xref: /linux/net/atm/mpc.c (revision ab52c59103002b49f2455371e4b9c56ba3ef1781)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
3 
4 #include <linux/kernel.h>
5 #include <linux/string.h>
6 #include <linux/slab.h>
7 #include <linux/timer.h>
8 #include <linux/init.h>
9 #include <linux/bitops.h>
10 #include <linux/capability.h>
11 #include <linux/seq_file.h>
12 
13 /* We are an ethernet device */
14 #include <linux/if_ether.h>
15 #include <linux/netdevice.h>
16 #include <linux/etherdevice.h>
17 #include <net/sock.h>
18 #include <linux/skbuff.h>
19 #include <linux/ip.h>
20 #include <linux/uaccess.h>
21 #include <asm/byteorder.h>
22 #include <net/checksum.h>   /* for ip_fast_csum() */
23 #include <net/arp.h>
24 #include <net/dst.h>
25 #include <linux/proc_fs.h>
26 
27 /* And atm device */
28 #include <linux/atmdev.h>
29 #include <linux/atmlec.h>
30 #include <linux/atmmpc.h>
31 /* Modular too */
32 #include <linux/module.h>
33 
34 #include "lec.h"
35 #include "mpc.h"
36 #include "resources.h"
37 
38 /*
39  * mpc.c: Implementation of MPOA client kernel part
40  */
41 
42 #if 0
43 #define dprintk(format, args...) \
44 	printk(KERN_DEBUG "mpoa:%s: " format, __func__, ##args)
45 #define dprintk_cont(format, args...) printk(KERN_CONT format, ##args)
46 #else
47 #define dprintk(format, args...)					\
48 	do { if (0)							\
49 		printk(KERN_DEBUG "mpoa:%s: " format, __func__, ##args);\
50 	} while (0)
51 #define dprintk_cont(format, args...)			\
52 	do { if (0) printk(KERN_CONT format, ##args); } while (0)
53 #endif
54 
55 #if 0
56 #define ddprintk(format, args...) \
57 	printk(KERN_DEBUG "mpoa:%s: " format, __func__, ##args)
58 #define ddprintk_cont(format, args...) printk(KERN_CONT format, ##args)
59 #else
60 #define ddprintk(format, args...)					\
61 	do { if (0)							\
62 		printk(KERN_DEBUG "mpoa:%s: " format, __func__, ##args);\
63 	} while (0)
64 #define ddprintk_cont(format, args...)			\
65 	do { if (0) printk(KERN_CONT format, ##args); } while (0)
66 #endif
67 
68 /* mpc_daemon -> kernel */
69 static void MPOA_trigger_rcvd(struct k_message *msg, struct mpoa_client *mpc);
70 static void MPOA_res_reply_rcvd(struct k_message *msg, struct mpoa_client *mpc);
71 static void ingress_purge_rcvd(struct k_message *msg, struct mpoa_client *mpc);
72 static void egress_purge_rcvd(struct k_message *msg, struct mpoa_client *mpc);
73 static void mps_death(struct k_message *msg, struct mpoa_client *mpc);
74 static void clean_up(struct k_message *msg, struct mpoa_client *mpc,
75 		     int action);
76 static void MPOA_cache_impos_rcvd(struct k_message *msg,
77 				  struct mpoa_client *mpc);
78 static void set_mpc_ctrl_addr_rcvd(struct k_message *mesg,
79 				   struct mpoa_client *mpc);
80 static void set_mps_mac_addr_rcvd(struct k_message *mesg,
81 				  struct mpoa_client *mpc);
82 
83 static const uint8_t *copy_macs(struct mpoa_client *mpc,
84 				const uint8_t *router_mac,
85 				const uint8_t *tlvs, uint8_t mps_macs,
86 				uint8_t device_type);
87 static void purge_egress_shortcut(struct atm_vcc *vcc, eg_cache_entry *entry);
88 
89 static void send_set_mps_ctrl_addr(const char *addr, struct mpoa_client *mpc);
90 static void mpoad_close(struct atm_vcc *vcc);
91 static int msg_from_mpoad(struct atm_vcc *vcc, struct sk_buff *skb);
92 
93 static void mpc_push(struct atm_vcc *vcc, struct sk_buff *skb);
94 static netdev_tx_t mpc_send_packet(struct sk_buff *skb,
95 				   struct net_device *dev);
96 static int mpoa_event_listener(struct notifier_block *mpoa_notifier,
97 			       unsigned long event, void *dev);
98 static void mpc_timer_refresh(void);
99 static void mpc_cache_check(struct timer_list *unused);
100 
101 static struct llc_snap_hdr llc_snap_mpoa_ctrl = {
102 	0xaa, 0xaa, 0x03,
103 	{0x00, 0x00, 0x5e},
104 	{0x00, 0x03}         /* For MPOA control PDUs */
105 };
106 static struct llc_snap_hdr llc_snap_mpoa_data = {
107 	0xaa, 0xaa, 0x03,
108 	{0x00, 0x00, 0x00},
109 	{0x08, 0x00}         /* This is for IP PDUs only */
110 };
111 static struct llc_snap_hdr llc_snap_mpoa_data_tagged = {
112 	0xaa, 0xaa, 0x03,
113 	{0x00, 0x00, 0x00},
114 	{0x88, 0x4c}         /* This is for tagged data PDUs */
115 };
116 
117 static struct notifier_block mpoa_notifier = {
118 	mpoa_event_listener,
119 	NULL,
120 	0
121 };
122 
123 struct mpoa_client *mpcs = NULL; /* FIXME */
124 static struct atm_mpoa_qos *qos_head = NULL;
125 static DEFINE_TIMER(mpc_timer, mpc_cache_check);
126 
127 
128 static struct mpoa_client *find_mpc_by_itfnum(int itf)
129 {
130 	struct mpoa_client *mpc;
131 
132 	mpc = mpcs;  /* our global linked list */
133 	while (mpc != NULL) {
134 		if (mpc->dev_num == itf)
135 			return mpc;
136 		mpc = mpc->next;
137 	}
138 
139 	return NULL;   /* not found */
140 }
141 
142 static struct mpoa_client *find_mpc_by_vcc(struct atm_vcc *vcc)
143 {
144 	struct mpoa_client *mpc;
145 
146 	mpc = mpcs;  /* our global linked list */
147 	while (mpc != NULL) {
148 		if (mpc->mpoad_vcc == vcc)
149 			return mpc;
150 		mpc = mpc->next;
151 	}
152 
153 	return NULL;   /* not found */
154 }
155 
156 static struct mpoa_client *find_mpc_by_lec(struct net_device *dev)
157 {
158 	struct mpoa_client *mpc;
159 
160 	mpc = mpcs;  /* our global linked list */
161 	while (mpc != NULL) {
162 		if (mpc->dev == dev)
163 			return mpc;
164 		mpc = mpc->next;
165 	}
166 
167 	return NULL;   /* not found */
168 }
169 
170 /*
171  * Functions for managing QoS list
172  */
173 
174 /*
175  * Overwrites the old entry or makes a new one.
