xref: /linux/drivers/net/bonding/bond_3ad.c (revision 2d87650a3bf1b80f7d0d150ee1af3f8a89e5b7aa)
1 /*
2  * Copyright(c) 1999 - 2004 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of the GNU General Public License as published by the Free
6  * Software Foundation; either version 2 of the License, or (at your option)
7  * any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc., 59
16  * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
17  *
18  * The full GNU General Public License is included in this distribution in the
19  * file called LICENSE.
20  *
21  */
22 
23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24 
25 #include <linux/skbuff.h>
26 #include <linux/if_ether.h>
27 #include <linux/netdevice.h>
28 #include <linux/spinlock.h>
29 #include <linux/ethtool.h>
30 #include <linux/etherdevice.h>
31 #include <linux/if_bonding.h>
32 #include <linux/pkt_sched.h>
33 #include <net/net_namespace.h>
34 #include "bonding.h"
35 #include "bond_3ad.h"
36 
37 // General definitions
38 #define AD_SHORT_TIMEOUT           1
39 #define AD_LONG_TIMEOUT            0
40 #define AD_STANDBY                 0x2
41 #define AD_MAX_TX_IN_SECOND        3
42 #define AD_COLLECTOR_MAX_DELAY     0
43 
44 // Timer definitions(43.4.4 in the 802.3ad standard)
45 #define AD_FAST_PERIODIC_TIME      1
46 #define AD_SLOW_PERIODIC_TIME      30
47 #define AD_SHORT_TIMEOUT_TIME      (3*AD_FAST_PERIODIC_TIME)
48 #define AD_LONG_TIMEOUT_TIME       (3*AD_SLOW_PERIODIC_TIME)
49 #define AD_CHURN_DETECTION_TIME    60
50 #define AD_AGGREGATE_WAIT_TIME     2
51 
52 // Port state definitions(43.4.2.2 in the 802.3ad standard)
53 #define AD_STATE_LACP_ACTIVITY   0x1
54 #define AD_STATE_LACP_TIMEOUT    0x2
55 #define AD_STATE_AGGREGATION     0x4
56 #define AD_STATE_SYNCHRONIZATION 0x8
57 #define AD_STATE_COLLECTING      0x10
58 #define AD_STATE_DISTRIBUTING    0x20
59 #define AD_STATE_DEFAULTED       0x40
60 #define AD_STATE_EXPIRED         0x80
61 
62 // Port Variables definitions used by the State Machines(43.4.7 in the 802.3ad standard)
63 #define AD_PORT_BEGIN           0x1
64 #define AD_PORT_LACP_ENABLED    0x2
65 #define AD_PORT_ACTOR_CHURN     0x4
66 #define AD_PORT_PARTNER_CHURN   0x8
67 #define AD_PORT_READY           0x10
68 #define AD_PORT_READY_N         0x20
69 #define AD_PORT_MATCHED         0x40
70 #define AD_PORT_STANDBY         0x80
71 #define AD_PORT_SELECTED        0x100
72 #define AD_PORT_MOVED           0x200
73 
74 // Port Key definitions
75 // key is determined according to the link speed, duplex and
76 // user key(which is yet not supported)
77 //              ------------------------------------------------------------
78 // Port key :   | User key                       |      Speed       |Duplex|
79 //              ------------------------------------------------------------
80 //              16                               6               1 0
81 #define  AD_DUPLEX_KEY_BITS    0x1
82 #define  AD_SPEED_KEY_BITS     0x3E
83 #define  AD_USER_KEY_BITS      0xFFC0
84 
85 //dalloun
86 #define     AD_LINK_SPEED_BITMASK_1MBPS       0x1
87 #define     AD_LINK_SPEED_BITMASK_10MBPS      0x2
88 #define     AD_LINK_SPEED_BITMASK_100MBPS     0x4
89 #define     AD_LINK_SPEED_BITMASK_1000MBPS    0x8
90 #define     AD_LINK_SPEED_BITMASK_10000MBPS   0x10
91 //endalloun
92 
93 // compare MAC addresses
94 #define MAC_ADDRESS_COMPARE(A, B) memcmp(A, B, ETH_ALEN)
95 
96 static struct mac_addr null_mac_addr = { { 0, 0, 0, 0, 0, 0 } };
97 static u16 ad_ticks_per_sec;
98 static const int ad_delta_in_ticks = (AD_TIMER_INTERVAL * HZ) / 1000;
99 
100 static const u8 lacpdu_mcast_addr[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
101 
102 // ================= main 802.3ad protocol functions ==================
103 static int ad_lacpdu_send(struct port *port);
104 static int ad_marker_send(struct port *port, struct bond_marker *marker);
105 static void ad_mux_machine(struct port *port);
106 static void ad_rx_machine(struct lacpdu *lacpdu, struct port *port);
107 static void ad_tx_machine(struct port *port);
108 static void ad_periodic_machine(struct port *port);
109 static void ad_port_selection_logic(struct port *port);
110 static void ad_agg_selection_logic(struct aggregator *aggregator);
111 static void ad_clear_agg(struct aggregator *aggregator);
112 static void ad_initialize_agg(struct aggregator *aggregator);
113 static void ad_initialize_port(struct port *port, int lacp_fast);
114 static void ad_enable_collecting_distributing(struct port *port);
115 static void ad_disable_collecting_distributing(struct port *port);
116 static void ad_marker_info_received(struct bond_marker *marker_info, struct port *port);
117 static void ad_marker_response_received(struct bond_marker *marker, struct port *port);
118 
119 
120 /////////////////////////////////////////////////////////////////////////////////
121 // ================= api to bonding and kernel code ==================
122 /////////////////////////////////////////////////////////////////////////////////
123 
124 /**
125  * __get_bond_by_port - get the port's bonding struct
126  * @port: the port we're looking at
127  *
128  * Return @port's bonding struct, or %NULL if it can't be found.
129  */
130 static inline struct bonding *__get_bond_by_port(struct port *port)
131 {
132 	if (port->slave == NULL)
133 		return NULL;
134 
135 	return bond_get_bond_by_slave(port->slave);
136 }
137 
138 /**
139  * __get_first_agg - get the first aggregator in the bond
140  * @bond: the bond we're looking at
141  *
142  * Return the aggregator of the first slave in @bond, or %NULL if it can't be
143  * found.
144  */
145 static inline struct aggregator *__get_first_agg(struct port *port)
146 {
147 	struct bonding *bond = __get_bond_by_port(port);
148 	struct slave *first_slave;
149 
150 	/* If there's no bond for this port, or bond has no slaves */
151 	if (bond == NULL)
152 		return NULL;
153 	rcu_read_lock();
154 	first_slave = bond_first_slave_rcu(bond);
155 	rcu_read_unlock();
156 	return first_slave ? &(SLAVE_AD_INFO(first_slave).aggregator) : NULL;
157 }
158 
159 /*
160  * __agg_has_partner
161  *
162  * Return nonzero if aggregator has a partner (denoted by a non-zero ether
163  * address for the partner).  Return 0 if not.
164  */
165 static inline int __agg_has_partner(struct aggregator *agg)
166 {
167 	return !is_zero_ether_addr(agg->partner_system.mac_addr_value);
168 }
169 
170 /**
171  * __disable_port - disable the port's slave
172  * @port: the port we're looking at
173  *
174  */
175 static inline void __disable_port(struct port *port)
176 {
177 	bond_set_slave_inactive_flags(port->slave);
178 }
179 
180 /**
181  * __enable_port - enable the port's slave, if it's up
182  * @port: the port we're looking at
183  *
184  */
185 static inline void __enable_port(struct port *port)
186 {
187 	struct slave *slave = port->slave;
188 
189 	if ((slave->link == BOND_LINK_UP) && IS_UP(slave->dev))
190 		bond_set_slave_active_flags(slave);
191 }
192 
193 /**
194  * __port_is_enabled - check if the port's slave is in active state
195  * @port: the port we're looking at
196  *
197  */
198 static inline int __port_is_enabled(struct port *port)
199 {
200 	return bond_is_active_slave(port->slave);
201 }
202 
203 /**
204  * __get_agg_selection_mode - get the aggregator selection mode
205  * @port: the port we're looking at
206  *
207  * Get the aggregator selection mode. Can be %STABLE, %BANDWIDTH or %COUNT.
208  */
209 static inline u32 __get_agg_selection_mode(struct port *port)
210 {
211 	struct bonding *bond = __get_bond_by_port(port);
212 
213 	if (bond == NULL)
214 		return BOND_AD_STABLE;
215 
216 	return bond->params.ad_select;
217 }
218 
219 /**
220  * __check_agg_selection_timer - check if the selection timer has expired
221  * @port: the port we're looking at
222  *
223  */
224 static inline int __check_agg_selection_timer(struct port *port)
225 {
226 	struct bonding *bond = __get_bond_by_port(port);
227 
228 	if (bond == NULL)
229 		return 0;
230 
231 	return BOND_AD_INFO(bond).agg_select_timer ? 1 : 0;
232 }
233 
234 /**
235  * __get_state_machine_lock - lock the port's state machines
236  * @port: the port we're looking at
237  *
238  */
239 static inline void __get_state_machine_lock(struct port *port)
240 {
241 	spin_lock_bh(&(SLAVE_AD_INFO(port->slave).state_machine_lock));
242 }
243 
244 /**
245  * __release_state_machine_lock - unlock the port's state machines
246  * @port: the port we're looking at
247  *
248  */
249 static inline void __release_state_machine_lock(struct port *port)
250 {
251 	spin_unlock_bh(&(SLAVE_AD_INFO(port->slave).state_machine_lock));
252 }
253 
254 /**
255  * __get_link_speed - get a port's speed
256  * @port: the port we're looking at
257  *
258  * Return @port's speed in 802.3ad bitmask format. i.e. one of:
259  *     0,
260  *     %AD_LINK_SPEED_BITMASK_10MBPS,
261  *     %AD_LINK_SPEED_BITMASK_100MBPS,
262  *     %AD_LINK_SPEED_BITMASK_1000MBPS,
263  *     %AD_LINK_SPEED_BITMASK_10000MBPS
264  */
265 static u16 __get_link_speed(struct port *port)
266 {
267 	struct slave *slave = port->slave;
268 	u16 speed;
269 
270 	/* this if covers only a special case: when the configuration starts with
271 	 * link down, it sets the speed to 0.
272 	 * This is done in spite of the fact that the e100 driver reports 0 to be
273 	 * compatible with MVT in the future.*/
274 	if (slave->link != BOND_LINK_UP)
275 		speed = 0;
276 	else {
277 		switch (slave->speed) {
278 		case SPEED_10:
279 			speed = AD_LINK_SPEED_BITMASK_10MBPS;
280 			break;
281 
282 		case SPEED_100:
283 			speed = AD_LINK_SPEED_BITMASK_100MBPS;
284 			break;
285 
286 		case SPEED_1000:
287 			speed = AD_LINK_SPEED_BITMASK_1000MBPS;
288 			break;
289 
290 		case SPEED_10000:
291 			speed = AD_LINK_SPEED_BITMASK_10000MBPS;
292 			break;
293 
294 		default:
295 			speed = 0; // unknown speed value from ethtool. shouldn't happen
296 			break;
297 		}
298 	}
299 
300 	pr_debug("Port %d Received link speed %d update from adapter\n",
301 		 port->actor_port_number, speed);
302 	return speed;
303 }
304 
305 /**
306  * __get_duplex - get a port's duplex
307  * @port: the port we're looking at
308  *
309  * Return @port's duplex in 802.3ad bitmask format. i.e.:
310  *     0x01 if in full duplex
311  *     0x00 otherwise
312  */
313 static u8 __get_duplex(struct port *port)
314 {
315 	struct slave *slave = port->slave;
316 
317 	u8 retval;
318 
319 	//  handling a special case: when the configuration starts with
320 	// link down, it sets the duplex to 0.
321 	if (slave->link != BOND_LINK_UP)
322 		retval = 0x0;
323 	else {
324 		switch (slave->duplex) {
325 		case DUPLEX_FULL:
326 			retval = 0x1;
327 			pr_debug("Port %d Received status full duplex update from adapter\n",
328 				 port->actor_port_number);
329 			break;
330 		case DUPLEX_HALF:
331 		default:
332 			retval = 0x0;
333 			pr_debug("Port %d Received status NOT full duplex update from adapter\n",
334 				 port->actor_port_number);
335 			break;
336 		}
337 	}
338 	return retval;
339 }
340 
341 /**
342  * __initialize_port_locks - initialize a port's STATE machine spinlock
343  * @port: the slave of the port we're looking at
344  *
345  */
346 static inline void __initialize_port_locks(struct slave *slave)
347 {
348 	// make sure it isn't called twice
349 	spin_lock_init(&(SLAVE_AD_INFO(slave).state_machine_lock));
350 }
351 
352 //conversions
353 
354 /**
355  * __ad_timer_to_ticks - convert a given timer type to AD module ticks
356  * @timer_type:	which timer to operate
357  * @par: timer parameter. see below
358  *
359  * If @timer_type is %current_while_timer, @par indicates long/short timer.
360  * If @timer_type is %periodic_timer, @par is one of %FAST_PERIODIC_TIME,
361  *						    %SLOW_PERIODIC_TIME.
