xref: /openbmc/linux/drivers/s390/net/ctcm_mpc.c (revision 9a29f5fc)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *	Copyright IBM Corp. 2004, 2007
4  *	Authors:	Belinda Thompson (belindat@us.ibm.com)
5  *			Andy Richter (richtera@us.ibm.com)
6  *			Peter Tiedemann (ptiedem@de.ibm.com)
7  */
8 
9 /*
10 	This module exports functions to be used by CCS:
11 	EXPORT_SYMBOL(ctc_mpc_alloc_channel);
12 	EXPORT_SYMBOL(ctc_mpc_establish_connectivity);
13 	EXPORT_SYMBOL(ctc_mpc_dealloc_ch);
14 	EXPORT_SYMBOL(ctc_mpc_flow_control);
15 */
16 
17 #undef DEBUG
18 #undef DEBUGDATA
19 #undef DEBUGCCW
20 
21 #define KMSG_COMPONENT "ctcm"
22 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
23 
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/kernel.h>
27 #include <linux/slab.h>
28 #include <linux/errno.h>
29 #include <linux/types.h>
30 #include <linux/interrupt.h>
31 #include <linux/timer.h>
32 #include <linux/sched.h>
33 
34 #include <linux/signal.h>
35 #include <linux/string.h>
36 #include <linux/proc_fs.h>
37 
38 #include <linux/ip.h>
39 #include <linux/if_arp.h>
40 #include <linux/tcp.h>
41 #include <linux/skbuff.h>
42 #include <linux/ctype.h>
43 #include <linux/netdevice.h>
44 #include <net/dst.h>
45 
46 #include <linux/io.h>		/* instead of <asm/io.h> ok ? */
47 #include <asm/ccwdev.h>
48 #include <asm/ccwgroup.h>
49 #include <linux/bitops.h>	/* instead of <asm/bitops.h> ok ? */
50 #include <linux/uaccess.h>	/* instead of <asm/uaccess.h> ok ? */
51 #include <linux/wait.h>
52 #include <linux/moduleparam.h>
53 #include <asm/idals.h>
54 
55 #include "ctcm_main.h"
56 #include "ctcm_mpc.h"
57 #include "ctcm_fsms.h"
58 
59 static const struct xid2 init_xid = {
60 	.xid2_type_id	=	XID_FM2,
61 	.xid2_len	=	0x45,
62 	.xid2_adj_id	=	0,
63 	.xid2_rlen	=	0x31,
64 	.xid2_resv1	=	0,
65 	.xid2_flag1	=	0,
66 	.xid2_fmtt	=	0,
67 	.xid2_flag4	=	0x80,
68 	.xid2_resv2	=	0,
69 	.xid2_tgnum	=	0,
70 	.xid2_sender_id	=	0,
71 	.xid2_flag2	=	0,
72 	.xid2_option	=	XID2_0,
73 	.xid2_resv3	=	"\x00",
74 	.xid2_resv4	=	0,
75 	.xid2_dlc_type	=	XID2_READ_SIDE,
76 	.xid2_resv5	=	0,
77 	.xid2_mpc_flag	=	0,
78 	.xid2_resv6	=	0,
79 	.xid2_buf_len	=	(MPC_BUFSIZE_DEFAULT - 35),
80 };
81 
82 static const struct th_header thnorm = {
83 	.th_seg		=	0x00,
84 	.th_ch_flag	=	TH_IS_XID,
85 	.th_blk_flag	=	TH_DATA_IS_XID,
86 	.th_is_xid	=	0x01,
87 	.th_seq_num	=	0x00000000,
88 };
89 
90 static const struct th_header thdummy = {
91 	.th_seg		=	0x00,
92 	.th_ch_flag	=	0x00,
93 	.th_blk_flag	=	TH_DATA_IS_XID,
94 	.th_is_xid	=	0x01,
95 	.th_seq_num	=	0x00000000,
96 };
97 
98 /*
99  * Definition of one MPC group
100  */
101 
102 /*
103  * Compatibility macros for busy handling
104  * of network devices.
105  */
106 
107 static void ctcmpc_unpack_skb(struct channel *ch, struct sk_buff *pskb);
108 
109 /*
110  * MPC Group state machine actions (static prototypes)
111  */
112 static void mpc_action_nop(fsm_instance *fsm, int event, void *arg);
113 static void mpc_action_go_ready(fsm_instance *fsm, int event, void *arg);
114 static void mpc_action_go_inop(fsm_instance *fi, int event, void *arg);
115 static void mpc_action_timeout(fsm_instance *fi, int event, void *arg);
116 static int  mpc_validate_xid(struct mpcg_info *mpcginfo);
117 static void mpc_action_yside_xid(fsm_instance *fsm, int event, void *arg);
118 static void mpc_action_doxid0(fsm_instance *fsm, int event, void *arg);
119 static void mpc_action_doxid7(fsm_instance *fsm, int event, void *arg);
120 static void mpc_action_xside_xid(fsm_instance *fsm, int event, void *arg);
121 static void mpc_action_rcvd_xid0(fsm_instance *fsm, int event, void *arg);
122 static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg);
123 
124 #ifdef DEBUGDATA
125 /*-------------------------------------------------------------------*
126 * Dump buffer format						     *
127 *								     *
128 *--------------------------------------------------------------------*/
129 void ctcmpc_dumpit(char *buf, int len)
130 {
131 	__u32	ct, sw, rm, dup;
132 	char	*ptr, *rptr;
133 	char	tbuf[82], tdup[82];
134 	char	addr[22];
135 	char	boff[12];
136 	char	bhex[82], duphex[82];
137 	char	basc[40];
138 
139 	sw  = 0;
140 	rptr = ptr = buf;
141 	rm  = 16;
142 	duphex[0] = 0x00;
143 	dup = 0;
144 
145 	for (ct = 0; ct < len; ct++, ptr++, rptr++) {
146 		if (sw == 0) {
147 			sprintf(addr, "%16.16llx", (__u64)rptr);
148 
149 			sprintf(boff, "%4.4X", (__u32)ct);
150 			bhex[0] = '\0';
151 			basc[0] = '\0';
152 		}
153 		if ((sw == 4) || (sw == 12))
154 			strcat(bhex, " ");
155 		if (sw == 8)
156 			strcat(bhex, "	");
157 
158 		sprintf(tbuf, "%2.2llX", (__u64)*ptr);
159 
160 		tbuf[2] = '\0';
161 		strcat(bhex, tbuf);
162 		if ((0 != isprint(*ptr)) && (*ptr >= 0x20))
163 			basc[sw] = *ptr;
164 		else
165 			basc[sw] = '.';
166 
167 		basc[sw+1] = '\0';
168 		sw++;
169 		rm--;
170 		if (sw != 16)
171 			continue;
172 		if ((strcmp(duphex, bhex)) != 0) {
173 			if (dup != 0) {
174 				sprintf(tdup,
175 					"Duplicate as above to %s", addr);
176 				ctcm_pr_debug("		       --- %s ---\n",
177 						tdup);
178 			}
179 			ctcm_pr_debug("   %s (+%s) : %s  [%s]\n",
180 					addr, boff, bhex, basc);
181 			dup = 0;
182 			strcpy(duphex, bhex);
183 		} else
184 			dup++;
185 
186 		sw = 0;
187 		rm = 16;
188 	}  /* endfor */
189 
190 	if (sw != 0) {
191 		for ( ; rm > 0; rm--, sw++) {
192 			if ((sw == 4) || (sw == 12))
193 				strcat(bhex, " ");
194 			if (sw == 8)
195 				strcat(bhex, "	");
196 			strcat(bhex, "	");
197 			strcat(basc, " ");
198 		}
199 		if (dup != 0) {
200 			sprintf(tdup, "Duplicate as above to %s", addr);
201 			ctcm_pr_debug("		       --- %s ---\n", tdup);
202 		}
203 		ctcm_pr_debug("   %s (+%s) : %s  [%s]\n",
204 					addr, boff, bhex, basc);
205 	} else {
206 		if (dup >= 1) {
207 			sprintf(tdup, "Duplicate as above to %s", addr);
208 			ctcm_pr_debug("		       --- %s ---\n", tdup);
209 		}
210 		if (dup != 0) {
211 			ctcm_pr_debug("   %s (+%s) : %s  [%s]\n",
212 				addr, boff, bhex, basc);
213 		}
214 	}
215 
216 	return;
217 
218 }   /*	 end of ctcmpc_dumpit  */
219 #endif
220 
221 #ifdef DEBUGDATA
222 /*
223  * Dump header and first 16 bytes of an sk_buff for debugging purposes.
224  *
225  * skb		The sk_buff to dump.
226  * offset	Offset relative to skb-data, where to start the dump.
