xref: /openbmc/linux/drivers/s390/net/netiucv.c (revision 9cfc5c90)
1 /*
2  * IUCV network driver
3  *
4  * Copyright IBM Corp. 2001, 2009
5  *
6  * Author(s):
7  *	Original netiucv driver:
8  *		Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
9  *	Sysfs integration and all bugs therein:
10  *		Cornelia Huck (cornelia.huck@de.ibm.com)
11  *	PM functions:
12  *		Ursula Braun (ursula.braun@de.ibm.com)
13  *
14  * Documentation used:
15  *  the source of the original IUCV driver by:
16  *    Stefan Hegewald <hegewald@de.ibm.com>
17  *    Hartmut Penner <hpenner@de.ibm.com>
18  *    Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
19  *    Martin Schwidefsky (schwidefsky@de.ibm.com)
20  *    Alan Altmark (Alan_Altmark@us.ibm.com)  Sept. 2000
21  *
22  * This program is free software; you can redistribute it and/or modify
23  * it under the terms of the GNU General Public License as published by
24  * the Free Software Foundation; either version 2, or (at your option)
25  * any later version.
26  *
27  * This program is distributed in the hope that it will be useful,
28  * but WITHOUT ANY WARRANTY; without even the implied warranty of
29  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
30  * GNU General Public License for more details.
31  *
32  * You should have received a copy of the GNU General Public License
33  * along with this program; if not, write to the Free Software
34  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
35  *
36  */
37 
38 #define KMSG_COMPONENT "netiucv"
39 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
40 
41 #undef DEBUG
42 
43 #include <linux/module.h>
44 #include <linux/init.h>
45 #include <linux/kernel.h>
46 #include <linux/slab.h>
47 #include <linux/errno.h>
48 #include <linux/types.h>
49 #include <linux/interrupt.h>
50 #include <linux/timer.h>
51 #include <linux/bitops.h>
52 
53 #include <linux/signal.h>
54 #include <linux/string.h>
55 #include <linux/device.h>
56 
57 #include <linux/ip.h>
58 #include <linux/if_arp.h>
59 #include <linux/tcp.h>
60 #include <linux/skbuff.h>
61 #include <linux/ctype.h>
62 #include <net/dst.h>
63 
64 #include <asm/io.h>
65 #include <asm/uaccess.h>
66 #include <asm/ebcdic.h>
67 
68 #include <net/iucv/iucv.h>
69 #include "fsm.h"
70 
71 MODULE_AUTHOR
72     ("(C) 2001 IBM Corporation by Fritz Elfert (felfert@millenux.com)");
73 MODULE_DESCRIPTION ("Linux for S/390 IUCV network driver");
74 
75 /**
76  * Debug Facility stuff
77  */
78 #define IUCV_DBF_SETUP_NAME "iucv_setup"
79 #define IUCV_DBF_SETUP_LEN 64
80 #define IUCV_DBF_SETUP_PAGES 2
81 #define IUCV_DBF_SETUP_NR_AREAS 1
82 #define IUCV_DBF_SETUP_LEVEL 3
83 
84 #define IUCV_DBF_DATA_NAME "iucv_data"
85 #define IUCV_DBF_DATA_LEN 128
86 #define IUCV_DBF_DATA_PAGES 2
87 #define IUCV_DBF_DATA_NR_AREAS 1
88 #define IUCV_DBF_DATA_LEVEL 2
89 
90 #define IUCV_DBF_TRACE_NAME "iucv_trace"
91 #define IUCV_DBF_TRACE_LEN 16
92 #define IUCV_DBF_TRACE_PAGES 4
93 #define IUCV_DBF_TRACE_NR_AREAS 1
94 #define IUCV_DBF_TRACE_LEVEL 3
95 
96 #define IUCV_DBF_TEXT(name,level,text) \
97 	do { \
98 		debug_text_event(iucv_dbf_##name,level,text); \
99 	} while (0)
100 
101 #define IUCV_DBF_HEX(name,level,addr,len) \
102 	do { \
103 		debug_event(iucv_dbf_##name,level,(void*)(addr),len); \
104 	} while (0)
105 
106 DECLARE_PER_CPU(char[256], iucv_dbf_txt_buf);
107 
108 #define IUCV_DBF_TEXT_(name, level, text...) \
109 	do { \
110 		if (debug_level_enabled(iucv_dbf_##name, level)) { \
111 			char* __buf = get_cpu_var(iucv_dbf_txt_buf); \
112 			sprintf(__buf, text); \
113 			debug_text_event(iucv_dbf_##name, level, __buf); \
114 			put_cpu_var(iucv_dbf_txt_buf); \
115 		} \
116 	} while (0)
117 
118 #define IUCV_DBF_SPRINTF(name,level,text...) \
119 	do { \
120 		debug_sprintf_event(iucv_dbf_trace, level, ##text ); \
121 		debug_sprintf_event(iucv_dbf_trace, level, text ); \
122 	} while (0)
123 
124 /**
125  * some more debug stuff
126  */
127 #define PRINTK_HEADER " iucv: "       /* for debugging */
128 
129 /* dummy device to make sure netiucv_pm functions are called */
130 static struct device *netiucv_dev;
131 
132 static int netiucv_pm_prepare(struct device *);
133 static void netiucv_pm_complete(struct device *);
134 static int netiucv_pm_freeze(struct device *);
135 static int netiucv_pm_restore_thaw(struct device *);
136 
137 static const struct dev_pm_ops netiucv_pm_ops = {
138 	.prepare = netiucv_pm_prepare,
139 	.complete = netiucv_pm_complete,
140 	.freeze = netiucv_pm_freeze,
141 	.thaw = netiucv_pm_restore_thaw,
142 	.restore = netiucv_pm_restore_thaw,
143 };
144 
145 static struct device_driver netiucv_driver = {
146 	.owner = THIS_MODULE,
147 	.name = "netiucv",
148 	.bus  = &iucv_bus,
149 	.pm = &netiucv_pm_ops,
150 };
151 
152 static int netiucv_callback_connreq(struct iucv_path *, u8 *, u8 *);
153 static void netiucv_callback_connack(struct iucv_path *, u8 *);
154 static void netiucv_callback_connrej(struct iucv_path *, u8 *);
155 static void netiucv_callback_connsusp(struct iucv_path *, u8 *);
156 static void netiucv_callback_connres(struct iucv_path *, u8 *);
157 static void netiucv_callback_rx(struct iucv_path *, struct iucv_message *);
158 static void netiucv_callback_txdone(struct iucv_path *, struct iucv_message *);
159 
160 static struct iucv_handler netiucv_handler = {
161 	.path_pending	  = netiucv_callback_connreq,
162 	.path_complete	  = netiucv_callback_connack,
163 	.path_severed	  = netiucv_callback_connrej,
164 	.path_quiesced	  = netiucv_callback_connsusp,
165 	.path_resumed	  = netiucv_callback_connres,
166 	.message_pending  = netiucv_callback_rx,
167 	.message_complete = netiucv_callback_txdone
168 };
169 
170 /**
171  * Per connection profiling data
172  */
173 struct connection_profile {
174 	unsigned long maxmulti;
175 	unsigned long maxcqueue;
176 	unsigned long doios_single;
177 	unsigned long doios_multi;
178 	unsigned long txlen;
179 	unsigned long tx_time;
180 	unsigned long send_stamp;
181 	unsigned long tx_pending;
182 	unsigned long tx_max_pending;
183 };
184 
185 /**
186  * Representation of one iucv connection
187  */
188 struct iucv_connection {
189 	struct list_head	  list;
190 	struct iucv_path	  *path;
191 	struct sk_buff            *rx_buff;
192 	struct sk_buff            *tx_buff;
193 	struct sk_buff_head       collect_queue;
194 	struct sk_buff_head	  commit_queue;
195 	spinlock_t                collect_lock;
196 	int                       collect_len;
197 	int                       max_buffsize;
198 	fsm_timer                 timer;
199 	fsm_instance              *fsm;
200 	struct net_device         *netdev;
201 	struct connection_profile prof;
202 	char                      userid[9];
203 	char			  userdata[17];
204 };
205 
206 /**
207  * Linked list of all connection structs.
208  */
209 static LIST_HEAD(iucv_connection_list);
210 static DEFINE_RWLOCK(iucv_connection_rwlock);
211 
212 /**
213  * Representation of event-data for the
214  * connection state machine.
215  */
216 struct iucv_event {
217 	struct iucv_connection *conn;
218 	void                   *data;
219 };
220 
221 /**
222  * Private part of the network device structure
223  */
224 struct netiucv_priv {
225 	struct net_device_stats stats;
226 	unsigned long           tbusy;
227 	fsm_instance            *fsm;
228         struct iucv_connection  *conn;
229 	struct device           *dev;
230 	int			 pm_state;
231 };
232 
233 /**
234  * Link level header for a packet.
235  */
236 struct ll_header {
237 	u16 next;
238 };
239 
240 #define NETIUCV_HDRLEN		 (sizeof(struct ll_header))
241 #define NETIUCV_BUFSIZE_MAX	 65537
242 #define NETIUCV_BUFSIZE_DEFAULT  NETIUCV_BUFSIZE_MAX
243 #define NETIUCV_MTU_MAX          (NETIUCV_BUFSIZE_MAX - NETIUCV_HDRLEN)
244 #define NETIUCV_MTU_DEFAULT      9216
245 #define NETIUCV_QUEUELEN_DEFAULT 50
246 #define NETIUCV_TIMEOUT_5SEC     5000
247 
248 /**
249  * Compatibility macros for busy handling
250  * of network devices.
251  */
252 static inline void netiucv_clear_busy(struct net_device *dev)
253 {
254 	struct netiucv_priv *priv = netdev_priv(dev);
255 	clear_bit(0, &priv->tbusy);
256 	netif_wake_queue(dev);
257 }
258 
259 static inline int netiucv_test_and_set_busy(struct net_device *dev)
260 {
261 	struct netiucv_priv *priv = netdev_priv(dev);
262 	netif_stop_queue(dev);
263 	return test_and_set_bit(0, &priv->tbusy);
264 }
265 
266 static u8 iucvMagic_ascii[16] = {
267 	0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
268 	0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20
269 };
270 
271 static u8 iucvMagic_ebcdic[16] = {
272 	0xF0, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,
273 	0xF0, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40
274 };
275 
276 /**
277  * Convert an iucv userId to its printable
278  * form (strip whitespace at end).
279  *
280  * @param An iucv userId
281  *
282  * @returns The printable string (static data!!)
