xref: /linux/drivers/s390/net/ctcm_main.c (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
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 pr_fmt(fmt) "ctcm: " fmt
24 
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <linux/slab.h>
29 #include <linux/errno.h>
30 #include <linux/types.h>
31 #include <linux/interrupt.h>
32 #include <linux/timer.h>
33 #include <linux/bitops.h>
34 
35 #include <linux/signal.h>
36 #include <linux/string.h>
37 
38 #include <linux/ip.h>
39 #include <linux/if_arp.h>
40 #include <linux/tcp.h>
41 #include <linux/skbuff.h>
42 #include <linux/ctype.h>
43 #include <net/dst.h>
44 
45 #include <linux/io.h>
46 #include <asm/ccwdev.h>
47 #include <asm/ccwgroup.h>
48 #include <linux/uaccess.h>
49 
50 #include <asm/idals.h>
51 
52 #include "ctcm_fsms.h"
53 #include "ctcm_main.h"
54 
55 /* Some common global variables */
56 
57 /*
58  * The root device for ctcm group devices
59  */
60 static struct device *ctcm_root_dev;
61 
62 /*
63  * Linked list of all detected channels.
64  */
65 struct channel *channels;
66 
67 /*
68  * Unpack a just received skb and hand it over to
69  * upper layers.
70  *
71  *  ch		The channel where this skb has been received.
72  *  pskb	The received skb.
73  */
74 void ctcm_unpack_skb(struct channel *ch, struct sk_buff *pskb)
75 {
76 	struct net_device *dev = ch->netdev;
77 	struct ctcm_priv *priv = dev->ml_priv;
78 	__u16 len = *((__u16 *) pskb->data);
79 
80 	skb_put(pskb, 2 + LL_HEADER_LENGTH);
81 	skb_pull(pskb, 2);
82 	pskb->dev = dev;
83 	pskb->ip_summed = CHECKSUM_UNNECESSARY;
84 	while (len > 0) {
85 		struct sk_buff *skb;
86 		int skblen;
87 		struct ll_header *header = (struct ll_header *)pskb->data;
88 
89 		skb_pull(pskb, LL_HEADER_LENGTH);
90 		if ((ch->protocol == CTCM_PROTO_S390) &&
91 		    (header->type != ETH_P_IP)) {
92 			if (!(ch->logflags & LOG_FLAG_ILLEGALPKT)) {
93 				ch->logflags |= LOG_FLAG_ILLEGALPKT;
94 				/*
95 				 * Check packet type only if we stick strictly
96 				 * to S/390's protocol of OS390. This only
97 				 * supports IP. Otherwise allow any packet
98 				 * type.
99 				 */
100 				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
101 					"%s(%s): Illegal packet type 0x%04x"
102 					" - dropping",
103 					CTCM_FUNTAIL, dev->name, header->type);
104 			}
105 			priv->stats.rx_dropped++;
106 			priv->stats.rx_frame_errors++;
107 			return;
108 		}
109 		pskb->protocol = cpu_to_be16(header->type);
110 		if ((header->length <= LL_HEADER_LENGTH) ||
111 		    (len <= LL_HEADER_LENGTH)) {
112 			if (!(ch->logflags & LOG_FLAG_ILLEGALSIZE)) {
113 				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
114 					"%s(%s): Illegal packet size %d(%d,%d)"
115 					"- dropping",
116 					CTCM_FUNTAIL, dev->name,
117 					header->length, dev->mtu, len);
118 				ch->logflags |= LOG_FLAG_ILLEGALSIZE;
119 			}
120 
121 			priv->stats.rx_dropped++;
122 			priv->stats.rx_length_errors++;
123 			return;
124 		}
125 		header->length -= LL_HEADER_LENGTH;
126 		len -= LL_HEADER_LENGTH;
127 		if ((header->length > skb_tailroom(pskb)) ||
128 		    (header->length > len)) {
129 			if (!(ch->logflags & LOG_FLAG_OVERRUN)) {
130 				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
131 					"%s(%s): Packet size %d (overrun)"
132 					" - dropping", CTCM_FUNTAIL,
133 						dev->name, header->length);
134 				ch->logflags |= LOG_FLAG_OVERRUN;
135 			}
136 
137 			priv->stats.rx_dropped++;
138 			priv->stats.rx_length_errors++;
139 			return;
140 		}
141 		skb_put(pskb, header->length);
142 		skb_reset_mac_header(pskb);
143 		len -= header->length;
144 		skb = dev_alloc_skb(pskb->len);
145 		if (!skb) {
146 			if (!(ch->logflags & LOG_FLAG_NOMEM)) {
147 				CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
148 					"%s(%s): MEMORY allocation error",
149 						CTCM_FUNTAIL, dev->name);
150 				ch->logflags |= LOG_FLAG_NOMEM;
151 			}
152 			priv->stats.rx_dropped++;
153 			return;
154 		}
155 		skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
156 					  pskb->len);
157 		skb_reset_mac_header(skb);
158 		skb->dev = pskb->dev;
159 		skb->protocol = pskb->protocol;
160 		pskb->ip_summed = CHECKSUM_UNNECESSARY;
161 		skblen = skb->len;
162 		/*
163 		 * reset logflags
164 		 */
165 		ch->logflags = 0;
166 		priv->stats.rx_packets++;
167 		priv->stats.rx_bytes += skblen;
168 		netif_rx(skb);
169 		if (len > 0) {
170 			skb_pull(pskb, header->length);
171 			if (skb_tailroom(pskb) < LL_HEADER_LENGTH) {
172 				CTCM_DBF_DEV_NAME(TRACE, dev,
173 					"Overrun in ctcm_unpack_skb");
174 				ch->logflags |= LOG_FLAG_OVERRUN;
175 				return;
176 			}
177 			skb_put(pskb, LL_HEADER_LENGTH);
178 		}
179 	}
180 }
181 
182 /*
183  * Release a specific channel in the channel list.
184  *
185  *  ch		Pointer to channel struct to be released.
186  */
187 static void channel_free(struct channel *ch)
188 {
189 	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s)", CTCM_FUNTAIL, ch->id);
190 	ch->flags &= ~CHANNEL_FLAGS_INUSE;
191 	fsm_newstate(ch->fsm, CTC_STATE_IDLE);
192 }
193 
194 /*
195  * Remove a specific channel in the channel list.
196  *
197  *  ch		Pointer to channel struct to be released.
198  */
199 static void channel_remove(struct channel *ch)
200 {
201 	struct channel **c = &channels;
202 	char chid[CTCM_ID_SIZE];
203 	int ok = 0;
204 
205 	if (ch == NULL)
206 		return;
207 	else
208 		strscpy(chid, ch->id, sizeof(chid));
209 
210 	channel_free(ch);
211 	while (*c) {
212 		if (*c == ch) {
213 			*c = ch->next;
214 			fsm_deltimer(&ch->timer);
215 			if (IS_MPC(ch))
216 				fsm_deltimer(&ch->sweep_timer);
217 
218 			kfree_fsm(ch->fsm);
219 			clear_normalized_cda(&ch->ccw[4]);
220 			if (ch->trans_skb != NULL) {
221 				clear_normalized_cda(&ch->ccw[1]);
222 				dev_kfree_skb_any(ch->trans_skb);
223 			}
224 			if (IS_MPC(ch)) {
225 				tasklet_kill(&ch->ch_tasklet);
226 				tasklet_kill(&ch->ch_disc_tasklet);
227 				kfree(ch->discontact_th);
228 			}
229 			kfree(ch->ccw);
230 			kfree(ch->irb);
231 			kfree(ch);
232 			ok = 1;
233 			break;
234 		}
235 		c = &((*c)->next);
236 	}
237 
238 	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO, "%s(%s) %s", CTCM_FUNTAIL,
239 			chid, ok ? "OK" : "failed");
240 }
241 
242 /*
243  * Get a specific channel from the channel list.
244  *
245  *  type	Type of channel we are interested in.
246  *  id		Id of channel we are interested in.
247  *  direction	Direction we want to use this channel for.
248  *
249  * returns Pointer to a channel or NULL if no matching channel available.
