xref: /linux/net/caif/cfcnfg.c (revision 3e4cd0737d2e9c3dd52153a23aef1753e3a99fc4)
1 /*
2  * Copyright (C) ST-Ericsson AB 2010
3  * Author:	Sjur Brendeland/sjur.brandeland@stericsson.com
4  * License terms: GNU General Public License (GPL) version 2
5  */
6 
7 #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
8 
9 #include <linux/kernel.h>
10 #include <linux/stddef.h>
11 #include <linux/slab.h>
12 #include <linux/netdevice.h>
13 #include <linux/module.h>
14 #include <net/caif/caif_layer.h>
15 #include <net/caif/cfpkt.h>
16 #include <net/caif/cfcnfg.h>
17 #include <net/caif/cfctrl.h>
18 #include <net/caif/cfmuxl.h>
19 #include <net/caif/cffrml.h>
20 #include <net/caif/cfserl.h>
21 #include <net/caif/cfsrvl.h>
22 #include <net/caif/caif_dev.h>
23 
24 #define container_obj(layr) container_of(layr, struct cfcnfg, layer)
25 
26 /* Information about CAIF physical interfaces held by Config Module in order
27  * to manage physical interfaces
28  */
29 struct cfcnfg_phyinfo {
30 	struct list_head node;
31 	bool up;
32 
33 	/* Pointer to the layer below the MUX (framing layer) */
34 	struct cflayer *frm_layer;
35 	/* Pointer to the lowest actual physical layer */
36 	struct cflayer *phy_layer;
37 	/* Unique identifier of the physical interface */
38 	unsigned int id;
39 	/* Preference of the physical in interface */
40 	enum cfcnfg_phy_preference pref;
41 
42 	/* Information about the physical device */
43 	struct dev_info dev_info;
44 
45 	/* Interface index */
46 	int ifindex;
47 
48 	/* Use Start of frame extension */
49 	bool use_stx;
50 
51 	/* Use Start of frame checksum */
52 	bool use_fcs;
53 };
54 
55 struct cfcnfg {
56 	struct cflayer layer;
57 	struct cflayer *ctrl;
58 	struct cflayer *mux;
59 	struct list_head phys;
60 	struct mutex lock;
61 };
62 
63 static void cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id,
64 			     enum cfctrl_srv serv, u8 phyid,
65 			     struct cflayer *adapt_layer);
66 static void cfcnfg_linkdestroy_rsp(struct cflayer *layer, u8 channel_id);
67 static void cfcnfg_reject_rsp(struct cflayer *layer, u8 channel_id,
68 			     struct cflayer *adapt_layer);
69 static void cfctrl_resp_func(void);
70 static void cfctrl_enum_resp(void);
71 
72 struct cfcnfg *cfcnfg_create(void)
73 {
74 	struct cfcnfg *this;
75 	struct cfctrl_rsp *resp;
76 
77 	might_sleep();
78 
79 	/* Initiate this layer */
80 	this = kzalloc(sizeof(struct cfcnfg), GFP_ATOMIC);
81 	if (!this) {
82 		pr_warn("Out of memory\n");
83 		return NULL;
84 	}
85 	this->mux = cfmuxl_create();
86 	if (!this->mux)
87 		goto out_of_mem;
88 	this->ctrl = cfctrl_create();
89 	if (!this->ctrl)
90 		goto out_of_mem;
91 	/* Initiate response functions */
92 	resp = cfctrl_get_respfuncs(this->ctrl);
93 	resp->enum_rsp = cfctrl_enum_resp;
94 	resp->linkerror_ind = cfctrl_resp_func;
95 	resp->linkdestroy_rsp = cfcnfg_linkdestroy_rsp;
96 	resp->sleep_rsp = cfctrl_resp_func;
97 	resp->wake_rsp = cfctrl_resp_func;
