xref: /linux/drivers/net/bonding/bond_main.c (revision cd354f1ae75e6466a7e31b727faede57a1f89ca5)
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 //#define BONDING_DEBUG 1
35 
36 #include <linux/kernel.h>
37 #include <linux/module.h>
38 #include <linux/types.h>
39 #include <linux/fcntl.h>
40 #include <linux/interrupt.h>
41 #include <linux/ptrace.h>
42 #include <linux/ioport.h>
43 #include <linux/in.h>
44 #include <net/ip.h>
45 #include <linux/ip.h>
46 #include <linux/tcp.h>
47 #include <linux/udp.h>
48 #include <linux/slab.h>
49 #include <linux/string.h>
50 #include <linux/init.h>
51 #include <linux/timer.h>
52 #include <linux/socket.h>
53 #include <linux/ctype.h>
54 #include <linux/inet.h>
55 #include <linux/bitops.h>
56 #include <asm/system.h>
57 #include <asm/io.h>
58 #include <asm/dma.h>
59 #include <asm/uaccess.h>
60 #include <linux/errno.h>
61 #include <linux/netdevice.h>
62 #include <linux/inetdevice.h>
63 #include <linux/etherdevice.h>
64 #include <linux/skbuff.h>
65 #include <net/sock.h>
66 #include <linux/rtnetlink.h>
67 #include <linux/proc_fs.h>
68 #include <linux/seq_file.h>
69 #include <linux/smp.h>
70 #include <linux/if_ether.h>
71 #include <net/arp.h>
72 #include <linux/mii.h>
73 #include <linux/ethtool.h>
74 #include <linux/if_vlan.h>
75 #include <linux/if_bonding.h>
76 #include <net/route.h>
77 #include "bonding.h"
78 #include "bond_3ad.h"
79 #include "bond_alb.h"
80 
81 /*---------------------------- Module parameters ----------------------------*/
82 
83 /* monitor all links that often (in milliseconds). <=0 disables monitoring */
84 #define BOND_LINK_MON_INTERV	0
85 #define BOND_LINK_ARP_INTERV	0
86 
87 static int max_bonds	= BOND_DEFAULT_MAX_BONDS;
88 static int miimon	= BOND_LINK_MON_INTERV;
89 static int updelay	= 0;
90 static int downdelay	= 0;
91 static int use_carrier	= 1;
92 static char *mode	= NULL;
93 static char *primary	= NULL;
94 static char *lacp_rate	= NULL;
95 static char *xmit_hash_policy = NULL;
96 static int arp_interval = BOND_LINK_ARP_INTERV;
97 static char *arp_ip_target[BOND_MAX_ARP_TARGETS] = { NULL, };
98 static char *arp_validate = NULL;
99 struct bond_params bonding_defaults;
100 
101 module_param(max_bonds, int, 0);
102 MODULE_PARM_DESC(max_bonds, "Max number of bonded devices");
103 module_param(miimon, int, 0);
104 MODULE_PARM_DESC(miimon, "Link check interval in milliseconds");
105 module_param(updelay, int, 0);
106 MODULE_PARM_DESC(updelay, "Delay before considering link up, in milliseconds");
107 module_param(downdelay, int, 0);
108 MODULE_PARM_DESC(downdelay, "Delay before considering link down, "
109 			    "in milliseconds");
110 module_param(use_carrier, int, 0);
111 MODULE_PARM_DESC(use_carrier, "Use netif_carrier_ok (vs MII ioctls) in miimon; "
112 			      "0 for off, 1 for on (default)");
113 module_param(mode, charp, 0);
114 MODULE_PARM_DESC(mode, "Mode of operation : 0 for balance-rr, "
115 		       "1 for active-backup, 2 for balance-xor, "
116 		       "3 for broadcast, 4 for 802.3ad, 5 for balance-tlb, "
117 		       "6 for balance-alb");
118 module_param(primary, charp, 0);
119 MODULE_PARM_DESC(primary, "Primary network device to use");
120 module_param(lacp_rate, charp, 0);
121 MODULE_PARM_DESC(lacp_rate, "LACPDU tx rate to request from 802.3ad partner "
122 			    "(slow/fast)");
123 module_param(xmit_hash_policy, charp, 0);
124 MODULE_PARM_DESC(xmit_hash_policy, "XOR hashing method: 0 for layer 2 (default)"
125 				   ", 1 for layer 3+4");
126 module_param(arp_interval, int, 0);
127 MODULE_PARM_DESC(arp_interval, "arp interval in milliseconds");
128 module_param_array(arp_ip_target, charp, NULL, 0);
129 MODULE_PARM_DESC(arp_ip_target, "arp targets in n.n.n.n form");
130 module_param(arp_validate, charp, 0);
131 MODULE_PARM_DESC(arp_validate, "validate src/dst of ARP probes: none (default), active, backup or all");
132 
133 /*----------------------------- Global variables ----------------------------*/
134 
135 static const char * const version =
136 	DRV_DESCRIPTION ": v" DRV_VERSION " (" DRV_RELDATE ")\n";
137 
138 LIST_HEAD(bond_dev_list);
139 
140 #ifdef CONFIG_PROC_FS
141 static struct proc_dir_entry *bond_proc_dir = NULL;
142 #endif
143 
144 extern struct rw_semaphore bonding_rwsem;
145 static u32 arp_target[BOND_MAX_ARP_TARGETS] = { 0, } ;
146 static int arp_ip_count	= 0;
147 static int bond_mode	= BOND_MODE_ROUNDROBIN;
148 static int xmit_hashtype= BOND_XMIT_POLICY_LAYER2;
149 static int lacp_fast	= 0;
150 
151 
152 struct bond_parm_tbl bond_lacp_tbl[] = {
153 {	"slow",		AD_LACP_SLOW},
154 {	"fast",		AD_LACP_FAST},
155 {	NULL,		-1},
156 };
157 
158 struct bond_parm_tbl bond_mode_tbl[] = {
159 {	"balance-rr",		BOND_MODE_ROUNDROBIN},
160 {	"active-backup",	BOND_MODE_ACTIVEBACKUP},
161 {	"balance-xor",		BOND_MODE_XOR},
162 {	"broadcast",		BOND_MODE_BROADCAST},
163 {	"802.3ad",		BOND_MODE_8023AD},
164 {	"balance-tlb",		BOND_MODE_TLB},
165 {	"balance-alb",		BOND_MODE_ALB},
166 {	NULL,			-1},
167 };
168 
169 struct bond_parm_tbl xmit_hashtype_tbl[] = {
170 {	"layer2",		BOND_XMIT_POLICY_LAYER2},
171 {	"layer3+4",		BOND_XMIT_POLICY_LAYER34},
172 {	NULL,			-1},
173 };
174 
175 struct bond_parm_tbl arp_validate_tbl[] = {
176 {	"none",			BOND_ARP_VALIDATE_NONE},
177 {	"active",		BOND_ARP_VALIDATE_ACTIVE},
178 {	"backup",		BOND_ARP_VALIDATE_BACKUP},
179 {	"all",			BOND_ARP_VALIDATE_ALL},
180 {	NULL,			-1},
181 };
182 
183 /*-------------------------- Forward declarations ---------------------------*/
184 
185 static void bond_send_gratuitous_arp(struct bonding *bond);
186 
187 /*---------------------------- General routines -----------------------------*/
188 
189 const char *bond_mode_name(int mode)
190 {
191 	switch (mode) {
192 	case BOND_MODE_ROUNDROBIN :
193 		return "load balancing (round-robin)";
194 	case BOND_MODE_ACTIVEBACKUP :
195 		return "fault-tolerance (active-backup)";
196 	case BOND_MODE_XOR :
197 		return "load balancing (xor)";
198 	case BOND_MODE_BROADCAST :
199 		return "fault-tolerance (broadcast)";
200 	case BOND_MODE_8023AD:
201 		return "IEEE 802.3ad Dynamic link aggregation";
202 	case BOND_MODE_TLB:
203 		return "transmit load balancing";
204 	case BOND_MODE_ALB:
205 		return "adaptive load balancing";
206 	default:
207 		return "unknown";
208 	}
209 }
210 
211 /*---------------------------------- VLAN -----------------------------------*/
212 
213 /**
214  * bond_add_vlan - add a new vlan id on bond
215  * @bond: bond that got the notification
216  * @vlan_id: the vlan id to add
217  *
218  * Returns -ENOMEM if allocation failed.
219  */
220 static int bond_add_vlan(struct bonding *bond, unsigned short vlan_id)
221 {
222 	struct vlan_entry *vlan;
223 
224 	dprintk("bond: %s, vlan id %d\n",
225 		(bond ? bond->dev->name: "None"), vlan_id);
226 
227 	vlan = kmalloc(sizeof(struct vlan_entry), GFP_KERNEL);
228 	if (!vlan) {
229 		return -ENOMEM;
230 	}
231 
232 	INIT_LIST_HEAD(&vlan->vlan_list);
233 	vlan->vlan_id = vlan_id;
234 	vlan->vlan_ip = 0;
235 
236 	write_lock_bh(&bond->lock);
237 
238 	list_add_tail(&vlan->vlan_list, &bond->vlan_list);
239 
240 	write_unlock_bh(&bond->lock);
241 
242 	dprintk("added VLAN ID %d on bond %s\n", vlan_id, bond->dev->name);
243 
244 	return 0;
245 }
246 
247 /**
248  * bond_del_vlan - delete a vlan id from bond
249  * @bond: bond that got the notification
250  * @vlan_id: the vlan id to delete
251  *
252  * returns -ENODEV if @vlan_id was not found in @bond.
253  */
254 static int bond_del_vlan(struct bonding *bond, unsigned short vlan_id)
255 {
256 	struct vlan_entry *vlan, *next;
257 	int res = -ENODEV;
258 
259 	dprintk("bond: %s, vlan id %d\n", bond->dev->name, vlan_id);
260 
261 	write_lock_bh(&bond->lock);
262 
263 	list_for_each_entry_safe(vlan, next, &bond->vlan_list, vlan_list) {
264 		if (vlan->vlan_id == vlan_id) {
265 			list_del(&vlan->vlan_list);
266 
267 			if ((bond->params.mode == BOND_MODE_TLB) ||
268 			    (bond->params.mode == BOND_MODE_ALB)) {
269 				bond_alb_clear_vlan(bond, vlan_id);
270 			}
271 
272 			dprintk("removed VLAN ID %d from bond %s\n", vlan_id,
273 				bond->dev->name);
274 
275 			kfree(vlan);
276 
277 			if (list_empty(&bond->vlan_list) &&
278 			    (bond->slave_cnt == 0)) {
279 				/* Last VLAN removed and no slaves, so
280 				 * restore block on adding VLANs. This will
281 				 * be removed once new slaves that are not
282 				 * VLAN challenged will be added.
283 				 */
284 				bond->dev->features |= NETIF_F_VLAN_CHALLENGED;
285 			}
286 
287 			res = 0;
288 			goto out;
289 		}
290 	}
291 
292 	dprintk("couldn't find VLAN ID %d in bond %s\n", vlan_id,
293 		bond->dev->name);
294 
295 out:
296 	write_unlock_bh(&bond->lock);
297 	return res;
298 }
299 
300 /**
301  * bond_has_challenged_slaves
302  * @bond: the bond we're working on
303  *
304  * Searches the slave list. Returns 1 if a vlan challenged slave
305  * was found, 0 otherwise.
306  *
307  * Assumes bond->lock is held.
308  */
309 static int bond_has_challenged_slaves(struct bonding *bond)
310 {
311 	struct slave *slave;
312 	int i;
313 
314 	bond_for_each_slave(bond, slave, i) {
315 		if (slave->dev->features & NETIF_F_VLAN_CHALLENGED) {
316 			dprintk("found VLAN challenged slave - %s\n",
317 				slave->dev->name);
318 			return 1;
319 		}
320 	}
321 
322 	dprintk("no VLAN challenged slaves found\n");
323 	return 0;
324 }
325 
326 /**
327  * bond_next_vlan - safely skip to the next item in the vlans list.
328  * @bond: the bond we're working on
329  * @curr: item we're advancing from
330  *
331  * Returns %NULL if list is empty, bond->next_vlan if @curr is %NULL,
332  * or @curr->next otherwise (even if it is @curr itself again).
333  *
334  * Caller must hold bond->lock
335  */
336 struct vlan_entry *bond_next_vlan(struct bonding *bond, struct vlan_entry *curr)
337 {
338 	struct vlan_entry *next, *last;
339 
340 	if (list_empty(&bond->vlan_list)) {
341 		return NULL;
342 	}
343 
344 	if (!curr) {
345 		next = list_entry(bond->vlan_list.next,
346 				  struct vlan_entry, vlan_list);
347 	} else {
348 		last = list_entry(bond->vlan_list.prev,
349 				  struct vlan_entry, vlan_list);
350 		if (last == curr) {
351 			next = list_entry(bond->vlan_list.next,
352 					  struct vlan_entry, vlan_list);
353 		} else {
354 			next = list_entry(curr->vlan_list.next,
355 					  struct vlan_entry, vlan_list);
356 		}
357 	}
358 
359 	return next;
360 }
361 
362 /**
363  * bond_dev_queue_xmit - Prepare skb for xmit.
364  *
365  * @bond: bond device that got this skb for tx.
366  * @skb: hw accel VLAN tagged skb to transmit
367  * @slave_dev: slave that is supposed to xmit this skbuff
368  *
369  * When the bond gets an skb to transmit that is
370  * already hardware accelerated VLAN tagged, and it
371  * needs to relay this skb to a slave that is not
372  * hw accel capable, the skb needs to be "unaccelerated",
373  * i.e. strip the hwaccel tag and re-insert it as part
374  * of the payload.
375  */
376 int bond_dev_queue_xmit(struct bonding *bond, struct sk_buff *skb, struct net_device *slave_dev)
377 {
378 	unsigned short vlan_id;
379 
380 	if (!list_empty(&bond->vlan_list) &&
381 	    !(slave_dev->features & NETIF_F_HW_VLAN_TX) &&
382 	    vlan_get_tag(skb, &vlan_id) == 0) {
383 		skb->dev = slave_dev;
384 		skb = vlan_put_tag(skb, vlan_id);
385 		if (!skb) {
386 			/* vlan_put_tag() frees the skb in case of error,
387 			 * so return success here so the calling functions
388 			 * won't attempt to free is again.
389 			 */
390 			return 0;
391 		}
392 	} else {
393 		skb->dev = slave_dev;
394 	}
395 
396 	skb->priority = 1;
397 	dev_queue_xmit(skb);
398 
399 	return 0;
400 }
401 
402 /*
403  * In the following 3 functions, bond_vlan_rx_register(), bond_vlan_rx_add_vid
404  * and bond_vlan_rx_kill_vid, We don't protect the slave list iteration with a
405  * lock because:
406  * a. This operation is performed in IOCTL context,
407  * b. The operation is protected by the RTNL semaphore in the 8021q code,
408  * c. Holding a lock with BH disabled while directly calling a base driver
409  *    entry point is generally a BAD idea.
410  *
411  * The design of synchronization/protection for this operation in the 8021q
412  * module is good for one or more VLAN devices over a single physical device
413  * and cannot be extended for a teaming solution like bonding, so there is a
414  * potential race condition here where a net device from the vlan group might
415  * be referenced (either by a base driver or the 8021q code) while it is being
416  * removed from the system. However, it turns out we're not making matters
417  * worse, and if it works for regular VLAN usage it will work here too.
418 */
419 
420 /**
421  * bond_vlan_rx_register - Propagates registration to slaves
422  * @bond_dev: bonding net device that got called
423  * @grp: vlan group being registered
424  */
425 static void bond_vlan_rx_register(struct net_device *bond_dev, struct vlan_group *grp)
426 {
427 	struct bonding *bond = bond_dev->priv;
428 	struct slave *slave;
429 	int i;
430 
431 	bond->vlgrp = grp;
432 
433 	bond_for_each_slave(bond, slave, i) {
434 		struct net_device *slave_dev = slave->dev;
435 
436 		if ((slave_dev->features & NETIF_F_HW_VLAN_RX) &&
437 		    slave_dev->vlan_rx_register) {
438 			slave_dev->vlan_rx_register(slave_dev, grp);
439 		}
440 	}
441 }
442 
443 /**
444  * bond_vlan_rx_add_vid - Propagates adding an id to slaves
445  * @bond_dev: bonding net device that got called
446  * @vid: vlan id being added
447  */
448 static void bond_vlan_rx_add_vid(struct net_device *bond_dev, uint16_t vid)
449 {
450 	struct bonding *bond = bond_dev->priv;
451 	struct slave *slave;
452 	int i, res;
453 
454 	bond_for_each_slave(bond, slave, i) {
455 		struct net_device *slave_dev = slave->dev;
456 
457 		if ((slave_dev->features & NETIF_F_HW_VLAN_FILTER) &&
458 		    slave_dev->vlan_rx_add_vid) {
459 			slave_dev->vlan_rx_add_vid(slave_dev, vid);
460 		}
461 	}
462 
463 	res = bond_add_vlan(bond, vid);
464 	if (res) {
465 		printk(KERN_ERR DRV_NAME
466 		       ": %s: Error: Failed to add vlan id %d\n",
467 		       bond_dev->name, vid);
468 	}
469 }
470 
471 /**
472  * bond_vlan_rx_kill_vid - Propagates deleting an id to slaves
473  * @bond_dev: bonding net device that got called
474  * @vid: vlan id being removed
475  */
476 static void bond_vlan_rx_kill_vid(struct net_device *bond_dev, uint16_t vid)
477 {
478 	struct bonding *bond = bond_dev->priv;
479 	struct slave *slave;
480 	struct net_device *vlan_dev;
481 	int i, res;
482 
483 	bond_for_each_slave(bond, slave, i) {
484 		struct net_device *slave_dev = slave->dev;
485 
486 		if ((slave_dev->features & NETIF_F_HW_VLAN_FILTER) &&
487 		    slave_dev->vlan_rx_kill_vid) {
488 			/* Save and then restore vlan_dev in the grp array,
489 			 * since the slave's driver might clear it.
490 			 */
491 			vlan_dev = bond->vlgrp->vlan_devices[vid];
492 			slave_dev->vlan_rx_kill_vid(slave_dev, vid);
493 			bond->vlgrp->vlan_devices[vid] = vlan_dev;
494 		}
495 	}
496 
497 	res = bond_del_vlan(bond, vid);
498 	if (res) {
499 		printk(KERN_ERR DRV_NAME
500 		       ": %s: Error: Failed to remove vlan id %d\n",
501 		       bond_dev->name, vid);
502 	}
503 }
504 
505 static void bond_add_vlans_on_slave(struct bonding *bond, struct net_device *slave_dev)
506 {
507 	struct vlan_entry *vlan;
508 
509 	write_lock_bh(&bond->lock);
510 
511 	if (list_empty(&bond->vlan_list)) {
512 		goto out;
513 	}
514 
515 	if ((slave_dev->features & NETIF_F_HW_VLAN_RX) &&
516 	    slave_dev->vlan_rx_register) {
517 		slave_dev->vlan_rx_register(slave_dev, bond->vlgrp);
518 	}
519 
520 	if (!(slave_dev->features & NETIF_F_HW_VLAN_FILTER) ||
521 	    !(slave_dev->vlan_rx_add_vid)) {
522 		goto out;
523 	}
524 
525 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
526 		slave_dev->vlan_rx_add_vid(slave_dev, vlan->vlan_id);
527 	}
528 
529 out:
530 	write_unlock_bh(&bond->lock);
531 }
532 
533 static void bond_del_vlans_from_slave(struct bonding *bond, struct net_device *slave_dev)
534 {
535 	struct vlan_entry *vlan;
536 	struct net_device *vlan_dev;
537 
538 	write_lock_bh(&bond->lock);
539 
540 	if (list_empty(&bond->vlan_list)) {
541 		goto out;
542 	}
543 
544 	if (!(slave_dev->features & NETIF_F_HW_VLAN_FILTER) ||
545 	    !(slave_dev->vlan_rx_kill_vid)) {
546 		goto unreg;
547 	}
548 
549 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
550 		/* Save and then restore vlan_dev in the grp array,
551 		 * since the slave's driver might clear it.
552 		 */
553 		vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
554 		slave_dev->vlan_rx_kill_vid(slave_dev, vlan->vlan_id);
555 		bond->vlgrp->vlan_devices[vlan->vlan_id] = vlan_dev;
556 	}
557 
558 unreg:
559 	if ((slave_dev->features & NETIF_F_HW_VLAN_RX) &&
560 	    slave_dev->vlan_rx_register) {
561 		slave_dev->vlan_rx_register(slave_dev, NULL);
562 	}
563 
564 out:
565 	write_unlock_bh(&bond->lock);
566 }
567 
568 /*------------------------------- Link status -------------------------------*/
569 
570 /*
571  * Set the carrier state for the master according to the state of its
572  * slaves.  If any slaves are up, the master is up.  In 802.3ad mode,
573  * do special 802.3ad magic.
574  *
575  * Returns zero if carrier state does not change, nonzero if it does.
576  */
577 static int bond_set_carrier(struct bonding *bond)
578 {
579 	struct slave *slave;
580 	int i;
581 
582 	if (bond->slave_cnt == 0)
583 		goto down;
584 
585 	if (bond->params.mode == BOND_MODE_8023AD)
586 		return bond_3ad_set_carrier(bond);
587 
588 	bond_for_each_slave(bond, slave, i) {
589 		if (slave->link == BOND_LINK_UP) {
590 			if (!netif_carrier_ok(bond->dev)) {
591 				netif_carrier_on(bond->dev);
592 				return 1;
593 			}
594 			return 0;
595 		}
596 	}
597 
598 down:
599 	if (netif_carrier_ok(bond->dev)) {
600 		netif_carrier_off(bond->dev);
601 		return 1;
602 	}
603 	return 0;
604 }
605 
606 /*
607  * Get link speed and duplex from the slave's base driver
608  * using ethtool. If for some reason the call fails or the
609  * values are invalid, fake speed and duplex to 100/Full
610  * and return error.
611  */
612 static int bond_update_speed_duplex(struct slave *slave)
613 {
614 	struct net_device *slave_dev = slave->dev;
615 	static int (* ioctl)(struct net_device *, struct ifreq *, int);
616 	struct ifreq ifr;
617 	struct ethtool_cmd etool;
618 
619 	/* Fake speed and duplex */
620 	slave->speed = SPEED_100;
621 	slave->duplex = DUPLEX_FULL;
622 
623 	if (slave_dev->ethtool_ops) {
624 		int res;
625 
626 		if (!slave_dev->ethtool_ops->get_settings) {
627 			return -1;
628 		}
629 
630 		res = slave_dev->ethtool_ops->get_settings(slave_dev, &etool);
631 		if (res < 0) {
632 			return -1;
633 		}
634 
635 		goto verify;
636 	}
637 
638 	ioctl = slave_dev->do_ioctl;
639 	strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
640 	etool.cmd = ETHTOOL_GSET;
641 	ifr.ifr_data = (char*)&etool;
642 	if (!ioctl || (IOCTL(slave_dev, &ifr, SIOCETHTOOL) < 0)) {
643 		return -1;
644 	}
645 
646 verify:
647 	switch (etool.speed) {
648 	case SPEED_10:
649 	case SPEED_100:
650 	case SPEED_1000:
651 	case SPEED_10000:
652 		break;
653 	default:
654 		return -1;
655 	}
656 
657 	switch (etool.duplex) {
658 	case DUPLEX_FULL:
659 	case DUPLEX_HALF:
660 		break;
661 	default:
662 		return -1;
663 	}
664 
665 	slave->speed = etool.speed;
666 	slave->duplex = etool.duplex;
667 
668 	return 0;
669 }
670 
671 /*
672  * if <dev> supports MII link status reporting, check its link status.
