Merge tag 'v6.6-p5' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
[platform/kernel/linux-rpi.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(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 = skb_put_zero(sweep_skb, TH_SWEEP_LENGTH);
627         header->th.th_ch_flag   = TH_SWEEP_REQ;  /* 0x0f */
628         header->sw.th_last_seq  = ch->th_seq_num;
629
630         netif_trans_update(dev);
631         skb_queue_tail(&ch->sweep_queue, sweep_skb);
632
633         fsm_addtimer(&ch->sweep_timer, 100, CTC_EVENT_RSWEEP_TIMER, ch);
634
635         return;
636
637 nomem:
638         grp->in_sweep = 0;
639         ctcm_clear_busy(dev);
640         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
641
642         return;
643 }
644
645 /*
646  * MPC mode version of transmit_skb
647  */
648 static int ctcmpc_transmit_skb(struct channel *ch, struct sk_buff *skb)
649 {
650         struct pdu *p_header;
651         struct net_device *dev = ch->netdev;
652         struct ctcm_priv *priv = dev->ml_priv;
653         struct mpc_group *grp = priv->mpcg;
654         struct th_header *header;
655         struct sk_buff *nskb;
656         int rc = 0;
657         int ccw_idx;
658         unsigned long hi;
659         unsigned long saveflags = 0;    /* avoids compiler warning */
660
661         CTCM_PR_DEBUG("Enter %s: %s, cp=%i ch=0x%p id=%s state=%s\n",
662                         __func__, dev->name, smp_processor_id(), ch,
663                                         ch->id, fsm_getstate_str(ch->fsm));
664
665         if ((fsm_getstate(ch->fsm) != CTC_STATE_TXIDLE) || grp->in_sweep) {
666                 spin_lock_irqsave(&ch->collect_lock, saveflags);
667                 refcount_inc(&skb->users);
668
669                 p_header = skb_push(skb, PDU_HEADER_LENGTH);
670                 p_header->pdu_offset = skb->len - PDU_HEADER_LENGTH;
671                 p_header->pdu_proto = 0x01;
672                 if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
673                         p_header->pdu_flag = PDU_FIRST | PDU_CNTL;
674                 } else {
675                         p_header->pdu_flag = PDU_FIRST;
676                 }
677                 p_header->pdu_seq = 0;
678
679                 CTCM_PR_DEBUG("%s(%s): Put on collect_q - skb len: %04x \n"
680                                 "pdu header and data for up to 32 bytes:\n",
681                                 __func__, dev->name, skb->len);
682                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
683
684                 skb_queue_tail(&ch->collect_queue, skb);
685                 ch->collect_len += skb->len;
686
687                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
688                 goto done;
689         }
690
691         /*
692          * Protect skb against beeing free'd by upper
693          * layers.
694          */
695         refcount_inc(&skb->users);
696
697         /*
698          * IDAL support in CTCM is broken, so we have to
699          * care about skb's above 2G ourselves.
700          */
701         hi = ((unsigned long)skb->tail + TH_HEADER_LENGTH) >> 31;
702         if (hi) {
703                 nskb = __dev_alloc_skb(skb->len, GFP_ATOMIC | GFP_DMA);
704                 if (!nskb) {
705                         goto nomem_exit;
706                 } else {
707                         skb_put_data(nskb, skb->data, skb->len);
708                         refcount_inc(&nskb->users);
709                         refcount_dec(&skb->users);
710                         dev_kfree_skb_irq(skb);
711                         skb = nskb;
712                 }
713         }
714
715         p_header = skb_push(skb, PDU_HEADER_LENGTH);
716         p_header->pdu_offset = skb->len - PDU_HEADER_LENGTH;
717         p_header->pdu_proto = 0x01;
718         p_header->pdu_seq = 0;
719         if (be16_to_cpu(skb->protocol) == ETH_P_SNAP) {
720                 p_header->pdu_flag = PDU_FIRST | PDU_CNTL;
721         } else {
722                 p_header->pdu_flag = PDU_FIRST;
723         }
724
725         if (ch->collect_len > 0) {
726                 spin_lock_irqsave(&ch->collect_lock, saveflags);
727                 skb_queue_tail(&ch->collect_queue, skb);
728                 ch->collect_len += skb->len;
729                 skb = skb_dequeue(&ch->collect_queue);
730                 ch->collect_len -= skb->len;
731                 spin_unlock_irqrestore(&ch->collect_lock, saveflags);
732         }
733
734         p_header = (struct pdu *)skb->data;
735         p_header->pdu_flag |= PDU_LAST;
736
737         ch->prof.txlen += skb->len - PDU_HEADER_LENGTH;
738
739         /* put the TH on the packet */
740         header = skb_push(skb, TH_HEADER_LENGTH);
741         memset(header, 0, TH_HEADER_LENGTH);
742
743         header->th_ch_flag = TH_HAS_PDU;  /* Normal data */
744         ch->th_seq_num++;
745         header->th_seq_num = ch->th_seq_num;
746
747         CTCM_PR_DBGDATA("%s(%s) ToVTAM_th_seq= %08x\n" ,
748                        __func__, dev->name, ch->th_seq_num);
749
750         CTCM_PR_DBGDATA("%s(%s): skb len: %04x\n - pdu header and data for "
751                         "up to 32 bytes sent to vtam:\n",
752                                 __func__, dev->name, skb->len);
753         CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
754
755         ch->ccw[4].count = skb->len;
756         if (set_normalized_cda(&ch->ccw[4], skb->data)) {
757                 /*
758                  * idal allocation failed, try via copying to trans_skb.
759                  * trans_skb usually has a pre-allocated idal.
760                  */
761                 if (ctcm_checkalloc_buffer(ch)) {
762                         /*
763                          * Remove our header.
764                          * It gets added again on retransmit.
