xref: /linux/drivers/s390/net/ctcm_mpc.c (revision bc46b7cbc58c4cb562b6a45a1fbc7b8e7b23df58)
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/export.h>
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <linux/slab.h>
29 #include <linux/errno.h>
30 #include <linux/types.h>
31 #include <linux/interrupt.h>
32 #include <linux/timer.h>
33 #include <linux/sched.h>
34 
35 #include <linux/signal.h>
36 #include <linux/string.h>
37 #include <linux/proc_fs.h>
38 
39 #include <linux/ip.h>
40 #include <linux/if_arp.h>
41 #include <linux/tcp.h>
42 #include <linux/skbuff.h>
43 #include <linux/ctype.h>
44 #include <linux/netdevice.h>
45 #include <net/dst.h>
46 
47 #include <linux/io.h>
48 #include <linux/bitops.h>
49 #include <linux/uaccess.h>
50 #include <linux/wait.h>
51 #include <linux/moduleparam.h>
52 #include <asm/ccwdev.h>
53 #include <asm/ccwgroup.h>
54 #include <asm/idals.h>
55 
56 #include "ctcm_main.h"
57 #include "ctcm_mpc.h"
58 #include "ctcm_fsms.h"
59 
60 static const struct xid2 init_xid = {
61 	.xid2_type_id	=	XID_FM2,
62 	.xid2_len	=	0x45,
63 	.xid2_adj_id	=	0,
64 	.xid2_rlen	=	0x31,
65 	.xid2_resv1	=	0,
66 	.xid2_flag1	=	0,
67 	.xid2_fmtt	=	0,
68 	.xid2_flag4	=	0x80,
69 	.xid2_resv2	=	0,
70 	.xid2_tgnum	=	0,
71 	.xid2_sender_id	=	0,
72 	.xid2_flag2	=	0,
73 	.xid2_option	=	XID2_0,
74 	.xid2_resv3	=	"\x00",
75 	.xid2_resv4	=	0,
76 	.xid2_dlc_type	=	XID2_READ_SIDE,
77 	.xid2_resv5	=	0,
78 	.xid2_mpc_flag	=	0,
79 	.xid2_resv6	=	0,
80 	.xid2_buf_len	=	(MPC_BUFSIZE_DEFAULT - 35),
81 };
82 
83 static const struct th_header thnorm = {
84 	.th_seg		=	0x00,
85 	.th_ch_flag	=	TH_IS_XID,
86 	.th_blk_flag	=	TH_DATA_IS_XID,
87 	.th_is_xid	=	0x01,
88 	.th_seq_num	=	0x00000000,
89 };
90 
91 static const struct th_header thdummy = {
92 	.th_seg		=	0x00,
93 	.th_ch_flag	=	0x00,
94 	.th_blk_flag	=	TH_DATA_IS_XID,
95 	.th_is_xid	=	0x01,
96 	.th_seq_num	=	0x00000000,
97 };
98 
99 /*
100  * Definition of one MPC group
101  */
102 
103 /*
104  * Compatibility macros for busy handling
105  * of network devices.
106  */
107 
108 static void ctcmpc_unpack_skb(struct channel *ch, struct sk_buff *pskb);
109 
110 /*
111  * MPC Group state machine actions (static prototypes)
112  */
113 static void mpc_action_nop(fsm_instance *fsm, int event, void *arg);
114 static void mpc_action_go_ready(fsm_instance *fsm, int event, void *arg);
115 static void mpc_action_go_inop(fsm_instance *fi, int event, void *arg);
116 static void mpc_action_timeout(fsm_instance *fi, int event, void *arg);
117 static int  mpc_validate_xid(struct mpcg_info *mpcginfo);
118 static void mpc_action_yside_xid(fsm_instance *fsm, int event, void *arg);
119 static void mpc_action_doxid0(fsm_instance *fsm, int event, void *arg);
120 static void mpc_action_doxid7(fsm_instance *fsm, int event, void *arg);
121 static void mpc_action_xside_xid(fsm_instance *fsm, int event, void *arg);
122 static void mpc_action_rcvd_xid0(fsm_instance *fsm, int event, void *arg);
123 static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg);
124 
125 #ifdef DEBUGDATA
126 /*-------------------------------------------------------------------*
127 * Dump buffer format						     *
128 *								     *
129 *--------------------------------------------------------------------*/
ctcmpc_dumpit(char * buf,int len)130 void ctcmpc_dumpit(char *buf, int len)
131 {
132 	__u32	ct, sw, rm, dup;
133 	char	*ptr, *rptr;
134 	char	tbuf[82], tdup[82];
135 	char	addr[22];
136 	char	boff[12];
137 	char	bhex[82], duphex[82];
138 	char	basc[40];
139 
140 	sw  = 0;
141 	rptr = ptr = buf;
142 	rm  = 16;
143 	duphex[0] = 0x00;
144 	dup = 0;
145 
146 	for (ct = 0; ct < len; ct++, ptr++, rptr++) {
147 		if (sw == 0) {
148 			scnprintf(addr, sizeof(addr), "%16.16llx", (__u64)rptr);
149 
150 			scnprintf(boff, sizeof(boff), "%4.4X", (__u32)ct);
151 			bhex[0] = '\0';
152 			basc[0] = '\0';
153 		}
154 		if ((sw == 4) || (sw == 12))
155 			strcat(bhex, " ");
156 		if (sw == 8)
157 			strcat(bhex, "	");
158 
159 		scnprintf(tbuf, sizeof(tbuf), "%2.2llX", (__u64)*ptr);
160 
161 		tbuf[2] = '\0';
162 		strcat(bhex, tbuf);
163 		if ((0 != isprint(*ptr)) && (*ptr >= 0x20))
164 			basc[sw] = *ptr;
165 		else
166 			basc[sw] = '.';
167 
168 		basc[sw+1] = '\0';
169 		sw++;
170 		rm--;
171 		if (sw != 16)
172 			continue;
173 		if ((strcmp(duphex, bhex)) != 0) {
174 			if (dup != 0) {
175 				scnprintf(tdup, sizeof(tdup),
176 					  "Duplicate as above to %s", addr);
177 				ctcm_pr_debug("		       --- %s ---\n",
178 						tdup);
179 			}
180 			ctcm_pr_debug("   %s (+%s) : %s  [%s]\n",
181 					addr, boff, bhex, basc);
182 			dup = 0;
183 			strscpy(duphex, bhex);
184 		} else
185 			dup++;
186 
187 		sw = 0;
188 		rm = 16;
189 	}  /* endfor */
190 
191 	if (sw != 0) {
192 		for ( ; rm > 0; rm--, sw++) {
193 			if ((sw == 4) || (sw == 12))
194 				strcat(bhex, " ");
195 			if (sw == 8)
196 				strcat(bhex, "	");
197 			strcat(bhex, "	");
198 			strcat(basc, " ");
199 		}
200 		if (dup != 0) {
201 			scnprintf(tdup, sizeof(tdup),
202 				  "Duplicate as above to %s", addr);
203 			ctcm_pr_debug("		       --- %s ---\n", tdup);
204 		}
205 		ctcm_pr_debug("   %s (+%s) : %s  [%s]\n",
206 					addr, boff, bhex, basc);
207 	} else {
208 		if (dup >= 1) {
209 			scnprintf(tdup, sizeof(tdup),
210 				  "Duplicate as above to %s", addr);
211 			ctcm_pr_debug("		       --- %s ---\n", tdup);
212 		}
213 		if (dup != 0) {
214 			ctcm_pr_debug("   %s (+%s) : %s  [%s]\n",
215 				addr, boff, bhex, basc);
216 		}
217 	}
218 
219 	return;
220 
221 }   /*	 end of ctcmpc_dumpit  */
222 #endif
223 
224 #ifdef DEBUGDATA
225 /*
226  * Dump header and first 16 bytes of an sk_buff for debugging purposes.
227  *
228  * skb		The sk_buff to dump.
229  * offset	Offset relative to skb-data, where to start the dump.
