages since
1520 		 * it might fail and we do not want to have to undo everything
1521 		 */
1522 		res = bond_alb_init_slave(bond, new_slave);
1523 		if (res)
1524 			goto err_close;
1525 	}
1526 
1527 	/* If the mode uses primary, then the following is handled by
1528 	 * bond_change_active_slave().
1529 	 */
1530 	if (!bond_uses_primary(bond)) {
1531 		/* set promiscuity level to new slave */
1532 		if (bond_dev->flags & IFF_PROMISC) {
1533 			res = dev_set_promiscuity(slave_dev, 1);
1534 			if (res)
1535 				goto err_close;
1536 		}
1537 
1538 		/* set allmulti level to new slave */
1539 		if (bond_dev->flags & IFF_ALLMULTI) {
1540 			res = dev_set_allmulti(slave_dev, 1);
1541 			if (res)
1542 				goto err_close;
1543 		}
1544 
1545 		netif_addr_lock_bh(bond_dev);
1546 
1547 		dev_mc_sync_multiple(slave_dev, bond_dev);
1548 		dev_uc_sync_multiple(slave_dev, bond_dev);
1549 
1550 		netif_addr_unlock_bh(bond_dev);
1551 	}
1552 
1553 	if (BOND_MODE(bond) == BOND_MODE_8023AD) {
1554 		/* add lacpdu mc addr to mc list */
1555 		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
1556 
1557 		dev_mc_add(slave_dev, lacpdu_multicast);
1558 	}
1559 
1560 	res = vlan_vids_add_by_dev(slave_dev, bond_dev);
1561 	if (res) {
1562 		netdev_err(bond_dev, "Couldn't add bond vlan ids to %s\n",
1563 			   slave_dev->name);
1564 		goto err_close;
1565 	}
1566 
1567 	prev_slave = bond_last_slave(bond);
1568 
1569 	new_slave->delay = 0;
1570 	new_slave->link_failure_count = 0;
1571 
1572 	if (bond_update_speed_duplex(new_slave) &&
1573 	    bond_needs_speed_duplex(bond))
1574 		new_slave->link = BOND_LINK_DOWN;
1575 
1576 	new_slave->last_rx = jiffies -
1577 		(msecs_to_jiffies(bond->params.arp_interval) + 1);
1578 	for (i = 0; i < BOND_MAX_ARP_TARGETS; i++)
1579 		new_slave->target_last_arp_rx[i] = new_slave->last_rx;
1580 
1581 	if (bond->params.miimon && !bond->params.use_carrier) {
1582 		link_reporting = bond_check_dev_link(bond, slave_dev, 1);
1583 
1584 		if ((link_reporting == -1) && !bond->params.arp_interval) {
1585 			/* miimon is set but a bonded network driver
1586 			 * does not support ETHTOOL/MII and
1587 			 * arp_interval is not set.  Note: if
1588 			 * use_carrier is enabled, we will never go
1589 			 * here (because netif_carrier is always
1590 			 * supported); thus, we don't need to change
1591 			 * the messages for netif_carrier.
1592 			 */
1593 			netdev_warn(bond_dev, "MII and ETHTOOL support not available for interface %s, and arp_interval/arp_ip_target module parameters not specified, thus bonding will not detect link failures! see bonding.txt for details\n",
1594 				    slave_dev->name);
1595 		} else if (link_reporting == -1) {
1596 			/* unable get link status using mii/ethtool */
1597 			netdev_warn(bond_dev, "can't get link status from interface %s; the network driver associated with this interface does not support MII or ETHTOOL link status reporting, thus miimon has no effect on this interface\n",
1598 				    slave_dev->name);
1599 		}
1600 	}
1601 
1602 	/* check for initial state */
1603 	new_slave->link = BOND_LINK_NOCHANGE;
1604 	if (bond->params.miimon) {
1605 		if (bond_check_dev_link(bond, slave_dev, 0) == BMSR_LSTATUS) {
1606 			if (bond->params.updelay) {
1607 				bond_set_slave_link_state(new_slave,
1608 							  BOND_LINK_BACK,
1609 							  BOND_SLAVE_NOTIFY_NOW);
1610 				new_slave->delay = bond->params.updelay;
1611 			} else {
1612 				bond_set_slave_link_state(new_slave,
1613 							  BOND_LINK_UP,
1614 							  BOND_SLAVE_NOTIFY_NOW);
1615 			}
1616 		} else {
1617 			bond_set_slave_link_state(new_slave, BOND_LINK_DOWN,
1618 						  BOND_SLAVE_NOTIFY_NOW);
1619 		}
1620 	} else if (bond->params.arp_interval) {
1621 		bond_set_slave_link_state(new_slave,
1622 					  (netif_carrier_ok(slave_dev) ?
1623 					  BOND_LINK_UP : BOND_LINK_DOWN),
1624 					  BOND_SLAVE_NOTIFY_NOW);
1625 	} else {
1626 		bond_set_slave_link_state(new_slave, BOND_LINK_UP,
1627 					  BOND_SLAVE_NOTIFY_NOW);
1628 	}
1629 
1630 	if (new_slave->link != BOND_LINK_DOWN)
1631 		new_slave->last_link_up = jiffies;
1632 	netdev_dbg(bond_dev, "Initial state of slave_dev is BOND_LINK_%s\n",
1633 		   new_slave->link == BOND_LINK_DOWN ? "DOWN" :
1634 		   (new_slave->link == BOND_LINK_UP ? "UP" : "BACK"));
1635 
1636 	if (bond_uses_primary(bond) && bond->params.primary[0]) {
1637 		/* if there is a primary slave, remember it */
1638 		if (strcmp(bond->params.primary, new_slave->dev->name) == 0) {
1639 			rcu_assign_pointer(bond->primary_slave, new_slave);
1640 			bond->force_primary = true;
1641 		}
1642 	}
1643 
1644 	switch (BOND_MODE(bond)) {
1645 	case BOND_MODE_ACTIVEBACKUP:
1646 		bond_set_slave_inactive_flags(new_slave,
1647 					      BOND_SLAVE_NOTIFY_NOW);
1648 		break;
1649 	case BOND_MODE_8023AD:
1650 		/* in 802.3ad mode, the internal mechanism
1651 		 * will activate the slaves in the selected
1652 		 * aggregator
1653 		 */
1654 		bond_set_slave_inactive_flags(new_slave, BOND_SLAVE_NOTIFY_NOW);
1655 		/* if this is the first slave */
1656 		if (!prev_slave) {
1657 			SLAVE_AD_INFO(new_slave)->id = 1;
1658 			/* Initialize AD with the number of times that the AD timer is called in 1 second
1659 			 * can be called only after the mac address of the bond is set
1660 			 */
1661 			bond_3ad_initialize(bond, 1000/AD_TIMER_INTERVAL);
1662 		} else {
1663 			SLAVE_AD_INFO(new_slave)->id =
1664 				SLAVE_AD_INFO(prev_slave)->id + 1;
1665 		}
1666 
1667 		bond_3ad_bind_slave(new_slave);
1668 		break;
1669 	case BOND_MODE_TLB:
1670 	case BOND_MODE_ALB:
1671 		bond_set_active_slave(new_slave);
1672 		bond_set_slave_inactive_flags(new_slave, BOND_SLAVE_NOTIFY_NOW);
1673 		break;
1674 	default:
1675 		netdev_dbg(bond_dev, "This slave is always active in trunk mode\n");
1676 
1677 		/* always active in trunk mode */
1678 		bond_set_active_slave(new_slave);
1679 
1680 		/* In trunking mode there is little meaning to curr_active_slave
1681 		 * anyway (it holds no special properties of the bond device),
1682 		 * so we can change it without calling change_active_interface()
1683 		 */
1684 		if (!rcu_access_pointer(bond->curr_active_slave) &&
1685 		    new_slave->link == BOND_LINK_UP)
1686 			rcu_assign_pointer(bond->curr_active_slave, new_slave);
1687 
1688 		break;
1689 	} /* switch(bond_mode) */
1690 
1691 #ifdef CONFIG_NET_POLL_CONTROLLER
1692 	slave_dev->npinfo = bond->dev->npinfo;
1693 	if (slave_dev->npinfo) {
1694 		if (slave_enable_netpoll(new_slave)) {
1695 			netdev_info(bond_dev, "master_dev is using netpoll, but new slave device does not support netpoll\n");
1696 			res = -EBUSY;
1697 			goto err_detach;
1698 		}
1699 	}
1700 #endif
1701 
1702 	if (!(bond_dev->features & NETIF_F_LRO))
1703 		dev_disable_lro(slave_dev);
1704 
1705 	res = netdev_rx_handler_register(slave_dev, bond_handle_frame,
1706 					 new_slave);
1707 	if (res) {
1708 		netdev_dbg(bond_dev, "Error %d calling netdev_rx_handler_register\n", res);
1709 		goto err_detach;
1710 	}
1711 
1712 	res = bond_master_upper_dev_link(bond, new_slave);
1713 	if (res) {
1714 		netdev_dbg(bond_dev, "Error %d calling bond_master_upper_dev_link\n", res);
1715 		goto err_unregister;
1716 	}
1717 
1718 	res = bond_sysfs_slave_add(new_slave);
1719 	if (res) {
1720 		netdev_dbg(bond_dev, "Error %d calling bond_sysfs_slave_add\n", res);
1721 		goto err_upper_unlink;
1722 	}
1723 
1724 	bond->slave_cnt++;
1725 	bond_compute_features(bond);
1726 	bond_set_carrier(bond);
1727 
1728 	if (bond_uses_primary(bond)) {
1729 		block_netpoll_tx();
1730 		bond_select_active_slave(bond);
1731 		unblock_netpoll_tx();
1732 	}
1733 
1734 	if (bond_mode_uses_xmit_hash(bond))
1735 		bond_update_slave_arr(bond, NULL);
1736 
1737 	netdev_info(bond_dev, "Enslaving %s as %s interface with %s link\n",
1738 		    slave_dev->name,
1739 		    bond_is_active_slave(new_slave) ? "an active" : "a backup",
1740 		    new_slave->link != BOND_LINK_DOWN ? "an up" : "a down");
1741 
1742 	/* enslave is successful */
1743 	bond_queue_slave_event(new_slave);
1744 	return 0;
1745 
1746 /* Undo stages on error */
1747 err_upper_unlink:
1748 	bond_upper_dev_unlink(bond, new_slave);
1749 
1750 err_unregister:
1751 	netdev_rx_handler_unregister(slave_dev);
1752 
1753 err_detach:
1754 	if (!bond_uses_primary(bond))
1755 		bond_hw_addr_flush(bond_dev, slave_dev);
1756 
1757 	vlan_vids_del_by_dev(slave_dev, bond_dev);
1758 	if (rcu_access_pointer(bond->primary_slave) == new_slave)
1759 		RCU_INIT_POINTER(bond->primary_slave, NULL);
1760 	if (rcu_access_pointer(bond->curr_active_slave) == new_slave) {
1761 		block_netpoll_tx();
1762 		bond_change_active_slave(bond, NULL);
1763 		bond_select_active_slave(bond);
1764 		unblock_netpoll_tx();
1765 	}
1766 	/* either primary_slave or curr_active_slave might've changed */
1767 	synchronize_rcu();
1768 	slave_disable_netpoll(new_slave);
1769 
1770 err_close:
1771 	slave_dev->priv_flags &= ~IFF_BONDING;
1772 	dev_close(slave_dev);
1773 
1774 err_restore_mac:
1775 	slave_dev->flags &= ~IFF_SLAVE;
1776 	if (!bond->params.fail_over_mac ||
1777 	    BOND_MODE(bond) != BOND_MODE_ACTIVEBACKUP) {
1778 		/* XXX TODO - fom follow mode needs to change master's
1779 		 * MAC if this slave's MAC is in use by the bond, or at
1780 		 * least print a warning.
1781 		 */
1782 		bond_hw_addr_copy(ss.__data, new_slave->perm_hwaddr,
1783 				  new_slave->dev->addr_len);
1784 		ss.ss_family = slave_dev->type;
1785 		dev_set_mac_address(slave_dev, (struct sockaddr *)&ss);
1786 	}
1787 
1788 err_restore_mtu:
1789 	dev_set_mtu(slave_dev, new_slave->original_mtu);
1790 
1791 err_free:
1792 	bond_free_slave(new_slave);
1793 
1794 err_undo_flags:
1795 	/* Enslave of first slave has failed and we need to fix master's mac */
1796 	if (!bond_has_slaves(bond)) {
1797 		if (ether_addr_equal_64bits(bond_dev->dev_addr,
1798 					    slave_dev->dev_addr))
1799 			eth_hw_addr_random(bond_dev);
1800 		if (bond_dev->type != ARPHRD_ETHER) {
1801 			dev_close(bond_dev);
1802 			ether_setup(bond_dev);
1803 			bond_dev->flags |= IFF_MASTER;
1804 			bond_dev->priv_flags &= ~IFF_TX_SKB_SHARING;
1805 		}
1806 	}
1807 
1808 	return res;
1809 }
1810 
1811 /* Try to release the slave device <slave> from the bond device <master>
1812  * It is legal to access curr_active_slave without a lock because all the function
1813  * is RTNL-locked. If "all" is true it means that the function is being called
1814  * while destroying a bond interface and all slaves are being released.
1815  *
1816  * The rules for slave state should be:
1817  *   for Active/Backup:
1818  *     Active stays on all backups go down
1819  *   for Bonded connections:
1820  *     The first up interface should be left on and all others downed.
1821  */
1822 static int __bond_release_one(struct net_device *bond_dev,
1823 			      struct net_device *slave_dev,
1824 			      bool all, bool unregister)
1825 {
1826 	struct bonding *bond = netdev_priv(bond_dev);
1827 	struct slave *slave, *oldcurrent;
1828 	struct sockaddr_storage ss;
1829 	int old_flags = bond_dev->flags;
1830 	netdev_features_t old_features = bond_dev->features;
1831 
1832 	/* slave is not a slave or master is not master of this slave */
1833 	if (!(slave_dev->flags & IFF_SLAVE) ||
1834 	    !netdev_has_upper_dev(slave_dev, bond_dev)) {
1835 		netdev_dbg(bond_dev, "cannot release %s\n",
1836 			   slave_dev->name);
1837 		return -EINVAL;
1838 	}
1839 
1840 	block_netpoll_tx();
1841 
1842 	slave = bond_get_slave_by_dev(bond, slave_dev);
1843 	if (!slave) {
1844 		/* not a slave of this bond */
1845 		netdev_info(bond_dev, "%s not enslaved\n",
1846 			    slave_dev->name);
1847 		unblock_netpoll_tx();
1848 		return -EINVAL;
1849 	}
1850 
1851 	bond_set_slave_inactive_flags(slave, BOND_SLAVE_NOTIFY_NOW);
1852 
1853 	bond_sysfs_slave_del(slave);
1854 
1855 	/* recompute stats just before removing the slave */
1856 	bond_get_stats(bond->dev, &bond->bond_stats);
1857 
1858 	bond_upper_dev_unlink(bond, slave);
1859 	/* unregister rx_handler early so bond_handle_frame wouldn't be called
1860 	 * for this slave anymore.
1861 	 */
1862 	netdev_rx_handler_unregister(slave_dev);
1863 
1864 	if (BOND_MODE(bond) == BOND_MODE_8023AD)
1865 		bond_3ad_unbind_slave(slave);
1866 
1867 	if (bond_mode_uses_xmit_hash(bond))
1868 		bond_update_slave_arr(bond, slave);
1869 
1870 	netdev_info(bond_dev, "Releasing %s interface %s\n",
1871 		    bond_is_active_slave(slave) ? "active" : "backup",
1872 		    slave_dev->name);
1873 
1874 	oldcurrent = rcu_access_pointer(bond->curr_active_slave);
1875 
1876 	RCU_INIT_POINTER(bond->current_arp_slave, NULL);
1877 
1878 	if (!all && (!bond->params.fail_over_mac ||
1879 		     BOND_MODE(bond) != BOND_MODE_ACTIVEBACKUP)) {
1880 		if (ether_addr_equal_64bits(bond_dev->dev_addr, slave->perm_hwaddr) &&
1881 		    bond_has_slaves(bond))
1882 			netdev_warn(bond_dev, "the permanent HWaddr of %s - %pM - is still in use by %s - set the HWaddr of %s to a different address to avoid conflicts\n",
1883 				    slave_dev->name, slave->perm_hwaddr,
1884 				    bond_dev->name, slave_dev->name);
1885 	}
1886 
1887 	if (rtnl_dereference(bond->primary_slave) == slave)
1888 		RCU_INIT_POINTER(bond->primary_slave, NULL);
1889 
1890 	if (oldcurrent == slave)
1891 		bond_change_active_slave(bond, NULL);
1892 
1893 	if (bond_is_lb(bond)) {
1894 		/* Must be called only after the slave has been
1895 		 * detached from the list and the curr_active_slave
1896 		 * has been cleared (if our_slave == old_current),
1897 		 * but before a new active slave is selected.
1898 		 */
1899 		bond_alb_deinit_slave(bond, slave);
1900 	}
1901 
1902 	if (all) {
1903 		RCU_INIT_POINTER(bond->curr_active_slave, NULL);
1904 	} else if (oldcurrent == slave) {
1905 		/* Note that we hold RTNL over this sequence, so there
1906 		 * is no concern that another slave add/remove event
1907 		 * will interfere.
