Merge remote-tracking branches 'asoc/fix/msm8916', 'asoc/fix/nau8825', 'asoc/fix...
[sfrench/cifs-2.6.git] / drivers / s390 / net / ctcm_main.c
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],
573                                         (unsigned long)ch, 0xff, 0);
574         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
575         if (ccw_idx == 3)
576                 ch->prof.doios_single++;
577         if (rc != 0) {
578                 fsm_deltimer(&ch->timer);
579                 ctcm_ccw_check_rc(ch, rc, "single skb TX");
580                 if (ccw_idx == 3)
581                         skb_dequeue_tail(&ch->io_queue);
582                 /*
583                  * Remove our header. It gets added
584                  * again on retransmit.
585                  */
586                 skb_pull(skb, LL_HEADER_LENGTH + 2);
587         } else if (ccw_idx == 0) {
588                 struct net_device *dev = ch->netdev;
589                 struct ctcm_priv *priv = dev->ml_priv;
590                 priv->stats.tx_packets++;
591                 priv->stats.tx_bytes += skb->len - LL_HEADER_LENGTH;
592         }
593 done:
594         ctcm_clear_busy(ch->netdev);
595         return rc;
596 }
597
598 static void ctcmpc_send_sweep_req(struct channel *rch)
599 {
600         struct net_device *dev = rch->netdev;
601         struct ctcm_priv *priv;
602         struct mpc_group *grp;
603         struct th_sweep *header;
604         struct sk_buff *sweep_skb;
605         struct channel *ch;
606         /* int rc = 0; */
607
608         priv = dev->ml_priv;
609         grp = priv->mpcg;
610         ch = priv->channel[CTCM_WRITE];
611
612         /* sweep processing is not complete until response and request */
613         /* has completed for all read channels in group                */
614         if (grp->in_sweep == 0) {
615                 grp->in_sweep = 1;
616                 grp->sweep_rsp_pend_num = grp->active_channels[CTCM_READ];
617                 grp->sweep_req_pend_num = grp->active_channels[CTCM_READ];
618         }
619
620         sweep_skb = __dev_alloc_skb(MPC_BUFSIZE_DEFAULT, GFP_ATOMIC|GFP_DMA);
621
622         if (sweep_skb == NULL)  {
623                 /* rc = -ENOMEM; */
624                                 goto nomem;
625         }
626
627         header = kmalloc(TH_SWEEP_LENGTH, gfp_type());
628
629         if (!header) {
630                 dev_kfree_skb_any(sweep_skb);
631                 /* rc = -ENOMEM; */
632                                 goto nomem;
633         }
634
635         header->th.th_seg       = 0x00 ;
636         header->th.th_ch_flag   = TH_SWEEP_REQ;  /* 0x0f */
637         header->th.th_blk_flag  = 0x00;
638         header->th.th_is_xid    = 0x00;
639         header->th.th_seq_num   = 0x00;
640         header->sw.th_last_seq  = ch->th_seq_num;
641
642         skb_put_data(sweep_skb, header, TH_SWEEP_LENGTH);
643
644         kfree(header);
645
646         netif_trans_update(dev);
647         skb_queue_tail(&ch->sweep_queue, sweep_skb);
648
649         fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
650
651         return;
652
653 nomem:
654         grp->in_sweep = 0;
655         ctcm_clear_busy(dev);
656         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
657
658         return;
659 }
660
661 /*
662  * MPC mode version of transmit_skb
663  */
664 static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
665 {
666         struct pdu *p_header;
667         struct net_device *dev = ch->netdev;
668         struct ctcm_priv *priv = dev->ml_priv;
669         struct mpc_group *grp = priv->mpcg;
670         struct th_header *header;
671         struct sk_buff *nskb;
672         int rc = 0;
673         int ccw_idx;
674         unsigned long hi;
675         unsigned long saveflags = 0;    /* avoids compiler warning */
676
677         CTCM_PR_DEBUG("Enter %s: %s, cp=%i ch=0x%p id=%s state=%s\n",
678                         __func__, dev->name, smp_processor_id(), ch,
679                                         ch->id, fsm_getstate_str(ch->fsm));
680
681         if ((fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) || grp->in_sweep) {
682                 spin_lock_irqsave(&ch->collect_lock, saveflags);
683                 refcount_inc(&skb->users);
684                 p_header = kmalloc(PDU_HEADER_LENGTH, gfp_type());
685
686                 if (!p_header) {
687                         spin_unlock_irqrestore(&ch->collect_lock, saveflags);
688                                 goto nomem_exit;
689                 }
690
691                 p_header->pdu_offset = skb->len;
692                 p_header->pdu_proto = 0x01;
693                 p_header->pdu_flag = 0x00;
694                 if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
695                         p_header->pdu_flag |= PDU_FIRST | PDU_CNTL;
696                 } else {
697                         p_header->pdu_flag |= PDU_FIRST;
698                 }
699                 p_header->pdu_seq = 0;
700                 memcpy(skb_push(skb, PDU_HEADER_LENGTH), p_header,
701                        PDU_HEADER_LENGTH);
702
703                 CTCM_PR_DEBUG("%s(%s): Put on collect_q - skb len: %04x \n"
704                                 "pdu header and data for up to 32 bytes:\n",
705                                 __func__, dev->name, skb->len);
706                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
707
708                 skb_queue_tail(&ch->collect_queue, skb);
709                 ch->collect_len += skb->len;
710                 kfree(p_header);
711
712                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
713                         goto done;
714         }
715
716         /*
717          * Protect skb against beeing free'd by upper
718          * layers.
719          */
720         refcount_inc(&skb->users);
721
722         /*
723          * IDAL support in CTCM is broken, so we have to
724          * care about skb's above 2G ourselves.
