xref: /openbmc/linux/drivers/s390/net/netiucv.c (revision 27e45f2e)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * IUCV network driver
4  *
5  * Copyright IBM Corp. 2001, 2009
6  *
7  * Author(s):
8  *	Original netiucv driver:
9  *		Fritz Elfert (elfert@de.ibm.com, felfert@millenux.com)
10  *	Sysfs integration and all bugs therein:
11  *		Cornelia Huck (cornelia.huck@de.ibm.com)
12  *	PM functions:
13  *		Ursula Braun (ursula.braun@de.ibm.com)
14  *
15  * Documentation used:
16  *  the source of the original IUCV driver by:
17  *    Stefan Hegewald <hegewald@de.ibm.com>
18  *    Hartmut Penner <hpenner@de.ibm.com>
19  *    Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
20  *    Martin Schwidefsky (schwidefsky@de.ibm.com)
21  *    Alan Altmark (Alan_Altmark@us.ibm.com)  Sept. 2000
22  */
23 
24 #define KMSG_COMPONENT "netiucv"
25 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
26 
27 #undef DEBUG
28 
29 #include <linux/module.h>
30 #include <linux/init.h>
31 #include <linux/kernel.h>
32 #include <linux/slab.h>
33 #include <linux/errno.h>
34 #include <linux/types.h>
35 #include <linux/interrupt.h>
36 #include <linux/timer.h>
37 #include <linux/bitops.h>
38 
39 #include <linux/signal.h>
40 #include <linux/string.h>
41 #include <linux/device.h>
42 
43 #include <linux/ip.h>
44 #include <linux/if_arp.h>
45 #include <linux/tcp.h>
46 #include <linux/skbuff.h>
47 #include <linux/ctype.h>
48 #include <net/dst.h>
49 
50 #include <asm/io.h>
51 #include <linux/uaccess.h>
52 #include <asm/ebcdic.h>
53 
54 #include <net/iucv/iucv.h>
55 #include "fsm.h"
56 
57 MODULE_AUTHOR
58     ("(C) 2001 IBM Corporation by Fritz Elfert (felfert@millenux.com)");
59 MODULE_DESCRIPTION ("Linux for S/390 IUCV network driver");
60 
61 /*
62  * Debug Facility stuff
63  */
64 #define IUCV_DBF_SETUP_NAME "iucv_setup"
65 #define IUCV_DBF_SETUP_LEN 64
66 #define IUCV_DBF_SETUP_PAGES 2
67 #define IUCV_DBF_SETUP_NR_AREAS 1
68 #define IUCV_DBF_SETUP_LEVEL 3
69 
70 #define IUCV_DBF_DATA_NAME "iucv_data"
71 #define IUCV_DBF_DATA_LEN 128
72 #define IUCV_DBF_DATA_PAGES 2
73 #define IUCV_DBF_DATA_NR_AREAS 1
74 #define IUCV_DBF_DATA_LEVEL 2
75 
76 #define IUCV_DBF_TRACE_NAME "iucv_trace"
77 #define IUCV_DBF_TRACE_LEN 16
78 #define IUCV_DBF_TRACE_PAGES 4
79 #define IUCV_DBF_TRACE_NR_AREAS 1
80 #define IUCV_DBF_TRACE_LEVEL 3
81 
82 #define IUCV_DBF_TEXT(name,level,text) \
83 	do { \
84 		debug_text_event(iucv_dbf_##name,level,text); \
85 	} while (0)
86 
87 #define IUCV_DBF_HEX(name,level,addr,len) \
88 	do { \
89 		debug_event(iucv_dbf_##name,level,(void*)(addr),len); \
90 	} while (0)
91 
92 DECLARE_PER_CPU(char[256], iucv_dbf_txt_buf);
93 
94 #define IUCV_DBF_TEXT_(name, level, text...) \
95 	do { \
96 		if (debug_level_enabled(iucv_dbf_##name, level)) { \
97 			char* __buf = get_cpu_var(iucv_dbf_txt_buf); \
98 			sprintf(__buf, text); \
99 			debug_text_event(iucv_dbf_##name, level, __buf); \
100 			put_cpu_var(iucv_dbf_txt_buf); \
101 		} \
102 	} while (0)
103 
104 #define IUCV_DBF_SPRINTF(name,level,text...) \
105 	do { \
106 		debug_sprintf_event(iucv_dbf_trace, level, ##text ); \
107 		debug_sprintf_event(iucv_dbf_trace, level, text ); \
108 	} while (0)
109 
110 /*
111  * some more debug stuff
112  */
113 #define PRINTK_HEADER " iucv: "       /* for debugging */
114 
115 static struct device_driver netiucv_driver = {
116 	.owner = THIS_MODULE,
117 	.name = "netiucv",
118 	.bus  = &iucv_bus,
119 };
120 
121 /*
122  * Per connection profiling data
123  */
124 struct connection_profile {
125 	unsigned long maxmulti;
126 	unsigned long maxcqueue;
127 	unsigned long doios_single;
128 	unsigned long doios_multi;
129 	unsigned long txlen;
130 	unsigned long tx_time;
131 	unsigned long send_stamp;
132 	unsigned long tx_pending;
133 	unsigned long tx_max_pending;
134 };
135 
136 /*
137  * Representation of one iucv connection
138  */
139 struct iucv_connection {
140 	struct list_head	  list;
141 	struct iucv_path	  *path;
142 	struct sk_buff            *rx_buff;
143 	struct sk_buff            *tx_buff;
144 	struct sk_buff_head       collect_queue;
145 	struct sk_buff_head	  commit_queue;
146 	spinlock_t                collect_lock;
147 	int                       collect_len;
148 	int                       max_buffsize;
149 	fsm_timer                 timer;
150 	fsm_instance              *fsm;
151 	struct net_device         *netdev;
152 	struct connection_profile prof;
153 	char                      userid[9];
154 	char			  userdata[17];
155 };
156 
157 /*
158  * Linked list of all connection structs.
159  */
160 static LIST_HEAD(iucv_connection_list);
161 static DEFINE_RWLOCK(iucv_connection_rwlock);
162 
163 /*
164  * Representation of event-data for the
165  * connection state machine.
166  */
167 struct iucv_event {
168 	struct iucv_connection *conn;
169 	void                   *data;
170 };
171 
172 /*
173  * Private part of the network device structure
174  */
175 struct netiucv_priv {
176 	struct net_device_stats stats;
177 	unsigned long           tbusy;
178 	fsm_instance            *fsm;
179         struct iucv_connection  *conn;
180 	struct device           *dev;
181 };
182 
183 /*
184  * Link level header for a packet.
185  */
186 struct ll_header {
187 	u16 next;
188 };
189 
190 #define NETIUCV_HDRLEN		 (sizeof(struct ll_header))
191 #define NETIUCV_BUFSIZE_MAX	 65537
192 #define NETIUCV_BUFSIZE_DEFAULT  NETIUCV_BUFSIZE_MAX
193 #define NETIUCV_MTU_MAX          (NETIUCV_BUFSIZE_MAX - NETIUCV_HDRLEN)
194 #define NETIUCV_MTU_DEFAULT      9216
195 #define NETIUCV_QUEUELEN_DEFAULT 50
196 #define NETIUCV_TIMEOUT_5SEC     5000
197 
198 /*
199  * Compatibility macros for busy handling
200  * of network devices.
201  */
202 static void netiucv_clear_busy(struct net_device *dev)
203 {
204 	struct netiucv_priv *priv = netdev_priv(dev);
205 	clear_bit(0, &priv->tbusy);
206 	netif_wake_queue(dev);
207 }
208 
209 static int netiucv_test_and_set_busy(struct net_device *dev)
210 {
211 	struct netiucv_priv *priv = netdev_priv(dev);
212 	netif_stop_queue(dev);
213 	return test_and_set_bit(0, &priv->tbusy);
214 }
215 
216 static u8 iucvMagic_ascii[16] = {
217 	0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20,
218 	0x30, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20
219 };
220 
221 static u8 iucvMagic_ebcdic[16] = {
222 	0xF0, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40,
223 	0xF0, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40
224 };
225 
226 /*
227  * Convert an iucv userId to its printable
228  * form (strip whitespace at end).
229  *
230  * @param An iucv userId
231  *
232  * @returns The printable string (static data!!)
233  */
234 static char *netiucv_printname(char *name, int len)
235 {
236 	static char tmp[17];
237 	char *p = tmp;
238 	memcpy(tmp, name, len);
239 	tmp[len] = '\0';
240 	while (*p && ((p - tmp) < len) && (!isspace(*p)))
241 		p++;
242 	*p = '\0';
243 	return tmp;
244 }
245 
246 static char *netiucv_printuser(struct iucv_connection *conn)
247 {
248 	static char tmp_uid[9];
249 	static char tmp_udat[17];
250 	static char buf[100];
251 
252 	if (memcmp(conn->userdata, iucvMagic_ebcdic, 16)) {
253 		tmp_uid[8] = '\0';
254 		tmp_udat[16] = '\0';
255 		memcpy(tmp_uid, netiucv_printname(conn->userid, 8), 8);
256 		memcpy(tmp_udat, conn->userdata, 16);
257 		EBCASC(tmp_udat, 16);
258 		memcpy(tmp_udat, netiucv_printname(tmp_udat, 16), 16);
259 		sprintf(buf, "%s.%s", tmp_uid, tmp_udat);
260 		return buf;
261 	} else
262 		return netiucv_printname(conn->userid, 8);
263 }
264 
265 /*
266  * States of the interface statemachine.
267  */
268 enum dev_states {
269 	DEV_STATE_STOPPED,
270 	DEV_STATE_STARTWAIT,
271 	DEV_STATE_STOPWAIT,
272 	DEV_STATE_RUNNING,
273 	/*
274 	 * MUST be always the last element!!
275 	 */
276 	NR_DEV_STATES
277 };
278 
279 static const char *dev_state_names[] = {
280 	"Stopped",
281 	"StartWait",
282 	"StopWait",
283 	"Running",
284 };
285 
286 /*
287  * Events of the interface statemachine.
288  */
289 enum dev_events {
290 	DEV_EVENT_START,
291 	DEV_EVENT_STOP,
292 	DEV_EVENT_CONUP,
293 	DEV_EVENT_CONDOWN,
294 	/*
295 	 * MUST be always the last element!!