1908 		 */
1909 		bond_select_active_slave(bond);
1910 	}
1911 
1912 	if (!bond_has_slaves(bond)) {
1913 		bond_set_carrier(bond);
1914 		eth_hw_addr_random(bond_dev);
1915 	}
1916 
1917 	unblock_netpoll_tx();
1918 	synchronize_rcu();
1919 	bond->slave_cnt--;
1920 
1921 	if (!bond_has_slaves(bond)) {
1922 		call_netdevice_notifiers(NETDEV_CHANGEADDR, bond->dev);
1923 		call_netdevice_notifiers(NETDEV_RELEASE, bond->dev);
1924 	}
1925 
1926 	bond_compute_features(bond);
1927 	if (!(bond_dev->features & NETIF_F_VLAN_CHALLENGED) &&
1928 	    (old_features & NETIF_F_VLAN_CHALLENGED))
1929 		netdev_info(bond_dev, "last VLAN challenged slave %s left bond %s - VLAN blocking is removed\n",
1930 			    slave_dev->name, bond_dev->name);
1931 
1932 	vlan_vids_del_by_dev(slave_dev, bond_dev);
1933 
1934 	/* If the mode uses primary, then this case was handled above by
1935 	 * bond_change_active_slave(..., NULL)
1936 	 */
1937 	if (!bond_uses_primary(bond)) {
1938 		/* unset promiscuity level from slave
1939 		 * NOTE: The NETDEV_CHANGEADDR call above may change the value
1940 		 * of the IFF_PROMISC flag in the bond_dev, but we need the
1941 		 * value of that flag before that change, as that was the value
1942 		 * when this slave was attached, so we cache at the start of the
1943 		 * function and use it here. Same goes for ALLMULTI below
1944 		 */
1945 		if (old_flags & IFF_PROMISC)
1946 			dev_set_promiscuity(slave_dev, -1);
1947 
1948 		/* unset allmulti level from slave */
1949 		if (old_flags & IFF_ALLMULTI)
1950 			dev_set_allmulti(slave_dev, -1);
1951 
1952 		bond_hw_addr_flush(bond_dev, slave_dev);
1953 	}
1954 
1955 	slave_disable_netpoll(slave);
1956 
1957 	/* close slave before restoring its mac address */
1958 	dev_close(slave_dev);
1959 
1960 	if (bond->params.fail_over_mac != BOND_FOM_ACTIVE ||
1961 	    BOND_MODE(bond) != BOND_MODE_ACTIVEBACKUP) {
1962 		/* restore original ("permanent") mac address */
1963 		bond_hw_addr_copy(ss.__data, slave->perm_hwaddr,
1964 				  slave->dev->addr_len);
1965 		ss.ss_family = slave_dev->type;
1966 		dev_set_mac_address(slave_dev, (struct sockaddr *)&ss);
1967 	}
1968 
1969 	if (unregister)
1970 		__dev_set_mtu(slave_dev, slave->original_mtu);
1971 	else
1972 		dev_set_mtu(slave_dev, slave->original_mtu);
1973 
1974 	slave_dev->priv_flags &= ~IFF_BONDING;
1975 
1976 	bond_free_slave(slave);
1977 
1978 	return 0;
1979 }
1980 
1981 /* A wrapper used because of ndo_del_link */
1982 int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
1983 {
1984 	return __bond_release_one(bond_dev, slave_dev, false, false);
1985 }
1986 
1987 /* First release a slave and then destroy the bond if no more slaves are left.
1988  * Must be under rtnl_lock when this function is called.
1989  */
1990 static int  bond_release_and_destroy(struct net_device *bond_dev,
1991 				     struct net_device *slave_dev)
1992 {
1993 	struct bonding *bond = netdev_priv(bond_dev);
1994 	int ret;
1995 
1996 	ret = __bond_release_one(bond_dev, slave_dev, false, true);
1997 	if (ret == 0 && !bond_has_slaves(bond)) {
1998 		bond_dev->priv_flags |= IFF_DISABLE_NETPOLL;
1999 		netdev_info(bond_dev, "Destroying bond %s\n",
2000 			    bond_dev->name);
2001 		bond_remove_proc_entry(bond);
2002 		unregister_netdevice(bond_dev);
2003 	}
2004 	return ret;
2005 }
2006 
2007 static void bond_info_query(struct net_device *bond_dev, struct ifbond *info)
2008 {
2009 	struct bonding *bond = netdev_priv(bond_dev);
2010 	bond_fill_ifbond(bond, info);
2011 }
2012 
2013 static int bond_slave_info_query(struct net_device *bond_dev, struct ifslave *info)
2014 {
2015 	struct bonding *bond = netdev_priv(bond_dev);
2016 	struct list_head *iter;
2017 	int i = 0, res = -ENODEV;
2018 	struct slave *slave;
2019 
2020 	bond_for_each_slave(bond, slave, iter) {
2021 		if (i++ == (int)info->slave_id) {
2022 			res = 0;
2023 			bond_fill_ifslave(slave, info);
2024 			break;
2025 		}
2026 	}
2027 
2028 	return res;
2029 }
2030 
2031 /*-------------------------------- Monitoring -------------------------------*/
2032 
2033 /* called with rcu_read_lock() */
2034 static int bond_miimon_inspect(struct bonding *bond)
2035 {
2036 	int link_state, commit = 0;
2037 	struct list_head *iter;
2038 	struct slave *slave;
2039 	bool ignore_updelay;
2040 
2041 	ignore_updelay = !rcu_dereference(bond->curr_active_slave);
2042 
2043 	bond_for_each_slave_rcu(bond, slave, iter) {
2044 		slave->new_link = BOND_LINK_NOCHANGE;
2045 
2046 		link_state = bond_check_dev_link(bond, slave->dev, 0);
2047 
2048 		switch (slave->link) {
2049 		case BOND_LINK_UP:
2050 			if (link_state)
2051 				continue;
2052 
2053 			bond_propose_link_state(slave, BOND_LINK_FAIL);
2054 			commit++;
2055 			slave->delay = bond->params.downdelay;
2056 			if (slave->delay) {
2057 				netdev_info(bond->dev, "link status down for %sinterface %s, disabling it in %d ms\n",
2058 					    (BOND_MODE(bond) ==
2059 					     BOND_MODE_ACTIVEBACKUP) ?
2060 					     (bond_is_active_slave(slave) ?
2061 					      "active " : "backup ") : "",
2062 					    slave->dev->name,
2063 					    bond->params.downdelay * bond->params.miimon);
2064 			}
2065 			/*FALLTHRU*/
2066 		case BOND_LINK_FAIL:
2067 			if (link_state) {
2068 				/* recovered before downdelay expired */
2069 				bond_propose_link_state(slave, BOND_LINK_UP);
2070 				slave->last_link_up = jiffies;
2071 				netdev_info(bond->dev, "link status up again after %d ms for interface %s\n",
2072 					    (bond->params.downdelay - slave->delay) *
2073 					    bond->params.miimon,
2074 					    slave->dev->name);
2075 				commit++;
2076 				continue;
2077 			}
2078 
2079 			if (slave->delay <= 0) {
2080 				slave->new_link = BOND_LINK_DOWN;
2081 				commit++;
2082 				continue;
2083 			}
2084 
2085 			slave->delay--;
2086 			break;
2087 
2088 		case BOND_LINK_DOWN:
2089 			if (!link_state)
2090 				continue;
2091 
2092 			bond_propose_link_state(slave, BOND_LINK_BACK);
2093 			commit++;
2094 			slave->delay = bond->params.updelay;
2095 
2096 			if (slave->delay) {
2097 				netdev_info(bond->dev, "link status up for interface %s, enabling it in %d ms\n",
2098 					    slave->dev->name,
2099 					    ignore_updelay ? 0 :
2100 					    bond->params.updelay *
2101 					    bond->params.miimon);
2102 			}
2103 			/*FALLTHRU*/
2104 		case BOND_LINK_BACK:
2105 			if (!link_state) {
2106 				bond_propose_link_state(slave, BOND_LINK_DOWN);
2107 				netdev_info(bond->dev, "link status down again after %d ms for interface %s\n",
2108 					    (bond->params.updelay - slave->delay) *
2109 					    bond->params.miimon,
2110 					    slave->dev->name);
2111 				commit++;
2112 				continue;
2113 			}
2114 
2115 			if (ignore_updelay)
2116 				slave->delay = 0;
2117 
2118 			if (slave->delay <= 0) {
2119 				slave->new_link = BOND_LINK_UP;
2120 				commit++;
2121 				ignore_updelay = false;
2122 				continue;
2123 			}
2124 
2125 			slave->delay--;
2126 			break;
2127 		}
2128 	}
2129 
2130 	return commit;
2131 }
2132 
2133 static void bond_miimon_commit(struct bonding *bond)
2134 {
2135 	struct list_head *iter;
2136 	struct slave *slave, *primary;
2137 
2138 	bond_for_each_slave(bond, slave, iter) {
2139 		switch (slave->new_link) {
2140 		case BOND_LINK_NOCHANGE:
2141 			continue;
2142 
2143 		case BOND_LINK_UP:
2144 			if (bond_update_speed_duplex(slave) &&
2145 			    bond_needs_speed_duplex(bond)) {
2146 				slave->link = BOND_LINK_DOWN;
2147 				if (net_ratelimit())
2148 					netdev_warn(bond->dev,
2149 						    "failed to get link speed/duplex for %s\n",
2150 						    slave->dev->name);
2151 				continue;
2152 			}
2153 			bond_set_slave_link_state(slave, BOND_LINK_UP,
2154 						  BOND_SLAVE_NOTIFY_NOW);
2155 			slave->last_link_up = jiffies;
2156 
2157 			primary = rtnl_dereference(bond->primary_slave);
2158 			if (BOND_MODE(bond) == BOND_MODE_8023AD) {
2159 				/* prevent it from being the active one */
2160 				bond_set_backup_slave(slave);
2161 			} else if (BOND_MODE(bond) != BOND_MODE_ACTIVEBACKUP) {
2162 				/* make it immediately active */
2163 				bond_set_active_slave(slave);
2164 			} else if (slave != primary) {
2165 				/* prevent it from being the active one */
2166 				bond_set_backup_slave(slave);
2167 			}
2168 
2169 			netdev_info(bond->dev, "link status definitely up for interface %s, %u Mbps %s duplex\n",
2170 				    slave->dev->name,
2171 				    slave->speed == SPEED_UNKNOWN ? 0 : slave->speed,
2172 				    slave->duplex ? "full" : "half");
2173 
2174 			/* notify ad that the link status has changed */
2175 			if (BOND_MODE(bond) == BOND_MODE_8023AD)
2176 				bond_3ad_handle_link_change(slave, BOND_LINK_UP);
2177 
2178 			if (bond_is_lb(bond))
2179 				bond_alb_handle_link_change(bond, slave,
2180 							    BOND_LINK_UP);
2181 
2182 			if (BOND_MODE(bond) == BOND_MODE_XOR)
2183 				bond_update_slave_arr(bond, NULL);
2184 
2185 			if (!bond->curr_active_slave || slave == primary)
2186 				goto do_failover;
2187 
2188 			continue;
2189 
2190 		case BOND_LINK_DOWN:
2191 			if (slave->link_failure_count < UINT_MAX)
2192 				slave->link_failure_count++;
2193 
2194 			bond_set_slave_link_state(slave, BOND_LINK_DOWN,
2195 						  BOND_SLAVE_NOTIFY_NOW);
2196 
2197 			if (BOND_MODE(bond) == BOND_MODE_ACTIVEBACKUP ||
2198 			    BOND_MODE(bond) == BOND_MODE_8023AD)
2199 				bond_set_slave_inactive_flags(slave,
2200 							      BOND_SLAVE_NOTIFY_NOW);
2201 
2202 			netdev_info(bond->dev, "link status definitely down for interface %s, disabling it\n",
2203 				    slave->dev->name);
2204 
2205 			if (BOND_MODE(bond) == BOND_MODE_8023AD)
2206 				bond_3ad_handle_link_change(slave,
2207 							    BOND_LINK_DOWN);
2208 
2209 			if (bond_is_lb(bond))
2210 				bond_alb_handle_link_change(bond, slave,
2211 							    BOND_LINK_DOWN);
2212 
2213 			if (BOND_MODE(bond) == BOND_MODE_XOR)
2214 				bond_update_slave_arr(bond, NULL);
2215 
2216 			if (slave == rcu_access_pointer(bond->curr_active_slave))
2217 				goto do_failover;
2218 
2219 			continue;
2220 
2221 		default:
2222 			netdev_err(bond->dev, "invalid new link %d on slave %s\n",
2223 				   slave->new_link, slave->dev->name);
2224 			slave->new_link = BOND_LINK_NOCHANGE;
2225 
2226 			continue;
2227 		}
2228 
2229 do_failover:
2230 		block_netpoll_tx();
2231 		bond_select_active_slave(bond);
2232 		unblock_netpoll_tx();
2233 	}
2234 
2235 	bond_set_carrier(bond);
2236 }
2237 
2238 /* bond_mii_monitor
2239  *
2240  * Really a wrapper that splits the mii monitor into two phases: an
2241  * inspection, then (if inspection indicates something needs to be done)
2242  * an acquisition of appropriate locks followed by a commit phase to
2243  * implement whatever link state changes are indicated.
2244  */
2245 static void bond_mii_monitor(struct work_struct *work)
2246 {
2247 	struct bonding *bond = container_of(work, struct bonding,
2248 					    mii_work.work);
2249 	bool should_notify_peers = false;
2250 	unsigned long delay;
2251 	struct slave *slave;
2252 	struct list_head *iter;
2253 
2254 	delay = msecs_to_jiffies(bond->params.miimon);
2255 
2256 	if (!bond_has_slaves(bond))
2257 		goto re_arm;
2258 
2259 	rcu_read_lock();
2260 
2261 	should_notify_peers = bond_should_notify_peers(bond);
2262 
2263 	if (bond_miimon_inspect(bond)) {
2264 		rcu_read_unlock();
2265 
2266 		/* Race avoidance with bond_close cancel of workqueue */
2267 		if (!rtnl_trylock()) {
2268 			delay = 1;
2269 			should_notify_peers = false;
2270 			goto re_arm;
2271 		}
2272 
2273 		bond_for_each_slave(bond, slave, iter) {
2274 			bond_commit_link_state(slave, BOND_SLAVE_NOTIFY_LATER);
2275 		}
2276 		bond_miimon_commit(bond);
2277 
2278 		rtnl_unlock();	/* might sleep, hold no other locks */
2279 	} else
2280 		rcu_read_unlock();
2281 
2282 re_arm:
2283 	if (bond->params.miimon)
2284 		queue_delayed_work(bond->wq, &bond->mii_work, delay);
2285 
2286 	if (should_notify_peers) {
2287 		if (!rtnl_trylock())
2288 			return;
2289 		call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, bond->dev);
2290 		rtnl_unlock();
2291 	}
2292 }
2293 
2294 static int bond_upper_dev_walk(struct net_device *upper, void *data)
2295 {
2296 	__be32 ip = *((__be32 *)data);
2297 
2298 	return ip == bond_confirm_addr(upper, 0, ip);
2299 }
2300 
2301 static bool bond_has_this_ip(struct bonding *bond, __be32 ip)
2302 {
2303 	bool ret = false;
2304 
2305 	if (ip == bond_confirm_addr(bond->dev, 0, ip))
2306 		return true;
2307 
2308 	rcu_read_lock();
2309 	if (netdev_walk_all_upper_dev_rcu(bond->dev, bond_upper_dev_walk, &ip))
2310 		ret = true;
2311 	rcu_read_unlock();
2312 
2313 	return ret;
2314 }
2315 
2316 /* We go to the (large) trouble of VLAN tagging ARP frames because
2317  * switches in VLAN mode (especially if ports are configured as
2318  * "native" to a VLAN) might not pass non-tagged frames.
2319  */
2320 static void bond_arp_send(struct net_device *slave_dev, int arp_op,
2321 			  __be32 dest_ip, __be32 src_ip,
2322 			  struct bond_vlan_tag *tags)
2323 {
2324 	struct sk_buff *skb;
2325 	struct bond_vlan_tag *outer_tag = tags;
2326 
2327 	netdev_dbg(slave_dev, "arp %d on slave %s: dst %pI4 src %pI4\n",
2328 		   arp_op, slave_dev->name, &dest_ip, &src_ip);
2329 
2330 	skb = arp_create(arp_op, ETH_P_ARP, dest_ip, slave_dev, src_ip,
2331 			 NULL, slave_dev->dev_addr, NULL);
2332 
2333 	if (!skb) {
2334 		net_err_ratelimited("ARP packet allocation failed\n");
2335 		return;
2336 	}
2337 
2338 	if (!tags || tags->vlan_proto == VLAN_N_VID)
2339 		goto xmit;
2340 
2341 	tags++;
2342 
2343 	/* Go through all the tags backwards and add them to the packet */
2344 	while (tags->vlan_proto != VLAN_N_VID) {
2345 		if (!tags->vlan_id) {
2346 			tags++;
2347 			continue;
2348 		}
2349 
2350 		netdev_dbg(slave_dev, "inner tag: proto %X vid %X\n",
2351 			   ntohs(outer_tag->vlan_proto), tags->vlan_id);
2352 		skb = vlan_insert_tag_set_proto(skb, tags->vlan_proto,
2353 						tags->vlan_id);
2354 		if (!skb) {
2355 			net_err_ratelimited("failed to insert inner VLAN tag\n");
2356 			return;
2357 		}
2358 
2359 		tags++;
2360 	}
2361 	/* Set the outer tag */
2362 	if (outer_tag->vlan_id) {
2363 		netdev_dbg(slave_dev, "outer tag: proto %X vid %X\n",
2364 			   ntohs(outer_tag->vlan_proto), outer_tag->vlan_id);
2365 		__vlan_hwaccel_put_tag(skb, outer_tag->vlan_proto,
2366 				       outer_tag->vlan_id);
2367 	}
2368 
2369 xmit:
2370 	arp_xmit(skb);
2371 }
2372 
2373 /* Validate the device path between the @start_dev and the @end_dev.