230  */
ctcmpc_dump_skb(struct sk_buff * skb,int offset)231 void ctcmpc_dump_skb(struct sk_buff *skb, int offset)
232 {
233 	__u8 *p = skb->data;
234 	struct th_header *header;
235 	struct pdu *pheader;
236 	int bl = skb->len;
237 	int i;
238 
239 	if (p == NULL)
240 		return;
241 
242 	p += offset;
243 	header = (struct th_header *)p;
244 
245 	ctcm_pr_debug("dump:\n");
246 	ctcm_pr_debug("skb len=%d \n", skb->len);
247 	if (skb->len > 2) {
248 		switch (header->th_ch_flag) {
249 		case TH_HAS_PDU:
250 			break;
251 		case 0x00:
252 		case TH_IS_XID:
253 			if ((header->th_blk_flag == TH_DATA_IS_XID) &&
254 			   (header->th_is_xid == 0x01))
255 				goto dumpth;
256 		case TH_SWEEP_REQ:
257 				goto dumpth;
258 		case TH_SWEEP_RESP:
259 				goto dumpth;
260 		default:
261 			break;
262 		}
263 
264 		pheader = (struct pdu *)p;
265 		ctcm_pr_debug("pdu->offset: %d hex: %04x\n",
266 			       pheader->pdu_offset, pheader->pdu_offset);
267 		ctcm_pr_debug("pdu->flag  : %02x\n", pheader->pdu_flag);
268 		ctcm_pr_debug("pdu->proto : %02x\n", pheader->pdu_proto);
269 		ctcm_pr_debug("pdu->seq   : %02x\n", pheader->pdu_seq);
270 					goto dumpdata;
271 
272 dumpth:
273 		ctcm_pr_debug("th->seg     : %02x\n", header->th_seg);
274 		ctcm_pr_debug("th->ch      : %02x\n", header->th_ch_flag);
275 		ctcm_pr_debug("th->blk_flag: %02x\n", header->th_blk_flag);
276 		ctcm_pr_debug("th->type    : %s\n",
277 			       (header->th_is_xid) ? "DATA" : "XID");
278 		ctcm_pr_debug("th->seqnum  : %04x\n", header->th_seq_num);
279 
280 	}
281 dumpdata:
282 	if (bl > 32)
283 		bl = 32;
284 	ctcm_pr_debug("data: ");
285 	for (i = 0; i < bl; i++)
286 		ctcm_pr_debug("%02x%s", *p++, (i % 16) ? " " : "\n");
287 	ctcm_pr_debug("\n");
288 }
289 #endif
290 
ctcmpc_get_dev(int port_num)291 static struct net_device *ctcmpc_get_dev(int port_num)
292 {
293 	char device[20];
294 	struct net_device *dev;
295 	struct ctcm_priv *priv;
296 
297 	scnprintf(device, sizeof(device), "%s%i", MPC_DEVICE_NAME, port_num);
298 
299 	dev = __dev_get_by_name(&init_net, device);
300 
301 	if (dev == NULL) {
302 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
303 			"%s: Device not found by name: %s",
304 					CTCM_FUNTAIL, device);
305 		return NULL;
306 	}
307 	priv = dev->ml_priv;
308 	if (priv == NULL) {
309 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
310 			"%s(%s): dev->ml_priv is NULL",
311 					CTCM_FUNTAIL, device);
312 		return NULL;
313 	}
314 	if (priv->mpcg == NULL) {
315 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
316 			"%s(%s): priv->mpcg is NULL",
317 					CTCM_FUNTAIL, device);
318 		return NULL;
319 	}
320 	return dev;
321 }
322 
323 /*
324  * ctc_mpc_alloc_channel
325  *	(exported interface)
326  *
327  * Device Initialization :
328  *	ACTPATH  driven IO operations
329  */
ctc_mpc_alloc_channel(int port_num,void (* callback)(int,int))330 int ctc_mpc_alloc_channel(int port_num, void (*callback)(int, int))
331 {
332 	struct net_device *dev;
333 	struct mpc_group *grp;
334 	struct ctcm_priv *priv;
335 
336 	dev = ctcmpc_get_dev(port_num);
337 	if (dev == NULL)
338 		return 1;
339 	priv = dev->ml_priv;
340 	grp = priv->mpcg;
341 
342 	grp->allochanfunc = callback;
343 	grp->port_num = port_num;
344 	grp->port_persist = 1;
345 
346 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
347 			"%s(%s): state=%s",
348 			CTCM_FUNTAIL, dev->name, fsm_getstate_str(grp->fsm));
349 
350 	switch (fsm_getstate(grp->fsm)) {
351 	case MPCG_STATE_INOP:
352 		/* Group is in the process of terminating */
353 		grp->alloc_called = 1;
354 		break;
355 	case MPCG_STATE_RESET:
356 		/* MPC Group will transition to state		  */
357 		/* MPCG_STATE_XID2INITW iff the minimum number	  */
358 		/* of 1 read and 1 write channel have successfully*/
359 		/* activated					  */
360 		/*fsm_newstate(grp->fsm, MPCG_STATE_XID2INITW);*/
361 		if (callback)
362 			grp->send_qllc_disc = 1;
363 		fallthrough;
364 	case MPCG_STATE_XID0IOWAIT:
365 		fsm_deltimer(&grp->timer);
366 		grp->outstanding_xid2 = 0;
367 		grp->outstanding_xid7 = 0;
368 		grp->outstanding_xid7_p2 = 0;
369 		grp->saved_xid2 = NULL;
370 		if (callback)
371 			ctcm_open(dev);
372 		fsm_event(priv->fsm, DEV_EVENT_START, dev);
373 		break;
374 	case MPCG_STATE_READY:
375 		/* XID exchanges completed after PORT was activated */
376 		/* Link station already active			    */
377 		/* Maybe timing issue...retry callback		    */
378 		grp->allocchan_callback_retries++;
379 		if (grp->allocchan_callback_retries < 4) {
380 			if (grp->allochanfunc)
381 				grp->allochanfunc(grp->port_num,
382 						  grp->group_max_buflen);
383 		} else {
384 			/* there are problems...bail out	    */
385 			/* there may be a state mismatch so restart */
386 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
387 			grp->allocchan_callback_retries = 0;
388 		}
389 		break;
390 	}
391 
392 	return 0;
393 }
394 EXPORT_SYMBOL(ctc_mpc_alloc_channel);
395 
396 /*
397  * ctc_mpc_establish_connectivity
398  *	(exported interface)
399  */
ctc_mpc_establish_connectivity(int port_num,void (* callback)(int,int,int))400 void ctc_mpc_establish_connectivity(int port_num,
401 				void (*callback)(int, int, int))
402 {
403 	struct net_device *dev;
404 	struct mpc_group *grp;
405 	struct ctcm_priv *priv;
406 	struct channel *rch, *wch;
407 
408 	dev = ctcmpc_get_dev(port_num);
409 	if (dev == NULL)
410 		return;
411 	priv = dev->ml_priv;
412 	grp = priv->mpcg;
413 	rch = priv->channel[CTCM_READ];
414 	wch = priv->channel[CTCM_WRITE];
415 
416 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
417 			"%s(%s): state=%s",
418 			CTCM_FUNTAIL, dev->name, fsm_getstate_str(grp->fsm));
419 
420 	grp->estconnfunc = callback;
421 	grp->port_num = port_num;
422 
423 	switch (fsm_getstate(grp->fsm)) {
424 	case MPCG_STATE_READY:
425 		/* XID exchanges completed after PORT was activated */
426 		/* Link station already active			    */
427 		/* Maybe timing issue...retry callback		    */
428 		fsm_deltimer(&grp->timer);
429 		grp->estconn_callback_retries++;
430 		if (grp->estconn_callback_retries < 4) {
431 			if (grp->estconnfunc) {
432 				grp->estconnfunc(grp->port_num, 0,
433 						grp->group_max_buflen);
434 				grp->estconnfunc = NULL;
435 			}
436 		} else {
437 			/* there are problems...bail out	 */
438 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
439 			grp->estconn_callback_retries = 0;
440 		}
441 		break;
442 	case MPCG_STATE_INOP:
443 	case MPCG_STATE_RESET:
444 		/* MPC Group is not ready to start XID - min num of */
445 		/* 1 read and 1 write channel have not been acquired*/
446 
447 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
448 			"%s(%s): REJECTED - inactive channels",
449 					CTCM_FUNTAIL, dev->name);
450 		if (grp->estconnfunc) {
451 			grp->estconnfunc(grp->port_num, -1, 0);
452 			grp->estconnfunc = NULL;
453 		}
454 		break;
455 	case MPCG_STATE_XID2INITW:
456 		/* alloc channel was called but no XID exchange    */
457 		/* has occurred. initiate xside XID exchange	   */
458 		/* make sure yside XID0 processing has not started */
459 
460 		if ((fsm_getstate(rch->fsm) > CH_XID0_PENDING) ||
461 			(fsm_getstate(wch->fsm) > CH_XID0_PENDING)) {
462 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
463 				"%s(%s): ABORT - PASSIVE XID",
464 					CTCM_FUNTAIL, dev->name);
465 			break;
466 		}
467 		grp->send_qllc_disc = 1;
468 		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIT);
469 		fsm_deltimer(&grp->timer);
470 		fsm_addtimer(&grp->timer, MPC_XID_TIMEOUT_VALUE,
471 						MPCG_EVENT_TIMER, dev);
472 		grp->outstanding_xid7 = 0;
473 		grp->outstanding_xid7_p2 = 0;
474 		grp->saved_xid2 = NULL;
475 		if ((rch->in_mpcgroup) &&
476 				(fsm_getstate(rch->fsm) == CH_XID0_PENDING))
477 			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, rch);
478 		else {
479 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
480 				"%s(%s): RX-%s not ready for ACTIVE XID0",
481 					CTCM_FUNTAIL, dev->name, rch->id);
482 			if (grp->estconnfunc) {
483 				grp->estconnfunc(grp->port_num, -1, 0);
484 				grp->estconnfunc = NULL;
485 			}
486 			fsm_deltimer(&grp->timer);
487 			goto done;
488 		}
489 		if ((wch->in_mpcgroup) &&
490 				(fsm_getstate(wch->fsm) == CH_XID0_PENDING))
491 			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, wch);
492 		else {
493 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
494 				"%s(%s): WX-%s not ready for ACTIVE XID0",
495 					CTCM_FUNTAIL, dev->name, wch->id);
496 			if (grp->estconnfunc) {
497 				grp->estconnfunc(grp->port_num, -1, 0);
498 				grp->estconnfunc = NULL;
499 			}
500 			fsm_deltimer(&grp->timer);
501 			goto done;
502 			}
503 		break;
504 	case MPCG_STATE_XID0IOWAIT:
505 		/* already in active XID negotiations */
506 	default:
507 		break;
508 	}
509 
510 done:
511 	CTCM_PR_DEBUG("Exit %s()\n", __func__);
512 	return;
513 }
514 EXPORT_SYMBOL(ctc_mpc_establish_connectivity);
515 
516 /*
517  * ctc_mpc_dealloc_ch
518  *	(exported interface)
519  */
ctc_mpc_dealloc_ch(int port_num)520 void ctc_mpc_dealloc_ch(int port_num)
521 {
522 	struct net_device *dev;
523 	struct ctcm_priv *priv;
524 	struct mpc_group *grp;
525 
526 	dev = ctcmpc_get_dev(port_num);
527 	if (dev == NULL)
528 		return;
529 	priv = dev->ml_priv;
530 	grp = priv->mpcg;
531 