283  */
284 static char *netiucv_printname(char *name, int len)
285 {
286 	static char tmp[17];
287 	char *p = tmp;
288 	memcpy(tmp, name, len);
289 	tmp[len] = '\0';
290 	while (*p && ((p - tmp) < len) && (!isspace(*p)))
291 		p++;
292 	*p = '\0';
293 	return tmp;
294 }
295 
296 static char *netiucv_printuser(struct iucv_connection *conn)
297 {
298 	static char tmp_uid[9];
299 	static char tmp_udat[17];
300 	static char buf[100];
301 
302 	if (memcmp(conn->userdata, iucvMagic_ebcdic, 16)) {
303 		tmp_uid[8] = '\0';
304 		tmp_udat[16] = '\0';
305 		memcpy(tmp_uid, conn->userid, 8);
306 		memcpy(tmp_uid, netiucv_printname(tmp_uid, 8), 8);
307 		memcpy(tmp_udat, conn->userdata, 16);
308 		EBCASC(tmp_udat, 16);
309 		memcpy(tmp_udat, netiucv_printname(tmp_udat, 16), 16);
310 		sprintf(buf, "%s.%s", tmp_uid, tmp_udat);
311 		return buf;
312 	} else
313 		return netiucv_printname(conn->userid, 8);
314 }
315 
316 /**
317  * States of the interface statemachine.
318  */
319 enum dev_states {
320 	DEV_STATE_STOPPED,
321 	DEV_STATE_STARTWAIT,
322 	DEV_STATE_STOPWAIT,
323 	DEV_STATE_RUNNING,
324 	/**
325 	 * MUST be always the last element!!
326 	 */
327 	NR_DEV_STATES
328 };
329 
330 static const char *dev_state_names[] = {
331 	"Stopped",
332 	"StartWait",
333 	"StopWait",
334 	"Running",
335 };
336 
337 /**
338  * Events of the interface statemachine.
339  */
340 enum dev_events {
341 	DEV_EVENT_START,
342 	DEV_EVENT_STOP,
343 	DEV_EVENT_CONUP,
344 	DEV_EVENT_CONDOWN,
345 	/**
346 	 * MUST be always the last element!!
347 	 */
348 	NR_DEV_EVENTS
349 };
350 
351 static const char *dev_event_names[] = {
352 	"Start",
353 	"Stop",
354 	"Connection up",
355 	"Connection down",
356 };
357 
358 /**
359  * Events of the connection statemachine
360  */
361 enum conn_events {
362 	/**
363 	 * Events, representing callbacks from
364 	 * lowlevel iucv layer)
365 	 */
366 	CONN_EVENT_CONN_REQ,
367 	CONN_EVENT_CONN_ACK,
368 	CONN_EVENT_CONN_REJ,
369 	CONN_EVENT_CONN_SUS,
370 	CONN_EVENT_CONN_RES,
371 	CONN_EVENT_RX,
372 	CONN_EVENT_TXDONE,
373 
374 	/**
375 	 * Events, representing errors return codes from
376 	 * calls to lowlevel iucv layer
377 	 */
378 
379 	/**
380 	 * Event, representing timer expiry.
381 	 */
382 	CONN_EVENT_TIMER,
383 
384 	/**
385 	 * Events, representing commands from upper levels.
386 	 */
387 	CONN_EVENT_START,
388 	CONN_EVENT_STOP,
389 
390 	/**
391 	 * MUST be always the last element!!
392 	 */
393 	NR_CONN_EVENTS,
394 };
395 
396 static const char *conn_event_names[] = {
397 	"Remote connection request",
398 	"Remote connection acknowledge",
399 	"Remote connection reject",
400 	"Connection suspended",
401 	"Connection resumed",
402 	"Data received",
403 	"Data sent",
404 
405 	"Timer",
406 
407 	"Start",
408 	"Stop",
409 };
410 
411 /**
412  * States of the connection statemachine.
413  */
414 enum conn_states {
415 	/**
416 	 * Connection not assigned to any device,
417 	 * initial state, invalid
418 	 */
419 	CONN_STATE_INVALID,
420 
421 	/**
422 	 * Userid assigned but not operating
423 	 */
424 	CONN_STATE_STOPPED,
425 
426 	/**
427 	 * Connection registered,
428 	 * no connection request sent yet,
429 	 * no connection request received
430 	 */
431 	CONN_STATE_STARTWAIT,
432 
433 	/**
434 	 * Connection registered and connection request sent,
435 	 * no acknowledge and no connection request received yet.
436 	 */
437 	CONN_STATE_SETUPWAIT,
438 
439 	/**
440 	 * Connection up and running idle
441 	 */
442 	CONN_STATE_IDLE,
443 
444 	/**
445 	 * Data sent, awaiting CONN_EVENT_TXDONE
446 	 */
447 	CONN_STATE_TX,
448 
449 	/**
450 	 * Error during registration.
451 	 */
452 	CONN_STATE_REGERR,
453 
454 	/**
455 	 * Error during registration.
456 	 */
457 	CONN_STATE_CONNERR,
458 
459 	/**
460 	 * MUST be always the last element!!
461 	 */
462 	NR_CONN_STATES,
463 };
464 
465 static const char *conn_state_names[] = {
466 	"Invalid",
467 	"Stopped",
468 	"StartWait",
469 	"SetupWait",
470 	"Idle",
471 	"TX",
472 	"Terminating",
473 	"Registration error",
474 	"Connect error",
475 };
476 
477 
478 /**
479  * Debug Facility Stuff
480  */
481 static debug_info_t *iucv_dbf_setup = NULL;
482 static debug_info_t *iucv_dbf_data = NULL;
483 static debug_info_t *iucv_dbf_trace = NULL;
484 
485 DEFINE_PER_CPU(char[256], iucv_dbf_txt_buf);
486 
487 static void iucv_unregister_dbf_views(void)
488 {
489 	debug_unregister(iucv_dbf_setup);
490 	debug_unregister(iucv_dbf_data);
491 	debug_unregister(iucv_dbf_trace);
492 }
493 static int iucv_register_dbf_views(void)
494 {
495 	iucv_dbf_setup = debug_register(IUCV_DBF_SETUP_NAME,
496 					IUCV_DBF_SETUP_PAGES,
497 					IUCV_DBF_SETUP_NR_AREAS,
498 					IUCV_DBF_SETUP_LEN);
499 	iucv_dbf_data = debug_register(IUCV_DBF_DATA_NAME,
500 				       IUCV_DBF_DATA_PAGES,
501 				       IUCV_DBF_DATA_NR_AREAS,
502 				       IUCV_DBF_DATA_LEN);
503 	iucv_dbf_trace = debug_register(IUCV_DBF_TRACE_NAME,
504 					IUCV_DBF_TRACE_PAGES,
505 					IUCV_DBF_TRACE_NR_AREAS,
506 					IUCV_DBF_TRACE_LEN);
507 
508 	if ((iucv_dbf_setup == NULL) || (iucv_dbf_data == NULL) ||
509 	    (iucv_dbf_trace == NULL)) {
510 		iucv_unregister_dbf_views();
511 		return -ENOMEM;
512 	}
513 	debug_register_view(iucv_dbf_setup, &debug_hex_ascii_view);
514 	debug_set_level(iucv_dbf_setup, IUCV_DBF_SETUP_LEVEL);
515 
516 	debug_register_view(iucv_dbf_data, &debug_hex_ascii_view);
517 	debug_set_level(iucv_dbf_data, IUCV_DBF_DATA_LEVEL);
518 
519 	debug_register_view(iucv_dbf_trace, &debug_hex_ascii_view);
520 	debug_set_level(iucv_dbf_trace, IUCV_DBF_TRACE_LEVEL);
521 
522 	return 0;
523 }
524 
525 /*
526  * Callback-wrappers, called from lowlevel iucv layer.
527  */
528 
529 static void netiucv_callback_rx(struct iucv_path *path,
530 				struct iucv_message *msg)
531 {
532 	struct iucv_connection *conn = path->private;
533 	struct iucv_event ev;
534 
535 	ev.conn = conn;
536 	ev.data = msg;
537 	fsm_event(conn->fsm, CONN_EVENT_RX, &ev);
538 }
539 
540 static void netiucv_callback_txdone(struct iucv_path *path,
541 				    struct iucv_message *msg)
542 {
543 	struct iucv_connection *conn = path->private;
544 	struct iucv_event ev;
545 
546 	ev.conn = conn;
547 	ev.data = msg;
548 	fsm_event(conn->fsm, CONN_EVENT_TXDONE, &ev);
549 }
550 
551 static void netiucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
552 {
553 	struct iucv_connection *conn = path->private;
554 
555 	fsm_event(conn->fsm, CONN_EVENT_CONN_ACK, conn);
556 }
557 
558 static int netiucv_callback_connreq(struct iucv_path *path, u8 *ipvmid,
559 				    u8 *ipuser)
560 {
561 	struct iucv_connection *conn = path->private;
562 	struct iucv_event ev;
563 	static char tmp_user[9];
564 	static char tmp_udat[17];
565 	int rc;
566 
567 	rc = -EINVAL;
568 	memcpy(tmp_user, netiucv_printname(ipvmid, 8), 8);
569 	memcpy(tmp_udat, ipuser, 16);
570 	EBCASC(tmp_udat, 16);
571 	read_lock_bh(&iucv_connection_rwlock);
572 	list_for_each_entry(conn, &iucv_connection_list, list) {
573 		if (strncmp(ipvmid, conn->userid, 8) ||
574 		    strncmp(ipuser, conn->userdata, 16))
575 			continue;
576 		/* Found a matching connection for this path. */
577 		conn->path = path;
578 		ev.conn = conn;
579 		ev.data = path;
580 		fsm_event(conn->fsm, CONN_EVENT_CONN_REQ, &ev);
581 		rc = 0;
582 	}
583 	IUCV_DBF_TEXT_(setup, 2, "Connection requested for %s.%s\n",
584 		       tmp_user, netiucv_printname(tmp_udat, 16));
585 	read_unlock_bh(&iucv_connection_rwlock);
586 	return rc;
587 }
588 
589 static void netiucv_callback_connrej(struct iucv_path *path, u8 *ipuser)
590 {
591 	struct iucv_connection *conn = path->private;
592 
593 	fsm_event(conn->fsm, CONN_EVENT_CONN_REJ, conn);
594 }
595 
596 static void netiucv_callback_connsusp(struct iucv_path *path, u8 *ipuser)
597 {
598 	struct iucv_connection *conn = path->private;
599 
600 	fsm_event(conn->fsm, CONN_EVENT_CONN_SUS, conn);
601 }
602 
603 static void netiucv_callback_connres(struct iucv_path *path, u8 *ipuser)
604 {
605 	struct iucv_connection *conn = path->private;
606 
607 	fsm_event(conn->fsm, CONN_EVENT_CONN_RES, conn);
608 }
609 
610 /**
611  * NOP action for statemachines
612  */
613 static void netiucv_action_nop(fsm_instance *fi, int event, void *arg)
614 {
615 }
616 
617 /*
618  * Actions of the connection statemachine
619  */
620 
621 /**
622  * netiucv_unpack_skb
623  * @conn: The connection where this skb has been received.
624  * @pskb: The received skb.
625  *
626  * Unpack a just received skb and hand it over to upper layers.
627  * Helper function for conn_action_rx.