2374  * The path is valid if the @end_dev is reachable through device
2375  * stacking.
2376  * When the path is validated, collect any vlan information in the
2377  * path.
2378  */
2379 struct bond_vlan_tag *bond_verify_device_path(struct net_device *start_dev,
2380 					      struct net_device *end_dev,
2381 					      int level)
2382 {
2383 	struct bond_vlan_tag *tags;
2384 	struct net_device *upper;
2385 	struct list_head  *iter;
2386 
2387 	if (start_dev == end_dev) {
2388 		tags = kzalloc(sizeof(*tags) * (level + 1), GFP_ATOMIC);
2389 		if (!tags)
2390 			return ERR_PTR(-ENOMEM);
2391 		tags[level].vlan_proto = VLAN_N_VID;
2392 		return tags;
2393 	}
2394 
2395 	netdev_for_each_upper_dev_rcu(start_dev, upper, iter) {
2396 		tags = bond_verify_device_path(upper, end_dev, level + 1);
2397 		if (IS_ERR_OR_NULL(tags)) {
2398 			if (IS_ERR(tags))
2399 				return tags;
2400 			continue;
2401 		}
2402 		if (is_vlan_dev(upper)) {
2403 			tags[level].vlan_proto = vlan_dev_vlan_proto(upper);
2404 			tags[level].vlan_id = vlan_dev_vlan_id(upper);
2405 		}
2406 
2407 		return tags;
2408 	}
2409 
2410 	return NULL;
2411 }
2412 
2413 static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
2414 {
2415 	struct rtable *rt;
2416 	struct bond_vlan_tag *tags;
2417 	__be32 *targets = bond->params.arp_targets, addr;
2418 	int i;
2419 
2420 	for (i = 0; i < BOND_MAX_ARP_TARGETS && targets[i]; i++) {
2421 		netdev_dbg(bond->dev, "basa: target %pI4\n", &targets[i]);
2422 		tags = NULL;
2423 
2424 		/* Find out through which dev should the packet go */
2425 		rt = ip_route_output(dev_net(bond->dev), targets[i], 0,
2426 				     RTO_ONLINK, 0);
2427 		if (IS_ERR(rt)) {
2428 			/* there's no route to target - try to send arp
2429 			 * probe to generate any traffic (arp_validate=0)
2430 			 */
2431 			if (bond->params.arp_validate)
2432 				net_warn_ratelimited("%s: no route to arp_ip_target %pI4 and arp_validate is set\n",
2433 						     bond->dev->name,
2434 						     &targets[i]);
2435 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2436 				      0, tags);
2437 			continue;
2438 		}
2439 
2440 		/* bond device itself */
2441 		if (rt->dst.dev == bond->dev)
2442 			goto found;
2443 
2444 		rcu_read_lock();
2445 		tags = bond_verify_device_path(bond->dev, rt->dst.dev, 0);
2446 		rcu_read_unlock();
2447 
2448 		if (!IS_ERR_OR_NULL(tags))
2449 			goto found;
2450 
2451 		/* Not our device - skip */
2452 		netdev_dbg(bond->dev, "no path to arp_ip_target %pI4 via rt.dev %s\n",
2453 			   &targets[i], rt->dst.dev ? rt->dst.dev->name : "NULL");
2454 
2455 		ip_rt_put(rt);
2456 		continue;
2457 
2458 found:
2459 		addr = bond_confirm_addr(rt->dst.dev, targets[i], 0);
2460 		ip_rt_put(rt);
2461 		bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2462 			      addr, tags);
2463 		kfree(tags);
2464 	}
2465 }
2466 
2467 static void bond_validate_arp(struct bonding *bond, struct slave *slave, __be32 sip, __be32 tip)
2468 {
2469 	int i;
2470 
2471 	if (!sip || !bond_has_this_ip(bond, tip)) {
2472 		netdev_dbg(bond->dev, "bva: sip %pI4 tip %pI4 not found\n",
2473 			   &sip, &tip);
2474 		return;
2475 	}
2476 
2477 	i = bond_get_targets_ip(bond->params.arp_targets, sip);
2478 	if (i == -1) {
2479 		netdev_dbg(bond->dev, "bva: sip %pI4 not found in targets\n",
2480 			   &sip);
2481 		return;
2482 	}
2483 	slave->last_rx = jiffies;
2484 	slave->target_last_arp_rx[i] = jiffies;
2485 }
2486 
2487 int bond_arp_rcv(const struct sk_buff *skb, struct bonding *bond,
2488 		 struct slave *slave)
2489 {
2490 	struct arphdr *arp = (struct arphdr *)skb->data;
2491 	struct slave *curr_active_slave, *curr_arp_slave;
2492 	unsigned char *arp_ptr;
2493 	__be32 sip, tip;
2494 	int alen, is_arp = skb->protocol == __cpu_to_be16(ETH_P_ARP);
2495 
2496 	if (!slave_do_arp_validate(bond, slave)) {
2497 		if ((slave_do_arp_validate_only(bond) && is_arp) ||
2498 		    !slave_do_arp_validate_only(bond))
2499 			slave->last_rx = jiffies;
2500 		return RX_HANDLER_ANOTHER;
2501 	} else if (!is_arp) {
2502 		return RX_HANDLER_ANOTHER;
2503 	}
2504 
2505 	alen = arp_hdr_len(bond->dev);
2506 
2507 	netdev_dbg(bond->dev, "bond_arp_rcv: skb->dev %s\n",
2508 		   skb->dev->name);
2509 
2510 	if (alen > skb_headlen(skb)) {
2511 		arp = kmalloc(alen, GFP_ATOMIC);
2512 		if (!arp)
2513 			goto out_unlock;
2514 		if (skb_copy_bits(skb, 0, arp, alen) < 0)
2515 			goto out_unlock;
2516 	}
2517 
2518 	if (arp->ar_hln != bond->dev->addr_len ||
2519 	    skb->pkt_type == PACKET_OTHERHOST ||
2520 	    skb->pkt_type == PACKET_LOOPBACK ||
2521 	    arp->ar_hrd != htons(ARPHRD_ETHER) ||
2522 	    arp->ar_pro != htons(ETH_P_IP) ||
2523 	    arp->ar_pln != 4)
2524 		goto out_unlock;
2525 
2526 	arp_ptr = (unsigned char *)(arp + 1);
2527 	arp_ptr += bond->dev->addr_len;
2528 	memcpy(&sip, arp_ptr, 4);
2529 	arp_ptr += 4 + bond->dev->addr_len;
2530 	memcpy(&tip, arp_ptr, 4);
2531 
2532 	netdev_dbg(bond->dev, "bond_arp_rcv: %s/%d av %d sv %d sip %pI4 tip %pI4\n",
2533 		   slave->dev->name, bond_slave_state(slave),
2534 		     bond->params.arp_validate, slave_do_arp_validate(bond, slave),
2535 		     &sip, &tip);
2536 
2537 	curr_active_slave = rcu_dereference(bond->curr_active_slave);
2538 	curr_arp_slave = rcu_dereference(bond->current_arp_slave);
2539 
2540 	/* We 'trust' the received ARP enough to validate it if:
2541 	 *
2542 	 * (a) the slave receiving the ARP is active (which includes the
2543 	 * current ARP slave, if any), or
2544 	 *
2545 	 * (b) the receiving slave isn't active, but there is a currently
2546 	 * active slave and it received valid arp reply(s) after it became
2547 	 * the currently active slave, or
2548 	 *
2549 	 * (c) there is an ARP slave that sent an ARP during the prior ARP
2550 	 * interval, and we receive an ARP reply on any slave.  We accept
2551 	 * these because switch FDB update delays may deliver the ARP
2552 	 * reply to a slave other than the sender of the ARP request.
2553 	 *
2554 	 * Note: for (b), backup slaves are receiving the broadcast ARP
2555 	 * request, not a reply.  This request passes from the sending
2556 	 * slave through the L2 switch(es) to the receiving slave.  Since
2557 	 * this is checking the request, sip/tip are swapped for
2558 	 * validation.
2559 	 *
2560 	 * This is done to avoid endless looping when we can't reach the
2561 	 * arp_ip_target and fool ourselves with our own arp requests.
2562 	 */
2563 	if (bond_is_active_slave(slave))
2564 		bond_validate_arp(bond, slave, sip, tip);
2565 	else if (curr_active_slave &&
2566 		 time_after(slave_last_rx(bond, curr_active_slave),
2567 			    curr_active_slave->last_link_up))
2568 		bond_validate_arp(bond, slave, tip, sip);
2569 	else if (curr_arp_slave && (arp->ar_op == htons(ARPOP_REPLY)) &&
2570 		 bond_time_in_interval(bond,
2571 				       dev_trans_start(curr_arp_slave->dev), 1))
2572 		bond_validate_arp(bond, slave, sip, tip);
2573 
2574 out_unlock:
2575 	if (arp != (struct arphdr *)skb->data)
2576 		kfree(arp);
2577 	return RX_HANDLER_ANOTHER;
2578 }
2579 
2580 /* function to verify if we're in the arp_interval timeslice, returns true if
2581  * (last_act - arp_interval) <= jiffies <= (last_act + mod * arp_interval +
2582  * arp_interval/2) . the arp_interval/2 is needed for really fast networks.
2583  */
2584 static bool bond_time_in_interval(struct bonding *bond, unsigned long last_act,
2585 				  int mod)
2586 {
2587 	int delta_in_ticks = msecs_to_jiffies(bond->params.arp_interval);
2588 
2589 	return time_in_range(jiffies,
2590 			     last_act - delta_in_ticks,
2591 			     last_act + mod * delta_in_ticks + delta_in_ticks/2);
2592 }
2593 
2594 /* This function is called regularly to monitor each slave's link
2595  * ensuring that traffic is being sent and received when arp monitoring
2596  * is used in load-balancing mode. if the adapter has been dormant, then an
2597  * arp is transmitted to generate traffic. see activebackup_arp_monitor for
2598  * arp monitoring in active backup mode.
2599  */
2600 static void bond_loadbalance_arp_mon(struct bonding *bond)
2601 {
2602 	struct slave *slave, *oldcurrent;
2603 	struct list_head *iter;
2604 	int do_failover = 0, slave_state_changed = 0;
2605 
2606 	if (!bond_has_slaves(bond))
2607 		goto re_arm;
2608 
2609 	rcu_read_lock();
2610 
2611 	oldcurrent = rcu_dereference(bond->curr_active_slave);
2612 	/* see if any of the previous devices are up now (i.e. they have
2613 	 * xmt and rcv traffic). the curr_active_slave does not come into
2614 	 * the picture unless it is null. also, slave->last_link_up is not
2615 	 * needed here because we send an arp on each slave and give a slave
2616 	 * as long as it needs to get the tx/rx within the delta.
2617 	 * TODO: what about up/down delay in arp mode? it wasn't here before
2618 	 *       so it can wait
2619 	 */
2620 	bond_for_each_slave_rcu(bond, slave, iter) {
2621 		unsigned long trans_start = dev_trans_start(slave->dev);
2622 
2623 		slave->new_link = BOND_LINK_NOCHANGE;
2624 
2625 		if (slave->link != BOND_LINK_UP) {
2626 			if (bond_time_in_interval(bond, trans_start, 1) &&
2627 			    bond_time_in_interval(bond, slave->last_rx, 1)) {
2628 
2629 				slave->new_link = BOND_LINK_UP;
2630 				slave_state_changed = 1;
2631 
2632 				/* primary_slave has no meaning in round-robin
2633 				 * mode. the window of a slave being up and
2634 				 * curr_active_slave being null after enslaving
2635 				 * is closed.
2636 				 */
2637 				if (!oldcurrent) {
2638 					netdev_info(bond->dev, "link status definitely up for interface %s\n",
2639 						    slave->dev->name);
2640 					do_failover = 1;
2641 				} else {
2642 					netdev_info(bond->dev, "interface %s is now up\n",
2643 						    slave->dev->name);
2644 				}
2645 			}
2646 		} else {
2647 			/* slave->link == BOND_LINK_UP */
2648 
2649 			/* not all switches will respond to an arp request
2650 			 * when the source ip is 0, so don't take the link down
2651 			 * if we don't know our ip yet
2652 			 */
2653 			if (!bond_time_in_interval(bond, trans_start, 2) ||
2654 			    !bond_time_in_interval(bond, slave->last_rx, 2)) {
2655 
2656 				slave->new_link = BOND_LINK_DOWN;
2657 				slave_state_changed = 1;
2658 
2659 				if (slave->link_failure_count < UINT_MAX)
2660 					slave->link_failure_count++;
2661 
2662 				netdev_info(bond->dev, "interface %s is now down\n",
2663 					    slave->dev->name);
2664 
2665 				if (slave == oldcurrent)
2666 					do_failover = 1;
2667 			}
2668 		}
2669 
2670 		/* note: if switch is in round-robin mode, all links
2671 		 * must tx arp to ensure all links rx an arp - otherwise
2672 		 * links may oscillate or not come up at all; if switch is
2673 		 * in something like xor mode, there is nothing we can
2674 		 * do - all replies will be rx'ed on same link causing slaves
2675 		 * to be unstable during low/no traffic periods
2676 		 */
2677 		if (bond_slave_is_up(slave))
2678 			bond_arp_send_all(bond, slave);
2679 	}
2680 
2681 	rcu_read_unlock();
2682 
2683 	if (do_failover || slave_state_changed) {
2684 		if (!rtnl_trylock())
2685 			goto re_arm;
2686 
2687 		bond_for_each_slave(bond, slave, iter) {
2688 			if (slave->new_link != BOND_LINK_NOCHANGE)
2689 				slave->link = slave->new_link;
2690 		}
2691 
2692 		if (slave_state_changed) {
2693 			bond_slave_state_change(bond);
2694 			if (BOND_MODE(bond) == BOND_MODE_XOR)
2695 				bond_update_slave_arr(bond, NULL);
2696 		}
2697 		if (do_failover) {
2698 			block_netpoll_tx();
2699 			bond_select_active_slave(bond);
2700 			unblock_netpoll_tx();
2701 		}
2702 		rtnl_unlock();
2703 	}
2704 
2705 re_arm:
2706 	if (bond->params.arp_interval)
2707 		queue_delayed_work(bond->wq, &bond->arp_work,
2708 				   msecs_to_jiffies(bond->params.arp_interval));
2709 }
2710 
2711 /* Called to inspect slaves for active-backup mode ARP monitor link state
2712  * changes.  Sets new_link in slaves to specify what action should take
2713  * place for the slave.  Returns 0 if no changes are found, >0 if changes
2714  * to link states must be committed.
2715  *
2716  * Called with rcu_read_lock held.
2717  */
2718 static int bond_ab_arp_inspect(struct bonding *bond)
2719 {
2720 	unsigned long trans_start, last_rx;
2721 	struct list_head *iter;
2722 	struct slave *slave;
2723 	int commit = 0;
2724 
2725 	bond_for_each_slave_rcu(bond, slave, iter) {
2726 		slave->new_link = BOND_LINK_NOCHANGE;
2727 		last_rx = slave_last_rx(bond, slave);
2728 
2729 		if (slave->link != BOND_LINK_UP) {
2730 			if (bond_time_in_interval(bond, last_rx, 1)) {
2731 				slave->new_link = BOND_LINK_UP;
2732 				commit++;
2733 			}
2734 			continue;
2735 		}
2736 
2737 		/* Give slaves 2*delta after being enslaved or made
2738 		 * active.  This avoids bouncing, as the last receive
2739 		 * times need a full ARP monitor cycle to be updated.