296 	 */
297 	NR_DEV_EVENTS
298 };
299 
300 static const char *dev_event_names[] = {
301 	"Start",
302 	"Stop",
303 	"Connection up",
304 	"Connection down",
305 };
306 
307 /*
308  * Events of the connection statemachine
309  */
310 enum conn_events {
311 	/*
312 	 * Events, representing callbacks from
313 	 * lowlevel iucv layer)
314 	 */
315 	CONN_EVENT_CONN_REQ,
316 	CONN_EVENT_CONN_ACK,
317 	CONN_EVENT_CONN_REJ,
318 	CONN_EVENT_CONN_SUS,
319 	CONN_EVENT_CONN_RES,
320 	CONN_EVENT_RX,
321 	CONN_EVENT_TXDONE,
322 
323 	/*
324 	 * Events, representing errors return codes from
325 	 * calls to lowlevel iucv layer
326 	 */
327 
328 	/*
329 	 * Event, representing timer expiry.
330 	 */
331 	CONN_EVENT_TIMER,
332 
333 	/*
334 	 * Events, representing commands from upper levels.
335 	 */
336 	CONN_EVENT_START,
337 	CONN_EVENT_STOP,
338 
339 	/*
340 	 * MUST be always the last element!!
341 	 */
342 	NR_CONN_EVENTS,
343 };
344 
345 static const char *conn_event_names[] = {
346 	"Remote connection request",
347 	"Remote connection acknowledge",
348 	"Remote connection reject",
349 	"Connection suspended",
350 	"Connection resumed",
351 	"Data received",
352 	"Data sent",
353 
354 	"Timer",
355 
356 	"Start",
357 	"Stop",
358 };
359 
360 /*
361  * States of the connection statemachine.
362  */
363 enum conn_states {
364 	/*
365 	 * Connection not assigned to any device,
366 	 * initial state, invalid
367 	 */
368 	CONN_STATE_INVALID,
369 
370 	/*
371 	 * Userid assigned but not operating
372 	 */
373 	CONN_STATE_STOPPED,
374 
375 	/*
376 	 * Connection registered,
377 	 * no connection request sent yet,
378 	 * no connection request received
379 	 */
380 	CONN_STATE_STARTWAIT,
381 
382 	/*
383 	 * Connection registered and connection request sent,
384 	 * no acknowledge and no connection request received yet.
385 	 */
386 	CONN_STATE_SETUPWAIT,
387 
388 	/*
389 	 * Connection up and running idle
390 	 */
391 	CONN_STATE_IDLE,
392 
393 	/*
394 	 * Data sent, awaiting CONN_EVENT_TXDONE
395 	 */
396 	CONN_STATE_TX,
397 
398 	/*
399 	 * Error during registration.
400 	 */
401 	CONN_STATE_REGERR,
402 
403 	/*
404 	 * Error during registration.
405 	 */
406 	CONN_STATE_CONNERR,
407 
408 	/*
409 	 * MUST be always the last element!!
410 	 */
411 	NR_CONN_STATES,
412 };
413 
414 static const char *conn_state_names[] = {
415 	"Invalid",
416 	"Stopped",
417 	"StartWait",
418 	"SetupWait",
419 	"Idle",
420 	"TX",
421 	"Terminating",
422 	"Registration error",
423 	"Connect error",
424 };
425 
426 
427 /*
428  * Debug Facility Stuff
429  */
430 static debug_info_t *iucv_dbf_setup = NULL;
431 static debug_info_t *iucv_dbf_data = NULL;
432 static debug_info_t *iucv_dbf_trace = NULL;
433 
434 DEFINE_PER_CPU(char[256], iucv_dbf_txt_buf);
435 
436 static void iucv_unregister_dbf_views(void)
437 {
438 	debug_unregister(iucv_dbf_setup);
439 	debug_unregister(iucv_dbf_data);
440 	debug_unregister(iucv_dbf_trace);
441 }
442 static int iucv_register_dbf_views(void)
443 {
444 	iucv_dbf_setup = debug_register(IUCV_DBF_SETUP_NAME,
445 					IUCV_DBF_SETUP_PAGES,
446 					IUCV_DBF_SETUP_NR_AREAS,
447 					IUCV_DBF_SETUP_LEN);
448 	iucv_dbf_data = debug_register(IUCV_DBF_DATA_NAME,
449 				       IUCV_DBF_DATA_PAGES,
450 				       IUCV_DBF_DATA_NR_AREAS,
451 				       IUCV_DBF_DATA_LEN);
452 	iucv_dbf_trace = debug_register(IUCV_DBF_TRACE_NAME,
453 					IUCV_DBF_TRACE_PAGES,
454 					IUCV_DBF_TRACE_NR_AREAS,
455 					IUCV_DBF_TRACE_LEN);
456 
457 	if ((iucv_dbf_setup == NULL) || (iucv_dbf_data == NULL) ||
458 	    (iucv_dbf_trace == NULL)) {
459 		iucv_unregister_dbf_views();
460 		return -ENOMEM;
461 	}
462 	debug_register_view(iucv_dbf_setup, &debug_hex_ascii_view);
463 	debug_set_level(iucv_dbf_setup, IUCV_DBF_SETUP_LEVEL);
464 
465 	debug_register_view(iucv_dbf_data, &debug_hex_ascii_view);
466 	debug_set_level(iucv_dbf_data, IUCV_DBF_DATA_LEVEL);
467 
468 	debug_register_view(iucv_dbf_trace, &debug_hex_ascii_view);
469 	debug_set_level(iucv_dbf_trace, IUCV_DBF_TRACE_LEVEL);
470 
471 	return 0;
472 }
473 
474 /*
475  * Callback-wrappers, called from lowlevel iucv layer.
476  */
477 
478 static void netiucv_callback_rx(struct iucv_path *path,
479 				struct iucv_message *msg)
480 {
481 	struct iucv_connection *conn = path->private;
482 	struct iucv_event ev;
483 
484 	ev.conn = conn;
485 	ev.data = msg;
486 	fsm_event(conn->fsm, CONN_EVENT_RX, &ev);
487 }
488 
489 static void netiucv_callback_txdone(struct iucv_path *path,
490 				    struct iucv_message *msg)
491 {
492 	struct iucv_connection *conn = path->private;
493 	struct iucv_event ev;
494 
495 	ev.conn = conn;
496 	ev.data = msg;
497 	fsm_event(conn->fsm, CONN_EVENT_TXDONE, &ev);
498 }
499 
500 static void netiucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
501 {
502 	struct iucv_connection *conn = path->private;
503 
504 	fsm_event(conn->fsm, CONN_EVENT_CONN_ACK, conn);
505 }
506 
507 static int netiucv_callback_connreq(struct iucv_path *path, u8 *ipvmid,
508 				    u8 *ipuser)
509 {
510 	struct iucv_connection *conn = path->private;
511 	struct iucv_event ev;
512 	static char tmp_user[9];
513 	static char tmp_udat[17];
514 	int rc;
515 
516 	rc = -EINVAL;
517 	memcpy(tmp_user, netiucv_printname(ipvmid, 8), 8);
518 	memcpy(tmp_udat, ipuser, 16);
519 	EBCASC(tmp_udat, 16);
520 	read_lock_bh(&iucv_connection_rwlock);
521 	list_for_each_entry(conn, &iucv_connection_list, list) {
522 		if (strncmp(ipvmid, conn->userid, 8) ||
523 		    strncmp(ipuser, conn->userdata, 16))
524 			continue;
525 		/* Found a matching connection for this path. */
526 		conn->path = path;
527 		ev.conn = conn;
528 		ev.data = path;
529 		fsm_event(conn->fsm, CONN_EVENT_CONN_REQ, &ev);
530 		rc = 0;
531 	}
532 	IUCV_DBF_TEXT_(setup, 2, "Connection requested for %s.%s\n",
533 		       tmp_user, netiucv_printname(tmp_udat, 16));
534 	read_unlock_bh(&iucv_connection_rwlock);
535 	return rc;
536 }
537 
538 static void netiucv_callback_connrej(struct iucv_path *path, u8 *ipuser)
539 {
540 	struct iucv_connection *conn = path->private;
541 
542 	fsm_event(conn->fsm, CONN_EVENT_CONN_REJ, conn);
543 }
544 
545 static void netiucv_callback_connsusp(struct iucv_path *path, u8 *ipuser)
546 {
547 	struct iucv_connection *conn = path->private;
548 
549 	fsm_event(conn->fsm, CONN_EVENT_CONN_SUS, conn);
550 }
551 
552 static void netiucv_callback_connres(struct iucv_path *path, u8 *ipuser)
553 {
554 	struct iucv_connection *conn = path->private;
555 
556 	fsm_event(conn->fsm, CONN_EVENT_CONN_RES, conn);
557 }
558 
559 /*
560  * NOP action for statemachines
561  */
562 static void netiucv_action_nop(fsm_instance *fi, int event, void *arg)
563 {
564 }
565 
566 /*
567  * Actions of the connection statemachine
568  */
569 
570 /*
571  * netiucv_unpack_skb
572  * @conn: The connection where this skb has been received.
573  * @pskb: The received skb.
574  *
575  * Unpack a just received skb and hand it over to upper layers.
576  * Helper function for conn_action_rx.
577  */
578 static void netiucv_unpack_skb(struct iucv_connection *conn,
579 			       struct sk_buff *pskb)
580 {
581 	struct net_device     *dev = conn->netdev;
582 	struct netiucv_priv   *privptr = netdev_priv(dev);
583 	u16 offset = 0;
584 
585 	skb_put(pskb, NETIUCV_HDRLEN);
586 	pskb->dev = dev;
587 	pskb->ip_summed = CHECKSUM_NONE;
588 	pskb->protocol = cpu_to_be16(ETH_P_IP);
589 
590 	while (1) {
591 		struct sk_buff *skb;
592 		struct ll_header *header = (struct ll_header *) pskb->data;
593 
594 		if (!header->next)
595 			break;
596 
597 		skb_pull(pskb, NETIUCV_HDRLEN);
598 		header->next -= offset;
599 		offset += header->next;
600 		header->next -= NETIUCV_HDRLEN;
601 		if (skb_tailroom(pskb) < header->next) {
602 			IUCV_DBF_TEXT_(data, 2, "Illegal next field: %d > %d\n",
603 				header->next, skb_tailroom(pskb));
604 			return;
605 		}
606 		skb_put(pskb, header->next);
607 		skb_reset_mac_header(pskb);
608 		skb = dev_alloc_skb(pskb->len);
609 		if (!skb) {
610 			IUCV_DBF_TEXT(data, 2,
611 				"Out of memory in netiucv_unpack_skb\n");
612 			privptr->stats.rx_dropped++;
613 			return;
614 		}
615 		skb_copy_from_linear_data(pskb, skb_put(skb, pskb->len),
616 					  pskb->len);
617 		skb_reset_mac_header(skb);
618 		skb->dev = pskb->dev;
619 		skb->protocol = pskb->protocol;
620 		pskb->ip_summed = CHECKSUM_UNNECESSARY;
621 		privptr->stats.rx_packets++;
622 		privptr->stats.rx_bytes += skb->len;
623 		netif_rx(skb);
624 		skb_pull(pskb, header->next);
625 		skb_put(pskb, NETIUCV_HDRLEN);
626 	}
627 }
628 
629 static void conn_action_rx(fsm_instance *fi, int event, void *arg)
630 {
631 	struct iucv_event *ev = arg;
632 	struct iucv_connection *conn = ev->conn;
633 	struct iucv_message *msg = ev->data;
634 	struct netiucv_priv *privptr = netdev_priv(conn->netdev);
635 	int rc;
636 
637 	IUCV_DBF_TEXT(trace, 4, __func__);
638 
639 	if (!conn->netdev) {
640 		iucv_message_reject(conn->path, msg);
641 		IUCV_DBF_TEXT(data, 2,
642 			      "Received data for unlinked connection\n");
643 		return;
644 	}
645 	if (msg->length > conn->max_buffsize) {
646 		iucv_message_reject(conn->path, msg);
647 		privptr->stats.rx_dropped++;
648 		IUCV_DBF_TEXT_(data, 2, "msglen %d > max_buffsize %d\n",
649 			       msg->length, conn->max_buffsize);
650 		return;
651 	}
652 	conn->rx_buff->data = conn->rx_buff->head;
653 	skb_reset_tail_pointer(conn->rx_buff);
654 	conn->rx_buff->len = 0;
655 	rc = iucv_message_receive(conn->path, msg, 0, conn->rx_buff->data,
656 				  msg->length, NULL);
657 	if (rc || msg->length < 5) {
658 		privptr->stats.rx_errors++;
659 		IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_receive\n", rc);
660 		return;
661 	}
662 	netiucv_unpack_skb(conn, conn->rx_buff);
663 }
664 
665 static void conn_action_txdone(fsm_instance *fi, int event, void *arg)
666 {
667 	struct iucv_event *ev = arg;
668 	struct iucv_connection *conn = ev->conn;
669 	struct iucv_message *msg = ev->data;
670 	struct iucv_message txmsg;
671 	struct netiucv_priv *privptr = NULL;
672 	u32 single_flag = msg->tag;
673 	u32 txbytes = 0;
674 	u32 txpackets = 0;
675 	u32 stat_maxcq = 0;
676 	struct sk_buff *skb;
677 	unsigned long saveflags;
678 	struct ll_header header;
679 	int rc;
680 
681 	IUCV_DBF_TEXT(trace, 4, __func__);
682 
683 	if (!conn || !conn->netdev) {
684 		IUCV_DBF_TEXT(data, 2,
685 			      "Send confirmation for unlinked connection\n");
686 		return;
687 	}
688 	privptr = netdev_priv(conn->netdev);
689 	conn->prof.tx_pending--;
690 	if (single_flag) {
691 		if ((skb = skb_dequeue(&conn->commit_queue))) {
692 			refcount_dec(&skb->users);
693 			if (privptr) {
694 				privptr->stats.tx_packets++;
695 				privptr->stats.tx_bytes +=
696 					(skb->len - NETIUCV_HDRLEN
697 						  - NETIUCV_HDRLEN);
698 			}
699 			dev_kfree_skb_any(skb);
700 		}
701 	}
702 	conn->tx_buff->data = conn->tx_buff->head;
703 	skb_reset_tail_pointer(conn->tx_buff);
704 	conn->tx_buff->len = 0;
705 	spin_lock_irqsave(&conn->collect_lock, saveflags);
706 	while ((skb = skb_dequeue(&conn->collect_queue))) {
707 		header.next = conn->tx_buff->len + skb->len + NETIUCV_HDRLEN;
708 		skb_put_data(conn->tx_buff, &header, NETIUCV_HDRLEN);
709 		skb_copy_from_linear_data(skb,
710 					  skb_put(conn->tx_buff, skb->len),
711 					  skb->len);
712 		txbytes += skb->len;
713 		txpackets++;
714 		stat_maxcq++;
715 		refcount_dec(&skb->users);
716 		dev_kfree_skb_any(skb);
717 	}
718 	if (conn->collect_len > conn->prof.maxmulti)
719 		conn->prof.maxmulti = conn->collect_len;
720 	conn->collect_len = 0;
721 	spin_unlock_irqrestore(&conn->collect_lock, saveflags);
722 	if (conn->tx_buff->len == 0) {
723 		fsm_newstate(fi, CONN_STATE_IDLE);
724 		return;
725 	}
726 
727 	header.next = 0;
728 	skb_put_data(conn->tx_buff, &header, NETIUCV_HDRLEN);
729 	conn->prof.send_stamp = jiffies;
730 	txmsg.class = 0;
731 	txmsg.tag = 0;
732 	rc = iucv_message_send(conn->path, &txmsg, 0, 0,
733 			       conn->tx_buff->data, conn->tx_buff->len);
734 	conn->prof.doios_multi++;
735 	conn->prof.txlen += conn->tx_buff->len;
736 	conn->prof.tx_pending++;
737 	if (conn->prof.tx_pending > conn->prof.tx_max_pending)
738 		conn->prof.tx_max_pending = conn->prof.tx_pending;
739 	if (rc) {
740 		conn->prof.tx_pending--;
741 		fsm_newstate(fi, CONN_STATE_IDLE);
742 		if (privptr)
743 			privptr->stats.tx_errors += txpackets;
744 		IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_send\n", rc);
745 	} else {
746 		if (privptr) {
747 			privptr->stats.tx_packets += txpackets;
748 			privptr->stats.tx_bytes += txbytes;
749 		}
750 		if (stat_maxcq > conn->prof.maxcqueue)
751 			conn->prof.maxcqueue = stat_maxcq;
752 	}
753 }
754 
755 static struct iucv_handler netiucv_handler = {
756 	.path_pending	  = netiucv_callback_connreq,
757 	.path_complete	  = netiucv_callback_connack,
758 	.path_severed	  = netiucv_callback_connrej,
759 	.path_quiesced	  = netiucv_callback_connsusp,
760 	.path_resumed	  = netiucv_callback_connres,
761 	.message_pending  = netiucv_callback_rx,
762 	.message_complete = netiucv_callback_txdone,
763 };
764 
765 static void conn_action_connaccept(fsm_instance *fi, int event, void *arg)
766 {
767 	struct iucv_event *ev = arg;
768 	struct iucv_connection *conn = ev->conn;
769 	struct iucv_path *path = ev->data;
770 	struct net_device *netdev = conn->netdev;
771 	struct netiucv_priv *privptr = netdev_priv(netdev);
772 	int rc;
773 
774 	IUCV_DBF_TEXT(trace, 3, __func__);
775 
776 	conn->path = path;
777 	path->msglim = NETIUCV_QUEUELEN_DEFAULT;
778 	path->flags = 0;
779 	rc = iucv_path_accept(path, &netiucv_handler, conn->userdata , conn);
780 	if (rc) {
781 		IUCV_DBF_TEXT_(setup, 2, "rc %d from iucv_accept", rc);
782 		return;
783 	}
784 	fsm_newstate(fi, CONN_STATE_IDLE);
785 	netdev->tx_queue_len = conn->path->msglim;
786 	fsm_event(privptr->fsm, DEV_EVENT_CONUP, netdev);
787 }
788 
789 static void conn_action_connreject(fsm_instance *fi, int event, void *arg)
790 {
791 	struct iucv_event *ev = arg;
792 	struct iucv_path *path = ev->data;
793 
794 	IUCV_DBF_TEXT(trace, 3, __func__);
795 	iucv_path_sever(path, NULL);
796 }
797 
798 static void conn_action_connack(fsm_instance *fi, int event, void *arg)
799 {
800 	struct iucv_connection *conn = arg;
801 	struct net_device *netdev = conn->netdev;
802 	struct netiucv_priv *privptr = netdev_priv(netdev);
803 
804 	IUCV_DBF_TEXT(trace, 3, __func__);
805 	fsm_deltimer(&conn->timer);
806 	fsm_newstate(fi, CONN_STATE_IDLE);
807 	netdev->tx_queue_len = conn->path->msglim;
808 	fsm_event(privptr->fsm, DEV_EVENT_CONUP, netdev);
809 }
810 
811 static void conn_action_conntimsev(fsm_instance *fi, int event, void *arg)
812 {
813 	struct iucv_connection *conn = arg;
814 
815 	IUCV_DBF_TEXT(trace, 3, __func__);
816 	fsm_deltimer(&conn->timer);
817 	iucv_path_sever(conn->path, conn->userdata);
818 	fsm_newstate(fi, CONN_STATE_STARTWAIT);
819 }
820 
821 static void conn_action_connsever(fsm_instance *fi, int event, void *arg)
822 {
823 	struct iucv_connection *conn = arg;
824 	struct net_device *netdev = conn->netdev;
825 	struct netiucv_priv *privptr = netdev_priv(netdev);
826 
827 	IUCV_DBF_TEXT(trace, 3, __func__);
828 
829 	fsm_deltimer(&conn->timer);
830 	iucv_path_sever(conn->path, conn->userdata);
831 	dev_info(privptr->dev, "The peer z/VM guest %s has closed the "
832 			       "connection\n", netiucv_printuser(conn));
833 	IUCV_DBF_TEXT(data, 2,
834 		      "conn_action_connsever: Remote dropped connection\n");
835 	fsm_newstate(fi, CONN_STATE_STARTWAIT);
836 	fsm_event(privptr->fsm, DEV_EVENT_CONDOWN, netdev);
837 }
838 
839 static void conn_action_start(fsm_instance *fi, int event, void *arg)
840 {
841 	struct iucv_connection *conn = arg;
842 	struct net_device *netdev = conn->netdev;
843 	struct netiucv_priv *privptr = netdev_priv(netdev);
844 	int rc;
845 
846 	IUCV_DBF_TEXT(trace, 3, __func__);
847 
848 	fsm_newstate(fi, CONN_STATE_STARTWAIT);
849 
850 	/*
851 	 * We must set the state before calling iucv_connect because the
852 	 * callback handler could be called at any point after the connection
853 	 * request is sent
854 	 */
855 
856 	fsm_newstate(fi, CONN_STATE_SETUPWAIT);
857 	conn->path = iucv_path_alloc(NETIUCV_QUEUELEN_DEFAULT, 0, GFP_KERNEL);
858 	IUCV_DBF_TEXT_(setup, 2, "%s: connecting to %s ...\n",
859 		netdev->name, netiucv_printuser(conn));
860 
861 	rc = iucv_path_connect(conn->path, &netiucv_handler, conn->userid,
862 			       NULL, conn->userdata, conn);
863 	switch (rc) {
864 	case 0:
865 		netdev->tx_queue_len = conn->path->msglim;
866 		fsm_addtimer(&conn->timer, NETIUCV_TIMEOUT_5SEC,
867 			     CONN_EVENT_TIMER, conn);
868 		return;
869 	case 11:
870 		dev_warn(privptr->dev,
871 			"The IUCV device failed to connect to z/VM guest %s\n",
872 			netiucv_printname(conn->userid, 8));
873 		fsm_newstate(fi, CONN_STATE_STARTWAIT);
874 		break;
875 	case 12:
876 		dev_warn(privptr->dev,
877 			"The IUCV device failed to connect to the peer on z/VM"
878 			" guest %s\n", netiucv_printname(conn->userid, 8));
879 		fsm_newstate(fi, CONN_STATE_STARTWAIT);
880 		break;
881 	case 13:
882 		dev_err(privptr->dev,
883 			"Connecting the IUCV device would exceed the maximum"
884 			" number of IUCV connections\n");
885 		fsm_newstate(fi, CONN_STATE_CONNERR);
886 		break;
887 	case 14:
888 		dev_err(privptr->dev,
889 			"z/VM guest %s has too many IUCV connections"
890 			" to connect with the IUCV device\n",
891 			netiucv_printname(conn->userid, 8));
892 		fsm_newstate(fi, CONN_STATE_CONNERR);
893 		break;
894 	case 15:
895 		dev_err(privptr->dev,
896 			"The IUCV device cannot connect to a z/VM guest with no"
897 			" IUCV authorization\n");
898 		fsm_newstate(fi, CONN_STATE_CONNERR);
899 		break;
900 	default:
901 		dev_err(privptr->dev,
902 			"Connecting the IUCV device failed with error %d\n",
903 			rc);
904 		fsm_newstate(fi, CONN_STATE_CONNERR);
905 		break;
906 	}
907 	IUCV_DBF_TEXT_(setup, 5, "iucv_connect rc is %d\n", rc);
908 	kfree(conn->path);
909 	conn->path = NULL;
910 }
911 
912 static void netiucv_purge_skb_queue(struct sk_buff_head *q)
913 {
914 	struct sk_buff *skb;
915 
916 	while ((skb = skb_dequeue(q))) {
917 		refcount_dec(&skb->users);
918 		dev_kfree_skb_any(skb);
919 	}
920 }
921 
922 static void conn_action_stop(fsm_instance *fi, int event, void *arg)
923 {
924 	struct iucv_event *ev = arg;
925 	struct iucv_connection *conn = ev->conn;
926 	struct net_device *netdev = conn->netdev;
927 	struct netiucv_priv *privptr = netdev_priv(netdev);
928 
929 	IUCV_DBF_TEXT(trace, 3, __func__);
930 
931 	fsm_deltimer(&conn->timer);
932 	fsm_newstate(fi, CONN_STATE_STOPPED);
933 	netiucv_purge_skb_queue(&conn->collect_queue);
934 	if (conn->path) {
935 		IUCV_DBF_TEXT(trace, 5, "calling iucv_path_sever\n");
936 		iucv_path_sever(conn->path, conn->userdata);
937 		kfree(conn->path);
938 		conn->path = NULL;
939 	}
940 	netiucv_purge_skb_queue(&conn->commit_queue);
941 	fsm_event(privptr->fsm, DEV_EVENT_CONDOWN, netdev);
942 }
943 
944 static void conn_action_inval(fsm_instance *fi, int event, void *arg)
945 {
946 	struct iucv_connection *conn = arg;
947 	struct net_device *netdev = conn->netdev;
948 
949 	IUCV_DBF_TEXT_(data, 2, "%s('%s'): conn_action_inval called\n",
950 		netdev->name, conn->userid);
951 }
952 
953 static const fsm_node conn_fsm[] = {
954 	{ CONN_STATE_INVALID,   CONN_EVENT_START,    conn_action_inval      },
955 	{ CONN_STATE_STOPPED,   CONN_EVENT_START,    conn_action_start      },
956 
957 	{ CONN_STATE_STOPPED,   CONN_EVENT_STOP,     conn_action_stop       },
958 	{ CONN_STATE_STARTWAIT, CONN_EVENT_STOP,     conn_action_stop       },
959 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_STOP,     conn_action_stop       },
960 	{ CONN_STATE_IDLE,      CONN_EVENT_STOP,     conn_action_stop       },
961 	{ CONN_STATE_TX,        CONN_EVENT_STOP,     conn_action_stop       },
962 	{ CONN_STATE_REGERR,    CONN_EVENT_STOP,     conn_action_stop       },
963 	{ CONN_STATE_CONNERR,   CONN_EVENT_STOP,     conn_action_stop       },
964 
965 	{ CONN_STATE_STOPPED,   CONN_EVENT_CONN_REQ, conn_action_connreject },
966         { CONN_STATE_STARTWAIT, CONN_EVENT_CONN_REQ, conn_action_connaccept },
967 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_REQ, conn_action_connaccept },
968 	{ CONN_STATE_IDLE,      CONN_EVENT_CONN_REQ, conn_action_connreject },
969 	{ CONN_STATE_TX,        CONN_EVENT_CONN_REQ, conn_action_connreject },
970 
971 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_ACK, conn_action_connack    },
972 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_TIMER,    conn_action_conntimsev },
973 
974 	{ CONN_STATE_SETUPWAIT, CONN_EVENT_CONN_REJ, conn_action_connsever  },
975 	{ CONN_STATE_IDLE,      CONN_EVENT_CONN_REJ, conn_action_connsever  },
976 	{ CONN_STATE_TX,        CONN_EVENT_CONN_REJ, conn_action_connsever  },
977 
978 	{ CONN_STATE_IDLE,      CONN_EVENT_RX,       conn_action_rx         },
979 	{ CONN_STATE_TX,        CONN_EVENT_RX,       conn_action_rx         },
980 
981 	{ CONN_STATE_TX,        CONN_EVENT_TXDONE,   conn_action_txdone     },
982 	{ CONN_STATE_IDLE,      CONN_EVENT_TXDONE,   conn_action_txdone     },
983 };
984 
985 static const int CONN_FSM_LEN = sizeof(conn_fsm) / sizeof(fsm_node);
986 
987 
988 /*
989  * Actions for interface - statemachine.
990  */
991 
992 /*
993  * dev_action_start
994  * @fi: An instance of an interface statemachine.
995  * @event: The event, just happened.
996  * @arg: Generic pointer, casted from struct net_device * upon call.
997  *
998  * Startup connection by sending CONN_EVENT_START to it.
999  */
1000 static void dev_action_start(fsm_instance *fi, int event, void *arg)
1001 {
1002 	struct net_device   *dev = arg;
1003 	struct netiucv_priv *privptr = netdev_priv(dev);
1004 
1005 	IUCV_DBF_TEXT(trace, 3, __func__);
1006 
1007 	fsm_newstate(fi, DEV_STATE_STARTWAIT);
1008 	fsm_event(privptr->conn->fsm, CONN_EVENT_START, privptr->conn);
1009 }
1010 
1011 /*
1012  * Shutdown connection by sending CONN_EVENT_STOP to it.
1013  *
1014  * @param fi    An instance of an interface statemachine.
1015  * @param event The event, just happened.
1016  * @param arg   Generic pointer, casted from struct net_device * upon call.
1017  */
1018 static void
1019 dev_action_stop(fsm_instance *fi, int event, void *arg)
1020 {
1021 	struct net_device   *dev = arg;
1022 	struct netiucv_priv *privptr = netdev_priv(dev);
1023 	struct iucv_event   ev;
1024 
1025 	IUCV_DBF_TEXT(trace, 3, __func__);
1026 
1027 	ev.conn = privptr->conn;
1028 
1029 	fsm_newstate(fi, DEV_STATE_STOPWAIT);
1030 	fsm_event(privptr->conn->fsm, CONN_EVENT_STOP, &ev);
1031 }
1032 
1033 /*
1034  * Called from connection statemachine
1035  * when a connection is up and running.
1036  *
1037  * @param fi    An instance of an interface statemachine.
1038  * @param event The event, just happened.
1039  * @param arg   Generic pointer, casted from struct net_device * upon call.
1040  */
1041 static void
1042 dev_action_connup(fsm_instance *fi, int event, void *arg)
1043 {
1044 	struct net_device   *dev = arg;
1045 	struct netiucv_priv *privptr = netdev_priv(dev);
1046 
1047 	IUCV_DBF_TEXT(trace, 3, __func__);
1048 
1049 	switch (fsm_getstate(fi)) {
1050 		case DEV_STATE_STARTWAIT:
1051 			fsm_newstate(fi, DEV_STATE_RUNNING);
1052 			dev_info(privptr->dev,
1053 				"The IUCV device has been connected"
1054 				" successfully to %s\n",
1055 				netiucv_printuser(privptr->conn));
1056 			IUCV_DBF_TEXT(setup, 3,
1057 				"connection is up and running\n");
1058 			break;
1059 		case DEV_STATE_STOPWAIT:
1060 			IUCV_DBF_TEXT(data, 2,
1061 				"dev_action_connup: in DEV_STATE_STOPWAIT\n");
1062 			break;
1063 	}
1064 }
1065 
1066 /*
1067  * Called from connection statemachine
1068  * when a connection has been shutdown.
1069  *
1070  * @param fi    An instance of an interface statemachine.
1071  * @param event The event, just happened.
1072  * @param arg   Generic pointer, casted from struct net_device * upon call.
1073  */
1074 static void
1075 dev_action_conndown(fsm_instance *fi, int event, void *arg)
1076 {
1077 	IUCV_DBF_TEXT(trace, 3, __func__);
1078 
1079 	switch (fsm_getstate(fi)) {
1080 		case DEV_STATE_RUNNING:
1081 			fsm_newstate(fi, DEV_STATE_STARTWAIT);
1082 			break;
1083 		case DEV_STATE_STOPWAIT:
1084 			fsm_newstate(fi, DEV_STATE_STOPPED);
1085 			IUCV_DBF_TEXT(setup, 3, "connection is down\n");
1086 			break;
1087 	}
1088 }
1089 
1090 static const fsm_node dev_fsm[] = {
1091 	{ DEV_STATE_STOPPED,    DEV_EVENT_START,   dev_action_start    },
1092 
1093 	{ DEV_STATE_STOPWAIT,   DEV_EVENT_START,   dev_action_start    },
1094 	{ DEV_STATE_STOPWAIT,   DEV_EVENT_CONDOWN, dev_action_conndown },
1095 
1096 	{ DEV_STATE_STARTWAIT,  DEV_EVENT_STOP,    dev_action_stop     },
1097 	{ DEV_STATE_STARTWAIT,  DEV_EVENT_CONUP,   dev_action_connup   },
1098 
1099 	{ DEV_STATE_RUNNING,    DEV_EVENT_STOP,    dev_action_stop     },
1100 	{ DEV_STATE_RUNNING,    DEV_EVENT_CONDOWN, dev_action_conndown },
1101 	{ DEV_STATE_RUNNING,    DEV_EVENT_CONUP,   netiucv_action_nop  },
1102 };
1103 
1104 static const int DEV_FSM_LEN = sizeof(dev_fsm) / sizeof(fsm_node);
1105 
1106 /*
1107  * Transmit a packet.
1108  * This is a helper function for netiucv_tx().
1109  *
1110  * @param conn Connection to be used for sending.
1111  * @param skb Pointer to struct sk_buff of packet to send.
1112  *            The linklevel header has already been set up
1113  *            by netiucv_tx().
1114  *
1115  * @return 0 on success, -ERRNO on failure. (Never fails.)
1116  */
1117 static int netiucv_transmit_skb(struct iucv_connection *conn,
1118 				struct sk_buff *skb)
1119 {
1120 	struct iucv_message msg;
1121 	unsigned long saveflags;
1122 	struct ll_header header;
1123 	int rc;
1124 
1125 	if (fsm_getstate(conn->fsm) != CONN_STATE_IDLE) {
1126 		int l = skb->len + NETIUCV_HDRLEN;
1127 
1128 		spin_lock_irqsave(&conn->collect_lock, saveflags);
1129 		if (conn->collect_len + l >
1130 		    (conn->max_buffsize - NETIUCV_HDRLEN)) {
1131 			rc = -EBUSY;
1132 			IUCV_DBF_TEXT(data, 2,
1133 				      "EBUSY from netiucv_transmit_skb\n");
1134 		} else {
1135 			refcount_inc(&skb->users);
1136 			skb_queue_tail(&conn->collect_queue, skb);
1137 			conn->collect_len += l;
1138 			rc = 0;
1139 		}
1140 		spin_unlock_irqrestore(&conn->collect_lock, saveflags);
1141 	} else {
1142 		struct sk_buff *nskb = skb;
1143 		/*
1144 		 * Copy the skb to a new allocated skb in lowmem only if the
1145 		 * data is located above 2G in memory or tailroom is < 2.
1146 		 */
1147 		unsigned long hi = ((unsigned long)(skb_tail_pointer(skb) +
1148 				    NETIUCV_HDRLEN)) >> 31;
1149 		int copied = 0;
1150 		if (hi || (skb_tailroom(skb) < 2)) {
1151 			nskb = alloc_skb(skb->len + NETIUCV_HDRLEN +
1152 					 NETIUCV_HDRLEN, GFP_ATOMIC | GFP_DMA);
1153 			if (!nskb) {
1154 				IUCV_DBF_TEXT(data, 2, "alloc_skb failed\n");
1155 				rc = -ENOMEM;
1156 				return rc;
1157 			} else {
1158 				skb_reserve(nskb, NETIUCV_HDRLEN);
1159 				skb_put_data(nskb, skb->data, skb->len);
1160 			}
1161 			copied = 1;
1162 		}
1163 		/*
1164 		 * skb now is below 2G and has enough room. Add headers.
1165 		 */
1166 		header.next = nskb->len + NETIUCV_HDRLEN;
1167 		memcpy(skb_push(nskb, NETIUCV_HDRLEN), &header, NETIUCV_HDRLEN);
1168 		header.next = 0;
1169 		skb_put_data(nskb, &header, NETIUCV_HDRLEN);
1170 
1171 		fsm_newstate(conn->fsm, CONN_STATE_TX);
1172 		conn->prof.send_stamp = jiffies;
1173 
1174 		msg.tag = 1;
1175 		msg.class = 0;
1176 		rc = iucv_message_send(conn->path, &msg, 0, 0,
1177 				       nskb->data, nskb->len);
1178 		conn->prof.doios_single++;
1179 		conn->prof.txlen += skb->len;
1180 		conn->prof.tx_pending++;
1181 		if (conn->prof.tx_pending > conn->prof.tx_max_pending)
1182 			conn->prof.tx_max_pending = conn->prof.tx_pending;
1183 		if (rc) {
1184 			struct netiucv_priv *privptr;
1185 			fsm_newstate(conn->fsm, CONN_STATE_IDLE);
1186 			conn->prof.tx_pending--;
1187 			privptr = netdev_priv(conn->netdev);
1188 			if (privptr)
1189 				privptr->stats.tx_errors++;
1190 			if (copied)
1191 				dev_kfree_skb(nskb);
1192 			else {
1193 				/*
1194 				 * Remove our headers. They get added
1195 				 * again on retransmit.
1196 				 */
1197 				skb_pull(skb, NETIUCV_HDRLEN);
1198 				skb_trim(skb, skb->len - NETIUCV_HDRLEN);
1199 			}
1200 			IUCV_DBF_TEXT_(data, 2, "rc %d from iucv_send\n", rc);
1201 		} else {
1202 			if (copied)
1203 				dev_kfree_skb(skb);
1204 			refcount_inc(&nskb->users);
1205 			skb_queue_tail(&conn->commit_queue, nskb);
1206 		}
1207 	}
1208 
1209 	return rc;
1210 }
1211 
1212 /*
1213  * Interface API for upper network layers
1214  */
1215 
1216 /*
1217  * Open an interface.
1218  * Called from generic network layer when ifconfig up is run.
1219  *
1220  * @param dev Pointer to interface struct.
1221  *
1222  * @return 0 on success, -ERRNO on failure. (Never fails.)
1223  */
1224 static int netiucv_open(struct net_device *dev)
1225 {
1226 	struct netiucv_priv *priv = netdev_priv(dev);
1227 
1228 	fsm_event(priv->fsm, DEV_EVENT_START, dev);
1229 	return 0;
1230 }
1231 
1232 /*
1233  * Close an interface.
1234  * Called from generic network layer when ifconfig down is run.
1235  *
1236  * @param dev Pointer to interface struct.
1237  *
1238  * @return 0 on success, -ERRNO on failure. (Never fails.)
1239  */
1240 static int netiucv_close(struct net_device *dev)
1241 {
1242 	struct netiucv_priv *priv = netdev_priv(dev);
1243 
1244 	fsm_event(priv->fsm, DEV_EVENT_STOP, dev);
1245 	return 0;
1246 }
1247 
1248 /*
1249  * Start transmission of a packet.
1250  * Called from generic network device layer.
1251  */
1252 static netdev_tx_t netiucv_tx(struct sk_buff *skb, struct net_device *dev)
1253 {
1254 	struct netiucv_priv *privptr = netdev_priv(dev);
1255 	int rc;
1256 
1257 	IUCV_DBF_TEXT(trace, 4, __func__);
1258 	/*
1259 	 * Some sanity checks ...
1260 	 */
1261 	if (skb == NULL) {
1262 		IUCV_DBF_TEXT(data, 2, "netiucv_tx: skb is NULL\n");
1263 		privptr->stats.tx_dropped++;
1264 		return NETDEV_TX_OK;
1265 	}
1266 	if (skb_headroom(skb) < NETIUCV_HDRLEN) {
1267 		IUCV_DBF_TEXT(data, 2,
1268 			"netiucv_tx: skb_headroom < NETIUCV_HDRLEN\n");
1269 		dev_kfree_skb(skb);
1270 		privptr->stats.tx_dropped++;
1271 		return NETDEV_TX_OK;
1272 	}
1273 
1274 	/*
1275 	 * If connection is not running, try to restart it
1276 	 * and throw away packet.
1277 	 */
1278 	if (fsm_getstate(privptr->fsm) != DEV_STATE_RUNNING) {
1279 		dev_kfree_skb(skb);
1280 		privptr->stats.tx_dropped++;
1281 		privptr->stats.tx_errors++;
1282 		privptr->stats.tx_carrier_errors++;
1283 		return NETDEV_TX_OK;
1284 	}
1285 
1286 	if (netiucv_test_and_set_busy(dev)) {
1287 		IUCV_DBF_TEXT(data, 2, "EBUSY from netiucv_tx\n");
1288 		return NETDEV_TX_BUSY;
1289 	}
1290 	netif_trans_update(dev);
1291 	rc = netiucv_transmit_skb(privptr->conn, skb);
1292 	netiucv_clear_busy(dev);
1293 	return rc ? NETDEV_TX_BUSY : NETDEV_TX_OK;
1294 }
1295 
1296 /*
1297  * netiucv_stats
1298  * @dev: Pointer to interface struct.
1299  *
1300  * Returns interface statistics of a device.
1301  *
1302  * Returns pointer to stats struct of this interface.
1303  */
1304 static struct net_device_stats *netiucv_stats (struct net_device * dev)
1305 {
1306 	struct netiucv_priv *priv = netdev_priv(dev);
1307 
1308 	IUCV_DBF_TEXT(trace, 5, __func__);
1309 	return &priv->stats;
1310 }
1311 
1312 /*
1313  * attributes in sysfs
1314  */
1315 
1316 static ssize_t user_show(struct device *dev, struct device_attribute *attr,
1317 			 char *buf)
1318 {
1319 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1320 
1321 	IUCV_DBF_TEXT(trace, 5, __func__);
1322 	return sprintf(buf, "%s\n", netiucv_printuser(priv->conn));
1323 }
1324 
1325 static int netiucv_check_user(const char *buf, size_t count, char *username,
1326 			      char *userdata)
1327 {
1328 	const char *p;
1329 	int i;
1330 
1331 	p = strchr(buf, '.');
1332 	if ((p && ((count > 26) ||
1333 		   ((p - buf) > 8) ||
1334 		   (buf + count - p > 18))) ||
1335 	    (!p && (count > 9))) {
1336 		IUCV_DBF_TEXT(setup, 2, "conn_write: too long\n");
1337 		return -EINVAL;
1338 	}
1339 
1340 	for (i = 0, p = buf; i < 8 && *p && *p != '.'; i++, p++) {
1341 		if (isalnum(*p) || *p == '$') {
1342 			username[i] = toupper(*p);
1343 			continue;
1344 		}
1345 		if (*p == '\n')
1346 			/* trailing lf, grr */
1347 			break;
1348 		IUCV_DBF_TEXT_(setup, 2,
1349 			       "conn_write: invalid character %02x\n", *p);
1350 		return -EINVAL;
1351 	}
1352 	while (i < 8)
1353 		username[i++] = ' ';
1354 	username[8] = '\0';
1355 
1356 	if (*p == '.') {
1357 		p++;
1358 		for (i = 0; i < 16 && *p; i++, p++) {
1359 			if (*p == '\n')
1360 				break;
1361 			userdata[i] = toupper(*p);
1362 		}
1363 		while (i > 0 && i < 16)
1364 			userdata[i++] = ' ';
1365 	} else
1366 		memcpy(userdata, iucvMagic_ascii, 16);
1367 	userdata[16] = '\0';
1368 	ASCEBC(userdata, 16);
1369 
1370 	return 0;
1371 }
1372 
1373 static ssize_t user_write(struct device *dev, struct device_attribute *attr,
1374 			  const char *buf, size_t count)
1375 {
1376 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1377 	struct net_device *ndev = priv->conn->netdev;
1378 	char	username[9];
1379 	char	userdata[17];
1380 	int	rc;
1381 	struct iucv_connection *cp;
1382 
1383 	IUCV_DBF_TEXT(trace, 3, __func__);
1384 	rc = netiucv_check_user(buf, count, username, userdata);
1385 	if (rc)
1386 		return rc;
1387 
1388 	if (memcmp(username, priv->conn->userid, 9) &&
1389 	    (ndev->flags & (IFF_UP | IFF_RUNNING))) {
1390 		/* username changed while the interface is active. */
1391 		IUCV_DBF_TEXT(setup, 2, "user_write: device active\n");
1392 		return -EPERM;
1393 	}
1394 	read_lock_bh(&iucv_connection_rwlock);
1395 	list_for_each_entry(cp, &iucv_connection_list, list) {
1396 		if (!strncmp(username, cp->userid, 9) &&
1397 		   !strncmp(userdata, cp->userdata, 17) && cp->netdev != ndev) {
1398 			read_unlock_bh(&iucv_connection_rwlock);
1399 			IUCV_DBF_TEXT_(setup, 2, "user_write: Connection to %s "
1400 				"already exists\n", netiucv_printuser(cp));
1401 			return -EEXIST;
1402 		}
1403 	}
1404 	read_unlock_bh(&iucv_connection_rwlock);
1405 	memcpy(priv->conn->userid, username, 9);
1406 	memcpy(priv->conn->userdata, userdata, 17);
1407 	return count;
1408 }
1409 
1410 static DEVICE_ATTR(user, 0644, user_show, user_write);
1411 
1412 static ssize_t buffer_show (struct device *dev, struct device_attribute *attr,
1413 			    char *buf)
1414 {
1415 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1416 
1417 	IUCV_DBF_TEXT(trace, 5, __func__);
1418 	return sprintf(buf, "%d\n", priv->conn->max_buffsize);
1419 }
1420 
1421 static ssize_t buffer_write (struct device *dev, struct device_attribute *attr,
1422 			     const char *buf, size_t count)
1423 {
1424 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1425 	struct net_device *ndev = priv->conn->netdev;
1426 	unsigned int bs1;
1427 	int rc;
1428 
1429 	IUCV_DBF_TEXT(trace, 3, __func__);
1430 	if (count >= 39)
1431 		return -EINVAL;
1432 
1433 	rc = kstrtouint(buf, 0, &bs1);
1434 
1435 	if (rc == -EINVAL) {
1436 		IUCV_DBF_TEXT_(setup, 2, "buffer_write: invalid char %s\n",
1437 			buf);
1438 		return -EINVAL;
1439 	}
1440 	if ((rc == -ERANGE) || (bs1 > NETIUCV_BUFSIZE_MAX)) {
1441 		IUCV_DBF_TEXT_(setup, 2,
1442 			"buffer_write: buffer size %d too large\n",
1443 			bs1);
1444 		return -EINVAL;
1445 	}
1446 	if ((ndev->flags & IFF_RUNNING) &&
1447 	    (bs1 < (ndev->mtu + NETIUCV_HDRLEN + 2))) {
1448 		IUCV_DBF_TEXT_(setup, 2,
1449 			"buffer_write: buffer size %d too small\n",
1450 			bs1);
1451 		return -EINVAL;
1452 	}
1453 	if (bs1 < (576 + NETIUCV_HDRLEN + NETIUCV_HDRLEN)) {
1454 		IUCV_DBF_TEXT_(setup, 2,
1455 			"buffer_write: buffer size %d too small\n",
1456 			bs1);
1457 		return -EINVAL;
1458 	}
1459 
1460 	priv->conn->max_buffsize = bs1;
1461 	if (!(ndev->flags & IFF_RUNNING))
1462 		ndev->mtu = bs1 - NETIUCV_HDRLEN - NETIUCV_HDRLEN;
1463 
1464 	return count;
1465 
1466 }
1467 
1468 static DEVICE_ATTR(buffer, 0644, buffer_show, buffer_write);
1469 
1470 static ssize_t dev_fsm_show (struct device *dev, struct device_attribute *attr,
1471 			     char *buf)
1472 {
1473 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1474 
1475 	IUCV_DBF_TEXT(trace, 5, __func__);
1476 	return sprintf(buf, "%s\n", fsm_getstate_str(priv->fsm));
1477 }
1478 
1479 static DEVICE_ATTR(device_fsm_state, 0444, dev_fsm_show, NULL);
1480 
1481 static ssize_t conn_fsm_show (struct device *dev,
1482 			      struct device_attribute *attr, char *buf)
1483 {
1484 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1485 
1486 	IUCV_DBF_TEXT(trace, 5, __func__);
1487 	return sprintf(buf, "%s\n", fsm_getstate_str(priv->conn->fsm));
1488 }
1489 
1490 static DEVICE_ATTR(connection_fsm_state, 0444, conn_fsm_show, NULL);
1491 
1492 static ssize_t maxmulti_show (struct device *dev,
1493 			      struct device_attribute *attr, char *buf)
1494 {
1495 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1496 
1497 	IUCV_DBF_TEXT(trace, 5, __func__);
1498 	return sprintf(buf, "%ld\n", priv->conn->prof.maxmulti);
1499 }
1500 
1501 static ssize_t maxmulti_write (struct device *dev,
1502 			       struct device_attribute *attr,
1503 			       const char *buf, size_t count)
1504 {
1505 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1506 
1507 	IUCV_DBF_TEXT(trace, 4, __func__);
1508 	priv->conn->prof.maxmulti = 0;
1509 	return count;
1510 }
1511 
1512 static DEVICE_ATTR(max_tx_buffer_used, 0644, maxmulti_show, maxmulti_write);
1513 
1514 static ssize_t maxcq_show (struct device *dev, struct device_attribute *attr,
1515 			   char *buf)
1516 {
1517 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1518 
1519 	IUCV_DBF_TEXT(trace, 5, __func__);
1520 	return sprintf(buf, "%ld\n", priv->conn->prof.maxcqueue);
1521 }
1522 
1523 static ssize_t maxcq_write (struct device *dev, struct device_attribute *attr,
1524 			    const char *buf, size_t count)
1525 {
1526 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1527 
1528 	IUCV_DBF_TEXT(trace, 4, __func__);
1529 	priv->conn->prof.maxcqueue = 0;
1530 	return count;
1531 }
1532 
1533 static DEVICE_ATTR(max_chained_skbs, 0644, maxcq_show, maxcq_write);
1534 
1535 static ssize_t sdoio_show (struct device *dev, struct device_attribute *attr,
1536 			   char *buf)
1537 {
1538 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1539 
1540 	IUCV_DBF_TEXT(trace, 5, __func__);
1541 	return sprintf(buf, "%ld\n", priv->conn->prof.doios_single);
1542 }
1543 
1544 static ssize_t sdoio_write (struct device *dev, struct device_attribute *attr,
1545 			    const char *buf, size_t count)
1546 {
1547 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1548 
1549 	IUCV_DBF_TEXT(trace, 4, __func__);
1550 	priv->conn->prof.doios_single = 0;
1551 	return count;
1552 }
1553 
1554 static DEVICE_ATTR(tx_single_write_ops, 0644, sdoio_show, sdoio_write);
1555 
1556 static ssize_t mdoio_show (struct device *dev, struct device_attribute *attr,
1557 			   char *buf)
1558 {
1559 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1560 
1561 	IUCV_DBF_TEXT(trace, 5, __func__);
1562 	return sprintf(buf, "%ld\n", priv->conn->prof.doios_multi);
1563 }
1564 
1565 static ssize_t mdoio_write (struct device *dev, struct device_attribute *attr,
1566 			    const char *buf, size_t count)
1567 {
1568 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1569 
1570 	IUCV_DBF_TEXT(trace, 5, __func__);
1571 	priv->conn->prof.doios_multi = 0;
1572 	return count;
1573 }
1574 
1575 static DEVICE_ATTR(tx_multi_write_ops, 0644, mdoio_show, mdoio_write);
1576 
1577 static ssize_t txlen_show (struct device *dev, struct device_attribute *attr,
1578 			   char *buf)
1579 {
1580 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1581 
1582 	IUCV_DBF_TEXT(trace, 5, __func__);
1583 	return sprintf(buf, "%ld\n", priv->conn->prof.txlen);
1584 }
1585 
1586 static ssize_t txlen_write (struct device *dev, struct device_attribute *attr,
1587 			    const char *buf, size_t count)
1588 {
1589 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1590 
1591 	IUCV_DBF_TEXT(trace, 4, __func__);
1592 	priv->conn->prof.txlen = 0;
1593 	return count;
1594 }
1595 
1596 static DEVICE_ATTR(netto_bytes, 0644, txlen_show, txlen_write);
1597 
1598 static ssize_t txtime_show (struct device *dev, struct device_attribute *attr,
1599 			    char *buf)
1600 {
1601 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1602 
1603 	IUCV_DBF_TEXT(trace, 5, __func__);
1604 	return sprintf(buf, "%ld\n", priv->conn->prof.tx_time);
1605 }
1606 
1607 static ssize_t txtime_write (struct device *dev, struct device_attribute *attr,
1608 			     const char *buf, size_t count)
1609 {
1610 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1611 
1612 	IUCV_DBF_TEXT(trace, 4, __func__);
1613 	priv->conn->prof.tx_time = 0;
1614 	return count;
1615 }
1616 
1617 static DEVICE_ATTR(max_tx_io_time, 0644, txtime_show, txtime_write);
1618 
1619 static ssize_t txpend_show (struct device *dev, struct device_attribute *attr,
1620 			    char *buf)
1621 {
1622 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1623 
1624 	IUCV_DBF_TEXT(trace, 5, __func__);
1625 	return sprintf(buf, "%ld\n", priv->conn->prof.tx_pending);
1626 }
1627 
1628 static ssize_t txpend_write (struct device *dev, struct device_attribute *attr,
1629 			     const char *buf, size_t count)
1630 {
1631 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1632 
1633 	IUCV_DBF_TEXT(trace, 4, __func__);
1634 	priv->conn->prof.tx_pending = 0;
1635 	return count;
1636 }
1637 
1638 static DEVICE_ATTR(tx_pending, 0644, txpend_show, txpend_write);
1639 
1640 static ssize_t txmpnd_show (struct device *dev, struct device_attribute *attr,
1641 			    char *buf)
1642 {
1643 	struct netiucv_priv *priv = dev_get_drvdata(dev);
1644 
1645 	IUCV_DBF_TEXT(trace, 5, __func__);
1646 	return sprintf(buf, "%ld\n", priv->conn->prof.tx_max_pending);
1647 }
1648 
1649 static ssize_t txmpnd_write (struct device *dev, 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.tx_max_pending = 0;
1656 	return count;
1657 }
1658 
1659 static DEVICE_ATTR(tx_max_pending, 0644, txmpnd_show, txmpnd_write);
1660 
1661 static struct attribute *netiucv_attrs[] = {
1662 	&dev_attr_buffer.attr,
1663 	&dev_attr_user.attr,
1664 	NULL,
1665 };
1666 
1667 static struct attribute_group netiucv_attr_group = {
1668 	.attrs = netiucv_attrs,
1669 };
1670 
1671 static struct attribute *netiucv_stat_attrs[] = {
1672 	&dev_attr_device_fsm_state.attr,
1673 	&dev_attr_connection_fsm_state.attr,
1674 	&dev_attr_max_tx_buffer_used.attr,
1675 	&dev_attr_max_chained_skbs.attr,
1676 	&dev_attr_tx_single_write_ops.attr,
1677 	&dev_attr_tx_multi_write_ops.attr,
1678 	&dev_attr_netto_bytes.attr,
1679 	&dev_attr_max_tx_io_time.attr,
1680 	&dev_attr_tx_pending.attr,
1681 	&dev_attr_tx_max_pending.attr,
1682 	NULL,
1683 };
1684 
1685 static struct attribute_group netiucv_stat_attr_group = {
1686 	.name  = "stats",
1687 	.attrs = netiucv_stat_attrs,
1688 };
1689 
1690 static const struct attribute_group *netiucv_attr_groups[] = {
1691 	&netiucv_stat_attr_group,
1692 	&netiucv_attr_group,
1693 	NULL,
1694 };
1695 
1696 static int netiucv_register_device(struct net_device *ndev)
1697 {
1698 	struct netiucv_priv *priv = netdev_priv(ndev);
1699 	struct device *dev = kzalloc(sizeof(struct device), GFP_KERNEL);
1700 	int ret;
1701 
1702 	IUCV_DBF_TEXT(trace, 3, __func__);
1703 
1704 	if (dev) {
1705 		dev_set_name(dev, "net%s", ndev->name);
1706 		dev->bus = &iucv_bus;
1707 		dev->parent = iucv_root;
1708 		dev->groups = netiucv_attr_groups;
1709 		/*
1710 		 * The release function could be called after the
1711 		 * module has been unloaded. It's _only_ task is to
1712 		 * free the struct. Therefore, we specify kfree()
1713 		 * directly here. (Probably a little bit obfuscating
1714 		 * but legitime ...).
1715 		 */
1716 		dev->release = (void (*)(struct device *))kfree;
1717 		dev->driver = &netiucv_driver;
1718 	} else
1719 		return -ENOMEM;
1720 
1721 	ret = device_register(dev);
1722 	if (ret) {
1723 		put_device(dev);
1724 		return ret;
1725 	}
1726 	priv->dev = dev;
1727 	dev_set_drvdata(dev, priv);
1728 	return 0;
1729 }
1730 
1731 static void netiucv_unregister_device(struct device *dev)
1732 {
1733 	IUCV_DBF_TEXT(trace, 3, __func__);
1734 	device_unregister(dev);
1735 }
1736 
1737 /*
1738  * Allocate and initialize a new connection structure.
1739  * Add it to the list of netiucv connections;
1740  */
1741 static struct iucv_connection *netiucv_new_connection(struct net_device *dev,
1742 						      char *username,
1743 						      char *userdata)
1744 {
1745 	struct iucv_connection *conn;
1746 
1747 	conn = kzalloc(sizeof(*conn), GFP_KERNEL);
1748 	if (!conn)
1749 		goto out;
1750 	skb_queue_head_init(&conn->collect_queue);
1751 	skb_queue_head_init(&conn->commit_queue);
1752 	spin_lock_init(&conn->collect_lock);
1753 	conn->max_buffsize = NETIUCV_BUFSIZE_DEFAULT;
1754 	conn->netdev = dev;
1755 
1756 	conn->rx_buff = alloc_skb(conn->max_buffsize, GFP_KERNEL | GFP_DMA);
1757 	if (!conn->rx_buff)
1758 		goto out_conn;
1759 	conn->tx_buff = alloc_skb(conn->max_buffsize, GFP_KERNEL | GFP_DMA);
1760 	if (!conn->tx_buff)
1761 		goto out_rx;
1762 	conn->fsm = init_fsm("netiucvconn", conn_state_names,
1763 			     conn_event_names, NR_CONN_STATES,
1764 			     NR_CONN_EVENTS, conn_fsm, CONN_FSM_LEN,
1765 			     GFP_KERNEL);
1766 	if (!conn->fsm)
1767 		goto out_tx;
1768 
1769 	fsm_settimer(conn->fsm, &conn->timer);
1770 	fsm_newstate(conn->fsm, CONN_STATE_INVALID);
1771 
1772 	if (userdata)
1773 		memcpy(conn->userdata, userdata, 17);
1774 	if (username) {
1775 		memcpy(conn->userid, username, 9);
1776 		fsm_newstate(conn->fsm, CONN_STATE_STOPPED);
1777 	}
1778 
1779 	write_lock_bh(&iucv_connection_rwlock);
1780 	list_add_tail(&conn->list, &iucv_connection_list);
1781 	write_unlock_bh(&iucv_connection_rwlock);
1782 	return conn;
1783 
1784 out_tx:
1785 	kfree_skb(conn->tx_buff);
1786 out_rx:
1787 	kfree_skb(conn->rx_buff);
1788 out_conn:
1789 	kfree(conn);
1790 out:
1791 	return NULL;
1792 }
1793 
1794 /*
1795  * Release a connection structure and remove it from the
1796  * list of netiucv connections.
1797  */
1798 static void netiucv_remove_connection(struct iucv_connection *conn)
1799 {
1800 
1801 	IUCV_DBF_TEXT(trace, 3, __func__);
1802 	write_lock_bh(&iucv_connection_rwlock);
1803 	list_del_init(&conn->list);
1804 	write_unlock_bh(&iucv_connection_rwlock);
1805 	fsm_deltimer(&conn->timer);
1806 	netiucv_purge_skb_queue(&conn->collect_queue);
1807 	if (conn->path) {
1808 		iucv_path_sever(conn->path, conn->userdata);
1809 		kfree(conn->path);
1810 		conn->path = NULL;
1811 	}
1812 	netiucv_purge_skb_queue(&conn->commit_queue);
1813 	kfree_fsm(conn->fsm);
1814 	kfree_skb(conn->rx_buff);
1815 	kfree_skb(conn->tx_buff);
1816 }
1817 
1818 /*
1819  * Release everything of a net device.