673  *
674  * We either do MII/ETHTOOL ioctls, or check netif_carrier_ok(),
675  * depening upon the setting of the use_carrier parameter.
676  *
677  * Return either BMSR_LSTATUS, meaning that the link is up (or we
678  * can't tell and just pretend it is), or 0, meaning that the link is
679  * down.
680  *
681  * If reporting is non-zero, instead of faking link up, return -1 if
682  * both ETHTOOL and MII ioctls fail (meaning the device does not
683  * support them).  If use_carrier is set, return whatever it says.
684  * It'd be nice if there was a good way to tell if a driver supports
685  * netif_carrier, but there really isn't.
686  */
687 static int bond_check_dev_link(struct bonding *bond, struct net_device *slave_dev, int reporting)
688 {
689 	static int (* ioctl)(struct net_device *, struct ifreq *, int);
690 	struct ifreq ifr;
691 	struct mii_ioctl_data *mii;
692 	struct ethtool_value etool;
693 
694 	if (bond->params.use_carrier) {
695 		return netif_carrier_ok(slave_dev) ? BMSR_LSTATUS : 0;
696 	}
697 
698 	ioctl = slave_dev->do_ioctl;
699 	if (ioctl) {
700 		/* TODO: set pointer to correct ioctl on a per team member */
701 		/*       bases to make this more efficient. that is, once  */
702 		/*       we determine the correct ioctl, we will always    */
703 		/*       call it and not the others for that team          */
704 		/*       member.                                           */
705 
706 		/*
707 		 * We cannot assume that SIOCGMIIPHY will also read a
708 		 * register; not all network drivers (e.g., e100)
709 		 * support that.
710 		 */
711 
712 		/* Yes, the mii is overlaid on the ifreq.ifr_ifru */
713 		strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
714 		mii = if_mii(&ifr);
715 		if (IOCTL(slave_dev, &ifr, SIOCGMIIPHY) == 0) {
716 			mii->reg_num = MII_BMSR;
717 			if (IOCTL(slave_dev, &ifr, SIOCGMIIREG) == 0) {
718 				return (mii->val_out & BMSR_LSTATUS);
719 			}
720 		}
721 	}
722 
723 	/* try SIOCETHTOOL ioctl, some drivers cache ETHTOOL_GLINK */
724 	/* for a period of time so we attempt to get link status   */
725 	/* from it last if the above MII ioctls fail...            */
726 	if (slave_dev->ethtool_ops) {
727 		if (slave_dev->ethtool_ops->get_link) {
728 			u32 link;
729 
730 			link = slave_dev->ethtool_ops->get_link(slave_dev);
731 
732 			return link ? BMSR_LSTATUS : 0;
733 		}
734 	}
735 
736 	if (ioctl) {
737 		strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
738 		etool.cmd = ETHTOOL_GLINK;
739 		ifr.ifr_data = (char*)&etool;
740 		if (IOCTL(slave_dev, &ifr, SIOCETHTOOL) == 0) {
741 			if (etool.data == 1) {
742 				return BMSR_LSTATUS;
743 			} else {
744 				dprintk("SIOCETHTOOL shows link down\n");
745 				return 0;
746 			}
747 		}
748 	}
749 
750 	/*
751 	 * If reporting, report that either there's no dev->do_ioctl,
752 	 * or both SIOCGMIIREG and SIOCETHTOOL failed (meaning that we
753 	 * cannot report link status).  If not reporting, pretend
754 	 * we're ok.
755 	 */
756 	return (reporting ? -1 : BMSR_LSTATUS);
757 }
758 
759 /*----------------------------- Multicast list ------------------------------*/
760 
761 /*
762  * Returns 0 if dmi1 and dmi2 are the same, non-0 otherwise
763  */
764 static inline int bond_is_dmi_same(struct dev_mc_list *dmi1, struct dev_mc_list *dmi2)
765 {
766 	return memcmp(dmi1->dmi_addr, dmi2->dmi_addr, dmi1->dmi_addrlen) == 0 &&
767 			dmi1->dmi_addrlen == dmi2->dmi_addrlen;
768 }
769 
770 /*
771  * returns dmi entry if found, NULL otherwise
772  */
773 static struct dev_mc_list *bond_mc_list_find_dmi(struct dev_mc_list *dmi, struct dev_mc_list *mc_list)
774 {
775 	struct dev_mc_list *idmi;
776 
777 	for (idmi = mc_list; idmi; idmi = idmi->next) {
778 		if (bond_is_dmi_same(dmi, idmi)) {
779 			return idmi;
780 		}
781 	}
782 
783 	return NULL;
784 }
785 
786 /*
787  * Push the promiscuity flag down to appropriate slaves
788  */
789 static void bond_set_promiscuity(struct bonding *bond, int inc)
790 {
791 	if (USES_PRIMARY(bond->params.mode)) {
792 		/* write lock already acquired */
793 		if (bond->curr_active_slave) {
794 			dev_set_promiscuity(bond->curr_active_slave->dev, inc);
795 		}
796 	} else {
797 		struct slave *slave;
798 		int i;
799 		bond_for_each_slave(bond, slave, i) {
800 			dev_set_promiscuity(slave->dev, inc);
801 		}
802 	}
803 }
804 
805 /*
806  * Push the allmulti flag down to all slaves
807  */
808 static void bond_set_allmulti(struct bonding *bond, int inc)
809 {
810 	if (USES_PRIMARY(bond->params.mode)) {
811 		/* write lock already acquired */
812 		if (bond->curr_active_slave) {
813 			dev_set_allmulti(bond->curr_active_slave->dev, inc);
814 		}
815 	} else {
816 		struct slave *slave;
817 		int i;
818 		bond_for_each_slave(bond, slave, i) {
819 			dev_set_allmulti(slave->dev, inc);
820 		}
821 	}
822 }
823 
824 /*
825  * Add a Multicast address to slaves
826  * according to mode
827  */
828 static void bond_mc_add(struct bonding *bond, void *addr, int alen)
829 {
830 	if (USES_PRIMARY(bond->params.mode)) {
831 		/* write lock already acquired */
832 		if (bond->curr_active_slave) {
833 			dev_mc_add(bond->curr_active_slave->dev, addr, alen, 0);
834 		}
835 	} else {
836 		struct slave *slave;
837 		int i;
838 		bond_for_each_slave(bond, slave, i) {
839 			dev_mc_add(slave->dev, addr, alen, 0);
840 		}
841 	}
842 }
843 
844 /*
845  * Remove a multicast address from slave
846  * according to mode
847  */
848 static void bond_mc_delete(struct bonding *bond, void *addr, int alen)
849 {
850 	if (USES_PRIMARY(bond->params.mode)) {
851 		/* write lock already acquired */
852 		if (bond->curr_active_slave) {
853 			dev_mc_delete(bond->curr_active_slave->dev, addr, alen, 0);
854 		}
855 	} else {
856 		struct slave *slave;
857 		int i;
858 		bond_for_each_slave(bond, slave, i) {
859 			dev_mc_delete(slave->dev, addr, alen, 0);
860 		}
861 	}
862 }
863 
864 /*
865  * Totally destroys the mc_list in bond
866  */
867 static void bond_mc_list_destroy(struct bonding *bond)
868 {
869 	struct dev_mc_list *dmi;
870 
871 	dmi = bond->mc_list;
872 	while (dmi) {
873 		bond->mc_list = dmi->next;
874 		kfree(dmi);
875 		dmi = bond->mc_list;
876 	}
877 }
878 
879 /*
880  * Copy all the Multicast addresses from src to the bonding device dst
881  */
882 static int bond_mc_list_copy(struct dev_mc_list *mc_list, struct bonding *bond,
883 			     gfp_t gfp_flag)
884 {
885 	struct dev_mc_list *dmi, *new_dmi;
886 
887 	for (dmi = mc_list; dmi; dmi = dmi->next) {
888 		new_dmi = kmalloc(sizeof(struct dev_mc_list), gfp_flag);
889 
890 		if (!new_dmi) {
891 			/* FIXME: Potential memory leak !!! */
892 			return -ENOMEM;
893 		}
894 
895 		new_dmi->next = bond->mc_list;
896 		bond->mc_list = new_dmi;
897 		new_dmi->dmi_addrlen = dmi->dmi_addrlen;
898 		memcpy(new_dmi->dmi_addr, dmi->dmi_addr, dmi->dmi_addrlen);
899 		new_dmi->dmi_users = dmi->dmi_users;
900 		new_dmi->dmi_gusers = dmi->dmi_gusers;
901 	}
902 
903 	return 0;
904 }
905 
906 /*
907  * flush all members of flush->mc_list from device dev->mc_list
908  */
909 static void bond_mc_list_flush(struct net_device *bond_dev, struct net_device *slave_dev)
910 {
911 	struct bonding *bond = bond_dev->priv;
912 	struct dev_mc_list *dmi;
913 
914 	for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
915 		dev_mc_delete(slave_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
916 	}
917 
918 	if (bond->params.mode == BOND_MODE_8023AD) {
919 		/* del lacpdu mc addr from mc list */
920 		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
921 
922 		dev_mc_delete(slave_dev, lacpdu_multicast, ETH_ALEN, 0);
923 	}
924 }
925 
926 /*--------------------------- Active slave change ---------------------------*/
927 
928 /*
929  * Update the mc list and multicast-related flags for the new and
930  * old active slaves (if any) according to the multicast mode, and
931  * promiscuous flags unconditionally.
932  */
933 static void bond_mc_swap(struct bonding *bond, struct slave *new_active, struct slave *old_active)
934 {
935 	struct dev_mc_list *dmi;
936 
937 	if (!USES_PRIMARY(bond->params.mode)) {
938 		/* nothing to do -  mc list is already up-to-date on
939 		 * all slaves
940 		 */
941 		return;
942 	}
943 
944 	if (old_active) {
945 		if (bond->dev->flags & IFF_PROMISC) {
946 			dev_set_promiscuity(old_active->dev, -1);
947 		}
948 
949 		if (bond->dev->flags & IFF_ALLMULTI) {
950 			dev_set_allmulti(old_active->dev, -1);
951 		}
952 
953 		for (dmi = bond->dev->mc_list; dmi; dmi = dmi->next) {
954 			dev_mc_delete(old_active->dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
955 		}
956 	}
957 
958 	if (new_active) {
959 		if (bond->dev->flags & IFF_PROMISC) {
960 			dev_set_promiscuity(new_active->dev, 1);
961 		}
962 
963 		if (bond->dev->flags & IFF_ALLMULTI) {
964 			dev_set_allmulti(new_active->dev, 1);
965 		}
966 
967 		for (dmi = bond->dev->mc_list; dmi; dmi = dmi->next) {
968 			dev_mc_add(new_active->dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
969 		}
970 	}
971 }
972 
973 /**
974  * find_best_interface - select the best available slave to be the active one
975  * @bond: our bonding struct
976  *
977  * Warning: Caller must hold curr_slave_lock for writing.
978  */
979 static struct slave *bond_find_best_slave(struct bonding *bond)
980 {
981 	struct slave *new_active, *old_active;
982 	struct slave *bestslave = NULL;
983 	int mintime = bond->params.updelay;
984 	int i;
985 
986 	new_active = old_active = bond->curr_active_slave;
987 
988 	if (!new_active) { /* there were no active slaves left */
989 		if (bond->slave_cnt > 0) {  /* found one slave */
990 			new_active = bond->first_slave;
991 		} else {
992 			return NULL; /* still no slave, return NULL */
993 		}
994 	}
995 
996 	/* first try the primary link; if arping, a link must tx/rx traffic
997 	 * before it can be considered the curr_active_slave - also, we would skip
998 	 * slaves between the curr_active_slave and primary_slave that may be up
999 	 * and able to arp
1000 	 */
1001 	if ((bond->primary_slave) &&
1002 	    (!bond->params.arp_interval) &&
1003 	    (IS_UP(bond->primary_slave->dev))) {
1004 		new_active = bond->primary_slave;
1005 	}
1006 
1007 	/* remember where to stop iterating over the slaves */
1008 	old_active = new_active;
1009 
1010 	bond_for_each_slave_from(bond, new_active, i, old_active) {
1011 		if (IS_UP(new_active->dev)) {
1012 			if (new_active->link == BOND_LINK_UP) {
1013 				return new_active;
1014 			} else if (new_active->link == BOND_LINK_BACK) {
1015 				/* link up, but waiting for stabilization */
1016 				if (new_active->delay < mintime) {
1017 					mintime = new_active->delay;
1018 					bestslave = new_active;
1019 				}
1020 			}
1021 		}
1022 	}
1023 
1024 	return bestslave;
1025 }
1026 
1027 /**
1028  * change_active_interface - change the active slave into the specified one
1029  * @bond: our bonding struct
1030  * @new: the new slave to make the active one
1031  *
1032  * Set the new slave to the bond's settings and unset them on the old
1033  * curr_active_slave.
1034  * Setting include flags, mc-list, promiscuity, allmulti, etc.
1035  *
1036  * If @new's link state is %BOND_LINK_BACK we'll set it to %BOND_LINK_UP,
1037  * because it is apparently the best available slave we have, even though its
1038  * updelay hasn't timed out yet.
1039  *
1040  * Warning: Caller must hold curr_slave_lock for writing.
1041  */
1042 void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
1043 {
1044 	struct slave *old_active = bond->curr_active_slave;
1045 
1046 	if (old_active == new_active) {
1047 		return;
1048 	}
1049 
1050 	if (new_active) {
1051 		if (new_active->link == BOND_LINK_BACK) {
1052 			if (USES_PRIMARY(bond->params.mode)) {
1053 				printk(KERN_INFO DRV_NAME
1054 				       ": %s: making interface %s the new "
1055 				       "active one %d ms earlier.\n",
1056 				       bond->dev->name, new_active->dev->name,
1057 				       (bond->params.updelay - new_active->delay) * bond->params.miimon);
1058 			}
1059 
1060 			new_active->delay = 0;
1061 			new_active->link = BOND_LINK_UP;
1062 			new_active->jiffies = jiffies;
1063 
1064 			if (bond->params.mode == BOND_MODE_8023AD) {
1065 				bond_3ad_handle_link_change(new_active, BOND_LINK_UP);
1066 			}
1067 
1068 			if ((bond->params.mode == BOND_MODE_TLB) ||
1069 			    (bond->params.mode == BOND_MODE_ALB)) {
1070 				bond_alb_handle_link_change(bond, new_active, BOND_LINK_UP);
1071 			}
1072 		} else {
1073 			if (USES_PRIMARY(bond->params.mode)) {
1074 				printk(KERN_INFO DRV_NAME
1075 				       ": %s: making interface %s the new "
1076 				       "active one.\n",
1077 				       bond->dev->name, new_active->dev->name);
1078 			}
1079 		}
1080 	}
1081 
1082 	if (USES_PRIMARY(bond->params.mode)) {
1083 		bond_mc_swap(bond, new_active, old_active);
1084 	}
1085 
1086 	if ((bond->params.mode == BOND_MODE_TLB) ||
1087 	    (bond->params.mode == BOND_MODE_ALB)) {
1088 		bond_alb_handle_active_change(bond, new_active);
1089 		if (old_active)
1090 			bond_set_slave_inactive_flags(old_active);
1091 		if (new_active)
1092 			bond_set_slave_active_flags(new_active);
1093 	} else {
1094 		bond->curr_active_slave = new_active;
1095 	}
1096 
1097 	if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
1098 		if (old_active) {
1099 			bond_set_slave_inactive_flags(old_active);
1100 		}
1101 
1102 		if (new_active) {
1103 			bond_set_slave_active_flags(new_active);
1104 		}
1105 		bond_send_gratuitous_arp(bond);
1106 	}
1107 }
1108 
1109 /**
1110  * bond_select_active_slave - select a new active slave, if needed
1111  * @bond: our bonding struct
1112  *
1113  * This functions shoud be called when one of the following occurs:
1114  * - The old curr_active_slave has been released or lost its link.
1115  * - The primary_slave has got its link back.
1116  * - A slave has got its link back and there's no old curr_active_slave.
1117  *
1118  * Warning: Caller must hold curr_slave_lock for writing.
1119  */
1120 void bond_select_active_slave(struct bonding *bond)
1121 {
1122 	struct slave *best_slave;
1123 	int rv;
1124 
1125 	best_slave = bond_find_best_slave(bond);
1126 	if (best_slave != bond->curr_active_slave) {
1127 		bond_change_active_slave(bond, best_slave);
1128 		rv = bond_set_carrier(bond);
1129 		if (!rv)
1130 			return;
1131 
1132 		if (netif_carrier_ok(bond->dev)) {
1133 			printk(KERN_INFO DRV_NAME
1134 			       ": %s: first active interface up!\n",
1135 			       bond->dev->name);
1136 		} else {
1137 			printk(KERN_INFO DRV_NAME ": %s: "
1138 			       "now running without any active interface !\n",
1139 			       bond->dev->name);
1140 		}
1141 	}
1142 }
1143 
1144 /*--------------------------- slave list handling ---------------------------*/
1145 
1146 /*
1147  * This function attaches the slave to the end of list.
1148  *
1149  * bond->lock held for writing by caller.
1150  */
1151 static void bond_attach_slave(struct bonding *bond, struct slave *new_slave)
1152 {
1153 	if (bond->first_slave == NULL) { /* attaching the first slave */
1154 		new_slave->next = new_slave;
1155 		new_slave->prev = new_slave;
1156 		bond->first_slave = new_slave;
1157 	} else {
1158 		new_slave->next = bond->first_slave;
1159 		new_slave->prev = bond->first_slave->prev;
1160 		new_slave->next->prev = new_slave;
1161 		new_slave->prev->next = new_slave;
1162 	}
1163 
1164 	bond->slave_cnt++;
1165 }
1166 
1167 /*
1168  * This function detaches the slave from the list.
1169  * WARNING: no check is made to verify if the slave effectively
1170  * belongs to <bond>.
1171  * Nothing is freed on return, structures are just unchained.
1172  * If any slave pointer in bond was pointing to <slave>,
1173  * it should be changed by the calling function.
1174  *
1175  * bond->lock held for writing by caller.
1176  */
1177 static void bond_detach_slave(struct bonding *bond, struct slave *slave)
1178 {
1179 	if (slave->next) {
1180 		slave->next->prev = slave->prev;
1181 	}
1182 
1183 	if (slave->prev) {
1184 		slave->prev->next = slave->next;
1185 	}
1186 
1187 	if (bond->first_slave == slave) { /* slave is the first slave */
1188 		if (bond->slave_cnt > 1) { /* there are more slave */
1189 			bond->first_slave = slave->next;
1190 		} else {
1191 			bond->first_slave = NULL; /* slave was the last one */
1192 		}
1193 	}
1194 
1195 	slave->next = NULL;
1196 	slave->prev = NULL;
1197 	bond->slave_cnt--;
1198 }
1199 
1200 /*---------------------------------- IOCTL ----------------------------------*/
1201 
1202 int bond_sethwaddr(struct net_device *bond_dev, struct net_device *slave_dev)
1203 {
1204 	dprintk("bond_dev=%p\n", bond_dev);
1205 	dprintk("slave_dev=%p\n", slave_dev);
1206 	dprintk("slave_dev->addr_len=%d\n", slave_dev->addr_len);
1207 	memcpy(bond_dev->dev_addr, slave_dev->dev_addr, slave_dev->addr_len);
1208 	return 0;
1209 }
1210 
1211 #define BOND_INTERSECT_FEATURES \
1212 	(NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_TSO | NETIF_F_UFO)
1213 
1214 /*
1215  * Compute the common dev->feature set available to all slaves.  Some
1216  * feature bits are managed elsewhere, so preserve feature bits set on
1217  * master device that are not part of the examined set.
1218  */
1219 static int bond_compute_features(struct bonding *bond)
1220 {
1221 	unsigned long features = BOND_INTERSECT_FEATURES;
1222 	struct slave *slave;
1223 	struct net_device *bond_dev = bond->dev;
1224 	unsigned short max_hard_header_len = ETH_HLEN;
1225 	int i;
1226 
1227 	bond_for_each_slave(bond, slave, i) {
1228 		features &= (slave->dev->features & BOND_INTERSECT_FEATURES);
1229 		if (slave->dev->hard_header_len > max_hard_header_len)
1230 			max_hard_header_len = slave->dev->hard_header_len;
1231 	}
1232 
1233 	if ((features & NETIF_F_SG) &&
1234 	    !(features & NETIF_F_ALL_CSUM))
1235 		features &= ~NETIF_F_SG;
1236 
1237 	/*
1238 	 * features will include NETIF_F_TSO (NETIF_F_UFO) iff all
1239 	 * slave devices support NETIF_F_TSO (NETIF_F_UFO), which
1240 	 * implies that all slaves also support scatter-gather
1241 	 * (NETIF_F_SG), which implies that features also includes
1242 	 * NETIF_F_SG. So no need to check whether we have an
1243 	 * illegal combination of NETIF_F_{TSO,UFO} and
1244 	 * !NETIF_F_SG
1245 	 */
1246 
1247 	features |= (bond_dev->features & ~BOND_INTERSECT_FEATURES);
1248 	bond_dev->features = features;
1249 	bond_dev->hard_header_len = max_hard_header_len;
1250 
1251 	return 0;
1252 }
1253 
1254 /* enslave device <slave> to bond device <master> */
1255 int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
1256 {
1257 	struct bonding *bond = bond_dev->priv;
1258 	struct slave *new_slave = NULL;
1259 	struct dev_mc_list *dmi;
1260 	struct sockaddr addr;
1261 	int link_reporting;
1262 	int old_features = bond_dev->features;
1263 	int res = 0;
1264 
1265 	if (!bond->params.use_carrier && slave_dev->ethtool_ops == NULL &&
1266 		slave_dev->do_ioctl == NULL) {
1267 		printk(KERN_WARNING DRV_NAME
1268 		       ": %s: Warning: no link monitoring support for %s\n",
1269 		       bond_dev->name, slave_dev->name);
1270 	}
1271 
1272 	/* bond must be initialized by bond_open() before enslaving */
1273 	if (!(bond_dev->flags & IFF_UP)) {
1274 		dprintk("Error, master_dev is not up\n");
1275 		return -EPERM;
1276 	}
1277 
1278 	/* already enslaved */
1279 	if (slave_dev->flags & IFF_SLAVE) {
1280 		dprintk("Error, Device was already enslaved\n");
1281 		return -EBUSY;
1282 	}
1283 
1284 	/* vlan challenged mutual exclusion */
1285 	/* no need to lock since we're protected by rtnl_lock */
1286 	if (slave_dev->features & NETIF_F_VLAN_CHALLENGED) {
1287 		dprintk("%s: NETIF_F_VLAN_CHALLENGED\n", slave_dev->name);
1288 		if (!list_empty(&bond->vlan_list)) {
1289 			printk(KERN_ERR DRV_NAME
1290 			       ": %s: Error: cannot enslave VLAN "
1291 			       "challenged slave %s on VLAN enabled "
1292 			       "bond %s\n", bond_dev->name, slave_dev->name,
1293 			       bond_dev->name);
1294 			return -EPERM;
1295 		} else {
1296 			printk(KERN_WARNING DRV_NAME
1297 			       ": %s: Warning: enslaved VLAN challenged "
1298 			       "slave %s. Adding VLANs will be blocked as "
1299 			       "long as %s is part of bond %s\n",
1300 			       bond_dev->name, slave_dev->name, slave_dev->name,
1301 			       bond_dev->name);
1302 			bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
1303 		}
1304 	} else {
1305 		dprintk("%s: ! NETIF_F_VLAN_CHALLENGED\n", slave_dev->name);
1306 		if (bond->slave_cnt == 0) {
1307 			/* First slave, and it is not VLAN challenged,
1308 			 * so remove the block of adding VLANs over the bond.
