Adding upstream version 5.10.209.upstream/5.10.209

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2152 insertions, 0 deletions

diff --git a/drivers/s390/net/ctcm_mpc.c b/drivers/s390/net/ctcm_mpc.c
new file mode 100644
index 000000000..20a6097e1
--- /dev/null
+++ b/drivers/s390/net/ctcm_mpc.c
@@ -0,0 +1,2152 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *	Copyright IBM Corp. 2004, 2007
+ *	Authors:	Belinda Thompson (belindat@us.ibm.com)
+ *			Andy Richter (richtera@us.ibm.com)
+ *			Peter Tiedemann (ptiedem@de.ibm.com)
+ */
+
+/*
+	This module exports functions to be used by CCS:
+	EXPORT_SYMBOL(ctc_mpc_alloc_channel);
+	EXPORT_SYMBOL(ctc_mpc_establish_connectivity);
+	EXPORT_SYMBOL(ctc_mpc_dealloc_ch);
+	EXPORT_SYMBOL(ctc_mpc_flow_control);
+*/
+
+#undef DEBUG
+#undef DEBUGDATA
+#undef DEBUGCCW
+
+#define KMSG_COMPONENT "ctcm"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/types.h>
+#include <linux/interrupt.h>
+#include <linux/timer.h>
+#include <linux/sched.h>
+
+#include <linux/signal.h>
+#include <linux/string.h>
+#include <linux/proc_fs.h>
+
+#include <linux/ip.h>
+#include <linux/if_arp.h>
+#include <linux/tcp.h>
+#include <linux/skbuff.h>
+#include <linux/ctype.h>
+#include <linux/netdevice.h>
+#include <net/dst.h>
+
+#include <linux/io.h>		/* instead of <asm/io.h> ok ? */
+#include <asm/ccwdev.h>
+#include <asm/ccwgroup.h>
+#include <linux/bitops.h>	/* instead of <asm/bitops.h> ok ? */
+#include <linux/uaccess.h>	/* instead of <asm/uaccess.h> ok ? */
+#include <linux/wait.h>
+#include <linux/moduleparam.h>
+#include <asm/idals.h>
+
+#include "ctcm_main.h"
+#include "ctcm_mpc.h"
+#include "ctcm_fsms.h"
+
+static const struct xid2 init_xid = {
+	.xid2_type_id	=	XID_FM2,
+	.xid2_len	=	0x45,
+	.xid2_adj_id	=	0,
+	.xid2_rlen	=	0x31,
+	.xid2_resv1	=	0,
+	.xid2_flag1	=	0,
+	.xid2_fmtt	=	0,
+	.xid2_flag4	=	0x80,
+	.xid2_resv2	=	0,
+	.xid2_tgnum	=	0,
+	.xid2_sender_id	=	0,
+	.xid2_flag2	=	0,
+	.xid2_option	=	XID2_0,
+	.xid2_resv3	=	"\x00",
+	.xid2_resv4	=	0,
+	.xid2_dlc_type	=	XID2_READ_SIDE,
+	.xid2_resv5	=	0,
+	.xid2_mpc_flag	=	0,
+	.xid2_resv6	=	0,
+	.xid2_buf_len	=	(MPC_BUFSIZE_DEFAULT - 35),
+};
+
+static const struct th_header thnorm = {
+	.th_seg		=	0x00,
+	.th_ch_flag	=	TH_IS_XID,
+	.th_blk_flag	=	TH_DATA_IS_XID,
+	.th_is_xid	=	0x01,
+	.th_seq_num	=	0x00000000,
+};
+
+static const struct th_header thdummy = {
+	.th_seg		=	0x00,
+	.th_ch_flag	=	0x00,
+	.th_blk_flag	=	TH_DATA_IS_XID,
+	.th_is_xid	=	0x01,
+	.th_seq_num	=	0x00000000,
+};
+
+/*
+ * Definition of one MPC group
+ */
+
+/*
+ * Compatibility macros for busy handling
+ * of network devices.
+ */
+
+static void ctcmpc_unpack_skb(struct channel *ch, struct sk_buff *pskb);
+
+/*
+ * MPC Group state machine actions (static prototypes)
+ */
+static void mpc_action_nop(fsm_instance *fsm, int event, void *arg);
+static void mpc_action_go_ready(fsm_instance *fsm, int event, void *arg);
+static void mpc_action_go_inop(fsm_instance *fi, int event, void *arg);
+static void mpc_action_timeout(fsm_instance *fi, int event, void *arg);
+static int  mpc_validate_xid(struct mpcg_info *mpcginfo);
+static void mpc_action_yside_xid(fsm_instance *fsm, int event, void *arg);
+static void mpc_action_doxid0(fsm_instance *fsm, int event, void *arg);
+static void mpc_action_doxid7(fsm_instance *fsm, int event, void *arg);
+static void mpc_action_xside_xid(fsm_instance *fsm, int event, void *arg);
+static void mpc_action_rcvd_xid0(fsm_instance *fsm, int event, void *arg);
+static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg);
+
+#ifdef DEBUGDATA
+/*-------------------------------------------------------------------*
+* Dump buffer format						     *
+*								     *
+*--------------------------------------------------------------------*/
+void ctcmpc_dumpit(char *buf, int len)
+{
+	__u32	ct, sw, rm, dup;
+	char	*ptr, *rptr;
+	char	tbuf[82], tdup[82];
+	char	addr[22];
+	char	boff[12];
+	char	bhex[82], duphex[82];
+	char	basc[40];
+
+	sw  = 0;
+	rptr = ptr = buf;
+	rm  = 16;
+	duphex[0] = 0x00;
+	dup = 0;
+
+	for (ct = 0; ct < len; ct++, ptr++, rptr++) {
+		if (sw == 0) {
+			sprintf(addr, "%16.16llx", (__u64)rptr);
+
+			sprintf(boff, "%4.4X", (__u32)ct);
+			bhex[0] = '\0';
+			basc[0] = '\0';
+		}
+		if ((sw == 4) || (sw == 12))
+			strcat(bhex, " ");
+		if (sw == 8)
+			strcat(bhex, "	");
+
+		sprintf(tbuf, "%2.2llX", (__u64)*ptr);
+
+		tbuf[2] = '\0';
+		strcat(bhex, tbuf);
+		if ((0 != isprint(*ptr)) && (*ptr >= 0x20))
+			basc[sw] = *ptr;
+		else
+			basc[sw] = '.';
+
+		basc[sw+1] = '\0';
+		sw++;
+		rm--;
+		if (sw != 16)
+			continue;
+		if ((strcmp(duphex, bhex)) != 0) {
+			if (dup != 0) {
+				sprintf(tdup,
+					"Duplicate as above to %s", addr);
+				ctcm_pr_debug("		       --- %s ---\n",
+						tdup);
+			}
+			ctcm_pr_debug("   %s (+%s) : %s  [%s]\n",
+					addr, boff, bhex, basc);
+			dup = 0;
+			strcpy(duphex, bhex);
+		} else
+			dup++;
+
+		sw = 0;
+		rm = 16;
+	}  /* endfor */
+
+	if (sw != 0) {
+		for ( ; rm > 0; rm--, sw++) {
+			if ((sw == 4) || (sw == 12))
+				strcat(bhex, " ");
+			if (sw == 8)
+				strcat(bhex, "	");
+			strcat(bhex, "	");
+			strcat(basc, " ");
+		}
+		if (dup != 0) {
+			sprintf(tdup, "Duplicate as above to %s", addr);
+			ctcm_pr_debug("		       --- %s ---\n", tdup);
+		}
+		ctcm_pr_debug("   %s (+%s) : %s  [%s]\n",
+					addr, boff, bhex, basc);
+	} else {
+		if (dup >= 1) {
+			sprintf(tdup, "Duplicate as above to %s", addr);
+			ctcm_pr_debug("		       --- %s ---\n", tdup);
+		}
+		if (dup != 0) {
+			ctcm_pr_debug("   %s (+%s) : %s  [%s]\n",
+				addr, boff, bhex, basc);
+		}
+	}
+
+	return;
+
+}   /*	 end of ctcmpc_dumpit  */
+#endif
+
+#ifdef DEBUGDATA
+/*
+ * Dump header and first 16 bytes of an sk_buff for debugging purposes.
+ *
+ * skb		The sk_buff to dump.
+ * offset	Offset relative to skb-data, where to start the dump.
