xref: /openbmc/linux/drivers/s390/net/ctcm_mpc.c (revision e2c75e76)
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 	case MPCG_STATE_XID0IOWAIT:
361 		fsm_deltimer(&grp->timer);
362 		grp->outstanding_xid2 = 0;
363 		grp->outstanding_xid7 = 0;
364 		grp->outstanding_xid7_p2 = 0;
365 		grp->saved_xid2 = NULL;
366 		if (callback)
367 			ctcm_open(dev);
368 		fsm_event(priv->fsm, DEV_EVENT_START, dev);
369 		break;
370 	case MPCG_STATE_READY:
371 		/* XID exchanges completed after PORT was activated */
372 		/* Link station already active			    */
373 		/* Maybe timing issue...retry callback		    */
374 		grp->allocchan_callback_retries++;
375 		if (grp->allocchan_callback_retries < 4) {
376 			if (grp->allochanfunc)
377 				grp->allochanfunc(grp->port_num,
378 						  grp->group_max_buflen);
379 		} else {
380 			/* there are problems...bail out	    */
381 			/* there may be a state mismatch so restart */
382 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
383 			grp->allocchan_callback_retries = 0;
384 		}
385 		break;
386 	}
387 
388 	return 0;
389 }
390 EXPORT_SYMBOL(ctc_mpc_alloc_channel);
391 
392 /*
393  * ctc_mpc_establish_connectivity
394  *	(exported interface)
395  */
396 void ctc_mpc_establish_connectivity(int port_num,
397 				void (*callback)(int, int, int))
398 {
399 	struct net_device *dev;
400 	struct mpc_group *grp;
401 	struct ctcm_priv *priv;
402 	struct channel *rch, *wch;
403 
404 	dev = ctcmpc_get_dev(port_num);
405 	if (dev == NULL)
406 		return;
407 	priv = dev->ml_priv;
408 	grp = priv->mpcg;
409 	rch = priv->channel[CTCM_READ];
410 	wch = priv->channel[CTCM_WRITE];
411 
412 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
413 			"%s(%s): state=%s",
414 			CTCM_FUNTAIL, dev->name, fsm_getstate_str(grp->fsm));
415 
416 	grp->estconnfunc = callback;
417 	grp->port_num = port_num;
418 
419 	switch (fsm_getstate(grp->fsm)) {
420 	case MPCG_STATE_READY:
421 		/* XID exchanges completed after PORT was activated */
422 		/* Link station already active			    */
423 		/* Maybe timing issue...retry callback		    */
424 		fsm_deltimer(&grp->timer);
425 		grp->estconn_callback_retries++;
426 		if (grp->estconn_callback_retries < 4) {
427 			if (grp->estconnfunc) {
428 				grp->estconnfunc(grp->port_num, 0,
429 						grp->group_max_buflen);
430 				grp->estconnfunc = NULL;
431 			}
432 		} else {
433 			/* there are problems...bail out	 */
434 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
435 			grp->estconn_callback_retries = 0;
436 		}
437 		break;
438 	case MPCG_STATE_INOP:
439 	case MPCG_STATE_RESET:
440 		/* MPC Group is not ready to start XID - min num of */
441 		/* 1 read and 1 write channel have not been acquired*/
442 
443 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
444 			"%s(%s): REJECTED - inactive channels",
445 					CTCM_FUNTAIL, dev->name);
446 		if (grp->estconnfunc) {
447 			grp->estconnfunc(grp->port_num, -1, 0);
448 			grp->estconnfunc = NULL;
449 		}
450 		break;
451 	case MPCG_STATE_XID2INITW:
452 		/* alloc channel was called but no XID exchange    */
453 		/* has occurred. initiate xside XID exchange	   */
454 		/* make sure yside XID0 processing has not started */
455 
456 		if ((fsm_getstate(rch->fsm) > CH_XID0_PENDING) ||
457 			(fsm_getstate(wch->fsm) > CH_XID0_PENDING)) {
458 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
459 				"%s(%s): ABORT - PASSIVE XID",
460 					CTCM_FUNTAIL, dev->name);
461 			break;
462 		}
463 		grp->send_qllc_disc = 1;
464 		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIT);
465 		fsm_deltimer(&grp->timer);
466 		fsm_addtimer(&grp->timer, MPC_XID_TIMEOUT_VALUE,
467 						MPCG_EVENT_TIMER, dev);
468 		grp->outstanding_xid7 = 0;
469 		grp->outstanding_xid7_p2 = 0;
470 		grp->saved_xid2 = NULL;
471 		if ((rch->in_mpcgroup) &&
472 				(fsm_getstate(rch->fsm) == CH_XID0_PENDING))
473 			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, rch);
474 		else {
475 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
476 				"%s(%s): RX-%s not ready for ACTIVE XID0",
477 					CTCM_FUNTAIL, dev->name, rch->id);
478 			if (grp->estconnfunc) {
479 				grp->estconnfunc(grp->port_num, -1, 0);
480 				grp->estconnfunc = NULL;
481 			}
482 			fsm_deltimer(&grp->timer);
483 				goto done;
484 		}
485 		if ((wch->in_mpcgroup) &&
486 				(fsm_getstate(wch->fsm) == CH_XID0_PENDING))
487 			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, wch);
488 		else {
489 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
490 				"%s(%s): WX-%s not ready for ACTIVE XID0",
491 					CTCM_FUNTAIL, dev->name, wch->id);
492 			if (grp->estconnfunc) {
493 				grp->estconnfunc(grp->port_num, -1, 0);
494 				grp->estconnfunc = NULL;
495 			}
496 			fsm_deltimer(&grp->timer);
497 				goto done;
498 			}
499 		break;
500 	case MPCG_STATE_XID0IOWAIT:
501 		/* already in active XID negotiations */
502 	default:
503 		break;
504 	}
505 
506 done:
507 	CTCM_PR_DEBUG("Exit %s()\n", __func__);
508 	return;
509 }
510 EXPORT_SYMBOL(ctc_mpc_establish_connectivity);
511 
512 /*
513  * ctc_mpc_dealloc_ch
514  *	(exported interface)
515  */
516 void ctc_mpc_dealloc_ch(int port_num)
517 {
518 	struct net_device *dev;
519 	struct ctcm_priv *priv;
520 	struct mpc_group *grp;
521 
522 	dev = ctcmpc_get_dev(port_num);
523 	if (dev == NULL)
524 		return;
525 	priv = dev->ml_priv;
526 	grp = priv->mpcg;
527 
528 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_DEBUG,
529 			"%s: %s: refcount = %d\n",
530 			CTCM_FUNTAIL, dev->name, netdev_refcnt_read(dev));
531 
532 	fsm_deltimer(&priv->restart_timer);
533 	grp->channels_terminating = 0;
534 	fsm_deltimer(&grp->timer);
535 	grp->allochanfunc = NULL;
536 	grp->estconnfunc = NULL;
537 	grp->port_persist = 0;
538 	grp->send_qllc_disc = 0;
539 	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
540 
541 	ctcm_close(dev);
542 	return;
543 }
544 EXPORT_SYMBOL(ctc_mpc_dealloc_ch);
545 
546 /*
547  * ctc_mpc_flow_control
548  *	(exported interface)
549  */
550 void ctc_mpc_flow_control(int port_num, int flowc)
551 {
552 	struct ctcm_priv *priv;
553 	struct mpc_group *grp;
554 	struct net_device *dev;
555 	struct channel *rch;
556 	int mpcg_state;
557 
558 	dev = ctcmpc_get_dev(port_num);
559 	if (dev == NULL)
560 		return;
561 	priv = dev->ml_priv;
562 	grp = priv->mpcg;
563 
564 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
565 			"%s: %s: flowc = %d",
566 				CTCM_FUNTAIL, dev->name, flowc);
567 
568 	rch = priv->channel[CTCM_READ];
569 
570 	mpcg_state = fsm_getstate(grp->fsm);
571 	switch (flowc) {
572 	case 1:
573 		if (mpcg_state == MPCG_STATE_FLOWC)
574 			break;
575 		if (mpcg_state == MPCG_STATE_READY) {
576 			if (grp->flow_off_called == 1)
577 				grp->flow_off_called = 0;
578 			else
579 				fsm_newstate(grp->fsm, MPCG_STATE_FLOWC);
580 			break;
581 		}
582 		break;
583 	case 0:
584 		if (mpcg_state == MPCG_STATE_FLOWC) {
585 			fsm_newstate(grp->fsm, MPCG_STATE_READY);
586 			/* ensure any data that has accumulated */
587 			/* on the io_queue will now be sen t	*/
588 			tasklet_schedule(&rch->ch_tasklet);
589 		}
590 		/* possible race condition			*/
591 		if (mpcg_state == MPCG_STATE_READY) {
592 			grp->flow_off_called = 1;
593 			break;
594 		}
595 		break;
596 	}
597 
598 }
599 EXPORT_SYMBOL(ctc_mpc_flow_control);
600 
601 static int mpc_send_qllc_discontact(struct net_device *);
602 
603 /*
604  * helper function of ctcmpc_unpack_skb
605 */
606 static void mpc_rcvd_sweep_resp(struct mpcg_info *mpcginfo)
607 {
608 	struct channel	  *rch = mpcginfo->ch;