765                          */
766                                 goto nomem_exit;
767                 }
768
769                 skb_reset_tail_pointer(ch->trans_skb);
770                 ch->trans_skb->len = 0;
771                 ch->ccw[1].count = skb->len;
772                 skb_put_data(ch->trans_skb, skb->data, skb->len);
773                 refcount_dec(&skb->users);
774                 dev_kfree_skb_irq(skb);
775                 ccw_idx = 0;
776                 CTCM_PR_DBGDATA("%s(%s): trans_skb len: %04x\n"
777                                 "up to 32 bytes sent to vtam:\n",
778                                 __func__, dev->name, ch->trans_skb->len);
779                 CTCM_D3_DUMP((char *)ch->trans_skb->data,
780                                 min_t(int, 32, ch->trans_skb->len));
781         } else {
782                 skb_queue_tail(&ch->io_queue, skb);
783                 ccw_idx = 3;
784         }
785         ch->retry = 0;
786         fsm_newstate(ch->fsm, CTC_STATE_TX);
787         fsm_addtimer(&ch->timer, CTCM_TIME_5_SEC, CTC_EVENT_TIMER, ch);
788
789         if (do_debug_ccw)
790                 ctcmpc_dumpit((char *)&ch->ccw[ccw_idx],
791                                         sizeof(struct ccw1) * 3);
792
793         spin_lock_irqsave(get_ccwdev_lock(ch->cdev), saveflags);
794         ch->prof.send_stamp = jiffies;
795         rc = ccw_device_start(ch->cdev, &ch->ccw[ccw_idx], 0, 0xff, 0);
796         spin_unlock_irqrestore(get_ccwdev_lock(ch->cdev), saveflags);
797         if (ccw_idx == 3)
798                 ch->prof.doios_single++;
799         if (rc != 0) {
800                 fsm_deltimer(&ch->timer);
801                 ctcm_ccw_check_rc(ch, rc, "single skb TX");
802                 if (ccw_idx == 3)
803                         skb_dequeue_tail(&ch->io_queue);
804         } else if (ccw_idx == 0) {
805                 priv->stats.tx_packets++;
806                 priv->stats.tx_bytes += skb->len - TH_HEADER_LENGTH;
807         }
808         if (ch->th_seq_num > 0xf0000000)        /* Chose at random. */
809                 ctcmpc_send_sweep_req(ch);
810
811         goto done;
812 nomem_exit:
813         CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_CRIT,
814                         "%s(%s): MEMORY allocation ERROR\n",
815                         CTCM_FUNTAIL, ch->id);
816         rc = -ENOMEM;
817         refcount_dec(&skb->users);
818         dev_kfree_skb_any(skb);
819         fsm_event(priv->mpcg->fsm, MPCG_EVENT_INOP, dev);
820 done:
821         CTCM_PR_DEBUG("Exit %s(%s)\n", __func__, dev->name);
822         return rc;
823 }
824
825 /*
826  * Start transmission of a packet.
827  * Called from generic network device layer.
828  */
829 /* first merge version - leaving both functions separated */
830 static netdev_tx_t ctcm_tx(struct sk_buff *skb, struct net_device *dev)
831 {
832         struct ctcm_priv *priv = dev->ml_priv;
833
834         if (skb == NULL) {
835                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
836                                 "%s(%s): NULL sk_buff passed",
837                                         CTCM_FUNTAIL, dev->name);
838                 priv->stats.tx_dropped++;
839                 return NETDEV_TX_OK;
840         }
841         if (skb_headroom(skb) < (LL_HEADER_LENGTH + 2)) {
842                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
843                         "%s(%s): Got sk_buff with head room < %ld bytes",
844                         CTCM_FUNTAIL, dev->name, LL_HEADER_LENGTH + 2);
845                 dev_kfree_skb(skb);
846                 priv->stats.tx_dropped++;
847                 return NETDEV_TX_OK;
848         }
849
850         /*
851          * If channels are not running, try to restart them
852          * and throw away packet.
853          */
854         if (fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) {
855                 fsm_event(priv->fsm, DEV_EVENT_START, dev);
856                 dev_kfree_skb(skb);
857                 priv->stats.tx_dropped++;
858                 priv->stats.tx_errors++;
859                 priv->stats.tx_carrier_errors++;
860                 return NETDEV_TX_OK;
861         }
862
863         if (ctcm_test_and_set_busy(dev))
864                 return NETDEV_TX_BUSY;
865
866         netif_trans_update(dev);
867         if (ctcm_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0)
868                 return NETDEV_TX_BUSY;
869         return NETDEV_TX_OK;
870 }
871
872 /* unmerged MPC variant of ctcm_tx */
873 static netdev_tx_t ctcmpc_tx(struct sk_buff *skb, struct net_device *dev)
874 {
875         int len = 0;
876         struct ctcm_priv *priv = dev->ml_priv;
877         struct mpc_group *grp  = priv->mpcg;
878         struct sk_buff *newskb = NULL;
879
880         /*
881          * Some sanity checks ...