2740 		 */
2741 		if (bond_time_in_interval(bond, slave->last_link_up, 2))
2742 			continue;
2743 
2744 		/* Backup slave is down if:
2745 		 * - No current_arp_slave AND
2746 		 * - more than 3*delta since last receive AND
2747 		 * - the bond has an IP address
2748 		 *
2749 		 * Note: a non-null current_arp_slave indicates
2750 		 * the curr_active_slave went down and we are
2751 		 * searching for a new one; under this condition
2752 		 * we only take the curr_active_slave down - this
2753 		 * gives each slave a chance to tx/rx traffic
2754 		 * before being taken out
2755 		 */
2756 		if (!bond_is_active_slave(slave) &&
2757 		    !rcu_access_pointer(bond->current_arp_slave) &&
2758 		    !bond_time_in_interval(bond, last_rx, 3)) {
2759 			slave->new_link = BOND_LINK_DOWN;
2760 			commit++;
2761 		}
2762 
2763 		/* Active slave is down if:
2764 		 * - more than 2*delta since transmitting OR
2765 		 * - (more than 2*delta since receive AND
2766 		 *    the bond has an IP address)
2767 		 */
2768 		trans_start = dev_trans_start(slave->dev);
2769 		if (bond_is_active_slave(slave) &&
2770 		    (!bond_time_in_interval(bond, trans_start, 2) ||
2771 		     !bond_time_in_interval(bond, last_rx, 2))) {
2772 			slave->new_link = BOND_LINK_DOWN;
2773 			commit++;
2774 		}
2775 	}
2776 
2777 	return commit;
2778 }
2779 
2780 /* Called to commit link state changes noted by inspection step of
2781  * active-backup mode ARP monitor.
2782  *
2783  * Called with RTNL hold.
2784  */
2785 static void bond_ab_arp_commit(struct bonding *bond)
2786 {
2787 	unsigned long trans_start;
2788 	struct list_head *iter;
2789 	struct slave *slave;
2790 
2791 	bond_for_each_slave(bond, slave, iter) {
2792 		switch (slave->new_link) {
2793 		case BOND_LINK_NOCHANGE:
2794 			continue;
2795 
2796 		case BOND_LINK_UP:
2797 			trans_start = dev_trans_start(slave->dev);
2798 			if (rtnl_dereference(bond->curr_active_slave) != slave ||
2799 			    (!rtnl_dereference(bond->curr_active_slave) &&
2800 			     bond_time_in_interval(bond, trans_start, 1))) {
2801 				struct slave *current_arp_slave;
2802 
2803 				current_arp_slave = rtnl_dereference(bond->current_arp_slave);
2804 				bond_set_slave_link_state(slave, BOND_LINK_UP,
2805 							  BOND_SLAVE_NOTIFY_NOW);
2806 				if (current_arp_slave) {
2807 					bond_set_slave_inactive_flags(
2808 						current_arp_slave,
2809 						BOND_SLAVE_NOTIFY_NOW);
2810 					RCU_INIT_POINTER(bond->current_arp_slave, NULL);
2811 				}
2812 
2813 				netdev_info(bond->dev, "link status definitely up for interface %s\n",
2814 					    slave->dev->name);
2815 
2816 				if (!rtnl_dereference(bond->curr_active_slave) ||
2817 				    slave == rtnl_dereference(bond->primary_slave))
2818 					goto do_failover;
2819 
2820 			}
2821 
2822 			continue;
2823 
2824 		case BOND_LINK_DOWN:
2825 			if (slave->link_failure_count < UINT_MAX)
2826 				slave->link_failure_count++;
2827 
2828 			bond_set_slave_link_state(slave, BOND_LINK_DOWN,
2829 						  BOND_SLAVE_NOTIFY_NOW);
2830 			bond_set_slave_inactive_flags(slave,
2831 						      BOND_SLAVE_NOTIFY_NOW);
2832 
2833 			netdev_info(bond->dev, "link status definitely down for interface %s, disabling it\n",
2834 				    slave->dev->name);
2835 
2836 			if (slave == rtnl_dereference(bond->curr_active_slave)) {
2837 				RCU_INIT_POINTER(bond->current_arp_slave, NULL);
2838 				goto do_failover;
2839 			}
2840 
2841 			continue;
2842 
2843 		default:
2844 			netdev_err(bond->dev, "impossible: new_link %d on slave %s\n",
2845 				   slave->new_link, slave->dev->name);
2846 			continue;
2847 		}
2848 
2849 do_failover:
2850 		block_netpoll_tx();
2851 		bond_select_active_slave(bond);
2852 		unblock_netpoll_tx();
2853 	}
2854 
2855 	bond_set_carrier(bond);
2856 }
2857 
2858 /* Send ARP probes for active-backup mode ARP monitor.
2859  *
2860  * Called with rcu_read_lock held.
2861  */
2862 static bool bond_ab_arp_probe(struct bonding *bond)
2863 {
2864 	struct slave *slave, *before = NULL, *new_slave = NULL,
2865 		     *curr_arp_slave = rcu_dereference(bond->current_arp_slave),
2866 		     *curr_active_slave = rcu_dereference(bond->curr_active_slave);
2867 	struct list_head *iter;
2868 	bool found = false;
2869 	bool should_notify_rtnl = BOND_SLAVE_NOTIFY_LATER;
2870 
2871 	if (curr_arp_slave && curr_active_slave)
2872 		netdev_info(bond->dev, "PROBE: c_arp %s && cas %s BAD\n",
2873 			    curr_arp_slave->dev->name,
2874 			    curr_active_slave->dev->name);
2875 
2876 	if (curr_active_slave) {
2877 		bond_arp_send_all(bond, curr_active_slave);
2878 		return should_notify_rtnl;
2879 	}
2880 
2881 	/* if we don't have a curr_active_slave, search for the next available
2882 	 * backup slave from the current_arp_slave and make it the candidate
2883 	 * for becoming the curr_active_slave
2884 	 */
2885 
2886 	if (!curr_arp_slave) {
2887 		curr_arp_slave = bond_first_slave_rcu(bond);
2888 		if (!curr_arp_slave)
2889 			return should_notify_rtnl;
2890 	}
2891 
2892 	bond_set_slave_inactive_flags(curr_arp_slave, BOND_SLAVE_NOTIFY_LATER);
2893 
2894 	bond_for_each_slave_rcu(bond, slave, iter) {
2895 		if (!found && !before && bond_slave_is_up(slave))
2896 			before = slave;
2897 
2898 		if (found && !new_slave && bond_slave_is_up(slave))
2899 			new_slave = slave;
2900 		/* if the link state is up at this point, we
2901 		 * mark it down - this can happen if we have
2902 		 * simultaneous link failures and
2903 		 * reselect_active_interface doesn't make this
2904 		 * one the current slave so it is still marked
2905 		 * up when it is actually down
2906 		 */
2907 		if (!bond_slave_is_up(slave) && slave->link == BOND_LINK_UP) {
2908 			bond_set_slave_link_state(slave, BOND_LINK_DOWN,
2909 						  BOND_SLAVE_NOTIFY_LATER);
2910 			if (slave->link_failure_count < UINT_MAX)
2911 				slave->link_failure_count++;
2912 
2913 			bond_set_slave_inactive_flags(slave,
2914 						      BOND_SLAVE_NOTIFY_LATER);
2915 
2916 			netdev_info(bond->dev, "backup interface %s is now down\n",
2917 				    slave->dev->name);
2918 		}
2919 		if (slave == curr_arp_slave)
2920 			found = true;
2921 	}
2922 
2923 	if (!new_slave && before)
2924 		new_slave = before;
2925 
2926 	if (!new_slave)
2927 		goto check_state;
2928 
2929 	bond_set_slave_link_state(new_slave, BOND_LINK_BACK,
2930 				  BOND_SLAVE_NOTIFY_LATER);
2931 	bond_set_slave_active_flags(new_slave, BOND_SLAVE_NOTIFY_LATER);
2932 	bond_arp_send_all(bond, new_slave);
2933 	new_slave->last_link_up = jiffies;
2934 	rcu_assign_pointer(bond->current_arp_slave, new_slave);
2935 
2936 check_state:
2937 	bond_for_each_slave_rcu(bond, slave, iter) {
2938 		if (slave->should_notify || slave->should_notify_link) {
2939 			should_notify_rtnl = BOND_SLAVE_NOTIFY_NOW;
2940 			break;
2941 		}
2942 	}
2943 	return should_notify_rtnl;
2944 }
2945 
2946 static void bond_activebackup_arp_mon(struct bonding *bond)
2947 {
2948 	bool should_notify_peers = false;
2949 	bool should_notify_rtnl = false;
2950 	int delta_in_ticks;
2951 
2952 	delta_in_ticks = msecs_to_jiffies(bond->params.arp_interval);
2953 
2954 	if (!bond_has_slaves(bond))
2955 		goto re_arm;
2956 
2957 	rcu_read_lock();
2958 
2959 	should_notify_peers = bond_should_notify_peers(bond);
2960 
2961 	if (bond_ab_arp_inspect(bond)) {
2962 		rcu_read_unlock();
2963 
2964 		/* Race avoidance with bond_close flush of workqueue */
2965 		if (!rtnl_trylock()) {
2966 			delta_in_ticks = 1;
2967 			should_notify_peers = false;
2968 			goto re_arm;
2969 		}
2970 
2971 		bond_ab_arp_commit(bond);
2972 
2973 		rtnl_unlock();
2974 		rcu_read_lock();
2975 	}
2976 
2977 	should_notify_rtnl = bond_ab_arp_probe(bond);
2978 	rcu_read_unlock();
2979 
2980 re_arm:
2981 	if (bond->params.arp_interval)
2982 		queue_delayed_work(bond->wq, &bond->arp_work, delta_in_ticks);
2983 
2984 	if (should_notify_peers || should_notify_rtnl) {
2985 		if (!rtnl_trylock())
2986 			return;
2987 
2988 		if (should_notify_peers)
2989 			call_netdevice_notifiers(NETDEV_NOTIFY_PEERS,
2990 						 bond->dev);
2991 		if (should_notify_rtnl) {
2992 			bond_slave_state_notify(bond);
2993 			bond_slave_link_notify(bond);
2994 		}
2995 
2996 		rtnl_unlock();
2997 	}
2998 }
2999 
3000 static void bond_arp_monitor(struct work_struct *work)
3001 {
3002 	struct bonding *bond = container_of(work, struct bonding,
3003 					    arp_work.work);
3004 
3005 	if (BOND_MODE(bond) == BOND_MODE_ACTIVEBACKUP)
3006 		bond_activebackup_arp_mon(bond);
3007 	else
3008 		bond_loadbalance_arp_mon(bond);
3009 }
3010 
3011 /*-------------------------- netdev event handling --------------------------*/
3012 
3013 /* Change device name */
3014 static int bond_event_changename(struct bonding *bond)
3015 {
3016 	bond_remove_proc_entry(bond);
3017 	bond_create_proc_entry(bond);
3018 
3019 	bond_debug_reregister(bond);
3020 
3021 	return NOTIFY_DONE;
3022 }
3023 
3024 static int bond_master_netdev_event(unsigned long event,
3025 				    struct net_device *bond_dev)
3026 {
3027 	struct bonding *event_bond = netdev_priv(bond_dev);
3028 
3029 	switch (event) {
3030 	case NETDEV_CHANGENAME:
3031 		return bond_event_changename(event_bond);
3032 	case NETDEV_UNREGISTER:
3033 		bond_remove_proc_entry(event_bond);
3034 		break;
3035 	case NETDEV_REGISTER:
3036 		bond_create_proc_entry(event_bond);
3037 		break;
3038 	case NETDEV_NOTIFY_PEERS:
3039 		if (event_bond->send_peer_notif)
3040 			event_bond->send_peer_notif--;
3041 		break;
3042 	default:
3043 		break;
3044 	}
3045 
3046 	return NOTIFY_DONE;
3047 }
3048 
3049 static int bond_slave_netdev_event(unsigned long event,
3050 				   struct net_device *slave_dev)
3051 {
3052 	struct slave *slave = bond_slave_get_rtnl(slave_dev), *primary;
3053 	struct bonding *bond;
3054 	struct net_device *bond_dev;
3055 
3056 	/* A netdev event can be generated while enslaving a device
3057 	 * before netdev_rx_handler_register is called in which case
3058 	 * slave will be NULL
3059 	 */
3060 	if (!slave)
3061 		return NOTIFY_DONE;
3062 	bond_dev = slave->bond->dev;
3063 	bond = slave->bond;
3064 	primary = rtnl_dereference(bond->primary_slave);
3065 
3066 	switch (event) {
3067 	case NETDEV_UNREGISTER:
3068 		if (bond_dev->type != ARPHRD_ETHER)
3069 			bond_release_and_destroy(bond_dev, slave_dev);
3070 		else
3071 			__bond_release_one(bond_dev, slave_dev, false, true);
3072 		break;
3073 	case NETDEV_UP:
3074 	case NETDEV_CHANGE:
3075 		bond_update_speed_duplex(slave);
3076 		if (BOND_MODE(bond) == BOND_MODE_8023AD)
3077 			bond_3ad_adapter_speed_duplex_changed(slave);
3078 		/* Fallthrough */
3079 	case NETDEV_DOWN:
3080 		/* Refresh slave-array if applicable!
3081 		 * If the setup does not use miimon or arpmon (mode-specific!),
3082 		 * then these events will not cause the slave-array to be
3083 		 * refreshed. This will cause xmit to use a slave that is not
3084 		 * usable. Avoid such situation by refeshing the array at these
3085 		 * events. If these (miimon/arpmon) parameters are configured
3086 		 * then array gets refreshed twice and that should be fine!
3087 		 */
3088 		if (bond_mode_uses_xmit_hash(bond))
3089 			bond_update_slave_arr(bond, NULL);
3090 		break;
3091 	case NETDEV_CHANGEMTU:
3092 		/* TODO: Should slaves be allowed to
3093 		 * independently alter their MTU?  For
3094 		 * an active-backup bond, slaves need
3095 		 * not be the same type of device, so
3096 		 * MTUs may vary.  For other modes,
3097 		 * slaves arguably should have the
3098 		 * same MTUs. To do this, we'd need to
3099 		 * take over the slave's change_mtu
3100 		 * function for the duration of their
3101 		 * servitude.
3102 		 */
3103 		break;
3104 	case NETDEV_CHANGENAME:
3105 		/* we don't care if we don't have primary set */
3106 		if (!bond_uses_primary(bond) ||
3107 		    !bond->params.primary[0])
3108 			break;
3109 
3110 		if (slave == primary) {
3111 			/* slave's name changed - he's no longer primary */
3112 			RCU_INIT_POINTER(bond->primary_slave, NULL);
3113 		} else if (!strcmp(slave_dev->name, bond->params.primary)) {
3114 			/* we have a new primary slave */
3115 			rcu_assign_pointer(bond->primary_slave, slave);
3116 		} else { /* we didn't change primary - exit */
3117 			break;
3118 		}
3119 
3120 		netdev_info(bond->dev, "Primary slave changed to %s, reselecting active slave\n",
3121 			    primary ? slave_dev->name : "none");
3122 
3123 		block_netpoll_tx();
3124 		bond_select_active_slave(bond);
3125 		unblock_netpoll_tx();
3126 		break;
3127 	case NETDEV_FEAT_CHANGE:
3128 		bond_compute_features(bond);
3129 		break;
3130 	case NETDEV_RESEND_IGMP:
3131 		/* Propagate to master device */
3132 		call_netdevice_notifiers(event, slave->bond->dev);
3133 		break;
3134 	default:
3135 		break;
3136 	}
3137 
3138 	return NOTIFY_DONE;
3139 }
3140 
3141 /* bond_netdev_event: handle netdev notifier chain events.
3142  *
3143  * This function receives events for the netdev chain.  The caller (an
3144  * ioctl handler calling blocking_notifier_call_chain) holds the necessary
3145  * locks for us to safely manipulate the slave devices (RTNL lock,
3146  * dev_probe_lock).