362  */
363 static u16 __ad_timer_to_ticks(u16 timer_type, u16 par)
364 {
365 	u16 retval = 0; /* to silence the compiler */
366 
367 	switch (timer_type) {
368 	case AD_CURRENT_WHILE_TIMER:   // for rx machine usage
369 		if (par)
370 			retval = (AD_SHORT_TIMEOUT_TIME*ad_ticks_per_sec); // short timeout
371 		else
372 			retval = (AD_LONG_TIMEOUT_TIME*ad_ticks_per_sec); // long timeout
373 		break;
374 	case AD_ACTOR_CHURN_TIMER:	    // for local churn machine
375 		retval = (AD_CHURN_DETECTION_TIME*ad_ticks_per_sec);
376 		break;
377 	case AD_PERIODIC_TIMER:	    // for periodic machine
378 		retval = (par*ad_ticks_per_sec); // long timeout
379 		break;
380 	case AD_PARTNER_CHURN_TIMER:   // for remote churn machine
381 		retval = (AD_CHURN_DETECTION_TIME*ad_ticks_per_sec);
382 		break;
383 	case AD_WAIT_WHILE_TIMER:	    // for selection machine
384 		retval = (AD_AGGREGATE_WAIT_TIME*ad_ticks_per_sec);
385 		break;
386 	}
387 	return retval;
388 }
389 
390 
391 /////////////////////////////////////////////////////////////////////////////////
392 // ================= ad_rx_machine helper functions ==================
393 /////////////////////////////////////////////////////////////////////////////////
394 
395 /**
396  * __choose_matched - update a port's matched variable from a received lacpdu
397  * @lacpdu: the lacpdu we've received
398  * @port: the port we're looking at
399  *
400  * Update the value of the matched variable, using parameter values from a
401  * newly received lacpdu. Parameter values for the partner carried in the
402  * received PDU are compared with the corresponding operational parameter
403  * values for the actor. Matched is set to TRUE if all of these parameters
404  * match and the PDU parameter partner_state.aggregation has the same value as
405  * actor_oper_port_state.aggregation and lacp will actively maintain the link
406  * in the aggregation. Matched is also set to TRUE if the value of
407  * actor_state.aggregation in the received PDU is set to FALSE, i.e., indicates
408  * an individual link and lacp will actively maintain the link. Otherwise,
409  * matched is set to FALSE. LACP is considered to be actively maintaining the
410  * link if either the PDU's actor_state.lacp_activity variable is TRUE or both
411  * the actor's actor_oper_port_state.lacp_activity and the PDU's
412  * partner_state.lacp_activity variables are TRUE.
413  *
414  * Note: the AD_PORT_MATCHED "variable" is not specified by 802.3ad; it is
415  * used here to implement the language from 802.3ad 43.4.9 that requires
416  * recordPDU to "match" the LACPDU parameters to the stored values.
417  */
418 static void __choose_matched(struct lacpdu *lacpdu, struct port *port)
419 {
420 	// check if all parameters are alike
421 	if (((ntohs(lacpdu->partner_port) == port->actor_port_number) &&
422 	     (ntohs(lacpdu->partner_port_priority) == port->actor_port_priority) &&
423 	     !MAC_ADDRESS_COMPARE(&(lacpdu->partner_system), &(port->actor_system)) &&
424 	     (ntohs(lacpdu->partner_system_priority) == port->actor_system_priority) &&
425 	     (ntohs(lacpdu->partner_key) == port->actor_oper_port_key) &&
426 	     ((lacpdu->partner_state & AD_STATE_AGGREGATION) == (port->actor_oper_port_state & AD_STATE_AGGREGATION))) ||
427 	    // or this is individual link(aggregation == FALSE)
428 	    ((lacpdu->actor_state & AD_STATE_AGGREGATION) == 0)
429 		) {
430 		// update the state machine Matched variable
431 		port->sm_vars |= AD_PORT_MATCHED;
432 	} else {
433 		port->sm_vars &= ~AD_PORT_MATCHED;
434 	}
435 }
436 
437 /**
438  * __record_pdu - record parameters from a received lacpdu
439  * @lacpdu: the lacpdu we've received
440  * @port: the port we're looking at
441  *
442  * Record the parameter values for the Actor carried in a received lacpdu as
443  * the current partner operational parameter values and sets
444  * actor_oper_port_state.defaulted to FALSE.
445  */
446 static void __record_pdu(struct lacpdu *lacpdu, struct port *port)
447 {
448 	if (lacpdu && port) {
449 		struct port_params *partner = &port->partner_oper;
450 
451 		__choose_matched(lacpdu, port);
452 		// record the new parameter values for the partner operational
453 		partner->port_number = ntohs(lacpdu->actor_port);
454 		partner->port_priority = ntohs(lacpdu->actor_port_priority);
455 		partner->system = lacpdu->actor_system;
456 		partner->system_priority = ntohs(lacpdu->actor_system_priority);
457 		partner->key = ntohs(lacpdu->actor_key);
458 		partner->port_state = lacpdu->actor_state;
459 
460 		// set actor_oper_port_state.defaulted to FALSE
461 		port->actor_oper_port_state &= ~AD_STATE_DEFAULTED;
462 
463 		// set the partner sync. to on if the partner is sync. and the port is matched
464 		if ((port->sm_vars & AD_PORT_MATCHED)
465 		    && (lacpdu->actor_state & AD_STATE_SYNCHRONIZATION))
466 			partner->port_state |= AD_STATE_SYNCHRONIZATION;
467 		else
468 			partner->port_state &= ~AD_STATE_SYNCHRONIZATION;
469 	}
470 }
471 
472 /**
473  * __record_default - record default parameters
474  * @port: the port we're looking at
475  *
476  * This function records the default parameter values for the partner carried
477  * in the Partner Admin parameters as the current partner operational parameter
478  * values and sets actor_oper_port_state.defaulted to TRUE.
479  */
480 static void __record_default(struct port *port)
481 {
482 	if (port) {
483 		// record the partner admin parameters
484 		memcpy(&port->partner_oper, &port->partner_admin,
485 		       sizeof(struct port_params));
486 
487 		// set actor_oper_port_state.defaulted to true
488 		port->actor_oper_port_state |= AD_STATE_DEFAULTED;
489 	}
490 }
491 
492 /**
493  * __update_selected - update a port's Selected variable from a received lacpdu
494  * @lacpdu: the lacpdu we've received
495  * @port: the port we're looking at
496  *
497  * Update the value of the selected variable, using parameter values from a
498  * newly received lacpdu. The parameter values for the Actor carried in the
499  * received PDU are compared with the corresponding operational parameter
500  * values for the ports partner. If one or more of the comparisons shows that
501  * the value(s) received in the PDU differ from the current operational values,
502  * then selected is set to FALSE and actor_oper_port_state.synchronization is
503  * set to out_of_sync. Otherwise, selected remains unchanged.
504  */
505 static void __update_selected(struct lacpdu *lacpdu, struct port *port)
506 {
507 	if (lacpdu && port) {
508 		const struct port_params *partner = &port->partner_oper;
509 
510 		// check if any parameter is different
511 		if (ntohs(lacpdu->actor_port) != partner->port_number ||
512 		    ntohs(lacpdu->actor_port_priority) != partner->port_priority ||
513 		    MAC_ADDRESS_COMPARE(&lacpdu->actor_system, &partner->system) ||
514 		    ntohs(lacpdu->actor_system_priority) != partner->system_priority ||
515 		    ntohs(lacpdu->actor_key) != partner->key ||
516 		    (lacpdu->actor_state & AD_STATE_AGGREGATION) != (partner->port_state & AD_STATE_AGGREGATION)) {
517 			// update the state machine Selected variable
518 			port->sm_vars &= ~AD_PORT_SELECTED;
519 		}
520 	}
521 }
522 
523 /**
524  * __update_default_selected - update a port's Selected variable from Partner
525  * @port: the port we're looking at
526  *
527  * This function updates the value of the selected variable, using the partner
528  * administrative parameter values. The administrative values are compared with
529  * the corresponding operational parameter values for the partner. If one or
530  * more of the comparisons shows that the administrative value(s) differ from
531  * the current operational values, then Selected is set to FALSE and
532  * actor_oper_port_state.synchronization is set to OUT_OF_SYNC. Otherwise,
533  * Selected remains unchanged.
534  */
535 static void __update_default_selected(struct port *port)
536 {
537 	if (port) {
538 		const struct port_params *admin = &port->partner_admin;
539 		const struct port_params *oper = &port->partner_oper;
540 
541 		// check if any parameter is different
542 		if (admin->port_number != oper->port_number ||
543 		    admin->port_priority != oper->port_priority ||
544 		    MAC_ADDRESS_COMPARE(&admin->system, &oper->system) ||
545 		    admin->system_priority != oper->system_priority ||
546 		    admin->key != oper->key ||
547 		    (admin->port_state & AD_STATE_AGGREGATION)
548 			!= (oper->port_state & AD_STATE_AGGREGATION)) {
549 			// update the state machine Selected variable
550 			port->sm_vars &= ~AD_PORT_SELECTED;
551 		}
552 	}
553 }
554 
555 /**
556  * __update_ntt - update a port's ntt variable from a received lacpdu
557  * @lacpdu: the lacpdu we've received
558  * @port: the port we're looking at
559  *
560  * Updates the value of the ntt variable, using parameter values from a newly
561  * received lacpdu. The parameter values for the partner carried in the
562  * received PDU are compared with the corresponding operational parameter
563  * values for the Actor. If one or more of the comparisons shows that the
564  * value(s) received in the PDU differ from the current operational values,
565  * then ntt is set to TRUE. Otherwise, ntt remains unchanged.
566  */
567 static void __update_ntt(struct lacpdu *lacpdu, struct port *port)
568 {
569 	// validate lacpdu and port
570 	if (lacpdu && port) {
571 		// check if any parameter is different
572 		if ((ntohs(lacpdu->partner_port) != port->actor_port_number) ||
573 		    (ntohs(lacpdu->partner_port_priority) != port->actor_port_priority) ||
574 		    MAC_ADDRESS_COMPARE(&(lacpdu->partner_system), &(port->actor_system)) ||
575 		    (ntohs(lacpdu->partner_system_priority) != port->actor_system_priority) ||
576 		    (ntohs(lacpdu->partner_key) != port->actor_oper_port_key) ||
577 		    ((lacpdu->partner_state & AD_STATE_LACP_ACTIVITY) != (port->actor_oper_port_state & AD_STATE_LACP_ACTIVITY)) ||
578 		    ((lacpdu->partner_state & AD_STATE_LACP_TIMEOUT) != (port->actor_oper_port_state & AD_STATE_LACP_TIMEOUT)) ||
579 		    ((lacpdu->partner_state & AD_STATE_SYNCHRONIZATION) != (port->actor_oper_port_state & AD_STATE_SYNCHRONIZATION)) ||
580 		    ((lacpdu->partner_state & AD_STATE_AGGREGATION) != (port->actor_oper_port_state & AD_STATE_AGGREGATION))
581 		   ) {
582 
583 			port->ntt = true;
584 		}
585 	}
586 }
587 
588 /**
589  * __attach_bond_to_agg
590  * @port: the port we're looking at
591  *
592  * Handle the attaching of the port's control parser/multiplexer and the
593  * aggregator. This function does nothing since the parser/multiplexer of the
594  * receive and the parser/multiplexer of the aggregator are already combined.
595  */
596 static void __attach_bond_to_agg(struct port *port)
597 {
598 	port = NULL; /* just to satisfy the compiler */
599 	// This function does nothing since the parser/multiplexer of the receive
600 	// and the parser/multiplexer of the aggregator are already combined
601 }
602 
603 /**
604  * __detach_bond_from_agg
605  * @port: the port we're looking at
606  *
607  * Handle the detaching of the port's control parser/multiplexer from the
608  * aggregator. This function does nothing since the parser/multiplexer of the
609  * receive and the parser/multiplexer of the aggregator are already combined.
