xref: /linux/drivers/net/bonding/bond_main.c (revision b0148a98ec5151fec82064d95f11eb9efbc628ea)
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/sched.h>
39 #include <linux/types.h>
40 #include <linux/fcntl.h>
41 #include <linux/interrupt.h>
42 #include <linux/ptrace.h>
43 #include <linux/ioport.h>
44 #include <linux/in.h>
45 #include <net/ip.h>
46 #include <linux/ip.h>
47 #include <linux/tcp.h>
48 #include <linux/udp.h>
49 #include <linux/slab.h>
50 #include <linux/string.h>
51 #include <linux/init.h>
52 #include <linux/timer.h>
53 #include <linux/socket.h>
54 #include <linux/ctype.h>
55 #include <linux/inet.h>
56 #include <linux/bitops.h>
57 #include <asm/system.h>
58 #include <asm/io.h>
59 #include <asm/dma.h>
60 #include <asm/uaccess.h>
61 #include <linux/errno.h>
62 #include <linux/netdevice.h>
63 #include <linux/inetdevice.h>
64 #include <linux/etherdevice.h>
65 #include <linux/skbuff.h>
66 #include <net/sock.h>
67 #include <linux/rtnetlink.h>
68 #include <linux/proc_fs.h>
69 #include <linux/seq_file.h>
70 #include <linux/smp.h>
71 #include <linux/if_ether.h>
72 #include <net/arp.h>
73 #include <linux/mii.h>
74 #include <linux/ethtool.h>
75 #include <linux/if_vlan.h>
76 #include <linux/if_bonding.h>
77 #include <net/route.h>
78 #include "bonding.h"
79 #include "bond_3ad.h"
80 #include "bond_alb.h"
81 
82 /*---------------------------- Module parameters ----------------------------*/
83 
84 /* monitor all links that often (in milliseconds). <=0 disables monitoring */
85 #define BOND_LINK_MON_INTERV	0
86 #define BOND_LINK_ARP_INTERV	0
87 
88 static int max_bonds	= BOND_DEFAULT_MAX_BONDS;
89 static int miimon	= BOND_LINK_MON_INTERV;
90 static int updelay	= 0;
91 static int downdelay	= 0;
92 static int use_carrier	= 1;
93 static char *mode	= NULL;
94 static char *primary	= NULL;
95 static char *lacp_rate	= NULL;
96 static char *xmit_hash_policy = NULL;
97 static int arp_interval = BOND_LINK_ARP_INTERV;
98 static char *arp_ip_target[BOND_MAX_ARP_TARGETS] = { NULL, };
99 static char *arp_validate = NULL;
100 struct bond_params bonding_defaults;
101 
102 module_param(max_bonds, int, 0);
103 MODULE_PARM_DESC(max_bonds, "Max number of bonded devices");
104 module_param(miimon, int, 0);
105 MODULE_PARM_DESC(miimon, "Link check interval in milliseconds");
106 module_param(updelay, int, 0);
107 MODULE_PARM_DESC(updelay, "Delay before considering link up, in milliseconds");
108 module_param(downdelay, int, 0);
109 MODULE_PARM_DESC(downdelay, "Delay before considering link down, "
110 			    "in milliseconds");
111 module_param(use_carrier, int, 0);
112 MODULE_PARM_DESC(use_carrier, "Use netif_carrier_ok (vs MII ioctls) in miimon; "
113 			      "0 for off, 1 for on (default)");
114 module_param(mode, charp, 0);
115 MODULE_PARM_DESC(mode, "Mode of operation : 0 for balance-rr, "
116 		       "1 for active-backup, 2 for balance-xor, "
117 		       "3 for broadcast, 4 for 802.3ad, 5 for balance-tlb, "
118 		       "6 for balance-alb");
119 module_param(primary, charp, 0);
120 MODULE_PARM_DESC(primary, "Primary network device to use");
121 module_param(lacp_rate, charp, 0);
122 MODULE_PARM_DESC(lacp_rate, "LACPDU tx rate to request from 802.3ad partner "
123 			    "(slow/fast)");
124 module_param(xmit_hash_policy, charp, 0);
125 MODULE_PARM_DESC(xmit_hash_policy, "XOR hashing method: 0 for layer 2 (default)"
126 				   ", 1 for layer 3+4");
127 module_param(arp_interval, int, 0);
128 MODULE_PARM_DESC(arp_interval, "arp interval in milliseconds");
129 module_param_array(arp_ip_target, charp, NULL, 0);
130 MODULE_PARM_DESC(arp_ip_target, "arp targets in n.n.n.n form");
131 module_param(arp_validate, charp, 0);
132 MODULE_PARM_DESC(arp_validate, "validate src/dst of ARP probes: none (default), active, backup or all");
133 
134 /*----------------------------- Global variables ----------------------------*/
135 
136 static const char * const version =
137 	DRV_DESCRIPTION ": v" DRV_VERSION " (" DRV_RELDATE ")\n";
138 
139 LIST_HEAD(bond_dev_list);
140 
141 #ifdef CONFIG_PROC_FS
142 static struct proc_dir_entry *bond_proc_dir = NULL;
143 #endif
144 
145 extern struct rw_semaphore bonding_rwsem;
146 static u32 arp_target[BOND_MAX_ARP_TARGETS] = { 0, } ;
147 static int arp_ip_count	= 0;
148 static int bond_mode	= BOND_MODE_ROUNDROBIN;
149 static int xmit_hashtype= BOND_XMIT_POLICY_LAYER2;
150 static int lacp_fast	= 0;
151 
152 
153 struct bond_parm_tbl bond_lacp_tbl[] = {
154 {	"slow",		AD_LACP_SLOW},
155 {	"fast",		AD_LACP_FAST},
156 {	NULL,		-1},
157 };
158 
159 struct bond_parm_tbl bond_mode_tbl[] = {
160 {	"balance-rr",		BOND_MODE_ROUNDROBIN},
161 {	"active-backup",	BOND_MODE_ACTIVEBACKUP},
162 {	"balance-xor",		BOND_MODE_XOR},
163 {	"broadcast",		BOND_MODE_BROADCAST},
164 {	"802.3ad",		BOND_MODE_8023AD},
165 {	"balance-tlb",		BOND_MODE_TLB},
166 {	"balance-alb",		BOND_MODE_ALB},
167 {	NULL,			-1},
168 };
169 
170 struct bond_parm_tbl xmit_hashtype_tbl[] = {
171 {	"layer2",		BOND_XMIT_POLICY_LAYER2},
172 {	"layer3+4",		BOND_XMIT_POLICY_LAYER34},
173 {	NULL,			-1},
174 };
175 
176 struct bond_parm_tbl arp_validate_tbl[] = {
177 {	"none",			BOND_ARP_VALIDATE_NONE},
178 {	"active",		BOND_ARP_VALIDATE_ACTIVE},
179 {	"backup",		BOND_ARP_VALIDATE_BACKUP},
180 {	"all",			BOND_ARP_VALIDATE_ALL},
181 {	NULL,			-1},
182 };
183 
184 /*-------------------------- Forward declarations ---------------------------*/
185 
186 static void bond_send_gratuitous_arp(struct bonding *bond);
187 
188 /*---------------------------- General routines -----------------------------*/
189 
190 const char *bond_mode_name(int mode)
191 {
192 	switch (mode) {
193 	case BOND_MODE_ROUNDROBIN :
194 		return "load balancing (round-robin)";
195 	case BOND_MODE_ACTIVEBACKUP :
196 		return "fault-tolerance (active-backup)";
197 	case BOND_MODE_XOR :
198 		return "load balancing (xor)";
199 	case BOND_MODE_BROADCAST :
200 		return "fault-tolerance (broadcast)";
201 	case BOND_MODE_8023AD:
202 		return "IEEE 802.3ad Dynamic link aggregation";
203 	case BOND_MODE_TLB:
204 		return "transmit load balancing";
205 	case BOND_MODE_ALB:
206 		return "adaptive load balancing";
207 	default:
208 		return "unknown";
209 	}
210 }
211 
212 /*---------------------------------- VLAN -----------------------------------*/
213 
214 /**
215  * bond_add_vlan - add a new vlan id on bond
216  * @bond: bond that got the notification
217  * @vlan_id: the vlan id to add
218  *
219  * Returns -ENOMEM if allocation failed.
220  */
221 static int bond_add_vlan(struct bonding *bond, unsigned short vlan_id)
222 {
223 	struct vlan_entry *vlan;
224 
225 	dprintk("bond: %s, vlan id %d\n",
226 		(bond ? bond->dev->name: "None"), vlan_id);
227 
228 	vlan = kmalloc(sizeof(struct vlan_entry), GFP_KERNEL);
229 	if (!vlan) {
230 		return -ENOMEM;
231 	}
232 
233 	INIT_LIST_HEAD(&vlan->vlan_list);
234 	vlan->vlan_id = vlan_id;
235 	vlan->vlan_ip = 0;
236 
237 	write_lock_bh(&bond->lock);
238 
239 	list_add_tail(&vlan->vlan_list, &bond->vlan_list);
240 
241 	write_unlock_bh(&bond->lock);
242 
243 	dprintk("added VLAN ID %d on bond %s\n", vlan_id, bond->dev->name);
244 
245 	return 0;
246 }
247 
248 /**
249  * bond_del_vlan - delete a vlan id from bond
250  * @bond: bond that got the notification
251  * @vlan_id: the vlan id to delete
252  *
253  * returns -ENODEV if @vlan_id was not found in @bond.
254  */
255 static int bond_del_vlan(struct bonding *bond, unsigned short vlan_id)
256 {
257 	struct vlan_entry *vlan, *next;
258 	int res = -ENODEV;
259 
260 	dprintk("bond: %s, vlan id %d\n", bond->dev->name, vlan_id);
261 
262 	write_lock_bh(&bond->lock);
263 
264 	list_for_each_entry_safe(vlan, next, &bond->vlan_list, vlan_list) {
265 		if (vlan->vlan_id == vlan_id) {
266 			list_del(&vlan->vlan_list);
267 
268 			if ((bond->params.mode == BOND_MODE_TLB) ||
269 			    (bond->params.mode == BOND_MODE_ALB)) {
270 				bond_alb_clear_vlan(bond, vlan_id);
271 			}
272 
273 			dprintk("removed VLAN ID %d from bond %s\n", vlan_id,
274 				bond->dev->name);
275 
276 			kfree(vlan);
277 
278 			if (list_empty(&bond->vlan_list) &&
279 			    (bond->slave_cnt == 0)) {
280 				/* Last VLAN removed and no slaves, so
281 				 * restore block on adding VLANs. This will
282 				 * be removed once new slaves that are not
283 				 * VLAN challenged will be added.
284 				 */
285 				bond->dev->features |= NETIF_F_VLAN_CHALLENGED;
286 			}
287 
288 			res = 0;
289 			goto out;
290 		}
291 	}
292 
293 	dprintk("couldn't find VLAN ID %d in bond %s\n", vlan_id,
294 		bond->dev->name);
295 
296 out:
297 	write_unlock_bh(&bond->lock);
298 	return res;
299 }
300 
301 /**
302  * bond_has_challenged_slaves
303  * @bond: the bond we're working on
304  *
305  * Searches the slave list. Returns 1 if a vlan challenged slave
306  * was found, 0 otherwise.
307  *
308  * Assumes bond->lock is held.
309  */
310 static int bond_has_challenged_slaves(struct bonding *bond)
311 {
312 	struct slave *slave;
313 	int i;
314 
315 	bond_for_each_slave(bond, slave, i) {
316 		if (slave->dev->features & NETIF_F_VLAN_CHALLENGED) {
317 			dprintk("found VLAN challenged slave - %s\n",
318 				slave->dev->name);
319 			return 1;
320 		}
321 	}
322 
323 	dprintk("no VLAN challenged slaves found\n");
324 	return 0;
325 }
326 
327 /**
328  * bond_next_vlan - safely skip to the next item in the vlans list.
329  * @bond: the bond we're working on
330  * @curr: item we're advancing from
331  *
332  * Returns %NULL if list is empty, bond->next_vlan if @curr is %NULL,
333  * or @curr->next otherwise (even if it is @curr itself again).
334  *
335  * Caller must hold bond->lock
336  */
337 struct vlan_entry *bond_next_vlan(struct bonding *bond, struct vlan_entry *curr)
338 {
339 	struct vlan_entry *next, *last;
340 
341 	if (list_empty(&bond->vlan_list)) {
342 		return NULL;
343 	}
344 
345 	if (!curr) {
346 		next = list_entry(bond->vlan_list.next,
347 				  struct vlan_entry, vlan_list);
348 	} else {
349 		last = list_entry(bond->vlan_list.prev,
350 				  struct vlan_entry, vlan_list);
351 		if (last == curr) {
352 			next = list_entry(bond->vlan_list.next,
353 					  struct vlan_entry, vlan_list);
354 		} else {
355 			next = list_entry(curr->vlan_list.next,
356 					  struct vlan_entry, vlan_list);
357 		}
358 	}
359 
360 	return next;
361 }
362 
363 /**
364  * bond_dev_queue_xmit - Prepare skb for xmit.
365  *
366  * @bond: bond device that got this skb for tx.
367  * @skb: hw accel VLAN tagged skb to transmit
368  * @slave_dev: slave that is supposed to xmit this skbuff
369  *
370  * When the bond gets an skb to transmit that is
371  * already hardware accelerated VLAN tagged, and it
372  * needs to relay this skb to a slave that is not
373  * hw accel capable, the skb needs to be "unaccelerated",
374  * i.e. strip the hwaccel tag and re-insert it as part
375  * of the payload.
376  */
377 int bond_dev_queue_xmit(struct bonding *bond, struct sk_buff *skb, struct net_device *slave_dev)
378 {
379 	unsigned short vlan_id;
380 
381 	if (!list_empty(&bond->vlan_list) &&
382 	    !(slave_dev->features & NETIF_F_HW_VLAN_TX) &&
383 	    vlan_get_tag(skb, &vlan_id) == 0) {
384 		skb->dev = slave_dev;
385 		skb = vlan_put_tag(skb, vlan_id);
386 		if (!skb) {
387 			/* vlan_put_tag() frees the skb in case of error,
388 			 * so return success here so the calling functions
389 			 * won't attempt to free is again.
390 			 */
391 			return 0;
392 		}
393 	} else {
394 		skb->dev = slave_dev;
395 	}
396 
397 	skb->priority = 1;
398 	dev_queue_xmit(skb);
399 
400 	return 0;
401 }
402 
403 /*
404  * In the following 3 functions, bond_vlan_rx_register(), bond_vlan_rx_add_vid
405  * and bond_vlan_rx_kill_vid, We don't protect the slave list iteration with a
406  * lock because:
407  * a. This operation is performed in IOCTL context,
408  * b. The operation is protected by the RTNL semaphore in the 8021q code,
409  * c. Holding a lock with BH disabled while directly calling a base driver
410  *    entry point is generally a BAD idea.
411  *
412  * The design of synchronization/protection for this operation in the 8021q
413  * module is good for one or more VLAN devices over a single physical device
414  * and cannot be extended for a teaming solution like bonding, so there is a
415  * potential race condition here where a net device from the vlan group might
416  * be referenced (either by a base driver or the 8021q code) while it is being
417  * removed from the system. However, it turns out we're not making matters
418  * worse, and if it works for regular VLAN usage it will work here too.
419 */
420 
421 /**
422  * bond_vlan_rx_register - Propagates registration to slaves
423  * @bond_dev: bonding net device that got called
424  * @grp: vlan group being registered
425  */
426 static void bond_vlan_rx_register(struct net_device *bond_dev, struct vlan_group *grp)
427 {
428 	struct bonding *bond = bond_dev->priv;
429 	struct slave *slave;
430 	int i;
431 
432 	bond->vlgrp = grp;
433 
434 	bond_for_each_slave(bond, slave, i) {
435 		struct net_device *slave_dev = slave->dev;
436 
437 		if ((slave_dev->features & NETIF_F_HW_VLAN_RX) &&
438 		    slave_dev->vlan_rx_register) {
439 			slave_dev->vlan_rx_register(slave_dev, grp);
440 		}
441 	}
442 }
443 
444 /**
445  * bond_vlan_rx_add_vid - Propagates adding an id to slaves
446  * @bond_dev: bonding net device that got called
447  * @vid: vlan id being added
448  */
449 static void bond_vlan_rx_add_vid(struct net_device *bond_dev, uint16_t vid)
450 {
451 	struct bonding *bond = bond_dev->priv;
452 	struct slave *slave;
453 	int i, res;
454 
455 	bond_for_each_slave(bond, slave, i) {
456 		struct net_device *slave_dev = slave->dev;
457 
458 		if ((slave_dev->features & NETIF_F_HW_VLAN_FILTER) &&
459 		    slave_dev->vlan_rx_add_vid) {
460 			slave_dev->vlan_rx_add_vid(slave_dev, vid);
461 		}
462 	}
463 
464 	res = bond_add_vlan(bond, vid);
465 	if (res) {
466 		printk(KERN_ERR DRV_NAME
467 		       ": %s: Error: Failed to add vlan id %d\n",
468 		       bond_dev->name, vid);
469 	}
470 }
471 
472 /**
473  * bond_vlan_rx_kill_vid - Propagates deleting an id to slaves
474  * @bond_dev: bonding net device that got called
475  * @vid: vlan id being removed
476  */
477 static void bond_vlan_rx_kill_vid(struct net_device *bond_dev, uint16_t vid)
478 {
479 	struct bonding *bond = bond_dev->priv;
480 	struct slave *slave;
481 	struct net_device *vlan_dev;
482 	int i, res;
483 
484 	bond_for_each_slave(bond, slave, i) {
485 		struct net_device *slave_dev = slave->dev;
486 
487 		if ((slave_dev->features & NETIF_F_HW_VLAN_FILTER) &&
488 		    slave_dev->vlan_rx_kill_vid) {
489 			/* Save and then restore vlan_dev in the grp array,
490 			 * since the slave's driver might clear it.
491 			 */
492 			vlan_dev = bond->vlgrp->vlan_devices[vid];
493 			slave_dev->vlan_rx_kill_vid(slave_dev, vid);
494 			bond->vlgrp->vlan_devices[vid] = vlan_dev;
495 		}
496 	}
497 
498 	res = bond_del_vlan(bond, vid);
499 	if (res) {
500 		printk(KERN_ERR DRV_NAME
501 		       ": %s: Error: Failed to remove vlan id %d\n",
502 		       bond_dev->name, vid);
503 	}
504 }
505 
506 static void bond_add_vlans_on_slave(struct bonding *bond, struct net_device *slave_dev)
507 {
508 	struct vlan_entry *vlan;
509 
510 	write_lock_bh(&bond->lock);
511 
512 	if (list_empty(&bond->vlan_list)) {
513 		goto out;
514 	}
515 
516 	if ((slave_dev->features & NETIF_F_HW_VLAN_RX) &&
517 	    slave_dev->vlan_rx_register) {
518 		slave_dev->vlan_rx_register(slave_dev, bond->vlgrp);
519 	}
520 
521 	if (!(slave_dev->features & NETIF_F_HW_VLAN_FILTER) ||
522 	    !(slave_dev->vlan_rx_add_vid)) {
523 		goto out;
524 	}
525 
526 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
527 		slave_dev->vlan_rx_add_vid(slave_dev, vlan->vlan_id);
528 	}
529 
530 out:
531 	write_unlock_bh(&bond->lock);
532 }
533 
534 static void bond_del_vlans_from_slave(struct bonding *bond, struct net_device *slave_dev)
535 {
536 	struct vlan_entry *vlan;
537 	struct net_device *vlan_dev;
538 
539 	write_lock_bh(&bond->lock);
540 
541 	if (list_empty(&bond->vlan_list)) {
542 		goto out;
543 	}
544 
545 	if (!(slave_dev->features & NETIF_F_HW_VLAN_FILTER) ||
546 	    !(slave_dev->vlan_rx_kill_vid)) {
547 		goto unreg;
548 	}
549 
550 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
551 		/* Save and then restore vlan_dev in the grp array,
552 		 * since the slave's driver might clear it.
553 		 */
554 		vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
555 		slave_dev->vlan_rx_kill_vid(slave_dev, vlan->vlan_id);
556 		bond->vlgrp->vlan_devices[vlan->vlan_id] = vlan_dev;
557 	}
558 
559 unreg:
560 	if ((slave_dev->features & NETIF_F_HW_VLAN_RX) &&
561 	    slave_dev->vlan_rx_register) {
562 		slave_dev->vlan_rx_register(slave_dev, NULL);
563 	}
564 
565 out:
566 	write_unlock_bh(&bond->lock);
567 }
568 
569 /*------------------------------- Link status -------------------------------*/
570 
571 /*
572  * Set the carrier state for the master according to the state of its
573  * slaves.  If any slaves are up, the master is up.  In 802.3ad mode,
574  * do special 802.3ad magic.
575  *
576  * Returns zero if carrier state does not change, nonzero if it does.
577  */
578 static int bond_set_carrier(struct bonding *bond)
579 {
580 	struct slave *slave;
581 	int i;
582 
583 	if (bond->slave_cnt == 0)
584 		goto down;
585 
586 	if (bond->params.mode == BOND_MODE_8023AD)
587 		return bond_3ad_set_carrier(bond);
588 
589 	bond_for_each_slave(bond, slave, i) {
590 		if (slave->link == BOND_LINK_UP) {
591 			if (!netif_carrier_ok(bond->dev)) {
592 				netif_carrier_on(bond->dev);
593 				return 1;
594 			}
595 			return 0;
596 		}
597 	}
598 
599 down:
600 	if (netif_carrier_ok(bond->dev)) {
601 		netif_carrier_off(bond->dev);
602 		return 1;
603 	}
604 	return 0;
605 }
606 
607 /*
608  * Get link speed and duplex from the slave's base driver
609  * using ethtool. If for some reason the call fails or the
610  * values are invalid, fake speed and duplex to 100/Full
611  * and return error.
612  */
613 static int bond_update_speed_duplex(struct slave *slave)
614 {
615 	struct net_device *slave_dev = slave->dev;
616 	static int (* ioctl)(struct net_device *, struct ifreq *, int);
617 	struct ifreq ifr;
618 	struct ethtool_cmd etool;
619 
620 	/* Fake speed and duplex */
621 	slave->speed = SPEED_100;
622 	slave->duplex = DUPLEX_FULL;
623 
624 	if (slave_dev->ethtool_ops) {
625 		int res;
626 
627 		if (!slave_dev->ethtool_ops->get_settings) {
628 			return -1;
629 		}
630 
631 		res = slave_dev->ethtool_ops->get_settings(slave_dev, &etool);
632 		if (res < 0) {
633 			return -1;
634 		}
635 
636 		goto verify;
637 	}
638 
639 	ioctl = slave_dev->do_ioctl;
640 	strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
641 	etool.cmd = ETHTOOL_GSET;
642 	ifr.ifr_data = (char*)&etool;
643 	if (!ioctl || (IOCTL(slave_dev, &ifr, SIOCETHTOOL) < 0)) {
644 		return -1;
645 	}
646 
647 verify:
648 	switch (etool.speed) {
649 	case SPEED_10:
650 	case SPEED_100:
651 	case SPEED_1000:
652 	case SPEED_10000:
653 		break;
654 	default:
655 		return -1;
656 	}
657 
658 	switch (etool.duplex) {
659 	case DUPLEX_FULL:
660 	case DUPLEX_HALF:
661 		break;
662 	default:
663 		return -1;
664 	}
665 
666 	slave->speed = etool.speed;
667 	slave->duplex = etool.duplex;
668 
669 	return 0;
670 }
671 
672 /*
673  * if <dev> supports MII link status reporting, check its link status.
