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v5.9
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright IBM Corp. 2001, 2009
   4 * Author(s):
   5 *	Original CTC driver(s):
   6 *		Fritz Elfert (felfert@millenux.com)
   7 *		Dieter Wellerdiek (wel@de.ibm.com)
   8 *		Martin Schwidefsky (schwidefsky@de.ibm.com)
   9 *		Denis Joseph Barrow (barrow_dj@yahoo.com)
  10 *		Jochen Roehrig (roehrig@de.ibm.com)
  11 *		Cornelia Huck <cornelia.huck@de.ibm.com>
  12 *	MPC additions:
  13 *		Belinda Thompson (belindat@us.ibm.com)
  14 *		Andy Richter (richtera@us.ibm.com)
  15 *	Revived by:
  16 *		Peter Tiedemann (ptiedem@de.ibm.com)
  17 */
  18
  19#undef DEBUG
  20#undef DEBUGDATA
  21#undef DEBUGCCW
  22
  23#define KMSG_COMPONENT "ctcm"
  24#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  25
  26#include <linux/module.h>
  27#include <linux/init.h>
  28#include <linux/kernel.h>
  29#include <linux/slab.h>
  30#include <linux/errno.h>
  31#include <linux/types.h>
  32#include <linux/interrupt.h>
  33#include <linux/timer.h>
  34#include <linux/bitops.h>
  35
  36#include <linux/signal.h>
  37#include <linux/string.h>
  38
  39#include <linux/ip.h>
  40#include <linux/if_arp.h>
  41#include <linux/tcp.h>
  42#include <linux/skbuff.h>
  43#include <linux/ctype.h>
  44#include <net/dst.h>
  45
  46#include <linux/io.h>
  47#include <asm/ccwdev.h>
  48#include <asm/ccwgroup.h>
  49#include <linux/uaccess.h>
  50
  51#include <asm/idals.h>
  52
  53#include "ctcm_fsms.h"
  54#include "ctcm_main.h"
  55
  56/* Some common global variables */
  57
  58/**
  59 * The root device for ctcm group devices
  60 */
  61static struct device *ctcm_root_dev;
  62
  63/*
  64 * Linked list of all detected channels.
  65 */
  66struct channel *channels;
  67
  68/**
  69 * Unpack a just received skb and hand it over to
  70 * upper layers.
  71 *
  72 *  ch		The channel where this skb has been received.
  73 *  pskb	The received skb.
  74 */
  75void ctcm_unpack_skb(struct channel *ch, struct sk_buff *pskb)
  76{
  77	struct net_device *dev = ch->netdev;
  78	struct ctcm_priv *priv = dev->ml_priv;
  79	__u16 len = *((__u16 *) pskb->data);
  80
  81	skb_put(pskb, 2 + LL_HEADER_LENGTH);
  82	skb_pull(pskb, 2);
  83	pskb->dev = dev;
  84	pskb->ip_summed = CHECKSUM_UNNECESSARY;
  85	while (len > 0) {
  86		struct sk_buff *skb;
  87		int skblen;
  88		struct ll_header *header = (struct ll_header *)pskb->data;
  89
  90		skb_pull(pskb, LL_HEADER_LENGTH);
  91		if ((ch->protocol == CTCM_PROTO_S390) &&
  92		    (header->type != ETH_P_IP)) {
  93			if (!(ch->logflags & LOG_FLAG_ILLEGALPKT)) {
  94				ch->logflags |= LOG_FLAG_ILLEGALPKT;
  95				/*
  96				 * Check packet type only if we stick strictly
  97				 * to S/390's protocol of OS390. This only
  98				 * supports IP. Otherwise allow any packet
  99				 * type.
 100				 */
 101				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 102					"%s(%s): Illegal packet type 0x%04x"
 103					" - dropping",
 104					CTCM_FUNTAIL, dev->name, header->type);
 105			}
 106			priv->stats.rx_dropped++;
 107			priv->stats.rx_frame_errors++;
 108			return;
 109		}
 110		pskb->protocol = cpu_to_be16(header->type);
 111		if ((header->length <= LL_HEADER_LENGTH) ||
 112		    (len <= LL_HEADER_LENGTH)) {
 113			if (!(ch->logflags & LOG_FLAG_ILLEGALSIZE)) {
 114				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 115					"%s(%s): Illegal packet size %d(%d,%d)"
 116					"- dropping",
 117					CTCM_FUNTAIL, dev->name,
 118					header->length, dev->mtu, len);
 119				ch->logflags |= LOG_FLAG_ILLEGALSIZE;
 120			}
 121
 122			priv->stats.rx_dropped++;
 123			priv->stats.rx_length_errors++;
 124			return;
 125		}
 126		header->length -= LL_HEADER_LENGTH;
 127		len -= LL_HEADER_LENGTH;
 128		if ((header->length > skb_tailroom(pskb)) ||
 129		    (header->length > len)) {
 130			if (!(ch->logflags & LOG_FLAG_OVERRUN)) {
 131				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 132					"%s(%s): Packet size %d (overrun)"
 133					" - dropping", CTCM_FUNTAIL,
 134						dev->name, header->length);
 135				ch->logflags |= LOG_FLAG_OVERRUN;
 136			}
 137
 138			priv->stats.rx_dropped++;
 139			priv->stats.rx_length_errors++;
 140			return;
 141		}
 142		skb_put(pskb, header->length);
 143		skb_reset_mac_header(pskb);
 144		len -= header->length;
 145		skb = dev_alloc_skb(pskb->len);
 146		if (!skb) {
 147			if (!(ch->logflags & LOG_FLAG_NOMEM)) {
 148				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 149					"%s(%s): MEMORY allocation error",
 150						CTCM_FUNTAIL, dev->name);
 151				ch->logflags |= LOG_FLAG_NOMEM;
 152			}
 153			priv->stats.rx_dropped++;
 154			return;
 155		}
 156		skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
 157					  pskb->len);
 158		skb_reset_mac_header(skb);
 159		skb->dev = pskb->dev;
 160		skb->protocol = pskb->protocol;
 161		pskb->ip_summed = CHECKSUM_UNNECESSARY;
 162		skblen = skb->len;
 163		/*
 164		 * reset logflags
 165		 */
 166		ch->logflags = 0;
 167		priv->stats.rx_packets++;
 168		priv->stats.rx_bytes += skblen;
 169		netif_rx_ni(skb);
 170		if (len > 0) {
 171			skb_pull(pskb, header->length);
 172			if (skb_tailroom(pskb) < LL_HEADER_LENGTH) {
 173				CTCM_DBF_DEV_NAME(TRACE, dev,
 174					"Overrun in ctcm_unpack_skb");
 175				ch->logflags |= LOG_FLAG_OVERRUN;
 176				return;
 177			}
 178			skb_put(pskb, LL_HEADER_LENGTH);
 179		}
 180	}
 181}
 182
 183/**
 184 * Release a specific channel in the channel list.
 185 *
 186 *  ch		Pointer to channel struct to be released.
 187 */
 188static void channel_free(struct channel *ch)
 189{
 190	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s)", CTCM_FUNTAIL, ch->id);
 191	ch->flags &= ~CHANNEL_FLAGS_INUSE;
 192	fsm_newstate(ch->fsm, CTC_STATE_IDLE);
 193}
 194
 195/**
 196 * Remove a specific channel in the channel list.
 197 *
 198 *  ch		Pointer to channel struct to be released.
 199 */
 200static void channel_remove(struct channel *ch)
 201{
 202	struct channel **c = &channels;
 203	char chid[CTCM_ID_SIZE+1];
 204	int ok = 0;
 205
 206	if (ch == NULL)
 207		return;
 208	else
 209		strncpy(chid, ch->id, CTCM_ID_SIZE);
 210
 211	channel_free(ch);
 212	while (*c) {
 213		if (*c == ch) {
 214			*c = ch->next;
 215			fsm_deltimer(&ch->timer);
 216			if (IS_MPC(ch))
 217				fsm_deltimer(&ch->sweep_timer);
 218
 219			kfree_fsm(ch->fsm);
 220			clear_normalized_cda(&ch->ccw[4]);
 221			if (ch->trans_skb != NULL) {
 222				clear_normalized_cda(&ch->ccw[1]);
 223				dev_kfree_skb_any(ch->trans_skb);
 224			}
 225			if (IS_MPC(ch)) {
 226				tasklet_kill(&ch->ch_tasklet);
 227				tasklet_kill(&ch->ch_disc_tasklet);
 228				kfree(ch->discontact_th);
 229			}
 230			kfree(ch->ccw);
 231			kfree(ch->irb);
 232			kfree(ch);
 233			ok = 1;
 234			break;
 235		}
 236		c = &((*c)->next);
 237	}
 238
 239	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s) %s", CTCM_FUNTAIL,
 240			chid, ok ? "OK" : "failed");
 241}
 242
 243/**
 244 * Get a specific channel from the channel list.
 245 *
 246 *  type	Type of channel we are interested in.
 247 *  id		Id of channel we are interested in.
 248 *  direction	Direction we want to use this channel for.
 249 *
 250 * returns Pointer to a channel or NULL if no matching channel available.
 251 */
 252static struct channel *channel_get(enum ctcm_channel_types type,
 253					char *id, int direction)
 254{
 255	struct channel *ch = channels;
 256
 257	while (ch && (strncmp(ch->id, id, CTCM_ID_SIZE) || (ch->type != type)))
 258		ch = ch->next;
 259	if (!ch) {
 260		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 261				"%s(%d, %s, %d) not found in channel list\n",
 262				CTCM_FUNTAIL, type, id, direction);
 263	} else {
 264		if (ch->flags & CHANNEL_FLAGS_INUSE)
 265			ch = NULL;
 266		else {
 267			ch->flags |= CHANNEL_FLAGS_INUSE;
 268			ch->flags &= ~CHANNEL_FLAGS_RWMASK;
 269			ch->flags |= (direction == CTCM_WRITE)
 270			    ? CHANNEL_FLAGS_WRITE : CHANNEL_FLAGS_READ;
 271			fsm_newstate(ch->fsm, CTC_STATE_STOPPED);
 272		}
 273	}
 274	return ch;
 275}
 276
 277static long ctcm_check_irb_error(struct ccw_device *cdev, struct irb *irb)
 278{
 279	if (!IS_ERR(irb))
 280		return 0;
 281
 282	CTCM_DBF_TEXT_(ERROR, CTC_DBF_WARN,
 283			"irb error %ld on device %s\n",
 284				PTR_ERR(irb), dev_name(&cdev->dev));
 285
 286	switch (PTR_ERR(irb)) {
 287	case -EIO:
 288		dev_err(&cdev->dev,
 289			"An I/O-error occurred on the CTCM device\n");
 290		break;
 291	case -ETIMEDOUT:
 292		dev_err(&cdev->dev,
 293			"An adapter hardware operation timed out\n");
 294		break;
 295	default:
 296		dev_err(&cdev->dev,
 297			"An error occurred on the adapter hardware\n");
 298	}
 299	return PTR_ERR(irb);
 300}
 301
 302
 303/**
 304 * Check sense of a unit check.
 305 *
 306 *  ch		The channel, the sense code belongs to.
 307 *  sense	The sense code to inspect.
 308 */
 309static void ccw_unit_check(struct channel *ch, __u8 sense)
 310{
 311	CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
 312			"%s(%s): %02x",
 313				CTCM_FUNTAIL, ch->id, sense);
 314
 315	if (sense & SNS0_INTERVENTION_REQ) {
 316		if (sense & 0x01) {
 317			if (ch->sense_rc != 0x01) {
 318				pr_notice(
 319					"%s: The communication peer has "
 320					"disconnected\n", ch->id);
 321				ch->sense_rc = 0x01;
 322			}
 323			fsm_event(ch->fsm, CTC_EVENT_UC_RCRESET, ch);
 324		} else {
 325			if (ch->sense_rc != SNS0_INTERVENTION_REQ) {
 326				pr_notice(
 327					"%s: The remote operating system is "
 328					"not available\n", ch->id);
 329				ch->sense_rc = SNS0_INTERVENTION_REQ;
 330			}
 331			fsm_event(ch->fsm, CTC_EVENT_UC_RSRESET, ch);
 332		}
 333	} else if (sense & SNS0_EQUIPMENT_CHECK) {
 334		if (sense & SNS0_BUS_OUT_CHECK) {
 335			if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 336				CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 337					"%s(%s): remote HW error %02x",
 338						CTCM_FUNTAIL, ch->id, sense);
 339				ch->sense_rc = SNS0_BUS_OUT_CHECK;
 340			}
 341			fsm_event(ch->fsm, CTC_EVENT_UC_HWFAIL, ch);
 342		} else {
 343			if (ch->sense_rc != SNS0_EQUIPMENT_CHECK) {
 344				CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 345					"%s(%s): remote read parity error %02x",
 346						CTCM_FUNTAIL, ch->id, sense);
 347				ch->sense_rc = SNS0_EQUIPMENT_CHECK;
 348			}
 349			fsm_event(ch->fsm, CTC_EVENT_UC_RXPARITY, ch);
 350		}
 351	} else if (sense & SNS0_BUS_OUT_CHECK) {
 352		if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 353			CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 354				"%s(%s): BUS OUT error %02x",
 355					CTCM_FUNTAIL, ch->id, sense);
 356			ch->sense_rc = SNS0_BUS_OUT_CHECK;
 357		}
 358		if (sense & 0x04)	/* data-streaming timeout */
 359			fsm_event(ch->fsm, CTC_EVENT_UC_TXTIMEOUT, ch);
 360		else			/* Data-transfer parity error */
 361			fsm_event(ch->fsm, CTC_EVENT_UC_TXPARITY, ch);
 362	} else if (sense & SNS0_CMD_REJECT) {
 363		if (ch->sense_rc != SNS0_CMD_REJECT) {
 364			CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 365				"%s(%s): Command rejected",
 366						CTCM_FUNTAIL, ch->id);
 367			ch->sense_rc = SNS0_CMD_REJECT;
 368		}
 369	} else if (sense == 0) {
 370		CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 371			"%s(%s): Unit check ZERO",
 372					CTCM_FUNTAIL, ch->id);
 373		fsm_event(ch->fsm, CTC_EVENT_UC_ZERO, ch);
 374	} else {
 375		CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 376			"%s(%s): Unit check code %02x unknown",
 377					CTCM_FUNTAIL, ch->id, sense);
 378		fsm_event(ch->fsm, CTC_EVENT_UC_UNKNOWN, ch);
 379	}
 380}
 381
 382int ctcm_ch_alloc_buffer(struct channel *ch)
 383{
 384	clear_normalized_cda(&ch->ccw[1]);
 385	ch->trans_skb = __dev_alloc_skb(ch->max_bufsize, GFP_ATOMIC | GFP_DMA);
 386	if (ch->trans_skb == NULL) {
 387		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 388			"%s(%s): %s trans_skb allocation error",
 389			CTCM_FUNTAIL, ch->id,
 390			(CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ?
 391				"RX" : "TX");
 392		return -ENOMEM;
 393	}
 394
 395	ch->ccw[1].count = ch->max_bufsize;
 396	if (set_normalized_cda(&ch->ccw[1], ch->trans_skb->data)) {
 397		dev_kfree_skb(ch->trans_skb);
 398		ch->trans_skb = NULL;
 399		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 400			"%s(%s): %s set norm_cda failed",
 401			CTCM_FUNTAIL, ch->id,
 402			(CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ?
 403				"RX" : "TX");
 404		return -ENOMEM;
 405	}
 406
 407	ch->ccw[1].count = 0;
 408	ch->trans_skb_data = ch->trans_skb->data;
 409	ch->flags &= ~CHANNEL_FLAGS_BUFSIZE_CHANGED;
 410	return 0;
 411}
 412
 413/*
 414 * Interface API for upper network layers
 415 */
 416
 417/**
 418 * Open an interface.
 419 * Called from generic network layer when ifconfig up is run.
 420 *
 421 *  dev		Pointer to interface struct.
 422 *
 423 * returns 0 on success, -ERRNO on failure. (Never fails.)
 424 */
 425int ctcm_open(struct net_device *dev)
 426{
 427	struct ctcm_priv *priv = dev->ml_priv;
 428
 429	CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 430	if (!IS_MPC(priv))
 431		fsm_event(priv->fsm,	DEV_EVENT_START, dev);
 432	return 0;
 433}
 434
 435/**
 436 * Close an interface.
 437 * Called from generic network layer when ifconfig down is run.
 438 *
 439 *  dev		Pointer to interface struct.
 440 *
 441 * returns 0 on success, -ERRNO on failure. (Never fails.)
 442 */
 443int ctcm_close(struct net_device *dev)
 444{
 445	struct ctcm_priv *priv = dev->ml_priv;
 446
 447	CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 448	if (!IS_MPC(priv))
 449		fsm_event(priv->fsm, DEV_EVENT_STOP, dev);
 450	return 0;
 451}
 452
 453
 454/**
 455 * Transmit a packet.
 456 * This is a helper function for ctcm_tx().
 457 *
 458 *  ch		Channel to be used for sending.
 459 *  skb		Pointer to struct sk_buff of packet to send.
 460 *            The linklevel header has already been set up
 461 *            by ctcm_tx().
 462 *
 463 * returns 0 on success, -ERRNO on failure. (Never fails.)
 464 */
 465static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
 466{
 467	unsigned long saveflags;
 468	struct ll_header header;
 469	int rc = 0;
 470	__u16 block_len;
 471	int ccw_idx;
 472	struct sk_buff *nskb;
 473	unsigned long hi;
 474
 475	/* we need to acquire the lock for testing the state
 476	 * otherwise we can have an IRQ changing the state to
 477	 * TXIDLE after the test but before acquiring the lock.
 478	 */
 479	spin_lock_irqsave(&ch->collect_lock, saveflags);
 480	if (fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) {
 481		int l = skb->len + LL_HEADER_LENGTH;
 482
 483		if (ch->collect_len + l > ch->max_bufsize - 2) {
 484			spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 485			return -EBUSY;
 486		} else {
 487			refcount_inc(&skb->users);
 488			header.length = l;
 489			header.type = be16_to_cpu(skb->protocol);
 490			header.unused = 0;
 491			memcpy(skb_push(skb, LL_HEADER_LENGTH), &header,
 492			       LL_HEADER_LENGTH);
 493			skb_queue_tail(&ch->collect_queue, skb);
 494			ch->collect_len += l;
 495		}
 496		spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 497				goto done;
 498	}
 499	spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 500	/*
 501	 * Protect skb against beeing free'd by upper
 502	 * layers.
 503	 */
 504	refcount_inc(&skb->users);
 505	ch->prof.txlen += skb->len;
 506	header.length = skb->len + LL_HEADER_LENGTH;
 507	header.type = be16_to_cpu(skb->protocol);
 508	header.unused = 0;
 509	memcpy(skb_push(skb, LL_HEADER_LENGTH), &header, LL_HEADER_LENGTH);
 510	block_len = skb->len + 2;
 511	*((__u16 *)skb_push(skb, 2)) = block_len;
 512
 513	/*
 514	 * IDAL support in CTCM is broken, so we have to
 515	 * care about skb's above 2G ourselves.
 516	 */
 517	hi = ((unsigned long)skb_tail_pointer(skb) + LL_HEADER_LENGTH) >> 31;
 518	if (hi) {
 519		nskb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 520		if (!nskb) {
 521			refcount_dec(&skb->users);
 522			skb_pull(skb, LL_HEADER_LENGTH + 2);
 523			ctcm_clear_busy(ch->netdev);
 524			return -ENOMEM;
 525		} else {
 526			skb_put_data(nskb, skb->data, skb->len);
 527			refcount_inc(&nskb->users);
 528			refcount_dec(&skb->users);
 529			dev_kfree_skb_irq(skb);
 530			skb = nskb;
 531		}
 532	}
 533
 534	ch->ccw[4].count = block_len;
 535	if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 536		/*
 537		 * idal allocation failed, try via copying to
 538		 * trans_skb. trans_skb usually has a pre-allocated
 539		 * idal.
 540		 */
 541		if (ctcm_checkalloc_buffer(ch)) {
 542			/*
 543			 * Remove our header. It gets added
 544			 * again on retransmit.
 545			 */
 546			refcount_dec(&skb->users);
 547			skb_pull(skb, LL_HEADER_LENGTH + 2);
 548			ctcm_clear_busy(ch->netdev);
 549			return -ENOMEM;
 550		}
 551
 552		skb_reset_tail_pointer(ch->trans_skb);
 553		ch->trans_skb->len = 0;
 554		ch->ccw[1].count = skb->len;
 555		skb_copy_from_linear_data(skb,
 556				skb_put(ch->trans_skb, skb->len), skb->len);
 557		refcount_dec(&skb->users);
 558		dev_kfree_skb_irq(skb);
 559		ccw_idx = 0;
 560	} else {
 561		skb_queue_tail(&ch->io_queue, skb);
 562		ccw_idx = 3;
 563	}
 564	if (do_debug_ccw)
 565		ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
 566					sizeof(struct ccw1) * 3);
 567	ch->retry = 0;
 568	fsm_newstate(ch->fsm, CTC_STATE_TX);
 569	fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 570	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 571	ch->prof.send_stamp = jiffies;
 572	rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx], 0, 0xff, 0);
 573	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 574	if (ccw_idx == 3)
 575		ch->prof.doios_single++;
 576	if (rc != 0) {
 577		fsm_deltimer(&ch->timer);
 578		ctcm_ccw_check_rc(ch, rc, "single skb TX");
 579		if (ccw_idx == 3)
 580			skb_dequeue_tail(&ch->io_queue);
 581		/*
 582		 * Remove our header. It gets added
 583		 * again on retransmit.
 584		 */
 585		skb_pull(skb, LL_HEADER_LENGTH + 2);
 586	} else if (ccw_idx == 0) {
 587		struct net_device *dev = ch->netdev;
 588		struct ctcm_priv *priv = dev->ml_priv;
 589		priv->stats.tx_packets++;
 590		priv->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
 591	}
 592done:
 593	ctcm_clear_busy(ch->netdev);
 594	return rc;
 595}
 596
 597static void ctcmpc_send_sweep_req(struct channel *rch)
 598{
 599	struct net_device *dev = rch->netdev;
 600	struct ctcm_priv *priv;
 601	struct mpc_group *grp;
 602	struct th_sweep *header;
 603	struct sk_buff *sweep_skb;
 604	struct channel *ch;
 605	/* int rc = 0; */
 606
 607	priv = dev->ml_priv;
 608	grp = priv->mpcg;
 609	ch = priv->channel[CTCM_WRITE];
 610
 611	/* sweep processing is not complete until response and request */
 612	/* has completed for all read channels in group		       */
 613	if (grp->in_sweep == 0) {
 614		grp->in_sweep = 1;
 615		grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
 616		grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
 617	}
 618
 619	sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
 620
 621	if (sweep_skb == NULL)	{
 622		/* rc = -ENOMEM; */
 623				goto nomem;
 624	}
 625
 626	header = kmalloc(TH_SWEEP_LENGTH, gfp_type());
 627
 628	if (!header) {
 629		dev_kfree_skb_any(sweep_skb);
 630		/* rc = -ENOMEM; */
 631				goto nomem;
 632	}
 633
 634	header->th.th_seg	= 0x00 ;
 635	header->th.th_ch_flag	= TH_SWEEP_REQ;  /* 0x0f */
 636	header->th.th_blk_flag	= 0x00;
 637	header->th.th_is_xid	= 0x00;
 638	header->th.th_seq_num	= 0x00;
 639	header->sw.th_last_seq	= ch->th_seq_num;
 640
 641	skb_put_data(sweep_skb, header, TH_SWEEP_LENGTH);
 642
 643	kfree(header);
 644
 645	netif_trans_update(dev);
 646	skb_queue_tail(&ch->sweep_queue, sweep_skb);
 647
 648	fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
 649
 650	return;
 651
 652nomem:
 653	grp->in_sweep = 0;
 654	ctcm_clear_busy(dev);
 655	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 656
 657	return;
 658}
 659
 660/*
 661 * MPC mode version of transmit_skb
 662 */
 663static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
 664{
 665	struct pdu *p_header;
 666	struct net_device *dev = ch->netdev;
 667	struct ctcm_priv *priv = dev->ml_priv;
 668	struct mpc_group *grp = priv->mpcg;
 669	struct th_header *header;
 670	struct sk_buff *nskb;
 671	int rc = 0;
 672	int ccw_idx;
 673	unsigned long hi;
 674	unsigned long saveflags = 0;	/* avoids compiler warning */
 675
 676	CTCM_PR_DEBUG("Enter %s: %s, cp=%i ch=0x%p id=%s state=%s\n",
 677			__func__, dev->name, smp_processor_id(), ch,
 678					ch->id, fsm_getstate_str(ch->fsm));
 679
 680	if ((fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) || grp->in_sweep) {
 681		spin_lock_irqsave(&ch->collect_lock, saveflags);
 682		refcount_inc(&skb->users);
 683		p_header = kmalloc(PDU_HEADER_LENGTH, gfp_type());
 684
 685		if (!p_header) {
 686			spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 687				goto nomem_exit;
 688		}
 689
 690		p_header->pdu_offset = skb->len;
 
