xref: /linux/net/iucv/af_iucv.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  *  IUCV protocol stack for Linux on zSeries
3  *
4  *  Copyright IBM Corp. 2006, 2009
5  *
6  *  Author(s):	Jennifer Hunt <jenhunt@us.ibm.com>
7  *		Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
8  *  PM functions:
9  *		Ursula Braun <ursula.braun@de.ibm.com>
10  */
11 
12 #define KMSG_COMPONENT "af_iucv"
13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
14 
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <linux/list.h>
18 #include <linux/errno.h>
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
21 #include <linux/slab.h>
22 #include <linux/skbuff.h>
23 #include <linux/init.h>
24 #include <linux/poll.h>
25 #include <net/sock.h>
26 #include <asm/ebcdic.h>
27 #include <asm/cpcmd.h>
28 #include <linux/kmod.h>
29 
30 #include <net/iucv/af_iucv.h>
31 
32 #define VERSION "1.2"
33 
34 static char iucv_userid[80];
35 
36 static const struct proto_ops iucv_sock_ops;
37 
38 static struct proto iucv_proto = {
39 	.name		= "AF_IUCV",
40 	.owner		= THIS_MODULE,
41 	.obj_size	= sizeof(struct iucv_sock),
42 };
43 
44 static struct iucv_interface *pr_iucv;
45 
46 /* special AF_IUCV IPRM messages */
47 static const u8 iprm_shutdown[8] =
48 	{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
49 
50 #define TRGCLS_SIZE	(sizeof(((struct iucv_message *)0)->class))
51 
52 /* macros to set/get socket control buffer at correct offset */
53 #define CB_TAG(skb)	((skb)->cb)		/* iucv message tag */
54 #define CB_TAG_LEN	(sizeof(((struct iucv_message *) 0)->tag))
55 #define CB_TRGCLS(skb)	((skb)->cb + CB_TAG_LEN) /* iucv msg target class */
56 #define CB_TRGCLS_LEN	(TRGCLS_SIZE)
57 
58 #define __iucv_sock_wait(sk, condition, timeo, ret)			\
59 do {									\
60 	DEFINE_WAIT(__wait);						\
61 	long __timeo = timeo;						\
62 	ret = 0;							\
63 	prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE);	\
64 	while (!(condition)) {						\
65 		if (!__timeo) {						\
66 			ret = -EAGAIN;					\
67 			break;						\
68 		}							\
69 		if (signal_pending(current)) {				\
70 			ret = sock_intr_errno(__timeo);			\
71 			break;						\
72 		}							\
73 		release_sock(sk);					\
74 		__timeo = schedule_timeout(__timeo);			\
75 		lock_sock(sk);						\
76 		ret = sock_error(sk);					\
77 		if (ret)						\
78 			break;						\
79 	}								\
80 	finish_wait(sk_sleep(sk), &__wait);				\
81 } while (0)
82 
83 #define iucv_sock_wait(sk, condition, timeo)				\
84 ({									\
85 	int __ret = 0;							\
86 	if (!(condition))						\
87 		__iucv_sock_wait(sk, condition, timeo, __ret);		\
88 	__ret;								\
89 })
90 
91 static void iucv_sock_kill(struct sock *sk);
92 static void iucv_sock_close(struct sock *sk);
93 
94 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
95 	struct packet_type *pt, struct net_device *orig_dev);
96 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
97 		   struct sk_buff *skb, u8 flags);
98 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
99 
100 /* Call Back functions */
101 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
102 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
103 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
104 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
105 				 u8 ipuser[16]);
106 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
107 static void iucv_callback_shutdown(struct iucv_path *, u8 ipuser[16]);
108 
109 static struct iucv_sock_list iucv_sk_list = {
110 	.lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
