xref: /openbmc/linux/net/caif/cfctrl.c (revision 54525552) 
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/stddef.h>
10 #include <linux/spinlock.h>
11 #include <linux/slab.h>
12 #include <net/caif/caif_layer.h>
13 #include <net/caif/cfpkt.h>
14 #include <net/caif/cfctrl.h>
15 
16 #define container_obj(layr) container_of(layr, struct cfctrl, serv.layer)
17 #define UTILITY_NAME_LENGTH 16
18 #define CFPKT_CTRL_PKT_LEN 20
19 
20 #ifdef CAIF_NO_LOOP
21 static int handle_loop(struct cfctrl *ctrl,
22 			      int cmd, struct cfpkt *pkt){
23 	return -1;
24 }
25 #else
26 static int handle_loop(struct cfctrl *ctrl,
27 		int cmd, struct cfpkt *pkt);
28 #endif
29 static int cfctrl_recv(struct cflayer *layr, struct cfpkt *pkt);
30 static void cfctrl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
31 			   int phyid);
32 
33 
34 struct cflayer *cfctrl_create(void)
35 {
36 	struct dev_info dev_info;
37 	struct cfctrl *this =
38 		kmalloc(sizeof(struct cfctrl), GFP_ATOMIC);
39 	if (!this) {
40 		pr_warn("Out of memory\n");
41 		return NULL;
42 	}
43 	caif_assert(offsetof(struct cfctrl, serv.layer) == 0);
44 	memset(&dev_info, 0, sizeof(dev_info));
45 	dev_info.id = 0xff;
46 	memset(this, 0, sizeof(*this));
47 	cfsrvl_init(&this->serv, 0, &dev_info, false);
48 	atomic_set(&this->req_seq_no, 1);
49 	atomic_set(&this->rsp_seq_no, 1);
50 	this->serv.layer.receive = cfctrl_recv;
51 	sprintf(this->serv.layer.name, "ctrl");
52 	this->serv.layer.ctrlcmd = cfctrl_ctrlcmd;
53 #ifndef CAIF_NO_LOOP
54 	spin_lock_init(&this->loop_linkid_lock);
55 	this->loop_linkid = 1;
56 #endif
57 	spin_lock_init(&this->info_list_lock);
58 	INIT_LIST_HEAD(&this->list);
59 	return &this->serv.layer;
60 }
61 
62 void cfctrl_remove(struct cflayer *layer)
63 {
64 	struct cfctrl_request_info *p, *tmp;
65 	struct cfctrl *ctrl = container_obj(layer);
66 
67 	spin_lock_bh(&ctrl->info_list_lock);
68 	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
69 		list_del(&p->list);
70 		kfree(p);
71 	}
72 	spin_unlock_bh(&ctrl->info_list_lock);
73 	kfree(layer);
74 }
75 
76 static bool param_eq(const struct cfctrl_link_param *p1,
77 			const struct cfctrl_link_param *p2)
78 {
79 	bool eq =
80 	    p1->linktype == p2->linktype &&
81 	    p1->priority == p2->priority &&
82 	    p1->phyid == p2->phyid &&
83 	    p1->endpoint == p2->endpoint && p1->chtype == p2->chtype;
84 
85 	if (!eq)
86 		return false;
87 
88 	switch (p1->linktype) {
89 	case CFCTRL_SRV_VEI:
90 		return true;
91 	case CFCTRL_SRV_DATAGRAM:
92 		return p1->u.datagram.connid == p2->u.datagram.connid;
93 	case CFCTRL_SRV_RFM:
94 		return
95 		    p1->u.rfm.connid == p2->u.rfm.connid &&
96 		    strcmp(p1->u.rfm.volume, p2->u.rfm.volume) == 0;
97 	case CFCTRL_SRV_UTIL:
98 		return
99 		    p1->u.utility.fifosize_kb == p2->u.utility.fifosize_kb
100 		    && p1->u.utility.fifosize_bufs ==
101 		    p2->u.utility.fifosize_bufs
102 		    && strcmp(p1->u.utility.name, p2->u.utility.name) == 0
103 		    && p1->u.utility.paramlen == p2->u.utility.paramlen
104 		    && memcmp(p1->u.utility.params, p2->u.utility.params,
105 			      p1->u.utility.paramlen) == 0;
106 
107 	case CFCTRL_SRV_VIDEO:
108 		return p1->u.video.connid == p2->u.video.connid;
109 	case CFCTRL_SRV_DBG:
110 		return true;
111 	case CFCTRL_SRV_DECM:
112 		return false;
113 	default:
114 		return false;
115 	}
116 	return false;
117 }
118 
119 static bool cfctrl_req_eq(const struct cfctrl_request_info *r1,
120 			  const struct cfctrl_request_info *r2)
121 {
122 	if (r1->cmd != r2->cmd)
123 		return false;
124 	if (r1->cmd == CFCTRL_CMD_LINK_SETUP)
125 		return param_eq(&r1->param, &r2->param);
126 	else
127 		return r1->channel_id == r2->channel_id;