 691		p_header->pdu_proto = 0x01;
 692		p_header->pdu_flag = 0x00;
 693		if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
 694			p_header->pdu_flag |= PDU_FIRST | PDU_CNTL;
 695		} else {
 696			p_header->pdu_flag |= PDU_FIRST;
 697		}
 698		p_header->pdu_seq = 0;
 699		memcpy(skb_push(skb, PDU_HEADER_LENGTH), p_header,
 700		       PDU_HEADER_LENGTH);
 701
 702		CTCM_PR_DEBUG("%s(%s): Put on collect_q - skb len: %04x \n"
 703				"pdu header and data for up to 32 bytes:\n",
 704				__func__, dev->name, skb->len);
 705		CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 706
 707		skb_queue_tail(&ch->collect_queue, skb);
 708		ch->collect_len += skb->len;
 709		kfree(p_header);
 710
 711		spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 712			goto done;
 713	}
 714
 715	/*
 716	 * Protect skb against beeing free'd by upper
 717	 * layers.
 718	 */
 719	refcount_inc(&skb->users);
 720
 721	/*
 722	 * IDAL support in CTCM is broken, so we have to
 723	 * care about skb's above 2G ourselves.
 724	 */
 725	hi = ((unsigned long)skb->tail + TH_HEADER_LENGTH) >> 31;
 726	if (hi) {
 727		nskb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 728		if (!nskb) {
 729			goto nomem_exit;
 730		} else {
 731			skb_put_data(nskb, skb->data, skb->len);
 732			refcount_inc(&nskb->users);
 733			refcount_dec(&skb->users);
 734			dev_kfree_skb_irq(skb);
 735			skb = nskb;
 736		}
 737	}
 738
 739	p_header = kmalloc(PDU_HEADER_LENGTH, gfp_type());
 740
 741	if (!p_header)
 742		goto nomem_exit;
 743
 744	p_header->pdu_offset = skb->len;
 745	p_header->pdu_proto = 0x01;
 746	p_header->pdu_flag = 0x00;
 747	p_header->pdu_seq = 0;
 748	if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
 749		p_header->pdu_flag |= PDU_FIRST | PDU_CNTL;
 750	} else {
 751		p_header->pdu_flag |= PDU_FIRST;
 752	}
 753	memcpy(skb_push(skb, PDU_HEADER_LENGTH), p_header, PDU_HEADER_LENGTH);
 754
 755	kfree(p_header);
 756
 757	if (ch->collect_len > 0) {
 758		spin_lock_irqsave(&ch->collect_lock, saveflags);
 759		skb_queue_tail(&ch->collect_queue, skb);
 760		ch->collect_len += skb->len;
 761		skb = skb_dequeue(&ch->collect_queue);
 762		ch->collect_len -= skb->len;
 763		spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 764	}
 765
 766	p_header = (struct pdu *)skb->data;
 767	p_header->pdu_flag |= PDU_LAST;
 768
 769	ch->prof.txlen += skb->len - PDU_HEADER_LENGTH;
 770
 771	header = kmalloc(TH_HEADER_LENGTH, gfp_type());
 772	if (!header)
 773		goto nomem_exit;
 774
 775	header->th_seg = 0x00;
 776	header->th_ch_flag = TH_HAS_PDU;  /* Normal data */
 777	header->th_blk_flag = 0x00;
 778	header->th_is_xid = 0x00;          /* Just data here */
 779	ch->th_seq_num++;
 780	header->th_seq_num = ch->th_seq_num;
 781
 782	CTCM_PR_DBGDATA("%s(%s) ToVTAM_th_seq= %08x\n" ,
 783		       __func__, dev->name, ch->th_seq_num);
 784
 785	/* put the TH on the packet */
 786	memcpy(skb_push(skb, TH_HEADER_LENGTH), header, TH_HEADER_LENGTH);
 787
 788	kfree(header);
 789
 790	CTCM_PR_DBGDATA("%s(%s): skb len: %04x\n - pdu header and data for "
 791			"up to 32 bytes sent to vtam:\n",
 792				__func__, dev->name, skb->len);
 793	CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 794
 795	ch->ccw[4].count = skb->len;
 796	if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 797		/*
 798		 * idal allocation failed, try via copying to trans_skb.
 799		 * trans_skb usually has a pre-allocated idal.
 800		 */
 801		if (ctcm_checkalloc_buffer(ch)) {
 802			/*
 803			 * Remove our header.
 804			 * It gets added again on retransmit.
 805			 */
 806				goto nomem_exit;
 807		}
 808
 809		skb_reset_tail_pointer(ch->trans_skb);
 810		ch->trans_skb->len = 0;
 811		ch->ccw[1].count = skb->len;
 812		skb_put_data(ch->trans_skb, skb->data, skb->len);
 813		refcount_dec(&skb->users);
 814		dev_kfree_skb_irq(skb);
 815		ccw_idx = 0;
 816		CTCM_PR_DBGDATA("%s(%s): trans_skb len: %04x\n"
 817				"up to 32 bytes sent to vtam:\n",
 818				__func__, dev->name, ch->trans_skb->len);
 819		CTCM_D3_DUMP((char *)ch->trans_skb->data,
 820				min_t(int, 32, ch->trans_skb->len));
 821	} else {
 822		skb_queue_tail(&ch->io_queue, skb);
 823		ccw_idx = 3;
 824	}
 825	ch->retry = 0;
 826	fsm_newstate(ch->fsm, CTC_STATE_TX);
 827	fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 828
 829	if (do_debug_ccw)
 830		ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
 831					sizeof(struct ccw1) * 3);
 832
 833	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 834	ch->prof.send_stamp = jiffies;
 835	rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx], 0, 0xff, 0);
 836	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 837	if (ccw_idx == 3)
 838		ch->prof.doios_single++;
 839	if (rc != 0) {
 840		fsm_deltimer(&ch->timer);
 841		ctcm_ccw_check_rc(ch, rc, "single skb TX");
 842		if (ccw_idx == 3)
 843			skb_dequeue_tail(&ch->io_queue);
 844	} else if (ccw_idx == 0) {
 845		priv->stats.tx_packets++;
 846		priv->stats.tx_bytes += skb->len - TH_HEADER_LENGTH;
 847	}
 848	if (ch->th_seq_num > 0xf0000000)	/* Chose at random. */
 849		ctcmpc_send_sweep_req(ch);
 850
 851	goto done;
 852nomem_exit:
 853	CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_CRIT,
 854			"%s(%s): MEMORY allocation ERROR\n",
 855			CTCM_FUNTAIL, ch->id);
 856	rc = -ENOMEM;
 857	refcount_dec(&skb->users);
 858	dev_kfree_skb_any(skb);
 859	fsm_event(priv->mpcg->fsm, MPCG_EVENT_INOP, dev);
 860done:
 861	CTCM_PR_DEBUG("Exit %s(%s)\n", __func__, dev->name);
 862	return rc;
 863}
 864
 865/**
 866 * Start transmission of a packet.
 867 * Called from generic network device layer.
 868 *
 869 *  skb		Pointer to buffer containing the packet.
 870 *  dev		Pointer to interface struct.
 871 *
 872 * returns 0 if packet consumed, !0 if packet rejected.
 873 *         Note: If we return !0, then the packet is free'd by
 874 *               the generic network layer.
 875 */
 876/* first merge version - leaving both functions separated */
 877static int ctcm_tx(struct sk_buff *skb, struct net_device *dev)
 878{
 879	struct ctcm_priv *priv = dev->ml_priv;
 880
 881	if (skb == NULL) {
 882		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 883				"%s(%s): NULL sk_buff passed",
 884					CTCM_FUNTAIL, dev->name);
 885		priv->stats.tx_dropped++;
 886		return NETDEV_TX_OK;
 887	}
 888	if (skb_headroom(skb) < (LL_HEADER_LENGTH + 2)) {
 889		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 890			"%s(%s): Got sk_buff with head room < %ld bytes",
 891			CTCM_FUNTAIL, dev->name, LL_HEADER_LENGTH + 2);
 892		dev_kfree_skb(skb);
 893		priv->stats.tx_dropped++;
 894		return NETDEV_TX_OK;
 895	}
 896
 897	/*
 898	 * If channels are not running, try to restart them
 899	 * and throw away packet.
 900	 */
 901	if (fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) {
 902		fsm_event(priv->fsm, DEV_EVENT_START, dev);
 903		dev_kfree_skb(skb);
 904		priv->stats.tx_dropped++;
 905		priv->stats.tx_errors++;
 906		priv->stats.tx_carrier_errors++;
 907		return NETDEV_TX_OK;
 908	}
 909
 910	if (ctcm_test_and_set_busy(dev))
 911		return NETDEV_TX_BUSY;
 912
 913	netif_trans_update(dev);
 914	if (ctcm_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0)
 915		return NETDEV_TX_BUSY;
 916	return NETDEV_TX_OK;
 917}
 918
 919/* unmerged MPC variant of ctcm_tx */
 920static int ctcmpc_tx(struct sk_buff *skb, struct net_device *dev)
 921{
 922	int len = 0;
 923	struct ctcm_priv *priv = dev->ml_priv;
 924	struct mpc_group *grp  = priv->mpcg;
 925	struct sk_buff *newskb = NULL;
 926
 927	/*
 928	 * Some sanity checks ...
 929	 */
 930	if (skb == NULL) {
 931		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 932			"%s(%s): NULL sk_buff passed",
 933					CTCM_FUNTAIL, dev->name);
 934		priv->stats.tx_dropped++;
 935					goto done;
 936	}
 937	if (skb_headroom(skb) < (TH_HEADER_LENGTH + PDU_HEADER_LENGTH)) {
 938		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 939			"%s(%s): Got sk_buff with head room < %ld bytes",
 940			CTCM_FUNTAIL, dev->name,
 941				TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 942
 943		CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 944
 945		len =  skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
 946		newskb = __dev_alloc_skb(len, gfp_type() | GFP_DMA);
 947
 948		if (!newskb) {
 949			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 950				"%s: %s: __dev_alloc_skb failed",
 951						__func__, dev->name);
 952
 953			dev_kfree_skb_any(skb);
 954			priv->stats.tx_dropped++;
 955			priv->stats.tx_errors++;
 956			priv->stats.tx_carrier_errors++;
 957			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 958					goto done;
 959		}
 960		newskb->protocol = skb->protocol;
 961		skb_reserve(newskb, TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 962		skb_put_data(newskb, skb->data, skb->len);
 963		dev_kfree_skb_any(skb);
 964		skb = newskb;
 965	}
 966
 967	/*
 968	 * If channels are not running,
 969	 * notify anybody about a link failure and throw
 970	 * away packet.
 971	 */
 972	if ((fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) ||
 973	   (fsm_getstate(grp->fsm) <  MPCG_STATE_XID2INITW)) {
 974		dev_kfree_skb_any(skb);
 975		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 976			"%s(%s): inactive MPCGROUP - dropped",
 977					CTCM_FUNTAIL, dev->name);
 978		priv->stats.tx_dropped++;
 979		priv->stats.tx_errors++;
 980		priv->stats.tx_carrier_errors++;
 981					goto done;
 982	}
 983
 984	if (ctcm_test_and_set_busy(dev)) {
 985		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 986			"%s(%s): device busy - dropped",
 987					CTCM_FUNTAIL, dev->name);
 988		dev_kfree_skb_any(skb);
 989		priv->stats.tx_dropped++;
 990		priv->stats.tx_errors++;
 991		priv->stats.tx_carrier_errors++;
 992		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 993					goto done;
 994	}
 995
 996	netif_trans_update(dev);
 997	if (ctcmpc_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0) {
 998		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 999			"%s(%s): device error - dropped",
1000					CTCM_FUNTAIL, dev->name);
1001		dev_kfree_skb_any(skb);
1002		priv->stats.tx_dropped++;
1003		priv->stats.tx_errors++;
1004		priv->stats.tx_carrier_errors++;
1005		ctcm_clear_busy(dev);
1006		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1007					goto done;
1008	}
1009	ctcm_clear_busy(dev);
1010done:
1011	if (do_debug)
1012		MPC_DBF_DEV_NAME(TRACE, dev, "exit");
1013
1014	return NETDEV_TX_OK;	/* handle freeing of skb here */
1015}
1016
1017
1018/**
1019 * Sets MTU of an interface.
1020 *
1021 *  dev		Pointer to interface struct.
1022 *  new_mtu	The new MTU to use for this interface.
1023 *
1024 * returns 0 on success, -EINVAL if MTU is out of valid range.
1025 *         (valid range is 576 .. 65527). If VM is on the
1026 *         remote side, maximum MTU is 32760, however this is
1027 *         not checked here.
1028 */
1029static int ctcm_change_mtu(struct net_device *dev, int new_mtu)
1030{
1031	struct ctcm_priv *priv;
1032	int max_bufsize;
1033
1034	priv = dev->ml_priv;
1035	max_bufsize = priv->channel[CTCM_READ]->max_bufsize;
1036
1037	if (IS_MPC(priv)) {
1038		if (new_mtu > max_bufsize - TH_HEADER_LENGTH)
1039			return -EINVAL;
1040		dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1041	} else {
1042		if (new_mtu > max_bufsize - LL_HEADER_LENGTH - 2)
1043			return -EINVAL;
1044		dev->hard_header_len = LL_HEADER_LENGTH + 2;
1045	}
1046	dev->mtu = new_mtu;
1047	return 0;
1048}
1049
1050/**
1051 * Returns interface statistics of a device.
1052 *
1053 *  dev		Pointer to interface struct.
1054 *
1055 * returns Pointer to stats struct of this interface.
1056 */
1057static struct net_device_stats *ctcm_stats(struct net_device *dev)
1058{
1059	return &((struct ctcm_priv *)dev->ml_priv)->stats;
1060}
1061
1062static void ctcm_free_netdevice(struct net_device *dev)
1063{
1064	struct ctcm_priv *priv;
1065	struct mpc_group *grp;
1066
1067	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1068			"%s(%s)", CTCM_FUNTAIL, dev->name);
1069	priv = dev->ml_priv;
1070	if (priv) {
1071		grp = priv->mpcg;
1072		if (grp) {
1073			if (grp->fsm)
1074				kfree_fsm(grp->fsm);
1075			dev_kfree_skb(grp->xid_skb);
1076			dev_kfree_skb(grp->rcvd_xid_skb);
1077			tasklet_kill(&grp->mpc_tasklet2);
1078			kfree(grp);
1079			priv->mpcg = NULL;
1080		}
1081		if (priv->fsm) {
1082			kfree_fsm(priv->fsm);
1083			priv->fsm = NULL;
1084		}
1085		kfree(priv->xid);
1086		priv->xid = NULL;
1087	/*
1088	 * Note: kfree(priv); is done in "opposite" function of
1089	 * allocator function probe_device which is remove_device.
1090	 */
1091	}
1092#ifdef MODULE
1093	free_netdev(dev);
1094#endif
1095}
1096
1097struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv);
1098
1099static const struct net_device_ops ctcm_netdev_ops = {
1100	.ndo_open		= ctcm_open,
1101	.ndo_stop		= ctcm_close,
1102	.ndo_get_stats		= ctcm_stats,
1103	.ndo_change_mtu	   	= ctcm_change_mtu,
1104	.ndo_start_xmit		= ctcm_tx,
1105};
1106
1107static const struct net_device_ops ctcm_mpc_netdev_ops = {
1108	.ndo_open		= ctcm_open,
1109	.ndo_stop		= ctcm_close,
1110	.ndo_get_stats		= ctcm_stats,
1111	.ndo_change_mtu	   	= ctcm_change_mtu,
1112	.ndo_start_xmit		= ctcmpc_tx,
1113};
1114
1115static void ctcm_dev_setup(struct net_device *dev)