250  */
251 static struct channel *channel_get(enum ctcm_channel_types type,
252 					char *id, int direction)
253 {
254 	struct channel *ch = channels;
255 
256 	while (ch && (strncmp(ch->id, id, CTCM_ID_SIZE) || (ch->type != type)))
257 		ch = ch->next;
258 	if (!ch) {
259 		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
260 				"%s(%d, %s, %d) not found in channel list\n",
261 				CTCM_FUNTAIL, type, id, direction);
262 	} else {
263 		if (ch->flags & CHANNEL_FLAGS_INUSE)
264 			ch = NULL;
265 		else {
266 			ch->flags |= CHANNEL_FLAGS_INUSE;
267 			ch->flags &= ~CHANNEL_FLAGS_RWMASK;
268 			ch->flags |= (direction == CTCM_WRITE)
269 			    ? CHANNEL_FLAGS_WRITE : CHANNEL_FLAGS_READ;
270 			fsm_newstate(ch->fsm, CTC_STATE_STOPPED);
271 		}
272 	}
273 	return ch;
274 }
275 
276 static long ctcm_check_irb_error(struct ccw_device *cdev, struct irb *irb)
277 {
278 	if (!IS_ERR(irb))
279 		return 0;
280 
281 	CTCM_DBF_TEXT_(ERROR, CTC_DBF_WARN,
282 			"irb error %ld on device %s\n",
283 				PTR_ERR(irb), dev_name(&cdev->dev));
284 
285 	switch (PTR_ERR(irb)) {
286 	case -EIO:
287 		dev_err(&cdev->dev,
288 			"An I/O-error occurred on the CTCM device\n");
289 		break;
290 	case -ETIMEDOUT:
291 		dev_err(&cdev->dev,
292 			"An adapter hardware operation timed out\n");
293 		break;
294 	default:
295 		dev_err(&cdev->dev,
296 			"An error occurred on the adapter hardware\n");
297 	}
298 	return PTR_ERR(irb);
299 }
300 
301 
302 /*
303  * Check sense of a unit check.
304  *
305  *  ch		The channel, the sense code belongs to.
306  *  sense	The sense code to inspect.
307  */
308 static void ccw_unit_check(struct channel *ch, __u8 sense)
309 {
310 	CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
311 			"%s(%s): %02x",
312 				CTCM_FUNTAIL, ch->id, sense);
313 
314 	if (sense & SNS0_INTERVENTION_REQ) {
315 		if (sense & 0x01) {
316 			if (ch->sense_rc != 0x01) {
317 				pr_notice(
318 					"%s: The communication peer has "
319 					"disconnected\n", ch->id);
320 				ch->sense_rc = 0x01;
321 			}
322 			fsm_event(ch->fsm, CTC_EVENT_UC_RCRESET, ch);
323 		} else {
324 			if (ch->sense_rc != SNS0_INTERVENTION_REQ) {
325 				pr_notice(
326 					"%s: The remote operating system is "
327 					"not available\n", ch->id);
328 				ch->sense_rc = SNS0_INTERVENTION_REQ;
329 			}
330 			fsm_event(ch->fsm, CTC_EVENT_UC_RSRESET, ch);
331 		}
332 	} else if (sense & SNS0_EQUIPMENT_CHECK) {
333 		if (sense & SNS0_BUS_OUT_CHECK) {
334 			if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
335 				CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
336 					"%s(%s): remote HW error %02x",
337 						CTCM_FUNTAIL, ch->id, sense);
338 				ch->sense_rc = SNS0_BUS_OUT_CHECK;
339 			}
340 			fsm_event(ch->fsm, CTC_EVENT_UC_HWFAIL, ch);
341 		} else {
342 			if (ch->sense_rc != SNS0_EQUIPMENT_CHECK) {
343 				CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
344 					"%s(%s): remote read parity error %02x",
345 						CTCM_FUNTAIL, ch->id, sense);
346 				ch->sense_rc = SNS0_EQUIPMENT_CHECK;
347 			}
348 			fsm_event(ch->fsm, CTC_EVENT_UC_RXPARITY, ch);
349 		}
350 	} else if (sense & SNS0_BUS_OUT_CHECK) {
351 		if (ch->sense_rc != SNS0_BUS_OUT_CHECK) {
352 			CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
353 				"%s(%s): BUS OUT error %02x",
354 					CTCM_FUNTAIL, ch->id, sense);
355 			ch->sense_rc = SNS0_BUS_OUT_CHECK;
356 		}
357 		if (sense & 0x04)	/* data-streaming timeout */
358 			fsm_event(ch->fsm, CTC_EVENT_UC_TXTIMEOUT, ch);
359 		else			/* Data-transfer parity error */
360 			fsm_event(ch->fsm, CTC_EVENT_UC_TXPARITY, ch);
361 	} else if (sense & SNS0_CMD_REJECT) {
362 		if (ch->sense_rc != SNS0_CMD_REJECT) {
363 			CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
364 				"%s(%s): Command rejected",
365 						CTCM_FUNTAIL, ch->id);
366 			ch->sense_rc = SNS0_CMD_REJECT;
367 		}
368 	} else if (sense == 0) {
369 		CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
370 			"%s(%s): Unit check ZERO",
371 					CTCM_FUNTAIL, ch->id);
372 		fsm_event(ch->fsm, CTC_EVENT_UC_ZERO, ch);
373 	} else {
374 		CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
375 			"%s(%s): Unit check code %02x unknown",
376 					CTCM_FUNTAIL, ch->id, sense);
377 		fsm_event(ch->fsm, CTC_EVENT_UC_UNKNOWN, ch);
378 	}
379 }
380 
381 int ctcm_ch_alloc_buffer(struct channel *ch)
382 {
383 	clear_normalized_cda(&ch->ccw[1]);
384 	ch->trans_skb = __dev_alloc_skb(ch->max_bufsize, GFP_ATOMIC | GFP_DMA);
385 	if (ch->trans_skb == NULL) {
386 		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
387 			"%s(%s): %s trans_skb allocation error",
388 			CTCM_FUNTAIL, ch->id,
389 			(CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ?
390 				"RX" : "TX");
391 		return -ENOMEM;
392 	}
393 
394 	ch->ccw[1].count = ch->max_bufsize;
395 	if (set_normalized_cda(&ch->ccw[1], ch->trans_skb->data)) {
396 		dev_kfree_skb(ch->trans_skb);
397 		ch->trans_skb = NULL;
398 		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
399 			"%s(%s): %s set norm_cda failed",
400 			CTCM_FUNTAIL, ch->id,
401 			(CHANNEL_DIRECTION(ch->flags) == CTCM_READ) ?
402 				"RX" : "TX");
403 		return -ENOMEM;
404 	}
405 
406 	ch->ccw[1].count = 0;
407 	ch->trans_skb_data = ch->trans_skb->data;
408 	ch->flags &= ~CHANNEL_FLAGS_BUFSIZE_CHANGED;
409 	return 0;
410 }
411 
412 /*
413  * Interface API for upper network layers
414  */
415 
416 /*
417  * Open an interface.
418  * Called from generic network layer when ifconfig up is run.
419  *
420  *  dev		Pointer to interface struct.
421  *
422  * returns 0 on success, -ERRNO on failure. (Never fails.)
423  */
424 int ctcm_open(struct net_device *dev)
425 {
426 	struct ctcm_priv *priv = dev->ml_priv;
427 
428 	CTCMY_DBF_DEV_NAME(SETUP, dev, "");
429 	if (!IS_MPC(priv))
430 		fsm_event(priv->fsm,	DEV_EVENT_START, dev);
431 	return 0;
432 }
433 
434 /*
435  * Close an interface.
436  * Called from generic network layer when ifconfig down is run.
437  *
438  *  dev		Pointer to interface struct.
439  *
440  * returns 0 on success, -ERRNO on failure. (Never fails.)
441  */
442 int ctcm_close(struct net_device *dev)
443 {
444 	struct ctcm_priv *priv = dev->ml_priv;
445 
446 	CTCMY_DBF_DEV_NAME(SETUP, dev, "");
447 	if (!IS_MPC(priv))
448 		fsm_event(priv->fsm, DEV_EVENT_STOP, dev);
449 	return 0;
450 }
451 
452 
453 /*
454  * Transmit a packet.
455  * This is a helper function for ctcm_tx().
456  *
457  *  ch		Channel to be used for sending.
458  *  skb		Pointer to struct sk_buff of packet to send.
459  *            The linklevel header has already been set up
460  *            by ctcm_tx().
461  *
462  * returns 0 on success, -ERRNO on failure. (Never fails.)
463  */
464 static int ctcm_transmit_skb(struct channel *ch, struct sk_buff *skb)
465 {
466 	unsigned long saveflags;
467 	struct ll_header header;
468 	int rc = 0;
469 	__u16 block_len;
470 	int ccw_idx;
471 	struct sk_buff *nskb;
472 	unsigned long hi;
473 
474 	/* we need to acquire the lock for testing the state
475 	 * otherwise we can have an IRQ changing the state to
476 	 * TXIDLE after the test but before acquiring the lock.