111 	.autobind_name = ATOMIC_INIT(0)
112 };
113 
114 static struct iucv_handler af_iucv_handler = {
115 	.path_pending	  = iucv_callback_connreq,
116 	.path_complete	  = iucv_callback_connack,
117 	.path_severed	  = iucv_callback_connrej,
118 	.message_pending  = iucv_callback_rx,
119 	.message_complete = iucv_callback_txdone,
120 	.path_quiesced	  = iucv_callback_shutdown,
121 };
122 
123 static inline void high_nmcpy(unsigned char *dst, char *src)
124 {
125        memcpy(dst, src, 8);
126 }
127 
128 static inline void low_nmcpy(unsigned char *dst, char *src)
129 {
130        memcpy(&dst[8], src, 8);
131 }
132 
133 static int afiucv_pm_prepare(struct device *dev)
134 {
135 #ifdef CONFIG_PM_DEBUG
136 	printk(KERN_WARNING "afiucv_pm_prepare\n");
137 #endif
138 	return 0;
139 }
140 
141 static void afiucv_pm_complete(struct device *dev)
142 {
143 #ifdef CONFIG_PM_DEBUG
144 	printk(KERN_WARNING "afiucv_pm_complete\n");
145 #endif
146 }
147 
148 /**
149  * afiucv_pm_freeze() - Freeze PM callback
150  * @dev:	AFIUCV dummy device
151  *
152  * Sever all established IUCV communication pathes
153  */
154 static int afiucv_pm_freeze(struct device *dev)
155 {
156 	struct iucv_sock *iucv;
157 	struct sock *sk;
158 	struct hlist_node *node;
159 	int err = 0;
160 
161 #ifdef CONFIG_PM_DEBUG
162 	printk(KERN_WARNING "afiucv_pm_freeze\n");
163 #endif
164 	read_lock(&iucv_sk_list.lock);
165 	sk_for_each(sk, node, &iucv_sk_list.head) {
166 		iucv = iucv_sk(sk);
167 		skb_queue_purge(&iucv->send_skb_q);
168 		skb_queue_purge(&iucv->backlog_skb_q);
169 		switch (sk->sk_state) {
170 		case IUCV_SEVERED:
171 		case IUCV_DISCONN:
172 		case IUCV_CLOSING:
173 		case IUCV_CONNECTED:
174 			if (iucv->path) {
175 				err = pr_iucv->path_sever(iucv->path, NULL);
176 				iucv_path_free(iucv->path);
177 				iucv->path = NULL;
178 			}
179 			break;
180 		case IUCV_OPEN:
181 		case IUCV_BOUND:
182 		case IUCV_LISTEN:
183 		case IUCV_CLOSED:
184 		default:
185 			break;
186 		}
187 	}
188 	read_unlock(&iucv_sk_list.lock);
189 	return err;
190 }
191 
192 /**
193  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
194  * @dev:	AFIUCV dummy device
195  *
196  * socket clean up after freeze
197  */
198 static int afiucv_pm_restore_thaw(struct device *dev)
199 {
200 	struct sock *sk;
201 	struct hlist_node *node;
202 
203 #ifdef CONFIG_PM_DEBUG
204 	printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
205 #endif
206 	read_lock(&iucv_sk_list.lock);
207 	sk_for_each(sk, node, &iucv_sk_list.head) {
208 		switch (sk->sk_state) {
209 		case IUCV_CONNECTED:
210 			sk->sk_err = EPIPE;
211 			sk->sk_state = IUCV_DISCONN;
212 			sk->sk_state_change(sk);
213 			break;
214 		case IUCV_DISCONN:
215 		case IUCV_SEVERED:
216 		case IUCV_CLOSING:
217 		case IUCV_LISTEN:
218 		case IUCV_BOUND:
219 		case IUCV_OPEN:
220 		default:
221 			break;
222 		}
223 	}
224 	read_unlock(&iucv_sk_list.lock);
225 	return 0;
226 }
227 
228 static const struct dev_pm_ops afiucv_pm_ops = {
229 	.prepare = afiucv_pm_prepare,
230 	.complete = afiucv_pm_complete,
231 	.freeze = afiucv_pm_freeze,
232 	.thaw = afiucv_pm_restore_thaw,
233 	.restore = afiucv_pm_restore_thaw,
234 };
235 
236 static struct device_driver af_iucv_driver = {
237 	.owner = THIS_MODULE,
238 	.name = "afiucv",
239 	.bus  = NULL,
240 	.pm   = &afiucv_pm_ops,
241 };
242 
243 /* dummy device used as trigger for PM functions */
244 static struct device *af_iucv_dev;
245 
246 /**
247  * iucv_msg_length() - Returns the length of an iucv message.