176  */
177 struct atm_mpoa_qos *atm_mpoa_add_qos(__be32 dst_ip, struct atm_qos *qos)
178 {
179 	struct atm_mpoa_qos *entry;
180 
181 	entry = atm_mpoa_search_qos(dst_ip);
182 	if (entry != NULL) {
183 		entry->qos = *qos;
184 		return entry;
185 	}
186 
187 	entry = kmalloc(sizeof(struct atm_mpoa_qos), GFP_KERNEL);
188 	if (entry == NULL) {
189 		pr_info("mpoa: out of memory\n");
190 		return entry;
191 	}
192 
193 	entry->ipaddr = dst_ip;
194 	entry->qos = *qos;
195 
196 	entry->next = qos_head;
197 	qos_head = entry;
198 
199 	return entry;
200 }
201 
202 struct atm_mpoa_qos *atm_mpoa_search_qos(__be32 dst_ip)
203 {
204 	struct atm_mpoa_qos *qos;
205 
206 	qos = qos_head;
207 	while (qos) {
208 		if (qos->ipaddr == dst_ip)
209 			break;
210 		qos = qos->next;
211 	}
212 
213 	return qos;
214 }
215 
216 /*
217  * Returns 0 for failure
218  */
219 int atm_mpoa_delete_qos(struct atm_mpoa_qos *entry)
220 {
221 	struct atm_mpoa_qos *curr;
222 
223 	if (entry == NULL)
224 		return 0;
225 	if (entry == qos_head) {
226 		qos_head = qos_head->next;
227 		kfree(entry);
228 		return 1;
229 	}
230 
231 	curr = qos_head;
232 	while (curr != NULL) {
233 		if (curr->next == entry) {
234 			curr->next = entry->next;
235 			kfree(entry);
236 			return 1;
237 		}
238 		curr = curr->next;
239 	}
240 
241 	return 0;
242 }
243 
244 /* this is buggered - we need locking for qos_head */
245 void atm_mpoa_disp_qos(struct seq_file *m)
246 {
247 	struct atm_mpoa_qos *qos;
248 
249 	qos = qos_head;
250 	seq_printf(m, "QoS entries for shortcuts:\n");
251 	seq_printf(m, "IP address\n  TX:max_pcr pcr     min_pcr max_cdv max_sdu\n  RX:max_pcr pcr     min_pcr max_cdv max_sdu\n");
252 
253 	while (qos != NULL) {
254 		seq_printf(m, "%pI4\n     %-7d %-7d %-7d %-7d %-7d\n     %-7d %-7d %-7d %-7d %-7d\n",
255 			   &qos->ipaddr,
256 			   qos->qos.txtp.max_pcr,
257 			   qos->qos.txtp.pcr,
258 			   qos->qos.txtp.min_pcr,
259 			   qos->qos.txtp.max_cdv,
260 			   qos->qos.txtp.max_sdu,
261 			   qos->qos.rxtp.max_pcr,
262 			   qos->qos.rxtp.pcr,
263 			   qos->qos.rxtp.min_pcr,
264 			   qos->qos.rxtp.max_cdv,
265 			   qos->qos.rxtp.max_sdu);
266 		qos = qos->next;
267 	}
268 }
269 
270 static struct net_device *find_lec_by_itfnum(int itf)
271 {
272 	struct net_device *dev;
273 	char name[IFNAMSIZ];
274 
275 	sprintf(name, "lec%d", itf);
276 	dev = dev_get_by_name(&init_net, name);
277 
278 	return dev;
279 }
280 
281 static struct mpoa_client *alloc_mpc(void)
282 {
283 	struct mpoa_client *mpc;
284 
285 	mpc = kzalloc(sizeof(struct mpoa_client), GFP_KERNEL);
286 	if (mpc == NULL)
287 		return NULL;
288 	rwlock_init(&mpc->ingress_lock);
289 	rwlock_init(&mpc->egress_lock);
290 	mpc->next = mpcs;
291 	atm_mpoa_init_cache(mpc);
292 
293 	mpc->parameters.mpc_p1 = MPC_P1;
294 	mpc->parameters.mpc_p2 = MPC_P2;
295 	memset(mpc->parameters.mpc_p3, 0, sizeof(mpc->parameters.mpc_p3));
296 	mpc->parameters.mpc_p4 = MPC_P4;
297 	mpc->parameters.mpc_p5 = MPC_P5;
298 	mpc->parameters.mpc_p6 = MPC_P6;
299 
300 	mpcs = mpc;
301 
302 	return mpc;
303 }
304 
305 /*
306  *
307  * start_mpc() puts the MPC on line. All the packets destined
308  * to the lec underneath us are now being monitored and
309  * shortcuts will be established.
310  *
311  */
312 static void start_mpc(struct mpoa_client *mpc, struct net_device *dev)
313 {
314 
315 	dprintk("(%s)\n", mpc->dev->name);
316 	if (!dev->netdev_ops)
317 		pr_info("(%s) not starting\n", dev->name);
318 	else {
319 		mpc->old_ops = dev->netdev_ops;
320 		mpc->new_ops = *mpc->old_ops;
321 		mpc->new_ops.ndo_start_xmit = mpc_send_packet;
322 		dev->netdev_ops = &mpc->new_ops;
323 	}
324 }
325 
326 static void stop_mpc(struct mpoa_client *mpc)
327 {
328 	struct net_device *dev = mpc->dev;
329 	dprintk("(%s)", mpc->dev->name);
330 
331 	/* Lets not nullify lec device's dev->hard_start_xmit */
332 	if (dev->netdev_ops != &mpc->new_ops) {
333 		dprintk_cont(" mpc already stopped, not fatal\n");
334 		return;
335 	}
336 	dprintk_cont("\n");
337 
338 	dev->netdev_ops = mpc->old_ops;
339 	mpc->old_ops = NULL;
340 
341 	/* close_shortcuts(mpc);    ??? FIXME */
342 }
343 
344 static const char *mpoa_device_type_string(char type) __attribute__ ((unused));
345 
346 static const char *mpoa_device_type_string(char type)
347 {
348 	switch (type) {
349 	case NON_MPOA:
350 		return "non-MPOA device";
351 	case MPS:
352 		return "MPS";
353 	case MPC:
354 		return "MPC";
355 	case MPS_AND_MPC:
356 		return "both MPS and MPC";
357 	}
358 
359 	return "unspecified (non-MPOA) device";
360 }
361 
362 /*
363  * lec device calls this via its netdev_priv(dev)->lane2_ops
364  * ->associate_indicator() when it sees a TLV in LE_ARP packet.
365  * We fill in the pointer above when we see a LANE2 lec initializing
366  * See LANE2 spec 3.1.5
367  *
368  * Quite a big and ugly function but when you look at it
369  * all it does is to try to locate and parse MPOA Device
370  * Type TLV.
371  * We give our lec a pointer to this function and when the
372  * lec sees a TLV it uses the pointer to call this function.