725          */
726         hi = ((unsigned long)skb->tail + TH_HEADER_LENGTH) >> 31;
727         if (hi) {
728                 nskb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
729                 if (!nskb) {
730                         goto nomem_exit;
731                 } else {
732                         skb_put_data(nskb, skb->data, skb->len);
733                         refcount_inc(&nskb->users);
734                         refcount_dec(&skb->users);
735                         dev_kfree_skb_irq(skb);
736                         skb = nskb;
737                 }
738         }
739
740         p_header = kmalloc(PDU_HEADER_LENGTH, gfp_type());
741
742         if (!p_header)
743                 goto nomem_exit;
744
745         p_header->pdu_offset = skb->len;
746         p_header->pdu_proto = 0x01;
747         p_header->pdu_flag = 0x00;
748         p_header->pdu_seq = 0;
749         if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
750                 p_header->pdu_flag |= PDU_FIRST | PDU_CNTL;
751         } else {
752                 p_header->pdu_flag |= PDU_FIRST;
753         }
754         memcpy(skb_push(skb, PDU_HEADER_LENGTH), p_header, PDU_HEADER_LENGTH);
755
756         kfree(p_header);
757
758         if (ch->collect_len > 0) {
759                 spin_lock_irqsave(&ch->collect_lock, saveflags);
760                 skb_queue_tail(&ch->collect_queue, skb);
761                 ch->collect_len += skb->len;
762                 skb = skb_dequeue(&ch->collect_queue);
763                 ch->collect_len -= skb->len;
764                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
765         }
766
767         p_header = (struct pdu *)skb->data;
768         p_header->pdu_flag |= PDU_LAST;
769
770         ch->prof.txlen += skb->len - PDU_HEADER_LENGTH;
771
772         header = kmalloc(TH_HEADER_LENGTH, gfp_type());
773         if (!header)
774                 goto nomem_exit;
775
776         header->th_seg = 0x00;
777         header->th_ch_flag = TH_HAS_PDU;  /* Normal data */
778         header->th_blk_flag = 0x00;
779         header->th_is_xid = 0x00;          /* Just data here */
780         ch->th_seq_num++;
781         header->th_seq_num = ch->th_seq_num;
782
783         CTCM_PR_DBGDATA("%s(%s) ToVTAM_th_seq= %08x\n" ,
784                        __func__, dev->name, ch->th_seq_num);
785
786         /* put the TH on the packet */
787         memcpy(skb_push(skb, TH_HEADER_LENGTH), header, TH_HEADER_LENGTH);
788
789         kfree(header);
790
791         CTCM_PR_DBGDATA("%s(%s): skb len: %04x\n - pdu header and data for "
792                         "up to 32 bytes sent to vtam:\n",
793                                 __func__, dev->name, skb->len);
794         CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
795
796         ch->ccw[4].count = skb->len;
797         if (set_normalized_cda(&ch->ccw[4], skb->data)) {
798                 /*
799                  * idal allocation failed, try via copying to trans_skb.
800                  * trans_skb usually has a pre-allocated idal.
801                  */
802                 if (ctcm_checkalloc_buffer(ch)) {
803                         /*
804                          * Remove our header.
805                          * It gets added again on retransmit.
806                          */
807                                 goto nomem_exit;
808                 }
809
810                 skb_reset_tail_pointer(ch->trans_skb);
811                 ch->trans_skb->len = 0;
812                 ch->ccw[1].count = skb->len;
813                 skb_put_data(ch->trans_skb, skb->data, skb->len);
814                 refcount_dec(&skb->users);
815                 dev_kfree_skb_irq(skb);
816                 ccw_idx = 0;
817                 CTCM_PR_DBGDATA("%s(%s): trans_skb len: %04x\n"
818                                 "up to 32 bytes sent to vtam:\n",
819                                 __func__, dev->name, ch->trans_skb->len);
820                 CTCM_D3_DUMP((char *)ch->trans_skb->data,
821                                 min_t(int, 32, ch->trans_skb->len));
822         } else {
823                 skb_queue_tail(&ch->io_queue, skb);
824                 ccw_idx = 3;
825         }
826         ch->retry = 0;
827         fsm_newstate(ch->fsm, CTC_STATE_TX);
828         fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
829
830         if (do_debug_ccw)
831                 ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
832                                         sizeof(struct ccw1) * 3);
833
834         spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
835         ch->prof.send_stamp = jiffies;
836         rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx],
837                                         (unsigned long)ch, 0xff, 0);
838         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
839         if (ccw_idx == 3)
840                 ch->prof.doios_single++;
841         if (rc != 0) {
842                 fsm_deltimer(&ch->timer);
843                 ctcm_ccw_check_rc(ch, rc, "single skb TX");
844                 if (ccw_idx == 3)
845                         skb_dequeue_tail(&ch->io_queue);
846         } else if (ccw_idx == 0) {
847                 priv->stats.tx_packets++;
848                 priv->stats.tx_bytes += skb->len - TH_HEADER_LENGTH;
849         }
850         if (ch->th_seq_num > 0xf0000000)        /* Chose at random. */
851                 ctcmpc_send_sweep_req(ch);
852
853         goto done;
854 nomem_exit:
855         CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_CRIT,
856                         "%s(%s): MEMORY allocation ERROR\n",
857                         CTCM_FUNTAIL, ch->id);
858         rc = -ENOMEM;
859         refcount_dec(&skb->users);
860         dev_kfree_skb_any(skb);
861         fsm_event(priv->mpcg->fsm, MPCG_EVENT_INOP, dev);
862 done:
863         CTCM_PR_DEBUG("Exit %s(%s)\n", __func__, dev->name);
864         return rc;
865 }
866
867 /**
868  * Start transmission of a packet.
869  * Called from generic network device layer.
870  *
871  *  skb         Pointer to buffer containing the packet.
872  *  dev         Pointer to interface struct.
873  *
874  * returns 0 if packet consumed, !0 if packet rejected.
875  *         Note: If we return !0, then the packet is free'd by
876  *               the generic network layer.
877  */
878 /* first merge version - leaving both functions separated */
879 static int ctcm_tx(struct sk_buff *skb, struct net_device *dev)
880 {
881         struct ctcm_priv *priv = dev->ml_priv;
882
883         if (skb == NULL) {
884                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
885                                 "%s(%s): NULL sk_buff passed",
886                                         CTCM_FUNTAIL, dev->name);
887                 priv->stats.tx_dropped++;
888                 return NETDEV_TX_OK;
889         }
890         if (skb_headroom(skb) < (LL_HEADER_LENGTH + 2)) {
891                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
892                         "%s(%s): Got sk_buff with head room < %ld bytes",
893                         CTCM_FUNTAIL, dev->name, LL_HEADER_LENGTH + 2);
894                 dev_kfree_skb(skb);
895                 priv->stats.tx_dropped++;
896                 return NETDEV_TX_OK;
897         }
898
899         /*
900          * If channels are not running, try to restart them
901          * and throw away packet.