3147  */
3148 static int bond_netdev_event(struct notifier_block *this,
3149 			     unsigned long event, void *ptr)
3150 {
3151 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
3152 
3153 	netdev_dbg(event_dev, "event: %lx\n", event);
3154 
3155 	if (!(event_dev->priv_flags & IFF_BONDING))
3156 		return NOTIFY_DONE;
3157 
3158 	if (event_dev->flags & IFF_MASTER) {
3159 		netdev_dbg(event_dev, "IFF_MASTER\n");
3160 		return bond_master_netdev_event(event, event_dev);
3161 	}
3162 
3163 	if (event_dev->flags & IFF_SLAVE) {
3164 		netdev_dbg(event_dev, "IFF_SLAVE\n");
3165 		return bond_slave_netdev_event(event, event_dev);
3166 	}
3167 
3168 	return NOTIFY_DONE;
3169 }
3170 
3171 static struct notifier_block bond_netdev_notifier = {
3172 	.notifier_call = bond_netdev_event,
3173 };
3174 
3175 /*---------------------------- Hashing Policies -----------------------------*/
3176 
3177 /* L2 hash helper */
3178 static inline u32 bond_eth_hash(struct sk_buff *skb)
3179 {
3180 	struct ethhdr *ep, hdr_tmp;
3181 
3182 	ep = skb_header_pointer(skb, 0, sizeof(hdr_tmp), &hdr_tmp);
3183 	if (ep)
3184 		return ep->h_dest[5] ^ ep->h_source[5] ^ ep->h_proto;
3185 	return 0;
3186 }
3187 
3188 /* Extract the appropriate headers based on bond's xmit policy */
3189 static bool bond_flow_dissect(struct bonding *bond, struct sk_buff *skb,
3190 			      struct flow_keys *fk)
3191 {
3192 	const struct ipv6hdr *iph6;
3193 	const struct iphdr *iph;
3194 	int noff, proto = -1;
3195 
3196 	if (bond->params.xmit_policy > BOND_XMIT_POLICY_LAYER23)
3197 		return skb_flow_dissect_flow_keys(skb, fk, 0);
3198 
3199 	fk->ports.ports = 0;
3200 	noff = skb_network_offset(skb);
3201 	if (skb->protocol == htons(ETH_P_IP)) {
3202 		if (unlikely(!pskb_may_pull(skb, noff + sizeof(*iph))))
3203 			return false;
3204 		iph = ip_hdr(skb);
3205 		iph_to_flow_copy_v4addrs(fk, iph);
3206 		noff += iph->ihl << 2;
3207 		if (!ip_is_fragment(iph))
3208 			proto = iph->protocol;
3209 	} else if (skb->protocol == htons(ETH_P_IPV6)) {
3210 		if (unlikely(!pskb_may_pull(skb, noff + sizeof(*iph6))))
3211 			return false;
3212 		iph6 = ipv6_hdr(skb);
3213 		iph_to_flow_copy_v6addrs(fk, iph6);
3214 		noff += sizeof(*iph6);
3215 		proto = iph6->nexthdr;
3216 	} else {
3217 		return false;
3218 	}
3219 	if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER34 && proto >= 0)
3220 		fk->ports.ports = skb_flow_get_ports(skb, noff, proto);
3221 
3222 	return true;
3223 }
3224 
3225 /**
3226  * bond_xmit_hash - generate a hash value based on the xmit policy
3227  * @bond: bonding device
3228  * @skb: buffer to use for headers
3229  *
3230  * This function will extract the necessary headers from the skb buffer and use
3231  * them to generate a hash based on the xmit_policy set in the bonding device
3232  */
3233 u32 bond_xmit_hash(struct bonding *bond, struct sk_buff *skb)
3234 {
3235 	struct flow_keys flow;
3236 	u32 hash;
3237 
3238 	if (bond->params.xmit_policy == BOND_XMIT_POLICY_ENCAP34 &&
3239 	    skb->l4_hash)
3240 		return skb->hash;
3241 
3242 	if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER2 ||
3243 	    !bond_flow_dissect(bond, skb, &flow))
3244 		return bond_eth_hash(skb);
3245 
3246 	if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER23 ||
3247 	    bond->params.xmit_policy == BOND_XMIT_POLICY_ENCAP23)
3248 		hash = bond_eth_hash(skb);
3249 	else
3250 		hash = (__force u32)flow.ports.ports;
3251 	hash ^= (__force u32)flow_get_u32_dst(&flow) ^
3252 		(__force u32)flow_get_u32_src(&flow);
3253 	hash ^= (hash >> 16);
3254 	hash ^= (hash >> 8);
3255 
3256 	return hash;
3257 }
3258 
3259 /*-------------------------- Device entry points ----------------------------*/
3260 
3261 void bond_work_init_all(struct bonding *bond)
3262 {
3263 	INIT_DELAYED_WORK(&bond->mcast_work,
3264 			  bond_resend_igmp_join_requests_delayed);
3265 	INIT_DELAYED_WORK(&bond->alb_work, bond_alb_monitor);
3266 	INIT_DELAYED_WORK(&bond->mii_work, bond_mii_monitor);
3267 	INIT_DELAYED_WORK(&bond->arp_work, bond_arp_monitor);
3268 	INIT_DELAYED_WORK(&bond->ad_work, bond_3ad_state_machine_handler);
3269 	INIT_DELAYED_WORK(&bond->slave_arr_work, bond_slave_arr_handler);
3270 }
3271 
3272 static void bond_work_cancel_all(struct bonding *bond)
3273 {
3274 	cancel_delayed_work_sync(&bond->mii_work);
3275 	cancel_delayed_work_sync(&bond->arp_work);
3276 	cancel_delayed_work_sync(&bond->alb_work);
3277 	cancel_delayed_work_sync(&bond->ad_work);
3278 	cancel_delayed_work_sync(&bond->mcast_work);
3279 	cancel_delayed_work_sync(&bond->slave_arr_work);
3280 }
3281 
3282 static int bond_open(struct net_device *bond_dev)
3283 {
3284 	struct bonding *bond = netdev_priv(bond_dev);
3285 	struct list_head *iter;
3286 	struct slave *slave;
3287 
3288 	/* reset slave->backup and slave->inactive */
3289 	if (bond_has_slaves(bond)) {
3290 		bond_for_each_slave(bond, slave, iter) {
3291 			if (bond_uses_primary(bond) &&
3292 			    slave != rcu_access_pointer(bond->curr_active_slave)) {
3293 				bond_set_slave_inactive_flags(slave,
3294 							      BOND_SLAVE_NOTIFY_NOW);
3295 			} else if (BOND_MODE(bond) != BOND_MODE_8023AD) {
3296 				bond_set_slave_active_flags(slave,
3297 							    BOND_SLAVE_NOTIFY_NOW);
3298 			}
3299 		}
3300 	}
3301 
3302 	if (bond_is_lb(bond)) {
3303 		/* bond_alb_initialize must be called before the timer
3304 		 * is started.
3305 		 */
3306 		if (bond_alb_initialize(bond, (BOND_MODE(bond) == BOND_MODE_ALB)))
3307 			return -ENOMEM;
3308 		if (bond->params.tlb_dynamic_lb)
3309 			queue_delayed_work(bond->wq, &bond->alb_work, 0);
3310 	}
3311 
3312 	if (bond->params.miimon)  /* link check interval, in milliseconds. */
3313 		queue_delayed_work(bond->wq, &bond->mii_work, 0);
3314 
3315 	if (bond->params.arp_interval) {  /* arp interval, in milliseconds. */
3316 		queue_delayed_work(bond->wq, &bond->arp_work, 0);
3317 		bond->recv_probe = bond_arp_rcv;
3318 	}
3319 
3320 	if (BOND_MODE(bond) == BOND_MODE_8023AD) {
3321 		queue_delayed_work(bond->wq, &bond->ad_work, 0);
3322 		/* register to receive LACPDUs */
3323 		bond->recv_probe = bond_3ad_lacpdu_recv;
3324 		bond_3ad_initiate_agg_selection(bond, 1);
3325 	}
3326 
3327 	if (bond_mode_uses_xmit_hash(bond))
3328 		bond_update_slave_arr(bond, NULL);
3329 
3330 	return 0;
3331 }
3332 
3333 static int bond_close(struct net_device *bond_dev)
3334 {
3335 	struct bonding *bond = netdev_priv(bond_dev);
3336 
3337 	bond_work_cancel_all(bond);
3338 	bond->send_peer_notif = 0;
3339 	if (bond_is_lb(bond))
3340 		bond_alb_deinitialize(bond);
3341 	bond->recv_probe = NULL;
3342 
3343 	return 0;
3344 }
3345 
3346 /* fold stats, assuming all rtnl_link_stats64 fields are u64, but
3347  * that some drivers can provide 32bit values only.
3348  */
3349 static void bond_fold_stats(struct rtnl_link_stats64 *_res,
3350 			    const struct rtnl_link_stats64 *_new,
3351 			    const struct rtnl_link_stats64 *_old)
3352 {
3353 	const u64 *new = (const u64 *)_new;
3354 	const u64 *old = (const u64 *)_old;
3355 	u64 *res = (u64 *)_res;
3356 	int i;
3357 
3358 	for (i = 0; i < sizeof(*_res) / sizeof(u64); i++) {
3359 		u64 nv = new[i];
3360 		u64 ov = old[i];
3361 		s64 delta = nv - ov;
3362 
3363 		/* detects if this particular field is 32bit only */
3364 		if (((nv | ov) >> 32) == 0)
3365 			delta = (s64)(s32)((u32)nv - (u32)ov);
3366 
3367 		/* filter anomalies, some drivers reset their stats
3368 		 * at down/up events.
3369 		 */
3370 		if (delta > 0)
3371 			res[i] += delta;
3372 	}
3373 }
3374 
3375 static void bond_get_stats(struct net_device *bond_dev,
3376 			   struct rtnl_link_stats64 *stats)
3377 {
3378 	struct bonding *bond = netdev_priv(bond_dev);
3379 	struct rtnl_link_stats64 temp;
3380 	struct list_head *iter;
3381 	struct slave *slave;
3382 
3383 	spin_lock(&bond->stats_lock);
3384 	memcpy(stats, &bond->bond_stats, sizeof(*stats));
3385 
3386 	rcu_read_lock();
3387 	bond_for_each_slave_rcu(bond, slave, iter) {
3388 		const struct rtnl_link_stats64 *new =
3389 			dev_get_stats(slave->dev, &temp);
3390 
3391 		bond_fold_stats(stats, new, &slave->slave_stats);
3392 
3393 		/* save off the slave stats for the next run */
3394 		memcpy(&slave->slave_stats, new, sizeof(*new));
3395 	}
3396 	rcu_read_unlock();
3397 
3398 	memcpy(&bond->bond_stats, stats, sizeof(*stats));
3399 	spin_unlock(&bond->stats_lock);
3400 }
3401 
3402 static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd)
3403 {
3404 	struct bonding *bond = netdev_priv(bond_dev);
3405 	struct net_device *slave_dev = NULL;
3406 	struct ifbond k_binfo;
3407 	struct ifbond __user *u_binfo = NULL;
3408 	struct ifslave k_sinfo;
3409 	struct ifslave __user *u_sinfo = NULL;
3410 	struct mii_ioctl_data *mii = NULL;
3411 	struct bond_opt_value newval;
3412 	struct net *net;
3413 	int res = 0;
3414 
3415 	netdev_dbg(bond_dev, "bond_ioctl: cmd=%d\n", cmd);
3416 
3417 	switch (cmd) {
3418 	case SIOCGMIIPHY:
3419 		mii = if_mii(ifr);
3420 		if (!mii)
3421 			return -EINVAL;
3422 
3423 		mii->phy_id = 0;
3424 		/* Fall Through */
3425 	case SIOCGMIIREG:
3426 		/* We do this again just in case we were called by SIOCGMIIREG
3427 		 * instead of SIOCGMIIPHY.
3428 		 */
3429 		mii = if_mii(ifr);
3430 		if (!mii)
3431 			return -EINVAL;
3432 
3433 		if (mii->reg_num == 1) {
3434 			mii->val_out = 0;
3435 			if (netif_carrier_ok(bond->dev))
3436 				mii->val_out = BMSR_LSTATUS;
3437 		}
3438 
3439 		return 0;
3440 	case BOND_INFO_QUERY_OLD:
3441 	case SIOCBONDINFOQUERY:
3442 		u_binfo = (struct ifbond __user *)ifr->ifr_data;
3443 
3444 		if (copy_from_user(&k_binfo, u_binfo, sizeof(ifbond)))
3445 			return -EFAULT;
3446 
3447 		bond_info_query(bond_dev, &k_binfo);
3448 		if (copy_to_user(u_binfo, &k_binfo, sizeof(ifbond)))
3449 			return -EFAULT;
3450 
3451 		return 0;
3452 	case BOND_SLAVE_INFO_QUERY_OLD:
3453 	case SIOCBONDSLAVEINFOQUERY:
3454 		u_sinfo = (struct ifslave __user *)ifr->ifr_data;
3455 
3456 		if (copy_from_user(&k_sinfo, u_sinfo, sizeof(ifslave)))
3457 			return -EFAULT;
3458 
3459 		res = bond_slave_info_query(bond_dev, &k_sinfo);
3460 		if (res == 0 &&
3461 		    copy_to_user(u_sinfo, &k_sinfo, sizeof(ifslave)))
3462 			return -EFAULT;
3463 
3464 		return res;
3465 	default:
3466 		break;
3467 	}
3468 
3469 	net = dev_net(bond_dev);
3470 
3471 	if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
3472 		return -EPERM;
3473 
3474 	slave_dev = __dev_get_by_name(net, ifr->ifr_slave);
3475 
3476 	netdev_dbg(bond_dev, "slave_dev=%p:\n", slave_dev);
3477 
3478 	if (!slave_dev)
3479 		return -ENODEV;
3480 
3481 	netdev_dbg(bond_dev, "slave_dev->name=%s:\n", slave_dev->name);
3482 	switch (cmd) {
3483 	case BOND_ENSLAVE_OLD:
3484 	case SIOCBONDENSLAVE:
3485 		res = bond_enslave(bond_dev, slave_dev);
3486 		break;
3487 	case BOND_RELEASE_OLD:
3488 	case SIOCBONDRELEASE:
3489 		res = bond_release(bond_dev, slave_dev);
3490 		break;
3491 	case BOND_SETHWADDR_OLD:
3492 	case SIOCBONDSETHWADDR:
3493 		bond_set_dev_addr(bond_dev, slave_dev);
3494 		res = 0;
3495 		break;
3496 	case BOND_CHANGE_ACTIVE_OLD:
3497 	case SIOCBONDCHANGEACTIVE:
3498 		bond_opt_initstr(&newval, slave_dev->name);
3499 		res = __bond_opt_set_notify(bond, BOND_OPT_ACTIVE_SLAVE,
3500 					    &newval);
3501 		break;
3502 	default:
3503 		res = -EOPNOTSUPP;
3504 	}
3505 
3506 	return res;
3507 }
3508 
3509 static void bond_change_rx_flags(struct net_device *bond_dev, int change)
3510 {
3511 	struct bonding *bond = netdev_priv(bond_dev);
3512 
3513 	if (change & IFF_PROMISC)
3514 		bond_set_promiscuity(bond,
3515 				     bond_dev->flags & IFF_PROMISC ? 1 : -1);
3516 
3517 	if (change & IFF_ALLMULTI)
3518 		bond_set_allmulti(bond,
3519 				  bond_dev->flags & IFF_ALLMULTI ? 1 : -1);
3520 }
3521 
3522 static void bond_set_rx_mode(struct net_device *bond_dev)
3523 {
3524 	struct bonding *bond = netdev_priv(bond_dev);
3525 	struct list_head *iter;
3526 	struct slave *slave;
3527 
3528 	rcu_read_lock();
3529 	if (bond_uses_primary(bond)) {
3530 		slave = rcu_dereference(bond->curr_active_slave);
3531 		if (slave) {
3532 			dev_uc_sync(slave->dev, bond_dev);
3533 			dev_mc_sync(slave->dev, bond_dev);
3534 		}
3535 	} else {
3536 		bond_for_each_slave_rcu(bond, slave, iter) {
3537 			dev_uc_sync_multiple(slave->dev, bond_dev);
3538 			dev_mc_sync_multiple(slave->dev, bond_dev);
3539 		}
3540 	}
3541 	rcu_read_unlock();
3542 }
3543 
3544 static int bond_neigh_init(struct neighbour *n)
3545 {
3546 	struct bonding *bond = netdev_priv(n->dev);
3547 	const struct net_device_ops *slave_ops;
3548 	struct neigh_parms parms;
3549 	struct slave *slave;
3550 	int ret;
3551 
3552 	slave = bond_first_slave(bond);
3553 	if (!slave)
3554 		return 0;
3555 	slave_ops = slave->dev->netdev_ops;
3556 	if (!slave_ops->ndo_neigh_setup)
3557 		return 0;
3558 
3559 	parms.neigh_setup = NULL;
3560 	parms.neigh_cleanup = NULL;
3561 	ret = slave_ops->ndo_neigh_setup(slave->dev, &parms);
3562 	if (ret)
3563 		return ret;
3564 
3565 	/* Assign slave's neigh_cleanup to neighbour in case cleanup is called
3566 	 * after the last slave has been detached.  Assumes that all slaves
3567 	 * utilize the same neigh_cleanup (true at this writing as only user
3568 	 * is ipoib).
3569 	 */
3570 	n->parms->neigh_cleanup = parms.neigh_cleanup;
3571 
3572 	if (!parms.neigh_setup)
3573 		return 0;
3574 
3575 	return parms.neigh_setup(n);
3576 }
3577 
3578 /* The bonding ndo_neigh_setup is called at init time beofre any
3579  * slave exists. So we must declare proxy setup function which will
3580  * be used at run time to resolve the actual slave neigh param setup.
3581  *
3582  * It's also called by master devices (such as vlans) to setup their
3583  * underlying devices. In that case - do nothing, we're already set up from
3584  * our init.
3585  */
3586 static int bond_neigh_setup(struct net_device *dev,
3587 			    struct neigh_parms *parms)
3588 {
3589 	/* modify only our neigh_parms */
3590 	if (parms->dev == dev)
3591 		parms->neigh_setup = bond_neigh_init;
3592 
3593 	return 0;
3594 }
3595 
3596 /* Change the MTU of all of a master's slaves to match the master */
3597 static int bond_change_mtu(struct net_device *bond_dev, int new_mtu)
3598 {
3599 	struct bonding *bond = netdev_priv(bond_dev);
3600 	struct slave *slave, *rollback_slave;
3601 	struct list_head *iter;
3602 	int res = 0;
3603 
3604 	netdev_dbg(bond_dev, "bond=%p, new_mtu=%d\n", bond, new_mtu);
3605 
3606 	bond_for_each_slave(bond, slave, iter) {
3607 		netdev_dbg(bond_dev, "s %p c_m %p\n",
3608 			   slave, slave->dev->netdev_ops->ndo_change_mtu);
3609 
3610 		res = dev_set_mtu(slave->dev, new_mtu);
3611 
3612 		if (res) {
3613 			/* If we failed to set the slave's mtu to the new value
3614 			 * we must abort the operation even in ACTIVE_BACKUP
3615 			 * mode, because if we allow the backup slaves to have
3616 			 * different mtu values than the active slave we'll
3617 			 * need to change their mtu when doing a failover. That
3618 			 * means changing their mtu from timer context, which
3619 			 * is probably not a good idea.
