xref: /linux/drivers/s390/net/netiucv.c (revision c4c11dd160a8cc98f402c4e12f94b1572e822ffd)
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 /* Allow to sort out low debug levels early to avoid wasted sprints */
109 static inline int iucv_dbf_passes(debug_info_t *dbf_grp, int level)
110 {
111 	return (level <= dbf_grp->level);
112 }
113 
114 #define IUCV_DBF_TEXT_(name, level, text...) \
115 	do { \
116 		if (iucv_dbf_passes(iucv_dbf_##name, level)) { \
117 			char* __buf = get_cpu_var(iucv_dbf_txt_buf); \
118 			sprintf(__buf, text); \
119 			debug_text_event(iucv_dbf_##name, level, __buf); \
120 			put_cpu_var(iucv_dbf_txt_buf); \
121 		} \
122 	} while (0)
123 
124 #define IUCV_DBF_SPRINTF(name,level,text...) \
125 	do { \
126 		debug_sprintf_event(iucv_dbf_trace, level, ##text ); \
127 		debug_sprintf_event(iucv_dbf_trace, level, text ); \
128 	} while (0)
129 
130 /**
131  * some more debug stuff
132  */
133 #define PRINTK_HEADER " iucv: "       /* for debugging */
134 
135 /* dummy device to make sure netiucv_pm functions are called */
136 static struct device *netiucv_dev;
137 
138 static int netiucv_pm_prepare(struct device *);
139 static void netiucv_pm_complete(struct device *);
140 static int netiucv_pm_freeze(struct device *);
141 static int netiucv_pm_restore_thaw(struct device *);
142 
143 static const struct dev_pm_ops netiucv_pm_ops = {
144 	.prepare = netiucv_pm_prepare,
145 	.complete = netiucv_pm_complete,
146 	.freeze = netiucv_pm_freeze,
147 	.thaw = netiucv_pm_restore_thaw,
148 	.restore = netiucv_pm_restore_thaw,
149 };
150 
151 static struct device_driver netiucv_driver = {
152 	.owner = THIS_MODULE,
153 	.name = "netiucv",
154 	.bus  = &iucv_bus,
155 	.pm = &netiucv_pm_ops,
156 };
157 
158 static int netiucv_callback_connreq(struct iucv_path *,
159 				    u8 ipvmid[8], u8 ipuser[16]);
160 static void netiucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
161 static void netiucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
162 static void netiucv_callback_connsusp(struct iucv_path *, u8 ipuser[16]);
163 static void netiucv_callback_connres(struct iucv_path *, u8 ipuser[16]);
164 static void netiucv_callback_rx(struct iucv_path *, struct iucv_message *);
165 static void netiucv_callback_txdone(struct iucv_path *, struct iucv_message *);
166 
167 static struct iucv_handler netiucv_handler = {
168 	.path_pending	  = netiucv_callback_connreq,
169 	.path_complete	  = netiucv_callback_connack,
170 	.path_severed	  = netiucv_callback_connrej,
171 	.path_quiesced	  = netiucv_callback_connsusp,
172 	.path_resumed	  = netiucv_callback_connres,
173 	.message_pending  = netiucv_callback_rx,
174 	.message_complete = netiucv_callback_txdone
175 };
176 
177 /**
178  * Per connection profiling data
179  */
180 struct connection_profile {
181 	unsigned long maxmulti;
182 	unsigned long maxcqueue;
183 	unsigned long doios_single;
184 	unsigned long doios_multi;
185 	unsigned long txlen;
186 	unsigned long tx_time;
187 	struct timespec send_stamp;
188 	unsigned long tx_pending;
189 	unsigned long tx_max_pending;
190 };
191 
192 /**
193  * Representation of one iucv connection
194  */
195 struct iucv_connection {
196 	struct list_head	  list;
197 	struct iucv_path	  *path;
198 	struct sk_buff            *rx_buff;
199 	struct sk_buff            *tx_buff;
200 	struct sk_buff_head       collect_queue;
201 	struct sk_buff_head	  commit_queue;
202 	spinlock_t                collect_lock;
203 	int                       collect_len;
204 	int                       max_buffsize;
205 	fsm_timer                 timer;
206 	fsm_instance              *fsm;
207 	struct net_device         *netdev;
208 	struct connection_profile prof;
209 	char                      userid[9];
210 	char			  userdata[17];
211 };
212 
213 /**
214  * Linked list of all connection structs.
215  */
216 static LIST_HEAD(iucv_connection_list);
217 static DEFINE_RWLOCK(iucv_connection_rwlock);
218 
219 /**
220  * Representation of event-data for the
221  * connection state machine.
222  */
223 struct iucv_event {
224 	struct iucv_connection *conn;
225 	void                   *data;
226 };
227 
228 /**
229  * Private part of the network device structure
230  */
231 struct netiucv_priv {
232 	struct net_device_stats stats;
233 	unsigned long           tbusy;
234 	fsm_instance            *fsm;
235         struct iucv_connection  *conn;
236 	struct device           *dev;
237 	int			 pm_state;
238 };
239 
240 /**
241  * Link level header for a packet.
242  */
243 struct ll_header {
244 	u16 next;
245 };
246 
247 #define NETIUCV_HDRLEN		 (sizeof(struct ll_header))
248 #define NETIUCV_BUFSIZE_MAX	 65537
249 #define NETIUCV_BUFSIZE_DEFAULT  NETIUCV_BUFSIZE_MAX
250 #define NETIUCV_MTU_MAX          (NETIUCV_BUFSIZE_MAX - NETIUCV_HDRLEN)
251 #define NETIUCV_MTU_DEFAULT      9216
252 #define NETIUCV_QUEUELEN_DEFAULT 50
253 #define NETIUCV_TIMEOUT_5SEC     5000
254 
255 /**
256  * Compatibility macros for busy handling
257  * of network devices.
258  */
259 static inline void netiucv_clear_busy(struct net_device *dev)
260 {
261 	struct netiucv_priv *priv = netdev_priv(dev);
262 	clear_bit(0, &priv->tbusy);
263 	netif_wake_queue(dev);
264 }
265 
266 static inline int netiucv_test_and_set_busy(struct net_device *dev)
267 {
268 	struct netiucv_priv *priv = netdev_priv(dev);
269 	netif_stop_queue(dev);
270 	return test_and_set_bit(0, &priv->tbusy);
271 }
272 
273 static u8 iucvMagic_ascii[16] = {
274 	0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
275 	0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20
276 };
277 
278 static u8 iucvMagic_ebcdic[16] = {
279 	0xF0, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,
280 	0xF0, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40
281 };
282 
283 /**
284  * Convert an iucv userId to its printable
285  * form (strip whitespace at end).
286  *
287  * @param An iucv userId
288  *
289  * @returns The printable string (static data!!)
290  */
291 static char *netiucv_printname(char *name, int len)
292 {
293 	static char tmp[17];
294 	char *p = tmp;
295 	memcpy(tmp, name, len);
296 	tmp[len] = '\0';
297 	while (*p && ((p - tmp) < len) && (!isspace(*p)))
298 		p++;
299 	*p = '\0';
300 	return tmp;
301 }
302 
303 static char *netiucv_printuser(struct iucv_connection *conn)
304 {
305 	static char tmp_uid[9];
306 	static char tmp_udat[17];
307 	static char buf[100];
308 
309 	if (memcmp(conn->userdata, iucvMagic_ebcdic, 16)) {
310 		tmp_uid[8] = '\0';
311 		tmp_udat[16] = '\0';
312 		memcpy(tmp_uid, conn->userid, 8);
313 		memcpy(tmp_uid, netiucv_printname(tmp_uid, 8), 8);
314 		memcpy(tmp_udat, conn->userdata, 16);
315 		EBCASC(tmp_udat, 16);
316 		memcpy(tmp_udat, netiucv_printname(tmp_udat, 16), 16);
317 		sprintf(buf, "%s.%s", tmp_uid, tmp_udat);
318 		return buf;
319 	} else
320 		return netiucv_printname(conn->userid, 8);
321 }
322 
323 /**
324  * States of the interface statemachine.
325  */
326 enum dev_states {
327 	DEV_STATE_STOPPED,
328 	DEV_STATE_STARTWAIT,
329 	DEV_STATE_STOPWAIT,
330 	DEV_STATE_RUNNING,
331 	/**
332 	 * MUST be always the last element!!
333 	 */
334 	NR_DEV_STATES
335 };
336 
337 static const char *dev_state_names[] = {
338 	"Stopped",
339 	"StartWait",
340 	"StopWait",
341 	"Running",
342 };
343 
344 /**
345  * Events of the interface statemachine.
346  */
347 enum dev_events {
348 	DEV_EVENT_START,
349 	DEV_EVENT_STOP,
350 	DEV_EVENT_CONUP,
351 	DEV_EVENT_CONDOWN,
352 	/**
353 	 * MUST be always the last element!!
354 	 */
355 	NR_DEV_EVENTS
356 };
357 
358 static const char *dev_event_names[] = {
359 	"Start",
360 	"Stop",
361 	"Connection up",
362 	"Connection down",
363 };
364 
365 /**
366  * Events of the connection statemachine
367  */
368 enum conn_events {
369 	/**
370 	 * Events, representing callbacks from
371 	 * lowlevel iucv layer)
372 	 */
373 	CONN_EVENT_CONN_REQ,
374 	CONN_EVENT_CONN_ACK,
375 	CONN_EVENT_CONN_REJ,
376 	CONN_EVENT_CONN_SUS,
377 	CONN_EVENT_CONN_RES,
378 	CONN_EVENT_RX,
379 	CONN_EVENT_TXDONE,
380 
381 	/**
382 	 * Events, representing errors return codes from
383 	 * calls to lowlevel iucv layer
384 	 */
385 
386 	/**
387 	 * Event, representing timer expiry.
388 	 */
389 	CONN_EVENT_TIMER,
390 
391 	/**
392 	 * Events, representing commands from upper levels.
393 	 */
394 	CONN_EVENT_START,
395 	CONN_EVENT_STOP,
396 
397 	/**
398 	 * MUST be always the last element!!
399 	 */
400 	NR_CONN_EVENTS,
401 };
402 
403 static const char *conn_event_names[] = {
404 	"Remote connection request",
405 	"Remote connection acknowledge",
406 	"Remote connection reject",
407 	"Connection suspended",
408 	"Connection resumed",
409 	"Data received",
410 	"Data sent",
411 
412 	"Timer",
413 
414 	"Start",
415 	"Stop",
416 };
417 
418 /**
419  * States of the connection statemachine.