902          */
903         if (fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) {
904                 fsm_event(priv->fsm, DEV_EVENT_START, dev);
905                 dev_kfree_skb(skb);
906                 priv->stats.tx_dropped++;
907                 priv->stats.tx_errors++;
908                 priv->stats.tx_carrier_errors++;
909                 return NETDEV_TX_OK;
910         }
911
912         if (ctcm_test_and_set_busy(dev))
913                 return NETDEV_TX_BUSY;
914
915         netif_trans_update(dev);
916         if (ctcm_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0)
917                 return NETDEV_TX_BUSY;
918         return NETDEV_TX_OK;
919 }
920
921 /* unmerged MPC variant of ctcm_tx */
922 static int ctcmpc_tx(struct sk_buff *skb, struct net_device *dev)
923 {
924         int len = 0;
925         struct ctcm_priv *priv = dev->ml_priv;
926         struct mpc_group *grp  = priv->mpcg;
927         struct sk_buff *newskb = NULL;
928
929         /*
930          * Some sanity checks ...
931          */
932         if (skb == NULL) {
933                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
934                         "%s(%s): NULL sk_buff passed",
935                                         CTCM_FUNTAIL, dev->name);
936                 priv->stats.tx_dropped++;
937                                         goto done;
938         }
939         if (skb_headroom(skb) < (TH_HEADER_LENGTH + PDU_HEADER_LENGTH)) {
940                 CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
941                         "%s(%s): Got sk_buff with head room < %ld bytes",
942                         CTCM_FUNTAIL, dev->name,
943                                 TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
944
945                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
946
947                 len =  skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
948                 newskb = __dev_alloc_skb(len, gfp_type() | GFP_DMA);
949
950                 if (!newskb) {
951                         CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
952                                 "%s: %s: __dev_alloc_skb failed",
953                                                 __func__, dev->name);
954
955                         dev_kfree_skb_any(skb);
956                         priv->stats.tx_dropped++;
957                         priv->stats.tx_errors++;
958                         priv->stats.tx_carrier_errors++;
959                         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
960                                         goto done;
961                 }
962                 newskb->protocol = skb->protocol;
963                 skb_reserve(newskb, TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
964                 skb_put_data(newskb, skb->data, skb->len);
965                 dev_kfree_skb_any(skb);
966                 skb = newskb;
967         }
968
969         /*
970          * If channels are not running,
971          * notify anybody about a link failure and throw
972          * away packet.
973          */
974         if ((fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) ||
975            (fsm_getstate(grp->fsm) <  MPCG_STATE_XID2INITW)) {
976                 dev_kfree_skb_any(skb);
977                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
978                         "%s(%s): inactive MPCGROUP - dropped",
979                                         CTCM_FUNTAIL, dev->name);
980                 priv->stats.tx_dropped++;
981                 priv->stats.tx_errors++;
982                 priv->stats.tx_carrier_errors++;
983                                         goto done;
984         }
985
986         if (ctcm_test_and_set_busy(dev)) {
987                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
988                         "%s(%s): device busy - dropped",
989                                         CTCM_FUNTAIL, dev->name);
990                 dev_kfree_skb_any(skb);
991                 priv->stats.tx_dropped++;
992                 priv->stats.tx_errors++;
993                 priv->stats.tx_carrier_errors++;
994                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
995                                         goto done;
996         }
997
998         netif_trans_update(dev);
999         if (ctcmpc_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0) {
1000                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
1001                         "%s(%s): device error - dropped",
1002                                         CTCM_FUNTAIL, dev->name);
1003                 dev_kfree_skb_any(skb);
1004                 priv->stats.tx_dropped++;
1005                 priv->stats.tx_errors++;
1006                 priv->stats.tx_carrier_errors++;
1007                 ctcm_clear_busy(dev);
1008                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
1009                                         goto done;
1010         }
1011         ctcm_clear_busy(dev);
1012 done:
1013         if (do_debug)
1014                 MPC_DBF_DEV_NAME(TRACE, dev, "exit");
1015
1016         return NETDEV_TX_OK;    /* handle freeing of skb here */
1017 }
1018
1019
1020 /**
1021  * Sets MTU of an interface.
1022  *
1023  *  dev         Pointer to interface struct.
1024  *  new_mtu     The new MTU to use for this interface.
1025  *
1026  * returns 0 on success, -EINVAL if MTU is out of valid range.
1027  *         (valid range is 576 .. 65527). If VM is on the
1028  *         remote side, maximum MTU is 32760, however this is
1029  *         not checked here.
1030  */
1031 static int ctcm_change_mtu(struct net_device *dev, int new_mtu)
1032 {
1033         struct ctcm_priv *priv;
1034         int max_bufsize;
1035
1036         priv = dev->ml_priv;
1037         max_bufsize = priv->channel[CTCM_READ]->max_bufsize;
1038
1039         if (IS_MPC(priv)) {
1040                 if (new_mtu > max_bufsize - TH_HEADER_LENGTH)
1041                         return -EINVAL;
1042                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1043         } else {
1044                 if (new_mtu > max_bufsize - LL_HEADER_LENGTH - 2)
1045                         return -EINVAL;
1046                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
1047         }
1048         dev->mtu = new_mtu;
1049         return 0;
1050 }
1051
1052 /**
1053  * Returns interface statistics of a device.
1054  *
1055  *  dev         Pointer to interface struct.
1056  *
1057  * returns Pointer to stats struct of this interface.