1116{
1117	dev->type = ARPHRD_SLIP;
1118	dev->tx_queue_len = 100;
1119	dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1120	dev->min_mtu = 576;
1121	dev->max_mtu = 65527;
1122}
1123
1124/*
1125 * Initialize everything of the net device except the name and the
1126 * channel structs.
1127 */
1128static struct net_device *ctcm_init_netdevice(struct ctcm_priv *priv)
1129{
1130	struct net_device *dev;
1131	struct mpc_group *grp;
1132	if (!priv)
1133		return NULL;
1134
1135	if (IS_MPC(priv))
1136		dev = alloc_netdev(0, MPC_DEVICE_GENE, NET_NAME_UNKNOWN,
1137				   ctcm_dev_setup);
1138	else
1139		dev = alloc_netdev(0, CTC_DEVICE_GENE, NET_NAME_UNKNOWN,
1140				   ctcm_dev_setup);
1141
1142	if (!dev) {
1143		CTCM_DBF_TEXT_(ERROR, CTC_DBF_CRIT,
1144			"%s: MEMORY allocation ERROR",
1145			CTCM_FUNTAIL);
1146		return NULL;
1147	}
1148	dev->ml_priv = priv;
1149	priv->fsm = init_fsm("ctcmdev", dev_state_names, dev_event_names,
1150				CTCM_NR_DEV_STATES, CTCM_NR_DEV_EVENTS,
1151				dev_fsm, dev_fsm_len, GFP_KERNEL);
1152	if (priv->fsm == NULL) {
1153		CTCMY_DBF_DEV(SETUP, dev, "init_fsm error");
1154		free_netdev(dev);
1155		return NULL;
1156	}
1157	fsm_newstate(priv->fsm, DEV_STATE_STOPPED);
1158	fsm_settimer(priv->fsm, &priv->restart_timer);
1159
1160	if (IS_MPC(priv)) {
1161		/*  MPC Group Initializations  */
1162		grp = ctcmpc_init_mpc_group(priv);
1163		if (grp == NULL) {
1164			MPC_DBF_DEV(SETUP, dev, "init_mpc_group error");
1165			free_netdev(dev);
1166			return NULL;
1167		}
1168		tasklet_init(&grp->mpc_tasklet2,
1169				mpc_group_ready, (unsigned long)dev);
1170		dev->mtu = MPC_BUFSIZE_DEFAULT -
1171				TH_HEADER_LENGTH - PDU_HEADER_LENGTH;
1172
1173		dev->netdev_ops = &ctcm_mpc_netdev_ops;
1174		dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1175		priv->buffer_size = MPC_BUFSIZE_DEFAULT;
1176	} else {
1177		dev->mtu = CTCM_BUFSIZE_DEFAULT - LL_HEADER_LENGTH - 2;
1178		dev->netdev_ops = &ctcm_netdev_ops;
1179		dev->hard_header_len = LL_HEADER_LENGTH + 2;
1180	}
1181
1182	CTCMY_DBF_DEV(SETUP, dev, "finished");
1183
1184	return dev;
1185}
1186
1187/**
1188 * Main IRQ handler.
1189 *
1190 *  cdev	The ccw_device the interrupt is for.
1191 *  intparm	interruption parameter.
1192 *  irb		interruption response block.
1193 */
1194static void ctcm_irq_handler(struct ccw_device *cdev,
1195				unsigned long intparm, struct irb *irb)
1196{
1197	struct channel		*ch;
1198	struct net_device	*dev;
1199	struct ctcm_priv	*priv;
1200	struct ccwgroup_device	*cgdev;
1201	int cstat;
1202	int dstat;
1203
1204	CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
1205		"Enter %s(%s)", CTCM_FUNTAIL, dev_name(&cdev->dev));
1206
1207	if (ctcm_check_irb_error(cdev, irb))
1208		return;
1209
1210	cgdev = dev_get_drvdata(&cdev->dev);
1211
1212	cstat = irb->scsw.cmd.cstat;
1213	dstat = irb->scsw.cmd.dstat;
1214
1215	/* Check for unsolicited interrupts. */
1216	if (cgdev == NULL) {
1217		CTCM_DBF_TEXT_(TRACE, CTC_DBF_ERROR,
1218			"%s(%s) unsolicited irq: c-%02x d-%02x\n",
1219			CTCM_FUNTAIL, dev_name(&cdev->dev), cstat, dstat);
1220		dev_warn(&cdev->dev,
1221			"The adapter received a non-specific IRQ\n");
1222		return;
1223	}
1224
1225	priv = dev_get_drvdata(&cgdev->dev);
1226
1227	/* Try to extract channel from driver data. */
1228	if (priv->channel[CTCM_READ]->cdev == cdev)
1229		ch = priv->channel[CTCM_READ];
1230	else if (priv->channel[CTCM_WRITE]->cdev == cdev)
1231		ch = priv->channel[CTCM_WRITE];
1232	else {
1233		dev_err(&cdev->dev,
1234			"%s: Internal error: Can't determine channel for "
1235			"interrupt device %s\n",
1236			__func__, dev_name(&cdev->dev));
1237			/* Explain: inconsistent internal structures */
1238		return;
1239	}
1240
1241	dev = ch->netdev;
1242	if (dev == NULL) {
1243		dev_err(&cdev->dev,
1244			"%s Internal error: net_device is NULL, ch = 0x%p\n",
1245			__func__, ch);
1246			/* Explain: inconsistent internal structures */
1247		return;
1248	}
1249
1250	/* Copy interruption response block. */
1251	memcpy(ch->irb, irb, sizeof(struct irb));
1252
1253	/* Issue error message and return on subchannel error code */
1254	if (irb->scsw.cmd.cstat) {
1255		fsm_event(ch->fsm, CTC_EVENT_SC_UNKNOWN, ch);
1256		CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1257			"%s(%s): sub-ch check %s: cs=%02x ds=%02x",
1258				CTCM_FUNTAIL, dev->name, ch->id, cstat, dstat);
1259		dev_warn(&cdev->dev,
1260				"A check occurred on the subchannel\n");
1261		return;
1262	}
1263
1264	/* Check the reason-code of a unit check */
1265	if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) {
1266		if ((irb->ecw[0] & ch->sense_rc) == 0)
1267			/* print it only once */
1268			CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1269				"%s(%s): sense=%02x, ds=%02x",
1270				CTCM_FUNTAIL, ch->id, irb->ecw[0], dstat);
1271		ccw_unit_check(ch, irb->ecw[0]);
1272		return;
1273	}
1274	if (irb->scsw.cmd.dstat & DEV_STAT_BUSY) {
1275		if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
1276			fsm_event(ch->fsm, CTC_EVENT_ATTNBUSY, ch);
1277		else
1278			fsm_event(ch->fsm, CTC_EVENT_BUSY, ch);
1279		return;
1280	}
1281	if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
1282		fsm_event(ch->fsm, CTC_EVENT_ATTN, ch);
1283		return;
1284	}
1285	if ((irb->scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS) ||
1286	    (irb->scsw.cmd.stctl == SCSW_STCTL_STATUS_PEND) ||
1287	    (irb->scsw.cmd.stctl ==
1288	     (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)))
1289		fsm_event(ch->fsm, CTC_EVENT_FINSTAT, ch);
1290	else
1291		fsm_event(ch->fsm, CTC_EVENT_IRQ, ch);
1292
1293}
1294
1295static const struct device_type ctcm_devtype = {
1296	.name = "ctcm",
1297	.groups = ctcm_attr_groups,
1298};
1299
1300/**
1301 * Add ctcm specific attributes.
1302 * Add ctcm private data.
1303 *
1304 *  cgdev	pointer to ccwgroup_device just added
1305 *
1306 * returns 0 on success, !0 on failure.
1307 */
1308static int ctcm_probe_device(struct ccwgroup_device *cgdev)
1309{
1310	struct ctcm_priv *priv;
1311
1312	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1313			"%s %p",
1314			__func__, cgdev);
1315
1316	if (!get_device(&cgdev->dev))
1317		return -ENODEV;
1318
1319	priv = kzalloc(sizeof(struct ctcm_priv), GFP_KERNEL);
1320	if (!priv) {
1321		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
1322			"%s: memory allocation failure",
1323			CTCM_FUNTAIL);
1324		put_device(&cgdev->dev);
1325		return -ENOMEM;
1326	}
1327	priv->buffer_size = CTCM_BUFSIZE_DEFAULT;
1328	cgdev->cdev[0]->handler = ctcm_irq_handler;
1329	cgdev->cdev[1]->handler = ctcm_irq_handler;
1330	dev_set_drvdata(&cgdev->dev, priv);
1331	cgdev->dev.type = &ctcm_devtype;
1332
1333	return 0;
1334}
1335
1336/**
1337 * Add a new channel to the list of channels.
1338 * Keeps the channel list sorted.
1339 *
1340 *  cdev	The ccw_device to be added.
1341 *  type	The type class of the new channel.
1342 *  priv	Points to the private data of the ccwgroup_device.
1343 *
1344 * returns 0 on success, !0 on error.
1345 */
1346static int add_channel(struct ccw_device *cdev, enum ctcm_channel_types type,
1347				struct ctcm_priv *priv)
1348{
1349	struct channel **c = &channels;
1350	struct channel *ch;
1351	int ccw_num;
1352	int rc = 0;
1353
1354	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1355		"%s(%s), type %d, proto %d",
1356			__func__, dev_name(&cdev->dev),	type, priv->protocol);
1357
1358	ch = kzalloc(sizeof(struct channel), GFP_KERNEL);
1359	if (ch == NULL)
1360		return -ENOMEM;
1361
1362	ch->protocol = priv->protocol;
1363	if (IS_MPC(priv)) {
1364		ch->discontact_th = kzalloc(TH_HEADER_LENGTH, gfp_type());
1365		if (ch->discontact_th == NULL)
1366					goto nomem_return;
1367
1368		ch->discontact_th->th_blk_flag = TH_DISCONTACT;
1369		tasklet_init(&ch->ch_disc_tasklet,
1370			mpc_action_send_discontact, (unsigned long)ch);
1371
1372		tasklet_init(&ch->ch_tasklet, ctcmpc_bh, (unsigned long)ch);
1373		ch->max_bufsize = (MPC_BUFSIZE_DEFAULT - 35);
1374		ccw_num = 17;
1375	} else
1376		ccw_num = 8;
1377
1378	ch->ccw = kcalloc(ccw_num, sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
1379	if (ch->ccw == NULL)
1380					goto nomem_return;
1381
1382	ch->cdev = cdev;
1383	snprintf(ch->id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev->dev));
1384	ch->type = type;
1385
1386	/**
1387	 * "static" ccws are used in the following way:
1388	 *
1389	 * ccw[0..2] (Channel program for generic I/O):
1390	 *           0: prepare
1391	 *           1: read or write (depending on direction) with fixed
1392	 *              buffer (idal allocated once when buffer is allocated)
1393	 *           2: nop
1394	 * ccw[3..5] (Channel program for direct write of packets)
1395	 *           3: prepare
1396	 *           4: write (idal allocated on every write).
1397	 *           5: nop
1398	 * ccw[6..7] (Channel program for initial channel setup):
1399	 *           6: set extended mode
1400	 *           7: nop
1401	 *
1402	 * ch->ccw[0..5] are initialized in ch_action_start because
1403	 * the channel's direction is yet unknown here.
1404	 *
1405	 * ccws used for xid2 negotiations
1406	 *  ch-ccw[8-14] need to be used for the XID exchange either
1407	 *    X side XID2 Processing
1408	 *       8:  write control
1409	 *       9:  write th
1410	 *	     10: write XID
1411	 *	     11: read th from secondary
1412	 *	     12: read XID   from secondary
1413	 *	     13: read 4 byte ID
1414	 *	     14: nop
1415	 *    Y side XID Processing
1416	 *	     8:  sense
1417	 *       9:  read th
1418	 *	     10: read XID
1419	 *	     11: write th
1420	 *	     12: write XID
1421	 *	     13: write 4 byte ID
1422	 *	     14: nop
1423	 *
1424	 *  ccws used for double noop due to VM timing issues
1425	 *  which result in unrecoverable Busy on channel
1426	 *       15: nop
1427	 *       16: nop
1428	 */
1429	ch->ccw[6].cmd_code	= CCW_CMD_SET_EXTENDED;
1430	ch->ccw[6].flags	= CCW_FLAG_SLI;
1431
1432	ch->ccw[7].cmd_code	= CCW_CMD_NOOP;
1433	ch->ccw[7].flags	= CCW_FLAG_SLI;
1434
1435	if (IS_MPC(priv)) {
1436		ch->ccw[15].cmd_code = CCW_CMD_WRITE;
1437		ch->ccw[15].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
1438		ch->ccw[15].count    = TH_HEADER_LENGTH;
1439		ch->ccw[15].cda      = virt_to_phys(ch->discontact_th);
1440
1441		ch->ccw[16].cmd_code = CCW_CMD_NOOP;
1442		ch->ccw[16].flags    = CCW_FLAG_SLI;
1443
1444		ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1445				ctc_ch_event_names, CTC_MPC_NR_STATES,
1446				CTC_MPC_NR_EVENTS, ctcmpc_ch_fsm,
1447				mpc_ch_fsm_len, GFP_KERNEL);
1448	} else {
1449		ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1450				ctc_ch_event_names, CTC_NR_STATES,
1451				CTC_NR_EVENTS, ch_fsm,
1452				ch_fsm_len, GFP_KERNEL);
1453	}
1454	if (ch->fsm == NULL)
1455				goto nomem_return;
1456
1457	fsm_newstate(ch->fsm, CTC_STATE_IDLE);
1458
1459	ch->irb = kzalloc(sizeof(struct irb), GFP_KERNEL);
1460	if (ch->irb == NULL)
1461				goto nomem_return;
1462
1463	while (*c && ctcm_less_than((*c)->id, ch->id))
1464		c = &(*c)->next;
1465
1466	if (*c && (!strncmp((*c)->id, ch->id, CTCM_ID_SIZE))) {
1467		CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1468				"%s (%s) already in list, using old entry",
1469				__func__, (*c)->id);
1470
1471				goto free_return;
1472	}
1473
1474	spin_lock_init(&ch->collect_lock);
1475
1476	fsm_settimer(ch->fsm, &ch->timer);
1477	skb_queue_head_init(&ch->io_queue);
1478	skb_queue_head_init(&ch->collect_queue);
1479
1480	if (IS_MPC(priv)) {
1481		fsm_settimer(ch->fsm, &ch->sweep_timer);
1482		skb_queue_head_init(&ch->sweep_queue);
1483	}
1484	ch->next = *c;
1485	*c = ch;
1486	return 0;
1487
1488nomem_return:
1489	rc = -ENOMEM;
1490
1491free_return:	/* note that all channel pointers are 0 or valid */
1492	kfree(ch->ccw);
1493	kfree(ch->discontact_th);
1494	kfree_fsm(ch->fsm);
1495	kfree(ch->irb);
1496	kfree(ch);
1497	return rc;
1498}
1499
1500/*
1501 * Return type of a detected device.
1502 */
1503static enum ctcm_channel_types get_channel_type(struct ccw_device_id *id)
1504{
1505	enum ctcm_channel_types type;
1506	type = (enum ctcm_channel_types)id->driver_info;
1507
1508	if (type == ctcm_channel_type_ficon)
1509		type = ctcm_channel_type_escon;
1510
1511	return type;
1512}
1513
1514/**
1515 *
1516 * Setup an interface.
1517 *
1518 *  cgdev	Device to be setup.
1519 *
1520 * returns 0 on success, !0 on failure.
1521 */
1522static int ctcm_new_device(struct ccwgroup_device *cgdev)
1523{
1524	char read_id[CTCM_ID_SIZE];
1525	char write_id[CTCM_ID_SIZE];
1526	int direction;
1527	enum ctcm_channel_types type;
1528	struct ctcm_priv *priv;
1529	struct net_device *dev;
1530	struct ccw_device *cdev0;
1531	struct ccw_device *cdev1;
1532	struct channel *readc;
1533	struct channel *writec;
1534	int ret;
1535	int result;
1536
1537	priv = dev_get_drvdata(&cgdev->dev);
1538	if (!priv) {
1539		result = -ENODEV;
1540		goto out_err_result;
1541	}
1542
1543	cdev0 = cgdev->cdev[0];
1544	cdev1 = cgdev->cdev[1];
1545
1546	type = get_channel_type(&cdev0->id);
1547
1548	snprintf(read_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev0->dev));
1549	snprintf(write_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev1->dev));
1550
1551	ret = add_channel(cdev0, type, priv);
1552	if (ret) {
1553		result = ret;
1554		goto out_err_result;
1555	}
1556	ret = add_channel(cdev1, type, priv);