+ */
+void ctcmpc_dump_skb(struct sk_buff *skb, int offset)
+{
+	__u8 *p = skb->data;
+	struct th_header *header;
+	struct pdu *pheader;
+	int bl = skb->len;
+	int i;
+
+	if (p == NULL)
+		return;
+
+	p += offset;
+	header = (struct th_header *)p;
+
+	ctcm_pr_debug("dump:\n");
+	ctcm_pr_debug("skb len=%d \n", skb->len);
+	if (skb->len > 2) {
+		switch (header->th_ch_flag) {
+		case TH_HAS_PDU:
+			break;
+		case 0x00:
+		case TH_IS_XID:
+			if ((header->th_blk_flag == TH_DATA_IS_XID) &&
+			   (header->th_is_xid == 0x01))
+				goto dumpth;
+		case TH_SWEEP_REQ:
+				goto dumpth;
+		case TH_SWEEP_RESP:
+				goto dumpth;
+		default:
+			break;
+		}
+
+		pheader = (struct pdu *)p;
+		ctcm_pr_debug("pdu->offset: %d hex: %04x\n",
+			       pheader->pdu_offset, pheader->pdu_offset);
+		ctcm_pr_debug("pdu->flag  : %02x\n", pheader->pdu_flag);
+		ctcm_pr_debug("pdu->proto : %02x\n", pheader->pdu_proto);
+		ctcm_pr_debug("pdu->seq   : %02x\n", pheader->pdu_seq);
+					goto dumpdata;
+
+dumpth:
+		ctcm_pr_debug("th->seg     : %02x\n", header->th_seg);
+		ctcm_pr_debug("th->ch      : %02x\n", header->th_ch_flag);
+		ctcm_pr_debug("th->blk_flag: %02x\n", header->th_blk_flag);
+		ctcm_pr_debug("th->type    : %s\n",
+			       (header->th_is_xid) ? "DATA" : "XID");
+		ctcm_pr_debug("th->seqnum  : %04x\n", header->th_seq_num);
+
+	}
+dumpdata:
+	if (bl > 32)
+		bl = 32;
+	ctcm_pr_debug("data: ");
+	for (i = 0; i < bl; i++)
+		ctcm_pr_debug("%02x%s", *p++, (i % 16) ? " " : "\n");
+	ctcm_pr_debug("\n");
+}
+#endif
+
+static struct net_device *ctcmpc_get_dev(int port_num)
+{
+	char device[20];
+	struct net_device *dev;
+	struct ctcm_priv *priv;
+
+	sprintf(device, "%s%i", MPC_DEVICE_NAME, port_num);
+
+	dev = __dev_get_by_name(&init_net, device);
+
+	if (dev == NULL) {
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s: Device not found by name: %s",
+					CTCM_FUNTAIL, device);
+		return NULL;
+	}
+	priv = dev->ml_priv;
+	if (priv == NULL) {
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): dev->ml_priv is NULL",
+					CTCM_FUNTAIL, device);
+		return NULL;
+	}
+	if (priv->mpcg == NULL) {
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): priv->mpcg is NULL",
+					CTCM_FUNTAIL, device);
+		return NULL;
+	}
+	return dev;
+}
+
+/*
+ * ctc_mpc_alloc_channel
+ *	(exported interface)
+ *
+ * Device Initialization :
+ *	ACTPATH  driven IO operations
+ */
+int ctc_mpc_alloc_channel(int port_num, void (*callback)(int, int))
+{
+	struct net_device *dev;
+	struct mpc_group *grp;
+	struct ctcm_priv *priv;
+
+	dev = ctcmpc_get_dev(port_num);
+	if (dev == NULL)
+		return 1;
+	priv = dev->ml_priv;
+	grp = priv->mpcg;
+
+	grp->allochanfunc = callback;
+	grp->port_num = port_num;
+	grp->port_persist = 1;
+
+	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
+			"%s(%s): state=%s",
+			CTCM_FUNTAIL, dev->name, fsm_getstate_str(grp->fsm));
+
+	switch (fsm_getstate(grp->fsm)) {
+	case MPCG_STATE_INOP:
+		/* Group is in the process of terminating */
+		grp->alloc_called = 1;
+		break;
+	case MPCG_STATE_RESET:
+		/* MPC Group will transition to state		  */
+		/* MPCG_STATE_XID2INITW iff the minimum number	  */
+		/* of 1 read and 1 write channel have successfully*/
+		/* activated					  */
+		/*fsm_newstate(grp->fsm, MPCG_STATE_XID2INITW);*/
+		if (callback)
+			grp->send_qllc_disc = 1;
+		fallthrough;
+	case MPCG_STATE_XID0IOWAIT:
+		fsm_deltimer(&grp->timer);
+		grp->outstanding_xid2 = 0;
+		grp->outstanding_xid7 = 0;
+		grp->outstanding_xid7_p2 = 0;
+		grp->saved_xid2 = NULL;
+		if (callback)
+			ctcm_open(dev);
+		fsm_event(priv->fsm, DEV_EVENT_START, dev);
+		break;
+	case MPCG_STATE_READY:
+		/* XID exchanges completed after PORT was activated */
+		/* Link station already active			    */
+		/* Maybe timing issue...retry callback		    */
+		grp->allocchan_callback_retries++;
+		if (grp->allocchan_callback_retries < 4) {
+			if (grp->allochanfunc)
+				grp->allochanfunc(grp->port_num,
+						  grp->group_max_buflen);
+		} else {
+			/* there are problems...bail out	    */
+			/* there may be a state mismatch so restart */
+			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+			grp->allocchan_callback_retries = 0;
+		}
+		break;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(ctc_mpc_alloc_channel);
+
+/*
+ * ctc_mpc_establish_connectivity
+ *	(exported interface)
+ */
+void ctc_mpc_establish_connectivity(int port_num,
+				void (*callback)(int, int, int))
+{
+	struct net_device *dev;
+	struct mpc_group *grp;
+	struct ctcm_priv *priv;
+	struct channel *rch, *wch;
+
+	dev = ctcmpc_get_dev(port_num);
+	if (dev == NULL)
+		return;
+	priv = dev->ml_priv;
+	grp = priv->mpcg;
+	rch = priv->channel[CTCM_READ];
+	wch = priv->channel[CTCM_WRITE];
+
+	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
+			"%s(%s): state=%s",
+			CTCM_FUNTAIL, dev->name, fsm_getstate_str(grp->fsm));
+
+	grp->estconnfunc = callback;
+	grp->port_num = port_num;
+
+	switch (fsm_getstate(grp->fsm)) {
+	case MPCG_STATE_READY:
+		/* XID exchanges completed after PORT was activated */
+		/* Link station already active			    */
+		/* Maybe timing issue...retry callback		    */
+		fsm_deltimer(&grp->timer);
+		grp->estconn_callback_retries++;
+		if (grp->estconn_callback_retries < 4) {
+			if (grp->estconnfunc) {
+				grp->estconnfunc(grp->port_num, 0,
+						grp->group_max_buflen);
+				grp->estconnfunc = NULL;
+			}
+		} else {
+			/* there are problems...bail out	 */
+			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+			grp->estconn_callback_retries = 0;
+		}
+		break;
+	case MPCG_STATE_INOP:
+	case MPCG_STATE_RESET:
+		/* MPC Group is not ready to start XID - min num of */
+		/* 1 read and 1 write channel have not been acquired*/
+
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): REJECTED - inactive channels",
+					CTCM_FUNTAIL, dev->name);
+		if (grp->estconnfunc) {
+			grp->estconnfunc(grp->port_num, -1, 0);
+			grp->estconnfunc = NULL;
+		}
+		break;
+	case MPCG_STATE_XID2INITW:
+		/* alloc channel was called but no XID exchange    */
+		/* has occurred. initiate xside XID exchange	   */
+		/* make sure yside XID0 processing has not started */
+
+		if ((fsm_getstate(rch->fsm) > CH_XID0_PENDING) ||
+			(fsm_getstate(wch->fsm) > CH_XID0_PENDING)) {
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): ABORT - PASSIVE XID",
+					CTCM_FUNTAIL, dev->name);
+			break;
+		}
+		grp->send_qllc_disc = 1;
+		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIT);
+		fsm_deltimer(&grp->timer);
+		fsm_addtimer(&grp->timer, MPC_XID_TIMEOUT_VALUE,
+						MPCG_EVENT_TIMER, dev);
+		grp->outstanding_xid7 = 0;
+		grp->outstanding_xid7_p2 = 0;
+		grp->saved_xid2 = NULL;
+		if ((rch->in_mpcgroup) &&
+				(fsm_getstate(rch->fsm) == CH_XID0_PENDING))
+			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, rch);
+		else {
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): RX-%s not ready for ACTIVE XID0",
+					CTCM_FUNTAIL, dev->name, rch->id);
+			if (grp->estconnfunc) {
+				grp->estconnfunc(grp->port_num, -1, 0);
+				grp->estconnfunc = NULL;
+			}
+			fsm_deltimer(&grp->timer);
+				goto done;
+		}
+		if ((wch->in_mpcgroup) &&
+				(fsm_getstate(wch->fsm) == CH_XID0_PENDING))
+			fsm_event(grp->fsm, MPCG_EVENT_XID0DO, wch);
+		else {
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): WX-%s not ready for ACTIVE XID0",
+					CTCM_FUNTAIL, dev->name, wch->id);
+			if (grp->estconnfunc) {
+				grp->estconnfunc(grp->port_num, -1, 0);
+				grp->estconnfunc = NULL;
+			}
+			fsm_deltimer(&grp->timer);
+				goto done;
+			}
+		break;
+	case MPCG_STATE_XID0IOWAIT:
+		/* already in active XID negotiations */
+	default:
+		break;
+	}
+
+done:
+	CTCM_PR_DEBUG("Exit %s()\n", __func__);
+	return;
+}
+EXPORT_SYMBOL(ctc_mpc_establish_connectivity);
+
+/*
+ * ctc_mpc_dealloc_ch
+ *	(exported interface)
+ */
+void ctc_mpc_dealloc_ch(int port_num)
+{
+	struct net_device *dev;
+	struct ctcm_priv *priv;
+	struct mpc_group *grp;
+
+	dev = ctcmpc_get_dev(port_num);
+	if (dev == NULL)
+		return;
+	priv = dev->ml_priv;
+	grp = priv->mpcg;
+
+	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_DEBUG,
+			"%s: %s: refcount = %d\n",
+			CTCM_FUNTAIL, dev->name, netdev_refcnt_read(dev));