1820  */
1821 static void netiucv_free_netdevice(struct net_device *dev)
1822 {
1823 	struct netiucv_priv *privptr = netdev_priv(dev);
1824 
1825 	IUCV_DBF_TEXT(trace, 3, __func__);
1826 
1827 	if (!dev)
1828 		return;
1829 
1830 	if (privptr) {
1831 		if (privptr->conn)
1832 			netiucv_remove_connection(privptr->conn);
1833 		if (privptr->fsm)
1834 			kfree_fsm(privptr->fsm);
1835 		privptr->conn = NULL; privptr->fsm = NULL;
1836 		/* privptr gets freed by free_netdev() */
1837 	}
1838 }
1839 
1840 /*
1841  * Initialize a net device. (Called from kernel in alloc_netdev())
1842  */
1843 static const struct net_device_ops netiucv_netdev_ops = {
1844 	.ndo_open		= netiucv_open,
1845 	.ndo_stop		= netiucv_close,
1846 	.ndo_get_stats		= netiucv_stats,
1847 	.ndo_start_xmit		= netiucv_tx,
1848 };
1849 
1850 static void netiucv_setup_netdevice(struct net_device *dev)
1851 {
1852 	dev->mtu	         = NETIUCV_MTU_DEFAULT;
1853 	dev->min_mtu		 = 576;
1854 	dev->max_mtu		 = NETIUCV_MTU_MAX;
1855 	dev->needs_free_netdev   = true;
1856 	dev->priv_destructor     = netiucv_free_netdevice;
1857 	dev->hard_header_len     = NETIUCV_HDRLEN;
1858 	dev->addr_len            = 0;
1859 	dev->type                = ARPHRD_SLIP;
1860 	dev->tx_queue_len        = NETIUCV_QUEUELEN_DEFAULT;
1861 	dev->flags	         = IFF_POINTOPOINT | IFF_NOARP;
1862 	dev->netdev_ops		 = &netiucv_netdev_ops;
1863 }
1864 
1865 /*
1866  * Allocate and initialize everything of a net device.
1867  */
1868 static struct net_device *netiucv_init_netdevice(char *username, char *userdata)
1869 {
1870 	struct netiucv_priv *privptr;
1871 	struct net_device *dev;
1872 
1873 	dev = alloc_netdev(sizeof(struct netiucv_priv), "iucv%d",
1874 			   NET_NAME_UNKNOWN, netiucv_setup_netdevice);
1875 	if (!dev)
1876 		return NULL;
1877 	rtnl_lock();
1878 	if (dev_alloc_name(dev, dev->name) < 0)
1879 		goto out_netdev;
1880 
1881 	privptr = netdev_priv(dev);
1882 	privptr->fsm = init_fsm("netiucvdev", dev_state_names,
1883 				dev_event_names, NR_DEV_STATES, NR_DEV_EVENTS,
1884 				dev_fsm, DEV_FSM_LEN, GFP_KERNEL);
1885 	if (!privptr->fsm)
1886 		goto out_netdev;
1887 
1888 	privptr->conn = netiucv_new_connection(dev, username, userdata);
1889 	if (!privptr->conn) {
1890 		IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_new_connection\n");
1891 		goto out_fsm;
1892 	}
1893 	fsm_newstate(privptr->fsm, DEV_STATE_STOPPED);
1894 	return dev;
1895 
1896 out_fsm:
1897 	kfree_fsm(privptr->fsm);
1898 out_netdev:
1899 	rtnl_unlock();
1900 	free_netdev(dev);
1901 	return NULL;
1902 }
1903 
1904 static ssize_t connection_store(struct device_driver *drv, const char *buf,
1905 				size_t count)
1906 {
1907 	char username[9];
1908 	char userdata[17];
1909 	int rc;
1910 	struct net_device *dev;
1911 	struct netiucv_priv *priv;
1912 	struct iucv_connection *cp;
1913 
1914 	IUCV_DBF_TEXT(trace, 3, __func__);
1915 	rc = netiucv_check_user(buf, count, username, userdata);
1916 	if (rc)
1917 		return rc;
1918 
1919 	read_lock_bh(&iucv_connection_rwlock);
1920 	list_for_each_entry(cp, &iucv_connection_list, list) {
1921 		if (!strncmp(username, cp->userid, 9) &&
1922 		    !strncmp(userdata, cp->userdata, 17)) {
1923 			read_unlock_bh(&iucv_connection_rwlock);
1924 			IUCV_DBF_TEXT_(setup, 2, "conn_write: Connection to %s "
1925 				"already exists\n", netiucv_printuser(cp));
1926 			return -EEXIST;
1927 		}
1928 	}
1929 	read_unlock_bh(&iucv_connection_rwlock);
1930 
1931 	dev = netiucv_init_netdevice(username, userdata);
1932 	if (!dev) {
1933 		IUCV_DBF_TEXT(setup, 2, "NULL from netiucv_init_netdevice\n");
1934 		return -ENODEV;
1935 	}
1936 
1937 	rc = netiucv_register_device(dev);
1938 	if (rc) {
1939 		rtnl_unlock();
1940 		IUCV_DBF_TEXT_(setup, 2,
1941 			"ret %d from netiucv_register_device\n", rc);
1942 		goto out_free_ndev;
1943 	}
1944 
1945 	/* sysfs magic */
1946 	priv = netdev_priv(dev);
1947 	SET_NETDEV_DEV(dev, priv->dev);
1948 
1949 	rc = register_netdevice(dev);
1950 	rtnl_unlock();
1951 	if (rc)
1952 		goto out_unreg;
1953 
1954 	dev_info(priv->dev, "The IUCV interface to %s has been established "
1955 			    "successfully\n",
1956 		netiucv_printuser(priv->conn));
1957 
1958 	return count;
1959 
1960 out_unreg:
1961 	netiucv_unregister_device(priv->dev);
1962 out_free_ndev:
1963 	netiucv_free_netdevice(dev);
1964 	return rc;
1965 }
1966 static DRIVER_ATTR_WO(connection);
1967 
1968 static ssize_t remove_store(struct device_driver *drv, const char *buf,
1969 			    size_t count)
1970 {
1971 	struct iucv_connection *cp;
1972         struct net_device *ndev;
1973         struct netiucv_priv *priv;
1974         struct device *dev;
1975         char name[IFNAMSIZ];
1976 	const char *p;
1977         int i;
1978 
1979 	IUCV_DBF_TEXT(trace, 3, __func__);
1980 
1981         if (count >= IFNAMSIZ)
1982                 count = IFNAMSIZ - 1;
1983 
1984 	for (i = 0, p = buf; i < count && *p; i++, p++) {
1985 		if (*p == '\n' || *p == ' ')
1986                         /* trailing lf, grr */
1987                         break;
1988 		name[i] = *p;
1989         }
1990         name[i] = '\0';
1991 
1992 	read_lock_bh(&iucv_connection_rwlock);
1993 	list_for_each_entry(cp, &iucv_connection_list, list) {
1994 		ndev = cp->netdev;
1995 		priv = netdev_priv(ndev);
1996                 dev = priv->dev;
1997 		if (strncmp(name, ndev->name, count))
1998 			continue;
1999 		read_unlock_bh(&iucv_connection_rwlock);
2000                 if (ndev->flags & (IFF_UP | IFF_RUNNING)) {
2001 			dev_warn(dev, "The IUCV device is connected"
2002 				" to %s and cannot be removed\n",
2003 				priv->conn->userid);
2004 			IUCV_DBF_TEXT(data, 2, "remove_write: still active\n");
2005 			return -EPERM;
2006                 }
2007                 unregister_netdev(ndev);
2008                 netiucv_unregister_device(dev);
2009                 return count;
2010         }
2011 	read_unlock_bh(&iucv_connection_rwlock);
2012 	IUCV_DBF_TEXT(data, 2, "remove_write: unknown device\n");
2013         return -EINVAL;
2014 }
2015 static DRIVER_ATTR_WO(remove);
2016 
2017 static struct attribute * netiucv_drv_attrs[] = {
2018 	&driver_attr_connection.attr,
2019 	&driver_attr_remove.attr,
2020 	NULL,
2021 };
2022 
2023 static struct attribute_group netiucv_drv_attr_group = {
2024 	.attrs = netiucv_drv_attrs,
2025 };
2026 
2027 static const struct attribute_group *netiucv_drv_attr_groups[] = {
2028 	&netiucv_drv_attr_group,
2029 	NULL,
2030 };
2031 
2032 static void netiucv_banner(void)
2033 {
2034 	pr_info("driver initialized\n");
2035 }
2036 
2037 static void __exit netiucv_exit(void)
2038 {
2039 	struct iucv_connection *cp;
2040 	struct net_device *ndev;
2041 	struct netiucv_priv *priv;
2042 	struct device *dev;
2043 
2044 	IUCV_DBF_TEXT(trace, 3, __func__);
2045 	while (!list_empty(&iucv_connection_list)) {
2046 		cp = list_entry(iucv_connection_list.next,
2047 				struct iucv_connection, list);
2048 		ndev = cp->netdev;
2049 		priv = netdev_priv(ndev);
2050 		dev = priv->dev;
2051 
2052 		unregister_netdev(ndev);
2053 		netiucv_unregister_device(dev);
2054 	}
2055 
2056 	driver_unregister(&netiucv_driver);
2057 	iucv_unregister(&netiucv_handler, 1);
2058 	iucv_unregister_dbf_views();
2059 
2060 	pr_info("driver unloaded\n");
2061 	return;
2062 }
2063 
2064 static int __init netiucv_init(void)
2065 {
2066 	int rc;
2067 
2068 	rc = iucv_register_dbf_views();
2069 	if (rc)
2070 		goto out;
2071 	rc = iucv_register(&netiucv_handler, 1);
2072 	if (rc)
2073 		goto out_dbf;
2074 	IUCV_DBF_TEXT(trace, 3, __func__);
2075 	netiucv_driver.groups = netiucv_drv_attr_groups;
2076 	rc = driver_register(&netiucv_driver);
2077 	if (rc) {
2078 		IUCV_DBF_TEXT_(setup, 2, "ret %d from driver_register\n", rc);
2079 		goto out_iucv;
2080 	}
2081 
2082 	netiucv_banner();
2083 	return rc;
2084 
2085 out_iucv:
2086 	iucv_unregister(&netiucv_handler, 1);
2087 out_dbf:
2088 	iucv_unregister_dbf_views();
2089 out:
2090 	return rc;
2091 }
2092 
2093 module_init(netiucv_init);
2094 module_exit(netiucv_exit);
2095 MODULE_LICENSE("GPL");
2096