628  */
629 static void netiucv_unpack_skb(struct iucv_connection *conn,
630 			       struct sk_buff *pskb)
631 {
632 	struct net_device     *dev = conn->netdev;
633 	struct netiucv_priv   *privptr = netdev_priv(dev);
634 	u16 offset = 0;
635 
636 	skb_put(pskb, NETIUCV_HDRLEN);
637 	pskb->dev = dev;
638 	pskb->ip_summed = CHECKSUM_NONE;
639 	pskb->protocol = ntohs(ETH_P_IP);
640 
641 	while (1) {
642 		struct sk_buff *skb;
643 		struct ll_header *header = (struct ll_header *) pskb->data;
644 
645 		if (!header->next)
646 			break;
647 
648 		skb_pull(pskb, NETIUCV_HDRLEN);
649 		header->next -= offset;
650 		offset += header->next;
651 		header->next -= NETIUCV_HDRLEN;
652 		if (skb_tailroom(pskb) < header->next) {
653 			IUCV_DBF_TEXT_(data, 2, "Illegal next field: %d > %d\n",
654 				header->next, skb_tailroom(pskb));
655 			return;
656 		}
657 		skb_put(pskb, header->next);
658 		skb_reset_mac_header(pskb);
659 		skb = dev_alloc_skb(pskb->len);
660 		if (!skb) {
661 			IUCV_DBF_TEXT(data, 2,
662 				"Out of memory in netiucv_unpack_skb\n");
663 			privptr->stats.rx_dropped++;
664 			return;
665 		}
666 		skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
667 					  pskb->len);
668 		skb_reset_mac_header(skb);
669 		skb->dev = pskb->dev;
670 		skb->protocol = pskb->protocol;
671 		pskb->ip_summed = CHECKSUM_UNNECESSARY;
672 		privptr->stats.rx_packets++;
673 		privptr->stats.rx_bytes += skb->len;
674 		/*
675 		 * Since receiving is always initiated from a tasklet (in iucv.c),
676 		 * we must use netif_rx_ni() instead of netif_rx()
677 		 */
678 		netif_rx_ni(skb);
679 		skb_pull(pskb, header->next);
680 		skb_put(pskb, NETIUCV_HDRLEN);
681 	}
682 }
683 
684 static void conn_action_rx(fsm_instance *fi, int event, void *arg)
685 {
686 	struct iucv_event *ev = arg;
687 	struct iucv_connection *conn = ev->conn;
688 	struct iucv_message *msg = ev->data;
689 	struct netiucv_priv *privptr = netdev_priv(conn->netdev);
690 	int rc;
691 
692 	IUCV_DBF_TEXT(trace, 4, __func__);
693 
694 	if (!conn->netdev) {
695 		iucv_message_reject(conn->path, msg);
696 		IUCV_DBF_TEXT(data, 2,
697 			      "Received data for unlinked connection\n");
698 		return;
699 	}
700 	if (msg->length > conn->max_buffsize) {
701 		iucv_message_reject(conn->path, msg);
702 		privptr->stats.rx_dropped++;
703 		IUCV_DBF_TEXT_(data, 2, "msglen %d > max_buffsize %d\n",
704 			       msg->length, conn->max_buffsize);
705 		return;
706 	}
707 	conn->rx_buff->data = conn->rx_buff->head;
708 	skb_reset_tail_pointer(conn->rx_buff);
709 	conn->rx_buff->len = 0;
710 	rc = iucv_message_receive(conn->path, msg, 0, conn->rx_buff->data,
711 				  msg->length, NULL);
712 	if (rc || msg->length < 5) {
713 		privptr->stats.rx_errors++;
714 		IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_receive\n", rc);
715 		return;
716 	}
717 	netiucv_unpack_skb(conn, conn->rx_buff);
718 }
719 
720 static void conn_action_txdone(fsm_instance *fi, int event, void *arg)
721 {
722 	struct iucv_event *ev = arg;
723 	struct iucv_connection *conn = ev->conn;
724 	struct iucv_message *msg = ev->data;
725 	struct iucv_message txmsg;
726 	struct netiucv_priv *privptr = NULL;
727 	u32 single_flag = msg->tag;
728 	u32 txbytes = 0;
729 	u32 txpackets = 0;
730 	u32 stat_maxcq = 0;
731 	struct sk_buff *skb;
732 	unsigned long saveflags;
733 	struct ll_header header;
734 	int rc;
735 
736 	IUCV_DBF_TEXT(trace, 4, __func__);
737 
738 	if (!conn || !conn->netdev) {
739 		IUCV_DBF_TEXT(data, 2,
740 			      "Send confirmation for unlinked connection\n");
741 		return;
742 	}
743 	privptr = netdev_priv(conn->netdev);
744 	conn->prof.tx_pending--;
745 	if (single_flag) {
746 		if ((skb = skb_dequeue(&conn->commit_queue))) {
747 			atomic_dec(&skb->users);
748 			if (privptr) {
749 				privptr->stats.tx_packets++;
750 				privptr->stats.tx_bytes +=
751 					(skb->len - NETIUCV_HDRLEN
752 						  - NETIUCV_HDRLEN);
753 			}
754 			dev_kfree_skb_any(skb);
755 		}
756 	}
757 	conn->tx_buff->data = conn->tx_buff->head;
758 	skb_reset_tail_pointer(conn->tx_buff);
759 	conn->tx_buff->len = 0;
760 	spin_lock_irqsave(&conn->collect_lock, saveflags);
761 	while ((skb = skb_dequeue(&conn->collect_queue))) {
762 		header.next = conn->tx_buff->len + skb->len + NETIUCV_HDRLEN;
763 		memcpy(skb_put(conn->tx_buff, NETIUCV_HDRLEN), &header,
764 		       NETIUCV_HDRLEN);
765 		skb_copy_from_linear_data(skb,
766 					  skb_put(conn->tx_buff, skb->len),
767 					  skb->len);
768 		txbytes += skb->len;
769 		txpackets++;
770 		stat_maxcq++;
771 		atomic_dec(&skb->users);
772 		dev_kfree_skb_any(skb);
773 	}
774 	if (conn->collect_len > conn->prof.maxmulti)
775 		conn->prof.maxmulti = conn->collect_len;
776 	conn->collect_len = 0;
777 	spin_unlock_irqrestore(&conn->collect_lock, saveflags);
778 	if (conn->tx_buff->len == 0) {
779 		fsm_newstate(fi, CONN_STATE_IDLE);
780 		return;
781 	}
782 
783 	header.next = 0;
784 	memcpy(skb_put(conn->tx_buff, NETIUCV_HDRLEN), &header, NETIUCV_HDRLEN);
785 	conn->prof.send_stamp = jiffies;
786 	txmsg.class = 0;
787 	txmsg.tag = 0;
788 	rc = iucv_message_send(conn->path, &txmsg, 0, 0,
789 			       conn->tx_buff->data, conn->tx_buff->len);
790 	conn->prof.doios_multi++;
791 	conn->prof.txlen += conn->tx_buff->len;
792 	conn->prof.tx_pending++;
793 	if (conn->prof.tx_pending > conn->prof.tx_max_pending)
794 		conn->prof.tx_max_pending = conn->prof.tx_pending;
795 	if (rc) {
796 		conn->prof.tx_pending--;
797 		fsm_newstate(fi, CONN_STATE_IDLE);
798 		if (privptr)
799 			privptr->stats.tx_errors += txpackets;
800 		IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_send\n", rc);
801 	} else {
802 		if (privptr) {
803 			privptr->stats.tx_packets += txpackets;
804 			privptr->stats.tx_bytes += txbytes;
805 		}
806 		if (stat_maxcq > conn->prof.maxcqueue)
807 			conn->prof.maxcqueue = stat_maxcq;
808 	}
809 }
810 
811 static void conn_action_connaccept(fsm_instance *fi, int event, void *arg)
812 {
813 	struct iucv_event *ev = arg;
814 	struct iucv_connection *conn = ev->conn;
815 	struct iucv_path *path = ev->data;
816 	struct net_device *netdev = conn->netdev;
817 	struct netiucv_priv *privptr = netdev_priv(netdev);
818 	int rc;
819 
820 	IUCV_DBF_TEXT(trace, 3, __func__);
821 
822 	conn->path = path;
823 	path->msglim = NETIUCV_QUEUELEN_DEFAULT;
824 	path->flags = 0;
825 	rc = iucv_path_accept(path, &netiucv_handler, conn->userdata , conn);
826 	if (rc) {
827 		IUCV_DBF_TEXT_(setup, 2, "rc %d from iucv_accept", rc);
828 		return;
829 	}
830 	fsm_newstate(fi, CONN_STATE_IDLE);
831 	netdev->tx_queue_len = conn->path->msglim;
832 	fsm_event(privptr->fsm, DEV_EVENT_CONUP, netdev);
833 }
834 
835 static void conn_action_connreject(fsm_instance *fi, int event, void *arg)
836 {
837 	struct iucv_event *ev = arg;
838 	struct iucv_path *path = ev->data;
839 
840 	IUCV_DBF_TEXT(trace, 3, __func__);
841 	iucv_path_sever(path, NULL);
842 }
843 
844 static void conn_action_connack(fsm_instance *fi, int event, void *arg)
845 {
846 	struct iucv_connection *conn = arg;
847 	struct net_device *netdev = conn->netdev;
848 	struct netiucv_priv *privptr = netdev_priv(netdev);
849 
850 	IUCV_DBF_TEXT(trace, 3, __func__);
851 	fsm_deltimer(&conn->timer);
852 	fsm_newstate(fi, CONN_STATE_IDLE);
853 	netdev->tx_queue_len = conn->path->msglim;
854 	fsm_event(privptr->fsm, DEV_EVENT_CONUP, netdev);
855 }
856 
857 static void conn_action_conntimsev(fsm_instance *fi, int event, void *arg)
858 {
859 	struct iucv_connection *conn = arg;
860 
861 	IUCV_DBF_TEXT(trace, 3, __func__);
862 	fsm_deltimer(&conn->timer);
863 	iucv_path_sever(conn->path, conn->userdata);
864 	fsm_newstate(fi, CONN_STATE_STARTWAIT);
865 }
866 
867 static void conn_action_connsever(fsm_instance *fi, int event, void *arg)
868 {
869 	struct iucv_connection *conn = arg;
870 	struct net_device *netdev = conn->netdev;
871 	struct netiucv_priv *privptr = netdev_priv(netdev);
872 
873 	IUCV_DBF_TEXT(trace, 3, __func__);
874 
875 	fsm_deltimer(&conn->timer);
876 	iucv_path_sever(conn->path, conn->userdata);
877 	dev_info(privptr->dev, "The peer z/VM guest %s has closed the "
878 			       "connection\n", netiucv_printuser(conn));
879 	IUCV_DBF_TEXT(data, 2,
880 		      "conn_action_connsever: Remote dropped connection\n");
881 	fsm_newstate(fi, CONN_STATE_STARTWAIT);
882 	fsm_event(privptr->fsm, DEV_EVENT_CONDOWN, netdev);
883 }
884 
885 static void conn_action_start(fsm_instance *fi, int event, void *arg)