609 	struct net_device *dev = rch->netdev;
610 	struct ctcm_priv   *priv = dev->ml_priv;
611 	struct mpc_group  *grp = priv->mpcg;
612 	struct channel	  *ch = priv->channel[CTCM_WRITE];
613 
614 	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, ch, ch->id);
615 	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
616 
617 	grp->sweep_rsp_pend_num--;
618 
619 	if ((grp->sweep_req_pend_num == 0) &&
620 			(grp->sweep_rsp_pend_num == 0)) {
621 		fsm_deltimer(&ch->sweep_timer);
622 		grp->in_sweep = 0;
623 		rch->th_seq_num = 0x00;
624 		ch->th_seq_num = 0x00;
625 		ctcm_clear_busy_do(dev);
626 	}
627 
628 	kfree(mpcginfo);
629 
630 	return;
631 
632 }
633 
634 /*
635  * helper function of mpc_rcvd_sweep_req
636  * which is a helper of ctcmpc_unpack_skb
637  */
638 static void ctcmpc_send_sweep_resp(struct channel *rch)
639 {
640 	struct net_device *dev = rch->netdev;
641 	struct ctcm_priv *priv = dev->ml_priv;
642 	struct mpc_group *grp = priv->mpcg;
643 	struct th_sweep *header;
644 	struct sk_buff *sweep_skb;
645 	struct channel *ch  = priv->channel[CTCM_WRITE];
646 
647 	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, rch, rch->id);
648 
649 	sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
650 	if (sweep_skb == NULL) {
651 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
652 			"%s(%s): sweep_skb allocation ERROR\n",
653 			CTCM_FUNTAIL, rch->id);
654 		goto done;
655 	}
656 
657 	header = kmalloc(sizeof(struct th_sweep), gfp_type());
658 
659 	if (!header) {
660 		dev_kfree_skb_any(sweep_skb);
661 		goto done;
662 	}
663 
664 	header->th.th_seg	= 0x00 ;
665 	header->th.th_ch_flag	= TH_SWEEP_RESP;
666 	header->th.th_blk_flag	= 0x00;
667 	header->th.th_is_xid	= 0x00;
668 	header->th.th_seq_num	= 0x00;
669 	header->sw.th_last_seq	= ch->th_seq_num;
670 
671 	skb_put_data(sweep_skb, header, TH_SWEEP_LENGTH);
672 
673 	kfree(header);
674 
675 	netif_trans_update(dev);
676 	skb_queue_tail(&ch->sweep_queue, sweep_skb);
677 
678 	fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
679 
680 	return;
681 
682 done:
683 	grp->in_sweep = 0;
684 	ctcm_clear_busy_do(dev);
685 	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
686 
687 	return;
688 }
689 
690 /*
691  * helper function of ctcmpc_unpack_skb
692  */
693 static void mpc_rcvd_sweep_req(struct mpcg_info *mpcginfo)
694 {
695 	struct channel	  *rch     = mpcginfo->ch;
696 	struct net_device *dev     = rch->netdev;
697 	struct ctcm_priv  *priv = dev->ml_priv;
698 	struct mpc_group  *grp  = priv->mpcg;
699 	struct channel	  *ch	   = priv->channel[CTCM_WRITE];
700 
701 	if (do_debug)
702 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
703 			" %s(): ch=0x%p id=%s\n", __func__, ch, ch->id);
704 
705 	if (grp->in_sweep == 0) {
706 		grp->in_sweep = 1;
707 		ctcm_test_and_set_busy(dev);
708 		grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
709 		grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
710 	}
711 
712 	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
713 
714 	grp->sweep_req_pend_num--;
715 	ctcmpc_send_sweep_resp(ch);
716 	kfree(mpcginfo);
717 	return;
718 }
719 
720 /*
721   * MPC Group Station FSM definitions
722  */
723 static const char *mpcg_event_names[] = {
724 	[MPCG_EVENT_INOP]	= "INOP Condition",
725 	[MPCG_EVENT_DISCONC]	= "Discontact Received",
726 	[MPCG_EVENT_XID0DO]	= "Channel Active - Start XID",
727 	[MPCG_EVENT_XID2]	= "XID2 Received",
728 	[MPCG_EVENT_XID2DONE]	= "XID0 Complete",
729 	[MPCG_EVENT_XID7DONE]	= "XID7 Complete",
730 	[MPCG_EVENT_TIMER]	= "XID Setup Timer",
731 	[MPCG_EVENT_DOIO]	= "XID DoIO",
732 };
733 
734 static const char *mpcg_state_names[] = {
735 	[MPCG_STATE_RESET]	= "Reset",
736 	[MPCG_STATE_INOP]	= "INOP",
737 	[MPCG_STATE_XID2INITW]	= "Passive XID- XID0 Pending Start",
738 	[MPCG_STATE_XID2INITX]	= "Passive XID- XID0 Pending Complete",
739 	[MPCG_STATE_XID7INITW]	= "Passive XID- XID7 Pending P1 Start",
740 	[MPCG_STATE_XID7INITX]	= "Passive XID- XID7 Pending P2 Complete",
741 	[MPCG_STATE_XID0IOWAIT]	= "Active  XID- XID0 Pending Start",
742 	[MPCG_STATE_XID0IOWAIX]	= "Active  XID- XID0 Pending Complete",
743 	[MPCG_STATE_XID7INITI]	= "Active  XID- XID7 Pending Start",
744 	[MPCG_STATE_XID7INITZ]	= "Active  XID- XID7 Pending Complete ",
745 	[MPCG_STATE_XID7INITF]	= "XID        - XID7 Complete ",
746 	[MPCG_STATE_FLOWC]	= "FLOW CONTROL ON",
747 	[MPCG_STATE_READY]	= "READY",
748 };
749 
750 /*
751  * The MPC Group Station FSM
752  *   22 events
753  */
754 static const fsm_node mpcg_fsm[] = {
755 	{ MPCG_STATE_RESET,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
756 	{ MPCG_STATE_INOP,	MPCG_EVENT_INOP,	mpc_action_nop        },
757 	{ MPCG_STATE_FLOWC,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
758 
759 	{ MPCG_STATE_READY,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
760 	{ MPCG_STATE_READY,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
761 
762 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
763 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
764 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
765 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
766 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
767 
768 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
769 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
770 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
771 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
772 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
773 
774 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
775 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
776 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
777 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
778 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
779 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
780 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
781 
782 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
783 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
784 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
785 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
786 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
787 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
788 
789 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
790 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DISCONC,	mpc_action_discontact },
791 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
792 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_INOP,	mpc_action_go_inop    },
793 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_TIMER,	mpc_action_timeout    },
794 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
795 
796 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
797 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DISCONC,	mpc_action_discontact },
798 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
799 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_INOP,	mpc_action_go_inop    },
800 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_TIMER,	mpc_action_timeout    },
801 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
802 
803 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
804 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
805 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
806 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
807 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
808 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