674  *
675  * We either do MII/ETHTOOL ioctls, or check netif_carrier_ok(),
676  * depening upon the setting of the use_carrier parameter.
677  *
678  * Return either BMSR_LSTATUS, meaning that the link is up (or we
679  * can't tell and just pretend it is), or 0, meaning that the link is
680  * down.
681  *
682  * If reporting is non-zero, instead of faking link up, return -1 if
683  * both ETHTOOL and MII ioctls fail (meaning the device does not
684  * support them).  If use_carrier is set, return whatever it says.
685  * It'd be nice if there was a good way to tell if a driver supports
686  * netif_carrier, but there really isn't.
687  */
688 static int bond_check_dev_link(struct bonding *bond, struct net_device *slave_dev, int reporting)
689 {
690 	static int (* ioctl)(struct net_device *, struct ifreq *, int);
691 	struct ifreq ifr;
692 	struct mii_ioctl_data *mii;
693 	struct ethtool_value etool;
694 
695 	if (bond->params.use_carrier) {
696 		return netif_carrier_ok(slave_dev) ? BMSR_LSTATUS : 0;
697 	}
698 
699 	ioctl = slave_dev->do_ioctl;
700 	if (ioctl) {
701 		/* TODO: set pointer to correct ioctl on a per team member */
702 		/*       bases to make this more efficient. that is, once  */
703 		/*       we determine the correct ioctl, we will always    */
704 		/*       call it and not the others for that team          */
705 		/*       member.                                           */
706 
707 		/*
708 		 * We cannot assume that SIOCGMIIPHY will also read a
709 		 * register; not all network drivers (e.g., e100)
710 		 * support that.
711 		 */
712 
713 		/* Yes, the mii is overlaid on the ifreq.ifr_ifru */
714 		strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
715 		mii = if_mii(&ifr);
716 		if (IOCTL(slave_dev, &ifr, SIOCGMIIPHY) == 0) {
717 			mii->reg_num = MII_BMSR;
718 			if (IOCTL(slave_dev, &ifr, SIOCGMIIREG) == 0) {
719 				return (mii->val_out & BMSR_LSTATUS);
720 			}
721 		}
722 	}
723 
724 	/* try SIOCETHTOOL ioctl, some drivers cache ETHTOOL_GLINK */
725 	/* for a period of time so we attempt to get link status   */
726 	/* from it last if the above MII ioctls fail...            */
727 	if (slave_dev->ethtool_ops) {
728 		if (slave_dev->ethtool_ops->get_link) {
729 			u32 link;
730 
731 			link = slave_dev->ethtool_ops->get_link(slave_dev);
732 
733 			return link ? BMSR_LSTATUS : 0;
734 		}
735 	}
736 
737 	if (ioctl) {
738 		strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
739 		etool.cmd = ETHTOOL_GLINK;
740 		ifr.ifr_data = (char*)&etool;
741 		if (IOCTL(slave_dev, &ifr, SIOCETHTOOL) == 0) {
742 			if (etool.data == 1) {
743 				return BMSR_LSTATUS;
744 			} else {
745 				dprintk("SIOCETHTOOL shows link down\n");
746 				return 0;
747 			}
748 		}
749 	}
750 
751 	/*
752 	 * If reporting, report that either there's no dev->do_ioctl,
753 	 * or both SIOCGMIIREG and SIOCETHTOOL failed (meaning that we
754 	 * cannot report link status).  If not reporting, pretend
755 	 * we're ok.
756 	 */
757 	return (reporting ? -1 : BMSR_LSTATUS);
758 }
759 
760 /*----------------------------- Multicast list ------------------------------*/
761 
762 /*
763  * Returns 0 if dmi1 and dmi2 are the same, non-0 otherwise
764  */
765 static inline int bond_is_dmi_same(struct dev_mc_list *dmi1, struct dev_mc_list *dmi2)
766 {
767 	return memcmp(dmi1->dmi_addr, dmi2->dmi_addr, dmi1->dmi_addrlen) == 0 &&
768 			dmi1->dmi_addrlen == dmi2->dmi_addrlen;
769 }
770 
771 /*
772  * returns dmi entry if found, NULL otherwise
773  */
774 static struct dev_mc_list *bond_mc_list_find_dmi(struct dev_mc_list *dmi, struct dev_mc_list *mc_list)
775 {
776 	struct dev_mc_list *idmi;
777 
778 	for (idmi = mc_list; idmi; idmi = idmi->next) {
779 		if (bond_is_dmi_same(dmi, idmi)) {
780 			return idmi;
781 		}
782 	}
783 
784 	return NULL;
785 }
786 
787 /*
788  * Push the promiscuity flag down to appropriate slaves
789  */
790 static void bond_set_promiscuity(struct bonding *bond, int inc)
791 {
792 	if (USES_PRIMARY(bond->params.mode)) {
793 		/* write lock already acquired */
794 		if (bond->curr_active_slave) {
795 			dev_set_promiscuity(bond->curr_active_slave->dev, inc);
796 		}
797 	} else {
798 		struct slave *slave;
799 		int i;
800 		bond_for_each_slave(bond, slave, i) {
801 			dev_set_promiscuity(slave->dev, inc);
802 		}
803 	}
804 }
805 
806 /*
807  * Push the allmulti flag down to all slaves
808  */
809 static void bond_set_allmulti(struct bonding *bond, int inc)
810 {
811 	if (USES_PRIMARY(bond->params.mode)) {
812 		/* write lock already acquired */
813 		if (bond->curr_active_slave) {
814 			dev_set_allmulti(bond->curr_active_slave->dev, inc);
815 		}
816 	} else {
817 		struct slave *slave;
818 		int i;
819 		bond_for_each_slave(bond, slave, i) {
820 			dev_set_allmulti(slave->dev, inc);
821 		}
822 	}
823 }
824 
825 /*
826  * Add a Multicast address to slaves
827  * according to mode
828  */
829 static void bond_mc_add(struct bonding *bond, void *addr, int alen)
830 {
831 	if (USES_PRIMARY(bond->params.mode)) {
832 		/* write lock already acquired */
833 		if (bond->curr_active_slave) {
834 			dev_mc_add(bond->curr_active_slave->dev, addr, alen, 0);
835 		}
836 	} else {
837 		struct slave *slave;
838 		int i;
839 		bond_for_each_slave(bond, slave, i) {
840 			dev_mc_add(slave->dev, addr, alen, 0);
841 		}
842 	}
843 }
844 
845 /*
846  * Remove a multicast address from slave
847  * according to mode
848  */
849 static void bond_mc_delete(struct bonding *bond, void *addr, int alen)
850 {
851 	if (USES_PRIMARY(bond->params.mode)) {
852 		/* write lock already acquired */
853 		if (bond->curr_active_slave) {
854 			dev_mc_delete(bond->curr_active_slave->dev, addr, alen, 0);
855 		}
856 	} else {
857 		struct slave *slave;
858 		int i;
859 		bond_for_each_slave(bond, slave, i) {
860 			dev_mc_delete(slave->dev, addr, alen, 0);
861 		}
862 	}
863 }
864 
865 /*
866  * Totally destroys the mc_list in bond
867  */
868 static void bond_mc_list_destroy(struct bonding *bond)
869 {
870 	struct dev_mc_list *dmi;
871 
872 	dmi = bond->mc_list;
873 	while (dmi) {
874 		bond->mc_list = dmi->next;
875 		kfree(dmi);
876 		dmi = bond->mc_list;
877 	}
878 }
879 
880 /*
881  * Copy all the Multicast addresses from src to the bonding device dst
882  */
883 static int bond_mc_list_copy(struct dev_mc_list *mc_list, struct bonding *bond,
884 			     gfp_t gfp_flag)
885 {
886 	struct dev_mc_list *dmi, *new_dmi;
887 
888 	for (dmi = mc_list; dmi; dmi = dmi->next) {
889 		new_dmi = kmalloc(sizeof(struct dev_mc_list), gfp_flag);
890 
891 		if (!new_dmi) {
892 			/* FIXME: Potential memory leak !!! */
893 			return -ENOMEM;
894 		}
895 
896 		new_dmi->next = bond->mc_list;
897 		bond->mc_list = new_dmi;
898 		new_dmi->dmi_addrlen = dmi->dmi_addrlen;
899 		memcpy(new_dmi->dmi_addr, dmi->dmi_addr, dmi->dmi_addrlen);
900 		new_dmi->dmi_users = dmi->dmi_users;
901 		new_dmi->dmi_gusers = dmi->dmi_gusers;
902 	}
903 
904 	return 0;
905 }
906 
907 /*
908  * flush all members of flush->mc_list from device dev->mc_list
909  */
910 static void bond_mc_list_flush(struct net_device *bond_dev, struct net_device *slave_dev)
911 {
912 	struct bonding *bond = bond_dev->priv;
913 	struct dev_mc_list *dmi;
914 
915 	for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
916 		dev_mc_delete(slave_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
917 	}
918 
919 	if (bond->params.mode == BOND_MODE_8023AD) {
920 		/* del lacpdu mc addr from mc list */
921 		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
922 
923 		dev_mc_delete(slave_dev, lacpdu_multicast, ETH_ALEN, 0);
924 	}
925 }
926 
927 /*--------------------------- Active slave change ---------------------------*/
928 
929 /*
930  * Update the mc list and multicast-related flags for the new and
931  * old active slaves (if any) according to the multicast mode, and
932  * promiscuous flags unconditionally.
933  */
934 static void bond_mc_swap(struct bonding *bond, struct slave *new_active, struct slave *old_active)
935 {
936 	struct dev_mc_list *dmi;
937 
938 	if (!USES_PRIMARY(bond->params.mode)) {
939 		/* nothing to do -  mc list is already up-to-date on
940 		 * all slaves
941 		 */
942 		return;
943 	}
944 
945 	if (old_active) {
946 		if (bond->dev->flags & IFF_PROMISC) {
947 			dev_set_promiscuity(old_active->dev, -1);
948 		}
949 
950 		if (bond->dev->flags & IFF_ALLMULTI) {
951 			dev_set_allmulti(old_active->dev, -1);
952 		}
953 
954 		for (dmi = bond->dev->mc_list; dmi; dmi = dmi->next) {
955 			dev_mc_delete(old_active->dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
956 		}
957 	}
958 
959 	if (new_active) {
960 		if (bond->dev->flags & IFF_PROMISC) {
961 			dev_set_promiscuity(new_active->dev, 1);
962 		}
963 
964 		if (bond->dev->flags & IFF_ALLMULTI) {
965 			dev_set_allmulti(new_active->dev, 1);
966 		}
967 
968 		for (dmi = bond->dev->mc_list; dmi; dmi = dmi->next) {
969 			dev_mc_add(new_active->dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
970 		}
971 	}
972 }
973 
974 /**
975  * find_best_interface - select the best available slave to be the active one
976  * @bond: our bonding struct
977  *
978  * Warning: Caller must hold curr_slave_lock for writing.
979  */
980 static struct slave *bond_find_best_slave(struct bonding *bond)
981 {
982 	struct slave *new_active, *old_active;
983 	struct slave *bestslave = NULL;
984 	int mintime = bond->params.updelay;
985 	int i;
986 
987 	new_active = old_active = bond->curr_active_slave;
988 
989 	if (!new_active) { /* there were no active slaves left */
990 		if (bond->slave_cnt > 0) {  /* found one slave */
991 			new_active = bond->first_slave;
992 		} else {
993 			return NULL; /* still no slave, return NULL */
994 		}
995 	}
996 
997 	/* first try the primary link; if arping, a link must tx/rx traffic
998 	 * before it can be considered the curr_active_slave - also, we would skip
999 	 * slaves between the curr_active_slave and primary_slave that may be up
1000 	 * and able to arp
1001 	 */
1002 	if ((bond->primary_slave) &&
1003 	    (!bond->params.arp_interval) &&
1004 	    (IS_UP(bond->primary_slave->dev))) {
1005 		new_active = bond->primary_slave;
1006 	}
1007 
1008 	/* remember where to stop iterating over the slaves */
1009 	old_active = new_active;
1010 
1011 	bond_for_each_slave_from(bond, new_active, i, old_active) {
1012 		if (IS_UP(new_active->dev)) {
1013 			if (new_active->link == BOND_LINK_UP) {
1014 				return new_active;
1015 			} else if (new_active->link == BOND_LINK_BACK) {
1016 				/* link up, but waiting for stabilization */
1017 				if (new_active->delay < mintime) {
1018 					mintime = new_active->delay;
1019 					bestslave = new_active;
1020 				}
1021 			}
1022 		}
1023 	}
1024 
1025 	return bestslave;
1026 }
1027 
1028 /**
1029  * change_active_interface - change the active slave into the specified one
1030  * @bond: our bonding struct
1031  * @new: the new slave to make the active one
1032  *
1033  * Set the new slave to the bond's settings and unset them on the old
1034  * curr_active_slave.
1035  * Setting include flags, mc-list, promiscuity, allmulti, etc.
1036  *
1037  * If @new's link state is %BOND_LINK_BACK we'll set it to %BOND_LINK_UP,
1038  * because it is apparently the best available slave we have, even though its
1039  * updelay hasn't timed out yet.
1040  *
1041  * Warning: Caller must hold curr_slave_lock for writing.
1042  */
1043 void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
1044 {
1045 	struct slave *old_active = bond->curr_active_slave;
1046 
1047 	if (old_active == new_active) {
1048 		return;
1049 	}
1050 
1051 	if (new_active) {
1052 		if (new_active->link == BOND_LINK_BACK) {
1053 			if (USES_PRIMARY(bond->params.mode)) {
1054 				printk(KERN_INFO DRV_NAME
1055 				       ": %s: making interface %s the new "
1056 				       "active one %d ms earlier.\n",
1057 				       bond->dev->name, new_active->dev->name,
1058 				       (bond->params.updelay - new_active->delay) * bond->params.miimon);
1059 			}
1060 
1061 			new_active->delay = 0;
1062 			new_active->link = BOND_LINK_UP;
1063 			new_active->jiffies = jiffies;
1064 
1065 			if (bond->params.mode == BOND_MODE_8023AD) {
1066 				bond_3ad_handle_link_change(new_active, BOND_LINK_UP);
1067 			}
1068 
1069 			if ((bond->params.mode == BOND_MODE_TLB) ||
1070 			    (bond->params.mode == BOND_MODE_ALB)) {
1071 				bond_alb_handle_link_change(bond, new_active, BOND_LINK_UP);
1072 			}
1073 		} else {
1074 			if (USES_PRIMARY(bond->params.mode)) {
1075 				printk(KERN_INFO DRV_NAME
1076 				       ": %s: making interface %s the new "
1077 				       "active one.\n",
1078 				       bond->dev->name, new_active->dev->name);
1079 			}
1080 		}
1081 	}
1082 
1083 	if (USES_PRIMARY(bond->params.mode)) {
1084 		bond_mc_swap(bond, new_active, old_active);
1085 	}
1086 
1087 	if ((bond->params.mode == BOND_MODE_TLB) ||
1088 	    (bond->params.mode == BOND_MODE_ALB)) {
1089 		bond_alb_handle_active_change(bond, new_active);
1090 		if (old_active)
1091 			bond_set_slave_inactive_flags(old_active);
1092 		if (new_active)
1093 			bond_set_slave_active_flags(new_active);
1094 	} else {
1095 		bond->curr_active_slave = new_active;
1096 	}
1097 
1098 	if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
1099 		if (old_active) {
1100 			bond_set_slave_inactive_flags(old_active);
1101 		}
1102 
1103 		if (new_active) {
1104 			bond_set_slave_active_flags(new_active);
1105 		}
1106 		bond_send_gratuitous_arp(bond);
1107 	}
1108 }
1109 
1110 /**
1111  * bond_select_active_slave - select a new active slave, if needed
1112  * @bond: our bonding struct
1113  *
1114  * This functions shoud be called when one of the following occurs:
1115  * - The old curr_active_slave has been released or lost its link.
1116  * - The primary_slave has got its link back.
1117  * - A slave has got its link back and there's no old curr_active_slave.
1118  *
1119  * Warning: Caller must hold curr_slave_lock for writing.
1120  */
1121 void bond_select_active_slave(struct bonding *bond)
1122 {
1123 	struct slave *best_slave;
1124 	int rv;
1125 
1126 	best_slave = bond_find_best_slave(bond);
1127 	if (best_slave != bond->curr_active_slave) {
1128 		bond_change_active_slave(bond, best_slave);
1129 		rv = bond_set_carrier(bond);
1130 		if (!rv)
1131 			return;
1132 
1133 		if (netif_carrier_ok(bond->dev)) {
1134 			printk(KERN_INFO DRV_NAME
1135 			       ": %s: first active interface up!\n",
1136 			       bond->dev->name);
1137 		} else {
1138 			printk(KERN_INFO DRV_NAME ": %s: "
1139 			       "now running without any active interface !\n",
1140 			       bond->dev->name);
1141 		}
1142 	}
1143 }
1144 
1145 /*--------------------------- slave list handling ---------------------------*/
1146 
1147 /*
1148  * This function attaches the slave to the end of list.
1149  *
1150  * bond->lock held for writing by caller.
1151  */
1152 static void bond_attach_slave(struct bonding *bond, struct slave *new_slave)
1153 {
1154 	if (bond->first_slave == NULL) { /* attaching the first slave */
1155 		new_slave->next = new_slave;
1156 		new_slave->prev = new_slave;
1157 		bond->first_slave = new_slave;
1158 	} else {
1159 		new_slave->next = bond->first_slave;
1160 		new_slave->prev = bond->first_slave->prev;
1161 		new_slave->next->prev = new_slave;
1162 		new_slave->prev->next = new_slave;
1163 	}
1164 
1165 	bond->slave_cnt++;
1166 }
1167 
1168 /*
1169  * This function detaches the slave from the list.
1170  * WARNING: no check is made to verify if the slave effectively
1171  * belongs to <bond>.
1172  * Nothing is freed on return, structures are just unchained.
1173  * If any slave pointer in bond was pointing to <slave>,
1174  * it should be changed by the calling function.
1175  *
1176  * bond->lock held for writing by caller.
1177  */
1178 static void bond_detach_slave(struct bonding *bond, struct slave *slave)
1179 {
1180 	if (slave->next) {
1181 		slave->next->prev = slave->prev;
1182 	}
1183 
1184 	if (slave->prev) {
1185 		slave->prev->next = slave->next;
1186 	}
1187 
1188 	if (bond->first_slave == slave) { /* slave is the first slave */
1189 		if (bond->slave_cnt > 1) { /* there are more slave */
1190 			bond->first_slave = slave->next;
1191 		} else {
1192 			bond->first_slave = NULL; /* slave was the last one */
1193 		}
1194 	}
1195 
1196 	slave->next = NULL;
1197 	slave->prev = NULL;
1198 	bond->slave_cnt--;
1199 }
1200 
1201 /*---------------------------------- IOCTL ----------------------------------*/
1202 
1203 int bond_sethwaddr(struct net_device *bond_dev, struct net_device *slave_dev)
1204 {
1205 	dprintk("bond_dev=%p\n", bond_dev);
1206 	dprintk("slave_dev=%p\n", slave_dev);
1207 	dprintk("slave_dev->addr_len=%d\n", slave_dev->addr_len);
1208 	memcpy(bond_dev->dev_addr, slave_dev->dev_addr, slave_dev->addr_len);
1209 	return 0;
1210 }
1211 
1212 #define BOND_INTERSECT_FEATURES \
1213 	(NETIF_F_SG | NETIF_F_ALL_CSUM | NETIF_F_TSO | NETIF_F_UFO)
1214 
1215 /*
1216  * Compute the common dev->feature set available to all slaves.  Some
1217  * feature bits are managed elsewhere, so preserve feature bits set on
1218  * master device that are not part of the examined set.
1219  */
1220 static int bond_compute_features(struct bonding *bond)
1221 {
1222 	unsigned long features = BOND_INTERSECT_FEATURES;
1223 	struct slave *slave;
1224 	struct net_device *bond_dev = bond->dev;
1225 	unsigned short max_hard_header_len = ETH_HLEN;
1226 	int i;
1227 
1228 	bond_for_each_slave(bond, slave, i) {
1229 		features &= (slave->dev->features & BOND_INTERSECT_FEATURES);
1230 		if (slave->dev->hard_header_len > max_hard_header_len)
1231 			max_hard_header_len = slave->dev->hard_header_len;
1232 	}
1233 
1234 	if ((features & NETIF_F_SG) &&
1235 	    !(features & NETIF_F_ALL_CSUM))
1236 		features &= ~NETIF_F_SG;
1237 
1238 	/*
1239 	 * features will include NETIF_F_TSO (NETIF_F_UFO) iff all
1240 	 * slave devices support NETIF_F_TSO (NETIF_F_UFO), which
1241 	 * implies that all slaves also support scatter-gather
1242 	 * (NETIF_F_SG), which implies that features also includes
1243 	 * NETIF_F_SG. So no need to check whether we have an
1244 	 * illegal combination of NETIF_F_{TSO,UFO} and
1245 	 * !NETIF_F_SG
1246 	 */
1247 
1248 	features |= (bond_dev->features & ~BOND_INTERSECT_FEATURES);
1249 	bond_dev->features = features;
1250 	bond_dev->hard_header_len = max_hard_header_len;
1251 
1252 	return 0;
1253 }
1254 
1255 /* enslave device <slave> to bond device <master> */
1256 int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
1257 {
1258 	struct bonding *bond = bond_dev->priv;
1259 	struct slave *new_slave = NULL;
1260 	struct dev_mc_list *dmi;
1261 	struct sockaddr addr;
1262 	int link_reporting;
1263 	int old_features = bond_dev->features;
1264 	int res = 0;
1265 
1266 	if (!bond->params.use_carrier && slave_dev->ethtool_ops == NULL &&
1267 		slave_dev->do_ioctl == NULL) {
1268 		printk(KERN_WARNING DRV_NAME
1269 		       ": %s: Warning: no link monitoring support for %s\n",
1270 		       bond_dev->name, slave_dev->name);
1271 	}
1272 
1273 	/* bond must be initialized by bond_open() before enslaving */
1274 	if (!(bond_dev->flags & IFF_UP)) {
1275 		dprintk("Error, master_dev is not up\n");
1276 		return -EPERM;
1277 	}
1278 
1279 	/* already enslaved */
1280 	if (slave_dev->flags & IFF_SLAVE) {
1281 		dprintk("Error, Device was already enslaved\n");
1282 		return -EBUSY;
1283 	}
1284 
1285 	/* vlan challenged mutual exclusion */
1286 	/* no need to lock since we're protected by rtnl_lock */
1287 	if (slave_dev->features & NETIF_F_VLAN_CHALLENGED) {
1288 		dprintk("%s: NETIF_F_VLAN_CHALLENGED\n", slave_dev->name);
1289 		if (!list_empty(&bond->vlan_list)) {
1290 			printk(KERN_ERR DRV_NAME
1291 			       ": %s: Error: cannot enslave VLAN "
1292 			       "challenged slave %s on VLAN enabled "
1293 			       "bond %s\n", bond_dev->name, slave_dev->name,
1294 			       bond_dev->name);
1295 			return -EPERM;
1296 		} else {
1297 			printk(KERN_WARNING DRV_NAME
1298 			       ": %s: Warning: enslaved VLAN challenged "
1299 			       "slave %s. Adding VLANs will be blocked as "
1300 			       "long as %s is part of bond %s\n",
1301 			       bond_dev->name, slave_dev->name, slave_dev->name,
1302 			       bond_dev->name);
1303 			bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
1304 		}
1305 	} else {
1306 		dprintk("%s: ! NETIF_F_VLAN_CHALLENGED\n", slave_dev->name);
1307 		if (bond->slave_cnt == 0) {
1308 			/* First slave, and it is not VLAN challenged,
1309 			 * so remove the block of adding VLANs over the bond.