+
+	fsm_deltimer(&priv->restart_timer);
+	grp->channels_terminating = 0;
+	fsm_deltimer(&grp->timer);
+	grp->allochanfunc = NULL;
+	grp->estconnfunc = NULL;
+	grp->port_persist = 0;
+	grp->send_qllc_disc = 0;
+	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+
+	ctcm_close(dev);
+	return;
+}
+EXPORT_SYMBOL(ctc_mpc_dealloc_ch);
+
+/*
+ * ctc_mpc_flow_control
+ *	(exported interface)
+ */
+void ctc_mpc_flow_control(int port_num, int flowc)
+{
+	struct ctcm_priv *priv;
+	struct mpc_group *grp;
+	struct net_device *dev;
+	struct channel *rch;
+	int mpcg_state;
+
+	dev = ctcmpc_get_dev(port_num);
+	if (dev == NULL)
+		return;
+	priv = dev->ml_priv;
+	grp = priv->mpcg;
+
+	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
+			"%s: %s: flowc = %d",
+				CTCM_FUNTAIL, dev->name, flowc);
+
+	rch = priv->channel[CTCM_READ];
+
+	mpcg_state = fsm_getstate(grp->fsm);
+	switch (flowc) {
+	case 1:
+		if (mpcg_state == MPCG_STATE_FLOWC)
+			break;
+		if (mpcg_state == MPCG_STATE_READY) {
+			if (grp->flow_off_called == 1)
+				grp->flow_off_called = 0;
+			else
+				fsm_newstate(grp->fsm, MPCG_STATE_FLOWC);
+			break;
+		}
+		break;
+	case 0:
+		if (mpcg_state == MPCG_STATE_FLOWC) {
+			fsm_newstate(grp->fsm, MPCG_STATE_READY);
+			/* ensure any data that has accumulated */
+			/* on the io_queue will now be sen t	*/
+			tasklet_schedule(&rch->ch_tasklet);
+		}
+		/* possible race condition			*/
+		if (mpcg_state == MPCG_STATE_READY) {
+			grp->flow_off_called = 1;
+			break;
+		}
+		break;
+	}
+
+}
+EXPORT_SYMBOL(ctc_mpc_flow_control);
+
+static int mpc_send_qllc_discontact(struct net_device *);
+
+/*
+ * helper function of ctcmpc_unpack_skb
+*/
+static void mpc_rcvd_sweep_resp(struct mpcg_info *mpcginfo)
+{
+	struct channel	  *rch = mpcginfo->ch;
+	struct net_device *dev = rch->netdev;
+	struct ctcm_priv   *priv = dev->ml_priv;
+	struct mpc_group  *grp = priv->mpcg;
+	struct channel	  *ch = priv->channel[CTCM_WRITE];
+
+	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, ch, ch->id);
+	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
+
+	grp->sweep_rsp_pend_num--;
+
+	if ((grp->sweep_req_pend_num == 0) &&
+			(grp->sweep_rsp_pend_num == 0)) {
+		fsm_deltimer(&ch->sweep_timer);
+		grp->in_sweep = 0;
+		rch->th_seq_num = 0x00;
+		ch->th_seq_num = 0x00;
+		ctcm_clear_busy_do(dev);
+	}
+
+	return;
+
+}
+
+/*
+ * helper function of mpc_rcvd_sweep_req
+ * which is a helper of ctcmpc_unpack_skb
+ */
+static void ctcmpc_send_sweep_resp(struct channel *rch)
+{
+	struct net_device *dev = rch->netdev;
+	struct ctcm_priv *priv = dev->ml_priv;
+	struct mpc_group *grp = priv->mpcg;
+	struct th_sweep *header;
+	struct sk_buff *sweep_skb;
+	struct channel *ch  = priv->channel[CTCM_WRITE];
+
+	CTCM_PR_DEBUG("%s: ch=0x%p id=%s\n", __func__, rch, rch->id);
+
+	sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
+	if (sweep_skb == NULL) {
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): sweep_skb allocation ERROR\n",
+			CTCM_FUNTAIL, rch->id);
+		goto done;
+	}
+
+	header = kmalloc(sizeof(struct th_sweep), gfp_type());
+
+	if (!header) {
+		dev_kfree_skb_any(sweep_skb);
+		goto done;
+	}
+
+	header->th.th_seg	= 0x00 ;
+	header->th.th_ch_flag	= TH_SWEEP_RESP;
+	header->th.th_blk_flag	= 0x00;
+	header->th.th_is_xid	= 0x00;
+	header->th.th_seq_num	= 0x00;
+	header->sw.th_last_seq	= ch->th_seq_num;
+
+	skb_put_data(sweep_skb, header, TH_SWEEP_LENGTH);
+
+	kfree(header);
+
+	netif_trans_update(dev);
+	skb_queue_tail(&ch->sweep_queue, sweep_skb);
+
+	fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
+
+	return;
+
+done:
+	grp->in_sweep = 0;
+	ctcm_clear_busy_do(dev);
+	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+
+	return;
+}
+
+/*
+ * helper function of ctcmpc_unpack_skb
+ */
+static void mpc_rcvd_sweep_req(struct mpcg_info *mpcginfo)
+{
+	struct channel	  *rch     = mpcginfo->ch;
+	struct net_device *dev     = rch->netdev;
+	struct ctcm_priv  *priv = dev->ml_priv;
+	struct mpc_group  *grp  = priv->mpcg;
+	struct channel	  *ch	   = priv->channel[CTCM_WRITE];
+
+	if (do_debug)
+		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
+			" %s(): ch=0x%p id=%s\n", __func__, ch, ch->id);
+
+	if (grp->in_sweep == 0) {
+		grp->in_sweep = 1;
+		ctcm_test_and_set_busy(dev);
+		grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
+		grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
+	}
+
+	CTCM_D3_DUMP((char *)mpcginfo->sweep, TH_SWEEP_LENGTH);
+
+	grp->sweep_req_pend_num--;
+	ctcmpc_send_sweep_resp(ch);
+	kfree(mpcginfo);
+	return;
+}
+
+/*
+  * MPC Group Station FSM definitions
+ */
+static const char *mpcg_event_names[] = {
+	[MPCG_EVENT_INOP]	= "INOP Condition",
+	[MPCG_EVENT_DISCONC]	= "Discontact Received",
+	[MPCG_EVENT_XID0DO]	= "Channel Active - Start XID",
+	[MPCG_EVENT_XID2]	= "XID2 Received",
+	[MPCG_EVENT_XID2DONE]	= "XID0 Complete",
+	[MPCG_EVENT_XID7DONE]	= "XID7 Complete",
+	[MPCG_EVENT_TIMER]	= "XID Setup Timer",
+	[MPCG_EVENT_DOIO]	= "XID DoIO",
+};
+
+static const char *mpcg_state_names[] = {
+	[MPCG_STATE_RESET]	= "Reset",
+	[MPCG_STATE_INOP]	= "INOP",
+	[MPCG_STATE_XID2INITW]	= "Passive XID- XID0 Pending Start",
+	[MPCG_STATE_XID2INITX]	= "Passive XID- XID0 Pending Complete",
+	[MPCG_STATE_XID7INITW]	= "Passive XID- XID7 Pending P1 Start",
+	[MPCG_STATE_XID7INITX]	= "Passive XID- XID7 Pending P2 Complete",
+	[MPCG_STATE_XID0IOWAIT]	= "Active  XID- XID0 Pending Start",
+	[MPCG_STATE_XID0IOWAIX]	= "Active  XID- XID0 Pending Complete",
+	[MPCG_STATE_XID7INITI]	= "Active  XID- XID7 Pending Start",
+	[MPCG_STATE_XID7INITZ]	= "Active  XID- XID7 Pending Complete ",
+	[MPCG_STATE_XID7INITF]	= "XID        - XID7 Complete ",
+	[MPCG_STATE_FLOWC]	= "FLOW CONTROL ON",
+	[MPCG_STATE_READY]	= "READY",
+};
+
+/*
+ * The MPC Group Station FSM
+ *   22 events
+ */
+static const fsm_node mpcg_fsm[] = {
+	{ MPCG_STATE_RESET,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_INOP,	MPCG_EVENT_INOP,	mpc_action_nop        },
+	{ MPCG_STATE_FLOWC,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+
+	{ MPCG_STATE_READY,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
+	{ MPCG_STATE_READY,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+
+	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
+	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
+	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
+	{ MPCG_STATE_XID2INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
+
+	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
+	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
+	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
+	{ MPCG_STATE_XID2INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
+
+	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
+	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
+	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
+	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
+	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
+	{ MPCG_STATE_XID7INITW,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
+
+	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
+	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
+	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
+	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
+	{ MPCG_STATE_XID7INITX,	MPCG_EVENT_DOIO,	mpc_action_yside_xid  },
+
+	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
+	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DISCONC,	mpc_action_discontact },
+	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
+	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_TIMER,	mpc_action_timeout    },
+	{ MPCG_STATE_XID0IOWAIT, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
+
+	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID0DO,	mpc_action_doxid0     },
+	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DISCONC,	mpc_action_discontact },
+	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_XID2,	mpc_action_rcvd_xid0  },
+	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_TIMER,	mpc_action_timeout    },
+	{ MPCG_STATE_XID0IOWAIX, MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
+