1309 			 */
1310 			bond_dev->features &= ~NETIF_F_VLAN_CHALLENGED;
1311 		}
1312 	}
1313 
1314 	/*
1315 	 * Old ifenslave binaries are no longer supported.  These can
1316 	 * be identified with moderate accurary by the state of the slave:
1317 	 * the current ifenslave will set the interface down prior to
1318 	 * enslaving it; the old ifenslave will not.
1319 	 */
1320 	if ((slave_dev->flags & IFF_UP)) {
1321 		printk(KERN_ERR DRV_NAME ": %s is up. "
1322 		       "This may be due to an out of date ifenslave.\n",
1323 		       slave_dev->name);
1324 		res = -EPERM;
1325 		goto err_undo_flags;
1326 	}
1327 
1328 	if (slave_dev->set_mac_address == NULL) {
1329 		printk(KERN_ERR DRV_NAME
1330 			": %s: Error: The slave device you specified does "
1331 			"not support setting the MAC address. "
1332 			"Your kernel likely does not support slave "
1333 			"devices.\n", bond_dev->name);
1334   		res = -EOPNOTSUPP;
1335 		goto err_undo_flags;
1336 	}
1337 
1338 	if (slave_dev->get_stats == NULL) {
1339 		printk(KERN_NOTICE DRV_NAME
1340 			": %s: the driver for slave device %s does not provide "
1341 			"get_stats function, network statistics will be "
1342 			"inaccurate.\n", bond_dev->name, slave_dev->name);
1343 	}
1344 
1345 	new_slave = kzalloc(sizeof(struct slave), GFP_KERNEL);
1346 	if (!new_slave) {
1347 		res = -ENOMEM;
1348 		goto err_undo_flags;
1349 	}
1350 
1351 	/* save slave's original flags before calling
1352 	 * netdev_set_master and dev_open
1353 	 */
1354 	new_slave->original_flags = slave_dev->flags;
1355 
1356 	/*
1357 	 * Save slave's original ("permanent") mac address for modes
1358 	 * that need it, and for restoring it upon release, and then
1359 	 * set it to the master's address
1360 	 */
1361 	memcpy(new_slave->perm_hwaddr, slave_dev->dev_addr, ETH_ALEN);
1362 
1363 	/*
1364 	 * Set slave to master's mac address.  The application already
1365 	 * set the master's mac address to that of the first slave
1366 	 */
1367 	memcpy(addr.sa_data, bond_dev->dev_addr, bond_dev->addr_len);
1368 	addr.sa_family = slave_dev->type;
1369 	res = dev_set_mac_address(slave_dev, &addr);
1370 	if (res) {
1371 		dprintk("Error %d calling set_mac_address\n", res);
1372 		goto err_free;
1373 	}
1374 
1375 	/* open the slave since the application closed it */
1376 	res = dev_open(slave_dev);
1377 	if (res) {
1378 		dprintk("Openning slave %s failed\n", slave_dev->name);
1379 		goto err_restore_mac;
1380 	}
1381 
1382 	res = netdev_set_master(slave_dev, bond_dev);
1383 	if (res) {
1384 		dprintk("Error %d calling netdev_set_master\n", res);
1385 		goto err_close;
1386 	}
1387 
1388 	new_slave->dev = slave_dev;
1389 	slave_dev->priv_flags |= IFF_BONDING;
1390 
1391 	if ((bond->params.mode == BOND_MODE_TLB) ||
1392 	    (bond->params.mode == BOND_MODE_ALB)) {
1393 		/* bond_alb_init_slave() must be called before all other stages since
1394 		 * it might fail and we do not want to have to undo everything
1395 		 */
1396 		res = bond_alb_init_slave(bond, new_slave);
1397 		if (res) {
1398 			goto err_unset_master;
1399 		}
1400 	}
1401 
1402 	/* If the mode USES_PRIMARY, then the new slave gets the
1403 	 * master's promisc (and mc) settings only if it becomes the
1404 	 * curr_active_slave, and that is taken care of later when calling
1405 	 * bond_change_active()
1406 	 */
1407 	if (!USES_PRIMARY(bond->params.mode)) {
1408 		/* set promiscuity level to new slave */
1409 		if (bond_dev->flags & IFF_PROMISC) {
1410 			dev_set_promiscuity(slave_dev, 1);
1411 		}
1412 
1413 		/* set allmulti level to new slave */
1414 		if (bond_dev->flags & IFF_ALLMULTI) {
1415 			dev_set_allmulti(slave_dev, 1);
1416 		}
1417 
1418 		/* upload master's mc_list to new slave */
1419 		for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
1420 			dev_mc_add (slave_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
1421 		}
1422 	}
1423 
1424 	if (bond->params.mode == BOND_MODE_8023AD) {
1425 		/* add lacpdu mc addr to mc list */
1426 		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
1427 
1428 		dev_mc_add(slave_dev, lacpdu_multicast, ETH_ALEN, 0);
1429 	}
1430 
1431 	bond_add_vlans_on_slave(bond, slave_dev);
1432 
1433 	write_lock_bh(&bond->lock);
1434 
1435 	bond_attach_slave(bond, new_slave);
1436 
1437 	new_slave->delay = 0;
1438 	new_slave->link_failure_count = 0;
1439 
1440 	bond_compute_features(bond);
1441 
1442 	new_slave->last_arp_rx = jiffies;
1443 
1444 	if (bond->params.miimon && !bond->params.use_carrier) {
1445 		link_reporting = bond_check_dev_link(bond, slave_dev, 1);
1446 
1447 		if ((link_reporting == -1) && !bond->params.arp_interval) {
1448 			/*
1449 			 * miimon is set but a bonded network driver
1450 			 * does not support ETHTOOL/MII and
1451 			 * arp_interval is not set.  Note: if
1452 			 * use_carrier is enabled, we will never go
1453 			 * here (because netif_carrier is always
1454 			 * supported); thus, we don't need to change
1455 			 * the messages for netif_carrier.
1456 			 */
1457 			printk(KERN_WARNING DRV_NAME
1458 			       ": %s: Warning: MII and ETHTOOL support not "
1459 			       "available for interface %s, and "
1460 			       "arp_interval/arp_ip_target module parameters "
1461 			       "not specified, thus bonding will not detect "
1462 			       "link failures! see bonding.txt for details.\n",
1463 			       bond_dev->name, slave_dev->name);
1464 		} else if (link_reporting == -1) {
1465 			/* unable get link status using mii/ethtool */
1466 			printk(KERN_WARNING DRV_NAME
1467 			       ": %s: Warning: can't get link status from "
1468 			       "interface %s; the network driver associated "
1469 			       "with this interface does not support MII or "
1470 			       "ETHTOOL link status reporting, thus miimon "
1471 			       "has no effect on this interface.\n",
1472 			       bond_dev->name, slave_dev->name);
1473 		}
1474 	}
1475 
1476 	/* check for initial state */
1477 	if (!bond->params.miimon ||
1478 	    (bond_check_dev_link(bond, slave_dev, 0) == BMSR_LSTATUS)) {
1479 		if (bond->params.updelay) {
1480 			dprintk("Initial state of slave_dev is "
1481 				"BOND_LINK_BACK\n");
1482 			new_slave->link  = BOND_LINK_BACK;
1483 			new_slave->delay = bond->params.updelay;
1484 		} else {
1485 			dprintk("Initial state of slave_dev is "
1486 				"BOND_LINK_UP\n");
1487 			new_slave->link  = BOND_LINK_UP;
1488 		}
1489 		new_slave->jiffies = jiffies;
1490 	} else {
1491 		dprintk("Initial state of slave_dev is "
1492 			"BOND_LINK_DOWN\n");
1493 		new_slave->link  = BOND_LINK_DOWN;
1494 	}
1495 
1496 	if (bond_update_speed_duplex(new_slave) &&
1497 	    (new_slave->link != BOND_LINK_DOWN)) {
1498 		printk(KERN_WARNING DRV_NAME
1499 		       ": %s: Warning: failed to get speed and duplex from %s, "
1500 		       "assumed to be 100Mb/sec and Full.\n",
1501 		       bond_dev->name, new_slave->dev->name);
1502 
1503 		if (bond->params.mode == BOND_MODE_8023AD) {
1504 			printk(KERN_WARNING DRV_NAME
1505 			       ": %s: Warning: Operation of 802.3ad mode requires ETHTOOL "
1506 			       "support in base driver for proper aggregator "
1507 			       "selection.\n", bond_dev->name);
1508 		}
1509 	}
1510 
1511 	if (USES_PRIMARY(bond->params.mode) && bond->params.primary[0]) {
1512 		/* if there is a primary slave, remember it */
1513 		if (strcmp(bond->params.primary, new_slave->dev->name) == 0) {
1514 			bond->primary_slave = new_slave;
1515 		}
1516 	}
1517 
1518 	switch (bond->params.mode) {
1519 	case BOND_MODE_ACTIVEBACKUP:
1520 		bond_set_slave_inactive_flags(new_slave);
1521 		bond_select_active_slave(bond);
1522 		break;
1523 	case BOND_MODE_8023AD:
1524 		/* in 802.3ad mode, the internal mechanism
1525 		 * will activate the slaves in the selected
1526 		 * aggregator
1527 		 */
1528 		bond_set_slave_inactive_flags(new_slave);
1529 		/* if this is the first slave */
1530 		if (bond->slave_cnt == 1) {
1531 			SLAVE_AD_INFO(new_slave).id = 1;
1532 			/* Initialize AD with the number of times that the AD timer is called in 1 second
1533 			 * can be called only after the mac address of the bond is set
1534 			 */
1535 			bond_3ad_initialize(bond, 1000/AD_TIMER_INTERVAL,
1536 					    bond->params.lacp_fast);
1537 		} else {
1538 			SLAVE_AD_INFO(new_slave).id =
1539 				SLAVE_AD_INFO(new_slave->prev).id + 1;
1540 		}
1541 
1542 		bond_3ad_bind_slave(new_slave);
1543 		break;
1544 	case BOND_MODE_TLB:
1545 	case BOND_MODE_ALB:
1546 		new_slave->state = BOND_STATE_ACTIVE;
1547 		if ((!bond->curr_active_slave) &&
1548 		    (new_slave->link != BOND_LINK_DOWN)) {
1549 			/* first slave or no active slave yet, and this link
1550 			 * is OK, so make this interface the active one
1551 			 */
1552 			bond_change_active_slave(bond, new_slave);
1553 		} else {
1554 			bond_set_slave_inactive_flags(new_slave);
1555 		}
1556 		break;
1557 	default:
1558 		dprintk("This slave is always active in trunk mode\n");
1559 
1560 		/* always active in trunk mode */
1561 		new_slave->state = BOND_STATE_ACTIVE;
1562 
1563 		/* In trunking mode there is little meaning to curr_active_slave
1564 		 * anyway (it holds no special properties of the bond device),
1565 		 * so we can change it without calling change_active_interface()
1566 		 */
1567 		if (!bond->curr_active_slave) {
1568 			bond->curr_active_slave = new_slave;
1569 		}
1570 		break;
1571 	} /* switch(bond_mode) */
1572 
1573 	bond_set_carrier(bond);
1574 
1575 	write_unlock_bh(&bond->lock);
1576 
1577 	res = bond_create_slave_symlinks(bond_dev, slave_dev);
1578 	if (res)
1579 		goto err_unset_master;
1580 
1581 	printk(KERN_INFO DRV_NAME
1582 	       ": %s: enslaving %s as a%s interface with a%s link.\n",
1583 	       bond_dev->name, slave_dev->name,
1584 	       new_slave->state == BOND_STATE_ACTIVE ? "n active" : " backup",
1585 	       new_slave->link != BOND_LINK_DOWN ? "n up" : " down");
1586 
1587 	/* enslave is successful */
1588 	return 0;
1589 
1590 /* Undo stages on error */
1591 err_unset_master:
1592 	netdev_set_master(slave_dev, NULL);
1593 
1594 err_close:
1595 	dev_close(slave_dev);
1596 
1597 err_restore_mac:
1598 	memcpy(addr.sa_data, new_slave->perm_hwaddr, ETH_ALEN);
1599 	addr.sa_family = slave_dev->type;
1600 	dev_set_mac_address(slave_dev, &addr);
1601 
1602 err_free:
1603 	kfree(new_slave);
1604 
1605 err_undo_flags:
1606 	bond_dev->features = old_features;
1607 
1608 	return res;
1609 }
1610 
1611 /*
1612  * Try to release the slave device <slave> from the bond device <master>
1613  * It is legal to access curr_active_slave without a lock because all the function
1614  * is write-locked.
1615  *
1616  * The rules for slave state should be:
1617  *   for Active/Backup:
1618  *     Active stays on all backups go down
1619  *   for Bonded connections:
1620  *     The first up interface should be left on and all others downed.
1621  */
1622 int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
1623 {
1624 	struct bonding *bond = bond_dev->priv;
1625 	struct slave *slave, *oldcurrent;
1626 	struct sockaddr addr;
1627 	int mac_addr_differ;
1628 
1629 	/* slave is not a slave or master is not master of this slave */
1630 	if (!(slave_dev->flags & IFF_SLAVE) ||
1631 	    (slave_dev->master != bond_dev)) {
1632 		printk(KERN_ERR DRV_NAME
1633 		       ": %s: Error: cannot release %s.\n",
1634 		       bond_dev->name, slave_dev->name);
1635 		return -EINVAL;
1636 	}
1637 
1638 	write_lock_bh(&bond->lock);
1639 
1640 	slave = bond_get_slave_by_dev(bond, slave_dev);
1641 	if (!slave) {
1642 		/* not a slave of this bond */
1643 		printk(KERN_INFO DRV_NAME
1644 		       ": %s: %s not enslaved\n",
1645 		       bond_dev->name, slave_dev->name);
1646 		write_unlock_bh(&bond->lock);
1647 		return -EINVAL;
1648 	}
1649 
1650 	mac_addr_differ = memcmp(bond_dev->dev_addr,
1651 				 slave->perm_hwaddr,
1652 				 ETH_ALEN);
1653 	if (!mac_addr_differ && (bond->slave_cnt > 1)) {
1654 		printk(KERN_WARNING DRV_NAME
1655 		       ": %s: Warning: the permanent HWaddr of %s "
1656 		       "- %02X:%02X:%02X:%02X:%02X:%02X - is "
1657 		       "still in use by %s. Set the HWaddr of "
1658 		       "%s to a different address to avoid "
1659 		       "conflicts.\n",
1660 		       bond_dev->name,
1661 		       slave_dev->name,
1662 		       slave->perm_hwaddr[0],
1663 		       slave->perm_hwaddr[1],
1664 		       slave->perm_hwaddr[2],
1665 		       slave->perm_hwaddr[3],
1666 		       slave->perm_hwaddr[4],
1667 		       slave->perm_hwaddr[5],
1668 		       bond_dev->name,
1669 		       slave_dev->name);
1670 	}
1671 
1672 	/* Inform AD package of unbinding of slave. */
1673 	if (bond->params.mode == BOND_MODE_8023AD) {
1674 		/* must be called before the slave is
1675 		 * detached from the list
1676 		 */
1677 		bond_3ad_unbind_slave(slave);
1678 	}
1679 
1680 	printk(KERN_INFO DRV_NAME
1681 	       ": %s: releasing %s interface %s\n",
1682 	       bond_dev->name,
1683 	       (slave->state == BOND_STATE_ACTIVE)
1684 	       ? "active" : "backup",
1685 	       slave_dev->name);
1686 
1687 	oldcurrent = bond->curr_active_slave;
1688 
1689 	bond->current_arp_slave = NULL;
1690 
1691 	/* release the slave from its bond */
1692 	bond_detach_slave(bond, slave);
1693 
1694 	bond_compute_features(bond);
1695 
1696 	if (bond->primary_slave == slave) {
1697 		bond->primary_slave = NULL;
1698 	}
1699 
1700 	if (oldcurrent == slave) {
1701 		bond_change_active_slave(bond, NULL);
1702 	}
1703 
1704 	if ((bond->params.mode == BOND_MODE_TLB) ||
1705 	    (bond->params.mode == BOND_MODE_ALB)) {
1706 		/* Must be called only after the slave has been
1707 		 * detached from the list and the curr_active_slave
1708 		 * has been cleared (if our_slave == old_current),
1709 		 * but before a new active slave is selected.
1710 		 */
1711 		bond_alb_deinit_slave(bond, slave);
1712 	}
1713 
1714 	if (oldcurrent == slave)
1715 		bond_select_active_slave(bond);
1716 
1717 	if (bond->slave_cnt == 0) {
1718 		bond_set_carrier(bond);
1719 
1720 		/* if the last slave was removed, zero the mac address
1721 		 * of the master so it will be set by the application
1722 		 * to the mac address of the first slave
1723 		 */
1724 		memset(bond_dev->dev_addr, 0, bond_dev->addr_len);
1725 
1726 		if (list_empty(&bond->vlan_list)) {
1727 			bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
1728 		} else {
1729 			printk(KERN_WARNING DRV_NAME
1730 			       ": %s: Warning: clearing HW address of %s while it "
1731 			       "still has VLANs.\n",
1732 			       bond_dev->name, bond_dev->name);
1733 			printk(KERN_WARNING DRV_NAME
1734 			       ": %s: When re-adding slaves, make sure the bond's "
1735 			       "HW address matches its VLANs'.\n",
1736 			       bond_dev->name);
1737 		}
1738 	} else if ((bond_dev->features & NETIF_F_VLAN_CHALLENGED) &&
1739 		   !bond_has_challenged_slaves(bond)) {
1740 		printk(KERN_INFO DRV_NAME
1741 		       ": %s: last VLAN challenged slave %s "
1742 		       "left bond %s. VLAN blocking is removed\n",
1743 		       bond_dev->name, slave_dev->name, bond_dev->name);
1744 		bond_dev->features &= ~NETIF_F_VLAN_CHALLENGED;
1745 	}
1746 
1747 	write_unlock_bh(&bond->lock);
1748 
1749 	/* must do this from outside any spinlocks */
1750 	bond_destroy_slave_symlinks(bond_dev, slave_dev);
1751 
1752 	bond_del_vlans_from_slave(bond, slave_dev);
1753 
1754 	/* If the mode USES_PRIMARY, then we should only remove its
1755 	 * promisc and mc settings if it was the curr_active_slave, but that was
1756 	 * already taken care of above when we detached the slave
1757 	 */
1758 	if (!USES_PRIMARY(bond->params.mode)) {
1759 		/* unset promiscuity level from slave */
1760 		if (bond_dev->flags & IFF_PROMISC) {
1761 			dev_set_promiscuity(slave_dev, -1);
1762 		}
1763 
1764 		/* unset allmulti level from slave */
1765 		if (bond_dev->flags & IFF_ALLMULTI) {
1766 			dev_set_allmulti(slave_dev, -1);
1767 		}
1768 
1769 		/* flush master's mc_list from slave */
1770 		bond_mc_list_flush(bond_dev, slave_dev);
1771 	}
1772 
1773 	netdev_set_master(slave_dev, NULL);
1774 
1775 	/* close slave before restoring its mac address */
1776 	dev_close(slave_dev);
1777 
1778 	/* restore original ("permanent") mac address */
1779 	memcpy(addr.sa_data, slave->perm_hwaddr, ETH_ALEN);
1780 	addr.sa_family = slave_dev->type;
1781 	dev_set_mac_address(slave_dev, &addr);
1782 
1783 	slave_dev->priv_flags &= ~(IFF_MASTER_8023AD | IFF_MASTER_ALB |
1784 				   IFF_SLAVE_INACTIVE | IFF_BONDING |
1785 				   IFF_SLAVE_NEEDARP);
1786 
1787 	kfree(slave);
1788 
1789 	return 0;  /* deletion OK */
1790 }
1791 
1792 /*
1793  * This function releases all slaves.
1794  */
1795 static int bond_release_all(struct net_device *bond_dev)
1796 {
1797 	struct bonding *bond = bond_dev->priv;
1798 	struct slave *slave;
1799 	struct net_device *slave_dev;
1800 	struct sockaddr addr;
1801 
1802 	write_lock_bh(&bond->lock);
1803 
1804 	netif_carrier_off(bond_dev);
1805 
1806 	if (bond->slave_cnt == 0) {
1807 		goto out;
1808 	}
1809 
1810 	bond->current_arp_slave = NULL;
1811 	bond->primary_slave = NULL;
1812 	bond_change_active_slave(bond, NULL);
1813 
1814 	while ((slave = bond->first_slave) != NULL) {
1815 		/* Inform AD package of unbinding of slave
1816 		 * before slave is detached from the list.
1817 		 */
1818 		if (bond->params.mode == BOND_MODE_8023AD) {
1819 			bond_3ad_unbind_slave(slave);
1820 		}
1821 
1822 		slave_dev = slave->dev;
1823 		bond_detach_slave(bond, slave);
1824 
1825 		if ((bond->params.mode == BOND_MODE_TLB) ||
1826 		    (bond->params.mode == BOND_MODE_ALB)) {
1827 			/* must be called only after the slave
1828 			 * has been detached from the list
1829 			 */
1830 			bond_alb_deinit_slave(bond, slave);
1831 		}
1832 
1833 		bond_compute_features(bond);
1834 
1835 		/* now that the slave is detached, unlock and perform
1836 		 * all the undo steps that should not be called from
1837 		 * within a lock.