882          */
883         if (skb == NULL) {
884                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
885                         "%s(%s): NULL sk_buff passed",
886                                         CTCM_FUNTAIL, dev->name);
887                 priv->stats.tx_dropped++;
888                 goto done;
889         }
890         if (skb_headroom(skb) < (TH_HEADER_LENGTH + PDU_HEADER_LENGTH)) {
891                 CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
892                         "%s(%s): Got sk_buff with head room < %ld bytes",
893                         CTCM_FUNTAIL, dev->name,
894                                 TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
895
896                 CTCM_D3_DUMP((char *)skb->data, min_t(int, 32, skb->len));
897
898                 len =  skb->len + TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
899                 newskb = __dev_alloc_skb(len, GFP_ATOMIC | GFP_DMA);
900
901                 if (!newskb) {
902                         CTCM_DBF_TEXT_(MPC_TRACE, CTC_DBF_ERROR,
903                                 "%s: %s: __dev_alloc_skb failed",
904                                                 __func__, dev->name);
905
906                         dev_kfree_skb_any(skb);
907                         priv->stats.tx_dropped++;
908                         priv->stats.tx_errors++;
909                         priv->stats.tx_carrier_errors++;
910                         fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
911                         goto done;
912                 }
913                 newskb->protocol = skb->protocol;
914                 skb_reserve(newskb, TH_HEADER_LENGTH + PDU_HEADER_LENGTH);
915                 skb_put_data(newskb, skb->data, skb->len);
916                 dev_kfree_skb_any(skb);
917                 skb = newskb;
918         }
919
920         /*
921          * If channels are not running,
922          * notify anybody about a link failure and throw
923          * away packet.
924          */
925         if ((fsm_getstate(priv->fsm) != DEV_STATE_RUNNING) ||
926            (fsm_getstate(grp->fsm) <  MPCG_STATE_XID2INITW)) {
927                 dev_kfree_skb_any(skb);
928                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
929                         "%s(%s): inactive MPCGROUP - dropped",
930                                         CTCM_FUNTAIL, dev->name);
931                 priv->stats.tx_dropped++;
932                 priv->stats.tx_errors++;
933                 priv->stats.tx_carrier_errors++;
934                 goto done;
935         }
936
937         if (ctcm_test_and_set_busy(dev)) {
938                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
939                         "%s(%s): device busy - dropped",
940                                         CTCM_FUNTAIL, dev->name);
941                 dev_kfree_skb_any(skb);
942                 priv->stats.tx_dropped++;
943                 priv->stats.tx_errors++;
944                 priv->stats.tx_carrier_errors++;
945                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
946                 goto done;
947         }
948
949         netif_trans_update(dev);
950         if (ctcmpc_transmit_skb(priv->channel[CTCM_WRITE], skb) != 0) {
951                 CTCM_DBF_TEXT_(MPC_ERROR, CTC_DBF_ERROR,
952                         "%s(%s): device error - dropped",
953                                         CTCM_FUNTAIL, dev->name);
954                 dev_kfree_skb_any(skb);
955                 priv->stats.tx_dropped++;
956                 priv->stats.tx_errors++;
957                 priv->stats.tx_carrier_errors++;
958                 ctcm_clear_busy(dev);
959                 fsm_event(grp->fsm, MPCG_EVENT_INOP, dev);
960                 goto done;
961         }
962         ctcm_clear_busy(dev);
963 done:
964         if (do_debug)
965                 MPC_DBF_DEV_NAME(TRACE, dev, "exit");
966
967         return NETDEV_TX_OK;    /* handle freeing of skb here */
968 }
969
970
971 /*
972  * Sets MTU of an interface.
973  *
974  *  dev         Pointer to interface struct.
975  *  new_mtu     The new MTU to use for this interface.
976  *
977  * returns 0 on success, -EINVAL if MTU is out of valid range.
978  *         (valid range is 576 .. 65527). If VM is on the
979  *         remote side, maximum MTU is 32760, however this is
980  *         not checked here.
981  */
982 static int ctcm_change_mtu(struct net_device *dev, int new_mtu)
983 {
984         struct ctcm_priv *priv;
985         int max_bufsize;
986
987         priv = dev->ml_priv;
988         max_bufsize = priv->channel[CTCM_READ]->max_bufsize;
989
990         if (IS_MPC(priv)) {
991                 if (new_mtu > max_bufsize - TH_HEADER_LENGTH)
992                         return -EINVAL;
993                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
994         } else {
995                 if (new_mtu > max_bufsize - LL_HEADER_LENGTH - 2)
996                         return -EINVAL;
997                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
998         }
999         dev->mtu = new_mtu;
1000         return 0;
1001 }
1002
1003 /*
1004  * Returns interface statistics of a device.
1005  *
1006  *  dev         Pointer to interface struct.
1007  *
1008  * returns Pointer to stats struct of this interface.
1009  */
1010 static struct net_device_stats *ctcm_stats(struct net_device *dev)
1011 {
1012         return &((struct ctcm_priv *)dev->ml_priv)->stats;
1013 }
1014
1015 static void ctcm_free_netdevice(struct net_device *dev)
1016 {
1017         struct ctcm_priv *priv;
1018         struct mpc_group *grp;
1019
1020         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1021                         "%s(%s)", CTCM_FUNTAIL, dev->name);
1022         priv = dev->ml_priv;
1023         if (priv) {
1024                 grp = priv->mpcg;
1025                 if (grp) {
1026                         if (grp->fsm)
1027                                 kfree_fsm(grp->fsm);
1028                         dev_kfree_skb(grp->xid_skb);
1029                         dev_kfree_skb(grp->rcvd_xid_skb);
1030                         tasklet_kill(&grp->mpc_tasklet2);
1031                         kfree(grp);
1032                         priv->mpcg = NULL;
1033                 }
1034                 if (priv->fsm) {
1035                         kfree_fsm(priv->fsm);
1036                         priv->fsm = NULL;
1037                 }
1038                 kfree(priv->xid);
1039                 priv->xid = NULL;
1040         /*
1041          * Note: kfree(priv); is done in "opposite" function of
1042          * allocator function probe_device which is remove_device.