227  */
228 void ctcmpc_dump_skb(struct sk_buff *skb, int offset)
229 {
230 	__u8 *p = skb->data;
231 	struct th_header *header;
232 	struct pdu *pheader;
233 	int bl = skb->len;
234 	int i;
235 
236 	if (p == NULL)
237 		return;
238 
239 	p += offset;
240 	header = (struct th_header *)p;
241 
242 	ctcm_pr_debug("dump:\n");
243 	ctcm_pr_debug("skb len=%d \n", skb->len);
244 	if (skb->len > 2) {
245 		switch (header->th_ch_flag) {
246 		case TH_HAS_PDU:
247 			break;
248 		case 0x00:
249 		case TH_IS_XID:
250 			if ((header->th_blk_flag == TH_DATA_IS_XID) &&
251 			   (header->th_is_xid == 0x01))
252 				goto dumpth;
253 		case TH_SWEEP_REQ:
254 				goto dumpth;
255 		case TH_SWEEP_RESP:
256 				goto dumpth;
257 		default:
258 			break;
259 		}
260 
261 		pheader = (struct pdu *)p;
262 		ctcm_pr_debug("pdu->offset: %d hex: %04x\n",
263 			       pheader->pdu_offset, pheader->pdu_offset);
264 		ctcm_pr_debug("pdu->flag  : %02x\n", pheader->pdu_flag);
265 		ctcm_pr_debug("pdu->proto : %02x\n", pheader->pdu_proto);
266 		ctcm_pr_debug("pdu->seq   : %02x\n", pheader->pdu_seq);
267 					goto dumpdata;
268 
269 dumpth:
270 		ctcm_pr_debug("th->seg     : %02x\n", header->th_seg);
271 		ctcm_pr_debug("th->ch      : %02x\n", header->th_ch_flag);
272 		ctcm_pr_debug("th->blk_flag: %02x\n", header->th_blk_flag);
273 		ctcm_pr_debug("th->type    : %s\n",
274 			       (header->th_is_xid) ? "DATA" : "XID");
275 		ctcm_pr_debug("th->seqnum  : %04x\n", header->th_seq_num);
276 
277 	}
278 dumpdata:
279 	if (bl > 32)
280 		bl = 32;
281 	ctcm_pr_debug("data: ");
282 	for (i = 0; i < bl; i++)
283 		ctcm_pr_debug("%02x%s", *p++, (i % 16) ? " " : "\n");
284 	ctcm_pr_debug("\n");
285 }
286 #endif
287 
288 static struct net_device *ctcmpc_get_dev(int port_num)
289 {
290 	char device[20];
291 	struct net_device *dev;
292 	struct ctcm_priv *priv;
293 
294 	sprintf(device, "%s%i", MPC_DEVICE_NAME, port_num);
295 
296 	dev = __dev_get_by_name(&init_net, device);
297 
298 	if (dev == NULL) {
299 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
300 			"%s: Device not found by name: %s",
301 					CTCM_FUNTAIL, device);
302 		return NULL;
303 	}
304 	priv = dev->ml_priv;
305 	if (priv == NULL) {
306 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
307 			"%s(%s): dev->ml_priv is NULL",
308 					CTCM_FUNTAIL, device);
309 		return NULL;
310 	}
311 	if (priv->mpcg == NULL) {
312 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
313 			"%s(%s): priv->mpcg is NULL",
314 					CTCM_FUNTAIL, device);
315 		return NULL;
316 	}
317 	return dev;
318 }
319 
320 /*
321  * ctc_mpc_alloc_channel
322  *	(exported interface)
323  *
324  * Device Initialization :
325  *	ACTPATH  driven IO operations
326  */
327 int ctc_mpc_alloc_channel(int port_num, void (*callback)(int, int))
328 {
329 	struct net_device *dev;
330 	struct mpc_group *grp;
331 	struct ctcm_priv *priv;
332 
333 	dev = ctcmpc_get_dev(port_num);
334 	if (dev == NULL)
335 		return 1;
336 	priv = dev->ml_priv;
337 	grp = priv->mpcg;
338 
339 	grp->allochanfunc = callback;
340 	grp->port_num = port_num;
341 	grp->port_persist = 1;
342 
343 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
344 			"%s(%s): state=%s",
345 			CTCM_FUNTAIL, dev->name, fsm_getstate_str(grp->fsm));
346 
347 	switch (fsm_getstate(grp->fsm)) {
348 	case MPCG_STATE_INOP:
349 		/* Group is in the process of terminating */
350 		grp->alloc_called = 1;
351 		break;
352 	case MPCG_STATE_RESET:
353 		/* MPC Group will transition to state		  */
354 		/* MPCG_STATE_XID2INITW iff the minimum number	  */
355 		/* of 1 read and 1 write channel have successfully*/
356 		/* activated					  */
357 		/*fsm_newstate(grp->fsm, MPCG_STATE_XID2INITW);*/
358 		if (callback)
359 			grp->send_qllc_disc = 1;
360 		fallthrough;
361 	case MPCG_STATE_XID0IOWAIT:
362 		fsm_deltimer(&grp->timer);
363 		grp->outstanding_xid2 = 0;
364 		grp->outstanding_xid7 = 0;
365 		grp->outstanding_xid7_p2 = 0;
366 		grp->saved_xid2 = NULL;
367 		if (callback)
368 			ctcm_open(dev);
369 		fsm_event(priv->fsm, DEV_EVENT_START, dev);
370 		break;
371 	case MPCG_STATE_READY:
372 		/* XID exchanges completed after PORT was activated */
373 		/* Link station already active			    */
374 		/* Maybe timing issue...retry callback		    */
375 		grp->allocchan_callback_retries++;
376 		if (grp->allocchan_callback_retries < 4) {
377 			if (grp->allochanfunc)
378 				grp->allochanfunc(grp->port_num,
379 						  grp->group_max_buflen);
380 		} else {
381 			/* there are problems...bail out	    */
382 			/* there may be a state mismatch so restart */
383 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
384 			grp->allocchan_callback_retries = 0;
385 		}
386 		break;
387 	}
388 
389 	return 0;
390 }
391 EXPORT_SYMBOL(ctc_mpc_alloc_channel);
392 
393 /*
394  * ctc_mpc_establish_connectivity
395  *	(exported interface)
396  */
397 void ctc_mpc_establish_connectivity(int port_num,
398 				void (*callback)(int, int, int))
399 {
400 	struct net_device *dev;
401 	struct mpc_group *grp;
402 	struct ctcm_priv *priv;
403 	struct channel *rch, *wch;
404 
405 	dev = ctcmpc_get_dev(port_num);
406 	if (dev == NULL)
407 		return;
408 	priv = dev->ml_priv;
409 	grp = priv->mpcg;
410 	rch = priv->channel[CTCM_READ];
411 	wch = priv->channel[CTCM_WRITE];
412 
413 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
414 			"%s(%s): state=%s",
415 			CTCM_FUNTAIL, dev->name, fsm_getstate_str(grp->fsm));
416 
417 	grp->estconnfunc = callback;
418 	grp->port_num = port_num;
419 
420 	switch (fsm_getstate(grp->fsm)) {
421 	case MPCG_STATE_READY:
422 		/* XID exchanges completed after PORT was activated */
423 		/* Link station already active			    */
424 		/* Maybe timing issue...retry callback		    */
425 		fsm_deltimer(&grp->timer);
426 		grp->estconn_callback_retries++;
427 		if (grp->estconn_callback_retries < 4) {
428 			if (grp->estconnfunc) {
429 				grp->estconnfunc(grp->port_num, 0,
430 						grp->group_max_buflen);
431 				grp->estconnfunc = NULL;
432 			}
433 		} else {
434 			/* there are problems...bail out	 */
435 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
436 			grp->estconn_callback_retries = 0;
437 		}
438 		break;
439 	case MPCG_STATE_INOP:
440 	case MPCG_STATE_RESET:
441 		/* MPC Group is not ready to start XID - min num of */
442 		/* 1 read and 1 write channel have not been acquired*/
443 
444 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
445 			"%s(%s): REJECTED - inactive channels",
446 					CTCM_FUNTAIL, dev->name);
447 		if (grp->estconnfunc) {
448 			grp->estconnfunc(grp->port_num, -1, 0);
449 			grp->estconnfunc = NULL;
450 		}
451 		break;
452 	case MPCG_STATE_XID2INITW:
453 		/* alloc channel was called but no XID exchange    */
454 		/* has occurred. initiate xside XID exchange	   */
455 		/* make sure yside XID0 processing has not started */
456 
457 		if ((fsm_getstate(rch->fsm) > CH_XID0_PENDING) ||
458 			(fsm_getstate(wch->fsm) > CH_XID0_PENDING)) {
459 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
460 				"%s(%s): ABORT - PASSIVE XID",
461 					CTCM_FUNTAIL, dev->name);
462 			break;
463 		}
464 		grp->send_qllc_disc = 1;
465 		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIT);
466 		fsm_deltimer(&grp->timer);
467 		fsm_addtimer(&grp->timer, MPC_XID_TIMEOUT_VALUE,
468 						MPCG_EVENT_TIMER, dev);
469 		grp->outstanding_xid7 = 0;
470 		grp->outstanding_xid7_p2 = 0;
471 		grp->saved_xid2 = NULL;
472 		if ((rch->in_mpcgroup) &&
473 				(fsm_getstate(rch->fsm) == CH_XID0_PENDING))
474 			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, rch);
475 		else {
476 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
477 				"%s(%s): RX-%s not ready for ACTIVE XID0",
478 					CTCM_FUNTAIL, dev->name, rch->id);
479 			if (grp->estconnfunc) {
480 				grp->estconnfunc(grp->port_num, -1, 0);
481 				grp->estconnfunc = NULL;
482 			}
483 			fsm_deltimer(&grp->timer);
484 				goto done;
485 		}
486 		if ((wch->in_mpcgroup) &&
487 				(fsm_getstate(wch->fsm) == CH_XID0_PENDING))
488 			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, wch);
489 		else {
490 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
491 				"%s(%s): WX-%s not ready for ACTIVE XID0",
492 					CTCM_FUNTAIL, dev->name, wch->id);
493 			if (grp->estconnfunc) {
494 				grp->estconnfunc(grp->port_num, -1, 0);
495 				grp->estconnfunc = NULL;
496 			}
497 			fsm_deltimer(&grp->timer);
498 				goto done;
499 			}
500 		break;
501 	case MPCG_STATE_XID0IOWAIT:
502 		/* already in active XID negotiations */
503 	default:
504 		break;
505 	}
506 
507 done:
508 	CTCM_PR_DEBUG("Exit %s()\n", __func__);
509 	return;
510 }
511 EXPORT_SYMBOL(ctc_mpc_establish_connectivity);
512 
513 /*
514  * ctc_mpc_dealloc_ch
515  *	(exported interface)
516  */
517 void ctc_mpc_dealloc_ch(int port_num)
518 {
519 	struct net_device *dev;
520 	struct ctcm_priv *priv;
521 	struct mpc_group *grp;
522 
523 	dev = ctcmpc_get_dev(port_num);
524 	if (dev == NULL)
525 		return;
526 	priv = dev->ml_priv;
527 	grp = priv->mpcg;
528 
529 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_DEBUG,