610  */
611 static void __detach_bond_from_agg(struct port *port)
612 {
613 	port = NULL; /* just to satisfy the compiler */
614 	// This function does nothing since the parser/multiplexer of the receive
615 	// and the parser/multiplexer of the aggregator are already combined
616 }
617 
618 /**
619  * __agg_ports_are_ready - check if all ports in an aggregator are ready
620  * @aggregator: the aggregator we're looking at
621  *
622  */
623 static int __agg_ports_are_ready(struct aggregator *aggregator)
624 {
625 	struct port *port;
626 	int retval = 1;
627 
628 	if (aggregator) {
629 		// scan all ports in this aggregator to verfy if they are all ready
630 		for (port = aggregator->lag_ports;
631 		     port;
632 		     port = port->next_port_in_aggregator) {
633 			if (!(port->sm_vars & AD_PORT_READY_N)) {
634 				retval = 0;
635 				break;
636 			}
637 		}
638 	}
639 
640 	return retval;
641 }
642 
643 /**
644  * __set_agg_ports_ready - set value of Ready bit in all ports of an aggregator
645  * @aggregator: the aggregator we're looking at
646  * @val: Should the ports' ready bit be set on or off
647  *
648  */
649 static void __set_agg_ports_ready(struct aggregator *aggregator, int val)
650 {
651 	struct port *port;
652 
653 	for (port = aggregator->lag_ports; port;
654 	     port = port->next_port_in_aggregator) {
655 		if (val)
656 			port->sm_vars |= AD_PORT_READY;
657 		else
658 			port->sm_vars &= ~AD_PORT_READY;
659 	}
660 }
661 
662 /**
663  * __get_agg_bandwidth - get the total bandwidth of an aggregator
664  * @aggregator: the aggregator we're looking at
665  *
666  */
667 static u32 __get_agg_bandwidth(struct aggregator *aggregator)
668 {
669 	u32 bandwidth = 0;
670 
671 	if (aggregator->num_of_ports) {
672 		switch (__get_link_speed(aggregator->lag_ports)) {
673 		case AD_LINK_SPEED_BITMASK_1MBPS:
674 			bandwidth = aggregator->num_of_ports;
675 			break;
676 		case AD_LINK_SPEED_BITMASK_10MBPS:
677 			bandwidth = aggregator->num_of_ports * 10;
678 			break;
679 		case AD_LINK_SPEED_BITMASK_100MBPS:
680 			bandwidth = aggregator->num_of_ports * 100;
681 			break;
682 		case AD_LINK_SPEED_BITMASK_1000MBPS:
683 			bandwidth = aggregator->num_of_ports * 1000;
684 			break;
685 		case AD_LINK_SPEED_BITMASK_10000MBPS:
686 			bandwidth = aggregator->num_of_ports * 10000;
687 			break;
688 		default:
689 			bandwidth = 0; /*to silence the compiler ....*/
690 		}
691 	}
692 	return bandwidth;
693 }
694 
695 /**
696  * __get_active_agg - get the current active aggregator
697  * @aggregator: the aggregator we're looking at
698  *
699  */
700 static struct aggregator *__get_active_agg(struct aggregator *aggregator)
701 {
702 	struct bonding *bond = aggregator->slave->bond;
703 	struct list_head *iter;
704 	struct slave *slave;
705 
706 	rcu_read_lock();
707 	bond_for_each_slave_rcu(bond, slave, iter)
708 		if (SLAVE_AD_INFO(slave).aggregator.is_active) {
709 			rcu_read_unlock();
710 			return &(SLAVE_AD_INFO(slave).aggregator);
711 		}
712 	rcu_read_unlock();
713 
714 	return NULL;
715 }
716 
717 /**
718  * __update_lacpdu_from_port - update a port's lacpdu fields
719  * @port: the port we're looking at
720  *
721  */
722 static inline void __update_lacpdu_from_port(struct port *port)
723 {
724 	struct lacpdu *lacpdu = &port->lacpdu;
725 	const struct port_params *partner = &port->partner_oper;
726 
727 	/* update current actual Actor parameters */
728 	/* lacpdu->subtype                   initialized
729 	 * lacpdu->version_number            initialized
730 	 * lacpdu->tlv_type_actor_info       initialized
731 	 * lacpdu->actor_information_length  initialized
732 	 */
733 
734 	lacpdu->actor_system_priority = htons(port->actor_system_priority);
735 	lacpdu->actor_system = port->actor_system;
736 	lacpdu->actor_key = htons(port->actor_oper_port_key);
737 	lacpdu->actor_port_priority = htons(port->actor_port_priority);
738 	lacpdu->actor_port = htons(port->actor_port_number);
739 	lacpdu->actor_state = port->actor_oper_port_state;
740 
741 	/* lacpdu->reserved_3_1              initialized
742 	 * lacpdu->tlv_type_partner_info     initialized
743 	 * lacpdu->partner_information_length initialized
744 	 */
745 
746 	lacpdu->partner_system_priority = htons(partner->system_priority);
747 	lacpdu->partner_system = partner->system;
748 	lacpdu->partner_key = htons(partner->key);
749 	lacpdu->partner_port_priority = htons(partner->port_priority);
750 	lacpdu->partner_port = htons(partner->port_number);
751 	lacpdu->partner_state = partner->port_state;
752 
753 	/* lacpdu->reserved_3_2              initialized
754 	 * lacpdu->tlv_type_collector_info   initialized
755 	 * lacpdu->collector_information_length initialized
756 	 * collector_max_delay                initialized
757 	 * reserved_12[12]                   initialized
758 	 * tlv_type_terminator               initialized
759 	 * terminator_length                 initialized
760 	 * reserved_50[50]                   initialized
761 	 */
762 }
763 
764 //////////////////////////////////////////////////////////////////////////////////////
765 // ================= main 802.3ad protocol code ======================================
766 //////////////////////////////////////////////////////////////////////////////////////
767 
768 /**
769  * ad_lacpdu_send - send out a lacpdu packet on a given port
770  * @port: the port we're looking at
771  *
772  * Returns:   0 on success
773  *          < 0 on error
774  */
775 static int ad_lacpdu_send(struct port *port)
776 {
777 	struct slave *slave = port->slave;
778 	struct sk_buff *skb;
779 	struct lacpdu_header *lacpdu_header;
780 	int length = sizeof(struct lacpdu_header);
781 
782 	skb = dev_alloc_skb(length);
783 	if (!skb)
784 		return -ENOMEM;
785 
786 	skb->dev = slave->dev;
787 	skb_reset_mac_header(skb);
788 	skb->network_header = skb->mac_header + ETH_HLEN;
789 	skb->protocol = PKT_TYPE_LACPDU;
790 	skb->priority = TC_PRIO_CONTROL;
791 
792 	lacpdu_header = (struct lacpdu_header *)skb_put(skb, length);
793 
794 	memcpy(lacpdu_header->hdr.h_dest, lacpdu_mcast_addr, ETH_ALEN);
795 	/* Note: source address is set to be the member's PERMANENT address,
796 	   because we use it to identify loopback lacpdus in receive. */
797 	memcpy(lacpdu_header->hdr.h_source, slave->perm_hwaddr, ETH_ALEN);
798 	lacpdu_header->hdr.h_proto = PKT_TYPE_LACPDU;
799 
800 	lacpdu_header->lacpdu = port->lacpdu; // struct copy
801 
802 	dev_queue_xmit(skb);
803 
804 	return 0;
805 }
806 
807 /**
808  * ad_marker_send - send marker information/response on a given port
809  * @port: the port we're looking at
810  * @marker: marker data to send
811  *
812  * Returns:   0 on success
813  *          < 0 on error
814  */
815 static int ad_marker_send(struct port *port, struct bond_marker *marker)
816 {
817 	struct slave *slave = port->slave;
818 	struct sk_buff *skb;
819 	struct bond_marker_header *marker_header;
820 	int length = sizeof(struct bond_marker_header);
821 
822 	skb = dev_alloc_skb(length + 16);
823 	if (!skb)
824 		return -ENOMEM;
825 
826 	skb_reserve(skb, 16);
827 
828 	skb->dev = slave->dev;
829 	skb_reset_mac_header(skb);
830 	skb->network_header = skb->mac_header + ETH_HLEN;
831 	skb->protocol = PKT_TYPE_LACPDU;
832 
833 	marker_header = (struct bond_marker_header *)skb_put(skb, length);
834 
835 	memcpy(marker_header->hdr.h_dest, lacpdu_mcast_addr, ETH_ALEN);
836 	/* Note: source address is set to be the member's PERMANENT address,
837 	   because we use it to identify loopback MARKERs in receive. */
838 	memcpy(marker_header->hdr.h_source, slave->perm_hwaddr, ETH_ALEN);
839 	marker_header->hdr.h_proto = PKT_TYPE_LACPDU;
840 
841 	marker_header->marker = *marker; // struct copy
842 
843 	dev_queue_xmit(skb);
844 
845 	return 0;
846 }
847 
848 /**
849  * ad_mux_machine - handle a port's mux state machine
850  * @port: the port we're looking at
851  *
852  */
853 static void ad_mux_machine(struct port *port)
854 {
855 	mux_states_t last_state;
856 
857 	// keep current State Machine state to compare later if it was changed
858 	last_state = port->sm_mux_state;
859 
860 	if (port->sm_vars & AD_PORT_BEGIN) {
861 		port->sm_mux_state = AD_MUX_DETACHED;		 // next state
862 	} else {
863 		switch (port->sm_mux_state) {
864 		case AD_MUX_DETACHED:
865 			if ((port->sm_vars & AD_PORT_SELECTED)
866 			    || (port->sm_vars & AD_PORT_STANDBY))
867 				/* if SELECTED or STANDBY */
868 				port->sm_mux_state = AD_MUX_WAITING; // next state
869 			break;
870 		case AD_MUX_WAITING:
871 			// if SELECTED == FALSE return to DETACH state
872 			if (!(port->sm_vars & AD_PORT_SELECTED)) { // if UNSELECTED
873 				port->sm_vars &= ~AD_PORT_READY_N;
874 				// in order to withhold the Selection Logic to check all ports READY_N value
875 				// every callback cycle to update ready variable, we check READY_N and update READY here
876 				__set_agg_ports_ready(port->aggregator, __agg_ports_are_ready(port->aggregator));
877 				port->sm_mux_state = AD_MUX_DETACHED;	 // next state
878 				break;
879 			}
880 
881 			// check if the wait_while_timer expired
882 			if (port->sm_mux_timer_counter
883 			    && !(--port->sm_mux_timer_counter))
884 				port->sm_vars |= AD_PORT_READY_N;
885 
886 			// in order to withhold the selection logic to check all ports READY_N value
887 			// every callback cycle to update ready variable, we check READY_N and update READY here
888 			__set_agg_ports_ready(port->aggregator, __agg_ports_are_ready(port->aggregator));
889 
890 			// if the wait_while_timer expired, and the port is in READY state, move to ATTACHED state
891 			if ((port->sm_vars & AD_PORT_READY)
892 			    && !port->sm_mux_timer_counter)
893 				port->sm_mux_state = AD_MUX_ATTACHED;	 // next state
894 			break;
895 		case AD_MUX_ATTACHED:
896 			// check also if agg_select_timer expired(so the edable port will take place only after this timer)
897 			if ((port->sm_vars & AD_PORT_SELECTED) && (port->partner_oper.port_state & AD_STATE_SYNCHRONIZATION) && !__check_agg_selection_timer(port)) {
898 				port->sm_mux_state = AD_MUX_COLLECTING_DISTRIBUTING;// next state
899 			} else if (!(port->sm_vars & AD_PORT_SELECTED) || (port->sm_vars & AD_PORT_STANDBY)) {	  // if UNSELECTED or STANDBY
900 				port->sm_vars &= ~AD_PORT_READY_N;
901 				// in order to withhold the selection logic to check all ports READY_N value
902 				// every callback cycle to update ready variable, we check READY_N and update READY here
903 				__set_agg_ports_ready(port->aggregator, __agg_ports_are_ready(port->aggregator));
904 				port->sm_mux_state = AD_MUX_DETACHED;// next state
905 			}
906 			break;
907 		case AD_MUX_COLLECTING_DISTRIBUTING:
908 			if (!(port->sm_vars & AD_PORT_SELECTED) || (port->sm_vars & AD_PORT_STANDBY) ||
909 			    !(port->partner_oper.port_state & AD_STATE_SYNCHRONIZATION)
910 			   ) {
911 				port->sm_mux_state = AD_MUX_ATTACHED;// next state
912 
913 			} else {
914 				// if port state hasn't changed make
915 				// sure that a collecting distributing
916 				// port in an active aggregator is enabled
917 				if (port->aggregator &&
918 				    port->aggregator->is_active &&
919 				    !__port_is_enabled(port)) {
920 
921 					__enable_port(port);
922 				}
923 			}
924 			break;
925 		default:    //to silence the compiler
926 			break;
927 		}
928 	}
929 
930 	// check if the state machine was changed
931 	if (port->sm_mux_state != last_state) {
932 		pr_debug("Mux Machine: Port=%d, Last State=%d, Curr State=%d\n",
933 			 port->actor_port_number, last_state,
934 			 port->sm_mux_state);
935 		switch (port->sm_mux_state) {
936 		case AD_MUX_DETACHED:
937 			__detach_bond_from_agg(port);
938 			port->actor_oper_port_state &= ~AD_STATE_SYNCHRONIZATION;
939 			ad_disable_collecting_distributing(port);
940 			port->actor_oper_port_state &= ~AD_STATE_COLLECTING;
941 			port->actor_oper_port_state &= ~AD_STATE_DISTRIBUTING;
942 			port->ntt = true;
943 			break;
944 		case AD_MUX_WAITING:
945 			port->sm_mux_timer_counter = __ad_timer_to_ticks(AD_WAIT_WHILE_TIMER, 0);
946 			break;
947 		case AD_MUX_ATTACHED:
948 			__attach_bond_to_agg(port);
949 			port->actor_oper_port_state |= AD_STATE_SYNCHRONIZATION;
950 			port->actor_oper_port_state &= ~AD_STATE_COLLECTING;
951 			port->actor_oper_port_state &= ~AD_STATE_DISTRIBUTING;
952 			ad_disable_collecting_distributing(port);
953 			port->ntt = true;
954 			break;
955 		case AD_MUX_COLLECTING_DISTRIBUTING:
956 			port->actor_oper_port_state |= AD_STATE_COLLECTING;
957 			port->actor_oper_port_state |= AD_STATE_DISTRIBUTING;
958 			ad_enable_collecting_distributing(port);
959 			port->ntt = true;
960 			break;
961 		default:    //to silence the compiler
962 			break;
963 		}
964 	}
965 }
966 
967 /**
968  * ad_rx_machine - handle a port's rx State Machine
969  * @lacpdu: the lacpdu we've received
970  * @port: the port we're looking at
971  *
972  * If lacpdu arrived, stop previous timer (if exists) and set the next state as
973  * CURRENT. If timer expired set the state machine in the proper state.