809 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
810 
811 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
812 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
813 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
814 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
815 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
816 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
817 
818 	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
819 	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_XID7DONE,	mpc_action_go_ready   },
820 };
821 
822 static int mpcg_fsm_len = ARRAY_SIZE(mpcg_fsm);
823 
824 /*
825  * MPC Group Station FSM action
826  * CTCM_PROTO_MPC only
827  */
828 static void mpc_action_go_ready(fsm_instance *fsm, int event, void *arg)
829 {
830 	struct net_device *dev = arg;
831 	struct ctcm_priv *priv = dev->ml_priv;
832 	struct mpc_group *grp = priv->mpcg;
833 
834 	if (grp == NULL) {
835 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
836 			"%s(%s): No MPC group",
837 				CTCM_FUNTAIL, dev->name);
838 		return;
839 	}
840 
841 	fsm_deltimer(&grp->timer);
842 
843 	if (grp->saved_xid2->xid2_flag2 == 0x40) {
844 		priv->xid->xid2_flag2 = 0x00;
845 		if (grp->estconnfunc) {
846 			grp->estconnfunc(grp->port_num, 1,
847 					grp->group_max_buflen);
848 			grp->estconnfunc = NULL;
849 		} else if (grp->allochanfunc)
850 			grp->send_qllc_disc = 1;
851 
852 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
853 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
854 				"%s(%s): fails",
855 					CTCM_FUNTAIL, dev->name);
856 		return;
857 	}
858 
859 	grp->port_persist = 1;
860 	grp->out_of_sequence = 0;
861 	grp->estconn_called = 0;
862 
863 	tasklet_hi_schedule(&grp->mpc_tasklet2);
864 
865 	return;
866 }
867 
868 /*
869  * helper of ctcm_init_netdevice
870  * CTCM_PROTO_MPC only
871  */
872 void mpc_group_ready(unsigned long adev)
873 {
874 	struct net_device *dev = (struct net_device *)adev;
875 	struct ctcm_priv *priv = dev->ml_priv;
876 	struct mpc_group *grp = priv->mpcg;
877 	struct channel *ch = NULL;
878 
879 	if (grp == NULL) {
880 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
881 			"%s(%s): No MPC group",
882 				CTCM_FUNTAIL, dev->name);
883 		return;
884 	}
885 
886 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
887 		"%s: %s: GROUP TRANSITIONED TO READY, maxbuf = %d\n",
888 			CTCM_FUNTAIL, dev->name, grp->group_max_buflen);
889 
890 	fsm_newstate(grp->fsm, MPCG_STATE_READY);
891 
892 	/* Put up a read on the channel */
893 	ch = priv->channel[CTCM_READ];
894 	ch->pdu_seq = 0;
895 	CTCM_PR_DBGDATA("ctcmpc: %s() ToDCM_pdu_seq= %08x\n" ,
896 			__func__, ch->pdu_seq);
897 
898 	ctcmpc_chx_rxidle(ch->fsm, CTC_EVENT_START, ch);
899 	/* Put the write channel in idle state */
900 	ch = priv->channel[CTCM_WRITE];
901 	if (ch->collect_len > 0) {
902 		spin_lock(&ch->collect_lock);
903 		ctcm_purge_skb_queue(&ch->collect_queue);
904 		ch->collect_len = 0;
905 		spin_unlock(&ch->collect_lock);
906 	}
907 	ctcm_chx_txidle(ch->fsm, CTC_EVENT_START, ch);
908 	ctcm_clear_busy(dev);
909 
910 	if (grp->estconnfunc) {
911 		grp->estconnfunc(grp->port_num, 0,
912 				    grp->group_max_buflen);
913 		grp->estconnfunc = NULL;
914 	} else 	if (grp->allochanfunc)
915 		grp->allochanfunc(grp->port_num, grp->group_max_buflen);
916 
917 	grp->send_qllc_disc = 1;
918 	grp->changed_side = 0;
919 
920 	return;
921 
922 }
923 
924 /*
925  * Increment the MPC Group Active Channel Counts
926  * helper of dev_action (called from channel fsm)
927  */
928 void mpc_channel_action(struct channel *ch, int direction, int action)
929 {
930 	struct net_device  *dev  = ch->netdev;
931 	struct ctcm_priv   *priv = dev->ml_priv;
932 	struct mpc_group   *grp  = priv->mpcg;
933 
934 	if (grp == NULL) {
935 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
936 			"%s(%s): No MPC group",
937 				CTCM_FUNTAIL, dev->name);
938 		return;
939 	}
940 
941 	CTCM_PR_DEBUG("enter %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
942 
943 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
944 		"%s: %i / Grp:%s total_channels=%i, active_channels: "
945 		"read=%i, write=%i\n", __func__, action,
946 		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
947 		grp->active_channels[CTCM_READ],
948 		grp->active_channels[CTCM_WRITE]);
949 
950 	if ((action == MPC_CHANNEL_ADD) && (ch->in_mpcgroup == 0)) {
951 		grp->num_channel_paths++;
952 		grp->active_channels[direction]++;
953 		grp->outstanding_xid2++;
954 		ch->in_mpcgroup = 1;
955 
956 		if (ch->xid_skb != NULL)
957 			dev_kfree_skb_any(ch->xid_skb);
958 
959 		ch->xid_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT,
960 					GFP_ATOMIC | GFP_DMA);
961 		if (ch->xid_skb == NULL) {
962 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
963 				"%s(%s): Couldn't alloc ch xid_skb\n",
964 				CTCM_FUNTAIL, dev->name);
965 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
966 			return;
967 		}
968 		ch->xid_skb_data = ch->xid_skb->data;
969 		ch->xid_th = (struct th_header *)ch->xid_skb->data;
970 		skb_put(ch->xid_skb, TH_HEADER_LENGTH);
971 		ch->xid = (struct xid2 *)skb_tail_pointer(ch->xid_skb);
972 		skb_put(ch->xid_skb, XID2_LENGTH);
973 		ch->xid_id = skb_tail_pointer(ch->xid_skb);
974 		ch->xid_skb->data = ch->xid_skb_data;
975 		skb_reset_tail_pointer(ch->xid_skb);
976 		ch->xid_skb->len = 0;
977 
978 		skb_put_data(ch->xid_skb, grp->xid_skb->data,
979 			     grp->xid_skb->len);
980 
981 		ch->xid->xid2_dlc_type =
982 			((CHANNEL_DIRECTION(ch->flags) == CTCM_READ)
983 				? XID2_READ_SIDE : XID2_WRITE_SIDE);
984 
985 		if (CHANNEL_DIRECTION(ch->flags) == CTCM_WRITE)
986 			ch->xid->xid2_buf_len = 0x00;
987 
988 		ch->xid_skb->data = ch->xid_skb_data;
989 		skb_reset_tail_pointer(ch->xid_skb);
990 		ch->xid_skb->len = 0;
991 
992 		fsm_newstate(ch->fsm, CH_XID0_PENDING);
993 
994 		if ((grp->active_channels[CTCM_READ] > 0) &&
995 		    (grp->active_channels[CTCM_WRITE] > 0) &&
996 			(fsm_getstate(grp->fsm) < MPCG_STATE_XID2INITW)) {
997 			fsm_newstate(grp->fsm, MPCG_STATE_XID2INITW);
998 			CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
999 				"%s: %s: MPC GROUP CHANNELS ACTIVE\n",
1000 						__func__, dev->name);
1001 		}
1002 	} else if ((action == MPC_CHANNEL_REMOVE) &&
1003 			(ch->in_mpcgroup == 1)) {
1004 		ch->in_mpcgroup = 0;
1005 		grp->num_channel_paths--;
1006 		grp->active_channels[direction]--;
1007 
1008 		if (ch->xid_skb != NULL)
1009 			dev_kfree_skb_any(ch->xid_skb);
1010 		ch->xid_skb = NULL;
1011 
1012 		if (grp->channels_terminating)
1013 					goto done;
1014 
1015 		if (((grp->active_channels[CTCM_READ] == 0) &&
1016 					(grp->active_channels[CTCM_WRITE] > 0))
1017 			|| ((grp->active_channels[CTCM_WRITE] == 0) &&
1018 					(grp->active_channels[CTCM_READ] > 0)))
1019 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1020 	}
1021 done:
1022 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
1023 		"exit %s: %i / Grp:%s total_channels=%i, active_channels: "
1024 		"read=%i, write=%i\n", __func__, action,
1025 		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
1026 		grp->active_channels[CTCM_READ],
1027 		grp->active_channels[CTCM_WRITE]);
1028 
1029 	CTCM_PR_DEBUG("exit %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
1030 }
1031 
1032 /**
1033  * Unpack a just received skb and hand it over to
1034  * upper layers.
1035  * special MPC version of unpack_skb.
1036  *
1037  * ch		The channel where this skb has been received.
1038  * pskb		The received skb.