530 			"%s: %s: refcount = %d\n",
531 			CTCM_FUNTAIL, dev->name, netdev_refcnt_read(dev));
532 
533 	fsm_deltimer(&priv->restart_timer);
534 	grp->channels_terminating = 0;
535 	fsm_deltimer(&grp->timer);
536 	grp->allochanfunc = NULL;
537 	grp->estconnfunc = NULL;
538 	grp->port_persist = 0;
539 	grp->send_qllc_disc = 0;
540 	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
541 
542 	ctcm_close(dev);
543 	return;
544 }
545 EXPORT_SYMBOL(ctc_mpc_dealloc_ch);
546 
547 /*
548  * ctc_mpc_flow_control
549  *	(exported interface)
550  */
551 void ctc_mpc_flow_control(int port_num, int flowc)
552 {
553 	struct ctcm_priv *priv;
554 	struct mpc_group *grp;
555 	struct net_device *dev;
556 	struct channel *rch;
557 	int mpcg_state;
558 
559 	dev = ctcmpc_get_dev(port_num);
560 	if (dev == NULL)
561 		return;
562 	priv = dev->ml_priv;
563 	grp = priv->mpcg;
564 
565 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
566 			"%s: %s: flowc = %d",
567 				CTCM_FUNTAIL, dev->name, flowc);
568 
569 	rch = priv->channel[CTCM_READ];
570 
571 	mpcg_state = fsm_getstate(grp->fsm);
572 	switch (flowc) {
573 	case 1:
574 		if (mpcg_state == MPCG_STATE_FLOWC)
575 			break;
576 		if (mpcg_state == MPCG_STATE_READY) {
577 			if (grp->flow_off_called == 1)
578 				grp->flow_off_called = 0;
579 			else
580 				fsm_newstate(grp->fsm, MPCG_STATE_FLOWC);
581 			break;
582 		}
583 		break;
584 	case 0:
585 		if (mpcg_state == MPCG_STATE_FLOWC) {
586 			fsm_newstate(grp->fsm, MPCG_STATE_READY);
587 			/* ensure any data that has accumulated */
588 			/* on the io_queue will now be sen t	*/
589 			tasklet_schedule(&rch->ch_tasklet);
590 		}
591 		/* possible race condition			*/
592 		if (mpcg_state == MPCG_STATE_READY) {
593 			grp->flow_off_called = 1;
594 			break;
595 		}
596 		break;
597 	}
598 
599 }
600 EXPORT_SYMBOL(ctc_mpc_flow_control);
601 
602 static int mpc_send_qllc_discontact(struct net_device *);
603 
604 /*
605  * helper function of ctcmpc_unpack_skb
606 */
607 static void mpc_rcvd_sweep_resp(struct mpcg_info *mpcginfo)
608 {
609 	struct channel	  *rch = mpcginfo->ch;
610 	struct net_device *dev = rch->netdev;
611 	struct ctcm_priv   *priv = dev->ml_priv;
612 	struct mpc_group  *grp = priv->mpcg;
613 	struct channel	  *ch = priv->channel[CTCM_WRITE];
614 
615 	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, ch, ch->id);
616 	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
617 
618 	grp->sweep_rsp_pend_num--;
619 
620 	if ((grp->sweep_req_pend_num == 0) &&
621 			(grp->sweep_rsp_pend_num == 0)) {
622 		fsm_deltimer(&ch->sweep_timer);
623 		grp->in_sweep = 0;
624 		rch->th_seq_num = 0x00;
625 		ch->th_seq_num = 0x00;
626 		ctcm_clear_busy_do(dev);
627 	}
628 
629 	return;
630 
631 }
632 
633 /*
634  * helper function of mpc_rcvd_sweep_req
635  * which is a helper of ctcmpc_unpack_skb
636  */
637 static void ctcmpc_send_sweep_resp(struct channel *rch)
638 {
639 	struct net_device *dev = rch->netdev;
640 	struct ctcm_priv *priv = dev->ml_priv;
641 	struct mpc_group *grp = priv->mpcg;
642 	struct th_sweep *header;
643 	struct sk_buff *sweep_skb;
644 	struct channel *ch  = priv->channel[CTCM_WRITE];
645 
646 	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, rch, rch->id);
647 
648 	sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
649 	if (sweep_skb == NULL) {
650 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
651 			"%s(%s): sweep_skb allocation ERROR\n",
652 			CTCM_FUNTAIL, rch->id);
653 		goto done;
654 	}
655 
656 	header = skb_put_zero(sweep_skb, TH_SWEEP_LENGTH);
657 	header->th.th_ch_flag	= TH_SWEEP_RESP;
658 	header->sw.th_last_seq	= ch->th_seq_num;
659 
660 	netif_trans_update(dev);
661 	skb_queue_tail(&ch->sweep_queue, sweep_skb);
662 
663 	fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
664 
665 	return;
666 
667 done:
668 	grp->in_sweep = 0;
669 	ctcm_clear_busy_do(dev);
670 	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
671 
672 	return;
673 }
674 
675 /*
676  * helper function of ctcmpc_unpack_skb
677  */
678 static void mpc_rcvd_sweep_req(struct mpcg_info *mpcginfo)
679 {
680 	struct channel	  *rch     = mpcginfo->ch;
681 	struct net_device *dev     = rch->netdev;
682 	struct ctcm_priv  *priv = dev->ml_priv;
683 	struct mpc_group  *grp  = priv->mpcg;
684 	struct channel	  *ch	   = priv->channel[CTCM_WRITE];
685 
686 	if (do_debug)
687 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
688 			" %s(): ch=0x%p id=%s\n", __func__, ch, ch->id);
689 
690 	if (grp->in_sweep == 0) {
691 		grp->in_sweep = 1;
692 		ctcm_test_and_set_busy(dev);
693 		grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
694 		grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
695 	}
696 
697 	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
698 
699 	grp->sweep_req_pend_num--;
700 	ctcmpc_send_sweep_resp(ch);
701 	kfree(mpcginfo);
702 	return;
703 }
704 
705 /*
706   * MPC Group Station FSM definitions
707  */
708 static const char *mpcg_event_names[] = {
709 	[MPCG_EVENT_INOP]	= "INOP Condition",
710 	[MPCG_EVENT_DISCONC]	= "Discontact Received",
711 	[MPCG_EVENT_XID0DO]	= "Channel Active - Start XID",
712 	[MPCG_EVENT_XID2]	= "XID2 Received",
713 	[MPCG_EVENT_XID2DONE]	= "XID0 Complete",
714 	[MPCG_EVENT_XID7DONE]	= "XID7 Complete",
715 	[MPCG_EVENT_TIMER]	= "XID Setup Timer",
716 	[MPCG_EVENT_DOIO]	= "XID DoIO",
717 };
718 
719 static const char *mpcg_state_names[] = {
720 	[MPCG_STATE_RESET]	= "Reset",
721 	[MPCG_STATE_INOP]	= "INOP",
722 	[MPCG_STATE_XID2INITW]	= "Passive XID- XID0 Pending Start",
723 	[MPCG_STATE_XID2INITX]	= "Passive XID- XID0 Pending Complete",
724 	[MPCG_STATE_XID7INITW]	= "Passive XID- XID7 Pending P1 Start",
725 	[MPCG_STATE_XID7INITX]	= "Passive XID- XID7 Pending P2 Complete",
726 	[MPCG_STATE_XID0IOWAIT]	= "Active  XID- XID0 Pending Start",
727 	[MPCG_STATE_XID0IOWAIX]	= "Active  XID- XID0 Pending Complete",
728 	[MPCG_STATE_XID7INITI]	= "Active  XID- XID7 Pending Start",
729 	[MPCG_STATE_XID7INITZ]	= "Active  XID- XID7 Pending Complete ",
730 	[MPCG_STATE_XID7INITF]	= "XID        - XID7 Complete ",
731 	[MPCG_STATE_FLOWC]	= "FLOW CONTROL ON",
732 	[MPCG_STATE_READY]	= "READY",
733 };
734 
735 /*
736  * The MPC Group Station FSM
737  *   22 events
738  */
739 static const fsm_node mpcg_fsm[] = {
740 	{ MPCG_STATE_RESET,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
741 	{ MPCG_STATE_INOP,	MPCG_EVENT_INOP,	mpc_action_nop        },
742 	{ MPCG_STATE_FLOWC,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
743 
744 	{ MPCG_STATE_READY,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
745 	{ MPCG_STATE_READY,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
746 
747 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
748 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
749 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
750 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
751 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
752 
753 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
754 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
755 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
756 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
757 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
758 
759 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
760 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
761 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
762 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
763 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
764 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
765 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
766 
767 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
768 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
769 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
770 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
771 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
772 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
773 
774 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
775 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DISCONC,	mpc_action_discontact },
776 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
777 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_INOP,	mpc_action_go_inop    },
778 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_TIMER,	mpc_action_timeout    },
779 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
780 
781 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
782 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DISCONC,	mpc_action_discontact },
783 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
784 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_INOP,	mpc_action_go_inop    },
785 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_TIMER,	mpc_action_timeout    },
786 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
787 
788 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
789 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
790 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