373  *
374  */
375 static void lane2_assoc_ind(struct net_device *dev, const u8 *mac_addr,
376 			    const u8 *tlvs, u32 sizeoftlvs)
377 {
378 	uint32_t type;
379 	uint8_t length, mpoa_device_type, number_of_mps_macs;
380 	const uint8_t *end_of_tlvs;
381 	struct mpoa_client *mpc;
382 
383 	mpoa_device_type = number_of_mps_macs = 0; /* silence gcc */
384 	dprintk("(%s) received TLV(s), ", dev->name);
385 	dprintk("total length of all TLVs %d\n", sizeoftlvs);
386 	mpc = find_mpc_by_lec(dev); /* Sampo-Fix: moved here from below */
387 	if (mpc == NULL) {
388 		pr_info("(%s) no mpc\n", dev->name);
389 		return;
390 	}
391 	end_of_tlvs = tlvs + sizeoftlvs;
392 	while (end_of_tlvs - tlvs >= 5) {
393 		type = ((tlvs[0] << 24) | (tlvs[1] << 16) |
394 			(tlvs[2] << 8) | tlvs[3]);
395 		length = tlvs[4];
396 		tlvs += 5;
397 		dprintk("    type 0x%x length %02x\n", type, length);
398 		if (tlvs + length > end_of_tlvs) {
399 			pr_info("TLV value extends past its buffer, aborting parse\n");
400 			return;
401 		}
402 
403 		if (type == 0) {
404 			pr_info("mpoa: (%s) TLV type was 0, returning\n",
405 				dev->name);
406 			return;
407 		}
408 
409 		if (type != TLV_MPOA_DEVICE_TYPE) {
410 			tlvs += length;
411 			continue;  /* skip other TLVs */
412 		}
413 		mpoa_device_type = *tlvs++;
414 		number_of_mps_macs = *tlvs++;
415 		dprintk("(%s) MPOA device type '%s', ",
416 			dev->name, mpoa_device_type_string(mpoa_device_type));
417 		if (mpoa_device_type == MPS_AND_MPC &&
418 		    length < (42 + number_of_mps_macs*ETH_ALEN)) { /* :) */
419 			pr_info("(%s) short MPOA Device Type TLV\n",
420 				dev->name);
421 			continue;
422 		}
423 		if ((mpoa_device_type == MPS || mpoa_device_type == MPC) &&
424 		    length < 22 + number_of_mps_macs*ETH_ALEN) {
425 			pr_info("(%s) short MPOA Device Type TLV\n", dev->name);
426 			continue;
427 		}
428 		if (mpoa_device_type != MPS &&
429 		    mpoa_device_type != MPS_AND_MPC) {
430 			dprintk("ignoring non-MPS device ");
431 			if (mpoa_device_type == MPC)
432 				tlvs += 20;
433 			continue;  /* we are only interested in MPSs */
434 		}
435 		if (number_of_mps_macs == 0 &&
436 		    mpoa_device_type == MPS_AND_MPC) {
437 			pr_info("(%s) MPS_AND_MPC has zero MACs\n", dev->name);
438 			continue;  /* someone should read the spec */
439 		}
440 		dprintk_cont("this MPS has %d MAC addresses\n",
441 			     number_of_mps_macs);
442 
443 		/*
444 		 * ok, now we can go and tell our daemon
445 		 * the control address of MPS
446 		 */
447 		send_set_mps_ctrl_addr(tlvs, mpc);
448 
449 		tlvs = copy_macs(mpc, mac_addr, tlvs,
450 				 number_of_mps_macs, mpoa_device_type);
451 		if (tlvs == NULL)
452 			return;
453 	}
454 	if (end_of_tlvs - tlvs != 0)
455 		pr_info("(%s) ignoring %zd bytes of trailing TLV garbage\n",
456 			dev->name, end_of_tlvs - tlvs);
457 }
458 
459 /*
460  * Store at least advertizing router's MAC address
461  * plus the possible MAC address(es) to mpc->mps_macs.
462  * For a freshly allocated MPOA client mpc->mps_macs == 0.
463  */
464 static const uint8_t *copy_macs(struct mpoa_client *mpc,
465 				const uint8_t *router_mac,
466 				const uint8_t *tlvs, uint8_t mps_macs,
467 				uint8_t device_type)
468 {
469 	int num_macs;
470 	num_macs = (mps_macs > 1) ? mps_macs : 1;
471 
472 	if (mpc->number_of_mps_macs != num_macs) { /* need to reallocate? */
473 		if (mpc->number_of_mps_macs != 0)
474 			kfree(mpc->mps_macs);
475 		mpc->number_of_mps_macs = 0;
476 		mpc->mps_macs = kmalloc_array(ETH_ALEN, num_macs, GFP_KERNEL);
477 		if (mpc->mps_macs == NULL) {
478 			pr_info("(%s) out of mem\n", mpc->dev->name);
479 			return NULL;
480 		}
481 	}
482 	ether_addr_copy(mpc->mps_macs, router_mac);
483 	tlvs += 20; if (device_type == MPS_AND_MPC) tlvs += 20;
484 	if (mps_macs > 0)
485 		memcpy(mpc->mps_macs, tlvs, mps_macs*ETH_ALEN);
486 	tlvs += mps_macs*ETH_ALEN;
487 	mpc->number_of_mps_macs = num_macs;
488 
489 	return tlvs;
490 }
491 
492 static int send_via_shortcut(struct sk_buff *skb, struct mpoa_client *mpc)
493 {
494 	in_cache_entry *entry;
495 	struct iphdr *iph;
496 	char *buff;
497 	__be32 ipaddr = 0;
498 
499 	static struct {
500 		struct llc_snap_hdr hdr;
501 		__be32 tag;
502 	} tagged_llc_snap_hdr = {
503 		{0xaa, 0xaa, 0x03, {0x00, 0x00, 0x00}, {0x88, 0x4c}},
504 		0
505 	};
506 
507 	buff = skb->data + mpc->dev->hard_header_len;
508 	iph = (struct iphdr *)buff;
509 	ipaddr = iph->daddr;
510 
511 	ddprintk("(%s) ipaddr 0x%x\n",
512 		 mpc->dev->name, ipaddr);
513 
514 	entry = mpc->in_ops->get(ipaddr, mpc);
515 	if (entry == NULL) {
516 		entry = mpc->in_ops->add_entry(ipaddr, mpc);
517 		if (entry != NULL)
518 			mpc->in_ops->put(entry);
519 		return 1;
520 	}
521 	/* threshold not exceeded or VCC not ready */
522 	if (mpc->in_ops->cache_hit(entry, mpc) != OPEN) {
523 		ddprintk("(%s) cache_hit: returns != OPEN\n",
524 			 mpc->dev->name);
525 		mpc->in_ops->put(entry);
526 		return 1;
527 	}
528 
529 	ddprintk("(%s) using shortcut\n",
530 		 mpc->dev->name);
531 	/* MPOA spec A.1.4, MPOA client must decrement IP ttl at least by one */
532 	if (iph->ttl <= 1) {
533 		ddprintk("(%s) IP ttl = %u, using LANE\n",
534 			 mpc->dev->name, iph->ttl);
535 		mpc->in_ops->put(entry);
536 		return 1;
537 	}
538 	iph->ttl--;
539 	iph->check = 0;
540 	iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl);
541 
542 	if (entry->ctrl_info.tag != 0) {
543 		ddprintk("(%s) adding tag 0x%x\n",
544 			 mpc->dev->name, entry->ctrl_info.tag);
545 		tagged_llc_snap_hdr.tag = entry->ctrl_info.tag;
546 		skb_pull(skb, ETH_HLEN);	/* get rid of Eth header */
547 		skb_push(skb, sizeof(tagged_llc_snap_hdr));
548 						/* add LLC/SNAP header   */
549 		skb_copy_to_linear_data(skb, &tagged_llc_snap_hdr,
550 					sizeof(tagged_llc_snap_hdr));
551 	} else {
552 		skb_pull(skb, ETH_HLEN);	/* get rid of Eth header */
553 		skb_push(skb, sizeof(struct llc_snap_hdr));
554 						/* add LLC/SNAP header + tag  */
555 		skb_copy_to_linear_data(skb, &llc_snap_mpoa_data,
556 					sizeof(struct llc_snap_hdr));
557 	}
558 
559 	atm_account_tx(entry->shortcut, skb);
560 	entry->shortcut->send(entry->shortcut, skb);
561 	entry->packets_fwded++;
562 	mpc->in_ops->put(entry);
563 
564 	return 0;
565 }
566 
567 /*
568  * Probably needs some error checks and locking, not sure...