1039  */
1040 static void ctcmpc_unpack_skb(struct channel *ch, struct sk_buff *pskb)
1041 {
1042 	struct net_device *dev	= ch->netdev;
1043 	struct ctcm_priv *priv = dev->ml_priv;
1044 	struct mpc_group *grp = priv->mpcg;
1045 	struct pdu *curr_pdu;
1046 	struct mpcg_info *mpcginfo;
1047 	struct th_header *header = NULL;
1048 	struct th_sweep *sweep = NULL;
1049 	int pdu_last_seen = 0;
1050 	__u32 new_len;
1051 	struct sk_buff *skb;
1052 	int skblen;
1053 	int sendrc = 0;
1054 
1055 	CTCM_PR_DEBUG("ctcmpc enter: %s() %s cp:%i ch:%s\n",
1056 			__func__, dev->name, smp_processor_id(), ch->id);
1057 
1058 	header = (struct th_header *)pskb->data;
1059 	if ((header->th_seg == 0) &&
1060 		(header->th_ch_flag == 0) &&
1061 		(header->th_blk_flag == 0) &&
1062 		(header->th_seq_num == 0))
1063 		/* nothing for us */	goto done;
1064 
1065 	CTCM_PR_DBGDATA("%s: th_header\n", __func__);
1066 	CTCM_D3_DUMP((char *)header, TH_HEADER_LENGTH);
1067 	CTCM_PR_DBGDATA("%s: pskb len: %04x \n", __func__, pskb->len);
1068 
1069 	pskb->dev = dev;
1070 	pskb->ip_summed = CHECKSUM_UNNECESSARY;
1071 	skb_pull(pskb, TH_HEADER_LENGTH);
1072 
1073 	if (likely(header->th_ch_flag == TH_HAS_PDU)) {
1074 		CTCM_PR_DBGDATA("%s: came into th_has_pdu\n", __func__);
1075 		if ((fsm_getstate(grp->fsm) == MPCG_STATE_FLOWC) ||
1076 		   ((fsm_getstate(grp->fsm) == MPCG_STATE_READY) &&
1077 		    (header->th_seq_num != ch->th_seq_num + 1) &&
1078 		    (ch->th_seq_num != 0))) {
1079 			/* This is NOT the next segment		*
1080 			 * we are not the correct race winner	*
1081 			 * go away and let someone else win	*
1082 			 * BUT..this only applies if xid negot	*
1083 			 * is done				*
1084 			*/
1085 			grp->out_of_sequence += 1;
1086 			__skb_push(pskb, TH_HEADER_LENGTH);
1087 			skb_queue_tail(&ch->io_queue, pskb);
1088 			CTCM_PR_DBGDATA("%s: th_seq_num expect:%08x "
1089 					"got:%08x\n", __func__,
1090 				ch->th_seq_num + 1, header->th_seq_num);
1091 
1092 			return;
1093 		}
1094 		grp->out_of_sequence = 0;
1095 		ch->th_seq_num = header->th_seq_num;
1096 
1097 		CTCM_PR_DBGDATA("ctcmpc: %s() FromVTAM_th_seq=%08x\n",
1098 					__func__, ch->th_seq_num);
1099 
1100 		if (unlikely(fsm_getstate(grp->fsm) != MPCG_STATE_READY))
1101 					goto done;
1102 		while ((pskb->len > 0) && !pdu_last_seen) {
1103 			curr_pdu = (struct pdu *)pskb->data;
1104 
1105 			CTCM_PR_DBGDATA("%s: pdu_header\n", __func__);
1106 			CTCM_D3_DUMP((char *)pskb->data, PDU_HEADER_LENGTH);
1107 			CTCM_PR_DBGDATA("%s: pskb len: %04x \n",
1108 						__func__, pskb->len);
1109 
1110 			skb_pull(pskb, PDU_HEADER_LENGTH);
1111 
1112 			if (curr_pdu->pdu_flag & PDU_LAST)
1113 				pdu_last_seen = 1;
1114 			if (curr_pdu->pdu_flag & PDU_CNTL)
1115 				pskb->protocol = htons(ETH_P_SNAP);
1116 			else
1117 				pskb->protocol = htons(ETH_P_SNA_DIX);
1118 
1119 			if ((pskb->len <= 0) || (pskb->len > ch->max_bufsize)) {
1120 				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1121 					"%s(%s): Dropping packet with "
1122 					"illegal siize %d",
1123 					CTCM_FUNTAIL, dev->name, pskb->len);
1124 
1125 				priv->stats.rx_dropped++;
1126 				priv->stats.rx_length_errors++;
1127 					goto done;
1128 			}
1129 			skb_reset_mac_header(pskb);
1130 			new_len = curr_pdu->pdu_offset;
1131 			CTCM_PR_DBGDATA("%s: new_len: %04x \n",
1132 						__func__, new_len);
1133 			if ((new_len == 0) || (new_len > pskb->len)) {
1134 				/* should never happen		    */
1135 				/* pskb len must be hosed...bail out */
1136 				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1137 					"%s(%s): non valid pdu_offset: %04x",
1138 					/* "data may be lost", */
1139 					CTCM_FUNTAIL, dev->name, new_len);
1140 				goto done;
1141 			}
1142 			skb = __dev_alloc_skb(new_len+4, GFP_ATOMIC);
1143 
1144 			if (!skb) {
1145 				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1146 					"%s(%s): MEMORY allocation error",
1147 						CTCM_FUNTAIL, dev->name);
1148 				priv->stats.rx_dropped++;
1149 				fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1150 						goto done;
1151 			}
1152 			skb_put_data(skb, pskb->data, new_len);
1153 
1154 			skb_reset_mac_header(skb);
1155 			skb->dev = pskb->dev;
1156 			skb->protocol = pskb->protocol;
1157 			skb->ip_summed = CHECKSUM_UNNECESSARY;
1158 			*((__u32 *) skb_push(skb, 4)) = ch->pdu_seq;
1159 			ch->pdu_seq++;
1160 
1161 			if (do_debug_data) {
1162 				ctcm_pr_debug("%s: ToDCM_pdu_seq= %08x\n",
1163 						__func__, ch->pdu_seq);
1164 				ctcm_pr_debug("%s: skb:%0lx "
1165 					"skb len: %d \n", __func__,
1166 					(unsigned long)skb, skb->len);
1167 				ctcm_pr_debug("%s: up to 32 bytes "
1168 					"of pdu_data sent\n", __func__);
1169 				ctcmpc_dump32((char *)skb->data, skb->len);
1170 			}
1171 
1172 			skblen = skb->len;
1173 			sendrc = netif_rx(skb);
1174 			priv->stats.rx_packets++;
1175 			priv->stats.rx_bytes += skblen;
1176 			skb_pull(pskb, new_len); /* point to next PDU */
1177 		}
1178 	} else {
1179 		mpcginfo = kmalloc(sizeof(struct mpcg_info), gfp_type());
1180 		if (mpcginfo == NULL)
1181 					goto done;
1182 
1183 		mpcginfo->ch = ch;
1184 		mpcginfo->th = header;
1185 		mpcginfo->skb = pskb;
1186 		CTCM_PR_DEBUG("%s: Not PDU - may be control pkt\n",
1187 					__func__);
1188 		/*  it's a sweep?   */
1189 		sweep = (struct th_sweep *)pskb->data;
1190 		mpcginfo->sweep = sweep;
1191 		if (header->th_ch_flag == TH_SWEEP_REQ)
1192 			mpc_rcvd_sweep_req(mpcginfo);
1193 		else if (header->th_ch_flag == TH_SWEEP_RESP)
1194 			mpc_rcvd_sweep_resp(mpcginfo);
1195 		else if (header->th_blk_flag == TH_DATA_IS_XID) {
1196 			struct xid2 *thisxid = (struct xid2 *)pskb->data;
1197 			skb_pull(pskb, XID2_LENGTH);
1198 			mpcginfo->xid = thisxid;
1199 			fsm_event(grp->fsm, MPCG_EVENT_XID2, mpcginfo);
1200 		} else if (header->th_blk_flag == TH_DISCONTACT)
1201 			fsm_event(grp->fsm, MPCG_EVENT_DISCONC, mpcginfo);
1202 		else if (header->th_seq_num != 0) {
1203 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1204 				"%s(%s): control pkt expected\n",
1205 						CTCM_FUNTAIL, dev->name);
1206 			priv->stats.rx_dropped++;
1207 			/* mpcginfo only used for non-data transfers */
1208 			kfree(mpcginfo);
1209 			if (do_debug_data)
1210 				ctcmpc_dump_skb(pskb, -8);
1211 		}
1212 	}
1213 done:
1214 
1215 	dev_kfree_skb_any(pskb);
1216 	if (sendrc == NET_RX_DROP) {
1217 		dev_warn(&dev->dev,
1218 			"The network backlog for %s is exceeded, "
1219 			"package dropped\n", __func__);
1220 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1221 	}
1222 
1223 	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
1224 			__func__, dev->name, ch, ch->id);
1225 }
1226 
1227 /**
1228  * tasklet helper for mpc's skb unpacking.
1229  *
1230  * ch		The channel to work on.
1231  * Allow flow control back pressure to occur here.