1043          */
1044         }
1045 #ifdef MODULE
1046         free_netdev(dev);
1047 #endif
1048 }
1049
1050 struct mpc_group *ctcmpc_init_mpc_group(struct ctcm_priv *priv);
1051
1052 static const struct net_device_ops ctcm_netdev_ops = {
1053         .ndo_open               = ctcm_open,
1054         .ndo_stop               = ctcm_close,
1055         .ndo_get_stats          = ctcm_stats,
1056         .ndo_change_mtu         = ctcm_change_mtu,
1057         .ndo_start_xmit         = ctcm_tx,
1058 };
1059
1060 static const struct net_device_ops ctcm_mpc_netdev_ops = {
1061         .ndo_open               = ctcm_open,
1062         .ndo_stop               = ctcm_close,
1063         .ndo_get_stats          = ctcm_stats,
1064         .ndo_change_mtu         = ctcm_change_mtu,
1065         .ndo_start_xmit         = ctcmpc_tx,
1066 };
1067
1068 static void ctcm_dev_setup(struct net_device *dev)
1069 {
1070         dev->type = ARPHRD_SLIP;
1071         dev->tx_queue_len = 100;
1072         dev->flags = IFF_POINTOPOINT | IFF_NOARP;
1073         dev->min_mtu = 576;
1074         dev->max_mtu = 65527;
1075 }
1076
1077 /*
1078  * Initialize everything of the net device except the name and the
1079  * channel structs.
1080  */
1081 static struct net_device *ctcm_init_netdevice(struct ctcm_priv *priv)
1082 {
1083         struct net_device *dev;
1084         struct mpc_group *grp;
1085         if (!priv)
1086                 return NULL;
1087
1088         if (IS_MPC(priv))
1089                 dev = alloc_netdev(0, MPC_DEVICE_GENE, NET_NAME_UNKNOWN,
1090                                    ctcm_dev_setup);
1091         else
1092                 dev = alloc_netdev(0, CTC_DEVICE_GENE, NET_NAME_UNKNOWN,
1093                                    ctcm_dev_setup);
1094
1095         if (!dev) {
1096                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_CRIT,
1097                         "%s: MEMORY allocation ERROR",
1098                         CTCM_FUNTAIL);
1099                 return NULL;
1100         }
1101         dev->ml_priv = priv;
1102         priv->fsm = init_fsm("ctcmdev", dev_state_names, dev_event_names,
1103                                 CTCM_NR_DEV_STATES, CTCM_NR_DEV_EVENTS,
1104                                 dev_fsm, dev_fsm_len, GFP_KERNEL);
1105         if (priv->fsm == NULL) {
1106                 CTCMY_DBF_DEV(SETUP, dev, "init_fsm error");
1107                 free_netdev(dev);
1108                 return NULL;
1109         }
1110         fsm_newstate(priv->fsm, DEV_STATE_STOPPED);
1111         fsm_settimer(priv->fsm, &priv->restart_timer);
1112
1113         if (IS_MPC(priv)) {
1114                 /*  MPC Group Initializations  */
1115                 grp = ctcmpc_init_mpc_group(priv);
1116                 if (grp == NULL) {
1117                         MPC_DBF_DEV(SETUP, dev, "init_mpc_group error");
1118                         free_netdev(dev);
1119                         return NULL;
1120                 }
1121                 tasklet_init(&grp->mpc_tasklet2,
1122                                 mpc_group_ready, (unsigned long)dev);
1123                 dev->mtu = MPC_BUFSIZE_DEFAULT -
1124                                 TH_HEADER_LENGTH - PDU_HEADER_LENGTH;
1125
1126                 dev->netdev_ops = &ctcm_mpc_netdev_ops;
1127                 dev->hard_header_len = TH_HEADER_LENGTH + PDU_HEADER_LENGTH;
1128                 priv->buffer_size = MPC_BUFSIZE_DEFAULT;
1129         } else {
1130                 dev->mtu = CTCM_BUFSIZE_DEFAULT - LL_HEADER_LENGTH - 2;
1131                 dev->netdev_ops = &ctcm_netdev_ops;
1132                 dev->hard_header_len = LL_HEADER_LENGTH + 2;
1133         }
1134
1135         CTCMY_DBF_DEV(SETUP, dev, "finished");
1136
1137         return dev;
1138 }
1139
1140 /*
1141  * Main IRQ handler.
1142  *
1143  *  cdev        The ccw_device the interrupt is for.
1144  *  intparm     interruption parameter.
1145  *  irb         interruption response block.
1146  */
1147 static void ctcm_irq_handler(struct ccw_device *cdev,
1148                                 unsigned long intparm, struct irb *irb)
1149 {
1150         struct channel          *ch;
1151         struct net_device       *dev;
1152         struct ctcm_priv        *priv;
1153         struct ccwgroup_device  *cgdev;
1154         int cstat;
1155         int dstat;
1156
1157         CTCM_DBF_TEXT_(TRACE, CTC_DBF_DEBUG,
1158                 "Enter %s(%s)", CTCM_FUNTAIL, dev_name(&cdev->dev));
1159
1160         if (ctcm_check_irb_error(cdev, irb))
1161                 return;
1162
1163         cgdev = dev_get_drvdata(&cdev->dev);
1164
1165         cstat = irb->scsw.cmd.cstat;
1166         dstat = irb->scsw.cmd.dstat;
1167
1168         /* Check for unsolicited interrupts. */
1169         if (cgdev == NULL) {
1170                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_ERROR,
1171                         "%s(%s) unsolicited irq: c-%02x d-%02x\n",
1172                         CTCM_FUNTAIL, dev_name(&cdev->dev), cstat, dstat);
1173                 dev_warn(&cdev->dev,
1174                         "The adapter received a non-specific IRQ\n");
1175                 return;
1176         }
1177
1178         priv = dev_get_drvdata(&cgdev->dev);
1179
1180         /* Try to extract channel from driver data. */
1181         if (priv->channel[CTCM_READ]->cdev == cdev)
1182                 ch = priv->channel[CTCM_READ];
1183         else if (priv->channel[CTCM_WRITE]->cdev == cdev)
1184                 ch = priv->channel[CTCM_WRITE];
1185         else {
1186                 dev_err(&cdev->dev,
1187                         "%s: Internal error: Can't determine channel for "
1188                         "interrupt device %s\n",
1189                         __func__, dev_name(&cdev->dev));
1190                         /* Explain: inconsistent internal structures */
1191                 return;
1192         }
1193
1194         dev = ch->netdev;
1195         if (dev == NULL) {
1196                 dev_err(&cdev->dev,
1197                         "%s Internal error: net_device is NULL, ch = 0x%p\n",
1198                         __func__, ch);
1199                         /* Explain: inconsistent internal structures */