532 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_DEBUG,
533 			"%s: %s: refcount = %d\n",
534 			CTCM_FUNTAIL, dev->name, netdev_refcnt_read(dev));
535 
536 	fsm_deltimer(&priv->restart_timer);
537 	grp->channels_terminating = 0;
538 	fsm_deltimer(&grp->timer);
539 	grp->allochanfunc = NULL;
540 	grp->estconnfunc = NULL;
541 	grp->port_persist = 0;
542 	grp->send_qllc_disc = 0;
543 	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
544 
545 	ctcm_close(dev);
546 	return;
547 }
548 EXPORT_SYMBOL(ctc_mpc_dealloc_ch);
549 
550 /*
551  * ctc_mpc_flow_control
552  *	(exported interface)
553  */
ctc_mpc_flow_control(int port_num,int flowc)554 void ctc_mpc_flow_control(int port_num, int flowc)
555 {
556 	struct ctcm_priv *priv;
557 	struct mpc_group *grp;
558 	struct net_device *dev;
559 	struct channel *rch;
560 	int mpcg_state;
561 
562 	dev = ctcmpc_get_dev(port_num);
563 	if (dev == NULL)
564 		return;
565 	priv = dev->ml_priv;
566 	grp = priv->mpcg;
567 
568 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
569 			"%s: %s: flowc = %d",
570 				CTCM_FUNTAIL, dev->name, flowc);
571 
572 	rch = priv->channel[CTCM_READ];
573 
574 	mpcg_state = fsm_getstate(grp->fsm);
575 	switch (flowc) {
576 	case 1:
577 		if (mpcg_state == MPCG_STATE_FLOWC)
578 			break;
579 		if (mpcg_state == MPCG_STATE_READY) {
580 			if (grp->flow_off_called == 1)
581 				grp->flow_off_called = 0;
582 			else
583 				fsm_newstate(grp->fsm, MPCG_STATE_FLOWC);
584 			break;
585 		}
586 		break;
587 	case 0:
588 		if (mpcg_state == MPCG_STATE_FLOWC) {
589 			fsm_newstate(grp->fsm, MPCG_STATE_READY);
590 			/* ensure any data that has accumulated */
591 			/* on the io_queue will now be sen t	*/
592 			tasklet_schedule(&rch->ch_tasklet);
593 		}
594 		/* possible race condition			*/
595 		if (mpcg_state == MPCG_STATE_READY) {
596 			grp->flow_off_called = 1;
597 			break;
598 		}
599 		break;
600 	}
601 
602 }
603 EXPORT_SYMBOL(ctc_mpc_flow_control);
604 
605 static int mpc_send_qllc_discontact(struct net_device *);
606 
607 /*
608  * helper function of ctcmpc_unpack_skb
609 */
mpc_rcvd_sweep_resp(struct mpcg_info * mpcginfo)610 static void mpc_rcvd_sweep_resp(struct mpcg_info *mpcginfo)
611 {
612 	struct channel	  *rch = mpcginfo->ch;
613 	struct net_device *dev = rch->netdev;
614 	struct ctcm_priv   *priv = dev->ml_priv;
615 	struct mpc_group  *grp = priv->mpcg;
616 	struct channel	  *ch = priv->channel[CTCM_WRITE];
617 
618 	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, ch, ch->id);
619 	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
620 
621 	grp->sweep_rsp_pend_num--;
622 
623 	if ((grp->sweep_req_pend_num == 0) &&
624 			(grp->sweep_rsp_pend_num == 0)) {
625 		fsm_deltimer(&ch->sweep_timer);
626 		grp->in_sweep = 0;
627 		rch->th_seq_num = 0x00;
628 		ch->th_seq_num = 0x00;
629 		ctcm_clear_busy_do(dev);
630 	}
631 
632 	return;
633 
634 }
635 
636 /*
637  * helper function of mpc_rcvd_sweep_req
638  * which is a helper of ctcmpc_unpack_skb
639  */
ctcmpc_send_sweep_resp(struct channel * rch)640 static void ctcmpc_send_sweep_resp(struct channel *rch)
641 {
642 	struct net_device *dev = rch->netdev;
643 	struct ctcm_priv *priv = dev->ml_priv;
644 	struct mpc_group *grp = priv->mpcg;
645 	struct th_sweep *header;
646 	struct sk_buff *sweep_skb;
647 	struct channel *ch  = priv->channel[CTCM_WRITE];
648 
649 	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, rch, rch->id);
650 
651 	sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
652 	if (sweep_skb == NULL) {
653 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
654 			"%s(%s): sweep_skb allocation ERROR\n",
655 			CTCM_FUNTAIL, rch->id);
656 		goto done;
657 	}
658 
659 	header = skb_put_zero(sweep_skb, TH_SWEEP_LENGTH);
660 	header->th.th_ch_flag	= TH_SWEEP_RESP;
661 	header->sw.th_last_seq	= ch->th_seq_num;
662 
663 	netif_trans_update(dev);
664 	skb_queue_tail(&ch->sweep_queue, sweep_skb);
665 
666 	fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
667 
668 	return;
669 
670 done:
671 	grp->in_sweep = 0;
672 	ctcm_clear_busy_do(dev);
673 	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
674 
675 	return;
676 }
677 
678 /*
679  * helper function of ctcmpc_unpack_skb
680  */
mpc_rcvd_sweep_req(struct mpcg_info * mpcginfo)681 static void mpc_rcvd_sweep_req(struct mpcg_info *mpcginfo)
682 {
683 	struct channel	  *rch     = mpcginfo->ch;
684 	struct net_device *dev     = rch->netdev;
685 	struct ctcm_priv  *priv = dev->ml_priv;
686 	struct mpc_group  *grp  = priv->mpcg;
687 	struct channel	  *ch	   = priv->channel[CTCM_WRITE];
688 
689 	if (do_debug)
690 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
691 			" %s(): ch=0x%p id=%s\n", __func__, ch, ch->id);
692 
693 	if (grp->in_sweep == 0) {
694 		grp->in_sweep = 1;
695 		ctcm_test_and_set_busy(dev);
696 		grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
697 		grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
698 	}
699 
700 	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
701 
702 	grp->sweep_req_pend_num--;
703 	ctcmpc_send_sweep_resp(ch);
704 	kfree(mpcginfo);
705 	return;
706 }
707 
708 /*
709   * MPC Group Station FSM definitions
710  */
711 static const char *mpcg_event_names[] = {
712 	[MPCG_EVENT_INOP]	= "INOP Condition",
713 	[MPCG_EVENT_DISCONC]	= "Discontact Received",
714 	[MPCG_EVENT_XID0DO]	= "Channel Active - Start XID",
715 	[MPCG_EVENT_XID2]	= "XID2 Received",
716 	[MPCG_EVENT_XID2DONE]	= "XID0 Complete",
717 	[MPCG_EVENT_XID7DONE]	= "XID7 Complete",
718 	[MPCG_EVENT_TIMER]	= "XID Setup Timer",
719 	[MPCG_EVENT_DOIO]	= "XID DoIO",
720 };
721 
722 static const char *mpcg_state_names[] = {
723 	[MPCG_STATE_RESET]	= "Reset",
724 	[MPCG_STATE_INOP]	= "INOP",
725 	[MPCG_STATE_XID2INITW]	= "Passive XID- XID0 Pending Start",
726 	[MPCG_STATE_XID2INITX]	= "Passive XID- XID0 Pending Complete",
727 	[MPCG_STATE_XID7INITW]	= "Passive XID- XID7 Pending P1 Start",
728 	[MPCG_STATE_XID7INITX]	= "Passive XID- XID7 Pending P2 Complete",
729 	[MPCG_STATE_XID0IOWAIT]	= "Active  XID- XID0 Pending Start",
730 	[MPCG_STATE_XID0IOWAIX]	= "Active  XID- XID0 Pending Complete",
731 	[MPCG_STATE_XID7INITI]	= "Active  XID- XID7 Pending Start",
732 	[MPCG_STATE_XID7INITZ]	= "Active  XID- XID7 Pending Complete ",
733 	[MPCG_STATE_XID7INITF]	= "XID        - XID7 Complete ",
734 	[MPCG_STATE_FLOWC]	= "FLOW CONTROL ON",
735 	[MPCG_STATE_READY]	= "READY",
736 };
737 
738 /*
739  * The MPC Group Station FSM
740  *   22 events
741  */
742 static const fsm_node mpcg_fsm[] = {
743 	{ MPCG_STATE_RESET,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
744 	{ MPCG_STATE_INOP,	MPCG_EVENT_INOP,	mpc_action_nop        },
745 	{ MPCG_STATE_FLOWC,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
746 
747 	{ MPCG_STATE_READY,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
748 	{ MPCG_STATE_READY,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
749 
750 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
751 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
752 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
753 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
754 	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
755 
756 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
757 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
758 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
759 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
760 	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
761 
762 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
763 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
764 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
765 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
766 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
767 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
768 	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
769 
770 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
771 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
772 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
773 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
774 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
775 	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
776 
777 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
778 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DISCONC,	mpc_action_discontact },
779 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
780 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_INOP,	mpc_action_go_inop    },
781 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_TIMER,	mpc_action_timeout    },
782 	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
783 
784 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
785 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DISCONC,	mpc_action_discontact },
786 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
787 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_INOP,	mpc_action_go_inop    },
788 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_TIMER,	mpc_action_timeout    },
789 	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
790 
791 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
792 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
793 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
794 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
795 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
796 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
797 	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
798 
799 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
800 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
801 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
802 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
803 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
804 	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
805 
806 	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
807 	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_XID7DONE,	mpc_action_go_ready   },
808 };
809 
810 static int mpcg_fsm_len = ARRAY_SIZE(mpcg_fsm);
811 
812 /*
813  * MPC Group Station FSM action
814  * CTCM_PROTO_MPC only
815  */
mpc_action_go_ready(fsm_instance * fsm,int event,void * arg)816 static void mpc_action_go_ready(fsm_instance *fsm, int event, void *arg)
817 {
818 	struct net_device *dev = arg;
819 	struct ctcm_priv *priv = dev->ml_priv;
820 	struct mpc_group *grp = priv->mpcg;
821 
822 	if (grp == NULL) {
823 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
824 			"%s(%s): No MPC group",
825 				CTCM_FUNTAIL, dev->name);
826 		return;
827 	}
828 
829 	fsm_deltimer(&grp->timer);
830 
831 	if (grp->saved_xid2->xid2_flag2 == 0x40) {
832 		priv->xid->xid2_flag2 = 0x00;
833 		if (grp->estconnfunc) {
834 			grp->estconnfunc(grp->port_num, 1,
835 					grp->group_max_buflen);
836 			grp->estconnfunc = NULL;
837 		} else if (grp->allochanfunc)
838 			grp->send_qllc_disc = 1;
839 
840 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
841 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
842 				"%s(%s): fails",
843 					CTCM_FUNTAIL, dev->name);
844 		return;
845 	}
846 
847 	grp->port_persist = 1;
848 	grp->out_of_sequence = 0;
849 	grp->estconn_called = 0;
850 
851 	tasklet_hi_schedule(&grp->mpc_tasklet2);
852 
853 	return;
854 }
855 
856 /*
857  * helper of ctcm_init_netdevice
858  * CTCM_PROTO_MPC only
859  */
mpc_group_ready(unsigned long adev)860 void mpc_group_ready(unsigned long adev)
861 {
862 	struct net_device *dev = (struct net_device *)adev;
863 	struct ctcm_priv *priv = dev->ml_priv;
864 	struct mpc_group *grp = priv->mpcg;
865 	struct channel *ch = NULL;
866 
867 	if (grp == NULL) {
868 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
869 			"%s(%s): No MPC group",
870 				CTCM_FUNTAIL, dev->name);
871 		return;
872 	}
873 
874 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
875 		"%s: %s: GROUP TRANSITIONED TO READY, maxbuf = %d\n",
876 			CTCM_FUNTAIL, dev->name, grp->group_max_buflen);
877 
878 	fsm_newstate(grp->fsm, MPCG_STATE_READY);
879 
880 	/* Put up a read on the channel */
881 	ch = priv->channel[CTCM_READ];
882 	ch->pdu_seq = 0;
883 	CTCM_PR_DBGDATA("ctcmpc: %s() ToDCM_pdu_seq= %08x\n" ,
884 			__func__, ch->pdu_seq);
885 
886 	ctcmpc_chx_rxidle(ch->fsm, CTC_EVENT_START, ch);
887 	/* Put the write channel in idle state */
888 	ch = priv->channel[CTCM_WRITE];
889 	if (ch->collect_len > 0) {
890 		spin_lock(&ch->collect_lock);
891 		ctcm_purge_skb_queue(&ch->collect_queue);
892 		ch->collect_len = 0;
893 		spin_unlock(&ch->collect_lock);
894 	}
895 	ctcm_chx_txidle(ch->fsm, CTC_EVENT_START, ch);
896 	ctcm_clear_busy(dev);
897 
898 	if (grp->estconnfunc) {
899 		grp->estconnfunc(grp->port_num, 0,
900 				    grp->group_max_buflen);
901 		grp->estconnfunc = NULL;
902 	} else if (grp->allochanfunc) {
903 		grp->allochanfunc(grp->port_num, grp->group_max_buflen);
904 	}
905 
906 	grp->send_qllc_disc = 1;
907 	grp->changed_side = 0;
908 
909 	return;
910 
911 }
912 
913 /*
914  * Increment the MPC Group Active Channel Counts
915  * helper of dev_action (called from channel fsm)
916  */
mpc_channel_action(struct channel * ch,int direction,int action)917 void mpc_channel_action(struct channel *ch, int direction, int action)
918 {
919 	struct net_device  *dev  = ch->netdev;
920 	struct ctcm_priv   *priv = dev->ml_priv;
921 	struct mpc_group   *grp  = priv->mpcg;
922 
923 	if (grp == NULL) {
924 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
925 			"%s(%s): No MPC group",
926 				CTCM_FUNTAIL, dev->name);
927 		return;
928 	}
929 
930 	CTCM_PR_DEBUG("enter %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
931 
932 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
933 		"%s: %i / Grp:%s total_channels=%i, active_channels: "
934 		"read=%i, write=%i\n", __func__, action,
935 		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
936 		grp->active_channels[CTCM_READ],
937 		grp->active_channels[CTCM_WRITE]);
938 
939 	if ((action == MPC_CHANNEL_ADD) && (ch->in_mpcgroup == 0)) {
940 		grp->num_channel_paths++;
941 		grp->active_channels[direction]++;
942 		grp->outstanding_xid2++;
943 		ch->in_mpcgroup = 1;
944 
945 		if (ch->xid_skb != NULL)
946 			dev_kfree_skb_any(ch->xid_skb);
947 
948 		ch->xid_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT,
949 					GFP_ATOMIC | GFP_DMA);
950 		if (ch->xid_skb == NULL) {
951 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
952 				"%s(%s): Couldn't alloc ch xid_skb\n",
953 				CTCM_FUNTAIL, dev->name);
954 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
955 			return;
956 		}
957 		ch->xid_skb_data = ch->xid_skb->data;
958 		ch->xid_th = (struct th_header *)ch->xid_skb->data;
959 		skb_put(ch->xid_skb, TH_HEADER_LENGTH);
960 		ch->xid = (struct xid2 *)skb_tail_pointer(ch->xid_skb);
961 		skb_put(ch->xid_skb, XID2_LENGTH);
962 		ch->xid_id = skb_tail_pointer(ch->xid_skb);
963 		ch->xid_skb->data = ch->xid_skb_data;
964 		skb_reset_tail_pointer(ch->xid_skb);
965 		ch->xid_skb->len = 0;
966 
967 		skb_put_data(ch->xid_skb, grp->xid_skb->data,
968 			     grp->xid_skb->len);
969 
970 		ch->xid->xid2_dlc_type =
971 			((CHANNEL_DIRECTION(ch->flags) == CTCM_READ)
972 				? XID2_READ_SIDE : XID2_WRITE_SIDE);
973 
974 		if (CHANNEL_DIRECTION(ch->flags) == CTCM_WRITE)
975 			ch->xid->xid2_buf_len = 0x00;
976 
977 		ch->xid_skb->data = ch->xid_skb_data;
978 		skb_reset_tail_pointer(ch->xid_skb);
979 		ch->xid_skb->len = 0;
980 
981 		fsm_newstate(ch->fsm, CH_XID0_PENDING);
982 
983 		if ((grp->active_channels[CTCM_READ] > 0) &&
984 		    (grp->active_channels[CTCM_WRITE] > 0) &&
985 			(fsm_getstate(grp->fsm) < MPCG_STATE_XID2INITW)) {
986 			fsm_newstate(grp->fsm, MPCG_STATE_XID2INITW);
987 			CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
988 				"%s: %s: MPC GROUP CHANNELS ACTIVE\n",
989 						__func__, dev->name);
990 		}
991 	} else if ((action == MPC_CHANNEL_REMOVE) &&
992 			(ch->in_mpcgroup == 1)) {
993 		ch->in_mpcgroup = 0;
994 		grp->num_channel_paths--;
995 		grp->active_channels[direction]--;
996 
997 		if (ch->xid_skb != NULL)
998 			dev_kfree_skb_any(ch->xid_skb);
999 		ch->xid_skb = NULL;
1000 
1001 		if (grp->channels_terminating)
1002 					goto done;
1003 
1004 		if (((grp->active_channels[CTCM_READ] == 0) &&
1005 					(grp->active_channels[CTCM_WRITE] > 0))
1006 			|| ((grp->active_channels[CTCM_WRITE] == 0) &&
1007 					(grp->active_channels[CTCM_READ] > 0)))
1008 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1009 	}
1010 done:
1011 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
1012 		"exit %s: %i / Grp:%s total_channels=%i, active_channels: "
1013 		"read=%i, write=%i\n", __func__, action,
1014 		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
1015 		grp->active_channels[CTCM_READ],
1016 		grp->active_channels[CTCM_WRITE]);
1017 
1018 	CTCM_PR_DEBUG("exit %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
1019 }
1020 
1021 /*
1022  * Unpack a just received skb and hand it over to
1023  * upper layers.
1024  * special MPC version of unpack_skb.
1025  *
1026  * ch		The channel where this skb has been received.
1027  * pskb		The received skb.
1028  */
ctcmpc_unpack_skb(struct channel * ch,struct sk_buff * pskb)1029 static void ctcmpc_unpack_skb(struct channel *ch, struct sk_buff *pskb)
1030 {
1031 	struct net_device *dev	= ch->netdev;
1032 	struct ctcm_priv *priv = dev->ml_priv;
1033 	struct mpc_group *grp = priv->mpcg;
1034 	struct pdu *curr_pdu;
1035 	struct mpcg_info *mpcginfo;
1036 	struct th_header *header = NULL;
1037 	struct th_sweep *sweep = NULL;
1038 	int pdu_last_seen = 0;
1039 	__u32 new_len;
1040 	struct sk_buff *skb;
1041 	int skblen;
1042 	int sendrc = 0;
1043 
1044 	CTCM_PR_DEBUG("ctcmpc enter: %s() %s cp:%i ch:%s\n",
1045 			__func__, dev->name, smp_processor_id(), ch->id);
1046 
1047 	header = (struct th_header *)pskb->data;
1048 	if ((header->th_seg == 0) &&
1049 		(header->th_ch_flag == 0) &&
1050 		(header->th_blk_flag == 0) &&
1051 		(header->th_seq_num == 0))
1052 		/* nothing for us */	goto done;
1053 
1054 	CTCM_PR_DBGDATA("%s: th_header\n", __func__);
1055 	CTCM_D3_DUMP((char *)header, TH_HEADER_LENGTH);
1056 	CTCM_PR_DBGDATA("%s: pskb len: %04x \n", __func__, pskb->len);
1057 
1058 	pskb->dev = dev;
1059 	pskb->ip_summed = CHECKSUM_UNNECESSARY;
1060 	skb_pull(pskb, TH_HEADER_LENGTH);
1061 
1062 	if (likely(header->th_ch_flag == TH_HAS_PDU)) {
1063 		CTCM_PR_DBGDATA("%s: came into th_has_pdu\n", __func__);
1064 		if ((fsm_getstate(grp->fsm) == MPCG_STATE_FLOWC) ||
1065 		   ((fsm_getstate(grp->fsm) == MPCG_STATE_READY) &&
1066 		    (header->th_seq_num != ch->th_seq_num + 1) &&
1067 		    (ch->th_seq_num != 0))) {
1068 			/* This is NOT the next segment		*
1069 			 * we are not the correct race winner	*
1070 			 * go away and let someone else win	*
1071 			 * BUT..this only applies if xid negot	*
1072 			 * is done				*
1073 			*/
1074 			grp->out_of_sequence += 1;
1075 			__skb_push(pskb, TH_HEADER_LENGTH);
1076 			skb_queue_tail(&ch->io_queue, pskb);
1077 			CTCM_PR_DBGDATA("%s: th_seq_num expect:%08x "
1078 					"got:%08x\n", __func__,
1079 				ch->th_seq_num + 1, header->th_seq_num);
1080 
1081 			return;
1082 		}
1083 		grp->out_of_sequence = 0;
1084 		ch->th_seq_num = header->th_seq_num;
1085 
1086 		CTCM_PR_DBGDATA("ctcmpc: %s() FromVTAM_th_seq=%08x\n",
1087 					__func__, ch->th_seq_num);
1088 
1089 		if (unlikely(fsm_getstate(grp->fsm) != MPCG_STATE_READY))
1090 					goto done;
1091 		while ((pskb->len > 0) && !pdu_last_seen) {
1092 			curr_pdu = (struct pdu *)pskb->data;
1093 
1094 			CTCM_PR_DBGDATA("%s: pdu_header\n", __func__);
1095 			CTCM_D3_DUMP((char *)pskb->data, PDU_HEADER_LENGTH);
1096 			CTCM_PR_DBGDATA("%s: pskb len: %04x \n",
1097 						__func__, pskb->len);
1098 
1099 			skb_pull(pskb, PDU_HEADER_LENGTH);
1100 
1101 			if (curr_pdu->pdu_flag & PDU_LAST)
1102 				pdu_last_seen = 1;
1103 			if (curr_pdu->pdu_flag & PDU_CNTL)
1104 				pskb->protocol = htons(ETH_P_SNAP);
1105 			else
1106 				pskb->protocol = htons(ETH_P_SNA_DIX);
1107 
1108 			if ((pskb->len <= 0) || (pskb->len > ch->max_bufsize)) {
1109 				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1110 					"%s(%s): Dropping packet with "
1111 					"illegal siize %d",
1112 					CTCM_FUNTAIL, dev->name, pskb->len);
1113 
1114 				priv->stats.rx_dropped++;
1115 				priv->stats.rx_length_errors++;
1116 				goto done;
1117 			}
1118 			skb_reset_mac_header(pskb);
1119 			new_len = curr_pdu->pdu_offset;
1120 			CTCM_PR_DBGDATA("%s: new_len: %04x \n",
1121 						__func__, new_len);
1122 			if ((new_len == 0) || (new_len > pskb->len)) {
1123 				/* should never happen		    */
1124 				/* pskb len must be hosed...bail out */
1125 				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1126 					"%s(%s): non valid pdu_offset: %04x",
1127 					/* "data may be lost", */
1128 					CTCM_FUNTAIL, dev->name, new_len);
1129 				goto done;
1130 			}
1131 			skb = __dev_alloc_skb(new_len+4, GFP_ATOMIC);
1132 
1133 			if (!skb) {
1134 				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1135 					"%s(%s): MEMORY allocation error",
1136 						CTCM_FUNTAIL, dev->name);
1137 				priv->stats.rx_dropped++;
1138 				fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1139 				goto done;
1140 			}
1141 			skb_put_data(skb, pskb->data, new_len);
1142 
1143 			skb_reset_mac_header(skb);
1144 			skb->dev = pskb->dev;
1145 			skb->protocol = pskb->protocol;
1146 			skb->ip_summed = CHECKSUM_UNNECESSARY;
1147 			*((__u32 *) skb_push(skb, 4)) = ch->pdu_seq;
1148 			ch->pdu_seq++;
1149 
1150 			if (do_debug_data) {
1151 				ctcm_pr_debug("%s: ToDCM_pdu_seq= %08x\n",
1152 						__func__, ch->pdu_seq);
1153 				ctcm_pr_debug("%s: skb:%0lx "
1154 					"skb len: %d \n", __func__,
1155 					(unsigned long)skb, skb->len);
1156 				ctcm_pr_debug("%s: up to 32 bytes "
1157 					"of pdu_data sent\n", __func__);
1158 				ctcmpc_dump32((char *)skb->data, skb->len);
1159 			}
1160 
1161 			skblen = skb->len;
1162 			sendrc = netif_rx(skb);
1163 			priv->stats.rx_packets++;
1164 			priv->stats.rx_bytes += skblen;
1165 			skb_pull(pskb, new_len); /* point to next PDU */
1166 		}
1167 	} else {
1168 		mpcginfo = kmalloc(sizeof(struct mpcg_info), GFP_ATOMIC);
1169 		if (mpcginfo == NULL)
1170 					goto done;
1171 
1172 		mpcginfo->ch = ch;
1173 		mpcginfo->th = header;
1174 		mpcginfo->skb = pskb;
1175 		CTCM_PR_DEBUG("%s: Not PDU - may be control pkt\n",
1176 					__func__);
1177 		/*  it's a sweep?   */
1178 		sweep = (struct th_sweep *)pskb->data;
1179 		mpcginfo->sweep = sweep;
1180 		if (header->th_ch_flag == TH_SWEEP_REQ)
1181 			mpc_rcvd_sweep_req(mpcginfo);
1182 		else if (header->th_ch_flag == TH_SWEEP_RESP)
1183 			mpc_rcvd_sweep_resp(mpcginfo);
1184 		else if (header->th_blk_flag == TH_DATA_IS_XID) {
1185 			struct xid2 *thisxid = (struct xid2 *)pskb->data;
1186 			skb_pull(pskb, XID2_LENGTH);
1187 			mpcginfo->xid = thisxid;
1188 			fsm_event(grp->fsm, MPCG_EVENT_XID2, mpcginfo);
1189 		} else if (header->th_blk_flag == TH_DISCONTACT)
1190 			fsm_event(grp->fsm, MPCG_EVENT_DISCONC, mpcginfo);
1191 		else if (header->th_seq_num != 0) {
1192 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1193 				"%s(%s): control pkt expected\n",
1194 						CTCM_FUNTAIL, dev->name);
1195 			priv->stats.rx_dropped++;
1196 			/* mpcginfo only used for non-data transfers */
1197 			if (do_debug_data)
1198 				ctcmpc_dump_skb(pskb, -8);
1199 		}
1200 		kfree(mpcginfo);
1201 	}
1202 done:
1203 
1204 	dev_kfree_skb_any(pskb);
1205 	if (sendrc == NET_RX_DROP) {
1206 		dev_warn(&dev->dev,
1207 			"The network backlog for %s is exceeded, "
1208 			"package dropped\n", __func__);
1209 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1210 	}
1211 
1212 	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
1213 			__func__, dev->name, ch, ch->id);
1214 }
1215 
1216 /*
1217  * tasklet helper for mpc's skb unpacking.
1218  *
1219  * ch		The channel to work on.
1220  * Allow flow control back pressure to occur here.
1221  * Throttling back channel can result in excessive
1222  * channel inactivity and system deact of channel
1223  */
ctcmpc_bh(unsigned long thischan)1224 void ctcmpc_bh(unsigned long thischan)
1225 {
1226 	struct channel	  *ch	= (struct channel *)thischan;
1227 	struct sk_buff	  *skb;
1228 	struct net_device *dev	= ch->netdev;
1229 	struct ctcm_priv  *priv	= dev->ml_priv;
1230 	struct mpc_group  *grp	= priv->mpcg;
1231 
1232 	CTCM_PR_DEBUG("%s cp:%i enter:  %s() %s\n",
1233 	       dev->name, smp_processor_id(), __func__, ch->id);
1234 	/* caller has requested driver to throttle back */
1235 	while ((fsm_getstate(grp->fsm) != MPCG_STATE_FLOWC) &&
1236 			(skb = skb_dequeue(&ch->io_queue))) {
1237 		ctcmpc_unpack_skb(ch, skb);
1238 		if (grp->out_of_sequence > 20) {
1239 			/* assume data loss has occurred if */
1240 			/* missing seq_num for extended     */
1241 			/* period of time		    */
1242 			grp->out_of_sequence = 0;
1243 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1244 			break;
1245 		}
1246 		if (skb == skb_peek(&ch->io_queue))
1247 			break;
1248 	}
1249 	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
1250 			__func__, dev->name, ch, ch->id);
1251 	return;
1252 }
1253 
1254 /*
1255  *  MPC Group Initializations
1256  */
ctcmpc_init_mpc_group(struct ctcm_priv * priv)1257 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv)
1258 {
1259 	struct mpc_group *grp;
1260 
1261 	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
1262 			"Enter %s(%p)", CTCM_FUNTAIL, priv);
1263 
1264 	grp = kzalloc(sizeof(struct mpc_group), GFP_KERNEL);
1265 	if (grp == NULL)
1266 		return NULL;
1267 
1268 	grp->fsm = init_fsm("mpcg", mpcg_state_names, mpcg_event_names,
1269 			MPCG_NR_STATES, MPCG_NR_EVENTS, mpcg_fsm,
1270 			mpcg_fsm_len, GFP_KERNEL);
1271 	if (grp->fsm == NULL) {
1272 		kfree(grp);
1273 		return NULL;
1274 	}
1275 
1276 	fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1277 	fsm_settimer(grp->fsm, &grp->timer);
1278 
1279 	grp->xid_skb =
1280 		 __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
1281 	if (grp->xid_skb == NULL) {
1282 		kfree_fsm(grp->fsm);
1283 		kfree(grp);
1284 		return NULL;
1285 	}
1286 	/*  base xid for all channels in group  */
1287 	grp->xid_skb_data = grp->xid_skb->data;
1288 	grp->xid_th = (struct th_header *)grp->xid_skb->data;
1289 	skb_put_data(grp->xid_skb, &thnorm, TH_HEADER_LENGTH);
1290 
1291 	grp->xid = (struct xid2 *)skb_tail_pointer(grp->xid_skb);
1292 	skb_put_data(grp->xid_skb, &init_xid, XID2_LENGTH);
1293 	grp->xid->xid2_adj_id = jiffies | 0xfff00000;
1294 	grp->xid->xid2_sender_id = jiffies;
1295 
1296 	grp->xid_id = skb_tail_pointer(grp->xid_skb);
1297 	skb_put_data(grp->xid_skb, "VTAM", 4);
1298 
1299 	grp->rcvd_xid_skb =
1300 		__dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
1301 	if (grp->rcvd_xid_skb == NULL) {
1302 		kfree_fsm(grp->fsm);
1303 		dev_kfree_skb(grp->xid_skb);
1304 		kfree(grp);
1305 		return NULL;
1306 	}
1307 	grp->rcvd_xid_data = grp->rcvd_xid_skb->data;
1308 	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
1309 	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
1310 	grp->saved_xid2 = NULL;
1311 	priv->xid = grp->xid;
1312 	priv->mpcg = grp;
1313 	return grp;
1314 }
1315 
1316 /*
1317  * The MPC Group Station FSM
1318  */
1319 
1320 /*
1321  * MPC Group Station FSM actions
1322  * CTCM_PROTO_MPC only
1323  */
1324 
1325 /*
1326  * NOP action for statemachines
1327  */
mpc_action_nop(fsm_instance * fi,int event,void * arg)1328 static void mpc_action_nop(fsm_instance *fi, int event, void *arg)
1329 {
1330 }
1331 
1332 /*
1333  * invoked when the device transitions to dev_stopped
1334  * MPC will stop each individual channel if a single XID failure
1335  * occurs, or will intitiate all channels be stopped if a GROUP
1336  * level failure occurs.
1337  */
mpc_action_go_inop(fsm_instance * fi,int event,void * arg)1338 static void mpc_action_go_inop(fsm_instance *fi, int event, void *arg)
1339 {
1340 	struct net_device  *dev = arg;
1341 	struct ctcm_priv    *priv;
1342 	struct mpc_group *grp;
1343 	struct channel *wch;
1344 
1345 	CTCM_PR_DEBUG("Enter %s: %s\n",	__func__, dev->name);
1346 
1347 	priv  = dev->ml_priv;
1348 	grp =  priv->mpcg;
1349 	grp->flow_off_called = 0;
1350 	fsm_deltimer(&grp->timer);
1351 	if (grp->channels_terminating)
1352 			return;
1353 
1354 	grp->channels_terminating = 1;
1355 	grp->saved_state = fsm_getstate(grp->fsm);
1356 	fsm_newstate(grp->fsm, MPCG_STATE_INOP);
1357 	if (grp->saved_state > MPCG_STATE_XID7INITF)
1358 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1359 			"%s(%s): MPC GROUP INOPERATIVE",
1360 				CTCM_FUNTAIL, dev->name);
1361 	if ((grp->saved_state != MPCG_STATE_RESET) ||
1362 		/* dealloc_channel has been called */
1363 		(grp->port_persist == 0))
1364 		fsm_deltimer(&priv->restart_timer);
1365 
1366 	wch = priv->channel[CTCM_WRITE];
1367 
1368 	switch (grp->saved_state) {
1369 	case MPCG_STATE_RESET:
1370 	case MPCG_STATE_INOP:
1371 	case MPCG_STATE_XID2INITW:
1372 	case MPCG_STATE_XID0IOWAIT:
1373 	case MPCG_STATE_XID2INITX:
1374 	case MPCG_STATE_XID7INITW:
1375 	case MPCG_STATE_XID7INITX:
1376 	case MPCG_STATE_XID0IOWAIX:
1377 	case MPCG_STATE_XID7INITI:
1378 	case MPCG_STATE_XID7INITZ:
1379 	case MPCG_STATE_XID7INITF:
1380 		break;
1381 	case MPCG_STATE_FLOWC:
1382 	case MPCG_STATE_READY:
1383 	default:
1384 		tasklet_hi_schedule(&wch->ch_disc_tasklet);
1385 	}
1386 
1387 	grp->xid2_tgnum = 0;
1388 	grp->group_max_buflen = 0;  /*min of all received */
1389 	grp->outstanding_xid2 = 0;
1390 	grp->outstanding_xid7 = 0;
1391 	grp->outstanding_xid7_p2 = 0;
1392 	grp->saved_xid2 = NULL;
1393 	grp->xidnogood = 0;
1394 	grp->changed_side = 0;
1395 
1396 	grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
1397 	skb_reset_tail_pointer(grp->rcvd_xid_skb);
1398 	grp->rcvd_xid_skb->len = 0;
1399 	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
1400 	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
1401 
1402 	if (grp->send_qllc_disc == 1) {
1403 		grp->send_qllc_disc = 0;
1404 		mpc_send_qllc_discontact(dev);
1405 	}
1406 
1407 	/* DO NOT issue DEV_EVENT_STOP directly out of this code */
1408 	/* This can result in INOP of VTAM PU due to halting of  */
1409 	/* outstanding IO which causes a sense to be returned	 */
1410 	/* Only about 3 senses are allowed and then IOS/VTAM will*/
1411 	/* become unreachable without manual intervention	 */
1412 	if ((grp->port_persist == 1) || (grp->alloc_called)) {
1413 		grp->alloc_called = 0;
1414 		fsm_deltimer(&priv->restart_timer);
1415 		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_RESTART, dev);
1416 		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1417 		if (grp->saved_state > MPCG_STATE_XID7INITF)
1418 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
1419 				"%s(%s): MPC GROUP RECOVERY SCHEDULED",
1420 					CTCM_FUNTAIL, dev->name);
1421 	} else {
1422 		fsm_deltimer(&priv->restart_timer);
1423 		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_STOP, dev);
1424 		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1425 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
1426 			"%s(%s): NO MPC GROUP RECOVERY ATTEMPTED",
1427 						CTCM_FUNTAIL, dev->name);
1428 	}
1429 }
1430 
1431 /*
1432  * Handle mpc group  action timeout.
1433  * MPC Group Station FSM action
1434  * CTCM_PROTO_MPC only
1435  *
1436  * fi		An instance of an mpc_group fsm.
1437  * event	The event, just happened.
1438  * arg		Generic pointer, casted from net_device * upon call.
1439  */
mpc_action_timeout(fsm_instance * fi,int event,void * arg)1440 static void mpc_action_timeout(fsm_instance *fi, int event, void *arg)
1441 {
1442 	struct net_device *dev = arg;
1443 	struct ctcm_priv *priv;
1444 	struct mpc_group *grp;
1445 	struct channel *wch;
1446 	struct channel *rch;
1447 
1448 	priv = dev->ml_priv;
1449 	grp = priv->mpcg;
1450 	wch = priv->channel[CTCM_WRITE];
1451 	rch = priv->channel[CTCM_READ];
1452 
1453 	switch (fsm_getstate(grp->fsm)) {
1454 	case MPCG_STATE_XID2INITW:
1455 		/* Unless there is outstanding IO on the  */
1456 		/* channel just return and wait for ATTN  */
1457 		/* interrupt to begin XID negotiations	  */
1458 		if ((fsm_getstate(rch->fsm) == CH_XID0_PENDING) &&
1459 		   (fsm_getstate(wch->fsm) == CH_XID0_PENDING))
1460 			break;
1461 		fallthrough;
1462 	default:
1463 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1464 	}
1465 
1466 	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
1467 			"%s: dev=%s exit",
1468 			CTCM_FUNTAIL, dev->name);
1469 	return;
1470 }
1471 
1472 /*
1473  * MPC Group Station FSM action
1474  * CTCM_PROTO_MPC only
1475  */
mpc_action_discontact(fsm_instance * fi,int event,void * arg)1476 void mpc_action_discontact(fsm_instance *fi, int event, void *arg)
1477 {
1478 	struct mpcg_info   *mpcginfo   = arg;
1479 	struct channel	   *ch	       = mpcginfo->ch;
1480 	struct net_device  *dev;
1481 	struct ctcm_priv   *priv;
1482 	struct mpc_group   *grp;
1483 
1484 	if (ch) {
1485 		dev = ch->netdev;
1486 		if (dev) {
1487 			priv = dev->ml_priv;
1488 			if (priv) {
1489 				CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1490 					"%s: %s: %s\n",
1491 					CTCM_FUNTAIL, dev->name, ch->id);
1492 				grp = priv->mpcg;
1493 				grp->send_qllc_disc = 1;
1494 				fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1495 			}
1496 		}
1497 	}
1498 
1499 	return;
1500 }
1501 
1502 /*
1503  * MPC Group Station - not part of FSM
1504  * CTCM_PROTO_MPC only
1505  * called from add_channel in ctcm_main.c
1506  */
mpc_action_send_discontact(unsigned long thischan)1507 void mpc_action_send_discontact(unsigned long thischan)
1508 {
1509 	int rc;
1510 	struct channel	*ch = (struct channel *)thischan;
1511 	unsigned long	saveflags = 0;
1512 
1513 	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1514 	rc = ccw_device_start(ch->cdev, &ch->ccw[15], 0, 0xff, 0);
1515 	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1516 
1517 	if (rc != 0) {
1518 		ctcm_ccw_check_rc(ch, rc, (char *)__func__);
1519 	}
1520 
1521 	return;
1522 }
1523 
1524 
1525 /*
1526  * helper function of mpc FSM
1527  * CTCM_PROTO_MPC only
1528  * mpc_action_rcvd_xid7
1529 */
mpc_validate_xid(struct mpcg_info * mpcginfo)1530 static int mpc_validate_xid(struct mpcg_info *mpcginfo)
1531 {
1532 	struct channel	   *ch	 = mpcginfo->ch;
1533 	struct net_device  *dev  = ch->netdev;
1534 	struct ctcm_priv   *priv = dev->ml_priv;
1535 	struct mpc_group   *grp  = priv->mpcg;
1536 	struct xid2	   *xid  = mpcginfo->xid;
1537 	int	rc	 = 0;
1538 	__u64	our_id   = 0;
1539 	__u64   their_id = 0;
1540 	int	len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1541 
1542 	CTCM_PR_DEBUG("Enter %s: xid=%p\n", __func__, xid);
1543 
1544 	if (xid == NULL) {
1545 		rc = 1;
1546 		/* XID REJECTED: xid == NULL */
1547 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1548 			"%s(%s): xid = NULL",
1549 				CTCM_FUNTAIL, ch->id);
1550 		goto done;
1551 	}
1552 
1553 	CTCM_D3_DUMP((char *)xid, XID2_LENGTH);
1554 
1555 	/*the received direction should be the opposite of ours  */
1556 	if (((CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ? XID2_WRITE_SIDE :
1557 				XID2_READ_SIDE) != xid->xid2_dlc_type) {
1558 		rc = 2;
1559 		/* XID REJECTED: r/w channel pairing mismatch */
1560 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1561 			"%s(%s): r/w channel pairing mismatch",
1562 				CTCM_FUNTAIL, ch->id);
1563 		goto done;
1564 	}
1565 
1566 	if (xid->xid2_dlc_type == XID2_READ_SIDE) {
1567 		CTCM_PR_DEBUG("%s: grpmaxbuf:%d xid2buflen:%d\n", __func__,
1568 				grp->group_max_buflen, xid->xid2_buf_len);
1569 
1570 		if (grp->group_max_buflen == 0 || grp->group_max_buflen >
1571 						xid->xid2_buf_len - len)
1572 			grp->group_max_buflen = xid->xid2_buf_len - len;
1573 	}
1574 
1575 	if (grp->saved_xid2 == NULL) {
1576 		grp->saved_xid2 =
1577 			(struct xid2 *)skb_tail_pointer(grp->rcvd_xid_skb);
1578 
1579 		skb_put_data(grp->rcvd_xid_skb, xid, XID2_LENGTH);
1580 		grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
1581 
1582 		skb_reset_tail_pointer(grp->rcvd_xid_skb);
1583 		grp->rcvd_xid_skb->len = 0;
1584 
1585 		/* convert two 32 bit numbers into 1 64 bit for id compare */
1586 		our_id = (__u64)priv->xid->xid2_adj_id;
1587 		our_id = our_id << 32;
1588 		our_id = our_id + priv->xid->xid2_sender_id;
1589 		their_id = (__u64)xid->xid2_adj_id;
1590 		their_id = their_id << 32;
1591 		their_id = their_id + xid->xid2_sender_id;
1592 		/* lower id assume the xside role */
1593 		if (our_id < their_id) {
1594 			grp->roll = XSIDE;
1595 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1596 				"%s(%s): WE HAVE LOW ID - TAKE XSIDE",
1597 					CTCM_FUNTAIL, ch->id);
1598 		} else {
1599 			grp->roll = YSIDE;