1232  * Throttling back channel can result in excessive
1233  * channel inactivity and system deact of channel
1234  */
1235 void ctcmpc_bh(unsigned long thischan)
1236 {
1237 	struct channel	  *ch	= (struct channel *)thischan;
1238 	struct sk_buff	  *skb;
1239 	struct net_device *dev	= ch->netdev;
1240 	struct ctcm_priv  *priv	= dev->ml_priv;
1241 	struct mpc_group  *grp	= priv->mpcg;
1242 
1243 	CTCM_PR_DEBUG("%s cp:%i enter:  %s() %s\n",
1244 	       dev->name, smp_processor_id(), __func__, ch->id);
1245 	/* caller has requested driver to throttle back */
1246 	while ((fsm_getstate(grp->fsm) != MPCG_STATE_FLOWC) &&
1247 			(skb = skb_dequeue(&ch->io_queue))) {
1248 		ctcmpc_unpack_skb(ch, skb);
1249 		if (grp->out_of_sequence > 20) {
1250 			/* assume data loss has occurred if */
1251 			/* missing seq_num for extended     */
1252 			/* period of time		    */
1253 			grp->out_of_sequence = 0;
1254 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1255 			break;
1256 		}
1257 		if (skb == skb_peek(&ch->io_queue))
1258 			break;
1259 	}
1260 	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
1261 			__func__, dev->name, ch, ch->id);
1262 	return;
1263 }
1264 
1265 /*
1266  *  MPC Group Initializations
1267  */
1268 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv)
1269 {
1270 	struct mpc_group *grp;
1271 
1272 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
1273 			"Enter %s(%p)", CTCM_FUNTAIL, priv);
1274 
1275 	grp = kzalloc(sizeof(struct mpc_group), GFP_KERNEL);
1276 	if (grp == NULL)
1277 		return NULL;
1278 
1279 	grp->fsm = init_fsm("mpcg", mpcg_state_names, mpcg_event_names,
1280 			MPCG_NR_STATES, MPCG_NR_EVENTS, mpcg_fsm,
1281 			mpcg_fsm_len, GFP_KERNEL);
1282 	if (grp->fsm == NULL) {
1283 		kfree(grp);
1284 		return NULL;
1285 	}
1286 
1287 	fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1288 	fsm_settimer(grp->fsm, &grp->timer);
1289 
1290 	grp->xid_skb =
1291 		 __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
1292 	if (grp->xid_skb == NULL) {
1293 		kfree_fsm(grp->fsm);
1294 		kfree(grp);
1295 		return NULL;
1296 	}
1297 	/*  base xid for all channels in group  */
1298 	grp->xid_skb_data = grp->xid_skb->data;
1299 	grp->xid_th = (struct th_header *)grp->xid_skb->data;
1300 	skb_put_data(grp->xid_skb, &thnorm, TH_HEADER_LENGTH);
1301 
1302 	grp->xid = (struct xid2 *)skb_tail_pointer(grp->xid_skb);
1303 	skb_put_data(grp->xid_skb, &init_xid, XID2_LENGTH);
1304 	grp->xid->xid2_adj_id = jiffies | 0xfff00000;
1305 	grp->xid->xid2_sender_id = jiffies;
1306 
1307 	grp->xid_id = skb_tail_pointer(grp->xid_skb);
1308 	skb_put_data(grp->xid_skb, "VTAM", 4);
1309 
1310 	grp->rcvd_xid_skb =
1311 		__dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
1312 	if (grp->rcvd_xid_skb == NULL) {
1313 		kfree_fsm(grp->fsm);
1314 		dev_kfree_skb(grp->xid_skb);
1315 		kfree(grp);
1316 		return NULL;
1317 	}
1318 	grp->rcvd_xid_data = grp->rcvd_xid_skb->data;
1319 	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
1320 	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
1321 	grp->saved_xid2 = NULL;
1322 	priv->xid = grp->xid;
1323 	priv->mpcg = grp;
1324 	return grp;
1325 }
1326 
1327 /*
1328  * The MPC Group Station FSM
1329  */
1330 
1331 /*
1332  * MPC Group Station FSM actions
1333  * CTCM_PROTO_MPC only
1334  */
1335 
1336 /**
1337  * NOP action for statemachines
1338  */
1339 static void mpc_action_nop(fsm_instance *fi, int event, void *arg)
1340 {
1341 }
1342 
1343 /*
1344  * invoked when the device transitions to dev_stopped
1345  * MPC will stop each individual channel if a single XID failure
1346  * occurs, or will intitiate all channels be stopped if a GROUP
1347  * level failure occurs.
1348  */
1349 static void mpc_action_go_inop(fsm_instance *fi, int event, void *arg)
1350 {
1351 	struct net_device  *dev = arg;
1352 	struct ctcm_priv    *priv;
1353 	struct mpc_group *grp;
1354 	struct channel *wch;
1355 
1356 	CTCM_PR_DEBUG("Enter %s: %s\n",	__func__, dev->name);
1357 
1358 	priv  = dev->ml_priv;
1359 	grp =  priv->mpcg;
1360 	grp->flow_off_called = 0;
1361 	fsm_deltimer(&grp->timer);
1362 	if (grp->channels_terminating)
1363 			return;
1364 
1365 	grp->channels_terminating = 1;
1366 	grp->saved_state = fsm_getstate(grp->fsm);
1367 	fsm_newstate(grp->fsm, MPCG_STATE_INOP);
1368 	if (grp->saved_state > MPCG_STATE_XID7INITF)
1369 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1370 			"%s(%s): MPC GROUP INOPERATIVE",
1371 				CTCM_FUNTAIL, dev->name);
1372 	if ((grp->saved_state != MPCG_STATE_RESET) ||
1373 		/* dealloc_channel has been called */
1374 		(grp->port_persist == 0))
1375 		fsm_deltimer(&priv->restart_timer);
1376 
1377 	wch = priv->channel[CTCM_WRITE];
1378 
1379 	switch (grp->saved_state) {
1380 	case MPCG_STATE_RESET:
1381 	case MPCG_STATE_INOP:
1382 	case MPCG_STATE_XID2INITW:
1383 	case MPCG_STATE_XID0IOWAIT:
1384 	case MPCG_STATE_XID2INITX:
1385 	case MPCG_STATE_XID7INITW:
1386 	case MPCG_STATE_XID7INITX:
1387 	case MPCG_STATE_XID0IOWAIX:
1388 	case MPCG_STATE_XID7INITI:
1389 	case MPCG_STATE_XID7INITZ:
1390 	case MPCG_STATE_XID7INITF:
1391 		break;
1392 	case MPCG_STATE_FLOWC:
1393 	case MPCG_STATE_READY:
1394 	default:
1395 		tasklet_hi_schedule(&wch->ch_disc_tasklet);
1396 	}
1397 
1398 	grp->xid2_tgnum = 0;
1399 	grp->group_max_buflen = 0;  /*min of all received */
1400 	grp->outstanding_xid2 = 0;
1401 	grp->outstanding_xid7 = 0;
1402 	grp->outstanding_xid7_p2 = 0;
1403 	grp->saved_xid2 = NULL;
1404 	grp->xidnogood = 0;
1405 	grp->changed_side = 0;
1406 
1407 	grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
1408 	skb_reset_tail_pointer(grp->rcvd_xid_skb);
1409 	grp->rcvd_xid_skb->len = 0;
1410 	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
1411 	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
1412 
1413 	if (grp->send_qllc_disc == 1) {
1414 		grp->send_qllc_disc = 0;
1415 		mpc_send_qllc_discontact(dev);
1416 	}
1417 
1418 	/* DO NOT issue DEV_EVENT_STOP directly out of this code */
1419 	/* This can result in INOP of VTAM PU due to halting of  */
1420 	/* outstanding IO which causes a sense to be returned	 */
1421 	/* Only about 3 senses are allowed and then IOS/VTAM will*/
1422 	/* become unreachable without manual intervention	 */
1423 	if ((grp->port_persist == 1) || (grp->alloc_called)) {
1424 		grp->alloc_called = 0;
1425 		fsm_deltimer(&priv->restart_timer);
1426 		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_RESTART, dev);
1427 		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1428 		if (grp->saved_state > MPCG_STATE_XID7INITF)
1429 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
1430 				"%s(%s): MPC GROUP RECOVERY SCHEDULED",
1431 					CTCM_FUNTAIL, dev->name);
1432 	} else {
1433 		fsm_deltimer(&priv->restart_timer);
1434 		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_STOP, dev);
1435 		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1436 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
1437 			"%s(%s): NO MPC GROUP RECOVERY ATTEMPTED",
1438 						CTCM_FUNTAIL, dev->name);
1439 	}
1440 }
1441 
1442 /**
1443  * Handle mpc group  action timeout.
1444  * MPC Group Station FSM action
1445  * CTCM_PROTO_MPC only
1446  *
1447  * fi		An instance of an mpc_group fsm.
1448  * event	The event, just happened.
1449  * arg		Generic pointer, casted from net_device * upon call.