886 {
887 	struct iucv_connection *conn = arg;
888 	struct net_device *netdev = conn->netdev;
889 	struct netiucv_priv *privptr = netdev_priv(netdev);
890 	int rc;
891 
892 	IUCV_DBF_TEXT(trace, 3, __func__);
893 
894 	fsm_newstate(fi, CONN_STATE_STARTWAIT);
895 
896 	/*
897 	 * We must set the state before calling iucv_connect because the
898 	 * callback handler could be called at any point after the connection
899 	 * request is sent
900 	 */
901 
902 	fsm_newstate(fi, CONN_STATE_SETUPWAIT);
903 	conn->path = iucv_path_alloc(NETIUCV_QUEUELEN_DEFAULT, 0, GFP_KERNEL);
904 	IUCV_DBF_TEXT_(setup, 2, "%s: connecting to %s ...\n",
905 		netdev->name, netiucv_printuser(conn));
906 
907 	rc = iucv_path_connect(conn->path, &netiucv_handler, conn->userid,
908 			       NULL, conn->userdata, conn);
909 	switch (rc) {
910 	case 0:
911 		netdev->tx_queue_len = conn->path->msglim;
912 		fsm_addtimer(&conn->timer, NETIUCV_TIMEOUT_5SEC,
913 			     CONN_EVENT_TIMER, conn);
914 		return;
915 	case 11:
916 		dev_warn(privptr->dev,
917 			"The IUCV device failed to connect to z/VM guest %s\n",
918 			netiucv_printname(conn->userid, 8));
919 		fsm_newstate(fi, CONN_STATE_STARTWAIT);
920 		break;
921 	case 12:
922 		dev_warn(privptr->dev,
923 			"The IUCV device failed to connect to the peer on z/VM"
924 			" guest %s\n", netiucv_printname(conn->userid, 8));
925 		fsm_newstate(fi, CONN_STATE_STARTWAIT);
926 		break;
927 	case 13:
928 		dev_err(privptr->dev,
929 			"Connecting the IUCV device would exceed the maximum"
930 			" number of IUCV connections\n");
931 		fsm_newstate(fi, CONN_STATE_CONNERR);
932 		break;
933 	case 14:
934 		dev_err(privptr->dev,
935 			"z/VM guest %s has too many IUCV connections"
936 			" to connect with the IUCV device\n",
937 			netiucv_printname(conn->userid, 8));
938 		fsm_newstate(fi, CONN_STATE_CONNERR);
939 		break;
940 	case 15:
941 		dev_err(privptr->dev,
942 			"The IUCV device cannot connect to a z/VM guest with no"
943 			" IUCV authorization\n");
944 		fsm_newstate(fi, CONN_STATE_CONNERR);
945 		break;
946 	default:
947 		dev_err(privptr->dev,
948 			"Connecting the IUCV device failed with error %d\n",
949 			rc);
950 		fsm_newstate(fi, CONN_STATE_CONNERR);
951 		break;
952 	}
953 	IUCV_DBF_TEXT_(setup, 5, "iucv_connect rc is %d\n", rc);
954 	kfree(conn->path);
955 	conn->path = NULL;
956 }
957 
958 static void netiucv_purge_skb_queue(struct sk_buff_head *q)
959 {
960 	struct sk_buff *skb;
961 
962 	while ((skb = skb_dequeue(q))) {
963 		atomic_dec(&skb->users);
964 		dev_kfree_skb_any(skb);
965 	}
966 }
967 
968 static void conn_action_stop(fsm_instance *fi, int event, void *arg)
969 {
970 	struct iucv_event *ev = arg;
971 	struct iucv_connection *conn = ev->conn;
972 	struct net_device *netdev = conn->netdev;
973 	struct netiucv_priv *privptr = netdev_priv(netdev);
974 
975 	IUCV_DBF_TEXT(trace, 3, __func__);
976 
977 	fsm_deltimer(&conn->timer);
978 	fsm_newstate(fi, CONN_STATE_STOPPED);
979 	netiucv_purge_skb_queue(&conn->collect_queue);
980 	if (conn->path) {
981 		IUCV_DBF_TEXT(trace, 5, "calling iucv_path_sever\n");
982 		iucv_path_sever(conn->path, conn->userdata);
983 		kfree(conn->path);
984 		conn->path = NULL;
985 	}
986 	netiucv_purge_skb_queue(&conn->commit_queue);
987 	fsm_event(privptr->fsm, DEV_EVENT_CONDOWN, netdev);
988 }
989 
990 static void conn_action_inval(fsm_instance *fi, int event, void *arg)
991 {
992 	struct iucv_connection *conn = arg;
993 	struct net_device *netdev = conn->netdev;
994 
995 	IUCV_DBF_TEXT_(data, 2, "%s('%s'): conn_action_inval called\n",
996 		netdev->name, conn->userid);
997 }
998 
999 static const fsm_node conn_fsm[] = {
1000 	{ CONN_STATE_INVALID,   CONN_EVENT_START,    conn_action_inval      },
1001 	{ CONN_STATE_STOPPED,   CONN_EVENT_START,    conn_action_start      },
1002 
1003 	{ CONN_STATE_STOPPED,   CONN_EVENT_STOP,     conn_action_stop       },
1004 	{ CONN_STATE_STARTWAIT, CONN_EVENT_STOP,     conn_action_stop       },
1005 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_STOP,     conn_action_stop       },
1006 	{ CONN_STATE_IDLE,      CONN_EVENT_STOP,     conn_action_stop       },
1007 	{ CONN_STATE_TX,        CONN_EVENT_STOP,     conn_action_stop       },
1008 	{ CONN_STATE_REGERR,    CONN_EVENT_STOP,     conn_action_stop       },
1009 	{ CONN_STATE_CONNERR,   CONN_EVENT_STOP,     conn_action_stop       },
1010 
1011 	{ CONN_STATE_STOPPED,   CONN_EVENT_CONN_REQ, conn_action_connreject },
1012         { CONN_STATE_STARTWAIT, CONN_EVENT_CONN_REQ, conn_action_connaccept },
1013 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_REQ, conn_action_connaccept },
1014 	{ CONN_STATE_IDLE,      CONN_EVENT_CONN_REQ, conn_action_connreject },
1015 	{ CONN_STATE_TX,        CONN_EVENT_CONN_REQ, conn_action_connreject },
1016 
1017 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_ACK, conn_action_connack    },
1018 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_TIMER,    conn_action_conntimsev },
1019 
1020 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_REJ, conn_action_connsever  },
1021 	{ CONN_STATE_IDLE,      CONN_EVENT_CONN_REJ, conn_action_connsever  },
1022 	{ CONN_STATE_TX,        CONN_EVENT_CONN_REJ, conn_action_connsever  },
1023 
1024 	{ CONN_STATE_IDLE,      CONN_EVENT_RX,       conn_action_rx         },
1025 	{ CONN_STATE_TX,        CONN_EVENT_RX,       conn_action_rx         },
1026 
1027 	{ CONN_STATE_TX,        CONN_EVENT_TXDONE,   conn_action_txdone     },
1028 	{ CONN_STATE_IDLE,      CONN_EVENT_TXDONE,   conn_action_txdone     },
1029 };
1030 
1031 static const int CONN_FSM_LEN = sizeof(conn_fsm) / sizeof(fsm_node);
1032 
1033 
1034 /*
1035  * Actions for interface - statemachine.
1036  */
1037 
1038 /**
1039  * dev_action_start
1040  * @fi: An instance of an interface statemachine.
1041  * @event: The event, just happened.
1042  * @arg: Generic pointer, casted from struct net_device * upon call.
1043  *
1044  * Startup connection by sending CONN_EVENT_START to it.
1045  */
1046 static void dev_action_start(fsm_instance *fi, int event, void *arg)
1047 {
1048 	struct net_device   *dev = arg;
1049 	struct netiucv_priv *privptr = netdev_priv(dev);
1050 
1051 	IUCV_DBF_TEXT(trace, 3, __func__);
1052 
1053 	fsm_newstate(fi, DEV_STATE_STARTWAIT);
1054 	fsm_event(privptr->conn->fsm, CONN_EVENT_START, privptr->conn);
1055 }
1056 
1057 /**
1058  * Shutdown connection by sending CONN_EVENT_STOP to it.
1059  *
1060  * @param fi    An instance of an interface statemachine.
1061  * @param event The event, just happened.
1062  * @param arg   Generic pointer, casted from struct net_device * upon call.
1063  */
1064 static void
1065 dev_action_stop(fsm_instance *fi, int event, void *arg)
1066 {
1067 	struct net_device   *dev = arg;
1068 	struct netiucv_priv *privptr = netdev_priv(dev);
1069 	struct iucv_event   ev;
1070 
1071 	IUCV_DBF_TEXT(trace, 3, __func__);
1072 
1073 	ev.conn = privptr->conn;
1074 
1075 	fsm_newstate(fi, DEV_STATE_STOPWAIT);
1076 	fsm_event(privptr->conn->fsm, CONN_EVENT_STOP, &ev);
1077 }
1078 
1079 /**
1080  * Called from connection statemachine
1081  * when a connection is up and running.
1082  *
1083  * @param fi    An instance of an interface statemachine.
1084  * @param event The event, just happened.
1085  * @param arg   Generic pointer, casted from struct net_device * upon call.
1086  */
1087 static void
1088 dev_action_connup(fsm_instance *fi, int event, void *arg)
1089 {
1090 	struct net_device   *dev = arg;
1091 	struct netiucv_priv *privptr = netdev_priv(dev);
1092 
1093 	IUCV_DBF_TEXT(trace, 3, __func__);
1094 
1095 	switch (fsm_getstate(fi)) {
1096 		case DEV_STATE_STARTWAIT:
1097 			fsm_newstate(fi, DEV_STATE_RUNNING);
1098 			dev_info(privptr->dev,
1099 				"The IUCV device has been connected"
1100 				" successfully to %s\n",
1101 				netiucv_printuser(privptr->conn));
1102 			IUCV_DBF_TEXT(setup, 3,
1103 				"connection is up and running\n");
1104 			break;
1105 		case DEV_STATE_STOPWAIT:
1106 			IUCV_DBF_TEXT(data, 2,
1107 				"dev_action_connup: in DEV_STATE_STOPWAIT\n");
1108 			break;
1109 	}
1110 }
1111 
1112 /**
1113  * Called from connection statemachine
1114  * when a connection has been shutdown.
1115  *
1116  * @param fi    An instance of an interface statemachine.
1117  * @param event The event, just happened.
1118  * @param arg   Generic pointer, casted from struct net_device * upon call.