791 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
792 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
793 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
794 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
795 
796 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
797 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
798 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
799 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
800 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
801 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
802 
803 	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
804 	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_XID7DONE,	mpc_action_go_ready   },
805 };
806 
807 static int mpcg_fsm_len = ARRAY_SIZE(mpcg_fsm);
808 
809 /*
810  * MPC Group Station FSM action
811  * CTCM_PROTO_MPC only
812  */
813 static void mpc_action_go_ready(fsm_instance *fsm, int event, void *arg)
814 {
815 	struct net_device *dev = arg;
816 	struct ctcm_priv *priv = dev->ml_priv;
817 	struct mpc_group *grp = priv->mpcg;
818 
819 	if (grp == NULL) {
820 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
821 			"%s(%s): No MPC group",
822 				CTCM_FUNTAIL, dev->name);
823 		return;
824 	}
825 
826 	fsm_deltimer(&grp->timer);
827 
828 	if (grp->saved_xid2->xid2_flag2 == 0x40) {
829 		priv->xid->xid2_flag2 = 0x00;
830 		if (grp->estconnfunc) {
831 			grp->estconnfunc(grp->port_num, 1,
832 					grp->group_max_buflen);
833 			grp->estconnfunc = NULL;
834 		} else if (grp->allochanfunc)
835 			grp->send_qllc_disc = 1;
836 
837 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
838 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
839 				"%s(%s): fails",
840 					CTCM_FUNTAIL, dev->name);
841 		return;
842 	}
843 
844 	grp->port_persist = 1;
845 	grp->out_of_sequence = 0;
846 	grp->estconn_called = 0;
847 
848 	tasklet_hi_schedule(&grp->mpc_tasklet2);
849 
850 	return;
851 }
852 
853 /*
854  * helper of ctcm_init_netdevice
855  * CTCM_PROTO_MPC only
856  */
857 void mpc_group_ready(unsigned long adev)
858 {
859 	struct net_device *dev = (struct net_device *)adev;
860 	struct ctcm_priv *priv = dev->ml_priv;
861 	struct mpc_group *grp = priv->mpcg;
862 	struct channel *ch = NULL;
863 
864 	if (grp == NULL) {
865 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
866 			"%s(%s): No MPC group",
867 				CTCM_FUNTAIL, dev->name);
868 		return;
869 	}
870 
871 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
872 		"%s: %s: GROUP TRANSITIONED TO READY, maxbuf = %d\n",
873 			CTCM_FUNTAIL, dev->name, grp->group_max_buflen);
874 
875 	fsm_newstate(grp->fsm, MPCG_STATE_READY);
876 
877 	/* Put up a read on the channel */
878 	ch = priv->channel[CTCM_READ];
879 	ch->pdu_seq = 0;
880 	CTCM_PR_DBGDATA("ctcmpc: %s() ToDCM_pdu_seq= %08x\n" ,
881 			__func__, ch->pdu_seq);
882 
883 	ctcmpc_chx_rxidle(ch->fsm, CTC_EVENT_START, ch);
884 	/* Put the write channel in idle state */
885 	ch = priv->channel[CTCM_WRITE];
886 	if (ch->collect_len > 0) {
887 		spin_lock(&ch->collect_lock);
888 		ctcm_purge_skb_queue(&ch->collect_queue);
889 		ch->collect_len = 0;
890 		spin_unlock(&ch->collect_lock);
891 	}
892 	ctcm_chx_txidle(ch->fsm, CTC_EVENT_START, ch);
893 	ctcm_clear_busy(dev);
894 
895 	if (grp->estconnfunc) {
896 		grp->estconnfunc(grp->port_num, 0,
897 				    grp->group_max_buflen);
898 		grp->estconnfunc = NULL;
899 	} else 	if (grp->allochanfunc)
900 		grp->allochanfunc(grp->port_num, grp->group_max_buflen);
901 
902 	grp->send_qllc_disc = 1;
903 	grp->changed_side = 0;
904 
905 	return;
906 
907 }
908 
909 /*
910  * Increment the MPC Group Active Channel Counts
911  * helper of dev_action (called from channel fsm)
912  */
913 void mpc_channel_action(struct channel *ch, int direction, int action)
914 {
915 	struct net_device  *dev  = ch->netdev;
916 	struct ctcm_priv   *priv = dev->ml_priv;
917 	struct mpc_group   *grp  = priv->mpcg;
918 
919 	if (grp == NULL) {
920 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
921 			"%s(%s): No MPC group",
922 				CTCM_FUNTAIL, dev->name);
923 		return;
924 	}
925 
926 	CTCM_PR_DEBUG("enter %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
927 
928 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
929 		"%s: %i / Grp:%s total_channels=%i, active_channels: "
930 		"read=%i, write=%i\n", __func__, action,
931 		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
932 		grp->active_channels[CTCM_READ],
933 		grp->active_channels[CTCM_WRITE]);
934 
935 	if ((action == MPC_CHANNEL_ADD) && (ch->in_mpcgroup == 0)) {
936 		grp->num_channel_paths++;
937 		grp->active_channels[direction]++;
938 		grp->outstanding_xid2++;
939 		ch->in_mpcgroup = 1;
940 
941 		if (ch->xid_skb != NULL)
942 			dev_kfree_skb_any(ch->xid_skb);
943 
944 		ch->xid_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT,
945 					GFP_ATOMIC | GFP_DMA);
946 		if (ch->xid_skb == NULL) {
947 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
948 				"%s(%s): Couldn't alloc ch xid_skb\n",
949 				CTCM_FUNTAIL, dev->name);
950 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
951 			return;
952 		}
953 		ch->xid_skb_data = ch->xid_skb->data;
954 		ch->xid_th = (struct th_header *)ch->xid_skb->data;
955 		skb_put(ch->xid_skb, TH_HEADER_LENGTH);
956 		ch->xid = (struct xid2 *)skb_tail_pointer(ch->xid_skb);
957 		skb_put(ch->xid_skb, XID2_LENGTH);
958 		ch->xid_id = skb_tail_pointer(ch->xid_skb);
959 		ch->xid_skb->data = ch->xid_skb_data;
960 		skb_reset_tail_pointer(ch->xid_skb);
961 		ch->xid_skb->len = 0;
962 
963 		skb_put_data(ch->xid_skb, grp->xid_skb->data,
964 			     grp->xid_skb->len);
965 
966 		ch->xid->xid2_dlc_type =
967 			((CHANNEL_DIRECTION(ch->flags) == CTCM_READ)
968 				? XID2_READ_SIDE : XID2_WRITE_SIDE);
969 
970 		if (CHANNEL_DIRECTION(ch->flags) == CTCM_WRITE)
971 			ch->xid->xid2_buf_len = 0x00;
972 
973 		ch->xid_skb->data = ch->xid_skb_data;
974 		skb_reset_tail_pointer(ch->xid_skb);
975 		ch->xid_skb->len = 0;
976 
977 		fsm_newstate(ch->fsm, CH_XID0_PENDING);
978 
979 		if ((grp->active_channels[CTCM_READ] > 0) &&
980 		    (grp->active_channels[CTCM_WRITE] > 0) &&
981 			(fsm_getstate(grp->fsm) < MPCG_STATE_XID2INITW)) {
982 			fsm_newstate(grp->fsm, MPCG_STATE_XID2INITW);
983 			CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
984 				"%s: %s: MPC GROUP CHANNELS ACTIVE\n",
985 						__func__, dev->name);
986 		}
987 	} else if ((action == MPC_CHANNEL_REMOVE) &&
988 			(ch->in_mpcgroup == 1)) {
989 		ch->in_mpcgroup = 0;
990 		grp->num_channel_paths--;
991 		grp->active_channels[direction]--;
992 
993 		if (ch->xid_skb != NULL)
994 			dev_kfree_skb_any(ch->xid_skb);
995 		ch->xid_skb = NULL;
996 
997 		if (grp->channels_terminating)
998 					goto done;
999 
1000 		if (((grp->active_channels[CTCM_READ] == 0) &&
1001 					(grp->active_channels[CTCM_WRITE] > 0))
1002 			|| ((grp->active_channels[CTCM_WRITE] == 0) &&
1003 					(grp->active_channels[CTCM_READ] > 0)))
1004 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1005 	}
1006 done:
1007 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
1008 		"exit %s: %i / Grp:%s total_channels=%i, active_channels: "
1009 		"read=%i, write=%i\n", __func__, action,
1010 		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
1011 		grp->active_channels[CTCM_READ],
1012 		grp->active_channels[CTCM_WRITE]);
1013 
1014 	CTCM_PR_DEBUG("exit %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
1015 }
1016 
1017 /*
1018  * Unpack a just received skb and hand it over to
1019  * upper layers.
1020  * special MPC version of unpack_skb.
1021  *
1022  * ch		The channel where this skb has been received.
1023  * pskb		The received skb.
1024  */
1025 static void ctcmpc_unpack_skb(struct channel *ch, struct sk_buff *pskb)
1026 {
1027 	struct net_device *dev	= ch->netdev;
1028 	struct ctcm_priv *priv = dev->ml_priv;
1029 	struct mpc_group *grp = priv->mpcg;
1030 	struct pdu *curr_pdu;
1031 	struct mpcg_info *mpcginfo;
1032 	struct th_header *header = NULL;
1033 	struct th_sweep *sweep = NULL;
1034 	int pdu_last_seen = 0;
1035 	__u32 new_len;
1036 	struct sk_buff *skb;
1037 	int skblen;
1038 	int sendrc = 0;
1039 
1040 	CTCM_PR_DEBUG("ctcmpc enter: %s() %s cp:%i ch:%s\n",
1041 			__func__, dev->name, smp_processor_id(), ch->id);
1042 
1043 	header = (struct th_header *)pskb->data;
1044 	if ((header->th_seg == 0) &&
1045 		(header->th_ch_flag == 0) &&
1046 		(header->th_blk_flag == 0) &&
1047 		(header->th_seq_num == 0))
1048 		/* nothing for us */	goto done;
1049 
1050 	CTCM_PR_DBGDATA("%s: th_header\n", __func__);
1051 	CTCM_D3_DUMP((char *)header, TH_HEADER_LENGTH);
1052 	CTCM_PR_DBGDATA("%s: pskb len: %04x \n", __func__, pskb->len);
1053 
1054 	pskb->dev = dev;
1055 	pskb->ip_summed = CHECKSUM_UNNECESSARY;
1056 	skb_pull(pskb, TH_HEADER_LENGTH);
1057 
1058 	if (likely(header->th_ch_flag == TH_HAS_PDU)) {
1059 		CTCM_PR_DBGDATA("%s: came into th_has_pdu\n", __func__);
1060 		if ((fsm_getstate(grp->fsm) == MPCG_STATE_FLOWC) ||
1061 		   ((fsm_getstate(grp->fsm) == MPCG_STATE_READY) &&
1062 		    (header->th_seq_num != ch->th_seq_num + 1) &&