128 }
129 
130 /* Insert request at the end */
131 static void cfctrl_insert_req(struct cfctrl *ctrl,
132 			      struct cfctrl_request_info *req)
133 {
134 	spin_lock_bh(&ctrl->info_list_lock);
135 	atomic_inc(&ctrl->req_seq_no);
136 	req->sequence_no = atomic_read(&ctrl->req_seq_no);
137 	list_add_tail(&req->list, &ctrl->list);
138 	spin_unlock_bh(&ctrl->info_list_lock);
139 }
140 
141 /* Compare and remove request */
142 static struct cfctrl_request_info *cfctrl_remove_req(struct cfctrl *ctrl,
143 						struct cfctrl_request_info *req)
144 {
145 	struct cfctrl_request_info *p, *tmp, *first;
146 
147 	first = list_first_entry(&ctrl->list, struct cfctrl_request_info, list);
148 
149 	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
150 		if (cfctrl_req_eq(req, p)) {
151 			if (p != first)
152 				pr_warn("Requests are not received in order\n");
153 
154 			atomic_set(&ctrl->rsp_seq_no,
155 					 p->sequence_no);
156 			list_del(&p->list);
157 			goto out;
158 		}
159 	}
160 	p = NULL;
161 out:
162 	return p;
163 }
164 
165 struct cfctrl_rsp *cfctrl_get_respfuncs(struct cflayer *layer)
166 {
167 	struct cfctrl *this = container_obj(layer);
168 	return &this->res;
169 }
170 
171 static void init_info(struct caif_payload_info *info, struct cfctrl *cfctrl)
172 {
173 	info->hdr_len = 0;
174 	info->channel_id = cfctrl->serv.layer.id;
175 	info->dev_info = &cfctrl->serv.dev_info;
176 }
177 
178 void cfctrl_enum_req(struct cflayer *layer, u8 physlinkid)
179 {
180 	struct cfctrl *cfctrl = container_obj(layer);
181 	struct cfpkt *pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
182 	struct cflayer *dn = cfctrl->serv.layer.dn;
183 	if (!pkt) {
184 		pr_warn("Out of memory\n");
185 		return;
186 	}
187 	if (!dn) {
188 		pr_debug("not able to send enum request\n");
189 		return;
190 	}
191 	caif_assert(offsetof(struct cfctrl, serv.layer) == 0);
192 	init_info(cfpkt_info(pkt), cfctrl);
193 	cfpkt_info(pkt)->dev_info->id = physlinkid;
194 	cfctrl->serv.dev_info.id = physlinkid;
195 	cfpkt_addbdy(pkt, CFCTRL_CMD_ENUM);
196 	cfpkt_addbdy(pkt, physlinkid);
197 	dn->transmit(dn, pkt);
198 }
199 
200 int cfctrl_linkup_request(struct cflayer *layer,
201 			   struct cfctrl_link_param *param,
202 			   struct cflayer *user_layer)
203 {
204 	struct cfctrl *cfctrl = container_obj(layer);
205 	u32 tmp32;
206 	u16 tmp16;
207 	u8 tmp8;
208 	struct cfctrl_request_info *req;
209 	int ret;
210 	char utility_name[16];
211 	struct cfpkt *pkt;
212 	struct cflayer *dn = cfctrl->serv.layer.dn;
213 
214 	if (!dn) {
215 		pr_debug("not able to send linkup request\n");
216 		return -ENODEV;
217 	}
218 
219 	if (cfctrl_cancel_req(layer, user_layer) > 0) {
220 		/* Slight Paranoia, check if already connecting */
221 		pr_err("Duplicate connect request for same client\n");
222 		WARN_ON(1);
223 		return -EALREADY;
224 	}
225 
226 	pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
227 	if (!pkt) {
228 		pr_warn("Out of memory\n");
229 		return -ENOMEM;
230 	}
231 	cfpkt_addbdy(pkt, CFCTRL_CMD_LINK_SETUP);
232 	cfpkt_addbdy(pkt, (param->chtype << 4) | param->linktype);
233 	cfpkt_addbdy(pkt, (param->priority << 3) | param->phyid);
234 	cfpkt_addbdy(pkt, param->endpoint & 0x03);
235 
236 	switch (param->linktype) {
237 	case CFCTRL_SRV_VEI:
238 		break;
239 	case CFCTRL_SRV_VIDEO:
240 		cfpkt_addbdy(pkt, (u8) param->u.video.connid);
241 		break;
242 	case CFCTRL_SRV_DBG:
243 		break;
244 	case CFCTRL_SRV_DATAGRAM:
245 		tmp32 = cpu_to_le32(param->u.datagram.connid);
246 		cfpkt_add_body(pkt, &tmp32, 4);
247 		break;
248 	case CFCTRL_SRV_RFM:
249 		/* Construct a frame, convert DatagramConnectionID to network
250 		 * format long and copy it out...