1600 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1601 				"%s(%s): WE HAVE HIGH ID - TAKE YSIDE",
1602 					CTCM_FUNTAIL, ch->id);
1603 		}
1604 
1605 	} else {
1606 		if (xid->xid2_flag4 != grp->saved_xid2->xid2_flag4) {
1607 			rc = 3;
1608 			/* XID REJECTED: xid flag byte4 mismatch */
1609 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1610 				"%s(%s): xid flag byte4 mismatch",
1611 					CTCM_FUNTAIL, ch->id);
1612 		}
1613 		if (xid->xid2_flag2 == 0x40) {
1614 			rc = 4;
1615 			/* XID REJECTED - xid NOGOOD */
1616 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1617 				"%s(%s): xid NOGOOD",
1618 					CTCM_FUNTAIL, ch->id);
1619 		}
1620 		if (xid->xid2_adj_id != grp->saved_xid2->xid2_adj_id) {
1621 			rc = 5;
1622 			/* XID REJECTED - Adjacent Station ID Mismatch */
1623 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1624 				"%s(%s): Adjacent Station ID Mismatch",
1625 					CTCM_FUNTAIL, ch->id);
1626 		}
1627 		if (xid->xid2_sender_id != grp->saved_xid2->xid2_sender_id) {
1628 			rc = 6;
1629 			/* XID REJECTED - Sender Address Mismatch */
1630 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1631 				"%s(%s): Sender Address Mismatch",
1632 					CTCM_FUNTAIL, ch->id);
1633 		}
1634 	}
1635 done:
1636 	if (rc) {
1637 		dev_warn(&dev->dev,
1638 			"The XID used in the MPC protocol is not valid, "
1639 			"rc = %d\n", rc);
1640 		priv->xid->xid2_flag2 = 0x40;
1641 		grp->saved_xid2->xid2_flag2 = 0x40;
1642 	}
1643 
1644 	return rc;
1645 }
1646 
1647 /*
1648  * MPC Group Station FSM action
1649  * CTCM_PROTO_MPC only
1650  */
mpc_action_side_xid(fsm_instance * fsm,void * arg,int side)1651 static void mpc_action_side_xid(fsm_instance *fsm, void *arg, int side)
1652 {
1653 	struct channel *ch = arg;
1654 	int rc = 0;
1655 	int gotlock = 0;
1656 	unsigned long saveflags = 0;	/* avoids compiler warning with
1657 					   spin_unlock_irqrestore */
1658 
1659 	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
1660 			__func__, smp_processor_id(), ch, ch->id);
1661 
1662 	if (ctcm_checkalloc_buffer(ch))
1663 					goto done;
1664 
1665 	/*
1666 	 * skb data-buffer referencing:
1667 	 */
1668 	ch->trans_skb->data = ch->trans_skb_data;
1669 	skb_reset_tail_pointer(ch->trans_skb);
1670 	ch->trans_skb->len = 0;
1671 	/* result of the previous 3 statements is NOT always
1672 	 * already set after ctcm_checkalloc_buffer
1673 	 * because of possible reuse of the trans_skb
1674 	 */
1675 	memset(ch->trans_skb->data, 0, 16);
1676 	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
1677 	/* check is main purpose here: */
1678 	skb_put(ch->trans_skb, TH_HEADER_LENGTH);
1679 	ch->rcvd_xid = (struct xid2 *)skb_tail_pointer(ch->trans_skb);
1680 	/* check is main purpose here: */
1681 	skb_put(ch->trans_skb, XID2_LENGTH);
1682 	ch->rcvd_xid_id = skb_tail_pointer(ch->trans_skb);
1683 	/* cleanup back to startpoint */
1684 	ch->trans_skb->data = ch->trans_skb_data;
1685 	skb_reset_tail_pointer(ch->trans_skb);
1686 	ch->trans_skb->len = 0;
1687 
1688 	/* non-checking rewrite of above skb data-buffer referencing: */
1689 	/*
1690 	memset(ch->trans_skb->data, 0, 16);
1691 	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
1692 	ch->rcvd_xid = (struct xid2 *)(ch->trans_skb_data + TH_HEADER_LENGTH);
1693 	ch->rcvd_xid_id = ch->trans_skb_data + TH_HEADER_LENGTH + XID2_LENGTH;
1694 	 */
1695 
1696 	ch->ccw[8].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1697 	ch->ccw[8].count	= 0;
1698 	ch->ccw[8].cda		= 0x00;
1699 
1700 	if (!(ch->xid_th && ch->xid && ch->xid_id))
1701 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_INFO,
1702 			"%s(%s): xid_th=%p, xid=%p, xid_id=%p",
1703 			CTCM_FUNTAIL, ch->id, ch->xid_th, ch->xid, ch->xid_id);
1704 
1705 	if (side == XSIDE) {
1706 		/* mpc_action_xside_xid */
1707 		if (ch->xid_th == NULL)
1708 				goto done;
1709 		ch->ccw[9].cmd_code	= CCW_CMD_WRITE;
1710 		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1711 		ch->ccw[9].count	= TH_HEADER_LENGTH;
1712 		ch->ccw[9].cda		= virt_to_dma32(ch->xid_th);
1713 
1714 		if (ch->xid == NULL)
1715 				goto done;
1716 		ch->ccw[10].cmd_code	= CCW_CMD_WRITE;
1717 		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1718 		ch->ccw[10].count	= XID2_LENGTH;
1719 		ch->ccw[10].cda		= virt_to_dma32(ch->xid);
1720 
1721 		ch->ccw[11].cmd_code	= CCW_CMD_READ;
1722 		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1723 		ch->ccw[11].count	= TH_HEADER_LENGTH;
1724 		ch->ccw[11].cda		= virt_to_dma32(ch->rcvd_xid_th);
1725 
1726 		ch->ccw[12].cmd_code	= CCW_CMD_READ;
1727 		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1728 		ch->ccw[12].count	= XID2_LENGTH;
1729 		ch->ccw[12].cda		= virt_to_dma32(ch->rcvd_xid);
1730 
1731 		ch->ccw[13].cmd_code	= CCW_CMD_READ;
1732 		ch->ccw[13].cda		= virt_to_dma32(ch->rcvd_xid_id);
1733 
1734 	} else { /* side == YSIDE : mpc_action_yside_xid */
1735 		ch->ccw[9].cmd_code	= CCW_CMD_READ;
1736 		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1737 		ch->ccw[9].count	= TH_HEADER_LENGTH;
1738 		ch->ccw[9].cda		= virt_to_dma32(ch->rcvd_xid_th);
1739 
1740 		ch->ccw[10].cmd_code	= CCW_CMD_READ;
1741 		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1742 		ch->ccw[10].count	= XID2_LENGTH;
1743 		ch->ccw[10].cda		= virt_to_dma32(ch->rcvd_xid);
1744 
1745 		if (ch->xid_th == NULL)
1746 				goto done;
1747 		ch->ccw[11].cmd_code	= CCW_CMD_WRITE;
1748 		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1749 		ch->ccw[11].count	= TH_HEADER_LENGTH;
1750 		ch->ccw[11].cda		= virt_to_dma32(ch->xid_th);
1751 
1752 		if (ch->xid == NULL)
1753 				goto done;
1754 		ch->ccw[12].cmd_code	= CCW_CMD_WRITE;
1755 		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1756 		ch->ccw[12].count	= XID2_LENGTH;
1757 		ch->ccw[12].cda		= virt_to_dma32(ch->xid);
1758 
1759 		if (ch->xid_id == NULL)
1760 				goto done;
1761 		ch->ccw[13].cmd_code	= CCW_CMD_WRITE;
1762 		ch->ccw[13].cda		= virt_to_dma32(ch->xid_id);
1763 
1764 	}
1765 	ch->ccw[13].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1766 	ch->ccw[13].count	= 4;
1767 
1768 	ch->ccw[14].cmd_code	= CCW_CMD_NOOP;
1769 	ch->ccw[14].flags	= CCW_FLAG_SLI;
1770 	ch->ccw[14].count	= 0;
1771 	ch->ccw[14].cda		= 0;
1772 
1773 	CTCM_CCW_DUMP((char *)&ch->ccw[8], sizeof(struct ccw1) * 7);
1774 	CTCM_D3_DUMP((char *)ch->xid_th, TH_HEADER_LENGTH);
1775 	CTCM_D3_DUMP((char *)ch->xid, XID2_LENGTH);
1776 	CTCM_D3_DUMP((char *)ch->xid_id, 4);
1777 
1778 	if (!in_hardirq()) {
1779 			 /* Such conditional locking is a known problem for
1780 			  * sparse because its static undeterministic.
1781 			  * Warnings should be ignored here. */
1782 		spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1783 		gotlock = 1;
1784 	}
1785 
1786 	fsm_addtimer(&ch->timer, 5000 , CTC_EVENT_TIMER, ch);
1787 	rc = ccw_device_start(ch->cdev, &ch->ccw[8], 0, 0xff, 0);
1788 
1789 	if (gotlock)	/* see remark above about conditional locking */
1790 		spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1791 
1792 	if (rc != 0) {
1793 		ctcm_ccw_check_rc(ch, rc,
1794 				(side == XSIDE) ? "x-side XID" : "y-side XID");
1795 	}
1796 
1797 done:
1798 	CTCM_PR_DEBUG("Exit %s: ch=0x%p id=%s\n",
1799 				__func__, ch, ch->id);
1800 	return;
1801 
1802 }
1803 
1804 /*
1805  * MPC Group Station FSM action
1806  * CTCM_PROTO_MPC only
1807  */
mpc_action_xside_xid(fsm_instance * fsm,int event,void * arg)1808 static void mpc_action_xside_xid(fsm_instance *fsm, int event, void *arg)
1809 {
1810 	mpc_action_side_xid(fsm, arg, XSIDE);
1811 }
1812 
1813 /*
1814  * MPC Group Station FSM action
1815  * CTCM_PROTO_MPC only
1816  */
mpc_action_yside_xid(fsm_instance * fsm,int event,void * arg)1817 static void mpc_action_yside_xid(fsm_instance *fsm, int event, void *arg)
1818 {
1819 	mpc_action_side_xid(fsm, arg, YSIDE);
1820 }
1821 
1822 /*
1823  * MPC Group Station FSM action
1824  * CTCM_PROTO_MPC only
1825  */
mpc_action_doxid0(fsm_instance * fsm,int event,void * arg)1826 static void mpc_action_doxid0(fsm_instance *fsm, int event, void *arg)
1827 {
1828 	struct channel	   *ch   = arg;
1829 	struct net_device  *dev  = ch->netdev;
1830 	struct ctcm_priv   *priv = dev->ml_priv;
1831 	struct mpc_group   *grp  = priv->mpcg;
1832 
1833 	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
1834 			__func__, smp_processor_id(), ch, ch->id);
1835 
1836 	if (ch->xid == NULL) {
1837 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1838 			"%s(%s): ch->xid == NULL",
1839 				CTCM_FUNTAIL, dev->name);
1840 		return;
1841 	}
1842 
1843 	fsm_newstate(ch->fsm, CH_XID0_INPROGRESS);
1844 
1845 	ch->xid->xid2_option =	XID2_0;
1846 
1847 	switch (fsm_getstate(grp->fsm)) {
1848 	case MPCG_STATE_XID2INITW:
1849 	case MPCG_STATE_XID2INITX:
1850 		ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1851 		break;
1852 	case MPCG_STATE_XID0IOWAIT:
1853 	case MPCG_STATE_XID0IOWAIX:
1854 		ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1855 		break;