1119  */
1120 static void
1121 dev_action_conndown(fsm_instance *fi, int event, void *arg)
1122 {
1123 	IUCV_DBF_TEXT(trace, 3, __func__);
1124 
1125 	switch (fsm_getstate(fi)) {
1126 		case DEV_STATE_RUNNING:
1127 			fsm_newstate(fi, DEV_STATE_STARTWAIT);
1128 			break;
1129 		case DEV_STATE_STOPWAIT:
1130 			fsm_newstate(fi, DEV_STATE_STOPPED);
1131 			IUCV_DBF_TEXT(setup, 3, "connection is down\n");
1132 			break;
1133 	}
1134 }
1135 
1136 static const fsm_node dev_fsm[] = {
1137 	{ DEV_STATE_STOPPED,    DEV_EVENT_START,   dev_action_start    },
1138 
1139 	{ DEV_STATE_STOPWAIT,   DEV_EVENT_START,   dev_action_start    },
1140 	{ DEV_STATE_STOPWAIT,   DEV_EVENT_CONDOWN, dev_action_conndown },
1141 
1142 	{ DEV_STATE_STARTWAIT,  DEV_EVENT_STOP,    dev_action_stop     },
1143 	{ DEV_STATE_STARTWAIT,  DEV_EVENT_CONUP,   dev_action_connup   },
1144 
1145 	{ DEV_STATE_RUNNING,    DEV_EVENT_STOP,    dev_action_stop     },
1146 	{ DEV_STATE_RUNNING,    DEV_EVENT_CONDOWN, dev_action_conndown },
1147 	{ DEV_STATE_RUNNING,    DEV_EVENT_CONUP,   netiucv_action_nop  },
1148 };
1149 
1150 static const int DEV_FSM_LEN = sizeof(dev_fsm) / sizeof(fsm_node);
1151 
1152 /**
1153  * Transmit a packet.
1154  * This is a helper function for netiucv_tx().
1155  *
1156  * @param conn Connection to be used for sending.
1157  * @param skb Pointer to struct sk_buff of packet to send.
1158  *            The linklevel header has already been set up
1159  *            by netiucv_tx().
1160  *
1161  * @return 0 on success, -ERRNO on failure. (Never fails.)
1162  */
1163 static int netiucv_transmit_skb(struct iucv_connection *conn,
1164 				struct sk_buff *skb)
1165 {
1166 	struct iucv_message msg;
1167 	unsigned long saveflags;
1168 	struct ll_header header;
1169 	int rc;
1170 
1171 	if (fsm_getstate(conn->fsm) != CONN_STATE_IDLE) {
1172 		int l = skb->len + NETIUCV_HDRLEN;
1173 
1174 		spin_lock_irqsave(&conn->collect_lock, saveflags);
1175 		if (conn->collect_len + l >
1176 		    (conn->max_buffsize - NETIUCV_HDRLEN)) {
1177 			rc = -EBUSY;
1178 			IUCV_DBF_TEXT(data, 2,
1179 				      "EBUSY from netiucv_transmit_skb\n");
1180 		} else {
1181 			atomic_inc(&skb->users);
1182 			skb_queue_tail(&conn->collect_queue, skb);
1183 			conn->collect_len += l;
1184 			rc = 0;
1185 		}
1186 		spin_unlock_irqrestore(&conn->collect_lock, saveflags);
1187 	} else {
1188 		struct sk_buff *nskb = skb;
1189 		/**
1190 		 * Copy the skb to a new allocated skb in lowmem only if the
1191 		 * data is located above 2G in memory or tailroom is < 2.
1192 		 */
1193 		unsigned long hi = ((unsigned long)(skb_tail_pointer(skb) +
1194 				    NETIUCV_HDRLEN)) >> 31;
1195 		int copied = 0;
1196 		if (hi || (skb_tailroom(skb) < 2)) {
1197 			nskb = alloc_skb(skb->len + NETIUCV_HDRLEN +
1198 					 NETIUCV_HDRLEN, GFP_ATOMIC | GFP_DMA);
1199 			if (!nskb) {
1200 				IUCV_DBF_TEXT(data, 2, "alloc_skb failed\n");
1201 				rc = -ENOMEM;
1202 				return rc;
1203 			} else {
1204 				skb_reserve(nskb, NETIUCV_HDRLEN);
1205 				memcpy(skb_put(nskb, skb->len),
1206 				       skb->data, skb->len);
1207 			}
1208 			copied = 1;
1209 		}
1210 		/**
1211 		 * skb now is below 2G and has enough room. Add headers.
1212 		 */
1213 		header.next = nskb->len + NETIUCV_HDRLEN;
1214 		memcpy(skb_push(nskb, NETIUCV_HDRLEN), &header, NETIUCV_HDRLEN);
1215 		header.next = 0;
1216 		memcpy(skb_put(nskb, NETIUCV_HDRLEN), &header,  NETIUCV_HDRLEN);
1217 
1218 		fsm_newstate(conn->fsm, CONN_STATE_TX);
1219 		conn->prof.send_stamp = jiffies;
1220 
1221 		msg.tag = 1;
1222 		msg.class = 0;
1223 		rc = iucv_message_send(conn->path, &msg, 0, 0,
1224 				       nskb->data, nskb->len);
1225 		conn->prof.doios_single++;
1226 		conn->prof.txlen += skb->len;
1227 		conn->prof.tx_pending++;
1228 		if (conn->prof.tx_pending > conn->prof.tx_max_pending)
1229 			conn->prof.tx_max_pending = conn->prof.tx_pending;
1230 		if (rc) {
1231 			struct netiucv_priv *privptr;
1232 			fsm_newstate(conn->fsm, CONN_STATE_IDLE);
1233 			conn->prof.tx_pending--;
1234 			privptr = netdev_priv(conn->netdev);
1235 			if (privptr)
1236 				privptr->stats.tx_errors++;
1237 			if (copied)
1238 				dev_kfree_skb(nskb);
1239 			else {
1240 				/**
1241 				 * Remove our headers. They get added
1242 				 * again on retransmit.
1243 				 */
1244 				skb_pull(skb, NETIUCV_HDRLEN);
1245 				skb_trim(skb, skb->len - NETIUCV_HDRLEN);
1246 			}
1247 			IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_send\n", rc);
1248 		} else {
1249 			if (copied)
1250 				dev_kfree_skb(skb);
1251 			atomic_inc(&nskb->users);
1252 			skb_queue_tail(&conn->commit_queue, nskb);
1253 		}
1254 	}
1255 
1256 	return rc;
1257 }
1258 
1259 /*
1260  * Interface API for upper network layers
1261  */
1262 
1263 /**
1264  * Open an interface.
1265  * Called from generic network layer when ifconfig up is run.
1266  *
1267  * @param dev Pointer to interface struct.
1268  *
1269  * @return 0 on success, -ERRNO on failure. (Never fails.)
1270  */
1271 static int netiucv_open(struct net_device *dev)
1272 {
1273 	struct netiucv_priv *priv = netdev_priv(dev);
1274 
1275 	fsm_event(priv->fsm, DEV_EVENT_START, dev);
1276 	return 0;
1277 }
1278 
1279 /**
1280  * Close an interface.
1281  * Called from generic network layer when ifconfig down is run.
1282  *
1283  * @param dev Pointer to interface struct.
1284  *
1285  * @return 0 on success, -ERRNO on failure. (Never fails.)
1286  */
1287 static int netiucv_close(struct net_device *dev)
1288 {
1289 	struct netiucv_priv *priv = netdev_priv(dev);
1290 
1291 	fsm_event(priv->fsm, DEV_EVENT_STOP, dev);
1292 	return 0;
1293 }
1294 
1295 static int netiucv_pm_prepare(struct device *dev)
1296 {
1297 	IUCV_DBF_TEXT(trace, 3, __func__);
1298 	return 0;
1299 }
1300 
1301 static void netiucv_pm_complete(struct device *dev)
1302 {
1303 	IUCV_DBF_TEXT(trace, 3, __func__);
1304 	return;
1305 }
1306 
1307 /**
1308  * netiucv_pm_freeze() - Freeze PM callback
1309  * @dev:	netiucv device
1310  *
1311  * close open netiucv interfaces
1312  */
1313 static int netiucv_pm_freeze(struct device *dev)
1314 {
1315 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1316 	struct net_device *ndev = NULL;
1317 	int rc = 0;
1318 
1319 	IUCV_DBF_TEXT(trace, 3, __func__);
1320 	if (priv && priv->conn)
1321 		ndev = priv->conn->netdev;
1322 	if (!ndev)
1323 		goto out;
1324 	netif_device_detach(ndev);
1325 	priv->pm_state = fsm_getstate(priv->fsm);
1326 	rc = netiucv_close(ndev);
1327 out:
1328 	return rc;
1329 }
1330 
1331 /**
1332  * netiucv_pm_restore_thaw() - Thaw and restore PM callback
1333  * @dev:	netiucv device
1334  *
1335  * re-open netiucv interfaces closed during freeze
1336  */
1337 static int netiucv_pm_restore_thaw(struct device *dev)
1338 {
1339 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1340 	struct net_device *ndev = NULL;
1341 	int rc = 0;
1342 
1343 	IUCV_DBF_TEXT(trace, 3, __func__);
1344 	if (priv && priv->conn)
1345 		ndev = priv->conn->netdev;
1346 	if (!ndev)
1347 		goto out;
1348 	switch (priv->pm_state) {
1349 	case DEV_STATE_RUNNING:
1350 	case DEV_STATE_STARTWAIT:
1351 		rc = netiucv_open(ndev);
1352 		break;
1353 	default:
1354 		break;
1355 	}
1356 	netif_device_attach(ndev);
1357 out:
1358 	return rc;
1359 }
1360 
1361 /**
1362  * Start transmission of a packet.
1363  * Called from generic network device layer.
1364  *
1365  * @param skb Pointer to buffer containing the packet.
1366  * @param dev Pointer to interface struct.
1367  *
1368  * @return 0 if packet consumed, !0 if packet rejected.
1369  *         Note: If we return !0, then the packet is free'd by
1370  *               the generic network layer.
1371  */
1372 static int netiucv_tx(struct sk_buff *skb, struct net_device *dev)
1373 {
1374 	struct netiucv_priv *privptr = netdev_priv(dev);
1375 	int rc;
1376 
1377 	IUCV_DBF_TEXT(trace, 4, __func__);
1378 	/**
1379 	 * Some sanity checks ...
1380 	 */
1381 	if (skb == NULL) {
1382 		IUCV_DBF_TEXT(data, 2, "netiucv_tx: skb is NULL\n");
1383 		privptr->stats.tx_dropped++;
1384 		return NETDEV_TX_OK;
1385 	}
1386 	if (skb_headroom(skb) < NETIUCV_HDRLEN) {
1387 		IUCV_DBF_TEXT(data, 2,
1388 			"netiucv_tx: skb_headroom < NETIUCV_HDRLEN\n");
1389 		dev_kfree_skb(skb);
1390 		privptr->stats.tx_dropped++;
1391 		return NETDEV_TX_OK;
1392 	}
1393 
1394 	/**
1395 	 * If connection is not running, try to restart it
1396 	 * and throw away packet.
1397 	 */
1398 	if (fsm_getstate(privptr->fsm) != DEV_STATE_RUNNING) {
1399 		dev_kfree_skb(skb);
1400 		privptr->stats.tx_dropped++;
1401 		privptr->stats.tx_errors++;
1402 		privptr->stats.tx_carrier_errors++;
1403 		return NETDEV_TX_OK;
1404 	}
1405 
1406 	if (netiucv_test_and_set_busy(dev)) {
1407 		IUCV_DBF_TEXT(data, 2, "EBUSY from netiucv_tx\n");
1408 		return NETDEV_TX_BUSY;
1409 	}
1410 	dev->trans_start = jiffies;
1411 	rc = netiucv_transmit_skb(privptr->conn, skb);
1412 	netiucv_clear_busy(dev);
1413 	return rc ? NETDEV_TX_BUSY : NETDEV_TX_OK;
1414 }
1415 
1416 /**
1417  * netiucv_stats
1418  * @dev: Pointer to interface struct.
1419  *
1420  * Returns interface statistics of a device.
1421  *
1422  * Returns pointer to stats struct of this interface.
1423  */
1424 static struct net_device_stats *netiucv_stats (struct net_device * dev)
1425 {
1426 	struct netiucv_priv *priv = netdev_priv(dev);
1427 
1428 	IUCV_DBF_TEXT(trace, 5, __func__);
1429 	return &priv->stats;
1430 }
1431 
1432 /**
1433  * netiucv_change_mtu
1434  * @dev: Pointer to interface struct.
1435  * @new_mtu: The new MTU to use for this interface.
1436  *
1437  * Sets MTU of an interface.
1438  *
1439  * Returns 0 on success, -EINVAL if MTU is out of valid range.
1440  *         (valid range is 576 .. NETIUCV_MTU_MAX).
1441  */
1442 static int netiucv_change_mtu(struct net_device * dev, int new_mtu)
1443 {
1444 	IUCV_DBF_TEXT(trace, 3, __func__);
1445 	if (new_mtu < 576 || new_mtu > NETIUCV_MTU_MAX) {
1446 		IUCV_DBF_TEXT(setup, 2, "given MTU out of valid range\n");
1447 		return -EINVAL;
1448 	}
1449 	dev->mtu = new_mtu;
1450 	return 0;
1451 }
1452 
1453 /*
1454  * attributes in sysfs
1455  */
1456 
1457 static ssize_t user_show(struct device *dev, struct device_attribute *attr,
1458 			 char *buf)
1459 {
1460 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1461 
1462 	IUCV_DBF_TEXT(trace, 5, __func__);
1463 	return sprintf(buf, "%s\n", netiucv_printuser(priv->conn));
1464 }
1465 
1466 static int netiucv_check_user(const char *buf, size_t count, char *username,
1467 			      char *userdata)
1468 {
1469 	const char *p;
1470 	int i;
1471 
1472 	p = strchr(buf, '.');
1473 	if ((p && ((count > 26) ||
1474 		   ((p - buf) > 8) ||
1475 		   (buf + count - p > 18))) ||
1476 	    (!p && (count > 9))) {
1477 		IUCV_DBF_TEXT(setup, 2, "conn_write: too long\n");
1478 		return -EINVAL;
1479 	}
1480 
1481 	for (i = 0, p = buf; i < 8 && *p && *p != '.'; i++, p++) {
1482 		if (isalnum(*p) || *p == '$') {
1483 			username[i] = toupper(*p);
1484 			continue;
1485 		}
1486 		if (*p == '\n')
1487 			/* trailing lf, grr */
1488 			break;
1489 		IUCV_DBF_TEXT_(setup, 2,
1490 			       "conn_write: invalid character %02x\n", *p);
1491 		return -EINVAL;
1492 	}
1493 	while (i < 8)
1494 		username[i++] = ' ';
1495 	username[8] = '\0';
1496 
1497 	if (*p == '.') {
1498 		p++;
1499 		for (i = 0; i < 16 && *p; i++, p++) {
1500 			if (*p == '\n')
1501 				break;
1502 			userdata[i] = toupper(*p);
1503 		}
1504 		while (i > 0 && i < 16)
1505 			userdata[i++] = ' ';
1506 	} else
1507 		memcpy(userdata, iucvMagic_ascii, 16);
1508 	userdata[16] = '\0';
1509 	ASCEBC(userdata, 16);
1510 
1511 	return 0;
1512 }
1513 
1514 static ssize_t user_write(struct device *dev, struct device_attribute *attr,
1515 			  const char *buf, size_t count)
1516 {
1517 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1518 	struct net_device *ndev = priv->conn->netdev;
1519 	char	username[9];
1520 	char	userdata[17];
1521 	int	rc;
1522 	struct iucv_connection *cp;
1523 
1524 	IUCV_DBF_TEXT(trace, 3, __func__);
1525 	rc = netiucv_check_user(buf, count, username, userdata);
1526 	if (rc)
1527 		return rc;
1528 
1529 	if (memcmp(username, priv->conn->userid, 9) &&
1530 	    (ndev->flags & (IFF_UP | IFF_RUNNING))) {
1531 		/* username changed while the interface is active. */
1532 		IUCV_DBF_TEXT(setup, 2, "user_write: device active\n");
1533 		return -EPERM;
1534 	}
1535 	read_lock_bh(&iucv_connection_rwlock);
1536 	list_for_each_entry(cp, &iucv_connection_list, list) {
1537 		if (!strncmp(username, cp->userid, 9) &&
1538 		   !strncmp(userdata, cp->userdata, 17) && cp->netdev != ndev) {
1539 			read_unlock_bh(&iucv_connection_rwlock);
1540 			IUCV_DBF_TEXT_(setup, 2, "user_write: Connection to %s "
1541 				"already exists\n", netiucv_printuser(cp));
1542 			return -EEXIST;
1543 		}
1544 	}
1545 	read_unlock_bh(&iucv_connection_rwlock);
1546 	memcpy(priv->conn->userid, username, 9);
1547 	memcpy(priv->conn->userdata, userdata, 17);
1548 	return count;
1549 }
1550 
1551 static DEVICE_ATTR(user, 0644, user_show, user_write);
1552 
1553 static ssize_t buffer_show (struct device *dev, struct device_attribute *attr,
1554 			    char *buf)
1555 {
1556 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1557 
1558 	IUCV_DBF_TEXT(trace, 5, __func__);
1559 	return sprintf(buf, "%d\n", priv->conn->max_buffsize);
1560 }
1561 
1562 static ssize_t buffer_write (struct device *dev, struct device_attribute *attr,
1563 			     const char *buf, size_t count)
1564 {
1565 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1566 	struct net_device *ndev = priv->conn->netdev;
1567 	char         *e;
1568 	int          bs1;
1569 
1570 	IUCV_DBF_TEXT(trace, 3, __func__);
1571 	if (count >= 39)
1572 		return -EINVAL;
1573 
1574 	bs1 = simple_strtoul(buf, &e, 0);
1575 
1576 	if (e && (!isspace(*e))) {
1577 		IUCV_DBF_TEXT_(setup, 2, "buffer_write: invalid char %02x\n",
1578 			*e);
1579 		return -EINVAL;
1580 	}
1581 	if (bs1 > NETIUCV_BUFSIZE_MAX) {
1582 		IUCV_DBF_TEXT_(setup, 2,
1583 			"buffer_write: buffer size %d too large\n",
1584 			bs1);
1585 		return -EINVAL;
1586 	}
1587 	if ((ndev->flags & IFF_RUNNING) &&
1588 	    (bs1 < (ndev->mtu + NETIUCV_HDRLEN + 2))) {
1589 		IUCV_DBF_TEXT_(setup, 2,
1590 			"buffer_write: buffer size %d too small\n",
1591 			bs1);
1592 		return -EINVAL;
1593 	}
1594 	if (bs1 < (576 + NETIUCV_HDRLEN + NETIUCV_HDRLEN)) {
1595 		IUCV_DBF_TEXT_(setup, 2,
1596 			"buffer_write: buffer size %d too small\n",
1597 			bs1);
1598 		return -EINVAL;
1599 	}
1600 
1601 	priv->conn->max_buffsize = bs1;
1602 	if (!(ndev->flags & IFF_RUNNING))
1603 		ndev->mtu = bs1 - NETIUCV_HDRLEN - NETIUCV_HDRLEN;
1604 
1605 	return count;
1606 
1607 }
1608 
1609 static DEVICE_ATTR(buffer, 0644, buffer_show, buffer_write);
1610 
1611 static ssize_t dev_fsm_show (struct device *dev, struct device_attribute *attr,
1612 			     char *buf)
1613 {
1614 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1615 
1616 	IUCV_DBF_TEXT(trace, 5, __func__);
1617 	return sprintf(buf, "%s\n", fsm_getstate_str(priv->fsm));
1618 }
1619 
1620 static DEVICE_ATTR(device_fsm_state, 0444, dev_fsm_show, NULL);
1621 
1622 static ssize_t conn_fsm_show (struct device *dev,
1623 			      struct device_attribute *attr, char *buf)
1624 {
1625 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1626 
1627 	IUCV_DBF_TEXT(trace, 5, __func__);
1628 	return sprintf(buf, "%s\n", fsm_getstate_str(priv->conn->fsm));
1629 }
1630 
1631 static DEVICE_ATTR(connection_fsm_state, 0444, conn_fsm_show, NULL);
1632 
1633 static ssize_t maxmulti_show (struct device *dev,
1634 			      struct device_attribute *attr, char *buf)
1635 {
1636 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1637 
1638 	IUCV_DBF_TEXT(trace, 5, __func__);
1639 	return sprintf(buf, "%ld\n", priv->conn->prof.maxmulti);
1640 }
1641 
1642 static ssize_t maxmulti_write (struct device *dev,
1643 			       struct device_attribute *attr,
1644 			       const char *buf, size_t count)
1645 {
1646 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1647 
1648 	IUCV_DBF_TEXT(trace, 4, __func__);
1649 	priv->conn->prof.maxmulti = 0;
1650 	return count;
1651 }
1652 
1653 static DEVICE_ATTR(max_tx_buffer_used, 0644, maxmulti_show, maxmulti_write);
1654 
1655 static ssize_t maxcq_show (struct device *dev, struct device_attribute *attr,
1656 			   char *buf)
1657 {
1658 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1659 
1660 	IUCV_DBF_TEXT(trace, 5, __func__);
1661 	return sprintf(buf, "%ld\n", priv->conn->prof.maxcqueue);
1662 }
1663 
1664 static ssize_t maxcq_write (struct device *dev, struct device_attribute *attr,
1665 			    const char *buf, size_t count)
1666 {
1667 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1668 
1669 	IUCV_DBF_TEXT(trace, 4, __func__);
1670 	priv->conn->prof.maxcqueue = 0;
1671 	return count;
1672 }
1673 
1674 static DEVICE_ATTR(max_chained_skbs, 0644, maxcq_show, maxcq_write);
1675 
1676 static ssize_t sdoio_show (struct device *dev, struct device_attribute *attr,
1677 			   char *buf)
1678 {
1679 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1680 