1838 		 */
1839 		write_unlock_bh(&bond->lock);
1840 
1841 		bond_destroy_slave_symlinks(bond_dev, slave_dev);
1842 		bond_del_vlans_from_slave(bond, slave_dev);
1843 
1844 		/* If the mode USES_PRIMARY, then we should only remove its
1845 		 * promisc and mc settings if it was the curr_active_slave, but that was
1846 		 * already taken care of above when we detached the slave
1847 		 */
1848 		if (!USES_PRIMARY(bond->params.mode)) {
1849 			/* unset promiscuity level from slave */
1850 			if (bond_dev->flags & IFF_PROMISC) {
1851 				dev_set_promiscuity(slave_dev, -1);
1852 			}
1853 
1854 			/* unset allmulti level from slave */
1855 			if (bond_dev->flags & IFF_ALLMULTI) {
1856 				dev_set_allmulti(slave_dev, -1);
1857 			}
1858 
1859 			/* flush master's mc_list from slave */
1860 			bond_mc_list_flush(bond_dev, slave_dev);
1861 		}
1862 
1863 		netdev_set_master(slave_dev, NULL);
1864 
1865 		/* close slave before restoring its mac address */
1866 		dev_close(slave_dev);
1867 
1868 		/* restore original ("permanent") mac address*/
1869 		memcpy(addr.sa_data, slave->perm_hwaddr, ETH_ALEN);
1870 		addr.sa_family = slave_dev->type;
1871 		dev_set_mac_address(slave_dev, &addr);
1872 
1873 		slave_dev->priv_flags &= ~(IFF_MASTER_8023AD | IFF_MASTER_ALB |
1874 					   IFF_SLAVE_INACTIVE);
1875 
1876 		kfree(slave);
1877 
1878 		/* re-acquire the lock before getting the next slave */
1879 		write_lock_bh(&bond->lock);
1880 	}
1881 
1882 	/* zero the mac address of the master so it will be
1883 	 * set by the application to the mac address of the
1884 	 * first slave
1885 	 */
1886 	memset(bond_dev->dev_addr, 0, bond_dev->addr_len);
1887 
1888 	if (list_empty(&bond->vlan_list)) {
1889 		bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
1890 	} else {
1891 		printk(KERN_WARNING DRV_NAME
1892 		       ": %s: Warning: clearing HW address of %s while it "
1893 		       "still has VLANs.\n",
1894 		       bond_dev->name, bond_dev->name);
1895 		printk(KERN_WARNING DRV_NAME
1896 		       ": %s: When re-adding slaves, make sure the bond's "
1897 		       "HW address matches its VLANs'.\n",
1898 		       bond_dev->name);
1899 	}
1900 
1901 	printk(KERN_INFO DRV_NAME
1902 	       ": %s: released all slaves\n",
1903 	       bond_dev->name);
1904 
1905 out:
1906 	write_unlock_bh(&bond->lock);
1907 
1908 	return 0;
1909 }
1910 
1911 /*
1912  * This function changes the active slave to slave <slave_dev>.
1913  * It returns -EINVAL in the following cases.
1914  *  - <slave_dev> is not found in the list.
1915  *  - There is not active slave now.
1916  *  - <slave_dev> is already active.
1917  *  - The link state of <slave_dev> is not BOND_LINK_UP.
1918  *  - <slave_dev> is not running.
1919  * In these cases, this fuction does nothing.
1920  * In the other cases, currnt_slave pointer is changed and 0 is returned.
1921  */
1922 static int bond_ioctl_change_active(struct net_device *bond_dev, struct net_device *slave_dev)
1923 {
1924 	struct bonding *bond = bond_dev->priv;
1925 	struct slave *old_active = NULL;
1926 	struct slave *new_active = NULL;
1927 	int res = 0;
1928 
1929 	if (!USES_PRIMARY(bond->params.mode)) {
1930 		return -EINVAL;
1931 	}
1932 
1933 	/* Verify that master_dev is indeed the master of slave_dev */
1934 	if (!(slave_dev->flags & IFF_SLAVE) ||
1935 	    (slave_dev->master != bond_dev)) {
1936 		return -EINVAL;
1937 	}
1938 
1939 	write_lock_bh(&bond->lock);
1940 
1941 	old_active = bond->curr_active_slave;
1942 	new_active = bond_get_slave_by_dev(bond, slave_dev);
1943 
1944 	/*
1945 	 * Changing to the current active: do nothing; return success.
1946 	 */
1947 	if (new_active && (new_active == old_active)) {
1948 		write_unlock_bh(&bond->lock);
1949 		return 0;
1950 	}
1951 
1952 	if ((new_active) &&
1953 	    (old_active) &&
1954 	    (new_active->link == BOND_LINK_UP) &&
1955 	    IS_UP(new_active->dev)) {
1956 		bond_change_active_slave(bond, new_active);
1957 	} else {
1958 		res = -EINVAL;
1959 	}
1960 
1961 	write_unlock_bh(&bond->lock);
1962 
1963 	return res;
1964 }
1965 
1966 static int bond_info_query(struct net_device *bond_dev, struct ifbond *info)
1967 {
1968 	struct bonding *bond = bond_dev->priv;
1969 
1970 	info->bond_mode = bond->params.mode;
1971 	info->miimon = bond->params.miimon;
1972 
1973 	read_lock_bh(&bond->lock);
1974 	info->num_slaves = bond->slave_cnt;
1975 	read_unlock_bh(&bond->lock);
1976 
1977 	return 0;
1978 }
1979 
1980 static int bond_slave_info_query(struct net_device *bond_dev, struct ifslave *info)
1981 {
1982 	struct bonding *bond = bond_dev->priv;
1983 	struct slave *slave;
1984 	int i, found = 0;
1985 
1986 	if (info->slave_id < 0) {
1987 		return -ENODEV;
1988 	}
1989 
1990 	read_lock_bh(&bond->lock);
1991 
1992 	bond_for_each_slave(bond, slave, i) {
1993 		if (i == (int)info->slave_id) {
1994 			found = 1;
1995 			break;
1996 		}
1997 	}
1998 
1999 	read_unlock_bh(&bond->lock);
2000 
2001 	if (found) {
2002 		strcpy(info->slave_name, slave->dev->name);
2003 		info->link = slave->link;
2004 		info->state = slave->state;
2005 		info->link_failure_count = slave->link_failure_count;
2006 	} else {
2007 		return -ENODEV;
2008 	}
2009 
2010 	return 0;
2011 }
2012 
2013 /*-------------------------------- Monitoring -------------------------------*/
2014 
2015 /* this function is called regularly to monitor each slave's link. */
2016 void bond_mii_monitor(struct net_device *bond_dev)
2017 {
2018 	struct bonding *bond = bond_dev->priv;
2019 	struct slave *slave, *oldcurrent;
2020 	int do_failover = 0;
2021 	int delta_in_ticks;
2022 	int i;
2023 
2024 	read_lock(&bond->lock);
2025 
2026 	delta_in_ticks = (bond->params.miimon * HZ) / 1000;
2027 
2028 	if (bond->kill_timers) {
2029 		goto out;
2030 	}
2031 
2032 	if (bond->slave_cnt == 0) {
2033 		goto re_arm;
2034 	}
2035 
2036 	/* we will try to read the link status of each of our slaves, and
2037 	 * set their IFF_RUNNING flag appropriately. For each slave not
2038 	 * supporting MII status, we won't do anything so that a user-space
2039 	 * program could monitor the link itself if needed.
2040 	 */
2041 
2042 	read_lock(&bond->curr_slave_lock);
2043 	oldcurrent = bond->curr_active_slave;
2044 	read_unlock(&bond->curr_slave_lock);
2045 
2046 	bond_for_each_slave(bond, slave, i) {
2047 		struct net_device *slave_dev = slave->dev;
2048 		int link_state;
2049 		u16 old_speed = slave->speed;
2050 		u8 old_duplex = slave->duplex;
2051 
2052 		link_state = bond_check_dev_link(bond, slave_dev, 0);
2053 
2054 		switch (slave->link) {
2055 		case BOND_LINK_UP:	/* the link was up */
2056 			if (link_state == BMSR_LSTATUS) {
2057 				/* link stays up, nothing more to do */
2058 				break;
2059 			} else { /* link going down */
2060 				slave->link  = BOND_LINK_FAIL;
2061 				slave->delay = bond->params.downdelay;
2062 
2063 				if (slave->link_failure_count < UINT_MAX) {
2064 					slave->link_failure_count++;
2065 				}
2066 
2067 				if (bond->params.downdelay) {
2068 					printk(KERN_INFO DRV_NAME
2069 					       ": %s: link status down for %s "
2070 					       "interface %s, disabling it in "
2071 					       "%d ms.\n",
2072 					       bond_dev->name,
2073 					       IS_UP(slave_dev)
2074 					       ? ((bond->params.mode == BOND_MODE_ACTIVEBACKUP)
2075 						  ? ((slave == oldcurrent)
2076 						     ? "active " : "backup ")
2077 						  : "")
2078 					       : "idle ",
2079 					       slave_dev->name,
2080 					       bond->params.downdelay * bond->params.miimon);
2081 				}
2082 			}
2083 			/* no break ! fall through the BOND_LINK_FAIL test to
2084 			   ensure proper action to be taken
2085 			*/
2086 		case BOND_LINK_FAIL:	/* the link has just gone down */
2087 			if (link_state != BMSR_LSTATUS) {
2088 				/* link stays down */
2089 				if (slave->delay <= 0) {
2090 					/* link down for too long time */
2091 					slave->link = BOND_LINK_DOWN;
2092 
2093 					/* in active/backup mode, we must
2094 					 * completely disable this interface
2095 					 */
2096 					if ((bond->params.mode == BOND_MODE_ACTIVEBACKUP) ||
2097 					    (bond->params.mode == BOND_MODE_8023AD)) {
2098 						bond_set_slave_inactive_flags(slave);
2099 					}
2100 
2101 					printk(KERN_INFO DRV_NAME
2102 					       ": %s: link status definitely "
2103 					       "down for interface %s, "
2104 					       "disabling it\n",
2105 					       bond_dev->name,
2106 					       slave_dev->name);
2107 
2108 					/* notify ad that the link status has changed */
2109 					if (bond->params.mode == BOND_MODE_8023AD) {
2110 						bond_3ad_handle_link_change(slave, BOND_LINK_DOWN);
2111 					}
2112 
2113 					if ((bond->params.mode == BOND_MODE_TLB) ||
2114 					    (bond->params.mode == BOND_MODE_ALB)) {
2115 						bond_alb_handle_link_change(bond, slave, BOND_LINK_DOWN);
2116 					}
2117 
2118 					if (slave == oldcurrent) {
2119 						do_failover = 1;
2120 					}
2121 				} else {
2122 					slave->delay--;
2123 				}
2124 			} else {
2125 				/* link up again */
2126 				slave->link  = BOND_LINK_UP;
2127 				slave->jiffies = jiffies;
2128 				printk(KERN_INFO DRV_NAME
2129 				       ": %s: link status up again after %d "
2130 				       "ms for interface %s.\n",
2131 				       bond_dev->name,
2132 				       (bond->params.downdelay - slave->delay) * bond->params.miimon,
2133 				       slave_dev->name);
2134 			}
2135 			break;
2136 		case BOND_LINK_DOWN:	/* the link was down */
2137 			if (link_state != BMSR_LSTATUS) {
2138 				/* the link stays down, nothing more to do */
2139 				break;
2140 			} else {	/* link going up */
2141 				slave->link  = BOND_LINK_BACK;
2142 				slave->delay = bond->params.updelay;
2143 
2144 				if (bond->params.updelay) {
2145 					/* if updelay == 0, no need to
2146 					   advertise about a 0 ms delay */
2147 					printk(KERN_INFO DRV_NAME
2148 					       ": %s: link status up for "
2149 					       "interface %s, enabling it "
2150 					       "in %d ms.\n",
2151 					       bond_dev->name,
2152 					       slave_dev->name,
2153 					       bond->params.updelay * bond->params.miimon);
2154 				}
2155 			}
2156 			/* no break ! fall through the BOND_LINK_BACK state in
2157 			   case there's something to do.
2158 			*/
2159 		case BOND_LINK_BACK:	/* the link has just come back */
2160 			if (link_state != BMSR_LSTATUS) {
2161 				/* link down again */
2162 				slave->link  = BOND_LINK_DOWN;
2163 
2164 				printk(KERN_INFO DRV_NAME
2165 				       ": %s: link status down again after %d "
2166 				       "ms for interface %s.\n",
2167 				       bond_dev->name,
2168 				       (bond->params.updelay - slave->delay) * bond->params.miimon,
2169 				       slave_dev->name);
2170 			} else {
2171 				/* link stays up */
2172 				if (slave->delay == 0) {
2173 					/* now the link has been up for long time enough */
2174 					slave->link = BOND_LINK_UP;
2175 					slave->jiffies = jiffies;
2176 
2177 					if (bond->params.mode == BOND_MODE_8023AD) {
2178 						/* prevent it from being the active one */
2179 						slave->state = BOND_STATE_BACKUP;
2180 					} else if (bond->params.mode != BOND_MODE_ACTIVEBACKUP) {
2181 						/* make it immediately active */
2182 						slave->state = BOND_STATE_ACTIVE;
2183 					} else if (slave != bond->primary_slave) {
2184 						/* prevent it from being the active one */
2185 						slave->state = BOND_STATE_BACKUP;
2186 					}
2187 
2188 					printk(KERN_INFO DRV_NAME
2189 					       ": %s: link status definitely "
2190 					       "up for interface %s.\n",
2191 					       bond_dev->name,
2192 					       slave_dev->name);
2193 
2194 					/* notify ad that the link status has changed */
2195 					if (bond->params.mode == BOND_MODE_8023AD) {
2196 						bond_3ad_handle_link_change(slave, BOND_LINK_UP);
2197 					}
2198 
2199 					if ((bond->params.mode == BOND_MODE_TLB) ||
2200 					    (bond->params.mode == BOND_MODE_ALB)) {
2201 						bond_alb_handle_link_change(bond, slave, BOND_LINK_UP);
2202 					}
2203 
2204 					if ((!oldcurrent) ||
2205 					    (slave == bond->primary_slave)) {
2206 						do_failover = 1;
2207 					}
2208 				} else {
2209 					slave->delay--;
2210 				}
2211 			}
2212 			break;
2213 		default:
2214 			/* Should not happen */
2215 			printk(KERN_ERR DRV_NAME
2216 			       ": %s: Error: %s Illegal value (link=%d)\n",
2217 			       bond_dev->name,
2218 			       slave->dev->name,
2219 			       slave->link);
2220 			goto out;
2221 		} /* end of switch (slave->link) */
2222 
2223 		bond_update_speed_duplex(slave);
2224 
2225 		if (bond->params.mode == BOND_MODE_8023AD) {
2226 			if (old_speed != slave->speed) {
2227 				bond_3ad_adapter_speed_changed(slave);
2228 			}
2229 
2230 			if (old_duplex != slave->duplex) {
2231 				bond_3ad_adapter_duplex_changed(slave);
2232 			}
2233 		}
2234 
2235 	} /* end of for */
2236 
2237 	if (do_failover) {
2238 		write_lock(&bond->curr_slave_lock);
2239 
2240 		bond_select_active_slave(bond);
2241 
2242 		write_unlock(&bond->curr_slave_lock);
2243 	} else
2244 		bond_set_carrier(bond);
2245 
2246 re_arm:
2247 	if (bond->params.miimon) {
2248 		mod_timer(&bond->mii_timer, jiffies + delta_in_ticks);
2249 	}
2250 out:
2251 	read_unlock(&bond->lock);
2252 }
2253 
2254 
2255 static u32 bond_glean_dev_ip(struct net_device *dev)
2256 {
2257 	struct in_device *idev;
2258 	struct in_ifaddr *ifa;
2259 	__be32 addr = 0;
2260 
2261 	if (!dev)
2262 		return 0;
2263 
2264 	rcu_read_lock();
2265 	idev = __in_dev_get_rcu(dev);
2266 	if (!idev)
2267 		goto out;
2268 
2269 	ifa = idev->ifa_list;
2270 	if (!ifa)
2271 		goto out;
2272 
2273 	addr = ifa->ifa_local;
2274 out:
2275 	rcu_read_unlock();
2276 	return addr;
2277 }
2278 
2279 static int bond_has_ip(struct bonding *bond)
2280 {
2281 	struct vlan_entry *vlan, *vlan_next;
2282 
2283 	if (bond->master_ip)
2284 		return 1;
2285 
2286 	if (list_empty(&bond->vlan_list))
2287 		return 0;
2288 
2289 	list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
2290 				 vlan_list) {
2291 		if (vlan->vlan_ip)
2292 			return 1;
2293 	}
2294 
2295 	return 0;
2296 }
2297 
2298 static int bond_has_this_ip(struct bonding *bond, u32 ip)
2299 {
2300 	struct vlan_entry *vlan, *vlan_next;
2301 
2302 	if (ip == bond->master_ip)
2303 		return 1;
2304 
2305 	if (list_empty(&bond->vlan_list))
2306 		return 0;
2307 
2308 	list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
2309 				 vlan_list) {
2310 		if (ip == vlan->vlan_ip)
2311 			return 1;
2312 	}
2313 
2314 	return 0;
2315 }
2316 
2317 /*
2318  * We go to the (large) trouble of VLAN tagging ARP frames because
2319  * switches in VLAN mode (especially if ports are configured as
2320  * "native" to a VLAN) might not pass non-tagged frames.
2321  */
2322 static void bond_arp_send(struct net_device *slave_dev, int arp_op, u32 dest_ip, u32 src_ip, unsigned short vlan_id)
2323 {
2324 	struct sk_buff *skb;
2325 
2326 	dprintk("arp %d on slave %s: dst %x src %x vid %d\n", arp_op,
2327 	       slave_dev->name, dest_ip, src_ip, vlan_id);
2328 
2329 	skb = arp_create(arp_op, ETH_P_ARP, dest_ip, slave_dev, src_ip,
2330 			 NULL, slave_dev->dev_addr, NULL);
2331 
2332 	if (!skb) {
2333 		printk(KERN_ERR DRV_NAME ": ARP packet allocation failed\n");
2334 		return;
2335 	}
2336 	if (vlan_id) {
2337 		skb = vlan_put_tag(skb, vlan_id);
2338 		if (!skb) {
2339 			printk(KERN_ERR DRV_NAME ": failed to insert VLAN tag\n");
2340 			return;
2341 		}
2342 	}
2343 	arp_xmit(skb);
2344 }
2345 
2346 
2347 static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
2348 {
2349 	int i, vlan_id, rv;
2350 	u32 *targets = bond->params.arp_targets;
2351 	struct vlan_entry *vlan, *vlan_next;
2352 	struct net_device *vlan_dev;
2353 	struct flowi fl;
2354 	struct rtable *rt;
2355 
2356 	for (i = 0; (i < BOND_MAX_ARP_TARGETS); i++) {
2357 		if (!targets[i])
2358 			continue;
2359 		dprintk("basa: target %x\n", targets[i]);
2360 		if (list_empty(&bond->vlan_list)) {
2361 			dprintk("basa: empty vlan: arp_send\n");
2362 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2363 				      bond->master_ip, 0);
2364 			continue;
2365 		}
2366 
2367 		/*
2368 		 * If VLANs are configured, we do a route lookup to
2369 		 * determine which VLAN interface would be used, so we
2370 		 * can tag the ARP with the proper VLAN tag.
2371 		 */
2372 		memset(&fl, 0, sizeof(fl));
2373 		fl.fl4_dst = targets[i];
2374 		fl.fl4_tos = RTO_ONLINK;
2375 
2376 		rv = ip_route_output_key(&rt, &fl);
2377 		if (rv) {
2378 			if (net_ratelimit()) {
2379 				printk(KERN_WARNING DRV_NAME
2380 			     ": %s: no route to arp_ip_target %u.%u.%u.%u\n",
2381 				       bond->dev->name, NIPQUAD(fl.fl4_dst));
2382 			}
2383 			continue;
2384 		}
2385 
2386 		/*
2387 		 * This target is not on a VLAN
2388 		 */
2389 		if (rt->u.dst.dev == bond->dev) {
2390 			ip_rt_put(rt);
2391 			dprintk("basa: rtdev == bond->dev: arp_send\n");
2392 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2393 				      bond->master_ip, 0);
2394 			continue;
2395 		}
2396 
2397 		vlan_id = 0;
2398 		list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
2399 					 vlan_list) {
2400 			vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
2401 			if (vlan_dev == rt->u.dst.dev) {
2402 				vlan_id = vlan->vlan_id;
2403 				dprintk("basa: vlan match on %s %d\n",
2404 				       vlan_dev->name, vlan_id);
2405 				break;
2406 			}
2407 		}
2408 
2409 		if (vlan_id) {
2410 			ip_rt_put(rt);
2411 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2412 				      vlan->vlan_ip, vlan_id);
2413 			continue;
2414 		}
2415 
2416 		if (net_ratelimit()) {
2417 			printk(KERN_WARNING DRV_NAME
2418 	       ": %s: no path to arp_ip_target %u.%u.%u.%u via rt.dev %s\n",
2419 			       bond->dev->name, NIPQUAD(fl.fl4_dst),
2420 			       rt->u.dst.dev ? rt->u.dst.dev->name : "NULL");
2421 		}
2422 		ip_rt_put(rt);
2423 	}
2424 }
2425 
2426 /*
2427  * Kick out a gratuitous ARP for an IP on the bonding master plus one
2428  * for each VLAN above us.
