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
59static 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
82static 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
90static 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
107static void ctcmpc_unpack_skb(struct channel *ch, struct sk_buff *pskb);
108
109/*
110 * MPC Group state machine actions (static prototypes)
111 */
112static void mpc_action_nop(fsm_instance *fsm, int event, void *arg);
113static void mpc_action_go_ready(fsm_instance *fsm, int event, void *arg);
114static void mpc_action_go_inop(fsm_instance *fi, int event, void *arg);
115static void mpc_action_timeout(fsm_instance *fi, int event, void *arg);
116static int  mpc_validate_xid(struct mpcg_info *mpcginfo);
117static void mpc_action_yside_xid(fsm_instance *fsm, int event, void *arg);
118static void mpc_action_doxid0(fsm_instance *fsm, int event, void *arg);
119static void mpc_action_doxid7(fsm_instance *fsm, int event, void *arg);
120static void mpc_action_xside_xid(fsm_instance *fsm, int event, void *arg);
121static void mpc_action_rcvd_xid0(fsm_instance *fsm, int event, void *arg);
122static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg);
123
124#ifdef DEBUGDATA
125/*-------------------------------------------------------------------*
126* Dump buffer format						     *
127*								     *
128*--------------------------------------------------------------------*/
129void 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 */
228void 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
269dumpth:
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	}
278dumpdata:
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
288static 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 */
327int ctc_mpc_alloc_channel(int port_num, void (*callback)(int, int))
328{
329	struct net_device *dev;
330	struct mpc_group *grp;
331	struct ctcm_priv *priv;
332
333	dev = ctcmpc_get_dev(port_num);
334	if (dev == NULL)
335		return 1;
336	priv = dev->ml_priv;
337	grp = priv->mpcg;
338
339	grp->allochanfunc = callback;
340	grp->port_num = port_num;
341	grp->port_persist = 1;
342
343	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
344			"%s(%s): state=%s",
345			CTCM_FUNTAIL, dev->name, fsm_getstate_str(grp->fsm));
346
347	switch (fsm_getstate(grp->fsm)) {
348	case MPCG_STATE_INOP:
349		/* Group is in the process of terminating */
350		grp->alloc_called = 1;
351		break;
352	case MPCG_STATE_RESET:
353		/* MPC Group will transition to state		  */
354		/* MPCG_STATE_XID2INITW iff the minimum number	  */
355		/* of 1 read and 1 write channel have successfully*/
356		/* activated					  */
357		/*fsm_newstate(grp->fsm, MPCG_STATE_XID2INITW);*/
358		if (callback)
359			grp->send_qllc_disc = 1;
360		fallthrough;
361	case MPCG_STATE_XID0IOWAIT:
362		fsm_deltimer(&grp->timer);
363		grp->outstanding_xid2 = 0;
364		grp->outstanding_xid7 = 0;
365		grp->outstanding_xid7_p2 = 0;
366		grp->saved_xid2 = NULL;
367		if (callback)
368			ctcm_open(dev);
369		fsm_event(priv->fsm, DEV_EVENT_START, dev);
370		break;
371	case MPCG_STATE_READY:
372		/* XID exchanges completed after PORT was activated */
373		/* Link station already active			    */
374		/* Maybe timing issue...retry callback		    */
375		grp->allocchan_callback_retries++;
376		if (grp->allocchan_callback_retries < 4) {
377			if (grp->allochanfunc)
378				grp->allochanfunc(grp->port_num,
379						  grp->group_max_buflen);
380		} else {
381			/* there are problems...bail out	    */
382			/* there may be a state mismatch so restart */
383			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
384			grp->allocchan_callback_retries = 0;
385		}
386		break;
387	}
388
389	return 0;
390}
391EXPORT_SYMBOL(ctc_mpc_alloc_channel);
392
393/*
394 * ctc_mpc_establish_connectivity
395 *	(exported interface)
396 */
397void ctc_mpc_establish_connectivity(int port_num,
398				void (*callback)(int, int, int))
399{
400	struct net_device *dev;
401	struct mpc_group *grp;
402	struct ctcm_priv *priv;
403	struct channel *rch, *wch;
404
405	dev = ctcmpc_get_dev(port_num);
406	if (dev == NULL)
407		return;
408	priv = dev->ml_priv;
409	grp = priv->mpcg;
410	rch = priv->channel[CTCM_READ];
411	wch = priv->channel[CTCM_WRITE];
412
413	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
414			"%s(%s): state=%s",
415			CTCM_FUNTAIL, dev->name, fsm_getstate_str(grp->fsm));
416
417	grp->estconnfunc = callback;
418	grp->port_num = port_num;
419
420	switch (fsm_getstate(grp->fsm)) {
421	case MPCG_STATE_READY:
422		/* XID exchanges completed after PORT was activated */
423		/* Link station already active			    */
424		/* Maybe timing issue...retry callback		    */
425		fsm_deltimer(&grp->timer);
426		grp->estconn_callback_retries++;
427		if (grp->estconn_callback_retries < 4) {
428			if (grp->estconnfunc) {
429				grp->estconnfunc(grp->port_num, 0,
430						grp->group_max_buflen);
431				grp->estconnfunc = NULL;
432			}
433		} else {
434			/* there are problems...bail out	 */
435			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
436			grp->estconn_callback_retries = 0;
437		}
438		break;
439	case MPCG_STATE_INOP:
440	case MPCG_STATE_RESET:
441		/* MPC Group is not ready to start XID - min num of */
442		/* 1 read and 1 write channel have not been acquired*/
443
444		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
445			"%s(%s): REJECTED - inactive channels",
446					CTCM_FUNTAIL, dev->name);
447		if (grp->estconnfunc) {
448			grp->estconnfunc(grp->port_num, -1, 0);
449			grp->estconnfunc = NULL;
450		}
451		break;
452	case MPCG_STATE_XID2INITW:
453		/* alloc channel was called but no XID exchange    */
454		/* has occurred. initiate xside XID exchange	   */
455		/* make sure yside XID0 processing has not started */
456
457		if ((fsm_getstate(rch->fsm) > CH_XID0_PENDING) ||
458			(fsm_getstate(wch->fsm) > CH_XID0_PENDING)) {
459			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
460				"%s(%s): ABORT - PASSIVE XID",
461					CTCM_FUNTAIL, dev->name);
462			break;
463		}
464		grp->send_qllc_disc = 1;
465		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIT);
466		fsm_deltimer(&grp->timer);
467		fsm_addtimer(&grp->timer, MPC_XID_TIMEOUT_VALUE,
468						MPCG_EVENT_TIMER, dev);
469		grp->outstanding_xid7 = 0;
470		grp->outstanding_xid7_p2 = 0;
471		grp->saved_xid2 = NULL;
472		if ((rch->in_mpcgroup) &&
473				(fsm_getstate(rch->fsm) == CH_XID0_PENDING))
474			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, rch);
475		else {
476			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
477				"%s(%s): RX-%s not ready for ACTIVE XID0",
478					CTCM_FUNTAIL, dev->name, rch->id);
479			if (grp->estconnfunc) {
480				grp->estconnfunc(grp->port_num, -1, 0);
481				grp->estconnfunc = NULL;
482			}
483			fsm_deltimer(&grp->timer);
484				goto done;
485		}
486		if ((wch->in_mpcgroup) &&
487				(fsm_getstate(wch->fsm) == CH_XID0_PENDING))
488			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, wch);
489		else {
490			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
491				"%s(%s): WX-%s not ready for ACTIVE XID0",
492					CTCM_FUNTAIL, dev->name, wch->id);
493			if (grp->estconnfunc) {
494				grp->estconnfunc(grp->port_num, -1, 0);
495				grp->estconnfunc = NULL;
496			}
497			fsm_deltimer(&grp->timer);
498				goto done;
499			}
500		break;
501	case MPCG_STATE_XID0IOWAIT:
502		/* already in active XID negotiations */
503	default:
504		break;
505	}
506
507done:
508	CTCM_PR_DEBUG("Exit %s()\n", __func__);
509	return;
510}
511EXPORT_SYMBOL(ctc_mpc_establish_connectivity);
512
513/*
514 * ctc_mpc_dealloc_ch
515 *	(exported interface)
516 */
517void ctc_mpc_dealloc_ch(int port_num)
518{
519	struct net_device *dev;
520	struct ctcm_priv *priv;
521	struct mpc_group *grp;
522
523	dev = ctcmpc_get_dev(port_num);
524	if (dev == NULL)
525		return;
526	priv = dev->ml_priv;
527	grp = priv->mpcg;
528
529	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_DEBUG,
530			"%s: %s: refcount = %d\n",
531			CTCM_FUNTAIL, dev->name, netdev_refcnt_read(dev));
532
533	fsm_deltimer(&priv->restart_timer);
534	grp->channels_terminating = 0;
535	fsm_deltimer(&grp->timer);
536	grp->allochanfunc = NULL;
537	grp->estconnfunc = NULL;