251 		 */
252 		tmp32 = cpu_to_le32(param->u.rfm.connid);
253 		cfpkt_add_body(pkt, &tmp32, 4);
254 		/* Add volume name, including zero termination... */
255 		cfpkt_add_body(pkt, param->u.rfm.volume,
256 			       strlen(param->u.rfm.volume) + 1);
257 		break;
258 	case CFCTRL_SRV_UTIL:
259 		tmp16 = cpu_to_le16(param->u.utility.fifosize_kb);
260 		cfpkt_add_body(pkt, &tmp16, 2);
261 		tmp16 = cpu_to_le16(param->u.utility.fifosize_bufs);
262 		cfpkt_add_body(pkt, &tmp16, 2);
263 		memset(utility_name, 0, sizeof(utility_name));
264 		strncpy(utility_name, param->u.utility.name,
265 			UTILITY_NAME_LENGTH - 1);
266 		cfpkt_add_body(pkt, utility_name, UTILITY_NAME_LENGTH);
267 		tmp8 = param->u.utility.paramlen;
268 		cfpkt_add_body(pkt, &tmp8, 1);
269 		cfpkt_add_body(pkt, param->u.utility.params,
270 			       param->u.utility.paramlen);
271 		break;
272 	default:
273 		pr_warn("Request setup of bad link type = %d\n",
274 			param->linktype);
275 		return -EINVAL;
276 	}
277 	req = kzalloc(sizeof(*req), GFP_KERNEL);
278 	if (!req) {
279 		pr_warn("Out of memory\n");
280 		return -ENOMEM;
281 	}
282 	req->client_layer = user_layer;
283 	req->cmd = CFCTRL_CMD_LINK_SETUP;
284 	req->param = *param;
285 	cfctrl_insert_req(cfctrl, req);
286 	init_info(cfpkt_info(pkt), cfctrl);
287 	/*
288 	 * NOTE:Always send linkup and linkdown request on the same
289 	 *	device as the payload. Otherwise old queued up payload
290 	 *	might arrive with the newly allocated channel ID.