420  */
421 enum conn_states {
422 	/**
423 	 * Connection not assigned to any device,
424 	 * initial state, invalid
425 	 */
426 	CONN_STATE_INVALID,
427 
428 	/**
429 	 * Userid assigned but not operating
430 	 */
431 	CONN_STATE_STOPPED,
432 
433 	/**
434 	 * Connection registered,
435 	 * no connection request sent yet,
436 	 * no connection request received
437 	 */
438 	CONN_STATE_STARTWAIT,
439 
440 	/**
441 	 * Connection registered and connection request sent,
442 	 * no acknowledge and no connection request received yet.
443 	 */
444 	CONN_STATE_SETUPWAIT,
445 
446 	/**
447 	 * Connection up and running idle
448 	 */
449 	CONN_STATE_IDLE,
450 
451 	/**
452 	 * Data sent, awaiting CONN_EVENT_TXDONE
453 	 */
454 	CONN_STATE_TX,
455 
456 	/**
457 	 * Error during registration.
458 	 */
459 	CONN_STATE_REGERR,
460 
461 	/**
462 	 * Error during registration.
463 	 */
464 	CONN_STATE_CONNERR,
465 
466 	/**
467 	 * MUST be always the last element!!
468 	 */
469 	NR_CONN_STATES,
470 };
471 
472 static const char *conn_state_names[] = {
473 	"Invalid",
474 	"Stopped",
475 	"StartWait",
476 	"SetupWait",
477 	"Idle",
478 	"TX",
479 	"Terminating",
480 	"Registration error",
481 	"Connect error",
482 };
483 
484 
485 /**
486  * Debug Facility Stuff
487  */
488 static debug_info_t *iucv_dbf_setup = NULL;
489 static debug_info_t *iucv_dbf_data = NULL;
490 static debug_info_t *iucv_dbf_trace = NULL;
491 
492 DEFINE_PER_CPU(char[256], iucv_dbf_txt_buf);
493 
494 static void iucv_unregister_dbf_views(void)
495 {
496 	if (iucv_dbf_setup)
497 		debug_unregister(iucv_dbf_setup);
498 	if (iucv_dbf_data)
499 		debug_unregister(iucv_dbf_data);
500 	if (iucv_dbf_trace)
501 		debug_unregister(iucv_dbf_trace);
502 }
503 static int iucv_register_dbf_views(void)
504 {
505 	iucv_dbf_setup = debug_register(IUCV_DBF_SETUP_NAME,
506 					IUCV_DBF_SETUP_PAGES,
507 					IUCV_DBF_SETUP_NR_AREAS,
508 					IUCV_DBF_SETUP_LEN);
509 	iucv_dbf_data = debug_register(IUCV_DBF_DATA_NAME,
510 				       IUCV_DBF_DATA_PAGES,
511 				       IUCV_DBF_DATA_NR_AREAS,
512 				       IUCV_DBF_DATA_LEN);
513 	iucv_dbf_trace = debug_register(IUCV_DBF_TRACE_NAME,
514 					IUCV_DBF_TRACE_PAGES,
515 					IUCV_DBF_TRACE_NR_AREAS,
516 					IUCV_DBF_TRACE_LEN);
517 
518 	if ((iucv_dbf_setup == NULL) || (iucv_dbf_data == NULL) ||
519 	    (iucv_dbf_trace == NULL)) {
520 		iucv_unregister_dbf_views();
521 		return -ENOMEM;
522 	}
523 	debug_register_view(iucv_dbf_setup, &debug_hex_ascii_view);
524 	debug_set_level(iucv_dbf_setup, IUCV_DBF_SETUP_LEVEL);
525 
526 	debug_register_view(iucv_dbf_data, &debug_hex_ascii_view);
527 	debug_set_level(iucv_dbf_data, IUCV_DBF_DATA_LEVEL);
528 
529 	debug_register_view(iucv_dbf_trace, &debug_hex_ascii_view);
530 	debug_set_level(iucv_dbf_trace, IUCV_DBF_TRACE_LEVEL);
531 
532 	return 0;
533 }
534 
535 /*
536  * Callback-wrappers, called from lowlevel iucv layer.
537  */
538 
539 static void netiucv_callback_rx(struct iucv_path *path,
540 				struct iucv_message *msg)
541 {
542 	struct iucv_connection *conn = path->private;
543 	struct iucv_event ev;
544 
545 	ev.conn = conn;
546 	ev.data = msg;
547 	fsm_event(conn->fsm, CONN_EVENT_RX, &ev);
548 }
549 
550 static void netiucv_callback_txdone(struct iucv_path *path,
551 				    struct iucv_message *msg)
552 {
553 	struct iucv_connection *conn = path->private;
554 	struct iucv_event ev;
555 
556 	ev.conn = conn;
557 	ev.data = msg;
558 	fsm_event(conn->fsm, CONN_EVENT_TXDONE, &ev);
559 }
560 
561 static void netiucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
562 {
563 	struct iucv_connection *conn = path->private;
564 
565 	fsm_event(conn->fsm, CONN_EVENT_CONN_ACK, conn);
566 }
567 
568 static int netiucv_callback_connreq(struct iucv_path *path,
569 				    u8 ipvmid[8], u8 ipuser[16])
570 {
571 	struct iucv_connection *conn = path->private;
572 	struct iucv_event ev;
573 	static char tmp_user[9];
574 	static char tmp_udat[17];
575 	int rc;
576 
577 	rc = -EINVAL;
578 	memcpy(tmp_user, netiucv_printname(ipvmid, 8), 8);
579 	memcpy(tmp_udat, ipuser, 16);
580 	EBCASC(tmp_udat, 16);
581 	read_lock_bh(&iucv_connection_rwlock);
582 	list_for_each_entry(conn, &iucv_connection_list, list) {
583 		if (strncmp(ipvmid, conn->userid, 8) ||
584 		    strncmp(ipuser, conn->userdata, 16))
585 			continue;
586 		/* Found a matching connection for this path. */
587 		conn->path = path;
588 		ev.conn = conn;
589 		ev.data = path;
590 		fsm_event(conn->fsm, CONN_EVENT_CONN_REQ, &ev);
591 		rc = 0;
592 	}
593 	IUCV_DBF_TEXT_(setup, 2, "Connection requested for %s.%s\n",
594 		       tmp_user, netiucv_printname(tmp_udat, 16));
595 	read_unlock_bh(&iucv_connection_rwlock);
596 	return rc;
597 }
598 
599 static void netiucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
600 {
601 	struct iucv_connection *conn = path->private;
602 
603 	fsm_event(conn->fsm, CONN_EVENT_CONN_REJ, conn);
604 }
605 
606 static void netiucv_callback_connsusp(struct iucv_path *path, u8 ipuser[16])
607 {
608 	struct iucv_connection *conn = path->private;
609 
610 	fsm_event(conn->fsm, CONN_EVENT_CONN_SUS, conn);
611 }
612 
613 static void netiucv_callback_connres(struct iucv_path *path, u8 ipuser[16])
614 {
615 	struct iucv_connection *conn = path->private;
616 
617 	fsm_event(conn->fsm, CONN_EVENT_CONN_RES, conn);
618 }
619 
620 /**
621  * NOP action for statemachines
622  */
623 static void netiucv_action_nop(fsm_instance *fi, int event, void *arg)
624 {
625 }
626 
627 /*
628  * Actions of the connection statemachine
629  */
630 
631 /**
632  * netiucv_unpack_skb
633  * @conn: The connection where this skb has been received.
634  * @pskb: The received skb.
635  *
636  * Unpack a just received skb and hand it over to upper layers.
637  * Helper function for conn_action_rx.