538	grp->port_persist = 0;
539	grp->send_qllc_disc = 0;
540	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
541
542	ctcm_close(dev);
543	return;
544}
545EXPORT_SYMBOL(ctc_mpc_dealloc_ch);
546
547/*
548 * ctc_mpc_flow_control
549 *	(exported interface)
550 */
551void ctc_mpc_flow_control(int port_num, int flowc)
552{
553	struct ctcm_priv *priv;
554	struct mpc_group *grp;
555	struct net_device *dev;
556	struct channel *rch;
557	int mpcg_state;
558
559	dev = ctcmpc_get_dev(port_num);
560	if (dev == NULL)
561		return;
562	priv = dev->ml_priv;
563	grp = priv->mpcg;
564
565	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
566			"%s: %s: flowc = %d",
567				CTCM_FUNTAIL, dev->name, flowc);
568
569	rch = priv->channel[CTCM_READ];
570
571	mpcg_state = fsm_getstate(grp->fsm);
572	switch (flowc) {
573	case 1:
574		if (mpcg_state == MPCG_STATE_FLOWC)
575			break;
576		if (mpcg_state == MPCG_STATE_READY) {
577			if (grp->flow_off_called == 1)
578				grp->flow_off_called = 0;
579			else
580				fsm_newstate(grp->fsm, MPCG_STATE_FLOWC);
581			break;
582		}
583		break;
584	case 0:
585		if (mpcg_state == MPCG_STATE_FLOWC) {
586			fsm_newstate(grp->fsm, MPCG_STATE_READY);
587			/* ensure any data that has accumulated */
588			/* on the io_queue will now be sen t	*/
589			tasklet_schedule(&rch->ch_tasklet);
590		}
591		/* possible race condition			*/
592		if (mpcg_state == MPCG_STATE_READY) {
593			grp->flow_off_called = 1;
594			break;
595		}
596		break;
597	}
598
599}
600EXPORT_SYMBOL(ctc_mpc_flow_control);
601
602static int mpc_send_qllc_discontact(struct net_device *);
603
604/*
605 * helper function of ctcmpc_unpack_skb
606*/
607static void mpc_rcvd_sweep_resp(struct mpcg_info *mpcginfo)
608{
609	struct channel	  *rch = mpcginfo->ch;
610	struct net_device *dev = rch->netdev;
611	struct ctcm_priv   *priv = dev->ml_priv;
612	struct mpc_group  *grp = priv->mpcg;
613	struct channel	  *ch = priv->channel[CTCM_WRITE];
614
615	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, ch, ch->id);
616	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
617
618	grp->sweep_rsp_pend_num--;
619
620	if ((grp->sweep_req_pend_num == 0) &&
621			(grp->sweep_rsp_pend_num == 0)) {
622		fsm_deltimer(&ch->sweep_timer);
623		grp->in_sweep = 0;
624		rch->th_seq_num = 0x00;
625		ch->th_seq_num = 0x00;
626		ctcm_clear_busy_do(dev);
627	}
628
629	return;
630
631}
632
633/*
634 * helper function of mpc_rcvd_sweep_req
635 * which is a helper of ctcmpc_unpack_skb
636 */
637static void ctcmpc_send_sweep_resp(struct channel *rch)
638{
639	struct net_device *dev = rch->netdev;
640	struct ctcm_priv *priv = dev->ml_priv;
641	struct mpc_group *grp = priv->mpcg;
642	struct th_sweep *header;
643	struct sk_buff *sweep_skb;
644	struct channel *ch  = priv->channel[CTCM_WRITE];
645
646	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, rch, rch->id);
647
648	sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
649	if (sweep_skb == NULL) {
650		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
651			"%s(%s): sweep_skb allocation ERROR\n",
652			CTCM_FUNTAIL, rch->id);
653		goto done;
654	}
655
656	header = kmalloc(sizeof(struct th_sweep), gfp_type());
657
658	if (!header) {
659		dev_kfree_skb_any(sweep_skb);
660		goto done;
661	}
662
663	header->th.th_seg	= 0x00 ;
664	header->th.th_ch_flag	= TH_SWEEP_RESP;
665	header->th.th_blk_flag	= 0x00;
666	header->th.th_is_xid	= 0x00;
667	header->th.th_seq_num	= 0x00;
668	header->sw.th_last_seq	= ch->th_seq_num;
669
670	skb_put_data(sweep_skb, header, TH_SWEEP_LENGTH);
671
672	kfree(header);
673
674	netif_trans_update(dev);
675	skb_queue_tail(&ch->sweep_queue, sweep_skb);
676
677	fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
678
679	return;
680
681done:
682	grp->in_sweep = 0;
683	ctcm_clear_busy_do(dev);
684	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
685
686	return;
687}
688
689/*
690 * helper function of ctcmpc_unpack_skb
691 */
692static void mpc_rcvd_sweep_req(struct mpcg_info *mpcginfo)
693{
694	struct channel	  *rch     = mpcginfo->ch;
695	struct net_device *dev     = rch->netdev;
696	struct ctcm_priv  *priv = dev->ml_priv;
697	struct mpc_group  *grp  = priv->mpcg;
698	struct channel	  *ch	   = priv->channel[CTCM_WRITE];
699
700	if (do_debug)
701		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
702			" %s(): ch=0x%p id=%s\n", __func__, ch, ch->id);
703
704	if (grp->in_sweep == 0) {
705		grp->in_sweep = 1;
706		ctcm_test_and_set_busy(dev);
707		grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
708		grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
709	}
710
711	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
712
713	grp->sweep_req_pend_num--;
714	ctcmpc_send_sweep_resp(ch);
715	kfree(mpcginfo);
716	return;
717}
718
719/*
720  * MPC Group Station FSM definitions
721 */
722static const char *mpcg_event_names[] = {
723	[MPCG_EVENT_INOP]	= "INOP Condition",
724	[MPCG_EVENT_DISCONC]	= "Discontact Received",
725	[MPCG_EVENT_XID0DO]	= "Channel Active - Start XID",
726	[MPCG_EVENT_XID2]	= "XID2 Received",
727	[MPCG_EVENT_XID2DONE]	= "XID0 Complete",
728	[MPCG_EVENT_XID7DONE]	= "XID7 Complete",
729	[MPCG_EVENT_TIMER]	= "XID Setup Timer",
730	[MPCG_EVENT_DOIO]	= "XID DoIO",
731};
732
733static const char *mpcg_state_names[] = {
734	[MPCG_STATE_RESET]	= "Reset",
735	[MPCG_STATE_INOP]	= "INOP",
736	[MPCG_STATE_XID2INITW]	= "Passive XID- XID0 Pending Start",
737	[MPCG_STATE_XID2INITX]	= "Passive XID- XID0 Pending Complete",
738	[MPCG_STATE_XID7INITW]	= "Passive XID- XID7 Pending P1 Start",
739	[MPCG_STATE_XID7INITX]	= "Passive XID- XID7 Pending P2 Complete",
740	[MPCG_STATE_XID0IOWAIT]	= "Active  XID- XID0 Pending Start",
741	[MPCG_STATE_XID0IOWAIX]	= "Active  XID- XID0 Pending Complete",
742	[MPCG_STATE_XID7INITI]	= "Active  XID- XID7 Pending Start",
743	[MPCG_STATE_XID7INITZ]	= "Active  XID- XID7 Pending Complete ",
744	[MPCG_STATE_XID7INITF]	= "XID        - XID7 Complete ",
745	[MPCG_STATE_FLOWC]	= "FLOW CONTROL ON",
746	[MPCG_STATE_READY]	= "READY",
747};
748
749/*
750 * The MPC Group Station FSM
751 *   22 events
752 */
753static const fsm_node mpcg_fsm[] = {
754	{ MPCG_STATE_RESET,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
755	{ MPCG_STATE_INOP,	MPCG_EVENT_INOP,	mpc_action_nop        },
756	{ MPCG_STATE_FLOWC,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
757
758	{ MPCG_STATE_READY,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
759	{ MPCG_STATE_READY,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
760
761	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
762	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
763	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
764	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
765	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
766
767	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
768	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
769	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
770	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
771	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
772
773	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
774	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
775	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
776	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
777	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
778	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
779	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
780
781	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
782	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
783	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
784	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
785	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
786	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
787
788	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
789	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DISCONC,	mpc_action_discontact },
790	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
791	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_INOP,	mpc_action_go_inop    },
792	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_TIMER,	mpc_action_timeout    },
