net: Add a flow_cache_flush_deferred function
[linux-2.6.git] / net / caif / cfctrl.c
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