98 	resp->restart_rsp = cfctrl_resp_func;
99 	resp->radioset_rsp = cfctrl_resp_func;
100 	resp->linksetup_rsp = cfcnfg_linkup_rsp;
101 	resp->reject_rsp = cfcnfg_reject_rsp;
102 	INIT_LIST_HEAD(&this->phys);
103 
104 	cfmuxl_set_uplayer(this->mux, this->ctrl, 0);
105 	layer_set_dn(this->ctrl, this->mux);
106 	layer_set_up(this->ctrl, this);
107 	mutex_init(&this->lock);
108 
109 	return this;
110 out_of_mem:
111 	pr_warn("Out of memory\n");
112 
113 	synchronize_rcu();
114 
115 	kfree(this->mux);
116 	kfree(this->ctrl);
117 	kfree(this);
118 	return NULL;
119 }
120 
121 void cfcnfg_remove(struct cfcnfg *cfg)
122 {
123 	might_sleep();
124 	if (cfg) {
125 		synchronize_rcu();
126 
127 		kfree(cfg->mux);
128 		cfctrl_remove(cfg->ctrl);
129 		kfree(cfg);
130 	}
131 }
132 
133 static void cfctrl_resp_func(void)
134 {
135 }
136 
137 static struct cfcnfg_phyinfo *cfcnfg_get_phyinfo_rcu(struct cfcnfg *cnfg,
138 							u8 phyid)
139 {
140 	struct cfcnfg_phyinfo *phy;
141 
142 	list_for_each_entry_rcu(phy, &cnfg->phys, node)
143 		if (phy->id == phyid)
144 			return phy;
145 	return NULL;
146 }
147 
148 static void cfctrl_enum_resp(void)
149 {
150 }
151 
152 static struct dev_info *cfcnfg_get_phyid(struct cfcnfg *cnfg,
153 				  enum cfcnfg_phy_preference phy_pref)
154 {
155 	/* Try to match with specified preference */
156 	struct cfcnfg_phyinfo *phy;
157 
158 	list_for_each_entry_rcu(phy, &cnfg->phys, node) {
159 		if (phy->up && phy->pref == phy_pref &&
160 				phy->frm_layer != NULL)
161 
162 			return &phy->dev_info;
163 	}
164 
165 	/* Otherwise just return something */
166 	list_for_each_entry_rcu(phy, &cnfg->phys, node)
167 		if (phy->up)
168 			return &phy->dev_info;
169 
170 	return NULL;
171 }
172 
173 static int cfcnfg_get_id_from_ifi(struct cfcnfg *cnfg, int ifi)
174 {
175 	struct cfcnfg_phyinfo *phy;
176 
177 	list_for_each_entry_rcu(phy, &cnfg->phys, node)
178 		if (phy->ifindex == ifi && phy->up)
179 			return phy->id;
180 	return -ENODEV;
181 }
182 
183 int caif_disconnect_client(struct net *net, struct cflayer *adap_layer)
184 {
185 	u8 channel_id = 0;
186 	int ret = 0;
187 	struct cflayer *servl = NULL;
188 	struct cfcnfg *cfg = get_cfcnfg(net);
189 
190 	caif_assert(adap_layer != NULL);
191 
192 	channel_id = adap_layer->id;
193 	if (adap_layer->dn == NULL || channel_id == 0) {
194 		pr_err("adap_layer->dn == NULL or adap_layer->id is 0\n");
195 		ret = -ENOTCONN;
196 		goto end;
197 	}
198 
199 	servl = cfmuxl_remove_uplayer(cfg->mux, channel_id);
200 	if (servl == NULL) {
201 		pr_err("PROTOCOL ERROR - "
202 				"Error removing service_layer Channel_Id(%d)",
203 				channel_id);
204 		ret = -EINVAL;
205 		goto end;
206 	}
207 
208 	ret = cfctrl_linkdown_req(cfg->ctrl, channel_id, adap_layer);
209 
210 end:
211 	cfctrl_cancel_req(cfg->ctrl, adap_layer);
212 
213 	/* Do RCU sync before initiating cleanup */
214 	synchronize_rcu();