477 	 */
478 	spin_lock_irqsave(&ch->collect_lock, saveflags);
479 	if (fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) {
480 		int l = skb->len + LL_HEADER_LENGTH;
481 
482 		if (ch->collect_len + l > ch->max_bufsize - 2) {
483 			spin_unlock_irqrestore(&ch->collect_lock, saveflags);
484 			return -EBUSY;
485 		} else {
486 			refcount_inc(&skb->users);
487 			header.length = l;
488 			header.type = be16_to_cpu(skb->protocol);
489 			header.unused = 0;
490 			memcpy(skb_push(skb, LL_HEADER_LENGTH), &header,
491 			       LL_HEADER_LENGTH);
492 			skb_queue_tail(&ch->collect_queue, skb);
493 			ch->collect_len += l;
494 		}
495 		spin_unlock_irqrestore(&ch->collect_lock, saveflags);
496 		goto done;
497 	}
498 	spin_unlock_irqrestore(&ch->collect_lock, saveflags);
499 	/*
500 	 * Protect skb against beeing free'd by upper
501 	 * layers.
502 	 */
503 	refcount_inc(&skb->users);
504 	ch->prof.txlen += skb->len;
505 	header.length = skb->len + LL_HEADER_LENGTH;
506 	header.type = be16_to_cpu(skb->protocol);
507 	header.unused = 0;
508 	memcpy(skb_push(skb, LL_HEADER_LENGTH), &header, LL_HEADER_LENGTH);
509 	block_len = skb->len + 2;
510 	*((__u16 *)skb_push(skb, 2)) = block_len;
511 
512 	/*
513 	 * IDAL support in CTCM is broken, so we have to
514 	 * care about skb's above 2G ourselves.
515 	 */
516 	hi = ((unsigned long)skb_tail_pointer(skb) + LL_HEADER_LENGTH) >> 31;
517 	if (hi) {
518 		nskb = alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
519 		if (!nskb) {
520 			refcount_dec(&skb->users);
521 			skb_pull(skb, LL_HEADER_LENGTH + 2);
522 			ctcm_clear_busy(ch->netdev);
523 			return -ENOMEM;
524 		} else {
525 			skb_put_data(nskb, skb->data, skb->len);
526 			refcount_inc(&nskb->users);
527 			refcount_dec(&skb->users);
528 			dev_kfree_skb_irq(skb);
529 			skb = nskb;
530 		}
531 	}
532 
533 	ch->ccw[4].count = block_len;
534 	if (set_normalized_cda(&ch->ccw[4], skb->data)) {
535 		/*
536 		 * idal allocation failed, try via copying to
537 		 * trans_skb. trans_skb usually has a pre-allocated
538 		 * idal.
539 		 */
540 		if (ctcm_checkalloc_buffer(ch)) {
541 			/*
542 			 * Remove our header. It gets added
543 			 * again on retransmit.
544 			 */
545 			refcount_dec(&skb->users);
546 			skb_pull(skb, LL_HEADER_LENGTH + 2);
547 			ctcm_clear_busy(ch->netdev);
548 			return -ENOMEM;
549 		}
550 
551 		skb_reset_tail_pointer(ch->trans_skb);
552 		ch->trans_skb->len = 0;
553 		ch->ccw[1].count = skb->len;
554 		skb_copy_from_linear_data(skb,
555 				skb_put(ch->trans_skb, skb->len), skb->len);
556 		refcount_dec(&skb->users);
557 		dev_kfree_skb_irq(skb);
558 		ccw_idx = 0;
559 	} else {
560 		skb_queue_tail(&ch->io_queue, skb);
561 		ccw_idx = 3;
562 	}
563 	if (do_debug_ccw)
564 		ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
565 					sizeof(struct ccw1) * 3);
566 	ch->retry = 0;
567 	fsm_newstate(ch->fsm, CTC_STATE_TX);
568 	fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
569 	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
570 	ch->prof.send_stamp = jiffies;
571 	rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx], 0, 0xff, 0);
572 	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
573 	if (ccw_idx == 3)
574 		ch->prof.doios_single++;
575 	if (rc != 0) {
576 		fsm_deltimer(&ch->timer);
577 		ctcm_ccw_check_rc(ch, rc, "single skb TX");
578 		if (ccw_idx == 3)
579 			skb_dequeue_tail(&ch->io_queue);
580 		/*
581 		 * Remove our header. It gets added
582 		 * again on retransmit.
583 		 */
584 		skb_pull(skb, LL_HEADER_LENGTH + 2);
585 	} else if (ccw_idx == 0) {
586 		struct net_device *dev = ch->netdev;
587 		struct ctcm_priv *priv = dev->ml_priv;
588 		priv->stats.tx_packets++;
589 		priv->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
590 	}
591 done:
592 	ctcm_clear_busy(ch->netdev);
593 	return rc;
594 }
595 
596 static void ctcmpc_send_sweep_req(struct channel *rch)
597 {
598 	struct net_device *dev = rch->netdev;
599 	struct ctcm_priv *priv;
600 	struct mpc_group *grp;
601 	struct th_sweep *header;
602 	struct sk_buff *sweep_skb;
603 	struct channel *ch;
604 	/* int rc = 0; */
605 
606 	priv = dev->ml_priv;
607 	grp = priv->mpcg;
608 	ch = priv->channel[CTCM_WRITE];
609 
610 	/* sweep processing is not complete until response and request */
611 	/* has completed for all read channels in group		       */
612 	if (grp->in_sweep == 0) {
613 		grp->in_sweep = 1;
614 		grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
615 		grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
616 	}
617 
618 	sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
619 
620 	if (sweep_skb == NULL)	{
621 		/* rc = -ENOMEM; */
622 				goto nomem;
623 	}
624 
625 	header = skb_put_zero(sweep_skb, TH_SWEEP_LENGTH);
626 	header->th.th_ch_flag	= TH_SWEEP_REQ;  /* 0x0f */
627 	header->sw.th_last_seq	= ch->th_seq_num;
628 
629 	netif_trans_update(dev);
630 	skb_queue_tail(&ch->sweep_queue, sweep_skb);
631 
632 	fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
633 
634 	return;
635 
636 nomem:
637 	grp->in_sweep = 0;
638 	ctcm_clear_busy(dev);
639 	fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
640 
641 	return;
642 }
643 
644 /*
645  * MPC mode version of transmit_skb
646  */
647 static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
648 {
649 	struct pdu *p_header;
650 	struct net_device *dev = ch->netdev;
651 	struct ctcm_priv *priv = dev->ml_priv;
652 	struct mpc_group *grp = priv->mpcg;
653 	struct th_header *header;
654 	struct sk_buff *nskb;
655 	int rc = 0;
656 	int ccw_idx;
657 	unsigned long hi;
658 	unsigned long saveflags = 0;	/* avoids compiler warning */
659 
660 	CTCM_PR_DEBUG("Enter %s: %s, cp=%i ch=0x%p id=%s state=%s\n",
661 			__func__, dev->name, smp_processor_id(), ch,
662 					ch->id, fsm_getstate_str(ch->fsm));
663 
664 	if ((fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) || grp->in_sweep) {
665 		spin_lock_irqsave(&ch->collect_lock, saveflags);
666 		refcount_inc(&skb->users);
667 
668 		p_header = skb_push(skb, PDU_HEADER_LENGTH);
669 		p_header->pdu_offset = skb->len - PDU_HEADER_LENGTH;
670 		p_header->pdu_proto = 0x01;
671 		if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
672 			p_header->pdu_flag = PDU_FIRST | PDU_CNTL;
673 		} else {
674 			p_header->pdu_flag = PDU_FIRST;
675 		}
676 		p_header->pdu_seq = 0;
677 
678 		CTCM_PR_DEBUG("%s(%s): Put on collect_q - skb len: %04x \n"
679 				"pdu header and data for up to 32 bytes:\n",
680 				__func__, dev->name, skb->len);
681 		CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
682 
683 		skb_queue_tail(&ch->collect_queue, skb);
684 		ch->collect_len += skb->len;
685 
686 		spin_unlock_irqrestore(&ch->collect_lock, saveflags);
687 		goto done;
688 	}
689 
690 	/*
691 	 * Protect skb against beeing free'd by upper
692 	 * layers.
