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