215 	if (adap_layer->ctrlcmd != NULL)
216 		adap_layer->ctrlcmd(adap_layer, CAIF_CTRLCMD_DEINIT_RSP, 0);
217 	return ret;
218 
219 }
220 EXPORT_SYMBOL(caif_disconnect_client);
221 
222 static void cfcnfg_linkdestroy_rsp(struct cflayer *layer, u8 channel_id)
223 {
224 }
225 
226 static const int protohead[CFCTRL_SRV_MASK] = {
227 	[CFCTRL_SRV_VEI] = 4,
228 	[CFCTRL_SRV_DATAGRAM] = 7,
229 	[CFCTRL_SRV_UTIL] = 4,
230 	[CFCTRL_SRV_RFM] = 3,
231 	[CFCTRL_SRV_DBG] = 3,
232 };
233 
234 
235 static int caif_connect_req_to_link_param(struct cfcnfg *cnfg,
236 				   struct caif_connect_request *s,
237 				   struct cfctrl_link_param *l)
238 {
239 	struct dev_info *dev_info;
240 	enum cfcnfg_phy_preference pref;
241 	int res;
242 
243 	memset(l, 0, sizeof(*l));
244 	/* In caif protocol low value is high priority */
245 	l->priority = CAIF_PRIO_MAX - s->priority + 1;
246 
247 	if (s->ifindex != 0) {
248 		res = cfcnfg_get_id_from_ifi(cnfg, s->ifindex);
249 		if (res < 0)
250 			return res;
251 		l->phyid = res;
252 	} else {
253 		switch (s->link_selector) {
254 		case CAIF_LINK_HIGH_BANDW:
255 			pref = CFPHYPREF_HIGH_BW;
256 			break;
257 		case CAIF_LINK_LOW_LATENCY:
258 			pref = CFPHYPREF_LOW_LAT;
259 			break;
260 		default:
261 			return -EINVAL;
262 		}
263 		dev_info = cfcnfg_get_phyid(cnfg, pref);
264 		if (dev_info == NULL)
265 			return -ENODEV;
266 		l->phyid = dev_info->id;
267 	}
268 	switch (s->protocol) {
269 	case CAIFPROTO_AT:
270 		l->linktype = CFCTRL_SRV_VEI;
271 		l->endpoint = (s->sockaddr.u.at.type >> 2) & 0x3;
272 		l->chtype = s->sockaddr.u.at.type & 0x3;
273 		break;
274 	case CAIFPROTO_DATAGRAM:
275 		l->linktype = CFCTRL_SRV_DATAGRAM;
276 		l->chtype = 0x00;
277 		l->u.datagram.connid = s->sockaddr.u.dgm.connection_id;
278 		break;
279 	case CAIFPROTO_DATAGRAM_LOOP:
280 		l->linktype = CFCTRL_SRV_DATAGRAM;
281 		l->chtype = 0x03;
282 		l->endpoint = 0x00;
283 		l->u.datagram.connid = s->sockaddr.u.dgm.connection_id;
284 		break;
285 	case CAIFPROTO_RFM:
286 		l->linktype = CFCTRL_SRV_RFM;
287 		l->u.datagram.connid = s->sockaddr.u.rfm.connection_id;
288 		strncpy(l->u.rfm.volume, s->sockaddr.u.rfm.volume,
289 			sizeof(l->u.rfm.volume)-1);
290 		l->u.rfm.volume[sizeof(l->u.rfm.volume)-1] = 0;
291 		break;
292 	case CAIFPROTO_UTIL:
293 		l->linktype = CFCTRL_SRV_UTIL;
294 		l->endpoint = 0x00;
295 		l->chtype = 0x00;
296 		strncpy(l->u.utility.name, s->sockaddr.u.util.service,
297 			sizeof(l->u.utility.name)-1);
298 		l->u.utility.name[sizeof(l->u.utility.name)-1] = 0;
299 		caif_assert(sizeof(l->u.utility.name) > 10);
300 		l->u.utility.paramlen = s->param.size;
301 		if (l->u.utility.paramlen > sizeof(l->u.utility.params))
302 			l->u.utility.paramlen = sizeof(l->u.utility.params);
303 
304 		memcpy(l->u.utility.params, s->param.data,
305 		       l->u.utility.paramlen);
306 
307 		break;
308 	case CAIFPROTO_DEBUG:
309 		l->linktype = CFCTRL_SRV_DBG;