1310 			 */
1311 			bond_dev->features &= ~NETIF_F_VLAN_CHALLENGED;
1312 		}
1313 	}
1314 
1315 	/*
1316 	 * Old ifenslave binaries are no longer supported.  These can
1317 	 * be identified with moderate accurary by the state of the slave:
1318 	 * the current ifenslave will set the interface down prior to
1319 	 * enslaving it; the old ifenslave will not.
1320 	 */
1321 	if ((slave_dev->flags & IFF_UP)) {
1322 		printk(KERN_ERR DRV_NAME ": %s is up. "
1323 		       "This may be due to an out of date ifenslave.\n",
1324 		       slave_dev->name);
1325 		res = -EPERM;
1326 		goto err_undo_flags;
1327 	}
1328 
1329 	if (slave_dev->set_mac_address == NULL) {
1330 		printk(KERN_ERR DRV_NAME
1331 			": %s: Error: The slave device you specified does "
1332 			"not support setting the MAC address. "
1333 			"Your kernel likely does not support slave "
1334 			"devices.\n", bond_dev->name);
1335   		res = -EOPNOTSUPP;
1336 		goto err_undo_flags;
1337 	}
1338 
1339 	if (slave_dev->get_stats == NULL) {
1340 		printk(KERN_NOTICE DRV_NAME
1341 			": %s: the driver for slave device %s does not provide "
1342 			"get_stats function, network statistics will be "
1343 			"inaccurate.\n", bond_dev->name, slave_dev->name);
1344 	}
1345 
1346 	new_slave = kmalloc(sizeof(struct slave), GFP_KERNEL);
1347 	if (!new_slave) {
1348 		res = -ENOMEM;
1349 		goto err_undo_flags;
1350 	}
1351 
1352 	memset(new_slave, 0, sizeof(struct slave));
1353 
1354 	/* save slave's original flags before calling
1355 	 * netdev_set_master and dev_open
1356 	 */
1357 	new_slave->original_flags = slave_dev->flags;
1358 
1359 	/*
1360 	 * Save slave's original ("permanent") mac address for modes
1361 	 * that need it, and for restoring it upon release, and then
1362 	 * set it to the master's address
1363 	 */
1364 	memcpy(new_slave->perm_hwaddr, slave_dev->dev_addr, ETH_ALEN);
1365 
1366 	/*
1367 	 * Set slave to master's mac address.  The application already
1368 	 * set the master's mac address to that of the first slave
1369 	 */
1370 	memcpy(addr.sa_data, bond_dev->dev_addr, bond_dev->addr_len);
1371 	addr.sa_family = slave_dev->type;
1372 	res = dev_set_mac_address(slave_dev, &addr);
1373 	if (res) {
1374 		dprintk("Error %d calling set_mac_address\n", res);
1375 		goto err_free;
1376 	}
1377 
1378 	/* open the slave since the application closed it */
1379 	res = dev_open(slave_dev);
1380 	if (res) {
1381 		dprintk("Openning slave %s failed\n", slave_dev->name);
1382 		goto err_restore_mac;
1383 	}
1384 
1385 	res = netdev_set_master(slave_dev, bond_dev);
1386 	if (res) {
1387 		dprintk("Error %d calling netdev_set_master\n", res);
1388 		goto err_close;
1389 	}
1390 
1391 	new_slave->dev = slave_dev;
1392 	slave_dev->priv_flags |= IFF_BONDING;
1393 
1394 	if ((bond->params.mode == BOND_MODE_TLB) ||
1395 	    (bond->params.mode == BOND_MODE_ALB)) {
1396 		/* bond_alb_init_slave() must be called before all other stages since
1397 		 * it might fail and we do not want to have to undo everything
1398 		 */
1399 		res = bond_alb_init_slave(bond, new_slave);
1400 		if (res) {
1401 			goto err_unset_master;
1402 		}
1403 	}
1404 
1405 	/* If the mode USES_PRIMARY, then the new slave gets the
1406 	 * master's promisc (and mc) settings only if it becomes the
1407 	 * curr_active_slave, and that is taken care of later when calling
1408 	 * bond_change_active()
1409 	 */
1410 	if (!USES_PRIMARY(bond->params.mode)) {
1411 		/* set promiscuity level to new slave */
1412 		if (bond_dev->flags & IFF_PROMISC) {
1413 			dev_set_promiscuity(slave_dev, 1);
1414 		}
1415 
1416 		/* set allmulti level to new slave */
1417 		if (bond_dev->flags & IFF_ALLMULTI) {
1418 			dev_set_allmulti(slave_dev, 1);
1419 		}
1420 
1421 		/* upload master's mc_list to new slave */
1422 		for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
1423 			dev_mc_add (slave_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
1424 		}
1425 	}
1426 
1427 	if (bond->params.mode == BOND_MODE_8023AD) {
1428 		/* add lacpdu mc addr to mc list */
1429 		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
1430 
1431 		dev_mc_add(slave_dev, lacpdu_multicast, ETH_ALEN, 0);
1432 	}
1433 
1434 	bond_add_vlans_on_slave(bond, slave_dev);
1435 
1436 	write_lock_bh(&bond->lock);
1437 
1438 	bond_attach_slave(bond, new_slave);
1439 
1440 	new_slave->delay = 0;
1441 	new_slave->link_failure_count = 0;
1442 
1443 	bond_compute_features(bond);
1444 
1445 	new_slave->last_arp_rx = jiffies;
1446 
1447 	if (bond->params.miimon && !bond->params.use_carrier) {
1448 		link_reporting = bond_check_dev_link(bond, slave_dev, 1);
1449 
1450 		if ((link_reporting == -1) && !bond->params.arp_interval) {
1451 			/*
1452 			 * miimon is set but a bonded network driver
1453 			 * does not support ETHTOOL/MII and
1454 			 * arp_interval is not set.  Note: if
1455 			 * use_carrier is enabled, we will never go
1456 			 * here (because netif_carrier is always
1457 			 * supported); thus, we don't need to change
1458 			 * the messages for netif_carrier.
1459 			 */
1460 			printk(KERN_WARNING DRV_NAME
1461 			       ": %s: Warning: MII and ETHTOOL support not "
1462 			       "available for interface %s, and "
1463 			       "arp_interval/arp_ip_target module parameters "
1464 			       "not specified, thus bonding will not detect "
1465 			       "link failures! see bonding.txt for details.\n",
1466 			       bond_dev->name, slave_dev->name);
1467 		} else if (link_reporting == -1) {
1468 			/* unable get link status using mii/ethtool */
1469 			printk(KERN_WARNING DRV_NAME
1470 			       ": %s: Warning: can't get link status from "
1471 			       "interface %s; the network driver associated "
1472 			       "with this interface does not support MII or "
1473 			       "ETHTOOL link status reporting, thus miimon "
1474 			       "has no effect on this interface.\n",
1475 			       bond_dev->name, slave_dev->name);
1476 		}
1477 	}
1478 
1479 	/* check for initial state */
1480 	if (!bond->params.miimon ||
1481 	    (bond_check_dev_link(bond, slave_dev, 0) == BMSR_LSTATUS)) {
1482 		if (bond->params.updelay) {
1483 			dprintk("Initial state of slave_dev is "
1484 				"BOND_LINK_BACK\n");
1485 			new_slave->link  = BOND_LINK_BACK;
1486 			new_slave->delay = bond->params.updelay;
1487 		} else {
1488 			dprintk("Initial state of slave_dev is "
1489 				"BOND_LINK_UP\n");
1490 			new_slave->link  = BOND_LINK_UP;
1491 		}
1492 		new_slave->jiffies = jiffies;
1493 	} else {
1494 		dprintk("Initial state of slave_dev is "
1495 			"BOND_LINK_DOWN\n");
1496 		new_slave->link  = BOND_LINK_DOWN;
1497 	}
1498 
1499 	if (bond_update_speed_duplex(new_slave) &&
1500 	    (new_slave->link != BOND_LINK_DOWN)) {
1501 		printk(KERN_WARNING DRV_NAME
1502 		       ": %s: Warning: failed to get speed and duplex from %s, "
1503 		       "assumed to be 100Mb/sec and Full.\n",
1504 		       bond_dev->name, new_slave->dev->name);
1505 
1506 		if (bond->params.mode == BOND_MODE_8023AD) {
1507 			printk(KERN_WARNING DRV_NAME
1508 			       ": %s: Warning: Operation of 802.3ad mode requires ETHTOOL "
1509 			       "support in base driver for proper aggregator "
1510 			       "selection.\n", bond_dev->name);
1511 		}
1512 	}
1513 
1514 	if (USES_PRIMARY(bond->params.mode) && bond->params.primary[0]) {
1515 		/* if there is a primary slave, remember it */
1516 		if (strcmp(bond->params.primary, new_slave->dev->name) == 0) {
1517 			bond->primary_slave = new_slave;
1518 		}
1519 	}
1520 
1521 	switch (bond->params.mode) {
1522 	case BOND_MODE_ACTIVEBACKUP:
1523 		bond_set_slave_inactive_flags(new_slave);
1524 		bond_select_active_slave(bond);
1525 		break;
1526 	case BOND_MODE_8023AD:
1527 		/* in 802.3ad mode, the internal mechanism
1528 		 * will activate the slaves in the selected
1529 		 * aggregator
1530 		 */
1531 		bond_set_slave_inactive_flags(new_slave);
1532 		/* if this is the first slave */
1533 		if (bond->slave_cnt == 1) {
1534 			SLAVE_AD_INFO(new_slave).id = 1;
1535 			/* Initialize AD with the number of times that the AD timer is called in 1 second
1536 			 * can be called only after the mac address of the bond is set
1537 			 */
1538 			bond_3ad_initialize(bond, 1000/AD_TIMER_INTERVAL,
1539 					    bond->params.lacp_fast);
1540 		} else {
1541 			SLAVE_AD_INFO(new_slave).id =
1542 				SLAVE_AD_INFO(new_slave->prev).id + 1;
1543 		}
1544 
1545 		bond_3ad_bind_slave(new_slave);
1546 		break;
1547 	case BOND_MODE_TLB:
1548 	case BOND_MODE_ALB:
1549 		new_slave->state = BOND_STATE_ACTIVE;
1550 		if ((!bond->curr_active_slave) &&
1551 		    (new_slave->link != BOND_LINK_DOWN)) {
1552 			/* first slave or no active slave yet, and this link
1553 			 * is OK, so make this interface the active one
1554 			 */
1555 			bond_change_active_slave(bond, new_slave);
1556 		} else {
1557 			bond_set_slave_inactive_flags(new_slave);
1558 		}
1559 		break;
1560 	default:
1561 		dprintk("This slave is always active in trunk mode\n");
1562 
1563 		/* always active in trunk mode */
1564 		new_slave->state = BOND_STATE_ACTIVE;
1565 
1566 		/* In trunking mode there is little meaning to curr_active_slave
1567 		 * anyway (it holds no special properties of the bond device),
1568 		 * so we can change it without calling change_active_interface()
1569 		 */
1570 		if (!bond->curr_active_slave) {
1571 			bond->curr_active_slave = new_slave;
1572 		}
1573 		break;
1574 	} /* switch(bond_mode) */
1575 
1576 	bond_set_carrier(bond);
1577 
1578 	write_unlock_bh(&bond->lock);
1579 
1580 	res = bond_create_slave_symlinks(bond_dev, slave_dev);
1581 	if (res)
1582 		goto err_unset_master;
1583 
1584 	printk(KERN_INFO DRV_NAME
1585 	       ": %s: enslaving %s as a%s interface with a%s link.\n",
1586 	       bond_dev->name, slave_dev->name,
1587 	       new_slave->state == BOND_STATE_ACTIVE ? "n active" : " backup",
1588 	       new_slave->link != BOND_LINK_DOWN ? "n up" : " down");
1589 
1590 	/* enslave is successful */
1591 	return 0;
1592 
1593 /* Undo stages on error */
1594 err_unset_master:
1595 	netdev_set_master(slave_dev, NULL);
1596 
1597 err_close:
1598 	dev_close(slave_dev);
1599 
1600 err_restore_mac:
1601 	memcpy(addr.sa_data, new_slave->perm_hwaddr, ETH_ALEN);
1602 	addr.sa_family = slave_dev->type;
1603 	dev_set_mac_address(slave_dev, &addr);
1604 
1605 err_free:
1606 	kfree(new_slave);
1607 
1608 err_undo_flags:
1609 	bond_dev->features = old_features;
1610 
1611 	return res;
1612 }
1613 
1614 /*
1615  * Try to release the slave device <slave> from the bond device <master>
1616  * It is legal to access curr_active_slave without a lock because all the function
1617  * is write-locked.
1618  *
1619  * The rules for slave state should be:
1620  *   for Active/Backup:
1621  *     Active stays on all backups go down
1622  *   for Bonded connections:
1623  *     The first up interface should be left on and all others downed.
1624  */
1625 int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
1626 {
1627 	struct bonding *bond = bond_dev->priv;
1628 	struct slave *slave, *oldcurrent;
1629 	struct sockaddr addr;
1630 	int mac_addr_differ;
1631 
1632 	/* slave is not a slave or master is not master of this slave */
1633 	if (!(slave_dev->flags & IFF_SLAVE) ||
1634 	    (slave_dev->master != bond_dev)) {
1635 		printk(KERN_ERR DRV_NAME
1636 		       ": %s: Error: cannot release %s.\n",
1637 		       bond_dev->name, slave_dev->name);
1638 		return -EINVAL;
1639 	}
1640 
1641 	write_lock_bh(&bond->lock);
1642 
1643 	slave = bond_get_slave_by_dev(bond, slave_dev);
1644 	if (!slave) {
1645 		/* not a slave of this bond */
1646 		printk(KERN_INFO DRV_NAME
1647 		       ": %s: %s not enslaved\n",
1648 		       bond_dev->name, slave_dev->name);
1649 		write_unlock_bh(&bond->lock);
1650 		return -EINVAL;
1651 	}
1652 
1653 	mac_addr_differ = memcmp(bond_dev->dev_addr,
1654 				 slave->perm_hwaddr,
1655 				 ETH_ALEN);
1656 	if (!mac_addr_differ && (bond->slave_cnt > 1)) {
1657 		printk(KERN_WARNING DRV_NAME
1658 		       ": %s: Warning: the permanent HWaddr of %s "
1659 		       "- %02X:%02X:%02X:%02X:%02X:%02X - is "
1660 		       "still in use by %s. Set the HWaddr of "
1661 		       "%s to a different address to avoid "
1662 		       "conflicts.\n",
1663 		       bond_dev->name,
1664 		       slave_dev->name,
1665 		       slave->perm_hwaddr[0],
1666 		       slave->perm_hwaddr[1],
1667 		       slave->perm_hwaddr[2],
1668 		       slave->perm_hwaddr[3],
1669 		       slave->perm_hwaddr[4],
1670 		       slave->perm_hwaddr[5],
1671 		       bond_dev->name,
1672 		       slave_dev->name);
1673 	}
1674 
1675 	/* Inform AD package of unbinding of slave. */
1676 	if (bond->params.mode == BOND_MODE_8023AD) {
1677 		/* must be called before the slave is
1678 		 * detached from the list
1679 		 */
1680 		bond_3ad_unbind_slave(slave);
1681 	}
1682 
1683 	printk(KERN_INFO DRV_NAME
1684 	       ": %s: releasing %s interface %s\n",
1685 	       bond_dev->name,
1686 	       (slave->state == BOND_STATE_ACTIVE)
1687 	       ? "active" : "backup",
1688 	       slave_dev->name);
1689 
1690 	oldcurrent = bond->curr_active_slave;
1691 
1692 	bond->current_arp_slave = NULL;
1693 
1694 	/* release the slave from its bond */
1695 	bond_detach_slave(bond, slave);
1696 
1697 	bond_compute_features(bond);
1698 
1699 	if (bond->primary_slave == slave) {
1700 		bond->primary_slave = NULL;
1701 	}
1702 
1703 	if (oldcurrent == slave) {
1704 		bond_change_active_slave(bond, NULL);
1705 	}
1706 
1707 	if ((bond->params.mode == BOND_MODE_TLB) ||
1708 	    (bond->params.mode == BOND_MODE_ALB)) {
1709 		/* Must be called only after the slave has been
1710 		 * detached from the list and the curr_active_slave
1711 		 * has been cleared (if our_slave == old_current),
1712 		 * but before a new active slave is selected.
1713 		 */
1714 		bond_alb_deinit_slave(bond, slave);
1715 	}
1716 
1717 	if (oldcurrent == slave)
1718 		bond_select_active_slave(bond);
1719 
1720 	if (bond->slave_cnt == 0) {
1721 		bond_set_carrier(bond);
1722 
1723 		/* if the last slave was removed, zero the mac address
1724 		 * of the master so it will be set by the application
1725 		 * to the mac address of the first slave
1726 		 */
1727 		memset(bond_dev->dev_addr, 0, bond_dev->addr_len);
1728 
1729 		if (list_empty(&bond->vlan_list)) {
1730 			bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
1731 		} else {
1732 			printk(KERN_WARNING DRV_NAME
1733 			       ": %s: Warning: clearing HW address of %s while it "
1734 			       "still has VLANs.\n",
1735 			       bond_dev->name, bond_dev->name);
1736 			printk(KERN_WARNING DRV_NAME
1737 			       ": %s: When re-adding slaves, make sure the bond's "
1738 			       "HW address matches its VLANs'.\n",
1739 			       bond_dev->name);
1740 		}
1741 	} else if ((bond_dev->features & NETIF_F_VLAN_CHALLENGED) &&
1742 		   !bond_has_challenged_slaves(bond)) {
1743 		printk(KERN_INFO DRV_NAME
1744 		       ": %s: last VLAN challenged slave %s "
1745 		       "left bond %s. VLAN blocking is removed\n",
1746 		       bond_dev->name, slave_dev->name, bond_dev->name);
1747 		bond_dev->features &= ~NETIF_F_VLAN_CHALLENGED;
1748 	}
1749 
1750 	write_unlock_bh(&bond->lock);
1751 
1752 	/* must do this from outside any spinlocks */
1753 	bond_destroy_slave_symlinks(bond_dev, slave_dev);
1754 
1755 	bond_del_vlans_from_slave(bond, slave_dev);
1756 
1757 	/* If the mode USES_PRIMARY, then we should only remove its
1758 	 * promisc and mc settings if it was the curr_active_slave, but that was
1759 	 * already taken care of above when we detached the slave
1760 	 */
1761 	if (!USES_PRIMARY(bond->params.mode)) {
1762 		/* unset promiscuity level from slave */
1763 		if (bond_dev->flags & IFF_PROMISC) {
1764 			dev_set_promiscuity(slave_dev, -1);
1765 		}
1766 
1767 		/* unset allmulti level from slave */
1768 		if (bond_dev->flags & IFF_ALLMULTI) {
1769 			dev_set_allmulti(slave_dev, -1);
1770 		}
1771 
1772 		/* flush master's mc_list from slave */
1773 		bond_mc_list_flush(bond_dev, slave_dev);
1774 	}
1775 
1776 	netdev_set_master(slave_dev, NULL);
1777 
1778 	/* close slave before restoring its mac address */
1779 	dev_close(slave_dev);
1780 
1781 	/* restore original ("permanent") mac address */
1782 	memcpy(addr.sa_data, slave->perm_hwaddr, ETH_ALEN);
1783 	addr.sa_family = slave_dev->type;
1784 	dev_set_mac_address(slave_dev, &addr);
1785 
1786 	slave_dev->priv_flags &= ~(IFF_MASTER_8023AD | IFF_MASTER_ALB |
1787 				   IFF_SLAVE_INACTIVE | IFF_BONDING |
1788 				   IFF_SLAVE_NEEDARP);
1789 
1790 	kfree(slave);
1791 
1792 	return 0;  /* deletion OK */
1793 }
1794 
1795 /*
1796  * This function releases all slaves.
1797  */
1798 static int bond_release_all(struct net_device *bond_dev)
1799 {
1800 	struct bonding *bond = bond_dev->priv;
1801 	struct slave *slave;
1802 	struct net_device *slave_dev;
1803 	struct sockaddr addr;
1804 
1805 	write_lock_bh(&bond->lock);
1806 
1807 	netif_carrier_off(bond_dev);
1808 
1809 	if (bond->slave_cnt == 0) {
1810 		goto out;
1811 	}
1812 
1813 	bond->current_arp_slave = NULL;
1814 	bond->primary_slave = NULL;
1815 	bond_change_active_slave(bond, NULL);
1816 
1817 	while ((slave = bond->first_slave) != NULL) {
1818 		/* Inform AD package of unbinding of slave
1819 		 * before slave is detached from the list.
1820 		 */
1821 		if (bond->params.mode == BOND_MODE_8023AD) {
1822 			bond_3ad_unbind_slave(slave);
1823 		}
1824 
1825 		slave_dev = slave->dev;
1826 		bond_detach_slave(bond, slave);
1827 
1828 		if ((bond->params.mode == BOND_MODE_TLB) ||
1829 		    (bond->params.mode == BOND_MODE_ALB)) {
1830 			/* must be called only after the slave
1831 			 * has been detached from the list
1832 			 */
1833 			bond_alb_deinit_slave(bond, slave);
1834 		}
1835 
1836 		bond_compute_features(bond);
1837 
1838 		/* now that the slave is detached, unlock and perform
1839 		 * all the undo steps that should not be called from
1840 		 * within a lock.