638  */
639 static void netiucv_unpack_skb(struct iucv_connection *conn,
640 			       struct sk_buff *pskb)
641 {
642 	struct net_device     *dev = conn->netdev;
643 	struct netiucv_priv   *privptr = netdev_priv(dev);
644 	u16 offset = 0;
645 
646 	skb_put(pskb, NETIUCV_HDRLEN);
647 	pskb->dev = dev;
648 	pskb->ip_summed = CHECKSUM_NONE;
649 	pskb->protocol = ntohs(ETH_P_IP);
650 
651 	while (1) {
652 		struct sk_buff *skb;
653 		struct ll_header *header = (struct ll_header *) pskb->data;
654 
655 		if (!header->next)
656 			break;
657 
658 		skb_pull(pskb, NETIUCV_HDRLEN);
659 		header->next -= offset;
660 		offset += header->next;
661 		header->next -= NETIUCV_HDRLEN;
662 		if (skb_tailroom(pskb) < header->next) {
663 			IUCV_DBF_TEXT_(data, 2, "Illegal next field: %d > %d\n",
664 				header->next, skb_tailroom(pskb));
665 			return;
666 		}
667 		skb_put(pskb, header->next);
668 		skb_reset_mac_header(pskb);
669 		skb = dev_alloc_skb(pskb->len);
670 		if (!skb) {
671 			IUCV_DBF_TEXT(data, 2,
672 				"Out of memory in netiucv_unpack_skb\n");
673 			privptr->stats.rx_dropped++;
674 			return;
675 		}
676 		skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
677 					  pskb->len);
678 		skb_reset_mac_header(skb);
679 		skb->dev = pskb->dev;
680 		skb->protocol = pskb->protocol;
681 		pskb->ip_summed = CHECKSUM_UNNECESSARY;
682 		privptr->stats.rx_packets++;
683 		privptr->stats.rx_bytes += skb->len;
684 		/*
685 		 * Since receiving is always initiated from a tasklet (in iucv.c),
686 		 * we must use netif_rx_ni() instead of netif_rx()
687 		 */
688 		netif_rx_ni(skb);
689 		skb_pull(pskb, header->next);
690 		skb_put(pskb, NETIUCV_HDRLEN);
691 	}
692 }
693 
694 static void conn_action_rx(fsm_instance *fi, int event, void *arg)
695 {
696 	struct iucv_event *ev = arg;
697 	struct iucv_connection *conn = ev->conn;
698 	struct iucv_message *msg = ev->data;
699 	struct netiucv_priv *privptr = netdev_priv(conn->netdev);
700 	int rc;
701 
702 	IUCV_DBF_TEXT(trace, 4, __func__);
703 
704 	if (!conn->netdev) {
705 		iucv_message_reject(conn->path, msg);
706 		IUCV_DBF_TEXT(data, 2,
707 			      "Received data for unlinked connection\n");
708 		return;
709 	}
710 	if (msg->length > conn->max_buffsize) {
711 		iucv_message_reject(conn->path, msg);
712 		privptr->stats.rx_dropped++;
713 		IUCV_DBF_TEXT_(data, 2, "msglen %d > max_buffsize %d\n",
714 			       msg->length, conn->max_buffsize);
715 		return;
716 	}
717 	conn->rx_buff->data = conn->rx_buff->head;
718 	skb_reset_tail_pointer(conn->rx_buff);
719 	conn->rx_buff->len = 0;
720 	rc = iucv_message_receive(conn->path, msg, 0, conn->rx_buff->data,
721 				  msg->length, NULL);
722 	if (rc || msg->length < 5) {
723 		privptr->stats.rx_errors++;
724 		IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_receive\n", rc);
725 		return;
726 	}
727 	netiucv_unpack_skb(conn, conn->rx_buff);
728 }
729 
730 static void conn_action_txdone(fsm_instance *fi, int event, void *arg)
731 {
732 	struct iucv_event *ev = arg;
733 	struct iucv_connection *conn = ev->conn;
734 	struct iucv_message *msg = ev->data;
735 	struct iucv_message txmsg;
736 	struct netiucv_priv *privptr = NULL;
737 	u32 single_flag = msg->tag;
738 	u32 txbytes = 0;
739 	u32 txpackets = 0;
740 	u32 stat_maxcq = 0;
741 	struct sk_buff *skb;
742 	unsigned long saveflags;
743 	struct ll_header header;
744 	int rc;
745 
746 	IUCV_DBF_TEXT(trace, 4, __func__);
747 
748 	if (conn && conn->netdev)
749 		privptr = netdev_priv(conn->netdev);
750 	conn->prof.tx_pending--;
751 	if (single_flag) {
752 		if ((skb = skb_dequeue(&conn->commit_queue))) {
753 			atomic_dec(&skb->users);
754 			if (privptr) {
755 				privptr->stats.tx_packets++;
756 				privptr->stats.tx_bytes +=
757 					(skb->len - NETIUCV_HDRLEN
758 						  - NETIUCV_HDRLEN);
759 			}
760 			dev_kfree_skb_any(skb);
761 		}
762 	}
763 	conn->tx_buff->data = conn->tx_buff->head;
764 	skb_reset_tail_pointer(conn->tx_buff);
765 	conn->tx_buff->len = 0;
766 	spin_lock_irqsave(&conn->collect_lock, saveflags);
767 	while ((skb = skb_dequeue(&conn->collect_queue))) {
768 		header.next = conn->tx_buff->len + skb->len + NETIUCV_HDRLEN;
769 		memcpy(skb_put(conn->tx_buff, NETIUCV_HDRLEN), &header,
770 		       NETIUCV_HDRLEN);
771 		skb_copy_from_linear_data(skb,
772 					  skb_put(conn->tx_buff, skb->len),
773 					  skb->len);
774 		txbytes += skb->len;
775 		txpackets++;
776 		stat_maxcq++;
777 		atomic_dec(&skb->users);
778 		dev_kfree_skb_any(skb);
779 	}
780 	if (conn->collect_len > conn->prof.maxmulti)
781 		conn->prof.maxmulti = conn->collect_len;
782 	conn->collect_len = 0;
783 	spin_unlock_irqrestore(&conn->collect_lock, saveflags);
784 	if (conn->tx_buff->len == 0) {
785 		fsm_newstate(fi, CONN_STATE_IDLE);
786 		return;
787 	}
788 
789 	header.next = 0;
790 	memcpy(skb_put(conn->tx_buff, NETIUCV_HDRLEN), &header, NETIUCV_HDRLEN);
791 	conn->prof.send_stamp = current_kernel_time();
792 	txmsg.class = 0;
793 	txmsg.tag = 0;
794 	rc = iucv_message_send(conn->path, &txmsg, 0, 0,
795 			       conn->tx_buff->data, conn->tx_buff->len);
796 	conn->prof.doios_multi++;
797 	conn->prof.txlen += conn->tx_buff->len;
798 	conn->prof.tx_pending++;
799 	if (conn->prof.tx_pending > conn->prof.tx_max_pending)
800 		conn->prof.tx_max_pending = conn->prof.tx_pending;
801 	if (rc) {
802 		conn->prof.tx_pending--;
803 		fsm_newstate(fi, CONN_STATE_IDLE);
804 		if (privptr)
805 			privptr->stats.tx_errors += txpackets;
806 		IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_send\n", rc);
807 	} else {
808 		if (privptr) {
809 			privptr->stats.tx_packets += txpackets;
810 			privptr->stats.tx_bytes += txbytes;
811 		}
812 		if (stat_maxcq > conn->prof.maxcqueue)
813 			conn->prof.maxcqueue = stat_maxcq;
814 	}
815 }
816 
817 static void conn_action_connaccept(fsm_instance *fi, int event, void *arg)
818 {
819 	struct iucv_event *ev = arg;
820 	struct iucv_connection *conn = ev->conn;
821 	struct iucv_path *path = ev->data;
822 	struct net_device *netdev = conn->netdev;
823 	struct netiucv_priv *privptr = netdev_priv(netdev);
824 	int rc;
825 
826 	IUCV_DBF_TEXT(trace, 3, __func__);
827 
828 	conn->path = path;
829 	path->msglim = NETIUCV_QUEUELEN_DEFAULT;
830 	path->flags = 0;
831 	rc = iucv_path_accept(path, &netiucv_handler, conn->userdata , conn);
832 	if (rc) {
833 		IUCV_DBF_TEXT_(setup, 2, "rc %d from iucv_accept", rc);
834 		return;
835 	}
836 	fsm_newstate(fi, CONN_STATE_IDLE);
837 	netdev->tx_queue_len = conn->path->msglim;
838 	fsm_event(privptr->fsm, DEV_EVENT_CONUP, netdev);
839 }
840 
841 static void conn_action_connreject(fsm_instance *fi, int event, void *arg)
842 {
843 	struct iucv_event *ev = arg;
844 	struct iucv_path *path = ev->data;
845 
846 	IUCV_DBF_TEXT(trace, 3, __func__);
847 	iucv_path_sever(path, NULL);
848 }
849 
850 static void conn_action_connack(fsm_instance *fi, int event, void *arg)
851 {
852 	struct iucv_connection *conn = arg;
853 	struct net_device *netdev = conn->netdev;
854 	struct netiucv_priv *privptr = netdev_priv(netdev);
855 
856 	IUCV_DBF_TEXT(trace, 3, __func__);
857 	fsm_deltimer(&conn->timer);
858 	fsm_newstate(fi, CONN_STATE_IDLE);
859 	netdev->tx_queue_len = conn->path->msglim;
860 	fsm_event(privptr->fsm, DEV_EVENT_CONUP, netdev);
861 }
862 
863 static void conn_action_conntimsev(fsm_instance *fi, int event, void *arg)
864 {
865 	struct iucv_connection *conn = arg;
866 
867 	IUCV_DBF_TEXT(trace, 3, __func__);
868 	fsm_deltimer(&conn->timer);
869 	iucv_path_sever(conn->path, conn->userdata);
870 	fsm_newstate(fi, CONN_STATE_STARTWAIT);
871 }
872 
873 static void conn_action_connsever(fsm_instance *fi, int event, void *arg)
874 {
875 	struct iucv_connection *conn = arg;
876 	struct net_device *netdev = conn->netdev;
877 	struct netiucv_priv *privptr = netdev_priv(netdev);
878 
879 	IUCV_DBF_TEXT(trace, 3, __func__);
880 
881 	fsm_deltimer(&conn->timer);
882 	iucv_path_sever(conn->path, conn->userdata);
883 	dev_info(privptr->dev, "The peer z/VM guest %s has closed the "
884 			       "connection\n", netiucv_printuser(conn));
885 	IUCV_DBF_TEXT(data, 2,
886 		      "conn_action_connsever: Remote dropped connection\n");
887 	fsm_newstate(fi, CONN_STATE_STARTWAIT);
888 	fsm_event(privptr->fsm, DEV_EVENT_CONDOWN, netdev);
889 }
890 
891 static void conn_action_start(fsm_instance *fi, int event, void *arg)
892 {
893 	struct iucv_connection *conn = arg;
894 	struct net_device *netdev = conn->netdev;
895 	struct netiucv_priv *privptr = netdev_priv(netdev);
896 	int rc;
897 
898 	IUCV_DBF_TEXT(trace, 3, __func__);
899 
900 	fsm_newstate(fi, CONN_STATE_STARTWAIT);
901 
902 	/*
903 	 * We must set the state before calling iucv_connect because the
904 	 * callback handler could be called at any point after the connection
905 	 * request is sent
906 	 */
907 
908 	fsm_newstate(fi, CONN_STATE_SETUPWAIT);
909 	conn->path = iucv_path_alloc(NETIUCV_QUEUELEN_DEFAULT, 0, GFP_KERNEL);
910 	IUCV_DBF_TEXT_(setup, 2, "%s: connecting to %s ...\n",
911 		netdev->name, netiucv_printuser(conn));
912 
913 	rc = iucv_path_connect(conn->path, &netiucv_handler, conn->userid,
914 			       NULL, conn->userdata, conn);