2429  */
2430 static void bond_send_gratuitous_arp(struct bonding *bond)
2431 {
2432 	struct slave *slave = bond->curr_active_slave;
2433 	struct vlan_entry *vlan;
2434 	struct net_device *vlan_dev;
2435 
2436 	dprintk("bond_send_grat_arp: bond %s slave %s\n", bond->dev->name,
2437 				slave ? slave->dev->name : "NULL");
2438 	if (!slave)
2439 		return;
2440 
2441 	if (bond->master_ip) {
2442 		bond_arp_send(slave->dev, ARPOP_REPLY, bond->master_ip,
2443 				  bond->master_ip, 0);
2444 	}
2445 
2446 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
2447 		vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
2448 		if (vlan->vlan_ip) {
2449 			bond_arp_send(slave->dev, ARPOP_REPLY, vlan->vlan_ip,
2450 				      vlan->vlan_ip, vlan->vlan_id);
2451 		}
2452 	}
2453 }
2454 
2455 static void bond_validate_arp(struct bonding *bond, struct slave *slave, u32 sip, u32 tip)
2456 {
2457 	int i;
2458 	u32 *targets = bond->params.arp_targets;
2459 
2460 	targets = bond->params.arp_targets;
2461 	for (i = 0; (i < BOND_MAX_ARP_TARGETS) && targets[i]; i++) {
2462 		dprintk("bva: sip %u.%u.%u.%u tip %u.%u.%u.%u t[%d] "
2463 			"%u.%u.%u.%u bhti(tip) %d\n",
2464 		       NIPQUAD(sip), NIPQUAD(tip), i, NIPQUAD(targets[i]),
2465 		       bond_has_this_ip(bond, tip));
2466 		if (sip == targets[i]) {
2467 			if (bond_has_this_ip(bond, tip))
2468 				slave->last_arp_rx = jiffies;
2469 			return;
2470 		}
2471 	}
2472 }
2473 
2474 static int bond_arp_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
2475 {
2476 	struct arphdr *arp;
2477 	struct slave *slave;
2478 	struct bonding *bond;
2479 	unsigned char *arp_ptr;
2480 	u32 sip, tip;
2481 
2482 	if (!(dev->priv_flags & IFF_BONDING) || !(dev->flags & IFF_MASTER))
2483 		goto out;
2484 
2485 	bond = dev->priv;
2486 	read_lock(&bond->lock);
2487 
2488 	dprintk("bond_arp_rcv: bond %s skb->dev %s orig_dev %s\n",
2489 		bond->dev->name, skb->dev ? skb->dev->name : "NULL",
2490 		orig_dev ? orig_dev->name : "NULL");
2491 
2492 	slave = bond_get_slave_by_dev(bond, orig_dev);
2493 	if (!slave || !slave_do_arp_validate(bond, slave))
2494 		goto out_unlock;
2495 
2496 	/* ARP header, plus 2 device addresses, plus 2 IP addresses.  */
2497 	if (!pskb_may_pull(skb, (sizeof(struct arphdr) +
2498 				 (2 * dev->addr_len) +
2499 				 (2 * sizeof(u32)))))
2500 		goto out_unlock;
2501 
2502 	arp = skb->nh.arph;
2503 	if (arp->ar_hln != dev->addr_len ||
2504 	    skb->pkt_type == PACKET_OTHERHOST ||
2505 	    skb->pkt_type == PACKET_LOOPBACK ||
2506 	    arp->ar_hrd != htons(ARPHRD_ETHER) ||
2507 	    arp->ar_pro != htons(ETH_P_IP) ||
2508 	    arp->ar_pln != 4)
2509 		goto out_unlock;
2510 
2511 	arp_ptr = (unsigned char *)(arp + 1);
2512 	arp_ptr += dev->addr_len;
2513 	memcpy(&sip, arp_ptr, 4);
2514 	arp_ptr += 4 + dev->addr_len;
2515 	memcpy(&tip, arp_ptr, 4);
2516 
2517 	dprintk("bond_arp_rcv: %s %s/%d av %d sv %d sip %u.%u.%u.%u"
2518 		" tip %u.%u.%u.%u\n", bond->dev->name, slave->dev->name,
2519 		slave->state, bond->params.arp_validate,
2520 		slave_do_arp_validate(bond, slave), NIPQUAD(sip), NIPQUAD(tip));
2521 
2522 	/*
2523 	 * Backup slaves won't see the ARP reply, but do come through
2524 	 * here for each ARP probe (so we swap the sip/tip to validate
2525 	 * the probe).  In a "redundant switch, common router" type of
2526 	 * configuration, the ARP probe will (hopefully) travel from
2527 	 * the active, through one switch, the router, then the other
2528 	 * switch before reaching the backup.
2529 	 */
2530 	if (slave->state == BOND_STATE_ACTIVE)
2531 		bond_validate_arp(bond, slave, sip, tip);
2532 	else
2533 		bond_validate_arp(bond, slave, tip, sip);
2534 
2535 out_unlock:
2536 	read_unlock(&bond->lock);
2537 out:
2538 	dev_kfree_skb(skb);
2539 	return NET_RX_SUCCESS;
2540 }
2541 
2542 /*
2543  * this function is called regularly to monitor each slave's link
2544  * ensuring that traffic is being sent and received when arp monitoring
2545  * is used in load-balancing mode. if the adapter has been dormant, then an
2546  * arp is transmitted to generate traffic. see activebackup_arp_monitor for
2547  * arp monitoring in active backup mode.
2548  */
2549 void bond_loadbalance_arp_mon(struct net_device *bond_dev)
2550 {
2551 	struct bonding *bond = bond_dev->priv;
2552 	struct slave *slave, *oldcurrent;
2553 	int do_failover = 0;
2554 	int delta_in_ticks;
2555 	int i;
2556 
2557 	read_lock(&bond->lock);
2558 
2559 	delta_in_ticks = (bond->params.arp_interval * HZ) / 1000;
2560 
2561 	if (bond->kill_timers) {
2562 		goto out;
2563 	}
2564 
2565 	if (bond->slave_cnt == 0) {
2566 		goto re_arm;
2567 	}
2568 
2569 	read_lock(&bond->curr_slave_lock);
2570 	oldcurrent = bond->curr_active_slave;
2571 	read_unlock(&bond->curr_slave_lock);
2572 
2573 	/* see if any of the previous devices are up now (i.e. they have
2574 	 * xmt and rcv traffic). the curr_active_slave does not come into
2575 	 * the picture unless it is null. also, slave->jiffies is not needed
2576 	 * here because we send an arp on each slave and give a slave as
2577 	 * long as it needs to get the tx/rx within the delta.
2578 	 * TODO: what about up/down delay in arp mode? it wasn't here before
2579 	 *       so it can wait
2580 	 */
2581 	bond_for_each_slave(bond, slave, i) {
2582 		if (slave->link != BOND_LINK_UP) {
2583 			if (((jiffies - slave->dev->trans_start) <= delta_in_ticks) &&
2584 			    ((jiffies - slave->dev->last_rx) <= delta_in_ticks)) {
2585 
2586 				slave->link  = BOND_LINK_UP;
2587 				slave->state = BOND_STATE_ACTIVE;
2588 
2589 				/* primary_slave has no meaning in round-robin
2590 				 * mode. the window of a slave being up and
2591 				 * curr_active_slave being null after enslaving
2592 				 * is closed.
2593 				 */
2594 				if (!oldcurrent) {
2595 					printk(KERN_INFO DRV_NAME
2596 					       ": %s: link status definitely "
2597 					       "up for interface %s, ",
2598 					       bond_dev->name,
2599 					       slave->dev->name);
2600 					do_failover = 1;
2601 				} else {
2602 					printk(KERN_INFO DRV_NAME
2603 					       ": %s: interface %s is now up\n",
2604 					       bond_dev->name,
2605 					       slave->dev->name);
2606 				}
2607 			}
2608 		} else {
2609 			/* slave->link == BOND_LINK_UP */
2610 
2611 			/* not all switches will respond to an arp request
2612 			 * when the source ip is 0, so don't take the link down
2613 			 * if we don't know our ip yet
2614 			 */
2615 			if (((jiffies - slave->dev->trans_start) >= (2*delta_in_ticks)) ||
2616 			    (((jiffies - slave->dev->last_rx) >= (2*delta_in_ticks)) &&
2617 			     bond_has_ip(bond))) {
2618 
2619 				slave->link  = BOND_LINK_DOWN;
2620 				slave->state = BOND_STATE_BACKUP;
2621 
2622 				if (slave->link_failure_count < UINT_MAX) {
2623 					slave->link_failure_count++;
2624 				}
2625 
2626 				printk(KERN_INFO DRV_NAME
2627 				       ": %s: interface %s is now down.\n",
2628 				       bond_dev->name,
2629 				       slave->dev->name);
2630 
2631 				if (slave == oldcurrent) {
2632 					do_failover = 1;
2633 				}
2634 			}
2635 		}
2636 
2637 		/* note: if switch is in round-robin mode, all links
2638 		 * must tx arp to ensure all links rx an arp - otherwise
2639 		 * links may oscillate or not come up at all; if switch is
2640 		 * in something like xor mode, there is nothing we can
2641 		 * do - all replies will be rx'ed on same link causing slaves
2642 		 * to be unstable during low/no traffic periods
2643 		 */
2644 		if (IS_UP(slave->dev)) {
2645 			bond_arp_send_all(bond, slave);
2646 		}
2647 	}
2648 
2649 	if (do_failover) {
2650 		write_lock(&bond->curr_slave_lock);
2651 
2652 		bond_select_active_slave(bond);
2653 
2654 		write_unlock(&bond->curr_slave_lock);
2655 	}
2656 
2657 re_arm:
2658 	if (bond->params.arp_interval) {
2659 		mod_timer(&bond->arp_timer, jiffies + delta_in_ticks);
2660 	}
2661 out:
2662 	read_unlock(&bond->lock);
2663 }
2664 
2665 /*
2666  * When using arp monitoring in active-backup mode, this function is
2667  * called to determine if any backup slaves have went down or a new
2668  * current slave needs to be found.
2669  * The backup slaves never generate traffic, they are considered up by merely
2670  * receiving traffic. If the current slave goes down, each backup slave will
2671  * be given the opportunity to tx/rx an arp before being taken down - this
2672  * prevents all slaves from being taken down due to the current slave not
2673  * sending any traffic for the backups to receive. The arps are not necessarily
2674  * necessary, any tx and rx traffic will keep the current slave up. While any
2675  * rx traffic will keep the backup slaves up, the current slave is responsible
2676  * for generating traffic to keep them up regardless of any other traffic they
2677  * may have received.
2678  * see loadbalance_arp_monitor for arp monitoring in load balancing mode
2679  */
2680 void bond_activebackup_arp_mon(struct net_device *bond_dev)
2681 {
2682 	struct bonding *bond = bond_dev->priv;
2683 	struct slave *slave;
2684 	int delta_in_ticks;
2685 	int i;
2686 
2687 	read_lock(&bond->lock);
2688 
2689 	delta_in_ticks = (bond->params.arp_interval * HZ) / 1000;
2690 
2691 	if (bond->kill_timers) {
2692 		goto out;
2693 	}
2694 
2695 	if (bond->slave_cnt == 0) {
2696 		goto re_arm;
2697 	}
2698 
2699 	/* determine if any slave has come up or any backup slave has
2700 	 * gone down
2701 	 * TODO: what about up/down delay in arp mode? it wasn't here before
2702 	 *       so it can wait
2703 	 */
2704 	bond_for_each_slave(bond, slave, i) {
2705 		if (slave->link != BOND_LINK_UP) {
2706 			if ((jiffies - slave_last_rx(bond, slave)) <=
2707 			     delta_in_ticks) {
2708 
2709 				slave->link = BOND_LINK_UP;
2710 
2711 				write_lock(&bond->curr_slave_lock);
2712 
2713 				if ((!bond->curr_active_slave) &&
2714 				    ((jiffies - slave->dev->trans_start) <= delta_in_ticks)) {
2715 					bond_change_active_slave(bond, slave);
2716 					bond->current_arp_slave = NULL;
2717 				} else if (bond->curr_active_slave != slave) {
2718 					/* this slave has just come up but we
2719 					 * already have a current slave; this
2720 					 * can also happen if bond_enslave adds
2721 					 * a new slave that is up while we are
2722 					 * searching for a new slave
2723 					 */
2724 					bond_set_slave_inactive_flags(slave);
2725 					bond->current_arp_slave = NULL;
2726 				}
2727 
2728 				bond_set_carrier(bond);
2729 
2730 				if (slave == bond->curr_active_slave) {
2731 					printk(KERN_INFO DRV_NAME
2732 					       ": %s: %s is up and now the "
2733 					       "active interface\n",
2734 					       bond_dev->name,
2735 					       slave->dev->name);
2736 					netif_carrier_on(bond->dev);
2737 				} else {
2738 					printk(KERN_INFO DRV_NAME
2739 					       ": %s: backup interface %s is "
2740 					       "now up\n",
2741 					       bond_dev->name,
2742 					       slave->dev->name);
2743 				}
2744 
2745 				write_unlock(&bond->curr_slave_lock);
2746 			}
2747 		} else {
2748 			read_lock(&bond->curr_slave_lock);
2749 
2750 			if ((slave != bond->curr_active_slave) &&
2751 			    (!bond->current_arp_slave) &&
2752 			    (((jiffies - slave_last_rx(bond, slave)) >= 3*delta_in_ticks) &&
2753 			     bond_has_ip(bond))) {
2754 				/* a backup slave has gone down; three times
2755 				 * the delta allows the current slave to be
2756 				 * taken out before the backup slave.
2757 				 * note: a non-null current_arp_slave indicates
2758 				 * the curr_active_slave went down and we are
2759 				 * searching for a new one; under this
2760 				 * condition we only take the curr_active_slave
2761 				 * down - this gives each slave a chance to
2762 				 * tx/rx traffic before being taken out
2763 				 */
2764 
2765 				read_unlock(&bond->curr_slave_lock);
2766 
2767 				slave->link  = BOND_LINK_DOWN;
2768 
2769 				if (slave->link_failure_count < UINT_MAX) {
2770 					slave->link_failure_count++;
2771 				}
2772 
2773 				bond_set_slave_inactive_flags(slave);
2774 
2775 				printk(KERN_INFO DRV_NAME
2776 				       ": %s: backup interface %s is now down\n",
2777 				       bond_dev->name,
2778 				       slave->dev->name);
2779 			} else {
2780 				read_unlock(&bond->curr_slave_lock);
2781 			}
2782 		}
2783 	}
2784 
2785 	read_lock(&bond->curr_slave_lock);
2786 	slave = bond->curr_active_slave;
2787 	read_unlock(&bond->curr_slave_lock);
2788 
2789 	if (slave) {
2790 		/* if we have sent traffic in the past 2*arp_intervals but
2791 		 * haven't xmit and rx traffic in that time interval, select
2792 		 * a different slave. slave->jiffies is only updated when
2793 		 * a slave first becomes the curr_active_slave - not necessarily
2794 		 * after every arp; this ensures the slave has a full 2*delta
2795 		 * before being taken out. if a primary is being used, check
2796 		 * if it is up and needs to take over as the curr_active_slave
2797 		 */
2798 		if ((((jiffies - slave->dev->trans_start) >= (2*delta_in_ticks)) ||
2799 	    (((jiffies - slave_last_rx(bond, slave)) >= (2*delta_in_ticks)) &&
2800 	     bond_has_ip(bond))) &&
2801 		    ((jiffies - slave->jiffies) >= 2*delta_in_ticks)) {
2802 
2803 			slave->link  = BOND_LINK_DOWN;
2804 
2805 			if (slave->link_failure_count < UINT_MAX) {
2806 				slave->link_failure_count++;
2807 			}
2808 
2809 			printk(KERN_INFO DRV_NAME
2810 			       ": %s: link status down for active interface "
2811 			       "%s, disabling it\n",
2812 			       bond_dev->name,
2813 			       slave->dev->name);
2814 
2815 			write_lock(&bond->curr_slave_lock);
2816 
2817 			bond_select_active_slave(bond);
2818 			slave = bond->curr_active_slave;
2819 
2820 			write_unlock(&bond->curr_slave_lock);
2821 
2822 			bond->current_arp_slave = slave;
2823 
2824 			if (slave) {
2825 				slave->jiffies = jiffies;
2826 			}
2827 		} else if ((bond->primary_slave) &&
2828 			   (bond->primary_slave != slave) &&
2829 			   (bond->primary_slave->link == BOND_LINK_UP)) {
2830 			/* at this point, slave is the curr_active_slave */
2831 			printk(KERN_INFO DRV_NAME
2832 			       ": %s: changing from interface %s to primary "
2833 			       "interface %s\n",
2834 			       bond_dev->name,
2835 			       slave->dev->name,
2836 			       bond->primary_slave->dev->name);
2837 
2838 			/* primary is up so switch to it */
2839 			write_lock(&bond->curr_slave_lock);
2840 			bond_change_active_slave(bond, bond->primary_slave);
2841 			write_unlock(&bond->curr_slave_lock);
2842 
2843 			slave = bond->primary_slave;
2844 			slave->jiffies = jiffies;
2845 		} else {
2846 			bond->current_arp_slave = NULL;
2847 		}
2848 
2849 		/* the current slave must tx an arp to ensure backup slaves
2850 		 * rx traffic
2851 		 */
2852 		if (slave && bond_has_ip(bond)) {
2853 			bond_arp_send_all(bond, slave);
2854 		}
2855 	}
2856 
2857 	/* if we don't have a curr_active_slave, search for the next available
2858 	 * backup slave from the current_arp_slave and make it the candidate
2859 	 * for becoming the curr_active_slave
2860 	 */
2861 	if (!slave) {
2862 		if (!bond->current_arp_slave) {
2863 			bond->current_arp_slave = bond->first_slave;
2864 		}
2865 
2866 		if (bond->current_arp_slave) {
2867 			bond_set_slave_inactive_flags(bond->current_arp_slave);
2868 
2869 			/* search for next candidate */
2870 			bond_for_each_slave_from(bond, slave, i, bond->current_arp_slave->next) {
2871 				if (IS_UP(slave->dev)) {
2872 					slave->link = BOND_LINK_BACK;
2873 					bond_set_slave_active_flags(slave);
2874 					bond_arp_send_all(bond, slave);
2875 					slave->jiffies = jiffies;
2876 					bond->current_arp_slave = slave;
2877 					break;
2878 				}
2879 
2880 				/* if the link state is up at this point, we
2881 				 * mark it down - this can happen if we have
2882 				 * simultaneous link failures and
2883 				 * reselect_active_interface doesn't make this
2884 				 * one the current slave so it is still marked
2885 				 * up when it is actually down
2886 				 */
2887 				if (slave->link == BOND_LINK_UP) {
2888 					slave->link  = BOND_LINK_DOWN;
2889 					if (slave->link_failure_count < UINT_MAX) {
2890 						slave->link_failure_count++;
2891 					}
2892 
2893 					bond_set_slave_inactive_flags(slave);
2894 
2895 					printk(KERN_INFO DRV_NAME
2896 					       ": %s: backup interface %s is "
2897 					       "now down.\n",
2898 					       bond_dev->name,
2899 					       slave->dev->name);
2900 				}
2901 			}
2902 		}
2903 	}
2904 
2905 re_arm:
2906 	if (bond->params.arp_interval) {
2907 		mod_timer(&bond->arp_timer, jiffies + delta_in_ticks);
2908 	}
2909 out:
2910 	read_unlock(&bond->lock);
2911 }
2912 
2913 /*------------------------------ proc/seq_file-------------------------------*/
2914 
2915 #ifdef CONFIG_PROC_FS
2916 
2917 #define SEQ_START_TOKEN ((void *)1)
2918 
2919 static void *bond_info_seq_start(struct seq_file *seq, loff_t *pos)
2920 {
2921 	struct bonding *bond = seq->private;
2922 	loff_t off = 0;
2923 	struct slave *slave;
2924 	int i;
2925 
2926 	/* make sure the bond won't be taken away */
2927 	read_lock(&dev_base_lock);
2928 	read_lock_bh(&bond->lock);
2929 
2930 	if (*pos == 0) {
2931 		return SEQ_START_TOKEN;
2932 	}
2933 
2934 	bond_for_each_slave(bond, slave, i) {
2935 		if (++off == *pos) {
2936 			return slave;
2937 		}
2938 	}
2939 
2940 	return NULL;
2941 }
2942 
2943 static void *bond_info_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2944 {
2945 	struct bonding *bond = seq->private;
2946 	struct slave *slave = v;
2947 
2948 	++*pos;
2949 	if (v == SEQ_START_TOKEN) {
2950 		return bond->first_slave;
2951 	}
2952 
2953 	slave = slave->next;
2954 
2955 	return (slave == bond->first_slave) ? NULL : slave;
2956 }
2957 
2958 static void bond_info_seq_stop(struct seq_file *seq, void *v)
2959 {
2960 	struct bonding *bond = seq->private;
2961 
2962 	read_unlock_bh(&bond->lock);
2963 	read_unlock(&dev_base_lock);
2964 }
2965 
2966 static void bond_info_show_master(struct seq_file *seq)
2967 {
2968 	struct bonding *bond = seq->private;
2969 	struct slave *curr;
2970 	int i;
2971 	u32 target;
2972 
2973 	read_lock(&bond->curr_slave_lock);
2974 	curr = bond->curr_active_slave;
2975 	read_unlock(&bond->curr_slave_lock);
2976 
2977 	seq_printf(seq, "Bonding Mode: %s\n",
2978 		   bond_mode_name(bond->params.mode));
2979 
2980 	if (bond->params.mode == BOND_MODE_XOR ||
2981 		bond->params.mode == BOND_MODE_8023AD) {
2982 		seq_printf(seq, "Transmit Hash Policy: %s (%d)\n",
2983 			xmit_hashtype_tbl[bond->params.xmit_policy].modename,
2984 			bond->params.xmit_policy);
2985 	}
2986 
2987 	if (USES_PRIMARY(bond->params.mode)) {
2988 		seq_printf(seq, "Primary Slave: %s\n",
2989 			   (bond->primary_slave) ?
2990 			   bond->primary_slave->dev->name : "None");
2991 
2992 		seq_printf(seq, "Currently Active Slave: %s\n",
2993 			   (curr) ? curr->dev->name : "None");
2994 	}
2995 
2996 	seq_printf(seq, "MII Status: %s\n", netif_carrier_ok(bond->dev) ?