1841 		 */
1842 		write_unlock_bh(&bond->lock);
1843 
1844 		bond_destroy_slave_symlinks(bond_dev, slave_dev);
1845 		bond_del_vlans_from_slave(bond, slave_dev);
1846 
1847 		/* If the mode USES_PRIMARY, then we should only remove its
1848 		 * promisc and mc settings if it was the curr_active_slave, but that was
1849 		 * already taken care of above when we detached the slave
1850 		 */
1851 		if (!USES_PRIMARY(bond->params.mode)) {
1852 			/* unset promiscuity level from slave */
1853 			if (bond_dev->flags & IFF_PROMISC) {
1854 				dev_set_promiscuity(slave_dev, -1);
1855 			}
1856 
1857 			/* unset allmulti level from slave */
1858 			if (bond_dev->flags & IFF_ALLMULTI) {
1859 				dev_set_allmulti(slave_dev, -1);
1860 			}
1861 
1862 			/* flush master's mc_list from slave */
1863 			bond_mc_list_flush(bond_dev, slave_dev);
1864 		}
1865 
1866 		netdev_set_master(slave_dev, NULL);
1867 
1868 		/* close slave before restoring its mac address */
1869 		dev_close(slave_dev);
1870 
1871 		/* restore original ("permanent") mac address*/
1872 		memcpy(addr.sa_data, slave->perm_hwaddr, ETH_ALEN);
1873 		addr.sa_family = slave_dev->type;
1874 		dev_set_mac_address(slave_dev, &addr);
1875 
1876 		slave_dev->priv_flags &= ~(IFF_MASTER_8023AD | IFF_MASTER_ALB |
1877 					   IFF_SLAVE_INACTIVE);
1878 
1879 		kfree(slave);
1880 
1881 		/* re-acquire the lock before getting the next slave */
1882 		write_lock_bh(&bond->lock);
1883 	}
1884 
1885 	/* zero the mac address of the master so it will be
1886 	 * set by the application to the mac address of the
1887 	 * first slave
1888 	 */
1889 	memset(bond_dev->dev_addr, 0, bond_dev->addr_len);
1890 
1891 	if (list_empty(&bond->vlan_list)) {
1892 		bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
1893 	} else {
1894 		printk(KERN_WARNING DRV_NAME
1895 		       ": %s: Warning: clearing HW address of %s while it "
1896 		       "still has VLANs.\n",
1897 		       bond_dev->name, bond_dev->name);
1898 		printk(KERN_WARNING DRV_NAME
1899 		       ": %s: When re-adding slaves, make sure the bond's "
1900 		       "HW address matches its VLANs'.\n",
1901 		       bond_dev->name);
1902 	}
1903 
1904 	printk(KERN_INFO DRV_NAME
1905 	       ": %s: released all slaves\n",
1906 	       bond_dev->name);
1907 
1908 out:
1909 	write_unlock_bh(&bond->lock);
1910 
1911 	return 0;
1912 }
1913 
1914 /*
1915  * This function changes the active slave to slave <slave_dev>.
1916  * It returns -EINVAL in the following cases.
1917  *  - <slave_dev> is not found in the list.
1918  *  - There is not active slave now.
1919  *  - <slave_dev> is already active.
1920  *  - The link state of <slave_dev> is not BOND_LINK_UP.
1921  *  - <slave_dev> is not running.
1922  * In these cases, this fuction does nothing.
1923  * In the other cases, currnt_slave pointer is changed and 0 is returned.
1924  */
1925 static int bond_ioctl_change_active(struct net_device *bond_dev, struct net_device *slave_dev)
1926 {
1927 	struct bonding *bond = bond_dev->priv;
1928 	struct slave *old_active = NULL;
1929 	struct slave *new_active = NULL;
1930 	int res = 0;
1931 
1932 	if (!USES_PRIMARY(bond->params.mode)) {
1933 		return -EINVAL;
1934 	}
1935 
1936 	/* Verify that master_dev is indeed the master of slave_dev */
1937 	if (!(slave_dev->flags & IFF_SLAVE) ||
1938 	    (slave_dev->master != bond_dev)) {
1939 		return -EINVAL;
1940 	}
1941 
1942 	write_lock_bh(&bond->lock);
1943 
1944 	old_active = bond->curr_active_slave;
1945 	new_active = bond_get_slave_by_dev(bond, slave_dev);
1946 
1947 	/*
1948 	 * Changing to the current active: do nothing; return success.
1949 	 */
1950 	if (new_active && (new_active == old_active)) {
1951 		write_unlock_bh(&bond->lock);
1952 		return 0;
1953 	}
1954 
1955 	if ((new_active) &&
1956 	    (old_active) &&
1957 	    (new_active->link == BOND_LINK_UP) &&
1958 	    IS_UP(new_active->dev)) {
1959 		bond_change_active_slave(bond, new_active);
1960 	} else {
1961 		res = -EINVAL;
1962 	}
1963 
1964 	write_unlock_bh(&bond->lock);
1965 
1966 	return res;
1967 }
1968 
1969 static int bond_info_query(struct net_device *bond_dev, struct ifbond *info)
1970 {
1971 	struct bonding *bond = bond_dev->priv;
1972 
1973 	info->bond_mode = bond->params.mode;
1974 	info->miimon = bond->params.miimon;
1975 
1976 	read_lock_bh(&bond->lock);
1977 	info->num_slaves = bond->slave_cnt;
1978 	read_unlock_bh(&bond->lock);
1979 
1980 	return 0;
1981 }
1982 
1983 static int bond_slave_info_query(struct net_device *bond_dev, struct ifslave *info)
1984 {
1985 	struct bonding *bond = bond_dev->priv;
1986 	struct slave *slave;
1987 	int i, found = 0;
1988 
1989 	if (info->slave_id < 0) {
1990 		return -ENODEV;
1991 	}
1992 
1993 	read_lock_bh(&bond->lock);
1994 
1995 	bond_for_each_slave(bond, slave, i) {
1996 		if (i == (int)info->slave_id) {
1997 			found = 1;
1998 			break;
1999 		}
2000 	}
2001 
2002 	read_unlock_bh(&bond->lock);
2003 
2004 	if (found) {
2005 		strcpy(info->slave_name, slave->dev->name);
2006 		info->link = slave->link;
2007 		info->state = slave->state;
2008 		info->link_failure_count = slave->link_failure_count;
2009 	} else {
2010 		return -ENODEV;
2011 	}
2012 
2013 	return 0;
2014 }
2015 
2016 /*-------------------------------- Monitoring -------------------------------*/
2017 
2018 /* this function is called regularly to monitor each slave's link. */
2019 void bond_mii_monitor(struct net_device *bond_dev)
2020 {
2021 	struct bonding *bond = bond_dev->priv;
2022 	struct slave *slave, *oldcurrent;
2023 	int do_failover = 0;
2024 	int delta_in_ticks;
2025 	int i;
2026 
2027 	read_lock(&bond->lock);
2028 
2029 	delta_in_ticks = (bond->params.miimon * HZ) / 1000;
2030 
2031 	if (bond->kill_timers) {
2032 		goto out;
2033 	}
2034 
2035 	if (bond->slave_cnt == 0) {
2036 		goto re_arm;
2037 	}
2038 
2039 	/* we will try to read the link status of each of our slaves, and
2040 	 * set their IFF_RUNNING flag appropriately. For each slave not
2041 	 * supporting MII status, we won't do anything so that a user-space
2042 	 * program could monitor the link itself if needed.
2043 	 */
2044 
2045 	read_lock(&bond->curr_slave_lock);
2046 	oldcurrent = bond->curr_active_slave;
2047 	read_unlock(&bond->curr_slave_lock);
2048 
2049 	bond_for_each_slave(bond, slave, i) {
2050 		struct net_device *slave_dev = slave->dev;
2051 		int link_state;
2052 		u16 old_speed = slave->speed;
2053 		u8 old_duplex = slave->duplex;
2054 
2055 		link_state = bond_check_dev_link(bond, slave_dev, 0);
2056 
2057 		switch (slave->link) {
2058 		case BOND_LINK_UP:	/* the link was up */
2059 			if (link_state == BMSR_LSTATUS) {
2060 				/* link stays up, nothing more to do */
2061 				break;
2062 			} else { /* link going down */
2063 				slave->link  = BOND_LINK_FAIL;
2064 				slave->delay = bond->params.downdelay;
2065 
2066 				if (slave->link_failure_count < UINT_MAX) {
2067 					slave->link_failure_count++;
2068 				}
2069 
2070 				if (bond->params.downdelay) {
2071 					printk(KERN_INFO DRV_NAME
2072 					       ": %s: link status down for %s "
2073 					       "interface %s, disabling it in "
2074 					       "%d ms.\n",
2075 					       bond_dev->name,
2076 					       IS_UP(slave_dev)
2077 					       ? ((bond->params.mode == BOND_MODE_ACTIVEBACKUP)
2078 						  ? ((slave == oldcurrent)
2079 						     ? "active " : "backup ")
2080 						  : "")
2081 					       : "idle ",
2082 					       slave_dev->name,
2083 					       bond->params.downdelay * bond->params.miimon);
2084 				}
2085 			}
2086 			/* no break ! fall through the BOND_LINK_FAIL test to
2087 			   ensure proper action to be taken
2088 			*/
2089 		case BOND_LINK_FAIL:	/* the link has just gone down */
2090 			if (link_state != BMSR_LSTATUS) {
2091 				/* link stays down */
2092 				if (slave->delay <= 0) {
2093 					/* link down for too long time */
2094 					slave->link = BOND_LINK_DOWN;
2095 
2096 					/* in active/backup mode, we must
2097 					 * completely disable this interface
2098 					 */
2099 					if ((bond->params.mode == BOND_MODE_ACTIVEBACKUP) ||
2100 					    (bond->params.mode == BOND_MODE_8023AD)) {
2101 						bond_set_slave_inactive_flags(slave);
2102 					}
2103 
2104 					printk(KERN_INFO DRV_NAME
2105 					       ": %s: link status definitely "
2106 					       "down for interface %s, "
2107 					       "disabling it\n",
2108 					       bond_dev->name,
2109 					       slave_dev->name);
2110 
2111 					/* notify ad that the link status has changed */
2112 					if (bond->params.mode == BOND_MODE_8023AD) {
2113 						bond_3ad_handle_link_change(slave, BOND_LINK_DOWN);
2114 					}
2115 
2116 					if ((bond->params.mode == BOND_MODE_TLB) ||
2117 					    (bond->params.mode == BOND_MODE_ALB)) {
2118 						bond_alb_handle_link_change(bond, slave, BOND_LINK_DOWN);
2119 					}
2120 
2121 					if (slave == oldcurrent) {
2122 						do_failover = 1;
2123 					}
2124 				} else {
2125 					slave->delay--;
2126 				}
2127 			} else {
2128 				/* link up again */
2129 				slave->link  = BOND_LINK_UP;
2130 				slave->jiffies = jiffies;
2131 				printk(KERN_INFO DRV_NAME
2132 				       ": %s: link status up again after %d "
2133 				       "ms for interface %s.\n",
2134 				       bond_dev->name,
2135 				       (bond->params.downdelay - slave->delay) * bond->params.miimon,
2136 				       slave_dev->name);
2137 			}
2138 			break;
2139 		case BOND_LINK_DOWN:	/* the link was down */
2140 			if (link_state != BMSR_LSTATUS) {
2141 				/* the link stays down, nothing more to do */
2142 				break;
2143 			} else {	/* link going up */
2144 				slave->link  = BOND_LINK_BACK;
2145 				slave->delay = bond->params.updelay;
2146 
2147 				if (bond->params.updelay) {
2148 					/* if updelay == 0, no need to
2149 					   advertise about a 0 ms delay */
2150 					printk(KERN_INFO DRV_NAME
2151 					       ": %s: link status up for "
2152 					       "interface %s, enabling it "
2153 					       "in %d ms.\n",
2154 					       bond_dev->name,
2155 					       slave_dev->name,
2156 					       bond->params.updelay * bond->params.miimon);
2157 				}
2158 			}
2159 			/* no break ! fall through the BOND_LINK_BACK state in
2160 			   case there's something to do.
2161 			*/
2162 		case BOND_LINK_BACK:	/* the link has just come back */
2163 			if (link_state != BMSR_LSTATUS) {
2164 				/* link down again */
2165 				slave->link  = BOND_LINK_DOWN;
2166 
2167 				printk(KERN_INFO DRV_NAME
2168 				       ": %s: link status down again after %d "
2169 				       "ms for interface %s.\n",
2170 				       bond_dev->name,
2171 				       (bond->params.updelay - slave->delay) * bond->params.miimon,
2172 				       slave_dev->name);
2173 			} else {
2174 				/* link stays up */
2175 				if (slave->delay == 0) {
2176 					/* now the link has been up for long time enough */
2177 					slave->link = BOND_LINK_UP;
2178 					slave->jiffies = jiffies;
2179 
2180 					if (bond->params.mode == BOND_MODE_8023AD) {
2181 						/* prevent it from being the active one */
2182 						slave->state = BOND_STATE_BACKUP;
2183 					} else if (bond->params.mode != BOND_MODE_ACTIVEBACKUP) {
2184 						/* make it immediately active */
2185 						slave->state = BOND_STATE_ACTIVE;
2186 					} else if (slave != bond->primary_slave) {
2187 						/* prevent it from being the active one */
2188 						slave->state = BOND_STATE_BACKUP;
2189 					}
2190 
2191 					printk(KERN_INFO DRV_NAME
2192 					       ": %s: link status definitely "
2193 					       "up for interface %s.\n",
2194 					       bond_dev->name,
2195 					       slave_dev->name);
2196 
2197 					/* notify ad that the link status has changed */
2198 					if (bond->params.mode == BOND_MODE_8023AD) {
2199 						bond_3ad_handle_link_change(slave, BOND_LINK_UP);
2200 					}
2201 
2202 					if ((bond->params.mode == BOND_MODE_TLB) ||
2203 					    (bond->params.mode == BOND_MODE_ALB)) {
2204 						bond_alb_handle_link_change(bond, slave, BOND_LINK_UP);
2205 					}
2206 
2207 					if ((!oldcurrent) ||
2208 					    (slave == bond->primary_slave)) {
2209 						do_failover = 1;
2210 					}
2211 				} else {
2212 					slave->delay--;
2213 				}
2214 			}
2215 			break;
2216 		default:
2217 			/* Should not happen */
2218 			printk(KERN_ERR DRV_NAME
2219 			       ": %s: Error: %s Illegal value (link=%d)\n",
2220 			       bond_dev->name,
2221 			       slave->dev->name,
2222 			       slave->link);
2223 			goto out;
2224 		} /* end of switch (slave->link) */
2225 
2226 		bond_update_speed_duplex(slave);
2227 
2228 		if (bond->params.mode == BOND_MODE_8023AD) {
2229 			if (old_speed != slave->speed) {
2230 				bond_3ad_adapter_speed_changed(slave);
2231 			}
2232 
2233 			if (old_duplex != slave->duplex) {
2234 				bond_3ad_adapter_duplex_changed(slave);
2235 			}
2236 		}
2237 
2238 	} /* end of for */
2239 
2240 	if (do_failover) {
2241 		write_lock(&bond->curr_slave_lock);
2242 
2243 		bond_select_active_slave(bond);
2244 
2245 		write_unlock(&bond->curr_slave_lock);
2246 	} else
2247 		bond_set_carrier(bond);
2248 
2249 re_arm:
2250 	if (bond->params.miimon) {
2251 		mod_timer(&bond->mii_timer, jiffies + delta_in_ticks);
2252 	}
2253 out:
2254 	read_unlock(&bond->lock);
2255 }
2256 
2257 
2258 static u32 bond_glean_dev_ip(struct net_device *dev)
2259 {
2260 	struct in_device *idev;
2261 	struct in_ifaddr *ifa;
2262 	__be32 addr = 0;
2263 
2264 	if (!dev)
2265 		return 0;
2266 
2267 	rcu_read_lock();
2268 	idev = __in_dev_get_rcu(dev);
2269 	if (!idev)
2270 		goto out;
2271 
2272 	ifa = idev->ifa_list;
2273 	if (!ifa)
2274 		goto out;
2275 
2276 	addr = ifa->ifa_local;
2277 out:
2278 	rcu_read_unlock();
2279 	return addr;
2280 }
2281 
2282 static int bond_has_ip(struct bonding *bond)
2283 {
2284 	struct vlan_entry *vlan, *vlan_next;
2285 
2286 	if (bond->master_ip)
2287 		return 1;
2288 
2289 	if (list_empty(&bond->vlan_list))
2290 		return 0;
2291 
2292 	list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
2293 				 vlan_list) {
2294 		if (vlan->vlan_ip)
2295 			return 1;
2296 	}
2297 
2298 	return 0;
2299 }
2300 
2301 static int bond_has_this_ip(struct bonding *bond, u32 ip)
2302 {
2303 	struct vlan_entry *vlan, *vlan_next;
2304 
2305 	if (ip == bond->master_ip)
2306 		return 1;
2307 
2308 	if (list_empty(&bond->vlan_list))
2309 		return 0;
2310 
2311 	list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
2312 				 vlan_list) {
2313 		if (ip == vlan->vlan_ip)
2314 			return 1;
2315 	}
2316 
2317 	return 0;
2318 }
2319 
2320 /*
2321  * We go to the (large) trouble of VLAN tagging ARP frames because
2322  * switches in VLAN mode (especially if ports are configured as
2323  * "native" to a VLAN) might not pass non-tagged frames.
2324  */
2325 static void bond_arp_send(struct net_device *slave_dev, int arp_op, u32 dest_ip, u32 src_ip, unsigned short vlan_id)
2326 {
2327 	struct sk_buff *skb;
2328 
2329 	dprintk("arp %d on slave %s: dst %x src %x vid %d\n", arp_op,
2330 	       slave_dev->name, dest_ip, src_ip, vlan_id);
2331 
2332 	skb = arp_create(arp_op, ETH_P_ARP, dest_ip, slave_dev, src_ip,
2333 			 NULL, slave_dev->dev_addr, NULL);
2334 
2335 	if (!skb) {
2336 		printk(KERN_ERR DRV_NAME ": ARP packet allocation failed\n");
2337 		return;
2338 	}
2339 	if (vlan_id) {
2340 		skb = vlan_put_tag(skb, vlan_id);
2341 		if (!skb) {
2342 			printk(KERN_ERR DRV_NAME ": failed to insert VLAN tag\n");
2343 			return;
2344 		}
2345 	}
2346 	arp_xmit(skb);
2347 }
2348 
2349 
2350 static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
2351 {
2352 	int i, vlan_id, rv;
2353 	u32 *targets = bond->params.arp_targets;
2354 	struct vlan_entry *vlan, *vlan_next;
2355 	struct net_device *vlan_dev;
2356 	struct flowi fl;
2357 	struct rtable *rt;
2358 
2359 	for (i = 0; (i < BOND_MAX_ARP_TARGETS); i++) {
2360 		if (!targets[i])
2361 			continue;
2362 		dprintk("basa: target %x\n", targets[i]);
2363 		if (list_empty(&bond->vlan_list)) {
2364 			dprintk("basa: empty vlan: arp_send\n");
2365 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2366 				      bond->master_ip, 0);
2367 			continue;
2368 		}
2369 
2370 		/*
2371 		 * If VLANs are configured, we do a route lookup to
2372 		 * determine which VLAN interface would be used, so we
2373 		 * can tag the ARP with the proper VLAN tag.
2374 		 */
2375 		memset(&fl, 0, sizeof(fl));
2376 		fl.fl4_dst = targets[i];
2377 		fl.fl4_tos = RTO_ONLINK;
2378 
2379 		rv = ip_route_output_key(&rt, &fl);
2380 		if (rv) {
2381 			if (net_ratelimit()) {
2382 				printk(KERN_WARNING DRV_NAME
2383 			     ": %s: no route to arp_ip_target %u.%u.%u.%u\n",
2384 				       bond->dev->name, NIPQUAD(fl.fl4_dst));
2385 			}
2386 			continue;
2387 		}
2388 
2389 		/*
2390 		 * This target is not on a VLAN
2391 		 */
2392 		if (rt->u.dst.dev == bond->dev) {
2393 			ip_rt_put(rt);
2394 			dprintk("basa: rtdev == bond->dev: arp_send\n");
2395 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2396 				      bond->master_ip, 0);
2397 			continue;
2398 		}
2399 
2400 		vlan_id = 0;
2401 		list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
2402 					 vlan_list) {
2403 			vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
2404 			if (vlan_dev == rt->u.dst.dev) {
2405 				vlan_id = vlan->vlan_id;
2406 				dprintk("basa: vlan match on %s %d\n",
2407 				       vlan_dev->name, vlan_id);
2408 				break;
2409 			}
2410 		}
2411 
2412 		if (vlan_id) {
2413 			ip_rt_put(rt);
2414 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2415 				      vlan->vlan_ip, vlan_id);
2416 			continue;
2417 		}
2418 
2419 		if (net_ratelimit()) {
2420 			printk(KERN_WARNING DRV_NAME
2421 	       ": %s: no path to arp_ip_target %u.%u.%u.%u via rt.dev %s\n",
2422 			       bond->dev->name, NIPQUAD(fl.fl4_dst),
2423 			       rt->u.dst.dev ? rt->u.dst.dev->name : "NULL");
2424 		}
2425 		ip_rt_put(rt);
2426 	}
2427 }
2428 
2429 /*
2430  * Kick out a gratuitous ARP for an IP on the bonding master plus one
2431  * for each VLAN above us.