1450  */
1451 static void mpc_action_timeout(fsm_instance *fi, int event, void *arg)
1452 {
1453 	struct net_device *dev = arg;
1454 	struct ctcm_priv *priv;
1455 	struct mpc_group *grp;
1456 	struct channel *wch;
1457 	struct channel *rch;
1458 
1459 	priv = dev->ml_priv;
1460 	grp = priv->mpcg;
1461 	wch = priv->channel[CTCM_WRITE];
1462 	rch = priv->channel[CTCM_READ];
1463 
1464 	switch (fsm_getstate(grp->fsm)) {
1465 	case MPCG_STATE_XID2INITW:
1466 		/* Unless there is outstanding IO on the  */
1467 		/* channel just return and wait for ATTN  */
1468 		/* interrupt to begin XID negotiations	  */
1469 		if ((fsm_getstate(rch->fsm) == CH_XID0_PENDING) &&
1470 		   (fsm_getstate(wch->fsm) == CH_XID0_PENDING))
1471 			break;
1472 	default:
1473 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1474 	}
1475 
1476 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
1477 			"%s: dev=%s exit",
1478 			CTCM_FUNTAIL, dev->name);
1479 	return;
1480 }
1481 
1482 /*
1483  * MPC Group Station FSM action
1484  * CTCM_PROTO_MPC only
1485  */
1486 void mpc_action_discontact(fsm_instance *fi, int event, void *arg)
1487 {
1488 	struct mpcg_info   *mpcginfo   = arg;
1489 	struct channel	   *ch	       = mpcginfo->ch;
1490 	struct net_device  *dev;
1491 	struct ctcm_priv   *priv;
1492 	struct mpc_group   *grp;
1493 
1494 	if (ch) {
1495 		dev = ch->netdev;
1496 		if (dev) {
1497 			priv = dev->ml_priv;
1498 			if (priv) {
1499 				CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1500 					"%s: %s: %s\n",
1501 					CTCM_FUNTAIL, dev->name, ch->id);
1502 				grp = priv->mpcg;
1503 				grp->send_qllc_disc = 1;
1504 				fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1505 			}
1506 		}
1507 	}
1508 
1509 	return;
1510 }
1511 
1512 /*
1513  * MPC Group Station - not part of FSM
1514  * CTCM_PROTO_MPC only
1515  * called from add_channel in ctcm_main.c
1516  */
1517 void mpc_action_send_discontact(unsigned long thischan)
1518 {
1519 	int rc;
1520 	struct channel	*ch = (struct channel *)thischan;
1521 	unsigned long	saveflags = 0;
1522 
1523 	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1524 	rc = ccw_device_start(ch->cdev, &ch->ccw[15],
1525 					(unsigned long)ch, 0xff, 0);
1526 	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1527 
1528 	if (rc != 0) {
1529 		ctcm_ccw_check_rc(ch, rc, (char *)__func__);
1530 	}
1531 
1532 	return;
1533 }
1534 
1535 
1536 /*
1537  * helper function of mpc FSM
1538  * CTCM_PROTO_MPC only
1539  * mpc_action_rcvd_xid7
1540 */
1541 static int mpc_validate_xid(struct mpcg_info *mpcginfo)
1542 {
1543 	struct channel	   *ch	 = mpcginfo->ch;
1544 	struct net_device  *dev  = ch->netdev;
1545 	struct ctcm_priv   *priv = dev->ml_priv;
1546 	struct mpc_group   *grp  = priv->mpcg;
1547 	struct xid2	   *xid  = mpcginfo->xid;
1548 	int	rc	 = 0;
1549 	__u64	our_id   = 0;
1550 	__u64   their_id = 0;
1551 	int	len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1552 
1553 	CTCM_PR_DEBUG("Enter %s: xid=%p\n", __func__, xid);
1554 
1555 	if (xid == NULL) {
1556 		rc = 1;
1557 		/* XID REJECTED: xid == NULL */
1558 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1559 			"%s(%s): xid = NULL",
1560 				CTCM_FUNTAIL, ch->id);
1561 			goto done;
1562 	}
1563 
1564 	CTCM_D3_DUMP((char *)xid, XID2_LENGTH);
1565 
1566 	/*the received direction should be the opposite of ours  */
1567 	if (((CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ? XID2_WRITE_SIDE :
1568 				XID2_READ_SIDE) != xid->xid2_dlc_type) {
1569 		rc = 2;
1570 		/* XID REJECTED: r/w channel pairing mismatch */
1571 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1572 			"%s(%s): r/w channel pairing mismatch",
1573 				CTCM_FUNTAIL, ch->id);
1574 			goto done;
1575 	}
1576 
1577 	if (xid->xid2_dlc_type == XID2_READ_SIDE) {
1578 		CTCM_PR_DEBUG("%s: grpmaxbuf:%d xid2buflen:%d\n", __func__,
1579 				grp->group_max_buflen, xid->xid2_buf_len);
1580 
1581 		if (grp->group_max_buflen == 0 || grp->group_max_buflen >
1582 						xid->xid2_buf_len - len)
1583 			grp->group_max_buflen = xid->xid2_buf_len - len;
1584 	}
1585 
1586 	if (grp->saved_xid2 == NULL) {
1587 		grp->saved_xid2 =
1588 			(struct xid2 *)skb_tail_pointer(grp->rcvd_xid_skb);
1589 
1590 		skb_put_data(grp->rcvd_xid_skb, xid, XID2_LENGTH);
1591 		grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
1592 
1593 		skb_reset_tail_pointer(grp->rcvd_xid_skb);
1594 		grp->rcvd_xid_skb->len = 0;
1595 
1596 		/* convert two 32 bit numbers into 1 64 bit for id compare */
1597 		our_id = (__u64)priv->xid->xid2_adj_id;
1598 		our_id = our_id << 32;
1599 		our_id = our_id + priv->xid->xid2_sender_id;
1600 		their_id = (__u64)xid->xid2_adj_id;
1601 		their_id = their_id << 32;
1602 		their_id = their_id + xid->xid2_sender_id;
1603 		/* lower id assume the xside role */
1604 		if (our_id < their_id) {
1605 			grp->roll = XSIDE;
1606 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1607 				"%s(%s): WE HAVE LOW ID - TAKE XSIDE",
1608 					CTCM_FUNTAIL, ch->id);
1609 		} else {
1610 			grp->roll = YSIDE;
1611 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1612 				"%s(%s): WE HAVE HIGH ID - TAKE YSIDE",
1613 					CTCM_FUNTAIL, ch->id);
1614 		}
1615 
1616 	} else {
1617 		if (xid->xid2_flag4 != grp->saved_xid2->xid2_flag4) {
1618 			rc = 3;
1619 			/* XID REJECTED: xid flag byte4 mismatch */
1620 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1621 				"%s(%s): xid flag byte4 mismatch",
1622 					CTCM_FUNTAIL, ch->id);
1623 		}
1624 		if (xid->xid2_flag2 == 0x40) {
1625 			rc = 4;
1626 			/* XID REJECTED - xid NOGOOD */
1627 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1628 				"%s(%s): xid NOGOOD",
1629 					CTCM_FUNTAIL, ch->id);
1630 		}
1631 		if (xid->xid2_adj_id != grp->saved_xid2->xid2_adj_id) {
1632 			rc = 5;
1633 			/* XID REJECTED - Adjacent Station ID Mismatch */
1634 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1635 				"%s(%s): Adjacent Station ID Mismatch",
1636 					CTCM_FUNTAIL, ch->id);
1637 		}
1638 		if (xid->xid2_sender_id != grp->saved_xid2->xid2_sender_id) {
1639 			rc = 6;
1640 			/* XID REJECTED - Sender Address Mismatch */
1641 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1642 				"%s(%s): Sender Address Mismatch",
1643 					CTCM_FUNTAIL, ch->id);
1644 		}
1645 	}
1646 done:
1647 	if (rc) {
1648 		dev_warn(&dev->dev,
1649 			"The XID used in the MPC protocol is not valid, "
1650 			"rc = %d\n", rc);
1651 		priv->xid->xid2_flag2 = 0x40;
1652 		grp->saved_xid2->xid2_flag2 = 0x40;
1653 	}
1654 
1655 	return rc;
1656 }
1657 
1658 /*
1659  * MPC Group Station FSM action
1660  * CTCM_PROTO_MPC only
1661  */
1662 static void mpc_action_side_xid(fsm_instance *fsm, void *arg, int side)
1663 {
1664 	struct channel *ch = arg;
1665 	int rc = 0;
1666 	int gotlock = 0;
1667 	unsigned long saveflags = 0;	/* avoids compiler warning with
1668 					   spin_unlock_irqrestore */
1669 
1670 	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
1671 			__func__, smp_processor_id(), ch, ch->id);
1672 
1673 	if (ctcm_checkalloc_buffer(ch))
1674 					goto done;
1675 
1676 	/*
1677 	 * skb data-buffer referencing:
1678 	 */
1679 	ch->trans_skb->data = ch->trans_skb_data;
1680 	skb_reset_tail_pointer(ch->trans_skb);
1681 	ch->trans_skb->len = 0;
1682 	/* result of the previous 3 statements is NOT always
1683 	 * already set after ctcm_checkalloc_buffer
1684 	 * because of possible reuse of the trans_skb
1685 	 */
1686 	memset(ch->trans_skb->data, 0, 16);
1687 	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
1688 	/* check is main purpose here: */
1689 	skb_put(ch->trans_skb, TH_HEADER_LENGTH);