3620 			 */
3621 			netdev_dbg(bond_dev, "err %d %s\n", res,
3622 				   slave->dev->name);
3623 			goto unwind;
3624 		}
3625 	}
3626 
3627 	bond_dev->mtu = new_mtu;
3628 
3629 	return 0;
3630 
3631 unwind:
3632 	/* unwind from head to the slave that failed */
3633 	bond_for_each_slave(bond, rollback_slave, iter) {
3634 		int tmp_res;
3635 
3636 		if (rollback_slave == slave)
3637 			break;
3638 
3639 		tmp_res = dev_set_mtu(rollback_slave->dev, bond_dev->mtu);
3640 		if (tmp_res) {
3641 			netdev_dbg(bond_dev, "unwind err %d dev %s\n",
3642 				   tmp_res, rollback_slave->dev->name);
3643 		}
3644 	}
3645 
3646 	return res;
3647 }
3648 
3649 /* Change HW address
3650  *
3651  * Note that many devices must be down to change the HW address, and
3652  * downing the master releases all slaves.  We can make bonds full of
3653  * bonding devices to test this, however.
3654  */
3655 static int bond_set_mac_address(struct net_device *bond_dev, void *addr)
3656 {
3657 	struct bonding *bond = netdev_priv(bond_dev);
3658 	struct slave *slave, *rollback_slave;
3659 	struct sockaddr_storage *ss = addr, tmp_ss;
3660 	struct list_head *iter;
3661 	int res = 0;
3662 
3663 	if (BOND_MODE(bond) == BOND_MODE_ALB)
3664 		return bond_alb_set_mac_address(bond_dev, addr);
3665 
3666 
3667 	netdev_dbg(bond_dev, "bond=%p\n", bond);
3668 
3669 	/* If fail_over_mac is enabled, do nothing and return success.
3670 	 * Returning an error causes ifenslave to fail.
3671 	 */
3672 	if (bond->params.fail_over_mac &&
3673 	    BOND_MODE(bond) == BOND_MODE_ACTIVEBACKUP)
3674 		return 0;
3675 
3676 	if (!is_valid_ether_addr(ss->__data))
3677 		return -EADDRNOTAVAIL;
3678 
3679 	bond_for_each_slave(bond, slave, iter) {
3680 		netdev_dbg(bond_dev, "slave %p %s\n", slave, slave->dev->name);
3681 		res = dev_set_mac_address(slave->dev, addr);
3682 		if (res) {
3683 			/* TODO: consider downing the slave
3684 			 * and retry ?
3685 			 * User should expect communications
3686 			 * breakage anyway until ARP finish
3687 			 * updating, so...
3688 			 */
3689 			netdev_dbg(bond_dev, "err %d %s\n", res, slave->dev->name);
3690 			goto unwind;
3691 		}
3692 	}
3693 
3694 	/* success */
3695 	memcpy(bond_dev->dev_addr, ss->__data, bond_dev->addr_len);
3696 	return 0;
3697 
3698 unwind:
3699 	memcpy(tmp_ss.__data, bond_dev->dev_addr, bond_dev->addr_len);
3700 	tmp_ss.ss_family = bond_dev->type;
3701 
3702 	/* unwind from head to the slave that failed */
3703 	bond_for_each_slave(bond, rollback_slave, iter) {
3704 		int tmp_res;
3705 
3706 		if (rollback_slave == slave)
3707 			break;
3708 
3709 		tmp_res = dev_set_mac_address(rollback_slave->dev,
3710 					      (struct sockaddr *)&tmp_ss);
3711 		if (tmp_res) {
3712 			netdev_dbg(bond_dev, "unwind err %d dev %s\n",
3713 				   tmp_res, rollback_slave->dev->name);
3714 		}
3715 	}
3716 
3717 	return res;
3718 }
3719 
3720 /**
3721  * bond_xmit_slave_id - transmit skb through slave with slave_id
3722  * @bond: bonding device that is transmitting
3723  * @skb: buffer to transmit
3724  * @slave_id: slave id up to slave_cnt-1 through which to transmit
3725  *
3726  * This function tries to transmit through slave with slave_id but in case
3727  * it fails, it tries to find the first available slave for transmission.
3728  * The skb is consumed in all cases, thus the function is void.
3729  */
3730 static void bond_xmit_slave_id(struct bonding *bond, struct sk_buff *skb, int slave_id)
3731 {
3732 	struct list_head *iter;
3733 	struct slave *slave;
3734 	int i = slave_id;
3735 
3736 	/* Here we start from the slave with slave_id */
3737 	bond_for_each_slave_rcu(bond, slave, iter) {
3738 		if (--i < 0) {
3739 			if (bond_slave_can_tx(slave)) {
3740 				bond_dev_queue_xmit(bond, skb, slave->dev);
3741 				return;
3742 			}
3743 		}
3744 	}
3745 
3746 	/* Here we start from the first slave up to slave_id */
3747 	i = slave_id;
3748 	bond_for_each_slave_rcu(bond, slave, iter) {
3749 		if (--i < 0)
3750 			break;
3751 		if (bond_slave_can_tx(slave)) {
3752 			bond_dev_queue_xmit(bond, skb, slave->dev);
3753 			return;
3754 		}
3755 	}
3756 	/* no slave that can tx has been found */
3757 	bond_tx_drop(bond->dev, skb);
3758 }
3759 
3760 /**
3761  * bond_rr_gen_slave_id - generate slave id based on packets_per_slave
3762  * @bond: bonding device to use
3763  *
3764  * Based on the value of the bonding device's packets_per_slave parameter
3765  * this function generates a slave id, which is usually used as the next
3766  * slave to transmit through.
3767  */
3768 static u32 bond_rr_gen_slave_id(struct bonding *bond)
3769 {
3770 	u32 slave_id;
3771 	struct reciprocal_value reciprocal_packets_per_slave;
3772 	int packets_per_slave = bond->params.packets_per_slave;
3773 
3774 	switch (packets_per_slave) {
3775 	case 0:
3776 		slave_id = prandom_u32();
3777 		break;
3778 	case 1:
3779 		slave_id = bond->rr_tx_counter;
3780 		break;
3781 	default:
3782 		reciprocal_packets_per_slave =
3783 			bond->params.reciprocal_packets_per_slave;
3784 		slave_id = reciprocal_divide(bond->rr_tx_counter,
3785 					     reciprocal_packets_per_slave);
3786 		break;
3787 	}
3788 	bond->rr_tx_counter++;
3789 
3790 	return slave_id;
3791 }
3792 
3793 static int bond_xmit_roundrobin(struct sk_buff *skb, struct net_device *bond_dev)
3794 {
3795 	struct bonding *bond = netdev_priv(bond_dev);
3796 	struct iphdr *iph = ip_hdr(skb);
3797 	struct slave *slave;
3798 	u32 slave_id;
3799 
3800 	/* Start with the curr_active_slave that joined the bond as the
3801 	 * default for sending IGMP traffic.  For failover purposes one
3802 	 * needs to maintain some consistency for the interface that will
3803 	 * send the join/membership reports.  The curr_active_slave found
3804 	 * will send all of this type of traffic.
3805 	 */
3806 	if (iph->protocol == IPPROTO_IGMP && skb->protocol == htons(ETH_P_IP)) {
3807 		slave = rcu_dereference(bond->curr_active_slave);
3808 		if (slave)
3809 			bond_dev_queue_xmit(bond, skb, slave->dev);
3810 		else
3811 			bond_xmit_slave_id(bond, skb, 0);
3812 	} else {
3813 		int slave_cnt = READ_ONCE(bond->slave_cnt);
3814 
3815 		if (likely(slave_cnt)) {
3816 			slave_id = bond_rr_gen_slave_id(bond);
3817 			bond_xmit_slave_id(bond, skb, slave_id % slave_cnt);
3818 		} else {
3819 			bond_tx_drop(bond_dev, skb);
3820 		}
3821 	}
3822 
3823 	return NETDEV_TX_OK;
3824 }
3825 
3826 /* In active-backup mode, we know that bond->curr_active_slave is always valid if
3827  * the bond has a usable interface.
3828  */
3829 static int bond_xmit_activebackup(struct sk_buff *skb, struct net_device *bond_dev)
3830 {
3831 	struct bonding *bond = netdev_priv(bond_dev);
3832 	struct slave *slave;
3833 
3834 	slave = rcu_dereference(bond->curr_active_slave);
3835 	if (slave)
3836 		bond_dev_queue_xmit(bond, skb, slave->dev);
3837 	else
3838 		bond_tx_drop(bond_dev, skb);
3839 
3840 	return NETDEV_TX_OK;
3841 }
3842 
3843 /* Use this to update slave_array when (a) it's not appropriate to update
3844  * slave_array right away (note that update_slave_array() may sleep)
3845  * and / or (b) RTNL is not held.
3846  */
3847 void bond_slave_arr_work_rearm(struct bonding *bond, unsigned long delay)
3848 {
3849 	queue_delayed_work(bond->wq, &bond->slave_arr_work, delay);
3850 }
3851 
3852 /* Slave array work handler. Holds only RTNL */
3853 static void bond_slave_arr_handler(struct work_struct *work)
3854 {
3855 	struct bonding *bond = container_of(work, struct bonding,
3856 					    slave_arr_work.work);
3857 	int ret;
3858 
3859 	if (!rtnl_trylock())
3860 		goto err;
3861 
3862 	ret = bond_update_slave_arr(bond, NULL);
3863 	rtnl_unlock();
3864 	if (ret) {
3865 		pr_warn_ratelimited("Failed to update slave array from WT\n");
3866 		goto err;
3867 	}
3868 	return;
3869 
3870 err:
3871 	bond_slave_arr_work_rearm(bond, 1);
3872 }
3873 
3874 /* Build the usable slaves array in control path for modes that use xmit-hash
3875  * to determine the slave interface -
3876  * (a) BOND_MODE_8023AD
3877  * (b) BOND_MODE_XOR
3878  * (c) BOND_MODE_TLB && tlb_dynamic_lb == 0
3879  *
3880  * The caller is expected to hold RTNL only and NO other lock!
3881  */
3882 int bond_update_slave_arr(struct bonding *bond, struct slave *skipslave)
3883 {
3884 	struct slave *slave;
3885 	struct list_head *iter;
3886 	struct bond_up_slave *new_arr, *old_arr;
3887 	int agg_id = 0;
3888 	int ret = 0;
3889 
3890 #ifdef CONFIG_LOCKDEP
3891 	WARN_ON(lockdep_is_held(&bond->mode_lock));
3892 #endif
3893 
3894 	new_arr = kzalloc(offsetof(struct bond_up_slave, arr[bond->slave_cnt]),
3895 			  GFP_KERNEL);
3896 	if (!new_arr) {
3897 		ret = -ENOMEM;
3898 		pr_err("Failed to build slave-array.\n");
3899 		goto out;
3900 	}
3901 	if (BOND_MODE(bond) == BOND_MODE_8023AD) {
3902 		struct ad_info ad_info;
3903 
3904 		if (bond_3ad_get_active_agg_info(bond, &ad_info)) {
3905 			pr_debug("bond_3ad_get_active_agg_info failed\n");
3906 			kfree_rcu(new_arr, rcu);
3907 			/* No active aggragator means it's not safe to use
3908 			 * the previous array.
3909 			 */
3910 			old_arr = rtnl_dereference(bond->slave_arr);
3911 			if (old_arr) {
3912 				RCU_INIT_POINTER(bond->slave_arr, NULL);
3913 				kfree_rcu(old_arr, rcu);
3914 			}
3915 			goto out;
3916 		}
3917 		agg_id = ad_info.aggregator_id;
3918 	}
3919 	bond_for_each_slave(bond, slave, iter) {
3920 		if (BOND_MODE(bond) == BOND_MODE_8023AD) {
3921 			struct aggregator *agg;
3922 
3923 			agg = SLAVE_AD_INFO(slave)->port.aggregator;
3924 			if (!agg || agg->aggregator_identifier != agg_id)
3925 				continue;
3926 		}
3927 		if (!bond_slave_can_tx(slave))
3928 			continue;
3929 		if (skipslave == slave)
3930 			continue;
3931 		new_arr->arr[new_arr->count++] = slave;
3932 	}
3933 
3934 	old_arr = rtnl_dereference(bond->slave_arr);
3935 	rcu_assign_pointer(bond->slave_arr, new_arr);
3936 	if (old_arr)
3937 		kfree_rcu(old_arr, rcu);
3938 out:
3939 	if (ret != 0 && skipslave) {
3940 		int idx;
3941 
3942 		/* Rare situation where caller has asked to skip a specific
3943 		 * slave but allocation failed (most likely!). BTW this is
3944 		 * only possible when the call is initiated from
3945 		 * __bond_release_one(). In this situation; overwrite the
3946 		 * skipslave entry in the array with the last entry from the
3947 		 * array to avoid a situation where the xmit path may choose
3948 		 * this to-be-skipped slave to send a packet out.
3949 		 */
3950 		old_arr = rtnl_dereference(bond->slave_arr);
3951 		for (idx = 0; idx < old_arr->count; idx++) {
3952 			if (skipslave == old_arr->arr[idx]) {
3953 				old_arr->arr[idx] =
3954 				    old_arr->arr[old_arr->count-1];
3955 				old_arr->count--;
3956 				break;
3957 			}
3958 		}
3959 	}
3960 	return ret;
3961 }
3962 
3963 /* Use this Xmit function for 3AD as well as XOR modes. The current
3964  * usable slave array is formed in the control path. The xmit function
3965  * just calculates hash and sends the packet out.
3966  */
3967 static int bond_3ad_xor_xmit(struct sk_buff *skb, struct net_device *dev)
3968 {
3969 	struct bonding *bond = netdev_priv(dev);
3970 	struct slave *slave;
3971 	struct bond_up_slave *slaves;
3972 	unsigned int count;
3973 
3974 	slaves = rcu_dereference(bond->slave_arr);
3975 	count = slaves ? READ_ONCE(slaves->count) : 0;
3976 	if (likely(count)) {
3977 		slave = slaves->arr[bond_xmit_hash(bond, skb) % count];
3978 		bond_dev_queue_xmit(bond, skb, slave->dev);
3979 	} else {
3980 		bond_tx_drop(dev, skb);
3981 	}
3982 
3983 	return NETDEV_TX_OK;
3984 }
3985 
3986 /* in broadcast mode, we send everything to all usable interfaces. */
3987 static int bond_xmit_broadcast(struct sk_buff *skb, struct net_device *bond_dev)
3988 {
3989 	struct bonding *bond = netdev_priv(bond_dev);
3990 	struct slave *slave = NULL;
3991 	struct list_head *iter;
3992 
3993 	bond_for_each_slave_rcu(bond, slave, iter) {
3994 		if (bond_is_last_slave(bond, slave))
3995 			break;
3996 		if (bond_slave_is_up(slave) && slave->link == BOND_LINK_UP) {
3997 			struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
3998 
3999 			if (!skb2) {
4000 				net_err_ratelimited("%s: Error: %s: skb_clone() failed\n",
4001 						    bond_dev->name, __func__);
4002 				continue;
4003 			}
4004 			bond_dev_queue_xmit(bond, skb2, slave->dev);
4005 		}
4006 	}
4007 	if (slave && bond_slave_is_up(slave) && slave->link == BOND_LINK_UP)
4008 		bond_dev_queue_xmit(bond, skb, slave->dev);
4009 	else
4010 		bond_tx_drop(bond_dev, skb);
4011 
4012 	return NETDEV_TX_OK;
4013 }
4014 
4015 /*------------------------- Device initialization ---------------------------*/
4016 
4017 /* Lookup the slave that corresponds to a qid */
4018 static inline int bond_slave_override(struct bonding *bond,
4019 				      struct sk_buff *skb)
4020 {
4021 	struct slave *slave = NULL;
4022 	struct list_head *iter;
4023 
4024 	if (!skb->queue_mapping)
4025 		return 1;
4026 
4027 	/* Find out if any slaves have the same mapping as this skb. */
4028 	bond_for_each_slave_rcu(bond, slave, iter) {
4029 		if (slave->queue_id == skb->queue_mapping) {
4030 			if (bond_slave_is_up(slave) &&
4031 			    slave->link == BOND_LINK_UP) {
4032 				bond_dev_queue_xmit(bond, skb, slave->dev);
4033 				return 0;
4034 			}
4035 			/* If the slave isn't UP, use default transmit policy. */
4036 			break;
4037 		}
4038 	}
4039 
4040 	return 1;
4041 }
4042 
4043 
4044 static u16 bond_select_queue(struct net_device *dev, struct sk_buff *skb,
4045 			     void *accel_priv, select_queue_fallback_t fallback)
4046 {
4047 	/* This helper function exists to help dev_pick_tx get the correct
4048 	 * destination queue.  Using a helper function skips a call to
4049 	 * skb_tx_hash and will put the skbs in the queue we expect on their
4050 	 * way down to the bonding driver.