2997 		   "up" : "down");
2998 	seq_printf(seq, "MII Polling Interval (ms): %d\n", bond->params.miimon);
2999 	seq_printf(seq, "Up Delay (ms): %d\n",
3000 		   bond->params.updelay * bond->params.miimon);
3001 	seq_printf(seq, "Down Delay (ms): %d\n",
3002 		   bond->params.downdelay * bond->params.miimon);
3003 
3004 
3005 	/* ARP information */
3006 	if(bond->params.arp_interval > 0) {
3007 		int printed=0;
3008 		seq_printf(seq, "ARP Polling Interval (ms): %d\n",
3009 				bond->params.arp_interval);
3010 
3011 		seq_printf(seq, "ARP IP target/s (n.n.n.n form):");
3012 
3013 		for(i = 0; (i < BOND_MAX_ARP_TARGETS) ;i++) {
3014 			if (!bond->params.arp_targets[i])
3015 				continue;
3016 			if (printed)
3017 				seq_printf(seq, ",");
3018 			target = ntohl(bond->params.arp_targets[i]);
3019 			seq_printf(seq, " %d.%d.%d.%d", HIPQUAD(target));
3020 			printed = 1;
3021 		}
3022 		seq_printf(seq, "\n");
3023 	}
3024 
3025 	if (bond->params.mode == BOND_MODE_8023AD) {
3026 		struct ad_info ad_info;
3027 
3028 		seq_puts(seq, "\n802.3ad info\n");
3029 		seq_printf(seq, "LACP rate: %s\n",
3030 			   (bond->params.lacp_fast) ? "fast" : "slow");
3031 
3032 		if (bond_3ad_get_active_agg_info(bond, &ad_info)) {
3033 			seq_printf(seq, "bond %s has no active aggregator\n",
3034 				   bond->dev->name);
3035 		} else {
3036 			seq_printf(seq, "Active Aggregator Info:\n");
3037 
3038 			seq_printf(seq, "\tAggregator ID: %d\n",
3039 				   ad_info.aggregator_id);
3040 			seq_printf(seq, "\tNumber of ports: %d\n",
3041 				   ad_info.ports);
3042 			seq_printf(seq, "\tActor Key: %d\n",
3043 				   ad_info.actor_key);
3044 			seq_printf(seq, "\tPartner Key: %d\n",
3045 				   ad_info.partner_key);
3046 			seq_printf(seq, "\tPartner Mac Address: %02x:%02x:%02x:%02x:%02x:%02x\n",
3047 				   ad_info.partner_system[0],
3048 				   ad_info.partner_system[1],
3049 				   ad_info.partner_system[2],
3050 				   ad_info.partner_system[3],
3051 				   ad_info.partner_system[4],
3052 				   ad_info.partner_system[5]);
3053 		}
3054 	}
3055 }
3056 
3057 static void bond_info_show_slave(struct seq_file *seq, const struct slave *slave)
3058 {
3059 	struct bonding *bond = seq->private;
3060 
3061 	seq_printf(seq, "\nSlave Interface: %s\n", slave->dev->name);
3062 	seq_printf(seq, "MII Status: %s\n",
3063 		   (slave->link == BOND_LINK_UP) ?  "up" : "down");
3064 	seq_printf(seq, "Link Failure Count: %u\n",
3065 		   slave->link_failure_count);
3066 
3067 	seq_printf(seq,
3068 		   "Permanent HW addr: %02x:%02x:%02x:%02x:%02x:%02x\n",
3069 		   slave->perm_hwaddr[0], slave->perm_hwaddr[1],
3070 		   slave->perm_hwaddr[2], slave->perm_hwaddr[3],
3071 		   slave->perm_hwaddr[4], slave->perm_hwaddr[5]);
3072 
3073 	if (bond->params.mode == BOND_MODE_8023AD) {
3074 		const struct aggregator *agg
3075 			= SLAVE_AD_INFO(slave).port.aggregator;
3076 
3077 		if (agg) {
3078 			seq_printf(seq, "Aggregator ID: %d\n",
3079 				   agg->aggregator_identifier);
3080 		} else {
3081 			seq_puts(seq, "Aggregator ID: N/A\n");
3082 		}
3083 	}
3084 }
3085 
3086 static int bond_info_seq_show(struct seq_file *seq, void *v)
3087 {
3088 	if (v == SEQ_START_TOKEN) {
3089 		seq_printf(seq, "%s\n", version);
3090 		bond_info_show_master(seq);
3091 	} else {
3092 		bond_info_show_slave(seq, v);
3093 	}
3094 
3095 	return 0;
3096 }
3097 
3098 static struct seq_operations bond_info_seq_ops = {
3099 	.start = bond_info_seq_start,
3100 	.next  = bond_info_seq_next,
3101 	.stop  = bond_info_seq_stop,
3102 	.show  = bond_info_seq_show,
3103 };
3104 
3105 static int bond_info_open(struct inode *inode, struct file *file)
3106 {
3107 	struct seq_file *seq;
3108 	struct proc_dir_entry *proc;
3109 	int res;
3110 
3111 	res = seq_open(file, &bond_info_seq_ops);
3112 	if (!res) {
3113 		/* recover the pointer buried in proc_dir_entry data */
3114 		seq = file->private_data;
3115 		proc = PDE(inode);
3116 		seq->private = proc->data;
3117 	}
3118 
3119 	return res;
3120 }
3121 
3122 static const struct file_operations bond_info_fops = {
3123 	.owner   = THIS_MODULE,
3124 	.open    = bond_info_open,
3125 	.read    = seq_read,
3126 	.llseek  = seq_lseek,
3127 	.release = seq_release,
3128 };
3129 
3130 static int bond_create_proc_entry(struct bonding *bond)
3131 {
3132 	struct net_device *bond_dev = bond->dev;
3133 
3134 	if (bond_proc_dir) {
3135 		bond->proc_entry = create_proc_entry(bond_dev->name,
3136 						     S_IRUGO,
3137 						     bond_proc_dir);
3138 		if (bond->proc_entry == NULL) {
3139 			printk(KERN_WARNING DRV_NAME
3140 			       ": Warning: Cannot create /proc/net/%s/%s\n",
3141 			       DRV_NAME, bond_dev->name);
3142 		} else {
3143 			bond->proc_entry->data = bond;
3144 			bond->proc_entry->proc_fops = &bond_info_fops;
3145 			bond->proc_entry->owner = THIS_MODULE;
3146 			memcpy(bond->proc_file_name, bond_dev->name, IFNAMSIZ);
3147 		}
3148 	}
3149 
3150 	return 0;
3151 }
3152 
3153 static void bond_remove_proc_entry(struct bonding *bond)
3154 {
3155 	if (bond_proc_dir && bond->proc_entry) {
3156 		remove_proc_entry(bond->proc_file_name, bond_proc_dir);
3157 		memset(bond->proc_file_name, 0, IFNAMSIZ);
3158 		bond->proc_entry = NULL;
3159 	}
3160 }
3161 
3162 /* Create the bonding directory under /proc/net, if doesn't exist yet.
3163  * Caller must hold rtnl_lock.
3164  */
3165 static void bond_create_proc_dir(void)
3166 {
3167 	int len = strlen(DRV_NAME);
3168 
3169 	for (bond_proc_dir = proc_net->subdir; bond_proc_dir;
3170 	     bond_proc_dir = bond_proc_dir->next) {
3171 		if ((bond_proc_dir->namelen == len) &&
3172 		    !memcmp(bond_proc_dir->name, DRV_NAME, len)) {
3173 			break;
3174 		}
3175 	}
3176 
3177 	if (!bond_proc_dir) {
3178 		bond_proc_dir = proc_mkdir(DRV_NAME, proc_net);
3179 		if (bond_proc_dir) {
3180 			bond_proc_dir->owner = THIS_MODULE;
3181 		} else {
3182 			printk(KERN_WARNING DRV_NAME
3183 				": Warning: cannot create /proc/net/%s\n",
3184 				DRV_NAME);
3185 		}
3186 	}
3187 }
3188 
3189 /* Destroy the bonding directory under /proc/net, if empty.
3190  * Caller must hold rtnl_lock.
3191  */
3192 static void bond_destroy_proc_dir(void)
3193 {
3194 	struct proc_dir_entry *de;
3195 
3196 	if (!bond_proc_dir) {
3197 		return;
3198 	}
3199 
3200 	/* verify that the /proc dir is empty */
3201 	for (de = bond_proc_dir->subdir; de; de = de->next) {
3202 		/* ignore . and .. */
3203 		if (*(de->name) != '.') {
3204 			break;
3205 		}
3206 	}
3207 
3208 	if (de) {
3209 		if (bond_proc_dir->owner == THIS_MODULE) {
3210 			bond_proc_dir->owner = NULL;
3211 		}
3212 	} else {
3213 		remove_proc_entry(DRV_NAME, proc_net);
3214 		bond_proc_dir = NULL;
3215 	}
3216 }
3217 #endif /* CONFIG_PROC_FS */
3218 
3219 /*-------------------------- netdev event handling --------------------------*/
3220 
3221 /*
3222  * Change device name
3223  */
3224 static int bond_event_changename(struct bonding *bond)
3225 {
3226 #ifdef CONFIG_PROC_FS
3227 	bond_remove_proc_entry(bond);
3228 	bond_create_proc_entry(bond);
3229 #endif
3230 	down_write(&(bonding_rwsem));
3231         bond_destroy_sysfs_entry(bond);
3232         bond_create_sysfs_entry(bond);
3233 	up_write(&(bonding_rwsem));
3234 	return NOTIFY_DONE;
3235 }
3236 
3237 static int bond_master_netdev_event(unsigned long event, struct net_device *bond_dev)
3238 {
3239 	struct bonding *event_bond = bond_dev->priv;
3240 
3241 	switch (event) {
3242 	case NETDEV_CHANGENAME:
3243 		return bond_event_changename(event_bond);
3244 	case NETDEV_UNREGISTER:
3245 		/*
3246 		 * TODO: remove a bond from the list?
3247 		 */
3248 		break;
3249 	default:
3250 		break;
3251 	}
3252 
3253 	return NOTIFY_DONE;
3254 }
3255 
3256 static int bond_slave_netdev_event(unsigned long event, struct net_device *slave_dev)
3257 {
3258 	struct net_device *bond_dev = slave_dev->master;
3259 	struct bonding *bond = bond_dev->priv;
3260 
3261 	switch (event) {
3262 	case NETDEV_UNREGISTER:
3263 		if (bond_dev) {
3264 			bond_release(bond_dev, slave_dev);
3265 		}
3266 		break;
3267 	case NETDEV_CHANGE:
3268 		/*
3269 		 * TODO: is this what we get if somebody
3270 		 * sets up a hierarchical bond, then rmmod's
3271 		 * one of the slave bonding devices?
3272 		 */
3273 		break;
3274 	case NETDEV_DOWN:
3275 		/*
3276 		 * ... Or is it this?
3277 		 */
3278 		break;
3279 	case NETDEV_CHANGEMTU:
3280 		/*
3281 		 * TODO: Should slaves be allowed to
3282 		 * independently alter their MTU?  For
3283 		 * an active-backup bond, slaves need
3284 		 * not be the same type of device, so
3285 		 * MTUs may vary.  For other modes,
3286 		 * slaves arguably should have the
3287 		 * same MTUs. To do this, we'd need to
3288 		 * take over the slave's change_mtu
3289 		 * function for the duration of their
3290 		 * servitude.
3291 		 */
3292 		break;
3293 	case NETDEV_CHANGENAME:
3294 		/*
3295 		 * TODO: handle changing the primary's name
3296 		 */
3297 		break;
3298 	case NETDEV_FEAT_CHANGE:
3299 		bond_compute_features(bond);
3300 		break;
3301 	default:
3302 		break;
3303 	}
3304 
3305 	return NOTIFY_DONE;
3306 }
3307 
3308 /*
3309  * bond_netdev_event: handle netdev notifier chain events.
3310  *
3311  * This function receives events for the netdev chain.  The caller (an
3312  * ioctl handler calling blocking_notifier_call_chain) holds the necessary
3313  * locks for us to safely manipulate the slave devices (RTNL lock,
3314  * dev_probe_lock).
3315  */
3316 static int bond_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
3317 {
3318 	struct net_device *event_dev = (struct net_device *)ptr;
3319 
3320 	dprintk("event_dev: %s, event: %lx\n",
3321 		(event_dev ? event_dev->name : "None"),
3322 		event);
3323 
3324 	if (!(event_dev->priv_flags & IFF_BONDING))
3325 		return NOTIFY_DONE;
3326 
3327 	if (event_dev->flags & IFF_MASTER) {
3328 		dprintk("IFF_MASTER\n");
3329 		return bond_master_netdev_event(event, event_dev);
3330 	}
3331 
3332 	if (event_dev->flags & IFF_SLAVE) {
3333 		dprintk("IFF_SLAVE\n");
3334 		return bond_slave_netdev_event(event, event_dev);
3335 	}
3336 
3337 	return NOTIFY_DONE;
3338 }
3339 
3340 /*
3341  * bond_inetaddr_event: handle inetaddr notifier chain events.
3342  *
3343  * We keep track of device IPs primarily to use as source addresses in
3344  * ARP monitor probes (rather than spewing out broadcasts all the time).
3345  *
3346  * We track one IP for the main device (if it has one), plus one per VLAN.
3347  */
3348 static int bond_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
3349 {
3350 	struct in_ifaddr *ifa = ptr;
3351 	struct net_device *vlan_dev, *event_dev = ifa->ifa_dev->dev;
3352 	struct bonding *bond, *bond_next;
3353 	struct vlan_entry *vlan, *vlan_next;
3354 
3355 	list_for_each_entry_safe(bond, bond_next, &bond_dev_list, bond_list) {
3356 		if (bond->dev == event_dev) {
3357 			switch (event) {
3358 			case NETDEV_UP:
3359 				bond->master_ip = ifa->ifa_local;
3360 				return NOTIFY_OK;
3361 			case NETDEV_DOWN:
3362 				bond->master_ip = bond_glean_dev_ip(bond->dev);
3363 				return NOTIFY_OK;
3364 			default:
3365 				return NOTIFY_DONE;
3366 			}
3367 		}
3368 
3369 		if (list_empty(&bond->vlan_list))
3370 			continue;
3371 
3372 		list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
3373 					 vlan_list) {
3374 			vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
3375 			if (vlan_dev == event_dev) {
3376 				switch (event) {
3377 				case NETDEV_UP:
3378 					vlan->vlan_ip = ifa->ifa_local;
3379 					return NOTIFY_OK;
3380 				case NETDEV_DOWN:
3381 					vlan->vlan_ip =
3382 						bond_glean_dev_ip(vlan_dev);
3383 					return NOTIFY_OK;
3384 				default:
3385 					return NOTIFY_DONE;
3386 				}
3387 			}
3388 		}
3389 	}
3390 	return NOTIFY_DONE;
3391 }
3392 
3393 static struct notifier_block bond_netdev_notifier = {
3394 	.notifier_call = bond_netdev_event,
3395 };
3396 
3397 static struct notifier_block bond_inetaddr_notifier = {
3398 	.notifier_call = bond_inetaddr_event,
3399 };
3400 
3401 /*-------------------------- Packet type handling ---------------------------*/
3402 
3403 /* register to receive lacpdus on a bond */
3404 static void bond_register_lacpdu(struct bonding *bond)
3405 {
3406 	struct packet_type *pk_type = &(BOND_AD_INFO(bond).ad_pkt_type);
3407 
3408 	/* initialize packet type */
3409 	pk_type->type = PKT_TYPE_LACPDU;
3410 	pk_type->dev = bond->dev;
3411 	pk_type->func = bond_3ad_lacpdu_recv;
3412 
3413 	dev_add_pack(pk_type);
3414 }
3415 
3416 /* unregister to receive lacpdus on a bond */
3417 static void bond_unregister_lacpdu(struct bonding *bond)
3418 {
3419 	dev_remove_pack(&(BOND_AD_INFO(bond).ad_pkt_type));
3420 }
3421 
3422 void bond_register_arp(struct bonding *bond)
3423 {
3424 	struct packet_type *pt = &bond->arp_mon_pt;
3425 
3426 	pt->type = htons(ETH_P_ARP);
3427 	pt->dev = NULL; /*bond->dev;XXX*/
3428 	pt->func = bond_arp_rcv;
3429 	dev_add_pack(pt);
3430 }
3431 
3432 void bond_unregister_arp(struct bonding *bond)
3433 {
3434 	dev_remove_pack(&bond->arp_mon_pt);
3435 }
3436 
3437 /*---------------------------- Hashing Policies -----------------------------*/
3438 
3439 /*
3440  * Hash for the the output device based upon layer 3 and layer 4 data. If
3441  * the packet is a frag or not TCP or UDP, just use layer 3 data.  If it is
3442  * altogether not IP, mimic bond_xmit_hash_policy_l2()
3443  */
3444 static int bond_xmit_hash_policy_l34(struct sk_buff *skb,
3445 				    struct net_device *bond_dev, int count)
3446 {
3447 	struct ethhdr *data = (struct ethhdr *)skb->data;
3448 	struct iphdr *iph = skb->nh.iph;
3449 	u16 *layer4hdr = (u16 *)((u32 *)iph + iph->ihl);
3450 	int layer4_xor = 0;
3451 
3452 	if (skb->protocol == __constant_htons(ETH_P_IP)) {
3453 		if (!(iph->frag_off & __constant_htons(IP_MF|IP_OFFSET)) &&
3454 		    (iph->protocol == IPPROTO_TCP ||
3455 		     iph->protocol == IPPROTO_UDP)) {
3456 			layer4_xor = htons((*layer4hdr ^ *(layer4hdr + 1)));
3457 		}
3458 		return (layer4_xor ^
3459 			((ntohl(iph->saddr ^ iph->daddr)) & 0xffff)) % count;
3460 
3461 	}
3462 
3463 	return (data->h_dest[5] ^ bond_dev->dev_addr[5]) % count;
3464 }
3465 
3466 /*
3467  * Hash for the output device based upon layer 2 data
3468  */
3469 static int bond_xmit_hash_policy_l2(struct sk_buff *skb,
3470 				   struct net_device *bond_dev, int count)
3471 {
3472 	struct ethhdr *data = (struct ethhdr *)skb->data;
3473 
3474 	return (data->h_dest[5] ^ bond_dev->dev_addr[5]) % count;
3475 }
3476 
3477 /*-------------------------- Device entry points ----------------------------*/
3478 
3479 static int bond_open(struct net_device *bond_dev)
3480 {
3481 	struct bonding *bond = bond_dev->priv;
3482 	struct timer_list *mii_timer = &bond->mii_timer;
3483 	struct timer_list *arp_timer = &bond->arp_timer;
3484 
3485 	bond->kill_timers = 0;
3486 
3487 	if ((bond->params.mode == BOND_MODE_TLB) ||
3488 	    (bond->params.mode == BOND_MODE_ALB)) {
3489 		struct timer_list *alb_timer = &(BOND_ALB_INFO(bond).alb_timer);
3490 
3491 		/* bond_alb_initialize must be called before the timer
3492 		 * is started.
3493 		 */
3494 		if (bond_alb_initialize(bond, (bond->params.mode == BOND_MODE_ALB))) {
3495 			/* something went wrong - fail the open operation */
3496 			return -1;
3497 		}
3498 
3499 		init_timer(alb_timer);
3500 		alb_timer->expires  = jiffies + 1;
3501 		alb_timer->data     = (unsigned long)bond;
3502 		alb_timer->function = (void *)&bond_alb_monitor;
3503 		add_timer(alb_timer);
3504 	}
3505 
3506 	if (bond->params.miimon) {  /* link check interval, in milliseconds. */
3507 		init_timer(mii_timer);
3508 		mii_timer->expires  = jiffies + 1;
3509 		mii_timer->data     = (unsigned long)bond_dev;
3510 		mii_timer->function = (void *)&bond_mii_monitor;
3511 		add_timer(mii_timer);
3512 	}
3513 
3514 	if (bond->params.arp_interval) {  /* arp interval, in milliseconds. */
3515 		init_timer(arp_timer);
3516 		arp_timer->expires  = jiffies + 1;
3517 		arp_timer->data     = (unsigned long)bond_dev;
3518 		if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
3519 			arp_timer->function = (void *)&bond_activebackup_arp_mon;
3520 		} else {
3521 			arp_timer->function = (void *)&bond_loadbalance_arp_mon;
3522 		}
3523 		if (bond->params.arp_validate)
3524 			bond_register_arp(bond);
3525 
3526 		add_timer(arp_timer);
3527 	}
3528 
3529 	if (bond->params.mode == BOND_MODE_8023AD) {
3530 		struct timer_list *ad_timer = &(BOND_AD_INFO(bond).ad_timer);
3531 		init_timer(ad_timer);
3532 		ad_timer->expires  = jiffies + 1;
3533 		ad_timer->data     = (unsigned long)bond;
3534 		ad_timer->function = (void *)&bond_3ad_state_machine_handler;
3535 		add_timer(ad_timer);
3536 
3537 		/* register to receive LACPDUs */
3538 		bond_register_lacpdu(bond);
3539 	}
3540 
3541 	return 0;
3542 }
3543 
3544 static int bond_close(struct net_device *bond_dev)
3545 {
3546 	struct bonding *bond = bond_dev->priv;
3547 
3548 	if (bond->params.mode == BOND_MODE_8023AD) {
3549 		/* Unregister the receive of LACPDUs */
3550 		bond_unregister_lacpdu(bond);
3551 	}
3552 
3553 	if (bond->params.arp_validate)
3554 		bond_unregister_arp(bond);
3555 
3556 	write_lock_bh(&bond->lock);
3557 
3558 
3559 	/* signal timers not to re-arm */
3560 	bond->kill_timers = 1;
3561 
3562 	write_unlock_bh(&bond->lock);
3563 
3564 	/* del_timer_sync must run without holding the bond->lock
3565 	 * because a running timer might be trying to hold it too
3566 	 */
3567 
3568 	if (bond->params.miimon) {  /* link check interval, in milliseconds. */
3569 		del_timer_sync(&bond->mii_timer);
3570 	}
3571 
3572 	if (bond->params.arp_interval) {  /* arp interval, in milliseconds. */
3573 		del_timer_sync(&bond->arp_timer);
3574 	}
3575 
3576 	switch (bond->params.mode) {
3577 	case BOND_MODE_8023AD:
3578 		del_timer_sync(&(BOND_AD_INFO(bond).ad_timer));
3579 		break;
3580 	case BOND_MODE_TLB:
3581 	case BOND_MODE_ALB:
3582 		del_timer_sync(&(BOND_ALB_INFO(bond).alb_timer));
3583 		break;
3584 	default:
3585 		break;
3586 	}
3587 
3588 
3589 	if ((bond->params.mode == BOND_MODE_TLB) ||
3590 	    (bond->params.mode == BOND_MODE_ALB)) {
3591 		/* Must be called only after all
3592 		 * slaves have been released
3593 		 */
3594 		bond_alb_deinitialize(bond);
3595 	}
3596 
3597 	return 0;
3598 }
3599 
3600 static struct net_device_stats *bond_get_stats(struct net_device *bond_dev)
3601 {
3602 	struct bonding *bond = bond_dev->priv;
3603 	struct net_device_stats *stats = &(bond->stats), *sstats;
3604 	struct slave *slave;
3605 	int i;
3606 
3607 	memset(stats, 0, sizeof(struct net_device_stats));
3608 
3609 	read_lock_bh(&bond->lock);
3610 
3611 	bond_for_each_slave(bond, slave, i) {
3612 		if (slave->dev->get_stats) {
3613 			sstats = slave->dev->get_stats(slave->dev);
3614 
3615 			stats->rx_packets += sstats->rx_packets;
3616 			stats->rx_bytes += sstats->rx_bytes;
3617 			stats->rx_errors += sstats->rx_errors;
3618 			stats->rx_dropped += sstats->rx_dropped;
3619 
3620 			stats->tx_packets += sstats->tx_packets;
3621 			stats->tx_bytes += sstats->tx_bytes;
3622 			stats->tx_errors += sstats->tx_errors;
3623 			stats->tx_dropped += sstats->tx_dropped;
3624 
3625 			stats->multicast += sstats->multicast;
3626 			stats->collisions += sstats->collisions;
3627 
3628 			stats->rx_length_errors += sstats->rx_length_errors;
3629 			stats->rx_over_errors += sstats->rx_over_errors;
3630 			stats->rx_crc_errors += sstats->rx_crc_errors;
3631 			stats->rx_frame_errors += sstats->rx_frame_errors;
3632 			stats->rx_fifo_errors += sstats->rx_fifo_errors;
3633 			stats->rx_missed_errors += sstats->rx_missed_errors;
3634 
3635 			stats->tx_aborted_errors += sstats->tx_aborted_errors;
3636 			stats->tx_carrier_errors += sstats->tx_carrier_errors;
3637 			stats->tx_fifo_errors += sstats->tx_fifo_errors;
3638 			stats->tx_heartbeat_errors += sstats->tx_heartbeat_errors;
3639 			stats->tx_window_errors += sstats->tx_window_errors;
3640 		}
3641 	}
3642 
3643 	read_unlock_bh(&bond->lock);
3644 
3645 	return stats;
3646 }
3647 
3648 static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd)
3649 {
3650 	struct net_device *slave_dev = NULL;
3651 	struct ifbond k_binfo;
3652 	struct ifbond __user *u_binfo = NULL;
3653 	struct ifslave k_sinfo;
3654 	struct ifslave __user *u_sinfo = NULL;
3655 	struct mii_ioctl_data *mii = NULL;
3656 	int res = 0;
3657 
3658 	dprintk("bond_ioctl: master=%s, cmd=%d\n",
3659 		bond_dev->name, cmd);
3660 
3661 	switch (cmd) {
3662 	case SIOCGMIIPHY:
3663 		mii = if_mii(ifr);
3664 		if (!mii) {
3665 			return -EINVAL;
3666 		}
3667 		mii->phy_id = 0;
3668 		/* Fall Through */
3669 	case SIOCGMIIREG:
3670 		/*
3671 		 * We do this again just in case we were called by SIOCGMIIREG
3672 		 * instead of SIOCGMIIPHY.