1557	if (ret) {
1558		result = ret;
1559		goto out_remove_channel1;
1560	}
1561
1562	ret = ccw_device_set_online(cdev0);
1563	if (ret != 0) {
1564		CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1565			"%s(%s) set_online rc=%d",
1566				CTCM_FUNTAIL, read_id, ret);
1567		result = -EIO;
1568		goto out_remove_channel2;
1569	}
1570
1571	ret = ccw_device_set_online(cdev1);
1572	if (ret != 0) {
1573		CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1574			"%s(%s) set_online rc=%d",
1575				CTCM_FUNTAIL, write_id, ret);
1576
1577		result = -EIO;
1578		goto out_ccw1;
1579	}
1580
1581	dev = ctcm_init_netdevice(priv);
1582	if (dev == NULL) {
1583		result = -ENODEV;
1584		goto out_ccw2;
1585	}
1586
1587	for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1588		priv->channel[direction] =
1589			channel_get(type, direction == CTCM_READ ?
1590				read_id : write_id, direction);
1591		if (priv->channel[direction] == NULL) {
1592			if (direction == CTCM_WRITE)
1593				channel_free(priv->channel[CTCM_READ]);
1594			result = -ENODEV;
1595			goto out_dev;
1596		}
1597		priv->channel[direction]->netdev = dev;
1598		priv->channel[direction]->protocol = priv->protocol;
1599		priv->channel[direction]->max_bufsize = priv->buffer_size;
1600	}
1601	/* sysfs magic */
1602	SET_NETDEV_DEV(dev, &cgdev->dev);
1603
1604	if (register_netdev(dev)) {
1605		result = -ENODEV;
1606		goto out_dev;
1607	}
1608
1609	strlcpy(priv->fsm->name, dev->name, sizeof(priv->fsm->name));
1610
1611	dev_info(&dev->dev,
1612		"setup OK : r/w = %s/%s, protocol : %d\n",
1613			priv->channel[CTCM_READ]->id,
1614			priv->channel[CTCM_WRITE]->id, priv->protocol);
1615
1616	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1617		"setup(%s) OK : r/w = %s/%s, protocol : %d", dev->name,
1618			priv->channel[CTCM_READ]->id,
1619			priv->channel[CTCM_WRITE]->id, priv->protocol);
1620
1621	return 0;
1622out_dev:
1623	ctcm_free_netdevice(dev);
1624out_ccw2:
1625	ccw_device_set_offline(cgdev->cdev[1]);
1626out_ccw1:
1627	ccw_device_set_offline(cgdev->cdev[0]);
1628out_remove_channel2:
1629	readc = channel_get(type, read_id, CTCM_READ);
1630	channel_remove(readc);
1631out_remove_channel1:
1632	writec = channel_get(type, write_id, CTCM_WRITE);
1633	channel_remove(writec);
1634out_err_result:
1635	return result;
1636}
1637
1638/**
1639 * Shutdown an interface.
1640 *
1641 *  cgdev	Device to be shut down.
1642 *
1643 * returns 0 on success, !0 on failure.
1644 */
1645static int ctcm_shutdown_device(struct ccwgroup_device *cgdev)
1646{
1647	struct ctcm_priv *priv;
1648	struct net_device *dev;
1649
1650	priv = dev_get_drvdata(&cgdev->dev);
1651	if (!priv)
1652		return -ENODEV;
1653
1654	if (priv->channel[CTCM_READ]) {
1655		dev = priv->channel[CTCM_READ]->netdev;
1656		CTCM_DBF_DEV(SETUP, dev, "");
1657		/* Close the device */
1658		ctcm_close(dev);
1659		dev->flags &= ~IFF_RUNNING;
1660		channel_free(priv->channel[CTCM_READ]);
1661	} else
1662		dev = NULL;
1663
1664	if (priv->channel[CTCM_WRITE])
1665		channel_free(priv->channel[CTCM_WRITE]);
1666
1667	if (dev) {
1668		unregister_netdev(dev);
1669		ctcm_free_netdevice(dev);
1670	}
1671
1672	if (priv->fsm)
1673		kfree_fsm(priv->fsm);
1674
1675	ccw_device_set_offline(cgdev->cdev[1]);
1676	ccw_device_set_offline(cgdev->cdev[0]);
1677	channel_remove(priv->channel[CTCM_READ]);
1678	channel_remove(priv->channel[CTCM_WRITE]);
1679	priv->channel[CTCM_READ] = priv->channel[CTCM_WRITE] = NULL;
1680
1681	return 0;
1682
1683}
1684
1685
1686static void ctcm_remove_device(struct ccwgroup_device *cgdev)
1687{
1688	struct ctcm_priv *priv = dev_get_drvdata(&cgdev->dev);
1689
1690	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1691			"removing device %p, proto : %d",
1692			cgdev, priv->protocol);
1693
1694	if (cgdev->state == CCWGROUP_ONLINE)
1695		ctcm_shutdown_device(cgdev);
1696	dev_set_drvdata(&cgdev->dev, NULL);
1697	kfree(priv);
1698	put_device(&cgdev->dev);
1699}
1700
1701static struct ccw_device_id ctcm_ids[] = {
1702	{CCW_DEVICE(0x3088, 0x08), .driver_info = ctcm_channel_type_parallel},
1703	{CCW_DEVICE(0x3088, 0x1e), .driver_info = ctcm_channel_type_ficon},
1704	{CCW_DEVICE(0x3088, 0x1f), .driver_info = ctcm_channel_type_escon},
1705	{},
1706};
1707MODULE_DEVICE_TABLE(ccw, ctcm_ids);
1708
1709static struct ccw_driver ctcm_ccw_driver = {
1710	.driver = {
1711		.owner	= THIS_MODULE,
1712		.name	= "ctcm",
1713	},
1714	.ids	= ctcm_ids,
1715	.probe	= ccwgroup_probe_ccwdev,
1716	.remove	= ccwgroup_remove_ccwdev,
1717	.int_class = IRQIO_CTC,
1718};
1719
1720static struct ccwgroup_driver ctcm_group_driver = {
1721	.driver = {
1722		.owner	= THIS_MODULE,
1723		.name	= CTC_DRIVER_NAME,
1724	},
1725	.ccw_driver  = &ctcm_ccw_driver,
1726	.setup	     = ctcm_probe_device,
1727	.remove      = ctcm_remove_device,
1728	.set_online  = ctcm_new_device,
1729	.set_offline = ctcm_shutdown_device,
1730};
1731
1732static ssize_t group_store(struct device_driver *ddrv, const char *buf,
1733			   size_t count)
1734{
1735	int err;
1736
1737	err = ccwgroup_create_dev(ctcm_root_dev, &ctcm_group_driver, 2, buf);
1738	return err ? err : count;
1739}
1740static DRIVER_ATTR_WO(group);
1741
1742static struct attribute *ctcm_drv_attrs[] = {
1743	&driver_attr_group.attr,
1744	NULL,
1745};
1746static struct attribute_group ctcm_drv_attr_group = {
1747	.attrs = ctcm_drv_attrs,
1748};
1749static const struct attribute_group *ctcm_drv_attr_groups[] = {
1750	&ctcm_drv_attr_group,
1751	NULL,
1752};
1753
1754/*
1755 * Module related routines
1756 */
1757
1758/*
1759 * Prepare to be unloaded. Free IRQ's and release all resources.
1760 * This is called just before this module is unloaded. It is
1761 * not called, if the usage count is !0, so we don't need to check
1762 * for that.
1763 */
1764static void __exit ctcm_exit(void)
1765{
1766	ccwgroup_driver_unregister(&ctcm_group_driver);
1767	ccw_driver_unregister(&ctcm_ccw_driver);
1768	root_device_unregister(ctcm_root_dev);
1769	ctcm_unregister_dbf_views();
1770	pr_info("CTCM driver unloaded\n");
1771}
1772
1773/*
1774 * Print Banner.
1775 */
1776static void print_banner(void)
1777{
1778	pr_info("CTCM driver initialized\n");
1779}
1780
1781/**
1782 * Initialize module.
1783 * This is called just after the module is loaded.
1784 *
1785 * returns 0 on success, !0 on error.
1786 */
1787static int __init ctcm_init(void)
1788{
1789	int ret;
1790
1791	channels = NULL;
1792
1793	ret = ctcm_register_dbf_views();
1794	if (ret)
1795		goto out_err;
1796	ctcm_root_dev = root_device_register("ctcm");
1797	ret = PTR_ERR_OR_ZERO(ctcm_root_dev);
1798	if (ret)
1799		goto register_err;
1800	ret = ccw_driver_register(&ctcm_ccw_driver);
1801	if (ret)
1802		goto ccw_err;
1803	ctcm_group_driver.driver.groups = ctcm_drv_attr_groups;
1804	ret = ccwgroup_driver_register(&ctcm_group_driver);
1805	if (ret)
1806		goto ccwgroup_err;
1807	print_banner();
1808	return 0;
1809
1810ccwgroup_err:
1811	ccw_driver_unregister(&ctcm_ccw_driver);
1812ccw_err:
1813	root_device_unregister(ctcm_root_dev);
1814register_err:
1815	ctcm_unregister_dbf_views();
1816out_err:
1817	pr_err("%s / Initializing the ctcm device driver failed, ret = %d\n",
1818		__func__, ret);
1819	return ret;
1820}
1821
1822module_init(ctcm_init);
1823module_exit(ctcm_exit);
1824
1825MODULE_AUTHOR("Peter Tiedemann <ptiedem@de.ibm.com>");
1826MODULE_DESCRIPTION("Network driver for S/390 CTC + CTCMPC (SNA)");
1827MODULE_LICENSE("GPL");
1828
v5.14.15
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright IBM Corp. 2001, 2009
   4 * Author(s):
   5 *	Original CTC driver(s):
   6 *		Fritz Elfert (felfert@millenux.com)
   7 *		Dieter Wellerdiek (wel@de.ibm.com)
   8 *		Martin Schwidefsky (schwidefsky@de.ibm.com)
   9 *		Denis Joseph Barrow (barrow_dj@yahoo.com)
  10 *		Jochen Roehrig (roehrig@de.ibm.com)
  11 *		Cornelia Huck <cornelia.huck@de.ibm.com>
  12 *	MPC additions:
  13 *		Belinda Thompson (belindat@us.ibm.com)
  14 *		Andy Richter (richtera@us.ibm.com)
  15 *	Revived by:
  16 *		Peter Tiedemann (ptiedem@de.ibm.com)
  17 */
  18
  19#undef DEBUG
  20#undef DEBUGDATA
  21#undef DEBUGCCW
  22
  23#define KMSG_COMPONENT "ctcm"
  24#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  25
  26#include <linux/module.h>
  27#include <linux/init.h>
  28#include <linux/kernel.h>
  29#include <linux/slab.h>
  30#include <linux/errno.h>
  31#include <linux/types.h>
  32#include <linux/interrupt.h>
  33#include <linux/timer.h>
  34#include <linux/bitops.h>
  35
  36#include <linux/signal.h>
  37#include <linux/string.h>
  38
  39#include <linux/ip.h>
  40#include <linux/if_arp.h>
  41#include <linux/tcp.h>
  42#include <linux/skbuff.h>
  43#include <linux/ctype.h>
  44#include <net/dst.h>
  45
  46#include <linux/io.h>
  47#include <asm/ccwdev.h>
  48#include <asm/ccwgroup.h>
  49#include <linux/uaccess.h>
  50
  51#include <asm/idals.h>
  52
  53#include "ctcm_fsms.h"
  54#include "ctcm_main.h"
  55
  56/* Some common global variables */
  57
  58/**
  59 * The root device for ctcm group devices
  60 */
  61static struct device *ctcm_root_dev;
  62
  63/*
  64 * Linked list of all detected channels.
  65 */
  66struct channel *channels;
  67
  68/**
  69 * Unpack a just received skb and hand it over to
  70 * upper layers.
  71 *
  72 *  ch		The channel where this skb has been received.
  73 *  pskb	The received skb.
  74 */
  75void ctcm_unpack_skb(struct channel *ch, struct sk_buff *pskb)
  76{
  77	struct net_device *dev = ch->netdev;
  78	struct ctcm_priv *priv = dev->ml_priv;
  79	__u16 len = *((__u16 *) pskb->data);
  80
  81	skb_put(pskb, 2 + LL_HEADER_LENGTH);
  82	skb_pull(pskb, 2);
  83	pskb->dev = dev;
  84	pskb->ip_summed = CHECKSUM_UNNECESSARY;
  85	while (len > 0) {
  86		struct sk_buff *skb;
  87		int skblen;
  88		struct ll_header *header = (struct ll_header *)pskb->data;
  89
  90		skb_pull(pskb, LL_HEADER_LENGTH);
  91		if ((ch->protocol == CTCM_PROTO_S390) &&
  92		    (header->type != ETH_P_IP)) {
  93			if (!(ch->logflags & LOG_FLAG_ILLEGALPKT)) {
  94				ch->logflags |= LOG_FLAG_ILLEGALPKT;
  95				/*
  96				 * Check packet type only if we stick strictly
  97				 * to S/390's protocol of OS390. This only
  98				 * supports IP. Otherwise allow any packet
  99				 * type.
 100				 */
 101				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 102					"%s(%s): Illegal packet type 0x%04x"
 103					" - dropping",
 104					CTCM_FUNTAIL, dev->name, header->type);
 105			}
 106			priv->stats.rx_dropped++;
 107			priv->stats.rx_frame_errors++;
 108			return;
 109		}
 110		pskb->protocol = cpu_to_be16(header->type);
 111		if ((header->length <= LL_HEADER_LENGTH) ||
 112		    (len <= LL_HEADER_LENGTH)) {
 113			if (!(ch->logflags & LOG_FLAG_ILLEGALSIZE)) {
 114				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 115					"%s(%s): Illegal packet size %d(%d,%d)"
 116					"- dropping",
 117					CTCM_FUNTAIL, dev->name,
 118					header->length, dev->mtu, len);
 119				ch->logflags |= LOG_FLAG_ILLEGALSIZE;
 120			}
 121
 122			priv->stats.rx_dropped++;
 123			priv->stats.rx_length_errors++;
 124			return;
 125		}
 126		header->length -= LL_HEADER_LENGTH;
 127		len -= LL_HEADER_LENGTH;
 128		if ((header->length > skb_tailroom(pskb)) ||
 129		    (header->length > len)) {
 130			if (!(ch->logflags & LOG_FLAG_OVERRUN)) {
 131				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 132					"%s(%s): Packet size %d (overrun)"
 133					" - dropping", CTCM_FUNTAIL,
 134						dev->name, header->length);
 135				ch->logflags |= LOG_FLAG_OVERRUN;
 136			}
 137
 138			priv->stats.rx_dropped++;
 139			priv->stats.rx_length_errors++;
 140			return;
 141		}
 142		skb_put(pskb, header->length);
 143		skb_reset_mac_header(pskb);
 144		len -= header->length;
 145		skb = dev_alloc_skb(pskb->len);
 146		if (!skb) {
 147			if (!(ch->logflags & LOG_FLAG_NOMEM)) {
 148				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 149					"%s(%s): MEMORY allocation error",
 150						CTCM_FUNTAIL, dev->name);
 151				ch->logflags |= LOG_FLAG_NOMEM;
 152			}
 153			priv->stats.rx_dropped++;
 154			return;
 155		}
 156		skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
 157					  pskb->len);
 158		skb_reset_mac_header(skb);
 159		skb->dev = pskb->dev;
 160		skb->protocol = pskb->protocol;
 161		pskb->ip_summed = CHECKSUM_UNNECESSARY;
 162		skblen = skb->len;
 163		/*
 164		 * reset logflags
 165		 */
 166		ch->logflags = 0;
 167		priv->stats.rx_packets++;
 168		priv->stats.rx_bytes += skblen;
 169		netif_rx_ni(skb);
 170		if (len > 0) {
 171			skb_pull(pskb, header->length);
 172			if (skb_tailroom(pskb) < LL_HEADER_LENGTH) {
 173				CTCM_DBF_DEV_NAME(TRACE, dev,
 174					"Overrun in ctcm_unpack_skb");
 175				ch->logflags |= LOG_FLAG_OVERRUN;
 176				return;
 177			}
 178			skb_put(pskb, LL_HEADER_LENGTH);
 179		}
 180	}
 181}
 182
 183/**
 184 * Release a specific channel in the channel list.
 185 *
 186 *  ch		Pointer to channel struct to be released.
 187 */
 188static void channel_free(struct channel *ch)
 189{
 190	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s)", CTCM_FUNTAIL, ch->id);
 191	ch->flags &= ~CHANNEL_FLAGS_INUSE;
 192	fsm_newstate(ch->fsm, CTC_STATE_IDLE);
 193}
 194
 195/**
 196 * Remove a specific channel in the channel list.
 197 *
 198 *  ch		Pointer to channel struct to be released.