248  * @msg:	Pointer to struct iucv_message, MUST NOT be NULL
249  *
250  * The function returns the length of the specified iucv message @msg of data
251  * stored in a buffer and of data stored in the parameter list (PRMDATA).
252  *
253  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
254  * data:
255  *	PRMDATA[0..6]	socket data (max 7 bytes);
256  *	PRMDATA[7]	socket data length value (len is 0xff - PRMDATA[7])
257  *
258  * The socket data length is computed by subtracting the socket data length
259  * value from 0xFF.
260  * If the socket data len is greater 7, then PRMDATA can be used for special
261  * notifications (see iucv_sock_shutdown); and further,
262  * if the socket data len is > 7, the function returns 8.
263  *
264  * Use this function to allocate socket buffers to store iucv message data.
265  */
266 static inline size_t iucv_msg_length(struct iucv_message *msg)
267 {
268 	size_t datalen;
269 
270 	if (msg->flags & IUCV_IPRMDATA) {
271 		datalen = 0xff - msg->rmmsg[7];
272 		return (datalen < 8) ? datalen : 8;
273 	}
274 	return msg->length;
275 }
276 
277 /**
278  * iucv_sock_in_state() - check for specific states
279  * @sk:		sock structure
280  * @state:	first iucv sk state
281  * @state:	second iucv sk state
282  *
283  * Returns true if the socket in either in the first or second state.
284  */
285 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
286 {
287 	return (sk->sk_state == state || sk->sk_state == state2);
288 }
289 
290 /**
291  * iucv_below_msglim() - function to check if messages can be sent
292  * @sk:		sock structure
293  *
294  * Returns true if the send queue length is lower than the message limit.
295  * Always returns true if the socket is not connected (no iucv path for
296  * checking the message limit).
297  */
298 static inline int iucv_below_msglim(struct sock *sk)
299 {
300 	struct iucv_sock *iucv = iucv_sk(sk);
301 
302 	if (sk->sk_state != IUCV_CONNECTED)
303 		return 1;
304 	if (iucv->transport == AF_IUCV_TRANS_IUCV)
305 		return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
306 	else
307 		return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
308 			(atomic_read(&iucv->pendings) <= 0));
309 }
310 
311 /**
312  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
313  */
314 static void iucv_sock_wake_msglim(struct sock *sk)
315 {
316 	struct socket_wq *wq;
317 
318 	rcu_read_lock();
319 	wq = rcu_dereference(sk->sk_wq);
320 	if (wq_has_sleeper(wq))
321 		wake_up_interruptible_all(&wq->wait);
322 	sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
323 	rcu_read_unlock();
324 }
325 
326 /**
327  * afiucv_hs_send() - send a message through HiperSockets transport
328  */
329 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
330 		   struct sk_buff *skb, u8 flags)
331 {
332 	struct net *net = sock_net(sock);
333 	struct iucv_sock *iucv = iucv_sk(sock);
334 	struct af_iucv_trans_hdr *phs_hdr;
335 	struct sk_buff *nskb;
336 	int err, confirm_recv = 0;
337 
338 	memset(skb->head, 0, ETH_HLEN);
339 	phs_hdr = (struct af_iucv_trans_hdr *)skb_push(skb,
340 					sizeof(struct af_iucv_trans_hdr));
341 	skb_reset_mac_header(skb);
342 	skb_reset_network_header(skb);
343 	skb_push(skb, ETH_HLEN);