1200                 return;
1201         }
1202
1203         /* Copy interruption response block. */
1204         memcpy(ch->irb, irb, sizeof(struct irb));
1205
1206         /* Issue error message and return on subchannel error code */
1207         if (irb->scsw.cmd.cstat) {
1208                 fsm_event(ch->fsm, CTC_EVENT_SC_UNKNOWN, ch);
1209                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1210                         "%s(%s): sub-ch check %s: cs=%02x ds=%02x",
1211                                 CTCM_FUNTAIL, dev->name, ch->id, cstat, dstat);
1212                 dev_warn(&cdev->dev,
1213                                 "A check occurred on the subchannel\n");
1214                 return;
1215         }
1216
1217         /* Check the reason-code of a unit check */
1218         if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) {
1219                 if ((irb->ecw[0] & ch->sense_rc) == 0)
1220                         /* print it only once */
1221                         CTCM_DBF_TEXT_(TRACE, CTC_DBF_WARN,
1222                                 "%s(%s): sense=%02x, ds=%02x",
1223                                 CTCM_FUNTAIL, ch->id, irb->ecw[0], dstat);
1224                 ccw_unit_check(ch, irb->ecw[0]);
1225                 return;
1226         }
1227         if (irb->scsw.cmd.dstat & DEV_STAT_BUSY) {
1228                 if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION)
1229                         fsm_event(ch->fsm, CTC_EVENT_ATTNBUSY, ch);
1230                 else
1231                         fsm_event(ch->fsm, CTC_EVENT_BUSY, ch);
1232                 return;
1233         }
1234         if (irb->scsw.cmd.dstat & DEV_STAT_ATTENTION) {
1235                 fsm_event(ch->fsm, CTC_EVENT_ATTN, ch);
1236                 return;
1237         }
1238         if ((irb->scsw.cmd.stctl & SCSW_STCTL_SEC_STATUS) ||
1239             (irb->scsw.cmd.stctl == SCSW_STCTL_STATUS_PEND) ||
1240             (irb->scsw.cmd.stctl ==
1241              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)))
1242                 fsm_event(ch->fsm, CTC_EVENT_FINSTAT, ch);
1243         else
1244                 fsm_event(ch->fsm, CTC_EVENT_IRQ, ch);
1245
1246 }
1247
1248 static const struct device_type ctcm_devtype = {
1249         .name = "ctcm",
1250         .groups = ctcm_attr_groups,
1251 };
1252
1253 /*
1254  * Add ctcm specific attributes.
1255  * Add ctcm private data.
1256  *
1257  *  cgdev       pointer to ccwgroup_device just added
1258  *
1259  * returns 0 on success, !0 on failure.
1260  */
1261 static int ctcm_probe_device(struct ccwgroup_device *cgdev)
1262 {
1263         struct ctcm_priv *priv;
1264
1265         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1266                         "%s %p",
1267                         __func__, cgdev);
1268
1269         if (!get_device(&cgdev->dev))
1270                 return -ENODEV;
1271
1272         priv = kzalloc(sizeof(struct ctcm_priv), GFP_KERNEL);
1273         if (!priv) {
1274                 CTCM_DBF_TEXT_(ERROR, CTC_DBF_ERROR,
1275                         "%s: memory allocation failure",
1276                         CTCM_FUNTAIL);
1277                 put_device(&cgdev->dev);
1278                 return -ENOMEM;
1279         }
1280         priv->buffer_size = CTCM_BUFSIZE_DEFAULT;
1281         cgdev->cdev[0]->handler = ctcm_irq_handler;
1282         cgdev->cdev[1]->handler = ctcm_irq_handler;
1283         dev_set_drvdata(&cgdev->dev, priv);
1284         cgdev->dev.type = &ctcm_devtype;
1285
1286         return 0;
1287 }
1288
1289 /*
1290  * Add a new channel to the list of channels.
1291  * Keeps the channel list sorted.
1292  *
1293  *  cdev        The ccw_device to be added.
1294  *  type        The type class of the new channel.
1295  *  priv        Points to the private data of the ccwgroup_device.
1296  *
1297  * returns 0 on success, !0 on error.
1298  */
1299 static int add_channel(struct ccw_device *cdev, enum ctcm_channel_types type,
1300                                 struct ctcm_priv *priv)
1301 {
1302         struct channel **c = &channels;
1303         struct channel *ch;
1304         int ccw_num;
1305         int rc = 0;
1306
1307         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1308                 "%s(%s), type %d, proto %d",
1309                         __func__, dev_name(&cdev->dev), type, priv->protocol);
1310
1311         ch = kzalloc(sizeof(struct channel), GFP_KERNEL);
1312         if (ch == NULL)
1313                 return -ENOMEM;
1314
1315         ch->protocol = priv->protocol;
1316         if (IS_MPC(priv)) {
1317                 ch->discontact_th = kzalloc(TH_HEADER_LENGTH, GFP_KERNEL);
1318                 if (ch->discontact_th == NULL)
1319                                         goto nomem_return;
1320
1321                 ch->discontact_th->th_blk_flag = TH_DISCONTACT;
1322                 tasklet_init(&ch->ch_disc_tasklet,
1323                         mpc_action_send_discontact, (unsigned long)ch);
1324
1325                 tasklet_init(&ch->ch_tasklet, ctcmpc_bh, (unsigned long)ch);
1326                 ch->max_bufsize = (MPC_BUFSIZE_DEFAULT - 35);
1327                 ccw_num = 17;
1328         } else
1329                 ccw_num = 8;
1330
1331         ch->ccw = kcalloc(ccw_num, sizeof(struct ccw1), GFP_KERNEL | GFP_DMA);
1332         if (ch->ccw == NULL)
1333                                         goto nomem_return;
1334
1335         ch->cdev = cdev;
1336         scnprintf(ch->id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev->dev));
1337         ch->type = type;
1338
1339         /*
1340          * "static" ccws are used in the following way:
1341          *
1342          * ccw[0..2] (Channel program for generic I/O):
1343          *           0: prepare
1344          *           1: read or write (depending on direction) with fixed
1345          *              buffer (idal allocated once when buffer is allocated)
1346          *           2: nop
1347          * ccw[3..5] (Channel program for direct write of packets)
1348          *           3: prepare
1349          *           4: write (idal allocated on every write).