1058  */
1059 static struct net_device_stats *ctcm_stats(struct net_device *dev)
1060 {
1061         return &((struct ctcm_priv *)dev->ml_priv)->stats;
1062 }
1063
1064 static void ctcm_free_netdevice(struct net_device *dev)
1065 {
1066         struct ctcm_priv *priv;
1067         struct mpc_group *grp;
1068
1069         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1070                         "%s(%s)", CTCM_FUNTAIL, dev->name);
1071         priv = dev->ml_priv;
1072         if (priv) {
1073                 grp = priv->mpcg;
1074                 if (grp) {
1075                         if (grp->fsm)
1076                                 kfree_fsm(grp->fsm);
1077                         if (grp->xid_skb)
1078                                 dev_kfree_skb(grp->xid_skb);
1079                         if (grp->rcvd_xid_skb)
1080                                 dev_kfree_skb(grp->rcvd_xid_skb);
1081                         tasklet_kill(&grp->mpc_tasklet2);
1082                         kfree(grp);
1083                         priv->mpcg = NULL;
1084                 }
1085                 if (priv->fsm) {
1086                         kfree_fsm(priv->fsm);
1087                         priv->fsm = NULL;
1088                 }
1089                 kfree(priv->xid);
1090                 priv->xid = NULL;
1091         /*
1092          * Note: kfree(priv); is done in "opposite" function of
1093          * allocator function probe_device which is remove_device.
1094          */
1095         }
1096 #ifdef MODULE
1097         free_netdev(dev);
1098 #endif
1099 }
1100
1101 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv);
1102
1103 static const struct net_device_ops ctcm_netdev_ops = {
1104         .ndo_open               = ctcm_open,
1105         .ndo_stop               = ctcm_close,
1106         .ndo_get_stats          = ctcm_stats,
1107         .ndo_change_mtu         = ctcm_change_mtu,
1108         .ndo_start_xmit         = ctcm_tx,
1109 };
1110
1111 static const struct net_device_ops ctcm_mpc_netdev_ops = {
1112         .ndo_open               = ctcm_open,
1113         .ndo_stop               = ctcm_close,
1114         .ndo_get_stats          = ctcm_stats,
1115         .ndo_change_mtu         = ctcm_change_mtu,
1116         .ndo_start_xmit         = ctcmpc_tx,
1117 };
1118
1119 static void ctcm_dev_setup(struct net_device *dev)
1120 {
1121         dev->type = ARPHRD_SLIP;
1122         dev->tx_queue_len = 100;
1123         dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1124         dev->min_mtu = 576;
1125         dev->max_mtu = 65527;
1126 }
1127
1128 /*
1129  * Initialize everything of the net device except the name and the
1130  * channel structs.
1131  */
1132 static struct net_device *ctcm_init_netdevice(struct ctcm_priv *priv)
1133 {
1134         struct net_device *dev;
1135         struct mpc_group *grp;
1136         if (!priv)
1137                 return NULL;
1138
1139         if (IS_MPC(priv))
1140                 dev = alloc_netdev(0, MPC_DEVICE_GENE, NET_NAME_UNKNOWN,
1141                                    ctcm_dev_setup);
1142         else
1143                 dev = alloc_netdev(0, CTC_DEVICE_GENE, NET_NAME_UNKNOWN,
1144                                    ctcm_dev_setup);
1145
1146         if (!dev) {
1147                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_CRIT,
1148                         "%s: MEMORY allocation ERROR",
1149                         CTCM_FUNTAIL);
1150                 return NULL;
1151         }
1152         dev->ml_priv = priv;
1153         priv->fsm = init_fsm("ctcmdev", dev_state_names, dev_event_names,
1154                                 CTCM_NR_DEV_STATES, CTCM_NR_DEV_EVENTS,
1155                                 dev_fsm, dev_fsm_len, GFP_KERNEL);
1156         if (priv->fsm == NULL) {
1157                 CTCMY_DBF_DEV(SETUP, dev, "init_fsm error");
1158                 free_netdev(dev);
1159                 return NULL;
1160         }
1161         fsm_newstate(priv->fsm, DEV_STATE_STOPPED);
1162         fsm_settimer(priv->fsm, &priv->restart_timer);
1163
1164         if (IS_MPC(priv)) {
1165                 /*  MPC Group Initializations  */
1166                 grp = ctcmpc_init_mpc_group(priv);
1167                 if (grp == NULL) {
1168                         MPC_DBF_DEV(SETUP, dev, "init_mpc_group error");
1169                         free_netdev(dev);
1170                         return NULL;
1171                 }
1172                 tasklet_init(&grp->mpc_tasklet2,
1173                                 mpc_group_ready, (unsigned long)dev);
1174                 dev->mtu = MPC_BUFSIZE_DEFAULT -
1175                                 TH_HEADER_LENGTH - PDU_HEADER_LENGTH;
1176
1177                 dev->netdev_ops = &ctcm_mpc_netdev_ops;
1178                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1179                 priv->buffer_size = MPC_BUFSIZE_DEFAULT;
1180         } else {
1181                 dev->mtu = CTCM_BUFSIZE_DEFAULT - LL_HEADER_LENGTH - 2;
1182                 dev->netdev_ops = &ctcm_netdev_ops;
1183                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
1184         }
1185
1186         CTCMY_DBF_DEV(SETUP, dev, "finished");
1187
1188         return dev;
1189 }
1190
1191 /**
1192  * Main IRQ handler.
1193  *
1194  *  cdev        The ccw_device the interrupt is for.
1195  *  intparm     interruption parameter.
1196  *  irb         interruption response block.