344 	skb_reset_mac_header(skb);
345 	memset(phs_hdr, 0, sizeof(struct af_iucv_trans_hdr));
346 
347 	phs_hdr->magic = ETH_P_AF_IUCV;
348 	phs_hdr->version = 1;
349 	phs_hdr->flags = flags;
350 	if (flags == AF_IUCV_FLAG_SYN)
351 		phs_hdr->window = iucv->msglimit;
352 	else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
353 		confirm_recv = atomic_read(&iucv->msg_recv);
354 		phs_hdr->window = confirm_recv;
355 		if (confirm_recv)
356 			phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
357 	}
358 	memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
359 	memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
360 	memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
361 	memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
362 	ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
363 	ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
364 	ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
365 	ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
366 	if (imsg)
367 		memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
368 
369 	rcu_read_lock();
370 	skb->dev = dev_get_by_index_rcu(net, sock->sk_bound_dev_if);
371 	rcu_read_unlock();
372 	if (!skb->dev)
373 		return -ENODEV;
374 	if (!(skb->dev->flags & IFF_UP))
375 		return -ENETDOWN;
376 	if (skb->len > skb->dev->mtu) {
377 		if (sock->sk_type == SOCK_SEQPACKET)
378 			return -EMSGSIZE;
379 		else
380 			skb_trim(skb, skb->dev->mtu);
381 	}
382 	skb->protocol = ETH_P_AF_IUCV;
383 	skb_shinfo(skb)->tx_flags |= SKBTX_DRV_NEEDS_SK_REF;
384 	nskb = skb_clone(skb, GFP_ATOMIC);
385 	if (!nskb)
386 		return -ENOMEM;
387 	skb_queue_tail(&iucv->send_skb_q, nskb);
388 	err = dev_queue_xmit(skb);
389 	if (err) {
390 		skb_unlink(nskb, &iucv->send_skb_q);
391 		kfree_skb(nskb);
392 	} else {
393 		atomic_sub(confirm_recv, &iucv->msg_recv);
394 		WARN_ON(atomic_read(&iucv->msg_recv) < 0);
395 	}
396 	return err;
397 }
398 
399 /* Timers */
400 static void iucv_sock_timeout(unsigned long arg)
401 {
402 	struct sock *sk = (struct sock *)arg;
403 
404 	bh_lock_sock(sk);
405 	sk->sk_err = ETIMEDOUT;
406 	sk->sk_state_change(sk);
407 	bh_unlock_sock(sk);
408 
409 	iucv_sock_kill(sk);
410 	sock_put(sk);
411 }
412 
413 static void iucv_sock_clear_timer(struct sock *sk)
414 {
415 	sk_stop_timer(sk, &sk->sk_timer);
416 }
417 
418 static struct sock *__iucv_get_sock_by_name(char *nm)
419 {
420 	struct sock *sk;
421 	struct hlist_node *node;
422 
423 	sk_for_each(sk, node, &iucv_sk_list.head)
424 		if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
425 			return sk;
426 
427 	return NULL;
428 }
429 
430 static void iucv_sock_destruct(struct sock *sk)
431 {
432 	skb_queue_purge(&sk->sk_receive_queue);
433 	skb_queue_purge(&sk->sk_write_queue);
434 }
435 
436 /* Cleanup Listen */
437 static void iucv_sock_cleanup_listen(struct sock *parent)
438 {
439 	struct sock *sk;
440 
441 	/* Close non-accepted connections */
442 	while ((sk = iucv_accept_dequeue(parent, NULL))) {
443 		iucv_sock_close(sk);
444 		iucv_sock_kill(sk);
445 	}
446 
447 	parent->sk_state = IUCV_CLOSED;
448 }
449 
450 /* Kill socket (only if zapped and orphaned) */
451 static void iucv_sock_kill(struct sock *sk)
452 {