793	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
794
795	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
796	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DISCONC,	mpc_action_discontact },
797	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
798	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_INOP,	mpc_action_go_inop    },
799	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_TIMER,	mpc_action_timeout    },
800	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
801
802	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
803	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
804	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
805	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
806	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
807	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
808	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
809
810	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
811	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
812	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
813	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
814	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
815	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
816
817	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
818	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_XID7DONE,	mpc_action_go_ready   },
819};
820
821static int mpcg_fsm_len = ARRAY_SIZE(mpcg_fsm);
822
823/*
824 * MPC Group Station FSM action
825 * CTCM_PROTO_MPC only
826 */
827static void mpc_action_go_ready(fsm_instance *fsm, int event, void *arg)
828{
829	struct net_device *dev = arg;
830	struct ctcm_priv *priv = dev->ml_priv;
831	struct mpc_group *grp = priv->mpcg;
832
833	if (grp == NULL) {
834		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
835			"%s(%s): No MPC group",
836				CTCM_FUNTAIL, dev->name);
837		return;
838	}
839
840	fsm_deltimer(&grp->timer);
841
842	if (grp->saved_xid2->xid2_flag2 == 0x40) {
843		priv->xid->xid2_flag2 = 0x00;
844		if (grp->estconnfunc) {
845			grp->estconnfunc(grp->port_num, 1,
846					grp->group_max_buflen);
847			grp->estconnfunc = NULL;
848		} else if (grp->allochanfunc)
849			grp->send_qllc_disc = 1;
850
851		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
852		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
853				"%s(%s): fails",
854					CTCM_FUNTAIL, dev->name);
855		return;
856	}
857
858	grp->port_persist = 1;
859	grp->out_of_sequence = 0;
860	grp->estconn_called = 0;
861
862	tasklet_hi_schedule(&grp->mpc_tasklet2);
863
864	return;
865}
866
867/*
868 * helper of ctcm_init_netdevice
869 * CTCM_PROTO_MPC only
870 */
871void mpc_group_ready(unsigned long adev)
872{
873	struct net_device *dev = (struct net_device *)adev;
874	struct ctcm_priv *priv = dev->ml_priv;
875	struct mpc_group *grp = priv->mpcg;
876	struct channel *ch = NULL;
877
878	if (grp == NULL) {
879		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
880			"%s(%s): No MPC group",
881				CTCM_FUNTAIL, dev->name);
882		return;
883	}
884
885	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
886		"%s: %s: GROUP TRANSITIONED TO READY, maxbuf = %d\n",
887			CTCM_FUNTAIL, dev->name, grp->group_max_buflen);
888
889	fsm_newstate(grp->fsm, MPCG_STATE_READY);
890
891	/* Put up a read on the channel */
892	ch = priv->channel[CTCM_READ];
893	ch->pdu_seq = 0;
894	CTCM_PR_DBGDATA("ctcmpc: %s() ToDCM_pdu_seq= %08x\n" ,
895			__func__, ch->pdu_seq);
896
897	ctcmpc_chx_rxidle(ch->fsm, CTC_EVENT_START, ch);
898	/* Put the write channel in idle state */
899	ch = priv->channel[CTCM_WRITE];
900	if (ch->collect_len > 0) {
901		spin_lock(&ch->collect_lock);
902		ctcm_purge_skb_queue(&ch->collect_queue);
903		ch->collect_len = 0;
904		spin_unlock(&ch->collect_lock);
905	}
906	ctcm_chx_txidle(ch->fsm, CTC_EVENT_START, ch);
907	ctcm_clear_busy(dev);
908
909	if (grp->estconnfunc) {
910		grp->estconnfunc(grp->port_num, 0,
911				    grp->group_max_buflen);
912		grp->estconnfunc = NULL;
913	} else 	if (grp->allochanfunc)
914		grp->allochanfunc(grp->port_num, grp->group_max_buflen);
915
916	grp->send_qllc_disc = 1;
917	grp->changed_side = 0;
918
919	return;
920
921}
922
923/*
924 * Increment the MPC Group Active Channel Counts
925 * helper of dev_action (called from channel fsm)
926 */
927void mpc_channel_action(struct channel *ch, int direction, int action)
928{
929	struct net_device  *dev  = ch->netdev;
930	struct ctcm_priv   *priv = dev->ml_priv;
931	struct mpc_group   *grp  = priv->mpcg;
932
933	if (grp == NULL) {
934		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
935			"%s(%s): No MPC group",
936				CTCM_FUNTAIL, dev->name);
937		return;
938	}
939
940	CTCM_PR_DEBUG("enter %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
941
942	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
943		"%s: %i / Grp:%s total_channels=%i, active_channels: "
944		"read=%i, write=%i\n", __func__, action,
945		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
946		grp->active_channels[CTCM_READ],
947		grp->active_channels[CTCM_WRITE]);
948
949	if ((action == MPC_CHANNEL_ADD) && (ch->in_mpcgroup == 0)) {
950		grp->num_channel_paths++;
951		grp->active_channels[direction]++;
952		grp->outstanding_xid2++;
953		ch->in_mpcgroup = 1;
954
955		if (ch->xid_skb != NULL)
956			dev_kfree_skb_any(ch->xid_skb);
957
958		ch->xid_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT,
959					GFP_ATOMIC | GFP_DMA);
960		if (ch->xid_skb == NULL) {
961			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
962				"%s(%s): Couldn't alloc ch xid_skb\n",
963				CTCM_FUNTAIL, dev->name);
964			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
965			return;
966		}
967		ch->xid_skb_data = ch->xid_skb->data;
968		ch->xid_th = (struct th_header *)ch->xid_skb->data;
969		skb_put(ch->xid_skb, TH_HEADER_LENGTH);
970		ch->xid = (struct xid2 *)skb_tail_pointer(ch->xid_skb);
971		skb_put(ch->xid_skb, XID2_LENGTH);
972		ch->xid_id = skb_tail_pointer(ch->xid_skb);
973		ch->xid_skb->data = ch->xid_skb_data;
974		skb_reset_tail_pointer(ch->xid_skb);
975		ch->xid_skb->len = 0;
976
977		skb_put_data(ch->xid_skb, grp->xid_skb->data,
978			     grp->xid_skb->len);
979
980		ch->xid->xid2_dlc_type =
981			((CHANNEL_DIRECTION(ch->flags) == CTCM_READ)
982				? XID2_READ_SIDE : XID2_WRITE_SIDE);
983
984		if (CHANNEL_DIRECTION(ch->flags) == CTCM_WRITE)
985			ch->xid->xid2_buf_len = 0x00;
986
987		ch->xid_skb->data = ch->xid_skb_data;
988		skb_reset_tail_pointer(ch->xid_skb);
989		ch->xid_skb->len = 0;
990
991		fsm_newstate(ch->fsm, CH_XID0_PENDING);
992
993		if ((grp->active_channels[CTCM_READ] > 0) &&
994		    (grp->active_channels[CTCM_WRITE] > 0) &&
995			(fsm_getstate(grp->fsm) < MPCG_STATE_XID2INITW)) {
996			fsm_newstate(grp->fsm, MPCG_STATE_XID2INITW);
997			CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
998				"%s: %s: MPC GROUP CHANNELS ACTIVE\n",
999						__func__, dev->name);
1000		}
1001	} else if ((action == MPC_CHANNEL_REMOVE) &&
1002			(ch->in_mpcgroup == 1)) {
1003		ch->in_mpcgroup = 0;
1004		grp->num_channel_paths--;
1005		grp->active_channels[direction]--;
1006
1007		if (ch->xid_skb != NULL)
1008			dev_kfree_skb_any(ch->xid_skb);
1009		ch->xid_skb = NULL;
1010
1011		if (grp->channels_terminating)
1012					goto done;
1013
1014		if (((grp->active_channels[CTCM_READ] == 0) &&
1015					(grp->active_channels[CTCM_WRITE] > 0))
1016			|| ((grp->active_channels[CTCM_WRITE] == 0) &&
1017					(grp->active_channels[CTCM_READ] > 0)))
1018			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1019	}
1020done:
1021	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
1022		"exit %s: %i / Grp:%s total_channels=%i, active_channels: "
1023		"read=%i, write=%i\n", __func__, action,
1024		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
1025		grp->active_channels[CTCM_READ],
1026		grp->active_channels[CTCM_WRITE]);
1027
1028	CTCM_PR_DEBUG("exit %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
1029}
1030
1031/**
1032 * Unpack a just received skb and hand it over to
1033 * upper layers.
1034 * special MPC version of unpack_skb.
1035 *
1036 * ch		The channel where this skb has been received.
1037 * pskb		The received skb.
