Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / s390 / net / ctcm_mpc.c
diff --git a/kernel/drivers/s390/net/ctcm_mpc.c b/kernel/drivers/s390/net/ctcm_mpc.c
new file mode 100644 (file)
index 0000000..edf16bf
--- /dev/null
@@ -0,0 +1,2162 @@
+/*
+ *     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;
+       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);
+       }
+
+       kfree(mpcginfo);
+
+       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;
+
+       memcpy(skb_put(sweep_skb, TH_SWEEP_LENGTH), header, TH_SWEEP_LENGTH);
+
+       kfree(header);
+
+       dev->trans_start = jiffies;
+       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;
+
+               memcpy(skb_put(ch->xid_skb, grp->xid_skb->len),
+                               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;
+                       }
+                       memcpy(skb_put(skb, new_len), 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 */
+                       kfree(mpcginfo);
+                       if (do_debug_data)
+                               ctcmpc_dump_skb(pskb, -8);
+               }
+       }
+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;
+       memcpy(skb_put(grp->xid_skb, TH_HEADER_LENGTH),
+                       &thnorm, TH_HEADER_LENGTH);
+
+       grp->xid = (struct xid2 *)skb_tail_pointer(grp->xid_skb);
+       memcpy(skb_put(grp->xid_skb, XID2_LENGTH), &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);
+       memcpy(skb_put(grp->xid_skb, 4), "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;
+       memcpy(skb_put(grp->rcvd_xid_skb, TH_HEADER_LENGTH),
+                       &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;
+       memcpy(skb_put(grp->rcvd_xid_skb, TH_HEADER_LENGTH), &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;
+       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],
+                                       (unsigned long)ch, 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);
+
+               memcpy(skb_put(grp->rcvd_xid_skb,
+                                       XID2_LENGTH), 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],
+                               (unsigned long)ch, 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;
+                                       memcpy(skb_put(ch->xid_skb,
+                                                       TH_HEADER_LENGTH),
+                                              &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;
+                                       memcpy(skb_put(ch->xid_skb,
+                                                      TH_HEADER_LENGTH),
+                                              &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);
+                                       memcpy(skb_put(ch->xid_skb,
+                                                      TH_HEADER_LENGTH),
+                                              &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;
+                               memcpy(skb_put(ch->xid_skb, TH_HEADER_LENGTH),
+                                               &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;
+       }
+       kfree(mpcginfo);
+
+       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;
+       }
+       kfree(mpcginfo);
+       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;
+               }
+       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;
+               }
+
+               memcpy(skb_put(skb, new_len), 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 --- */
+