974  * In other cases, this function checks if we need to switch to other state.
975  */
976 static void ad_rx_machine(struct lacpdu *lacpdu, struct port *port)
977 {
978 	rx_states_t last_state;
979 
980 	// keep current State Machine state to compare later if it was changed
981 	last_state = port->sm_rx_state;
982 
983 	// check if state machine should change state
984 	// first, check if port was reinitialized
985 	if (port->sm_vars & AD_PORT_BEGIN)
986 		/* next state */
987 		port->sm_rx_state = AD_RX_INITIALIZE;
988 	// check if port is not enabled
989 	else if (!(port->sm_vars & AD_PORT_BEGIN)
990 		 && !port->is_enabled && !(port->sm_vars & AD_PORT_MOVED))
991 		/* next state */
992 		port->sm_rx_state = AD_RX_PORT_DISABLED;
993 	// check if new lacpdu arrived
994 	else if (lacpdu && ((port->sm_rx_state == AD_RX_EXPIRED) || (port->sm_rx_state == AD_RX_DEFAULTED) || (port->sm_rx_state == AD_RX_CURRENT))) {
995 		port->sm_rx_timer_counter = 0; // zero timer
996 		port->sm_rx_state = AD_RX_CURRENT;
997 	} else {
998 		// if timer is on, and if it is expired
999 		if (port->sm_rx_timer_counter && !(--port->sm_rx_timer_counter)) {
1000 			switch (port->sm_rx_state) {
1001 			case AD_RX_EXPIRED:
1002 				port->sm_rx_state = AD_RX_DEFAULTED;		// next state
1003 				break;
1004 			case AD_RX_CURRENT:
1005 				port->sm_rx_state = AD_RX_EXPIRED;	    // next state
1006 				break;
1007 			default:    //to silence the compiler
1008 				break;
1009 			}
1010 		} else {
1011 			// if no lacpdu arrived and no timer is on
1012 			switch (port->sm_rx_state) {
1013 			case AD_RX_PORT_DISABLED:
1014 				if (port->sm_vars & AD_PORT_MOVED)
1015 					port->sm_rx_state = AD_RX_INITIALIZE;	    // next state
1016 				else if (port->is_enabled
1017 					 && (port->sm_vars
1018 					     & AD_PORT_LACP_ENABLED))
1019 					port->sm_rx_state = AD_RX_EXPIRED;	// next state
1020 				else if (port->is_enabled
1021 					 && ((port->sm_vars
1022 					      & AD_PORT_LACP_ENABLED) == 0))
1023 					port->sm_rx_state = AD_RX_LACP_DISABLED;    // next state
1024 				break;
1025 			default:    //to silence the compiler
1026 				break;
1027 
1028 			}
1029 		}
1030 	}
1031 
1032 	// check if the State machine was changed or new lacpdu arrived
1033 	if ((port->sm_rx_state != last_state) || (lacpdu)) {
1034 		pr_debug("Rx Machine: Port=%d, Last State=%d, Curr State=%d\n",
1035 			 port->actor_port_number, last_state,
1036 			 port->sm_rx_state);
1037 		switch (port->sm_rx_state) {
1038 		case AD_RX_INITIALIZE:
1039 			if (!(port->actor_oper_port_key & AD_DUPLEX_KEY_BITS))
1040 				port->sm_vars &= ~AD_PORT_LACP_ENABLED;
1041 			else
1042 				port->sm_vars |= AD_PORT_LACP_ENABLED;
1043 			port->sm_vars &= ~AD_PORT_SELECTED;
1044 			__record_default(port);
1045 			port->actor_oper_port_state &= ~AD_STATE_EXPIRED;
1046 			port->sm_vars &= ~AD_PORT_MOVED;
1047 			port->sm_rx_state = AD_RX_PORT_DISABLED;	// next state
1048 
1049 			/*- Fall Through -*/
1050 
1051 		case AD_RX_PORT_DISABLED:
1052 			port->sm_vars &= ~AD_PORT_MATCHED;
1053 			break;
1054 		case AD_RX_LACP_DISABLED:
1055 			port->sm_vars &= ~AD_PORT_SELECTED;
1056 			__record_default(port);
1057 			port->partner_oper.port_state &= ~AD_STATE_AGGREGATION;
1058 			port->sm_vars |= AD_PORT_MATCHED;
1059 			port->actor_oper_port_state &= ~AD_STATE_EXPIRED;
1060 			break;
1061 		case AD_RX_EXPIRED:
1062 			//Reset of the Synchronization flag. (Standard 43.4.12)
1063 			//This reset cause to disable this port in the COLLECTING_DISTRIBUTING state of the
1064 			//mux machine in case of EXPIRED even if LINK_DOWN didn't arrive for the port.
1065 			port->partner_oper.port_state &= ~AD_STATE_SYNCHRONIZATION;
1066 			port->sm_vars &= ~AD_PORT_MATCHED;
1067 			port->partner_oper.port_state |=
1068 				AD_STATE_LACP_ACTIVITY;
1069 			port->sm_rx_timer_counter = __ad_timer_to_ticks(AD_CURRENT_WHILE_TIMER, (u16)(AD_SHORT_TIMEOUT));
1070 			port->actor_oper_port_state |= AD_STATE_EXPIRED;
1071 			break;
1072 		case AD_RX_DEFAULTED:
1073 			__update_default_selected(port);
1074 			__record_default(port);
1075 			port->sm_vars |= AD_PORT_MATCHED;
1076 			port->actor_oper_port_state &= ~AD_STATE_EXPIRED;
1077 			break;
1078 		case AD_RX_CURRENT:
1079 			// detect loopback situation
1080 			if (!MAC_ADDRESS_COMPARE(&(lacpdu->actor_system), &(port->actor_system))) {
1081 				// INFO_RECEIVED_LOOPBACK_FRAMES
1082 				pr_err("%s: An illegal loopback occurred on adapter (%s).\n"
1083 				       "Check the configuration to verify that all adapters are connected to 802.3ad compliant switch ports\n",
1084 				       port->slave->bond->dev->name, port->slave->dev->name);
1085 				return;
1086 			}
1087 			__update_selected(lacpdu, port);
1088 			__update_ntt(lacpdu, port);
1089 			__record_pdu(lacpdu, port);
1090 			port->sm_rx_timer_counter = __ad_timer_to_ticks(AD_CURRENT_WHILE_TIMER, (u16)(port->actor_oper_port_state & AD_STATE_LACP_TIMEOUT));
1091 			port->actor_oper_port_state &= ~AD_STATE_EXPIRED;
1092 			break;
1093 		default:    //to silence the compiler
1094 			break;
1095 		}
1096 	}
1097 }
1098 
1099 /**
1100  * ad_tx_machine - handle a port's tx state machine
1101  * @port: the port we're looking at
1102  *
1103  */
1104 static void ad_tx_machine(struct port *port)
1105 {
1106 	// check if tx timer expired, to verify that we do not send more than 3 packets per second
1107 	if (port->sm_tx_timer_counter && !(--port->sm_tx_timer_counter)) {
1108 		// check if there is something to send
1109 		if (port->ntt && (port->sm_vars & AD_PORT_LACP_ENABLED)) {
1110 			__update_lacpdu_from_port(port);
1111 
1112 			if (ad_lacpdu_send(port) >= 0) {
1113 				pr_debug("Sent LACPDU on port %d\n",
1114 					 port->actor_port_number);
1115 
1116 				/* mark ntt as false, so it will not be sent again until
1117 				   demanded */
1118 				port->ntt = false;
1119 			}
1120 		}
1121 		// restart tx timer(to verify that we will not exceed AD_MAX_TX_IN_SECOND
1122 		port->sm_tx_timer_counter =
1123 			ad_ticks_per_sec/AD_MAX_TX_IN_SECOND;
1124 	}
1125 }
1126 
1127 /**
1128  * ad_periodic_machine - handle a port's periodic state machine
1129  * @port: the port we're looking at
1130  *
1131  * Turn ntt flag on priodically to perform periodic transmission of lacpdu's.
1132  */
1133 static void ad_periodic_machine(struct port *port)
1134 {
1135 	periodic_states_t last_state;
1136 
1137 	// keep current state machine state to compare later if it was changed
1138 	last_state = port->sm_periodic_state;
1139 
1140 	// check if port was reinitialized
1141 	if (((port->sm_vars & AD_PORT_BEGIN) || !(port->sm_vars & AD_PORT_LACP_ENABLED) || !port->is_enabled) ||
1142 	    (!(port->actor_oper_port_state & AD_STATE_LACP_ACTIVITY) && !(port->partner_oper.port_state & AD_STATE_LACP_ACTIVITY))
1143 	   ) {
1144 		port->sm_periodic_state = AD_NO_PERIODIC;	     // next state
1145 	}
1146 	// check if state machine should change state
1147 	else if (port->sm_periodic_timer_counter) {
1148 		// check if periodic state machine expired
1149 		if (!(--port->sm_periodic_timer_counter)) {
1150 			// if expired then do tx
1151 			port->sm_periodic_state = AD_PERIODIC_TX;    // next state
1152 		} else {
1153 			// If not expired, check if there is some new timeout parameter from the partner state
1154 			switch (port->sm_periodic_state) {
1155 			case AD_FAST_PERIODIC:
1156 				if (!(port->partner_oper.port_state
1157 				      & AD_STATE_LACP_TIMEOUT))
1158 					port->sm_periodic_state = AD_SLOW_PERIODIC;  // next state
1159 				break;
1160 			case AD_SLOW_PERIODIC:
1161 				if ((port->partner_oper.port_state & AD_STATE_LACP_TIMEOUT)) {
1162 					// stop current timer
1163 					port->sm_periodic_timer_counter = 0;
1164 					port->sm_periodic_state = AD_PERIODIC_TX;	 // next state
1165 				}
1166 				break;
1167 			default:    //to silence the compiler
1168 				break;
1169 			}
1170 		}
1171 	} else {
1172 		switch (port->sm_periodic_state) {
1173 		case AD_NO_PERIODIC:
1174 			port->sm_periodic_state = AD_FAST_PERIODIC;	 // next state
1175 			break;
1176 		case AD_PERIODIC_TX:
1177 			if (!(port->partner_oper.port_state
1178 			      & AD_STATE_LACP_TIMEOUT))
1179 				port->sm_periodic_state = AD_SLOW_PERIODIC;  // next state
1180 			else
1181 				port->sm_periodic_state = AD_FAST_PERIODIC;  // next state
1182 			break;
1183 		default:    //to silence the compiler
1184 			break;
1185 		}
1186 	}
1187 
1188 	// check if the state machine was changed
1189 	if (port->sm_periodic_state != last_state) {
1190 		pr_debug("Periodic Machine: Port=%d, Last State=%d, Curr State=%d\n",
1191 			 port->actor_port_number, last_state,
1192 			 port->sm_periodic_state);
1193 		switch (port->sm_periodic_state) {
1194 		case AD_NO_PERIODIC:
1195 			port->sm_periodic_timer_counter = 0;	   // zero timer
1196 			break;
1197 		case AD_FAST_PERIODIC:
1198 			port->sm_periodic_timer_counter = __ad_timer_to_ticks(AD_PERIODIC_TIMER, (u16)(AD_FAST_PERIODIC_TIME))-1; // decrement 1 tick we lost in the PERIODIC_TX cycle
1199 			break;
1200 		case AD_SLOW_PERIODIC:
1201 			port->sm_periodic_timer_counter = __ad_timer_to_ticks(AD_PERIODIC_TIMER, (u16)(AD_SLOW_PERIODIC_TIME))-1; // decrement 1 tick we lost in the PERIODIC_TX cycle
1202 			break;
1203 		case AD_PERIODIC_TX:
1204 			port->ntt = true;
1205 			break;
1206 		default:    //to silence the compiler
1207 			break;
1208 		}
1209 	}
1210 }
1211 
1212 /**
1213  * ad_port_selection_logic - select aggregation groups
1214  * @port: the port we're looking at
1215  *
1216  * Select aggregation groups, and assign each port for it's aggregetor. The
1217  * selection logic is called in the inititalization (after all the handshkes),
1218  * and after every lacpdu receive (if selected is off).