693 	 */
694 	refcount_inc(&skb->users);
695 
696 	/*
697 	 * IDAL support in CTCM is broken, so we have to
698 	 * care about skb's above 2G ourselves.
699 	 */
700 	hi = ((unsigned long)skb->tail + TH_HEADER_LENGTH) >> 31;
701 	if (hi) {
702 		nskb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
703 		if (!nskb) {
704 			goto nomem_exit;
705 		} else {
706 			skb_put_data(nskb, skb->data, skb->len);
707 			refcount_inc(&nskb->users);
708 			refcount_dec(&skb->users);
709 			dev_kfree_skb_irq(skb);
710 			skb = nskb;
711 		}
712 	}
713 
714 	p_header = skb_push(skb, PDU_HEADER_LENGTH);
715 	p_header->pdu_offset = skb->len - PDU_HEADER_LENGTH;
716 	p_header->pdu_proto = 0x01;
717 	p_header->pdu_seq = 0;
718 	if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
719 		p_header->pdu_flag = PDU_FIRST | PDU_CNTL;
720 	} else {
721 		p_header->pdu_flag = PDU_FIRST;
722 	}
723 
724 	if (ch->collect_len > 0) {
725 		spin_lock_irqsave(&ch->collect_lock, saveflags);
726 		skb_queue_tail(&ch->collect_queue, skb);
727 		ch->collect_len += skb->len;
728 		skb = skb_dequeue(&ch->collect_queue);
729 		ch->collect_len -= skb->len;
730 		spin_unlock_irqrestore(&ch->collect_lock, saveflags);
731 	}
732 
733 	p_header = (struct pdu *)skb->data;
734 	p_header->pdu_flag |= PDU_LAST;
735 
736 	ch->prof.txlen += skb->len - PDU_HEADER_LENGTH;
737 
738 	/* put the TH on the packet */
739 	header = skb_push(skb, TH_HEADER_LENGTH);
740 	memset(header, 0, TH_HEADER_LENGTH);
741 
742 	header->th_ch_flag = TH_HAS_PDU;  /* Normal data */
743 	ch->th_seq_num++;
744 	header->th_seq_num = ch->th_seq_num;
745 
746 	CTCM_PR_DBGDATA("%s(%s) ToVTAM_th_seq= %08x\n" ,
747 		       __func__, dev->name, ch->th_seq_num);
748 
749 	CTCM_PR_DBGDATA("%s(%s): skb len: %04x\n - pdu header and data for "
750 			"up to 32 bytes sent to vtam:\n",
751 				__func__, dev->name, skb->len);
752 	CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
753 
754 	ch->ccw[4].count = skb->len;
755 	if (set_normalized_cda(&ch->ccw[4], skb->data)) {
756 		/*
757 		 * idal allocation failed, try via copying to trans_skb.
758 		 * trans_skb usually has a pre-allocated idal.
759 		 */
760 		if (ctcm_checkalloc_buffer(ch)) {
761 			/*
762 			 * Remove our header.
763 			 * It gets added again on retransmit.
764 			 */
765 				goto nomem_exit;
766 		}
767 
768 		skb_reset_tail_pointer(ch->trans_skb);
769 		ch->trans_skb->len = 0;
770 		ch->ccw[1].count = skb->len;
771 		skb_put_data(ch->trans_skb, skb->data, skb->len);
772 		refcount_dec(&skb->users);
773 		dev_kfree_skb_irq(skb);
774 		ccw_idx = 0;
775 		CTCM_PR_DBGDATA("%s(%s): trans_skb len: %04x\n"
776 				"up to 32 bytes sent to vtam:\n",
777 				__func__, dev->name, ch->trans_skb->len);
778 		CTCM_D3_DUMP((char *)ch->trans_skb->data,
779 				min_t(int, 32, ch->trans_skb->len));
780 	} else {
781 		skb_queue_tail(&ch->io_queue, skb);
782 		ccw_idx = 3;
783 	}
784 	ch->retry = 0;
785 	fsm_newstate(ch->fsm, CTC_STATE_TX);
786 	fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
787 
788 	if (do_debug_ccw)
789 		ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
790 					sizeof(struct ccw1) * 3);
791 
792 	spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
793 	ch->prof.send_stamp = jiffies;
794 	rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx], 0, 0xff, 0);
795 	spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
796 	if (ccw_idx == 3)
797 		ch->prof.doios_single++;
798 	if (rc != 0) {
799 		fsm_deltimer(&ch->timer);
800 		ctcm_ccw_check_rc(ch, rc, "single skb TX");
801 		if (ccw_idx == 3)
802 			skb_dequeue_tail(&ch->io_queue);
803 	} else if (ccw_idx == 0) {
804 		priv->stats.tx_packets++;
805 		priv->stats.tx_bytes += skb->len - TH_HEADER_LENGTH;
806 	}
807 	if (ch->th_seq_num > 0xf0000000)	/* Chose at random. */
808 		ctcmpc_send_sweep_req(ch);
809 
810 	goto done;
811 nomem_exit:
812 	CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_CRIT,
813 			"%s(%s): MEMORY allocation ERROR\n",
814 			CTCM_FUNTAIL, ch->id);
815 	rc = -ENOMEM;
816 	refcount_dec(&skb->users);
817 	dev_kfree_skb_any(skb);
818 	fsm_event(priv->mpcg->fsm, MPCG_EVENT_INOP, dev);
819 done:
820 	CTCM_PR_DEBUG("Exit %s(%s)\n", __func__, dev->name);
821 	return rc;
822 }
823 
824 /*
825  * Start transmission of a packet.
826  * Called from generic network device layer.
827  */
828 /* first merge version - leaving both functions separated */
829 static netdev_tx_t ctcm_tx(struct sk_buff *skb, struct net_device *dev)
830 {
831 	struct ctcm_priv *priv = dev->ml_priv;
832 
833 	if (skb == NULL) {
834 		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
835 				"%s(%s): NULL sk_buff passed",
836 					CTCM_FUNTAIL, dev->name);
837 		priv->stats.tx_dropped++;
838 		return NETDEV_TX_OK;
839 	}
840 	if (skb_headroom(skb) < (LL_HEADER_LENGTH + 2)) {
841 		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
842 			"%s(%s): Got sk_buff with head room < %ld bytes",
843 			CTCM_FUNTAIL, dev->name, LL_HEADER_LENGTH + 2);
844 		dev_kfree_skb(skb);
845 		priv->stats.tx_dropped++;
846 		return NETDEV_TX_OK;
847 	}
848 
849 	/*
850 	 * If channels are not running, try to restart them
851 	 * and throw away packet.
852 	 */
853 	if (fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) {
854 		fsm_event(priv->fsm, DEV_EVENT_START, dev);
855 		dev_kfree_skb(skb);
856 		priv->stats.tx_dropped++;
857 		priv->stats.tx_errors++;
858 		priv->stats.tx_carrier_errors++;
859 		return NETDEV_TX_OK;
860 	}
861 
862 	if (ctcm_test_and_set_busy(dev))
863 		return NETDEV_TX_BUSY;
864 
865 	netif_trans_update(dev);
866 	if (ctcm_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0)
867 		return NETDEV_TX_BUSY;
868 	return NETDEV_TX_OK;
869 }
870 
871 /* unmerged MPC variant of ctcm_tx */
872 static netdev_tx_t ctcmpc_tx(struct sk_buff *skb, struct net_device *dev)
873 {
874 	int len = 0;
875 	struct ctcm_priv *priv = dev->ml_priv;
876 	struct mpc_group *grp  = priv->mpcg;
877 	struct sk_buff *newskb = NULL;
878 
879 	/*
880 	 * Some sanity checks ...
881 	 */
882 	if (skb == NULL) {
883 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
884 			"%s(%s): NULL sk_buff passed",
885 					CTCM_FUNTAIL, dev->name);
886 		priv->stats.tx_dropped++;
887 		goto done;
888 	}
889 	if (skb_headroom(skb) < (TH_HEADER_LENGTH + PDU_HEADER_LENGTH)) {
890 		CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
891 			"%s(%s): Got sk_buff with head room < %ld bytes",
892 			CTCM_FUNTAIL, dev->name,
893 				TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
894 
895 		CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
896 
897 		len =  skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
898 		newskb = __dev_alloc_skb(len, GFP_ATOMIC | GFP_DMA);
899 
900 		if (!newskb) {
901 			CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
902 				"%s: %s: __dev_alloc_skb failed",
903 						__func__, dev->name);
904 
905 			dev_kfree_skb_any(skb);
906 			priv->stats.tx_dropped++;
907 			priv->stats.tx_errors++;
908 			priv->stats.tx_carrier_errors++;
909 			fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
910 			goto done;
911 		}
912 		newskb->protocol = skb->protocol;
913 		skb_reserve(newskb, TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
914 		skb_put_data(newskb, skb->data, skb->len);
915 		dev_kfree_skb_any(skb);
916 		skb = newskb;
917 	}
918 
919 	/*
920 	 * If channels are not running,
921 	 * notify anybody about a link failure and throw
922 	 * away packet.