+	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2DONE,	mpc_action_doxid7     },
+	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
+	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
+	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
+	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
+	{ MPCG_STATE_XID7INITI,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
+
+	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID2,	mpc_action_rcvd_xid7  },
+	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_XID7DONE,	mpc_action_doxid7     },
+	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DISCONC,	mpc_action_discontact },
+	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_TIMER,	mpc_action_timeout    },
+	{ MPCG_STATE_XID7INITZ,	MPCG_EVENT_DOIO,	mpc_action_xside_xid  },
+
+	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_INOP,	mpc_action_go_inop    },
+	{ MPCG_STATE_XID7INITF,	MPCG_EVENT_XID7DONE,	mpc_action_go_ready   },
+};
+
+static int mpcg_fsm_len = ARRAY_SIZE(mpcg_fsm);
+
+/*
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ */
+static void mpc_action_go_ready(fsm_instance *fsm, int event, void *arg)
+{
+	struct net_device *dev = arg;
+	struct ctcm_priv *priv = dev->ml_priv;
+	struct mpc_group *grp = priv->mpcg;
+
+	if (grp == NULL) {
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): No MPC group",
+				CTCM_FUNTAIL, dev->name);
+		return;
+	}
+
+	fsm_deltimer(&grp->timer);
+
+	if (grp->saved_xid2->xid2_flag2 == 0x40) {
+		priv->xid->xid2_flag2 = 0x00;
+		if (grp->estconnfunc) {
+			grp->estconnfunc(grp->port_num, 1,
+					grp->group_max_buflen);
+			grp->estconnfunc = NULL;
+		} else if (grp->allochanfunc)
+			grp->send_qllc_disc = 1;
+
+		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): fails",
+					CTCM_FUNTAIL, dev->name);
+		return;
+	}
+
+	grp->port_persist = 1;
+	grp->out_of_sequence = 0;
+	grp->estconn_called = 0;
+
+	tasklet_hi_schedule(&grp->mpc_tasklet2);
+
+	return;
+}
+
+/*
+ * helper of ctcm_init_netdevice
+ * CTCM_PROTO_MPC only
+ */
+void mpc_group_ready(unsigned long adev)
+{
+	struct net_device *dev = (struct net_device *)adev;
+	struct ctcm_priv *priv = dev->ml_priv;
+	struct mpc_group *grp = priv->mpcg;
+	struct channel *ch = NULL;
+
+	if (grp == NULL) {
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): No MPC group",
+				CTCM_FUNTAIL, dev->name);
+		return;
+	}
+
+	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
+		"%s: %s: GROUP TRANSITIONED TO READY, maxbuf = %d\n",
+			CTCM_FUNTAIL, dev->name, grp->group_max_buflen);
+
+	fsm_newstate(grp->fsm, MPCG_STATE_READY);
+
+	/* Put up a read on the channel */
+	ch = priv->channel[CTCM_READ];
+	ch->pdu_seq = 0;
+	CTCM_PR_DBGDATA("ctcmpc: %s() ToDCM_pdu_seq= %08x\n" ,
+			__func__, ch->pdu_seq);
+
+	ctcmpc_chx_rxidle(ch->fsm, CTC_EVENT_START, ch);
+	/* Put the write channel in idle state */
+	ch = priv->channel[CTCM_WRITE];
+	if (ch->collect_len > 0) {
+		spin_lock(&ch->collect_lock);
+		ctcm_purge_skb_queue(&ch->collect_queue);
+		ch->collect_len = 0;
+		spin_unlock(&ch->collect_lock);
+	}
+	ctcm_chx_txidle(ch->fsm, CTC_EVENT_START, ch);
+	ctcm_clear_busy(dev);
+
+	if (grp->estconnfunc) {
+		grp->estconnfunc(grp->port_num, 0,
+				    grp->group_max_buflen);
+		grp->estconnfunc = NULL;
+	} else 	if (grp->allochanfunc)
+		grp->allochanfunc(grp->port_num, grp->group_max_buflen);
+
+	grp->send_qllc_disc = 1;
+	grp->changed_side = 0;
+
+	return;
+
+}
+
+/*
+ * Increment the MPC Group Active Channel Counts
+ * helper of dev_action (called from channel fsm)
+ */
+void mpc_channel_action(struct channel *ch, int direction, int action)
+{
+	struct net_device  *dev  = ch->netdev;
+	struct ctcm_priv   *priv = dev->ml_priv;
+	struct mpc_group   *grp  = priv->mpcg;
+
+	if (grp == NULL) {
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): No MPC group",
+				CTCM_FUNTAIL, dev->name);
+		return;
+	}
+
+	CTCM_PR_DEBUG("enter %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
+
+	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
+		"%s: %i / Grp:%s total_channels=%i, active_channels: "
+		"read=%i, write=%i\n", __func__, action,
+		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
+		grp->active_channels[CTCM_READ],
+		grp->active_channels[CTCM_WRITE]);
+
+	if ((action == MPC_CHANNEL_ADD) && (ch->in_mpcgroup == 0)) {
+		grp->num_channel_paths++;
+		grp->active_channels[direction]++;
+		grp->outstanding_xid2++;
+		ch->in_mpcgroup = 1;
+
+		if (ch->xid_skb != NULL)
+			dev_kfree_skb_any(ch->xid_skb);
+
+		ch->xid_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT,
+					GFP_ATOMIC | GFP_DMA);
+		if (ch->xid_skb == NULL) {
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): Couldn't alloc ch xid_skb\n",
+				CTCM_FUNTAIL, dev->name);
+			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+			return;
+		}
+		ch->xid_skb_data = ch->xid_skb->data;
+		ch->xid_th = (struct th_header *)ch->xid_skb->data;
+		skb_put(ch->xid_skb, TH_HEADER_LENGTH);
+		ch->xid = (struct xid2 *)skb_tail_pointer(ch->xid_skb);
+		skb_put(ch->xid_skb, XID2_LENGTH);
+		ch->xid_id = skb_tail_pointer(ch->xid_skb);
+		ch->xid_skb->data = ch->xid_skb_data;
+		skb_reset_tail_pointer(ch->xid_skb);
+		ch->xid_skb->len = 0;
+
+		skb_put_data(ch->xid_skb, grp->xid_skb->data,
+			     grp->xid_skb->len);
+
+		ch->xid->xid2_dlc_type =
+			((CHANNEL_DIRECTION(ch->flags) == CTCM_READ)
+				? XID2_READ_SIDE : XID2_WRITE_SIDE);
+
+		if (CHANNEL_DIRECTION(ch->flags) == CTCM_WRITE)
+			ch->xid->xid2_buf_len = 0x00;
+
+		ch->xid_skb->data = ch->xid_skb_data;
+		skb_reset_tail_pointer(ch->xid_skb);
+		ch->xid_skb->len = 0;
+
+		fsm_newstate(ch->fsm, CH_XID0_PENDING);
+
+		if ((grp->active_channels[CTCM_READ] > 0) &&
+		    (grp->active_channels[CTCM_WRITE] > 0) &&
+			(fsm_getstate(grp->fsm) < MPCG_STATE_XID2INITW)) {
+			fsm_newstate(grp->fsm, MPCG_STATE_XID2INITW);
+			CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_NOTICE,
+				"%s: %s: MPC GROUP CHANNELS ACTIVE\n",
+						__func__, dev->name);
+		}
+	} else if ((action == MPC_CHANNEL_REMOVE) &&
+			(ch->in_mpcgroup == 1)) {
+		ch->in_mpcgroup = 0;
+		grp->num_channel_paths--;
+		grp->active_channels[direction]--;
+
+		if (ch->xid_skb != NULL)
+			dev_kfree_skb_any(ch->xid_skb);
+		ch->xid_skb = NULL;
+
+		if (grp->channels_terminating)
+					goto done;
+
+		if (((grp->active_channels[CTCM_READ] == 0) &&
+					(grp->active_channels[CTCM_WRITE] > 0))
+			|| ((grp->active_channels[CTCM_WRITE] == 0) &&
+					(grp->active_channels[CTCM_READ] > 0)))
+			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+	}
+done:
+	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
+		"exit %s: %i / Grp:%s total_channels=%i, active_channels: "
+		"read=%i, write=%i\n", __func__, action,
+		fsm_getstate_str(grp->fsm), grp->num_channel_paths,
+		grp->active_channels[CTCM_READ],
+		grp->active_channels[CTCM_WRITE]);
+
+	CTCM_PR_DEBUG("exit %s: ch=0x%p id=%s\n", __func__, ch, ch->id);
+}
+
+/**
+ * Unpack a just received skb and hand it over to
+ * upper layers.
+ * special MPC version of unpack_skb.
+ *
+ * ch		The channel where this skb has been received.
+ * pskb		The received skb.
+ */
+static void ctcmpc_unpack_skb(struct channel *ch, struct sk_buff *pskb)
+{
+	struct net_device *dev	= ch->netdev;
+	struct ctcm_priv *priv = dev->ml_priv;
+	struct mpc_group *grp = priv->mpcg;
+	struct pdu *curr_pdu;
+	struct mpcg_info *mpcginfo;
+	struct th_header *header = NULL;
+	struct th_sweep *sweep = NULL;
+	int pdu_last_seen = 0;
+	__u32 new_len;
+	struct sk_buff *skb;
+	int skblen;
+	int sendrc = 0;
+
+	CTCM_PR_DEBUG("ctcmpc enter: %s() %s cp:%i ch:%s\n",
+			__func__, dev->name, smp_processor_id(), ch->id);
+
+	header = (struct th_header *)pskb->data;
+	if ((header->th_seg == 0) &&
+		(header->th_ch_flag == 0) &&
+		(header->th_blk_flag == 0) &&
+		(header->th_seq_num == 0))
+		/* nothing for us */	goto done;
+
+	CTCM_PR_DBGDATA("%s: th_header\n", __func__);
+	CTCM_D3_DUMP((char *)header, TH_HEADER_LENGTH);
+	CTCM_PR_DBGDATA("%s: pskb len: %04x \n", __func__, pskb->len);
+
+	pskb->dev = dev;
+	pskb->ip_summed = CHECKSUM_UNNECESSARY;
+	skb_pull(pskb, TH_HEADER_LENGTH);
+
+	if (likely(header->th_ch_flag == TH_HAS_PDU)) {
+		CTCM_PR_DBGDATA("%s: came into th_has_pdu\n", __func__);
+		if ((fsm_getstate(grp->fsm) == MPCG_STATE_FLOWC) ||
+		   ((fsm_getstate(grp->fsm) == MPCG_STATE_READY) &&
+		    (header->th_seq_num != ch->th_seq_num + 1) &&
+		    (ch->th_seq_num != 0))) {
+			/* This is NOT the next segment		*
+			 * we are not the correct race winner	*
+			 * go away and let someone else win	*
+			 * BUT..this only applies if xid negot	*
+			 * is done				*
+			*/
+			grp->out_of_sequence += 1;
+			__skb_push(pskb, TH_HEADER_LENGTH);
+			skb_queue_tail(&ch->io_queue, pskb);
+			CTCM_PR_DBGDATA("%s: th_seq_num expect:%08x "
+					"got:%08x\n", __func__,
+				ch->th_seq_num + 1, header->th_seq_num);
+
+			return;
+		}
+		grp->out_of_sequence = 0;
+		ch->th_seq_num = header->th_seq_num;
+
+		CTCM_PR_DBGDATA("ctcmpc: %s() FromVTAM_th_seq=%08x\n",
+					__func__, ch->th_seq_num);
+
+		if (unlikely(fsm_getstate(grp->fsm) != MPCG_STATE_READY))
+					goto done;
+		while ((pskb->len > 0) && !pdu_last_seen) {
+			curr_pdu = (struct pdu *)pskb->data;
+
+			CTCM_PR_DBGDATA("%s: pdu_header\n", __func__);
+			CTCM_D3_DUMP((char *)pskb->data, PDU_HEADER_LENGTH);
+			CTCM_PR_DBGDATA("%s: pskb len: %04x \n",
+						__func__, pskb->len);
+
+			skb_pull(pskb, PDU_HEADER_LENGTH);
+
+			if (curr_pdu->pdu_flag & PDU_LAST)
+				pdu_last_seen = 1;
+			if (curr_pdu->pdu_flag & PDU_CNTL)
+				pskb->protocol = htons(ETH_P_SNAP);
+			else
+				pskb->protocol = htons(ETH_P_SNA_DIX);
+
+			if ((pskb->len <= 0) || (pskb->len > ch->max_bufsize)) {
+				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+					"%s(%s): Dropping packet with "
+					"illegal siize %d",
+					CTCM_FUNTAIL, dev->name, pskb->len);
+
+				priv->stats.rx_dropped++;
+				priv->stats.rx_length_errors++;
+					goto done;
+			}
+			skb_reset_mac_header(pskb);
+			new_len = curr_pdu->pdu_offset;
+			CTCM_PR_DBGDATA("%s: new_len: %04x \n",
+						__func__, new_len);
+			if ((new_len == 0) || (new_len > pskb->len)) {
+				/* should never happen		    */
+				/* pskb len must be hosed...bail out */
+				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+					"%s(%s): non valid pdu_offset: %04x",
+					/* "data may be lost", */
+					CTCM_FUNTAIL, dev->name, new_len);
+				goto done;
+			}
+			skb = __dev_alloc_skb(new_len+4, GFP_ATOMIC);
+
+			if (!skb) {
+				CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+					"%s(%s): MEMORY allocation error",
+						CTCM_FUNTAIL, dev->name);
+				priv->stats.rx_dropped++;
+				fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+						goto done;
+			}
+			skb_put_data(skb, pskb->data, new_len);
+
+			skb_reset_mac_header(skb);
+			skb->dev = pskb->dev;
+			skb->protocol = pskb->protocol;
+			skb->ip_summed = CHECKSUM_UNNECESSARY;
+			*((__u32 *) skb_push(skb, 4)) = ch->pdu_seq;
+			ch->pdu_seq++;
+
+			if (do_debug_data) {
+				ctcm_pr_debug("%s: ToDCM_pdu_seq= %08x\n",
+						__func__, ch->pdu_seq);
+				ctcm_pr_debug("%s: skb:%0lx "
+					"skb len: %d \n", __func__,
+					(unsigned long)skb, skb->len);
+				ctcm_pr_debug("%s: up to 32 bytes "
+					"of pdu_data sent\n", __func__);
+				ctcmpc_dump32((char *)skb->data, skb->len);
+			}
+
+			skblen = skb->len;
+			sendrc = netif_rx(skb);
+			priv->stats.rx_packets++;
+			priv->stats.rx_bytes += skblen;
+			skb_pull(pskb, new_len); /* point to next PDU */
+		}
+	} else {
+		mpcginfo = kmalloc(sizeof(struct mpcg_info), gfp_type());
+		if (mpcginfo == NULL)
+					goto done;
+
+		mpcginfo->ch = ch;
+		mpcginfo->th = header;
+		mpcginfo->skb = pskb;
+		CTCM_PR_DEBUG("%s: Not PDU - may be control pkt\n",
+					__func__);
+		/*  it's a sweep?   */
+		sweep = (struct th_sweep *)pskb->data;
+		mpcginfo->sweep = sweep;
+		if (header->th_ch_flag == TH_SWEEP_REQ)
+			mpc_rcvd_sweep_req(mpcginfo);
+		else if (header->th_ch_flag == TH_SWEEP_RESP)
+			mpc_rcvd_sweep_resp(mpcginfo);
+		else if (header->th_blk_flag == TH_DATA_IS_XID) {
+			struct xid2 *thisxid = (struct xid2 *)pskb->data;
+			skb_pull(pskb, XID2_LENGTH);
+			mpcginfo->xid = thisxid;
+			fsm_event(grp->fsm, MPCG_EVENT_XID2, mpcginfo);
+		} else if (header->th_blk_flag == TH_DISCONTACT)
+			fsm_event(grp->fsm, MPCG_EVENT_DISCONC, mpcginfo);
+		else if (header->th_seq_num != 0) {
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): control pkt expected\n",
+						CTCM_FUNTAIL, dev->name);
+			priv->stats.rx_dropped++;
+			/* mpcginfo only used for non-data transfers */
+			if (do_debug_data)
+				ctcmpc_dump_skb(pskb, -8);
+		}
+		kfree(mpcginfo);
+	}
+done:
+
+	dev_kfree_skb_any(pskb);
+	if (sendrc == NET_RX_DROP) {
+		dev_warn(&dev->dev,
+			"The network backlog for %s is exceeded, "
+			"package dropped\n", __func__);
+		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+	}
+
+	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
+			__func__, dev->name, ch, ch->id);
+}
+
+/**
+ * tasklet helper for mpc's skb unpacking.
+ *
+ * ch		The channel to work on.
+ * Allow flow control back pressure to occur here.
+ * Throttling back channel can result in excessive
+ * channel inactivity and system deact of channel
+ */
+void ctcmpc_bh(unsigned long thischan)
+{
+	struct channel	  *ch	= (struct channel *)thischan;
+	struct sk_buff	  *skb;
+	struct net_device *dev	= ch->netdev;
+	struct ctcm_priv  *priv	= dev->ml_priv;
+	struct mpc_group  *grp	= priv->mpcg;
+
+	CTCM_PR_DEBUG("%s cp:%i enter:  %s() %s\n",
+	       dev->name, smp_processor_id(), __func__, ch->id);
+	/* caller has requested driver to throttle back */
+	while ((fsm_getstate(grp->fsm) != MPCG_STATE_FLOWC) &&
+			(skb = skb_dequeue(&ch->io_queue))) {
+		ctcmpc_unpack_skb(ch, skb);
+		if (grp->out_of_sequence > 20) {
+			/* assume data loss has occurred if */
+			/* missing seq_num for extended     */
+			/* period of time		    */
+			grp->out_of_sequence = 0;
+			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+			break;
+		}
+		if (skb == skb_peek(&ch->io_queue))
+			break;
+	}
+	CTCM_PR_DEBUG("exit %s: %s: ch=0x%p id=%s\n",
+			__func__, dev->name, ch, ch->id);
+	return;
+}
+
+/*
+ *  MPC Group Initializations
+ */
+struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv)
+{
+	struct mpc_group *grp;
+
+	CTCM_DBF_TEXT_(MPC_SETUP, CTC_DBF_INFO,
+			"Enter %s(%p)", CTCM_FUNTAIL, priv);
+
+	grp = kzalloc(sizeof(struct mpc_group), GFP_KERNEL);
+	if (grp == NULL)
+		return NULL;
+
+	grp->fsm = init_fsm("mpcg", mpcg_state_names, mpcg_event_names,
+			MPCG_NR_STATES, MPCG_NR_EVENTS, mpcg_fsm,
+			mpcg_fsm_len, GFP_KERNEL);
+	if (grp->fsm == NULL) {
+		kfree(grp);
+		return NULL;
+	}
+
+	fsm_newstate(grp->fsm, MPCG_STATE_RESET);
+	fsm_settimer(grp->fsm, &grp->timer);
+
+	grp->xid_skb =
+		 __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC | GFP_DMA);
+	if (grp->xid_skb == NULL) {
+		kfree_fsm(grp->fsm);
+		kfree(grp);
+		return NULL;
+	}
+	/*  base xid for all channels in group  */
+	grp->xid_skb_data = grp->xid_skb->data;
+	grp->xid_th = (struct th_header *)grp->xid_skb->data;
+	skb_put_data(grp->xid_skb, &thnorm, TH_HEADER_LENGTH);
+
+	grp->xid = (struct xid2 *)skb_tail_pointer(grp->xid_skb);
+	skb_put_data(grp->xid_skb, &init_xid, XID2_LENGTH);
+	grp->xid->xid2_adj_id = jiffies | 0xfff00000;
+	grp->xid->xid2_sender_id = jiffies;
+
+	grp->xid_id = skb_tail_pointer(grp->xid_skb);
+	skb_put_data(grp->xid_skb, "VTAM", 4);
+
+	grp->rcvd_xid_skb =
+		__dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
+	if (grp->rcvd_xid_skb == NULL) {
+		kfree_fsm(grp->fsm);
+		dev_kfree_skb(grp->xid_skb);
+		kfree(grp);
+		return NULL;
+	}
+	grp->rcvd_xid_data = grp->rcvd_xid_skb->data;
+	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
+	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
+	grp->saved_xid2 = NULL;
+	priv->xid = grp->xid;
+	priv->mpcg = grp;
+	return grp;
+}
+
+/*
+ * The MPC Group Station FSM
+ */
+
+/*
+ * MPC Group Station FSM actions
+ * CTCM_PROTO_MPC only
+ */
+
+/**
+ * NOP action for statemachines
+ */
+static void mpc_action_nop(fsm_instance *fi, int event, void *arg)
+{
+}
+
+/*
+ * invoked when the device transitions to dev_stopped
+ * MPC will stop each individual channel if a single XID failure
+ * occurs, or will intitiate all channels be stopped if a GROUP
+ * level failure occurs.
+ */
+static void mpc_action_go_inop(fsm_instance *fi, int event, void *arg)
+{
+	struct net_device  *dev = arg;
+	struct ctcm_priv    *priv;
+	struct mpc_group *grp;
+	struct channel *wch;
+
+	CTCM_PR_DEBUG("Enter %s: %s\n",	__func__, dev->name);
+
+	priv  = dev->ml_priv;
+	grp =  priv->mpcg;
+	grp->flow_off_called = 0;
+	fsm_deltimer(&grp->timer);
+	if (grp->channels_terminating)
+			return;
+
+	grp->channels_terminating = 1;
+	grp->saved_state = fsm_getstate(grp->fsm);
+	fsm_newstate(grp->fsm, MPCG_STATE_INOP);
+	if (grp->saved_state > MPCG_STATE_XID7INITF)
+		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
+			"%s(%s): MPC GROUP INOPERATIVE",
+				CTCM_FUNTAIL, dev->name);
+	if ((grp->saved_state != MPCG_STATE_RESET) ||
+		/* dealloc_channel has been called */
+		(grp->port_persist == 0))
+		fsm_deltimer(&priv->restart_timer);
+
+	wch = priv->channel[CTCM_WRITE];
+
+	switch (grp->saved_state) {
+	case MPCG_STATE_RESET:
+	case MPCG_STATE_INOP:
+	case MPCG_STATE_XID2INITW:
+	case MPCG_STATE_XID0IOWAIT:
+	case MPCG_STATE_XID2INITX:
+	case MPCG_STATE_XID7INITW:
+	case MPCG_STATE_XID7INITX:
+	case MPCG_STATE_XID0IOWAIX:
+	case MPCG_STATE_XID7INITI:
+	case MPCG_STATE_XID7INITZ:
+	case MPCG_STATE_XID7INITF:
+		break;
+	case MPCG_STATE_FLOWC:
+	case MPCG_STATE_READY:
+	default:
+		tasklet_hi_schedule(&wch->ch_disc_tasklet);
+	}
+
+	grp->xid2_tgnum = 0;
+	grp->group_max_buflen = 0;  /*min of all received */
+	grp->outstanding_xid2 = 0;
+	grp->outstanding_xid7 = 0;
+	grp->outstanding_xid7_p2 = 0;
+	grp->saved_xid2 = NULL;
+	grp->xidnogood = 0;
+	grp->changed_side = 0;
+
+	grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
+	skb_reset_tail_pointer(grp->rcvd_xid_skb);
+	grp->rcvd_xid_skb->len = 0;
+	grp->rcvd_xid_th = (struct th_header *)grp->rcvd_xid_skb->data;
+	skb_put_data(grp->rcvd_xid_skb, &thnorm, TH_HEADER_LENGTH);
+
+	if (grp->send_qllc_disc == 1) {
+		grp->send_qllc_disc = 0;
+		mpc_send_qllc_discontact(dev);
+	}
+
+	/* DO NOT issue DEV_EVENT_STOP directly out of this code */
+	/* This can result in INOP of VTAM PU due to halting of  */
+	/* outstanding IO which causes a sense to be returned	 */
+	/* Only about 3 senses are allowed and then IOS/VTAM will*/
+	/* become unreachable without manual intervention	 */
+	if ((grp->port_persist == 1) || (grp->alloc_called)) {
+		grp->alloc_called = 0;
+		fsm_deltimer(&priv->restart_timer);
+		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_RESTART, dev);
+		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
+		if (grp->saved_state > MPCG_STATE_XID7INITF)
+			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
+				"%s(%s): MPC GROUP RECOVERY SCHEDULED",
+					CTCM_FUNTAIL, dev->name);
+	} else {
+		fsm_deltimer(&priv->restart_timer);
+		fsm_addtimer(&priv->restart_timer, 500, DEV_EVENT_STOP, dev);
+		fsm_newstate(grp->fsm, MPCG_STATE_RESET);
+		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ALWAYS,
+			"%s(%s): NO MPC GROUP RECOVERY ATTEMPTED",
+						CTCM_FUNTAIL, dev->name);
+	}
+}
+
+/**
+ * Handle mpc group  action timeout.
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ *
+ * fi		An instance of an mpc_group fsm.
+ * event	The event, just happened.
+ * arg		Generic pointer, casted from net_device * upon call.
+ */
+static void mpc_action_timeout(fsm_instance *fi, int event, void *arg)
+{
+	struct net_device *dev = arg;
+	struct ctcm_priv *priv;
+	struct mpc_group *grp;
+	struct channel *wch;
+	struct channel *rch;
+
+	priv = dev->ml_priv;
+	grp = priv->mpcg;
+	wch = priv->channel[CTCM_WRITE];
+	rch = priv->channel[CTCM_READ];
+
+	switch (fsm_getstate(grp->fsm)) {
+	case MPCG_STATE_XID2INITW:
+		/* Unless there is outstanding IO on the  */
+		/* channel just return and wait for ATTN  */
+		/* interrupt to begin XID negotiations	  */
+		if ((fsm_getstate(rch->fsm) == CH_XID0_PENDING) &&
+		   (fsm_getstate(wch->fsm) == CH_XID0_PENDING))
+			break;
+		fallthrough;
+	default:
+		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+	}
+
+	CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_DEBUG,
+			"%s: dev=%s exit",
+			CTCM_FUNTAIL, dev->name);
+	return;
+}
+
+/*
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ */
+void mpc_action_discontact(fsm_instance *fi, int event, void *arg)
+{
+	struct mpcg_info   *mpcginfo   = arg;
+	struct channel	   *ch	       = mpcginfo->ch;
+	struct net_device  *dev;
+	struct ctcm_priv   *priv;
+	struct mpc_group   *grp;
+
+	if (ch) {
+		dev = ch->netdev;
+		if (dev) {
+			priv = dev->ml_priv;
+			if (priv) {
+				CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
+					"%s: %s: %s\n",
+					CTCM_FUNTAIL, dev->name, ch->id);
+				grp = priv->mpcg;
+				grp->send_qllc_disc = 1;
+				fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
+			}
+		}
+	}
+
+	return;
+}
+
+/*
+ * MPC Group Station - not part of FSM
+ * CTCM_PROTO_MPC only
+ * called from add_channel in ctcm_main.c
+ */
+void mpc_action_send_discontact(unsigned long thischan)
+{
+	int rc;
+	struct channel	*ch = (struct channel *)thischan;
+	unsigned long	saveflags = 0;
+
+	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
+	rc = ccw_device_start(ch->cdev, &ch->ccw[15], 0, 0xff, 0);
+	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
+
+	if (rc != 0) {
+		ctcm_ccw_check_rc(ch, rc, (char *)__func__);
+	}
+
+	return;
+}
+
+
+/*
+ * helper function of mpc FSM
+ * CTCM_PROTO_MPC only
+ * mpc_action_rcvd_xid7
+*/
+static int mpc_validate_xid(struct mpcg_info *mpcginfo)
+{
+	struct channel	   *ch	 = mpcginfo->ch;
+	struct net_device  *dev  = ch->netdev;
+	struct ctcm_priv   *priv = dev->ml_priv;
+	struct mpc_group   *grp  = priv->mpcg;
+	struct xid2	   *xid  = mpcginfo->xid;
+	int	rc	 = 0;
+	__u64	our_id   = 0;
+	__u64   their_id = 0;
+	int	len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
+
+	CTCM_PR_DEBUG("Enter %s: xid=%p\n", __func__, xid);
+
+	if (xid == NULL) {
+		rc = 1;
+		/* XID REJECTED: xid == NULL */
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): xid = NULL",
+				CTCM_FUNTAIL, ch->id);
+			goto done;
+	}
+
+	CTCM_D3_DUMP((char *)xid, XID2_LENGTH);
+
+	/*the received direction should be the opposite of ours  */
+	if (((CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ? XID2_WRITE_SIDE :
+				XID2_READ_SIDE) != xid->xid2_dlc_type) {
+		rc = 2;
+		/* XID REJECTED: r/w channel pairing mismatch */
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): r/w channel pairing mismatch",
+				CTCM_FUNTAIL, ch->id);
+			goto done;
+	}
+
+	if (xid->xid2_dlc_type == XID2_READ_SIDE) {
+		CTCM_PR_DEBUG("%s: grpmaxbuf:%d xid2buflen:%d\n", __func__,
+				grp->group_max_buflen, xid->xid2_buf_len);
+
+		if (grp->group_max_buflen == 0 || grp->group_max_buflen >
+						xid->xid2_buf_len - len)
