xref: /openbmc/linux/drivers/s390/net/ctcm_main.c (revision 4eb5928d)
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  */
61 static struct device *ctcm_root_dev;
62 
63 /*
64  * Linked list of all detected channels.
65  */
66 struct 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  */
75 void 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  */
188 static 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  */
200 static 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  */
252 static 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 
277 static 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  */
309 static 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 
382 int 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  */
425 int 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  */
443 int 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  */
465 static 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 	}
592 done:
593 	ctcm_clear_busy(ch->netdev);
594 	return rc;
595 }
596 
597 static 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 
652 nomem:
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  */
663 static 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;
852 nomem_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);
860 done:
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 */
877 static 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 */
920 static 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);
1010 done:
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  */
1029 static 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  */
1057 static struct net_device_stats *ctcm_stats(struct net_device *dev)
1058 {
1059 	return &((struct ctcm_priv *)dev->ml_priv)->stats;
1060 }
1061 
1062 static 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 
1097 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv);
1098 
1099 static 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 
1107 static 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 
1115 static 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  */
1128 static 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  */
1194 static 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 
1295 static 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  */
1308 static 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  */
1346 static 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 
1488 nomem_return:
1489 	rc = -ENOMEM;
1490 
1491 free_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  */
1503 static 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  */
1522 static 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;
1622 out_dev:
1623 	ctcm_free_netdevice(dev);
1624 out_ccw2:
1625 	ccw_device_set_offline(cgdev->cdev[1]);
1626 out_ccw1:
1627 	ccw_device_set_offline(cgdev->cdev[0]);
1628 out_remove_channel2:
1629 	readc = channel_get(type, read_id, CTCM_READ);
1630 	channel_remove(readc);
1631 out_remove_channel1:
1632 	writec = channel_get(type, write_id, CTCM_WRITE);
1633 	channel_remove(writec);
1634 out_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  */
1645 static 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 
1686 static 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 
1701 static 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 };
1707 MODULE_DEVICE_TABLE(ccw, ctcm_ids);
1708 
1709 static 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 
1720 static 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 
1732 static 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 }
1740 static DRIVER_ATTR_WO(group);
1741 
1742 static struct attribute *ctcm_drv_attrs[] = {
1743 	&driver_attr_group.attr,
1744 	NULL,
1745 };
1746 static struct attribute_group ctcm_drv_attr_group = {
1747 	.attrs = ctcm_drv_attrs,
1748 };
1749 static 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  */
1764 static 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  */
1776 static 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  */
1787 static 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 
1810 ccwgroup_err:
1811 	ccw_driver_unregister(&ctcm_ccw_driver);
1812 ccw_err:
1813 	root_device_unregister(ctcm_root_dev);
1814 register_err:
1815 	ctcm_unregister_dbf_views();
1816 out_err:
1817 	pr_err("%s / Initializing the ctcm device driver failed, ret = %d\n",
1818 		__func__, ret);
1819 	return ret;
1820 }
1821 
1822 module_init(ctcm_init);
1823 module_exit(ctcm_exit);
1824 
1825 MODULE_AUTHOR("Peter Tiedemann <ptiedem@de.ibm.com>");
1826 MODULE_DESCRIPTION("Network driver for S/390 CTC + CTCMPC (SNA)");
1827 MODULE_LICENSE("GPL");
1828 
1829