1063 		    (ch->th_seq_num != 0))) {
1064 			/* This is NOT the next segment		*
1065 			 * we are not the correct race winner	*
1066 			 * go away and let someone else win	*
1067 			 * BUT..this only applies if xid negot	*
1068 			 * is done				*
1069 			*/
1070 			grp->out_of_sequence += 1;
1071 			__skb_push(pskb, TH_HEADER_LENGTH);
1072 			skb_queue_tail(&ch->io_queue, pskb);
1073 			CTCM_PR_DBGDATA("%s: th_seq_num expect:%08x "
1074 					"got:%08x\n", __func__,
1075 				ch->th_seq_num + 1, header->th_seq_num);
1076 
1077 			return;
1078 		}
1079 		grp->out_of_sequence = 0;
1080 		ch->th_seq_num = header->th_seq_num;
1081 
1082 		CTCM_PR_DBGDATA("ctcmpc: %s() FromVTAM_th_seq=%08x\n",
1083 					__func__, ch->th_seq_num);
1084 
1085 		if (unlikely(fsm_getstate(grp->fsm) != MPCG_STATE_READY))
1086 					goto done;
1087 		while ((pskb->len > 0) && !pdu_last_seen) {
1088 			curr_pdu = (struct pdu *)pskb->data;
1089 
1090 			CTCM_PR_DBGDATA("%s: pdu_header\n", __func__);
1091 			CTCM_D3_DUMP((char *)pskb->data, PDU_HEADER_LENGTH);
1092 			CTCM_PR_DBGDATA("%s: pskb len: %04x \n",
1093 						__func__, pskb->len);
1094 
1095 			skb_pull(pskb, PDU_HEADER_LENGTH);
1096 
1097 			if (curr_pdu->pdu_flag & PDU_LAST)
1098 				pdu_last_seen = 1;
1099 			if (curr_pdu->pdu_flag & PDU_CNTL)
1100 				pskb->protocol = htons(ETH_P_SNAP);
1101 			else
1102 				pskb->protocol = htons(ETH_P_SNA_DIX);
1103 
1104 			if ((pskb->len <= 0) || (pskb->len > ch->max_bufsize)) {
1105 				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1106 					"%s(%s): Dropping packet with "
1107 					"illegal siize %d",
1108 					CTCM_FUNTAIL, dev->name, pskb->len);
1109 
1110 				priv->stats.rx_dropped++;
1111 				priv->stats.rx_length_errors++;
1112 					goto done;
1113 			}
1114 			skb_reset_mac_header(pskb);
1115 			new_len = curr_pdu->pdu_offset;
1116 			CTCM_PR_DBGDATA("%s: new_len: %04x \n",
1117 						__func__, new_len);
1118 			if ((new_len == 0) || (new_len > pskb->len)) {
1119 				/* should never happen		    */
1120 				/* pskb len must be hosed...bail out */
1121 				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1122 					"%s(%s): non valid pdu_offset: %04x",
1123 					/* "data may be lost", */
1124 					CTCM_FUNTAIL, dev->name, new_len);
1125 				goto done;
1126 			}
1127 			skb = __dev_alloc_skb(new_len+4, GFP_ATOMIC);
1128 
1129 			if (!skb) {
1130 				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1131 					"%s(%s): MEMORY allocation error",
1132 						CTCM_FUNTAIL, dev->name);
1133 				priv->stats.rx_dropped++;
1134 				fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1135 						goto done;
1136 			}
1137 			skb_put_data(skb, pskb->data, new_len);
1138 
1139 			skb_reset_mac_header(skb);
1140 			skb->dev = pskb->dev;
1141 			skb->protocol = pskb->protocol;
1142 			skb->ip_summed = CHECKSUM_UNNECESSARY;
1143 			*((__u32 *) skb_push(skb, 4)) = ch->pdu_seq;
1144 			ch->pdu_seq++;
1145 
1146 			if (do_debug_data) {
1147 				ctcm_pr_debug("%s: ToDCM_pdu_seq= %08x\n",
1148 						__func__, ch->pdu_seq);
1149 				ctcm_pr_debug("%s: skb:%0lx "
1150 					"skb len: %d \n", __func__,
1151 					(unsigned long)skb, skb->len);
1152 				ctcm_pr_debug("%s: up to 32 bytes "
1153 					"of pdu_data sent\n", __func__);
1154 				ctcmpc_dump32((char *)skb->data, skb->len);
1155 			}
1156 
1157 			skblen = skb->len;
1158 			sendrc = netif_rx(skb);
1159 			priv->stats.rx_packets++;
1160 			priv->stats.rx_bytes += skblen;
1161 			skb_pull(pskb, new_len); /* point to next PDU */
1162 		}
1163 	} else {
1164 		mpcginfo = kmalloc(sizeof(struct mpcg_info), GFP_ATOMIC);
1165 		if (mpcginfo == NULL)
1166 					goto done;
1167 
1168 		mpcginfo->ch = ch;
1169 		mpcginfo->th = header;
1170 		mpcginfo->skb = pskb;
1171 		CTCM_PR_DEBUG("%s: Not PDU - may be control pkt\n",
1172 					__func__);
1173 		/*  it's a sweep?   */
1174 		sweep = (struct th_sweep *)pskb->data;
1175 		mpcginfo->sweep = sweep;
1176 		if (header->th_ch_flag == TH_SWEEP_REQ)
1177 			mpc_rcvd_sweep_req(mpcginfo);
1178 		else if (header->th_ch_flag == TH_SWEEP_RESP)
1179 			mpc_rcvd_sweep_resp(mpcginfo);
1180 		else if (header->th_blk_flag == TH_DATA_IS_XID) {
1181 			struct xid2 *thisxid = (struct xid2 *)pskb->data;
1182 			skb_pull(pskb, XID2_LENGTH);
1183 			mpcginfo->xid = thisxid;
1184 			fsm_event(grp->fsm, MPCG_EVENT_XID2, mpcginfo);
1185 		} else if (header->th_blk_flag == TH_DISCONTACT)
1186 			fsm_event(grp->fsm, MPCG_EVENT_DISCONC, mpcginfo);
1187 		else if (header->th_seq_num != 0) {
1188 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1189 				"%s(%s): control pkt expected\n",
1190 						CTCM_FUNTAIL, dev->name);
1191 			priv->stats.rx_dropped++;
1192 			/* mpcginfo only used for non-data transfers */
1193 			if (do_debug_data)
1194 				ctcmpc_dump_skb(pskb, -8);
1195 		}
1196 		kfree(mpcginfo);
1197 	}
1198 done:
1199 
1200 	dev_kfree_skb_any(pskb);
1201 	if (sendrc == NET_RX_DROP) {
1202 		dev_warn(&dev->dev,
1203 			"The network backlog for %s is exceeded, "
1204 			"package dropped\n", __func__);
1205 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1206 	}
1207 
1208 	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
1209 			__func__, dev->name, ch, ch->id);
1210 }
1211 
1212 /*
1213  * tasklet helper for mpc's skb unpacking.
1214  *
1215  * ch		The channel to work on.
1216  * Allow flow control back pressure to occur here.
1217  * Throttling back channel can result in excessive
1218  * channel inactivity and system deact of channel
1219  */
1220 void ctcmpc_bh(unsigned long thischan)
1221 {
1222 	struct channel	  *ch	= (struct channel *)thischan;
1223 	struct sk_buff	  *skb;
1224 	struct net_device *dev	= ch->netdev;
1225 	struct ctcm_priv  *priv	= dev->ml_priv;
1226 	struct mpc_group  *grp	= priv->mpcg;
1227 
1228 	CTCM_PR_DEBUG("%s cp:%i enter:  %s() %s\n",
1229 	       dev->name, smp_processor_id(), __func__, ch->id);
1230 	/* caller has requested driver to throttle back */
1231 	while ((fsm_getstate(grp->fsm) != MPCG_STATE_FLOWC) &&
1232 			(skb = skb_dequeue(&ch->io_queue))) {
1233 		ctcmpc_unpack_skb(ch, skb);
1234 		if (grp->out_of_sequence > 20) {
1235 			/* assume data loss has occurred if */
1236 			/* missing seq_num for extended     */
1237 			/* period of time		    */
1238 			grp->out_of_sequence = 0;
1239 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1240 			break;
1241 		}
1242 		if (skb == skb_peek(&ch->io_queue))
1243 			break;
1244 	}
1245 	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
1246 			__func__, dev->name, ch, ch->id);
1247 	return;
1248 }
1249 
1250 /*
1251  *  MPC Group Initializations
1252  */
1253 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv)
1254 {
1255 	struct mpc_group *grp;
1256 
1257 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
1258 			"Enter %s(%p)", CTCM_FUNTAIL, priv);
1259 
1260 	grp = kzalloc(sizeof(struct mpc_group), GFP_KERNEL);
1261 	if (grp == NULL)
1262 		return NULL;
1263 
1264 	grp->fsm = init_fsm("mpcg", mpcg_state_names, mpcg_event_names,
1265 			MPCG_NR_STATES, MPCG_NR_EVENTS, mpcg_fsm,
1266 			mpcg_fsm_len, GFP_KERNEL);
1267 	if (grp->fsm == NULL) {
1268 		kfree(grp);
1269 		return NULL;
1270 	}
1271 
1272 	fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1273 	fsm_settimer(grp->fsm, &grp->timer);
1274 
1275 	grp->xid_skb =
1276 		 __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
1277 	if (grp->xid_skb == NULL) {
1278 		kfree_fsm(grp->fsm);
1279 		kfree(grp);
1280 		return NULL;
1281 	}
1282 	/*  base xid for all channels in group  */
1283 	grp->xid_skb_data = grp->xid_skb->data;
1284 	grp->xid_th = (struct th_header *)grp->xid_skb->data;
1285 	skb_put_data(grp->xid_skb, &thnorm, TH_HEADER_LENGTH);
1286 
1287 	grp->xid = (struct xid2 *)skb_tail_pointer(grp->xid_skb);
1288 	skb_put_data(grp->xid_skb, &init_xid, XID2_LENGTH);
1289 	grp->xid->xid2_adj_id = jiffies | 0xfff00000;
1290 	grp->xid->xid2_sender_id = jiffies;
1291 
1292 	grp->xid_id = skb_tail_pointer(grp->xid_skb);
1293 	skb_put_data(grp->xid_skb, "VTAM", 4);
1294 
1295 	grp->rcvd_xid_skb =
1296 		__dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
1297 	if (grp->rcvd_xid_skb == NULL) {
1298 		kfree_fsm(grp->fsm);
1299 		dev_kfree_skb(grp->xid_skb);
1300 		kfree(grp);
1301 		return NULL;
1302 	}
1303 	grp->rcvd_xid_data = grp->rcvd_xid_skb->data;
1304 	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
1305 	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
1306 	grp->saved_xid2 = NULL;
1307 	priv->xid = grp->xid;
1308 	priv->mpcg = grp;
1309 	return grp;
1310 }
1311 
1312 /*
1313  * The MPC Group Station FSM
1314  */
1315 
1316 /*
1317  * MPC Group Station FSM actions
1318  * CTCM_PROTO_MPC only
1319  */
1320 
1321 /*
1322  * NOP action for statemachines
1323  */
1324 static void mpc_action_nop(fsm_instance *fi, int event, void *arg)
1325 {
1326 }
1327 
1328 /*
1329  * invoked when the device transitions to dev_stopped
1330  * MPC will stop each individual channel if a single XID failure
1331  * occurs, or will intitiate all channels be stopped if a GROUP
1332  * level failure occurs.