453 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
454 		return;
455 
456 	iucv_sock_unlink(&iucv_sk_list, sk);
457 	sock_set_flag(sk, SOCK_DEAD);
458 	sock_put(sk);
459 }
460 
461 /* Close an IUCV socket */
462 static void iucv_sock_close(struct sock *sk)
463 {
464 	unsigned char user_data[16];
465 	struct iucv_sock *iucv = iucv_sk(sk);
466 	unsigned long timeo;
467 	int err, blen;
468 	struct sk_buff *skb;
469 
470 	iucv_sock_clear_timer(sk);
471 	lock_sock(sk);
472 
473 	switch (sk->sk_state) {
474 	case IUCV_LISTEN:
475 		iucv_sock_cleanup_listen(sk);
476 		break;
477 
478 	case IUCV_CONNECTED:
479 		if (iucv->transport == AF_IUCV_TRANS_HIPER) {
480 			/* send fin */
481 			blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
482 			skb = sock_alloc_send_skb(sk, blen, 1, &err);
483 			if (skb) {
484 				skb_reserve(skb,
485 					sizeof(struct af_iucv_trans_hdr) +
486 					ETH_HLEN);
487 				err = afiucv_hs_send(NULL, sk, skb,
488 						     AF_IUCV_FLAG_FIN);
489 			}
490 			sk->sk_state = IUCV_DISCONN;
491 			sk->sk_state_change(sk);
492 		}
493 	case IUCV_DISCONN:
494 		sk->sk_state = IUCV_CLOSING;
495 		sk->sk_state_change(sk);
496 
497 		if (!skb_queue_empty(&iucv->send_skb_q)) {
498 			if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
499 				timeo = sk->sk_lingertime;
500 			else
501 				timeo = IUCV_DISCONN_TIMEOUT;
502 			iucv_sock_wait(sk,
503 					iucv_sock_in_state(sk, IUCV_CLOSED, 0),
504 					timeo);
505 		}
506 
507 	case IUCV_CLOSING:   /* fall through */
508 		sk->sk_state = IUCV_CLOSED;
509 		sk->sk_state_change(sk);
510 
511 		if (iucv->path) {
512 			low_nmcpy(user_data, iucv->src_name);
513 			high_nmcpy(user_data, iucv->dst_name);
514 			ASCEBC(user_data, sizeof(user_data));
515 			pr_iucv->path_sever(iucv->path, user_data);
516 			iucv_path_free(iucv->path);
517 			iucv->path = NULL;
518 		}
519 
520 		sk->sk_err = ECONNRESET;
521 		sk->sk_state_change(sk);
522 
523 		skb_queue_purge(&iucv->send_skb_q);
524 		skb_queue_purge(&iucv->backlog_skb_q);
525 		break;
526 
527 	default:
528 		/* nothing to do here */
529 		break;
530 	}
531 
532 	/* mark socket for deletion by iucv_sock_kill() */
533 	sock_set_flag(sk, SOCK_ZAPPED);
534 
535 	release_sock(sk);
536 }
537 
538 static void iucv_sock_init(struct sock *sk, struct sock *parent)
539 {
540 	if (parent)
541 		sk->sk_type = parent->sk_type;
542 }
543 
544 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
545 {
546 	struct sock *sk;
547 	struct iucv_sock *iucv;
548 
549 	sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
550 	if (!sk)
551 		return NULL;
552 	iucv = iucv_sk(sk);
553 
554 	sock_init_data(sock, sk);
555 	INIT_LIST_HEAD(&iucv->accept_q);
556 	spin_lock_init(&iucv->accept_q_lock);
557 	skb_queue_head_init(&iucv->send_skb_q);
558 	INIT_LIST_HEAD(&iucv->message_q.list);
559 	spin_lock_init(&iucv->message_q.lock);
560 	skb_queue_head_init(&iucv->backlog_skb_q);
561 	iucv->send_tag = 0;
562 	atomic_set(&iucv->pendings, 0);
563 	iucv->flags = 0;
564 	iucv->msglimit = 0;
565 	atomic_set(&iucv->msg_sent, 0);
566 	atomic_set(&iucv->msg_recv, 0);
567 	iucv->path = NULL;
568 	iucv->sk_txnotify = afiucv_hs_callback_txnotify;
569 	memset(&iucv->src_user_id , 0, 32);