2432  */
2433 static void bond_send_gratuitous_arp(struct bonding *bond)
2434 {
2435 	struct slave *slave = bond->curr_active_slave;
2436 	struct vlan_entry *vlan;
2437 	struct net_device *vlan_dev;
2438 
2439 	dprintk("bond_send_grat_arp: bond %s slave %s\n", bond->dev->name,
2440 				slave ? slave->dev->name : "NULL");
2441 	if (!slave)
2442 		return;
2443 
2444 	if (bond->master_ip) {
2445 		bond_arp_send(slave->dev, ARPOP_REPLY, bond->master_ip,
2446 				  bond->master_ip, 0);
2447 	}
2448 
2449 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
2450 		vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
2451 		if (vlan->vlan_ip) {
2452 			bond_arp_send(slave->dev, ARPOP_REPLY, vlan->vlan_ip,
2453 				      vlan->vlan_ip, vlan->vlan_id);
2454 		}
2455 	}
2456 }
2457 
2458 static void bond_validate_arp(struct bonding *bond, struct slave *slave, u32 sip, u32 tip)
2459 {
2460 	int i;
2461 	u32 *targets = bond->params.arp_targets;
2462 
2463 	targets = bond->params.arp_targets;
2464 	for (i = 0; (i < BOND_MAX_ARP_TARGETS) && targets[i]; i++) {
2465 		dprintk("bva: sip %u.%u.%u.%u tip %u.%u.%u.%u t[%d] "
2466 			"%u.%u.%u.%u bhti(tip) %d\n",
2467 		       NIPQUAD(sip), NIPQUAD(tip), i, NIPQUAD(targets[i]),
2468 		       bond_has_this_ip(bond, tip));
2469 		if (sip == targets[i]) {
2470 			if (bond_has_this_ip(bond, tip))
2471 				slave->last_arp_rx = jiffies;
2472 			return;
2473 		}
2474 	}
2475 }
2476 
2477 static int bond_arp_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
2478 {
2479 	struct arphdr *arp;
2480 	struct slave *slave;
2481 	struct bonding *bond;
2482 	unsigned char *arp_ptr;
2483 	u32 sip, tip;
2484 
2485 	if (!(dev->priv_flags & IFF_BONDING) || !(dev->flags & IFF_MASTER))
2486 		goto out;
2487 
2488 	bond = dev->priv;
2489 	read_lock(&bond->lock);
2490 
2491 	dprintk("bond_arp_rcv: bond %s skb->dev %s orig_dev %s\n",
2492 		bond->dev->name, skb->dev ? skb->dev->name : "NULL",
2493 		orig_dev ? orig_dev->name : "NULL");
2494 
2495 	slave = bond_get_slave_by_dev(bond, orig_dev);
2496 	if (!slave || !slave_do_arp_validate(bond, slave))
2497 		goto out_unlock;
2498 
2499 	/* ARP header, plus 2 device addresses, plus 2 IP addresses.  */
2500 	if (!pskb_may_pull(skb, (sizeof(struct arphdr) +
2501 				 (2 * dev->addr_len) +
2502 				 (2 * sizeof(u32)))))
2503 		goto out_unlock;
2504 
2505 	arp = skb->nh.arph;
2506 	if (arp->ar_hln != dev->addr_len ||
2507 	    skb->pkt_type == PACKET_OTHERHOST ||
2508 	    skb->pkt_type == PACKET_LOOPBACK ||
2509 	    arp->ar_hrd != htons(ARPHRD_ETHER) ||
2510 	    arp->ar_pro != htons(ETH_P_IP) ||
2511 	    arp->ar_pln != 4)
2512 		goto out_unlock;
2513 
2514 	arp_ptr = (unsigned char *)(arp + 1);
2515 	arp_ptr += dev->addr_len;
2516 	memcpy(&sip, arp_ptr, 4);
2517 	arp_ptr += 4 + dev->addr_len;
2518 	memcpy(&tip, arp_ptr, 4);
2519 
2520 	dprintk("bond_arp_rcv: %s %s/%d av %d sv %d sip %u.%u.%u.%u"
2521 		" tip %u.%u.%u.%u\n", bond->dev->name, slave->dev->name,
2522 		slave->state, bond->params.arp_validate,
2523 		slave_do_arp_validate(bond, slave), NIPQUAD(sip), NIPQUAD(tip));
2524 
2525 	/*
2526 	 * Backup slaves won't see the ARP reply, but do come through
2527 	 * here for each ARP probe (so we swap the sip/tip to validate
2528 	 * the probe).  In a "redundant switch, common router" type of
2529 	 * configuration, the ARP probe will (hopefully) travel from
2530 	 * the active, through one switch, the router, then the other
2531 	 * switch before reaching the backup.
2532 	 */
2533 	if (slave->state == BOND_STATE_ACTIVE)
2534 		bond_validate_arp(bond, slave, sip, tip);
2535 	else
2536 		bond_validate_arp(bond, slave, tip, sip);
2537 
2538 out_unlock:
2539 	read_unlock(&bond->lock);
2540 out:
2541 	dev_kfree_skb(skb);
2542 	return NET_RX_SUCCESS;
2543 }
2544 
2545 /*
2546  * this function is called regularly to monitor each slave's link
2547  * ensuring that traffic is being sent and received when arp monitoring
2548  * is used in load-balancing mode. if the adapter has been dormant, then an
2549  * arp is transmitted to generate traffic. see activebackup_arp_monitor for
2550  * arp monitoring in active backup mode.
2551  */
2552 void bond_loadbalance_arp_mon(struct net_device *bond_dev)
2553 {
2554 	struct bonding *bond = bond_dev->priv;
2555 	struct slave *slave, *oldcurrent;
2556 	int do_failover = 0;
2557 	int delta_in_ticks;
2558 	int i;
2559 
2560 	read_lock(&bond->lock);
2561 
2562 	delta_in_ticks = (bond->params.arp_interval * HZ) / 1000;
2563 
2564 	if (bond->kill_timers) {
2565 		goto out;
2566 	}
2567 
2568 	if (bond->slave_cnt == 0) {
2569 		goto re_arm;
2570 	}
2571 
2572 	read_lock(&bond->curr_slave_lock);
2573 	oldcurrent = bond->curr_active_slave;
2574 	read_unlock(&bond->curr_slave_lock);
2575 
2576 	/* see if any of the previous devices are up now (i.e. they have
2577 	 * xmt and rcv traffic). the curr_active_slave does not come into
2578 	 * the picture unless it is null. also, slave->jiffies is not needed
2579 	 * here because we send an arp on each slave and give a slave as
2580 	 * long as it needs to get the tx/rx within the delta.
2581 	 * TODO: what about up/down delay in arp mode? it wasn't here before
2582 	 *       so it can wait
2583 	 */
2584 	bond_for_each_slave(bond, slave, i) {
2585 		if (slave->link != BOND_LINK_UP) {
2586 			if (((jiffies - slave->dev->trans_start) <= delta_in_ticks) &&
2587 			    ((jiffies - slave->dev->last_rx) <= delta_in_ticks)) {
2588 
2589 				slave->link  = BOND_LINK_UP;
2590 				slave->state = BOND_STATE_ACTIVE;
2591 
2592 				/* primary_slave has no meaning in round-robin
2593 				 * mode. the window of a slave being up and
2594 				 * curr_active_slave being null after enslaving
2595 				 * is closed.
2596 				 */
2597 				if (!oldcurrent) {
2598 					printk(KERN_INFO DRV_NAME
2599 					       ": %s: link status definitely "
2600 					       "up for interface %s, ",
2601 					       bond_dev->name,
2602 					       slave->dev->name);
2603 					do_failover = 1;
2604 				} else {
2605 					printk(KERN_INFO DRV_NAME
2606 					       ": %s: interface %s is now up\n",
2607 					       bond_dev->name,
2608 					       slave->dev->name);
2609 				}
2610 			}
2611 		} else {
2612 			/* slave->link == BOND_LINK_UP */
2613 
2614 			/* not all switches will respond to an arp request
2615 			 * when the source ip is 0, so don't take the link down
2616 			 * if we don't know our ip yet
2617 			 */
2618 			if (((jiffies - slave->dev->trans_start) >= (2*delta_in_ticks)) ||
2619 			    (((jiffies - slave->dev->last_rx) >= (2*delta_in_ticks)) &&
2620 			     bond_has_ip(bond))) {
2621 
2622 				slave->link  = BOND_LINK_DOWN;
2623 				slave->state = BOND_STATE_BACKUP;
2624 
2625 				if (slave->link_failure_count < UINT_MAX) {
2626 					slave->link_failure_count++;
2627 				}
2628 
2629 				printk(KERN_INFO DRV_NAME
2630 				       ": %s: interface %s is now down.\n",
2631 				       bond_dev->name,
2632 				       slave->dev->name);
2633 
2634 				if (slave == oldcurrent) {
2635 					do_failover = 1;
2636 				}
2637 			}
2638 		}
2639 
2640 		/* note: if switch is in round-robin mode, all links
2641 		 * must tx arp to ensure all links rx an arp - otherwise
2642 		 * links may oscillate or not come up at all; if switch is
2643 		 * in something like xor mode, there is nothing we can
2644 		 * do - all replies will be rx'ed on same link causing slaves
2645 		 * to be unstable during low/no traffic periods
2646 		 */
2647 		if (IS_UP(slave->dev)) {
2648 			bond_arp_send_all(bond, slave);
2649 		}
2650 	}
2651 
2652 	if (do_failover) {
2653 		write_lock(&bond->curr_slave_lock);
2654 
2655 		bond_select_active_slave(bond);
2656 
2657 		write_unlock(&bond->curr_slave_lock);
2658 	}
2659 
2660 re_arm:
2661 	if (bond->params.arp_interval) {
2662 		mod_timer(&bond->arp_timer, jiffies + delta_in_ticks);
2663 	}
2664 out:
2665 	read_unlock(&bond->lock);
2666 }
2667 
2668 /*
2669  * When using arp monitoring in active-backup mode, this function is
2670  * called to determine if any backup slaves have went down or a new
2671  * current slave needs to be found.
2672  * The backup slaves never generate traffic, they are considered up by merely
2673  * receiving traffic. If the current slave goes down, each backup slave will
2674  * be given the opportunity to tx/rx an arp before being taken down - this
2675  * prevents all slaves from being taken down due to the current slave not
2676  * sending any traffic for the backups to receive. The arps are not necessarily
2677  * necessary, any tx and rx traffic will keep the current slave up. While any
2678  * rx traffic will keep the backup slaves up, the current slave is responsible
2679  * for generating traffic to keep them up regardless of any other traffic they
2680  * may have received.
2681  * see loadbalance_arp_monitor for arp monitoring in load balancing mode
2682  */
2683 void bond_activebackup_arp_mon(struct net_device *bond_dev)
2684 {
2685 	struct bonding *bond = bond_dev->priv;
2686 	struct slave *slave;
2687 	int delta_in_ticks;
2688 	int i;
2689 
2690 	read_lock(&bond->lock);
2691 
2692 	delta_in_ticks = (bond->params.arp_interval * HZ) / 1000;
2693 
2694 	if (bond->kill_timers) {
2695 		goto out;
2696 	}
2697 
2698 	if (bond->slave_cnt == 0) {
2699 		goto re_arm;
2700 	}
2701 
2702 	/* determine if any slave has come up or any backup slave has
2703 	 * gone down
2704 	 * TODO: what about up/down delay in arp mode? it wasn't here before
2705 	 *       so it can wait
2706 	 */
2707 	bond_for_each_slave(bond, slave, i) {
2708 		if (slave->link != BOND_LINK_UP) {
2709 			if ((jiffies - slave_last_rx(bond, slave)) <=
2710 			     delta_in_ticks) {
2711 
2712 				slave->link = BOND_LINK_UP;
2713 
2714 				write_lock(&bond->curr_slave_lock);
2715 
2716 				if ((!bond->curr_active_slave) &&
2717 				    ((jiffies - slave->dev->trans_start) <= delta_in_ticks)) {
2718 					bond_change_active_slave(bond, slave);
2719 					bond->current_arp_slave = NULL;
2720 				} else if (bond->curr_active_slave != slave) {
2721 					/* this slave has just come up but we
2722 					 * already have a current slave; this
2723 					 * can also happen if bond_enslave adds
2724 					 * a new slave that is up while we are
2725 					 * searching for a new slave
2726 					 */
2727 					bond_set_slave_inactive_flags(slave);
2728 					bond->current_arp_slave = NULL;
2729 				}
2730 
2731 				bond_set_carrier(bond);
2732 
2733 				if (slave == bond->curr_active_slave) {
2734 					printk(KERN_INFO DRV_NAME
2735 					       ": %s: %s is up and now the "
2736 					       "active interface\n",
2737 					       bond_dev->name,
2738 					       slave->dev->name);
2739 					netif_carrier_on(bond->dev);
2740 				} else {
2741 					printk(KERN_INFO DRV_NAME
2742 					       ": %s: backup interface %s is "
2743 					       "now up\n",
2744 					       bond_dev->name,
2745 					       slave->dev->name);
2746 				}
2747 
2748 				write_unlock(&bond->curr_slave_lock);
2749 			}
2750 		} else {
2751 			read_lock(&bond->curr_slave_lock);
2752 
2753 			if ((slave != bond->curr_active_slave) &&
2754 			    (!bond->current_arp_slave) &&
2755 			    (((jiffies - slave_last_rx(bond, slave)) >= 3*delta_in_ticks) &&
2756 			     bond_has_ip(bond))) {
2757 				/* a backup slave has gone down; three times
2758 				 * the delta allows the current slave to be
2759 				 * taken out before the backup slave.
2760 				 * note: a non-null current_arp_slave indicates
2761 				 * the curr_active_slave went down and we are
2762 				 * searching for a new one; under this
2763 				 * condition we only take the curr_active_slave
2764 				 * down - this gives each slave a chance to
2765 				 * tx/rx traffic before being taken out
2766 				 */
2767 
2768 				read_unlock(&bond->curr_slave_lock);
2769 
2770 				slave->link  = BOND_LINK_DOWN;
2771 
2772 				if (slave->link_failure_count < UINT_MAX) {
2773 					slave->link_failure_count++;
2774 				}
2775 
2776 				bond_set_slave_inactive_flags(slave);
2777 
2778 				printk(KERN_INFO DRV_NAME
2779 				       ": %s: backup interface %s is now down\n",
2780 				       bond_dev->name,
2781 				       slave->dev->name);
2782 			} else {
2783 				read_unlock(&bond->curr_slave_lock);
2784 			}
2785 		}
2786 	}
2787 
2788 	read_lock(&bond->curr_slave_lock);
2789 	slave = bond->curr_active_slave;
2790 	read_unlock(&bond->curr_slave_lock);
2791 
2792 	if (slave) {
2793 		/* if we have sent traffic in the past 2*arp_intervals but
2794 		 * haven't xmit and rx traffic in that time interval, select
2795 		 * a different slave. slave->jiffies is only updated when
2796 		 * a slave first becomes the curr_active_slave - not necessarily
2797 		 * after every arp; this ensures the slave has a full 2*delta
2798 		 * before being taken out. if a primary is being used, check
2799 		 * if it is up and needs to take over as the curr_active_slave
2800 		 */
2801 		if ((((jiffies - slave->dev->trans_start) >= (2*delta_in_ticks)) ||
2802 	    (((jiffies - slave_last_rx(bond, slave)) >= (2*delta_in_ticks)) &&
2803 	     bond_has_ip(bond))) &&
2804 		    ((jiffies - slave->jiffies) >= 2*delta_in_ticks)) {
2805 
2806 			slave->link  = BOND_LINK_DOWN;
2807 
2808 			if (slave->link_failure_count < UINT_MAX) {
2809 				slave->link_failure_count++;
2810 			}
2811 
2812 			printk(KERN_INFO DRV_NAME
2813 			       ": %s: link status down for active interface "
2814 			       "%s, disabling it\n",
2815 			       bond_dev->name,
2816 			       slave->dev->name);
2817 
2818 			write_lock(&bond->curr_slave_lock);
2819 
2820 			bond_select_active_slave(bond);
2821 			slave = bond->curr_active_slave;
2822 
2823 			write_unlock(&bond->curr_slave_lock);
2824 
2825 			bond->current_arp_slave = slave;
2826 
2827 			if (slave) {
2828 				slave->jiffies = jiffies;
2829 			}
2830 		} else if ((bond->primary_slave) &&
2831 			   (bond->primary_slave != slave) &&
2832 			   (bond->primary_slave->link == BOND_LINK_UP)) {
2833 			/* at this point, slave is the curr_active_slave */
2834 			printk(KERN_INFO DRV_NAME
2835 			       ": %s: changing from interface %s to primary "
2836 			       "interface %s\n",
2837 			       bond_dev->name,
2838 			       slave->dev->name,
2839 			       bond->primary_slave->dev->name);
2840 
2841 			/* primary is up so switch to it */
2842 			write_lock(&bond->curr_slave_lock);
2843 			bond_change_active_slave(bond, bond->primary_slave);
2844 			write_unlock(&bond->curr_slave_lock);
2845 
2846 			slave = bond->primary_slave;
2847 			slave->jiffies = jiffies;
2848 		} else {
2849 			bond->current_arp_slave = NULL;
2850 		}
2851 
2852 		/* the current slave must tx an arp to ensure backup slaves
2853 		 * rx traffic
2854 		 */
2855 		if (slave && bond_has_ip(bond)) {
2856 			bond_arp_send_all(bond, slave);
2857 		}
2858 	}
2859 
2860 	/* if we don't have a curr_active_slave, search for the next available
2861 	 * backup slave from the current_arp_slave and make it the candidate
2862 	 * for becoming the curr_active_slave
2863 	 */
2864 	if (!slave) {
2865 		if (!bond->current_arp_slave) {
2866 			bond->current_arp_slave = bond->first_slave;
2867 		}
2868 
2869 		if (bond->current_arp_slave) {
2870 			bond_set_slave_inactive_flags(bond->current_arp_slave);
2871 
2872 			/* search for next candidate */
2873 			bond_for_each_slave_from(bond, slave, i, bond->current_arp_slave->next) {
2874 				if (IS_UP(slave->dev)) {
2875 					slave->link = BOND_LINK_BACK;
2876 					bond_set_slave_active_flags(slave);
2877 					bond_arp_send_all(bond, slave);
2878 					slave->jiffies = jiffies;
2879 					bond->current_arp_slave = slave;
2880 					break;
2881 				}
2882 
2883 				/* if the link state is up at this point, we
2884 				 * mark it down - this can happen if we have
2885 				 * simultaneous link failures and
2886 				 * reselect_active_interface doesn't make this
2887 				 * one the current slave so it is still marked
2888 				 * up when it is actually down
2889 				 */
2890 				if (slave->link == BOND_LINK_UP) {
2891 					slave->link  = BOND_LINK_DOWN;
2892 					if (slave->link_failure_count < UINT_MAX) {
2893 						slave->link_failure_count++;
2894 					}
2895 
2896 					bond_set_slave_inactive_flags(slave);
2897 
2898 					printk(KERN_INFO DRV_NAME
2899 					       ": %s: backup interface %s is "
2900 					       "now down.\n",
2901 					       bond_dev->name,
2902 					       slave->dev->name);
2903 				}
2904 			}
2905 		}
2906 	}
2907 
2908 re_arm:
2909 	if (bond->params.arp_interval) {
2910 		mod_timer(&bond->arp_timer, jiffies + delta_in_ticks);
2911 	}
2912 out:
2913 	read_unlock(&bond->lock);
2914 }
2915 
2916 /*------------------------------ proc/seq_file-------------------------------*/
2917 
2918 #ifdef CONFIG_PROC_FS
2919 
2920 #define SEQ_START_TOKEN ((void *)1)
2921 
2922 static void *bond_info_seq_start(struct seq_file *seq, loff_t *pos)
2923 {
2924 	struct bonding *bond = seq->private;
2925 	loff_t off = 0;
2926 	struct slave *slave;
2927 	int i;
2928 
2929 	/* make sure the bond won't be taken away */
2930 	read_lock(&dev_base_lock);
2931 	read_lock_bh(&bond->lock);
2932 
2933 	if (*pos == 0) {
2934 		return SEQ_START_TOKEN;
2935 	}
2936 
2937 	bond_for_each_slave(bond, slave, i) {
2938 		if (++off == *pos) {
2939 			return slave;
2940 		}
2941 	}
2942 
2943 	return NULL;
2944 }
2945 
2946 static void *bond_info_seq_next(struct seq_file *seq, void *v, loff_t *pos)
2947 {
2948 	struct bonding *bond = seq->private;
2949 	struct slave *slave = v;
2950 
2951 	++*pos;
2952 	if (v == SEQ_START_TOKEN) {
2953 		return bond->first_slave;
2954 	}
2955 
2956 	slave = slave->next;
2957 
2958 	return (slave == bond->first_slave) ? NULL : slave;
2959 }
2960 
2961 static void bond_info_seq_stop(struct seq_file *seq, void *v)
2962 {
2963 	struct bonding *bond = seq->private;
2964 
2965 	read_unlock_bh(&bond->lock);
2966 	read_unlock(&dev_base_lock);
2967 }
2968 
2969 static void bond_info_show_master(struct seq_file *seq)
2970 {
2971 	struct bonding *bond = seq->private;
2972 	struct slave *curr;
2973 	int i;
2974 	u32 target;
2975 
2976 	read_lock(&bond->curr_slave_lock);
2977 	curr = bond->curr_active_slave;
2978 	read_unlock(&bond->curr_slave_lock);
2979 
2980 	seq_printf(seq, "Bonding Mode: %s\n",
2981 		   bond_mode_name(bond->params.mode));
2982 
2983 	if (bond->params.mode == BOND_MODE_XOR ||
2984 		bond->params.mode == BOND_MODE_8023AD) {
2985 		seq_printf(seq, "Transmit Hash Policy: %s (%d)\n",
2986 			xmit_hashtype_tbl[bond->params.xmit_policy].modename,
2987 			bond->params.xmit_policy);
2988 	}
2989 
2990 	if (USES_PRIMARY(bond->params.mode)) {
2991 		seq_printf(seq, "Primary Slave: %s\n",
2992 			   (bond->primary_slave) ?
2993 			   bond->primary_slave->dev->name : "None");
2994 
2995 		seq_printf(seq, "Currently Active Slave: %s\n",
2996 			   (curr) ? curr->dev->name : "None");
2997 	}
2998 
2999 	seq_printf(seq, "MII Status: %s\n", netif_carrier_ok(bond->dev) ?