915 	switch (rc) {
916 	case 0:
917 		netdev->tx_queue_len = conn->path->msglim;
918 		fsm_addtimer(&conn->timer, NETIUCV_TIMEOUT_5SEC,
919 			     CONN_EVENT_TIMER, conn);
920 		return;
921 	case 11:
922 		dev_warn(privptr->dev,
923 			"The IUCV device failed to connect to z/VM guest %s\n",
924 			netiucv_printname(conn->userid, 8));
925 		fsm_newstate(fi, CONN_STATE_STARTWAIT);
926 		break;
927 	case 12:
928 		dev_warn(privptr->dev,
929 			"The IUCV device failed to connect to the peer on z/VM"
930 			" guest %s\n", netiucv_printname(conn->userid, 8));
931 		fsm_newstate(fi, CONN_STATE_STARTWAIT);
932 		break;
933 	case 13:
934 		dev_err(privptr->dev,
935 			"Connecting the IUCV device would exceed the maximum"
936 			" number of IUCV connections\n");
937 		fsm_newstate(fi, CONN_STATE_CONNERR);
938 		break;
939 	case 14:
940 		dev_err(privptr->dev,
941 			"z/VM guest %s has too many IUCV connections"
942 			" to connect with the IUCV device\n",
943 			netiucv_printname(conn->userid, 8));
944 		fsm_newstate(fi, CONN_STATE_CONNERR);
945 		break;
946 	case 15:
947 		dev_err(privptr->dev,
948 			"The IUCV device cannot connect to a z/VM guest with no"
949 			" IUCV authorization\n");
950 		fsm_newstate(fi, CONN_STATE_CONNERR);
951 		break;
952 	default:
953 		dev_err(privptr->dev,
954 			"Connecting the IUCV device failed with error %d\n",
955 			rc);
956 		fsm_newstate(fi, CONN_STATE_CONNERR);
957 		break;
958 	}
959 	IUCV_DBF_TEXT_(setup, 5, "iucv_connect rc is %d\n", rc);
960 	kfree(conn->path);
961 	conn->path = NULL;
962 }
963 
964 static void netiucv_purge_skb_queue(struct sk_buff_head *q)
965 {
966 	struct sk_buff *skb;
967 
968 	while ((skb = skb_dequeue(q))) {
969 		atomic_dec(&skb->users);
970 		dev_kfree_skb_any(skb);
971 	}
972 }
973 
974 static void conn_action_stop(fsm_instance *fi, int event, void *arg)
975 {
976 	struct iucv_event *ev = arg;
977 	struct iucv_connection *conn = ev->conn;
978 	struct net_device *netdev = conn->netdev;
979 	struct netiucv_priv *privptr = netdev_priv(netdev);
980 
981 	IUCV_DBF_TEXT(trace, 3, __func__);
982 
983 	fsm_deltimer(&conn->timer);
984 	fsm_newstate(fi, CONN_STATE_STOPPED);
985 	netiucv_purge_skb_queue(&conn->collect_queue);
986 	if (conn->path) {
987 		IUCV_DBF_TEXT(trace, 5, "calling iucv_path_sever\n");
988 		iucv_path_sever(conn->path, conn->userdata);
989 		kfree(conn->path);
990 		conn->path = NULL;
991 	}
992 	netiucv_purge_skb_queue(&conn->commit_queue);
993 	fsm_event(privptr->fsm, DEV_EVENT_CONDOWN, netdev);
994 }
995 
996 static void conn_action_inval(fsm_instance *fi, int event, void *arg)
997 {
998 	struct iucv_connection *conn = arg;
999 	struct net_device *netdev = conn->netdev;
1000 
1001 	IUCV_DBF_TEXT_(data, 2, "%s('%s'): conn_action_inval called\n",
1002 		netdev->name, conn->userid);
1003 }
1004 
1005 static const fsm_node conn_fsm[] = {
1006 	{ CONN_STATE_INVALID,   CONN_EVENT_START,    conn_action_inval      },
1007 	{ CONN_STATE_STOPPED,   CONN_EVENT_START,    conn_action_start      },
1008 
1009 	{ CONN_STATE_STOPPED,   CONN_EVENT_STOP,     conn_action_stop       },
1010 	{ CONN_STATE_STARTWAIT, CONN_EVENT_STOP,     conn_action_stop       },
1011 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_STOP,     conn_action_stop       },
1012 	{ CONN_STATE_IDLE,      CONN_EVENT_STOP,     conn_action_stop       },
1013 	{ CONN_STATE_TX,        CONN_EVENT_STOP,     conn_action_stop       },
1014 	{ CONN_STATE_REGERR,    CONN_EVENT_STOP,     conn_action_stop       },
1015 	{ CONN_STATE_CONNERR,   CONN_EVENT_STOP,     conn_action_stop       },
1016 
1017 	{ CONN_STATE_STOPPED,   CONN_EVENT_CONN_REQ, conn_action_connreject },
1018         { CONN_STATE_STARTWAIT, CONN_EVENT_CONN_REQ, conn_action_connaccept },
1019 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_REQ, conn_action_connaccept },
1020 	{ CONN_STATE_IDLE,      CONN_EVENT_CONN_REQ, conn_action_connreject },
1021 	{ CONN_STATE_TX,        CONN_EVENT_CONN_REQ, conn_action_connreject },
1022 
1023 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_ACK, conn_action_connack    },
1024 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_TIMER,    conn_action_conntimsev },
1025 
1026 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_REJ, conn_action_connsever  },
1027 	{ CONN_STATE_IDLE,      CONN_EVENT_CONN_REJ, conn_action_connsever  },
1028 	{ CONN_STATE_TX,        CONN_EVENT_CONN_REJ, conn_action_connsever  },
1029 
1030 	{ CONN_STATE_IDLE,      CONN_EVENT_RX,       conn_action_rx         },
1031 	{ CONN_STATE_TX,        CONN_EVENT_RX,       conn_action_rx         },
1032 
1033 	{ CONN_STATE_TX,        CONN_EVENT_TXDONE,   conn_action_txdone     },
1034 	{ CONN_STATE_IDLE,      CONN_EVENT_TXDONE,   conn_action_txdone     },
1035 };
1036 
1037 static const int CONN_FSM_LEN = sizeof(conn_fsm) / sizeof(fsm_node);
1038 
1039 
1040 /*
1041  * Actions for interface - statemachine.
1042  */
1043 
1044 /**
1045  * dev_action_start
1046  * @fi: An instance of an interface statemachine.
1047  * @event: The event, just happened.
1048  * @arg: Generic pointer, casted from struct net_device * upon call.
1049  *
1050  * Startup connection by sending CONN_EVENT_START to it.
1051  */
1052 static void dev_action_start(fsm_instance *fi, int event, void *arg)
1053 {
1054 	struct net_device   *dev = arg;
1055 	struct netiucv_priv *privptr = netdev_priv(dev);
1056 
1057 	IUCV_DBF_TEXT(trace, 3, __func__);
1058 
1059 	fsm_newstate(fi, DEV_STATE_STARTWAIT);
1060 	fsm_event(privptr->conn->fsm, CONN_EVENT_START, privptr->conn);
1061 }
1062 
1063 /**
1064  * Shutdown connection by sending CONN_EVENT_STOP to it.
1065  *
1066  * @param fi    An instance of an interface statemachine.
1067  * @param event The event, just happened.
1068  * @param arg   Generic pointer, casted from struct net_device * upon call.
1069  */
1070 static void
1071 dev_action_stop(fsm_instance *fi, int event, void *arg)
1072 {
1073 	struct net_device   *dev = arg;
1074 	struct netiucv_priv *privptr = netdev_priv(dev);
1075 	struct iucv_event   ev;
1076 
1077 	IUCV_DBF_TEXT(trace, 3, __func__);
1078 
1079 	ev.conn = privptr->conn;
1080 
1081 	fsm_newstate(fi, DEV_STATE_STOPWAIT);
1082 	fsm_event(privptr->conn->fsm, CONN_EVENT_STOP, &ev);
1083 }
1084 
1085 /**
1086  * Called from connection statemachine
1087  * when a connection is up and running.
1088  *
1089  * @param fi    An instance of an interface statemachine.
1090  * @param event The event, just happened.
1091  * @param arg   Generic pointer, casted from struct net_device * upon call.
1092  */
1093 static void
1094 dev_action_connup(fsm_instance *fi, int event, void *arg)
1095 {
1096 	struct net_device   *dev = arg;
1097 	struct netiucv_priv *privptr = netdev_priv(dev);
1098 
1099 	IUCV_DBF_TEXT(trace, 3, __func__);
1100 
1101 	switch (fsm_getstate(fi)) {
1102 		case DEV_STATE_STARTWAIT:
1103 			fsm_newstate(fi, DEV_STATE_RUNNING);
1104 			dev_info(privptr->dev,
1105 				"The IUCV device has been connected"
1106 				" successfully to %s\n",
1107 				netiucv_printuser(privptr->conn));
1108 			IUCV_DBF_TEXT(setup, 3,
1109 				"connection is up and running\n");
1110 			break;
1111 		case DEV_STATE_STOPWAIT:
1112 			IUCV_DBF_TEXT(data, 2,
1113 				"dev_action_connup: in DEV_STATE_STOPWAIT\n");
1114 			break;
1115 	}
1116 }
1117 
1118 /**
1119  * Called from connection statemachine
1120  * when a connection has been shutdown.
1121  *
1122  * @param fi    An instance of an interface statemachine.
1123  * @param event The event, just happened.
1124  * @param arg   Generic pointer, casted from struct net_device * upon call.
1125  */
1126 static void
1127 dev_action_conndown(fsm_instance *fi, int event, void *arg)
1128 {
1129 	IUCV_DBF_TEXT(trace, 3, __func__);
1130 
1131 	switch (fsm_getstate(fi)) {
1132 		case DEV_STATE_RUNNING:
1133 			fsm_newstate(fi, DEV_STATE_STARTWAIT);
1134 			break;
1135 		case DEV_STATE_STOPWAIT:
1136 			fsm_newstate(fi, DEV_STATE_STOPPED);
1137 			IUCV_DBF_TEXT(setup, 3, "connection is down\n");
1138 			break;
1139 	}
1140 }
1141 
1142 static const fsm_node dev_fsm[] = {
1143 	{ DEV_STATE_STOPPED,    DEV_EVENT_START,   dev_action_start    },
1144 
1145 	{ DEV_STATE_STOPWAIT,   DEV_EVENT_START,   dev_action_start    },
1146 	{ DEV_STATE_STOPWAIT,   DEV_EVENT_CONDOWN, dev_action_conndown },
1147 
1148 	{ DEV_STATE_STARTWAIT,  DEV_EVENT_STOP,    dev_action_stop     },
1149 	{ DEV_STATE_STARTWAIT,  DEV_EVENT_CONUP,   dev_action_connup   },
1150 
1151 	{ DEV_STATE_RUNNING,    DEV_EVENT_STOP,    dev_action_stop     },
1152 	{ DEV_STATE_RUNNING,    DEV_EVENT_CONDOWN, dev_action_conndown },
1153 	{ DEV_STATE_RUNNING,    DEV_EVENT_CONUP,   netiucv_action_nop  },
1154 };
1155 
1156 static const int DEV_FSM_LEN = sizeof(dev_fsm) / sizeof(fsm_node);
1157 
1158 /**
1159  * Transmit a packet.
1160  * This is a helper function for netiucv_tx().
1161  *
1162  * @param conn Connection to be used for sending.
1163  * @param skb Pointer to struct sk_buff of packet to send.
1164  *            The linklevel header has already been set up
1165  *            by netiucv_tx().
1166  *
1167  * @return 0 on success, -ERRNO on failure. (Never fails.)