1197  */
1198 static void ctcm_irq_handler(struct ccw_device *cdev,
1199                                 unsigned long intparm, struct irb *irb)
1200 {
1201         struct channel          *ch;
1202         struct net_device       *dev;
1203         struct ctcm_priv        *priv;
1204         struct ccwgroup_device  *cgdev;
1205         int cstat;
1206         int dstat;
1207
1208         CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
1209                 "Enter %s(%s)", CTCM_FUNTAIL, dev_name(&cdev->dev));
1210
1211         if (ctcm_check_irb_error(cdev, irb))
1212                 return;
1213
1214         cgdev = dev_get_drvdata(&cdev->dev);
1215
1216         cstat = irb->scsw.cmd.cstat;
1217         dstat = irb->scsw.cmd.dstat;
1218
1219         /* Check for unsolicited interrupts. */
1220         if (cgdev == NULL) {
1221                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_ERROR,
1222                         "%s(%s) unsolicited irq: c-%02x d-%02x\n",
1223                         CTCM_FUNTAIL, dev_name(&cdev->dev), cstat, dstat);
1224                 dev_warn(&cdev->dev,
1225                         "The adapter received a non-specific IRQ\n");
1226                 return;
1227         }
1228
1229         priv = dev_get_drvdata(&cgdev->dev);
1230
1231         /* Try to extract channel from driver data. */
1232         if (priv->channel[CTCM_READ]->cdev == cdev)
1233                 ch = priv->channel[CTCM_READ];
1234         else if (priv->channel[CTCM_WRITE]->cdev == cdev)
1235                 ch = priv->channel[CTCM_WRITE];
1236         else {
1237                 dev_err(&cdev->dev,
1238                         "%s: Internal error: Can't determine channel for "
1239                         "interrupt device %s\n",
1240                         __func__, dev_name(&cdev->dev));
1241                         /* Explain: inconsistent internal structures */
1242                 return;
1243         }
1244
1245         dev = ch->netdev;
1246         if (dev == NULL) {
1247                 dev_err(&cdev->dev,
1248                         "%s Internal error: net_device is NULL, ch = 0x%p\n",
1249                         __func__, ch);
1250                         /* Explain: inconsistent internal structures */
1251                 return;
1252         }
1253
1254         /* Copy interruption response block. */
1255         memcpy(ch->irb, irb, sizeof(struct irb));
1256
1257         /* Issue error message and return on subchannel error code */
1258         if (irb->scsw.cmd.cstat) {
1259                 fsm_event(ch->fsm, CTC_EVENT_SC_UNKNOWN, ch);
1260                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1261                         "%s(%s): sub-ch check %s: cs=%02x ds=%02x",
1262                                 CTCM_FUNTAIL, dev->name, ch->id, cstat, dstat);
1263                 dev_warn(&cdev->dev,
1264                                 "A check occurred on the subchannel\n");
1265                 return;
1266         }
1267
1268         /* Check the reason-code of a unit check */
1269         if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) {
1270                 if ((irb->ecw[0] & ch->sense_rc) == 0)
1271                         /* print it only once */
1272                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1273                                 "%s(%s): sense=%02x, ds=%02x",
1274                                 CTCM_FUNTAIL, ch->id, irb->ecw[0], dstat);
1275                 ccw_unit_check(ch, irb->ecw[0]);
1276                 return;
1277         }
1278         if (irb->scsw.cmd.dstat & DEV_STAT_BUSY) {
1279                 if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
1280                         fsm_event(ch->fsm, CTC_EVENT_ATTNBUSY, ch);
1281                 else
1282                         fsm_event(ch->fsm, CTC_EVENT_BUSY, ch);
1283                 return;
1284         }
1285         if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
1286                 fsm_event(ch->fsm, CTC_EVENT_ATTN, ch);
1287                 return;
1288         }
1289         if ((irb->scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS) ||
1290             (irb->scsw.cmd.stctl == SCSW_STCTL_STATUS_PEND) ||
1291             (irb->scsw.cmd.stctl ==
1292              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)))
1293                 fsm_event(ch->fsm, CTC_EVENT_FINSTAT, ch);
1294         else
1295                 fsm_event(ch->fsm, CTC_EVENT_IRQ, ch);
1296
1297 }
1298
1299 static const struct device_type ctcm_devtype = {
1300         .name = "ctcm",
1301         .groups = ctcm_attr_groups,
1302 };
1303
1304 /**
1305  * Add ctcm specific attributes.
1306  * Add ctcm private data.
1307  *
1308  *  cgdev       pointer to ccwgroup_device just added
1309  *
1310  * returns 0 on success, !0 on failure.
1311  */
1312 static int ctcm_probe_device(struct ccwgroup_device *cgdev)
1313 {
1314         struct ctcm_priv *priv;
1315
1316         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1317                         "%s %p",
1318                         __func__, cgdev);
1319
1320         if (!get_device(&cgdev->dev))
1321                 return -ENODEV;
1322
1323         priv = kzalloc(sizeof(struct ctcm_priv), GFP_KERNEL);
1324         if (!priv) {
1325                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
1326                         "%s: memory allocation failure",
1327                         CTCM_FUNTAIL);
1328                 put_device(&cgdev->dev);
1329                 return -ENOMEM;
1330         }
1331         priv->buffer_size = CTCM_BUFSIZE_DEFAULT;
1332         cgdev->cdev[0]->handler = ctcm_irq_handler;
1333         cgdev->cdev[1]->handler = ctcm_irq_handler;
1334         dev_set_drvdata(&cgdev->dev, priv);
1335         cgdev->dev.type = &ctcm_devtype;
1336
1337         return 0;
1338 }
1339
1340 /**
1341  * Add a new channel to the list of channels.
1342  * Keeps the channel list sorted.
1343  *
1344  *  cdev        The ccw_device to be added.
1345  *  type        The type class of the new channel.
1346  *  priv        Points to the private data of the ccwgroup_device.
1347  *
1348  * returns 0 on success, !0 on error.
1349  */
1350 static int add_channel(struct ccw_device *cdev, enum ctcm_channel_types type,
1351                                 struct ctcm_priv *priv)
1352 {
1353         struct channel **c = &channels;
1354         struct channel *ch;
1355         int ccw_num;
1356         int rc = 0;
1357
1358         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1359                 "%s(%s), type %d, proto %d",
1360                         __func__, dev_name(&cdev->dev), type, priv->protocol);
1361
1362         ch = kzalloc(sizeof(struct channel), GFP_KERNEL);
1363         if (ch == NULL)
1364                 return -ENOMEM;
1365
1366         ch->protocol = priv->protocol;
1367         if (IS_MPC(priv)) {
1368                 ch->discontact_th = kzalloc(TH_HEADER_LENGTH, gfp_type());
1369                 if (ch->discontact_th == NULL)
1370                                         goto nomem_return;
1371
1372                 ch->discontact_th->th_blk_flag = TH_DISCONTACT;
1373                 tasklet_init(&ch->ch_disc_tasklet,
1374                         mpc_action_send_discontact, (unsigned long)ch);
1375
1376                 tasklet_init(&ch->ch_tasklet, ctcmpc_bh, (unsigned long)ch);
1377                 ch->max_bufsize = (MPC_BUFSIZE_DEFAULT - 35);
1378                 ccw_num = 17;
1379         } else
1380                 ccw_num = 8;
1381
1382         ch->ccw = kzalloc(ccw_num * sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
1383         if (ch->ccw == NULL)
1384                                         goto nomem_return;
1385
1386         ch->cdev = cdev;
1387         snprintf(ch->id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev->dev));
1388         ch->type = type;
1389
1390         /**
1391          * "static" ccws are used in the following way:
1392          *
1393          * ccw[0..2] (Channel program for generic I/O):
1394          *           0: prepare
1395          *           1: read or write (depending on direction) with fixed
1396          *              buffer (idal allocated once when buffer is allocated)
1397          *           2: nop
1398          * ccw[3..5] (Channel program for direct write of packets)
1399          *           3: prepare
1400          *           4: write (idal allocated on every write).
1401          *           5: nop
1402          * ccw[6..7] (Channel program for initial channel setup):
1403          *           6: set extended mode
1404          *           7: nop
1405          *
1406          * ch->ccw[0..5] are initialized in ch_action_start because
1407          * the channel's direction is yet unknown here.
1408          *
1409          * ccws used for xid2 negotiations
1410          *  ch-ccw[8-14] need to be used for the XID exchange either
1411          *    X side XID2 Processing
1412          *       8:  write control
1413          *       9:  write th
1414          *           10: write XID
1415          *           11: read th from secondary
1416          *           12: read XID   from secondary
1417          *           13: read 4 byte ID
1418          *           14: nop
1419          *    Y side XID Processing
1420          *           8:  sense
1421          *       9:  read th
1422          *           10: read XID
1423          *           11: write th
1424          *           12: write XID
1425          *           13: write 4 byte ID
1426          *           14: nop
1427          *
1428          *  ccws used for double noop due to VM timing issues
1429          *  which result in unrecoverable Busy on channel
1430          *       15: nop
1431          *       16: nop
1432          */
1433         ch->ccw[6].cmd_code     = CCW_CMD_SET_EXTENDED;
1434         ch->ccw[6].flags        = CCW_FLAG_SLI;
1435
1436         ch->ccw[7].cmd_code     = CCW_CMD_NOOP;
1437         ch->ccw[7].flags        = CCW_FLAG_SLI;
1438
1439         if (IS_MPC(priv)) {
1440                 ch->ccw[15].cmd_code = CCW_CMD_WRITE;
1441                 ch->ccw[15].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
1442                 ch->ccw[15].count    = TH_HEADER_LENGTH;
1443                 ch->ccw[15].cda      = virt_to_phys(ch->discontact_th);
1444
1445                 ch->ccw[16].cmd_code = CCW_CMD_NOOP;
1446                 ch->ccw[16].flags    = CCW_FLAG_SLI;
1447
1448                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1449                                 ctc_ch_event_names, CTC_MPC_NR_STATES,
1450                                 CTC_MPC_NR_EVENTS, ctcmpc_ch_fsm,
1451                                 mpc_ch_fsm_len, GFP_KERNEL);
1452         } else {
1453                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1454                                 ctc_ch_event_names, CTC_NR_STATES,
1455                                 CTC_NR_EVENTS, ch_fsm,
1456                                 ch_fsm_len, GFP_KERNEL);
1457         }
1458         if (ch->fsm == NULL)
1459                                 goto nomem_return;
1460
1461         fsm_newstate(ch->fsm, CTC_STATE_IDLE);
1462
1463         ch->irb = kzalloc(sizeof(struct irb), GFP_KERNEL);
1464         if (ch->irb == NULL)
1465                                 goto nomem_return;
1466
1467         while (*c && ctcm_less_than((*c)->id, ch->id))
1468                 c = &(*c)->next;
1469
1470         if (*c && (!strncmp((*c)->id, ch->id, CTCM_ID_SIZE))) {
1471                 CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1472                                 "%s (%s) already in list, using old entry",
1473                                 __func__, (*c)->id);
1474
1475                                 goto free_return;
1476         }
1477
1478         spin_lock_init(&ch->collect_lock);
1479
1480         fsm_settimer(ch->fsm, &ch->timer);
1481         skb_queue_head_init(&ch->io_queue);
1482         skb_queue_head_init(&ch->collect_queue);
1483
1484         if (IS_MPC(priv)) {
1485                 fsm_settimer(ch->fsm, &ch->sweep_timer);
1486                 skb_queue_head_init(&ch->sweep_queue);
1487         }
1488         ch->next = *c;
1489         *c = ch;
1490         return 0;
1491
1492 nomem_return:
1493         rc = -ENOMEM;
1494
1495 free_return:    /* note that all channel pointers are 0 or valid */
1496         kfree(ch->ccw);
1497         kfree(ch->discontact_th);
1498         kfree_fsm(ch->fsm);
1499         kfree(ch->irb);
1500         kfree(ch);
1501         return rc;
1502 }
1503
1504 /*
1505  * Return type of a detected device.
1506  */
1507 static enum ctcm_channel_types get_channel_type(struct ccw_device_id *id)
1508 {
1509         enum ctcm_channel_types type;
1510         type = (enum ctcm_channel_types)id->driver_info;
1511
1512         if (type == ctcm_channel_type_ficon)
1513                 type = ctcm_channel_type_escon;
1514
1515         return type;
1516 }
1517
1518 /**
1519  *
1520  * Setup an interface.
1521  *
1522  *  cgdev       Device to be setup.
1523  *
1524  * returns 0 on success, !0 on failure.