1038 */
1039static void ctcmpc_unpack_skb(struct channel *ch, struct sk_buff *pskb)
1040{
1041	struct net_device *dev	= ch->netdev;
1042	struct ctcm_priv *priv = dev->ml_priv;
1043	struct mpc_group *grp = priv->mpcg;
1044	struct pdu *curr_pdu;
1045	struct mpcg_info *mpcginfo;
1046	struct th_header *header = NULL;
1047	struct th_sweep *sweep = NULL;
1048	int pdu_last_seen = 0;
1049	__u32 new_len;
1050	struct sk_buff *skb;
1051	int skblen;
1052	int sendrc = 0;
1053
1054	CTCM_PR_DEBUG("ctcmpc enter: %s() %s cp:%i ch:%s\n",
1055			__func__, dev->name, smp_processor_id(), ch->id);
1056
1057	header = (struct th_header *)pskb->data;
1058	if ((header->th_seg == 0) &&
1059		(header->th_ch_flag == 0) &&
1060		(header->th_blk_flag == 0) &&
1061		(header->th_seq_num == 0))
1062		/* nothing for us */	goto done;
1063
1064	CTCM_PR_DBGDATA("%s: th_header\n", __func__);
1065	CTCM_D3_DUMP((char *)header, TH_HEADER_LENGTH);
1066	CTCM_PR_DBGDATA("%s: pskb len: %04x \n", __func__, pskb->len);
1067
1068	pskb->dev = dev;
1069	pskb->ip_summed = CHECKSUM_UNNECESSARY;
1070	skb_pull(pskb, TH_HEADER_LENGTH);
1071
1072	if (likely(header->th_ch_flag == TH_HAS_PDU)) {
1073		CTCM_PR_DBGDATA("%s: came into th_has_pdu\n", __func__);
1074		if ((fsm_getstate(grp->fsm) == MPCG_STATE_FLOWC) ||
1075		   ((fsm_getstate(grp->fsm) == MPCG_STATE_READY) &&
1076		    (header->th_seq_num != ch->th_seq_num + 1) &&
1077		    (ch->th_seq_num != 0))) {
1078			/* This is NOT the next segment		*
1079			 * we are not the correct race winner	*
1080			 * go away and let someone else win	*
1081			 * BUT..this only applies if xid negot	*
1082			 * is done				*
1083			*/
1084			grp->out_of_sequence += 1;
1085			__skb_push(pskb, TH_HEADER_LENGTH);
1086			skb_queue_tail(&ch->io_queue, pskb);
1087			CTCM_PR_DBGDATA("%s: th_seq_num expect:%08x "
1088					"got:%08x\n", __func__,
1089				ch->th_seq_num + 1, header->th_seq_num);
1090
1091			return;
1092		}
1093		grp->out_of_sequence = 0;
1094		ch->th_seq_num = header->th_seq_num;
1095
1096		CTCM_PR_DBGDATA("ctcmpc: %s() FromVTAM_th_seq=%08x\n",
1097					__func__, ch->th_seq_num);
1098
1099		if (unlikely(fsm_getstate(grp->fsm) != MPCG_STATE_READY))
1100					goto done;
1101		while ((pskb->len > 0) && !pdu_last_seen) {
1102			curr_pdu = (struct pdu *)pskb->data;
1103
1104			CTCM_PR_DBGDATA("%s: pdu_header\n", __func__);
1105			CTCM_D3_DUMP((char *)pskb->data, PDU_HEADER_LENGTH);
1106			CTCM_PR_DBGDATA("%s: pskb len: %04x \n",
1107						__func__, pskb->len);
1108
1109			skb_pull(pskb, PDU_HEADER_LENGTH);
1110
1111			if (curr_pdu->pdu_flag & PDU_LAST)
1112				pdu_last_seen = 1;
1113			if (curr_pdu->pdu_flag & PDU_CNTL)
1114				pskb->protocol = htons(ETH_P_SNAP);
1115			else
1116				pskb->protocol = htons(ETH_P_SNA_DIX);
1117
1118			if ((pskb->len <= 0) || (pskb->len > ch->max_bufsize)) {
1119				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1120					"%s(%s): Dropping packet with "
1121					"illegal siize %d",
1122					CTCM_FUNTAIL, dev->name, pskb->len);
1123
1124				priv->stats.rx_dropped++;
1125				priv->stats.rx_length_errors++;
1126					goto done;
1127			}
1128			skb_reset_mac_header(pskb);
1129			new_len = curr_pdu->pdu_offset;
1130			CTCM_PR_DBGDATA("%s: new_len: %04x \n",
1131						__func__, new_len);
1132			if ((new_len == 0) || (new_len > pskb->len)) {
1133				/* should never happen		    */
1134				/* pskb len must be hosed...bail out */
1135				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1136					"%s(%s): non valid pdu_offset: %04x",
1137					/* "data may be lost", */
1138					CTCM_FUNTAIL, dev->name, new_len);
1139				goto done;
1140			}
1141			skb = __dev_alloc_skb(new_len+4, GFP_ATOMIC);
1142
1143			if (!skb) {
1144				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1145					"%s(%s): MEMORY allocation error",
1146						CTCM_FUNTAIL, dev->name);
1147				priv->stats.rx_dropped++;
1148				fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1149						goto done;
1150			}
1151			skb_put_data(skb, pskb->data, new_len);
1152
1153			skb_reset_mac_header(skb);
1154			skb->dev = pskb->dev;
1155			skb->protocol = pskb->protocol;
1156			skb->ip_summed = CHECKSUM_UNNECESSARY;
1157			*((__u32 *) skb_push(skb, 4)) = ch->pdu_seq;
1158			ch->pdu_seq++;
1159
1160			if (do_debug_data) {
1161				ctcm_pr_debug("%s: ToDCM_pdu_seq= %08x\n",
1162						__func__, ch->pdu_seq);
1163				ctcm_pr_debug("%s: skb:%0lx "
1164					"skb len: %d \n", __func__,
1165					(unsigned long)skb, skb->len);
1166				ctcm_pr_debug("%s: up to 32 bytes "
1167					"of pdu_data sent\n", __func__);
1168				ctcmpc_dump32((char *)skb->data, skb->len);
1169			}
1170
1171			skblen = skb->len;
1172			sendrc = netif_rx(skb);
1173			priv->stats.rx_packets++;
1174			priv->stats.rx_bytes += skblen;
1175			skb_pull(pskb, new_len); /* point to next PDU */
1176		}
1177	} else {
1178		mpcginfo = kmalloc(sizeof(struct mpcg_info), gfp_type());
1179		if (mpcginfo == NULL)
1180					goto done;
1181
1182		mpcginfo->ch = ch;
1183		mpcginfo->th = header;
1184		mpcginfo->skb = pskb;
1185		CTCM_PR_DEBUG("%s: Not PDU - may be control pkt\n",
1186					__func__);
1187		/*  it's a sweep?   */
1188		sweep = (struct th_sweep *)pskb->data;
1189		mpcginfo->sweep = sweep;
1190		if (header->th_ch_flag == TH_SWEEP_REQ)
1191			mpc_rcvd_sweep_req(mpcginfo);
1192		else if (header->th_ch_flag == TH_SWEEP_RESP)
1193			mpc_rcvd_sweep_resp(mpcginfo);
1194		else if (header->th_blk_flag == TH_DATA_IS_XID) {
1195			struct xid2 *thisxid = (struct xid2 *)pskb->data;
1196			skb_pull(pskb, XID2_LENGTH);
1197			mpcginfo->xid = thisxid;
1198			fsm_event(grp->fsm, MPCG_EVENT_XID2, mpcginfo);
1199		} else if (header->th_blk_flag == TH_DISCONTACT)
1200			fsm_event(grp->fsm, MPCG_EVENT_DISCONC, mpcginfo);
1201		else if (header->th_seq_num != 0) {
1202			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1203				"%s(%s): control pkt expected\n",
1204						CTCM_FUNTAIL, dev->name);
1205			priv->stats.rx_dropped++;
1206			/* mpcginfo only used for non-data transfers */
1207			if (do_debug_data)
1208				ctcmpc_dump_skb(pskb, -8);
1209		}
1210		kfree(mpcginfo);
1211	}
1212done:
1213
1214	dev_kfree_skb_any(pskb);
1215	if (sendrc == NET_RX_DROP) {
1216		dev_warn(&dev->dev,
1217			"The network backlog for %s is exceeded, "
1218			"package dropped\n", __func__);
1219		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1220	}
1221
1222	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
1223			__func__, dev->name, ch, ch->id);
1224}
1225
1226/**
1227 * tasklet helper for mpc's skb unpacking.
1228 *
1229 * ch		The channel to work on.
1230 * Allow flow control back pressure to occur here.
1231 * Throttling back channel can result in excessive
1232 * channel inactivity and system deact of channel
1233 */
1234void ctcmpc_bh(unsigned long thischan)
1235{
1236	struct channel	  *ch	= (struct channel *)thischan;
1237	struct sk_buff	  *skb;
1238	struct net_device *dev	= ch->netdev;
1239	struct ctcm_priv  *priv	= dev->ml_priv;
1240	struct mpc_group  *grp	= priv->mpcg;
1241
1242	CTCM_PR_DEBUG("%s cp:%i enter:  %s() %s\n",
1243	       dev->name, smp_processor_id(), __func__, ch->id);
1244	/* caller has requested driver to throttle back */
1245	while ((fsm_getstate(grp->fsm) != MPCG_STATE_FLOWC) &&
1246			(skb = skb_dequeue(&ch->io_queue))) {
1247		ctcmpc_unpack_skb(ch, skb);
1248		if (grp->out_of_sequence > 20) {
1249			/* assume data loss has occurred if */
1250			/* missing seq_num for extended     */
1251			/* period of time		    */
1252			grp->out_of_sequence = 0;
1253			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1254			break;
1255		}
1256		if (skb == skb_peek(&ch->io_queue))
1257			break;
1258	}
1259	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
1260			__func__, dev->name, ch, ch->id);
1261	return;
1262}
1263
1264/*
1265 *  MPC Group Initializations
1266 */
1267struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv)
1268{
1269	struct mpc_group *grp;
1270
1271	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
1272			"Enter %s(%p)", CTCM_FUNTAIL, priv);
1273
1274	grp = kzalloc(sizeof(struct mpc_group), GFP_KERNEL);
1275	if (grp == NULL)
1276		return NULL;
1277
1278	grp->fsm = init_fsm("mpcg", mpcg_state_names, mpcg_event_names,
1279			MPCG_NR_STATES, MPCG_NR_EVENTS, mpcg_fsm,
1280			mpcg_fsm_len, GFP_KERNEL);
1281	if (grp->fsm == NULL) {
1282		kfree(grp);
1283		return NULL;
1284	}
1285
1286	fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1287	fsm_settimer(grp->fsm, &grp->timer);
1288
1289	grp->xid_skb =
1290		 __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
1291	if (grp->xid_skb == NULL) {
1292		kfree_fsm(grp->fsm);
1293		kfree(grp);
1294		return NULL;
1295	}
1296	/*  base xid for all channels in group  */
1297	grp->xid_skb_data = grp->xid_skb->data;
1298	grp->xid_th = (struct th_header *)grp->xid_skb->data;
1299	skb_put_data(grp->xid_skb, &thnorm, TH_HEADER_LENGTH);
1300
1301	grp->xid = (struct xid2 *)skb_tail_pointer(grp->xid_skb);
1302	skb_put_data(grp->xid_skb, &init_xid, XID2_LENGTH);
1303	grp->xid->xid2_adj_id = jiffies | 0xfff00000;
1304	grp->xid->xid2_sender_id = jiffies;
1305
1306	grp->xid_id = skb_tail_pointer(grp->xid_skb);
1307	skb_put_data(grp->xid_skb, "VTAM", 4);
1308
1309	grp->rcvd_xid_skb =
1310		__dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
1311	if (grp->rcvd_xid_skb == NULL) {
1312		kfree_fsm(grp->fsm);
1313		dev_kfree_skb(grp->xid_skb);
1314		kfree(grp);
1315		return NULL;
1316	}
1317	grp->rcvd_xid_data = grp->rcvd_xid_skb->data;
1318	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
1319	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
1320	grp->saved_xid2 = NULL;
1321	priv->xid = grp->xid;
1322	priv->mpcg = grp;
1323	return grp;
1324}
1325
1326/*
1327 * The MPC Group Station FSM
1328 */
1329
1330/*
1331 * MPC Group Station FSM actions
1332 * CTCM_PROTO_MPC only
1333 */
1334
1335/**
1336 * NOP action for statemachines
1337 */
1338static void mpc_action_nop(fsm_instance *fi, int event, void *arg)
1339{
1340}
1341
1342/*
1343 * invoked when the device transitions to dev_stopped
1344 * MPC will stop each individual channel if a single XID failure
1345 * occurs, or will intitiate all channels be stopped if a GROUP
1346 * level failure occurs.
1347 */
1348static void mpc_action_go_inop(fsm_instance *fi, int event, void *arg)
1349{
1350	struct net_device  *dev = arg;
1351	struct ctcm_priv    *priv;
1352	struct mpc_group *grp;
1353	struct channel *wch;
1354
1355	CTCM_PR_DEBUG("Enter %s: %s\n",	__func__, dev->name);
1356
1357	priv  = dev->ml_priv;
1358	grp =  priv->mpcg;
1359	grp->flow_off_called = 0;
1360	fsm_deltimer(&grp->timer);
1361	if (grp->channels_terminating)
1362			return;
1363
1364	grp->channels_terminating = 1;
1365	grp->saved_state = fsm_getstate(grp->fsm);
1366	fsm_newstate(grp->fsm, MPCG_STATE_INOP);
1367	if (grp->saved_state > MPCG_STATE_XID7INITF)
1368		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1369			"%s(%s): MPC GROUP INOPERATIVE",
1370				CTCM_FUNTAIL, dev->name);
1371	if ((grp->saved_state != MPCG_STATE_RESET) ||
1372		/* dealloc_channel has been called */
1373		(grp->port_persist == 0))
1374		fsm_deltimer(&priv->restart_timer);
1375
1376	wch = priv->channel[CTCM_WRITE];
1377
1378	switch (grp->saved_state) {
1379	case MPCG_STATE_RESET:
1380	case MPCG_STATE_INOP:
1381	case MPCG_STATE_XID2INITW:
1382	case MPCG_STATE_XID0IOWAIT:
1383	case MPCG_STATE_XID2INITX:
1384	case MPCG_STATE_XID7INITW:
1385	case MPCG_STATE_XID7INITX:
1386	case MPCG_STATE_XID0IOWAIX:
1387	case MPCG_STATE_XID7INITI:
1388	case MPCG_STATE_XID7INITZ:
1389	case MPCG_STATE_XID7INITF:
1390		break;
1391	case MPCG_STATE_FLOWC:
1392	case MPCG_STATE_READY:
1393	default:
1394		tasklet_hi_schedule(&wch->ch_disc_tasklet);
1395	}
1396
1397	grp->xid2_tgnum = 0;
1398	grp->group_max_buflen = 0;  /*min of all received */
1399	grp->outstanding_xid2 = 0;
1400	grp->outstanding_xid7 = 0;
1401	grp->outstanding_xid7_p2 = 0;
1402	grp->saved_xid2 = NULL;
1403	grp->xidnogood = 0;
1404	grp->changed_side = 0;
1405
1406	grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
1407	skb_reset_tail_pointer(grp->rcvd_xid_skb);
1408	grp->rcvd_xid_skb->len = 0;
1409	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
1410	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
1411
1412	if (grp->send_qllc_disc == 1) {
1413		grp->send_qllc_disc = 0;
1414		mpc_send_qllc_discontact(dev);
1415	}
1416
1417	/* DO NOT issue DEV_EVENT_STOP directly out of this code */
1418	/* This can result in INOP of VTAM PU due to halting of  */
1419	/* outstanding IO which causes a sense to be returned	 */
1420	/* Only about 3 senses are allowed and then IOS/VTAM will*/
1421	/* become unreachable without manual intervention	 */
1422	if ((grp->port_persist == 1) || (grp->alloc_called)) {
1423		grp->alloc_called = 0;
1424		fsm_deltimer(&priv->restart_timer);
1425		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_RESTART, dev);
1426		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1427		if (grp->saved_state > MPCG_STATE_XID7INITF)
1428			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
1429				"%s(%s): MPC GROUP RECOVERY SCHEDULED",
1430					CTCM_FUNTAIL, dev->name);
1431	} else {
1432		fsm_deltimer(&priv->restart_timer);
1433		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_STOP, dev);
1434		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
1435		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
1436			"%s(%s): NO MPC GROUP RECOVERY ATTEMPTED",
1437						CTCM_FUNTAIL, dev->name);
1438	}
1439}
1440
1441/**
1442 * Handle mpc group  action timeout.
1443 * MPC Group Station FSM action
1444 * CTCM_PROTO_MPC only
1445 *
1446 * fi		An instance of an mpc_group fsm.
1447 * event	The event, just happened.
1448 * arg		Generic pointer, casted from net_device * upon call.