291 	 */
292 	cfpkt_info(pkt)->dev_info->id = param->phyid;
293 	ret =
294 	    dn->transmit(dn, pkt);
295 	if (ret < 0) {
296 		int count;
297 
298 		count = cfctrl_cancel_req(&cfctrl->serv.layer,
299 						user_layer);
300 		if (count != 1)
301 			pr_err("Could not remove request (%d)", count);
302 			return -ENODEV;
303 	}
304 	return 0;
305 }
306 
307 int cfctrl_linkdown_req(struct cflayer *layer, u8 channelid,
308 				struct cflayer *client)
309 {
310 	int ret;
311 	struct cfctrl *cfctrl = container_obj(layer);
312 	struct cfpkt *pkt = cfpkt_create(CFPKT_CTRL_PKT_LEN);
313 	struct cflayer *dn = cfctrl->serv.layer.dn;
314 
315 	if (!pkt) {
316 		pr_warn("Out of memory\n");
317 		return -ENOMEM;
318 	}
319 
320 	if (!dn) {
321 		pr_debug("not able to send link-down request\n");
322 		return -ENODEV;
323 	}
324 
325 	cfpkt_addbdy(pkt, CFCTRL_CMD_LINK_DESTROY);
326 	cfpkt_addbdy(pkt, channelid);
327 	init_info(cfpkt_info(pkt), cfctrl);
328 	ret =
329 	    dn->transmit(dn, pkt);
330 #ifndef CAIF_NO_LOOP
331 	cfctrl->loop_linkused[channelid] = 0;
332 #endif
333 	return ret;
334 }
335 
336 int cfctrl_cancel_req(struct cflayer *layr, struct cflayer *adap_layer)
337 {
338 	struct cfctrl_request_info *p, *tmp;
339 	struct cfctrl *ctrl = container_obj(layr);
340 	int found = 0;
341 	spin_lock_bh(&ctrl->info_list_lock);
342 
343 	list_for_each_entry_safe(p, tmp, &ctrl->list, list) {
344 		if (p->client_layer == adap_layer) {
345 			list_del(&p->list);
346 			kfree(p);
347 			found++;
348 		}
349 	}
350 
351 	spin_unlock_bh(&ctrl->info_list_lock);
352 	return found;
353 }
354 
355 static int cfctrl_recv(struct cflayer *layer, struct cfpkt *pkt)
356 {
357 	u8 cmdrsp;
358 	u8 cmd;
359 	int ret = -1;
360 	u16 tmp16;
361 	u8 len;
362 	u8 param[255];
363 	u8 linkid;
364 	struct cfctrl *cfctrl = container_obj(layer);
365 	struct cfctrl_request_info rsp, *req;
366 
367 
368 	cfpkt_extr_head(pkt, &cmdrsp, 1);
369 	cmd = cmdrsp & CFCTRL_CMD_MASK;
370 	if (cmd != CFCTRL_CMD_LINK_ERR
371 	    && CFCTRL_RSP_BIT != (CFCTRL_RSP_BIT & cmdrsp)
372 		&& CFCTRL_ERR_BIT != (CFCTRL_ERR_BIT & cmdrsp)) {
373 		if (handle_loop(cfctrl, cmd, pkt) != 0)
374 			cmdrsp |= CFCTRL_ERR_BIT;
375 	}
376 
377 	switch (cmd) {
378 	case CFCTRL_CMD_LINK_SETUP:
379 		{
380 			enum cfctrl_srv serv;
381 			enum cfctrl_srv servtype;
382 			u8 endpoint;
383 			u8 physlinkid;
384 			u8 prio;
385 			u8 tmp;
386 			u32 tmp32;
387 			u8 *cp;
388 			int i;
389 			struct cfctrl_link_param linkparam;
390 			memset(&linkparam, 0, sizeof(linkparam));
391 
392 			cfpkt_extr_head(pkt, &tmp, 1);
393 
394 			serv = tmp & CFCTRL_SRV_MASK;
395 			linkparam.linktype = serv;
396 
397 			servtype = tmp >> 4;
398 			linkparam.chtype = servtype;
399 
400 			cfpkt_extr_head(pkt, &tmp, 1);
401 			physlinkid = tmp & 0x07;
402 			prio = tmp >> 3;
403 
404 			linkparam.priority = prio;
405 			linkparam.phyid = physlinkid;
406 			cfpkt_extr_head(pkt, &endpoint, 1);
407 			linkparam.endpoint = endpoint & 0x03;
408 
409 			switch (serv) {
410 			case CFCTRL_SRV_VEI:
411 			case CFCTRL_SRV_DBG:
412 				if (CFCTRL_ERR_BIT & cmdrsp)
413 					break;
414 				/* Link ID */
415 				cfpkt_extr_head(pkt, &linkid, 1);
416 				break;
417 			case CFCTRL_SRV_VIDEO:
418 				cfpkt_extr_head(pkt, &tmp, 1);
419 				linkparam.u.video.connid = tmp;
420 				if (CFCTRL_ERR_BIT & cmdrsp)
421 					break;
422 				/* Link ID */
423 				cfpkt_extr_head(pkt, &linkid, 1);
424 				break;
425 
426 			case CFCTRL_SRV_DATAGRAM:
427 				cfpkt_extr_head(pkt, &tmp32, 4);
428 				linkparam.u.datagram.connid =
429 				    le32_to_cpu(tmp32);
430 				if (CFCTRL_ERR_BIT & cmdrsp)
431 					break;
432 				/* Link ID */
433 				cfpkt_extr_head(pkt, &linkid, 1);
434 				break;
435 			case CFCTRL_SRV_RFM:
436 				/* Construct a frame, convert
437 				 * DatagramConnectionID
438 				 * to network format long and copy it out...