1333  */
1334 static void mpc_action_go_inop(fsm_instance *fi, int event, void *arg)
1335 {
1336 	struct net_device  *dev = arg;
1337 	struct ctcm_priv    *priv;
1338 	struct mpc_group *grp;
1339 	struct channel *wch;
1340 
1341 	CTCM_PR_DEBUG("Enter %s: %s\n",	__func__, dev->name);
1342 
1343 	priv  = dev->ml_priv;
1344 	grp =  priv->mpcg;
1345 	grp->flow_off_called = 0;
1346 	fsm_deltimer(&grp->timer);
1347 	if (grp->channels_terminating)
1348 			return;
1349 
1350 	grp->channels_terminating = 1;
1351 	grp->saved_state = fsm_getstate(grp->fsm);
1352 	fsm_newstate(grp->fsm, MPCG_STATE_INOP);
1353 	if (grp->saved_state > MPCG_STATE_XID7INITF)
1354 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1355 			"%s(%s): MPC GROUP INOPERATIVE",
1356 				CTCM_FUNTAIL, dev->name);
1357 	if ((grp->saved_state != MPCG_STATE_RESET) ||
1358 		/* dealloc_channel has been called */
1359 		(grp->port_persist == 0))
1360 		fsm_deltimer(&priv->restart_timer);
1361 
1362 	wch = priv->channel[CTCM_WRITE];
1363 
1364 	switch (grp->saved_state) {
1365 	case MPCG_STATE_RESET:
1366 	case MPCG_STATE_INOP:
1367 	case MPCG_STATE_XID2INITW:
1368 	case MPCG_STATE_XID0IOWAIT:
1369 	case MPCG_STATE_XID2INITX:
1370 	case MPCG_STATE_XID7INITW:
1371 	case MPCG_STATE_XID7INITX:
1372 	case MPCG_STATE_XID0IOWAIX:
1373 	case MPCG_STATE_XID7INITI:
1374 	case MPCG_STATE_XID7INITZ:
1375 	case MPCG_STATE_XID7INITF:
1376 		break;
1377 	case MPCG_STATE_FLOWC:
1378 	case MPCG_STATE_READY:
1379 	default:
1380 		tasklet_hi_schedule(&wch->ch_disc_tasklet);
1381 	}
1382 
1383 	grp->xid2_tgnum = 0;
1384 	grp->group_max_buflen = 0;  /*min of all received */
1385 	grp->outstanding_xid2 = 0;
1386 	grp->outstanding_xid7 = 0;
1387 	grp->outstanding_xid7_p2 = 0;
1388 	grp->saved_xid2 = NULL;
1389 	grp->xidnogood = 0;
1390 	grp->changed_side = 0;
1391 
1392 	grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
1393 	skb_reset_tail_pointer(grp->rcvd_xid_skb);
1394 	grp->rcvd_xid_skb->len = 0;
1395 	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
1396 	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
1397 
1398 	if (grp->send_qllc_disc == 1) {
1399 		grp->send_qllc_disc = 0;
1400 		mpc_send_qllc_discontact(dev);
1401 	}
1402 
1403 	/* DO NOT issue DEV_EVENT_STOP directly out of this code */
1404 	/* This can result in INOP of VTAM PU due to halting of  */
1405 	/* outstanding IO which causes a sense to be returned	 */
1406 	/* Only about 3 senses are allowed and then IOS/VTAM will*/
1407 	/* become unreachable without manual intervention	 */
1408 	if ((grp->port_persist == 1) || (grp->alloc_called)) {
1409 		grp->alloc_called = 0;
1410 		fsm_deltimer(&priv->restart_timer);
1411 		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_RESTART, dev);
1412 		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1413 		if (grp->saved_state > MPCG_STATE_XID7INITF)
1414 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
1415 				"%s(%s): MPC GROUP RECOVERY SCHEDULED",
1416 					CTCM_FUNTAIL, dev->name);
1417 	} else {
1418 		fsm_deltimer(&priv->restart_timer);
1419 		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_STOP, dev);
1420 		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1421 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
1422 			"%s(%s): NO MPC GROUP RECOVERY ATTEMPTED",
1423 						CTCM_FUNTAIL, dev->name);
1424 	}
1425 }
1426 
1427 /*
1428  * Handle mpc group  action timeout.
1429  * MPC Group Station FSM action
1430  * CTCM_PROTO_MPC only
1431  *
1432  * fi		An instance of an mpc_group fsm.
1433  * event	The event, just happened.
1434  * arg		Generic pointer, casted from net_device * upon call.
1435  */
1436 static void mpc_action_timeout(fsm_instance *fi, int event, void *arg)
1437 {
1438 	struct net_device *dev = arg;
1439 	struct ctcm_priv *priv;
1440 	struct mpc_group *grp;
1441 	struct channel *wch;
1442 	struct channel *rch;
1443 
1444 	priv = dev->ml_priv;
1445 	grp = priv->mpcg;
1446 	wch = priv->channel[CTCM_WRITE];
1447 	rch = priv->channel[CTCM_READ];
1448 
1449 	switch (fsm_getstate(grp->fsm)) {
1450 	case MPCG_STATE_XID2INITW:
1451 		/* Unless there is outstanding IO on the  */
1452 		/* channel just return and wait for ATTN  */
1453 		/* interrupt to begin XID negotiations	  */
1454 		if ((fsm_getstate(rch->fsm) == CH_XID0_PENDING) &&
1455 		   (fsm_getstate(wch->fsm) == CH_XID0_PENDING))
1456 			break;
1457 		fallthrough;
1458 	default:
1459 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1460 	}
1461 
1462 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
1463 			"%s: dev=%s exit",
1464 			CTCM_FUNTAIL, dev->name);
1465 	return;
1466 }
1467 
1468 /*
1469  * MPC Group Station FSM action
1470  * CTCM_PROTO_MPC only
1471  */
1472 void mpc_action_discontact(fsm_instance *fi, int event, void *arg)
1473 {
1474 	struct mpcg_info   *mpcginfo   = arg;
1475 	struct channel	   *ch	       = mpcginfo->ch;
1476 	struct net_device  *dev;
1477 	struct ctcm_priv   *priv;
1478 	struct mpc_group   *grp;
1479 
1480 	if (ch) {
1481 		dev = ch->netdev;
1482 		if (dev) {
1483 			priv = dev->ml_priv;
1484 			if (priv) {
1485 				CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1486 					"%s: %s: %s\n",
1487 					CTCM_FUNTAIL, dev->name, ch->id);
1488 				grp = priv->mpcg;
1489 				grp->send_qllc_disc = 1;
1490 				fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1491 			}
1492 		}
1493 	}
1494 
1495 	return;
1496 }
1497 
1498 /*
1499  * MPC Group Station - not part of FSM
1500  * CTCM_PROTO_MPC only
1501  * called from add_channel in ctcm_main.c
1502  */
1503 void mpc_action_send_discontact(unsigned long thischan)
1504 {
1505 	int rc;
1506 	struct channel	*ch = (struct channel *)thischan;
1507 	unsigned long	saveflags = 0;
1508 
1509 	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1510 	rc = ccw_device_start(ch->cdev, &ch->ccw[15], 0, 0xff, 0);
1511 	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1512 
1513 	if (rc != 0) {
1514 		ctcm_ccw_check_rc(ch, rc, (char *)__func__);
1515 	}
1516 
1517 	return;
1518 }
1519 
1520 
1521 /*
1522  * helper function of mpc FSM
1523  * CTCM_PROTO_MPC only
1524  * mpc_action_rcvd_xid7
1525 */
1526 static int mpc_validate_xid(struct mpcg_info *mpcginfo)
1527 {
1528 	struct channel	   *ch	 = mpcginfo->ch;
1529 	struct net_device  *dev  = ch->netdev;
1530 	struct ctcm_priv   *priv = dev->ml_priv;
1531 	struct mpc_group   *grp  = priv->mpcg;
1532 	struct xid2	   *xid  = mpcginfo->xid;
1533 	int	rc	 = 0;
1534 	__u64	our_id   = 0;
1535 	__u64   their_id = 0;
1536 	int	len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1537 
1538 	CTCM_PR_DEBUG("Enter %s: xid=%p\n", __func__, xid);
1539 
1540 	if (xid == NULL) {
1541 		rc = 1;
1542 		/* XID REJECTED: xid == NULL */
1543 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1544 			"%s(%s): xid = NULL",
1545 				CTCM_FUNTAIL, ch->id);
1546 			goto done;
1547 	}
1548 
1549 	CTCM_D3_DUMP((char *)xid, XID2_LENGTH);
1550 
1551 	/*the received direction should be the opposite of ours  */
1552 	if (((CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ? XID2_WRITE_SIDE :
1553 				XID2_READ_SIDE) != xid->xid2_dlc_type) {
1554 		rc = 2;
1555 		/* XID REJECTED: r/w channel pairing mismatch */
1556 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1557 			"%s(%s): r/w channel pairing mismatch",
1558 				CTCM_FUNTAIL, ch->id);
1559 			goto done;
1560 	}
1561 
1562 	if (xid->xid2_dlc_type == XID2_READ_SIDE) {
1563 		CTCM_PR_DEBUG("%s: grpmaxbuf:%d xid2buflen:%d\n", __func__,
1564 				grp->group_max_buflen, xid->xid2_buf_len);
1565 
1566 		if (grp->group_max_buflen == 0 || grp->group_max_buflen >
1567 						xid->xid2_buf_len - len)
1568 			grp->group_max_buflen = xid->xid2_buf_len - len;
1569 	}
1570 
1571 	if (grp->saved_xid2 == NULL) {
1572 		grp->saved_xid2 =
1573 			(struct xid2 *)skb_tail_pointer(grp->rcvd_xid_skb);
1574 
1575 		skb_put_data(grp->rcvd_xid_skb, xid, XID2_LENGTH);
1576 		grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
1577 
1578 		skb_reset_tail_pointer(grp->rcvd_xid_skb);
1579 		grp->rcvd_xid_skb->len = 0;
1580 
1581 		/* convert two 32 bit numbers into 1 64 bit for id compare */
1582 		our_id = (__u64)priv->xid->xid2_adj_id;
1583 		our_id = our_id << 32;
1584 		our_id = our_id + priv->xid->xid2_sender_id;
1585 		their_id = (__u64)xid->xid2_adj_id;
1586 		their_id = their_id << 32;
1587 		their_id = their_id + xid->xid2_sender_id;
1588 		/* lower id assume the xside role */
1589 		if (our_id < their_id) {
1590 			grp->roll = XSIDE;
1591 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1592 				"%s(%s): WE HAVE LOW ID - TAKE XSIDE",
1593 					CTCM_FUNTAIL, ch->id);
1594 		} else {
1595 			grp->roll = YSIDE;