 199 */
 200static void channel_remove(struct channel *ch)
 201{
 202	struct channel **c = &channels;
 203	char chid[CTCM_ID_SIZE+1];
 204	int ok = 0;
 205
 206	if (ch == NULL)
 207		return;
 208	else
 209		strncpy(chid, ch->id, CTCM_ID_SIZE);
 210
 211	channel_free(ch);
 212	while (*c) {
 213		if (*c == ch) {
 214			*c = ch->next;
 215			fsm_deltimer(&ch->timer);
 216			if (IS_MPC(ch))
 217				fsm_deltimer(&ch->sweep_timer);
 218
 219			kfree_fsm(ch->fsm);
 220			clear_normalized_cda(&ch->ccw[4]);
 221			if (ch->trans_skb != NULL) {
 222				clear_normalized_cda(&ch->ccw[1]);
 223				dev_kfree_skb_any(ch->trans_skb);
 224			}
 225			if (IS_MPC(ch)) {
 226				tasklet_kill(&ch->ch_tasklet);
 227				tasklet_kill(&ch->ch_disc_tasklet);
 228				kfree(ch->discontact_th);
 229			}
 230			kfree(ch->ccw);
 231			kfree(ch->irb);
 232			kfree(ch);
 233			ok = 1;
 234			break;
 235		}
 236		c = &((*c)->next);
 237	}
 238
 239	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s) %s", CTCM_FUNTAIL,
 240			chid, ok ? "OK" : "failed");
 241}
 242
 243/**
 244 * Get a specific channel from the channel list.
 245 *
 246 *  type	Type of channel we are interested in.
 247 *  id		Id of channel we are interested in.
 248 *  direction	Direction we want to use this channel for.
 249 *
 250 * returns Pointer to a channel or NULL if no matching channel available.
 251 */
 252static struct channel *channel_get(enum ctcm_channel_types type,
 253					char *id, int direction)
 254{
 255	struct channel *ch = channels;
 256
 257	while (ch && (strncmp(ch->id, id, CTCM_ID_SIZE) || (ch->type != type)))
 258		ch = ch->next;
 259	if (!ch) {
 260		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 261				"%s(%d, %s, %d) not found in channel list\n",
 262				CTCM_FUNTAIL, type, id, direction);
 263	} else {
 264		if (ch->flags & CHANNEL_FLAGS_INUSE)
 265			ch = NULL;
 266		else {
 267			ch->flags |= CHANNEL_FLAGS_INUSE;
 268			ch->flags &= ~CHANNEL_FLAGS_RWMASK;
 269			ch->flags |= (direction == CTCM_WRITE)
 270			    ? CHANNEL_FLAGS_WRITE : CHANNEL_FLAGS_READ;
 271			fsm_newstate(ch->fsm, CTC_STATE_STOPPED);
 272		}
 273	}
 274	return ch;
 275}
 276
 277static long ctcm_check_irb_error(struct ccw_device *cdev, struct irb *irb)
 278{
 279	if (!IS_ERR(irb))
 280		return 0;
 281
 282	CTCM_DBF_TEXT_(ERROR, CTC_DBF_WARN,
 283			"irb error %ld on device %s\n",
 284				PTR_ERR(irb), dev_name(&cdev->dev));
 285
 286	switch (PTR_ERR(irb)) {
 287	case -EIO:
 288		dev_err(&cdev->dev,
 289			"An I/O-error occurred on the CTCM device\n");
 290		break;
 291	case -ETIMEDOUT:
 292		dev_err(&cdev->dev,
 293			"An adapter hardware operation timed out\n");
 294		break;
 295	default:
 296		dev_err(&cdev->dev,
 297			"An error occurred on the adapter hardware\n");
 298	}
 299	return PTR_ERR(irb);
 300}
 301
 302
 303/**
 304 * Check sense of a unit check.
 305 *
 306 *  ch		The channel, the sense code belongs to.
 307 *  sense	The sense code to inspect.
 308 */
 309static void ccw_unit_check(struct channel *ch, __u8 sense)
 310{
 311	CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
 312			"%s(%s): %02x",
 313				CTCM_FUNTAIL, ch->id, sense);
 314
 315	if (sense & SNS0_INTERVENTION_REQ) {
 316		if (sense & 0x01) {
 317			if (ch->sense_rc != 0x01) {
 318				pr_notice(
 319					"%s: The communication peer has "
 320					"disconnected\n", ch->id);
 321				ch->sense_rc = 0x01;
 322			}
 323			fsm_event(ch->fsm, CTC_EVENT_UC_RCRESET, ch);
 324		} else {
 325			if (ch->sense_rc != SNS0_INTERVENTION_REQ) {
 326				pr_notice(
 327					"%s: The remote operating system is "
 328					"not available\n", ch->id);
 329				ch->sense_rc = SNS0_INTERVENTION_REQ;
 330			}
 331			fsm_event(ch->fsm, CTC_EVENT_UC_RSRESET, ch);
 332		}
 333	} else if (sense & SNS0_EQUIPMENT_CHECK) {
 334		if (sense & SNS0_BUS_OUT_CHECK) {
 335			if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 336				CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 337					"%s(%s): remote HW error %02x",
 338						CTCM_FUNTAIL, ch->id, sense);
 339				ch->sense_rc = SNS0_BUS_OUT_CHECK;
 340			}
 341			fsm_event(ch->fsm, CTC_EVENT_UC_HWFAIL, ch);
 342		} else {
 343			if (ch->sense_rc != SNS0_EQUIPMENT_CHECK) {
 344				CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 345					"%s(%s): remote read parity error %02x",
 346						CTCM_FUNTAIL, ch->id, sense);
 347				ch->sense_rc = SNS0_EQUIPMENT_CHECK;
 348			}
 349			fsm_event(ch->fsm, CTC_EVENT_UC_RXPARITY, ch);
 350		}
 351	} else if (sense & SNS0_BUS_OUT_CHECK) {
 352		if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
 353			CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 354				"%s(%s): BUS OUT error %02x",
 355					CTCM_FUNTAIL, ch->id, sense);
 356			ch->sense_rc = SNS0_BUS_OUT_CHECK;
 357		}
 358		if (sense & 0x04)	/* data-streaming timeout */
 359			fsm_event(ch->fsm, CTC_EVENT_UC_TXTIMEOUT, ch);
 360		else			/* Data-transfer parity error */
 361			fsm_event(ch->fsm, CTC_EVENT_UC_TXPARITY, ch);
 362	} else if (sense & SNS0_CMD_REJECT) {
 363		if (ch->sense_rc != SNS0_CMD_REJECT) {
 364			CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 365				"%s(%s): Command rejected",
 366						CTCM_FUNTAIL, ch->id);
 367			ch->sense_rc = SNS0_CMD_REJECT;
 368		}
 369	} else if (sense == 0) {
 370		CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 371			"%s(%s): Unit check ZERO",
 372					CTCM_FUNTAIL, ch->id);
 373		fsm_event(ch->fsm, CTC_EVENT_UC_ZERO, ch);
 374	} else {
 375		CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
 376			"%s(%s): Unit check code %02x unknown",
 377					CTCM_FUNTAIL, ch->id, sense);
 378		fsm_event(ch->fsm, CTC_EVENT_UC_UNKNOWN, ch);
 379	}
 380}
 381
 382int ctcm_ch_alloc_buffer(struct channel *ch)
 383{
 384	clear_normalized_cda(&ch->ccw[1]);
 385	ch->trans_skb = __dev_alloc_skb(ch->max_bufsize, GFP_ATOMIC | GFP_DMA);
 386	if (ch->trans_skb == NULL) {
 387		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 388			"%s(%s): %s trans_skb allocation error",
 389			CTCM_FUNTAIL, ch->id,
 390			(CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ?
 391				"RX" : "TX");
 392		return -ENOMEM;
 393	}
 394
 395	ch->ccw[1].count = ch->max_bufsize;
 396	if (set_normalized_cda(&ch->ccw[1], ch->trans_skb->data)) {
 397		dev_kfree_skb(ch->trans_skb);
 398		ch->trans_skb = NULL;
 399		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 400			"%s(%s): %s set norm_cda failed",
 401			CTCM_FUNTAIL, ch->id,
 402			(CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ?
 403				"RX" : "TX");
 404		return -ENOMEM;
 405	}
 406
 407	ch->ccw[1].count = 0;
 408	ch->trans_skb_data = ch->trans_skb->data;
 409	ch->flags &= ~CHANNEL_FLAGS_BUFSIZE_CHANGED;
 410	return 0;
 411}
 412
 413/*
 414 * Interface API for upper network layers
 415 */
 416
 417/**
 418 * Open an interface.
 419 * Called from generic network layer when ifconfig up is run.
 420 *
 421 *  dev		Pointer to interface struct.
 422 *
 423 * returns 0 on success, -ERRNO on failure. (Never fails.)
 424 */
 425int ctcm_open(struct net_device *dev)
 426{
 427	struct ctcm_priv *priv = dev->ml_priv;
 428
 429	CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 430	if (!IS_MPC(priv))
 431		fsm_event(priv->fsm,	DEV_EVENT_START, dev);
 432	return 0;
 433}
 434
 435/**
 436 * Close an interface.
 437 * Called from generic network layer when ifconfig down is run.
 438 *
 439 *  dev		Pointer to interface struct.
 440 *
 441 * returns 0 on success, -ERRNO on failure. (Never fails.)
 442 */
 443int ctcm_close(struct net_device *dev)
 444{
 445	struct ctcm_priv *priv = dev->ml_priv;
 446
 447	CTCMY_DBF_DEV_NAME(SETUP, dev, "");
 448	if (!IS_MPC(priv))
 449		fsm_event(priv->fsm, DEV_EVENT_STOP, dev);
 450	return 0;
 451}
 452
 453
 454/**
 455 * Transmit a packet.
 456 * This is a helper function for ctcm_tx().
 457 *
 458 *  ch		Channel to be used for sending.
 459 *  skb		Pointer to struct sk_buff of packet to send.
 460 *            The linklevel header has already been set up
 461 *            by ctcm_tx().
 462 *
 463 * returns 0 on success, -ERRNO on failure. (Never fails.)
 464 */
 465static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
 466{
 467	unsigned long saveflags;
 468	struct ll_header header;
 469	int rc = 0;
 470	__u16 block_len;
 471	int ccw_idx;
 472	struct sk_buff *nskb;
 473	unsigned long hi;
 474
 475	/* we need to acquire the lock for testing the state
 476	 * otherwise we can have an IRQ changing the state to
 477	 * TXIDLE after the test but before acquiring the lock.
 478	 */
 479	spin_lock_irqsave(&ch->collect_lock, saveflags);
 480	if (fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) {
 481		int l = skb->len + LL_HEADER_LENGTH;
 482
 483		if (ch->collect_len + l > ch->max_bufsize - 2) {
 484			spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 485			return -EBUSY;
 486		} else {
 487			refcount_inc(&skb->users);
 488			header.length = l;
 489			header.type = be16_to_cpu(skb->protocol);
 490			header.unused = 0;
 491			memcpy(skb_push(skb, LL_HEADER_LENGTH), &header,
 492			       LL_HEADER_LENGTH);
 493			skb_queue_tail(&ch->collect_queue, skb);
 494			ch->collect_len += l;
 495		}
 496		spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 497				goto done;
 498	}
 499	spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 500	/*
 501	 * Protect skb against beeing free'd by upper
 502	 * layers.
 503	 */
 504	refcount_inc(&skb->users);
 505	ch->prof.txlen += skb->len;
 506	header.length = skb->len + LL_HEADER_LENGTH;
 507	header.type = be16_to_cpu(skb->protocol);
 508	header.unused = 0;
 509	memcpy(skb_push(skb, LL_HEADER_LENGTH), &header, LL_HEADER_LENGTH);
 510	block_len = skb->len + 2;
 511	*((__u16 *)skb_push(skb, 2)) = block_len;
 512
 513	/*
 514	 * IDAL support in CTCM is broken, so we have to
 515	 * care about skb's above 2G ourselves.
 516	 */
 517	hi = ((unsigned long)skb_tail_pointer(skb) + LL_HEADER_LENGTH) >> 31;
 518	if (hi) {
 519		nskb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 520		if (!nskb) {
 521			refcount_dec(&skb->users);
 522			skb_pull(skb, LL_HEADER_LENGTH + 2);
 523			ctcm_clear_busy(ch->netdev);
 524			return -ENOMEM;
 525		} else {
 526			skb_put_data(nskb, skb->data, skb->len);
 527			refcount_inc(&nskb->users);
 528			refcount_dec(&skb->users);
 529			dev_kfree_skb_irq(skb);
 530			skb = nskb;
 531		}
 532	}
 533
 534	ch->ccw[4].count = block_len;
 535	if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 536		/*
 537		 * idal allocation failed, try via copying to
 538		 * trans_skb. trans_skb usually has a pre-allocated
 539		 * idal.
 540		 */
 541		if (ctcm_checkalloc_buffer(ch)) {
 542			/*
 543			 * Remove our header. It gets added
 544			 * again on retransmit.
 545			 */
 546			refcount_dec(&skb->users);
 547			skb_pull(skb, LL_HEADER_LENGTH + 2);
 548			ctcm_clear_busy(ch->netdev);
 549			return -ENOMEM;
 550		}
 551
 552		skb_reset_tail_pointer(ch->trans_skb);
 553		ch->trans_skb->len = 0;
 554		ch->ccw[1].count = skb->len;
 555		skb_copy_from_linear_data(skb,
 556				skb_put(ch->trans_skb, skb->len), skb->len);
 557		refcount_dec(&skb->users);
 558		dev_kfree_skb_irq(skb);
 559		ccw_idx = 0;
 560	} else {
 561		skb_queue_tail(&ch->io_queue, skb);
 562		ccw_idx = 3;
 563	}
 564	if (do_debug_ccw)
 565		ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
 566					sizeof(struct ccw1) * 3);
 567	ch->retry = 0;
 568	fsm_newstate(ch->fsm, CTC_STATE_TX);
 569	fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 570	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 571	ch->prof.send_stamp = jiffies;
 572	rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx], 0, 0xff, 0);
 573	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 574	if (ccw_idx == 3)
 575		ch->prof.doios_single++;
 576	if (rc != 0) {
 577		fsm_deltimer(&ch->timer);
 578		ctcm_ccw_check_rc(ch, rc, "single skb TX");
 579		if (ccw_idx == 3)
 580			skb_dequeue_tail(&ch->io_queue);
 581		/*
 582		 * Remove our header. It gets added
 583		 * again on retransmit.
 584		 */
 585		skb_pull(skb, LL_HEADER_LENGTH + 2);
 586	} else if (ccw_idx == 0) {
 587		struct net_device *dev = ch->netdev;
 588		struct ctcm_priv *priv = dev->ml_priv;
 589		priv->stats.tx_packets++;
 590		priv->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
 591	}
 592done:
 593	ctcm_clear_busy(ch->netdev);
 594	return rc;
 595}
 596
 597static void ctcmpc_send_sweep_req(struct channel *rch)
 598{
 599	struct net_device *dev = rch->netdev;
 600	struct ctcm_priv *priv;
 601	struct mpc_group *grp;
 602	struct th_sweep *header;
 603	struct sk_buff *sweep_skb;
 604	struct channel *ch;
 605	/* int rc = 0; */
 606
 607	priv = dev->ml_priv;
 608	grp = priv->mpcg;
 609	ch = priv->channel[CTCM_WRITE];
 610
 611	/* sweep processing is not complete until response and request */
 612	/* has completed for all read channels in group		       */
 613	if (grp->in_sweep == 0) {
 614		grp->in_sweep = 1;
 615		grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
 616		grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
 617	}
 618
 619	sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
 620
 621	if (sweep_skb == NULL)	{
 622		/* rc = -ENOMEM; */
 623				goto nomem;
 624	}
 625
 626	header = skb_put_zero(sweep_skb, TH_SWEEP_LENGTH);
 