+			grp->group_max_buflen = xid->xid2_buf_len - len;
+	}
+
+	if (grp->saved_xid2 == NULL) {
+		grp->saved_xid2 =
+			(struct xid2 *)skb_tail_pointer(grp->rcvd_xid_skb);
+
+		skb_put_data(grp->rcvd_xid_skb, xid, XID2_LENGTH);
+		grp->rcvd_xid_skb->data = grp->rcvd_xid_data;
+
+		skb_reset_tail_pointer(grp->rcvd_xid_skb);
+		grp->rcvd_xid_skb->len = 0;
+
+		/* convert two 32 bit numbers into 1 64 bit for id compare */
+		our_id = (__u64)priv->xid->xid2_adj_id;
+		our_id = our_id << 32;
+		our_id = our_id + priv->xid->xid2_sender_id;
+		their_id = (__u64)xid->xid2_adj_id;
+		their_id = their_id << 32;
+		their_id = their_id + xid->xid2_sender_id;
+		/* lower id assume the xside role */
+		if (our_id < their_id) {
+			grp->roll = XSIDE;
+			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
+				"%s(%s): WE HAVE LOW ID - TAKE XSIDE",
+					CTCM_FUNTAIL, ch->id);
+		} else {
+			grp->roll = YSIDE;
+			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_NOTICE,
+				"%s(%s): WE HAVE HIGH ID - TAKE YSIDE",
+					CTCM_FUNTAIL, ch->id);
+		}
+
+	} else {
+		if (xid->xid2_flag4 != grp->saved_xid2->xid2_flag4) {
+			rc = 3;
+			/* XID REJECTED: xid flag byte4 mismatch */
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): xid flag byte4 mismatch",
+					CTCM_FUNTAIL, ch->id);
+		}
+		if (xid->xid2_flag2 == 0x40) {
+			rc = 4;
+			/* XID REJECTED - xid NOGOOD */
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): xid NOGOOD",
+					CTCM_FUNTAIL, ch->id);
+		}
+		if (xid->xid2_adj_id != grp->saved_xid2->xid2_adj_id) {
+			rc = 5;
+			/* XID REJECTED - Adjacent Station ID Mismatch */
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): Adjacent Station ID Mismatch",
+					CTCM_FUNTAIL, ch->id);
+		}
+		if (xid->xid2_sender_id != grp->saved_xid2->xid2_sender_id) {
+			rc = 6;
+			/* XID REJECTED - Sender Address Mismatch */
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): Sender Address Mismatch",
+					CTCM_FUNTAIL, ch->id);
+		}
+	}
+done:
+	if (rc) {
+		dev_warn(&dev->dev,
+			"The XID used in the MPC protocol is not valid, "
+			"rc = %d\n", rc);
+		priv->xid->xid2_flag2 = 0x40;
+		grp->saved_xid2->xid2_flag2 = 0x40;
+	}
+
+	return rc;
+}
+
+/*
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ */
+static void mpc_action_side_xid(fsm_instance *fsm, void *arg, int side)
+{
+	struct channel *ch = arg;
+	int rc = 0;
+	int gotlock = 0;
+	unsigned long saveflags = 0;	/* avoids compiler warning with
+					   spin_unlock_irqrestore */
+
+	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
+			__func__, smp_processor_id(), ch, ch->id);
+
+	if (ctcm_checkalloc_buffer(ch))
+					goto done;
+
+	/*
+	 * skb data-buffer referencing:
+	 */
+	ch->trans_skb->data = ch->trans_skb_data;
+	skb_reset_tail_pointer(ch->trans_skb);
+	ch->trans_skb->len = 0;
+	/* result of the previous 3 statements is NOT always
+	 * already set after ctcm_checkalloc_buffer
+	 * because of possible reuse of the trans_skb
+	 */
+	memset(ch->trans_skb->data, 0, 16);
+	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
+	/* check is main purpose here: */
+	skb_put(ch->trans_skb, TH_HEADER_LENGTH);
+	ch->rcvd_xid = (struct xid2 *)skb_tail_pointer(ch->trans_skb);
+	/* check is main purpose here: */
+	skb_put(ch->trans_skb, XID2_LENGTH);
+	ch->rcvd_xid_id = skb_tail_pointer(ch->trans_skb);
+	/* cleanup back to startpoint */
+	ch->trans_skb->data = ch->trans_skb_data;
+	skb_reset_tail_pointer(ch->trans_skb);
+	ch->trans_skb->len = 0;
+
+	/* non-checking rewrite of above skb data-buffer referencing: */
+	/*
+	memset(ch->trans_skb->data, 0, 16);
+	ch->rcvd_xid_th =  (struct th_header *)ch->trans_skb_data;
+	ch->rcvd_xid = (struct xid2 *)(ch->trans_skb_data + TH_HEADER_LENGTH);
+	ch->rcvd_xid_id = ch->trans_skb_data + TH_HEADER_LENGTH + XID2_LENGTH;
+	 */
+
+	ch->ccw[8].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+	ch->ccw[8].count	= 0;
+	ch->ccw[8].cda		= 0x00;
+
+	if (!(ch->xid_th && ch->xid && ch->xid_id))
+		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_INFO,
+			"%s(%s): xid_th=%p, xid=%p, xid_id=%p",
+			CTCM_FUNTAIL, ch->id, ch->xid_th, ch->xid, ch->xid_id);
+
+	if (side == XSIDE) {
+		/* mpc_action_xside_xid */
+		if (ch->xid_th == NULL)
+				goto done;
+		ch->ccw[9].cmd_code	= CCW_CMD_WRITE;
+		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+		ch->ccw[9].count	= TH_HEADER_LENGTH;
+		ch->ccw[9].cda		= virt_to_phys(ch->xid_th);
+
+		if (ch->xid == NULL)
+				goto done;
+		ch->ccw[10].cmd_code	= CCW_CMD_WRITE;
+		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+		ch->ccw[10].count	= XID2_LENGTH;
+		ch->ccw[10].cda		= virt_to_phys(ch->xid);
+
+		ch->ccw[11].cmd_code	= CCW_CMD_READ;
+		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+		ch->ccw[11].count	= TH_HEADER_LENGTH;
+		ch->ccw[11].cda		= virt_to_phys(ch->rcvd_xid_th);
+
+		ch->ccw[12].cmd_code	= CCW_CMD_READ;
+		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+		ch->ccw[12].count	= XID2_LENGTH;
+		ch->ccw[12].cda		= virt_to_phys(ch->rcvd_xid);
+
+		ch->ccw[13].cmd_code	= CCW_CMD_READ;
+		ch->ccw[13].cda		= virt_to_phys(ch->rcvd_xid_id);
+
+	} else { /* side == YSIDE : mpc_action_yside_xid */
+		ch->ccw[9].cmd_code	= CCW_CMD_READ;
+		ch->ccw[9].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+		ch->ccw[9].count	= TH_HEADER_LENGTH;
+		ch->ccw[9].cda		= virt_to_phys(ch->rcvd_xid_th);
+
+		ch->ccw[10].cmd_code	= CCW_CMD_READ;
+		ch->ccw[10].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+		ch->ccw[10].count	= XID2_LENGTH;
+		ch->ccw[10].cda		= virt_to_phys(ch->rcvd_xid);
+
+		if (ch->xid_th == NULL)
+				goto done;
+		ch->ccw[11].cmd_code	= CCW_CMD_WRITE;
+		ch->ccw[11].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+		ch->ccw[11].count	= TH_HEADER_LENGTH;
+		ch->ccw[11].cda		= virt_to_phys(ch->xid_th);
+
+		if (ch->xid == NULL)
+				goto done;
+		ch->ccw[12].cmd_code	= CCW_CMD_WRITE;
+		ch->ccw[12].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+		ch->ccw[12].count	= XID2_LENGTH;
+		ch->ccw[12].cda		= virt_to_phys(ch->xid);
+
+		if (ch->xid_id == NULL)
+				goto done;
+		ch->ccw[13].cmd_code	= CCW_CMD_WRITE;
+		ch->ccw[13].cda		= virt_to_phys(ch->xid_id);
+
+	}
+	ch->ccw[13].flags	= CCW_FLAG_SLI | CCW_FLAG_CC;
+	ch->ccw[13].count	= 4;
+
+	ch->ccw[14].cmd_code	= CCW_CMD_NOOP;
+	ch->ccw[14].flags	= CCW_FLAG_SLI;
+	ch->ccw[14].count	= 0;
+	ch->ccw[14].cda		= 0;
+
+	CTCM_CCW_DUMP((char *)&ch->ccw[8], sizeof(struct ccw1) * 7);
+	CTCM_D3_DUMP((char *)ch->xid_th, TH_HEADER_LENGTH);
+	CTCM_D3_DUMP((char *)ch->xid, XID2_LENGTH);
+	CTCM_D3_DUMP((char *)ch->xid_id, 4);
+
+	if (!in_irq()) {
+			 /* Such conditional locking is a known problem for
+			  * sparse because its static undeterministic.