1525  */
1526 static int ctcm_new_device(struct ccwgroup_device *cgdev)
1527 {
1528         char read_id[CTCM_ID_SIZE];
1529         char write_id[CTCM_ID_SIZE];
1530         int direction;
1531         enum ctcm_channel_types type;
1532         struct ctcm_priv *priv;
1533         struct net_device *dev;
1534         struct ccw_device *cdev0;
1535         struct ccw_device *cdev1;
1536         struct channel *readc;
1537         struct channel *writec;
1538         int ret;
1539         int result;
1540
1541         priv = dev_get_drvdata(&cgdev->dev);
1542         if (!priv) {
1543                 result = -ENODEV;
1544                 goto out_err_result;
1545         }
1546
1547         cdev0 = cgdev->cdev[0];
1548         cdev1 = cgdev->cdev[1];
1549
1550         type = get_channel_type(&cdev0->id);
1551
1552         snprintf(read_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev0->dev));
1553         snprintf(write_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev1->dev));
1554
1555         ret = add_channel(cdev0, type, priv);
1556         if (ret) {
1557                 result = ret;
1558                 goto out_err_result;
1559         }
1560         ret = add_channel(cdev1, type, priv);
1561         if (ret) {
1562                 result = ret;
1563                 goto out_remove_channel1;
1564         }
1565
1566         ret = ccw_device_set_online(cdev0);
1567         if (ret != 0) {
1568                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1569                         "%s(%s) set_online rc=%d",
1570                                 CTCM_FUNTAIL, read_id, ret);
1571                 result = -EIO;
1572                 goto out_remove_channel2;
1573         }
1574
1575         ret = ccw_device_set_online(cdev1);
1576         if (ret != 0) {
1577                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1578                         "%s(%s) set_online rc=%d",
1579                                 CTCM_FUNTAIL, write_id, ret);
1580
1581                 result = -EIO;
1582                 goto out_ccw1;
1583         }
1584
1585         dev = ctcm_init_netdevice(priv);
1586         if (dev == NULL) {
1587                 result = -ENODEV;
1588                 goto out_ccw2;
1589         }
1590
1591         for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1592                 priv->channel[direction] =
1593                         channel_get(type, direction == CTCM_READ ?
1594                                 read_id : write_id, direction);
1595                 if (priv->channel[direction] == NULL) {
1596                         if (direction == CTCM_WRITE)
1597                                 channel_free(priv->channel[CTCM_READ]);
1598                         goto out_dev;
1599                 }
1600                 priv->channel[direction]->netdev = dev;
1601                 priv->channel[direction]->protocol = priv->protocol;
1602                 priv->channel[direction]->max_bufsize = priv->buffer_size;
1603         }
1604         /* sysfs magic */
1605         SET_NETDEV_DEV(dev, &cgdev->dev);
1606
1607         if (register_netdev(dev)) {
1608                 result = -ENODEV;
1609                 goto out_dev;
1610         }
1611
1612         strlcpy(priv->fsm->name, dev->name, sizeof(priv->fsm->name));
1613
1614         dev_info(&dev->dev,
1615                 "setup OK : r/w = %s/%s, protocol : %d\n",
1616                         priv->channel[CTCM_READ]->id,
1617                         priv->channel[CTCM_WRITE]->id, priv->protocol);
1618
1619         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1620                 "setup(%s) OK : r/w = %s/%s, protocol : %d", dev->name,
1621                         priv->channel[CTCM_READ]->id,
1622                         priv->channel[CTCM_WRITE]->id, priv->protocol);
1623
1624         return 0;
1625 out_dev:
1626         ctcm_free_netdevice(dev);
1627 out_ccw2:
1628         ccw_device_set_offline(cgdev->cdev[1]);
1629 out_ccw1:
1630         ccw_device_set_offline(cgdev->cdev[0]);
1631 out_remove_channel2:
1632         readc = channel_get(type, read_id, CTCM_READ);
1633         channel_remove(readc);
1634 out_remove_channel1:
1635         writec = channel_get(type, write_id, CTCM_WRITE);
1636         channel_remove(writec);
1637 out_err_result:
1638         return result;
1639 }
1640
1641 /**
1642  * Shutdown an interface.
1643  *
1644  *  cgdev       Device to be shut down.
1645  *
1646  * returns 0 on success, !0 on failure.
1647  */
1648 static int ctcm_shutdown_device(struct ccwgroup_device *cgdev)
1649 {
1650         struct ctcm_priv *priv;
1651         struct net_device *dev;
1652
1653         priv = dev_get_drvdata(&cgdev->dev);
1654         if (!priv)
1655                 return -ENODEV;
1656
1657         if (priv->channel[CTCM_READ]) {
1658                 dev = priv->channel[CTCM_READ]->netdev;
1659                 CTCM_DBF_DEV(SETUP, dev, "");
1660                 /* Close the device */
1661                 ctcm_close(dev);
1662                 dev->flags &= ~IFF_RUNNING;
1663                 channel_free(priv->channel[CTCM_READ]);
1664         } else
1665                 dev = NULL;
1666
1667         if (priv->channel[CTCM_WRITE])
1668                 channel_free(priv->channel[CTCM_WRITE]);
1669
1670         if (dev) {
1671                 unregister_netdev(dev);
1672                 ctcm_free_netdevice(dev);
1673         }
1674
1675         if (priv->fsm)
1676                 kfree_fsm(priv->fsm);
1677
1678         ccw_device_set_offline(cgdev->cdev[1]);
1679         ccw_device_set_offline(cgdev->cdev[0]);
1680         channel_remove(priv->channel[CTCM_READ]);
1681         channel_remove(priv->channel[CTCM_WRITE]);
1682         priv->channel[CTCM_READ] = priv->channel[CTCM_WRITE] = NULL;
1683
1684         return 0;
1685
1686 }
1687
1688
1689 static void ctcm_remove_device(struct ccwgroup_device *cgdev)
1690 {
1691         struct ctcm_priv *priv = dev_get_drvdata(&cgdev->dev);
1692