4051 	 */
4052 	u16 txq = skb_rx_queue_recorded(skb) ? skb_get_rx_queue(skb) : 0;
4053 
4054 	/* Save the original txq to restore before passing to the driver */
4055 	qdisc_skb_cb(skb)->slave_dev_queue_mapping = skb->queue_mapping;
4056 
4057 	if (unlikely(txq >= dev->real_num_tx_queues)) {
4058 		do {
4059 			txq -= dev->real_num_tx_queues;
4060 		} while (txq >= dev->real_num_tx_queues);
4061 	}
4062 	return txq;
4063 }
4064 
4065 static netdev_tx_t __bond_start_xmit(struct sk_buff *skb, struct net_device *dev)
4066 {
4067 	struct bonding *bond = netdev_priv(dev);
4068 
4069 	if (bond_should_override_tx_queue(bond) &&
4070 	    !bond_slave_override(bond, skb))
4071 		return NETDEV_TX_OK;
4072 
4073 	switch (BOND_MODE(bond)) {
4074 	case BOND_MODE_ROUNDROBIN:
4075 		return bond_xmit_roundrobin(skb, dev);
4076 	case BOND_MODE_ACTIVEBACKUP:
4077 		return bond_xmit_activebackup(skb, dev);
4078 	case BOND_MODE_8023AD:
4079 	case BOND_MODE_XOR:
4080 		return bond_3ad_xor_xmit(skb, dev);
4081 	case BOND_MODE_BROADCAST:
4082 		return bond_xmit_broadcast(skb, dev);
4083 	case BOND_MODE_ALB:
4084 		return bond_alb_xmit(skb, dev);
4085 	case BOND_MODE_TLB:
4086 		return bond_tlb_xmit(skb, dev);
4087 	default:
4088 		/* Should never happen, mode already checked */
4089 		netdev_err(dev, "Unknown bonding mode %d\n", BOND_MODE(bond));
4090 		WARN_ON_ONCE(1);
4091 		bond_tx_drop(dev, skb);
4092 		return NETDEV_TX_OK;
4093 	}
4094 }
4095 
4096 static netdev_tx_t bond_start_xmit(struct sk_buff *skb, struct net_device *dev)
4097 {
4098 	struct bonding *bond = netdev_priv(dev);
4099 	netdev_tx_t ret = NETDEV_TX_OK;
4100 
4101 	/* If we risk deadlock from transmitting this in the
4102 	 * netpoll path, tell netpoll to queue the frame for later tx
4103 	 */
4104 	if (unlikely(is_netpoll_tx_blocked(dev)))
4105 		return NETDEV_TX_BUSY;
4106 
4107 	rcu_read_lock();
4108 	if (bond_has_slaves(bond))
4109 		ret = __bond_start_xmit(skb, dev);
4110 	else
4111 		bond_tx_drop(dev, skb);
4112 	rcu_read_unlock();
4113 
4114 	return ret;
4115 }
4116 
4117 static int bond_ethtool_get_link_ksettings(struct net_device *bond_dev,
4118 					   struct ethtool_link_ksettings *cmd)
4119 {
4120 	struct bonding *bond = netdev_priv(bond_dev);
4121 	unsigned long speed = 0;
4122 	struct list_head *iter;
4123 	struct slave *slave;
4124 
4125 	cmd->base.duplex = DUPLEX_UNKNOWN;
4126 	cmd->base.port = PORT_OTHER;
4127 
4128 	/* Since bond_slave_can_tx returns false for all inactive or down slaves, we
4129 	 * do not need to check mode.  Though link speed might not represent
4130 	 * the true receive or transmit bandwidth (not all modes are symmetric)
4131 	 * this is an accurate maximum.
4132 	 */
4133 	bond_for_each_slave(bond, slave, iter) {
4134 		if (bond_slave_can_tx(slave)) {
4135 			if (slave->speed != SPEED_UNKNOWN)
4136 				speed += slave->speed;
4137 			if (cmd->base.duplex == DUPLEX_UNKNOWN &&
4138 			    slave->duplex != DUPLEX_UNKNOWN)
4139 				cmd->base.duplex = slave->duplex;
4140 		}
4141 	}
4142 	cmd->base.speed = speed ? : SPEED_UNKNOWN;
4143 
4144 	return 0;
4145 }
4146 
4147 static void bond_ethtool_get_drvinfo(struct net_device *bond_dev,
4148 				     struct ethtool_drvinfo *drvinfo)
4149 {
4150 	strlcpy(drvinfo->driver, DRV_NAME, sizeof(drvinfo->driver));
4151 	strlcpy(drvinfo->version, DRV_VERSION, sizeof(drvinfo->version));
4152 	snprintf(drvinfo->fw_version, sizeof(drvinfo->fw_version), "%d",
4153 		 BOND_ABI_VERSION);
4154 }
4155 
4156 static const struct ethtool_ops bond_ethtool_ops = {
4157 	.get_drvinfo		= bond_ethtool_get_drvinfo,
4158 	.get_link		= ethtool_op_get_link,
4159 	.get_link_ksettings	= bond_ethtool_get_link_ksettings,
4160 };
4161 
4162 static const struct net_device_ops bond_netdev_ops = {
4163 	.ndo_init		= bond_init,
4164 	.ndo_uninit		= bond_uninit,
4165 	.ndo_open		= bond_open,
4166 	.ndo_stop		= bond_close,
4167 	.ndo_start_xmit		= bond_start_xmit,
4168 	.ndo_select_queue	= bond_select_queue,
4169 	.ndo_get_stats64	= bond_get_stats,
4170 	.ndo_do_ioctl		= bond_do_ioctl,
4171 	.ndo_change_rx_flags	= bond_change_rx_flags,
4172 	.ndo_set_rx_mode	= bond_set_rx_mode,
4173 	.ndo_change_mtu		= bond_change_mtu,
4174 	.ndo_set_mac_address	= bond_set_mac_address,
4175 	.ndo_neigh_setup	= bond_neigh_setup,
4176 	.ndo_vlan_rx_add_vid	= bond_vlan_rx_add_vid,
4177 	.ndo_vlan_rx_kill_vid	= bond_vlan_rx_kill_vid,
4178 #ifdef CONFIG_NET_POLL_CONTROLLER
4179 	.ndo_netpoll_setup	= bond_netpoll_setup,
4180 	.ndo_netpoll_cleanup	= bond_netpoll_cleanup,
4181 	.ndo_poll_controller	= bond_poll_controller,
4182 #endif
4183 	.ndo_add_slave		= bond_enslave,
4184 	.ndo_del_slave		= bond_release,
4185 	.ndo_fix_features	= bond_fix_features,
4186 	.ndo_features_check	= passthru_features_check,
4187 };
4188 
4189 static const struct device_type bond_type = {
4190 	.name = "bond",
4191 };
4192 
4193 static void bond_destructor(struct net_device *bond_dev)
4194 {
4195 	struct bonding *bond = netdev_priv(bond_dev);
4196 	if (bond->wq)
4197 		destroy_workqueue(bond->wq);
4198 }
4199 
4200 void bond_setup(struct net_device *bond_dev)
4201 {
4202 	struct bonding *bond = netdev_priv(bond_dev);
4203 
4204 	spin_lock_init(&bond->mode_lock);
4205 	spin_lock_init(&bond->stats_lock);
4206 	bond->params = bonding_defaults;
4207 
4208 	/* Initialize pointers */
4209 	bond->dev = bond_dev;
4210 
4211 	/* Initialize the device entry points */
4212 	ether_setup(bond_dev);
4213 	bond_dev->max_mtu = ETH_MAX_MTU;
4214 	bond_dev->netdev_ops = &bond_netdev_ops;
4215 	bond_dev->ethtool_ops = &bond_ethtool_ops;
4216 
4217 	bond_dev->needs_free_netdev = true;
4218 	bond_dev->priv_destructor = bond_destructor;
4219 
4220 	SET_NETDEV_DEVTYPE(bond_dev, &bond_type);
4221 
4222 	/* Initialize the device options */
4223 	bond_dev->flags |= IFF_MASTER;
4224 	bond_dev->priv_flags |= IFF_BONDING | IFF_UNICAST_FLT | IFF_NO_QUEUE;
4225 	bond_dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
4226 
4227 	/* don't acquire bond device's netif_tx_lock when transmitting */
4228 	bond_dev->features |= NETIF_F_LLTX;
4229 
4230 	/* By default, we declare the bond to be fully
4231 	 * VLAN hardware accelerated capable. Special
4232 	 * care is taken in the various xmit functions
4233 	 * when there are slaves that are not hw accel
4234 	 * capable
4235 	 */
4236 
4237 	/* Don't allow bond devices to change network namespaces. */
4238 	bond_dev->features |= NETIF_F_NETNS_LOCAL;
4239 
4240 	bond_dev->hw_features = BOND_VLAN_FEATURES |
4241 				NETIF_F_HW_VLAN_CTAG_TX |
4242 				NETIF_F_HW_VLAN_CTAG_RX |
4243 				NETIF_F_HW_VLAN_CTAG_FILTER;
4244 
4245 	bond_dev->hw_features |= NETIF_F_GSO_ENCAP_ALL;
4246 	bond_dev->features |= bond_dev->hw_features;
4247 }
4248 
4249 /* Destroy a bonding device.
4250  * Must be under rtnl_lock when this function is called.
4251  */
4252 static void bond_uninit(struct net_device *bond_dev)
4253 {
4254 	struct bonding *bond = netdev_priv(bond_dev);
4255 	struct list_head *iter;
4256 	struct slave *slave;
4257 	struct bond_up_slave *arr;
4258 
4259 	bond_netpoll_cleanup(bond_dev);
4260 
4261 	/* Release the bonded slaves */
4262 	bond_for_each_slave(bond, slave, iter)
4263 		__bond_release_one(bond_dev, slave->dev, true, true);
4264 	netdev_info(bond_dev, "Released all slaves\n");
4265 
4266 	arr = rtnl_dereference(bond->slave_arr);
4267 	if (arr) {
4268 		RCU_INIT_POINTER(bond->slave_arr, NULL);
4269 		kfree_rcu(arr, rcu);
4270 	}
4271 
4272 	list_del(&bond->bond_list);
4273 
4274 	bond_debug_unregister(bond);
4275 }
4276 
4277 /*------------------------- Module initialization ---------------------------*/
4278 
4279 static int bond_check_params(struct bond_params *params)
4280 {
4281 	int arp_validate_value, fail_over_mac_value, primary_reselect_value, i;
4282 	struct bond_opt_value newval;
4283 	const struct bond_opt_value *valptr;
4284 	int arp_all_targets_value = 0;
4285 	u16 ad_actor_sys_prio = 0;
4286 	u16 ad_user_port_key = 0;
4287 	__be32 arp_target[BOND_MAX_ARP_TARGETS] = { 0 };
4288 	int arp_ip_count;
4289 	int bond_mode	= BOND_MODE_ROUNDROBIN;
4290 	int xmit_hashtype = BOND_XMIT_POLICY_LAYER2;
4291 	int lacp_fast = 0;
4292 	int tlb_dynamic_lb;
4293 
4294 	/* Convert string parameters. */
4295 	if (mode) {
4296 		bond_opt_initstr(&newval, mode);
4297 		valptr = bond_opt_parse(bond_opt_get(BOND_OPT_MODE), &newval);
4298 		if (!valptr) {
4299 			pr_err("Error: Invalid bonding mode \"%s\"\n", mode);
4300 			return -EINVAL;
4301 		}
4302 		bond_mode = valptr->value;
4303 	}
4304 
4305 	if (xmit_hash_policy) {
4306 		if ((bond_mode != BOND_MODE_XOR) &&
4307 		    (bond_mode != BOND_MODE_8023AD) &&
4308 		    (bond_mode != BOND_MODE_TLB)) {
4309 			pr_info("xmit_hash_policy param is irrelevant in mode %s\n",
4310 				bond_mode_name(bond_mode));
4311 		} else {
4312 			bond_opt_initstr(&newval, xmit_hash_policy);
4313 			valptr = bond_opt_parse(bond_opt_get(BOND_OPT_XMIT_HASH),
4314 						&newval);
4315 			if (!valptr) {
4316 				pr_err("Error: Invalid xmit_hash_policy \"%s\"\n",
4317 				       xmit_hash_policy);
4318 				return -EINVAL;
4319 			}
4320 			xmit_hashtype = valptr->value;
4321 		}
4322 	}
4323 
4324 	if (lacp_rate) {
4325 		if (bond_mode != BOND_MODE_8023AD) {
4326 			pr_info("lacp_rate param is irrelevant in mode %s\n",
4327 				bond_mode_name(bond_mode));
4328 		} else {
4329 			bond_opt_initstr(&newval, lacp_rate);
4330 			valptr = bond_opt_parse(bond_opt_get(BOND_OPT_LACP_RATE),
4331 						&newval);
4332 			if (!valptr) {
4333 				pr_err("Error: Invalid lacp rate \"%s\"\n",
4334 				       lacp_rate);
4335 				return -EINVAL;
4336 			}
4337 			lacp_fast = valptr->value;
4338 		}
4339 	}
4340 
4341 	if (ad_select) {
4342 		bond_opt_initstr(&newval, ad_select);
4343 		valptr = bond_opt_parse(bond_opt_get(BOND_OPT_AD_SELECT),
4344 					&newval);
4345 		if (!valptr) {
4346 			pr_err("Error: Invalid ad_select \"%s\"\n", ad_select);
4347 			return -EINVAL;
4348 		}
4349 		params->ad_select = valptr->value;
4350 		if (bond_mode != BOND_MODE_8023AD)
4351 			pr_warn("ad_select param only affects 802.3ad mode\n");
4352 	} else {
4353 		params->ad_select = BOND_AD_STABLE;
4354 	}
4355 
4356 	if (max_bonds < 0) {
4357 		pr_warn("Warning: max_bonds (%d) not in range %d-%d, so it was reset to BOND_DEFAULT_MAX_BONDS (%d)\n",
4358 			max_bonds, 0, INT_MAX, BOND_DEFAULT_MAX_BONDS);
4359 		max_bonds = BOND_DEFAULT_MAX_BONDS;
4360 	}
4361 
4362 	if (miimon < 0) {
4363 		pr_warn("Warning: miimon module parameter (%d), not in range 0-%d, so it was reset to 0\n",
4364 			miimon, INT_MAX);
4365 		miimon = 0;
4366 	}
4367 
4368 	if (updelay < 0) {
4369 		pr_warn("Warning: updelay module parameter (%d), not in range 0-%d, so it was reset to 0\n",
4370 			updelay, INT_MAX);
4371 		updelay = 0;
4372 	}
4373 
4374 	if (downdelay < 0) {
4375 		pr_warn("Warning: downdelay module parameter (%d), not in range 0-%d, so it was reset to 0\n",
4376 			downdelay, INT_MAX);
4377 		downdelay = 0;
4378 	}
4379 
4380 	if ((use_carrier != 0) && (use_carrier != 1)) {
4381 		pr_warn("Warning: use_carrier module parameter (%d), not of valid value (0/1), so it was set to 1\n",
4382 			use_carrier);
4383 		use_carrier = 1;
4384 	}
4385 
4386 	if (num_peer_notif < 0 || num_peer_notif > 255) {
4387 		pr_warn("Warning: num_grat_arp/num_unsol_na (%d) not in range 0-255 so it was reset to 1\n",
4388 			num_peer_notif);
4389 		num_peer_notif = 1;
4390 	}
4391 
4392 	/* reset values for 802.3ad/TLB/ALB */
4393 	if (!bond_mode_uses_arp(bond_mode)) {
4394 		if (!miimon) {
4395 			pr_warn("Warning: miimon must be specified, otherwise bonding will not detect link failure, speed and duplex which are essential for 802.3ad operation\n");
4396 			pr_warn("Forcing miimon to 100msec\n");
4397 			miimon = BOND_DEFAULT_MIIMON;
4398 		}
4399 	}
4400 
4401 	if (tx_queues < 1 || tx_queues > 255) {
4402 		pr_warn("Warning: tx_queues (%d) should be between 1 and 255, resetting to %d\n",
4403 			tx_queues, BOND_DEFAULT_TX_QUEUES);
4404 		tx_queues = BOND_DEFAULT_TX_QUEUES;
4405 	}
4406 
4407 	if ((all_slaves_active != 0) && (all_slaves_active != 1)) {
4408 		pr_warn("Warning: all_slaves_active module parameter (%d), not of valid value (0/1), so it was set to 0\n",
4409 			all_slaves_active);
4410 		all_slaves_active = 0;
4411 	}
4412 
4413 	if (resend_igmp < 0 || resend_igmp > 255) {
4414 		pr_warn("Warning: resend_igmp (%d) should be between 0 and 255, resetting to %d\n",
4415 			resend_igmp, BOND_DEFAULT_RESEND_IGMP);
4416 		resend_igmp = BOND_DEFAULT_RESEND_IGMP;
4417 	}
4418 
4419 	bond_opt_initval(&newval, packets_per_slave);
4420 	if (!bond_opt_parse(bond_opt_get(BOND_OPT_PACKETS_PER_SLAVE), &newval)) {
4421 		pr_warn("Warning: packets_per_slave (%d) should be between 0 and %u resetting to 1\n",
4422 			packets_per_slave, USHRT_MAX);
4423 		packets_per_slave = 1;
4424 	}
4425 
4426 	if (bond_mode == BOND_MODE_ALB) {
4427 		pr_notice("In ALB mode you might experience client disconnections upon reconnection of a link if the bonding module updelay parameter (%d msec) is incompatible with the forwarding delay time of the switch\n",
4428 			  updelay);
4429 	}
4430 
4431 	if (!miimon) {
4432 		if (updelay || downdelay) {
4433 			/* just warn the user the up/down delay will have
4434 			 * no effect since miimon is zero...