570 	if (pr_iucv)
571 		iucv->transport = AF_IUCV_TRANS_IUCV;
572 	else
573 		iucv->transport = AF_IUCV_TRANS_HIPER;
574 
575 	sk->sk_destruct = iucv_sock_destruct;
576 	sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
577 	sk->sk_allocation = GFP_DMA;
578 
579 	sock_reset_flag(sk, SOCK_ZAPPED);
580 
581 	sk->sk_protocol = proto;
582 	sk->sk_state	= IUCV_OPEN;
583 
584 	setup_timer(&sk->sk_timer, iucv_sock_timeout, (unsigned long)sk);
585 
586 	iucv_sock_link(&iucv_sk_list, sk);
587 	return sk;
588 }
589 
590 /* Create an IUCV socket */
591 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
592 			    int kern)
593 {
594 	struct sock *sk;
595 
596 	if (protocol && protocol != PF_IUCV)
597 		return -EPROTONOSUPPORT;
598 
599 	sock->state = SS_UNCONNECTED;
600 
601 	switch (sock->type) {
602 	case SOCK_STREAM:
603 		sock->ops = &iucv_sock_ops;
604 		break;
605 	case SOCK_SEQPACKET:
606 		/* currently, proto ops can handle both sk types */
607 		sock->ops = &iucv_sock_ops;
608 		break;
609 	default:
610 		return -ESOCKTNOSUPPORT;
611 	}
612 
613 	sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
614 	if (!sk)
615 		return -ENOMEM;
616 
617 	iucv_sock_init(sk, NULL);
618 
619 	return 0;
620 }
621 
622 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
623 {
624 	write_lock_bh(&l->lock);
625 	sk_add_node(sk, &l->head);
626 	write_unlock_bh(&l->lock);
627 }
628 
629 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
630 {
631 	write_lock_bh(&l->lock);
632 	sk_del_node_init(sk);
633 	write_unlock_bh(&l->lock);
634 }
635 
636 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
637 {
638 	unsigned long flags;
639 	struct iucv_sock *par = iucv_sk(parent);
640 
641 	sock_hold(sk);
642 	spin_lock_irqsave(&par->accept_q_lock, flags);
643 	list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
644 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
645 	iucv_sk(sk)->parent = parent;
646 	sk_acceptq_added(parent);
647 }
648 
649 void iucv_accept_unlink(struct sock *sk)
650 {
651 	unsigned long flags;
652 	struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
653 
654 	spin_lock_irqsave(&par->accept_q_lock, flags);
655 	list_del_init(&iucv_sk(sk)->accept_q);
656 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
657 	sk_acceptq_removed(iucv_sk(sk)->parent);
658 	iucv_sk(sk)->parent = NULL;
659 	sock_put(sk);
660 }
661 
662 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
663 {
664 	struct iucv_sock *isk, *n;
665 	struct sock *sk;
666 
667 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
668 		sk = (struct sock *) isk;
669 		lock_sock(sk);
670 
671 		if (sk->sk_state == IUCV_CLOSED) {
672 			iucv_accept_unlink(sk);
673 			release_sock(sk);
674 			continue;
675 		}
676 
677 		if (sk->sk_state == IUCV_CONNECTED ||
678 		    sk->sk_state == IUCV_SEVERED ||
679 		    sk->sk_state == IUCV_DISCONN ||	/* due to PM restore */
680 		    !newsock) {
681 			iucv_accept_unlink(sk);
682 			if (newsock)
683 				sock_graft(sk, newsock);
684 
685 			if (sk->sk_state == IUCV_SEVERED)
686 				sk->sk_state = IUCV_DISCONN;
687 
688 			release_sock(sk);
689 			return sk;
690 		}
691 
692 		release_sock(sk);
693 	}
694 	return NULL;
695 }
696 
697 /* