xref: /openbmc/linux/net/iucv/af_iucv.c (revision 9a6b55ac)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  IUCV protocol stack for Linux on zSeries
4  *
5  *  Copyright IBM Corp. 2006, 2009
6  *
7  *  Author(s):	Jennifer Hunt <jenhunt@us.ibm.com>
8  *		Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
9  *  PM functions:
10  *		Ursula Braun <ursula.braun@de.ibm.com>
11  */
12 
13 #define KMSG_COMPONENT "af_iucv"
14 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
15 
16 #include <linux/module.h>
17 #include <linux/netdevice.h>
18 #include <linux/types.h>
19 #include <linux/list.h>
20 #include <linux/errno.h>
21 #include <linux/kernel.h>
22 #include <linux/sched/signal.h>
23 #include <linux/slab.h>
24 #include <linux/skbuff.h>
25 #include <linux/init.h>
26 #include <linux/poll.h>
27 #include <linux/security.h>
28 #include <net/sock.h>
29 #include <asm/ebcdic.h>
30 #include <asm/cpcmd.h>
31 #include <linux/kmod.h>
32 
33 #include <net/iucv/af_iucv.h>
34 
35 #define VERSION "1.2"
36 
37 static char iucv_userid[80];
38 
39 static const struct proto_ops iucv_sock_ops;
40 
41 static struct proto iucv_proto = {
42 	.name		= "AF_IUCV",
43 	.owner		= THIS_MODULE,
44 	.obj_size	= sizeof(struct iucv_sock),
45 };
46 
47 static struct iucv_interface *pr_iucv;
48 
49 /* special AF_IUCV IPRM messages */
50 static const u8 iprm_shutdown[8] =
51 	{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
52 
53 #define TRGCLS_SIZE	sizeof_field(struct iucv_message, class)
54 
55 #define __iucv_sock_wait(sk, condition, timeo, ret)			\
56 do {									\
57 	DEFINE_WAIT(__wait);						\
58 	long __timeo = timeo;						\
59 	ret = 0;							\
60 	prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE);	\
61 	while (!(condition)) {						\
62 		if (!__timeo) {						\
63 			ret = -EAGAIN;					\
64 			break;						\
65 		}							\
66 		if (signal_pending(current)) {				\
67 			ret = sock_intr_errno(__timeo);			\
68 			break;						\
69 		}							\
70 		release_sock(sk);					\
71 		__timeo = schedule_timeout(__timeo);			\
72 		lock_sock(sk);						\
73 		ret = sock_error(sk);					\
74 		if (ret)						\
75 			break;						\
76 	}								\
77 	finish_wait(sk_sleep(sk), &__wait);				\
78 } while (0)
79 
80 #define iucv_sock_wait(sk, condition, timeo)				\
81 ({									\
82 	int __ret = 0;							\
83 	if (!(condition))						\
84 		__iucv_sock_wait(sk, condition, timeo, __ret);		\
85 	__ret;								\
86 })
87 
88 static void iucv_sock_kill(struct sock *sk);
89 static void iucv_sock_close(struct sock *sk);
90 static void iucv_sever_path(struct sock *, int);
91 
92 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
93 	struct packet_type *pt, struct net_device *orig_dev);
94 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
95 		   struct sk_buff *skb, u8 flags);
96 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
97 
98 /* Call Back functions */
99 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
100 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
101 static void iucv_callback_connack(struct iucv_path *, u8 *);
102 static int iucv_callback_connreq(struct iucv_path *, u8 *, u8 *);
103 static void iucv_callback_connrej(struct iucv_path *, u8 *);
104 static void iucv_callback_shutdown(struct iucv_path *, u8 *);
105 
106 static struct iucv_sock_list iucv_sk_list = {
107 	.lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
108 	.autobind_name = ATOMIC_INIT(0)
109 };
110 
111 static struct iucv_handler af_iucv_handler = {
112 	.path_pending	  = iucv_callback_connreq,
113 	.path_complete	  = iucv_callback_connack,
114 	.path_severed	  = iucv_callback_connrej,
115 	.message_pending  = iucv_callback_rx,
116 	.message_complete = iucv_callback_txdone,
117 	.path_quiesced	  = iucv_callback_shutdown,
118 };
119 
120 static inline void high_nmcpy(unsigned char *dst, char *src)
121 {
122        memcpy(dst, src, 8);
123 }
124 
125 static inline void low_nmcpy(unsigned char *dst, char *src)
126 {
127        memcpy(&dst[8], src, 8);
128 }
129 
130 static int afiucv_pm_prepare(struct device *dev)
131 {
132 #ifdef CONFIG_PM_DEBUG
133 	printk(KERN_WARNING "afiucv_pm_prepare\n");
134 #endif
135 	return 0;
136 }
137 
138 static void afiucv_pm_complete(struct device *dev)
139 {
140 #ifdef CONFIG_PM_DEBUG
141 	printk(KERN_WARNING "afiucv_pm_complete\n");
142 #endif
143 }
144 
145 /**
146  * afiucv_pm_freeze() - Freeze PM callback
147  * @dev:	AFIUCV dummy device
148  *
149  * Sever all established IUCV communication pathes
150  */
151 static int afiucv_pm_freeze(struct device *dev)
152 {
153 	struct iucv_sock *iucv;
154 	struct sock *sk;
155 
156 #ifdef CONFIG_PM_DEBUG
157 	printk(KERN_WARNING "afiucv_pm_freeze\n");
158 #endif
159 	read_lock(&iucv_sk_list.lock);
160 	sk_for_each(sk, &iucv_sk_list.head) {
161 		iucv = iucv_sk(sk);
162 		switch (sk->sk_state) {
163 		case IUCV_DISCONN:
164 		case IUCV_CLOSING:
165 		case IUCV_CONNECTED:
166 			iucv_sever_path(sk, 0);
167 			break;
168 		case IUCV_OPEN:
169 		case IUCV_BOUND:
170 		case IUCV_LISTEN:
171 		case IUCV_CLOSED:
172 		default:
173 			break;
174 		}
175 		skb_queue_purge(&iucv->send_skb_q);
176 		skb_queue_purge(&iucv->backlog_skb_q);
177 	}
178 	read_unlock(&iucv_sk_list.lock);
179 	return 0;
180 }
181 
182 /**
183  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
184  * @dev:	AFIUCV dummy device
185  *
186  * socket clean up after freeze
187  */
188 static int afiucv_pm_restore_thaw(struct device *dev)
189 {
190 	struct sock *sk;
191 
192 #ifdef CONFIG_PM_DEBUG
193 	printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
194 #endif
195 	read_lock(&iucv_sk_list.lock);
196 	sk_for_each(sk, &iucv_sk_list.head) {
197 		switch (sk->sk_state) {
198 		case IUCV_CONNECTED:
199 			sk->sk_err = EPIPE;
200 			sk->sk_state = IUCV_DISCONN;
201 			sk->sk_state_change(sk);
202 			break;
203 		case IUCV_DISCONN:
204 		case IUCV_CLOSING:
205 		case IUCV_LISTEN:
206 		case IUCV_BOUND:
207 		case IUCV_OPEN:
208 		default:
209 			break;
210 		}
211 	}
212 	read_unlock(&iucv_sk_list.lock);
213 	return 0;
214 }
215 
216 static const struct dev_pm_ops afiucv_pm_ops = {
217 	.prepare = afiucv_pm_prepare,
218 	.complete = afiucv_pm_complete,
219 	.freeze = afiucv_pm_freeze,
220 	.thaw = afiucv_pm_restore_thaw,
221 	.restore = afiucv_pm_restore_thaw,
222 };
223 
224 static struct device_driver af_iucv_driver = {
225 	.owner = THIS_MODULE,
226 	.name = "afiucv",
227 	.bus  = NULL,
228 	.pm   = &afiucv_pm_ops,
229 };
230 
231 /* dummy device used as trigger for PM functions */
232 static struct device *af_iucv_dev;
233 
234 /**
235  * iucv_msg_length() - Returns the length of an iucv message.
236  * @msg:	Pointer to struct iucv_message, MUST NOT be NULL
237  *
238  * The function returns the length of the specified iucv message @msg of data
239  * stored in a buffer and of data stored in the parameter list (PRMDATA).
240  *
241  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
242  * data:
243  *	PRMDATA[0..6]	socket data (max 7 bytes);
244  *	PRMDATA[7]	socket data length value (len is 0xff - PRMDATA[7])
245  *
246  * The socket data length is computed by subtracting the socket data length
247  * value from 0xFF.
248  * If the socket data len is greater 7, then PRMDATA can be used for special
249  * notifications (see iucv_sock_shutdown); and further,
250  * if the socket data len is > 7, the function returns 8.
251  *
252  * Use this function to allocate socket buffers to store iucv message data.
253  */
254 static inline size_t iucv_msg_length(struct iucv_message *msg)
255 {
256 	size_t datalen;
257 
258 	if (msg->flags & IUCV_IPRMDATA) {
259 		datalen = 0xff - msg->rmmsg[7];
260 		return (datalen < 8) ? datalen : 8;
261 	}
262 	return msg->length;
263 }
264 
265 /**
266  * iucv_sock_in_state() - check for specific states
267  * @sk:		sock structure
268  * @state:	first iucv sk state
269  * @state:	second iucv sk state
270  *
271  * Returns true if the socket in either in the first or second state.
272  */
273 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
274 {
275 	return (sk->sk_state == state || sk->sk_state == state2);
276 }
277 
278 /**
279  * iucv_below_msglim() - function to check if messages can be sent
280  * @sk:		sock structure
281  *
282  * Returns true if the send queue length is lower than the message limit.
283  * Always returns true if the socket is not connected (no iucv path for
284  * checking the message limit).