 
 
 
 
 
 
 
 627	header->th.th_ch_flag	= TH_SWEEP_REQ;  /* 0x0f */
 
 
 
 628	header->sw.th_last_seq	= ch->th_seq_num;
 629
 
 
 
 
 630	netif_trans_update(dev);
 631	skb_queue_tail(&ch->sweep_queue, sweep_skb);
 632
 633	fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
 634
 635	return;
 636
 637nomem:
 638	grp->in_sweep = 0;
 639	ctcm_clear_busy(dev);
 640	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 641
 642	return;
 643}
 644
 645/*
 646 * MPC mode version of transmit_skb
 647 */
 648static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
 649{
 650	struct pdu *p_header;
 651	struct net_device *dev = ch->netdev;
 652	struct ctcm_priv *priv = dev->ml_priv;
 653	struct mpc_group *grp = priv->mpcg;
 654	struct th_header *header;
 655	struct sk_buff *nskb;
 656	int rc = 0;
 657	int ccw_idx;
 658	unsigned long hi;
 659	unsigned long saveflags = 0;	/* avoids compiler warning */
 660
 661	CTCM_PR_DEBUG("Enter %s: %s, cp=%i ch=0x%p id=%s state=%s\n",
 662			__func__, dev->name, smp_processor_id(), ch,
 663					ch->id, fsm_getstate_str(ch->fsm));
 664
 665	if ((fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) || grp->in_sweep) {
 666		spin_lock_irqsave(&ch->collect_lock, saveflags);
 667		refcount_inc(&skb->users);
 
 
 
 
 
 
 668
 669		p_header = skb_push(skb, PDU_HEADER_LENGTH);
 670		p_header->pdu_offset = skb->len - PDU_HEADER_LENGTH;
 671		p_header->pdu_proto = 0x01;
 
 672		if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
 673			p_header->pdu_flag = PDU_FIRST | PDU_CNTL;
 674		} else {
 675			p_header->pdu_flag = PDU_FIRST;
 676		}
 677		p_header->pdu_seq = 0;
 
 
 678
 679		CTCM_PR_DEBUG("%s(%s): Put on collect_q - skb len: %04x \n"
 680				"pdu header and data for up to 32 bytes:\n",
 681				__func__, dev->name, skb->len);
 682		CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 683
 684		skb_queue_tail(&ch->collect_queue, skb);
 685		ch->collect_len += skb->len;
 
 686
 687		spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 688			goto done;
 689	}
 690
 691	/*
 692	 * Protect skb against beeing free'd by upper
 693	 * layers.
 694	 */
 695	refcount_inc(&skb->users);
 696
 697	/*
 698	 * IDAL support in CTCM is broken, so we have to
 699	 * care about skb's above 2G ourselves.
 700	 */
 701	hi = ((unsigned long)skb->tail + TH_HEADER_LENGTH) >> 31;
 702	if (hi) {
 703		nskb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
 704		if (!nskb) {
 705			goto nomem_exit;
 706		} else {
 707			skb_put_data(nskb, skb->data, skb->len);
 708			refcount_inc(&nskb->users);
 709			refcount_dec(&skb->users);
 710			dev_kfree_skb_irq(skb);
 711			skb = nskb;
 712		}
 713	}
 714
 715	p_header = skb_push(skb, PDU_HEADER_LENGTH);
 716	p_header->pdu_offset = skb->len - PDU_HEADER_LENGTH;
 
 
 
 
 717	p_header->pdu_proto = 0x01;
 
 718	p_header->pdu_seq = 0;
 719	if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
 720		p_header->pdu_flag = PDU_FIRST | PDU_CNTL;
 721	} else {
 722		p_header->pdu_flag = PDU_FIRST;
 723	}
 
 
 
 724
 725	if (ch->collect_len > 0) {
 726		spin_lock_irqsave(&ch->collect_lock, saveflags);
 727		skb_queue_tail(&ch->collect_queue, skb);
 728		ch->collect_len += skb->len;
 729		skb = skb_dequeue(&ch->collect_queue);
 730		ch->collect_len -= skb->len;
 731		spin_unlock_irqrestore(&ch->collect_lock, saveflags);
 732	}
 733
 734	p_header = (struct pdu *)skb->data;
 735	p_header->pdu_flag |= PDU_LAST;
 736
 737	ch->prof.txlen += skb->len - PDU_HEADER_LENGTH;
 738
 739	/* put the TH on the packet */
 740	header = skb_push(skb, TH_HEADER_LENGTH);
 741	memset(header, 0, TH_HEADER_LENGTH);
 742
 
 743	header->th_ch_flag = TH_HAS_PDU;  /* Normal data */
 
 
 744	ch->th_seq_num++;
 745	header->th_seq_num = ch->th_seq_num;
 746
 747	CTCM_PR_DBGDATA("%s(%s) ToVTAM_th_seq= %08x\n" ,
 748		       __func__, dev->name, ch->th_seq_num);
 749
 
 
 
 
 
 750	CTCM_PR_DBGDATA("%s(%s): skb len: %04x\n - pdu header and data for "
 751			"up to 32 bytes sent to vtam:\n",
 752				__func__, dev->name, skb->len);
 753	CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 754
 755	ch->ccw[4].count = skb->len;
 756	if (set_normalized_cda(&ch->ccw[4], skb->data)) {
 757		/*
 758		 * idal allocation failed, try via copying to trans_skb.
 759		 * trans_skb usually has a pre-allocated idal.
 760		 */
 761		if (ctcm_checkalloc_buffer(ch)) {
 762			/*
 763			 * Remove our header.
 764			 * It gets added again on retransmit.
 765			 */
 766				goto nomem_exit;
 767		}
 768
 769		skb_reset_tail_pointer(ch->trans_skb);
 770		ch->trans_skb->len = 0;
 771		ch->ccw[1].count = skb->len;
 772		skb_put_data(ch->trans_skb, skb->data, skb->len);
 773		refcount_dec(&skb->users);
 774		dev_kfree_skb_irq(skb);
 775		ccw_idx = 0;
 776		CTCM_PR_DBGDATA("%s(%s): trans_skb len: %04x\n"
 777				"up to 32 bytes sent to vtam:\n",
 778				__func__, dev->name, ch->trans_skb->len);
 779		CTCM_D3_DUMP((char *)ch->trans_skb->data,
 780				min_t(int, 32, ch->trans_skb->len));
 781	} else {
 782		skb_queue_tail(&ch->io_queue, skb);
 783		ccw_idx = 3;
 784	}
 785	ch->retry = 0;
 786	fsm_newstate(ch->fsm, CTC_STATE_TX);
 787	fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
 788
 789	if (do_debug_ccw)
 790		ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
 791					sizeof(struct ccw1) * 3);
 792
 793	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
 794	ch->prof.send_stamp = jiffies;
 795	rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx], 0, 0xff, 0);
 796	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
 797	if (ccw_idx == 3)
 798		ch->prof.doios_single++;
 799	if (rc != 0) {
 800		fsm_deltimer(&ch->timer);
 801		ctcm_ccw_check_rc(ch, rc, "single skb TX");
 802		if (ccw_idx == 3)
 803			skb_dequeue_tail(&ch->io_queue);
 804	} else if (ccw_idx == 0) {
 805		priv->stats.tx_packets++;
 806		priv->stats.tx_bytes += skb->len - TH_HEADER_LENGTH;
 807	}
 808	if (ch->th_seq_num > 0xf0000000)	/* Chose at random. */
 809		ctcmpc_send_sweep_req(ch);
 810
 811	goto done;
 812nomem_exit:
 813	CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_CRIT,
 814			"%s(%s): MEMORY allocation ERROR\n",
 815			CTCM_FUNTAIL, ch->id);
 816	rc = -ENOMEM;
 817	refcount_dec(&skb->users);
 818	dev_kfree_skb_any(skb);
 819	fsm_event(priv->mpcg->fsm, MPCG_EVENT_INOP, dev);
 820done:
 821	CTCM_PR_DEBUG("Exit %s(%s)\n", __func__, dev->name);
 822	return rc;
 823}
 824
 825/**
 826 * Start transmission of a packet.
 827 * Called from generic network device layer.
 828 *
 829 *  skb		Pointer to buffer containing the packet.
 830 *  dev		Pointer to interface struct.
 831 *
 832 * returns 0 if packet consumed, !0 if packet rejected.
 833 *         Note: If we return !0, then the packet is free'd by
 834 *               the generic network layer.
 835 */
 836/* first merge version - leaving both functions separated */
 837static int ctcm_tx(struct sk_buff *skb, struct net_device *dev)
 838{
 839	struct ctcm_priv *priv = dev->ml_priv;
 840
 841	if (skb == NULL) {
 842		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 843				"%s(%s): NULL sk_buff passed",
 844					CTCM_FUNTAIL, dev->name);
 845		priv->stats.tx_dropped++;
 846		return NETDEV_TX_OK;
 847	}
 848	if (skb_headroom(skb) < (LL_HEADER_LENGTH + 2)) {
 849		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
 850			"%s(%s): Got sk_buff with head room < %ld bytes",
 851			CTCM_FUNTAIL, dev->name, LL_HEADER_LENGTH + 2);
 852		dev_kfree_skb(skb);
 853		priv->stats.tx_dropped++;
 854		return NETDEV_TX_OK;
 855	}
 856
 857	/*
 858	 * If channels are not running, try to restart them
 859	 * and throw away packet.
 860	 */
 861	if (fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) {
 862		fsm_event(priv->fsm, DEV_EVENT_START, dev);
 863		dev_kfree_skb(skb);
 864		priv->stats.tx_dropped++;
 865		priv->stats.tx_errors++;
 866		priv->stats.tx_carrier_errors++;
 867		return NETDEV_TX_OK;
 868	}
 869
 870	if (ctcm_test_and_set_busy(dev))
 871		return NETDEV_TX_BUSY;
 872
 873	netif_trans_update(dev);
 874	if (ctcm_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0)
 875		return NETDEV_TX_BUSY;
 876	return NETDEV_TX_OK;
 877}
 878
 879/* unmerged MPC variant of ctcm_tx */
 880static int ctcmpc_tx(struct sk_buff *skb, struct net_device *dev)
 881{
 882	int len = 0;
 883	struct ctcm_priv *priv = dev->ml_priv;
 884	struct mpc_group *grp  = priv->mpcg;
 885	struct sk_buff *newskb = NULL;
 886
 887	/*
 888	 * Some sanity checks ...
 889	 */
 890	if (skb == NULL) {
 891		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 892			"%s(%s): NULL sk_buff passed",
 893					CTCM_FUNTAIL, dev->name);
 894		priv->stats.tx_dropped++;
 895					goto done;
 896	}
 897	if (skb_headroom(skb) < (TH_HEADER_LENGTH + PDU_HEADER_LENGTH)) {
 898		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 899			"%s(%s): Got sk_buff with head room < %ld bytes",
 900			CTCM_FUNTAIL, dev->name,
 901				TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 902
 903		CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
 904
 905		len =  skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
 906		newskb = __dev_alloc_skb(len, GFP_ATOMIC | GFP_DMA);
 907
 908		if (!newskb) {
 909			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
 910				"%s: %s: __dev_alloc_skb failed",
 911						__func__, dev->name);
 912
 913			dev_kfree_skb_any(skb);
 914			priv->stats.tx_dropped++;
 915			priv->stats.tx_errors++;
 916			priv->stats.tx_carrier_errors++;
 917			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 918					goto done;
 919		}
 920		newskb->protocol = skb->protocol;
 921		skb_reserve(newskb, TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
 922		skb_put_data(newskb, skb->data, skb->len);
 923		dev_kfree_skb_any(skb);
 924		skb = newskb;
 925	}
 926
 927	/*
 928	 * If channels are not running,
 929	 * notify anybody about a link failure and throw
 930	 * away packet.
 931	 */
 932	if ((fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) ||
 933	   (fsm_getstate(grp->fsm) <  MPCG_STATE_XID2INITW)) {
 934		dev_kfree_skb_any(skb);
 935		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 936			"%s(%s): inactive MPCGROUP - dropped",
 937					CTCM_FUNTAIL, dev->name);
 938		priv->stats.tx_dropped++;
 939		priv->stats.tx_errors++;
 940		priv->stats.tx_carrier_errors++;
 941					goto done;
 942	}
 943
 944	if (ctcm_test_and_set_busy(dev)) {
 945		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 946			"%s(%s): device busy - dropped",
 947					CTCM_FUNTAIL, dev->name);
 948		dev_kfree_skb_any(skb);
 949		priv->stats.tx_dropped++;
 950		priv->stats.tx_errors++;
 951		priv->stats.tx_carrier_errors++;
 952		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 953					goto done;
 954	}
 955
 956	netif_trans_update(dev);
 957	if (ctcmpc_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0) {
 958		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
 959			"%s(%s): device error - dropped",
 960					CTCM_FUNTAIL, dev->name);
 961		dev_kfree_skb_any(skb);
 962		priv->stats.tx_dropped++;
 963		priv->stats.tx_errors++;
 964		priv->stats.tx_carrier_errors++;
 965		ctcm_clear_busy(dev);
 966		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
 967					goto done;
 968	}
 969	ctcm_clear_busy(dev);
 970done:
 971	if (do_debug)
 972		MPC_DBF_DEV_NAME(TRACE, dev, "exit");
 973
 974	return NETDEV_TX_OK;	/* handle freeing of skb here */
 975}
 976
 977
 978/**
 979 * Sets MTU of an interface.
 980 *
 981 *  dev		Pointer to interface struct.
 982 *  new_mtu	The new MTU to use for this interface.
 983 *
 984 * returns 0 on success, -EINVAL if MTU is out of valid range.
 985 *         (valid range is 576 .. 65527). If VM is on the
 986 *         remote side, maximum MTU is 32760, however this is
 987 *         not checked here.
 988 */
 989static int ctcm_change_mtu(struct net_device *dev, int new_mtu)
 990{
 991	struct ctcm_priv *priv;
 992	int max_bufsize;
 993
 994	priv = dev->ml_priv;
 995	max_bufsize = priv->channel[CTCM_READ]->max_bufsize;
 996
 997	if (IS_MPC(priv)) {
 998		if (new_mtu > max_bufsize - TH_HEADER_LENGTH)
 999			return -EINVAL;
1000		dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1001	} else {
1002		if (new_mtu > max_bufsize - LL_HEADER_LENGTH - 2)
1003			return -EINVAL;
1004		dev->hard_header_len = LL_HEADER_LENGTH + 2;
1005	}
1006	dev->mtu = new_mtu;
1007	return 0;
1008}
1009
1010/**
1011 * Returns interface statistics of a device.
1012 *
1013 *  dev		Pointer to interface struct.
1014 *
1015 * returns Pointer to stats struct of this interface.
1016 */
1017static struct net_device_stats *ctcm_stats(struct net_device *dev)
1018{
1019	return &((struct ctcm_priv *)dev->ml_priv)->stats;
1020}
1021
1022static void ctcm_free_netdevice(struct net_device *dev)
1023{
1024	struct ctcm_priv *priv;
1025	struct mpc_group *grp;
1026
1027	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1028			"%s(%s)", CTCM_FUNTAIL, dev->name);
1029	priv = dev->ml_priv;
1030	if (priv) {
1031		grp = priv->mpcg;
1032		if (grp) {
1033			if (grp->fsm)
1034				kfree_fsm(grp->fsm);
1035			dev_kfree_skb(grp->xid_skb);
1036			dev_kfree_skb(grp->rcvd_xid_skb);
1037			tasklet_kill(&grp->mpc_tasklet2);
1038			kfree(grp);
1039			priv->mpcg = NULL;
1040		}
1041		if (priv->fsm) {
1042			kfree_fsm(priv->fsm);
1043			priv->fsm = NULL;
1044		}
1045		kfree(priv->xid);
1046		priv->xid = NULL;
1047	/*
1048	 * Note: kfree(priv); is done in "opposite" function of
1049	 * allocator function probe_device which is remove_device.
1050	 */
1051	}
1052#ifdef MODULE
1053	free_netdev(dev);
1054#endif
1055}
1056
1057struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv);
1058
1059static const struct net_device_ops ctcm_netdev_ops = {
1060	.ndo_open		= ctcm_open,
1061	.ndo_stop		= ctcm_close,
1062	.ndo_get_stats		= ctcm_stats,
1063	.ndo_change_mtu	   	= ctcm_change_mtu,
1064	.ndo_start_xmit		= ctcm_tx,
1065};
1066
1067static const struct net_device_ops ctcm_mpc_netdev_ops = {
1068	.ndo_open		= ctcm_open,
1069	.ndo_stop		= ctcm_close,
1070	.ndo_get_stats		= ctcm_stats,
1071	.ndo_change_mtu	   	= ctcm_change_mtu,
1072	.ndo_start_xmit		= ctcmpc_tx,
1073};
1074
1075static void ctcm_dev_setup(struct net_device *dev)
1076{
1077	dev->type = ARPHRD_SLIP;
1078	dev->tx_queue_len = 100;
1079	dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1080	dev->min_mtu = 576;
1081	dev->max_mtu = 65527;
1082}
1083
1084/*
1085 * Initialize everything of the net device except the name and the
1086 * channel structs.
1087 */
1088static struct net_device *ctcm_init_netdevice(struct ctcm_priv *priv)
1089{
1090	struct net_device *dev;
1091	struct mpc_group *grp;
1092	if (!priv)
1093		return NULL;
1094
1095	if (IS_MPC(priv))
1096		dev = alloc_netdev(0, MPC_DEVICE_GENE, NET_NAME_UNKNOWN,
1097				   ctcm_dev_setup);
1098	else
1099		dev = alloc_netdev(0, CTC_DEVICE_GENE, NET_NAME_UNKNOWN,
1100				   ctcm_dev_setup);
1101
1102	if (!dev) {
1103		CTCM_DBF_TEXT_(ERROR, CTC_DBF_CRIT,
1104			"%s: MEMORY allocation ERROR",
1105			CTCM_FUNTAIL);
1106		return NULL;
1107	}
1108	dev->ml_priv = priv;
1109	priv->fsm = init_fsm("ctcmdev", dev_state_names, dev_event_names,
1110				CTCM_NR_DEV_STATES, CTCM_NR_DEV_EVENTS,
1111				dev_fsm, dev_fsm_len, GFP_KERNEL);
1112	if (priv->fsm == NULL) {
1113		CTCMY_DBF_DEV(SETUP, dev, "init_fsm error");
1114		free_netdev(dev);
1115		return NULL;
1116	}
1117	fsm_newstate(priv->fsm, DEV_STATE_STOPPED);
1118	fsm_settimer(priv->fsm, &priv->restart_timer);
1119
1120	if (IS_MPC(priv)) {
1121		/*  MPC Group Initializations  */
1122		grp = ctcmpc_init_mpc_group(priv);
1123		if (grp == NULL) {
1124			MPC_DBF_DEV(SETUP, dev, "init_mpc_group error");
1125			free_netdev(dev);
1126			return NULL;
1127		}
1128		tasklet_init(&grp->mpc_tasklet2,
1129				mpc_group_ready, (unsigned long)dev);
1130		dev->mtu = MPC_BUFSIZE_DEFAULT -
1131				TH_HEADER_LENGTH - PDU_HEADER_LENGTH;
1132
1133		dev->netdev_ops = &ctcm_mpc_netdev_ops;
1134		dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1135		priv->buffer_size = MPC_BUFSIZE_DEFAULT;
1136	} else {
1137		dev->mtu = CTCM_BUFSIZE_DEFAULT - LL_HEADER_LENGTH - 2;
1138		dev->netdev_ops = &ctcm_netdev_ops;
1139		dev->hard_header_len = LL_HEADER_LENGTH + 2;
1140	}
1141
1142	CTCMY_DBF_DEV(SETUP, dev, "finished");
1143
1144	return dev;
1145}
1146
1147/**
1148 * Main IRQ handler.
1149 *
1150 *  cdev	The ccw_device the interrupt is for.
1151 *  intparm	interruption parameter.
1152 *  irb		interruption response block.
1153 */
1154static void ctcm_irq_handler(struct ccw_device *cdev,
1155				unsigned long intparm, struct irb *irb)
1156{
1157	struct channel		*ch;
1158	struct net_device	*dev;
1159	struct ctcm_priv	*priv;
1160	struct ccwgroup_device	*cgdev;
1161	int cstat;
1162	int dstat;
1163
1164	CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
1165		"Enter %s(%s)", CTCM_FUNTAIL, dev_name(&cdev->dev));
1166
1167	if (ctcm_check_irb_error(cdev, irb))
1168		return;
1169
1170	cgdev = dev_get_drvdata(&cdev->dev);
1171
1172	cstat = irb->scsw.cmd.cstat;
1173	dstat = irb->scsw.cmd.dstat;
1174
1175	/* Check for unsolicited interrupts. */
1176	if (cgdev == NULL) {
1177		CTCM_DBF_TEXT_(TRACE, CTC_DBF_ERROR,
1178			"%s(%s) unsolicited irq: c-%02x d-%02x\n",
1179			CTCM_FUNTAIL, dev_name(&cdev->dev), cstat, dstat);
1180		dev_warn(&cdev->dev,
1181			"The adapter received a non-specific IRQ\n");
1182		return;
1183	}
1184
1185	priv = dev_get_drvdata(&cgdev->dev);
1186
1187	/* Try to extract channel from driver data. */
1188	if (priv->channel[CTCM_READ]->cdev == cdev)
1189		ch = priv->channel[CTCM_READ];
1190	else if (priv->channel[CTCM_WRITE]->cdev == cdev)
1191		ch = priv->channel[CTCM_WRITE];
1192	else {
1193		dev_err(&cdev->dev,
1194			"%s: Internal error: Can't determine channel for "
1195			"interrupt device %s\n",
1196			__func__, dev_name(&cdev->dev));
1197			/* Explain: inconsistent internal structures */
1198		return;
1199	}
1200
1201	dev = ch->netdev;
1202	if (dev == NULL) {
1203		dev_err(&cdev->dev,
1204			"%s Internal error: net_device is NULL, ch = 0x%p\n",
1205			__func__, ch);
1206			/* Explain: inconsistent internal structures */
1207		return;
1208	}
1209
1210	/* Copy interruption response block. */
1211	memcpy(ch->irb, irb, sizeof(struct irb));
1212
1213	/* Issue error message and return on subchannel error code */
1214	if (irb->scsw.cmd.cstat) {
1215		fsm_event(ch->fsm, CTC_EVENT_SC_UNKNOWN, ch);
1216		CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1217			"%s(%s): sub-ch check %s: cs=%02x ds=%02x",
1218				CTCM_FUNTAIL, dev->name, ch->id, cstat, dstat);
1219		dev_warn(&cdev->dev,
1220				"A check occurred on the subchannel\n");
1221		return;
1222	}
1223
1224	/* Check the reason-code of a unit check */
1225	if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) {
1226		if ((irb->ecw[0] & ch->sense_rc) == 0)
1227			/* print it only once */
1228			CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1229				"%s(%s): sense=%02x, ds=%02x",
1230				CTCM_FUNTAIL, ch->id, irb->ecw[0], dstat);
1231		ccw_unit_check(ch, irb->ecw[0]);
1232		return;
1233	}
1234	if (irb->scsw.cmd.dstat & DEV_STAT_BUSY) {
1235		if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
1236			fsm_event(ch->fsm, CTC_EVENT_ATTNBUSY, ch);
1237		else
1238			fsm_event(ch->fsm, CTC_EVENT_BUSY, ch);
1239		return;
1240	}
1241	if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
1242		fsm_event(ch->fsm, CTC_EVENT_ATTN, ch);