1168  */
1169 static int netiucv_transmit_skb(struct iucv_connection *conn,
1170 				struct sk_buff *skb)
1171 {
1172 	struct iucv_message msg;
1173 	unsigned long saveflags;
1174 	struct ll_header header;
1175 	int rc;
1176 
1177 	if (fsm_getstate(conn->fsm) != CONN_STATE_IDLE) {
1178 		int l = skb->len + NETIUCV_HDRLEN;
1179 
1180 		spin_lock_irqsave(&conn->collect_lock, saveflags);
1181 		if (conn->collect_len + l >
1182 		    (conn->max_buffsize - NETIUCV_HDRLEN)) {
1183 			rc = -EBUSY;
1184 			IUCV_DBF_TEXT(data, 2,
1185 				      "EBUSY from netiucv_transmit_skb\n");
1186 		} else {
1187 			atomic_inc(&skb->users);
1188 			skb_queue_tail(&conn->collect_queue, skb);
1189 			conn->collect_len += l;
1190 			rc = 0;
1191 		}
1192 		spin_unlock_irqrestore(&conn->collect_lock, saveflags);
1193 	} else {
1194 		struct sk_buff *nskb = skb;
1195 		/**
1196 		 * Copy the skb to a new allocated skb in lowmem only if the
1197 		 * data is located above 2G in memory or tailroom is < 2.
1198 		 */
1199 		unsigned long hi = ((unsigned long)(skb_tail_pointer(skb) +
1200 				    NETIUCV_HDRLEN)) >> 31;
1201 		int copied = 0;
1202 		if (hi || (skb_tailroom(skb) < 2)) {
1203 			nskb = alloc_skb(skb->len + NETIUCV_HDRLEN +
1204 					 NETIUCV_HDRLEN, GFP_ATOMIC | GFP_DMA);
1205 			if (!nskb) {
1206 				IUCV_DBF_TEXT(data, 2, "alloc_skb failed\n");
1207 				rc = -ENOMEM;
1208 				return rc;
1209 			} else {
1210 				skb_reserve(nskb, NETIUCV_HDRLEN);
1211 				memcpy(skb_put(nskb, skb->len),
1212 				       skb->data, skb->len);
1213 			}
1214 			copied = 1;
1215 		}
1216 		/**
1217 		 * skb now is below 2G and has enough room. Add headers.
1218 		 */
1219 		header.next = nskb->len + NETIUCV_HDRLEN;
1220 		memcpy(skb_push(nskb, NETIUCV_HDRLEN), &header, NETIUCV_HDRLEN);
1221 		header.next = 0;
1222 		memcpy(skb_put(nskb, NETIUCV_HDRLEN), &header,  NETIUCV_HDRLEN);
1223 
1224 		fsm_newstate(conn->fsm, CONN_STATE_TX);
1225 		conn->prof.send_stamp = current_kernel_time();
1226 
1227 		msg.tag = 1;
1228 		msg.class = 0;
1229 		rc = iucv_message_send(conn->path, &msg, 0, 0,
1230 				       nskb->data, nskb->len);
1231 		conn->prof.doios_single++;
1232 		conn->prof.txlen += skb->len;
1233 		conn->prof.tx_pending++;
1234 		if (conn->prof.tx_pending > conn->prof.tx_max_pending)
1235 			conn->prof.tx_max_pending = conn->prof.tx_pending;
1236 		if (rc) {
1237 			struct netiucv_priv *privptr;
1238 			fsm_newstate(conn->fsm, CONN_STATE_IDLE);
1239 			conn->prof.tx_pending--;
1240 			privptr = netdev_priv(conn->netdev);
1241 			if (privptr)
1242 				privptr->stats.tx_errors++;
1243 			if (copied)
1244 				dev_kfree_skb(nskb);
1245 			else {
1246 				/**
1247 				 * Remove our headers. They get added
1248 				 * again on retransmit.
1249 				 */
1250 				skb_pull(skb, NETIUCV_HDRLEN);
1251 				skb_trim(skb, skb->len - NETIUCV_HDRLEN);
1252 			}
1253 			IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_send\n", rc);
1254 		} else {
1255 			if (copied)
1256 				dev_kfree_skb(skb);
1257 			atomic_inc(&nskb->users);
1258 			skb_queue_tail(&conn->commit_queue, nskb);
1259 		}
1260 	}
1261 
1262 	return rc;
1263 }
1264 
1265 /*
1266  * Interface API for upper network layers
1267  */
1268 
1269 /**
1270  * Open an interface.
1271  * Called from generic network layer when ifconfig up is run.
1272  *
1273  * @param dev Pointer to interface struct.
1274  *
1275  * @return 0 on success, -ERRNO on failure. (Never fails.)
1276  */
1277 static int netiucv_open(struct net_device *dev)
1278 {
1279 	struct netiucv_priv *priv = netdev_priv(dev);
1280 
1281 	fsm_event(priv->fsm, DEV_EVENT_START, dev);
1282 	return 0;
1283 }
1284 
1285 /**
1286  * Close an interface.
1287  * Called from generic network layer when ifconfig down is run.
1288  *
1289  * @param dev Pointer to interface struct.
1290  *
1291  * @return 0 on success, -ERRNO on failure. (Never fails.)
1292  */
1293 static int netiucv_close(struct net_device *dev)
1294 {
1295 	struct netiucv_priv *priv = netdev_priv(dev);
1296 
1297 	fsm_event(priv->fsm, DEV_EVENT_STOP, dev);
1298 	return 0;
1299 }
1300 
1301 static int netiucv_pm_prepare(struct device *dev)
1302 {
1303 	IUCV_DBF_TEXT(trace, 3, __func__);
1304 	return 0;
1305 }
1306 
1307 static void netiucv_pm_complete(struct device *dev)
1308 {
1309 	IUCV_DBF_TEXT(trace, 3, __func__);
1310 	return;
1311 }
1312 
1313 /**
1314  * netiucv_pm_freeze() - Freeze PM callback
1315  * @dev:	netiucv device
1316  *
1317  * close open netiucv interfaces
1318  */
1319 static int netiucv_pm_freeze(struct device *dev)
1320 {
1321 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1322 	struct net_device *ndev = NULL;
1323 	int rc = 0;
1324 
1325 	IUCV_DBF_TEXT(trace, 3, __func__);
1326 	if (priv && priv->conn)
1327 		ndev = priv->conn->netdev;
1328 	if (!ndev)
1329 		goto out;
1330 	netif_device_detach(ndev);
1331 	priv->pm_state = fsm_getstate(priv->fsm);
1332 	rc = netiucv_close(ndev);
1333 out:
1334 	return rc;
1335 }
1336 
1337 /**
1338  * netiucv_pm_restore_thaw() - Thaw and restore PM callback
1339  * @dev:	netiucv device
1340  *
1341  * re-open netiucv interfaces closed during freeze
1342  */
1343 static int netiucv_pm_restore_thaw(struct device *dev)
1344 {
1345 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1346 	struct net_device *ndev = NULL;
1347 	int rc = 0;
1348 
1349 	IUCV_DBF_TEXT(trace, 3, __func__);
1350 	if (priv && priv->conn)
1351 		ndev = priv->conn->netdev;
1352 	if (!ndev)
1353 		goto out;
1354 	switch (priv->pm_state) {
1355 	case DEV_STATE_RUNNING:
1356 	case DEV_STATE_STARTWAIT:
1357 		rc = netiucv_open(ndev);
1358 		break;
1359 	default:
1360 		break;
1361 	}
1362 	netif_device_attach(ndev);
1363 out:
1364 	return rc;
1365 }
1366 
1367 /**
1368  * Start transmission of a packet.
1369  * Called from generic network device layer.
1370  *
1371  * @param skb Pointer to buffer containing the packet.
1372  * @param dev Pointer to interface struct.
1373  *
1374  * @return 0 if packet consumed, !0 if packet rejected.
1375  *         Note: If we return !0, then the packet is free'd by
1376  *               the generic network layer.
1377  */
1378 static int netiucv_tx(struct sk_buff *skb, struct net_device *dev)
1379 {
1380 	struct netiucv_priv *privptr = netdev_priv(dev);
1381 	int rc;
1382 
1383 	IUCV_DBF_TEXT(trace, 4, __func__);
1384 	/**
1385 	 * Some sanity checks ...
1386 	 */
1387 	if (skb == NULL) {
1388 		IUCV_DBF_TEXT(data, 2, "netiucv_tx: skb is NULL\n");
1389 		privptr->stats.tx_dropped++;
1390 		return NETDEV_TX_OK;
1391 	}
1392 	if (skb_headroom(skb) < NETIUCV_HDRLEN) {
1393 		IUCV_DBF_TEXT(data, 2,
1394 			"netiucv_tx: skb_headroom < NETIUCV_HDRLEN\n");
1395 		dev_kfree_skb(skb);
1396 		privptr->stats.tx_dropped++;
1397 		return NETDEV_TX_OK;
1398 	}
1399 
1400 	/**
1401 	 * If connection is not running, try to restart it
1402 	 * and throw away packet.
1403 	 */
1404 	if (fsm_getstate(privptr->fsm) != DEV_STATE_RUNNING) {
1405 		dev_kfree_skb(skb);
1406 		privptr->stats.tx_dropped++;
1407 		privptr->stats.tx_errors++;
1408 		privptr->stats.tx_carrier_errors++;
1409 		return NETDEV_TX_OK;
1410 	}
1411 
1412 	if (netiucv_test_and_set_busy(dev)) {
1413 		IUCV_DBF_TEXT(data, 2, "EBUSY from netiucv_tx\n");
1414 		return NETDEV_TX_BUSY;
1415 	}
1416 	dev->trans_start = jiffies;
1417 	rc = netiucv_transmit_skb(privptr->conn, skb);
1418 	netiucv_clear_busy(dev);
1419 	return rc ? NETDEV_TX_BUSY : NETDEV_TX_OK;
1420 }
1421 
1422 /**
1423  * netiucv_stats
1424  * @dev: Pointer to interface struct.
1425  *
1426  * Returns interface statistics of a device.
1427  *
1428  * Returns pointer to stats struct of this interface.
1429  */
1430 static struct net_device_stats *netiucv_stats (struct net_device * dev)
1431 {
1432 	struct netiucv_priv *priv = netdev_priv(dev);
1433 
1434 	IUCV_DBF_TEXT(trace, 5, __func__);
1435 	return &priv->stats;
1436 }
1437 
1438 /**
1439  * netiucv_change_mtu
1440  * @dev: Pointer to interface struct.
1441  * @new_mtu: The new MTU to use for this interface.
1442  *
1443  * Sets MTU of an interface.