1596 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1597 				"%s(%s): WE HAVE HIGH ID - TAKE YSIDE",
1598 					CTCM_FUNTAIL, ch->id);
1599 		}
1600 
1601 	} else {
1602 		if (xid->xid2_flag4 != grp->saved_xid2->xid2_flag4) {
1603 			rc = 3;
1604 			/* XID REJECTED: xid flag byte4 mismatch */
1605 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1606 				"%s(%s): xid flag byte4 mismatch",
1607 					CTCM_FUNTAIL, ch->id);
1608 		}
1609 		if (xid->xid2_flag2 == 0x40) {
1610 			rc = 4;
1611 			/* XID REJECTED - xid NOGOOD */
1612 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1613 				"%s(%s): xid NOGOOD",
1614 					CTCM_FUNTAIL, ch->id);
1615 		}
1616 		if (xid->xid2_adj_id != grp->saved_xid2->xid2_adj_id) {
1617 			rc = 5;
1618 			/* XID REJECTED - Adjacent Station ID Mismatch */
1619 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1620 				"%s(%s): Adjacent Station ID Mismatch",
1621 					CTCM_FUNTAIL, ch->id);
1622 		}
1623 		if (xid->xid2_sender_id != grp->saved_xid2->xid2_sender_id) {
1624 			rc = 6;
1625 			/* XID REJECTED - Sender Address Mismatch */
1626 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1627 				"%s(%s): Sender Address Mismatch",
1628 					CTCM_FUNTAIL, ch->id);
1629 		}
1630 	}
1631 done:
1632 	if (rc) {
1633 		dev_warn(&dev->dev,
1634 			"The XID used in the MPC protocol is not valid, "
1635 			"rc = %d\n", rc);
1636 		priv->xid->xid2_flag2 = 0x40;
1637 		grp->saved_xid2->xid2_flag2 = 0x40;
1638 	}
1639 
1640 	return rc;
1641 }
1642 
1643 /*
1644  * MPC Group Station FSM action
1645  * CTCM_PROTO_MPC only
1646  */
1647 static void mpc_action_side_xid(fsm_instance *fsm, void *arg, int side)
1648 {
1649 	struct channel *ch = arg;
1650 	int rc = 0;
1651 	int gotlock = 0;
1652 	unsigned long saveflags = 0;	/* avoids compiler warning with
1653 					   spin_unlock_irqrestore */
1654 
1655 	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
1656 			__func__, smp_processor_id(), ch, ch->id);
1657 
1658 	if (ctcm_checkalloc_buffer(ch))
1659 					goto done;
1660 
1661 	/*
1662 	 * skb data-buffer referencing:
1663 	 */
1664 	ch->trans_skb->data = ch->trans_skb_data;
1665 	skb_reset_tail_pointer(ch->trans_skb);
1666 	ch->trans_skb->len = 0;
1667 	/* result of the previous 3 statements is NOT always
1668 	 * already set after ctcm_checkalloc_buffer
1669 	 * because of possible reuse of the trans_skb
1670 	 */
1671 	memset(ch->trans_skb->data, 0, 16);
1672 	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
1673 	/* check is main purpose here: */
1674 	skb_put(ch->trans_skb, TH_HEADER_LENGTH);
1675 	ch->rcvd_xid = (struct xid2 *)skb_tail_pointer(ch->trans_skb);
1676 	/* check is main purpose here: */
1677 	skb_put(ch->trans_skb, XID2_LENGTH);
1678 	ch->rcvd_xid_id = skb_tail_pointer(ch->trans_skb);
1679 	/* cleanup back to startpoint */
1680 	ch->trans_skb->data = ch->trans_skb_data;
1681 	skb_reset_tail_pointer(ch->trans_skb);
1682 	ch->trans_skb->len = 0;
1683 
1684 	/* non-checking rewrite of above skb data-buffer referencing: */
1685 	/*
1686 	memset(ch->trans_skb->data, 0, 16);
1687 	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
1688 	ch->rcvd_xid = (struct xid2 *)(ch->trans_skb_data + TH_HEADER_LENGTH);
1689 	ch->rcvd_xid_id = ch->trans_skb_data + TH_HEADER_LENGTH + XID2_LENGTH;
1690 	 */
1691 
1692 	ch->ccw[8].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1693 	ch->ccw[8].count	= 0;
1694 	ch->ccw[8].cda		= 0x00;
1695 
1696 	if (!(ch->xid_th && ch->xid && ch->xid_id))
1697 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_INFO,
1698 			"%s(%s): xid_th=%p, xid=%p, xid_id=%p",
1699 			CTCM_FUNTAIL, ch->id, ch->xid_th, ch->xid, ch->xid_id);
1700 
1701 	if (side == XSIDE) {
1702 		/* mpc_action_xside_xid */
1703 		if (ch->xid_th == NULL)
1704 				goto done;
1705 		ch->ccw[9].cmd_code	= CCW_CMD_WRITE;
1706 		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1707 		ch->ccw[9].count	= TH_HEADER_LENGTH;
1708 		ch->ccw[9].cda		= virt_to_phys(ch->xid_th);
1709 
1710 		if (ch->xid == NULL)
1711 				goto done;
1712 		ch->ccw[10].cmd_code	= CCW_CMD_WRITE;
1713 		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1714 		ch->ccw[10].count	= XID2_LENGTH;
1715 		ch->ccw[10].cda		= virt_to_phys(ch->xid);
1716 
1717 		ch->ccw[11].cmd_code	= CCW_CMD_READ;
1718 		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1719 		ch->ccw[11].count	= TH_HEADER_LENGTH;
1720 		ch->ccw[11].cda		= virt_to_phys(ch->rcvd_xid_th);
1721 
1722 		ch->ccw[12].cmd_code	= CCW_CMD_READ;
1723 		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1724 		ch->ccw[12].count	= XID2_LENGTH;
1725 		ch->ccw[12].cda		= virt_to_phys(ch->rcvd_xid);
1726 
1727 		ch->ccw[13].cmd_code	= CCW_CMD_READ;
1728 		ch->ccw[13].cda		= virt_to_phys(ch->rcvd_xid_id);
1729 
1730 	} else { /* side == YSIDE : mpc_action_yside_xid */
1731 		ch->ccw[9].cmd_code	= CCW_CMD_READ;
1732 		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1733 		ch->ccw[9].count	= TH_HEADER_LENGTH;
1734 		ch->ccw[9].cda		= virt_to_phys(ch->rcvd_xid_th);
1735 
1736 		ch->ccw[10].cmd_code	= CCW_CMD_READ;
1737 		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1738 		ch->ccw[10].count	= XID2_LENGTH;
1739 		ch->ccw[10].cda		= virt_to_phys(ch->rcvd_xid);
1740 
1741 		if (ch->xid_th == NULL)
1742 				goto done;
1743 		ch->ccw[11].cmd_code	= CCW_CMD_WRITE;
1744 		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1745 		ch->ccw[11].count	= TH_HEADER_LENGTH;
1746 		ch->ccw[11].cda		= virt_to_phys(ch->xid_th);
1747 
1748 		if (ch->xid == NULL)
1749 				goto done;
1750 		ch->ccw[12].cmd_code	= CCW_CMD_WRITE;
1751 		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1752 		ch->ccw[12].count	= XID2_LENGTH;
1753 		ch->ccw[12].cda		= virt_to_phys(ch->xid);
1754 
1755 		if (ch->xid_id == NULL)
1756 				goto done;
1757 		ch->ccw[13].cmd_code	= CCW_CMD_WRITE;
1758 		ch->ccw[13].cda		= virt_to_phys(ch->xid_id);
1759 
1760 	}
1761 	ch->ccw[13].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1762 	ch->ccw[13].count	= 4;
1763 
1764 	ch->ccw[14].cmd_code	= CCW_CMD_NOOP;
1765 	ch->ccw[14].flags	= CCW_FLAG_SLI;
1766 	ch->ccw[14].count	= 0;
1767 	ch->ccw[14].cda		= 0;
1768 
1769 	CTCM_CCW_DUMP((char *)&ch->ccw[8], sizeof(struct ccw1) * 7);
1770 	CTCM_D3_DUMP((char *)ch->xid_th, TH_HEADER_LENGTH);
1771 	CTCM_D3_DUMP((char *)ch->xid, XID2_LENGTH);
1772 	CTCM_D3_DUMP((char *)ch->xid_id, 4);
1773 
1774 	if (!in_hardirq()) {
1775 			 /* Such conditional locking is a known problem for
1776 			  * sparse because its static undeterministic.
1777 			  * Warnings should be ignored here. */
1778 		spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1779 		gotlock = 1;
1780 	}
1781 
1782 	fsm_addtimer(&ch->timer, 5000 , CTC_EVENT_TIMER, ch);
1783 	rc = ccw_device_start(ch->cdev, &ch->ccw[8], 0, 0xff, 0);
1784 
1785 	if (gotlock)	/* see remark above about conditional locking */
1786 		spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1787 
1788 	if (rc != 0) {
1789 		ctcm_ccw_check_rc(ch, rc,
1790 				(side == XSIDE) ? "x-side XID" : "y-side XID");
1791 	}
1792 
1793 done:
1794 	CTCM_PR_DEBUG("Exit %s: ch=0x%p id=%s\n",
1795 				__func__, ch, ch->id);
1796 	return;
1797 
1798 }
1799 
1800 /*
1801  * MPC Group Station FSM action
1802  * CTCM_PROTO_MPC only
1803  */
1804 static void mpc_action_xside_xid(fsm_instance *fsm, int event, void *arg)
1805 {
1806 	mpc_action_side_xid(fsm, arg, XSIDE);
1807 }
1808 
1809 /*
1810  * MPC Group Station FSM action
1811  * CTCM_PROTO_MPC only
1812  */
1813 static void mpc_action_yside_xid(fsm_instance *fsm, int event, void *arg)
1814 {
1815 	mpc_action_side_xid(fsm, arg, YSIDE);
1816 }
1817 
1818 /*
1819  * MPC Group Station FSM action
1820  * CTCM_PROTO_MPC only
1821  */
1822 static void mpc_action_doxid0(fsm_instance *fsm, int event, void *arg)
1823 {
1824 	struct channel	   *ch   = arg;
1825 	struct net_device  *dev  = ch->netdev;
1826 	struct ctcm_priv   *priv = dev->ml_priv;
1827 	struct mpc_group   *grp  = priv->mpcg;
1828 
1829 	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
1830 			__func__, smp_processor_id(), ch, ch->id);
1831 
1832 	if (ch->xid == NULL) {
1833 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1834 			"%s(%s): ch->xid == NULL",
1835 				CTCM_FUNTAIL, dev->name);
1836 		return;
1837 	}
1838 
1839 	fsm_newstate(ch->fsm, CH_XID0_INPROGRESS);
1840 
1841 	ch->xid->xid2_option =	XID2_0;
1842 
1843 	switch (fsm_getstate(grp->fsm)) {
1844 	case MPCG_STATE_XID2INITW:
1845 	case MPCG_STATE_XID2INITX:
1846 		ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1847 		break;
1848 	case MPCG_STATE_XID0IOWAIT:
1849 	case MPCG_STATE_XID0IOWAIX:
1850 		ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1851 		break;