1350          *           5: nop
1351          * ccw[6..7] (Channel program for initial channel setup):
1352          *           6: set extended mode
1353          *           7: nop
1354          *
1355          * ch->ccw[0..5] are initialized in ch_action_start because
1356          * the channel's direction is yet unknown here.
1357          *
1358          * ccws used for xid2 negotiations
1359          *  ch-ccw[8-14] need to be used for the XID exchange either
1360          *    X side XID2 Processing
1361          *       8:  write control
1362          *       9:  write th
1363          *           10: write XID
1364          *           11: read th from secondary
1365          *           12: read XID   from secondary
1366          *           13: read 4 byte ID
1367          *           14: nop
1368          *    Y side XID Processing
1369          *           8:  sense
1370          *       9:  read th
1371          *           10: read XID
1372          *           11: write th
1373          *           12: write XID
1374          *           13: write 4 byte ID
1375          *           14: nop
1376          *
1377          *  ccws used for double noop due to VM timing issues
1378          *  which result in unrecoverable Busy on channel
1379          *       15: nop
1380          *       16: nop
1381          */
1382         ch->ccw[6].cmd_code     = CCW_CMD_SET_EXTENDED;
1383         ch->ccw[6].flags        = CCW_FLAG_SLI;
1384
1385         ch->ccw[7].cmd_code     = CCW_CMD_NOOP;
1386         ch->ccw[7].flags        = CCW_FLAG_SLI;
1387
1388         if (IS_MPC(priv)) {
1389                 ch->ccw[15].cmd_code = CCW_CMD_WRITE;
1390                 ch->ccw[15].flags    = CCW_FLAG_SLI | CCW_FLAG_CC;
1391                 ch->ccw[15].count    = TH_HEADER_LENGTH;
1392                 ch->ccw[15].cda      = virt_to_phys(ch->discontact_th);
1393
1394                 ch->ccw[16].cmd_code = CCW_CMD_NOOP;
1395                 ch->ccw[16].flags    = CCW_FLAG_SLI;
1396
1397                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1398                                 ctc_ch_event_names, CTC_MPC_NR_STATES,
1399                                 CTC_MPC_NR_EVENTS, ctcmpc_ch_fsm,
1400                                 mpc_ch_fsm_len, GFP_KERNEL);
1401         } else {
1402                 ch->fsm = init_fsm(ch->id, ctc_ch_state_names,
1403                                 ctc_ch_event_names, CTC_NR_STATES,
1404                                 CTC_NR_EVENTS, ch_fsm,
1405                                 ch_fsm_len, GFP_KERNEL);
1406         }
1407         if (ch->fsm == NULL)
1408                                 goto nomem_return;
1409
1410         fsm_newstate(ch->fsm, CTC_STATE_IDLE);
1411
1412         ch->irb = kzalloc(sizeof(struct irb), GFP_KERNEL);
1413         if (ch->irb == NULL)
1414                                 goto nomem_return;
1415
1416         while (*c && ctcm_less_than((*c)->id, ch->id))
1417                 c = &(*c)->next;
1418
1419         if (*c && (!strncmp((*c)->id, ch->id, CTCM_ID_SIZE))) {
1420                 CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1421                                 "%s (%s) already in list, using old entry",
1422                                 __func__, (*c)->id);
1423
1424                 goto free_return;
1425         }
1426
1427         spin_lock_init(&ch->collect_lock);
1428
1429         fsm_settimer(ch->fsm, &ch->timer);
1430         skb_queue_head_init(&ch->io_queue);
1431         skb_queue_head_init(&ch->collect_queue);
1432
1433         if (IS_MPC(priv)) {
1434                 fsm_settimer(ch->fsm, &ch->sweep_timer);
1435                 skb_queue_head_init(&ch->sweep_queue);
1436         }
1437         ch->next = *c;
1438         *c = ch;
1439         return 0;
1440
1441 nomem_return:
1442         rc = -ENOMEM;
1443
1444 free_return:    /* note that all channel pointers are 0 or valid */
1445         kfree(ch->ccw);
1446         kfree(ch->discontact_th);
1447         kfree_fsm(ch->fsm);
1448         kfree(ch->irb);
1449         kfree(ch);
1450         return rc;
1451 }
1452
1453 /*
1454  * Return type of a detected device.
1455  */
1456 static enum ctcm_channel_types get_channel_type(struct ccw_device_id *id)
1457 {
1458         enum ctcm_channel_types type;
1459         type = (enum ctcm_channel_types)id->driver_info;
1460
1461         if (type == ctcm_channel_type_ficon)
1462                 type = ctcm_channel_type_escon;
1463
1464         return type;
1465 }
1466
1467 /*
1468  *
1469  * Setup an interface.
1470  *
1471  *  cgdev       Device to be setup.
1472  *
1473  * returns 0 on success, !0 on failure.