1444  *
1445  * Returns 0 on success, -EINVAL if MTU is out of valid range.
1446  *         (valid range is 576 .. NETIUCV_MTU_MAX).
1447  */
1448 static int netiucv_change_mtu(struct net_device * dev, int new_mtu)
1449 {
1450 	IUCV_DBF_TEXT(trace, 3, __func__);
1451 	if (new_mtu < 576 || new_mtu > NETIUCV_MTU_MAX) {
1452 		IUCV_DBF_TEXT(setup, 2, "given MTU out of valid range\n");
1453 		return -EINVAL;
1454 	}
1455 	dev->mtu = new_mtu;
1456 	return 0;
1457 }
1458 
1459 /*
1460  * attributes in sysfs
1461  */
1462 
1463 static ssize_t user_show(struct device *dev, struct device_attribute *attr,
1464 			 char *buf)
1465 {
1466 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1467 
1468 	IUCV_DBF_TEXT(trace, 5, __func__);
1469 	return sprintf(buf, "%s\n", netiucv_printuser(priv->conn));
1470 }
1471 
1472 static int netiucv_check_user(const char *buf, size_t count, char *username,
1473 			      char *userdata)
1474 {
1475 	const char *p;
1476 	int i;
1477 
1478 	p = strchr(buf, '.');
1479 	if ((p && ((count > 26) ||
1480 		   ((p - buf) > 8) ||
1481 		   (buf + count - p > 18))) ||
1482 	    (!p && (count > 9))) {
1483 		IUCV_DBF_TEXT(setup, 2, "conn_write: too long\n");
1484 		return -EINVAL;
1485 	}
1486 
1487 	for (i = 0, p = buf; i < 8 && *p && *p != '.'; i++, p++) {
1488 		if (isalnum(*p) || *p == '$') {
1489 			username[i] = toupper(*p);
1490 			continue;
1491 		}
1492 		if (*p == '\n')
1493 			/* trailing lf, grr */
1494 			break;
1495 		IUCV_DBF_TEXT_(setup, 2,
1496 			       "conn_write: invalid character %02x\n", *p);
1497 		return -EINVAL;
1498 	}
1499 	while (i < 8)
1500 		username[i++] = ' ';
1501 	username[8] = '\0';
1502 
1503 	if (*p == '.') {
1504 		p++;
1505 		for (i = 0; i < 16 && *p; i++, p++) {
1506 			if (*p == '\n')
1507 				break;
1508 			userdata[i] = toupper(*p);
1509 		}
1510 		while (i > 0 && i < 16)
1511 			userdata[i++] = ' ';
1512 	} else
1513 		memcpy(userdata, iucvMagic_ascii, 16);
1514 	userdata[16] = '\0';
1515 	ASCEBC(userdata, 16);
1516 
1517 	return 0;
1518 }
1519 
1520 static ssize_t user_write(struct device *dev, struct device_attribute *attr,
1521 			  const char *buf, size_t count)
1522 {
1523 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1524 	struct net_device *ndev = priv->conn->netdev;
1525 	char	username[9];
1526 	char	userdata[17];
1527 	int	rc;
1528 	struct iucv_connection *cp;
1529 
1530 	IUCV_DBF_TEXT(trace, 3, __func__);
1531 	rc = netiucv_check_user(buf, count, username, userdata);
1532 	if (rc)
1533 		return rc;
1534 
1535 	if (memcmp(username, priv->conn->userid, 9) &&
1536 	    (ndev->flags & (IFF_UP | IFF_RUNNING))) {
1537 		/* username changed while the interface is active. */
1538 		IUCV_DBF_TEXT(setup, 2, "user_write: device active\n");
1539 		return -EPERM;
1540 	}
1541 	read_lock_bh(&iucv_connection_rwlock);
1542 	list_for_each_entry(cp, &iucv_connection_list, list) {
1543 		if (!strncmp(username, cp->userid, 9) &&
1544 		   !strncmp(userdata, cp->userdata, 17) && cp->netdev != ndev) {
1545 			read_unlock_bh(&iucv_connection_rwlock);
1546 			IUCV_DBF_TEXT_(setup, 2, "user_write: Connection to %s "
1547 				"already exists\n", netiucv_printuser(cp));
1548 			return -EEXIST;
1549 		}
1550 	}
1551 	read_unlock_bh(&iucv_connection_rwlock);
1552 	memcpy(priv->conn->userid, username, 9);
1553 	memcpy(priv->conn->userdata, userdata, 17);
1554 	return count;
1555 }
1556 
1557 static DEVICE_ATTR(user, 0644, user_show, user_write);
1558 
1559 static ssize_t buffer_show (struct device *dev, struct device_attribute *attr,
1560 			    char *buf)
1561 {
1562 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1563 
1564 	IUCV_DBF_TEXT(trace, 5, __func__);
1565 	return sprintf(buf, "%d\n", priv->conn->max_buffsize);
1566 }
1567 
1568 static ssize_t buffer_write (struct device *dev, struct device_attribute *attr,
1569 			     const char *buf, size_t count)
1570 {
1571 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1572 	struct net_device *ndev = priv->conn->netdev;
1573 	char         *e;
1574 	int          bs1;
1575 
1576 	IUCV_DBF_TEXT(trace, 3, __func__);
1577 	if (count >= 39)
1578 		return -EINVAL;
1579 
1580 	bs1 = simple_strtoul(buf, &e, 0);
1581 
1582 	if (e && (!isspace(*e))) {
1583 		IUCV_DBF_TEXT_(setup, 2, "buffer_write: invalid char %02x\n",
1584 			*e);
1585 		return -EINVAL;
1586 	}
1587 	if (bs1 > NETIUCV_BUFSIZE_MAX) {
1588 		IUCV_DBF_TEXT_(setup, 2,
1589 			"buffer_write: buffer size %d too large\n",
1590 			bs1);
1591 		return -EINVAL;
1592 	}
1593 	if ((ndev->flags & IFF_RUNNING) &&
1594 	    (bs1 < (ndev->mtu + NETIUCV_HDRLEN + 2))) {
1595 		IUCV_DBF_TEXT_(setup, 2,
1596 			"buffer_write: buffer size %d too small\n",
1597 			bs1);
1598 		return -EINVAL;
1599 	}
1600 	if (bs1 < (576 + NETIUCV_HDRLEN + NETIUCV_HDRLEN)) {
1601 		IUCV_DBF_TEXT_(setup, 2,
1602 			"buffer_write: buffer size %d too small\n",
1603 			bs1);
1604 		return -EINVAL;
1605 	}
1606 
1607 	priv->conn->max_buffsize = bs1;
1608 	if (!(ndev->flags & IFF_RUNNING))
1609 		ndev->mtu = bs1 - NETIUCV_HDRLEN - NETIUCV_HDRLEN;
1610 
1611 	return count;
1612 
1613 }
1614 
1615 static DEVICE_ATTR(buffer, 0644, buffer_show, buffer_write);
1616 
1617 static ssize_t dev_fsm_show (struct device *dev, struct device_attribute *attr,
1618 			     char *buf)
1619 {
1620 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1621 
1622 	IUCV_DBF_TEXT(trace, 5, __func__);
1623 	return sprintf(buf, "%s\n", fsm_getstate_str(priv->fsm));
1624 }
1625 
1626 static DEVICE_ATTR(device_fsm_state, 0444, dev_fsm_show, NULL);
1627 
1628 static ssize_t conn_fsm_show (struct device *dev,
1629 			      struct device_attribute *attr, char *buf)
1630 {
1631 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1632 
1633 	IUCV_DBF_TEXT(trace, 5, __func__);
1634 	return sprintf(buf, "%s\n", fsm_getstate_str(priv->conn->fsm));
1635 }
1636 
1637 static DEVICE_ATTR(connection_fsm_state, 0444, conn_fsm_show, NULL);
1638 
1639 static ssize_t maxmulti_show (struct device *dev,
1640 			      struct device_attribute *attr, char *buf)
1641 {
1642 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1643 
1644 	IUCV_DBF_TEXT(trace, 5, __func__);
1645 	return sprintf(buf, "%ld\n", priv->conn->prof.maxmulti);
1646 }
1647 
1648 static ssize_t maxmulti_write (struct device *dev,
1649 			       struct device_attribute *attr,
1650 			       const char *buf, size_t count)
1651 {
1652 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1653 
1654 	IUCV_DBF_TEXT(trace, 4, __func__);
1655 	priv->conn->prof.maxmulti = 0;
1656 	return count;
1657 }
1658 
1659 static DEVICE_ATTR(max_tx_buffer_used, 0644, maxmulti_show, maxmulti_write);
1660 
1661 static ssize_t maxcq_show (struct device *dev, struct device_attribute *attr,
1662 			   char *buf)
1663 {
1664 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1665 
1666 	IUCV_DBF_TEXT(trace, 5, __func__);
1667 	return sprintf(buf, "%ld\n", priv->conn->prof.maxcqueue);
1668 }
1669 
1670 static ssize_t maxcq_write (struct device *dev, struct device_attribute *attr,
1671 			    const char *buf, size_t count)
1672 {
1673 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1674 
1675 	IUCV_DBF_TEXT(trace, 4, __func__);
1676 	priv->conn->prof.maxcqueue = 0;
1677 	return count;
1678 }
1679 
1680 static DEVICE_ATTR(max_chained_skbs, 0644, maxcq_show, maxcq_write);
1681 
1682 static ssize_t sdoio_show (struct device *dev, struct device_attribute *attr,
1683 			   char *buf)
1684 {
1685 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1686 
1687 	IUCV_DBF_TEXT(trace, 5, __func__);
1688 	return sprintf(buf, "%ld\n", priv->conn->prof.doios_single);
1689 }
1690 
1691 static ssize_t sdoio_write (struct device *dev, struct device_attribute *attr,
1692 			    const char *buf, size_t count)
1693 {
1694 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1695 
1696 	IUCV_DBF_TEXT(trace, 4, __func__);
1697 	priv->conn->prof.doios_single = 0;
1698 	return count;
1699 }
1700 
1701 static DEVICE_ATTR(tx_single_write_ops, 0644, sdoio_show, sdoio_write);
1702 
1703 static ssize_t mdoio_show (struct device *dev, struct device_attribute *attr,