3673 		 */
3674 		mii = if_mii(ifr);
3675 		if (!mii) {
3676 			return -EINVAL;
3677 		}
3678 
3679 		if (mii->reg_num == 1) {
3680 			struct bonding *bond = bond_dev->priv;
3681 			mii->val_out = 0;
3682 			read_lock_bh(&bond->lock);
3683 			read_lock(&bond->curr_slave_lock);
3684 			if (netif_carrier_ok(bond->dev)) {
3685 				mii->val_out = BMSR_LSTATUS;
3686 			}
3687 			read_unlock(&bond->curr_slave_lock);
3688 			read_unlock_bh(&bond->lock);
3689 		}
3690 
3691 		return 0;
3692 	case BOND_INFO_QUERY_OLD:
3693 	case SIOCBONDINFOQUERY:
3694 		u_binfo = (struct ifbond __user *)ifr->ifr_data;
3695 
3696 		if (copy_from_user(&k_binfo, u_binfo, sizeof(ifbond))) {
3697 			return -EFAULT;
3698 		}
3699 
3700 		res = bond_info_query(bond_dev, &k_binfo);
3701 		if (res == 0) {
3702 			if (copy_to_user(u_binfo, &k_binfo, sizeof(ifbond))) {
3703 				return -EFAULT;
3704 			}
3705 		}
3706 
3707 		return res;
3708 	case BOND_SLAVE_INFO_QUERY_OLD:
3709 	case SIOCBONDSLAVEINFOQUERY:
3710 		u_sinfo = (struct ifslave __user *)ifr->ifr_data;
3711 
3712 		if (copy_from_user(&k_sinfo, u_sinfo, sizeof(ifslave))) {
3713 			return -EFAULT;
3714 		}
3715 
3716 		res = bond_slave_info_query(bond_dev, &k_sinfo);
3717 		if (res == 0) {
3718 			if (copy_to_user(u_sinfo, &k_sinfo, sizeof(ifslave))) {
3719 				return -EFAULT;
3720 			}
3721 		}
3722 
3723 		return res;
3724 	default:
3725 		/* Go on */
3726 		break;
3727 	}
3728 
3729 	if (!capable(CAP_NET_ADMIN)) {
3730 		return -EPERM;
3731 	}
3732 
3733 	down_write(&(bonding_rwsem));
3734 	slave_dev = dev_get_by_name(ifr->ifr_slave);
3735 
3736 	dprintk("slave_dev=%p: \n", slave_dev);
3737 
3738 	if (!slave_dev) {
3739 		res = -ENODEV;
3740 	} else {
3741 		dprintk("slave_dev->name=%s: \n", slave_dev->name);
3742 		switch (cmd) {
3743 		case BOND_ENSLAVE_OLD:
3744 		case SIOCBONDENSLAVE:
3745 			res = bond_enslave(bond_dev, slave_dev);
3746 			break;
3747 		case BOND_RELEASE_OLD:
3748 		case SIOCBONDRELEASE:
3749 			res = bond_release(bond_dev, slave_dev);
3750 			break;
3751 		case BOND_SETHWADDR_OLD:
3752 		case SIOCBONDSETHWADDR:
3753 			res = bond_sethwaddr(bond_dev, slave_dev);
3754 			break;
3755 		case BOND_CHANGE_ACTIVE_OLD:
3756 		case SIOCBONDCHANGEACTIVE:
3757 			res = bond_ioctl_change_active(bond_dev, slave_dev);
3758 			break;
3759 		default:
3760 			res = -EOPNOTSUPP;
3761 		}
3762 
3763 		dev_put(slave_dev);
3764 	}
3765 
3766 	up_write(&(bonding_rwsem));
3767 	return res;
3768 }
3769 
3770 static void bond_set_multicast_list(struct net_device *bond_dev)
3771 {
3772 	struct bonding *bond = bond_dev->priv;
3773 	struct dev_mc_list *dmi;
3774 
3775 	write_lock_bh(&bond->lock);
3776 
3777 	/*
3778 	 * Do promisc before checking multicast_mode
3779 	 */
3780 	if ((bond_dev->flags & IFF_PROMISC) && !(bond->flags & IFF_PROMISC)) {
3781 		bond_set_promiscuity(bond, 1);
3782 	}
3783 
3784 	if (!(bond_dev->flags & IFF_PROMISC) && (bond->flags & IFF_PROMISC)) {
3785 		bond_set_promiscuity(bond, -1);
3786 	}
3787 
3788 	/* set allmulti flag to slaves */
3789 	if ((bond_dev->flags & IFF_ALLMULTI) && !(bond->flags & IFF_ALLMULTI)) {
3790 		bond_set_allmulti(bond, 1);
3791 	}
3792 
3793 	if (!(bond_dev->flags & IFF_ALLMULTI) && (bond->flags & IFF_ALLMULTI)) {
3794 		bond_set_allmulti(bond, -1);
3795 	}
3796 
3797 	bond->flags = bond_dev->flags;
3798 
3799 	/* looking for addresses to add to slaves' mc list */
3800 	for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
3801 		if (!bond_mc_list_find_dmi(dmi, bond->mc_list)) {
3802 			bond_mc_add(bond, dmi->dmi_addr, dmi->dmi_addrlen);
3803 		}
3804 	}
3805 
3806 	/* looking for addresses to delete from slaves' list */
3807 	for (dmi = bond->mc_list; dmi; dmi = dmi->next) {
3808 		if (!bond_mc_list_find_dmi(dmi, bond_dev->mc_list)) {
3809 			bond_mc_delete(bond, dmi->dmi_addr, dmi->dmi_addrlen);
3810 		}
3811 	}
3812 
3813 	/* save master's multicast list */
3814 	bond_mc_list_destroy(bond);
3815 	bond_mc_list_copy(bond_dev->mc_list, bond, GFP_ATOMIC);
3816 
3817 	write_unlock_bh(&bond->lock);
3818 }
3819 
3820 /*
3821  * Change the MTU of all of a master's slaves to match the master
3822  */
3823 static int bond_change_mtu(struct net_device *bond_dev, int new_mtu)
3824 {
3825 	struct bonding *bond = bond_dev->priv;
3826 	struct slave *slave, *stop_at;
3827 	int res = 0;
3828 	int i;
3829 
3830 	dprintk("bond=%p, name=%s, new_mtu=%d\n", bond,
3831 		(bond_dev ? bond_dev->name : "None"), new_mtu);
3832 
3833 	/* Can't hold bond->lock with bh disabled here since
3834 	 * some base drivers panic. On the other hand we can't
3835 	 * hold bond->lock without bh disabled because we'll
3836 	 * deadlock. The only solution is to rely on the fact
3837 	 * that we're under rtnl_lock here, and the slaves
3838 	 * list won't change. This doesn't solve the problem
3839 	 * of setting the slave's MTU while it is
3840 	 * transmitting, but the assumption is that the base
3841 	 * driver can handle that.
3842 	 *
3843 	 * TODO: figure out a way to safely iterate the slaves
3844 	 * list, but without holding a lock around the actual
3845 	 * call to the base driver.
3846 	 */
3847 
3848 	bond_for_each_slave(bond, slave, i) {
3849 		dprintk("s %p s->p %p c_m %p\n", slave,
3850 			slave->prev, slave->dev->change_mtu);
3851 
3852 		res = dev_set_mtu(slave->dev, new_mtu);
3853 
3854 		if (res) {
3855 			/* If we failed to set the slave's mtu to the new value
3856 			 * we must abort the operation even in ACTIVE_BACKUP
3857 			 * mode, because if we allow the backup slaves to have
3858 			 * different mtu values than the active slave we'll
3859 			 * need to change their mtu when doing a failover. That
3860 			 * means changing their mtu from timer context, which
3861 			 * is probably not a good idea.
3862 			 */
3863 			dprintk("err %d %s\n", res, slave->dev->name);
3864 			goto unwind;
3865 		}
3866 	}
3867 
3868 	bond_dev->mtu = new_mtu;
3869 
3870 	return 0;
3871 
3872 unwind:
3873 	/* unwind from head to the slave that failed */
3874 	stop_at = slave;
3875 	bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
3876 		int tmp_res;
3877 
3878 		tmp_res = dev_set_mtu(slave->dev, bond_dev->mtu);
3879 		if (tmp_res) {
3880 			dprintk("unwind err %d dev %s\n", tmp_res,
3881 				slave->dev->name);
3882 		}
3883 	}
3884 
3885 	return res;
3886 }
3887 
3888 /*
3889  * Change HW address
3890  *
3891  * Note that many devices must be down to change the HW address, and
3892  * downing the master releases all slaves.  We can make bonds full of
3893  * bonding devices to test this, however.
3894  */
3895 static int bond_set_mac_address(struct net_device *bond_dev, void *addr)
3896 {
3897 	struct bonding *bond = bond_dev->priv;
3898 	struct sockaddr *sa = addr, tmp_sa;
3899 	struct slave *slave, *stop_at;
3900 	int res = 0;
3901 	int i;
3902 
3903 	dprintk("bond=%p, name=%s\n", bond, (bond_dev ? bond_dev->name : "None"));
3904 
3905 	if (!is_valid_ether_addr(sa->sa_data)) {
3906 		return -EADDRNOTAVAIL;
3907 	}
3908 
3909 	/* Can't hold bond->lock with bh disabled here since
3910 	 * some base drivers panic. On the other hand we can't
3911 	 * hold bond->lock without bh disabled because we'll
3912 	 * deadlock. The only solution is to rely on the fact
3913 	 * that we're under rtnl_lock here, and the slaves
3914 	 * list won't change. This doesn't solve the problem
3915 	 * of setting the slave's hw address while it is
3916 	 * transmitting, but the assumption is that the base
3917 	 * driver can handle that.
3918 	 *
3919 	 * TODO: figure out a way to safely iterate the slaves
3920 	 * list, but without holding a lock around the actual
3921 	 * call to the base driver.
3922 	 */
3923 
3924 	bond_for_each_slave(bond, slave, i) {
3925 		dprintk("slave %p %s\n", slave, slave->dev->name);
3926 
3927 		if (slave->dev->set_mac_address == NULL) {
3928 			res = -EOPNOTSUPP;
3929 			dprintk("EOPNOTSUPP %s\n", slave->dev->name);
3930 			goto unwind;
3931 		}
3932 
3933 		res = dev_set_mac_address(slave->dev, addr);
3934 		if (res) {
3935 			/* TODO: consider downing the slave
3936 			 * and retry ?
3937 			 * User should expect communications
3938 			 * breakage anyway until ARP finish
3939 			 * updating, so...
3940 			 */
3941 			dprintk("err %d %s\n", res, slave->dev->name);
3942 			goto unwind;
3943 		}
3944 	}
3945 
3946 	/* success */
3947 	memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
3948 	return 0;
3949 
3950 unwind:
3951 	memcpy(tmp_sa.sa_data, bond_dev->dev_addr, bond_dev->addr_len);
3952 	tmp_sa.sa_family = bond_dev->type;
3953 
3954 	/* unwind from head to the slave that failed */
3955 	stop_at = slave;
3956 	bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
3957 		int tmp_res;
3958 
3959 		tmp_res = dev_set_mac_address(slave->dev, &tmp_sa);
3960 		if (tmp_res) {
3961 			dprintk("unwind err %d dev %s\n", tmp_res,
3962 				slave->dev->name);
3963 		}
3964 	}
3965 
3966 	return res;
3967 }
3968 
3969 static int bond_xmit_roundrobin(struct sk_buff *skb, struct net_device *bond_dev)
3970 {
3971 	struct bonding *bond = bond_dev->priv;
3972 	struct slave *slave, *start_at;
3973 	int i;
3974 	int res = 1;
3975 
3976 	read_lock(&bond->lock);
3977 
3978 	if (!BOND_IS_OK(bond)) {
3979 		goto out;
3980 	}
3981 
3982 	read_lock(&bond->curr_slave_lock);
3983 	slave = start_at = bond->curr_active_slave;
3984 	read_unlock(&bond->curr_slave_lock);
3985 
3986 	if (!slave) {
3987 		goto out;
3988 	}
3989 
3990 	bond_for_each_slave_from(bond, slave, i, start_at) {
3991 		if (IS_UP(slave->dev) &&
3992 		    (slave->link == BOND_LINK_UP) &&
3993 		    (slave->state == BOND_STATE_ACTIVE)) {
3994 			res = bond_dev_queue_xmit(bond, skb, slave->dev);
3995 
3996 			write_lock(&bond->curr_slave_lock);
3997 			bond->curr_active_slave = slave->next;
3998 			write_unlock(&bond->curr_slave_lock);
3999 
4000 			break;
4001 		}
4002 	}
4003 
4004 
4005 out:
4006 	if (res) {
4007 		/* no suitable interface, frame not sent */
4008 		dev_kfree_skb(skb);
4009 	}
4010 	read_unlock(&bond->lock);
4011 	return 0;
4012 }
4013 
4014 static void bond_activebackup_xmit_copy(struct sk_buff *skb,
4015                                         struct bonding *bond,
4016                                         struct slave *slave)
4017 {
4018 	struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC);
4019 	struct ethhdr *eth_data;
4020 	u8 *hwaddr;
4021 	int res;
4022 
4023 	if (!skb2) {
4024 		printk(KERN_ERR DRV_NAME ": Error: "
4025 		       "bond_activebackup_xmit_copy(): skb_copy() failed\n");
4026 		return;
4027 	}
4028 
4029 	skb2->mac.raw = (unsigned char *)skb2->data;
4030 	eth_data = eth_hdr(skb2);
4031 
4032 	/* Pick an appropriate source MAC address
4033 	 *	-- use slave's perm MAC addr, unless used by bond
4034 	 *	-- otherwise, borrow active slave's perm MAC addr
4035 	 *	   since that will not be used
4036 	 */
4037 	hwaddr = slave->perm_hwaddr;
4038 	if (!memcmp(eth_data->h_source, hwaddr, ETH_ALEN))
4039 		hwaddr = bond->curr_active_slave->perm_hwaddr;
4040 
4041 	/* Set source MAC address appropriately */
4042 	memcpy(eth_data->h_source, hwaddr, ETH_ALEN);
4043 
4044 	res = bond_dev_queue_xmit(bond, skb2, slave->dev);
4045 	if (res)
4046 		dev_kfree_skb(skb2);
4047 
4048 	return;
4049 }
4050 
4051 /*
4052  * in active-backup mode, we know that bond->curr_active_slave is always valid if
4053  * the bond has a usable interface.
4054  */
4055 static int bond_xmit_activebackup(struct sk_buff *skb, struct net_device *bond_dev)
4056 {
4057 	struct bonding *bond = bond_dev->priv;
4058 	int res = 1;
4059 
4060 	read_lock(&bond->lock);
4061 	read_lock(&bond->curr_slave_lock);
4062 
4063 	if (!BOND_IS_OK(bond)) {
4064 		goto out;
4065 	}
4066 
4067 	if (!bond->curr_active_slave)
4068 		goto out;
4069 
4070 	/* Xmit IGMP frames on all slaves to ensure rapid fail-over
4071 	   for multicast traffic on snooping switches */
4072 	if (skb->protocol == __constant_htons(ETH_P_IP) &&
4073 	    skb->nh.iph->protocol == IPPROTO_IGMP) {
4074 		struct slave *slave, *active_slave;
4075 		int i;
4076 
4077 		active_slave = bond->curr_active_slave;
4078 		bond_for_each_slave_from_to(bond, slave, i, active_slave->next,
4079 		                            active_slave->prev)
4080 			if (IS_UP(slave->dev) &&
4081 			    (slave->link == BOND_LINK_UP))
4082 				bond_activebackup_xmit_copy(skb, bond, slave);
4083 	}
4084 
4085 	res = bond_dev_queue_xmit(bond, skb, bond->curr_active_slave->dev);
4086 
4087 out:
4088 	if (res) {
4089 		/* no suitable interface, frame not sent */
4090 		dev_kfree_skb(skb);
4091 	}
4092 	read_unlock(&bond->curr_slave_lock);
4093 	read_unlock(&bond->lock);
4094 	return 0;
4095 }
4096 
4097 /*
4098  * In bond_xmit_xor() , we determine the output device by using a pre-
4099  * determined xmit_hash_policy(), If the selected device is not enabled,
4100  * find the next active slave.
4101  */
4102 static int bond_xmit_xor(struct sk_buff *skb, struct net_device *bond_dev)
4103 {
4104 	struct bonding *bond = bond_dev->priv;
4105 	struct slave *slave, *start_at;
4106 	int slave_no;
4107 	int i;
4108 	int res = 1;
4109 
4110 	read_lock(&bond->lock);
4111 
4112 	if (!BOND_IS_OK(bond)) {
4113 		goto out;
4114 	}
4115 
4116 	slave_no = bond->xmit_hash_policy(skb, bond_dev, bond->slave_cnt);
4117 
4118 	bond_for_each_slave(bond, slave, i) {
4119 		slave_no--;
4120 		if (slave_no < 0) {
4121 			break;
4122 		}
4123 	}
4124 
4125 	start_at = slave;
4126 
4127 	bond_for_each_slave_from(bond, slave, i, start_at) {
4128 		if (IS_UP(slave->dev) &&
4129 		    (slave->link == BOND_LINK_UP) &&
4130 		    (slave->state == BOND_STATE_ACTIVE)) {
4131 			res = bond_dev_queue_xmit(bond, skb, slave->dev);
4132 			break;
4133 		}
4134 	}
4135 
4136 out:
4137 	if (res) {
4138 		/* no suitable interface, frame not sent */
4139 		dev_kfree_skb(skb);
4140 	}
4141 	read_unlock(&bond->lock);
4142 	return 0;
4143 }
4144 
4145 /*
4146  * in broadcast mode, we send everything to all usable interfaces.
4147  */
4148 static int bond_xmit_broadcast(struct sk_buff *skb, struct net_device *bond_dev)
4149 {
4150 	struct bonding *bond = bond_dev->priv;
4151 	struct slave *slave, *start_at;
4152 	struct net_device *tx_dev = NULL;
4153 	int i;
4154 	int res = 1;
4155 
4156 	read_lock(&bond->lock);
4157 
4158 	if (!BOND_IS_OK(bond)) {
4159 		goto out;
4160 	}
4161 
4162 	read_lock(&bond->curr_slave_lock);
4163 	start_at = bond->curr_active_slave;
4164 	read_unlock(&bond->curr_slave_lock);
4165 
4166 	if (!start_at) {
4167 		goto out;
4168 	}
4169 
4170 	bond_for_each_slave_from(bond, slave, i, start_at) {
4171 		if (IS_UP(slave->dev) &&
4172 		    (slave->link == BOND_LINK_UP) &&
4173 		    (slave->state == BOND_STATE_ACTIVE)) {
4174 			if (tx_dev) {
4175 				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
4176 				if (!skb2) {
4177 					printk(KERN_ERR DRV_NAME
4178 					       ": %s: Error: bond_xmit_broadcast(): "
4179 					       "skb_clone() failed\n",
4180 					       bond_dev->name);
4181 					continue;
4182 				}
4183 
4184 				res = bond_dev_queue_xmit(bond, skb2, tx_dev);
4185 				if (res) {
4186 					dev_kfree_skb(skb2);
4187 					continue;
4188 				}
4189 			}
4190 			tx_dev = slave->dev;
4191 		}
4192 	}
4193 
4194 	if (tx_dev) {
4195 		res = bond_dev_queue_xmit(bond, skb, tx_dev);
4196 	}
4197 
4198 out:
4199 	if (res) {
4200 		/* no suitable interface, frame not sent */
4201 		dev_kfree_skb(skb);
4202 	}
4203 	/* frame sent to all suitable interfaces */
4204 	read_unlock(&bond->lock);
4205 	return 0;
4206 }
4207 
4208 /*------------------------- Device initialization ---------------------------*/
4209 
4210 /*
4211  * set bond mode specific net device operations
4212  */
4213 void bond_set_mode_ops(struct bonding *bond, int mode)
4214 {
4215 	struct net_device *bond_dev = bond->dev;
4216 
4217 	switch (mode) {
4218 	case BOND_MODE_ROUNDROBIN:
4219 		bond_dev->hard_start_xmit = bond_xmit_roundrobin;
4220 		break;
4221 	case BOND_MODE_ACTIVEBACKUP:
4222 		bond_dev->hard_start_xmit = bond_xmit_activebackup;
4223 		break;
4224 	case BOND_MODE_XOR:
4225 		bond_dev->hard_start_xmit = bond_xmit_xor;
4226 		if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER34)
4227 			bond->xmit_hash_policy = bond_xmit_hash_policy_l34;
4228 		else
4229 			bond->xmit_hash_policy = bond_xmit_hash_policy_l2;
4230 		break;
4231 	case BOND_MODE_BROADCAST:
4232 		bond_dev->hard_start_xmit = bond_xmit_broadcast;
4233 		break;
4234 	case BOND_MODE_8023AD:
4235 		bond_set_master_3ad_flags(bond);
4236 		bond_dev->hard_start_xmit = bond_3ad_xmit_xor;
4237 		if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER34)
4238 			bond->xmit_hash_policy = bond_xmit_hash_policy_l34;
4239 		else
4240 			bond->xmit_hash_policy = bond_xmit_hash_policy_l2;
4241 		break;
4242 	case BOND_MODE_ALB:
4243 		bond_set_master_alb_flags(bond);
4244 		/* FALLTHRU */
4245 	case BOND_MODE_TLB:
4246 		bond_dev->hard_start_xmit = bond_alb_xmit;
4247 		bond_dev->set_mac_address = bond_alb_set_mac_address;
4248 		break;
4249 	default:
4250 		/* Should never happen, mode already checked */
4251 		printk(KERN_ERR DRV_NAME
4252 		       ": %s: Error: Unknown bonding mode %d\n",
4253 		       bond_dev->name,
4254 		       mode);
4255 		break;
4256 	}
4257 }
4258 
4259 static void bond_ethtool_get_drvinfo(struct net_device *bond_dev,
4260 				    struct ethtool_drvinfo *drvinfo)
4261 {
4262 	strncpy(drvinfo->driver, DRV_NAME, 32);
4263 	strncpy(drvinfo->version, DRV_VERSION, 32);
4264 	snprintf(drvinfo->fw_version, 32, "%d", BOND_ABI_VERSION);
4265 }
4266 
4267 static const struct ethtool_ops bond_ethtool_ops = {
4268 	.get_tx_csum		= ethtool_op_get_tx_csum,
4269 	.get_tso		= ethtool_op_get_tso,
4270 	.get_ufo		= ethtool_op_get_ufo,
4271 	.get_sg			= ethtool_op_get_sg,
4272 	.get_drvinfo		= bond_ethtool_get_drvinfo,
4273 };
4274 
4275 /*
4276  * Does not allocate but creates a /proc entry.
4277  * Allowed to fail.
4278  */
4279 static int bond_init(struct net_device *bond_dev, struct bond_params *params)
4280 {
4281 	struct bonding *bond = bond_dev->priv;
4282 
4283 	dprintk("Begin bond_init for %s\n", bond_dev->name);
4284 
4285 	/* initialize rwlocks */
4286 	rwlock_init(&bond->lock);
4287 	rwlock_init(&bond->curr_slave_lock);
4288 
4289 	bond->params = *params; /* copy params struct */
4290 
4291 	/* Initialize pointers */
4292 	bond->first_slave = NULL;
4293 	bond->curr_active_slave = NULL;
4294 	bond->current_arp_slave = NULL;
4295 	bond->primary_slave = NULL;
4296 	bond->dev = bond_dev;
4297 	INIT_LIST_HEAD(&bond->vlan_list);
4298 
4299 	/* Initialize the device entry points */
4300 	bond_dev->open = bond_open;
4301 	bond_dev->stop = bond_close;
4302 	bond_dev->get_stats = bond_get_stats;
4303 	bond_dev->do_ioctl = bond_do_ioctl;
4304 	bond_dev->ethtool_ops = &bond_ethtool_ops;
4305 	bond_dev->set_multicast_list = bond_set_multicast_list;
4306 	bond_dev->change_mtu = bond_change_mtu;
4307 	bond_dev->set_mac_address = bond_set_mac_address;
4308 
4309 	bond_set_mode_ops(bond, bond->params.mode);
4310 
4311 	bond_dev->destructor = free_netdev;
4312 
4313 	/* Initialize the device options */
4314 	bond_dev->tx_queue_len = 0;
4315 	bond_dev->flags |= IFF_MASTER|IFF_MULTICAST;
4316 	bond_dev->priv_flags |= IFF_BONDING;
4317 
4318 	/* At first, we block adding VLANs. That's the only way to
4319 	 * prevent problems that occur when adding VLANs over an
4320 	 * empty bond. The block will be removed once non-challenged
4321 	 * slaves are enslaved.
4322 	 */
4323 	bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
4324 
4325 	/* don't acquire bond device's netif_tx_lock when
4326 	 * transmitting */
4327 	bond_dev->features |= NETIF_F_LLTX;
4328 
4329 	/* By default, we declare the bond to be fully
4330 	 * VLAN hardware accelerated capable. Special
4331 	 * care is taken in the various xmit functions
4332 	 * when there are slaves that are not hw accel
4333 	 * capable
4334 	 */
4335 	bond_dev->vlan_rx_register = bond_vlan_rx_register;
4336 	bond_dev->vlan_rx_add_vid  = bond_vlan_rx_add_vid;
4337 	bond_dev->vlan_rx_kill_vid = bond_vlan_rx_kill_vid;
4338 	bond_dev->features |= (NETIF_F_HW_VLAN_TX |
4339 			       NETIF_F_HW_VLAN_RX |
4340 			       NETIF_F_HW_VLAN_FILTER);
4341 
4342 #ifdef CONFIG_PROC_FS
4343 	bond_create_proc_entry(bond);
4344 #endif
4345 
4346 	list_add_tail(&bond->bond_list, &bond_dev_list);
4347 
4348 	return 0;
4349 }
4350 
4351 /* De-initialize device specific data.
4352  * Caller must hold rtnl_lock.
4353  */
4354 void bond_deinit(struct net_device *bond_dev)
4355 {
4356 	struct bonding *bond = bond_dev->priv;
4357 
4358 	list_del(&bond->bond_list);
4359 
4360 #ifdef CONFIG_PROC_FS
4361 	bond_remove_proc_entry(bond);
4362 #endif
4363 }
4364 
4365 /* Unregister and free all bond devices.
4366  * Caller must hold rtnl_lock.
4367  */
4368 static void bond_free_all(void)
4369 {
4370 	struct bonding *bond, *nxt;
4371 
4372 	list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list) {
4373 		struct net_device *bond_dev = bond->dev;
4374 
4375 		bond_mc_list_destroy(bond);
4376 		/* Release the bonded slaves */
4377 		bond_release_all(bond_dev);
4378 		unregister_netdevice(bond_dev);
4379 		bond_deinit(bond_dev);
4380 	}
4381 
4382 #ifdef CONFIG_PROC_FS
4383 	bond_destroy_proc_dir();
4384 #endif
4385 }
4386 
4387 /*------------------------- Module initialization ---------------------------*/
4388 
4389 /*
4390  * Convert string input module parms.  Accept either the
4391  * number of the mode or its string name.
4392  */
4393 int bond_parse_parm(char *mode_arg, struct bond_parm_tbl *tbl)
4394 {
4395 	int i;
4396 
4397 	for (i = 0; tbl[i].modename; i++) {
4398 		if ((isdigit(*mode_arg) &&
4399 		     tbl[i].mode == simple_strtol(mode_arg, NULL, 0)) ||
4400 		    (strncmp(mode_arg, tbl[i].modename,
4401 			     strlen(tbl[i].modename)) == 0)) {
4402 			return tbl[i].mode;
4403 		}
4404 	}
4405 
4406 	return -1;
4407 }
4408 
4409 static int bond_check_params(struct bond_params *params)
4410 {
4411 	int arp_validate_value;
4412 
4413 	/*
4414 	 * Convert string parameters.
4415 	 */
4416 	if (mode) {
4417 		bond_mode = bond_parse_parm(mode, bond_mode_tbl);
4418 		if (bond_mode == -1) {
4419 			printk(KERN_ERR DRV_NAME
4420 			       ": Error: Invalid bonding mode \"%s\"\n",
4421 			       mode == NULL ? "NULL" : mode);
4422 			return -EINVAL;
4423 		}
4424 	}
4425 
4426 	if (xmit_hash_policy) {
4427 		if ((bond_mode != BOND_MODE_XOR) &&
4428 		    (bond_mode != BOND_MODE_8023AD)) {
4429 			printk(KERN_INFO DRV_NAME
4430 			       ": xor_mode param is irrelevant in mode %s\n",
4431 			       bond_mode_name(bond_mode));
4432 		} else {
4433 			xmit_hashtype = bond_parse_parm(xmit_hash_policy,
4434 							xmit_hashtype_tbl);
4435 			if (xmit_hashtype == -1) {
4436 				printk(KERN_ERR DRV_NAME
4437 			       	": Error: Invalid xmit_hash_policy \"%s\"\n",
4438 			       	xmit_hash_policy == NULL ? "NULL" :
4439 				       xmit_hash_policy);
4440 				return -EINVAL;
4441 			}
4442 		}
4443 	}
4444 
4445 	if (lacp_rate) {
4446 		if (bond_mode != BOND_MODE_8023AD) {
4447 			printk(KERN_INFO DRV_NAME
4448 			       ": lacp_rate param is irrelevant in mode %s\n",
4449 			       bond_mode_name(bond_mode));
4450 		} else {
4451 			lacp_fast = bond_parse_parm(lacp_rate, bond_lacp_tbl);
4452 			if (lacp_fast == -1) {
4453 				printk(KERN_ERR DRV_NAME
4454 				       ": Error: Invalid lacp rate \"%s\"\n",
4455 				       lacp_rate == NULL ? "NULL" : lacp_rate);
4456 				return -EINVAL;
4457 			}
4458 		}
4459 	}
4460 
4461 	if (max_bonds < 1 || max_bonds > INT_MAX) {
4462 		printk(KERN_WARNING DRV_NAME
4463 		       ": Warning: max_bonds (%d) not in range %d-%d, so it "
4464 		       "was reset to BOND_DEFAULT_MAX_BONDS (%d)\n",
4465 		       max_bonds, 1, INT_MAX, BOND_DEFAULT_MAX_BONDS);
4466 		max_bonds = BOND_DEFAULT_MAX_BONDS;
4467 	}
4468 
4469 	if (miimon < 0) {
4470 		printk(KERN_WARNING DRV_NAME
4471 		       ": Warning: miimon module parameter (%d), "
4472 		       "not in range 0-%d, so it was reset to %d\n",
4473 		       miimon, INT_MAX, BOND_LINK_MON_INTERV);
4474 		miimon = BOND_LINK_MON_INTERV;
4475 	}
4476 
4477 	if (updelay < 0) {
4478 		printk(KERN_WARNING DRV_NAME
4479 		       ": Warning: updelay module parameter (%d), "
4480 		       "not in range 0-%d, so it was reset to 0\n",
4481 		       updelay, INT_MAX);
4482 		updelay = 0;
4483 	}
4484 
4485 	if (downdelay < 0) {
4486 		printk(KERN_WARNING DRV_NAME
4487 		       ": Warning: downdelay module parameter (%d), "
4488 		       "not in range 0-%d, so it was reset to 0\n",
4489 		       downdelay, INT_MAX);
4490 		downdelay = 0;
4491 	}
4492 
4493 	if ((use_carrier != 0) && (use_carrier != 1)) {
4494 		printk(KERN_WARNING DRV_NAME
4495 		       ": Warning: use_carrier module parameter (%d), "
4496 		       "not of valid value (0/1), so it was set to 1\n",
4497 		       use_carrier);
4498 		use_carrier = 1;
4499 	}
4500 
4501 	/* reset values for 802.3ad */
4502 	if (bond_mode == BOND_MODE_8023AD) {
4503 		if (!miimon) {
4504 			printk(KERN_WARNING DRV_NAME
4505 			       ": Warning: miimon must be specified, "
4506 			       "otherwise bonding will not detect link "
4507 			       "failure, speed and duplex which are "
4508 			       "essential for 802.3ad operation\n");
4509 			printk(KERN_WARNING "Forcing miimon to 100msec\n");
4510 			miimon = 100;
4511 		}
4512 	}
4513 
4514 	/* reset values for TLB/ALB */
4515 	if ((bond_mode == BOND_MODE_TLB) ||
4516 	    (bond_mode == BOND_MODE_ALB)) {
4517 		if (!miimon) {
4518 			printk(KERN_WARNING DRV_NAME
4519 			       ": Warning: miimon must be specified, "
4520 			       "otherwise bonding will not detect link "
4521 			       "failure and link speed which are essential "
4522 			       "for TLB/ALB load balancing\n");
4523 			printk(KERN_WARNING "Forcing miimon to 100msec\n");
4524 			miimon = 100;
4525 		}
4526 	}
4527 
4528 	if (bond_mode == BOND_MODE_ALB) {
4529 		printk(KERN_NOTICE DRV_NAME
4530 		       ": In ALB mode you might experience client "
4531 		       "disconnections upon reconnection of a link if the "
4532 		       "bonding module updelay parameter (%d msec) is "
4533 		       "incompatible with the forwarding delay time of the "
4534 		       "switch\n",
4535 		       updelay);
4536 	}
4537 
4538 	if (!miimon) {
4539 		if (updelay || downdelay) {
4540 			/* just warn the user the up/down delay will have
4541 			 * no effect since miimon is zero...
4542 			 */
4543 			printk(KERN_WARNING DRV_NAME
4544 			       ": Warning: miimon module parameter not set "
4545 			       "and updelay (%d) or downdelay (%d) module "
4546 			       "parameter is set; updelay and downdelay have "
4547 			       "no effect unless miimon is set\n",
4548 			       updelay, downdelay);
4549 		}
4550 	} else {
4551 		/* don't allow arp monitoring */
4552 		if (arp_interval) {
4553 			printk(KERN_WARNING DRV_NAME
4554 			       ": Warning: miimon (%d) and arp_interval (%d) "
4555 			       "can't be used simultaneously, disabling ARP "
4556 			       "monitoring\n",
4557 			       miimon, arp_interval);
4558 			arp_interval = 0;
4559 		}
4560 
4561 		if ((updelay % miimon) != 0) {
4562 			printk(KERN_WARNING DRV_NAME
4563 			       ": Warning: updelay (%d) is not a multiple "
4564 			       "of miimon (%d), updelay rounded to %d ms\n",
4565 			       updelay, miimon, (updelay / miimon) * miimon);
4566 		}
4567 
4568 		updelay /= miimon;
4569 
4570 		if ((downdelay % miimon) != 0) {
4571 			printk(KERN_WARNING DRV_NAME
4572 			       ": Warning: downdelay (%d) is not a multiple "
4573 			       "of miimon (%d), downdelay rounded to %d ms\n",
4574 			       downdelay, miimon,
4575 			       (downdelay / miimon) * miimon);
4576 		}
4577 
4578 		downdelay /= miimon;
4579 	}
4580 
4581 	if (arp_interval < 0) {
4582 		printk(KERN_WARNING DRV_NAME
4583 		       ": Warning: arp_interval module parameter (%d) "
4584 		       ", not in range 0-%d, so it was reset to %d\n",
4585 		       arp_interval, INT_MAX, BOND_LINK_ARP_INTERV);
4586 		arp_interval = BOND_LINK_ARP_INTERV;
4587 	}
4588 
4589 	for (arp_ip_count = 0;
4590 	     (arp_ip_count < BOND_MAX_ARP_TARGETS) && arp_ip_target[arp_ip_count];
4591 	     arp_ip_count++) {
4592 		/* not complete check, but should be good enough to
4593 		   catch mistakes */
4594 		if (!isdigit(arp_ip_target[arp_ip_count][0])) {
4595 			printk(KERN_WARNING DRV_NAME
4596 			       ": Warning: bad arp_ip_target module parameter "
4597 			       "(%s), ARP monitoring will not be performed\n",
4598 			       arp_ip_target[arp_ip_count]);
4599 			arp_interval = 0;
4600 		} else {
4601 			u32 ip = in_aton(arp_ip_target[arp_ip_count]);
4602 			arp_target[arp_ip_count] = ip;
4603 		}
4604 	}
4605 
4606 	if (arp_interval && !arp_ip_count) {
4607 		/* don't allow arping if no arp_ip_target given... */
4608 		printk(KERN_WARNING DRV_NAME
4609 		       ": Warning: arp_interval module parameter (%d) "
4610 		       "specified without providing an arp_ip_target "
4611 		       "parameter, arp_interval was reset to 0\n",
4612 		       arp_interval);
4613 		arp_interval = 0;
4614 	}
4615 
4616 	if (arp_validate) {
4617 		if (bond_mode != BOND_MODE_ACTIVEBACKUP) {
4618 			printk(KERN_ERR DRV_NAME
4619 	       ": arp_validate only supported in active-backup mode\n");
4620 			return -EINVAL;
4621 		}
4622 		if (!arp_interval) {
4623 			printk(KERN_ERR DRV_NAME
4624 			       ": arp_validate requires arp_interval\n");
4625 			return -EINVAL;
4626 		}
4627 
4628 		arp_validate_value = bond_parse_parm(arp_validate,
4629 						     arp_validate_tbl);
4630 		if (arp_validate_value == -1) {
4631 			printk(KERN_ERR DRV_NAME
4632 			       ": Error: invalid arp_validate \"%s\"\n",
4633 			       arp_validate == NULL ? "NULL" : arp_validate);
4634 			return -EINVAL;
4635 		}
4636 	} else
4637 		arp_validate_value = 0;
4638 
4639 	if (miimon) {
4640 		printk(KERN_INFO DRV_NAME
4641 		       ": MII link monitoring set to %d ms\n",
4642 		       miimon);
4643 	} else if (arp_interval) {
4644 		int i;
4645 
4646 		printk(KERN_INFO DRV_NAME
4647 		       ": ARP monitoring set to %d ms, validate %s, with %d target(s):",
4648 		       arp_interval,
4649 		       arp_validate_tbl[arp_validate_value].modename,
4650 		       arp_ip_count);
4651 
4652 		for (i = 0; i < arp_ip_count; i++)
4653 			printk (" %s", arp_ip_target[i]);
4654 
4655 		printk("\n");
4656 
4657 	} else {
4658 		/* miimon and arp_interval not set, we need one so things
4659 		 * work as expected, see bonding.txt for details
4660 		 */
4661 		printk(KERN_WARNING DRV_NAME
4662 		       ": Warning: either miimon or arp_interval and "
4663 		       "arp_ip_target module parameters must be specified, "
4664 		       "otherwise bonding will not detect link failures! see "
4665 		       "bonding.txt for details.\n");
4666 	}
4667 
4668 	if (primary && !USES_PRIMARY(bond_mode)) {
4669 		/* currently, using a primary only makes sense
4670 		 * in active backup, TLB or ALB modes
4671 		 */
4672 		printk(KERN_WARNING DRV_NAME
4673 		       ": Warning: %s primary device specified but has no "
4674 		       "effect in %s mode\n",
4675 		       primary, bond_mode_name(bond_mode));
4676 		primary = NULL;
4677 	}
4678 
4679 	/* fill params struct with the proper values */
4680 	params->mode = bond_mode;
4681 	params->xmit_policy = xmit_hashtype;
4682 	params->miimon = miimon;
4683 	params->arp_interval = arp_interval;
4684 	params->arp_validate = arp_validate_value;
4685 	params->updelay = updelay;
4686 	params->downdelay = downdelay;
4687 	params->use_carrier = use_carrier;
4688 	params->lacp_fast = lacp_fast;
4689 	params->primary[0] = 0;
4690 
4691 	if (primary) {
4692 		strncpy(params->primary, primary, IFNAMSIZ);
4693 		params->primary[IFNAMSIZ - 1] = 0;
4694 	}
4695 
4696 	memcpy(params->arp_targets, arp_target, sizeof(arp_target));
4697 
4698 	return 0;
4699 }
4700 
4701 static struct lock_class_key bonding_netdev_xmit_lock_key;
4702 
4703 /* Create a new bond based on the specified name and bonding parameters.
4704  * If name is NULL, obtain a suitable "bond%d" name for us.
4705  * Caller must NOT hold rtnl_lock; we need to release it here before we
4706  * set up our sysfs entries.
4707  */
4708 int bond_create(char *name, struct bond_params *params, struct bonding **newbond)
4709 {
4710 	struct net_device *bond_dev;
4711 	int res;
4712 
4713 	rtnl_lock();
4714 	bond_dev = alloc_netdev(sizeof(struct bonding), name ? name : "",
4715 				ether_setup);
4716 	if (!bond_dev) {
4717 		printk(KERN_ERR DRV_NAME
4718 		       ": %s: eek! can't alloc netdev!\n",
4719 		       name);
4720 		res = -ENOMEM;
4721 		goto out_rtnl;
4722 	}
4723 
4724 	if (!name) {
4725 		res = dev_alloc_name(bond_dev, "bond%d");
4726 		if (res < 0)
4727 			goto out_netdev;
4728 	}
4729 
4730 	/* bond_init() must be called after dev_alloc_name() (for the
4731 	 * /proc files), but before register_netdevice(), because we
4732 	 * need to set function pointers.
4733 	 */
4734 
4735 	res = bond_init(bond_dev, params);
4736 	if (res < 0) {
4737 		goto out_netdev;
4738 	}
4739 
4740 	SET_MODULE_OWNER(bond_dev);
4741 
4742 	res = register_netdevice(bond_dev);
4743 	if (res < 0) {
4744 		goto out_bond;
4745 	}
4746 
4747 	lockdep_set_class(&bond_dev->_xmit_lock, &bonding_netdev_xmit_lock_key);
4748 
4749 	if (newbond)
4750 		*newbond = bond_dev->priv;
4751 
4752 	netif_carrier_off(bond_dev);
4753 
4754 	rtnl_unlock(); /* allows sysfs registration of net device */
4755 	res = bond_create_sysfs_entry(bond_dev->priv);
4756 	if (res < 0) {
4757 		rtnl_lock();
4758 		goto out_bond;
4759 	}
4760 
4761 	return 0;
4762 
4763 out_bond:
4764 	bond_deinit(bond_dev);
4765 out_netdev:
4766 	free_netdev(bond_dev);
4767 out_rtnl:
4768 	rtnl_unlock();
4769 	return res;
4770 }
4771 
4772 static int __init bonding_init(void)
4773 {
4774 	int i;
4775 	int res;
4776 
4777 	printk(KERN_INFO "%s", version);
4778 
4779 	res = bond_check_params(&bonding_defaults);
4780 	if (res) {
4781 		goto out;
4782 	}
4783 
4784 #ifdef CONFIG_PROC_FS
4785 	bond_create_proc_dir();
4786 #endif
4787 	for (i = 0; i < max_bonds; i++) {
4788 		res = bond_create(NULL, &bonding_defaults, NULL);
4789 		if (res)
4790 			goto err;
4791 	}
4792 
4793 	res = bond_create_sysfs();
4794 	if (res)
4795 		goto err;
4796 
4797 	register_netdevice_notifier(&bond_netdev_notifier);
4798 	register_inetaddr_notifier(&bond_inetaddr_notifier);
4799 
4800 	goto out;
4801 err:
4802 	rtnl_lock();
4803 	bond_free_all();
4804 	bond_destroy_sysfs();
4805 	rtnl_unlock();
4806 out:
4807 	return res;
4808 
4809 }
4810 
4811 static void __exit bonding_exit(void)
4812 {
4813 	unregister_netdevice_notifier(&bond_netdev_notifier);
4814 	unregister_inetaddr_notifier(&bond_inetaddr_notifier);
4815 
4816 	rtnl_lock();
4817 	bond_free_all();
4818 	bond_destroy_sysfs();
4819 	rtnl_unlock();
4820 }
4821 
4822 module_init(bonding_init);
4823 module_exit(bonding_exit);
4824 MODULE_LICENSE("GPL");
4825 MODULE_VERSION(DRV_VERSION);
4826 MODULE_DESCRIPTION(DRV_DESCRIPTION ", v" DRV_VERSION);
4827 MODULE_AUTHOR("Thomas Davis, tadavis@lbl.gov and many others");
4828 MODULE_SUPPORTED_DEVICE("most ethernet devices");
4829 
4830 /*
4831  * Local variables:
4832  *  c-indent-level: 8
4833  *  c-basic-offset: 8
4834  *  tab-width: 8
4835  * End:
4836  */
4837 
4838