1219  */
1220 static void ad_port_selection_logic(struct port *port)
1221 {
1222 	struct aggregator *aggregator, *free_aggregator = NULL, *temp_aggregator;
1223 	struct port *last_port = NULL, *curr_port;
1224 	struct list_head *iter;
1225 	struct bonding *bond;
1226 	struct slave *slave;
1227 	int found = 0;
1228 
1229 	// if the port is already Selected, do nothing
1230 	if (port->sm_vars & AD_PORT_SELECTED)
1231 		return;
1232 
1233 	bond = __get_bond_by_port(port);
1234 
1235 	// if the port is connected to other aggregator, detach it
1236 	if (port->aggregator) {
1237 		// detach the port from its former aggregator
1238 		temp_aggregator = port->aggregator;
1239 		for (curr_port = temp_aggregator->lag_ports; curr_port;
1240 		     last_port = curr_port,
1241 			     curr_port = curr_port->next_port_in_aggregator) {
1242 			if (curr_port == port) {
1243 				temp_aggregator->num_of_ports--;
1244 				if (!last_port) {// if it is the first port attached to the aggregator
1245 					temp_aggregator->lag_ports =
1246 						port->next_port_in_aggregator;
1247 				} else {// not the first port attached to the aggregator
1248 					last_port->next_port_in_aggregator =
1249 						port->next_port_in_aggregator;
1250 				}
1251 
1252 				// clear the port's relations to this aggregator
1253 				port->aggregator = NULL;
1254 				port->next_port_in_aggregator = NULL;
1255 				port->actor_port_aggregator_identifier = 0;
1256 
1257 				pr_debug("Port %d left LAG %d\n",
1258 					 port->actor_port_number,
1259 					 temp_aggregator->aggregator_identifier);
1260 				// if the aggregator is empty, clear its parameters, and set it ready to be attached
1261 				if (!temp_aggregator->lag_ports)
1262 					ad_clear_agg(temp_aggregator);
1263 				break;
1264 			}
1265 		}
1266 		if (!curr_port) { // meaning: the port was related to an aggregator but was not on the aggregator port list
1267 			pr_warning("%s: Warning: Port %d (on %s) was related to aggregator %d but was not on its port list\n",
1268 				   port->slave->bond->dev->name,
1269 				   port->actor_port_number,
1270 				   port->slave->dev->name,
1271 				   port->aggregator->aggregator_identifier);
1272 		}
1273 	}
1274 	// search on all aggregators for a suitable aggregator for this port
1275 	bond_for_each_slave(bond, slave, iter) {
1276 		aggregator = &(SLAVE_AD_INFO(slave).aggregator);
1277 
1278 		// keep a free aggregator for later use(if needed)
1279 		if (!aggregator->lag_ports) {
1280 			if (!free_aggregator)
1281 				free_aggregator = aggregator;
1282 			continue;
1283 		}
1284 		// check if current aggregator suits us
1285 		if (((aggregator->actor_oper_aggregator_key == port->actor_oper_port_key) && // if all parameters match AND
1286 		     !MAC_ADDRESS_COMPARE(&(aggregator->partner_system), &(port->partner_oper.system)) &&
1287 		     (aggregator->partner_system_priority == port->partner_oper.system_priority) &&
1288 		     (aggregator->partner_oper_aggregator_key == port->partner_oper.key)
1289 		    ) &&
1290 		    ((MAC_ADDRESS_COMPARE(&(port->partner_oper.system), &(null_mac_addr)) && // partner answers
1291 		      !aggregator->is_individual)  // but is not individual OR
1292 		    )
1293 		   ) {
1294 			// attach to the founded aggregator
1295 			port->aggregator = aggregator;
1296 			port->actor_port_aggregator_identifier =
1297 				port->aggregator->aggregator_identifier;
1298 			port->next_port_in_aggregator = aggregator->lag_ports;
1299 			port->aggregator->num_of_ports++;
1300 			aggregator->lag_ports = port;
1301 			pr_debug("Port %d joined LAG %d(existing LAG)\n",
1302 				 port->actor_port_number,
1303 				 port->aggregator->aggregator_identifier);
1304 
1305 			// mark this port as selected
1306 			port->sm_vars |= AD_PORT_SELECTED;
1307 			found = 1;
1308 			break;
1309 		}
1310 	}
1311 
1312 	// the port couldn't find an aggregator - attach it to a new aggregator
1313 	if (!found) {
1314 		if (free_aggregator) {
1315 			// assign port a new aggregator
1316 			port->aggregator = free_aggregator;
1317 			port->actor_port_aggregator_identifier =
1318 				port->aggregator->aggregator_identifier;
1319 
1320 			// update the new aggregator's parameters
1321 			// if port was responsed from the end-user
1322 			if (port->actor_oper_port_key & AD_DUPLEX_KEY_BITS)
1323 				/* if port is full duplex */
1324 				port->aggregator->is_individual = false;
1325 			else
1326 				port->aggregator->is_individual = true;
1327 
1328 			port->aggregator->actor_admin_aggregator_key = port->actor_admin_port_key;
1329 			port->aggregator->actor_oper_aggregator_key = port->actor_oper_port_key;
1330 			port->aggregator->partner_system =
1331 				port->partner_oper.system;
1332 			port->aggregator->partner_system_priority =
1333 				port->partner_oper.system_priority;
1334 			port->aggregator->partner_oper_aggregator_key = port->partner_oper.key;
1335 			port->aggregator->receive_state = 1;
1336 			port->aggregator->transmit_state = 1;
1337 			port->aggregator->lag_ports = port;
1338 			port->aggregator->num_of_ports++;
1339 
1340 			// mark this port as selected
1341 			port->sm_vars |= AD_PORT_SELECTED;
1342 
1343 			pr_debug("Port %d joined LAG %d(new LAG)\n",
1344 				 port->actor_port_number,
1345 				 port->aggregator->aggregator_identifier);
1346 		} else {
1347 			pr_err("%s: Port %d (on %s) did not find a suitable aggregator\n",
1348 			       port->slave->bond->dev->name,
1349 			       port->actor_port_number, port->slave->dev->name);
1350 		}
1351 	}
1352 	// if all aggregator's ports are READY_N == TRUE, set ready=TRUE in all aggregator's ports
1353 	// else set ready=FALSE in all aggregator's ports
1354 	__set_agg_ports_ready(port->aggregator, __agg_ports_are_ready(port->aggregator));
1355 
1356 	aggregator = __get_first_agg(port);
1357 	ad_agg_selection_logic(aggregator);
1358 }
1359 
1360 /*
1361  * Decide if "agg" is a better choice for the new active aggregator that
1362  * the current best, according to the ad_select policy.
1363  */
1364 static struct aggregator *ad_agg_selection_test(struct aggregator *best,
1365 						struct aggregator *curr)
1366 {
1367 	/*
1368 	 * 0. If no best, select current.
1369 	 *
1370 	 * 1. If the current agg is not individual, and the best is
1371 	 *    individual, select current.
1372 	 *
1373 	 * 2. If current agg is individual and the best is not, keep best.
1374 	 *
1375 	 * 3. Therefore, current and best are both individual or both not
1376 	 *    individual, so:
1377 	 *
1378 	 * 3a. If current agg partner replied, and best agg partner did not,
1379 	 *     select current.
1380 	 *
1381 	 * 3b. If current agg partner did not reply and best agg partner
1382 	 *     did reply, keep best.
1383 	 *
1384 	 * 4.  Therefore, current and best both have partner replies or
1385 	 *     both do not, so perform selection policy:
1386 	 *
1387 	 * BOND_AD_COUNT: Select by count of ports.  If count is equal,
1388 	 *     select by bandwidth.
1389 	 *
1390 	 * BOND_AD_STABLE, BOND_AD_BANDWIDTH: Select by bandwidth.
1391 	 */
1392 	if (!best)
1393 		return curr;
1394 
1395 	if (!curr->is_individual && best->is_individual)
1396 		return curr;
1397 
1398 	if (curr->is_individual && !best->is_individual)
1399 		return best;
1400 
1401 	if (__agg_has_partner(curr) && !__agg_has_partner(best))
1402 		return curr;
1403 
1404 	if (!__agg_has_partner(curr) && __agg_has_partner(best))
1405 		return best;
1406 
1407 	switch (__get_agg_selection_mode(curr->lag_ports)) {
1408 	case BOND_AD_COUNT:
1409 		if (curr->num_of_ports > best->num_of_ports)
1410 			return curr;
1411 
1412 		if (curr->num_of_ports < best->num_of_ports)
1413 			return best;
1414 
1415 		/*FALLTHROUGH*/
1416 	case BOND_AD_STABLE:
1417 	case BOND_AD_BANDWIDTH:
1418 		if (__get_agg_bandwidth(curr) > __get_agg_bandwidth(best))
1419 			return curr;
1420 
1421 		break;
1422 
1423 	default:
1424 		pr_warning("%s: Impossible agg select mode %d\n",
1425 			   curr->slave->bond->dev->name,
1426 			   __get_agg_selection_mode(curr->lag_ports));
1427 		break;
1428 	}
1429 
1430 	return best;
1431 }
1432 
1433 static int agg_device_up(const struct aggregator *agg)
1434 {
1435 	struct port *port = agg->lag_ports;
1436 	if (!port)
1437 		return 0;
1438 	return (netif_running(port->slave->dev) &&
1439 		netif_carrier_ok(port->slave->dev));
1440 }
1441 
1442 /**
1443  * ad_agg_selection_logic - select an aggregation group for a team
1444  * @aggregator: the aggregator we're looking at
1445  *
1446  * It is assumed that only one aggregator may be selected for a team.
1447  *
1448  * The logic of this function is to select the aggregator according to
1449  * the ad_select policy:
1450  *
1451  * BOND_AD_STABLE: select the aggregator with the most ports attached to
1452  * it, and to reselect the active aggregator only if the previous
1453  * aggregator has no more ports related to it.
1454  *
1455  * BOND_AD_BANDWIDTH: select the aggregator with the highest total
1456  * bandwidth, and reselect whenever a link state change takes place or the
1457  * set of slaves in the bond changes.
1458  *
1459  * BOND_AD_COUNT: select the aggregator with largest number of ports
1460  * (slaves), and reselect whenever a link state change takes place or the
1461  * set of slaves in the bond changes.
1462  *
1463  * FIXME: this function MUST be called with the first agg in the bond, or
1464  * __get_active_agg() won't work correctly. This function should be better
1465  * called with the bond itself, and retrieve the first agg from it.
1466  */
1467 static void ad_agg_selection_logic(struct aggregator *agg)
1468 {
1469 	struct aggregator *best, *active, *origin;
1470 	struct bonding *bond = agg->slave->bond;
1471 	struct list_head *iter;
1472 	struct slave *slave;
1473 	struct port *port;
1474 
1475 	origin = agg;
1476 	active = __get_active_agg(agg);
1477 	best = (active && agg_device_up(active)) ? active : NULL;
1478 
1479 	rcu_read_lock();
1480 	bond_for_each_slave_rcu(bond, slave, iter) {
1481 		agg = &(SLAVE_AD_INFO(slave).aggregator);
1482 
1483 		agg->is_active = 0;
1484 
1485 		if (agg->num_of_ports && agg_device_up(agg))
1486 			best = ad_agg_selection_test(best, agg);
1487 	}
1488 
1489 	if (best &&
1490 	    __get_agg_selection_mode(best->lag_ports) == BOND_AD_STABLE) {
1491 		/*
1492 		 * For the STABLE policy, don't replace the old active
1493 		 * aggregator if it's still active (it has an answering
1494 		 * partner) or if both the best and active don't have an
1495 		 * answering partner.
1496 		 */
1497 		if (active && active->lag_ports &&
1498 		    active->lag_ports->is_enabled &&
1499 		    (__agg_has_partner(active) ||
1500 		     (!__agg_has_partner(active) && !__agg_has_partner(best)))) {
1501 			if (!(!active->actor_oper_aggregator_key &&
1502 			      best->actor_oper_aggregator_key)) {
1503 				best = NULL;
1504 				active->is_active = 1;
1505 			}
1506 		}
1507 	}
1508 
1509 	if (best && (best == active)) {
1510 		best = NULL;
1511 		active->is_active = 1;
1512 	}
1513 
1514 	/* if there is new best aggregator, activate it */
1515 	if (best) {
1516 		pr_debug("best Agg=%d; P=%d; a k=%d; p k=%d; Ind=%d; Act=%d\n",
1517 			 best->aggregator_identifier, best->num_of_ports,
1518 			 best->actor_oper_aggregator_key,
1519 			 best->partner_oper_aggregator_key,
1520 			 best->is_individual, best->is_active);
1521 		pr_debug("best ports %p slave %p %s\n",
1522 			 best->lag_ports, best->slave,
1523 			 best->slave ? best->slave->dev->name : "NULL");
1524 
1525 		bond_for_each_slave_rcu(bond, slave, iter) {
1526 			agg = &(SLAVE_AD_INFO(slave).aggregator);
1527 
1528 			pr_debug("Agg=%d; P=%d; a k=%d; p k=%d; Ind=%d; Act=%d\n",
1529 				 agg->aggregator_identifier, agg->num_of_ports,
1530 				 agg->actor_oper_aggregator_key,
1531 				 agg->partner_oper_aggregator_key,
1532 				 agg->is_individual, agg->is_active);
1533 		}
1534 
1535 		/* check if any partner replys */
1536 		if (best->is_individual) {
1537 			pr_warning("%s: Warning: No 802.3ad response from the link partner for any adapters in the bond\n",
1538 				best->slave ?