1693         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1694                         "removing device %p, proto : %d",
1695                         cgdev, priv->protocol);
1696
1697         if (cgdev->state == CCWGROUP_ONLINE)
1698                 ctcm_shutdown_device(cgdev);
1699         dev_set_drvdata(&cgdev->dev, NULL);
1700         kfree(priv);
1701         put_device(&cgdev->dev);
1702 }
1703
1704 static int ctcm_pm_suspend(struct ccwgroup_device *gdev)
1705 {
1706         struct ctcm_priv *priv = dev_get_drvdata(&gdev->dev);
1707
1708         if (gdev->state == CCWGROUP_OFFLINE)
1709                 return 0;
1710         netif_device_detach(priv->channel[CTCM_READ]->netdev);
1711         ctcm_close(priv->channel[CTCM_READ]->netdev);
1712         if (!wait_event_timeout(priv->fsm->wait_q,
1713             fsm_getstate(priv->fsm) == DEV_STATE_STOPPED, CTCM_TIME_5_SEC)) {
1714                 netif_device_attach(priv->channel[CTCM_READ]->netdev);
1715                 return -EBUSY;
1716         }
1717         ccw_device_set_offline(gdev->cdev[1]);
1718         ccw_device_set_offline(gdev->cdev[0]);
1719         return 0;
1720 }
1721
1722 static int ctcm_pm_resume(struct ccwgroup_device *gdev)
1723 {
1724         struct ctcm_priv *priv = dev_get_drvdata(&gdev->dev);
1725         int rc;
1726
1727         if (gdev->state == CCWGROUP_OFFLINE)
1728                 return 0;
1729         rc = ccw_device_set_online(gdev->cdev[1]);
1730         if (rc)
1731                 goto err_out;
1732         rc = ccw_device_set_online(gdev->cdev[0]);
1733         if (rc)
1734                 goto err_out;
1735         ctcm_open(priv->channel[CTCM_READ]->netdev);
1736 err_out:
1737         netif_device_attach(priv->channel[CTCM_READ]->netdev);
1738         return rc;
1739 }
1740
1741 static struct ccw_device_id ctcm_ids[] = {
1742         {CCW_DEVICE(0x3088, 0x08), .driver_info = ctcm_channel_type_parallel},
1743         {CCW_DEVICE(0x3088, 0x1e), .driver_info = ctcm_channel_type_ficon},
1744         {CCW_DEVICE(0x3088, 0x1f), .driver_info = ctcm_channel_type_escon},
1745         {},
1746 };
1747 MODULE_DEVICE_TABLE(ccw, ctcm_ids);
1748
1749 static struct ccw_driver ctcm_ccw_driver = {
1750         .driver = {
1751                 .owner  = THIS_MODULE,
1752                 .name   = "ctcm",
1753         },
1754         .ids    = ctcm_ids,
1755         .probe  = ccwgroup_probe_ccwdev,
1756         .remove = ccwgroup_remove_ccwdev,
1757         .int_class = IRQIO_CTC,
1758 };
1759
1760 static struct ccwgroup_driver ctcm_group_driver = {
1761         .driver = {
1762                 .owner  = THIS_MODULE,
1763                 .name   = CTC_DRIVER_NAME,
1764         },
1765         .ccw_driver  = &ctcm_ccw_driver,
1766         .setup       = ctcm_probe_device,
1767         .remove      = ctcm_remove_device,
1768         .set_online  = ctcm_new_device,
1769         .set_offline = ctcm_shutdown_device,
1770         .freeze      = ctcm_pm_suspend,
1771         .thaw        = ctcm_pm_resume,
1772         .restore     = ctcm_pm_resume,
1773 };
1774
1775 static ssize_t group_store(struct device_driver *ddrv, const char *buf,
1776                            size_t count)
1777 {
1778         int err;
1779
1780         err = ccwgroup_create_dev(ctcm_root_dev, &ctcm_group_driver, 2, buf);
1781         return err ? err : count;
1782 }
1783 static DRIVER_ATTR_WO(group);
1784
1785 static struct attribute *ctcm_drv_attrs[] = {
1786         &driver_attr_group.attr,
1787         NULL,
1788 };
1789 static struct attribute_group ctcm_drv_attr_group = {
1790         .attrs = ctcm_drv_attrs,
1791 };
1792 static const struct attribute_group *ctcm_drv_attr_groups[] = {
1793         &ctcm_drv_attr_group,
1794         NULL,
1795 };
1796
1797 /*
1798  * Module related routines
1799  */
1800
1801 /*
1802  * Prepare to be unloaded. Free IRQ's and release all resources.
1803  * This is called just before this module is unloaded. It is
1804  * not called, if the usage count is !0, so we don't need to check
1805  * for that.
1806  */
1807 static void __exit ctcm_exit(void)
1808 {
1809         ccwgroup_driver_unregister(&ctcm_group_driver);
1810         ccw_driver_unregister(&ctcm_ccw_driver);
1811         root_device_unregister(ctcm_root_dev);
1812         ctcm_unregister_dbf_views();
1813         pr_info("CTCM driver unloaded\n");
1814 }
1815
1816 /*
1817  * Print Banner.
1818  */
1819 static void print_banner(void)
1820 {
1821         pr_info("CTCM driver initialized\n");
1822 }
1823
1824 /**
1825  * Initialize module.
1826  * This is called just after the module is loaded.
1827  *
1828  * returns 0 on success, !0 on error.
1829  */
1830 static int __init ctcm_init(void)
1831 {
1832         int ret;
1833
1834         channels = NULL;
1835
1836         ret = ctcm_register_dbf_views();
1837         if (ret)
1838                 goto out_err;
1839         ctcm_root_dev = root_device_register("ctcm");
1840         ret = PTR_ERR_OR_ZERO(ctcm_root_dev);
1841         if (ret)
1842                 goto register_err;
1843         ret = ccw_driver_register(&ctcm_ccw_driver);
1844         if (ret)
1845                 goto ccw_err;
1846         ctcm_group_driver.driver.groups = ctcm_drv_attr_groups;
1847         ret = ccwgroup_driver_register(&ctcm_group_driver);
1848         if (ret)
1849                 goto ccwgroup_err;
1850         print_banner();
1851         return 0;
1852
1853 ccwgroup_err:
1854         ccw_driver_unregister(&ctcm_ccw_driver);
1855 ccw_err:
1856         root_device_unregister(ctcm_root_dev);
1857 register_err:
1858         ctcm_unregister_dbf_views();
1859 out_err:
1860         pr_err("%s / Initializing the ctcm device driver failed, ret = %d\n",
1861                 __func__, ret);
1862         return ret;
1863 }
1864
1865 module_init(ctcm_init);
1866 module_exit(ctcm_exit);
1867
1868 MODULE_AUTHOR("Peter Tiedemann <ptiedem@de.ibm.com>");
1869 MODULE_DESCRIPTION("Network driver for S/390 CTC + CTCMPC (SNA)");
1870 MODULE_LICENSE("GPL");
1871