310 		l->endpoint = s->sockaddr.u.dbg.service;
311 		l->chtype = s->sockaddr.u.dbg.type;
312 		break;
313 	default:
314 		return -EINVAL;
315 	}
316 	return 0;
317 }
318 
319 int caif_connect_client(struct net *net, struct caif_connect_request *conn_req,
320 			struct cflayer *adap_layer, int *ifindex,
321 				int *proto_head,
322 				int *proto_tail)
323 {
324 	struct cflayer *frml;
325 	struct cfcnfg_phyinfo *phy;
326 	int err;
327 	struct cfctrl_link_param param;
328 	struct cfcnfg *cfg = get_cfcnfg(net);
329 	caif_assert(cfg != NULL);
330 
331 	rcu_read_lock();
332 	err = caif_connect_req_to_link_param(cfg, conn_req, &param);
333 	if (err)
334 		goto unlock;
335 
336 	phy = cfcnfg_get_phyinfo_rcu(cfg, param.phyid);
337 	if (!phy) {
338 		err = -ENODEV;
339 		goto unlock;
340 	}
341 	err = -EINVAL;
342 
343 	if (adap_layer == NULL) {
344 		pr_err("adap_layer is zero\n");
345 		goto unlock;
346 	}
347 	if (adap_layer->receive == NULL) {
348 		pr_err("adap_layer->receive is NULL\n");
349 		goto unlock;
350 	}
351 	if (adap_layer->ctrlcmd == NULL) {
352 		pr_err("adap_layer->ctrlcmd == NULL\n");
353 		goto unlock;
354 	}
355 
356 	err = -ENODEV;
357 	frml = phy->frm_layer;
358 	if (frml == NULL) {
359 		pr_err("Specified PHY type does not exist!\n");
360 		goto unlock;
361 	}
362 	caif_assert(param.phyid == phy->id);
363 	caif_assert(phy->frm_layer->id ==
364 		     param.phyid);
365 	caif_assert(phy->phy_layer->id ==
366 		     param.phyid);
367 
368 	*ifindex = phy->ifindex;
369 	*proto_tail = 2;
370 	*proto_head =
371 
372 	protohead[param.linktype] + (phy->use_stx ? 1 : 0);
373 
374 	rcu_read_unlock();
375 
376 	/* FIXME: ENUMERATE INITIALLY WHEN ACTIVATING PHYSICAL INTERFACE */
377 	cfctrl_enum_req(cfg->ctrl, param.phyid);
378 	return cfctrl_linkup_request(cfg->ctrl, &param, adap_layer);
379 
380 unlock:
381 	rcu_read_unlock();
382 	return err;
383 }
384 EXPORT_SYMBOL(caif_connect_client);
385 
386 static void cfcnfg_reject_rsp(struct cflayer *layer, u8 channel_id,
387 			     struct cflayer *adapt_layer)
388 {
389 	if (adapt_layer != NULL && adapt_layer->ctrlcmd != NULL)
390 		adapt_layer->ctrlcmd(adapt_layer,
391 				     CAIF_CTRLCMD_INIT_FAIL_RSP, 0);
392 }
393 
394 static void
395 cfcnfg_linkup_rsp(struct cflayer *layer, u8 channel_id, enum cfctrl_srv serv,
396 		  u8 phyid, struct cflayer *adapt_layer)
397 {
398 	struct cfcnfg *cnfg = container_obj(layer);
399 	struct cflayer *servicel = NULL;
400 	struct cfcnfg_phyinfo *phyinfo;
401 	struct net_device *netdev;
402 
403 	rcu_read_lock();
404 
405 	if (adapt_layer == NULL) {
406 		pr_debug("link setup response but no client exist,"
407 				"send linkdown back\n");
408 		cfctrl_linkdown_req(cnfg->ctrl, channel_id, NULL);
409 		goto unlock;
410 	}
411 
412 	caif_assert(cnfg != NULL);
413 	caif_assert(phyid != 0);
414 
415 	phyinfo = cfcnfg_get_phyinfo_rcu(cnfg, phyid);
416 	if (phyinfo == NULL) {
417 		pr_err("ERROR: Link Layer Device dissapeared"
418 				"while connecting\n");
419 		goto unlock;
420 	}
421 
422 	caif_assert(phyinfo != NULL);
423 	caif_assert(phyinfo->id == phyid);
424 	caif_assert(phyinfo->phy_layer != NULL);
425 	caif_assert(phyinfo->phy_layer->id == phyid);
426 
427 	adapt_layer->id = channel_id;
428 
429 	switch (serv) {
430 	case CFCTRL_SRV_VEI:
431 		servicel = cfvei_create(channel_id, &phyinfo->dev_info);
432 		break;
433 	case CFCTRL_SRV_DATAGRAM:
434 		servicel = cfdgml_create(channel_id,
435 					&phyinfo->dev_info);
436 		break;
437 	case CFCTRL_SRV_RFM:
438 		netdev = phyinfo->dev_info.dev;
439 		servicel = cfrfml_create(channel_id, &phyinfo->dev_info,
440 						netdev->mtu);
441 		break;
442 	case CFCTRL_SRV_UTIL:
443 		servicel = cfutill_create(channel_id, &phyinfo->dev_info);
444 		break;
445 	case CFCTRL_SRV_VIDEO:
446 		servicel = cfvidl_create(channel_id, &phyinfo->dev_info);
447 		break;
448 	case CFCTRL_SRV_DBG:
449 		servicel = cfdbgl_create(channel_id, &phyinfo->dev_info);
450 		break;
451 	default:
452 		pr_err("Protocol error. Link setup response "
453 				"- unknown channel type\n");
454 		goto unlock;
455 	}
456 	if (!servicel) {
457 		pr_warn("Out of memory\n");
458 		goto unlock;
459 	}
460 	layer_set_dn(servicel, cnfg->mux);
461 	cfmuxl_set_uplayer(cnfg->mux, servicel, channel_id);
462 	layer_set_up(servicel, adapt_layer);
463 	layer_set_dn(adapt_layer, servicel);
464 
465 	rcu_read_unlock();
466 
467 	servicel->ctrlcmd(servicel, CAIF_CTRLCMD_INIT_RSP, 0);
468 	return;
469 unlock:
470 	rcu_read_unlock();
471 }
472 
473 void
474 cfcnfg_add_phy_layer(struct cfcnfg *cnfg, enum cfcnfg_phy_type phy_type,
475 		     struct net_device *dev, struct cflayer *phy_layer,
476 		     enum cfcnfg_phy_preference pref,
477 		     bool fcs, bool stx)
478 {
479 	struct cflayer *frml;
480 	struct cflayer *phy_driver = NULL;
481 	struct cfcnfg_phyinfo *phyinfo;
482 	int i;
483 	u8 phyid;
484 
485 	mutex_lock(&cnfg->lock);
486 
487 	/* CAIF protocol allow maximum 6 link-layers */
488 	for (i = 0; i < 7; i++) {
489 		phyid = (dev->ifindex + i) & 0x7;
490 		if (phyid == 0)
491 			continue;
492 		if (cfcnfg_get_phyinfo_rcu(cnfg, phyid) == NULL)
493 			goto got_phyid;
494 	}
495 	pr_warn("Too many CAIF Link Layers (max 6)\n");
496 	goto out;
497 
498 got_phyid:
499 	phyinfo = kzalloc(sizeof(struct cfcnfg_phyinfo), GFP_ATOMIC);
500 
501 	switch (phy_type) {
502 	case CFPHYTYPE_FRAG:
503 		phy_driver =
504 		    cfserl_create(CFPHYTYPE_FRAG, phyid, stx);
505 		if (!phy_driver) {
506 			pr_warn("Out of memory\n");
507 			goto out;
508 		}
509 		break;
510 	case CFPHYTYPE_CAIF:
511 		phy_driver = NULL;
512 		break;
513 	default:
514 		goto out;
515 	}
516 	phy_layer->id = phyid;
517 	phyinfo->pref = pref;
518 	phyinfo->id = phyid;
519 	phyinfo->dev_info.id = phyid;
520 	phyinfo->dev_info.dev = dev;
521 	phyinfo->phy_layer = phy_layer;
522 	phyinfo->ifindex = dev->ifindex;
523 	phyinfo->use_stx = stx;
524 	phyinfo->use_fcs = fcs;
525 
526 	phy_layer->type = phy_type;
527 	frml = cffrml_create(phyid, fcs);
528 
529 	if (!frml) {
530 		pr_warn("Out of memory\n");
531 		kfree(phyinfo);
532 		goto out;
533 	}
534 	phyinfo->frm_layer = frml;
535 	layer_set_up(frml, cnfg->mux);
536 
537 	if (phy_driver != NULL) {
538 		phy_driver->id = phyid;
539 		layer_set_dn(frml, phy_driver);
540 		layer_set_up(phy_driver, frml);
541 		layer_set_dn(phy_driver, phy_layer);
542 		layer_set_up(phy_layer, phy_driver);
543 	} else {
544 		layer_set_dn(frml, phy_layer);
545 		layer_set_up(phy_layer, frml);
546 	}
547 
548 	list_add_rcu(&phyinfo->node, &cnfg->phys);
549 out:
550 	mutex_unlock(&cnfg->lock);
551 }
552 EXPORT_SYMBOL(cfcnfg_add_phy_layer);
553 
554 int cfcnfg_set_phy_state(struct cfcnfg *cnfg, struct cflayer *phy_layer,
555 		bool up)
556 {
557 	struct cfcnfg_phyinfo *phyinfo;
558 
559 	rcu_read_lock();
560 	phyinfo = cfcnfg_get_phyinfo_rcu(cnfg, phy_layer->id);
561 	if (phyinfo == NULL) {
562 		rcu_read_unlock();
563 		return -ENODEV;
564 	}
565 
566 	if (phyinfo->up == up) {
567 		rcu_read_unlock();
568 		return 0;
569 	}
570 	phyinfo->up = up;
571 
572 	if (up) {
573 		cffrml_hold(phyinfo->frm_layer);
574 		cfmuxl_set_dnlayer(cnfg->mux, phyinfo->frm_layer,
575 					phy_layer->id);
576 	} else {
577 		cfmuxl_remove_dnlayer(cnfg->mux, phy_layer->id);
578 		cffrml_put(phyinfo->frm_layer);
579 	}
580 
581 	rcu_read_unlock();
582 	return 0;
583 }
584 EXPORT_SYMBOL(cfcnfg_set_phy_state);
585 
586 int cfcnfg_del_phy_layer(struct cfcnfg *cnfg, struct cflayer *phy_layer)
587 {
588 	struct cflayer *frml, *frml_dn;
589 	u16 phyid;
590 	struct cfcnfg_phyinfo *phyinfo;
591 
592 	might_sleep();
593 
594 	mutex_lock(&cnfg->lock);
595 
596 	phyid = phy_layer->id;
597 	phyinfo = cfcnfg_get_phyinfo_rcu(cnfg, phyid);
598 
599 	if (phyinfo == NULL) {
600 		mutex_unlock(&cnfg->lock);
601 		return 0;
602 	}
603 	caif_assert(phyid == phyinfo->id);
604 	caif_assert(phy_layer == phyinfo->phy_layer);
605 	caif_assert(phy_layer->id == phyid);
606 	caif_assert(phyinfo->frm_layer->id == phyid);
607 
608 	list_del_rcu(&phyinfo->node);
609 	synchronize_rcu();
610 
611 	/* Fail if reference count is not zero */
612 	if (cffrml_refcnt_read(phyinfo->frm_layer) != 0) {
613 		pr_info("Wait for device inuse\n");
614 		list_add_rcu(&phyinfo->node, &cnfg->phys);
615 		mutex_unlock(&cnfg->lock);
616 		return -EAGAIN;
617 	}
618 
619 	frml = phyinfo->frm_layer;
620 	frml_dn = frml->dn;
621 	cffrml_set_uplayer(frml, NULL);
622 	cffrml_set_dnlayer(frml, NULL);
623 	if (phy_layer != frml_dn) {
624 		layer_set_up(frml_dn, NULL);
625 		layer_set_dn(frml_dn, NULL);
626 	}
627 	layer_set_up(phy_layer, NULL);
628 
629 	if (phyinfo->phy_layer != frml_dn)
630 		kfree(frml_dn);
631 
632 	cffrml_free(frml);
633 	kfree(phyinfo);
634 	mutex_unlock(&cnfg->lock);
635 
636 	return 0;
637 }
638 EXPORT_SYMBOL(cfcnfg_del_phy_layer);
639