3000 		   "up" : "down");
3001 	seq_printf(seq, "MII Polling Interval (ms): %d\n", bond->params.miimon);
3002 	seq_printf(seq, "Up Delay (ms): %d\n",
3003 		   bond->params.updelay * bond->params.miimon);
3004 	seq_printf(seq, "Down Delay (ms): %d\n",
3005 		   bond->params.downdelay * bond->params.miimon);
3006 
3007 
3008 	/* ARP information */
3009 	if(bond->params.arp_interval > 0) {
3010 		int printed=0;
3011 		seq_printf(seq, "ARP Polling Interval (ms): %d\n",
3012 				bond->params.arp_interval);
3013 
3014 		seq_printf(seq, "ARP IP target/s (n.n.n.n form):");
3015 
3016 		for(i = 0; (i < BOND_MAX_ARP_TARGETS) ;i++) {
3017 			if (!bond->params.arp_targets[i])
3018 				continue;
3019 			if (printed)
3020 				seq_printf(seq, ",");
3021 			target = ntohl(bond->params.arp_targets[i]);
3022 			seq_printf(seq, " %d.%d.%d.%d", HIPQUAD(target));
3023 			printed = 1;
3024 		}
3025 		seq_printf(seq, "\n");
3026 	}
3027 
3028 	if (bond->params.mode == BOND_MODE_8023AD) {
3029 		struct ad_info ad_info;
3030 
3031 		seq_puts(seq, "\n802.3ad info\n");
3032 		seq_printf(seq, "LACP rate: %s\n",
3033 			   (bond->params.lacp_fast) ? "fast" : "slow");
3034 
3035 		if (bond_3ad_get_active_agg_info(bond, &ad_info)) {
3036 			seq_printf(seq, "bond %s has no active aggregator\n",
3037 				   bond->dev->name);
3038 		} else {
3039 			seq_printf(seq, "Active Aggregator Info:\n");
3040 
3041 			seq_printf(seq, "\tAggregator ID: %d\n",
3042 				   ad_info.aggregator_id);
3043 			seq_printf(seq, "\tNumber of ports: %d\n",
3044 				   ad_info.ports);
3045 			seq_printf(seq, "\tActor Key: %d\n",
3046 				   ad_info.actor_key);
3047 			seq_printf(seq, "\tPartner Key: %d\n",
3048 				   ad_info.partner_key);
3049 			seq_printf(seq, "\tPartner Mac Address: %02x:%02x:%02x:%02x:%02x:%02x\n",
3050 				   ad_info.partner_system[0],
3051 				   ad_info.partner_system[1],
3052 				   ad_info.partner_system[2],
3053 				   ad_info.partner_system[3],
3054 				   ad_info.partner_system[4],
3055 				   ad_info.partner_system[5]);
3056 		}
3057 	}
3058 }
3059 
3060 static void bond_info_show_slave(struct seq_file *seq, const struct slave *slave)
3061 {
3062 	struct bonding *bond = seq->private;
3063 
3064 	seq_printf(seq, "\nSlave Interface: %s\n", slave->dev->name);
3065 	seq_printf(seq, "MII Status: %s\n",
3066 		   (slave->link == BOND_LINK_UP) ?  "up" : "down");
3067 	seq_printf(seq, "Link Failure Count: %u\n",
3068 		   slave->link_failure_count);
3069 
3070 	seq_printf(seq,
3071 		   "Permanent HW addr: %02x:%02x:%02x:%02x:%02x:%02x\n",
3072 		   slave->perm_hwaddr[0], slave->perm_hwaddr[1],
3073 		   slave->perm_hwaddr[2], slave->perm_hwaddr[3],
3074 		   slave->perm_hwaddr[4], slave->perm_hwaddr[5]);
3075 
3076 	if (bond->params.mode == BOND_MODE_8023AD) {
3077 		const struct aggregator *agg
3078 			= SLAVE_AD_INFO(slave).port.aggregator;
3079 
3080 		if (agg) {
3081 			seq_printf(seq, "Aggregator ID: %d\n",
3082 				   agg->aggregator_identifier);
3083 		} else {
3084 			seq_puts(seq, "Aggregator ID: N/A\n");
3085 		}
3086 	}
3087 }
3088 
3089 static int bond_info_seq_show(struct seq_file *seq, void *v)
3090 {
3091 	if (v == SEQ_START_TOKEN) {
3092 		seq_printf(seq, "%s\n", version);
3093 		bond_info_show_master(seq);
3094 	} else {
3095 		bond_info_show_slave(seq, v);
3096 	}
3097 
3098 	return 0;
3099 }
3100 
3101 static struct seq_operations bond_info_seq_ops = {
3102 	.start = bond_info_seq_start,
3103 	.next  = bond_info_seq_next,
3104 	.stop  = bond_info_seq_stop,
3105 	.show  = bond_info_seq_show,
3106 };
3107 
3108 static int bond_info_open(struct inode *inode, struct file *file)
3109 {
3110 	struct seq_file *seq;
3111 	struct proc_dir_entry *proc;
3112 	int res;
3113 
3114 	res = seq_open(file, &bond_info_seq_ops);
3115 	if (!res) {
3116 		/* recover the pointer buried in proc_dir_entry data */
3117 		seq = file->private_data;
3118 		proc = PDE(inode);
3119 		seq->private = proc->data;
3120 	}
3121 
3122 	return res;
3123 }
3124 
3125 static struct file_operations bond_info_fops = {
3126 	.owner   = THIS_MODULE,
3127 	.open    = bond_info_open,
3128 	.read    = seq_read,
3129 	.llseek  = seq_lseek,
3130 	.release = seq_release,
3131 };
3132 
3133 static int bond_create_proc_entry(struct bonding *bond)
3134 {
3135 	struct net_device *bond_dev = bond->dev;
3136 
3137 	if (bond_proc_dir) {
3138 		bond->proc_entry = create_proc_entry(bond_dev->name,
3139 						     S_IRUGO,
3140 						     bond_proc_dir);
3141 		if (bond->proc_entry == NULL) {
3142 			printk(KERN_WARNING DRV_NAME
3143 			       ": Warning: Cannot create /proc/net/%s/%s\n",
3144 			       DRV_NAME, bond_dev->name);
3145 		} else {
3146 			bond->proc_entry->data = bond;
3147 			bond->proc_entry->proc_fops = &bond_info_fops;
3148 			bond->proc_entry->owner = THIS_MODULE;
3149 			memcpy(bond->proc_file_name, bond_dev->name, IFNAMSIZ);
3150 		}
3151 	}
3152 
3153 	return 0;
3154 }
3155 
3156 static void bond_remove_proc_entry(struct bonding *bond)
3157 {
3158 	if (bond_proc_dir && bond->proc_entry) {
3159 		remove_proc_entry(bond->proc_file_name, bond_proc_dir);
3160 		memset(bond->proc_file_name, 0, IFNAMSIZ);
3161 		bond->proc_entry = NULL;
3162 	}
3163 }
3164 
3165 /* Create the bonding directory under /proc/net, if doesn't exist yet.
3166  * Caller must hold rtnl_lock.
3167  */
3168 static void bond_create_proc_dir(void)
3169 {
3170 	int len = strlen(DRV_NAME);
3171 
3172 	for (bond_proc_dir = proc_net->subdir; bond_proc_dir;
3173 	     bond_proc_dir = bond_proc_dir->next) {
3174 		if ((bond_proc_dir->namelen == len) &&
3175 		    !memcmp(bond_proc_dir->name, DRV_NAME, len)) {
3176 			break;
3177 		}
3178 	}
3179 
3180 	if (!bond_proc_dir) {
3181 		bond_proc_dir = proc_mkdir(DRV_NAME, proc_net);
3182 		if (bond_proc_dir) {
3183 			bond_proc_dir->owner = THIS_MODULE;
3184 		} else {
3185 			printk(KERN_WARNING DRV_NAME
3186 				": Warning: cannot create /proc/net/%s\n",
3187 				DRV_NAME);
3188 		}
3189 	}
3190 }
3191 
3192 /* Destroy the bonding directory under /proc/net, if empty.
3193  * Caller must hold rtnl_lock.
3194  */
3195 static void bond_destroy_proc_dir(void)
3196 {
3197 	struct proc_dir_entry *de;
3198 
3199 	if (!bond_proc_dir) {
3200 		return;
3201 	}
3202 
3203 	/* verify that the /proc dir is empty */
3204 	for (de = bond_proc_dir->subdir; de; de = de->next) {
3205 		/* ignore . and .. */
3206 		if (*(de->name) != '.') {
3207 			break;
3208 		}
3209 	}
3210 
3211 	if (de) {
3212 		if (bond_proc_dir->owner == THIS_MODULE) {
3213 			bond_proc_dir->owner = NULL;
3214 		}
3215 	} else {
3216 		remove_proc_entry(DRV_NAME, proc_net);
3217 		bond_proc_dir = NULL;
3218 	}
3219 }
3220 #endif /* CONFIG_PROC_FS */
3221 
3222 /*-------------------------- netdev event handling --------------------------*/
3223 
3224 /*
3225  * Change device name
3226  */
3227 static int bond_event_changename(struct bonding *bond)
3228 {
3229 #ifdef CONFIG_PROC_FS
3230 	bond_remove_proc_entry(bond);
3231 	bond_create_proc_entry(bond);
3232 #endif
3233 	down_write(&(bonding_rwsem));
3234         bond_destroy_sysfs_entry(bond);
3235         bond_create_sysfs_entry(bond);
3236 	up_write(&(bonding_rwsem));
3237 	return NOTIFY_DONE;
3238 }
3239 
3240 static int bond_master_netdev_event(unsigned long event, struct net_device *bond_dev)
3241 {
3242 	struct bonding *event_bond = bond_dev->priv;
3243 
3244 	switch (event) {
3245 	case NETDEV_CHANGENAME:
3246 		return bond_event_changename(event_bond);
3247 	case NETDEV_UNREGISTER:
3248 		/*
3249 		 * TODO: remove a bond from the list?
3250 		 */
3251 		break;
3252 	default:
3253 		break;
3254 	}
3255 
3256 	return NOTIFY_DONE;
3257 }
3258 
3259 static int bond_slave_netdev_event(unsigned long event, struct net_device *slave_dev)
3260 {
3261 	struct net_device *bond_dev = slave_dev->master;
3262 	struct bonding *bond = bond_dev->priv;
3263 
3264 	switch (event) {
3265 	case NETDEV_UNREGISTER:
3266 		if (bond_dev) {
3267 			bond_release(bond_dev, slave_dev);
3268 		}
3269 		break;
3270 	case NETDEV_CHANGE:
3271 		/*
3272 		 * TODO: is this what we get if somebody
3273 		 * sets up a hierarchical bond, then rmmod's
3274 		 * one of the slave bonding devices?
3275 		 */
3276 		break;
3277 	case NETDEV_DOWN:
3278 		/*
3279 		 * ... Or is it this?
3280 		 */
3281 		break;
3282 	case NETDEV_CHANGEMTU:
3283 		/*
3284 		 * TODO: Should slaves be allowed to
3285 		 * independently alter their MTU?  For
3286 		 * an active-backup bond, slaves need
3287 		 * not be the same type of device, so
3288 		 * MTUs may vary.  For other modes,
3289 		 * slaves arguably should have the
3290 		 * same MTUs. To do this, we'd need to
3291 		 * take over the slave's change_mtu
3292 		 * function for the duration of their
3293 		 * servitude.
3294 		 */
3295 		break;
3296 	case NETDEV_CHANGENAME:
3297 		/*
3298 		 * TODO: handle changing the primary's name
3299 		 */
3300 		break;
3301 	case NETDEV_FEAT_CHANGE:
3302 		bond_compute_features(bond);
3303 		break;
3304 	default:
3305 		break;
3306 	}
3307 
3308 	return NOTIFY_DONE;
3309 }
3310 
3311 /*
3312  * bond_netdev_event: handle netdev notifier chain events.
3313  *
3314  * This function receives events for the netdev chain.  The caller (an
3315  * ioctl handler calling blocking_notifier_call_chain) holds the necessary
3316  * locks for us to safely manipulate the slave devices (RTNL lock,
3317  * dev_probe_lock).
3318  */
3319 static int bond_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
3320 {
3321 	struct net_device *event_dev = (struct net_device *)ptr;
3322 
3323 	dprintk("event_dev: %s, event: %lx\n",
3324 		(event_dev ? event_dev->name : "None"),
3325 		event);
3326 
3327 	if (!(event_dev->priv_flags & IFF_BONDING))
3328 		return NOTIFY_DONE;
3329 
3330 	if (event_dev->flags & IFF_MASTER) {
3331 		dprintk("IFF_MASTER\n");
3332 		return bond_master_netdev_event(event, event_dev);
3333 	}
3334 
3335 	if (event_dev->flags & IFF_SLAVE) {
3336 		dprintk("IFF_SLAVE\n");
3337 		return bond_slave_netdev_event(event, event_dev);
3338 	}
3339 
3340 	return NOTIFY_DONE;
3341 }
3342 
3343 /*
3344  * bond_inetaddr_event: handle inetaddr notifier chain events.
3345  *
3346  * We keep track of device IPs primarily to use as source addresses in
3347  * ARP monitor probes (rather than spewing out broadcasts all the time).
3348  *
3349  * We track one IP for the main device (if it has one), plus one per VLAN.
3350  */
3351 static int bond_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
3352 {
3353 	struct in_ifaddr *ifa = ptr;
3354 	struct net_device *vlan_dev, *event_dev = ifa->ifa_dev->dev;
3355 	struct bonding *bond, *bond_next;
3356 	struct vlan_entry *vlan, *vlan_next;
3357 
3358 	list_for_each_entry_safe(bond, bond_next, &bond_dev_list, bond_list) {
3359 		if (bond->dev == event_dev) {
3360 			switch (event) {
3361 			case NETDEV_UP:
3362 				bond->master_ip = ifa->ifa_local;
3363 				return NOTIFY_OK;
3364 			case NETDEV_DOWN:
3365 				bond->master_ip = bond_glean_dev_ip(bond->dev);
3366 				return NOTIFY_OK;
3367 			default:
3368 				return NOTIFY_DONE;
3369 			}
3370 		}
3371 
3372 		if (list_empty(&bond->vlan_list))
3373 			continue;
3374 
3375 		list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
3376 					 vlan_list) {
3377 			vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
3378 			if (vlan_dev == event_dev) {
3379 				switch (event) {
3380 				case NETDEV_UP:
3381 					vlan->vlan_ip = ifa->ifa_local;
3382 					return NOTIFY_OK;
3383 				case NETDEV_DOWN:
3384 					vlan->vlan_ip =
3385 						bond_glean_dev_ip(vlan_dev);
3386 					return NOTIFY_OK;
3387 				default:
3388 					return NOTIFY_DONE;
3389 				}
3390 			}
3391 		}
3392 	}
3393 	return NOTIFY_DONE;
3394 }
3395 
3396 static struct notifier_block bond_netdev_notifier = {
3397 	.notifier_call = bond_netdev_event,
3398 };
3399 
3400 static struct notifier_block bond_inetaddr_notifier = {
3401 	.notifier_call = bond_inetaddr_event,
3402 };
3403 
3404 /*-------------------------- Packet type handling ---------------------------*/
3405 
3406 /* register to receive lacpdus on a bond */
3407 static void bond_register_lacpdu(struct bonding *bond)
3408 {
3409 	struct packet_type *pk_type = &(BOND_AD_INFO(bond).ad_pkt_type);
3410 
3411 	/* initialize packet type */
3412 	pk_type->type = PKT_TYPE_LACPDU;
3413 	pk_type->dev = bond->dev;
3414 	pk_type->func = bond_3ad_lacpdu_recv;
3415 
3416 	dev_add_pack(pk_type);
3417 }
3418 
3419 /* unregister to receive lacpdus on a bond */
3420 static void bond_unregister_lacpdu(struct bonding *bond)
3421 {
3422 	dev_remove_pack(&(BOND_AD_INFO(bond).ad_pkt_type));
3423 }
3424 
3425 void bond_register_arp(struct bonding *bond)
3426 {
3427 	struct packet_type *pt = &bond->arp_mon_pt;
3428 
3429 	pt->type = htons(ETH_P_ARP);
3430 	pt->dev = NULL; /*bond->dev;XXX*/
3431 	pt->func = bond_arp_rcv;
3432 	dev_add_pack(pt);
3433 }
3434 
3435 void bond_unregister_arp(struct bonding *bond)
3436 {
3437 	dev_remove_pack(&bond->arp_mon_pt);
3438 }
3439 
3440 /*---------------------------- Hashing Policies -----------------------------*/
3441 
3442 /*
3443  * Hash for the the output device based upon layer 3 and layer 4 data. If
3444  * the packet is a frag or not TCP or UDP, just use layer 3 data.  If it is
3445  * altogether not IP, mimic bond_xmit_hash_policy_l2()
3446  */
3447 static int bond_xmit_hash_policy_l34(struct sk_buff *skb,
3448 				    struct net_device *bond_dev, int count)
3449 {
3450 	struct ethhdr *data = (struct ethhdr *)skb->data;
3451 	struct iphdr *iph = skb->nh.iph;
3452 	u16 *layer4hdr = (u16 *)((u32 *)iph + iph->ihl);
3453 	int layer4_xor = 0;
3454 
3455 	if (skb->protocol == __constant_htons(ETH_P_IP)) {
3456 		if (!(iph->frag_off & __constant_htons(IP_MF|IP_OFFSET)) &&
3457 		    (iph->protocol == IPPROTO_TCP ||
3458 		     iph->protocol == IPPROTO_UDP)) {
3459 			layer4_xor = htons((*layer4hdr ^ *(layer4hdr + 1)));
3460 		}
3461 		return (layer4_xor ^
3462 			((ntohl(iph->saddr ^ iph->daddr)) & 0xffff)) % count;
3463 
3464 	}
3465 
3466 	return (data->h_dest[5] ^ bond_dev->dev_addr[5]) % count;
3467 }
3468 
3469 /*
3470  * Hash for the output device based upon layer 2 data
3471  */
3472 static int bond_xmit_hash_policy_l2(struct sk_buff *skb,
3473 				   struct net_device *bond_dev, int count)
3474 {
3475 	struct ethhdr *data = (struct ethhdr *)skb->data;
3476 
3477 	return (data->h_dest[5] ^ bond_dev->dev_addr[5]) % count;
3478 }
3479 
3480 /*-------------------------- Device entry points ----------------------------*/
3481 
3482 static int bond_open(struct net_device *bond_dev)
3483 {
3484 	struct bonding *bond = bond_dev->priv;
3485 	struct timer_list *mii_timer = &bond->mii_timer;
3486 	struct timer_list *arp_timer = &bond->arp_timer;
3487 
3488 	bond->kill_timers = 0;
3489 
3490 	if ((bond->params.mode == BOND_MODE_TLB) ||
3491 	    (bond->params.mode == BOND_MODE_ALB)) {
3492 		struct timer_list *alb_timer = &(BOND_ALB_INFO(bond).alb_timer);
3493 
3494 		/* bond_alb_initialize must be called before the timer
3495 		 * is started.
3496 		 */
3497 		if (bond_alb_initialize(bond, (bond->params.mode == BOND_MODE_ALB))) {
3498 			/* something went wrong - fail the open operation */
3499 			return -1;
3500 		}
3501 
3502 		init_timer(alb_timer);
3503 		alb_timer->expires  = jiffies + 1;
3504 		alb_timer->data     = (unsigned long)bond;
3505 		alb_timer->function = (void *)&bond_alb_monitor;
3506 		add_timer(alb_timer);
3507 	}
3508 
3509 	if (bond->params.miimon) {  /* link check interval, in milliseconds. */
3510 		init_timer(mii_timer);
3511 		mii_timer->expires  = jiffies + 1;
3512 		mii_timer->data     = (unsigned long)bond_dev;
3513 		mii_timer->function = (void *)&bond_mii_monitor;
3514 		add_timer(mii_timer);
3515 	}
3516 
3517 	if (bond->params.arp_interval) {  /* arp interval, in milliseconds. */
3518 		init_timer(arp_timer);
3519 		arp_timer->expires  = jiffies + 1;
3520 		arp_timer->data     = (unsigned long)bond_dev;
3521 		if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
3522 			arp_timer->function = (void *)&bond_activebackup_arp_mon;
3523 		} else {
3524 			arp_timer->function = (void *)&bond_loadbalance_arp_mon;
3525 		}
3526 		if (bond->params.arp_validate)
3527 			bond_register_arp(bond);
3528 
3529 		add_timer(arp_timer);
3530 	}
3531 
3532 	if (bond->params.mode == BOND_MODE_8023AD) {
3533 		struct timer_list *ad_timer = &(BOND_AD_INFO(bond).ad_timer);
3534 		init_timer(ad_timer);
3535 		ad_timer->expires  = jiffies + 1;
3536 		ad_timer->data     = (unsigned long)bond;
3537 		ad_timer->function = (void *)&bond_3ad_state_machine_handler;
3538 		add_timer(ad_timer);
3539 
3540 		/* register to receive LACPDUs */
3541 		bond_register_lacpdu(bond);
3542 	}
3543 
3544 	return 0;
3545 }
3546 
3547 static int bond_close(struct net_device *bond_dev)
3548 {
3549 	struct bonding *bond = bond_dev->priv;
3550 
3551 	if (bond->params.mode == BOND_MODE_8023AD) {
3552 		/* Unregister the receive of LACPDUs */
3553 		bond_unregister_lacpdu(bond);
3554 	}
3555 
3556 	if (bond->params.arp_validate)
3557 		bond_unregister_arp(bond);
3558 
3559 	write_lock_bh(&bond->lock);
3560 
3561 
3562 	/* signal timers not to re-arm */
3563 	bond->kill_timers = 1;
3564 
3565 	write_unlock_bh(&bond->lock);
3566 
3567 	/* del_timer_sync must run without holding the bond->lock
3568 	 * because a running timer might be trying to hold it too
3569 	 */
3570 
3571 	if (bond->params.miimon) {  /* link check interval, in milliseconds. */
3572 		del_timer_sync(&bond->mii_timer);
3573 	}
3574 
3575 	if (bond->params.arp_interval) {  /* arp interval, in milliseconds. */
3576 		del_timer_sync(&bond->arp_timer);
3577 	}
3578 
3579 	switch (bond->params.mode) {
3580 	case BOND_MODE_8023AD:
3581 		del_timer_sync(&(BOND_AD_INFO(bond).ad_timer));
3582 		break;
3583 	case BOND_MODE_TLB:
3584 	case BOND_MODE_ALB:
3585 		del_timer_sync(&(BOND_ALB_INFO(bond).alb_timer));
3586 		break;
3587 	default:
3588 		break;
3589 	}
3590 
3591 
3592 	if ((bond->params.mode == BOND_MODE_TLB) ||
3593 	    (bond->params.mode == BOND_MODE_ALB)) {
3594 		/* Must be called only after all
3595 		 * slaves have been released
3596 		 */
3597 		bond_alb_deinitialize(bond);
3598 	}
3599 
3600 	return 0;
3601 }
3602 
3603 static struct net_device_stats *bond_get_stats(struct net_device *bond_dev)
3604 {
3605 	struct bonding *bond = bond_dev->priv;
3606 	struct net_device_stats *stats = &(bond->stats), *sstats;
3607 	struct slave *slave;
3608 	int i;
3609 
3610 	memset(stats, 0, sizeof(struct net_device_stats));
3611 
3612 	read_lock_bh(&bond->lock);
3613 
3614 	bond_for_each_slave(bond, slave, i) {
3615 		if (slave->dev->get_stats) {
3616 			sstats = slave->dev->get_stats(slave->dev);
3617 
3618 			stats->rx_packets += sstats->rx_packets;
3619 			stats->rx_bytes += sstats->rx_bytes;
3620 			stats->rx_errors += sstats->rx_errors;
3621 			stats->rx_dropped += sstats->rx_dropped;
3622 
3623 			stats->tx_packets += sstats->tx_packets;
3624 			stats->tx_bytes += sstats->tx_bytes;
3625 			stats->tx_errors += sstats->tx_errors;
3626 			stats->tx_dropped += sstats->tx_dropped;
3627 
3628 			stats->multicast += sstats->multicast;
3629 			stats->collisions += sstats->collisions;
3630 
3631 			stats->rx_length_errors += sstats->rx_length_errors;
3632 			stats->rx_over_errors += sstats->rx_over_errors;
3633 			stats->rx_crc_errors += sstats->rx_crc_errors;
3634 			stats->rx_frame_errors += sstats->rx_frame_errors;
3635 			stats->rx_fifo_errors += sstats->rx_fifo_errors;
3636 			stats->rx_missed_errors += sstats->rx_missed_errors;
3637 
3638 			stats->tx_aborted_errors += sstats->tx_aborted_errors;
3639 			stats->tx_carrier_errors += sstats->tx_carrier_errors;
3640 			stats->tx_fifo_errors += sstats->tx_fifo_errors;
3641 			stats->tx_heartbeat_errors += sstats->tx_heartbeat_errors;
3642 			stats->tx_window_errors += sstats->tx_window_errors;
3643 		}
3644 	}
3645 
3646 	read_unlock_bh(&bond->lock);
3647 
3648 	return stats;
3649 }
3650 
3651 static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd)
3652 {
3653 	struct net_device *slave_dev = NULL;
3654 	struct ifbond k_binfo;
3655 	struct ifbond __user *u_binfo = NULL;
3656 	struct ifslave k_sinfo;
3657 	struct ifslave __user *u_sinfo = NULL;
3658 	struct mii_ioctl_data *mii = NULL;
3659 	int res = 0;
3660 
3661 	dprintk("bond_ioctl: master=%s, cmd=%d\n",
3662 		bond_dev->name, cmd);
3663 
3664 	switch (cmd) {
3665 	case SIOCGMIIPHY:
3666 		mii = if_mii(ifr);
3667 		if (!mii) {
3668 			return -EINVAL;
3669 		}
3670 		mii->phy_id = 0;
3671 		/* Fall Through */
3672 	case SIOCGMIIREG:
3673 		/*
3674 		 * We do this again just in case we were called by SIOCGMIIREG
3675 		 * instead of SIOCGMIIPHY.