1539 				best->slave->bond->dev->name : "NULL");
1540 		}
1541 
1542 		best->is_active = 1;
1543 		pr_debug("LAG %d chosen as the active LAG\n",
1544 			 best->aggregator_identifier);
1545 		pr_debug("Agg=%d; P=%d; a k=%d; p k=%d; Ind=%d; Act=%d\n",
1546 			 best->aggregator_identifier, best->num_of_ports,
1547 			 best->actor_oper_aggregator_key,
1548 			 best->partner_oper_aggregator_key,
1549 			 best->is_individual, best->is_active);
1550 
1551 		/* disable the ports that were related to the former active_aggregator */
1552 		if (active) {
1553 			for (port = active->lag_ports; port;
1554 			     port = port->next_port_in_aggregator) {
1555 				__disable_port(port);
1556 			}
1557 		}
1558 	}
1559 
1560 	/*
1561 	 * if the selected aggregator is of join individuals
1562 	 * (partner_system is NULL), enable their ports
1563 	 */
1564 	active = __get_active_agg(origin);
1565 
1566 	if (active) {
1567 		if (!__agg_has_partner(active)) {
1568 			for (port = active->lag_ports; port;
1569 			     port = port->next_port_in_aggregator) {
1570 				__enable_port(port);
1571 			}
1572 		}
1573 	}
1574 
1575 	rcu_read_unlock();
1576 
1577 	bond_3ad_set_carrier(bond);
1578 }
1579 
1580 /**
1581  * ad_clear_agg - clear a given aggregator's parameters
1582  * @aggregator: the aggregator we're looking at
1583  *
1584  */
1585 static void ad_clear_agg(struct aggregator *aggregator)
1586 {
1587 	if (aggregator) {
1588 		aggregator->is_individual = false;
1589 		aggregator->actor_admin_aggregator_key = 0;
1590 		aggregator->actor_oper_aggregator_key = 0;
1591 		aggregator->partner_system = null_mac_addr;
1592 		aggregator->partner_system_priority = 0;
1593 		aggregator->partner_oper_aggregator_key = 0;
1594 		aggregator->receive_state = 0;
1595 		aggregator->transmit_state = 0;
1596 		aggregator->lag_ports = NULL;
1597 		aggregator->is_active = 0;
1598 		aggregator->num_of_ports = 0;
1599 		pr_debug("LAG %d was cleared\n",
1600 			 aggregator->aggregator_identifier);
1601 	}
1602 }
1603 
1604 /**
1605  * ad_initialize_agg - initialize a given aggregator's parameters
1606  * @aggregator: the aggregator we're looking at
1607  *
1608  */
1609 static void ad_initialize_agg(struct aggregator *aggregator)
1610 {
1611 	if (aggregator) {
1612 		ad_clear_agg(aggregator);
1613 
1614 		aggregator->aggregator_mac_address = null_mac_addr;
1615 		aggregator->aggregator_identifier = 0;
1616 		aggregator->slave = NULL;
1617 	}
1618 }
1619 
1620 /**
1621  * ad_initialize_port - initialize a given port's parameters
1622  * @aggregator: the aggregator we're looking at
1623  * @lacp_fast: boolean. whether fast periodic should be used
1624  *
1625  */
1626 static void ad_initialize_port(struct port *port, int lacp_fast)
1627 {
1628 	static const struct port_params tmpl = {
1629 		.system_priority = 0xffff,
1630 		.key             = 1,
1631 		.port_number     = 1,
1632 		.port_priority   = 0xff,
1633 		.port_state      = 1,
1634 	};
1635 	static const struct lacpdu lacpdu = {
1636 		.subtype		= 0x01,
1637 		.version_number = 0x01,
1638 		.tlv_type_actor_info = 0x01,
1639 		.actor_information_length = 0x14,
1640 		.tlv_type_partner_info = 0x02,
1641 		.partner_information_length = 0x14,
1642 		.tlv_type_collector_info = 0x03,
1643 		.collector_information_length = 0x10,
1644 		.collector_max_delay = htons(AD_COLLECTOR_MAX_DELAY),
1645 	};
1646 
1647 	if (port) {
1648 		port->actor_port_number = 1;
1649 		port->actor_port_priority = 0xff;
1650 		port->actor_system = null_mac_addr;
1651 		port->actor_system_priority = 0xffff;
1652 		port->actor_port_aggregator_identifier = 0;
1653 		port->ntt = false;
1654 		port->actor_admin_port_key = 1;
1655 		port->actor_oper_port_key  = 1;
1656 		port->actor_admin_port_state = AD_STATE_AGGREGATION | AD_STATE_LACP_ACTIVITY;
1657 		port->actor_oper_port_state  = AD_STATE_AGGREGATION | AD_STATE_LACP_ACTIVITY;
1658 
1659 		if (lacp_fast)
1660 			port->actor_oper_port_state |= AD_STATE_LACP_TIMEOUT;
1661 
1662 		memcpy(&port->partner_admin, &tmpl, sizeof(tmpl));
1663 		memcpy(&port->partner_oper, &tmpl, sizeof(tmpl));
1664 
1665 		port->is_enabled = true;
1666 		// ****** private parameters ******
1667 		port->sm_vars = 0x3;
1668 		port->sm_rx_state = 0;
1669 		port->sm_rx_timer_counter = 0;
1670 		port->sm_periodic_state = 0;
1671 		port->sm_periodic_timer_counter = 0;
1672 		port->sm_mux_state = 0;
1673 		port->sm_mux_timer_counter = 0;
1674 		port->sm_tx_state = 0;
1675 		port->sm_tx_timer_counter = 0;
1676 		port->slave = NULL;
1677 		port->aggregator = NULL;
1678 		port->next_port_in_aggregator = NULL;
1679 		port->transaction_id = 0;
1680 
1681 		memcpy(&port->lacpdu, &lacpdu, sizeof(lacpdu));
1682 	}
1683 }
1684 
1685 /**
1686  * ad_enable_collecting_distributing - enable a port's transmit/receive
1687  * @port: the port we're looking at
1688  *
1689  * Enable @port if it's in an active aggregator
1690  */
1691 static void ad_enable_collecting_distributing(struct port *port)
1692 {
1693 	if (port->aggregator->is_active) {
1694 		pr_debug("Enabling port %d(LAG %d)\n",
1695 			 port->actor_port_number,
1696 			 port->aggregator->aggregator_identifier);
1697 		__enable_port(port);
1698 	}
1699 }
1700 
1701 /**
1702  * ad_disable_collecting_distributing - disable a port's transmit/receive
1703  * @port: the port we're looking at
1704  *
1705  */
1706 static void ad_disable_collecting_distributing(struct port *port)
1707 {
1708 	if (port->aggregator && MAC_ADDRESS_COMPARE(&(port->aggregator->partner_system), &(null_mac_addr))) {
1709 		pr_debug("Disabling port %d(LAG %d)\n",
1710 			 port->actor_port_number,
1711 			 port->aggregator->aggregator_identifier);
1712 		__disable_port(port);
1713 	}
1714 }
1715 
1716 #if 0
1717 /**
1718  * ad_marker_info_send - send a marker information frame
1719  * @port: the port we're looking at
1720  *
1721  * This function does nothing since we decided not to implement send and handle
1722  * response for marker PDU's, in this stage, but only to respond to marker
1723  * information.
1724  */
1725 static void ad_marker_info_send(struct port *port)
1726 {
1727 	struct bond_marker marker;
1728 	u16 index;
1729 
1730 	// fill the marker PDU with the appropriate values
1731 	marker.subtype = 0x02;
1732 	marker.version_number = 0x01;
1733 	marker.tlv_type = AD_MARKER_INFORMATION_SUBTYPE;
1734 	marker.marker_length = 0x16;
1735 	// convert requester_port to Big Endian
1736 	marker.requester_port = (((port->actor_port_number & 0xFF) << 8) |((u16)(port->actor_port_number & 0xFF00) >> 8));
1737 	marker.requester_system = port->actor_system;
1738 	// convert requester_port(u32) to Big Endian
1739 	marker.requester_transaction_id =
1740 		(((++port->transaction_id & 0xFF) << 24)
1741 		 | ((port->transaction_id & 0xFF00) << 8)
1742 		 | ((port->transaction_id & 0xFF0000) >> 8)
1743 		 | ((port->transaction_id & 0xFF000000) >> 24));
1744 	marker.pad = 0;
1745 	marker.tlv_type_terminator = 0x00;
1746 	marker.terminator_length = 0x00;
1747 	for (index = 0; index < 90; index++)
1748 		marker.reserved_90[index] = 0;
1749 
1750 	// send the marker information
1751 	if (ad_marker_send(port, &marker) >= 0) {
1752 		pr_debug("Sent Marker Information on port %d\n",
1753 			 port->actor_port_number);
1754 	}
1755 }
1756 #endif
1757 
1758 /**
1759  * ad_marker_info_received - handle receive of a Marker information frame
1760  * @marker_info: Marker info received
1761  * @port: the port we're looking at
1762  *
1763  */
1764 static void ad_marker_info_received(struct bond_marker *marker_info,
1765 	struct port *port)
1766 {
1767 	struct bond_marker marker;
1768 
1769 	// copy the received marker data to the response marker
1770 	//marker = *marker_info;
1771 	memcpy(&marker, marker_info, sizeof(struct bond_marker));
1772 	// change the marker subtype to marker response
1773 	marker.tlv_type = AD_MARKER_RESPONSE_SUBTYPE;
1774 	// send the marker response
1775 
1776 	if (ad_marker_send(port, &marker) >= 0) {
1777 		pr_debug("Sent Marker Response on port %d\n",
1778 			 port->actor_port_number);
1779 	}
1780 }
1781 
1782 /**
1783  * ad_marker_response_received - handle receive of a marker response frame
1784  * @marker: marker PDU received
1785  * @port: the port we're looking at
1786  *
1787  * This function does nothing since we decided not to implement send and handle
1788  * response for marker PDU's, in this stage, but only to respond to marker
1789  * information.
1790  */
1791 static void ad_marker_response_received(struct bond_marker *marker,
1792 	struct port *port)
1793 {
1794 	marker = NULL; /* just to satisfy the compiler */
1795 	port = NULL;  /* just to satisfy the compiler */
1796 	// DO NOTHING, SINCE WE DECIDED NOT TO IMPLEMENT THIS FEATURE FOR NOW
1797 }
1798 
1799 //////////////////////////////////////////////////////////////////////////////////////
1800 // ================= AD exported functions to the main bonding code ==================
1801 //////////////////////////////////////////////////////////////////////////////////////
1802 
1803 // Check aggregators status in team every T seconds
1804 #define AD_AGGREGATOR_SELECTION_TIMER  8
1805 
1806 /*
1807  * bond_3ad_initiate_agg_selection(struct bonding *bond)
1808  *
1809  * Set the aggregation selection timer, to initiate an agg selection in
1810  * the very near future.  Called during first initialization, and during
1811  * any down to up transitions of the bond.
1812  */
1813 void bond_3ad_initiate_agg_selection(struct bonding *bond, int timeout)
1814 {
1815 	BOND_AD_INFO(bond).agg_select_timer = timeout;
1816 }
1817 
1818 static u16 aggregator_identifier;
1819 
1820 /**
1821  * bond_3ad_initialize - initialize a bond's 802.3ad parameters and structures
1822  * @bond: bonding struct to work on
1823  * @tick_resolution: tick duration (millisecond resolution)
1824  *
1825  * Can be called only after the mac address of the bond is set.
1826  */
1827 void bond_3ad_initialize(struct bonding *bond, u16 tick_resolution)
1828 {
1829 	// check that the bond is not initialized yet
1830 	if (MAC_ADDRESS_COMPARE(&(BOND_AD_INFO(bond).system.sys_mac_addr),
1831 				bond->dev->dev_addr)) {
1832 
1833 		aggregator_identifier = 0;
1834 
1835 		BOND_AD_INFO(bond).system.sys_priority = 0xFFFF;
1836 		BOND_AD_INFO(bond).system.sys_mac_addr = *((struct mac_addr *)bond->dev->dev_addr);
1837 
1838 		// initialize how many times this module is called in one second(should be about every 100ms)
1839 		ad_ticks_per_sec = tick_resolution;
1840 
1841 		bond_3ad_initiate_agg_selection(bond,
1842 						AD_AGGREGATOR_SELECTION_TIMER *
1843 						ad_ticks_per_sec);
1844 	}
1845 }
1846 
1847 /**
1848  * bond_3ad_bind_slave - initialize a slave's port
1849  * @slave: slave struct to work on
1850  *
1851  * Returns:   0 on success
1852  *          < 0 on error
1853  */
1854 int bond_3ad_bind_slave(struct slave *slave)
1855 {
1856 	struct bonding *bond = bond_get_bond_by_slave(slave);
1857 	struct port *port;
1858 	struct aggregator *aggregator;
1859 
1860 	if (bond == NULL) {
1861 		pr_err("%s: The slave %s is not attached to its bond\n",
1862 		       slave->bond->dev->name, slave->dev->name);
1863 		return -1;
1864 	}
1865 
1866 	//check that the slave has not been initialized yet.
1867 	if (SLAVE_AD_INFO(slave).port.slave != slave) {
1868 
1869 		// port initialization
1870 		port = &(SLAVE_AD_INFO(slave).port);
1871 
1872 		ad_initialize_port(port, bond->params.lacp_fast);
1873 
1874 		__initialize_port_locks(slave);
1875 		port->slave = slave;
1876 		port->actor_port_number = SLAVE_AD_INFO(slave).id;
1877 		// key is determined according to the link speed, duplex and user key(which is yet not supported)
1878 		//              ------------------------------------------------------------
1879 		// Port key :   | User key                       |      Speed       |Duplex|
1880 		//              ------------------------------------------------------------
1881 		//              16                               6               1 0
1882 		port->actor_admin_port_key = 0;	// initialize this parameter
1883 		port->actor_admin_port_key |= __get_duplex(port);
1884 		port->actor_admin_port_key |= (__get_link_speed(port) << 1);
1885 		port->actor_oper_port_key = port->actor_admin_port_key;
1886 		// if the port is not full duplex, then the port should be not lacp Enabled
1887 		if (!(port->actor_oper_port_key & AD_DUPLEX_KEY_BITS))
1888 			port->sm_vars &= ~AD_PORT_LACP_ENABLED;
1889 		// actor system is the bond's system
1890 		port->actor_system = BOND_AD_INFO(bond).system.sys_mac_addr;
1891 		// tx timer(to verify that no more than MAX_TX_IN_SECOND lacpdu's are sent in one second)
1892 		port->sm_tx_timer_counter = ad_ticks_per_sec/AD_MAX_TX_IN_SECOND;
1893 		port->aggregator = NULL;
1894 		port->next_port_in_aggregator = NULL;
1895 
1896 		__disable_port(port);
1897 
1898 		// aggregator initialization
1899 		aggregator = &(SLAVE_AD_INFO(slave).aggregator);
1900 
1901 		ad_initialize_agg(aggregator);
1902 
1903 		aggregator->aggregator_mac_address = *((struct mac_addr *)bond->dev->dev_addr);
1904 		aggregator->aggregator_identifier = (++aggregator_identifier);
1905 		aggregator->slave = slave;
1906 		aggregator->is_active = 0;
1907 		aggregator->num_of_ports = 0;
1908 	}
1909 
1910 	return 0;
1911 }
1912 
1913 /**
1914  * bond_3ad_unbind_slave - deinitialize a slave's port
1915  * @slave: slave struct to work on
1916  *
1917  * Search for the aggregator that is related to this port, remove the
1918  * aggregator and assign another aggregator for other port related to it
1919  * (if any), and remove the port.
1920  */
1921 void bond_3ad_unbind_slave(struct slave *slave)
1922 {
1923 	struct port *port, *prev_port, *temp_port;
1924 	struct aggregator *aggregator, *new_aggregator, *temp_aggregator;
1925 	int select_new_active_agg = 0;
1926 	struct bonding *bond = slave->bond;
1927 	struct slave *slave_iter;
1928 	struct list_head *iter;
1929 
1930 	// find the aggregator related to this slave
1931 	aggregator = &(SLAVE_AD_INFO(slave).aggregator);
1932 
1933 	// find the port related to this slave
1934 	port = &(SLAVE_AD_INFO(slave).port);
1935 
1936 	// if slave is null, the whole port is not initialized
1937 	if (!port->slave) {
1938 		pr_warning("Warning: %s: Trying to unbind an uninitialized port on %s\n",
1939 			   slave->bond->dev->name, slave->dev->name);
1940 		return;
1941 	}
1942 
1943 	pr_debug("Unbinding Link Aggregation Group %d\n",
1944 		 aggregator->aggregator_identifier);
1945 
1946 	/* Tell the partner that this port is not suitable for aggregation */
1947 	port->actor_oper_port_state &= ~AD_STATE_AGGREGATION;
1948 	__update_lacpdu_from_port(port);
1949 	ad_lacpdu_send(port);
1950 
1951 	// check if this aggregator is occupied
1952 	if (aggregator->lag_ports) {
1953 		// check if there are other ports related to this aggregator except
1954 		// the port related to this slave(thats ensure us that there is a
1955 		// reason to search for new aggregator, and that we will find one
1956 		if ((aggregator->lag_ports != port) || (aggregator->lag_ports->next_port_in_aggregator)) {
1957 			// find new aggregator for the related port(s)
1958 			bond_for_each_slave(bond, slave_iter, iter) {
1959 				new_aggregator = &(SLAVE_AD_INFO(slave_iter).aggregator);
1960 				// if the new aggregator is empty, or it is connected to our port only
1961 				if (!new_aggregator->lag_ports
1962 				    || ((new_aggregator->lag_ports == port)
1963 					&& !new_aggregator->lag_ports->next_port_in_aggregator))
1964 					break;
1965 			}
1966 			if (!slave_iter)
1967 				new_aggregator = NULL;
1968 			// if new aggregator found, copy the aggregator's parameters
1969 			// and connect the related lag_ports to the new aggregator
1970 			if ((new_aggregator) && ((!new_aggregator->lag_ports) || ((new_aggregator->lag_ports == port) && !new_aggregator->lag_ports->next_port_in_aggregator))) {
1971 				pr_debug("Some port(s) related to LAG %d - replaceing with LAG %d\n",
1972 					 aggregator->aggregator_identifier,
1973 					 new_aggregator->aggregator_identifier);
1974 
1975 				if ((new_aggregator->lag_ports == port) && new_aggregator->is_active) {
1976 					pr_info("%s: Removing an active aggregator\n",
1977 						aggregator->slave->bond->dev->name);
1978 					// select new active aggregator
1979 					 select_new_active_agg = 1;
1980 				}
1981 
1982 				new_aggregator->is_individual = aggregator->is_individual;
1983 				new_aggregator->actor_admin_aggregator_key = aggregator->actor_admin_aggregator_key;
1984 				new_aggregator->actor_oper_aggregator_key = aggregator->actor_oper_aggregator_key;
1985 				new_aggregator->partner_system = aggregator->partner_system;
1986 				new_aggregator->partner_system_priority = aggregator->partner_system_priority;
1987 				new_aggregator->partner_oper_aggregator_key = aggregator->partner_oper_aggregator_key;
1988 				new_aggregator->receive_state = aggregator->receive_state;
1989 				new_aggregator->transmit_state = aggregator->transmit_state;
1990 				new_aggregator->lag_ports = aggregator->lag_ports;
1991 				new_aggregator->is_active = aggregator->is_active;
1992 				new_aggregator->num_of_ports = aggregator->num_of_ports;
1993 
1994 				// update the information that is written on the ports about the aggregator
1995 				for (temp_port = aggregator->lag_ports; temp_port;
1996 				     temp_port = temp_port->next_port_in_aggregator) {
1997 					temp_port->aggregator = new_aggregator;
1998 					temp_port->actor_port_aggregator_identifier = new_aggregator->aggregator_identifier;
1999 				}
2000 
2001 				// clear the aggregator
2002 				ad_clear_agg(aggregator);
2003 
2004 				if (select_new_active_agg)
2005 					ad_agg_selection_logic(__get_first_agg(port));
2006 			} else {
2007 				pr_warning("%s: Warning: unbinding aggregator, and could not find a new aggregator for its ports\n",
2008 					   slave->bond->dev->name);
2009 			}
2010 		} else { // in case that the only port related to this aggregator is the one we want to remove
2011 			select_new_active_agg = aggregator->is_active;
2012 			// clear the aggregator
2013 			ad_clear_agg(aggregator);
2014 			if (select_new_active_agg) {
2015 				pr_info("%s: Removing an active aggregator\n",
2016 					slave->bond->dev->name);
2017 				// select new active aggregator
2018 				temp_aggregator = __get_first_agg(port);
2019 				if (temp_aggregator)
2020 					ad_agg_selection_logic(temp_aggregator);
2021 			}
2022 		}
2023 	}
2024 
2025 	pr_debug("Unbinding port %d\n", port->actor_port_number);
2026 	// find the aggregator that this port is connected to
2027 	bond_for_each_slave(bond, slave_iter, iter) {
2028 		temp_aggregator = &(SLAVE_AD_INFO(slave_iter).aggregator);
2029 		prev_port = NULL;
2030 		// search the port in the aggregator's related ports
2031 		for (temp_port = temp_aggregator->lag_ports; temp_port;
2032 		     prev_port = temp_port,
2033 			     temp_port = temp_port->next_port_in_aggregator) {
2034 			if (temp_port == port) { // the aggregator found - detach the port from this aggregator
2035 				if (prev_port)
2036 					prev_port->next_port_in_aggregator = temp_port->next_port_in_aggregator;
2037 				else
2038 					temp_aggregator->lag_ports = temp_port->next_port_in_aggregator;
2039 				temp_aggregator->num_of_ports--;
2040 				if (temp_aggregator->num_of_ports == 0) {
2041 					select_new_active_agg = temp_aggregator->is_active;
2042 					// clear the aggregator
2043 					ad_clear_agg(temp_aggregator);
2044 					if (select_new_active_agg) {
2045 						pr_info("%s: Removing an active aggregator\n",
2046 							slave->bond->dev->name);
2047 						// select new active aggregator
2048 						ad_agg_selection_logic(__get_first_agg(port));
2049 					}
2050 				}
2051 				break;
2052 			}
2053 		}
2054 	}
2055 	port->slave = NULL;
2056 }
2057 
2058 /**
2059  * bond_3ad_state_machine_handler - handle state machines timeout
2060  * @bond: bonding struct to work on
2061  *
2062  * The state machine handling concept in this module is to check every tick
2063  * which state machine should operate any function. The execution order is
2064  * round robin, so when we have an interaction between state machines, the
2065  * reply of one to each other might be delayed until next tick.
2066  *
2067  * This function also complete the initialization when the agg_select_timer
2068  * times out, and it selects an aggregator for the ports that are yet not
2069  * related to any aggregator, and selects the active aggregator for a bond.
2070  */
2071 void bond_3ad_state_machine_handler(struct work_struct *work)
2072 {
2073 	struct bonding *bond = container_of(work, struct bonding,
2074 					    ad_work.work);
2075 	struct aggregator *aggregator;
2076 	struct list_head *iter;
2077 	struct slave *slave;
2078 	struct port *port;
2079 
2080 	read_lock(&bond->lock);
2081 	rcu_read_lock();
2082 
2083 	/* check if there are any slaves */
2084 	if (!bond_has_slaves(bond))
2085 		goto re_arm;
2086 
2087 	/* check if agg_select_timer timer after initialize is timed out */
2088 	if (BOND_AD_INFO(bond).agg_select_timer && !(--BOND_AD_INFO(bond).agg_select_timer)) {
2089 		slave = bond_first_slave_rcu(bond);
2090 		port = slave ? &(SLAVE_AD_INFO(slave).port) : NULL;
2091 
2092 		/* select the active aggregator for the bond */
2093 		if (port) {
2094 			if (!port->slave) {
2095 				pr_warning("%s: Warning: bond's first port is uninitialized\n",
2096 					   bond->dev->name);
2097 				goto re_arm;
2098 			}
2099 
2100 			aggregator = __get_first_agg(port);
2101 			ad_agg_selection_logic(aggregator);
2102 		}
2103 		bond_3ad_set_carrier(bond);
2104 	}
2105 
2106 	/* for each port run the state machines */
2107 	bond_for_each_slave_rcu(bond, slave, iter) {
2108 		port = &(SLAVE_AD_INFO(slave).port);
2109 		if (!port->slave) {
2110 			pr_warning("%s: Warning: Found an uninitialized port\n",
2111 				   bond->dev->name);
2112 			goto re_arm;
2113 		}
2114 
2115 		/* Lock around state machines to protect data accessed
2116 		 * by all (e.g., port->sm_vars).  ad_rx_machine may run
2117 		 * concurrently due to incoming LACPDU.
2118 		 */
2119 		__get_state_machine_lock(port);
2120 
2121 		ad_rx_machine(NULL, port);
2122 		ad_periodic_machine(port);
2123 		ad_port_selection_logic(port);
2124 		ad_mux_machine(port);
2125 		ad_tx_machine(port);
2126 
2127 		/* turn off the BEGIN bit, since we already handled it */
2128 		if (port->sm_vars & AD_PORT_BEGIN)
2129 			port->sm_vars &= ~AD_PORT_BEGIN;
2130 
2131 		__release_state_machine_lock(port);
2132 	}
2133 
2134 re_arm:
2135 	rcu_read_unlock();
2136 	read_unlock(&bond->lock);
2137 	queue_delayed_work(bond->wq, &bond->ad_work, ad_delta_in_ticks);
2138 }
2139 
2140 /**
2141  * bond_3ad_rx_indication - handle a received frame
2142  * @lacpdu: received lacpdu
2143  * @slave: slave struct to work on
2144  * @length: length of the data received
2145  *
2146  * It is assumed that frames that were sent on this NIC don't returned as new
2147  * received frames (loopback). Since only the payload is given to this
2148  * function, it check for loopback.
2149  */
2150 static int bond_3ad_rx_indication(struct lacpdu *lacpdu, struct slave *slave, u16 length)
2151 {
2152 	struct port *port;
2153 	int ret = RX_HANDLER_ANOTHER;
2154 
2155 	if (length >= sizeof(struct lacpdu)) {
2156 
2157 		port = &(SLAVE_AD_INFO(slave).port);
2158 
2159 		if (!port->slave) {
2160 			pr_warning("%s: Warning: port of slave %s is uninitialized\n",
2161 				   slave->dev->name, slave->bond->dev->name);
2162 			return ret;
2163 		}
2164 
2165 		switch (lacpdu->subtype) {
2166 		case AD_TYPE_LACPDU:
2167 			ret = RX_HANDLER_CONSUMED;
2168 			pr_debug("Received LACPDU on port %d\n",
2169 				 port->actor_port_number);
2170 			/* Protect against concurrent state machines */
2171 			__get_state_machine_lock(port);
2172 			ad_rx_machine(lacpdu, port);
2173 			__release_state_machine_lock(port);
2174 			break;
2175 
2176 		case AD_TYPE_MARKER:
2177 			ret = RX_HANDLER_CONSUMED;
2178 			// No need to convert fields to Little Endian since we don't use the marker's fields.
2179 
2180 			switch (((struct bond_marker *)lacpdu)->tlv_type) {
2181 			case AD_MARKER_INFORMATION_SUBTYPE:
2182 				pr_debug("Received Marker Information on port %d\n",
2183 					 port->actor_port_number);
2184 				ad_marker_info_received((struct bond_marker *)lacpdu, port);
2185 				break;
2186 
2187 			case AD_MARKER_RESPONSE_SUBTYPE:
2188 				pr_debug("Received Marker Response on port %d\n",
2189 					 port->actor_port_number);
2190 				ad_marker_response_received((struct bond_marker *)lacpdu, port);
2191 				break;
2192 
2193 			default:
2194 				pr_debug("Received an unknown Marker subtype on slot %d\n",
2195 					 port->actor_port_number);
2196 			}
2197 		}
2198 	}
2199 	return ret;
2200 }
2201 
2202 /**
2203  * bond_3ad_adapter_speed_changed - handle a slave's speed change indication
2204  * @slave: slave struct to work on
2205  *
2206  * Handle reselection of aggregator (if needed) for this port.
2207  */
2208 void bond_3ad_adapter_speed_changed(struct slave *slave)
2209 {
2210 	struct port *port;
2211 
2212 	port = &(SLAVE_AD_INFO(slave).port);
2213 
2214 	// if slave is null, the whole port is not initialized
2215 	if (!port->slave) {
2216 		pr_warning("Warning: %s: speed changed for uninitialized port on %s\n",
2217 			   slave->bond->dev->name, slave->dev->name);
2218 		return;
2219 	}
2220 
2221 	port->actor_admin_port_key &= ~AD_SPEED_KEY_BITS;
2222 	port->actor_oper_port_key = port->actor_admin_port_key |=
2223 		(__get_link_speed(port) << 1);
2224 	pr_debug("Port %d changed speed\n", port->actor_port_number);
2225 	// there is no need to reselect a new aggregator, just signal the
2226 	// state machines to reinitialize
2227 	port->sm_vars |= AD_PORT_BEGIN;
2228 }
2229 
2230 /**
2231  * bond_3ad_adapter_duplex_changed - handle a slave's duplex change indication
2232  * @slave: slave struct to work on
2233  *
2234  * Handle reselection of aggregator (if needed) for this port.
2235  */
2236 void bond_3ad_adapter_duplex_changed(struct slave *slave)
2237 {
2238 	struct port *port;
2239 
2240 	port = &(SLAVE_AD_INFO(slave).port);
2241 
2242 	// if slave is null, the whole port is not initialized
2243 	if (!port->slave) {
2244 		pr_warning("%s: Warning: duplex changed for uninitialized port on %s\n",
2245 			   slave->bond->dev->name, slave->dev->name);
2246 		return;
2247 	}
2248 
2249 	port->actor_admin_port_key &= ~AD_DUPLEX_KEY_BITS;
2250 	port->actor_oper_port_key = port->actor_admin_port_key |=
2251 		__get_duplex(port);
2252 	pr_debug("Port %d changed duplex\n", port->actor_port_number);
2253 	// there is no need to reselect a new aggregator, just signal the
2254 	// state machines to reinitialize
2255 	port->sm_vars |= AD_PORT_BEGIN;
2256 }
2257 
2258 /**
2259  * bond_3ad_handle_link_change - handle a slave's link status change indication
2260  * @slave: slave struct to work on
2261  * @status: whether the link is now up or down
2262  *
2263  * Handle reselection of aggregator (if needed) for this port.
2264  */
2265 void bond_3ad_handle_link_change(struct slave *slave, char link)
2266 {
2267 	struct port *port;
2268 
2269 	port = &(SLAVE_AD_INFO(slave).port);
2270 
2271 	// if slave is null, the whole port is not initialized
2272 	if (!port->slave) {
2273 		pr_warning("Warning: %s: link status changed for uninitialized port on %s\n",
2274 			   slave->bond->dev->name, slave->dev->name);
2275 		return;
2276 	}
2277 
2278 	// on link down we are zeroing duplex and speed since some of the adaptors(ce1000.lan) report full duplex/speed instead of N/A(duplex) / 0(speed)
2279 	// on link up we are forcing recheck on the duplex and speed since some of he adaptors(ce1000.lan) report
2280 	if (link == BOND_LINK_UP) {
2281 		port->is_enabled = true;
2282 		port->actor_admin_port_key &= ~AD_DUPLEX_KEY_BITS;
2283 		port->actor_oper_port_key = port->actor_admin_port_key |=
2284 			__get_duplex(port);
2285 		port->actor_admin_port_key &= ~AD_SPEED_KEY_BITS;
2286 		port->actor_oper_port_key = port->actor_admin_port_key |=
2287 			(__get_link_speed(port) << 1);
2288 	} else {
2289 		/* link has failed */
2290 		port->is_enabled = false;
2291 		port->actor_admin_port_key &= ~AD_DUPLEX_KEY_BITS;
2292 		port->actor_oper_port_key = (port->actor_admin_port_key &=
2293 					     ~AD_SPEED_KEY_BITS);
2294 	}
2295 	//BOND_PRINT_DBG(("Port %d changed link status to %s", port->actor_port_number, ((link == BOND_LINK_UP)?"UP":"DOWN")));
2296 	// there is no need to reselect a new aggregator, just signal the
2297 	// state machines to reinitialize
2298 	port->sm_vars |= AD_PORT_BEGIN;
2299 }
2300 
2301 /*
2302  * set link state for bonding master: if we have an active
2303  * aggregator, we're up, if not, we're down.  Presumes that we cannot
2304  * have an active aggregator if there are no slaves with link up.
2305  *
2306  * This behavior complies with IEEE 802.3 section 43.3.9.
2307  *
2308  * Called by bond_set_carrier(). Return zero if carrier state does not
2309  * change, nonzero if it does.
2310  */
2311 int bond_3ad_set_carrier(struct bonding *bond)
2312 {
2313 	struct aggregator *active;
2314 	struct slave *first_slave;
2315 
2316 	rcu_read_lock();
2317 	first_slave = bond_first_slave_rcu(bond);
2318 	rcu_read_unlock();
2319 	if (!first_slave)
2320 		return 0;
2321 	active = __get_active_agg(&(SLAVE_AD_INFO(first_slave).aggregator));
2322 	if (active) {
2323 		/* are enough slaves available to consider link up? */
2324 		if (active->num_of_ports < bond->params.min_links) {
2325 			if (netif_carrier_ok(bond->dev)) {
2326 				netif_carrier_off(bond->dev);
2327 				return 1;
2328 			}
2329 		} else if (!netif_carrier_ok(bond->dev)) {
2330 			netif_carrier_on(bond->dev);
2331 			return 1;
2332 		}
2333 		return 0;
2334 	}
2335 
2336 	if (netif_carrier_ok(bond->dev)) {
2337 		netif_carrier_off(bond->dev);
2338 		return 1;
2339 	}
2340 	return 0;
2341 }
2342 
2343 /**
2344  * __bond_3ad_get_active_agg_info - get information of the active aggregator
2345  * @bond: bonding struct to work on
2346  * @ad_info: ad_info struct to fill with the bond's info
2347  *
2348  * Returns:   0 on success
2349  *          < 0 on error
2350  */
2351 int __bond_3ad_get_active_agg_info(struct bonding *bond,
2352 				   struct ad_info *ad_info)
2353 {
2354 	struct aggregator *aggregator = NULL;
2355 	struct list_head *iter;
2356 	struct slave *slave;
2357 	struct port *port;
2358 
2359 	bond_for_each_slave_rcu(bond, slave, iter) {
2360 		port = &(SLAVE_AD_INFO(slave).port);
2361 		if (port->aggregator && port->aggregator->is_active) {
2362 			aggregator = port->aggregator;
2363 			break;
2364 		}
2365 	}
2366 
2367 	if (aggregator) {
2368 		ad_info->aggregator_id = aggregator->aggregator_identifier;
2369 		ad_info->ports = aggregator->num_of_ports;
2370 		ad_info->actor_key = aggregator->actor_oper_aggregator_key;
2371 		ad_info->partner_key = aggregator->partner_oper_aggregator_key;
2372 		memcpy(ad_info->partner_system, aggregator->partner_system.mac_addr_value, ETH_ALEN);
2373 		return 0;
2374 	}
2375 
2376 	return -1;
2377 }
2378 
2379 /* Wrapper used to hold bond->lock so no slave manipulation can occur */
2380 int bond_3ad_get_active_agg_info(struct bonding *bond, struct ad_info *ad_info)
2381 {
2382 	int ret;
2383 
2384 	rcu_read_lock();
2385 	ret = __bond_3ad_get_active_agg_info(bond, ad_info);
2386 	rcu_read_unlock();
2387 
2388 	return ret;
2389 }
2390 
2391 int bond_3ad_xmit_xor(struct sk_buff *skb, struct net_device *dev)
2392 {
2393 	struct bonding *bond = netdev_priv(dev);
2394 	struct slave *slave, *first_ok_slave;
2395 	struct aggregator *agg;
2396 	struct ad_info ad_info;
2397 	struct list_head *iter;
2398 	int slaves_in_agg;
2399 	int slave_agg_no;
2400 	int res = 1;
2401 	int agg_id;
2402 
2403 	if (__bond_3ad_get_active_agg_info(bond, &ad_info)) {
2404 		pr_debug("%s: Error: __bond_3ad_get_active_agg_info failed\n",
2405 			 dev->name);
2406 		goto out;
2407 	}
2408 
2409 	slaves_in_agg = ad_info.ports;
2410 	agg_id = ad_info.aggregator_id;
2411 
2412 	if (slaves_in_agg == 0) {
2413 		pr_debug("%s: Error: active aggregator is empty\n", dev->name);
2414 		goto out;
2415 	}
2416 
2417 	slave_agg_no = bond_xmit_hash(bond, skb, slaves_in_agg);
2418 	first_ok_slave = NULL;
2419 
2420 	bond_for_each_slave_rcu(bond, slave, iter) {
2421 		agg = SLAVE_AD_INFO(slave).port.aggregator;
2422 		if (!agg || agg->aggregator_identifier != agg_id)
2423 			continue;
2424 
2425 		if (slave_agg_no >= 0) {
2426 			if (!first_ok_slave && SLAVE_IS_OK(slave))
2427 				first_ok_slave = slave;
2428 			slave_agg_no--;
2429 			continue;
2430 		}
2431 
2432 		if (SLAVE_IS_OK(slave)) {
2433 			res = bond_dev_queue_xmit(bond, skb, slave->dev);
2434 			goto out;
2435 		}
2436 	}
2437 
2438 	if (slave_agg_no >= 0) {
2439 		pr_err("%s: Error: Couldn't find a slave to tx on for aggregator ID %d\n",
2440 		       dev->name, agg_id);
2441 		goto out;
2442 	}
2443 
2444 	/* we couldn't find any suitable slave after the agg_no, so use the
2445 	 * first suitable found, if found. */
2446 	if (first_ok_slave)
2447 		res = bond_dev_queue_xmit(bond, skb, first_ok_slave->dev);
2448 
2449 out:
2450 	if (res) {
2451 		/* no suitable interface, frame not sent */
2452 		kfree_skb(skb);
2453 	}
2454 
2455 	return NETDEV_TX_OK;
2456 }
2457 
2458 int bond_3ad_lacpdu_recv(const struct sk_buff *skb, struct bonding *bond,
2459 			 struct slave *slave)
2460 {
2461 	int ret = RX_HANDLER_ANOTHER;
2462 	struct lacpdu *lacpdu, _lacpdu;
2463 
2464 	if (skb->protocol != PKT_TYPE_LACPDU)
2465 		return ret;
2466 
2467 	lacpdu = skb_header_pointer(skb, 0, sizeof(_lacpdu), &_lacpdu);
2468 	if (!lacpdu)
2469 		return ret;
2470 
2471 	read_lock(&bond->lock);
2472 	ret = bond_3ad_rx_indication(lacpdu, slave, skb->len);
2473 	read_unlock(&bond->lock);
2474 	return ret;
2475 }
2476 
2477 /*
2478  * When modify lacp_rate parameter via sysfs,
2479  * update actor_oper_port_state of each port.
2480  *
2481  * Hold slave->state_machine_lock,
2482  * so we can modify port->actor_oper_port_state,
2483  * no matter bond is up or down.
2484  */
2485 void bond_3ad_update_lacp_rate(struct bonding *bond)
2486 {
2487 	struct port *port = NULL;
2488 	struct list_head *iter;
2489 	struct slave *slave;
2490 	int lacp_fast;
2491 
2492 	lacp_fast = bond->params.lacp_fast;
2493 	bond_for_each_slave(bond, slave, iter) {
2494 		port = &(SLAVE_AD_INFO(slave).port);
2495 		__get_state_machine_lock(port);
2496 		if (lacp_fast)
2497 			port->actor_oper_port_state |= AD_STATE_LACP_TIMEOUT;
2498 		else
2499 			port->actor_oper_port_state &= ~AD_STATE_LACP_TIMEOUT;
2500 		__release_state_machine_lock(port);
2501 	}
2502 }
2503