1474  */
1475 static int ctcm_new_device(struct ccwgroup_device *cgdev)
1476 {
1477         char read_id[CTCM_ID_SIZE];
1478         char write_id[CTCM_ID_SIZE];
1479         int direction;
1480         enum ctcm_channel_types type;
1481         struct ctcm_priv *priv;
1482         struct net_device *dev;
1483         struct ccw_device *cdev0;
1484         struct ccw_device *cdev1;
1485         struct channel *readc;
1486         struct channel *writec;
1487         int ret;
1488         int result;
1489
1490         priv = dev_get_drvdata(&cgdev->dev);
1491         if (!priv) {
1492                 result = -ENODEV;
1493                 goto out_err_result;
1494         }
1495
1496         cdev0 = cgdev->cdev[0];
1497         cdev1 = cgdev->cdev[1];
1498
1499         type = get_channel_type(&cdev0->id);
1500
1501         scnprintf(read_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev0->dev));
1502         scnprintf(write_id, CTCM_ID_SIZE, "ch-%s", dev_name(&cdev1->dev));
1503
1504         ret = add_channel(cdev0, type, priv);
1505         if (ret) {
1506                 result = ret;
1507                 goto out_err_result;
1508         }
1509         ret = add_channel(cdev1, type, priv);
1510         if (ret) {
1511                 result = ret;
1512                 goto out_remove_channel1;
1513         }
1514
1515         ret = ccw_device_set_online(cdev0);
1516         if (ret != 0) {
1517                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1518                         "%s(%s) set_online rc=%d",
1519                                 CTCM_FUNTAIL, read_id, ret);
1520                 result = -EIO;
1521                 goto out_remove_channel2;
1522         }
1523
1524         ret = ccw_device_set_online(cdev1);
1525         if (ret != 0) {
1526                 CTCM_DBF_TEXT_(TRACE, CTC_DBF_NOTICE,
1527                         "%s(%s) set_online rc=%d",
1528                                 CTCM_FUNTAIL, write_id, ret);
1529
1530                 result = -EIO;
1531                 goto out_ccw1;
1532         }
1533
1534         dev = ctcm_init_netdevice(priv);
1535         if (dev == NULL) {
1536                 result = -ENODEV;
1537                 goto out_ccw2;
1538         }
1539
1540         for (direction = CTCM_READ; direction <= CTCM_WRITE; direction++) {
1541                 priv->channel[direction] =
1542                         channel_get(type, direction == CTCM_READ ?
1543                                 read_id : write_id, direction);
1544                 if (priv->channel[direction] == NULL) {
1545                         if (direction == CTCM_WRITE)
1546                                 channel_free(priv->channel[CTCM_READ]);
1547                         result = -ENODEV;
1548                         goto out_dev;
1549                 }
1550                 priv->channel[direction]->netdev = dev;
1551                 priv->channel[direction]->protocol = priv->protocol;
1552                 priv->channel[direction]->max_bufsize = priv->buffer_size;
1553         }
1554         /* sysfs magic */
1555         SET_NETDEV_DEV(dev, &cgdev->dev);
1556
1557         if (register_netdev(dev)) {
1558                 result = -ENODEV;
1559                 goto out_dev;
1560         }
1561
1562         strscpy(priv->fsm->name, dev->name, sizeof(priv->fsm->name));
1563
1564         dev_info(&dev->dev,
1565                 "setup OK : r/w = %s/%s, protocol : %d\n",
1566                         priv->channel[CTCM_READ]->id,
1567                         priv->channel[CTCM_WRITE]->id, priv->protocol);
1568
1569         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1570                 "setup(%s) OK : r/w = %s/%s, protocol : %d", dev->name,
1571                         priv->channel[CTCM_READ]->id,
1572                         priv->channel[CTCM_WRITE]->id, priv->protocol);
1573
1574         return 0;
1575 out_dev:
1576         ctcm_free_netdevice(dev);
1577 out_ccw2:
1578         ccw_device_set_offline(cgdev->cdev[1]);
1579 out_ccw1:
1580         ccw_device_set_offline(cgdev->cdev[0]);
1581 out_remove_channel2:
1582         readc = channel_get(type, read_id, CTCM_READ);
1583         channel_remove(readc);
1584 out_remove_channel1:
1585         writec = channel_get(type, write_id, CTCM_WRITE);
1586         channel_remove(writec);
1587 out_err_result:
1588         return result;
1589 }
1590
1591 /*
1592  * Shutdown an interface.
1593  *
1594  *  cgdev       Device to be shut down.
1595  *
1596  * returns 0 on success, !0 on failure.