1681 	IUCV_DBF_TEXT(trace, 5, __func__);
1682 	return sprintf(buf, "%ld\n", priv->conn->prof.doios_single);
1683 }
1684 
1685 static ssize_t sdoio_write (struct device *dev, struct device_attribute *attr,
1686 			    const char *buf, size_t count)
1687 {
1688 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1689 
1690 	IUCV_DBF_TEXT(trace, 4, __func__);
1691 	priv->conn->prof.doios_single = 0;
1692 	return count;
1693 }
1694 
1695 static DEVICE_ATTR(tx_single_write_ops, 0644, sdoio_show, sdoio_write);
1696 
1697 static ssize_t mdoio_show (struct device *dev, struct device_attribute *attr,
1698 			   char *buf)
1699 {
1700 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1701 
1702 	IUCV_DBF_TEXT(trace, 5, __func__);
1703 	return sprintf(buf, "%ld\n", priv->conn->prof.doios_multi);
1704 }
1705 
1706 static ssize_t mdoio_write (struct device *dev, struct device_attribute *attr,
1707 			    const char *buf, size_t count)
1708 {
1709 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1710 
1711 	IUCV_DBF_TEXT(trace, 5, __func__);
1712 	priv->conn->prof.doios_multi = 0;
1713 	return count;
1714 }
1715 
1716 static DEVICE_ATTR(tx_multi_write_ops, 0644, mdoio_show, mdoio_write);
1717 
1718 static ssize_t txlen_show (struct device *dev, struct device_attribute *attr,
1719 			   char *buf)
1720 {
1721 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1722 
1723 	IUCV_DBF_TEXT(trace, 5, __func__);
1724 	return sprintf(buf, "%ld\n", priv->conn->prof.txlen);
1725 }
1726 
1727 static ssize_t txlen_write (struct device *dev, struct device_attribute *attr,
1728 			    const char *buf, size_t count)
1729 {
1730 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1731 
1732 	IUCV_DBF_TEXT(trace, 4, __func__);
1733 	priv->conn->prof.txlen = 0;
1734 	return count;
1735 }
1736 
1737 static DEVICE_ATTR(netto_bytes, 0644, txlen_show, txlen_write);
1738 
1739 static ssize_t txtime_show (struct device *dev, struct device_attribute *attr,
1740 			    char *buf)
1741 {
1742 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1743 
1744 	IUCV_DBF_TEXT(trace, 5, __func__);
1745 	return sprintf(buf, "%ld\n", priv->conn->prof.tx_time);
1746 }
1747 
1748 static ssize_t txtime_write (struct device *dev, struct device_attribute *attr,
1749 			     const char *buf, size_t count)
1750 {
1751 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1752 
1753 	IUCV_DBF_TEXT(trace, 4, __func__);
1754 	priv->conn->prof.tx_time = 0;
1755 	return count;
1756 }
1757 
1758 static DEVICE_ATTR(max_tx_io_time, 0644, txtime_show, txtime_write);
1759 
1760 static ssize_t txpend_show (struct device *dev, struct device_attribute *attr,
1761 			    char *buf)
1762 {
1763 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1764 
1765 	IUCV_DBF_TEXT(trace, 5, __func__);
1766 	return sprintf(buf, "%ld\n", priv->conn->prof.tx_pending);
1767 }
1768 
1769 static ssize_t txpend_write (struct device *dev, struct device_attribute *attr,
1770 			     const char *buf, size_t count)
1771 {
1772 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1773 
1774 	IUCV_DBF_TEXT(trace, 4, __func__);
1775 	priv->conn->prof.tx_pending = 0;
1776 	return count;
1777 }
1778 
1779 static DEVICE_ATTR(tx_pending, 0644, txpend_show, txpend_write);
1780 
1781 static ssize_t txmpnd_show (struct device *dev, struct device_attribute *attr,
1782 			    char *buf)
1783 {
1784 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1785 
1786 	IUCV_DBF_TEXT(trace, 5, __func__);
1787 	return sprintf(buf, "%ld\n", priv->conn->prof.tx_max_pending);
1788 }
1789 
1790 static ssize_t txmpnd_write (struct device *dev, struct device_attribute *attr,
1791 			     const char *buf, size_t count)
1792 {
1793 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1794 
1795 	IUCV_DBF_TEXT(trace, 4, __func__);
1796 	priv->conn->prof.tx_max_pending = 0;
1797 	return count;
1798 }
1799 
1800 static DEVICE_ATTR(tx_max_pending, 0644, txmpnd_show, txmpnd_write);
1801 
1802 static struct attribute *netiucv_attrs[] = {
1803 	&dev_attr_buffer.attr,
1804 	&dev_attr_user.attr,
1805 	NULL,
1806 };
1807 
1808 static struct attribute_group netiucv_attr_group = {
1809 	.attrs = netiucv_attrs,
1810 };
1811 
1812 static struct attribute *netiucv_stat_attrs[] = {
1813 	&dev_attr_device_fsm_state.attr,
1814 	&dev_attr_connection_fsm_state.attr,
1815 	&dev_attr_max_tx_buffer_used.attr,
1816 	&dev_attr_max_chained_skbs.attr,
1817 	&dev_attr_tx_single_write_ops.attr,
1818 	&dev_attr_tx_multi_write_ops.attr,
1819 	&dev_attr_netto_bytes.attr,
1820 	&dev_attr_max_tx_io_time.attr,
1821 	&dev_attr_tx_pending.attr,
1822 	&dev_attr_tx_max_pending.attr,
1823 	NULL,
1824 };
1825 
1826 static struct attribute_group netiucv_stat_attr_group = {
1827 	.name  = "stats",
1828 	.attrs = netiucv_stat_attrs,
1829 };
1830 
1831 static const struct attribute_group *netiucv_attr_groups[] = {
1832 	&netiucv_stat_attr_group,
1833 	&netiucv_attr_group,
1834 	NULL,
1835 };
1836 
1837 static int netiucv_register_device(struct net_device *ndev)
1838 {
1839 	struct netiucv_priv *priv = netdev_priv(ndev);
1840 	struct device *dev = kzalloc(sizeof(struct device), GFP_KERNEL);
1841 	int ret;
1842 
1843 	IUCV_DBF_TEXT(trace, 3, __func__);
1844 
1845 	if (dev) {
1846 		dev_set_name(dev, "net%s", ndev->name);
1847 		dev->bus = &iucv_bus;
1848 		dev->parent = iucv_root;
1849 		dev->groups = netiucv_attr_groups;
1850 		/*
1851 		 * The release function could be called after the
1852 		 * module has been unloaded. It's _only_ task is to
1853 		 * free the struct. Therefore, we specify kfree()
1854 		 * directly here. (Probably a little bit obfuscating
1855 		 * but legitime ...).
1856 		 */
1857 		dev->release = (void (*)(struct device *))kfree;
1858 		dev->driver = &netiucv_driver;
1859 	} else
1860 		return -ENOMEM;
1861 
1862 	ret = device_register(dev);
1863 	if (ret) {
1864 		put_device(dev);
1865 		return ret;
1866 	}
1867 	priv->dev = dev;
1868 	dev_set_drvdata(dev, priv);
1869 	return 0;
1870 }
1871 
1872 static void netiucv_unregister_device(struct device *dev)
1873 {
1874 	IUCV_DBF_TEXT(trace, 3, __func__);
1875 	device_unregister(dev);
1876 }
1877 
1878 /**
1879  * Allocate and initialize a new connection structure.
1880  * Add it to the list of netiucv connections;
1881  */
1882 static struct iucv_connection *netiucv_new_connection(struct net_device *dev,
1883 						      char *username,
1884 						      char *userdata)
1885 {
1886 	struct iucv_connection *conn;
1887 
1888 	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1889 	if (!conn)
1890 		goto out;
1891 	skb_queue_head_init(&conn->collect_queue);
1892 	skb_queue_head_init(&conn->commit_queue);
1893 	spin_lock_init(&conn->collect_lock);
1894 	conn->max_buffsize = NETIUCV_BUFSIZE_DEFAULT;
1895 	conn->netdev = dev;
1896 
1897 	conn->rx_buff = alloc_skb(conn->max_buffsize, GFP_KERNEL | GFP_DMA);
1898 	if (!conn->rx_buff)
1899 		goto out_conn;
1900 	conn->tx_buff = alloc_skb(conn->max_buffsize, GFP_KERNEL | GFP_DMA);
1901 	if (!conn->tx_buff)
1902 		goto out_rx;
1903 	conn->fsm = init_fsm("netiucvconn", conn_state_names,
1904 			     conn_event_names, NR_CONN_STATES,
1905 			     NR_CONN_EVENTS, conn_fsm, CONN_FSM_LEN,
1906 			     GFP_KERNEL);
1907 	if (!conn->fsm)
1908 		goto out_tx;
1909 
1910 	fsm_settimer(conn->fsm, &conn->timer);
1911 	fsm_newstate(conn->fsm, CONN_STATE_INVALID);
1912 
1913 	if (userdata)
1914 		memcpy(conn->userdata, userdata, 17);
1915 	if (username) {
1916 		memcpy(conn->userid, username, 9);
1917 		fsm_newstate(conn->fsm, CONN_STATE_STOPPED);
1918 	}
1919 
1920 	write_lock_bh(&iucv_connection_rwlock);
1921 	list_add_tail(&conn->list, &iucv_connection_list);
1922 	write_unlock_bh(&iucv_connection_rwlock);
1923 	return conn;
1924 
1925 out_tx:
1926 	kfree_skb(conn->tx_buff);
1927 out_rx:
1928 	kfree_skb(conn->rx_buff);
1929 out_conn:
1930 	kfree(conn);
1931 out:
1932 	return NULL;
1933 }
1934 
1935 /**
1936  * Release a connection structure and remove it from the
1937  * list of netiucv connections.
1938  */
1939 static void netiucv_remove_connection(struct iucv_connection *conn)
1940 {
1941 
1942 	IUCV_DBF_TEXT(trace, 3, __func__);
1943 	write_lock_bh(&iucv_connection_rwlock);
1944 	list_del_init(&conn->list);
1945 	write_unlock_bh(&iucv_connection_rwlock);
1946 	fsm_deltimer(&conn->timer);
1947 	netiucv_purge_skb_queue(&conn->collect_queue);
1948 	if (conn->path) {
1949 		iucv_path_sever(conn->path, conn->userdata);
1950 		kfree(conn->path);
1951 		conn->path = NULL;
1952 	}
1953 	netiucv_purge_skb_queue(&conn->commit_queue);
1954 	kfree_fsm(conn->fsm);
1955 	kfree_skb(conn->rx_buff);
1956 	kfree_skb(conn->tx_buff);
1957 }
1958 
1959 /**
1960  * Release everything of a net device.