3676 		 */
3677 		mii = if_mii(ifr);
3678 		if (!mii) {
3679 			return -EINVAL;
3680 		}
3681 
3682 		if (mii->reg_num == 1) {
3683 			struct bonding *bond = bond_dev->priv;
3684 			mii->val_out = 0;
3685 			read_lock_bh(&bond->lock);
3686 			read_lock(&bond->curr_slave_lock);
3687 			if (netif_carrier_ok(bond->dev)) {
3688 				mii->val_out = BMSR_LSTATUS;
3689 			}
3690 			read_unlock(&bond->curr_slave_lock);
3691 			read_unlock_bh(&bond->lock);
3692 		}
3693 
3694 		return 0;
3695 	case BOND_INFO_QUERY_OLD:
3696 	case SIOCBONDINFOQUERY:
3697 		u_binfo = (struct ifbond __user *)ifr->ifr_data;
3698 
3699 		if (copy_from_user(&k_binfo, u_binfo, sizeof(ifbond))) {
3700 			return -EFAULT;
3701 		}
3702 
3703 		res = bond_info_query(bond_dev, &k_binfo);
3704 		if (res == 0) {
3705 			if (copy_to_user(u_binfo, &k_binfo, sizeof(ifbond))) {
3706 				return -EFAULT;
3707 			}
3708 		}
3709 
3710 		return res;
3711 	case BOND_SLAVE_INFO_QUERY_OLD:
3712 	case SIOCBONDSLAVEINFOQUERY:
3713 		u_sinfo = (struct ifslave __user *)ifr->ifr_data;
3714 
3715 		if (copy_from_user(&k_sinfo, u_sinfo, sizeof(ifslave))) {
3716 			return -EFAULT;
3717 		}
3718 
3719 		res = bond_slave_info_query(bond_dev, &k_sinfo);
3720 		if (res == 0) {
3721 			if (copy_to_user(u_sinfo, &k_sinfo, sizeof(ifslave))) {
3722 				return -EFAULT;
3723 			}
3724 		}
3725 
3726 		return res;
3727 	default:
3728 		/* Go on */
3729 		break;
3730 	}
3731 
3732 	if (!capable(CAP_NET_ADMIN)) {
3733 		return -EPERM;
3734 	}
3735 
3736 	down_write(&(bonding_rwsem));
3737 	slave_dev = dev_get_by_name(ifr->ifr_slave);
3738 
3739 	dprintk("slave_dev=%p: \n", slave_dev);
3740 
3741 	if (!slave_dev) {
3742 		res = -ENODEV;
3743 	} else {
3744 		dprintk("slave_dev->name=%s: \n", slave_dev->name);
3745 		switch (cmd) {
3746 		case BOND_ENSLAVE_OLD:
3747 		case SIOCBONDENSLAVE:
3748 			res = bond_enslave(bond_dev, slave_dev);
3749 			break;
3750 		case BOND_RELEASE_OLD:
3751 		case SIOCBONDRELEASE:
3752 			res = bond_release(bond_dev, slave_dev);
3753 			break;
3754 		case BOND_SETHWADDR_OLD:
3755 		case SIOCBONDSETHWADDR:
3756 			res = bond_sethwaddr(bond_dev, slave_dev);
3757 			break;
3758 		case BOND_CHANGE_ACTIVE_OLD:
3759 		case SIOCBONDCHANGEACTIVE:
3760 			res = bond_ioctl_change_active(bond_dev, slave_dev);
3761 			break;
3762 		default:
3763 			res = -EOPNOTSUPP;
3764 		}
3765 
3766 		dev_put(slave_dev);
3767 	}
3768 
3769 	up_write(&(bonding_rwsem));
3770 	return res;
3771 }
3772 
3773 static void bond_set_multicast_list(struct net_device *bond_dev)
3774 {
3775 	struct bonding *bond = bond_dev->priv;
3776 	struct dev_mc_list *dmi;
3777 
3778 	write_lock_bh(&bond->lock);
3779 
3780 	/*
3781 	 * Do promisc before checking multicast_mode
3782 	 */
3783 	if ((bond_dev->flags & IFF_PROMISC) && !(bond->flags & IFF_PROMISC)) {
3784 		bond_set_promiscuity(bond, 1);
3785 	}
3786 
3787 	if (!(bond_dev->flags & IFF_PROMISC) && (bond->flags & IFF_PROMISC)) {
3788 		bond_set_promiscuity(bond, -1);
3789 	}
3790 
3791 	/* set allmulti flag to slaves */
3792 	if ((bond_dev->flags & IFF_ALLMULTI) && !(bond->flags & IFF_ALLMULTI)) {
3793 		bond_set_allmulti(bond, 1);
3794 	}
3795 
3796 	if (!(bond_dev->flags & IFF_ALLMULTI) && (bond->flags & IFF_ALLMULTI)) {
3797 		bond_set_allmulti(bond, -1);
3798 	}
3799 
3800 	bond->flags = bond_dev->flags;
3801 
3802 	/* looking for addresses to add to slaves' mc list */
3803 	for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
3804 		if (!bond_mc_list_find_dmi(dmi, bond->mc_list)) {
3805 			bond_mc_add(bond, dmi->dmi_addr, dmi->dmi_addrlen);
3806 		}
3807 	}
3808 
3809 	/* looking for addresses to delete from slaves' list */
3810 	for (dmi = bond->mc_list; dmi; dmi = dmi->next) {
3811 		if (!bond_mc_list_find_dmi(dmi, bond_dev->mc_list)) {
3812 			bond_mc_delete(bond, dmi->dmi_addr, dmi->dmi_addrlen);
3813 		}
3814 	}
3815 
3816 	/* save master's multicast list */
3817 	bond_mc_list_destroy(bond);
3818 	bond_mc_list_copy(bond_dev->mc_list, bond, GFP_ATOMIC);
3819 
3820 	write_unlock_bh(&bond->lock);
3821 }
3822 
3823 /*
3824  * Change the MTU of all of a master's slaves to match the master
3825  */
3826 static int bond_change_mtu(struct net_device *bond_dev, int new_mtu)
3827 {
3828 	struct bonding *bond = bond_dev->priv;
3829 	struct slave *slave, *stop_at;
3830 	int res = 0;
3831 	int i;
3832 
3833 	dprintk("bond=%p, name=%s, new_mtu=%d\n", bond,
3834 		(bond_dev ? bond_dev->name : "None"), new_mtu);
3835 
3836 	/* Can't hold bond->lock with bh disabled here since
3837 	 * some base drivers panic. On the other hand we can't
3838 	 * hold bond->lock without bh disabled because we'll
3839 	 * deadlock. The only solution is to rely on the fact
3840 	 * that we're under rtnl_lock here, and the slaves
3841 	 * list won't change. This doesn't solve the problem
3842 	 * of setting the slave's MTU while it is
3843 	 * transmitting, but the assumption is that the base
3844 	 * driver can handle that.
3845 	 *
3846 	 * TODO: figure out a way to safely iterate the slaves
3847 	 * list, but without holding a lock around the actual
3848 	 * call to the base driver.
3849 	 */
3850 
3851 	bond_for_each_slave(bond, slave, i) {
3852 		dprintk("s %p s->p %p c_m %p\n", slave,
3853 			slave->prev, slave->dev->change_mtu);
3854 
3855 		res = dev_set_mtu(slave->dev, new_mtu);
3856 
3857 		if (res) {
3858 			/* If we failed to set the slave's mtu to the new value
3859 			 * we must abort the operation even in ACTIVE_BACKUP
3860 			 * mode, because if we allow the backup slaves to have
3861 			 * different mtu values than the active slave we'll
3862 			 * need to change their mtu when doing a failover. That
3863 			 * means changing their mtu from timer context, which
3864 			 * is probably not a good idea.
3865 			 */
3866 			dprintk("err %d %s\n", res, slave->dev->name);
3867 			goto unwind;
3868 		}
3869 	}
3870 
3871 	bond_dev->mtu = new_mtu;
3872 
3873 	return 0;
3874 
3875 unwind:
3876 	/* unwind from head to the slave that failed */
3877 	stop_at = slave;
3878 	bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
3879 		int tmp_res;
3880 
3881 		tmp_res = dev_set_mtu(slave->dev, bond_dev->mtu);
3882 		if (tmp_res) {
3883 			dprintk("unwind err %d dev %s\n", tmp_res,
3884 				slave->dev->name);
3885 		}
3886 	}
3887 
3888 	return res;
3889 }
3890 
3891 /*
3892  * Change HW address
3893  *
3894  * Note that many devices must be down to change the HW address, and
3895  * downing the master releases all slaves.  We can make bonds full of
3896  * bonding devices to test this, however.
3897  */
3898 static int bond_set_mac_address(struct net_device *bond_dev, void *addr)
3899 {
3900 	struct bonding *bond = bond_dev->priv;
3901 	struct sockaddr *sa = addr, tmp_sa;
3902 	struct slave *slave, *stop_at;
3903 	int res = 0;
3904 	int i;
3905 
3906 	dprintk("bond=%p, name=%s\n", bond, (bond_dev ? bond_dev->name : "None"));
3907 
3908 	if (!is_valid_ether_addr(sa->sa_data)) {
3909 		return -EADDRNOTAVAIL;
3910 	}
3911 
3912 	/* Can't hold bond->lock with bh disabled here since
3913 	 * some base drivers panic. On the other hand we can't
3914 	 * hold bond->lock without bh disabled because we'll
3915 	 * deadlock. The only solution is to rely on the fact
3916 	 * that we're under rtnl_lock here, and the slaves
3917 	 * list won't change. This doesn't solve the problem
3918 	 * of setting the slave's hw address while it is
3919 	 * transmitting, but the assumption is that the base
3920 	 * driver can handle that.
3921 	 *
3922 	 * TODO: figure out a way to safely iterate the slaves
3923 	 * list, but without holding a lock around the actual
3924 	 * call to the base driver.
3925 	 */
3926 
3927 	bond_for_each_slave(bond, slave, i) {
3928 		dprintk("slave %p %s\n", slave, slave->dev->name);
3929 
3930 		if (slave->dev->set_mac_address == NULL) {
3931 			res = -EOPNOTSUPP;
3932 			dprintk("EOPNOTSUPP %s\n", slave->dev->name);
3933 			goto unwind;
3934 		}
3935 
3936 		res = dev_set_mac_address(slave->dev, addr);
3937 		if (res) {
3938 			/* TODO: consider downing the slave
3939 			 * and retry ?
3940 			 * User should expect communications
3941 			 * breakage anyway until ARP finish
3942 			 * updating, so...
3943 			 */
3944 			dprintk("err %d %s\n", res, slave->dev->name);
3945 			goto unwind;
3946 		}
3947 	}
3948 
3949 	/* success */
3950 	memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
3951 	return 0;
3952 
3953 unwind:
3954 	memcpy(tmp_sa.sa_data, bond_dev->dev_addr, bond_dev->addr_len);
3955 	tmp_sa.sa_family = bond_dev->type;
3956 
3957 	/* unwind from head to the slave that failed */
3958 	stop_at = slave;
3959 	bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
3960 		int tmp_res;
3961 
3962 		tmp_res = dev_set_mac_address(slave->dev, &tmp_sa);
3963 		if (tmp_res) {
3964 			dprintk("unwind err %d dev %s\n", tmp_res,
3965 				slave->dev->name);
3966 		}
3967 	}
3968 
3969 	return res;
3970 }
3971 
3972 static int bond_xmit_roundrobin(struct sk_buff *skb, struct net_device *bond_dev)
3973 {
3974 	struct bonding *bond = bond_dev->priv;
3975 	struct slave *slave, *start_at;
3976 	int i;
3977 	int res = 1;
3978 
3979 	read_lock(&bond->lock);
3980 
3981 	if (!BOND_IS_OK(bond)) {
3982 		goto out;
3983 	}
3984 
3985 	read_lock(&bond->curr_slave_lock);
3986 	slave = start_at = bond->curr_active_slave;
3987 	read_unlock(&bond->curr_slave_lock);
3988 
3989 	if (!slave) {
3990 		goto out;
3991 	}
3992 
3993 	bond_for_each_slave_from(bond, slave, i, start_at) {
3994 		if (IS_UP(slave->dev) &&
3995 		    (slave->link == BOND_LINK_UP) &&
3996 		    (slave->state == BOND_STATE_ACTIVE)) {
3997 			res = bond_dev_queue_xmit(bond, skb, slave->dev);
3998 
3999 			write_lock(&bond->curr_slave_lock);
4000 			bond->curr_active_slave = slave->next;
4001 			write_unlock(&bond->curr_slave_lock);
4002 
4003 			break;
4004 		}
4005 	}
4006 
4007 
4008 out:
4009 	if (res) {
4010 		/* no suitable interface, frame not sent */
4011 		dev_kfree_skb(skb);
4012 	}
4013 	read_unlock(&bond->lock);
4014 	return 0;
4015 }
4016 
4017 static void bond_activebackup_xmit_copy(struct sk_buff *skb,
4018                                         struct bonding *bond,
4019                                         struct slave *slave)
4020 {
4021 	struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC);
4022 	struct ethhdr *eth_data;
4023 	u8 *hwaddr;
4024 	int res;
4025 
4026 	if (!skb2) {
4027 		printk(KERN_ERR DRV_NAME ": Error: "
4028 		       "bond_activebackup_xmit_copy(): skb_copy() failed\n");
4029 		return;
4030 	}
4031 
4032 	skb2->mac.raw = (unsigned char *)skb2->data;
4033 	eth_data = eth_hdr(skb2);
4034 
4035 	/* Pick an appropriate source MAC address
4036 	 *	-- use slave's perm MAC addr, unless used by bond
4037 	 *	-- otherwise, borrow active slave's perm MAC addr
4038 	 *	   since that will not be used
4039 	 */
4040 	hwaddr = slave->perm_hwaddr;
4041 	if (!memcmp(eth_data->h_source, hwaddr, ETH_ALEN))
4042 		hwaddr = bond->curr_active_slave->perm_hwaddr;
4043 
4044 	/* Set source MAC address appropriately */
4045 	memcpy(eth_data->h_source, hwaddr, ETH_ALEN);
4046 
4047 	res = bond_dev_queue_xmit(bond, skb2, slave->dev);
4048 	if (res)
4049 		dev_kfree_skb(skb2);
4050 
4051 	return;
4052 }
4053 
4054 /*
4055  * in active-backup mode, we know that bond->curr_active_slave is always valid if
4056  * the bond has a usable interface.
4057  */
4058 static int bond_xmit_activebackup(struct sk_buff *skb, struct net_device *bond_dev)
4059 {
4060 	struct bonding *bond = bond_dev->priv;
4061 	int res = 1;
4062 
4063 	read_lock(&bond->lock);
4064 	read_lock(&bond->curr_slave_lock);
4065 
4066 	if (!BOND_IS_OK(bond)) {
4067 		goto out;
4068 	}
4069 
4070 	if (!bond->curr_active_slave)
4071 		goto out;
4072 
4073 	/* Xmit IGMP frames on all slaves to ensure rapid fail-over
4074 	   for multicast traffic on snooping switches */
4075 	if (skb->protocol == __constant_htons(ETH_P_IP) &&
4076 	    skb->nh.iph->protocol == IPPROTO_IGMP) {
4077 		struct slave *slave, *active_slave;
4078 		int i;
4079 
4080 		active_slave = bond->curr_active_slave;
4081 		bond_for_each_slave_from_to(bond, slave, i, active_slave->next,
4082 		                            active_slave->prev)
4083 			if (IS_UP(slave->dev) &&
4084 			    (slave->link == BOND_LINK_UP))
4085 				bond_activebackup_xmit_copy(skb, bond, slave);
4086 	}
4087 
4088 	res = bond_dev_queue_xmit(bond, skb, bond->curr_active_slave->dev);
4089 
4090 out:
4091 	if (res) {
4092 		/* no suitable interface, frame not sent */
4093 		dev_kfree_skb(skb);
4094 	}
4095 	read_unlock(&bond->curr_slave_lock);
4096 	read_unlock(&bond->lock);
4097 	return 0;
4098 }
4099 
4100 /*
4101  * In bond_xmit_xor() , we determine the output device by using a pre-
4102  * determined xmit_hash_policy(), If the selected device is not enabled,
4103  * find the next active slave.
4104  */
4105 static int bond_xmit_xor(struct sk_buff *skb, struct net_device *bond_dev)
4106 {
4107 	struct bonding *bond = bond_dev->priv;
4108 	struct slave *slave, *start_at;
4109 	int slave_no;
4110 	int i;
4111 	int res = 1;
4112 
4113 	read_lock(&bond->lock);
4114 
4115 	if (!BOND_IS_OK(bond)) {
4116 		goto out;
4117 	}
4118 
4119 	slave_no = bond->xmit_hash_policy(skb, bond_dev, bond->slave_cnt);
4120 
4121 	bond_for_each_slave(bond, slave, i) {
4122 		slave_no--;
4123 		if (slave_no < 0) {
4124 			break;
4125 		}
4126 	}
4127 
4128 	start_at = slave;
4129 
4130 	bond_for_each_slave_from(bond, slave, i, start_at) {
4131 		if (IS_UP(slave->dev) &&
4132 		    (slave->link == BOND_LINK_UP) &&
4133 		    (slave->state == BOND_STATE_ACTIVE)) {
4134 			res = bond_dev_queue_xmit(bond, skb, slave->dev);
4135 			break;
4136 		}
4137 	}
4138 
4139 out:
4140 	if (res) {
4141 		/* no suitable interface, frame not sent */
4142 		dev_kfree_skb(skb);
4143 	}
4144 	read_unlock(&bond->lock);
4145 	return 0;
4146 }
4147 
4148 /*
4149  * in broadcast mode, we send everything to all usable interfaces.
4150  */
4151 static int bond_xmit_broadcast(struct sk_buff *skb, struct net_device *bond_dev)
4152 {
4153 	struct bonding *bond = bond_dev->priv;
4154 	struct slave *slave, *start_at;
4155 	struct net_device *tx_dev = NULL;
4156 	int i;
4157 	int res = 1;
4158 
4159 	read_lock(&bond->lock);
4160 
4161 	if (!BOND_IS_OK(bond)) {
4162 		goto out;
4163 	}
4164 
4165 	read_lock(&bond->curr_slave_lock);
4166 	start_at = bond->curr_active_slave;
4167 	read_unlock(&bond->curr_slave_lock);
4168 
4169 	if (!start_at) {
4170 		goto out;
4171 	}
4172 
4173 	bond_for_each_slave_from(bond, slave, i, start_at) {
4174 		if (IS_UP(slave->dev) &&
4175 		    (slave->link == BOND_LINK_UP) &&
4176 		    (slave->state == BOND_STATE_ACTIVE)) {
4177 			if (tx_dev) {
4178 				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
4179 				if (!skb2) {
4180 					printk(KERN_ERR DRV_NAME
4181 					       ": %s: Error: bond_xmit_broadcast(): "
4182 					       "skb_clone() failed\n",
4183 					       bond_dev->name);
4184 					continue;
4185 				}
4186 
4187 				res = bond_dev_queue_xmit(bond, skb2, tx_dev);
4188 				if (res) {
4189 					dev_kfree_skb(skb2);
4190 					continue;
4191 				}
4192 			}
4193 			tx_dev = slave->dev;
4194 		}
4195 	}
4196 
4197 	if (tx_dev) {
4198 		res = bond_dev_queue_xmit(bond, skb, tx_dev);
4199 	}
4200 
4201 out:
4202 	if (res) {
4203 		/* no suitable interface, frame not sent */
4204 		dev_kfree_skb(skb);
4205 	}
4206 	/* frame sent to all suitable interfaces */
4207 	read_unlock(&bond->lock);
4208 	return 0;
4209 }
4210 
4211 /*------------------------- Device initialization ---------------------------*/
4212 
4213 /*
4214  * set bond mode specific net device operations
4215  */
4216 void bond_set_mode_ops(struct bonding *bond, int mode)
4217 {
4218 	struct net_device *bond_dev = bond->dev;
4219 
4220 	switch (mode) {
4221 	case BOND_MODE_ROUNDROBIN:
4222 		bond_dev->hard_start_xmit = bond_xmit_roundrobin;
4223 		break;
4224 	case BOND_MODE_ACTIVEBACKUP:
4225 		bond_dev->hard_start_xmit = bond_xmit_activebackup;
4226 		break;
4227 	case BOND_MODE_XOR:
4228 		bond_dev->hard_start_xmit = bond_xmit_xor;
4229 		if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER34)
4230 			bond->xmit_hash_policy = bond_xmit_hash_policy_l34;
4231 		else
4232 			bond->xmit_hash_policy = bond_xmit_hash_policy_l2;
4233 		break;
4234 	case BOND_MODE_BROADCAST:
4235 		bond_dev->hard_start_xmit = bond_xmit_broadcast;
4236 		break;
4237 	case BOND_MODE_8023AD:
4238 		bond_set_master_3ad_flags(bond);
4239 		bond_dev->hard_start_xmit = bond_3ad_xmit_xor;
4240 		if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER34)
4241 			bond->xmit_hash_policy = bond_xmit_hash_policy_l34;
4242 		else
4243 			bond->xmit_hash_policy = bond_xmit_hash_policy_l2;
4244 		break;
4245 	case BOND_MODE_ALB:
4246 		bond_set_master_alb_flags(bond);
4247 		/* FALLTHRU */
4248 	case BOND_MODE_TLB:
4249 		bond_dev->hard_start_xmit = bond_alb_xmit;
4250 		bond_dev->set_mac_address = bond_alb_set_mac_address;
4251 		break;
4252 	default:
4253 		/* Should never happen, mode already checked */
4254 		printk(KERN_ERR DRV_NAME
4255 		       ": %s: Error: Unknown bonding mode %d\n",
4256 		       bond_dev->name,
4257 		       mode);
4258 		break;
4259 	}
4260 }
4261 
4262 static void bond_ethtool_get_drvinfo(struct net_device *bond_dev,
4263 				    struct ethtool_drvinfo *drvinfo)
4264 {
4265 	strncpy(drvinfo->driver, DRV_NAME, 32);
4266 	strncpy(drvinfo->version, DRV_VERSION, 32);
4267 	snprintf(drvinfo->fw_version, 32, "%d", BOND_ABI_VERSION);
4268 }
4269 
4270 static const struct ethtool_ops bond_ethtool_ops = {
4271 	.get_tx_csum		= ethtool_op_get_tx_csum,
4272 	.get_tso		= ethtool_op_get_tso,
4273 	.get_ufo		= ethtool_op_get_ufo,
4274 	.get_sg			= ethtool_op_get_sg,
4275 	.get_drvinfo		= bond_ethtool_get_drvinfo,
4276 };
4277 
4278 /*
4279  * Does not allocate but creates a /proc entry.