285  */
286 static inline int iucv_below_msglim(struct sock *sk)
287 {
288 	struct iucv_sock *iucv = iucv_sk(sk);
289 
290 	if (sk->sk_state != IUCV_CONNECTED)
291 		return 1;
292 	if (iucv->transport == AF_IUCV_TRANS_IUCV)
293 		return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
294 	else
295 		return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
296 			(atomic_read(&iucv->pendings) <= 0));
297 }
298 
299 /**
300  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
301  */
302 static void iucv_sock_wake_msglim(struct sock *sk)
303 {
304 	struct socket_wq *wq;
305 
306 	rcu_read_lock();
307 	wq = rcu_dereference(sk->sk_wq);
308 	if (skwq_has_sleeper(wq))
309 		wake_up_interruptible_all(&wq->wait);
310 	sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
311 	rcu_read_unlock();
312 }
313 
314 /**
315  * afiucv_hs_send() - send a message through HiperSockets transport
316  */
317 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
318 		   struct sk_buff *skb, u8 flags)
319 {
320 	struct iucv_sock *iucv = iucv_sk(sock);
321 	struct af_iucv_trans_hdr *phs_hdr;
322 	struct sk_buff *nskb;
323 	int err, confirm_recv = 0;
324 
325 	phs_hdr = skb_push(skb, sizeof(*phs_hdr));
326 	memset(phs_hdr, 0, sizeof(*phs_hdr));
327 	skb_reset_network_header(skb);
328 
329 	phs_hdr->magic = ETH_P_AF_IUCV;
330 	phs_hdr->version = 1;
331 	phs_hdr->flags = flags;
332 	if (flags == AF_IUCV_FLAG_SYN)
333 		phs_hdr->window = iucv->msglimit;
334 	else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
335 		confirm_recv = atomic_read(&iucv->msg_recv);
336 		phs_hdr->window = confirm_recv;
337 		if (confirm_recv)
338 			phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
339 	}
340 	memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
341 	memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
342 	memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
343 	memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
344 	ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
345 	ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
346 	ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
347 	ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
348 	if (imsg)
349 		memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
350 
351 	skb->dev = iucv->hs_dev;
352 	if (!skb->dev) {
353 		err = -ENODEV;
354 		goto err_free;
355 	}
356 
357 	dev_hard_header(skb, skb->dev, ETH_P_AF_IUCV, NULL, NULL, skb->len);
358 
359 	if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev)) {
360 		err = -ENETDOWN;
361 		goto err_free;
362 	}
363 	if (skb->len > skb->dev->mtu) {
364 		if (sock->sk_type == SOCK_SEQPACKET) {
365 			err = -EMSGSIZE;
366 			goto err_free;
367 		}
368 		skb_trim(skb, skb->dev->mtu);
369 	}
370 	skb->protocol = cpu_to_be16(ETH_P_AF_IUCV);
371 
372 	__skb_header_release(skb);
373 	nskb = skb_clone(skb, GFP_ATOMIC);
374 	if (!nskb) {
375 		err = -ENOMEM;
376 		goto err_free;
377 	}
378 
379 	skb_queue_tail(&iucv->send_skb_q, nskb);
380 	err = dev_queue_xmit(skb);
381 	if (net_xmit_eval(err)) {
382 		skb_unlink(nskb, &iucv->send_skb_q);
383 		kfree_skb(nskb);
384 	} else {
385 		atomic_sub(confirm_recv, &iucv->msg_recv);
386 		WARN_ON(atomic_read(&iucv->msg_recv) < 0);
387 	}
388 	return net_xmit_eval(err);
389 
390 err_free:
391 	kfree_skb(skb);
392 	return err;
393 }
394 
395 static struct sock *__iucv_get_sock_by_name(char *nm)
396 {
397 	struct sock *sk;
398 
399 	sk_for_each(sk, &iucv_sk_list.head)
400 		if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
401 			return sk;
402 
403 	return NULL;
404 }
405 
406 static void iucv_sock_destruct(struct sock *sk)
407 {
408 	skb_queue_purge(&sk->sk_receive_queue);
409 	skb_queue_purge(&sk->sk_error_queue);
410 
411 	sk_mem_reclaim(sk);
412 
413 	if (!sock_flag(sk, SOCK_DEAD)) {
414 		pr_err("Attempt to release alive iucv socket %p\n", sk);
415 		return;
416 	}
417 
418 	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
419 	WARN_ON(refcount_read(&sk->sk_wmem_alloc));
420 	WARN_ON(sk->sk_wmem_queued);
421 	WARN_ON(sk->sk_forward_alloc);
422 }
423 
424 /* Cleanup Listen */
425 static void iucv_sock_cleanup_listen(struct sock *parent)
426 {
427 	struct sock *sk;
428 
429 	/* Close non-accepted connections */
430 	while ((sk = iucv_accept_dequeue(parent, NULL))) {
431 		iucv_sock_close(sk);
432 		iucv_sock_kill(sk);
433 	}
434 
435 	parent->sk_state = IUCV_CLOSED;
436 }
437 
438 /* Kill socket (only if zapped and orphaned) */
439 static void iucv_sock_kill(struct sock *sk)
440 {
441 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
442 		return;
443 
444 	iucv_sock_unlink(&iucv_sk_list, sk);
445 	sock_set_flag(sk, SOCK_DEAD);
446 	sock_put(sk);
447 }
448 
449 /* Terminate an IUCV path */
450 static void iucv_sever_path(struct sock *sk, int with_user_data)
451 {
452 	unsigned char user_data[16];
453 	struct iucv_sock *iucv = iucv_sk(sk);
454 	struct iucv_path *path = iucv->path;
455 
456 	if (iucv->path) {
457 		iucv->path = NULL;
458 		if (with_user_data) {
459 			low_nmcpy(user_data, iucv->src_name);
460 			high_nmcpy(user_data, iucv->dst_name);
461 			ASCEBC(user_data, sizeof(user_data));
462 			pr_iucv->path_sever(path, user_data);
463 		} else
464 			pr_iucv->path_sever(path, NULL);
465 		iucv_path_free(path);
466 	}
467 }
468 
469 /* Send controlling flags through an IUCV socket for HIPER transport */
470 static int iucv_send_ctrl(struct sock *sk, u8 flags)
471 {
472 	struct iucv_sock *iucv = iucv_sk(sk);
473 	int err = 0;
474 	int blen;
475 	struct sk_buff *skb;
476 	u8 shutdown = 0;
477 
478 	blen = sizeof(struct af_iucv_trans_hdr) +
479 	       LL_RESERVED_SPACE(iucv->hs_dev);
480 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
481 		/* controlling flags should be sent anyway */
482 		shutdown = sk->sk_shutdown;
483 		sk->sk_shutdown &= RCV_SHUTDOWN;
484 	}
485 	skb = sock_alloc_send_skb(sk, blen, 1, &err);
486 	if (skb) {
487 		skb_reserve(skb, blen);
488 		err = afiucv_hs_send(NULL, sk, skb, flags);
489 	}
490 	if (shutdown)
491 		sk->sk_shutdown = shutdown;
492 	return err;
493 }
494 
495 /* Close an IUCV socket */
496 static void iucv_sock_close(struct sock *sk)
497 {
498 	struct iucv_sock *iucv = iucv_sk(sk);
499 	unsigned long timeo;
500 	int err = 0;
501 
502 	lock_sock(sk);
503 
504 	switch (sk->sk_state) {
505 	case IUCV_LISTEN:
506 		iucv_sock_cleanup_listen(sk);
507 		break;
508 
509 	case IUCV_CONNECTED:
510 		if (iucv->transport == AF_IUCV_TRANS_HIPER) {
511 			err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
512 			sk->sk_state = IUCV_DISCONN;
513 			sk->sk_state_change(sk);
514 		}
515 		/* fall through */
516 
517 	case IUCV_DISCONN:
518 		sk->sk_state = IUCV_CLOSING;
519 		sk->sk_state_change(sk);
520 
521 		if (!err && !skb_queue_empty(&iucv->send_skb_q)) {
522 			if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
523 				timeo = sk->sk_lingertime;
524 			else
525 				timeo = IUCV_DISCONN_TIMEOUT;
526 			iucv_sock_wait(sk,
527 					iucv_sock_in_state(sk, IUCV_CLOSED, 0),
528 					timeo);
529 		}
530 		/* fall through */
531 
532 	case IUCV_CLOSING:
533 		sk->sk_state = IUCV_CLOSED;
534 		sk->sk_state_change(sk);
535 
536 		sk->sk_err = ECONNRESET;
537 		sk->sk_state_change(sk);
538 
539 		skb_queue_purge(&iucv->send_skb_q);
540 		skb_queue_purge(&iucv->backlog_skb_q);
541 		/* fall through */
542 
543 	default:
544 		iucv_sever_path(sk, 1);
545 	}
546 
547 	if (iucv->hs_dev) {
548 		dev_put(iucv->hs_dev);
549 		iucv->hs_dev = NULL;
550 		sk->sk_bound_dev_if = 0;
551 	}
552 
553 	/* mark socket for deletion by iucv_sock_kill() */
554 	sock_set_flag(sk, SOCK_ZAPPED);
555 
556 	release_sock(sk);
557 }
558 
559 static void iucv_sock_init(struct sock *sk, struct sock *parent)
560 {
561 	if (parent) {
562 		sk->sk_type = parent->sk_type;
563 		security_sk_clone(parent, sk);
564 	}
565 }
566 
567 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio, int kern)
568 {
569 	struct sock *sk;
570 	struct iucv_sock *iucv;
571 
572 	sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto, kern);
573 	if (!sk)
574 		return NULL;
575 	iucv = iucv_sk(sk);
576 
577 	sock_init_data(sock, sk);
578 	INIT_LIST_HEAD(&iucv->accept_q);
579 	spin_lock_init(&iucv->accept_q_lock);
580 	skb_queue_head_init(&iucv->send_skb_q);
581 	INIT_LIST_HEAD(&iucv->message_q.list);
582 	spin_lock_init(&iucv->message_q.lock);
583 	skb_queue_head_init(&iucv->backlog_skb_q);
584 	iucv->send_tag = 0;
585 	atomic_set(&iucv->pendings, 0);
586 	iucv->flags = 0;
587 	iucv->msglimit = 0;
588 	atomic_set(&iucv->msg_sent, 0);
589 	atomic_set(&iucv->msg_recv, 0);
590 	iucv->path = NULL;
591 	iucv->sk_txnotify = afiucv_hs_callback_txnotify;
592 	memset(&iucv->src_user_id , 0, 32);
593 	if (pr_iucv)
594 		iucv->transport = AF_IUCV_TRANS_IUCV;
595 	else
596 		iucv->transport = AF_IUCV_TRANS_HIPER;
597 
598 	sk->sk_destruct = iucv_sock_destruct;
599 	sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
600 
601 	sock_reset_flag(sk, SOCK_ZAPPED);
602 
603 	sk->sk_protocol = proto;
604 	sk->sk_state	= IUCV_OPEN;
605 
606 	iucv_sock_link(&iucv_sk_list, sk);
607 	return sk;
608 }
609 
610 /* Create an IUCV socket */
611 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
612 			    int kern)
613 {
614 	struct sock *sk;
615 
616 	if (protocol && protocol != PF_IUCV)
617 		return -EPROTONOSUPPORT;
618 
619 	sock->state = SS_UNCONNECTED;
620 
621 	switch (sock->type) {
622 	case SOCK_STREAM:
623 		sock->ops = &iucv_sock_ops;
624 		break;
625 	case SOCK_SEQPACKET:
626 		/* currently, proto ops can handle both sk types */
627 		sock->ops = &iucv_sock_ops;
628 		break;
629 	default:
630 		return -ESOCKTNOSUPPORT;
631 	}
632 
633 	sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL, kern);
634 	if (!sk)
635 		return -ENOMEM;
636 
637 	iucv_sock_init(sk, NULL);
638 
639 	return 0;
640 }
641 
642 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
643 {
644 	write_lock_bh(&l->lock);
645 	sk_add_node(sk, &l->head);
646 	write_unlock_bh(&l->lock);
647 }
648 
649 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
650 {
651 	write_lock_bh(&l->lock);
652 	sk_del_node_init(sk);
653 	write_unlock_bh(&l->lock);
654 }
655 
656 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
657 {
658 	unsigned long flags;
659 	struct iucv_sock *par = iucv_sk(parent);
660 
661 	sock_hold(sk);
662 	spin_lock_irqsave(&par->accept_q_lock, flags);
663 	list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
664 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