1961  */
1962 static void netiucv_free_netdevice(struct net_device *dev)
1963 {
1964 	struct netiucv_priv *privptr = netdev_priv(dev);
1965 
1966 	IUCV_DBF_TEXT(trace, 3, __func__);
1967 
1968 	if (!dev)
1969 		return;
1970 
1971 	if (privptr) {
1972 		if (privptr->conn)
1973 			netiucv_remove_connection(privptr->conn);
1974 		if (privptr->fsm)
1975 			kfree_fsm(privptr->fsm);
1976 		privptr->conn = NULL; privptr->fsm = NULL;
1977 		/* privptr gets freed by free_netdev() */
1978 	}
1979 	free_netdev(dev);
1980 }
1981 
1982 /**
1983  * Initialize a net device. (Called from kernel in alloc_netdev())
1984  */
1985 static const struct net_device_ops netiucv_netdev_ops = {
1986 	.ndo_open		= netiucv_open,
1987 	.ndo_stop		= netiucv_close,
1988 	.ndo_get_stats		= netiucv_stats,
1989 	.ndo_start_xmit		= netiucv_tx,
1990 	.ndo_change_mtu	   	= netiucv_change_mtu,
1991 };
1992 
1993 static void netiucv_setup_netdevice(struct net_device *dev)
1994 {
1995 	dev->mtu	         = NETIUCV_MTU_DEFAULT;
1996 	dev->destructor          = netiucv_free_netdevice;
1997 	dev->hard_header_len     = NETIUCV_HDRLEN;
1998 	dev->addr_len            = 0;
1999 	dev->type                = ARPHRD_SLIP;
2000 	dev->tx_queue_len        = NETIUCV_QUEUELEN_DEFAULT;
2001 	dev->flags	         = IFF_POINTOPOINT | IFF_NOARP;
2002 	dev->netdev_ops		 = &netiucv_netdev_ops;
2003 }
2004 
2005 /**
2006  * Allocate and initialize everything of a net device.
2007  */
2008 static struct net_device *netiucv_init_netdevice(char *username, char *userdata)
2009 {
2010 	struct netiucv_priv *privptr;
2011 	struct net_device *dev;
2012 
2013 	dev = alloc_netdev(sizeof(struct netiucv_priv), "iucv%d",
2014 			   NET_NAME_UNKNOWN, netiucv_setup_netdevice);
2015 	if (!dev)
2016 		return NULL;
2017 	rtnl_lock();
2018 	if (dev_alloc_name(dev, dev->name) < 0)
2019 		goto out_netdev;
2020 
2021 	privptr = netdev_priv(dev);
2022 	privptr->fsm = init_fsm("netiucvdev", dev_state_names,
2023 				dev_event_names, NR_DEV_STATES, NR_DEV_EVENTS,
2024 				dev_fsm, DEV_FSM_LEN, GFP_KERNEL);
2025 	if (!privptr->fsm)
2026 		goto out_netdev;
2027 
2028 	privptr->conn = netiucv_new_connection(dev, username, userdata);
2029 	if (!privptr->conn) {
2030 		IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_new_connection\n");
2031 		goto out_fsm;
2032 	}
2033 	fsm_newstate(privptr->fsm, DEV_STATE_STOPPED);
2034 	return dev;
2035 
2036 out_fsm:
2037 	kfree_fsm(privptr->fsm);
2038 out_netdev:
2039 	rtnl_unlock();
2040 	free_netdev(dev);
2041 	return NULL;
2042 }
2043 
2044 static ssize_t conn_write(struct device_driver *drv,
2045 			  const char *buf, size_t count)
2046 {
2047 	char username[9];
2048 	char userdata[17];
2049 	int rc;
2050 	struct net_device *dev;
2051 	struct netiucv_priv *priv;
2052 	struct iucv_connection *cp;
2053 
2054 	IUCV_DBF_TEXT(trace, 3, __func__);
2055 	rc = netiucv_check_user(buf, count, username, userdata);
2056 	if (rc)
2057 		return rc;
2058 
2059 	read_lock_bh(&iucv_connection_rwlock);
2060 	list_for_each_entry(cp, &iucv_connection_list, list) {
2061 		if (!strncmp(username, cp->userid, 9) &&
2062 		    !strncmp(userdata, cp->userdata, 17)) {
2063 			read_unlock_bh(&iucv_connection_rwlock);
2064 			IUCV_DBF_TEXT_(setup, 2, "conn_write: Connection to %s "
2065 				"already exists\n", netiucv_printuser(cp));
2066 			return -EEXIST;
2067 		}
2068 	}
2069 	read_unlock_bh(&iucv_connection_rwlock);
2070 
2071 	dev = netiucv_init_netdevice(username, userdata);
2072 	if (!dev) {
2073 		IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_init_netdevice\n");
2074 		return -ENODEV;
2075 	}
2076 
2077 	rc = netiucv_register_device(dev);
2078 	if (rc) {
2079 		rtnl_unlock();
2080 		IUCV_DBF_TEXT_(setup, 2,
2081 			"ret %d from netiucv_register_device\n", rc);
2082 		goto out_free_ndev;
2083 	}
2084 
2085 	/* sysfs magic */
2086 	priv = netdev_priv(dev);
2087 	SET_NETDEV_DEV(dev, priv->dev);
2088 
2089 	rc = register_netdevice(dev);
2090 	rtnl_unlock();
2091 	if (rc)
2092 		goto out_unreg;
2093 
2094 	dev_info(priv->dev, "The IUCV interface to %s has been established "
2095 			    "successfully\n",
2096 		netiucv_printuser(priv->conn));
2097 
2098 	return count;
2099 
2100 out_unreg:
2101 	netiucv_unregister_device(priv->dev);
2102 out_free_ndev:
2103 	netiucv_free_netdevice(dev);
2104 	return rc;
2105 }
2106 
2107 static DRIVER_ATTR(connection, 0200, NULL, conn_write);
2108 
2109 static ssize_t remove_write (struct device_driver *drv,
2110 			     const char *buf, size_t count)
2111 {
2112 	struct iucv_connection *cp;
2113         struct net_device *ndev;
2114         struct netiucv_priv *priv;
2115         struct device *dev;
2116         char name[IFNAMSIZ];
2117 	const char *p;
2118         int i;
2119 
2120 	IUCV_DBF_TEXT(trace, 3, __func__);
2121 
2122         if (count >= IFNAMSIZ)
2123                 count = IFNAMSIZ - 1;
2124 
2125 	for (i = 0, p = buf; i < count && *p; i++, p++) {
2126 		if (*p == '\n' || *p == ' ')
2127                         /* trailing lf, grr */
2128                         break;
2129 		name[i] = *p;
2130         }
2131         name[i] = '\0';
2132 
2133 	read_lock_bh(&iucv_connection_rwlock);
2134 	list_for_each_entry(cp, &iucv_connection_list, list) {
2135 		ndev = cp->netdev;
2136 		priv = netdev_priv(ndev);
2137                 dev = priv->dev;
2138 		if (strncmp(name, ndev->name, count))
2139 			continue;
2140 		read_unlock_bh(&iucv_connection_rwlock);
2141                 if (ndev->flags & (IFF_UP | IFF_RUNNING)) {
2142 			dev_warn(dev, "The IUCV device is connected"
2143 				" to %s and cannot be removed\n",
2144 				priv->conn->userid);
2145 			IUCV_DBF_TEXT(data, 2, "remove_write: still active\n");
2146 			return -EPERM;
2147                 }
2148                 unregister_netdev(ndev);
2149                 netiucv_unregister_device(dev);
2150                 return count;
2151         }
2152 	read_unlock_bh(&iucv_connection_rwlock);
2153 	IUCV_DBF_TEXT(data, 2, "remove_write: unknown device\n");
2154         return -EINVAL;
2155 }
2156 
2157 static DRIVER_ATTR(remove, 0200, NULL, remove_write);
2158 
2159 static struct attribute * netiucv_drv_attrs[] = {
2160 	&driver_attr_connection.attr,
2161 	&driver_attr_remove.attr,
2162 	NULL,
2163 };
2164 
2165 static struct attribute_group netiucv_drv_attr_group = {
2166 	.attrs = netiucv_drv_attrs,
2167 };
2168 
2169 static const struct attribute_group *netiucv_drv_attr_groups[] = {
2170 	&netiucv_drv_attr_group,
2171 	NULL,
2172 };
2173 
2174 static void netiucv_banner(void)
2175 {
2176 	pr_info("driver initialized\n");
2177 }
2178 
2179 static void __exit netiucv_exit(void)
2180 {
2181 	struct iucv_connection *cp;
2182 	struct net_device *ndev;
2183 	struct netiucv_priv *priv;
2184 	struct device *dev;
2185 
2186 	IUCV_DBF_TEXT(trace, 3, __func__);
2187 	while (!list_empty(&iucv_connection_list)) {
2188 		cp = list_entry(iucv_connection_list.next,
2189 				struct iucv_connection, list);
2190 		ndev = cp->netdev;
2191 		priv = netdev_priv(ndev);
2192 		dev = priv->dev;
2193 
2194 		unregister_netdev(ndev);
2195 		netiucv_unregister_device(dev);
2196 	}
2197 
2198 	device_unregister(netiucv_dev);
2199 	driver_unregister(&netiucv_driver);
2200 	iucv_unregister(&netiucv_handler, 1);
2201 	iucv_unregister_dbf_views();
2202 
2203 	pr_info("driver unloaded\n");
2204 	return;
2205 }
2206 
2207 static int __init netiucv_init(void)
2208 {
2209 	int rc;
2210 
2211 	rc = iucv_register_dbf_views();
2212 	if (rc)
2213 		goto out;
2214 	rc = iucv_register(&netiucv_handler, 1);
2215 	if (rc)
2216 		goto out_dbf;
2217 	IUCV_DBF_TEXT(trace, 3, __func__);
2218 	netiucv_driver.groups = netiucv_drv_attr_groups;
2219 	rc = driver_register(&netiucv_driver);
2220 	if (rc) {
2221 		IUCV_DBF_TEXT_(setup, 2, "ret %d from driver_register\n", rc);
2222 		goto out_iucv;
2223 	}
2224 	/* establish dummy device */
2225 	netiucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2226 	if (!netiucv_dev) {
2227 		rc = -ENOMEM;
2228 		goto out_driver;
2229 	}
2230 	dev_set_name(netiucv_dev, "netiucv");
2231 	netiucv_dev->bus = &iucv_bus;
2232 	netiucv_dev->parent = iucv_root;
2233 	netiucv_dev->release = (void (*)(struct device *))kfree;
2234 	netiucv_dev->driver = &netiucv_driver;
2235 	rc = device_register(netiucv_dev);
2236 	if (rc) {
2237 		put_device(netiucv_dev);
2238 		goto out_driver;
2239 	}
2240 	netiucv_banner();
2241 	return rc;
2242 
2243 out_driver:
2244 	driver_unregister(&netiucv_driver);
2245 out_iucv:
2246 	iucv_unregister(&netiucv_handler, 1);
2247 out_dbf:
2248 	iucv_unregister_dbf_views();
2249 out:
2250 	return rc;
2251 }
2252 
2253 module_init(netiucv_init);
2254 module_exit(netiucv_exit);
2255 MODULE_LICENSE("GPL");
2256