1449 */
1450static void mpc_action_timeout(fsm_instance *fi, int event, void *arg)
1451{
1452	struct net_device *dev = arg;
1453	struct ctcm_priv *priv;
1454	struct mpc_group *grp;
1455	struct channel *wch;
1456	struct channel *rch;
1457
1458	priv = dev->ml_priv;
1459	grp = priv->mpcg;
1460	wch = priv->channel[CTCM_WRITE];
1461	rch = priv->channel[CTCM_READ];
1462
1463	switch (fsm_getstate(grp->fsm)) {
1464	case MPCG_STATE_XID2INITW:
1465		/* Unless there is outstanding IO on the  */
1466		/* channel just return and wait for ATTN  */
1467		/* interrupt to begin XID negotiations	  */
1468		if ((fsm_getstate(rch->fsm) == CH_XID0_PENDING) &&
1469		   (fsm_getstate(wch->fsm) == CH_XID0_PENDING))
1470			break;
1471		fallthrough;
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 */
1486void 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 */
1517void 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], 0, 0xff, 0);
1525	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1526
1527	if (rc != 0) {
1528		ctcm_ccw_check_rc(ch, rc, (char *)__func__);
1529	}
1530
1531	return;
1532}
1533
1534
1535/*
1536 * helper function of mpc FSM
1537 * CTCM_PROTO_MPC only
1538 * mpc_action_rcvd_xid7
1539*/
1540static int mpc_validate_xid(struct mpcg_info *mpcginfo)
1541{
1542	struct channel	   *ch	 = mpcginfo->ch;
1543	struct net_device  *dev  = ch->netdev;
1544	struct ctcm_priv   *priv = dev->ml_priv;
1545	struct mpc_group   *grp  = priv->mpcg;
1546	struct xid2	   *xid  = mpcginfo->xid;
1547	int	rc	 = 0;
1548	__u64	our_id   = 0;
1549	__u64   their_id = 0;
1550	int	len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1551
1552	CTCM_PR_DEBUG("Enter %s: xid=%p\n", __func__, xid);
1553
1554	if (xid == NULL) {
1555		rc = 1;
1556		/* XID REJECTED: xid == NULL */
1557		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1558			"%s(%s): xid = NULL",
1559				CTCM_FUNTAIL, ch->id);
1560			goto done;
1561	}
1562
1563	CTCM_D3_DUMP((char *)xid, XID2_LENGTH);
1564
1565	/*the received direction should be the opposite of ours  */
1566	if (((CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ? XID2_WRITE_SIDE :
1567				XID2_READ_SIDE) != xid->xid2_dlc_type) {
1568		rc = 2;
1569		/* XID REJECTED: r/w channel pairing mismatch */
1570		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1571			"%s(%s): r/w channel pairing mismatch",
1572				CTCM_FUNTAIL, ch->id);
1573			goto done;
1574	}
1575
1576	if (xid->xid2_dlc_type == XID2_READ_SIDE) {
1577		CTCM_PR_DEBUG("%s: grpmaxbuf:%d xid2buflen:%d\n", __func__,
1578				grp->group_max_buflen, xid->xid2_buf_len);
1579
1580		if (grp->group_max_buflen == 0 || grp->group_max_buflen >
1581						xid->xid2_buf_len - len)
1582			grp->group_max_buflen = xid->xid2_buf_len - len;
1583	}
1584
1585	if (grp->saved_xid2 == NULL) {
1586		grp->saved_xid2 =
1587			(struct xid2 *)skb_tail_pointer(grp->rcvd_xid_skb);
1588
1589		skb_put_data(grp->rcvd_xid_skb, xid, XID2_LENGTH);
1590		grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
1591
1592		skb_reset_tail_pointer(grp->rcvd_xid_skb);
1593		grp->rcvd_xid_skb->len = 0;
1594
1595		/* convert two 32 bit numbers into 1 64 bit for id compare */
1596		our_id = (__u64)priv->xid->xid2_adj_id;
1597		our_id = our_id << 32;
1598		our_id = our_id + priv->xid->xid2_sender_id;
1599		their_id = (__u64)xid->xid2_adj_id;
1600		their_id = their_id << 32;
1601		their_id = their_id + xid->xid2_sender_id;
1602		/* lower id assume the xside role */
1603		if (our_id < their_id) {
1604			grp->roll = XSIDE;
1605			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1606				"%s(%s): WE HAVE LOW ID - TAKE XSIDE",
1607					CTCM_FUNTAIL, ch->id);
1608		} else {
1609			grp->roll = YSIDE;
1610			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
1611				"%s(%s): WE HAVE HIGH ID - TAKE YSIDE",
1612					CTCM_FUNTAIL, ch->id);
1613		}
1614
1615	} else {
1616		if (xid->xid2_flag4 != grp->saved_xid2->xid2_flag4) {
1617			rc = 3;
1618			/* XID REJECTED: xid flag byte4 mismatch */
1619			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1620				"%s(%s): xid flag byte4 mismatch",
1621					CTCM_FUNTAIL, ch->id);
1622		}
1623		if (xid->xid2_flag2 == 0x40) {
1624			rc = 4;
1625			/* XID REJECTED - xid NOGOOD */
1626			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1627				"%s(%s): xid NOGOOD",
1628					CTCM_FUNTAIL, ch->id);
1629		}
1630		if (xid->xid2_adj_id != grp->saved_xid2->xid2_adj_id) {
1631			rc = 5;
1632			/* XID REJECTED - Adjacent Station ID Mismatch */
1633			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1634				"%s(%s): Adjacent Station ID Mismatch",
1635					CTCM_FUNTAIL, ch->id);
1636		}
1637		if (xid->xid2_sender_id != grp->saved_xid2->xid2_sender_id) {
1638			rc = 6;
1639			/* XID REJECTED - Sender Address Mismatch */
1640			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1641				"%s(%s): Sender Address Mismatch",
1642					CTCM_FUNTAIL, ch->id);
1643		}
1644	}
1645done:
1646	if (rc) {
1647		dev_warn(&dev->dev,
1648			"The XID used in the MPC protocol is not valid, "
1649			"rc = %d\n", rc);
1650		priv->xid->xid2_flag2 = 0x40;
1651		grp->saved_xid2->xid2_flag2 = 0x40;
1652	}
1653
1654	return rc;
1655}
1656
1657/*
1658 * MPC Group Station FSM action
1659 * CTCM_PROTO_MPC only
1660 */
1661static void mpc_action_side_xid(fsm_instance *fsm, void *arg, int side)
1662{
1663	struct channel *ch = arg;
1664	int rc = 0;
1665	int gotlock = 0;
1666	unsigned long saveflags = 0;	/* avoids compiler warning with
1667					   spin_unlock_irqrestore */
1668
1669	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
1670			__func__, smp_processor_id(), ch, ch->id);
1671
1672	if (ctcm_checkalloc_buffer(ch))
1673					goto done;
1674
1675	/*
1676	 * skb data-buffer referencing:
1677	 */
1678	ch->trans_skb->data = ch->trans_skb_data;
1679	skb_reset_tail_pointer(ch->trans_skb);
1680	ch->trans_skb->len = 0;
1681	/* result of the previous 3 statements is NOT always
1682	 * already set after ctcm_checkalloc_buffer
1683	 * because of possible reuse of the trans_skb
1684	 */
1685	memset(ch->trans_skb->data, 0, 16);
1686	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
1687	/* check is main purpose here: */
1688	skb_put(ch->trans_skb, TH_HEADER_LENGTH);
1689	ch->rcvd_xid = (struct xid2 *)skb_tail_pointer(ch->trans_skb);
1690	/* check is main purpose here: */
1691	skb_put(ch->trans_skb, XID2_LENGTH);
1692	ch->rcvd_xid_id = skb_tail_pointer(ch->trans_skb);
1693	/* cleanup back to startpoint */
1694	ch->trans_skb->data = ch->trans_skb_data;
1695	skb_reset_tail_pointer(ch->trans_skb);
1696	ch->trans_skb->len = 0;
1697
1698	/* non-checking rewrite of above skb data-buffer referencing: */
1699	/*
1700	memset(ch->trans_skb->data, 0, 16);
1701	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
1702	ch->rcvd_xid = (struct xid2 *)(ch->trans_skb_data + TH_HEADER_LENGTH);
1703	ch->rcvd_xid_id = ch->trans_skb_data + TH_HEADER_LENGTH + XID2_LENGTH;
1704	 */
1705
1706	ch->ccw[8].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1707	ch->ccw[8].count	= 0;