569  */
570 static netdev_tx_t mpc_send_packet(struct sk_buff *skb,
571 					 struct net_device *dev)
572 {
573 	struct mpoa_client *mpc;
574 	struct ethhdr *eth;
575 	int i = 0;
576 
577 	mpc = find_mpc_by_lec(dev); /* this should NEVER fail */
578 	if (mpc == NULL) {
579 		pr_info("(%s) no MPC found\n", dev->name);
580 		goto non_ip;
581 	}
582 
583 	eth = (struct ethhdr *)skb->data;
584 	if (eth->h_proto != htons(ETH_P_IP))
585 		goto non_ip; /* Multi-Protocol Over ATM :-) */
586 
587 	/* Weed out funny packets (e.g., AF_PACKET or raw). */
588 	if (skb->len < ETH_HLEN + sizeof(struct iphdr))
589 		goto non_ip;
590 	skb_set_network_header(skb, ETH_HLEN);
591 	if (skb->len < ETH_HLEN + ip_hdr(skb)->ihl * 4 || ip_hdr(skb)->ihl < 5)
592 		goto non_ip;
593 
594 	while (i < mpc->number_of_mps_macs) {
595 		if (ether_addr_equal(eth->h_dest, mpc->mps_macs + i * ETH_ALEN))
596 			if (send_via_shortcut(skb, mpc) == 0) /* try shortcut */
597 				return NETDEV_TX_OK;
598 		i++;
599 	}
600 
601 non_ip:
602 	return __netdev_start_xmit(mpc->old_ops, skb, dev, false);
603 }
604 
605 static int atm_mpoa_vcc_attach(struct atm_vcc *vcc, void __user *arg)
606 {
607 	int bytes_left;
608 	struct mpoa_client *mpc;
609 	struct atmmpc_ioc ioc_data;
610 	in_cache_entry *in_entry;
611 	__be32  ipaddr;
612 
613 	bytes_left = copy_from_user(&ioc_data, arg, sizeof(struct atmmpc_ioc));
614 	if (bytes_left != 0) {
615 		pr_info("mpoa:Short read (missed %d bytes) from userland\n",
616 			bytes_left);
617 		return -EFAULT;
618 	}
619 	ipaddr = ioc_data.ipaddr;
620 	if (ioc_data.dev_num < 0 || ioc_data.dev_num >= MAX_LEC_ITF)
621 		return -EINVAL;
622 
623 	mpc = find_mpc_by_itfnum(ioc_data.dev_num);
624 	if (mpc == NULL)
625 		return -EINVAL;
626 
627 	if (ioc_data.type == MPC_SOCKET_INGRESS) {
628 		in_entry = mpc->in_ops->get(ipaddr, mpc);
629 		if (in_entry == NULL ||
630 		    in_entry->entry_state < INGRESS_RESOLVED) {
631 			pr_info("(%s) did not find RESOLVED entry from ingress cache\n",
632 				mpc->dev->name);
633 			if (in_entry != NULL)
634 				mpc->in_ops->put(in_entry);
635 			return -EINVAL;
636 		}
637 		pr_info("(%s) attaching ingress SVC, entry = %pI4\n",
638 			mpc->dev->name, &in_entry->ctrl_info.in_dst_ip);
639 		in_entry->shortcut = vcc;
640 		mpc->in_ops->put(in_entry);
641 	} else {
642 		pr_info("(%s) attaching egress SVC\n", mpc->dev->name);
643 	}
644 
645 	vcc->proto_data = mpc->dev;
646 	vcc->push = mpc_push;
647 
648 	return 0;
649 }
650 
651 /*
652  *
653  */
654 static void mpc_vcc_close(struct atm_vcc *vcc, struct net_device *dev)
655 {
656 	struct mpoa_client *mpc;
657 	in_cache_entry *in_entry;
658 	eg_cache_entry *eg_entry;
659 
660 	mpc = find_mpc_by_lec(dev);
661 	if (mpc == NULL) {
662 		pr_info("(%s) close for unknown MPC\n", dev->name);
663 		return;
664 	}
665 
666 	dprintk("(%s)\n", dev->name);
667 	in_entry = mpc->in_ops->get_by_vcc(vcc, mpc);
668 	if (in_entry) {
669 		dprintk("(%s) ingress SVC closed ip = %pI4\n",
670 			mpc->dev->name, &in_entry->ctrl_info.in_dst_ip);
671 		in_entry->shortcut = NULL;
672 		mpc->in_ops->put(in_entry);
673 	}
674 	eg_entry = mpc->eg_ops->get_by_vcc(vcc, mpc);
675 	if (eg_entry) {
676 		dprintk("(%s) egress SVC closed\n", mpc->dev->name);
677 		eg_entry->shortcut = NULL;
678 		mpc->eg_ops->put(eg_entry);
679 	}
680 
681 	if (in_entry == NULL && eg_entry == NULL)
682 		dprintk("(%s) unused vcc closed\n", dev->name);
683 }
684 
685 static void mpc_push(struct atm_vcc *vcc, struct sk_buff *skb)
686 {
687 	struct net_device *dev = (struct net_device *)vcc->proto_data;
688 	struct sk_buff *new_skb;
689 	eg_cache_entry *eg;
690 	struct mpoa_client *mpc;
691 	__be32 tag;
692 	char *tmp;
693 
694 	ddprintk("(%s)\n", dev->name);
695 	if (skb == NULL) {
696 		dprintk("(%s) null skb, closing VCC\n", dev->name);
697 		mpc_vcc_close(vcc, dev);
698 		return;
699 	}
700 
701 	skb->dev = dev;
702 	if (memcmp(skb->data, &llc_snap_mpoa_ctrl,
703 		   sizeof(struct llc_snap_hdr)) == 0) {
704 		struct sock *sk = sk_atm(vcc);
705 
706 		dprintk("(%s) control packet arrived\n", dev->name);
707 		/* Pass control packets to daemon */
708 		skb_queue_tail(&sk->sk_receive_queue, skb);
709 		sk->sk_data_ready(sk);
710 		return;
711 	}
712 
713 	/* data coming over the shortcut */
714 	atm_return(vcc, skb->truesize);
715 
716 	mpc = find_mpc_by_lec(dev);
717 	if (mpc == NULL) {
718 		pr_info("(%s) unknown MPC\n", dev->name);
719 		return;
720 	}
721 
722 	if (memcmp(skb->data, &llc_snap_mpoa_data_tagged,
723 		   sizeof(struct llc_snap_hdr)) == 0) { /* MPOA tagged data */
724 		ddprintk("(%s) tagged data packet arrived\n", dev->name);
725 
726 	} else if (memcmp(skb->data, &llc_snap_mpoa_data,
727 			  sizeof(struct llc_snap_hdr)) == 0) { /* MPOA data */
728 		pr_info("(%s) Unsupported non-tagged data packet arrived.  Purging\n",
729 			dev->name);
730 		dev_kfree_skb_any(skb);
731 		return;
732 	} else {
733 		pr_info("(%s) garbage arrived, purging\n", dev->name);
734 		dev_kfree_skb_any(skb);
735 		return;
736 	}
737 
738 	tmp = skb->data + sizeof(struct llc_snap_hdr);
739 	tag = *(__be32 *)tmp;
740 
741 	eg = mpc->eg_ops->get_by_tag(tag, mpc);
742 	if (eg == NULL) {
743 		pr_info("mpoa: (%s) Didn't find egress cache entry, tag = %u\n",
744 			dev->name, tag);
745 		purge_egress_shortcut(vcc, NULL);
746 		dev_kfree_skb_any(skb);
747 		return;
748 	}
749 
750 	/*
751 	 * See if ingress MPC is using shortcut we opened as a return channel.
752 	 * This means we have a bi-directional vcc opened by us.