1704 			   char *buf)
1705 {
1706 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1707 
1708 	IUCV_DBF_TEXT(trace, 5, __func__);
1709 	return sprintf(buf, "%ld\n", priv->conn->prof.doios_multi);
1710 }
1711 
1712 static ssize_t mdoio_write (struct device *dev, struct device_attribute *attr,
1713 			    const char *buf, size_t count)
1714 {
1715 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1716 
1717 	IUCV_DBF_TEXT(trace, 5, __func__);
1718 	priv->conn->prof.doios_multi = 0;
1719 	return count;
1720 }
1721 
1722 static DEVICE_ATTR(tx_multi_write_ops, 0644, mdoio_show, mdoio_write);
1723 
1724 static ssize_t txlen_show (struct device *dev, struct device_attribute *attr,
1725 			   char *buf)
1726 {
1727 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1728 
1729 	IUCV_DBF_TEXT(trace, 5, __func__);
1730 	return sprintf(buf, "%ld\n", priv->conn->prof.txlen);
1731 }
1732 
1733 static ssize_t txlen_write (struct device *dev, struct device_attribute *attr,
1734 			    const char *buf, size_t count)
1735 {
1736 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1737 
1738 	IUCV_DBF_TEXT(trace, 4, __func__);
1739 	priv->conn->prof.txlen = 0;
1740 	return count;
1741 }
1742 
1743 static DEVICE_ATTR(netto_bytes, 0644, txlen_show, txlen_write);
1744 
1745 static ssize_t txtime_show (struct device *dev, struct device_attribute *attr,
1746 			    char *buf)
1747 {
1748 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1749 
1750 	IUCV_DBF_TEXT(trace, 5, __func__);
1751 	return sprintf(buf, "%ld\n", priv->conn->prof.tx_time);
1752 }
1753 
1754 static ssize_t txtime_write (struct device *dev, struct device_attribute *attr,
1755 			     const char *buf, size_t count)
1756 {
1757 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1758 
1759 	IUCV_DBF_TEXT(trace, 4, __func__);
1760 	priv->conn->prof.tx_time = 0;
1761 	return count;
1762 }
1763 
1764 static DEVICE_ATTR(max_tx_io_time, 0644, txtime_show, txtime_write);
1765 
1766 static ssize_t txpend_show (struct device *dev, struct device_attribute *attr,
1767 			    char *buf)
1768 {
1769 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1770 
1771 	IUCV_DBF_TEXT(trace, 5, __func__);
1772 	return sprintf(buf, "%ld\n", priv->conn->prof.tx_pending);
1773 }
1774 
1775 static ssize_t txpend_write (struct device *dev, struct device_attribute *attr,
1776 			     const char *buf, size_t count)
1777 {
1778 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1779 
1780 	IUCV_DBF_TEXT(trace, 4, __func__);
1781 	priv->conn->prof.tx_pending = 0;
1782 	return count;
1783 }
1784 
1785 static DEVICE_ATTR(tx_pending, 0644, txpend_show, txpend_write);
1786 
1787 static ssize_t txmpnd_show (struct device *dev, struct device_attribute *attr,
1788 			    char *buf)
1789 {
1790 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1791 
1792 	IUCV_DBF_TEXT(trace, 5, __func__);
1793 	return sprintf(buf, "%ld\n", priv->conn->prof.tx_max_pending);
1794 }
1795 
1796 static ssize_t txmpnd_write (struct device *dev, struct device_attribute *attr,
1797 			     const char *buf, size_t count)
1798 {
1799 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1800 
1801 	IUCV_DBF_TEXT(trace, 4, __func__);
1802 	priv->conn->prof.tx_max_pending = 0;
1803 	return count;
1804 }
1805 
1806 static DEVICE_ATTR(tx_max_pending, 0644, txmpnd_show, txmpnd_write);
1807 
1808 static struct attribute *netiucv_attrs[] = {
1809 	&dev_attr_buffer.attr,
1810 	&dev_attr_user.attr,
1811 	NULL,
1812 };
1813 
1814 static struct attribute_group netiucv_attr_group = {
1815 	.attrs = netiucv_attrs,
1816 };
1817 
1818 static struct attribute *netiucv_stat_attrs[] = {
1819 	&dev_attr_device_fsm_state.attr,
1820 	&dev_attr_connection_fsm_state.attr,
1821 	&dev_attr_max_tx_buffer_used.attr,
1822 	&dev_attr_max_chained_skbs.attr,
1823 	&dev_attr_tx_single_write_ops.attr,
1824 	&dev_attr_tx_multi_write_ops.attr,
1825 	&dev_attr_netto_bytes.attr,
1826 	&dev_attr_max_tx_io_time.attr,
1827 	&dev_attr_tx_pending.attr,
1828 	&dev_attr_tx_max_pending.attr,
1829 	NULL,
1830 };
1831 
1832 static struct attribute_group netiucv_stat_attr_group = {
1833 	.name  = "stats",
1834 	.attrs = netiucv_stat_attrs,
1835 };
1836 
1837 static const struct attribute_group *netiucv_attr_groups[] = {
1838 	&netiucv_stat_attr_group,
1839 	&netiucv_attr_group,
1840 	NULL,
1841 };
1842 
1843 static int netiucv_register_device(struct net_device *ndev)
1844 {
1845 	struct netiucv_priv *priv = netdev_priv(ndev);
1846 	struct device *dev = kzalloc(sizeof(struct device), GFP_KERNEL);
1847 	int ret;
1848 
1849 	IUCV_DBF_TEXT(trace, 3, __func__);
1850 
1851 	if (dev) {
1852 		dev_set_name(dev, "net%s", ndev->name);
1853 		dev->bus = &iucv_bus;
1854 		dev->parent = iucv_root;
1855 		dev->groups = netiucv_attr_groups;
1856 		/*
1857 		 * The release function could be called after the
1858 		 * module has been unloaded. It's _only_ task is to
1859 		 * free the struct. Therefore, we specify kfree()
1860 		 * directly here. (Probably a little bit obfuscating
1861 		 * but legitime ...).
1862 		 */
1863 		dev->release = (void (*)(struct device *))kfree;
1864 		dev->driver = &netiucv_driver;
1865 	} else
1866 		return -ENOMEM;
1867 
1868 	ret = device_register(dev);
1869 	if (ret) {
1870 		put_device(dev);
1871 		return ret;
1872 	}
1873 	priv->dev = dev;
1874 	dev_set_drvdata(dev, priv);
1875 	return 0;
1876 }
1877 
1878 static void netiucv_unregister_device(struct device *dev)
1879 {
1880 	IUCV_DBF_TEXT(trace, 3, __func__);
1881 	device_unregister(dev);
1882 }
1883 
1884 /**
1885  * Allocate and initialize a new connection structure.
1886  * Add it to the list of netiucv connections;
1887  */
1888 static struct iucv_connection *netiucv_new_connection(struct net_device *dev,
1889 						      char *username,
1890 						      char *userdata)
1891 {
1892 	struct iucv_connection *conn;
1893 
1894 	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1895 	if (!conn)
1896 		goto out;
1897 	skb_queue_head_init(&conn->collect_queue);
1898 	skb_queue_head_init(&conn->commit_queue);
1899 	spin_lock_init(&conn->collect_lock);
1900 	conn->max_buffsize = NETIUCV_BUFSIZE_DEFAULT;
1901 	conn->netdev = dev;
1902 
1903 	conn->rx_buff = alloc_skb(conn->max_buffsize, GFP_KERNEL | GFP_DMA);
1904 	if (!conn->rx_buff)
1905 		goto out_conn;
1906 	conn->tx_buff = alloc_skb(conn->max_buffsize, GFP_KERNEL | GFP_DMA);
1907 	if (!conn->tx_buff)
1908 		goto out_rx;
1909 	conn->fsm = init_fsm("netiucvconn", conn_state_names,
1910 			     conn_event_names, NR_CONN_STATES,
1911 			     NR_CONN_EVENTS, conn_fsm, CONN_FSM_LEN,
1912 			     GFP_KERNEL);
1913 	if (!conn->fsm)
1914 		goto out_tx;
1915 
1916 	fsm_settimer(conn->fsm, &conn->timer);
1917 	fsm_newstate(conn->fsm, CONN_STATE_INVALID);
1918 
1919 	if (userdata)
1920 		memcpy(conn->userdata, userdata, 17);
1921 	if (username) {
1922 		memcpy(conn->userid, username, 9);
1923 		fsm_newstate(conn->fsm, CONN_STATE_STOPPED);
1924 	}
1925 
1926 	write_lock_bh(&iucv_connection_rwlock);
1927 	list_add_tail(&conn->list, &iucv_connection_list);
1928 	write_unlock_bh(&iucv_connection_rwlock);
1929 	return conn;
1930 
1931 out_tx:
1932 	kfree_skb(conn->tx_buff);
1933 out_rx:
1934 	kfree_skb(conn->rx_buff);
1935 out_conn:
1936 	kfree(conn);
1937 out:
1938 	return NULL;
1939 }
1940 
1941 /**
1942  * Release a connection structure and remove it from the
1943  * list of netiucv connections.
1944  */
1945 static void netiucv_remove_connection(struct iucv_connection *conn)
1946 {
1947 
1948 	IUCV_DBF_TEXT(trace, 3, __func__);
1949 	write_lock_bh(&iucv_connection_rwlock);
1950 	list_del_init(&conn->list);
1951 	write_unlock_bh(&iucv_connection_rwlock);
1952 	fsm_deltimer(&conn->timer);
1953 	netiucv_purge_skb_queue(&conn->collect_queue);
1954 	if (conn->path) {
1955 		iucv_path_sever(conn->path, conn->userdata);
1956 		kfree(conn->path);
1957 		conn->path = NULL;
1958 	}
1959 	netiucv_purge_skb_queue(&conn->commit_queue);
1960 	kfree_fsm(conn->fsm);
1961 	kfree_skb(conn->rx_buff);
1962 	kfree_skb(conn->tx_buff);
1963 }
1964 
1965 /**
1966  * Release everything of a net device.