4280  * Allowed to fail.
4281  */
4282 static int bond_init(struct net_device *bond_dev, struct bond_params *params)
4283 {
4284 	struct bonding *bond = bond_dev->priv;
4285 
4286 	dprintk("Begin bond_init for %s\n", bond_dev->name);
4287 
4288 	/* initialize rwlocks */
4289 	rwlock_init(&bond->lock);
4290 	rwlock_init(&bond->curr_slave_lock);
4291 
4292 	bond->params = *params; /* copy params struct */
4293 
4294 	/* Initialize pointers */
4295 	bond->first_slave = NULL;
4296 	bond->curr_active_slave = NULL;
4297 	bond->current_arp_slave = NULL;
4298 	bond->primary_slave = NULL;
4299 	bond->dev = bond_dev;
4300 	INIT_LIST_HEAD(&bond->vlan_list);
4301 
4302 	/* Initialize the device entry points */
4303 	bond_dev->open = bond_open;
4304 	bond_dev->stop = bond_close;
4305 	bond_dev->get_stats = bond_get_stats;
4306 	bond_dev->do_ioctl = bond_do_ioctl;
4307 	bond_dev->ethtool_ops = &bond_ethtool_ops;
4308 	bond_dev->set_multicast_list = bond_set_multicast_list;
4309 	bond_dev->change_mtu = bond_change_mtu;
4310 	bond_dev->set_mac_address = bond_set_mac_address;
4311 
4312 	bond_set_mode_ops(bond, bond->params.mode);
4313 
4314 	bond_dev->destructor = free_netdev;
4315 
4316 	/* Initialize the device options */
4317 	bond_dev->tx_queue_len = 0;
4318 	bond_dev->flags |= IFF_MASTER|IFF_MULTICAST;
4319 	bond_dev->priv_flags |= IFF_BONDING;
4320 
4321 	/* At first, we block adding VLANs. That's the only way to
4322 	 * prevent problems that occur when adding VLANs over an
4323 	 * empty bond. The block will be removed once non-challenged
4324 	 * slaves are enslaved.
4325 	 */
4326 	bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
4327 
4328 	/* don't acquire bond device's netif_tx_lock when
4329 	 * transmitting */
4330 	bond_dev->features |= NETIF_F_LLTX;
4331 
4332 	/* By default, we declare the bond to be fully
4333 	 * VLAN hardware accelerated capable. Special
4334 	 * care is taken in the various xmit functions
4335 	 * when there are slaves that are not hw accel
4336 	 * capable
4337 	 */
4338 	bond_dev->vlan_rx_register = bond_vlan_rx_register;
4339 	bond_dev->vlan_rx_add_vid  = bond_vlan_rx_add_vid;
4340 	bond_dev->vlan_rx_kill_vid = bond_vlan_rx_kill_vid;
4341 	bond_dev->features |= (NETIF_F_HW_VLAN_TX |
4342 			       NETIF_F_HW_VLAN_RX |
4343 			       NETIF_F_HW_VLAN_FILTER);
4344 
4345 #ifdef CONFIG_PROC_FS
4346 	bond_create_proc_entry(bond);
4347 #endif
4348 
4349 	list_add_tail(&bond->bond_list, &bond_dev_list);
4350 
4351 	return 0;
4352 }
4353 
4354 /* De-initialize device specific data.
4355  * Caller must hold rtnl_lock.
4356  */
4357 void bond_deinit(struct net_device *bond_dev)
4358 {
4359 	struct bonding *bond = bond_dev->priv;
4360 
4361 	list_del(&bond->bond_list);
4362 
4363 #ifdef CONFIG_PROC_FS
4364 	bond_remove_proc_entry(bond);
4365 #endif
4366 }
4367 
4368 /* Unregister and free all bond devices.
4369  * Caller must hold rtnl_lock.
4370  */
4371 static void bond_free_all(void)
4372 {
4373 	struct bonding *bond, *nxt;
4374 
4375 	list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list) {
4376 		struct net_device *bond_dev = bond->dev;
4377 
4378 		bond_mc_list_destroy(bond);
4379 		/* Release the bonded slaves */
4380 		bond_release_all(bond_dev);
4381 		unregister_netdevice(bond_dev);
4382 		bond_deinit(bond_dev);
4383 	}
4384 
4385 #ifdef CONFIG_PROC_FS
4386 	bond_destroy_proc_dir();
4387 #endif
4388 }
4389 
4390 /*------------------------- Module initialization ---------------------------*/
4391 
4392 /*
4393  * Convert string input module parms.  Accept either the
4394  * number of the mode or its string name.
4395  */
4396 int bond_parse_parm(char *mode_arg, struct bond_parm_tbl *tbl)
4397 {
4398 	int i;
4399 
4400 	for (i = 0; tbl[i].modename; i++) {
4401 		if ((isdigit(*mode_arg) &&
4402 		     tbl[i].mode == simple_strtol(mode_arg, NULL, 0)) ||
4403 		    (strncmp(mode_arg, tbl[i].modename,
4404 			     strlen(tbl[i].modename)) == 0)) {
4405 			return tbl[i].mode;
4406 		}
4407 	}
4408 
4409 	return -1;
4410 }
4411 
4412 static int bond_check_params(struct bond_params *params)
4413 {
4414 	int arp_validate_value;
4415 
4416 	/*
4417 	 * Convert string parameters.
4418 	 */
4419 	if (mode) {
4420 		bond_mode = bond_parse_parm(mode, bond_mode_tbl);
4421 		if (bond_mode == -1) {
4422 			printk(KERN_ERR DRV_NAME
4423 			       ": Error: Invalid bonding mode \"%s\"\n",
4424 			       mode == NULL ? "NULL" : mode);
4425 			return -EINVAL;
4426 		}
4427 	}
4428 
4429 	if (xmit_hash_policy) {
4430 		if ((bond_mode != BOND_MODE_XOR) &&
4431 		    (bond_mode != BOND_MODE_8023AD)) {
4432 			printk(KERN_INFO DRV_NAME
4433 			       ": xor_mode param is irrelevant in mode %s\n",
4434 			       bond_mode_name(bond_mode));
4435 		} else {
4436 			xmit_hashtype = bond_parse_parm(xmit_hash_policy,
4437 							xmit_hashtype_tbl);
4438 			if (xmit_hashtype == -1) {
4439 				printk(KERN_ERR DRV_NAME
4440 			       	": Error: Invalid xmit_hash_policy \"%s\"\n",
4441 			       	xmit_hash_policy == NULL ? "NULL" :
4442 				       xmit_hash_policy);
4443 				return -EINVAL;
4444 			}
4445 		}
4446 	}
4447 
4448 	if (lacp_rate) {
4449 		if (bond_mode != BOND_MODE_8023AD) {
4450 			printk(KERN_INFO DRV_NAME
4451 			       ": lacp_rate param is irrelevant in mode %s\n",
4452 			       bond_mode_name(bond_mode));
4453 		} else {
4454 			lacp_fast = bond_parse_parm(lacp_rate, bond_lacp_tbl);
4455 			if (lacp_fast == -1) {
4456 				printk(KERN_ERR DRV_NAME
4457 				       ": Error: Invalid lacp rate \"%s\"\n",
4458 				       lacp_rate == NULL ? "NULL" : lacp_rate);
4459 				return -EINVAL;
4460 			}
4461 		}
4462 	}
4463 
4464 	if (max_bonds < 1 || max_bonds > INT_MAX) {
4465 		printk(KERN_WARNING DRV_NAME
4466 		       ": Warning: max_bonds (%d) not in range %d-%d, so it "
4467 		       "was reset to BOND_DEFAULT_MAX_BONDS (%d)\n",
4468 		       max_bonds, 1, INT_MAX, BOND_DEFAULT_MAX_BONDS);
4469 		max_bonds = BOND_DEFAULT_MAX_BONDS;
4470 	}
4471 
4472 	if (miimon < 0) {
4473 		printk(KERN_WARNING DRV_NAME
4474 		       ": Warning: miimon module parameter (%d), "
4475 		       "not in range 0-%d, so it was reset to %d\n",
4476 		       miimon, INT_MAX, BOND_LINK_MON_INTERV);
4477 		miimon = BOND_LINK_MON_INTERV;
4478 	}
4479 
4480 	if (updelay < 0) {
4481 		printk(KERN_WARNING DRV_NAME
4482 		       ": Warning: updelay module parameter (%d), "
4483 		       "not in range 0-%d, so it was reset to 0\n",
4484 		       updelay, INT_MAX);
4485 		updelay = 0;
4486 	}
4487 
4488 	if (downdelay < 0) {
4489 		printk(KERN_WARNING DRV_NAME
4490 		       ": Warning: downdelay module parameter (%d), "
4491 		       "not in range 0-%d, so it was reset to 0\n",
4492 		       downdelay, INT_MAX);
4493 		downdelay = 0;
4494 	}
4495 
4496 	if ((use_carrier != 0) && (use_carrier != 1)) {
4497 		printk(KERN_WARNING DRV_NAME
4498 		       ": Warning: use_carrier module parameter (%d), "
4499 		       "not of valid value (0/1), so it was set to 1\n",
4500 		       use_carrier);
4501 		use_carrier = 1;
4502 	}
4503 
4504 	/* reset values for 802.3ad */
4505 	if (bond_mode == BOND_MODE_8023AD) {
4506 		if (!miimon) {
4507 			printk(KERN_WARNING DRV_NAME
4508 			       ": Warning: miimon must be specified, "
4509 			       "otherwise bonding will not detect link "
4510 			       "failure, speed and duplex which are "
4511 			       "essential for 802.3ad operation\n");
4512 			printk(KERN_WARNING "Forcing miimon to 100msec\n");
4513 			miimon = 100;
4514 		}
4515 	}
4516 
4517 	/* reset values for TLB/ALB */
4518 	if ((bond_mode == BOND_MODE_TLB) ||
4519 	    (bond_mode == BOND_MODE_ALB)) {
4520 		if (!miimon) {
4521 			printk(KERN_WARNING DRV_NAME
4522 			       ": Warning: miimon must be specified, "
4523 			       "otherwise bonding will not detect link "
4524 			       "failure and link speed which are essential "
4525 			       "for TLB/ALB load balancing\n");
4526 			printk(KERN_WARNING "Forcing miimon to 100msec\n");
4527 			miimon = 100;
4528 		}
4529 	}
4530 
4531 	if (bond_mode == BOND_MODE_ALB) {
4532 		printk(KERN_NOTICE DRV_NAME
4533 		       ": In ALB mode you might experience client "
4534 		       "disconnections upon reconnection of a link if the "
4535 		       "bonding module updelay parameter (%d msec) is "
4536 		       "incompatible with the forwarding delay time of the "
4537 		       "switch\n",
4538 		       updelay);
4539 	}
4540 
4541 	if (!miimon) {
4542 		if (updelay || downdelay) {
4543 			/* just warn the user the up/down delay will have
4544 			 * no effect since miimon is zero...
4545 			 */
4546 			printk(KERN_WARNING DRV_NAME
4547 			       ": Warning: miimon module parameter not set "
4548 			       "and updelay (%d) or downdelay (%d) module "
4549 			       "parameter is set; updelay and downdelay have "
4550 			       "no effect unless miimon is set\n",
4551 			       updelay, downdelay);
4552 		}
4553 	} else {
4554 		/* don't allow arp monitoring */
4555 		if (arp_interval) {
4556 			printk(KERN_WARNING DRV_NAME
4557 			       ": Warning: miimon (%d) and arp_interval (%d) "
4558 			       "can't be used simultaneously, disabling ARP "
4559 			       "monitoring\n",
4560 			       miimon, arp_interval);
4561 			arp_interval = 0;
4562 		}
4563 
4564 		if ((updelay % miimon) != 0) {
4565 			printk(KERN_WARNING DRV_NAME
4566 			       ": Warning: updelay (%d) is not a multiple "
4567 			       "of miimon (%d), updelay rounded to %d ms\n",
4568 			       updelay, miimon, (updelay / miimon) * miimon);
4569 		}
4570 
4571 		updelay /= miimon;
4572 
4573 		if ((downdelay % miimon) != 0) {
4574 			printk(KERN_WARNING DRV_NAME
4575 			       ": Warning: downdelay (%d) is not a multiple "
4576 			       "of miimon (%d), downdelay rounded to %d ms\n",
4577 			       downdelay, miimon,
4578 			       (downdelay / miimon) * miimon);
4579 		}
4580 
4581 		downdelay /= miimon;
4582 	}
4583 
4584 	if (arp_interval < 0) {
4585 		printk(KERN_WARNING DRV_NAME
4586 		       ": Warning: arp_interval module parameter (%d) "
4587 		       ", not in range 0-%d, so it was reset to %d\n",
4588 		       arp_interval, INT_MAX, BOND_LINK_ARP_INTERV);
4589 		arp_interval = BOND_LINK_ARP_INTERV;
4590 	}
4591 
4592 	for (arp_ip_count = 0;
4593 	     (arp_ip_count < BOND_MAX_ARP_TARGETS) && arp_ip_target[arp_ip_count];
4594 	     arp_ip_count++) {
4595 		/* not complete check, but should be good enough to
4596 		   catch mistakes */
4597 		if (!isdigit(arp_ip_target[arp_ip_count][0])) {
4598 			printk(KERN_WARNING DRV_NAME
4599 			       ": Warning: bad arp_ip_target module parameter "
4600 			       "(%s), ARP monitoring will not be performed\n",
4601 			       arp_ip_target[arp_ip_count]);
4602 			arp_interval = 0;
4603 		} else {
4604 			u32 ip = in_aton(arp_ip_target[arp_ip_count]);
4605 			arp_target[arp_ip_count] = ip;
4606 		}
4607 	}
4608 
4609 	if (arp_interval && !arp_ip_count) {
4610 		/* don't allow arping if no arp_ip_target given... */
4611 		printk(KERN_WARNING DRV_NAME
4612 		       ": Warning: arp_interval module parameter (%d) "
4613 		       "specified without providing an arp_ip_target "
4614 		       "parameter, arp_interval was reset to 0\n",
4615 		       arp_interval);
4616 		arp_interval = 0;
4617 	}
4618 
4619 	if (arp_validate) {
4620 		if (bond_mode != BOND_MODE_ACTIVEBACKUP) {
4621 			printk(KERN_ERR DRV_NAME
4622 	       ": arp_validate only supported in active-backup mode\n");
4623 			return -EINVAL;
4624 		}
4625 		if (!arp_interval) {
4626 			printk(KERN_ERR DRV_NAME
4627 			       ": arp_validate requires arp_interval\n");
4628 			return -EINVAL;
4629 		}
4630 
4631 		arp_validate_value = bond_parse_parm(arp_validate,
4632 						     arp_validate_tbl);
4633 		if (arp_validate_value == -1) {
4634 			printk(KERN_ERR DRV_NAME
4635 			       ": Error: invalid arp_validate \"%s\"\n",
4636 			       arp_validate == NULL ? "NULL" : arp_validate);
4637 			return -EINVAL;
4638 		}
4639 	} else
4640 		arp_validate_value = 0;
4641 
4642 	if (miimon) {
4643 		printk(KERN_INFO DRV_NAME
4644 		       ": MII link monitoring set to %d ms\n",
4645 		       miimon);
4646 	} else if (arp_interval) {
4647 		int i;
4648 
4649 		printk(KERN_INFO DRV_NAME
4650 		       ": ARP monitoring set to %d ms, validate %s, with %d target(s):",
4651 		       arp_interval,
4652 		       arp_validate_tbl[arp_validate_value].modename,
4653 		       arp_ip_count);
4654 
4655 		for (i = 0; i < arp_ip_count; i++)
4656 			printk (" %s", arp_ip_target[i]);
4657 
4658 		printk("\n");
4659 
4660 	} else {
4661 		/* miimon and arp_interval not set, we need one so things
4662 		 * work as expected, see bonding.txt for details
4663 		 */
4664 		printk(KERN_WARNING DRV_NAME
4665 		       ": Warning: either miimon or arp_interval and "
4666 		       "arp_ip_target module parameters must be specified, "
4667 		       "otherwise bonding will not detect link failures! see "
4668 		       "bonding.txt for details.\n");
4669 	}
4670 
4671 	if (primary && !USES_PRIMARY(bond_mode)) {
4672 		/* currently, using a primary only makes sense
4673 		 * in active backup, TLB or ALB modes
4674 		 */
4675 		printk(KERN_WARNING DRV_NAME
4676 		       ": Warning: %s primary device specified but has no "
4677 		       "effect in %s mode\n",
4678 		       primary, bond_mode_name(bond_mode));
4679 		primary = NULL;
4680 	}
4681 
4682 	/* fill params struct with the proper values */
4683 	params->mode = bond_mode;
4684 	params->xmit_policy = xmit_hashtype;
4685 	params->miimon = miimon;
4686 	params->arp_interval = arp_interval;
4687 	params->arp_validate = arp_validate_value;
4688 	params->updelay = updelay;
4689 	params->downdelay = downdelay;
4690 	params->use_carrier = use_carrier;
4691 	params->lacp_fast = lacp_fast;
4692 	params->primary[0] = 0;
4693 
4694 	if (primary) {
4695 		strncpy(params->primary, primary, IFNAMSIZ);
4696 		params->primary[IFNAMSIZ - 1] = 0;
4697 	}
4698 
4699 	memcpy(params->arp_targets, arp_target, sizeof(arp_target));
4700 
4701 	return 0;
4702 }
4703 
4704 static struct lock_class_key bonding_netdev_xmit_lock_key;
4705 
4706 /* Create a new bond based on the specified name and bonding parameters.
4707  * If name is NULL, obtain a suitable "bond%d" name for us.
4708  * Caller must NOT hold rtnl_lock; we need to release it here before we
4709  * set up our sysfs entries.
4710  */
4711 int bond_create(char *name, struct bond_params *params, struct bonding **newbond)
4712 {
4713 	struct net_device *bond_dev;
4714 	int res;
4715 
4716 	rtnl_lock();
4717 	bond_dev = alloc_netdev(sizeof(struct bonding), name ? name : "",
4718 				ether_setup);
4719 	if (!bond_dev) {
4720 		printk(KERN_ERR DRV_NAME
4721 		       ": %s: eek! can't alloc netdev!\n",
4722 		       name);
4723 		res = -ENOMEM;
4724 		goto out_rtnl;
4725 	}
4726 
4727 	if (!name) {
4728 		res = dev_alloc_name(bond_dev, "bond%d");
4729 		if (res < 0)
4730 			goto out_netdev;
4731 	}
4732 
4733 	/* bond_init() must be called after dev_alloc_name() (for the
4734 	 * /proc files), but before register_netdevice(), because we
4735 	 * need to set function pointers.
4736 	 */
4737 
4738 	res = bond_init(bond_dev, params);
4739 	if (res < 0) {
4740 		goto out_netdev;
4741 	}
4742 
4743 	SET_MODULE_OWNER(bond_dev);
4744 
4745 	res = register_netdevice(bond_dev);
4746 	if (res < 0) {
4747 		goto out_bond;
4748 	}
4749 
4750 	lockdep_set_class(&bond_dev->_xmit_lock, &bonding_netdev_xmit_lock_key);
4751 
4752 	if (newbond)
4753 		*newbond = bond_dev->priv;
4754 
4755 	netif_carrier_off(bond_dev);
4756 
4757 	rtnl_unlock(); /* allows sysfs registration of net device */
4758 	res = bond_create_sysfs_entry(bond_dev->priv);
4759 	if (res < 0) {
4760 		rtnl_lock();
4761 		goto out_bond;
4762 	}
4763 
4764 	return 0;
4765 
4766 out_bond:
4767 	bond_deinit(bond_dev);
4768 out_netdev:
4769 	free_netdev(bond_dev);
4770 out_rtnl:
4771 	rtnl_unlock();
4772 	return res;
4773 }
4774 
4775 static int __init bonding_init(void)
4776 {
4777 	int i;
4778 	int res;
4779 
4780 	printk(KERN_INFO "%s", version);
4781 
4782 	res = bond_check_params(&bonding_defaults);
4783 	if (res) {
4784 		goto out;
4785 	}
4786 
4787 #ifdef CONFIG_PROC_FS
4788 	bond_create_proc_dir();
4789 #endif
4790 	for (i = 0; i < max_bonds; i++) {
4791 		res = bond_create(NULL, &bonding_defaults, NULL);
4792 		if (res)
4793 			goto err;
4794 	}
4795 
4796 	res = bond_create_sysfs();
4797 	if (res)
4798 		goto err;
4799 
4800 	register_netdevice_notifier(&bond_netdev_notifier);
4801 	register_inetaddr_notifier(&bond_inetaddr_notifier);
4802 
4803 	goto out;
4804 err:
4805 	rtnl_lock();
4806 	bond_free_all();
4807 	bond_destroy_sysfs();
4808 	rtnl_unlock();
4809 out:
4810 	return res;
4811 
4812 }
4813 
4814 static void __exit bonding_exit(void)
4815 {
4816 	unregister_netdevice_notifier(&bond_netdev_notifier);
4817 	unregister_inetaddr_notifier(&bond_inetaddr_notifier);
4818 
4819 	rtnl_lock();
4820 	bond_free_all();
4821 	bond_destroy_sysfs();
4822 	rtnl_unlock();
4823 }
4824 
4825 module_init(bonding_init);
4826 module_exit(bonding_exit);
4827 MODULE_LICENSE("GPL");
4828 MODULE_VERSION(DRV_VERSION);
4829 MODULE_DESCRIPTION(DRV_DESCRIPTION ", v" DRV_VERSION);
4830 MODULE_AUTHOR("Thomas Davis, tadavis@lbl.gov and many others");
4831 MODULE_SUPPORTED_DEVICE("most ethernet devices");
4832 
4833 /*
4834  * Local variables:
4835  *  c-indent-level: 8
4836  *  c-basic-offset: 8
4837  *  tab-width: 8
4838  * End:
4839  */
4840 
4841