439 				 */
440 				cfpkt_extr_head(pkt, &tmp32, 4);
441 				linkparam.u.rfm.connid =
442 				  le32_to_cpu(tmp32);
443 				cp = (u8 *) linkparam.u.rfm.volume;
444 				for (cfpkt_extr_head(pkt, &tmp, 1);
445 				     cfpkt_more(pkt) && tmp != '\0';
446 				     cfpkt_extr_head(pkt, &tmp, 1))
447 					*cp++ = tmp;
448 				*cp = '\0';
449 
450 				if (CFCTRL_ERR_BIT & cmdrsp)
451 					break;
452 				/* Link ID */
453 				cfpkt_extr_head(pkt, &linkid, 1);
454 
455 				break;
456 			case CFCTRL_SRV_UTIL:
457 				/* Construct a frame, convert
458 				 * DatagramConnectionID
459 				 * to network format long and copy it out...
460 				 */
461 				/* Fifosize KB */
462 				cfpkt_extr_head(pkt, &tmp16, 2);
463 				linkparam.u.utility.fifosize_kb =
464 				    le16_to_cpu(tmp16);
465 				/* Fifosize bufs */
466 				cfpkt_extr_head(pkt, &tmp16, 2);
467 				linkparam.u.utility.fifosize_bufs =
468 				    le16_to_cpu(tmp16);
469 				/* name */
470 				cp = (u8 *) linkparam.u.utility.name;
471 				caif_assert(sizeof(linkparam.u.utility.name)
472 					     >= UTILITY_NAME_LENGTH);
473 				for (i = 0;
474 				     i < UTILITY_NAME_LENGTH
475 				     && cfpkt_more(pkt); i++) {
476 					cfpkt_extr_head(pkt, &tmp, 1);
477 					*cp++ = tmp;
478 				}
479 				/* Length */
480 				cfpkt_extr_head(pkt, &len, 1);
481 				linkparam.u.utility.paramlen = len;
482 				/* Param Data */
483 				cp = linkparam.u.utility.params;
484 				while (cfpkt_more(pkt) && len--) {
485 					cfpkt_extr_head(pkt, &tmp, 1);
486 					*cp++ = tmp;
487 				}
488 				if (CFCTRL_ERR_BIT & cmdrsp)
489 					break;
490 				/* Link ID */
491 				cfpkt_extr_head(pkt, &linkid, 1);
492 				/* Length */
493 				cfpkt_extr_head(pkt, &len, 1);
494 				/* Param Data */
495 				cfpkt_extr_head(pkt, &param, len);
496 				break;
497 			default:
498 				pr_warn("Request setup, invalid type (%d)\n",
499 					serv);
500 				goto error;
501 			}
502 
503 			rsp.cmd = cmd;
504 			rsp.param = linkparam;
505 			spin_lock_bh(&cfctrl->info_list_lock);
506 			req = cfctrl_remove_req(cfctrl, &rsp);
507 
508 			if (CFCTRL_ERR_BIT == (CFCTRL_ERR_BIT & cmdrsp) ||
509 				cfpkt_erroneous(pkt)) {
510 				pr_err("Invalid O/E bit or parse error "
511 						"on CAIF control channel\n");
512 				cfctrl->res.reject_rsp(cfctrl->serv.layer.up,
513 						       0,
514 						       req ? req->client_layer
515 						       : NULL);
516 			} else {
517 				cfctrl->res.linksetup_rsp(cfctrl->serv.