1967  */
1968 static void netiucv_free_netdevice(struct net_device *dev)
1969 {
1970 	struct netiucv_priv *privptr = netdev_priv(dev);
1971 
1972 	IUCV_DBF_TEXT(trace, 3, __func__);
1973 
1974 	if (!dev)
1975 		return;
1976 
1977 	if (privptr) {
1978 		if (privptr->conn)
1979 			netiucv_remove_connection(privptr->conn);
1980 		if (privptr->fsm)
1981 			kfree_fsm(privptr->fsm);
1982 		privptr->conn = NULL; privptr->fsm = NULL;
1983 		/* privptr gets freed by free_netdev() */
1984 	}
1985 	free_netdev(dev);
1986 }
1987 
1988 /**
1989  * Initialize a net device. (Called from kernel in alloc_netdev())
1990  */
1991 static const struct net_device_ops netiucv_netdev_ops = {
1992 	.ndo_open		= netiucv_open,
1993 	.ndo_stop		= netiucv_close,
1994 	.ndo_get_stats		= netiucv_stats,
1995 	.ndo_start_xmit		= netiucv_tx,
1996 	.ndo_change_mtu	   	= netiucv_change_mtu,
1997 };
1998 
1999 static void netiucv_setup_netdevice(struct net_device *dev)
2000 {
2001 	dev->mtu	         = NETIUCV_MTU_DEFAULT;
2002 	dev->destructor          = netiucv_free_netdevice;
2003 	dev->hard_header_len     = NETIUCV_HDRLEN;
2004 	dev->addr_len            = 0;
2005 	dev->type                = ARPHRD_SLIP;
2006 	dev->tx_queue_len        = NETIUCV_QUEUELEN_DEFAULT;
2007 	dev->flags	         = IFF_POINTOPOINT | IFF_NOARP;
2008 	dev->netdev_ops		 = &netiucv_netdev_ops;
2009 }
2010 
2011 /**
2012  * Allocate and initialize everything of a net device.
2013  */
2014 static struct net_device *netiucv_init_netdevice(char *username, char *userdata)
2015 {
2016 	struct netiucv_priv *privptr;
2017 	struct net_device *dev;
2018 
2019 	dev = alloc_netdev(sizeof(struct netiucv_priv), "iucv%d",
2020 			   netiucv_setup_netdevice);
2021 	if (!dev)
2022 		return NULL;
2023 	rtnl_lock();
2024 	if (dev_alloc_name(dev, dev->name) < 0)
2025 		goto out_netdev;
2026 
2027 	privptr = netdev_priv(dev);
2028 	privptr->fsm = init_fsm("netiucvdev", dev_state_names,
2029 				dev_event_names, NR_DEV_STATES, NR_DEV_EVENTS,
2030 				dev_fsm, DEV_FSM_LEN, GFP_KERNEL);
2031 	if (!privptr->fsm)
2032 		goto out_netdev;
2033 
2034 	privptr->conn = netiucv_new_connection(dev, username, userdata);
2035 	if (!privptr->conn) {
2036 		IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_new_connection\n");
2037 		goto out_fsm;
2038 	}
2039 	fsm_newstate(privptr->fsm, DEV_STATE_STOPPED);
2040 	return dev;
2041 
2042 out_fsm:
2043 	kfree_fsm(privptr->fsm);
2044 out_netdev:
2045 	rtnl_unlock();
2046 	free_netdev(dev);
2047 	return NULL;
2048 }
2049 
2050 static ssize_t conn_write(struct device_driver *drv,
2051 			  const char *buf, size_t count)
2052 {
2053 	char username[9];
2054 	char userdata[17];
2055 	int rc;
2056 	struct net_device *dev;
2057 	struct netiucv_priv *priv;
2058 	struct iucv_connection *cp;
2059 
2060 	IUCV_DBF_TEXT(trace, 3, __func__);
2061 	rc = netiucv_check_user(buf, count, username, userdata);
2062 	if (rc)
2063 		return rc;
2064 
2065 	read_lock_bh(&iucv_connection_rwlock);
2066 	list_for_each_entry(cp, &iucv_connection_list, list) {
2067 		if (!strncmp(username, cp->userid, 9) &&
2068 		    !strncmp(userdata, cp->userdata, 17)) {
2069 			read_unlock_bh(&iucv_connection_rwlock);
2070 			IUCV_DBF_TEXT_(setup, 2, "conn_write: Connection to %s "
2071 				"already exists\n", netiucv_printuser(cp));
2072 			return -EEXIST;
2073 		}
2074 	}
2075 	read_unlock_bh(&iucv_connection_rwlock);
2076 
2077 	dev = netiucv_init_netdevice(username, userdata);
2078 	if (!dev) {
2079 		IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_init_netdevice\n");
2080 		return -ENODEV;
2081 	}
2082 
2083 	rc = netiucv_register_device(dev);
2084 	if (rc) {
2085 		rtnl_unlock();
2086 		IUCV_DBF_TEXT_(setup, 2,
2087 			"ret %d from netiucv_register_device\n", rc);
2088 		goto out_free_ndev;
2089 	}
2090 
2091 	/* sysfs magic */
2092 	priv = netdev_priv(dev);
2093 	SET_NETDEV_DEV(dev, priv->dev);
2094 
2095 	rc = register_netdevice(dev);
2096 	rtnl_unlock();
2097 	if (rc)
2098 		goto out_unreg;
2099 
2100 	dev_info(priv->dev, "The IUCV interface to %s has been established "
2101 			    "successfully\n",
2102 		netiucv_printuser(priv->conn));
2103 
2104 	return count;
2105 
2106 out_unreg:
2107 	netiucv_unregister_device(priv->dev);
2108 out_free_ndev:
2109 	netiucv_free_netdevice(dev);
2110 	return rc;
2111 }
2112 
2113 static DRIVER_ATTR(connection, 0200, NULL, conn_write);
2114 
2115 static ssize_t remove_write (struct device_driver *drv,
2116 			     const char *buf, size_t count)
2117 {
2118 	struct iucv_connection *cp;
2119         struct net_device *ndev;
2120         struct netiucv_priv *priv;
2121         struct device *dev;
2122         char name[IFNAMSIZ];
2123 	const char *p;
2124         int i;
2125 
2126 	IUCV_DBF_TEXT(trace, 3, __func__);
2127 
2128         if (count >= IFNAMSIZ)
2129                 count = IFNAMSIZ - 1;
2130 
2131 	for (i = 0, p = buf; i < count && *p; i++, p++) {
2132 		if (*p == '\n' || *p == ' ')
2133                         /* trailing lf, grr */
2134                         break;
2135 		name[i] = *p;
2136         }
2137         name[i] = '\0';
2138 
2139 	read_lock_bh(&iucv_connection_rwlock);
2140 	list_for_each_entry(cp, &iucv_connection_list, list) {
2141 		ndev = cp->netdev;
2142 		priv = netdev_priv(ndev);
2143                 dev = priv->dev;
2144 		if (strncmp(name, ndev->name, count))
2145 			continue;
2146 		read_unlock_bh(&iucv_connection_rwlock);
2147                 if (ndev->flags & (IFF_UP | IFF_RUNNING)) {
2148 			dev_warn(dev, "The IUCV device is connected"
2149 				" to %s and cannot be removed\n",
2150 				priv->conn->userid);
2151 			IUCV_DBF_TEXT(data, 2, "remove_write: still active\n");
2152 			return -EPERM;
2153                 }
2154                 unregister_netdev(ndev);
2155                 netiucv_unregister_device(dev);
2156                 return count;
2157         }
2158 	read_unlock_bh(&iucv_connection_rwlock);
2159 	IUCV_DBF_TEXT(data, 2, "remove_write: unknown device\n");
2160         return -EINVAL;
2161 }
2162 
2163 static DRIVER_ATTR(remove, 0200, NULL, remove_write);
2164 
2165 static struct attribute * netiucv_drv_attrs[] = {
2166 	&driver_attr_connection.attr,
2167 	&driver_attr_remove.attr,
2168 	NULL,
2169 };
2170 
2171 static struct attribute_group netiucv_drv_attr_group = {
2172 	.attrs = netiucv_drv_attrs,
2173 };
2174 
2175 static const struct attribute_group *netiucv_drv_attr_groups[] = {
2176 	&netiucv_drv_attr_group,
2177 	NULL,
2178 };
2179 
2180 static void netiucv_banner(void)
2181 {
2182 	pr_info("driver initialized\n");
2183 }
2184 
2185 static void __exit netiucv_exit(void)
2186 {
2187 	struct iucv_connection *cp;
2188 	struct net_device *ndev;
2189 	struct netiucv_priv *priv;
2190 	struct device *dev;
2191 
2192 	IUCV_DBF_TEXT(trace, 3, __func__);
2193 	while (!list_empty(&iucv_connection_list)) {
2194 		cp = list_entry(iucv_connection_list.next,
2195 				struct iucv_connection, list);
2196 		ndev = cp->netdev;
2197 		priv = netdev_priv(ndev);
2198 		dev = priv->dev;
2199 
2200 		unregister_netdev(ndev);
2201 		netiucv_unregister_device(dev);
2202 	}
2203 
2204 	device_unregister(netiucv_dev);
2205 	driver_unregister(&netiucv_driver);
2206 	iucv_unregister(&netiucv_handler, 1);
2207 	iucv_unregister_dbf_views();
2208 
2209 	pr_info("driver unloaded\n");
2210 	return;
2211 }
2212 
2213 static int __init netiucv_init(void)
2214 {
2215 	int rc;
2216 
2217 	rc = iucv_register_dbf_views();
2218 	if (rc)
2219 		goto out;
2220 	rc = iucv_register(&netiucv_handler, 1);
2221 	if (rc)
2222 		goto out_dbf;
2223 	IUCV_DBF_TEXT(trace, 3, __func__);
2224 	netiucv_driver.groups = netiucv_drv_attr_groups;
2225 	rc = driver_register(&netiucv_driver);
2226 	if (rc) {
2227 		IUCV_DBF_TEXT_(setup, 2, "ret %d from driver_register\n", rc);
2228 		goto out_iucv;
2229 	}
2230 	/* establish dummy device */
2231 	netiucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2232 	if (!netiucv_dev) {
2233 		rc = -ENOMEM;
2234 		goto out_driver;
2235 	}
2236 	dev_set_name(netiucv_dev, "netiucv");
2237 	netiucv_dev->bus = &iucv_bus;
2238 	netiucv_dev->parent = iucv_root;
2239 	netiucv_dev->release = (void (*)(struct device *))kfree;
2240 	netiucv_dev->driver = &netiucv_driver;
2241 	rc = device_register(netiucv_dev);
2242 	if (rc) {
2243 		put_device(netiucv_dev);
2244 		goto out_driver;
2245 	}
2246 	netiucv_banner();
2247 	return rc;
2248 
2249 out_driver:
2250 	driver_unregister(&netiucv_driver);
2251 out_iucv:
2252 	iucv_unregister(&netiucv_handler, 1);
2253 out_dbf:
2254 	iucv_unregister_dbf_views();
2255 out:
2256 	return rc;
2257 }
2258 
2259 module_init(netiucv_init);
2260 module_exit(netiucv_exit);
2261 MODULE_LICENSE("GPL");
2262