1856 	}
1857 
1858 	fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
1859 
1860 	return;
1861 }
1862 
1863 /*
1864  * MPC Group Station FSM action
1865  * CTCM_PROTO_MPC only
1866 */
mpc_action_doxid7(fsm_instance * fsm,int event,void * arg)1867 static void mpc_action_doxid7(fsm_instance *fsm, int event, void *arg)
1868 {
1869 	struct net_device *dev = arg;
1870 	struct ctcm_priv  *priv = dev->ml_priv;
1871 	struct mpc_group  *grp  = NULL;
1872 	int direction;
1873 	int send = 0;
1874 
1875 	if (priv)
1876 		grp = priv->mpcg;
1877 	if (grp == NULL)
1878 		return;
1879 
1880 	for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1881 		struct channel *ch = priv->channel[direction];
1882 		struct xid2 *thisxid = ch->xid;
1883 		ch->xid_skb->data = ch->xid_skb_data;
1884 		skb_reset_tail_pointer(ch->xid_skb);
1885 		ch->xid_skb->len = 0;
1886 		thisxid->xid2_option = XID2_7;
1887 		send = 0;
1888 
1889 		/* xid7 phase 1 */
1890 		if (grp->outstanding_xid7_p2 > 0) {
1891 			if (grp->roll == YSIDE) {
1892 				if (fsm_getstate(ch->fsm) == CH_XID7_PENDING1) {
1893 					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
1894 					ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1895 					skb_put_data(ch->xid_skb, &thdummy,
1896 						     TH_HEADER_LENGTH);
1897 					send = 1;
1898 				}
1899 			} else if (fsm_getstate(ch->fsm) < CH_XID7_PENDING2) {
1900 					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
1901 					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1902 					skb_put_data(ch->xid_skb, &thnorm,
1903 						     TH_HEADER_LENGTH);
1904 					send = 1;
1905 			}
1906 		} else {
1907 			/* xid7 phase 2 */
1908 			if (grp->roll == YSIDE) {
1909 				if (fsm_getstate(ch->fsm) < CH_XID7_PENDING4) {
1910 					fsm_newstate(ch->fsm, CH_XID7_PENDING4);
1911 					skb_put_data(ch->xid_skb, &thnorm,
1912 						     TH_HEADER_LENGTH);
1913 					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1914 					send = 1;
1915 				}
1916 			} else if (fsm_getstate(ch->fsm) == CH_XID7_PENDING3) {
1917 				fsm_newstate(ch->fsm, CH_XID7_PENDING4);
1918 				ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1919 				skb_put_data(ch->xid_skb, &thdummy,
1920 					     TH_HEADER_LENGTH);
1921 				send = 1;
1922 			}
1923 		}
1924 
1925 		if (send)
1926 			fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
1927 	}
1928 
1929 	return;
1930 }
1931 
1932 /*
1933  * MPC Group Station FSM action
1934  * CTCM_PROTO_MPC only
1935  */
mpc_action_rcvd_xid0(fsm_instance * fsm,int event,void * arg)1936 static void mpc_action_rcvd_xid0(fsm_instance *fsm, int event, void *arg)
1937 {
1938 
1939 	struct mpcg_info   *mpcginfo  = arg;
1940 	struct channel	   *ch   = mpcginfo->ch;
1941 	struct net_device  *dev  = ch->netdev;
1942 	struct ctcm_priv   *priv = dev->ml_priv;
1943 	struct mpc_group   *grp  = priv->mpcg;
1944 
1945 	CTCM_PR_DEBUG("%s: ch-id:%s xid2:%i xid7:%i xidt_p2:%i \n",
1946 			__func__, ch->id, grp->outstanding_xid2,
1947 			grp->outstanding_xid7, grp->outstanding_xid7_p2);
1948 
1949 	if (fsm_getstate(ch->fsm) < CH_XID7_PENDING)
1950 		fsm_newstate(ch->fsm, CH_XID7_PENDING);
1951 
1952 	grp->outstanding_xid2--;
1953 	grp->outstanding_xid7++;
1954 	grp->outstanding_xid7_p2++;
1955 
1956 	/* must change state before validating xid to */
1957 	/* properly handle interim interrupts received*/
1958 	switch (fsm_getstate(grp->fsm)) {
1959 	case MPCG_STATE_XID2INITW:
1960 		fsm_newstate(grp->fsm, MPCG_STATE_XID2INITX);
1961 		mpc_validate_xid(mpcginfo);
1962 		break;
1963 	case MPCG_STATE_XID0IOWAIT:
1964 		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIX);
1965 		mpc_validate_xid(mpcginfo);
1966 		break;
1967 	case MPCG_STATE_XID2INITX:
1968 		if (grp->outstanding_xid2 == 0) {
1969 			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITW);
1970 			mpc_validate_xid(mpcginfo);
1971 			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
1972 		}
1973 		break;
1974 	case MPCG_STATE_XID0IOWAIX:
1975 		if (grp->outstanding_xid2 == 0) {
1976 			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITI);
1977 			mpc_validate_xid(mpcginfo);
1978 			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
1979 		}
1980 		break;
1981 	}
1982 
1983 	CTCM_PR_DEBUG("ctcmpc:%s() %s xid2:%i xid7:%i xidt_p2:%i \n",
1984 		__func__, ch->id, grp->outstanding_xid2,
1985 		grp->outstanding_xid7, grp->outstanding_xid7_p2);
1986 	CTCM_PR_DEBUG("ctcmpc:%s() %s grpstate: %s chanstate: %s \n",
1987 		__func__, ch->id,
1988 		fsm_getstate_str(grp->fsm), fsm_getstate_str(ch->fsm));
1989 	return;
1990 
1991 }
1992 
1993 
1994 /*
1995  * MPC Group Station FSM action
1996  * CTCM_PROTO_MPC only
1997  */
mpc_action_rcvd_xid7(fsm_instance * fsm,int event,void * arg)1998 static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg)
1999 {
2000 	struct mpcg_info   *mpcginfo   = arg;
2001 	struct channel	   *ch	       = mpcginfo->ch;
2002 	struct net_device  *dev        = ch->netdev;
2003 	struct ctcm_priv   *priv    = dev->ml_priv;
2004 	struct mpc_group   *grp     = priv->mpcg;
2005 
2006 	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
2007 		__func__, smp_processor_id(), ch, ch->id);
2008 	CTCM_PR_DEBUG("%s: outstanding_xid7: %i, outstanding_xid7_p2: %i\n",
2009 		__func__, grp->outstanding_xid7, grp->outstanding_xid7_p2);
2010 
2011 	grp->outstanding_xid7--;
2012 	ch->xid_skb->data = ch->xid_skb_data;
2013 	skb_reset_tail_pointer(ch->xid_skb);
2014 	ch->xid_skb->len = 0;
2015 
2016 	switch (fsm_getstate(grp->fsm)) {
2017 	case MPCG_STATE_XID7INITI:
2018 		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITZ);
2019 		mpc_validate_xid(mpcginfo);
2020 		break;
2021 	case MPCG_STATE_XID7INITW:
2022 		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITX);
2023 		mpc_validate_xid(mpcginfo);
2024 		break;
2025 	case MPCG_STATE_XID7INITZ:
2026 	case MPCG_STATE_XID7INITX:
2027 		if (grp->outstanding_xid7 == 0) {
2028 			if (grp->outstanding_xid7_p2 > 0) {
2029 				grp->outstanding_xid7 =
2030 					grp->outstanding_xid7_p2;
2031 				grp->outstanding_xid7_p2 = 0;
2032 			} else
2033 				fsm_newstate(grp->fsm, MPCG_STATE_XID7INITF);
2034 
2035 			mpc_validate_xid(mpcginfo);
2036 			fsm_event(grp->fsm, MPCG_EVENT_XID7DONE, dev);
2037 			break;
2038 		}
2039 		mpc_validate_xid(mpcginfo);
2040 		break;
2041 	}
2042 	return;
2043 }
2044 
2045 /*
2046  * mpc_action helper of an MPC Group Station FSM action
2047  * CTCM_PROTO_MPC only
2048  */
mpc_send_qllc_discontact(struct net_device * dev)2049 static int mpc_send_qllc_discontact(struct net_device *dev)
2050 {
2051 	struct sk_buff   *skb;
2052 	struct qllc      *qllcptr;
2053 	struct ctcm_priv *priv = dev->ml_priv;
2054 	struct mpc_group *grp = priv->mpcg;
2055 
2056 	CTCM_PR_DEBUG("%s: GROUP STATE: %s\n",
2057 		__func__, mpcg_state_names[grp->saved_state]);
2058 
2059 	switch (grp->saved_state) {
2060 	/*
2061 	 * establish conn callback function is
2062 	 * preferred method to report failure
2063 	 */
2064 	case MPCG_STATE_XID0IOWAIT:
2065 	case MPCG_STATE_XID0IOWAIX:
2066 	case MPCG_STATE_XID7INITI:
2067 	case MPCG_STATE_XID7INITZ:
2068 	case MPCG_STATE_XID2INITW:
2069 	case MPCG_STATE_XID2INITX:
2070 	case MPCG_STATE_XID7INITW:
2071 	case MPCG_STATE_XID7INITX:
2072 		if (grp->estconnfunc) {
2073 			grp->estconnfunc(grp->port_num, -1, 0);
2074 			grp->estconnfunc = NULL;
2075 			break;
2076 		}
2077 		fallthrough;
2078 	case MPCG_STATE_FLOWC:
2079 	case MPCG_STATE_READY:
2080 		grp->send_qllc_disc = 2;
2081 
2082 		skb = __dev_alloc_skb(sizeof(struct qllc), GFP_ATOMIC);
2083 		if (skb == NULL) {
2084 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2085 				"%s(%s): skb allocation error",
2086 						CTCM_FUNTAIL, dev->name);
2087 			priv->stats.rx_dropped++;
2088 			return -ENOMEM;
2089 		}
2090 
2091 		qllcptr = skb_put(skb, sizeof(struct qllc));
2092 		qllcptr->qllc_address = 0xcc;
2093 		qllcptr->qllc_commands = 0x03;
2094 
2095 		if (skb_headroom(skb) < 4) {
2096 			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2097 				"%s(%s): skb_headroom error",
2098 						CTCM_FUNTAIL, dev->name);
2099 			dev_kfree_skb_any(skb);
2100 			return -ENOMEM;
2101 		}
2102 
2103 		*((__u32 *)skb_push(skb, 4)) =
2104 			priv->channel[CTCM_READ]->pdu_seq;
2105 		priv->channel[CTCM_READ]->pdu_seq++;
2106 		CTCM_PR_DBGDATA("ctcmpc: %s ToDCM_pdu_seq= %08x\n",
2107 				__func__, priv->channel[CTCM_READ]->pdu_seq);
2108 
2109 		/* receipt of CC03 resets anticipated sequence number on
2110 		      receiving side */
2111 		priv->channel[CTCM_READ]->pdu_seq = 0x00;
2112 		skb_reset_mac_header(skb);
2113 		skb->dev = dev;
2114 		skb->protocol = htons(ETH_P_SNAP);
2115 		skb->ip_summed = CHECKSUM_UNNECESSARY;
2116 
2117 		CTCM_D3_DUMP(skb->data, (sizeof(struct qllc) + 4));
2118 
2119 		netif_rx(skb);
2120 		break;
2121 	default:
2122 		break;
2123 
2124 	}
2125 
2126 	return 0;
2127 }
2128 /* --- This is the END my friend --- */
2129 
2130