518 							  layer.up, linkid,
519 							  serv, physlinkid,
520 							  req ? req->
521 							  client_layer : NULL);
522 			}
523 
524 			if (req != NULL)
525 				kfree(req);
526 
527 			spin_unlock_bh(&cfctrl->info_list_lock);
528 		}
529 		break;
530 	case CFCTRL_CMD_LINK_DESTROY:
531 		cfpkt_extr_head(pkt, &linkid, 1);
532 		cfctrl->res.linkdestroy_rsp(cfctrl->serv.layer.up, linkid);
533 		break;
534 	case CFCTRL_CMD_LINK_ERR:
535 		pr_err("Frame Error Indication received\n");
536 		cfctrl->res.linkerror_ind();
537 		break;
538 	case CFCTRL_CMD_ENUM:
539 		cfctrl->res.enum_rsp();
540 		break;
541 	case CFCTRL_CMD_SLEEP:
542 		cfctrl->res.sleep_rsp();
543 		break;
544 	case CFCTRL_CMD_WAKE:
545 		cfctrl->res.wake_rsp();
546 		break;
547 	case CFCTRL_CMD_LINK_RECONF:
548 		cfctrl->res.restart_rsp();
549 		break;
550 	case CFCTRL_CMD_RADIO_SET:
551 		cfctrl->res.radioset_rsp();
552 		break;
553 	default:
554 		pr_err("Unrecognized Control Frame\n");
555 		goto error;
556 		break;
557 	}
558 	ret = 0;
559 error:
560 	cfpkt_destroy(pkt);
561 	return ret;
562 }
563 
564 static void cfctrl_ctrlcmd(struct cflayer *layr, enum caif_ctrlcmd ctrl,
565 			int phyid)
566 {
567 	struct cfctrl *this = container_obj(layr);
568 	switch (ctrl) {
569 	case _CAIF_CTRLCMD_PHYIF_FLOW_OFF_IND:
570 	case CAIF_CTRLCMD_FLOW_OFF_IND:
571 		spin_lock_bh(&this->info_list_lock);
572 		if (!list_empty(&this->list))
573 			pr_debug("Received flow off in control layer\n");
574 		spin_unlock_bh(&this->info_list_lock);
575 		break;
576 	case _CAIF_CTRLCMD_PHYIF_DOWN_IND: {
577 		struct cfctrl_request_info *p, *tmp;
578 
579 		/* Find all connect request and report failure */
580 		spin_lock_bh(&this->info_list_lock);
581 		list_for_each_entry_safe(p, tmp, &this->list, list) {
582 			if (p->param.phyid == phyid) {
583 				list_del(&p->list);
584 				p->client_layer->ctrlcmd(p->client_layer,
585 						CAIF_CTRLCMD_INIT_FAIL_RSP,
586 						phyid);
587 				kfree(p);
588 			}
589 		}
590 		spin_unlock_bh(&this->info_list_lock);
591 		break;
592 	}
593 	default:
594 		break;
595 	}
596 }
597 
598 #ifndef CAIF_NO_LOOP
599 static int handle_loop(struct cfctrl *ctrl, int cmd, struct cfpkt *pkt)
600 {
601 	static int last_linkid;
602 	static int dec;
603 	u8 linkid, linktype, tmp;
604 	switch (cmd) {
605 	case CFCTRL_CMD_LINK_SETUP:
606 		spin_lock_bh(&ctrl->loop_linkid_lock);
607 		if (!dec) {
608 			for (linkid = last_linkid + 1; linkid < 254; linkid++)
609 				if (!ctrl->loop_linkused[linkid])
610 					goto found;
611 		}
612 		dec = 1;
613 		for (linkid = last_linkid - 1; linkid > 1; linkid--)
614 			if (!ctrl->loop_linkused[linkid])
615 				goto found;
616 		spin_unlock_bh(&ctrl->loop_linkid_lock);
617 		return -1;
618 found:
619 		if (linkid < 10)
620 			dec = 0;
621 
622 		if (!ctrl->loop_linkused[linkid])
623 			ctrl->loop_linkused[linkid] = 1;
624 
625 		last_linkid = linkid;
626 
627 		cfpkt_add_trail(pkt, &linkid, 1);
628 		spin_unlock_bh(&ctrl->loop_linkid_lock);
629 		cfpkt_peek_head(pkt, &linktype, 1);
630 		if (linktype ==  CFCTRL_SRV_UTIL) {
631 			tmp = 0x01;
632 			cfpkt_add_trail(pkt, &tmp, 1);
633 			cfpkt_add_trail(pkt, &tmp, 1);
634 		}
635 		break;
636 
637 	case CFCTRL_CMD_LINK_DESTROY:
638 		spin_lock_bh(&ctrl->loop_linkid_lock);
639 		cfpkt_peek_head(pkt, &linkid, 1);
640 		ctrl->loop_linkused[linkid] = 0;
641 		spin_unlock_bh(&ctrl->loop_linkid_lock);
642 		break;
643 	default:
644 		break;
645 	}
646 	return 0;
647 }
648 #endif
649