1690 	ch->rcvd_xid = (struct xid2 *)skb_tail_pointer(ch->trans_skb);
1691 	/* check is main purpose here: */
1692 	skb_put(ch->trans_skb, XID2_LENGTH);
1693 	ch->rcvd_xid_id = skb_tail_pointer(ch->trans_skb);
1694 	/* cleanup back to startpoint */
1695 	ch->trans_skb->data = ch->trans_skb_data;
1696 	skb_reset_tail_pointer(ch->trans_skb);
1697 	ch->trans_skb->len = 0;
1698 
1699 	/* non-checking rewrite of above skb data-buffer referencing: */
1700 	/*
1701 	memset(ch->trans_skb->data, 0, 16);
1702 	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
1703 	ch->rcvd_xid = (struct xid2 *)(ch->trans_skb_data + TH_HEADER_LENGTH);
1704 	ch->rcvd_xid_id = ch->trans_skb_data + TH_HEADER_LENGTH + XID2_LENGTH;
1705 	 */
1706 
1707 	ch->ccw[8].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1708 	ch->ccw[8].count	= 0;
1709 	ch->ccw[8].cda		= 0x00;
1710 
1711 	if (!(ch->xid_th && ch->xid && ch->xid_id))
1712 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_INFO,
1713 			"%s(%s): xid_th=%p, xid=%p, xid_id=%p",
1714 			CTCM_FUNTAIL, ch->id, ch->xid_th, ch->xid, ch->xid_id);
1715 
1716 	if (side == XSIDE) {
1717 		/* mpc_action_xside_xid */
1718 		if (ch->xid_th == NULL)
1719 				goto done;
1720 		ch->ccw[9].cmd_code	= CCW_CMD_WRITE;
1721 		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1722 		ch->ccw[9].count	= TH_HEADER_LENGTH;
1723 		ch->ccw[9].cda		= virt_to_phys(ch->xid_th);
1724 
1725 		if (ch->xid == NULL)
1726 				goto done;
1727 		ch->ccw[10].cmd_code	= CCW_CMD_WRITE;
1728 		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1729 		ch->ccw[10].count	= XID2_LENGTH;
1730 		ch->ccw[10].cda		= virt_to_phys(ch->xid);
1731 
1732 		ch->ccw[11].cmd_code	= CCW_CMD_READ;
1733 		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1734 		ch->ccw[11].count	= TH_HEADER_LENGTH;
1735 		ch->ccw[11].cda		= virt_to_phys(ch->rcvd_xid_th);
1736 
1737 		ch->ccw[12].cmd_code	= CCW_CMD_READ;
1738 		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1739 		ch->ccw[12].count	= XID2_LENGTH;
1740 		ch->ccw[12].cda		= virt_to_phys(ch->rcvd_xid);
1741 
1742 		ch->ccw[13].cmd_code	= CCW_CMD_READ;
1743 		ch->ccw[13].cda		= virt_to_phys(ch->rcvd_xid_id);
1744 
1745 	} else { /* side == YSIDE : mpc_action_yside_xid */
1746 		ch->ccw[9].cmd_code	= CCW_CMD_READ;
1747 		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1748 		ch->ccw[9].count	= TH_HEADER_LENGTH;
1749 		ch->ccw[9].cda		= virt_to_phys(ch->rcvd_xid_th);
1750 
1751 		ch->ccw[10].cmd_code	= CCW_CMD_READ;
1752 		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1753 		ch->ccw[10].count	= XID2_LENGTH;
1754 		ch->ccw[10].cda		= virt_to_phys(ch->rcvd_xid);
1755 
1756 		if (ch->xid_th == NULL)
1757 				goto done;
1758 		ch->ccw[11].cmd_code	= CCW_CMD_WRITE;
1759 		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1760 		ch->ccw[11].count	= TH_HEADER_LENGTH;
1761 		ch->ccw[11].cda		= virt_to_phys(ch->xid_th);
1762 
1763 		if (ch->xid == NULL)
1764 				goto done;
1765 		ch->ccw[12].cmd_code	= CCW_CMD_WRITE;
1766 		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1767 		ch->ccw[12].count	= XID2_LENGTH;
1768 		ch->ccw[12].cda		= virt_to_phys(ch->xid);
1769 
1770 		if (ch->xid_id == NULL)
1771 				goto done;
1772 		ch->ccw[13].cmd_code	= CCW_CMD_WRITE;
1773 		ch->ccw[13].cda		= virt_to_phys(ch->xid_id);
1774 
1775 	}
1776 	ch->ccw[13].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1777 	ch->ccw[13].count	= 4;
1778 
1779 	ch->ccw[14].cmd_code	= CCW_CMD_NOOP;
1780 	ch->ccw[14].flags	= CCW_FLAG_SLI;
1781 	ch->ccw[14].count	= 0;
1782 	ch->ccw[14].cda		= 0;
1783 
1784 	CTCM_CCW_DUMP((char *)&ch->ccw[8], sizeof(struct ccw1) * 7);
1785 	CTCM_D3_DUMP((char *)ch->xid_th, TH_HEADER_LENGTH);
1786 	CTCM_D3_DUMP((char *)ch->xid, XID2_LENGTH);
1787 	CTCM_D3_DUMP((char *)ch->xid_id, 4);
1788 
1789 	if (!in_irq()) {
1790 			 /* Such conditional locking is a known problem for
1791 			  * sparse because its static undeterministic.
1792 			  * Warnings should be ignored here. */
1793 		spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1794 		gotlock = 1;
1795 	}
1796 
1797 	fsm_addtimer(&ch->timer, 5000 , CTC_EVENT_TIMER, ch);
1798 	rc = ccw_device_start(ch->cdev, &ch->ccw[8],
1799 				(unsigned long)ch, 0xff, 0);
1800 
1801 	if (gotlock)	/* see remark above about conditional locking */
1802 		spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1803 
1804 	if (rc != 0) {
1805 		ctcm_ccw_check_rc(ch, rc,
1806 				(side == XSIDE) ? "x-side XID" : "y-side XID");
1807 	}
1808 
1809 done:
1810 	CTCM_PR_DEBUG("Exit %s: ch=0x%p id=%s\n",
1811 				__func__, ch, ch->id);
1812 	return;
1813 
1814 }
1815 
1816 /*
1817  * MPC Group Station FSM action
1818  * CTCM_PROTO_MPC only
1819  */
1820 static void mpc_action_xside_xid(fsm_instance *fsm, int event, void *arg)
1821 {
1822 	mpc_action_side_xid(fsm, arg, XSIDE);
1823 }
1824 
1825 /*
1826  * MPC Group Station FSM action
1827  * CTCM_PROTO_MPC only
1828  */
1829 static void mpc_action_yside_xid(fsm_instance *fsm, int event, void *arg)
1830 {
1831 	mpc_action_side_xid(fsm, arg, YSIDE);
1832 }
1833 
1834 /*
1835  * MPC Group Station FSM action
1836  * CTCM_PROTO_MPC only
1837  */
1838 static void mpc_action_doxid0(fsm_instance *fsm, int event, void *arg)
1839 {
1840 	struct channel	   *ch   = arg;
1841 	struct net_device  *dev  = ch->netdev;
1842 	struct ctcm_priv   *priv = dev->ml_priv;
1843 	struct mpc_group   *grp  = priv->mpcg;
1844 
1845 	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
1846 			__func__, smp_processor_id(), ch, ch->id);
1847 
1848 	if (ch->xid == NULL) {
1849 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1850 			"%s(%s): ch->xid == NULL",
1851 				CTCM_FUNTAIL, dev->name);
1852 		return;
1853 	}
1854 
1855 	fsm_newstate(ch->fsm, CH_XID0_INPROGRESS);
1856 
1857 	ch->xid->xid2_option =	XID2_0;
1858 
1859 	switch (fsm_getstate(grp->fsm)) {
1860 	case MPCG_STATE_XID2INITW:
1861 	case MPCG_STATE_XID2INITX:
1862 		ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1863 		break;
1864 	case MPCG_STATE_XID0IOWAIT:
1865 	case MPCG_STATE_XID0IOWAIX:
1866 		ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1867 		break;
1868 	}
1869 
1870 	fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
1871 
1872 	return;
1873 }
1874 
1875 /*
1876  * MPC Group Station FSM action
1877  * CTCM_PROTO_MPC only
1878 */
1879 static void mpc_action_doxid7(fsm_instance *fsm, int event, void *arg)
1880 {
1881 	struct net_device *dev = arg;
1882 	struct ctcm_priv  *priv = dev->ml_priv;
1883 	struct mpc_group  *grp  = NULL;
1884 	int direction;
1885 	int send = 0;
1886 
1887 	if (priv)
1888 		grp = priv->mpcg;
1889 	if (grp == NULL)
1890 		return;
1891 
1892 	for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1893 		struct channel *ch = priv->channel[direction];
1894 		struct xid2 *thisxid = ch->xid;
1895 		ch->xid_skb->data = ch->xid_skb_data;
1896 		skb_reset_tail_pointer(ch->xid_skb);
1897 		ch->xid_skb->len = 0;
1898 		thisxid->xid2_option = XID2_7;
1899 		send = 0;
1900 
1901 		/* xid7 phase 1 */
1902 		if (grp->outstanding_xid7_p2 > 0) {
1903 			if (grp->roll == YSIDE) {
1904 				if (fsm_getstate(ch->fsm) == CH_XID7_PENDING1) {
1905 					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
1906 					ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1907 					skb_put_data(ch->xid_skb, &thdummy,
1908 						     TH_HEADER_LENGTH);
1909 					send = 1;
1910 				}
1911 			} else if (fsm_getstate(ch->fsm) < CH_XID7_PENDING2) {
1912 					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
1913 					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1914 					skb_put_data(ch->xid_skb, &thnorm,