923 	 */
924 	if ((fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) ||
925 	   (fsm_getstate(grp->fsm) <  MPCG_STATE_XID2INITW)) {
926 		dev_kfree_skb_any(skb);
927 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
928 			"%s(%s): inactive MPCGROUP - dropped",
929 					CTCM_FUNTAIL, dev->name);
930 		priv->stats.tx_dropped++;
931 		priv->stats.tx_errors++;
932 		priv->stats.tx_carrier_errors++;
933 		goto done;
934 	}
935 
936 	if (ctcm_test_and_set_busy(dev)) {
937 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
938 			"%s(%s): device busy - dropped",
939 					CTCM_FUNTAIL, dev->name);
940 		dev_kfree_skb_any(skb);
941 		priv->stats.tx_dropped++;
942 		priv->stats.tx_errors++;
943 		priv->stats.tx_carrier_errors++;
944 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
945 		goto done;
946 	}
947 
948 	netif_trans_update(dev);
949 	if (ctcmpc_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0) {
950 		CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
951 			"%s(%s): device error - dropped",
952 					CTCM_FUNTAIL, dev->name);
953 		dev_kfree_skb_any(skb);
954 		priv->stats.tx_dropped++;
955 		priv->stats.tx_errors++;
956 		priv->stats.tx_carrier_errors++;
957 		ctcm_clear_busy(dev);
958 		fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
959 		goto done;
960 	}
961 	ctcm_clear_busy(dev);
962 done:
963 	if (do_debug)
964 		MPC_DBF_DEV_NAME(TRACE, dev, "exit");
965 
966 	return NETDEV_TX_OK;	/* handle freeing of skb here */
967 }
968 
969 
970 /*
971  * Sets MTU of an interface.
972  *
973  *  dev		Pointer to interface struct.
974  *  new_mtu	The new MTU to use for this interface.
975  *
976  * returns 0 on success, -EINVAL if MTU is out of valid range.
977  *         (valid range is 576 .. 65527). If VM is on the
978  *         remote side, maximum MTU is 32760, however this is
979  *         not checked here.
980  */
981 static int ctcm_change_mtu(struct net_device *dev, int new_mtu)
982 {
983 	struct ctcm_priv *priv;
984 	int max_bufsize;
985 
986 	priv = dev->ml_priv;
987 	max_bufsize = priv->channel[CTCM_READ]->max_bufsize;
988 
989 	if (IS_MPC(priv)) {
990 		if (new_mtu > max_bufsize - TH_HEADER_LENGTH)
991 			return -EINVAL;
992 		dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
993 	} else {
994 		if (new_mtu > max_bufsize - LL_HEADER_LENGTH - 2)
995 			return -EINVAL;
996 		dev->hard_header_len = LL_HEADER_LENGTH + 2;
997 	}
998 	WRITE_ONCE(dev->mtu, new_mtu);
999 	return 0;
1000 }
1001 
1002 /*
1003  * Returns interface statistics of a device.
1004  *
1005  *  dev		Pointer to interface struct.
1006  *
1007  * returns Pointer to stats struct of this interface.
1008  */
1009 static struct net_device_stats *ctcm_stats(struct net_device *dev)
1010 {
1011 	return &((struct ctcm_priv *)dev->ml_priv)->stats;
1012 }
1013 
1014 static void ctcm_free_netdevice(struct net_device *dev)
1015 {
1016 	struct ctcm_priv *priv;
1017 	struct mpc_group *grp;
1018 
1019 	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1020 			"%s(%s)", CTCM_FUNTAIL, dev->name);
1021 	priv = dev->ml_priv;
1022 	if (priv) {
1023 		grp = priv->mpcg;
1024 		if (grp) {
1025 			if (grp->fsm)
1026 				kfree_fsm(grp->fsm);
1027 			dev_kfree_skb(grp->xid_skb);
1028 			dev_kfree_skb(grp->rcvd_xid_skb);
1029 			tasklet_kill(&grp->mpc_tasklet2);
1030 			kfree(grp);
1031 			priv->mpcg = NULL;
1032 		}
1033 		if (priv->fsm) {
1034 			kfree_fsm(priv->fsm);
1035 			priv->fsm = NULL;
1036 		}
1037 		kfree(priv->xid);
1038 		priv->xid = NULL;
1039 	/*
1040 	 * Note: kfree(priv); is done in "opposite" function of
1041 	 * allocator function probe_device which is remove_device.
1042 	 */
1043 	}
1044 #ifdef MODULE
1045 	free_netdev(dev);
1046 #endif
1047 }
1048 
1049 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv);
1050 
1051 static const struct net_device_ops ctcm_netdev_ops = {
1052 	.ndo_open		= ctcm_open,
1053 	.ndo_stop		= ctcm_close,
1054 	.ndo_get_stats		= ctcm_stats,
1055 	.ndo_change_mtu	   	= ctcm_change_mtu,
1056 	.ndo_start_xmit		= ctcm_tx,
1057 };
1058 
1059 static const struct net_device_ops ctcm_mpc_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		= ctcmpc_tx,
1065 };
1066 
1067 static void ctcm_dev_setup(struct net_device *dev)
1068 {
1069 	dev->type = ARPHRD_SLIP;
1070 	dev->tx_queue_len = 100;
1071 	dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1072 	dev->min_mtu = 576;
1073 	dev->max_mtu = 65527;
1074 }
1075 
1076 /*
1077  * Initialize everything of the net device except the name and the
1078  * channel structs.
1079  */
1080 static struct net_device *ctcm_init_netdevice(struct ctcm_priv *priv)
1081 {
1082 	struct net_device *dev;
1083 	struct mpc_group *grp;
1084 	if (!priv)
1085 		return NULL;
1086 
1087 	if (IS_MPC(priv))
1088 		dev = alloc_netdev(0, MPC_DEVICE_GENE, NET_NAME_UNKNOWN,
1089 				   ctcm_dev_setup);
1090 	else
1091 		dev = alloc_netdev(0, CTC_DEVICE_GENE, NET_NAME_UNKNOWN,
1092 				   ctcm_dev_setup);
1093 
1094 	if (!dev) {
1095 		CTCM_DBF_TEXT_(ERROR, CTC_DBF_CRIT,
1096 			"%s: MEMORY allocation ERROR",
1097 			CTCM_FUNTAIL);
1098 		return NULL;
1099 	}
1100 	dev->ml_priv = priv;
1101 	priv->fsm = init_fsm("ctcmdev", dev_state_names, dev_event_names,
1102 				CTCM_NR_DEV_STATES, CTCM_NR_DEV_EVENTS,
1103 				dev_fsm, dev_fsm_len, GFP_KERNEL);
1104 	if (priv->fsm == NULL) {
1105 		CTCMY_DBF_DEV(SETUP, dev, "init_fsm error");
1106 		free_netdev(dev);
1107 		return NULL;
1108 	}
1109 	fsm_newstate(priv->fsm, DEV_STATE_STOPPED);
1110 	fsm_settimer(priv->fsm, &priv->restart_timer);
1111 
1112 	if (IS_MPC(priv)) {
1113 		/*  MPC Group Initializations  */
1114 		grp = ctcmpc_init_mpc_group(priv);
1115 		if (grp == NULL) {
1116 			MPC_DBF_DEV(SETUP, dev, "init_mpc_group error");
1117 			free_netdev(dev);
1118 			return NULL;
1119 		}
1120 		tasklet_init(&grp->mpc_tasklet2,
1121 				mpc_group_ready, (unsigned long)dev);
1122 		dev->mtu = MPC_BUFSIZE_DEFAULT -
1123 				TH_HEADER_LENGTH - PDU_HEADER_LENGTH;
1124 
1125 		dev->netdev_ops = &ctcm_mpc_netdev_ops;
1126 		dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1127 		priv->buffer_size = MPC_BUFSIZE_DEFAULT;
1128 	} else {
1129 		dev->mtu = CTCM_BUFSIZE_DEFAULT - LL_HEADER_LENGTH - 2;
1130 		dev->netdev_ops = &ctcm_netdev_ops;
1131 		dev->hard_header_len = LL_HEADER_LENGTH + 2;
1132 	}
1133 
1134 	CTCMY_DBF_DEV(SETUP, dev, "finished");
1135 
1136 	return dev;
1137 }
1138 
1139 /*
1140  * Main IRQ handler.