1597  */
1598 static int ctcm_shutdown_device(struct ccwgroup_device *cgdev)
1599 {
1600         struct ctcm_priv *priv;
1601         struct net_device *dev;
1602
1603         priv = dev_get_drvdata(&cgdev->dev);
1604         if (!priv)
1605                 return -ENODEV;
1606
1607         if (priv->channel[CTCM_READ]) {
1608                 dev = priv->channel[CTCM_READ]->netdev;
1609                 CTCM_DBF_DEV(SETUP, dev, "");
1610                 /* Close the device */
1611                 ctcm_close(dev);
1612                 dev->flags &= ~IFF_RUNNING;
1613                 channel_free(priv->channel[CTCM_READ]);
1614         } else
1615                 dev = NULL;
1616
1617         if (priv->channel[CTCM_WRITE])
1618                 channel_free(priv->channel[CTCM_WRITE]);
1619
1620         if (dev) {
1621                 unregister_netdev(dev);
1622                 ctcm_free_netdevice(dev);
1623         }
1624
1625         if (priv->fsm)
1626                 kfree_fsm(priv->fsm);
1627
1628         ccw_device_set_offline(cgdev->cdev[1]);
1629         ccw_device_set_offline(cgdev->cdev[0]);
1630         channel_remove(priv->channel[CTCM_READ]);
1631         channel_remove(priv->channel[CTCM_WRITE]);
1632         priv->channel[CTCM_READ] = priv->channel[CTCM_WRITE] = NULL;
1633
1634         return 0;
1635
1636 }
1637
1638
1639 static void ctcm_remove_device(struct ccwgroup_device *cgdev)
1640 {
1641         struct ctcm_priv *priv = dev_get_drvdata(&cgdev->dev);
1642
1643         CTCM_DBF_TEXT_(SETUP, CTC_DBF_INFO,
1644                         "removing device %p, proto : %d",
1645                         cgdev, priv->protocol);
1646
1647         if (cgdev->state == CCWGROUP_ONLINE)
1648                 ctcm_shutdown_device(cgdev);
1649         dev_set_drvdata(&cgdev->dev, NULL);
1650         kfree(priv);
1651         put_device(&cgdev->dev);
1652 }
1653
1654 static struct ccw_device_id ctcm_ids[] = {
1655         {CCW_DEVICE(0x3088, 0x08), .driver_info = ctcm_channel_type_parallel},
1656         {CCW_DEVICE(0x3088, 0x1e), .driver_info = ctcm_channel_type_ficon},
1657         {CCW_DEVICE(0x3088, 0x1f), .driver_info = ctcm_channel_type_escon},
1658         {},
1659 };
1660 MODULE_DEVICE_TABLE(ccw, ctcm_ids);
1661
1662 static struct ccw_driver ctcm_ccw_driver = {
1663         .driver = {
1664                 .owner  = THIS_MODULE,
1665                 .name   = "ctcm",
1666         },
1667         .ids    = ctcm_ids,
1668         .probe  = ccwgroup_probe_ccwdev,
1669         .remove = ccwgroup_remove_ccwdev,
1670         .int_class = IRQIO_CTC,
1671 };
1672
1673 static struct ccwgroup_driver ctcm_group_driver = {
1674         .driver = {
1675                 .owner  = THIS_MODULE,
1676                 .name   = CTC_DRIVER_NAME,
1677         },
1678         .ccw_driver  = &ctcm_ccw_driver,
1679         .setup       = ctcm_probe_device,
1680         .remove      = ctcm_remove_device,
1681         .set_online  = ctcm_new_device,
1682         .set_offline = ctcm_shutdown_device,
1683 };
1684
1685 static ssize_t group_store(struct device_driver *ddrv, const char *buf,
1686                            size_t count)
1687 {
1688         int err;
1689
1690         err = ccwgroup_create_dev(ctcm_root_dev, &ctcm_group_driver, 2, buf);
1691         return err ? err : count;
1692 }
1693 static DRIVER_ATTR_WO(group);
1694
1695 static struct attribute *ctcm_drv_attrs[] = {
1696         &driver_attr_group.attr,
1697         NULL,
1698 };
1699 static struct attribute_group ctcm_drv_attr_group = {
1700         .attrs = ctcm_drv_attrs,
1701 };
1702 static const struct attribute_group *ctcm_drv_attr_groups[] = {
1703         &ctcm_drv_attr_group,
1704         NULL,
1705 };
1706
1707 /*
1708  * Module related routines
1709  */
1710
1711 /*
1712  * Prepare to be unloaded. Free IRQ's and release all resources.
1713  * This is called just before this module is unloaded. It is
1714  * not called, if the usage count is !0, so we don't need to check
1715  * for that.
1716  */
1717 static void __exit ctcm_exit(void)
1718 {
1719         ccwgroup_driver_unregister(&ctcm_group_driver);
1720         ccw_driver_unregister(&ctcm_ccw_driver);
1721         root_device_unregister(ctcm_root_dev);
1722         ctcm_unregister_dbf_views();
1723         pr_info("CTCM driver unloaded\n");
1724 }
1725
1726 /*
1727  * Print Banner.
1728  */
1729 static void print_banner(void)
1730 {
1731         pr_info("CTCM driver initialized\n");
1732 }
1733
1734 /*
1735  * Initialize module.
1736  * This is called just after the module is loaded.
1737  *
1738  * returns 0 on success, !0 on error.
1739  */
1740 static int __init ctcm_init(void)
1741 {
1742         int ret;
1743
1744         channels = NULL;
1745
1746         ret = ctcm_register_dbf_views();
1747         if (ret)
1748                 goto out_err;
1749         ctcm_root_dev = root_device_register("ctcm");
1750         ret = PTR_ERR_OR_ZERO(ctcm_root_dev);
1751         if (ret)
1752                 goto register_err;
1753         ret = ccw_driver_register(&ctcm_ccw_driver);
1754         if (ret)
1755                 goto ccw_err;
1756         ctcm_group_driver.driver.groups = ctcm_drv_attr_groups;
1757         ret = ccwgroup_driver_register(&ctcm_group_driver);
1758         if (ret)
1759                 goto ccwgroup_err;
1760         print_banner();
1761         return 0;
1762
1763 ccwgroup_err:
1764         ccw_driver_unregister(&ctcm_ccw_driver);
1765 ccw_err:
1766         root_device_unregister(ctcm_root_dev);
1767 register_err:
1768         ctcm_unregister_dbf_views();
1769 out_err:
1770         pr_err("%s / Initializing the ctcm device driver failed, ret = %d\n",
1771                 __func__, ret);
1772         return ret;
1773 }
1774
1775 module_init(ctcm_init);
1776 module_exit(ctcm_exit);
1777
1778 MODULE_AUTHOR("Peter Tiedemann <ptiedem@de.ibm.com>");
1779 MODULE_DESCRIPTION("Network driver for S/390 CTC + CTCMPC (SNA)");
1780 MODULE_LICENSE("GPL");
1781