4435 			 */
4436 			pr_warn("Warning: miimon module parameter not set and updelay (%d) or downdelay (%d) module parameter is set; updelay and downdelay have no effect unless miimon is set\n",
4437 				updelay, downdelay);
4438 		}
4439 	} else {
4440 		/* don't allow arp monitoring */
4441 		if (arp_interval) {
4442 			pr_warn("Warning: miimon (%d) and arp_interval (%d) can't be used simultaneously, disabling ARP monitoring\n",
4443 				miimon, arp_interval);
4444 			arp_interval = 0;
4445 		}
4446 
4447 		if ((updelay % miimon) != 0) {
4448 			pr_warn("Warning: updelay (%d) is not a multiple of miimon (%d), updelay rounded to %d ms\n",
4449 				updelay, miimon, (updelay / miimon) * miimon);
4450 		}
4451 
4452 		updelay /= miimon;
4453 
4454 		if ((downdelay % miimon) != 0) {
4455 			pr_warn("Warning: downdelay (%d) is not a multiple of miimon (%d), downdelay rounded to %d ms\n",
4456 				downdelay, miimon,
4457 				(downdelay / miimon) * miimon);
4458 		}
4459 
4460 		downdelay /= miimon;
4461 	}
4462 
4463 	if (arp_interval < 0) {
4464 		pr_warn("Warning: arp_interval module parameter (%d), not in range 0-%d, so it was reset to 0\n",
4465 			arp_interval, INT_MAX);
4466 		arp_interval = 0;
4467 	}
4468 
4469 	for (arp_ip_count = 0, i = 0;
4470 	     (arp_ip_count < BOND_MAX_ARP_TARGETS) && arp_ip_target[i]; i++) {
4471 		__be32 ip;
4472 
4473 		/* not a complete check, but good enough to catch mistakes */
4474 		if (!in4_pton(arp_ip_target[i], -1, (u8 *)&ip, -1, NULL) ||
4475 		    !bond_is_ip_target_ok(ip)) {
4476 			pr_warn("Warning: bad arp_ip_target module parameter (%s), ARP monitoring will not be performed\n",
4477 				arp_ip_target[i]);
4478 			arp_interval = 0;
4479 		} else {
4480 			if (bond_get_targets_ip(arp_target, ip) == -1)
4481 				arp_target[arp_ip_count++] = ip;
4482 			else
4483 				pr_warn("Warning: duplicate address %pI4 in arp_ip_target, skipping\n",
4484 					&ip);
4485 		}
4486 	}
4487 
4488 	if (arp_interval && !arp_ip_count) {
4489 		/* don't allow arping if no arp_ip_target given... */
4490 		pr_warn("Warning: arp_interval module parameter (%d) specified without providing an arp_ip_target parameter, arp_interval was reset to 0\n",
4491 			arp_interval);
4492 		arp_interval = 0;
4493 	}
4494 
4495 	if (arp_validate) {
4496 		if (!arp_interval) {
4497 			pr_err("arp_validate requires arp_interval\n");
4498 			return -EINVAL;
4499 		}
4500 
4501 		bond_opt_initstr(&newval, arp_validate);
4502 		valptr = bond_opt_parse(bond_opt_get(BOND_OPT_ARP_VALIDATE),
4503 					&newval);
4504 		if (!valptr) {
4505 			pr_err("Error: invalid arp_validate \"%s\"\n",
4506 			       arp_validate);
4507 			return -EINVAL;
4508 		}
4509 		arp_validate_value = valptr->value;
4510 	} else {
4511 		arp_validate_value = 0;
4512 	}
4513 
4514 	if (arp_all_targets) {
4515 		bond_opt_initstr(&newval, arp_all_targets);
4516 		valptr = bond_opt_parse(bond_opt_get(BOND_OPT_ARP_ALL_TARGETS),
4517 					&newval);
4518 		if (!valptr) {
4519 			pr_err("Error: invalid arp_all_targets_value \"%s\"\n",
4520 			       arp_all_targets);
4521 			arp_all_targets_value = 0;
4522 		} else {
4523 			arp_all_targets_value = valptr->value;
4524 		}
4525 	}
4526 
4527 	if (miimon) {
4528 		pr_info("MII link monitoring set to %d ms\n", miimon);
4529 	} else if (arp_interval) {
4530 		valptr = bond_opt_get_val(BOND_OPT_ARP_VALIDATE,
4531 					  arp_validate_value);
4532 		pr_info("ARP monitoring set to %d ms, validate %s, with %d target(s):",
4533 			arp_interval, valptr->string, arp_ip_count);
4534 
4535 		for (i = 0; i < arp_ip_count; i++)
4536 			pr_cont(" %s", arp_ip_target[i]);
4537 
4538 		pr_cont("\n");
4539 
4540 	} else if (max_bonds) {
4541 		/* miimon and arp_interval not set, we need one so things
4542 		 * work as expected, see bonding.txt for details
4543 		 */
4544 		pr_debug("Warning: either miimon or arp_interval and arp_ip_target module parameters must be specified, otherwise bonding will not detect link failures! see bonding.txt for details\n");
4545 	}
4546 
4547 	if (primary && !bond_mode_uses_primary(bond_mode)) {
4548 		/* currently, using a primary only makes sense
4549 		 * in active backup, TLB or ALB modes
4550 		 */
4551 		pr_warn("Warning: %s primary device specified but has no effect in %s mode\n",
4552 			primary, bond_mode_name(bond_mode));
4553 		primary = NULL;
4554 	}
4555 
4556 	if (primary && primary_reselect) {
4557 		bond_opt_initstr(&newval, primary_reselect);
4558 		valptr = bond_opt_parse(bond_opt_get(BOND_OPT_PRIMARY_RESELECT),
4559 					&newval);
4560 		if (!valptr) {
4561 			pr_err("Error: Invalid primary_reselect \"%s\"\n",
4562 			       primary_reselect);
4563 			return -EINVAL;
4564 		}
4565 		primary_reselect_value = valptr->value;
4566 	} else {
4567 		primary_reselect_value = BOND_PRI_RESELECT_ALWAYS;
4568 	}
4569 
4570 	if (fail_over_mac) {
4571 		bond_opt_initstr(&newval, fail_over_mac);
4572 		valptr = bond_opt_parse(bond_opt_get(BOND_OPT_FAIL_OVER_MAC),
4573 					&newval);
4574 		if (!valptr) {
4575 			pr_err("Error: invalid fail_over_mac \"%s\"\n",
4576 			       fail_over_mac);
4577 			return -EINVAL;
4578 		}
4579 		fail_over_mac_value = valptr->value;
4580 		if (bond_mode != BOND_MODE_ACTIVEBACKUP)
4581 			pr_warn("Warning: fail_over_mac only affects active-backup mode\n");
4582 	} else {
4583 		fail_over_mac_value = BOND_FOM_NONE;
4584 	}
4585 
4586 	bond_opt_initstr(&newval, "default");
4587 	valptr = bond_opt_parse(
4588 			bond_opt_get(BOND_OPT_AD_ACTOR_SYS_PRIO),
4589 				     &newval);
4590 	if (!valptr) {
4591 		pr_err("Error: No ad_actor_sys_prio default value");
4592 		return -EINVAL;
4593 	}
4594 	ad_actor_sys_prio = valptr->value;
4595 
4596 	valptr = bond_opt_parse(bond_opt_get(BOND_OPT_AD_USER_PORT_KEY),
4597 				&newval);
4598 	if (!valptr) {
4599 		pr_err("Error: No ad_user_port_key default value");
4600 		return -EINVAL;
4601 	}
4602 	ad_user_port_key = valptr->value;
4603 
4604 	bond_opt_initstr(&newval, "default");
4605 	valptr = bond_opt_parse(bond_opt_get(BOND_OPT_TLB_DYNAMIC_LB), &newval);
4606 	if (!valptr) {
4607 		pr_err("Error: No tlb_dynamic_lb default value");
4608 		return -EINVAL;
4609 	}
4610 	tlb_dynamic_lb = valptr->value;
4611 
4612 	if (lp_interval == 0) {
4613 		pr_warn("Warning: ip_interval must be between 1 and %d, so it was reset to %d\n",
4614 			INT_MAX, BOND_ALB_DEFAULT_LP_INTERVAL);
4615 		lp_interval = BOND_ALB_DEFAULT_LP_INTERVAL;
4616 	}
4617 
4618 	/* fill params struct with the proper values */
4619 	params->mode = bond_mode;
4620 	params->xmit_policy = xmit_hashtype;
4621 	params->miimon = miimon;
4622 	params->num_peer_notif = num_peer_notif;
4623 	params->arp_interval = arp_interval;
4624 	params->arp_validate = arp_validate_value;
4625 	params->arp_all_targets = arp_all_targets_value;
4626 	params->updelay = updelay;
4627 	params->downdelay = downdelay;
4628 	params->use_carrier = use_carrier;
4629 	params->lacp_fast = lacp_fast;
4630 	params->primary[0] = 0;
4631 	params->primary_reselect = primary_reselect_value;
4632 	params->fail_over_mac = fail_over_mac_value;
4633 	params->tx_queues = tx_queues;
4634 	params->all_slaves_active = all_slaves_active;
4635 	params->resend_igmp = resend_igmp;
4636 	params->min_links = min_links;
4637 	params->lp_interval = lp_interval;
4638 	params->packets_per_slave = packets_per_slave;
4639 	params->tlb_dynamic_lb = tlb_dynamic_lb;
4640 	params->ad_actor_sys_prio = ad_actor_sys_prio;
4641 	eth_zero_addr(params->ad_actor_system);
4642 	params->ad_user_port_key = ad_user_port_key;
4643 	if (packets_per_slave > 0) {
4644 		params->reciprocal_packets_per_slave =
4645 			reciprocal_value(packets_per_slave);
4646 	} else {
4647 		/* reciprocal_packets_per_slave is unused if
4648 		 * packets_per_slave is 0 or 1, just initialize it
4649 		 */
4650 		params->reciprocal_packets_per_slave =
4651 			(struct reciprocal_value) { 0 };
4652 	}
4653 
4654 	if (primary) {
4655 		strncpy(params->primary, primary, IFNAMSIZ);
4656 		params->primary[IFNAMSIZ - 1] = 0;
4657 	}
4658 
4659 	memcpy(params->arp_targets, arp_target, sizeof(arp_target));
4660 
4661 	return 0;
4662 }
4663 
4664 /* Called from registration process */
4665 static int bond_init(struct net_device *bond_dev)
4666 {
4667 	struct bonding *bond = netdev_priv(bond_dev);
4668 	struct bond_net *bn = net_generic(dev_net(bond_dev), bond_net_id);
4669 
4670 	netdev_dbg(bond_dev, "Begin bond_init\n");
4671 
4672 	bond->wq = alloc_ordered_workqueue(bond_dev->name, WQ_MEM_RECLAIM);
4673 	if (!bond->wq)
4674 		return -ENOMEM;
4675 
4676 	netdev_lockdep_set_classes(bond_dev);
4677 
4678 	list_add_tail(&bond->bond_list, &bn->dev_list);
4679 
4680 	bond_prepare_sysfs_group(bond);
4681 
4682 	bond_debug_register(bond);
4683 
4684 	/* Ensure valid dev_addr */
4685 	if (is_zero_ether_addr(bond_dev->dev_addr) &&
4686 	    bond_dev->addr_assign_type == NET_ADDR_PERM)
4687 		eth_hw_addr_random(bond_dev);
4688 
4689 	return 0;
4690 }
4691 
4692 unsigned int bond_get_num_tx_queues(void)
4693 {
4694 	return tx_queues;
4695 }
4696 
4697 /* Create a new bond based on the specified name and bonding parameters.
4698  * If name is NULL, obtain a suitable "bond%d" name for us.
4699  * Caller must NOT hold rtnl_lock; we need to release it here before we
4700  * set up our sysfs entries.
4701  */
4702 int bond_create(struct net *net, const char *name)
4703 {
4704 	struct net_device *bond_dev;
4705 	struct bonding *bond;
4706 	struct alb_bond_info *bond_info;
4707 	int res;
4708 
4709 	rtnl_lock();
4710 
4711 	bond_dev = alloc_netdev_mq(sizeof(struct bonding),
4712 				   name ? name : "bond%d", NET_NAME_UNKNOWN,
4713 				   bond_setup, tx_queues);
4714 	if (!bond_dev) {
4715 		pr_err("%s: eek! can't alloc netdev!\n", name);
4716 		rtnl_unlock();
4717 		return -ENOMEM;
4718 	}
4719 
4720 	/*
4721 	 * Initialize rx_hashtbl_used_head to RLB_NULL_INDEX.
4722 	 * It is set to 0 by default which is wrong.
4723 	 */
4724 	bond = netdev_priv(bond_dev);
4725 	bond_info = &(BOND_ALB_INFO(bond));
4726 	bond_info->rx_hashtbl_used_head = RLB_NULL_INDEX;
4727 
4728 	dev_net_set(bond_dev, net);
4729 	bond_dev->rtnl_link_ops = &bond_link_ops;
4730 
4731 	res = register_netdevice(bond_dev);
4732 
4733 	netif_carrier_off(bond_dev);
4734 
4735 	bond_work_init_all(bond);
4736 
4737 	rtnl_unlock();
4738 	if (res < 0)
4739 		free_netdev(bond_dev);
4740 	return res;
4741 }
4742 
4743 static int __net_init bond_net_init(struct net *net)
4744 {
4745 	struct bond_net *bn = net_generic(net, bond_net_id);
4746 
4747 	bn->net = net;
4748 	INIT_LIST_HEAD(&bn->dev_list);
4749 
4750 	bond_create_proc_dir(bn);
4751 	bond_create_sysfs(bn);
4752 
4753 	return 0;
4754 }
4755 
4756 static void __net_exit bond_net_exit(struct net *net)
4757 {
4758 	struct bond_net *bn = net_generic(net, bond_net_id);
4759 	struct bonding *bond, *tmp_bond;
4760 	LIST_HEAD(list);
4761 
4762 	bond_destroy_sysfs(bn);
4763 
4764 	/* Kill off any bonds created after unregistering bond rtnl ops */
4765 	rtnl_lock();
4766 	list_for_each_entry_safe(bond, tmp_bond, &bn->dev_list, bond_list)
4767 		unregister_netdevice_queue(bond->dev, &list);
4768 	unregister_netdevice_many(&list);
4769 	rtnl_unlock();
4770 
4771 	bond_destroy_proc_dir(bn);
4772 }
4773 
4774 static struct pernet_operations bond_net_ops = {
4775 	.init = bond_net_init,
4776 	.exit = bond_net_exit,
4777 	.id   = &bond_net_id,
4778 	.size = sizeof(struct bond_net),
4779 };
4780 
4781 static int __init bonding_init(void)
4782 {
4783 	int i;
4784 	int res;
4785 
4786 	pr_info("%s", bond_version);
4787 
4788 	res = bond_check_params(&bonding_defaults);
4789 	if (res)
4790 		goto out;
4791 
4792 	res = register_pernet_subsys(&bond_net_ops);
4793 	if (res)
4794 		goto out;
4795 
4796 	res = bond_netlink_init();
4797 	if (res)
4798 		goto err_link;
4799 
4800 	bond_create_debugfs();
4801 
4802 	for (i = 0; i < max_bonds; i++) {
4803 		res = bond_create(&init_net, NULL);
4804 		if (res)
4805 			goto err;
4806 	}
4807 
4808 	register_netdevice_notifier(&bond_netdev_notifier);
4809 out:
4810 	return res;
4811 err:
4812 	bond_destroy_debugfs();
4813 	bond_netlink_fini();
4814 err_link:
4815 	unregister_pernet_subsys(&bond_net_ops);
4816 	goto out;
4817 
4818 }
4819 
4820 static void __exit bonding_exit(void)
4821 {
4822 	unregister_netdevice_notifier(&bond_netdev_notifier);
4823 
4824 	bond_destroy_debugfs();
4825 
4826 	bond_netlink_fini();
4827 	unregister_pernet_subsys(&bond_net_ops);
4828 
4829 #ifdef CONFIG_NET_POLL_CONTROLLER
4830 	/* Make sure we don't have an imbalance on our netpoll blocking */
4831 	WARN_ON(atomic_read(&netpoll_block_tx));
4832 #endif
4833 }
4834 
4835 module_init(bonding_init);
4836 module_exit(bonding_exit);
4837 MODULE_LICENSE("GPL");
4838 MODULE_VERSION(DRV_VERSION);
4839 MODULE_DESCRIPTION(DRV_DESCRIPTION ", v" DRV_VERSION);
4840 MODULE_AUTHOR("Thomas Davis, tadavis@lbl.gov and many others");
4841