+			  * Warnings should be ignored here. */
+		spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
+		gotlock = 1;
+	}
+
+	fsm_addtimer(&ch->timer, 5000 , CTC_EVENT_TIMER, ch);
+	rc = ccw_device_start(ch->cdev, &ch->ccw[8], 0, 0xff, 0);
+
+	if (gotlock)	/* see remark above about conditional locking */
+		spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
+
+	if (rc != 0) {
+		ctcm_ccw_check_rc(ch, rc,
+				(side == XSIDE) ? "x-side XID" : "y-side XID");
+	}
+
+done:
+	CTCM_PR_DEBUG("Exit %s: ch=0x%p id=%s\n",
+				__func__, ch, ch->id);
+	return;
+
+}
+
+/*
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ */
+static void mpc_action_xside_xid(fsm_instance *fsm, int event, void *arg)
+{
+	mpc_action_side_xid(fsm, arg, XSIDE);
+}
+
+/*
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ */
+static void mpc_action_yside_xid(fsm_instance *fsm, int event, void *arg)
+{
+	mpc_action_side_xid(fsm, arg, YSIDE);
+}
+
+/*
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ */
+static void mpc_action_doxid0(fsm_instance *fsm, int event, void *arg)
+{
+	struct channel	   *ch   = arg;
+	struct net_device  *dev  = ch->netdev;
+	struct ctcm_priv   *priv = dev->ml_priv;
+	struct mpc_group   *grp  = priv->mpcg;
+
+	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
+			__func__, smp_processor_id(), ch, ch->id);
+
+	if (ch->xid == NULL) {
+		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+			"%s(%s): ch->xid == NULL",
+				CTCM_FUNTAIL, dev->name);
+		return;
+	}
+
+	fsm_newstate(ch->fsm, CH_XID0_INPROGRESS);
+
+	ch->xid->xid2_option =	XID2_0;
+
+	switch (fsm_getstate(grp->fsm)) {
+	case MPCG_STATE_XID2INITW:
+	case MPCG_STATE_XID2INITX:
+		ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
+		break;
+	case MPCG_STATE_XID0IOWAIT:
+	case MPCG_STATE_XID0IOWAIX:
+		ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
+		break;
+	}
+
+	fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
+
+	return;
+}
+
+/*
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+*/
+static void mpc_action_doxid7(fsm_instance *fsm, int event, void *arg)
+{
+	struct net_device *dev = arg;
+	struct ctcm_priv  *priv = dev->ml_priv;
+	struct mpc_group  *grp  = NULL;
+	int direction;
+	int send = 0;
+
+	if (priv)
+		grp = priv->mpcg;
+	if (grp == NULL)
+		return;
+
+	for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
+		struct channel *ch = priv->channel[direction];
+		struct xid2 *thisxid = ch->xid;
+		ch->xid_skb->data = ch->xid_skb_data;
+		skb_reset_tail_pointer(ch->xid_skb);
+		ch->xid_skb->len = 0;
+		thisxid->xid2_option = XID2_7;
+		send = 0;
+
+		/* xid7 phase 1 */
+		if (grp->outstanding_xid7_p2 > 0) {
+			if (grp->roll == YSIDE) {
+				if (fsm_getstate(ch->fsm) == CH_XID7_PENDING1) {
+					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
+					ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
+					skb_put_data(ch->xid_skb, &thdummy,
+						     TH_HEADER_LENGTH);
+					send = 1;
+				}
+			} else if (fsm_getstate(ch->fsm) < CH_XID7_PENDING2) {
+					fsm_newstate(ch->fsm, CH_XID7_PENDING2);
+					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
+					skb_put_data(ch->xid_skb, &thnorm,
+						     TH_HEADER_LENGTH);
+					send = 1;
+			}
+		} else {
+			/* xid7 phase 2 */
+			if (grp->roll == YSIDE) {
+				if (fsm_getstate(ch->fsm) < CH_XID7_PENDING4) {
+					fsm_newstate(ch->fsm, CH_XID7_PENDING4);
+					skb_put_data(ch->xid_skb, &thnorm,
+						     TH_HEADER_LENGTH);
+					ch->ccw[8].cmd_code = CCW_CMD_WRITE_CTL;
+					send = 1;
+				}
+			} else if (fsm_getstate(ch->fsm) == CH_XID7_PENDING3) {
+				fsm_newstate(ch->fsm, CH_XID7_PENDING4);
+				ch->ccw[8].cmd_code = CCW_CMD_SENSE_CMD;
+				skb_put_data(ch->xid_skb, &thdummy,
+					     TH_HEADER_LENGTH);
+				send = 1;
+			}
+		}
+
+		if (send)
+			fsm_event(grp->fsm, MPCG_EVENT_DOIO, ch);
+	}
+
+	return;
+}
+
+/*
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ */
+static void mpc_action_rcvd_xid0(fsm_instance *fsm, int event, void *arg)
+{
+
+	struct mpcg_info   *mpcginfo  = arg;
+	struct channel	   *ch   = mpcginfo->ch;
+	struct net_device  *dev  = ch->netdev;
+	struct ctcm_priv   *priv = dev->ml_priv;
+	struct mpc_group   *grp  = priv->mpcg;
+
+	CTCM_PR_DEBUG("%s: ch-id:%s xid2:%i xid7:%i xidt_p2:%i \n",
+			__func__, ch->id, grp->outstanding_xid2,
+			grp->outstanding_xid7, grp->outstanding_xid7_p2);
+
+	if (fsm_getstate(ch->fsm) < CH_XID7_PENDING)
+		fsm_newstate(ch->fsm, CH_XID7_PENDING);
+
+	grp->outstanding_xid2--;
+	grp->outstanding_xid7++;
+	grp->outstanding_xid7_p2++;
+
+	/* must change state before validating xid to */
+	/* properly handle interim interrupts received*/
+	switch (fsm_getstate(grp->fsm)) {
+	case MPCG_STATE_XID2INITW:
+		fsm_newstate(grp->fsm, MPCG_STATE_XID2INITX);
+		mpc_validate_xid(mpcginfo);
+		break;
+	case MPCG_STATE_XID0IOWAIT:
+		fsm_newstate(grp->fsm, MPCG_STATE_XID0IOWAIX);
+		mpc_validate_xid(mpcginfo);
+		break;
+	case MPCG_STATE_XID2INITX:
+		if (grp->outstanding_xid2 == 0) {
+			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITW);
+			mpc_validate_xid(mpcginfo);
+			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
+		}
+		break;
+	case MPCG_STATE_XID0IOWAIX:
+		if (grp->outstanding_xid2 == 0) {
+			fsm_newstate(grp->fsm, MPCG_STATE_XID7INITI);
+			mpc_validate_xid(mpcginfo);
+			fsm_event(grp->fsm, MPCG_EVENT_XID2DONE, dev);
+		}
+		break;
+	}
+
+	CTCM_PR_DEBUG("ctcmpc:%s() %s xid2:%i xid7:%i xidt_p2:%i \n",
+		__func__, ch->id, grp->outstanding_xid2,
+		grp->outstanding_xid7, grp->outstanding_xid7_p2);
+	CTCM_PR_DEBUG("ctcmpc:%s() %s grpstate: %s chanstate: %s \n",
+		__func__, ch->id,
+		fsm_getstate_str(grp->fsm), fsm_getstate_str(ch->fsm));
+	return;
+
+}
+
+
+/*
+ * MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ */
+static void mpc_action_rcvd_xid7(fsm_instance *fsm, int event, void *arg)
+{
+	struct mpcg_info   *mpcginfo   = arg;
+	struct channel	   *ch	       = mpcginfo->ch;
+	struct net_device  *dev        = ch->netdev;
+	struct ctcm_priv   *priv    = dev->ml_priv;
+	struct mpc_group   *grp     = priv->mpcg;
+
+	CTCM_PR_DEBUG("Enter %s: cp=%i ch=0x%p id=%s\n",
+		__func__, smp_processor_id(), ch, ch->id);
+	CTCM_PR_DEBUG("%s: outstanding_xid7: %i, outstanding_xid7_p2: %i\n",
+		__func__, grp->outstanding_xid7, grp->outstanding_xid7_p2);
+
+	grp->outstanding_xid7--;
+	ch->xid_skb->data = ch->xid_skb_data;
+	skb_reset_tail_pointer(ch->xid_skb);
+	ch->xid_skb->len = 0;
+
+	switch (fsm_getstate(grp->fsm)) {
+	case MPCG_STATE_XID7INITI:
+		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITZ);
+		mpc_validate_xid(mpcginfo);
+		break;
+	case MPCG_STATE_XID7INITW:
+		fsm_newstate(grp->fsm, MPCG_STATE_XID7INITX);
+		mpc_validate_xid(mpcginfo);
+		break;
+	case MPCG_STATE_XID7INITZ:
+	case MPCG_STATE_XID7INITX:
+		if (grp->outstanding_xid7 == 0) {
+			if (grp->outstanding_xid7_p2 > 0) {
+				grp->outstanding_xid7 =
+					grp->outstanding_xid7_p2;
+				grp->outstanding_xid7_p2 = 0;
+			} else
+				fsm_newstate(grp->fsm, MPCG_STATE_XID7INITF);
+
+			mpc_validate_xid(mpcginfo);
+			fsm_event(grp->fsm, MPCG_EVENT_XID7DONE, dev);
+			break;
+		}
+		mpc_validate_xid(mpcginfo);
+		break;
+	}
+	return;
+}
+
+/*
+ * mpc_action helper of an MPC Group Station FSM action
+ * CTCM_PROTO_MPC only
+ */
+static int mpc_send_qllc_discontact(struct net_device *dev)
+{
+	__u32	new_len	= 0;
+	struct sk_buff   *skb;
+	struct qllc      *qllcptr;
+	struct ctcm_priv *priv = dev->ml_priv;
+	struct mpc_group *grp = priv->mpcg;
+
+	CTCM_PR_DEBUG("%s: GROUP STATE: %s\n",
+		__func__, mpcg_state_names[grp->saved_state]);
+
+	switch (grp->saved_state) {
+	/*
+	 * establish conn callback function is
+	 * preferred method to report failure
+	 */
+	case MPCG_STATE_XID0IOWAIT:
+	case MPCG_STATE_XID0IOWAIX:
+	case MPCG_STATE_XID7INITI:
+	case MPCG_STATE_XID7INITZ:
+	case MPCG_STATE_XID2INITW:
+	case MPCG_STATE_XID2INITX:
+	case MPCG_STATE_XID7INITW:
+	case MPCG_STATE_XID7INITX:
+		if (grp->estconnfunc) {
+			grp->estconnfunc(grp->port_num, -1, 0);
+			grp->estconnfunc = NULL;
+			break;
+		}
+		fallthrough;
+	case MPCG_STATE_FLOWC:
+	case MPCG_STATE_READY:
+		grp->send_qllc_disc = 2;
+		new_len = sizeof(struct qllc);
+		qllcptr = kzalloc(new_len, gfp_type() | GFP_DMA);
+		if (qllcptr == NULL) {
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): qllcptr allocation error",
+						CTCM_FUNTAIL, dev->name);
+			return -ENOMEM;
+		}
+
+		qllcptr->qllc_address = 0xcc;
+		qllcptr->qllc_commands = 0x03;
+
+		skb = __dev_alloc_skb(new_len, GFP_ATOMIC);
+
+		if (skb == NULL) {
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): skb allocation error",
+						CTCM_FUNTAIL, dev->name);
+			priv->stats.rx_dropped++;
+			kfree(qllcptr);
+			return -ENOMEM;
+		}
+
+		skb_put_data(skb, qllcptr, new_len);
+		kfree(qllcptr);
+
+		if (skb_headroom(skb) < 4) {
+			CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
+				"%s(%s): skb_headroom error",
+						CTCM_FUNTAIL, dev->name);
+			dev_kfree_skb_any(skb);
+			return -ENOMEM;
+		}
+
+		*((__u32 *)skb_push(skb, 4)) =
+			priv->channel[CTCM_READ]->pdu_seq;
+		priv->channel[CTCM_READ]->pdu_seq++;
+		CTCM_PR_DBGDATA("ctcmpc: %s ToDCM_pdu_seq= %08x\n",
+				__func__, priv->channel[CTCM_READ]->pdu_seq);
+
+		/* receipt of CC03 resets anticipated sequence number on
+		      receiving side */
+		priv->channel[CTCM_READ]->pdu_seq = 0x00;
+		skb_reset_mac_header(skb);
+		skb->dev = dev;
+		skb->protocol = htons(ETH_P_SNAP);
+		skb->ip_summed = CHECKSUM_UNNECESSARY;
+
+		CTCM_D3_DUMP(skb->data, (sizeof(struct qllc) + 4));
+
+		netif_rx(skb);
+		break;
+	default:
+		break;
+
+	}
+
+	return 0;
+}
+/* --- This is the END my friend --- */
+