665 	iucv_sk(sk)->parent = parent;
666 	sk_acceptq_added(parent);
667 }
668 
669 void iucv_accept_unlink(struct sock *sk)
670 {
671 	unsigned long flags;
672 	struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
673 
674 	spin_lock_irqsave(&par->accept_q_lock, flags);
675 	list_del_init(&iucv_sk(sk)->accept_q);
676 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
677 	sk_acceptq_removed(iucv_sk(sk)->parent);
678 	iucv_sk(sk)->parent = NULL;
679 	sock_put(sk);
680 }
681 
682 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
683 {
684 	struct iucv_sock *isk, *n;
685 	struct sock *sk;
686 
687 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
688 		sk = (struct sock *) isk;
689 		lock_sock(sk);
690 
691 		if (sk->sk_state == IUCV_CLOSED) {
692 			iucv_accept_unlink(sk);
693 			release_sock(sk);
694 			continue;
695 		}
696 
697 		if (sk->sk_state == IUCV_CONNECTED ||
698 		    sk->sk_state == IUCV_DISCONN ||
699 		    !newsock) {
700 			iucv_accept_unlink(sk);
701 			if (newsock)
702 				sock_graft(sk, newsock);
703 
704 			release_sock(sk);
705 			return sk;
706 		}
707 
708 		release_sock(sk);
709 	}
710 	return NULL;
711 }
712 
713 static void __iucv_auto_name(struct iucv_sock *iucv)
714 {
715 	char name[12];
716 
717 	sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
718 	while (__iucv_get_sock_by_name(name)) {
719 		sprintf(name, "%08x",
720 			atomic_inc_return(&iucv_sk_list.autobind_name));
721 	}
722 	memcpy(iucv->src_name, name, 8);
723 }
724 
725 /* Bind an unbound socket */
726 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
727 			  int addr_len)
728 {
729 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
730 	struct sock *sk = sock->sk;
731 	struct iucv_sock *iucv;
732 	int err = 0;
733 	struct net_device *dev;
734 	char uid[9];
735 
736 	/* Verify the input sockaddr */
737 	if (addr_len < sizeof(struct sockaddr_iucv) ||
738 	    addr->sa_family != AF_IUCV)
739 		return -EINVAL;
740 
741 	lock_sock(sk);
742 	if (sk->sk_state != IUCV_OPEN) {
743 		err = -EBADFD;
744 		goto done;
745 	}
746 
747 	write_lock_bh(&iucv_sk_list.lock);
748 
749 	iucv = iucv_sk(sk);
750 	if (__iucv_get_sock_by_name(sa->siucv_name)) {
751 		err = -EADDRINUSE;
752 		goto done_unlock;
753 	}
754 	if (iucv->path)
755 		goto done_unlock;
756 
757 	/* Bind the socket */
758 	if (pr_iucv)
759 		if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
760 			goto vm_bind; /* VM IUCV transport */
761 
762 	/* try hiper transport */
763 	memcpy(uid, sa->siucv_user_id, sizeof(uid));
764 	ASCEBC(uid, 8);
765 	rcu_read_lock();
766 	for_each_netdev_rcu(&init_net, dev) {
767 		if (!memcmp(dev->perm_addr, uid, 8)) {
768 			memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
769 			/* Check for unitialized siucv_name */
770 			if (strncmp(sa->siucv_name, "        ", 8) == 0)
771 				__iucv_auto_name(iucv);
772 			else
773 				memcpy(iucv->src_name, sa->siucv_name, 8);
774 			sk->sk_bound_dev_if = dev->ifindex;
775 			iucv->hs_dev = dev;
776 			dev_hold(dev);
777 			sk->sk_state = IUCV_BOUND;
778 			iucv->transport = AF_IUCV_TRANS_HIPER;
779 			if (!iucv->msglimit)
780 				iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
781 			rcu_read_unlock();
782 			goto done_unlock;
783 		}
784 	}
785 	rcu_read_unlock();
786 vm_bind:
787 	if (pr_iucv) {
788 		/* use local userid for backward compat */
789 		memcpy(iucv->src_name, sa->siucv_name, 8);
790 		memcpy(iucv->src_user_id, iucv_userid, 8);
791 		sk->sk_state = IUCV_BOUND;
792 		iucv->transport = AF_IUCV_TRANS_IUCV;
793 		sk->sk_allocation |= GFP_DMA;
794 		if (!iucv->msglimit)
795 			iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
796 		goto done_unlock;
797 	}
798 	/* found no dev to bind */
799 	err = -ENODEV;
800 done_unlock:
801 	/* Release the socket list lock */
802 	write_unlock_bh(&iucv_sk_list.lock);
803 done:
804 	release_sock(sk);
805 	return err;
806 }
807 
808 /* Automatically bind an unbound socket */
809 static int iucv_sock_autobind(struct sock *sk)
810 {
811 	struct iucv_sock *iucv = iucv_sk(sk);
812 	int err = 0;
813 
814 	if (unlikely(!pr_iucv))
815 		return -EPROTO;
816 
817 	memcpy(iucv->src_user_id, iucv_userid, 8);
818 	iucv->transport = AF_IUCV_TRANS_IUCV;
819 	sk->sk_allocation |= GFP_DMA;
820 
821 	write_lock_bh(&iucv_sk_list.lock);
822 	__iucv_auto_name(iucv);
823 	write_unlock_bh(&iucv_sk_list.lock);
824 
825 	if (!iucv->msglimit)
826 		iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
827 
828 	return err;
829 }
830 
831 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
832 {
833 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
834 	struct sock *sk = sock->sk;
835 	struct iucv_sock *iucv = iucv_sk(sk);
836 	unsigned char user_data[16];
837 	int err;
838 
839 	high_nmcpy(user_data, sa->siucv_name);
840 	low_nmcpy(user_data, iucv->src_name);
841 	ASCEBC(user_data, sizeof(user_data));
842 
843 	/* Create path. */
844 	iucv->path = iucv_path_alloc(iucv->msglimit,
845 				     IUCV_IPRMDATA, GFP_KERNEL);
846 	if (!iucv->path) {
847 		err = -ENOMEM;
848 		goto done;
849 	}
850 	err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
851 				    sa->siucv_user_id, NULL, user_data,
852 				    sk);
853 	if (err) {
854 		iucv_path_free(iucv->path);
855 		iucv->path = NULL;
856 		switch (err) {
857 		case 0x0b:	/* Target communicator is not logged on */
858 			err = -ENETUNREACH;
859 			break;
860 		case 0x0d:	/* Max connections for this guest exceeded */
861 		case 0x0e:	/* Max connections for target guest exceeded */
862 			err = -EAGAIN;
863 			break;
864 		case 0x0f:	/* Missing IUCV authorization */
865 			err = -EACCES;
866 			break;
867 		default:
868 			err = -ECONNREFUSED;
869 			break;
870 		}
871 	}
872 done:
873 	return err;
874 }
875 
876 /* Connect an unconnected socket */
877 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
878 			     int alen, int flags)
879 {
880 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
881 	struct sock *sk = sock->sk;
882 	struct iucv_sock *iucv = iucv_sk(sk);
883 	int err;
884 
885 	if (alen < sizeof(struct sockaddr_iucv) || addr->sa_family != AF_IUCV)
886 		return -EINVAL;
887 
888 	if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
889 		return -EBADFD;
890 
891 	if (sk->sk_state == IUCV_OPEN &&
892 	    iucv->transport == AF_IUCV_TRANS_HIPER)
893 		return -EBADFD; /* explicit bind required */
894 
895 	if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
896 		return -EINVAL;
897 
898 	if (sk->sk_state == IUCV_OPEN) {
899 		err = iucv_sock_autobind(sk);
900 		if (unlikely(err))
901 			return err;
902 	}
903 
904 	lock_sock(sk);
905 
906 	/* Set the destination information */
907 	memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
908 	memcpy(iucv->dst_name, sa->siucv_name, 8);
909 
910 	if (iucv->transport == AF_IUCV_TRANS_HIPER)
911 		err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
912 	else
913 		err = afiucv_path_connect(sock, addr);
914 	if (err)
915 		goto done;
916 
917 	if (sk->sk_state != IUCV_CONNECTED)
918 		err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
919 							    IUCV_DISCONN),
920 				     sock_sndtimeo(sk, flags & O_NONBLOCK));
921 
922 	if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
923 		err = -ECONNREFUSED;
924 
925 	if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
926 		iucv_sever_path(sk, 0);
927 
928 done:
929 	release_sock(sk);
930 	return err;
931 }
932 
933 /* Move a socket into listening state. */
934 static int iucv_sock_listen(struct socket *sock, int backlog)
935 {
936 	struct sock *sk = sock->sk;
937 	int err;
938 
939 	lock_sock(sk);
940 
941 	err = -EINVAL;
942 	if (sk->sk_state != IUCV_BOUND)
943 		goto done;
944 
945 	if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
946 		goto done;
947 
948 	sk->sk_max_ack_backlog = backlog;
949 	sk->sk_ack_backlog = 0;
950 	sk->sk_state = IUCV_LISTEN;
951 	err = 0;
952 
953 done:
954 	release_sock(sk);
955 	return err;
956 }
957 
958 /* Accept a pending connection */
959 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
960 			    int flags, bool kern)
961 {
962 	DECLARE_WAITQUEUE(wait, current);
963 	struct sock *sk = sock->sk, *nsk;
964 	long timeo;
965 	int err = 0;
966 
967 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
968 
969 	if (sk->sk_state != IUCV_LISTEN) {
970 		err = -EBADFD;
971 		goto done;
972 	}
973 
974 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
975 
976 	/* Wait for an incoming connection */
977 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
978 	while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
979 		set_current_state(TASK_INTERRUPTIBLE);
980 		if (!timeo) {
981 			err = -EAGAIN;
982 			break;
983 		}
984 
985 		release_sock(sk);
986 		timeo = schedule_timeout(timeo);
987 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
988 
989 		if (sk->sk_state != IUCV_LISTEN) {
990 			err = -EBADFD;
991 			break;
992 		}
993 
994 		if (signal_pending(current)) {
995 			err = sock_intr_errno(timeo);
996 			break;
997 		}
998 	}
999 
1000 	set_current_state(TASK_RUNNING);
1001 	remove_wait_queue(sk_sleep(sk), &wait);
1002 
1003 	if (err)
1004 		goto done;
1005 
1006 	newsock->state = SS_CONNECTED;
1007 
1008 done:
1009 	release_sock(sk);
1010 	return err;
1011 }
1012 
1013 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
1014 			     int peer)
1015 {
1016 	struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
1017 	struct sock *sk = sock->sk;
1018 	struct iucv_sock *iucv = iucv_sk(sk);
1019 
1020 	addr->sa_family = AF_IUCV;
1021 
1022 	if (peer) {
1023 		memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
1024 		memcpy(siucv->siucv_name, iucv->dst_name, 8);
1025 	} else {
1026 		memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
1027 		memcpy(siucv->siucv_name, iucv->src_name, 8);
1028 	}
1029 	memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
1030 	memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
1031 	memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
1032 
1033 	return sizeof(struct sockaddr_iucv);
1034 }
1035 
1036 /**
1037  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1038  * @path:	IUCV path
1039  * @msg:	Pointer to a struct iucv_message
1040  * @skb:	The socket data to send, skb->len MUST BE <= 7
1041  *
1042  * Send the socket data in the parameter list in the iucv message
1043  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1044  * list and the socket data len at index 7 (last byte).
1045  * See also iucv_msg_length().
1046  *
1047  * Returns the error code from the iucv_message_send() call.
1048  */
1049 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1050 			  struct sk_buff *skb)
1051 {
1052 	u8 prmdata[8];
1053 
1054 	memcpy(prmdata, (void *) skb->data, skb->len);
1055 	prmdata[7] = 0xff - (u8) skb->len;
1056 	return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1057 				 (void *) prmdata, 8);
1058 }
1059 
1060 static int iucv_sock_sendmsg(struct socket *sock, struct msghdr *msg,
1061 			     size_t len)
1062 {
1063 	struct sock *sk = sock->sk;
1064 	struct iucv_sock *iucv = iucv_sk(sk);
1065 	size_t headroom = 0;
1066 	size_t linear;
1067 	struct sk_buff *skb;
1068 	struct iucv_message txmsg = {0};
1069 	struct cmsghdr *cmsg;
1070 	int cmsg_done;
1071 	long timeo;
1072 	char user_id[9];
1073 	char appl_id[9];
1074 	int err;
1075 	int noblock = msg->msg_flags & MSG_DONTWAIT;
1076 
1077 	err = sock_error(sk);
1078 	if (err)
1079 		return err;
1080 
1081 	if (msg->msg_flags & MSG_OOB)
1082 		return -EOPNOTSUPP;
1083 
1084 	/* SOCK_SEQPACKET: we do not support segmented records */
1085 	if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1086 		return -EOPNOTSUPP;
1087 
1088 	lock_sock(sk);
1089 
1090 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1091 		err = -EPIPE;
1092 		goto out;
1093 	}
1094 
1095 	/* Return if the socket is not in connected state */
1096 	if (sk->sk_state != IUCV_CONNECTED) {
1097 		err = -ENOTCONN;
1098 		goto out;
1099 	}
1100 
1101 	/* initialize defaults */
1102 	cmsg_done   = 0;	/* check for duplicate headers */
1103 	txmsg.class = 0;
1104 
1105 	/* iterate over control messages */
1106 	for_each_cmsghdr(cmsg, msg) {
1107 		if (!CMSG_OK(msg, cmsg)) {
1108 			err = -EINVAL;
1109 			goto out;
1110 		}
1111 
1112 		if (cmsg->cmsg_level != SOL_IUCV)
1113 			continue;
1114 
1115 		if (cmsg->cmsg_type & cmsg_done) {
1116 			err = -EINVAL;
1117 			goto out;
1118 		}
1119 		cmsg_done |= cmsg->cmsg_type;
1120 
1121 		switch (cmsg->cmsg_type) {
1122 		case SCM_IUCV_TRGCLS:
1123 			if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1124 				err = -EINVAL;
1125 				goto out;
1126 			}
1127 
1128 			/* set iucv message target class */
1129 			memcpy(&txmsg.class,
1130 				(void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1131 
1132 			break;
1133 
1134 		default:
1135 			err = -EINVAL;
1136 			goto out;
1137 		}
1138 	}
1139 
1140 	/* allocate one skb for each iucv message:
1141 	 * this is fine for SOCK_SEQPACKET (unless we want to support
1142 	 * segmented records using the MSG_EOR flag), but
1143 	 * for SOCK_STREAM we might want to improve it in future */
1144 	if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1145 		headroom = sizeof(struct af_iucv_trans_hdr) +
1146 			   LL_RESERVED_SPACE(iucv->hs_dev);
1147 		linear = len;
1148 	} else {
1149 		if (len < PAGE_SIZE) {
1150 			linear = len;
1151 		} else {
1152 			/* In nonlinear "classic" iucv skb,
1153 			 * reserve space for iucv_array
1154 			 */
1155 			headroom = sizeof(struct iucv_array) *
1156 				   (MAX_SKB_FRAGS + 1);
1157 			linear = PAGE_SIZE - headroom;
1158 		}
1159 	}
1160 	skb = sock_alloc_send_pskb(sk, headroom + linear, len - linear,
1161 				   noblock, &err, 0);
1162 	if (!skb)
1163 		goto out;
1164 	if (headroom)
1165 		skb_reserve(skb, headroom);
1166 	skb_put(skb, linear);
1167 	skb->len = len;
1168 	skb->data_len = len - linear;
1169 	err = skb_copy_datagram_from_iter(skb, 0, &msg->msg_iter, len);
1170 	if (err)
1171 		goto fail;
1172 
1173 	/* wait if outstanding messages for iucv path has reached */
1174 	timeo = sock_sndtimeo(sk, noblock);
1175 	err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1176 	if (err)
1177 		goto fail;
1178 
1179 	/* return -ECONNRESET if the socket is no longer connected */
1180 	if (sk->sk_state != IUCV_CONNECTED) {
1181 		err = -ECONNRESET;
1182 		goto fail;
1183 	}
1184 
1185 	/* increment and save iucv message tag for msg_completion cbk */
1186 	txmsg.tag = iucv->send_tag++;
1187 	IUCV_SKB_CB(skb)->tag = txmsg.tag;
1188 
1189 	if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1190 		atomic_inc(&iucv->msg_sent);
1191 		err = afiucv_hs_send(&txmsg, sk, skb, 0);
1192 		if (err) {
1193 			atomic_dec(&iucv->msg_sent);
1194 			goto out;
1195 		}
1196 	} else { /* Classic VM IUCV transport */
1197 		skb_queue_tail(&iucv->send_skb_q, skb);
1198 
1199 		if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags) &&
1200 		    skb->len <= 7) {
1201 			err = iucv_send_iprm(iucv->path, &txmsg, skb);
1202 
1203 			/* on success: there is no message_complete callback */
1204 			/* for an IPRMDATA msg; remove skb from send queue   */
1205 			if (err == 0) {
1206 				skb_unlink(skb, &iucv->send_skb_q);
1207 				kfree_skb(skb);
1208 			}
1209 
1210 			/* this error should never happen since the	*/
1211 			/* IUCV_IPRMDATA path flag is set... sever path */
1212 			if (err == 0x15) {
1213 				pr_iucv->path_sever(iucv->path, NULL);
1214 				skb_unlink(skb, &iucv->send_skb_q);
1215 				err = -EPIPE;
1216 				goto fail;
1217 			}
1218 		} else if (skb_is_nonlinear(skb)) {
1219 			struct iucv_array *iba = (struct iucv_array *)skb->head;
1220 			int i;
1221 
1222 			/* skip iucv_array lying in the headroom */
1223 			iba[0].address = (u32)(addr_t)skb->data;
1224 			iba[0].length = (u32)skb_headlen(skb);
1225 			for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1226 				skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1227 
1228 				iba[i + 1].address =
1229 					(u32)(addr_t)skb_frag_address(frag);
1230 				iba[i + 1].length = (u32)skb_frag_size(frag);
1231 			}
1232 			err = pr_iucv->message_send(iucv->path, &txmsg,
1233 						    IUCV_IPBUFLST, 0,
1234 						    (void *)iba, skb->len);
1235 		} else { /* non-IPRM Linear skb */
1236 			err = pr_iucv->message_send(iucv->path, &txmsg,
1237 					0, 0, (void *)skb->data, skb->len);
1238 		}
1239 		if (err) {
1240 			if (err == 3) {
1241 				user_id[8] = 0;
1242 				memcpy(user_id, iucv->dst_user_id, 8);
1243 				appl_id[8] = 0;
1244 				memcpy(appl_id, iucv->dst_name, 8);
1245 				pr_err(
1246 		"Application %s on z/VM guest %s exceeds message limit\n",
1247 					appl_id, user_id);
1248 				err = -EAGAIN;
1249 			} else {
1250 				err = -EPIPE;
1251 			}
1252 			skb_unlink(skb, &iucv->send_skb_q);
1253 			goto fail;
1254 		}
1255 	}
1256 
1257 	release_sock(sk);
1258 	return len;
1259 
1260 fail:
1261 	kfree_skb(skb);
1262 out:
1263 	release_sock(sk);
1264 	return err;
1265 }
1266 
1267 static struct sk_buff *alloc_iucv_recv_skb(unsigned long len)
1268 {
1269 	size_t headroom, linear;
1270 	struct sk_buff *skb;
1271 	int err;
1272 
1273 	if (len < PAGE_SIZE) {
1274 		headroom = 0;
1275 		linear = len;
1276 	} else {
1277 		headroom = sizeof(struct iucv_array) * (MAX_SKB_FRAGS + 1);
1278 		linear = PAGE_SIZE - headroom;
1279 	}
1280 	skb = alloc_skb_with_frags(headroom + linear, len - linear,
1281 				   0, &err, GFP_ATOMIC | GFP_DMA);
1282 	WARN_ONCE(!skb,
1283 		  "alloc of recv iucv skb len=%lu failed with errcode=%d\n",
1284 		  len, err);
1285 	if (skb) {
1286 		if (headroom)
1287 			skb_reserve(skb, headroom);
1288 		skb_put(skb, linear);
1289 		skb->len = len;
1290 		skb->data_len = len - linear;
1291 	}
1292 	return skb;
1293 }
1294 
1295 /* iucv_process_message() - Receive a single outstanding IUCV message
1296  *
1297  * Locking: must be called with message_q.lock held
1298  */
1299 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1300 				 struct iucv_path *path,
1301 				 struct iucv_message *msg)
1302 {
1303 	int rc;
1304 	unsigned int len;
1305 
1306 	len = iucv_msg_length(msg);
1307 
1308 	/* store msg target class in the second 4 bytes of skb ctrl buffer */
1309 	/* Note: the first 4 bytes are reserved for msg tag */
1310 	IUCV_SKB_CB(skb)->class = msg->class;
1311 
1312 	/* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1313 	if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1314 		if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1315 			skb->data = NULL;
1316 			skb->len = 0;
1317 		}
1318 	} else {
1319 		if (skb_is_nonlinear(skb)) {
1320 			struct iucv_array *iba = (struct iucv_array *)skb->head;
1321 			int i;
1322 
1323 			iba[0].address = (u32)(addr_t)skb->data;
1324 			iba[0].length = (u32)skb_headlen(skb);
1325 			for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
1326 				skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
1327 
1328 				iba[i + 1].address =
1329 					(u32)(addr_t)skb_frag_address(frag);
1330 				iba[i + 1].length = (u32)skb_frag_size(frag);
1331 			}
1332 			rc = pr_iucv->message_receive(path, msg,
1333 					      IUCV_IPBUFLST,
1334 					      (void *)iba, len, NULL);
1335 		} else {
1336 			rc = pr_iucv->message_receive(path, msg,
1337 					      msg->flags & IUCV_IPRMDATA,
1338 					      skb->data, len, NULL);
1339 		}
1340 		if (rc) {
1341 			kfree_skb(skb);
1342 			return;
1343 		}
1344 		WARN_ON_ONCE(skb->len != len);
1345 	}
1346 
1347 	IUCV_SKB_CB(skb)->offset = 0;
1348 	if (sk_filter(sk, skb)) {
1349 		atomic_inc(&sk->sk_drops);	/* skb rejected by filter */
1350 		kfree_skb(skb);
1351 		return;
1352 	}
1353 	if (__sock_queue_rcv_skb(sk, skb))	/* handle rcv queue full */
1354 		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
1355 }
1356 
1357 /* iucv_process_message_q() - Process outstanding IUCV messages
1358  *
1359  * Locking: must be called with message_q.lock held
1360  */
1361 static void iucv_process_message_q(struct sock *sk)
1362 {
1363 	struct iucv_sock *iucv = iucv_sk(sk);
1364 	struct sk_buff *skb;
1365 	struct sock_msg_q *p, *n;
1366 
1367 	list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1368 		skb = alloc_iucv_recv_skb(iucv_msg_length(&p->msg));
1369 		if (!skb)
1370 			break;
1371 		iucv_process_message(sk, skb, p->path, &p->msg);
1372 		list_del(&p->list);
1373 		kfree(p);
1374 		if (!skb_queue_empty(&iucv->backlog_skb_q))
1375 			break;
1376 	}
1377 }
1378 
1379 static int iucv_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1380 			     size_t len, int flags)
1381 {
1382 	int noblock = flags & MSG_DONTWAIT;
1383 	struct sock *sk = sock->sk;
1384 	struct iucv_sock *iucv = iucv_sk(sk);
1385 	unsigned int copied, rlen;
1386 	struct sk_buff *skb, *rskb, *cskb;
1387 	int err = 0;
1388 	u32 offset;
1389 
1390 	if ((sk->sk_state == IUCV_DISCONN) &&
1391 	    skb_queue_empty(&iucv->backlog_skb_q) &&
1392 	    skb_queue_empty(&sk->sk_receive_queue) &&
1393 	    list_empty(&iucv->message_q.list))
1394 		return 0;
1395 
1396 	if (flags & (MSG_OOB))
1397 		return -EOPNOTSUPP;
1398 
1399 	/* receive/dequeue next skb:
1400 	 * the function understands MSG_PEEK and, thus, does not dequeue skb */
1401 	skb = skb_recv_datagram(sk, flags, noblock, &err);
1402 	if (!skb) {
1403 		if (sk->sk_shutdown & RCV_SHUTDOWN)
1404 			return 0;
1405 		return err;
1406 	}
1407 
1408 	offset = IUCV_SKB_CB(skb)->offset;
1409 	rlen   = skb->len - offset;		/* real length of skb */
1410 	copied = min_t(unsigned int, rlen, len);
1411 	if (!rlen)
1412 		sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1413 
1414 	cskb = skb;
1415 	if (skb_copy_datagram_msg(cskb, offset, msg, copied)) {
1416 		if (!(flags & MSG_PEEK))
1417 			skb_queue_head(&sk->sk_receive_queue, skb);
1418 		return -EFAULT;
1419 	}
1420 
1421 	/* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1422 	if (sk->sk_type == SOCK_SEQPACKET) {
1423 		if (copied < rlen)
1424 			msg->msg_flags |= MSG_TRUNC;
1425 		/* each iucv message contains a complete record */
1426 		msg->msg_flags |= MSG_EOR;
1427 	}
1428 
1429 	/* create control message to store iucv msg target class:
1430 	 * get the trgcls from the control buffer of the skb due to
1431 	 * fragmentation of original iucv message. */
1432 	err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1433 		       sizeof(IUCV_SKB_CB(skb)->class),
1434 		       (void *)&IUCV_SKB_CB(skb)->class);
1435 	if (err) {
1436 		if (!(flags & MSG_PEEK))
1437 			skb_queue_head(&sk->sk_receive_queue, skb);
1438 		return err;
1439 	}
1440 
1441 	/* Mark read part of skb as used */
1442 	if (!(flags & MSG_PEEK)) {
1443 
1444 		/* SOCK_STREAM: re-queue skb if it contains unreceived data */
1445 		if (sk->sk_type == SOCK_STREAM) {
1446 			if (copied < rlen) {
1447 				IUCV_SKB_CB(skb)->offset = offset + copied;
1448 				skb_queue_head(&sk->sk_receive_queue, skb);
1449 				goto done;
1450 			}
1451 		}
1452 
1453 		kfree_skb(skb);
1454 		if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1455 			atomic_inc(&iucv->msg_recv);
1456 			if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1457 				WARN_ON(1);
1458 				iucv_sock_close(sk);
1459 				return -EFAULT;
1460 			}
1461 		}
1462 
1463 		/* Queue backlog skbs */
1464 		spin_lock_bh(&iucv->message_q.lock);
1465 		rskb = skb_dequeue(&iucv->backlog_skb_q);
1466 		while (rskb) {
1467 			IUCV_SKB_CB(rskb)->offset = 0;
1468 			if (__sock_queue_rcv_skb(sk, rskb)) {
1469 				/* handle rcv queue full */
1470 				skb_queue_head(&iucv->backlog_skb_q,
1471 						rskb);
1472 				break;
1473 			}
1474 			rskb = skb_dequeue(&iucv->backlog_skb_q);
1475 		}
1476 		if (skb_queue_empty(&iucv->backlog_skb_q)) {
1477 			if (!list_empty(&iucv->message_q.list))
1478 				iucv_process_message_q(sk);
1479 			if (atomic_read(&iucv->msg_recv) >=
1480 							iucv->msglimit / 2) {
1481 				err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1482 				if (err) {
1483 					sk->sk_state = IUCV_DISCONN;
1484 					sk->sk_state_change(sk);
1485 				}
1486 			}
1487 		}
1488 		spin_unlock_bh(&iucv->message_q.lock);
1489 	}
1490 
1491 done:
1492 	/* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1493 	if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1494 		copied = rlen;
1495 
1496 	return copied;
1497 }
1498 
1499 static inline __poll_t iucv_accept_poll(struct sock *parent)
1500 {
1501 	struct iucv_sock *isk, *n;
1502 	struct sock *sk;
1503 
1504 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1505 		sk = (struct sock *) isk;
1506 
1507 		if (sk->sk_state == IUCV_CONNECTED)
1508 			return EPOLLIN | EPOLLRDNORM;
1509 	}
1510 
1511 	return 0;
1512 }
1513 
1514 __poll_t iucv_sock_poll(struct file *file, struct socket *sock,
1515 			    poll_table *wait)
1516 {
1517 	struct sock *sk = sock->sk;
1518 	__poll_t mask = 0;
1519 
1520 	sock_poll_wait(file, sock, wait);
1521 
1522 	if (sk->sk_state == IUCV_LISTEN)
1523 		return iucv_accept_poll(sk);
1524 
1525 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1526 		mask |= EPOLLERR |
1527 			(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? EPOLLPRI : 0);
1528 
1529 	if (sk->sk_shutdown & RCV_SHUTDOWN)
1530 		mask |= EPOLLRDHUP;
1531 
1532 	if (sk->sk_shutdown == SHUTDOWN_MASK)
1533 		mask |= EPOLLHUP;
1534 
1535 	if (!skb_queue_empty(&sk->sk_receive_queue) ||
1536 	    (sk->sk_shutdown & RCV_SHUTDOWN))
1537 		mask |= EPOLLIN | EPOLLRDNORM;
1538 
1539 	if (sk->sk_state == IUCV_CLOSED)
1540 		mask |= EPOLLHUP;
1541 
1542 	if (sk->sk_state == IUCV_DISCONN)
1543 		mask |= EPOLLIN;
1544 
1545 	if (sock_writeable(sk) && iucv_below_msglim(sk))
1546 		mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
1547 	else
1548 		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
1549 
1550 	return mask;
1551 }
1552 
1553 static int iucv_sock_shutdown(struct socket *sock, int how)
1554 {
1555 	struct sock *sk = sock->sk;
1556 	struct iucv_sock *iucv = iucv_sk(sk);
1557 	struct iucv_message txmsg;
1558 	int err = 0;
1559 
1560 	how++;
1561 
1562 	if ((how & ~SHUTDOWN_MASK) || !how)
1563 		return -EINVAL;
1564 
1565 	lock_sock(sk);
1566 	switch (sk->sk_state) {
1567 	case IUCV_LISTEN:
1568 	case IUCV_DISCONN:
1569 	case IUCV_CLOSING:
1570 	case IUCV_CLOSED:
1571 		err = -ENOTCONN;
1572 		goto fail;
1573 	default:
1574 		break;
1575 	}
1576 
1577 	if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1578 		if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1579 			txmsg.class = 0;
1580 			txmsg.tag = 0;
1581 			err = pr_iucv->message_send(iucv->path, &txmsg,
1582 				IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1583 			if (err) {
1584 				switch (err) {
1585 				case 1:
1586 					err = -ENOTCONN;
1587 					break;
1588 				case 2:
1589 					err = -ECONNRESET;
1590 					break;
1591 				default:
1592 					err = -ENOTCONN;
1593 					break;
1594 				}
1595 			}
1596 		} else
1597 			iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1598 	}
1599 
1600 	sk->sk_shutdown |= how;
1601 	if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1602 		if ((iucv->transport == AF_IUCV_TRANS_IUCV) &&
1603 		    iucv->path) {
1604 			err = pr_iucv->path_quiesce(iucv->path, NULL);
1605 			if (err)
1606 				err = -ENOTCONN;
1607 /*			skb_queue_purge(&sk->sk_receive_queue); */
1608 		}
1609 		skb_queue_purge(&sk->sk_receive_queue);
1610 	}
1611 
1612 	/* Wake up anyone sleeping in poll */
1613 	sk->sk_state_change(sk);
1614 
1615 fail:
1616 	release_sock(sk);
1617 	return err;
1618 }
1619 
1620 static int iucv_sock_release(struct socket *sock)
1621 {
1622 	struct sock *sk = sock->sk;
1623 	int err = 0;
1624 
1625 	if (!sk)
1626 		return 0;
1627 
1628 	iucv_sock_close(sk);
1629 
1630 	sock_orphan(sk);
1631 	iucv_sock_kill(sk);
1632 	return err;
1633 }
1634 
1635 /* getsockopt and setsockopt */
1636 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1637 				char __user *optval, unsigned int optlen)
1638 {
1639 	struct sock *sk = sock->sk;
1640 	struct iucv_sock *iucv = iucv_sk(sk);
1641 	int val;
1642 	int rc;
1643 
1644 	if (level != SOL_IUCV)
1645 		return -ENOPROTOOPT;
1646 
1647 	if (optlen < sizeof(int))
1648 		return -EINVAL;
1649 
1650 	if (get_user(val, (int __user *) optval))
1651 		return -EFAULT;
1652 
1653 	rc = 0;
1654 
1655 	lock_sock(sk);
1656 	switch (optname) {
1657 	case SO_IPRMDATA_MSG:
1658 		if (val)
1659 			iucv->flags |= IUCV_IPRMDATA;
1660 		else
1661 			iucv->flags &= ~IUCV_IPRMDATA;
1662 		break;
1663 	case SO_MSGLIMIT:
1664 		switch (sk->sk_state) {
1665 		case IUCV_OPEN:
1666 		case IUCV_BOUND:
1667 			if (val < 1 || val > (u16)(~0))
1668 				rc = -EINVAL;
1669 			else
1670 				iucv->msglimit = val;
1671 			break;
1672 		default:
1673 			rc = -EINVAL;
1674 			break;
1675 		}
1676 		break;
1677 	default:
1678 		rc = -ENOPROTOOPT;
1679 		break;
1680 	}
1681 	release_sock(sk);
1682 
1683 	return rc;
1684 }
1685 
1686 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1687 				char __user *optval, int __user *optlen)
1688 {
1689 	struct sock *sk = sock->sk;
1690 	struct iucv_sock *iucv = iucv_sk(sk);
1691 	unsigned int val;
1692 	int len;
1693 
1694 	if (level != SOL_IUCV)
1695 		return -ENOPROTOOPT;
1696 
1697 	if (get_user(len, optlen))
1698 		return -EFAULT;
1699 
1700 	if (len < 0)
1701 		return -EINVAL;
1702 
1703 	len = min_t(unsigned int, len, sizeof(int));
1704 
1705 	switch (optname) {
1706 	case SO_IPRMDATA_MSG:
1707 		val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1708 		break;
1709 	case SO_MSGLIMIT:
1710 		lock_sock(sk);
1711 		val = (iucv->path != NULL) ? iucv->path->msglim	/* connected */
1712 					   : iucv->msglimit;	/* default */
1713 		release_sock(sk);
1714 		break;
1715 	case SO_MSGSIZE:
1716 		if (sk->sk_state == IUCV_OPEN)
1717 			return -EBADFD;
1718 		val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1719 				sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1720 				0x7fffffff;
1721 		break;
1722 	default:
1723 		return -ENOPROTOOPT;
1724 	}
1725 
1726 	if (put_user(len, optlen))
1727 		return -EFAULT;
1728 	if (copy_to_user(optval, &val, len))
1729 		return -EFAULT;
1730 
1731 	return 0;
1732 }
1733 
1734 
1735 /* Callback wrappers - called from iucv base support */
1736 static int iucv_callback_connreq(struct iucv_path *path,
1737 				 u8 ipvmid[8], u8 ipuser[16])
1738 {
1739 	unsigned char user_data[16];
1740 	unsigned char nuser_data[16];
1741 	unsigned char src_name[8];
1742 	struct sock *sk, *nsk;
1743 	struct iucv_sock *iucv, *niucv;
1744 	int err;
1745 
1746 	memcpy(src_name, ipuser, 8);
1747 	EBCASC(src_name, 8);
1748 	/* Find out if this path belongs to af_iucv. */
1749 	read_lock(&iucv_sk_list.lock);
1750 	iucv = NULL;
1751 	sk = NULL;
1752 	sk_for_each(sk, &iucv_sk_list.head)
1753 		if (sk->sk_state == IUCV_LISTEN &&
1754 		    !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1755 			/*
1756 			 * Found a listening socket with
1757 			 * src_name == ipuser[0-7].
1758 			 */
1759 			iucv = iucv_sk(sk);
1760 			break;
1761 		}
1762 	read_unlock(&iucv_sk_list.lock);
1763 	if (!iucv)
1764 		/* No socket found, not one of our paths. */
1765 		return -EINVAL;
1766 
1767 	bh_lock_sock(sk);
1768 
1769 	/* Check if parent socket is listening */
1770 	low_nmcpy(user_data, iucv->src_name);
1771 	high_nmcpy(user_data, iucv->dst_name);
1772 	ASCEBC(user_data, sizeof(user_data));
1773 	if (sk->sk_state != IUCV_LISTEN) {
1774 		err = pr_iucv->path_sever(path, user_data);
1775 		iucv_path_free(path);
1776 		goto fail;
1777 	}
1778 
1779 	/* Check for backlog size */
1780 	if (sk_acceptq_is_full(sk)) {
1781 		err = pr_iucv->path_sever(path, user_data);
1782 		iucv_path_free(path);
1783 		goto fail;
1784 	}
1785 
1786 	/* Create the new socket */
1787 	nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1788 	if (!nsk) {
1789 		err = pr_iucv->path_sever(path, user_data);
1790 		iucv_path_free(path);
1791 		goto fail;
1792 	}
1793 
1794 	niucv = iucv_sk(nsk);
1795 	iucv_sock_init(nsk, sk);
1796 	niucv->transport = AF_IUCV_TRANS_IUCV;
1797 	nsk->sk_allocation |= GFP_DMA;
1798 
1799 	/* Set the new iucv_sock */
1800 	memcpy(niucv->dst_name, ipuser + 8, 8);
1801 	EBCASC(niucv->dst_name, 8);
1802 	memcpy(niucv->dst_user_id, ipvmid, 8);
1803 	memcpy(niucv->src_name, iucv->src_name, 8);
1804 	memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1805 	niucv->path = path;
1806 
1807 	/* Call iucv_accept */
1808 	high_nmcpy(nuser_data, ipuser + 8);
1809 	memcpy(nuser_data + 8, niucv->src_name, 8);
1810 	ASCEBC(nuser_data + 8, 8);
1811 
1812 	/* set message limit for path based on msglimit of accepting socket */
1813 	niucv->msglimit = iucv->msglimit;
1814 	path->msglim = iucv->msglimit;
1815 	err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1816 	if (err) {
1817 		iucv_sever_path(nsk, 1);
1818 		iucv_sock_kill(nsk);
1819 		goto fail;
1820 	}
1821 
1822 	iucv_accept_enqueue(sk, nsk);
1823 
1824 	/* Wake up accept */
1825 	nsk->sk_state = IUCV_CONNECTED;
1826 	sk->sk_data_ready(sk);
1827 	err = 0;
1828 fail:
1829 	bh_unlock_sock(sk);
1830 	return 0;
1831 }
1832 
1833 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1834 {
1835 	struct sock *sk = path->private;
1836 
1837 	sk->sk_state = IUCV_CONNECTED;
1838 	sk->sk_state_change(sk);
1839 }
1840 
1841 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1842 {
1843 	struct sock *sk = path->private;
1844 	struct iucv_sock *iucv = iucv_sk(sk);
1845 	struct sk_buff *skb;
1846 	struct sock_msg_q *save_msg;
1847 	int len;
1848 
1849 	if (sk->sk_shutdown & RCV_SHUTDOWN) {
1850 		pr_iucv->message_reject(path, msg);
1851 		return;
1852 	}
1853 
1854 	spin_lock(&iucv->message_q.lock);
1855 
1856 	if (!list_empty(&iucv->message_q.list) ||
1857 	    !skb_queue_empty(&iucv->backlog_skb_q))
1858 		goto save_message;
1859 
1860 	len = atomic_read(&sk->sk_rmem_alloc);
1861 	len += SKB_TRUESIZE(iucv_msg_length(msg));
1862 	if (len > sk->sk_rcvbuf)
1863 		goto save_message;
1864 
1865 	skb = alloc_iucv_recv_skb(iucv_msg_length(msg));
1866 	if (!skb)
1867 		goto save_message;
1868 
1869 	iucv_process_message(sk, skb, path, msg);
1870 	goto out_unlock;
1871 
1872 save_message:
1873 	save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1874 	if (!save_msg)
1875 		goto out_unlock;
1876 	save_msg->path = path;
1877 	save_msg->msg = *msg;
1878 
1879 	list_add_tail(&save_msg->list, &iucv->message_q.list);
1880 
1881 out_unlock:
1882 	spin_unlock(&iucv->message_q.lock);
1883 }
1884 
1885 static void iucv_callback_txdone(struct iucv_path *path,
1886 				 struct iucv_message *msg)
1887 {
1888 	struct sock *sk = path->private;
1889 	struct sk_buff *this = NULL;
1890 	struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1891 	struct sk_buff *list_skb;
1892 	unsigned long flags;
1893 
1894 	bh_lock_sock(sk);
1895 
1896 	spin_lock_irqsave(&list->lock, flags);
1897 	skb_queue_walk(list, list_skb) {
1898 		if (msg->tag == IUCV_SKB_CB(list_skb)->tag) {
1899 			this = list_skb;
1900 			break;
1901 		}
1902 	}
1903 	if (this)
1904 		__skb_unlink(this, list);
1905 	spin_unlock_irqrestore(&list->lock, flags);
1906 
1907 	if (this) {
1908 		kfree_skb(this);
1909 		/* wake up any process waiting for sending */
1910 		iucv_sock_wake_msglim(sk);
1911 	}
1912 
1913 	if (sk->sk_state == IUCV_CLOSING) {
1914 		if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1915 			sk->sk_state = IUCV_CLOSED;
1916 			sk->sk_state_change(sk);
1917 		}
1918 	}
1919 	bh_unlock_sock(sk);
1920 
1921 }
1922 
1923 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1924 {
1925 	struct sock *sk = path->private;
1926 
1927 	if (sk->sk_state == IUCV_CLOSED)
1928 		return;
1929 
1930 	bh_lock_sock(sk);
1931 	iucv_sever_path(sk, 1);
1932 	sk->sk_state = IUCV_DISCONN;
1933 
1934 	sk->sk_state_change(sk);
1935 	bh_unlock_sock(sk);
1936 }
1937 
1938 /* called if the other communication side shuts down its RECV direction;
1939  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1940  */
1941 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1942 {
1943 	struct sock *sk = path->private;
1944 
1945 	bh_lock_sock(sk);
1946 	if (sk->sk_state != IUCV_CLOSED) {
1947 		sk->sk_shutdown |= SEND_SHUTDOWN;
1948 		sk->sk_state_change(sk);
1949 	}
1950 	bh_unlock_sock(sk);
1951 }
1952 
1953 /***************** HiperSockets transport callbacks ********************/
1954 static void afiucv_swap_src_dest(struct sk_buff *skb)
1955 {
1956 	struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1957 	char tmpID[8];
1958 	char tmpName[8];
1959 
1960 	ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1961 	ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1962 	ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1963 	ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1964 	memcpy(tmpID, trans_hdr->srcUserID, 8);
1965 	memcpy(tmpName, trans_hdr->srcAppName, 8);
1966 	memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1967 	memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1968 	memcpy(trans_hdr->destUserID, tmpID, 8);
1969 	memcpy(trans_hdr->destAppName, tmpName, 8);
1970 	skb_push(skb, ETH_HLEN);
1971 	memset(skb->data, 0, ETH_HLEN);
1972 }
1973 
1974 /**
1975  * afiucv_hs_callback_syn - react on received SYN
1976  **/
1977 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1978 {
1979 	struct af_iucv_trans_hdr *trans_hdr = iucv_trans_hdr(skb);
1980 	struct sock *nsk;
1981 	struct iucv_sock *iucv, *niucv;
1982 	int err;
1983 
1984 	iucv = iucv_sk(sk);
1985 	if (!iucv) {
1986 		/* no sock - connection refused */
1987 		afiucv_swap_src_dest(skb);
1988 		trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1989 		err = dev_queue_xmit(skb);
1990 		goto out;
1991 	}
1992 
1993 	nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC, 0);
1994 	bh_lock_sock(sk);
1995 	if ((sk->sk_state != IUCV_LISTEN) ||
1996 	    sk_acceptq_is_full(sk) ||
1997 	    !nsk) {
1998 		/* error on server socket - connection refused */
1999 		afiucv_swap_src_dest(skb);
2000 		trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
2001 		err = dev_queue_xmit(skb);
2002 		iucv_sock_kill(nsk);
2003 		bh_unlock_sock(sk);
2004 		goto out;
2005 	}
2006 
2007 	niucv = iucv_sk(nsk);
2008 	iucv_sock_init(nsk, sk);
2009 	niucv->transport = AF_IUCV_TRANS_HIPER;
2010 	niucv->msglimit = iucv->msglimit;
2011 	if (!trans_hdr->window)
2012 		niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
2013 	else
2014 		niucv->msglimit_peer = trans_hdr->window;
2015 	memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
2016 	memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
2017 	memcpy(niucv->src_name, iucv->src_name, 8);
2018 	memcpy(niucv->src_user_id, iucv->src_user_id, 8);
2019 	nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
2020 	niucv->hs_dev = iucv->hs_dev;
2021 	dev_hold(niucv->hs_dev);
2022 	afiucv_swap_src_dest(skb);
2023 	trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
2024 	trans_hdr->window = niucv->msglimit;
2025 	/* if receiver acks the xmit connection is established */
2026 	err = dev_queue_xmit(skb);
2027 	if (!err) {
2028 		iucv_accept_enqueue(sk, nsk);
2029 		nsk->sk_state = IUCV_CONNECTED;
2030 		sk->sk_data_ready(sk);
2031 	} else
2032 		iucv_sock_kill(nsk);
2033 	bh_unlock_sock(sk);
2034 
2035 out:
2036 	return NET_RX_SUCCESS;
2037 }
2038 
2039 /**
2040  * afiucv_hs_callback_synack() - react on received SYN-ACK
2041  **/
2042 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
2043 {
2044 	struct iucv_sock *iucv = iucv_sk(sk);
2045 
2046 	if (!iucv)
2047 		goto out;
2048 	if (sk->sk_state != IUCV_BOUND)
2049 		goto out;
2050 	bh_lock_sock(sk);
2051 	iucv->msglimit_peer = iucv_trans_hdr(skb)->window;
2052 	sk->sk_state = IUCV_CONNECTED;
2053 	sk->sk_state_change(sk);
2054 	bh_unlock_sock(sk);
2055 out:
2056 	kfree_skb(skb);
2057 	return NET_RX_SUCCESS;
2058 }
2059 
2060 /**
2061  * afiucv_hs_callback_synfin() - react on received SYN_FIN
2062  **/
2063 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2064 {
2065 	struct iucv_sock *iucv = iucv_sk(sk);
2066 
2067 	if (!iucv)
2068 		goto out;
2069 	if (sk->sk_state != IUCV_BOUND)
2070 		goto out;
2071 	bh_lock_sock(sk);
2072 	sk->sk_state = IUCV_DISCONN;
2073 	sk->sk_state_change(sk);
2074 	bh_unlock_sock(sk);
2075 out:
2076 	kfree_skb(skb);
2077 	return NET_RX_SUCCESS;
2078 }
2079 
2080 /**
2081  * afiucv_hs_callback_fin() - react on received FIN
2082  **/
2083 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2084 {
2085 	struct iucv_sock *iucv = iucv_sk(sk);
2086 
2087 	/* other end of connection closed */
2088 	if (!iucv)
2089 		goto out;
2090 	bh_lock_sock(sk);
2091 	if (sk->sk_state == IUCV_CONNECTED) {
2092 		sk->sk_state = IUCV_DISCONN;
2093 		sk->sk_state_change(sk);
2094 	}
2095 	bh_unlock_sock(sk);
2096 out:
2097 	kfree_skb(skb);
2098 	return NET_RX_SUCCESS;
2099 }
2100 
2101 /**
2102  * afiucv_hs_callback_win() - react on received WIN
2103  **/
2104 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2105 {
2106 	struct iucv_sock *iucv = iucv_sk(sk);
2107 
2108 	if (!iucv)
2109 		return NET_RX_SUCCESS;
2110 
2111 	if (sk->sk_state != IUCV_CONNECTED)
2112 		return NET_RX_SUCCESS;
2113 
2114 	atomic_sub(iucv_trans_hdr(skb)->window, &iucv->msg_sent);
2115 	iucv_sock_wake_msglim(sk);
2116 	return NET_RX_SUCCESS;
2117 }
2118 
2119 /**
2120  * afiucv_hs_callback_rx() - react on received data
2121  **/
2122 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2123 {
2124 	struct iucv_sock *iucv = iucv_sk(sk);
2125 
2126 	if (!iucv) {
2127 		kfree_skb(skb);
2128 		return NET_RX_SUCCESS;
2129 	}
2130 
2131 	if (sk->sk_state != IUCV_CONNECTED) {
2132 		kfree_skb(skb);
2133 		return NET_RX_SUCCESS;
2134 	}
2135 
2136 	if (sk->sk_shutdown & RCV_SHUTDOWN) {
2137 		kfree_skb(skb);
2138 		return NET_RX_SUCCESS;
2139 	}
2140 
2141 	/* write stuff from iucv_msg to skb cb */
2142 	skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2143 	skb_reset_transport_header(skb);
2144 	skb_reset_network_header(skb);
2145 	IUCV_SKB_CB(skb)->offset = 0;
2146 	if (sk_filter(sk, skb)) {
2147 		atomic_inc(&sk->sk_drops);	/* skb rejected by filter */
2148 		kfree_skb(skb);
2149 		return NET_RX_SUCCESS;
2150 	}
2151 
2152 	spin_lock(&iucv->message_q.lock);
2153 	if (skb_queue_empty(&iucv->backlog_skb_q)) {
2154 		if (__sock_queue_rcv_skb(sk, skb))
2155 			/* handle rcv queue full */
2156 			skb_queue_tail(&iucv->backlog_skb_q, skb);
2157 	} else
2158 		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2159 	spin_unlock(&iucv->message_q.lock);
2160 	return NET_RX_SUCCESS;
2161 }
2162 
2163 /**
2164  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2165  *                   transport
2166  *                   called from netif RX softirq
2167  **/
2168 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2169 	struct packet_type *pt, struct net_device *orig_dev)
2170 {
2171 	struct sock *sk;
2172 	struct iucv_sock *iucv;
2173 	struct af_iucv_trans_hdr *trans_hdr;
2174 	int err = NET_RX_SUCCESS;
2175 	char nullstring[8];
2176 
2177 	if (!pskb_may_pull(skb, sizeof(*trans_hdr))) {
2178 		WARN_ONCE(1, "AF_IUCV failed to receive skb, len=%u", skb->len);
2179 		kfree_skb(skb);
2180 		return NET_RX_SUCCESS;
2181 	}
2182 
2183 	trans_hdr = iucv_trans_hdr(skb);
2184 	EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2185 	EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2186 	EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2187 	EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2188 	memset(nullstring, 0, sizeof(nullstring));
2189 	iucv = NULL;
2190 	sk = NULL;
2191 	read_lock(&iucv_sk_list.lock);
2192 	sk_for_each(sk, &iucv_sk_list.head) {
2193 		if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2194 			if ((!memcmp(&iucv_sk(sk)->src_name,
2195 				     trans_hdr->destAppName, 8)) &&
2196 			    (!memcmp(&iucv_sk(sk)->src_user_id,
2197 				     trans_hdr->destUserID, 8)) &&
2198 			    (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2199 			    (!memcmp(&iucv_sk(sk)->dst_user_id,
2200 				     nullstring, 8))) {
2201 				iucv = iucv_sk(sk);
2202 				break;
2203 			}
2204 		} else {
2205 			if ((!memcmp(&iucv_sk(sk)->src_name,
2206 				     trans_hdr->destAppName, 8)) &&
2207 			    (!memcmp(&iucv_sk(sk)->src_user_id,
2208 				     trans_hdr->destUserID, 8)) &&
2209 			    (!memcmp(&iucv_sk(sk)->dst_name,
2210 				     trans_hdr->srcAppName, 8)) &&
2211 			    (!memcmp(&iucv_sk(sk)->dst_user_id,
2212 				     trans_hdr->srcUserID, 8))) {
2213 				iucv = iucv_sk(sk);
2214 				break;
2215 			}
2216 		}
2217 	}
2218 	read_unlock(&iucv_sk_list.lock);
2219 	if (!iucv)
2220 		sk = NULL;
2221 
2222 	/* no sock
2223 	how should we send with no sock
2224 	1) send without sock no send rc checking?
2225 	2) introduce default sock to handle this cases
2226 
2227 	 SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2228 	 data -> send FIN
2229 	 SYN|ACK, SYN|FIN, FIN -> no action? */
2230 
2231 	switch (trans_hdr->flags) {
2232 	case AF_IUCV_FLAG_SYN:
2233 		/* connect request */
2234 		err = afiucv_hs_callback_syn(sk, skb);
2235 		break;
2236 	case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2237 		/* connect request confirmed */
2238 		err = afiucv_hs_callback_synack(sk, skb);
2239 		break;
2240 	case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2241 		/* connect request refused */
2242 		err = afiucv_hs_callback_synfin(sk, skb);
2243 		break;
2244 	case (AF_IUCV_FLAG_FIN):
2245 		/* close request */
2246 		err = afiucv_hs_callback_fin(sk, skb);
2247 		break;
2248 	case (AF_IUCV_FLAG_WIN):
2249 		err = afiucv_hs_callback_win(sk, skb);
2250 		if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2251 			kfree_skb(skb);
2252 			break;
2253 		}
2254 		/* fall through - and receive non-zero length data */
2255 	case (AF_IUCV_FLAG_SHT):
2256 		/* shutdown request */
2257 		/* fall through - and receive zero length data */
2258 	case 0:
2259 		/* plain data frame */
2260 		IUCV_SKB_CB(skb)->class = trans_hdr->iucv_hdr.class;
2261 		err = afiucv_hs_callback_rx(sk, skb);
2262 		break;
2263 	default:
2264 		kfree_skb(skb);
2265 	}
2266 
2267 	return err;
2268 }
2269 
2270 /**
2271  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2272  *                                 transport
2273  **/
2274 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2275 					enum iucv_tx_notify n)
2276 {
2277 	struct sock *isk = skb->sk;
2278 	struct sock *sk = NULL;
2279 	struct iucv_sock *iucv = NULL;
2280 	struct sk_buff_head *list;
2281 	struct sk_buff *list_skb;
2282 	struct sk_buff *nskb;
2283 	unsigned long flags;
2284 
2285 	read_lock_irqsave(&iucv_sk_list.lock, flags);
2286 	sk_for_each(sk, &iucv_sk_list.head)
2287 		if (sk == isk) {
2288 			iucv = iucv_sk(sk);
2289 			break;
2290 		}
2291 	read_unlock_irqrestore(&iucv_sk_list.lock, flags);
2292 
2293 	if (!iucv || sock_flag(sk, SOCK_ZAPPED))
2294 		return;
2295 
2296 	list = &iucv->send_skb_q;
2297 	spin_lock_irqsave(&list->lock, flags);
2298 	skb_queue_walk_safe(list, list_skb, nskb) {
2299 		if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2300 			switch (n) {
2301 			case TX_NOTIFY_OK:
2302 				__skb_unlink(list_skb, list);
2303 				kfree_skb(list_skb);
2304 				iucv_sock_wake_msglim(sk);
2305 				break;
2306 			case TX_NOTIFY_PENDING:
2307 				atomic_inc(&iucv->pendings);
2308 				break;
2309 			case TX_NOTIFY_DELAYED_OK:
2310 				__skb_unlink(list_skb, list);
2311 				atomic_dec(&iucv->pendings);
2312 				if (atomic_read(&iucv->pendings) <= 0)
2313 					iucv_sock_wake_msglim(sk);
2314 				kfree_skb(list_skb);
2315 				break;
2316 			case TX_NOTIFY_UNREACHABLE:
2317 			case TX_NOTIFY_DELAYED_UNREACHABLE:
2318 			case TX_NOTIFY_TPQFULL: /* not yet used */
2319 			case TX_NOTIFY_GENERALERROR:
2320 			case TX_NOTIFY_DELAYED_GENERALERROR:
2321 				__skb_unlink(list_skb, list);
2322 				kfree_skb(list_skb);
2323 				if (sk->sk_state == IUCV_CONNECTED) {
2324 					sk->sk_state = IUCV_DISCONN;
2325 					sk->sk_state_change(sk);
2326 				}
2327 				break;
2328 			}
2329 			break;
2330 		}
2331 	}
2332 	spin_unlock_irqrestore(&list->lock, flags);
2333 
2334 	if (sk->sk_state == IUCV_CLOSING) {
2335 		if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
2336 			sk->sk_state = IUCV_CLOSED;
2337 			sk->sk_state_change(sk);
2338 		}
2339 	}
2340 
2341 }
2342 
2343 /*
2344  * afiucv_netdev_event: handle netdev notifier chain events
2345  */
2346 static int afiucv_netdev_event(struct notifier_block *this,
2347 			       unsigned long event, void *ptr)
2348 {
2349 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2350 	struct sock *sk;
2351 	struct iucv_sock *iucv;
2352 
2353 	switch (event) {
2354 	case NETDEV_REBOOT:
2355 	case NETDEV_GOING_DOWN:
2356 		sk_for_each(sk, &iucv_sk_list.head) {
2357 			iucv = iucv_sk(sk);
2358 			if ((iucv->hs_dev == event_dev) &&
2359 			    (sk->sk_state == IUCV_CONNECTED)) {
2360 				if (event == NETDEV_GOING_DOWN)
2361 					iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2362 				sk->sk_state = IUCV_DISCONN;
2363 				sk->sk_state_change(sk);
2364 			}
2365 		}
2366 		break;
2367 	case NETDEV_DOWN:
2368 	case NETDEV_UNREGISTER:
2369 	default:
2370 		break;
2371 	}
2372 	return NOTIFY_DONE;
2373 }
2374 
2375 static struct notifier_block afiucv_netdev_notifier = {
2376 	.notifier_call = afiucv_netdev_event,
2377 };
2378 
2379 static const struct proto_ops iucv_sock_ops = {
2380 	.family		= PF_IUCV,
2381 	.owner		= THIS_MODULE,
2382 	.release	= iucv_sock_release,
2383 	.bind		= iucv_sock_bind,
2384 	.connect	= iucv_sock_connect,
2385 	.listen		= iucv_sock_listen,
2386 	.accept		= iucv_sock_accept,
2387 	.getname	= iucv_sock_getname,
2388 	.sendmsg	= iucv_sock_sendmsg,
2389 	.recvmsg	= iucv_sock_recvmsg,
2390 	.poll		= iucv_sock_poll,
2391 	.ioctl		= sock_no_ioctl,
2392 	.mmap		= sock_no_mmap,
2393 	.socketpair	= sock_no_socketpair,
2394 	.shutdown	= iucv_sock_shutdown,
2395 	.setsockopt	= iucv_sock_setsockopt,
2396 	.getsockopt	= iucv_sock_getsockopt,
2397 };
2398 
2399 static const struct net_proto_family iucv_sock_family_ops = {
2400 	.family	= AF_IUCV,
2401 	.owner	= THIS_MODULE,
2402 	.create	= iucv_sock_create,
2403 };
2404 
2405 static struct packet_type iucv_packet_type = {
2406 	.type = cpu_to_be16(ETH_P_AF_IUCV),
2407 	.func = afiucv_hs_rcv,
2408 };
2409 
2410 static int afiucv_iucv_init(void)
2411 {
2412 	int err;
2413 
2414 	err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2415 	if (err)
2416 		goto out;
2417 	/* establish dummy device */
2418 	af_iucv_driver.bus = pr_iucv->bus;
2419 	err = driver_register(&af_iucv_driver);
2420 	if (err)
2421 		goto out_iucv;
2422 	af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2423 	if (!af_iucv_dev) {
2424 		err = -ENOMEM;
2425 		goto out_driver;
2426 	}
2427 	dev_set_name(af_iucv_dev, "af_iucv");
2428 	af_iucv_dev->bus = pr_iucv->bus;
2429 	af_iucv_dev->parent = pr_iucv->root;
2430 	af_iucv_dev->release = (void (*)(struct device *))kfree;
2431 	af_iucv_dev->driver = &af_iucv_driver;
2432 	err = device_register(af_iucv_dev);
2433 	if (err)
2434 		goto out_iucv_dev;
2435 	return 0;
2436 
2437 out_iucv_dev:
2438 	put_device(af_iucv_dev);
2439 out_driver:
2440 	driver_unregister(&af_iucv_driver);
2441 out_iucv:
2442 	pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2443 out:
2444 	return err;
2445 }
2446 
2447 static void afiucv_iucv_exit(void)
2448 {
2449 	device_unregister(af_iucv_dev);
2450 	driver_unregister(&af_iucv_driver);
2451 	pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2452 }
2453 
2454 static int __init afiucv_init(void)
2455 {
2456 	int err;
2457 
2458 	if (MACHINE_IS_VM) {
2459 		cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2460 		if (unlikely(err)) {
2461 			WARN_ON(err);
2462 			err = -EPROTONOSUPPORT;
2463 			goto out;
2464 		}
2465 
2466 		pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2467 		if (!pr_iucv) {
2468 			printk(KERN_WARNING "iucv_if lookup failed\n");
2469 			memset(&iucv_userid, 0, sizeof(iucv_userid));
2470 		}
2471 	} else {
2472 		memset(&iucv_userid, 0, sizeof(iucv_userid));
2473 		pr_iucv = NULL;
2474 	}
2475 
2476 	err = proto_register(&iucv_proto, 0);
2477 	if (err)
2478 		goto out;
2479 	err = sock_register(&iucv_sock_family_ops);
2480 	if (err)
2481 		goto out_proto;
2482 
2483 	if (pr_iucv) {
2484 		err = afiucv_iucv_init();
2485 		if (err)
2486 			goto out_sock;
2487 	}
2488 
2489 	err = register_netdevice_notifier(&afiucv_netdev_notifier);
2490 	if (err)
2491 		goto out_notifier;
2492 
2493 	dev_add_pack(&iucv_packet_type);
2494 	return 0;
2495 
2496 out_notifier:
2497 	if (pr_iucv)
2498 		afiucv_iucv_exit();
2499 out_sock:
2500 	sock_unregister(PF_IUCV);
2501 out_proto:
2502 	proto_unregister(&iucv_proto);
2503 out:
2504 	if (pr_iucv)
2505 		symbol_put(iucv_if);
2506 	return err;
2507 }
2508 
2509 static void __exit afiucv_exit(void)
2510 {
2511 	if (pr_iucv) {
2512 		afiucv_iucv_exit();
2513 		symbol_put(iucv_if);
2514 	}
2515 
2516 	unregister_netdevice_notifier(&afiucv_netdev_notifier);
2517 	dev_remove_pack(&iucv_packet_type);
2518 	sock_unregister(PF_IUCV);
2519 	proto_unregister(&iucv_proto);
2520 }
2521 
2522 module_init(afiucv_init);
2523 module_exit(afiucv_exit);
2524 
2525 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2526 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2527 MODULE_VERSION(VERSION);
2528 MODULE_LICENSE("GPL");
2529 MODULE_ALIAS_NETPROTO(PF_IUCV);
2530