1852 	}
1853 
1854 	fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
1855 
1856 	return;
1857 }
1858 
1859 /*
1860  * MPC Group Station FSM action
1861  * CTCM_PROTO_MPC only
1862 */
1863 static void mpc_action_doxid7(fsm_instance *fsm, int event, void *arg)
1864 {
1865 	struct net_device *dev = arg;
1866 	struct ctcm_priv  *priv = dev->ml_priv;
1867 	struct mpc_group  *grp  = NULL;
1868 	int direction;
1869 	int send = 0;
1870 
1871 	if (priv)
1872 		grp = priv->mpcg;
1873 	if (grp == NULL)
1874 		return;
1875 
1876 	for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1877 		struct channel *ch = priv->channel[direction];
1878 		struct xid2 *thisxid = ch->xid;
1879 		ch->xid_skb->data = ch->xid_skb_data;
1880 		skb_reset_tail_pointer(ch->xid_skb);
1881 		ch->xid_skb->len = 0;
1882 		thisxid->xid2_option = XID2_7;
1883 		send = 0;
1884 
1885 		/* xid7 phase 1 */
1886 		if (grp->outstanding_xid7_p2 > 0) {
1887 			if (grp->roll == YSIDE) {
1888 				if (fsm_getstate(ch->fsm) == CH_XID7_PENDING1) {
1889 					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
1890 					ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1891 					skb_put_data(ch->xid_skb, &thdummy,
1892 						     TH_HEADER_LENGTH);
1893 					send = 1;
1894 				}
1895 			} else if (fsm_getstate(ch->fsm) < CH_XID7_PENDING2) {
1896 					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
1897 					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1898 					skb_put_data(ch->xid_skb, &thnorm,
1899 						     TH_HEADER_LENGTH);
1900 					send = 1;
1901 			}
1902 		} else {
1903 			/* xid7 phase 2 */
1904 			if (grp->roll == YSIDE) {
1905 				if (fsm_getstate(ch->fsm) < CH_XID7_PENDING4) {
1906 					fsm_newstate(ch->fsm, CH_XID7_PENDING4);
1907 					skb_put_data(ch->xid_skb, &thnorm,
1908 						     TH_HEADER_LENGTH);
1909 					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1910 					send = 1;
1911 				}
1912 			} else if (fsm_getstate(ch->fsm) == CH_XID7_PENDING3) {
1913 				fsm_newstate(ch->fsm, CH_XID7_PENDING4);
1914 				ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1915 				skb_put_data(ch->xid_skb, &thdummy,
1916 					     TH_HEADER_LENGTH);
1917 				send = 1;
1918 			}
1919 		}
1920 
1921 		if (send)
1922 			fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
1923 	}
1924 
1925 	return;
1926 }
1927 
1928 /*
1929  * MPC Group Station FSM action
1930  * CTCM_PROTO_MPC only
1931  */
1932 static void mpc_action_rcvd_xid0(fsm_instance *fsm, int event, void *arg)
1933 {
1934 
1935 	struct mpcg_info   *mpcginfo  = arg;
1936 	struct channel	   *ch   = mpcginfo->ch;
1937 	struct net_device  *dev  = ch->netdev;
1938 	struct ctcm_priv   *priv = dev->ml_priv;
1939 	struct mpc_group   *grp  = priv->mpcg;
1940 
1941 	CTCM_PR_DEBUG("%s: ch-id:%s xid2:%i xid7:%i xidt_p2:%i \n",
1942 			__func__, ch->id, grp->outstanding_xid2,
1943 			grp->outstanding_xid7, grp->outstanding_xid7_p2);
1944 
1945 	if (fsm_getstate(ch->fsm) < CH_XID7_PENDING)
1946 		fsm_newstate(ch->fsm, CH_XID7_PENDING);
1947 
1948 	grp->outstanding_xid2--;
1949 	grp->outstanding_xid7++;
1950 	grp->outstanding_xid7_p2++;
1951 
1952 	/* must change state before validating xid to */
1953 	/* properly handle interim interrupts received*/
1954 	switch (fsm_getstate(grp->fsm)) {
1955 	case MPCG_STATE_XID2INITW:
1956 		fsm_newstate(grp->fsm, MPCG_STATE_XID2INITX);
1957 		mpc_validate_xid(mpcginfo);
1958 		break;
1959 	case MPCG_STATE_XID0IOWAIT:
1960 		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIX);
1961 		mpc_validate_xid(mpcginfo);
1962 		break;
1963 	case MPCG_STATE_XID2INITX:
1964 		if (grp->outstanding_xid2 == 0) {
1965 			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITW);
1966 			mpc_validate_xid(mpcginfo);
1967 			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
1968 		}
1969 		break;
1970 	case MPCG_STATE_XID0IOWAIX:
1971 		if (grp->outstanding_xid2 == 0) {
1972 			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITI);
1973 			mpc_validate_xid(mpcginfo);
1974 			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
1975 		}
1976 		break;
1977 	}
1978 
1979 	CTCM_PR_DEBUG("ctcmpc:%s() %s xid2:%i xid7:%i xidt_p2:%i \n",
1980 		__func__, ch->id, grp->outstanding_xid2,
1981 		grp->outstanding_xid7, grp->outstanding_xid7_p2);
1982 	CTCM_PR_DEBUG("ctcmpc:%s() %s grpstate: %s chanstate: %s \n",
1983 		__func__, ch->id,
1984 		fsm_getstate_str(grp->fsm), fsm_getstate_str(ch->fsm));
1985 	return;
1986 
1987 }
1988 
1989 
1990 /*
1991  * MPC Group Station FSM action
1992  * CTCM_PROTO_MPC only
1993  */
1994 static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg)
1995 {
1996 	struct mpcg_info   *mpcginfo   = arg;
1997 	struct channel	   *ch	       = mpcginfo->ch;
1998 	struct net_device  *dev        = ch->netdev;
1999 	struct ctcm_priv   *priv    = dev->ml_priv;
2000 	struct mpc_group   *grp     = priv->mpcg;
2001 
2002 	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
2003 		__func__, smp_processor_id(), ch, ch->id);
2004 	CTCM_PR_DEBUG("%s: outstanding_xid7: %i, outstanding_xid7_p2: %i\n",
2005 		__func__, grp->outstanding_xid7, grp->outstanding_xid7_p2);
2006 
2007 	grp->outstanding_xid7--;
2008 	ch->xid_skb->data = ch->xid_skb_data;
2009 	skb_reset_tail_pointer(ch->xid_skb);
2010 	ch->xid_skb->len = 0;
2011 
2012 	switch (fsm_getstate(grp->fsm)) {
2013 	case MPCG_STATE_XID7INITI:
2014 		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITZ);
2015 		mpc_validate_xid(mpcginfo);
2016 		break;
2017 	case MPCG_STATE_XID7INITW:
2018 		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITX);
2019 		mpc_validate_xid(mpcginfo);
2020 		break;
2021 	case MPCG_STATE_XID7INITZ:
2022 	case MPCG_STATE_XID7INITX:
2023 		if (grp->outstanding_xid7 == 0) {
2024 			if (grp->outstanding_xid7_p2 > 0) {
2025 				grp->outstanding_xid7 =
2026 					grp->outstanding_xid7_p2;
2027 				grp->outstanding_xid7_p2 = 0;
2028 			} else
2029 				fsm_newstate(grp->fsm, MPCG_STATE_XID7INITF);
2030 
2031 			mpc_validate_xid(mpcginfo);
2032 			fsm_event(grp->fsm, MPCG_EVENT_XID7DONE, dev);
2033 			break;
2034 		}
2035 		mpc_validate_xid(mpcginfo);
2036 		break;
2037 	}
2038 	return;
2039 }
2040 
2041 /*
2042  * mpc_action helper of an MPC Group Station FSM action
2043  * CTCM_PROTO_MPC only
2044  */
2045 static int mpc_send_qllc_discontact(struct net_device *dev)
2046 {
2047 	struct sk_buff   *skb;
2048 	struct qllc      *qllcptr;
2049 	struct ctcm_priv *priv = dev->ml_priv;
2050 	struct mpc_group *grp = priv->mpcg;
2051 
2052 	CTCM_PR_DEBUG("%s: GROUP STATE: %s\n",
2053 		__func__, mpcg_state_names[grp->saved_state]);
2054 
2055 	switch (grp->saved_state) {
2056 	/*
2057 	 * establish conn callback function is
2058 	 * preferred method to report failure
2059 	 */
2060 	case MPCG_STATE_XID0IOWAIT:
2061 	case MPCG_STATE_XID0IOWAIX:
2062 	case MPCG_STATE_XID7INITI:
2063 	case MPCG_STATE_XID7INITZ:
2064 	case MPCG_STATE_XID2INITW:
2065 	case MPCG_STATE_XID2INITX:
2066 	case MPCG_STATE_XID7INITW:
2067 	case MPCG_STATE_XID7INITX:
2068 		if (grp->estconnfunc) {
2069 			grp->estconnfunc(grp->port_num, -1, 0);
2070 			grp->estconnfunc = NULL;
2071 			break;
2072 		}
2073 		fallthrough;
2074 	case MPCG_STATE_FLOWC:
2075 	case MPCG_STATE_READY:
2076 		grp->send_qllc_disc = 2;
2077 
2078 		skb = __dev_alloc_skb(sizeof(struct qllc), GFP_ATOMIC);
2079 		if (skb == NULL) {
2080 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2081 				"%s(%s): skb allocation error",
2082 						CTCM_FUNTAIL, dev->name);
2083 			priv->stats.rx_dropped++;
2084 			return -ENOMEM;
2085 		}
2086 
2087 		qllcptr = skb_put(skb, sizeof(struct qllc));
2088 		qllcptr->qllc_address = 0xcc;
2089 		qllcptr->qllc_commands = 0x03;
2090 
2091 		if (skb_headroom(skb) < 4) {
2092 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2093 				"%s(%s): skb_headroom error",
2094 						CTCM_FUNTAIL, dev->name);
2095 			dev_kfree_skb_any(skb);
2096 			return -ENOMEM;
2097 		}
2098 
2099 		*((__u32 *)skb_push(skb, 4)) =
2100 			priv->channel[CTCM_READ]->pdu_seq;
2101 		priv->channel[CTCM_READ]->pdu_seq++;
2102 		CTCM_PR_DBGDATA("ctcmpc: %s ToDCM_pdu_seq= %08x\n",
2103 				__func__, priv->channel[CTCM_READ]->pdu_seq);
2104 
2105 		/* receipt of CC03 resets anticipated sequence number on
2106 		      receiving side */
2107 		priv->channel[CTCM_READ]->pdu_seq = 0x00;
2108 		skb_reset_mac_header(skb);
2109 		skb->dev = dev;
2110 		skb->protocol = htons(ETH_P_SNAP);
2111 		skb->ip_summed = CHECKSUM_UNNECESSARY;
2112 
2113 		CTCM_D3_DUMP(skb->data, (sizeof(struct qllc) + 4));
2114 
2115 		netif_rx(skb);
2116 		break;
2117 	default:
2118 		break;
2119 
2120 	}
2121 
2122 	return 0;
2123 }
2124 /* --- This is the END my friend --- */
2125 
2126