1141  *
1142  *  cdev	The ccw_device the interrupt is for.
1143  *  intparm	interruption parameter.
1144  *  irb		interruption response block.
1145  */
1146 static void ctcm_irq_handler(struct ccw_device *cdev,
1147 				unsigned long intparm, struct irb *irb)
1148 {
1149 	struct channel		*ch;
1150 	struct net_device	*dev;
1151 	struct ctcm_priv	*priv;
1152 	struct ccwgroup_device	*cgdev;
1153 	int cstat;
1154 	int dstat;
1155 
1156 	CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
1157 		"Enter %s(%s)", CTCM_FUNTAIL, dev_name(&cdev->dev));
1158 
1159 	if (ctcm_check_irb_error(cdev, irb))
1160 		return;
1161 
1162 	cgdev = dev_get_drvdata(&cdev->dev);
1163 
1164 	cstat = irb->scsw.cmd.cstat;
1165 	dstat = irb->scsw.cmd.dstat;
1166 
1167 	/* Check for unsolicited interrupts. */
1168 	if (cgdev == NULL) {
1169 		CTCM_DBF_TEXT_(TRACE, CTC_DBF_ERROR,
1170 			"%s(%s) unsolicited irq: c-%02x d-%02x\n",
1171 			CTCM_FUNTAIL, dev_name(&cdev->dev), cstat, dstat);
1172 		dev_warn(&cdev->dev,
1173 			"The adapter received a non-specific IRQ\n");
1174 		return;
1175 	}
1176 
1177 	priv = dev_get_drvdata(&cgdev->dev);
1178 
1179 	/* Try to extract channel from driver data. */
1180 	if (priv->channel[CTCM_READ]->cdev == cdev)
1181 		ch = priv->channel[CTCM_READ];
1182 	else if (priv->channel[CTCM_WRITE]->cdev == cdev)
1183 		ch = priv->channel[CTCM_WRITE];
1184 	else {
1185 		dev_err(&cdev->dev,
1186 			"%s: Internal error: Can't determine channel for "
1187 			"interrupt device %s\n",
1188 			__func__, dev_name(&cdev->dev));
1189 			/* Explain: inconsistent internal structures */
1190 		return;
1191 	}
1192 
1193 	dev = ch->netdev;
1194 	if (dev == NULL) {
1195 		dev_err(&cdev->dev,
1196 			"%s Internal error: net_device is NULL, ch = 0x%p\n",
1197 			__func__, ch);
1198 			/* Explain: inconsistent internal structures */
1199 		return;
1200 	}
1201 
1202 	/* Copy interruption response block. */
1203 	memcpy(ch->irb, irb, sizeof(struct irb));
1204 
1205 	/* Issue error message and return on subchannel error code */
1206 	if (irb->scsw.cmd.cstat) {
1207 		fsm_event(ch->fsm, CTC_EVENT_SC_UNKNOWN, ch);
1208 		CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1209 			"%s(%s): sub-ch check %s: cs=%02x ds=%02x",
1210 				CTCM_FUNTAIL, dev->name, ch->id, cstat, dstat);
1211 		dev_warn(&cdev->dev,
1212 				"A check occurred on the subchannel\n");
1213 		return;
1214 	}
1215 
1216 	/* Check the reason-code of a unit check */
1217 	if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) {
1218 		if ((irb->ecw[0] & ch->sense_rc) == 0)
1219 			/* print it only once */
1220 			CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1221 				"%s(%s): sense=%02x, ds=%02x",
1222 				CTCM_FUNTAIL, ch->id, irb->ecw[0], dstat);
1223 		ccw_unit_check(ch, irb->ecw[0]);
1224 		return;
1225 	}
1226 	if (irb->scsw.cmd.dstat & DEV_STAT_BUSY) {
1227 		if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
1228 			fsm_event(ch->fsm, CTC_EVENT_ATTNBUSY, ch);
1229 		else
1230 			fsm_event(ch->fsm, CTC_EVENT_BUSY, ch);
1231 		return;
1232 	}
1233 	if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
1234 		fsm_event(ch->fsm, CTC_EVENT_ATTN, ch);
1235 		return;
1236 	}
1237 	if ((irb->scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS) ||
1238 	    (irb->scsw.cmd.stctl == SCSW_STCTL_STATUS_PEND) ||
1239 	    (irb->scsw.cmd.stctl ==
1240 	     (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)))
1241 		fsm_event(ch->fsm, CTC_EVENT_FINSTAT, ch);
1242 	else
1243 		fsm_event(ch->fsm, CTC_EVENT_IRQ, ch);
1244 
1245 }
1246 
1247 static const struct device_type ctcm_devtype = {
1248 	.name = "ctcm",
1249 	.groups = ctcm_attr_groups,
1250 };
1251 
1252 /*
1253  * Add ctcm specific attributes.
1254  * Add ctcm private data.
1255  *
1256  *  cgdev	pointer to ccwgroup_device just added
1257  *
1258  * returns 0 on success, !0 on failure.
1259  */
1260 static int ctcm_probe_device(struct ccwgroup_device *cgdev)
1261 {
1262 	struct ctcm_priv *priv;
1263 
1264 	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1265 			"%s %p",
1266 			__func__, cgdev);
1267 
1268 	if (!get_device(&cgdev->dev))
1269 		return -ENODEV;
1270 
1271 	priv = kzalloc(sizeof(struct ctcm_priv), GFP_KERNEL);
1272 	if (!priv) {
1273 		CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
1274 			"%s: memory allocation failure",
1275 			CTCM_FUNTAIL);
1276 		put_device(&cgdev->dev);
1277 		return -ENOMEM;
1278 	}
1279 	priv->buffer_size = CTCM_BUFSIZE_DEFAULT;
1280 	cgdev->cdev[0]->handler = ctcm_irq_handler;
1281 	cgdev->cdev[1]->handler = ctcm_irq_handler;
1282 	dev_set_drvdata(&cgdev->dev, priv);
1283 	cgdev->dev.type = &ctcm_devtype;
1284 
1285 	return 0;
1286 }
1287 
1288 /*
1289  * Add a new channel to the list of channels.
1290  * Keeps the channel list sorted.
1291  *
1292  *  cdev	The ccw_device to be added.
1293  *  type	The type class of the new channel.
1294  *  priv	Points to the private data of the ccwgroup_device.
1295  *
1296  * returns 0 on success, !0 on error.
1297  */
1298 static int add_channel(struct ccw_device *cdev, enum ctcm_channel_types type,
1299 				struct ctcm_priv *priv)
1300 {
1301 	struct channel **c = &channels;
1302 	struct channel *ch;
1303 	int ccw_num;
1304 	int rc = 0;
1305 
1306 	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1307 		"%s(%s), type %d, proto %d",
1308 			__func__, dev_name(&cdev->dev),	type, priv->protocol);
1309 
1310 	ch = kzalloc(sizeof(struct channel), GFP_KERNEL);
1311 	if (ch == NULL)
1312 		return -ENOMEM;
1313 
1314 	ch->protocol = priv->protocol;
1315 	if (IS_MPC(priv)) {
1316 		ch->discontact_th = kzalloc(TH_HEADER_LENGTH, GFP_KERNEL);
1317 		if (ch->discontact_th == NULL)
1318 					goto nomem_return;
1319 
1320 		ch->discontact_th->th_blk_flag = TH_DISCONTACT;
1321 		tasklet_init(&ch->ch_disc_tasklet,
1322 			mpc_action_send_discontact, (unsigned long)ch);
1323 
1324 		tasklet_init(&ch->ch_tasklet, ctcmpc_bh, (unsigned long)ch);
1325 		ch->max_bufsize = (MPC_BUFSIZE_DEFAULT - 35);
1326 		ccw_num = 17;
1327 	} else
1328 		ccw_num = 8;
1329 
1330 	ch->ccw = kcalloc(ccw_num, sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
1331 	if (ch->ccw == NULL)
1332 					goto nomem_return;
1333 
1334 	ch->cdev = cdev;
1335 	scnprintf(ch->id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev->dev));
1336 	ch->type = type;
1337 
1338 	/*
1339 	 * "static" ccws are used in the following way:
1340 	 *
1341 	 * ccw[0..2] (Channel program for generic I/O):
1342 	 *           0: prepare
1343 	 *           1: read or write (depending on direction) with fixed
1344 	 *              buffer (idal allocated once when buffer is allocated)
1345 	 *           2: nop
1346 	 * ccw[3..5] (Channel program for direct write of packets)
1347 	 *           3: prepare
1348 	 *           4: write (idal allocated on every write).
1349 	 *           5: nop
1350 	 * ccw[6..7] (Channel program for initial channel setup):
1351 	 *           6: set extended mode
1352 	 *           7: nop
1353 	 *
1354 	 * ch->ccw[0..5] are initialized in ch_action_start because
1355 	 * the channel's direction is yet unknown here.
1356 	 *
1357 	 * ccws used for xid2 negotiations
1358 	 *  ch-ccw[8-14] need to be used for the XID exchange either
1359 	 *    X side XID2 Processing
1360 	 *       8:  write control
1361 	 *       9:  write th
1362 	 *	     10: write XID
1363 	 *	     11: read th from secondary
1364 	 *	     12: read XID   from secondary
1365 	 *	     13: read 4 byte ID
1366 	 *	     14: nop
1367 	 *    Y side XID Processing
1368 	 *	     8:  sense
1369 	 *       9:  read th
1370 	 *	     10: read XID
1371 	 *	     11: write th
1372 	 *	     12: write XID
1373 	 *	     13: write 4 byte ID
1374 	 *	     14: nop
1375 	 *
1376 	 *  ccws used for double noop due to VM timing issues
1377 	 *  which result in unrecoverable Busy on channel
1378 	 *       15: nop
1379 	 *       16: nop
1380 	 */
1381 	ch->ccw[6].cmd_code	= CCW_CMD_SET_EXTENDED;
1382 	ch->ccw[6].flags	= CCW_FLAG_SLI;
1383 
1384 	ch->ccw[7].cmd_code	= CCW_CMD_NOOP;
1385 	ch->ccw[7].flags	= CCW_FLAG_SLI;
1386 
1387 	if (IS_MPC(priv)) {
1388 		ch->ccw[15].cmd_code = CCW_CMD_WRITE;
1389 		ch->ccw[15].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
1390 		ch->ccw[15].count    = TH_HEADER_LENGTH;
1391 		ch->ccw[15].cda      = virt_to_dma32(ch->discontact_th);
1392 
1393 		ch->ccw[16].cmd_code = CCW_CMD_NOOP;
1394 		ch->ccw[16].flags    = CCW_FLAG_SLI;
1395 
1396 		ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1397 				ctc_ch_event_names, CTC_MPC_NR_STATES,
1398 				CTC_MPC_NR_EVENTS, ctcmpc_ch_fsm,
1399 				mpc_ch_fsm_len, GFP_KERNEL);
1400 	} else {
1401 		ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1402 				ctc_ch_event_names, CTC_NR_STATES,
1403 				CTC_NR_EVENTS, ch_fsm,
1404 				ch_fsm_len, GFP_KERNEL);
1405 	}
1406 	if (ch->fsm == NULL)
1407 				goto nomem_return;
1408 
1409 	fsm_newstate(ch->fsm, CTC_STATE_IDLE);
1410 
1411 	ch->irb = kzalloc(sizeof(struct irb), GFP_KERNEL);
1412 	if (ch->irb == NULL)
1413 				goto nomem_return;
1414 
1415 	while (*c && ctcm_less_than((*c)->id, ch->id))
1416 		c = &(*c)->next;
1417 
1418 	if (*c && (!strncmp((*c)->id, ch->id, CTCM_ID_SIZE))) {
1419 		CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1420 				"%s (%s) already in list, using old entry",
1421 				__func__, (*c)->id);
1422 
1423 		goto free_return;
1424 	}
1425 
1426 	spin_lock_init(&ch->collect_lock);
1427 
1428 	fsm_settimer(ch->fsm, &ch->timer);
1429 	skb_queue_head_init(&ch->io_queue);
1430 	skb_queue_head_init(&ch->collect_queue);
1431 
1432 	if (IS_MPC(priv)) {
1433 		fsm_settimer(ch->fsm, &ch->sweep_timer);
1434 		skb_queue_head_init(&ch->sweep_queue);
1435 	}
1436 	ch->next = *c;
1437 	*c = ch;
1438 	return 0;
1439 
1440 nomem_return:
1441 	rc = -ENOMEM;
1442 
1443 free_return:	/* note that all channel pointers are 0 or valid */
1444 	kfree(ch->ccw);
1445 	kfree(ch->discontact_th);
1446 	kfree_fsm(ch->fsm);
1447 	kfree(ch->irb);
1448 	kfree(ch);
1449 	return rc;
1450 }
1451 
1452 /*
1453  * Return type of a detected device.
1454  */
1455 static enum ctcm_channel_types get_channel_type(struct ccw_device_id *id)
1456 {
1457 	enum ctcm_channel_types type;
1458 	type = (enum ctcm_channel_types)id->driver_info;
1459 
1460 	if (type == ctcm_channel_type_ficon)
1461 		type = ctcm_channel_type_escon;
1462 
1463 	return type;
1464 }
1465 
1466 /*
1467  *
1468  * Setup an interface.
1469  *
1470  *  cgdev	Device to be setup.
1471  *
1472  * returns 0 on success, !0 on failure.
1473  */
1474 static int ctcm_new_device(struct ccwgroup_device *cgdev)
1475 {
1476 	char read_id[CTCM_ID_SIZE];
1477 	char write_id[CTCM_ID_SIZE];
1478 	int direction;
1479 	enum ctcm_channel_types type;
1480 	struct ctcm_priv *priv;
1481 	struct net_device *dev;
1482 	struct ccw_device *cdev0;
1483 	struct ccw_device *cdev1;
1484 	struct channel *readc;
1485 	struct channel *writec;
1486 	int ret;
1487 	int result;
1488 
1489 	priv = dev_get_drvdata(&cgdev->dev);
1490 	if (!priv) {
1491 		result = -ENODEV;
1492 		goto out_err_result;
1493 	}
1494 
1495 	cdev0 = cgdev->cdev[0];
1496 	cdev1 = cgdev->cdev[1];
1497 
1498 	type = get_channel_type(&cdev0->id);
1499 
1500 	scnprintf(read_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev0->dev));
1501 	scnprintf(write_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev1->dev));
1502 
1503 	ret = add_channel(cdev0, type, priv);
1504 	if (ret) {
1505 		result = ret;
1506 		goto out_err_result;
1507 	}
1508 	ret = add_channel(cdev1, type, priv);
1509 	if (ret) {
1510 		result = ret;
1511 		goto out_remove_channel1;
1512 	}
1513 
1514 	ret = ccw_device_set_online(cdev0);
1515 	if (ret != 0) {
1516 		CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1517 			"%s(%s) set_online rc=%d",
1518 				CTCM_FUNTAIL, read_id, ret);
1519 		result = -EIO;
1520 		goto out_remove_channel2;
1521 	}
1522 
1523 	ret = ccw_device_set_online(cdev1);
1524 	if (ret != 0) {
1525 		CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1526 			"%s(%s) set_online rc=%d",
1527 				CTCM_FUNTAIL, write_id, ret);
1528 
1529 		result = -EIO;
1530 		goto out_ccw1;
1531 	}
1532 
1533 	dev = ctcm_init_netdevice(priv);
1534 	if (dev == NULL) {
1535 		result = -ENODEV;
1536 		goto out_ccw2;
1537 	}
1538 
1539 	for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1540 		priv->channel[direction] =
1541 			channel_get(type, direction == CTCM_READ ?
1542 				read_id : write_id, direction);
1543 		if (priv->channel[direction] == NULL) {
1544 			if (direction == CTCM_WRITE)
1545 				channel_free(priv->channel[CTCM_READ]);
1546 			result = -ENODEV;
1547 			goto out_dev;
1548 		}
1549 		priv->channel[direction]->netdev = dev;
1550 		priv->channel[direction]->protocol = priv->protocol;
1551 		priv->channel[direction]->max_bufsize = priv->buffer_size;
1552 	}
1553 	/* sysfs magic */
1554 	SET_NETDEV_DEV(dev, &cgdev->dev);
1555 
1556 	if (register_netdev(dev)) {
1557 		result = -ENODEV;
1558 		goto out_dev;
1559 	}
1560 
1561 	strscpy(priv->fsm->name, dev->name, sizeof(priv->fsm->name));
1562 
1563 	dev_info(&dev->dev,
1564 		"setup OK : r/w = %s/%s, protocol : %d\n",
1565 			priv->channel[CTCM_READ]->id,
1566 			priv->channel[CTCM_WRITE]->id, priv->protocol);
1567 
1568 	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1569 		"setup(%s) OK : r/w = %s/%s, protocol : %d", dev->name,
1570 			priv->channel[CTCM_READ]->id,
1571 			priv->channel[CTCM_WRITE]->id, priv->protocol);
1572 
1573 	return 0;
1574 out_dev:
1575 	ctcm_free_netdevice(dev);
1576 out_ccw2:
1577 	ccw_device_set_offline(cgdev->cdev[1]);
1578 out_ccw1:
1579 	ccw_device_set_offline(cgdev->cdev[0]);
1580 out_remove_channel2:
1581 	readc = channel_get(type, read_id, CTCM_READ);
1582 	channel_remove(readc);
1583 out_remove_channel1:
1584 	writec = channel_get(type, write_id, CTCM_WRITE);
1585 	channel_remove(writec);
1586 out_err_result:
1587 	return result;
1588 }
1589 
1590 /*
1591  * Shutdown an interface.
1592  *
1593  *  cgdev	Device to be shut down.
1594  *
1595  * returns 0 on success, !0 on failure.
1596  */
1597 static int ctcm_shutdown_device(struct ccwgroup_device *cgdev)
1598 {
1599 	struct ctcm_priv *priv;
1600 	struct net_device *dev;
1601 
1602 	priv = dev_get_drvdata(&cgdev->dev);
1603 	if (!priv)
1604 		return -ENODEV;
1605 
1606 	if (priv->channel[CTCM_READ]) {
1607 		dev = priv->channel[CTCM_READ]->netdev;
1608 		CTCM_DBF_DEV(SETUP, dev, "");
1609 		/* Close the device */
1610 		ctcm_close(dev);
1611 		dev->flags &= ~IFF_RUNNING;
1612 		channel_free(priv->channel[CTCM_READ]);
1613 	} else
1614 		dev = NULL;
1615 
1616 	if (priv->channel[CTCM_WRITE])
1617 		channel_free(priv->channel[CTCM_WRITE]);
1618 
1619 	if (dev) {
1620 		unregister_netdev(dev);
1621 		ctcm_free_netdevice(dev);
1622 	}
1623 
1624 	if (priv->fsm)
1625 		kfree_fsm(priv->fsm);
1626 
1627 	ccw_device_set_offline(cgdev->cdev[1]);
1628 	ccw_device_set_offline(cgdev->cdev[0]);
1629 	channel_remove(priv->channel[CTCM_READ]);
1630 	channel_remove(priv->channel[CTCM_WRITE]);
1631 	priv->channel[CTCM_READ] = priv->channel[CTCM_WRITE] = NULL;
1632 
1633 	return 0;
1634 
1635 }
1636 
1637 
1638 static void ctcm_remove_device(struct ccwgroup_device *cgdev)
1639 {
1640 	struct ctcm_priv *priv = dev_get_drvdata(&cgdev->dev);
1641 
1642 	CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1643 			"removing device %p, proto : %d",
1644 			cgdev, priv->protocol);
1645 
1646 	if (cgdev->state == CCWGROUP_ONLINE)
1647 		ctcm_shutdown_device(cgdev);
1648 	dev_set_drvdata(&cgdev->dev, NULL);
1649 	kfree(priv);
1650 	put_device(&cgdev->dev);
1651 }
1652 
1653 static struct ccw_device_id ctcm_ids[] = {
1654 	{CCW_DEVICE(0x3088, 0x08), .driver_info = ctcm_channel_type_parallel},
1655 	{CCW_DEVICE(0x3088, 0x1e), .driver_info = ctcm_channel_type_ficon},
1656 	{CCW_DEVICE(0x3088, 0x1f), .driver_info = ctcm_channel_type_escon},
1657 	{},
1658 };
1659 MODULE_DEVICE_TABLE(ccw, ctcm_ids);
1660 
1661 static struct ccw_driver ctcm_ccw_driver = {
1662 	.driver = {
1663 		.owner	= THIS_MODULE,
1664 		.name	= "ctcm",
1665 	},
1666 	.ids	= ctcm_ids,
1667 	.probe	= ccwgroup_probe_ccwdev,
1668 	.remove	= ccwgroup_remove_ccwdev,
1669 	.int_class = IRQIO_CTC,
1670 };
1671 
1672 static struct ccwgroup_driver ctcm_group_driver = {
1673 	.driver = {
1674 		.owner	= THIS_MODULE,
1675 		.name	= CTC_DRIVER_NAME,
1676 	},
1677 	.ccw_driver  = &ctcm_ccw_driver,
1678 	.setup	     = ctcm_probe_device,
1679 	.remove      = ctcm_remove_device,
1680 	.set_online  = ctcm_new_device,
1681 	.set_offline = ctcm_shutdown_device,
1682 };
1683 
1684 static ssize_t group_store(struct device_driver *ddrv, const char *buf,
1685 			   size_t count)
1686 {
1687 	int err;
1688 
1689 	err = ccwgroup_create_dev(ctcm_root_dev, &ctcm_group_driver, 2, buf);
1690 	return err ? err : count;
1691 }
1692 static DRIVER_ATTR_WO(group);
1693 
1694 static struct attribute *ctcm_drv_attrs[] = {
1695 	&driver_attr_group.attr,
1696 	NULL,
1697 };
1698 static struct attribute_group ctcm_drv_attr_group = {
1699 	.attrs = ctcm_drv_attrs,
1700 };
1701 static const struct attribute_group *ctcm_drv_attr_groups[] = {
1702 	&ctcm_drv_attr_group,
1703 	NULL,
1704 };
1705 
1706 /*
1707  * Module related routines
1708  */
1709 
1710 /*
1711  * Prepare to be unloaded. Free IRQ's and release all resources.
1712  * This is called just before this module is unloaded. It is
1713  * not called, if the usage count is !0, so we don't need to check
1714  * for that.
1715  */
1716 static void __exit ctcm_exit(void)
1717 {
1718 	ccwgroup_driver_unregister(&ctcm_group_driver);
1719 	ccw_driver_unregister(&ctcm_ccw_driver);
1720 	root_device_unregister(ctcm_root_dev);
1721 	ctcm_unregister_dbf_views();
1722 	pr_info("CTCM driver unloaded\n");
1723 }
1724 
1725 /*
1726  * Print Banner.
1727  */
1728 static void print_banner(void)
1729 {
1730 	pr_info("CTCM driver initialized\n");
1731 }
1732 
1733 /*
1734  * Initialize module.
1735  * This is called just after the module is loaded.
1736  *
1737  * returns 0 on success, !0 on error.
1738  */
1739 static int __init ctcm_init(void)
1740 {
1741 	int ret;
1742 
1743 	channels = NULL;
1744 
1745 	ret = ctcm_register_dbf_views();
1746 	if (ret)
1747 		goto out_err;
1748 	ctcm_root_dev = root_device_register("ctcm");
1749 	ret = PTR_ERR_OR_ZERO(ctcm_root_dev);
1750 	if (ret)
1751 		goto register_err;
1752 	ret = ccw_driver_register(&ctcm_ccw_driver);
1753 	if (ret)
1754 		goto ccw_err;
1755 	ctcm_group_driver.driver.groups = ctcm_drv_attr_groups;
1756 	ret = ccwgroup_driver_register(&ctcm_group_driver);
1757 	if (ret)
1758 		goto ccwgroup_err;
1759 	print_banner();
1760 	return 0;
1761 
1762 ccwgroup_err:
1763 	ccw_driver_unregister(&ctcm_ccw_driver);
1764 ccw_err:
1765 	root_device_unregister(ctcm_root_dev);
1766 register_err:
1767 	ctcm_unregister_dbf_views();
1768 out_err:
1769 	pr_err("%s / Initializing the ctcm device driver failed, ret = %d\n",
1770 		__func__, ret);
1771 	return ret;
1772 }
1773 
1774 module_init(ctcm_init);
1775 module_exit(ctcm_exit);
1776 
1777 MODULE_AUTHOR("Peter Tiedemann <ptiedem@de.ibm.com>");
1778 MODULE_DESCRIPTION("Network driver for S/390 CTC + CTCMPC (SNA)");
1779 MODULE_LICENSE("GPL");
1780 
1781