1708	ch->ccw[8].cda		= 0x00;
1709
1710	if (!(ch->xid_th && ch->xid && ch->xid_id))
1711		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_INFO,
1712			"%s(%s): xid_th=%p, xid=%p, xid_id=%p",
1713			CTCM_FUNTAIL, ch->id, ch->xid_th, ch->xid, ch->xid_id);
1714
1715	if (side == XSIDE) {
1716		/* mpc_action_xside_xid */
1717		if (ch->xid_th == NULL)
1718				goto done;
1719		ch->ccw[9].cmd_code	= CCW_CMD_WRITE;
1720		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1721		ch->ccw[9].count	= TH_HEADER_LENGTH;
1722		ch->ccw[9].cda		= virt_to_phys(ch->xid_th);
1723
1724		if (ch->xid == NULL)
1725				goto done;
1726		ch->ccw[10].cmd_code	= CCW_CMD_WRITE;
1727		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1728		ch->ccw[10].count	= XID2_LENGTH;
1729		ch->ccw[10].cda		= virt_to_phys(ch->xid);
1730
1731		ch->ccw[11].cmd_code	= CCW_CMD_READ;
1732		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1733		ch->ccw[11].count	= TH_HEADER_LENGTH;
1734		ch->ccw[11].cda		= virt_to_phys(ch->rcvd_xid_th);
1735
1736		ch->ccw[12].cmd_code	= CCW_CMD_READ;
1737		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1738		ch->ccw[12].count	= XID2_LENGTH;
1739		ch->ccw[12].cda		= virt_to_phys(ch->rcvd_xid);
1740
1741		ch->ccw[13].cmd_code	= CCW_CMD_READ;
1742		ch->ccw[13].cda		= virt_to_phys(ch->rcvd_xid_id);
1743
1744	} else { /* side == YSIDE : mpc_action_yside_xid */
1745		ch->ccw[9].cmd_code	= CCW_CMD_READ;
1746		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1747		ch->ccw[9].count	= TH_HEADER_LENGTH;
1748		ch->ccw[9].cda		= virt_to_phys(ch->rcvd_xid_th);
1749
1750		ch->ccw[10].cmd_code	= CCW_CMD_READ;
1751		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1752		ch->ccw[10].count	= XID2_LENGTH;
1753		ch->ccw[10].cda		= virt_to_phys(ch->rcvd_xid);
1754
1755		if (ch->xid_th == NULL)
1756				goto done;
1757		ch->ccw[11].cmd_code	= CCW_CMD_WRITE;
1758		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1759		ch->ccw[11].count	= TH_HEADER_LENGTH;
1760		ch->ccw[11].cda		= virt_to_phys(ch->xid_th);
1761
1762		if (ch->xid == NULL)
1763				goto done;
1764		ch->ccw[12].cmd_code	= CCW_CMD_WRITE;
1765		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1766		ch->ccw[12].count	= XID2_LENGTH;
1767		ch->ccw[12].cda		= virt_to_phys(ch->xid);
1768
1769		if (ch->xid_id == NULL)
1770				goto done;
1771		ch->ccw[13].cmd_code	= CCW_CMD_WRITE;
1772		ch->ccw[13].cda		= virt_to_phys(ch->xid_id);
1773
1774	}
1775	ch->ccw[13].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
1776	ch->ccw[13].count	= 4;
1777
1778	ch->ccw[14].cmd_code	= CCW_CMD_NOOP;
1779	ch->ccw[14].flags	= CCW_FLAG_SLI;
1780	ch->ccw[14].count	= 0;
1781	ch->ccw[14].cda		= 0;
1782
1783	CTCM_CCW_DUMP((char *)&ch->ccw[8], sizeof(struct ccw1) * 7);
1784	CTCM_D3_DUMP((char *)ch->xid_th, TH_HEADER_LENGTH);
1785	CTCM_D3_DUMP((char *)ch->xid, XID2_LENGTH);
1786	CTCM_D3_DUMP((char *)ch->xid_id, 4);
1787
1788	if (!in_irq()) {
1789			 /* Such conditional locking is a known problem for
1790			  * sparse because its static undeterministic.
1791			  * Warnings should be ignored here. */
1792		spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
1793		gotlock = 1;
1794	}
1795
1796	fsm_addtimer(&ch->timer, 5000 , CTC_EVENT_TIMER, ch);
1797	rc = ccw_device_start(ch->cdev, &ch->ccw[8], 0, 0xff, 0);
1798
1799	if (gotlock)	/* see remark above about conditional locking */
1800		spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
1801
1802	if (rc != 0) {
1803		ctcm_ccw_check_rc(ch, rc,
1804				(side == XSIDE) ? "x-side XID" : "y-side XID");
1805	}
1806
1807done:
1808	CTCM_PR_DEBUG("Exit %s: ch=0x%p id=%s\n",
1809				__func__, ch, ch->id);
1810	return;
1811
1812}
1813
1814/*
1815 * MPC Group Station FSM action
1816 * CTCM_PROTO_MPC only
1817 */
1818static void mpc_action_xside_xid(fsm_instance *fsm, int event, void *arg)
1819{
1820	mpc_action_side_xid(fsm, arg, XSIDE);
1821}
1822
1823/*
1824 * MPC Group Station FSM action
1825 * CTCM_PROTO_MPC only
1826 */
1827static void mpc_action_yside_xid(fsm_instance *fsm, int event, void *arg)
1828{
1829	mpc_action_side_xid(fsm, arg, YSIDE);
1830}
1831
1832/*
1833 * MPC Group Station FSM action
1834 * CTCM_PROTO_MPC only
1835 */
1836static void mpc_action_doxid0(fsm_instance *fsm, int event, void *arg)
1837{
1838	struct channel	   *ch   = arg;
1839	struct net_device  *dev  = ch->netdev;
1840	struct ctcm_priv   *priv = dev->ml_priv;
1841	struct mpc_group   *grp  = priv->mpcg;
1842
1843	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
1844			__func__, smp_processor_id(), ch, ch->id);
1845
1846	if (ch->xid == NULL) {
1847		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1848			"%s(%s): ch->xid == NULL",
1849				CTCM_FUNTAIL, dev->name);
1850		return;
1851	}
1852
1853	fsm_newstate(ch->fsm, CH_XID0_INPROGRESS);
1854
1855	ch->xid->xid2_option =	XID2_0;
1856
1857	switch (fsm_getstate(grp->fsm)) {
1858	case MPCG_STATE_XID2INITW:
1859	case MPCG_STATE_XID2INITX:
1860		ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1861		break;
1862	case MPCG_STATE_XID0IOWAIT:
1863	case MPCG_STATE_XID0IOWAIX:
1864		ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1865		break;
1866	}
1867
1868	fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
1869
1870	return;
1871}
1872
1873/*
1874 * MPC Group Station FSM action
1875 * CTCM_PROTO_MPC only
1876*/
1877static void mpc_action_doxid7(fsm_instance *fsm, int event, void *arg)
1878{
1879	struct net_device *dev = arg;
1880	struct ctcm_priv  *priv = dev->ml_priv;
1881	struct mpc_group  *grp  = NULL;
1882	int direction;
1883	int send = 0;
1884
1885	if (priv)
1886		grp = priv->mpcg;
1887	if (grp == NULL)
1888		return;
1889
1890	for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1891		struct channel *ch = priv->channel[direction];
1892		struct xid2 *thisxid = ch->xid;
1893		ch->xid_skb->data = ch->xid_skb_data;
1894		skb_reset_tail_pointer(ch->xid_skb);
1895		ch->xid_skb->len = 0;
1896		thisxid->xid2_option = XID2_7;
1897		send = 0;
1898
1899		/* xid7 phase 1 */
1900		if (grp->outstanding_xid7_p2 > 0) {
1901			if (grp->roll == YSIDE) {
1902				if (fsm_getstate(ch->fsm) == CH_XID7_PENDING1) {
1903					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
1904					ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1905					skb_put_data(ch->xid_skb, &thdummy,
1906						     TH_HEADER_LENGTH);
1907					send = 1;
1908				}
1909			} else if (fsm_getstate(ch->fsm) < CH_XID7_PENDING2) {
1910					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
1911					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1912					skb_put_data(ch->xid_skb, &thnorm,
1913						     TH_HEADER_LENGTH);
1914					send = 1;
1915			}
1916		} else {
1917			/* xid7 phase 2 */
1918			if (grp->roll == YSIDE) {
1919				if (fsm_getstate(ch->fsm) < CH_XID7_PENDING4) {
1920					fsm_newstate(ch->fsm, CH_XID7_PENDING4);
1921					skb_put_data(ch->xid_skb, &thnorm,
1922						     TH_HEADER_LENGTH);
1923					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
1924					send = 1;
1925				}
1926			} else if (fsm_getstate(ch->fsm) == CH_XID7_PENDING3) {
1927				fsm_newstate(ch->fsm, CH_XID7_PENDING4);
1928				ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
1929				skb_put_data(ch->xid_skb, &thdummy,
1930					     TH_HEADER_LENGTH);
1931				send = 1;
1932			}
1933		}
1934
1935		if (send)
1936			fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
1937	}
1938
1939	return;
1940}
1941
1942/*
1943 * MPC Group Station FSM action
1944 * CTCM_PROTO_MPC only
1945 */
1946static void mpc_action_rcvd_xid0(fsm_instance *fsm, int event, void *arg)
1947{
1948
1949	struct mpcg_info   *mpcginfo  = arg;
1950	struct channel	   *ch   = mpcginfo->ch;
1951	struct net_device  *dev  = ch->netdev;
1952	struct ctcm_priv   *priv = dev->ml_priv;
1953	struct mpc_group   *grp  = priv->mpcg;
1954
1955	CTCM_PR_DEBUG("%s: ch-id:%s xid2:%i xid7:%i xidt_p2:%i \n",
1956			__func__, ch->id, grp->outstanding_xid2,
1957			grp->outstanding_xid7, grp->outstanding_xid7_p2);
1958
1959	if (fsm_getstate(ch->fsm) < CH_XID7_PENDING)
1960		fsm_newstate(ch->fsm, CH_XID7_PENDING);
1961
1962	grp->outstanding_xid2--;
1963	grp->outstanding_xid7++;
1964	grp->outstanding_xid7_p2++;
1965
1966	/* must change state before validating xid to */
1967	/* properly handle interim interrupts received*/
1968	switch (fsm_getstate(grp->fsm)) {
1969	case MPCG_STATE_XID2INITW:
1970		fsm_newstate(grp->fsm, MPCG_STATE_XID2INITX);
1971		mpc_validate_xid(mpcginfo);
1972		break;
1973	case MPCG_STATE_XID0IOWAIT:
1974		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIX);
1975		mpc_validate_xid(mpcginfo);
1976		break;
1977	case MPCG_STATE_XID2INITX:
1978		if (grp->outstanding_xid2 == 0) {
1979			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITW);
1980			mpc_validate_xid(mpcginfo);
1981			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
1982		}
1983		break;
1984	case MPCG_STATE_XID0IOWAIX:
1985		if (grp->outstanding_xid2 == 0) {
1986			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITI);
1987			mpc_validate_xid(mpcginfo);
1988			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
1989		}
1990		break;
1991	}
1992
1993	CTCM_PR_DEBUG("ctcmpc:%s() %s xid2:%i xid7:%i xidt_p2:%i \n",
1994		__func__, ch->id, grp->outstanding_xid2,
1995		grp->outstanding_xid7, grp->outstanding_xid7_p2);
1996	CTCM_PR_DEBUG("ctcmpc:%s() %s grpstate: %s chanstate: %s \n",
1997		__func__, ch->id,
1998		fsm_getstate_str(grp->fsm), fsm_getstate_str(ch->fsm));
1999	return;
2000
2001}
2002
2003
2004/*
2005 * MPC Group Station FSM action
2006 * CTCM_PROTO_MPC only
2007 */
2008static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg)
2009{
2010	struct mpcg_info   *mpcginfo   = arg;
2011	struct channel	   *ch	       = mpcginfo->ch;
2012	struct net_device  *dev        = ch->netdev;
2013	struct ctcm_priv   *priv    = dev->ml_priv;
2014	struct mpc_group   *grp     = priv->mpcg;
2015
2016	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
2017		__func__, smp_processor_id(), ch, ch->id);
2018	CTCM_PR_DEBUG("%s: outstanding_xid7: %i, outstanding_xid7_p2: %i\n",
2019		__func__, grp->outstanding_xid7, grp->outstanding_xid7_p2);
2020
2021	grp->outstanding_xid7--;
2022	ch->xid_skb->data = ch->xid_skb_data;
2023	skb_reset_tail_pointer(ch->xid_skb);
2024	ch->xid_skb->len = 0;
2025
2026	switch (fsm_getstate(grp->fsm)) {
2027	case MPCG_STATE_XID7INITI:
2028		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITZ);
2029		mpc_validate_xid(mpcginfo);
2030		break;
2031	case MPCG_STATE_XID7INITW:
2032		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITX);
2033		mpc_validate_xid(mpcginfo);
2034		break;
2035	case MPCG_STATE_XID7INITZ:
2036	case MPCG_STATE_XID7INITX:
2037		if (grp->outstanding_xid7 == 0) {
2038			if (grp->outstanding_xid7_p2 > 0) {
2039				grp->outstanding_xid7 =
2040					grp->outstanding_xid7_p2;
2041				grp->outstanding_xid7_p2 = 0;
2042			} else
2043				fsm_newstate(grp->fsm, MPCG_STATE_XID7INITF);
2044
2045			mpc_validate_xid(mpcginfo);
2046			fsm_event(grp->fsm, MPCG_EVENT_XID7DONE, dev);
2047			break;
2048		}
2049		mpc_validate_xid(mpcginfo);
2050		break;
2051	}
2052	return;
2053}
2054
2055/*
2056 * mpc_action helper of an MPC Group Station FSM action
2057 * CTCM_PROTO_MPC only
2058 */
2059static int mpc_send_qllc_discontact(struct net_device *dev)
2060{
2061	__u32	new_len	= 0;
2062	struct sk_buff   *skb;
2063	struct qllc      *qllcptr;
2064	struct ctcm_priv *priv = dev->ml_priv;
2065	struct mpc_group *grp = priv->mpcg;
2066
2067	CTCM_PR_DEBUG("%s: GROUP STATE: %s\n",
2068		__func__, mpcg_state_names[grp->saved_state]);
2069
2070	switch (grp->saved_state) {
2071	/*
2072	 * establish conn callback function is
2073	 * preferred method to report failure
2074	 */
2075	case MPCG_STATE_XID0IOWAIT:
2076	case MPCG_STATE_XID0IOWAIX:
2077	case MPCG_STATE_XID7INITI:
2078	case MPCG_STATE_XID7INITZ:
2079	case MPCG_STATE_XID2INITW:
2080	case MPCG_STATE_XID2INITX:
2081	case MPCG_STATE_XID7INITW:
2082	case MPCG_STATE_XID7INITX:
2083		if (grp->estconnfunc) {
2084			grp->estconnfunc(grp->port_num, -1, 0);
2085			grp->estconnfunc = NULL;
2086			break;
2087		}
2088		fallthrough;
2089	case MPCG_STATE_FLOWC:
2090	case MPCG_STATE_READY:
2091		grp->send_qllc_disc = 2;
2092		new_len = sizeof(struct qllc);
2093		qllcptr = kzalloc(new_len, gfp_type() | GFP_DMA);
2094		if (qllcptr == NULL) {
2095			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2096				"%s(%s): qllcptr allocation error",
2097						CTCM_FUNTAIL, dev->name);
2098			return -ENOMEM;
2099		}
2100
2101		qllcptr->qllc_address = 0xcc;
2102		qllcptr->qllc_commands = 0x03;
2103
2104		skb = __dev_alloc_skb(new_len, GFP_ATOMIC);
2105
2106		if (skb == NULL) {
2107			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2108				"%s(%s): skb allocation error",
2109						CTCM_FUNTAIL, dev->name);
2110			priv->stats.rx_dropped++;
2111			kfree(qllcptr);
2112			return -ENOMEM;
2113		}
2114
2115		skb_put_data(skb, qllcptr, new_len);
2116		kfree(qllcptr);
2117
2118		if (skb_headroom(skb) < 4) {
2119			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
2120				"%s(%s): skb_headroom error",
2121						CTCM_FUNTAIL, dev->name);
2122			dev_kfree_skb_any(skb);
2123			return -ENOMEM;
2124		}
2125
2126		*((__u32 *)skb_push(skb, 4)) =
2127			priv->channel[CTCM_READ]->pdu_seq;
2128		priv->channel[CTCM_READ]->pdu_seq++;
2129		CTCM_PR_DBGDATA("ctcmpc: %s ToDCM_pdu_seq= %08x\n",
2130				__func__, priv->channel[CTCM_READ]->pdu_seq);
2131
2132		/* receipt of CC03 resets anticipated sequence number on
2133		      receiving side */
2134		priv->channel[CTCM_READ]->pdu_seq = 0x00;
2135		skb_reset_mac_header(skb);
2136		skb->dev = dev;
2137		skb->protocol = htons(ETH_P_SNAP);
2138		skb->ip_summed = CHECKSUM_UNNECESSARY;
2139
2140		CTCM_D3_DUMP(skb->data, (sizeof(struct qllc) + 4));
2141
2142		netif_rx(skb);
2143		break;
2144	default:
2145		break;
2146
2147	}
2148
2149	return 0;
2150}
2151/* --- This is the END my friend --- */
2152
2153