1915 						     TH_HEADER_LENGTH);
1916 					send = 1;
1917 			}
1918 		} else {
1919 			/* xid7 phase 2 */
1920 			if (grp->roll == YSIDE) {
1921 				if (fsm_getstate(ch->fsm) < CH_XID7_PENDING4) {
1922 					fsm_newstate(ch->fsm, CH_XID7_PENDING4);
1923 					skb_put_data(ch->xid_skb, &thnorm,
1924 						     TH_HEADER_LENGTH);
1925 					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1926 					send = 1;
1927 				}
1928 			} else if (fsm_getstate(ch->fsm) == CH_XID7_PENDING3) {
1929 				fsm_newstate(ch->fsm, CH_XID7_PENDING4);
1930 				ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1931 				skb_put_data(ch->xid_skb, &thdummy,
1932 					     TH_HEADER_LENGTH);
1933 				send = 1;
1934 			}
1935 		}
1936 
1937 		if (send)
1938 			fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
1939 	}
1940 
1941 	return;
1942 }
1943 
1944 /*
1945  * MPC Group Station FSM action
1946  * CTCM_PROTO_MPC only
1947  */
1948 static void mpc_action_rcvd_xid0(fsm_instance *fsm, int event, void *arg)
1949 {
1950 
1951 	struct mpcg_info   *mpcginfo  = arg;
1952 	struct channel	   *ch   = mpcginfo->ch;
1953 	struct net_device  *dev  = ch->netdev;
1954 	struct ctcm_priv   *priv = dev->ml_priv;
1955 	struct mpc_group   *grp  = priv->mpcg;
1956 
1957 	CTCM_PR_DEBUG("%s: ch-id:%s xid2:%i xid7:%i xidt_p2:%i \n",
1958 			__func__, ch->id, grp->outstanding_xid2,
1959 			grp->outstanding_xid7, grp->outstanding_xid7_p2);
1960 
1961 	if (fsm_getstate(ch->fsm) < CH_XID7_PENDING)
1962 		fsm_newstate(ch->fsm, CH_XID7_PENDING);
1963 
1964 	grp->outstanding_xid2--;
1965 	grp->outstanding_xid7++;
1966 	grp->outstanding_xid7_p2++;
1967 
1968 	/* must change state before validating xid to */
1969 	/* properly handle interim interrupts received*/
1970 	switch (fsm_getstate(grp->fsm)) {
1971 	case MPCG_STATE_XID2INITW:
1972 		fsm_newstate(grp->fsm, MPCG_STATE_XID2INITX);
1973 		mpc_validate_xid(mpcginfo);
1974 		break;
1975 	case MPCG_STATE_XID0IOWAIT:
1976 		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIX);
1977 		mpc_validate_xid(mpcginfo);
1978 		break;
1979 	case MPCG_STATE_XID2INITX:
1980 		if (grp->outstanding_xid2 == 0) {
1981 			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITW);
1982 			mpc_validate_xid(mpcginfo);
1983 			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
1984 		}
1985 		break;
1986 	case MPCG_STATE_XID0IOWAIX:
1987 		if (grp->outstanding_xid2 == 0) {
1988 			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITI);
1989 			mpc_validate_xid(mpcginfo);
1990 			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
1991 		}
1992 		break;
1993 	}
1994 	kfree(mpcginfo);
1995 
1996 	CTCM_PR_DEBUG("ctcmpc:%s() %s xid2:%i xid7:%i xidt_p2:%i \n",
1997 		__func__, ch->id, grp->outstanding_xid2,
1998 		grp->outstanding_xid7, grp->outstanding_xid7_p2);
1999 	CTCM_PR_DEBUG("ctcmpc:%s() %s grpstate: %s chanstate: %s \n",
2000 		__func__, ch->id,
2001 		fsm_getstate_str(grp->fsm), fsm_getstate_str(ch->fsm));
2002 	return;
2003 
2004 }
2005 
2006 
2007 /*
2008  * MPC Group Station FSM action
2009  * CTCM_PROTO_MPC only
2010  */
2011 static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg)
2012 {
2013 	struct mpcg_info   *mpcginfo   = arg;
2014 	struct channel	   *ch	       = mpcginfo->ch;
2015 	struct net_device  *dev        = ch->netdev;
2016 	struct ctcm_priv   *priv    = dev->ml_priv;
2017 	struct mpc_group   *grp     = priv->mpcg;
2018 
2019 	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
2020 		__func__, smp_processor_id(), ch, ch->id);
2021 	CTCM_PR_DEBUG("%s: outstanding_xid7: %i, outstanding_xid7_p2: %i\n",
2022 		__func__, grp->outstanding_xid7, grp->outstanding_xid7_p2);
2023 
2024 	grp->outstanding_xid7--;
2025 	ch->xid_skb->data = ch->xid_skb_data;
2026 	skb_reset_tail_pointer(ch->xid_skb);
2027 	ch->xid_skb->len = 0;
2028 
2029 	switch (fsm_getstate(grp->fsm)) {
2030 	case MPCG_STATE_XID7INITI:
2031 		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITZ);
2032 		mpc_validate_xid(mpcginfo);
2033 		break;
2034 	case MPCG_STATE_XID7INITW:
2035 		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITX);
2036 		mpc_validate_xid(mpcginfo);
2037 		break;
2038 	case MPCG_STATE_XID7INITZ:
2039 	case MPCG_STATE_XID7INITX:
2040 		if (grp->outstanding_xid7 == 0) {
2041 			if (grp->outstanding_xid7_p2 > 0) {
2042 				grp->outstanding_xid7 =
2043 					grp->outstanding_xid7_p2;
2044 				grp->outstanding_xid7_p2 = 0;
2045 			} else
2046 				fsm_newstate(grp->fsm, MPCG_STATE_XID7INITF);
2047 
2048 			mpc_validate_xid(mpcginfo);
2049 			fsm_event(grp->fsm, MPCG_EVENT_XID7DONE, dev);
2050 			break;
2051 		}
2052 		mpc_validate_xid(mpcginfo);
2053 		break;
2054 	}
2055 	kfree(mpcginfo);
2056 	return;
2057 }
2058 
2059 /*
2060  * mpc_action helper of an MPC Group Station FSM action
2061  * CTCM_PROTO_MPC only
2062  */
2063 static int mpc_send_qllc_discontact(struct net_device *dev)
2064 {
2065 	__u32	new_len	= 0;
2066 	struct sk_buff   *skb;
2067 	struct qllc      *qllcptr;
2068 	struct ctcm_priv *priv = dev->ml_priv;
2069 	struct mpc_group *grp = priv->mpcg;
2070 
2071 	CTCM_PR_DEBUG("%s: GROUP STATE: %s\n",
2072 		__func__, mpcg_state_names[grp->saved_state]);
2073 
2074 	switch (grp->saved_state) {
2075 	/*
2076 	 * establish conn callback function is
2077 	 * preferred method to report failure
2078 	 */
2079 	case MPCG_STATE_XID0IOWAIT:
2080 	case MPCG_STATE_XID0IOWAIX:
2081 	case MPCG_STATE_XID7INITI:
2082 	case MPCG_STATE_XID7INITZ:
2083 	case MPCG_STATE_XID2INITW:
2084 	case MPCG_STATE_XID2INITX:
2085 	case MPCG_STATE_XID7INITW:
2086 	case MPCG_STATE_XID7INITX:
2087 		if (grp->estconnfunc) {
2088 			grp->estconnfunc(grp->port_num, -1, 0);
2089 			grp->estconnfunc = NULL;
2090 			break;
2091 		}
2092 	case MPCG_STATE_FLOWC:
2093 	case MPCG_STATE_READY:
2094 		grp->send_qllc_disc = 2;
2095 		new_len = sizeof(struct qllc);
2096 		qllcptr = kzalloc(new_len, gfp_type() | GFP_DMA);
2097 		if (qllcptr == NULL) {
2098 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2099 				"%s(%s): qllcptr allocation error",
2100 						CTCM_FUNTAIL, dev->name);
2101 			return -ENOMEM;
2102 		}
2103 
2104 		qllcptr->qllc_address = 0xcc;
2105 		qllcptr->qllc_commands = 0x03;
2106 
2107 		skb = __dev_alloc_skb(new_len, GFP_ATOMIC);
2108 
2109 		if (skb == NULL) {
2110 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2111 				"%s(%s): skb allocation error",
2112 						CTCM_FUNTAIL, dev->name);
2113 			priv->stats.rx_dropped++;
2114 			kfree(qllcptr);
2115 			return -ENOMEM;
2116 		}
2117 
2118 		skb_put_data(skb, qllcptr, new_len);
2119 		kfree(qllcptr);
2120 
2121 		if (skb_headroom(skb) < 4) {
2122 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2123 				"%s(%s): skb_headroom error",
2124 						CTCM_FUNTAIL, dev->name);
2125 			dev_kfree_skb_any(skb);
2126 			return -ENOMEM;
2127 		}
2128 
2129 		*((__u32 *)skb_push(skb, 4)) =
2130 			priv->channel[CTCM_READ]->pdu_seq;
2131 		priv->channel[CTCM_READ]->pdu_seq++;
2132 		CTCM_PR_DBGDATA("ctcmpc: %s ToDCM_pdu_seq= %08x\n",
2133 				__func__, priv->channel[CTCM_READ]->pdu_seq);
2134 
2135 		/* receipt of CC03 resets anticipated sequence number on
2136 		      receiving side */
2137 		priv->channel[CTCM_READ]->pdu_seq = 0x00;
2138 		skb_reset_mac_header(skb);
2139 		skb->dev = dev;
2140 		skb->protocol = htons(ETH_P_SNAP);
2141 		skb->ip_summed = CHECKSUM_UNNECESSARY;
2142 
2143 		CTCM_D3_DUMP(skb->data, (sizeof(struct qllc) + 4));
2144 
2145 		netif_rx(skb);
2146 		break;
2147 	default:
2148 		break;
2149 
2150 	}
2151 
2152 	return 0;
2153 }
2154 /* --- This is the END my friend --- */
2155 
2156