753 	 */
754 	if (eg->shortcut == NULL) {
755 		eg->shortcut = vcc;
756 		pr_info("(%s) egress SVC in use\n", dev->name);
757 	}
758 
759 	skb_pull(skb, sizeof(struct llc_snap_hdr) + sizeof(tag));
760 					/* get rid of LLC/SNAP header */
761 	new_skb = skb_realloc_headroom(skb, eg->ctrl_info.DH_length);
762 					/* LLC/SNAP is shorter than MAC header :( */
763 	dev_kfree_skb_any(skb);
764 	if (new_skb == NULL) {
765 		mpc->eg_ops->put(eg);
766 		return;
767 	}
768 	skb_push(new_skb, eg->ctrl_info.DH_length);     /* add MAC header */
769 	skb_copy_to_linear_data(new_skb, eg->ctrl_info.DLL_header,
770 				eg->ctrl_info.DH_length);
771 	new_skb->protocol = eth_type_trans(new_skb, dev);
772 	skb_reset_network_header(new_skb);
773 
774 	eg->latest_ip_addr = ip_hdr(new_skb)->saddr;
775 	eg->packets_rcvd++;
776 	mpc->eg_ops->put(eg);
777 
778 	memset(ATM_SKB(new_skb), 0, sizeof(struct atm_skb_data));
779 	netif_rx(new_skb);
780 }
781 
782 static const struct atmdev_ops mpc_ops = { /* only send is required */
783 	.close	= mpoad_close,
784 	.send	= msg_from_mpoad
785 };
786 
787 static struct atm_dev mpc_dev = {
788 	.ops	= &mpc_ops,
789 	.type	= "mpc",
790 	.number	= 42,
791 	.lock	= __SPIN_LOCK_UNLOCKED(mpc_dev.lock)
792 	/* members not explicitly initialised will be 0 */
793 };
794 
795 static int atm_mpoa_mpoad_attach(struct atm_vcc *vcc, int arg)
796 {
797 	struct mpoa_client *mpc;
798 	struct lec_priv *priv;
799 	int err;
800 
801 	if (mpcs == NULL) {
802 		mpc_timer_refresh();
803 
804 		/* This lets us now how our LECs are doing */
805 		err = register_netdevice_notifier(&mpoa_notifier);
806 		if (err < 0) {
807 			del_timer(&mpc_timer);
808 			return err;
809 		}
810 	}
811 
812 	mpc = find_mpc_by_itfnum(arg);
813 	if (mpc == NULL) {
814 		dprintk("allocating new mpc for itf %d\n", arg);
815 		mpc = alloc_mpc();
816 		if (mpc == NULL)
817 			return -ENOMEM;
818 		mpc->dev_num = arg;
819 		mpc->dev = find_lec_by_itfnum(arg);
820 					/* NULL if there was no lec */
821 	}
822 	if (mpc->mpoad_vcc) {
823 		pr_info("mpoad is already present for itf %d\n", arg);
824 		return -EADDRINUSE;
825 	}
826 
827 	if (mpc->dev) { /* check if the lec is LANE2 capable */
828 		priv = netdev_priv(mpc->dev);
829 		if (priv->lane_version < 2) {
830 			dev_put(mpc->dev);
831 			mpc->dev = NULL;
832 		} else
833 			priv->lane2_ops->associate_indicator = lane2_assoc_ind;
834 	}
835 
836 	mpc->mpoad_vcc = vcc;
837 	vcc->dev = &mpc_dev;
838 	vcc_insert_socket(sk_atm(vcc));
839 	set_bit(ATM_VF_META, &vcc->flags);
840 	set_bit(ATM_VF_READY, &vcc->flags);
841 
842 	if (mpc->dev) {
843 		char empty[ATM_ESA_LEN];
844 		memset(empty, 0, ATM_ESA_LEN);
845 
846 		start_mpc(mpc, mpc->dev);
847 		/* set address if mpcd e.g. gets killed and restarted.
848 		 * If we do not do it now we have to wait for the next LE_ARP
849 		 */
850 		if (memcmp(mpc->mps_ctrl_addr, empty, ATM_ESA_LEN) != 0)
851 			send_set_mps_ctrl_addr(mpc->mps_ctrl_addr, mpc);
852 	}
853 
854 	__module_get(THIS_MODULE);
855 	return arg;
856 }
857 
858 static void send_set_mps_ctrl_addr(const char *addr, struct mpoa_client *mpc)
859 {
860 	struct k_message mesg;
861 
862 	memcpy(mpc->mps_ctrl_addr, addr, ATM_ESA_LEN);
863 
864 	mesg.type = SET_MPS_CTRL_ADDR;
865 	memcpy(mesg.MPS_ctrl, addr, ATM_ESA_LEN);
866 	msg_to_mpoad(&mesg, mpc);
867 }
868 
869 static void mpoad_close(struct atm_vcc *vcc)
870 {
871 	struct mpoa_client *mpc;
872 	struct sk_buff *skb;
873 
874 	mpc = find_mpc_by_vcc(vcc);
875 	if (mpc == NULL) {
876 		pr_info("did not find MPC\n");
877 		return;
878 	}
879 	if (!mpc->mpoad_vcc) {
880 		pr_info("close for non-present mpoad\n");
881 		return;
882 	}
883 
884 	mpc->mpoad_vcc = NULL;
885 	if (mpc->dev) {
886 		struct lec_priv *priv = netdev_priv(mpc->dev);
887 		priv->lane2_ops->associate_indicator = NULL;
888 		stop_mpc(mpc);
889 		dev_put(mpc->dev);
890 	}
891 
892 	mpc->in_ops->destroy_cache(mpc);
893 	mpc->eg_ops->destroy_cache(mpc);
894 
895 	while ((skb = skb_dequeue(&sk_atm(vcc)->sk_receive_queue))) {
896 		atm_return(vcc, skb->truesize);
897 		kfree_skb(skb);
898 	}
899 
900 	pr_info("(%s) going down\n",
901 		(mpc->dev) ? mpc->dev->name : "<unknown>");
902 	module_put(THIS_MODULE);
903 }
904 
905 /*
906  *
907  */
908 static int msg_from_mpoad(struct atm_vcc *vcc, struct sk_buff *skb)
909 {
910 
911 	struct mpoa_client *mpc = find_mpc_by_vcc(vcc);
912 	struct k_message *mesg = (struct k_message *)skb->data;
913 	WARN_ON(refcount_sub_and_test(skb->truesize, &sk_atm(vcc)->sk_wmem_alloc));
914 
915 	if (mpc == NULL) {
916 		pr_info("no mpc found\n");
917 		return 0;
918 	}
919 	dprintk("(%s)", mpc->dev ? mpc->dev->name : "<unknown>");
920 	switch (mesg->type) {
921 	case MPOA_RES_REPLY_RCVD:
922 		dprintk_cont("mpoa_res_reply_rcvd\n");
923 		MPOA_res_reply_rcvd(mesg, mpc);
924 		break;
925 	case MPOA_TRIGGER_RCVD:
926 		dprintk_cont("mpoa_trigger_rcvd\n");
927 		MPOA_trigger_rcvd(mesg, mpc);
928 		break;
929 	case INGRESS_PURGE_RCVD:
930 		dprintk_cont("nhrp_purge_rcvd\n");
931 		ingress_purge_rcvd(mesg, mpc);
932 		break;
933 	case EGRESS_PURGE_RCVD:
934 		dprintk_cont("egress_purge_reply_rcvd\n");
935 		egress_purge_rcvd(mesg, mpc);
936 		break;
937 	case MPS_DEATH:
938 		dprintk_cont("mps_death\n");
939 		mps_death(mesg, mpc);
940 		break;
941 	case CACHE_IMPOS_RCVD:
942 		dprintk_cont("cache_impos_rcvd\n");
943 		MPOA_cache_impos_rcvd(mesg, mpc);
944 		break;
945 	case SET_MPC_CTRL_ADDR:
946 		dprintk_cont("set_mpc_ctrl_addr\n");
947 		set_mpc_ctrl_addr_rcvd(mesg, mpc);
948 		break;
949 	case SET_MPS_MAC_ADDR:
950 		dprintk_cont("set_mps_mac_addr\n");
951 		set_mps_mac_addr_rcvd(mesg, mpc);
952 		break;
953 	case CLEAN_UP_AND_EXIT:
954 		dprintk_cont("clean_up_and_exit\n");
955 		clean_up(mesg, mpc, DIE);
956 		break;
957 	case RELOAD:
958 		dprintk_cont("reload\n");
959 		clean_up(mesg, mpc, RELOAD);
960 		break;
961 	case SET_MPC_PARAMS:
962 		dprintk_cont("set_mpc_params\n");
963 		mpc->parameters = mesg->content.params;
964 		break;
965 	default:
966 		dprintk_cont("unknown message %d\n", mesg->type);
967 		break;
968 	}
969 	kfree_skb(skb);
970 
971 	return 0;
972 }
973 
974 /* Remember that this function may not do things that sleep */
975 int msg_to_mpoad(struct k_message *mesg, struct mpoa_client *mpc)
976 {
977 	struct sk_buff *skb;
978 	struct sock *sk;
979 
980 	if (mpc == NULL || !mpc->mpoad_vcc) {
981 		pr_info("mesg %d to a non-existent mpoad\n", mesg->type);
982 		return -ENXIO;
983 	}
984 
985 	skb = alloc_skb(sizeof(struct k_message), GFP_ATOMIC);
986 	if (skb == NULL)
987 		return -ENOMEM;
988 	skb_put(skb, sizeof(struct k_message));
989 	skb_copy_to_linear_data(skb, mesg, sizeof(*mesg));
990 	atm_force_charge(mpc->mpoad_vcc, skb->truesize);
991 
992 	sk = sk_atm(mpc->mpoad_vcc);
993 	skb_queue_tail(&sk->sk_receive_queue, skb);
994 	sk->sk_data_ready(sk);
995 
996 	return 0;
997 }
998 
999 static int mpoa_event_listener(struct notifier_block *mpoa_notifier,
1000 			       unsigned long event, void *ptr)
1001 {
1002 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
1003 	struct mpoa_client *mpc;
1004 	struct lec_priv *priv;
1005 
1006 	if (!net_eq(dev_net(dev), &init_net))
1007 		return NOTIFY_DONE;
1008 
1009 	if (strncmp(dev->name, "lec", 3))
1010 		return NOTIFY_DONE; /* we are only interested in lec:s */
1011 
1012 	switch (event) {
1013 	case NETDEV_REGISTER:       /* a new lec device was allocated */
1014 		priv = netdev_priv(dev);
1015 		if (priv->lane_version < 2)
1016 			break;
1017 		priv->lane2_ops->associate_indicator = lane2_assoc_ind;
1018 		mpc = find_mpc_by_itfnum(priv->itfnum);
1019 		if (mpc == NULL) {
1020 			dprintk("allocating new mpc for %s\n", dev->name);
1021 			mpc = alloc_mpc();
1022 			if (mpc == NULL) {
1023 				pr_info("no new mpc");
1024 				break;
1025 			}
1026 		}
1027 		mpc->dev_num = priv->itfnum;
1028 		mpc->dev = dev;
1029 		dev_hold(dev);
1030 		dprintk("(%s) was initialized\n", dev->name);
1031 		break;
1032 	case NETDEV_UNREGISTER:
1033 		/* the lec device was deallocated */
1034 		mpc = find_mpc_by_lec(dev);
1035 		if (mpc == NULL)
1036 			break;
1037 		dprintk("device (%s) was deallocated\n", dev->name);
1038 		stop_mpc(mpc);
1039 		dev_put(mpc->dev);
1040 		mpc->dev = NULL;
1041 		break;
1042 	case NETDEV_UP:
1043 		/* the dev was ifconfig'ed up */
1044 		mpc = find_mpc_by_lec(dev);
1045 		if (mpc == NULL)
1046 			break;
1047 		if (mpc->mpoad_vcc != NULL)
1048 			start_mpc(mpc, dev);
1049 		break;
1050 	case NETDEV_DOWN:
1051 		/* the dev was ifconfig'ed down */
1052 		/* this means that the flow of packets from the
1053 		 * upper layer stops
1054 		 */
1055 		mpc = find_mpc_by_lec(dev);
1056 		if (mpc == NULL)
1057 			break;
1058 		if (mpc->mpoad_vcc != NULL)
1059 			stop_mpc(mpc);
1060 		break;
1061 	case NETDEV_REBOOT:
1062 	case NETDEV_CHANGE:
1063 	case NETDEV_CHANGEMTU:
1064 	case NETDEV_CHANGEADDR:
1065 	case NETDEV_GOING_DOWN:
1066 		break;
1067 	default:
1068 		break;
1069 	}
1070 
1071 	return NOTIFY_DONE;
1072 }
1073 
1074 /*
1075  * Functions which are called after a message is received from mpcd.
1076  * Msg is reused on purpose.
1077  */
1078 
1079 
1080 static void MPOA_trigger_rcvd(struct k_message *msg, struct mpoa_client *mpc)
1081 {
1082 	__be32 dst_ip = msg->content.in_info.in_dst_ip;
1083 	in_cache_entry *entry;
1084 
1085 	entry = mpc->in_ops->get(dst_ip, mpc);
1086 	if (entry == NULL) {
1087 		entry = mpc->in_ops->add_entry(dst_ip, mpc);
1088 		entry->entry_state = INGRESS_RESOLVING;
1089 		msg->type = SND_MPOA_RES_RQST;
1090 		msg->content.in_info = entry->ctrl_info;
1091 		msg_to_mpoad(msg, mpc);
1092 		entry->reply_wait = ktime_get_seconds();
1093 		mpc->in_ops->put(entry);
1094 		return;
1095 	}
1096 
1097 	if (entry->entry_state == INGRESS_INVALID) {
1098 		entry->entry_state = INGRESS_RESOLVING;
1099 		msg->type = SND_MPOA_RES_RQST;
1100 		msg->content.in_info = entry->ctrl_info;
1101 		msg_to_mpoad(msg, mpc);
1102 		entry->reply_wait = ktime_get_seconds();
1103 		mpc->in_ops->put(entry);
1104 		return;
1105 	}
1106 
1107 	pr_info("(%s) entry already in resolving state\n",
1108 		(mpc->dev) ? mpc->dev->name : "<unknown>");
1109 	mpc->in_ops->put(entry);
1110 }
1111 
1112 /*
1113  * Things get complicated because we have to check if there's an egress
1114  * shortcut with suitable traffic parameters we could use.
1115  */
1116 static void check_qos_and_open_shortcut(struct k_message *msg,
1117 					struct mpoa_client *client,
1118 					in_cache_entry *entry)
1119 {
1120 	__be32 dst_ip = msg->content.in_info.in_dst_ip;
1121 	struct atm_mpoa_qos *qos = atm_mpoa_search_qos(dst_ip);
1122 	eg_cache_entry *eg_entry = client->eg_ops->get_by_src_ip(dst_ip, client);
1123 
1124 	if (eg_entry && eg_entry->shortcut) {
1125 		if (eg_entry->shortcut->qos.txtp.traffic_class &
1126 		    msg->qos.txtp.traffic_class &
1127 		    (qos ? qos->qos.txtp.traffic_class : ATM_UBR | ATM_CBR)) {
1128 			if (eg_entry->shortcut->qos.txtp.traffic_class == ATM_UBR)
1129 				entry->shortcut = eg_entry->shortcut;
1130 			else if (eg_entry->shortcut->qos.txtp.max_pcr > 0)
1131 				entry->shortcut = eg_entry->shortcut;
1132 		}
1133 		if (entry->shortcut) {
1134 			dprintk("(%s) using egress SVC to reach %pI4\n",
1135 				client->dev->name, &dst_ip);
1136 			client->eg_ops->put(eg_entry);
1137 			return;
1138 		}
1139 	}
1140 	if (eg_entry != NULL)
1141 		client->eg_ops->put(eg_entry);
1142 
1143 	/* No luck in the egress cache we must open an ingress SVC */
1144 	msg->type = OPEN_INGRESS_SVC;
1145 	if (qos &&
1146 	    (qos->qos.txtp.traffic_class == msg->qos.txtp.traffic_class)) {
1147 		msg->qos = qos->qos;
1148 		pr_info("(%s) trying to get a CBR shortcut\n",
1149 			client->dev->name);
1150 	} else
1151 		memset(&msg->qos, 0, sizeof(struct atm_qos));
1152 	msg_to_mpoad(msg, client);
1153 }
1154 
1155 static void MPOA_res_reply_rcvd(struct k_message *msg, struct mpoa_client *mpc)
1156 {
1157 	__be32 dst_ip = msg->content.in_info.in_dst_ip;
1158 	in_cache_entry *entry = mpc->in_ops->get(dst_ip, mpc);
1159 
1160 	dprintk("(%s) ip %pI4\n",
1161 		mpc->dev->name, &dst_ip);
1162 	ddprintk("(%s) entry = %p",
1163 		 mpc->dev->name, entry);
1164 	if (entry == NULL) {
1165 		pr_info("(%s) ARGH, received res. reply for an entry that doesn't exist.\n",
1166 			mpc->dev->name);
1167 		return;
1168 	}
1169 	ddprintk_cont(" entry_state = %d ", entry->entry_state);
1170 
1171 	if (entry->entry_state == INGRESS_RESOLVED) {
1172 		pr_info("(%s) RESOLVED entry!\n", mpc->dev->name);
1173 		mpc->in_ops->put(entry);
1174 		return;
1175 	}
1176 
1177 	entry->ctrl_info = msg->content.in_info;
1178 	entry->time = ktime_get_seconds();
1179 	/* Used in refreshing func from now on */
1180 	entry->reply_wait = ktime_get_seconds();
1181 	entry->refresh_time = 0;
1182 	ddprintk_cont("entry->shortcut = %p\n", entry->shortcut);
1183 
1184 	if (entry->entry_state == INGRESS_RESOLVING &&
1185 	    entry->shortcut != NULL) {
1186 		entry->entry_state = INGRESS_RESOLVED;
1187 		mpc->in_ops->put(entry);
1188 		return; /* Shortcut already open... */
1189 	}
1190 
1191 	if (entry->shortcut != NULL) {
1192 		pr_info("(%s) entry->shortcut != NULL, impossible!\n",
1193 			mpc->dev->name);
1194 		mpc->in_ops->put(entry);
1195 		return;
1196 	}
1197 
1198 	check_qos_and_open_shortcut(msg, mpc, entry);
1199 	entry->entry_state = INGRESS_RESOLVED;
1200 	mpc->in_ops->put(entry);
1201 
1202 	return;
1203 
1204 }
1205 
1206 static void ingress_purge_rcvd(struct k_message *msg, struct mpoa_client *mpc)
1207 {
1208 	__be32 dst_ip = msg->content.in_info.in_dst_ip;
1209 	__be32 mask = msg->ip_mask;
1210 	in_cache_entry *entry = mpc->in_ops->get_with_mask(dst_ip, mpc, mask);
1211 
1212 	if (entry == NULL) {
1213 		pr_info("(%s) purge for a non-existing entry, ip = %pI4\n",
1214 			mpc->dev->name, &dst_ip);
1215 		return;
1216 	}
1217 
1218 	do {
1219 		dprintk("(%s) removing an ingress entry, ip = %pI4\n",
1220 			mpc->dev->name, &dst_ip);
1221 		write_lock_bh(&mpc->ingress_lock);
1222 		mpc->in_ops->remove_entry(entry, mpc);
1223 		write_unlock_bh(&mpc->ingress_lock);
1224 		mpc->in_ops->put(entry);
1225 		entry = mpc->in_ops->get_with_mask(dst_ip, mpc, mask);
1226 	} while (entry != NULL);
1227 }
1228 
1229 static void egress_purge_rcvd(struct k_message *msg, struct mpoa_client *mpc)
1230 {
1231 	__be32 cache_id = msg->content.eg_info.cache_id;
1232 	eg_cache_entry *entry = mpc->eg_ops->get_by_cache_id(cache_id, mpc);
1233 
1234 	if (entry == NULL) {
1235 		dprintk("(%s) purge for a non-existing entry\n",
1236 			mpc->dev->name);
1237 		return;
1238 	}
1239 
1240 	write_lock_irq(&mpc->egress_lock);
1241 	mpc->eg_ops->remove_entry(entry, mpc);
1242 	write_unlock_irq(&mpc->egress_lock);
1243 
1244 	mpc->eg_ops->put(entry);
1245 }
1246 
1247 static void purge_egress_shortcut(struct atm_vcc *vcc, eg_cache_entry *entry)
1248 {
1249 	struct sock *sk;
1250 	struct k_message *purge_msg;
1251 	struct sk_buff *skb;
1252 
1253 	dprintk("entering\n");
1254 	if (vcc == NULL) {
1255 		pr_info("vcc == NULL\n");
1256 		return;
1257 	}
1258 
1259 	skb = alloc_skb(sizeof(struct k_message), GFP_ATOMIC);
1260 	if (skb == NULL) {
1261 		pr_info("out of memory\n");
1262 		return;
1263 	}
1264 
1265 	skb_put(skb, sizeof(struct k_message));
1266 	memset(skb->data, 0, sizeof(struct k_message));
1267 	purge_msg = (struct k_message *)skb->data;
1268 	purge_msg->type = DATA_PLANE_PURGE;
1269 	if (entry != NULL)
1270 		purge_msg->content.eg_info = entry->ctrl_info;
1271 
1272 	atm_force_charge(vcc, skb->truesize);
1273 
1274 	sk = sk_atm(vcc);
1275 	skb_queue_tail(&sk->sk_receive_queue, skb);
1276 	sk->sk_data_ready(sk);
1277 	dprintk("exiting\n");
1278 }
1279 
1280 /*
1281  * Our MPS died. Tell our daemon to send NHRP data plane purge to each
1282  * of the egress shortcuts we have.
1283  */
1284 static void mps_death(struct k_message *msg, struct mpoa_client *mpc)
1285 {
1286 	eg_cache_entry *entry;
1287 
1288 	dprintk("(%s)\n", mpc->dev->name);
1289 
1290 	if (memcmp(msg->MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN)) {
1291 		pr_info("(%s) wrong MPS\n", mpc->dev->name);
1292 		return;
1293 	}
1294 
1295 	/* FIXME: This knows too much of the cache structure */
1296 	read_lock_irq(&mpc->egress_lock);
1297 	entry = mpc->eg_cache;
1298 	while (entry != NULL) {
1299 		purge_egress_shortcut(entry->shortcut, entry);
1300 		entry = entry->next;
1301 	}
1302 	read_unlock_irq(&mpc->egress_lock);
1303 
1304 	mpc->in_ops->destroy_cache(mpc);
1305 	mpc->eg_ops->destroy_cache(mpc);
1306 }
1307 
1308 static void MPOA_cache_impos_rcvd(struct k_message *msg,
1309 				  struct mpoa_client *mpc)
1310 {
1311 	uint16_t holding_time;
1312 	eg_cache_entry *entry = mpc->eg_ops->get_by_cache_id(msg->content.eg_info.cache_id, mpc);
1313 
1314 	holding_time = msg->content.eg_info.holding_time;
1315 	dprintk("(%s) entry = %p, holding_time = %u\n",
1316 		mpc->dev->name, entry, holding_time);
1317 	if (entry == NULL && holding_time) {
1318 		entry = mpc->eg_ops->add_entry(msg, mpc);
1319 		mpc->eg_ops->put(entry);
1320 		return;
1321 	}
1322 	if (holding_time) {
1323 		mpc->eg_ops->update(entry, holding_time);
1324 		return;
1325 	}
1326 
1327 	write_lock_irq(&mpc->egress_lock);
1328 	mpc->eg_ops->remove_entry(entry, mpc);
1329 	write_unlock_irq(&mpc->egress_lock);
1330 
1331 	mpc->eg_ops->put(entry);
1332 }
1333 
1334 static void set_mpc_ctrl_addr_rcvd(struct k_message *mesg,
1335 				   struct mpoa_client *mpc)
1336 {
1337 	struct lec_priv *priv;
1338 	int i, retval ;
1339 
1340 	uint8_t tlv[4 + 1 + 1 + 1 + ATM_ESA_LEN];
1341 
1342 	tlv[0] = 00; tlv[1] = 0xa0; tlv[2] = 0x3e; tlv[3] = 0x2a; /* type  */
1343 	tlv[4] = 1 + 1 + ATM_ESA_LEN;  /* length                           */
1344 	tlv[5] = 0x02;                 /* MPOA client                      */
1345 	tlv[6] = 0x00;                 /* number of MPS MAC addresses      */
1346 
1347 	memcpy(&tlv[7], mesg->MPS_ctrl, ATM_ESA_LEN); /* MPC ctrl ATM addr */
1348 	memcpy(mpc->our_ctrl_addr, mesg->MPS_ctrl, ATM_ESA_LEN);
1349 
1350 	dprintk("(%s) setting MPC ctrl ATM address to",
1351 		mpc->dev ? mpc->dev->name : "<unknown>");
1352 	for (i = 7; i < sizeof(tlv); i++)
1353 		dprintk_cont(" %02x", tlv[i]);
1354 	dprintk_cont("\n");
1355 
1356 	if (mpc->dev) {
1357 		priv = netdev_priv(mpc->dev);
1358 		retval = priv->lane2_ops->associate_req(mpc->dev,
1359 							mpc->dev->dev_addr,
1360 							tlv, sizeof(tlv));
1361 		if (retval == 0)
1362 			pr_info("(%s) MPOA device type TLV association failed\n",
1363 				mpc->dev->name);
1364 		retval = priv->lane2_ops->resolve(mpc->dev, NULL, 1, NULL, NULL);
1365 		if (retval < 0)
1366 			pr_info("(%s) targetless LE_ARP request failed\n",
1367 				mpc->dev->name);
1368 	}
1369 }
1370 
1371 static void set_mps_mac_addr_rcvd(struct k_message *msg,
1372 				  struct mpoa_client *client)
1373 {
1374 
1375 	if (client->number_of_mps_macs)
1376 		kfree(client->mps_macs);
1377 	client->number_of_mps_macs = 0;
1378 	client->mps_macs = kmemdup(msg->MPS_ctrl, ETH_ALEN, GFP_KERNEL);
1379 	if (client->mps_macs == NULL) {
1380 		pr_info("out of memory\n");
1381 		return;
1382 	}
1383 	client->number_of_mps_macs = 1;
1384 }
1385 
1386 /*
1387  * purge egress cache and tell daemon to 'action' (DIE, RELOAD)
1388  */
1389 static void clean_up(struct k_message *msg, struct mpoa_client *mpc, int action)
1390 {
1391 
1392 	eg_cache_entry *entry;
1393 	msg->type = SND_EGRESS_PURGE;
1394 
1395 
1396 	/* FIXME: This knows too much of the cache structure */
1397 	read_lock_irq(&mpc->egress_lock);
1398 	entry = mpc->eg_cache;
1399 	while (entry != NULL) {
1400 		msg->content.eg_info = entry->ctrl_info;
1401 		dprintk("cache_id %u\n", entry->ctrl_info.cache_id);
1402 		msg_to_mpoad(msg, mpc);
1403 		entry = entry->next;
1404 	}
1405 	read_unlock_irq(&mpc->egress_lock);
1406 
1407 	msg->type = action;
1408 	msg_to_mpoad(msg, mpc);
1409 }
1410 
1411 static unsigned long checking_time;
1412 
1413 static void mpc_timer_refresh(void)
1414 {
1415 	mpc_timer.expires = jiffies + (MPC_P2 * HZ);
1416 	checking_time = mpc_timer.expires;
1417 	add_timer(&mpc_timer);
1418 }
1419 
1420 static void mpc_cache_check(struct timer_list *unused)
1421 {
1422 	struct mpoa_client *mpc = mpcs;
1423 	static unsigned long previous_resolving_check_time;
1424 	static unsigned long previous_refresh_time;
1425 
1426 	while (mpc != NULL) {
1427 		mpc->in_ops->clear_count(mpc);
1428 		mpc->eg_ops->clear_expired(mpc);
1429 		if (checking_time - previous_resolving_check_time >
1430 		    mpc->parameters.mpc_p4 * HZ) {
1431 			mpc->in_ops->check_resolving(mpc);
1432 			previous_resolving_check_time = checking_time;
1433 		}
1434 		if (checking_time - previous_refresh_time >
1435 		    mpc->parameters.mpc_p5 * HZ) {
1436 			mpc->in_ops->refresh(mpc);
1437 			previous_refresh_time = checking_time;
1438 		}
1439 		mpc = mpc->next;
1440 	}
1441 	mpc_timer_refresh();
1442 }
1443 
1444 static int atm_mpoa_ioctl(struct socket *sock, unsigned int cmd,
1445 			  unsigned long arg)
1446 {
1447 	int err = 0;
1448 	struct atm_vcc *vcc = ATM_SD(sock);
1449 
1450 	if (cmd != ATMMPC_CTRL && cmd != ATMMPC_DATA)
1451 		return -ENOIOCTLCMD;
1452 
1453 	if (!capable(CAP_NET_ADMIN))
1454 		return -EPERM;
1455 
1456 	switch (cmd) {
1457 	case ATMMPC_CTRL:
1458 		err = atm_mpoa_mpoad_attach(vcc, (int)arg);
1459 		if (err >= 0)
1460 			sock->state = SS_CONNECTED;
1461 		break;
1462 	case ATMMPC_DATA:
1463 		err = atm_mpoa_vcc_attach(vcc, (void __user *)arg);
1464 		break;
1465 	default:
1466 		break;
1467 	}
1468 	return err;
1469 }
1470 
1471 static struct atm_ioctl atm_ioctl_ops = {
1472 	.owner	= THIS_MODULE,
1473 	.ioctl	= atm_mpoa_ioctl,
1474 };
1475 
1476 static __init int atm_mpoa_init(void)
1477 {
1478 	register_atm_ioctl(&atm_ioctl_ops);
1479 
1480 	if (mpc_proc_init() != 0)
1481 		pr_info("failed to initialize /proc/mpoa\n");
1482 
1483 	pr_info("mpc.c: initialized\n");
1484 
1485 	return 0;
1486 }
1487 
1488 static void __exit atm_mpoa_cleanup(void)
1489 {
1490 	struct mpoa_client *mpc, *tmp;
1491 	struct atm_mpoa_qos *qos, *nextqos;
1492 	struct lec_priv *priv;
1493 
1494 	mpc_proc_clean();
1495 
1496 	del_timer_sync(&mpc_timer);
1497 	unregister_netdevice_notifier(&mpoa_notifier);
1498 	deregister_atm_ioctl(&atm_ioctl_ops);
1499 
1500 	mpc = mpcs;
1501 	mpcs = NULL;
1502 	while (mpc != NULL) {
1503 		tmp = mpc->next;
1504 		if (mpc->dev != NULL) {
1505 			stop_mpc(mpc);
1506 			priv = netdev_priv(mpc->dev);
1507 			if (priv->lane2_ops != NULL)
1508 				priv->lane2_ops->associate_indicator = NULL;
1509 		}
1510 		ddprintk("about to clear caches\n");
1511 		mpc->in_ops->destroy_cache(mpc);
1512 		mpc->eg_ops->destroy_cache(mpc);
1513 		ddprintk("caches cleared\n");
1514 		kfree(mpc->mps_macs);
1515 		memset(mpc, 0, sizeof(struct mpoa_client));
1516 		ddprintk("about to kfree %p\n", mpc);
1517 		kfree(mpc);
1518 		ddprintk("next mpc is at %p\n", tmp);
1519 		mpc = tmp;
1520 	}
1521 
1522 	qos = qos_head;
1523 	qos_head = NULL;
1524 	while (qos != NULL) {
1525 		nextqos = qos->next;
1526 		dprintk("freeing qos entry %p\n", qos);
1527 		kfree(qos);
1528 		qos = nextqos;
1529 	}
1530 }
1531 
1532 module_init(atm_mpoa_init);
1533 module_exit(atm_mpoa_cleanup);
1534 
1535 MODULE_DESCRIPTION("Multi-Protocol Over ATM (MPOA) driver");
1536 MODULE_LICENSE("GPL");
1537