1243		return;
1244	}
1245	if ((irb->scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS) ||
1246	    (irb->scsw.cmd.stctl == SCSW_STCTL_STATUS_PEND) ||
1247	    (irb->scsw.cmd.stctl ==
1248	     (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)))
1249		fsm_event(ch->fsm, CTC_EVENT_FINSTAT, ch);
1250	else
1251		fsm_event(ch->fsm, CTC_EVENT_IRQ, ch);
1252
1253}
1254
1255static const struct device_type ctcm_devtype = {
1256	.name = "ctcm",
1257	.groups = ctcm_attr_groups,
1258};
1259
1260/**
1261 * Add ctcm specific attributes.
1262 * Add ctcm private data.
1263 *
1264 *  cgdev	pointer to ccwgroup_device just added
1265 *
1266 * returns 0 on success, !0 on failure.
1267 */
1268static int ctcm_probe_device(struct ccwgroup_device *cgdev)
1269{
1270	struct ctcm_priv *priv;
1271
1272	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1273			"%s %p",
1274			__func__, cgdev);
1275
1276	if (!get_device(&cgdev->dev))
1277		return -ENODEV;
1278
1279	priv = kzalloc(sizeof(struct ctcm_priv), GFP_KERNEL);
1280	if (!priv) {
1281		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
1282			"%s: memory allocation failure",
1283			CTCM_FUNTAIL);
1284		put_device(&cgdev->dev);
1285		return -ENOMEM;
1286	}
1287	priv->buffer_size = CTCM_BUFSIZE_DEFAULT;
1288	cgdev->cdev[0]->handler = ctcm_irq_handler;
1289	cgdev->cdev[1]->handler = ctcm_irq_handler;
1290	dev_set_drvdata(&cgdev->dev, priv);
1291	cgdev->dev.type = &ctcm_devtype;
1292
1293	return 0;
1294}
1295
1296/**
1297 * Add a new channel to the list of channels.
1298 * Keeps the channel list sorted.
1299 *
1300 *  cdev	The ccw_device to be added.
1301 *  type	The type class of the new channel.
1302 *  priv	Points to the private data of the ccwgroup_device.
1303 *
1304 * returns 0 on success, !0 on error.
1305 */
1306static int add_channel(struct ccw_device *cdev, enum ctcm_channel_types type,
1307				struct ctcm_priv *priv)
1308{
1309	struct channel **c = &channels;
1310	struct channel *ch;
1311	int ccw_num;
1312	int rc = 0;
1313
1314	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1315		"%s(%s), type %d, proto %d",
1316			__func__, dev_name(&cdev->dev),	type, priv->protocol);
1317
1318	ch = kzalloc(sizeof(struct channel), GFP_KERNEL);
1319	if (ch == NULL)
1320		return -ENOMEM;
1321
1322	ch->protocol = priv->protocol;
1323	if (IS_MPC(priv)) {
1324		ch->discontact_th = kzalloc(TH_HEADER_LENGTH, GFP_KERNEL);
1325		if (ch->discontact_th == NULL)
1326					goto nomem_return;
1327
1328		ch->discontact_th->th_blk_flag = TH_DISCONTACT;
1329		tasklet_init(&ch->ch_disc_tasklet,
1330			mpc_action_send_discontact, (unsigned long)ch);
1331
1332		tasklet_init(&ch->ch_tasklet, ctcmpc_bh, (unsigned long)ch);
1333		ch->max_bufsize = (MPC_BUFSIZE_DEFAULT - 35);
1334		ccw_num = 17;
1335	} else
1336		ccw_num = 8;
1337
1338	ch->ccw = kcalloc(ccw_num, sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
1339	if (ch->ccw == NULL)
1340					goto nomem_return;
1341
1342	ch->cdev = cdev;
1343	snprintf(ch->id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev->dev));
1344	ch->type = type;
1345
1346	/**
1347	 * "static" ccws are used in the following way:
1348	 *
1349	 * ccw[0..2] (Channel program for generic I/O):
1350	 *           0: prepare
1351	 *           1: read or write (depending on direction) with fixed
1352	 *              buffer (idal allocated once when buffer is allocated)
1353	 *           2: nop
1354	 * ccw[3..5] (Channel program for direct write of packets)
1355	 *           3: prepare
1356	 *           4: write (idal allocated on every write).
1357	 *           5: nop
1358	 * ccw[6..7] (Channel program for initial channel setup):
1359	 *           6: set extended mode
1360	 *           7: nop
1361	 *
1362	 * ch->ccw[0..5] are initialized in ch_action_start because
1363	 * the channel's direction is yet unknown here.
1364	 *
1365	 * ccws used for xid2 negotiations
1366	 *  ch-ccw[8-14] need to be used for the XID exchange either
1367	 *    X side XID2 Processing
1368	 *       8:  write control
1369	 *       9:  write th
1370	 *	     10: write XID
1371	 *	     11: read th from secondary
1372	 *	     12: read XID   from secondary
1373	 *	     13: read 4 byte ID
1374	 *	     14: nop
1375	 *    Y side XID Processing
1376	 *	     8:  sense
1377	 *       9:  read th
1378	 *	     10: read XID
1379	 *	     11: write th
1380	 *	     12: write XID
1381	 *	     13: write 4 byte ID
1382	 *	     14: nop
1383	 *
1384	 *  ccws used for double noop due to VM timing issues
1385	 *  which result in unrecoverable Busy on channel
1386	 *       15: nop
1387	 *       16: nop
1388	 */
1389	ch->ccw[6].cmd_code	= CCW_CMD_SET_EXTENDED;
1390	ch->ccw[6].flags	= CCW_FLAG_SLI;
1391
1392	ch->ccw[7].cmd_code	= CCW_CMD_NOOP;
1393	ch->ccw[7].flags	= CCW_FLAG_SLI;
1394
1395	if (IS_MPC(priv)) {
1396		ch->ccw[15].cmd_code = CCW_CMD_WRITE;
1397		ch->ccw[15].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
1398		ch->ccw[15].count    = TH_HEADER_LENGTH;
1399		ch->ccw[15].cda      = virt_to_phys(ch->discontact_th);
1400
1401		ch->ccw[16].cmd_code = CCW_CMD_NOOP;
1402		ch->ccw[16].flags    = CCW_FLAG_SLI;
1403
1404		ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1405				ctc_ch_event_names, CTC_MPC_NR_STATES,
1406				CTC_MPC_NR_EVENTS, ctcmpc_ch_fsm,
1407				mpc_ch_fsm_len, GFP_KERNEL);
1408	} else {
1409		ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1410				ctc_ch_event_names, CTC_NR_STATES,
1411				CTC_NR_EVENTS, ch_fsm,
1412				ch_fsm_len, GFP_KERNEL);
1413	}
1414	if (ch->fsm == NULL)
1415				goto nomem_return;
1416
1417	fsm_newstate(ch->fsm, CTC_STATE_IDLE);
1418
1419	ch->irb = kzalloc(sizeof(struct irb), GFP_KERNEL);
1420	if (ch->irb == NULL)
1421				goto nomem_return;
1422
1423	while (*c && ctcm_less_than((*c)->id, ch->id))
1424		c = &(*c)->next;
1425
1426	if (*c && (!strncmp((*c)->id, ch->id, CTCM_ID_SIZE))) {
1427		CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1428				"%s (%s) already in list, using old entry",
1429				__func__, (*c)->id);
1430
1431				goto free_return;
1432	}
1433
1434	spin_lock_init(&ch->collect_lock);
1435
1436	fsm_settimer(ch->fsm, &ch->timer);
1437	skb_queue_head_init(&ch->io_queue);
1438	skb_queue_head_init(&ch->collect_queue);
1439
1440	if (IS_MPC(priv)) {
1441		fsm_settimer(ch->fsm, &ch->sweep_timer);
1442		skb_queue_head_init(&ch->sweep_queue);
1443	}
1444	ch->next = *c;
1445	*c = ch;
1446	return 0;
1447
1448nomem_return:
1449	rc = -ENOMEM;
1450
1451free_return:	/* note that all channel pointers are 0 or valid */
1452	kfree(ch->ccw);
1453	kfree(ch->discontact_th);
1454	kfree_fsm(ch->fsm);
1455	kfree(ch->irb);
1456	kfree(ch);
1457	return rc;
1458}
1459
1460/*
1461 * Return type of a detected device.
1462 */
1463static enum ctcm_channel_types get_channel_type(struct ccw_device_id *id)
1464{
1465	enum ctcm_channel_types type;
1466	type = (enum ctcm_channel_types)id->driver_info;
1467
1468	if (type == ctcm_channel_type_ficon)
1469		type = ctcm_channel_type_escon;
1470
1471	return type;
1472}
1473
1474/**
1475 *
1476 * Setup an interface.
1477 *
1478 *  cgdev	Device to be setup.
1479 *
1480 * returns 0 on success, !0 on failure.
1481 */
1482static int ctcm_new_device(struct ccwgroup_device *cgdev)
1483{
1484	char read_id[CTCM_ID_SIZE];
1485	char write_id[CTCM_ID_SIZE];
1486	int direction;
1487	enum ctcm_channel_types type;
1488	struct ctcm_priv *priv;
1489	struct net_device *dev;
1490	struct ccw_device *cdev0;
1491	struct ccw_device *cdev1;
1492	struct channel *readc;
1493	struct channel *writec;
1494	int ret;
1495	int result;
1496
1497	priv = dev_get_drvdata(&cgdev->dev);
1498	if (!priv) {
1499		result = -ENODEV;
1500		goto out_err_result;
1501	}
1502
1503	cdev0 = cgdev->cdev[0];
1504	cdev1 = cgdev->cdev[1];
1505
1506	type = get_channel_type(&cdev0->id);
1507
1508	snprintf(read_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev0->dev));
1509	snprintf(write_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev1->dev));
1510
1511	ret = add_channel(cdev0, type, priv);
1512	if (ret) {
1513		result = ret;
1514		goto out_err_result;
1515	}
1516	ret = add_channel(cdev1, type, priv);
1517	if (ret) {
1518		result = ret;
1519		goto out_remove_channel1;
1520	}
1521
1522	ret = ccw_device_set_online(cdev0);
1523	if (ret != 0) {
1524		CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1525			"%s(%s) set_online rc=%d",
1526				CTCM_FUNTAIL, read_id, ret);
1527		result = -EIO;
1528		goto out_remove_channel2;
1529	}
1530
1531	ret = ccw_device_set_online(cdev1);
1532	if (ret != 0) {
1533		CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1534			"%s(%s) set_online rc=%d",
1535				CTCM_FUNTAIL, write_id, ret);
1536
1537		result = -EIO;
1538		goto out_ccw1;
1539	}
1540
1541	dev = ctcm_init_netdevice(priv);
1542	if (dev == NULL) {
1543		result = -ENODEV;
1544		goto out_ccw2;
1545	}
1546
1547	for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1548		priv->channel[direction] =
1549			channel_get(type, direction == CTCM_READ ?
1550				read_id : write_id, direction);
1551		if (priv->channel[direction] == NULL) {
1552			if (direction == CTCM_WRITE)
1553				channel_free(priv->channel[CTCM_READ]);
1554			result = -ENODEV;
1555			goto out_dev;
1556		}
1557		priv->channel[direction]->netdev = dev;
1558		priv->channel[direction]->protocol = priv->protocol;
1559		priv->channel[direction]->max_bufsize = priv->buffer_size;
1560	}
1561	/* sysfs magic */
1562	SET_NETDEV_DEV(dev, &cgdev->dev);
1563
1564	if (register_netdev(dev)) {
1565		result = -ENODEV;
1566		goto out_dev;
1567	}
1568
1569	strlcpy(priv->fsm->name, dev->name, sizeof(priv->fsm->name));
1570
1571	dev_info(&dev->dev,
1572		"setup OK : r/w = %s/%s, protocol : %d\n",
1573			priv->channel[CTCM_READ]->id,
1574			priv->channel[CTCM_WRITE]->id, priv->protocol);
1575
1576	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1577		"setup(%s) OK : r/w = %s/%s, protocol : %d", dev->name,
1578			priv->channel[CTCM_READ]->id,
1579			priv->channel[CTCM_WRITE]->id, priv->protocol);
1580
1581	return 0;
1582out_dev:
1583	ctcm_free_netdevice(dev);
1584out_ccw2:
1585	ccw_device_set_offline(cgdev->cdev[1]);
1586out_ccw1:
1587	ccw_device_set_offline(cgdev->cdev[0]);
1588out_remove_channel2:
1589	readc = channel_get(type, read_id, CTCM_READ);
1590	channel_remove(readc);
1591out_remove_channel1:
1592	writec = channel_get(type, write_id, CTCM_WRITE);
1593	channel_remove(writec);
1594out_err_result:
1595	return result;
1596}
1597
1598/**
1599 * Shutdown an interface.
1600 *
1601 *  cgdev	Device to be shut down.
1602 *
1603 * returns 0 on success, !0 on failure.
1604 */
1605static int ctcm_shutdown_device(struct ccwgroup_device *cgdev)
1606{
1607	struct ctcm_priv *priv;
1608	struct net_device *dev;
1609
1610	priv = dev_get_drvdata(&cgdev->dev);
1611	if (!priv)
1612		return -ENODEV;
1613
1614	if (priv->channel[CTCM_READ]) {
1615		dev = priv->channel[CTCM_READ]->netdev;
1616		CTCM_DBF_DEV(SETUP, dev, "");
1617		/* Close the device */
1618		ctcm_close(dev);
1619		dev->flags &= ~IFF_RUNNING;
1620		channel_free(priv->channel[CTCM_READ]);
1621	} else
1622		dev = NULL;
1623
1624	if (priv->channel[CTCM_WRITE])
1625		channel_free(priv->channel[CTCM_WRITE]);
1626
1627	if (dev) {
1628		unregister_netdev(dev);
1629		ctcm_free_netdevice(dev);
1630	}
1631
1632	if (priv->fsm)
1633		kfree_fsm(priv->fsm);
1634
1635	ccw_device_set_offline(cgdev->cdev[1]);
1636	ccw_device_set_offline(cgdev->cdev[0]);
1637	channel_remove(priv->channel[CTCM_READ]);
1638	channel_remove(priv->channel[CTCM_WRITE]);
1639	priv->channel[CTCM_READ] = priv->channel[CTCM_WRITE] = NULL;
1640
1641	return 0;
1642
1643}
1644
1645
1646static void ctcm_remove_device(struct ccwgroup_device *cgdev)
1647{
1648	struct ctcm_priv *priv = dev_get_drvdata(&cgdev->dev);
1649
1650	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1651			"removing device %p, proto : %d",
1652			cgdev, priv->protocol);
1653
1654	if (cgdev->state == CCWGROUP_ONLINE)
1655		ctcm_shutdown_device(cgdev);
1656	dev_set_drvdata(&cgdev->dev, NULL);
1657	kfree(priv);
1658	put_device(&cgdev->dev);
1659}
1660
1661static struct ccw_device_id ctcm_ids[] = {
1662	{CCW_DEVICE(0x3088, 0x08), .driver_info = ctcm_channel_type_parallel},
1663	{CCW_DEVICE(0x3088, 0x1e), .driver_info = ctcm_channel_type_ficon},
1664	{CCW_DEVICE(0x3088, 0x1f), .driver_info = ctcm_channel_type_escon},
1665	{},
1666};
1667MODULE_DEVICE_TABLE(ccw, ctcm_ids);
1668
1669static struct ccw_driver ctcm_ccw_driver = {
1670	.driver = {
1671		.owner	= THIS_MODULE,
1672		.name	= "ctcm",
1673	},
1674	.ids	= ctcm_ids,
1675	.probe	= ccwgroup_probe_ccwdev,
1676	.remove	= ccwgroup_remove_ccwdev,
1677	.int_class = IRQIO_CTC,
1678};
1679
1680static struct ccwgroup_driver ctcm_group_driver = {
1681	.driver = {
1682		.owner	= THIS_MODULE,
1683		.name	= CTC_DRIVER_NAME,
1684	},
1685	.ccw_driver  = &ctcm_ccw_driver,
1686	.setup	     = ctcm_probe_device,
1687	.remove      = ctcm_remove_device,
1688	.set_online  = ctcm_new_device,
1689	.set_offline = ctcm_shutdown_device,
1690};
1691
1692static ssize_t group_store(struct device_driver *ddrv, const char *buf,
1693			   size_t count)
1694{
1695	int err;
1696
1697	err = ccwgroup_create_dev(ctcm_root_dev, &ctcm_group_driver, 2, buf);
1698	return err ? err : count;
1699}
1700static DRIVER_ATTR_WO(group);
1701
1702static struct attribute *ctcm_drv_attrs[] = {
1703	&driver_attr_group.attr,
1704	NULL,
1705};
1706static struct attribute_group ctcm_drv_attr_group = {
1707	.attrs = ctcm_drv_attrs,
1708};
1709static const struct attribute_group *ctcm_drv_attr_groups[] = {
1710	&ctcm_drv_attr_group,
1711	NULL,
1712};
1713
1714/*
1715 * Module related routines
1716 */
1717
1718/*
1719 * Prepare to be unloaded. Free IRQ's and release all resources.
1720 * This is called just before this module is unloaded. It is
1721 * not called, if the usage count is !0, so we don't need to check
1722 * for that.
1723 */
1724static void __exit ctcm_exit(void)
1725{
1726	ccwgroup_driver_unregister(&ctcm_group_driver);
1727	ccw_driver_unregister(&ctcm_ccw_driver);
1728	root_device_unregister(ctcm_root_dev);
1729	ctcm_unregister_dbf_views();
1730	pr_info("CTCM driver unloaded\n");
1731}
1732
1733/*
1734 * Print Banner.
1735 */
1736static void print_banner(void)
1737{
1738	pr_info("CTCM driver initialized\n");
1739}
1740
1741/**
1742 * Initialize module.
1743 * This is called just after the module is loaded.
1744 *
1745 * returns 0 on success, !0 on error.
1746 */
1747static int __init ctcm_init(void)
1748{
1749	int ret;
1750
1751	channels = NULL;
1752
1753	ret = ctcm_register_dbf_views();
1754	if (ret)
1755		goto out_err;
1756	ctcm_root_dev = root_device_register("ctcm");
1757	ret = PTR_ERR_OR_ZERO(ctcm_root_dev);
1758	if (ret)
1759		goto register_err;
1760	ret = ccw_driver_register(&ctcm_ccw_driver);
1761	if (ret)
1762		goto ccw_err;
1763	ctcm_group_driver.driver.groups = ctcm_drv_attr_groups;
1764	ret = ccwgroup_driver_register(&ctcm_group_driver);
1765	if (ret)
1766		goto ccwgroup_err;
1767	print_banner();
1768	return 0;
1769
1770ccwgroup_err:
1771	ccw_driver_unregister(&ctcm_ccw_driver);
1772ccw_err:
1773	root_device_unregister(ctcm_root_dev);
1774register_err:
1775	ctcm_unregister_dbf_views();
1776out_err:
1777	pr_err("%s / Initializing the ctcm device driver failed, ret = %d\n",
1778		__func__, ret);
1779	return ret;
1780}
1781
1782module_init(ctcm_init);
1783module_exit(ctcm_exit);
1784
1785MODULE_AUTHOR("Peter Tiedemann <ptiedem@de.ibm.com>");
1786MODULE_DESCRIPTION("Network driver for S/390 CTC + CTCMPC (SNA)");
1787MODULE_LICENSE("GPL");
1788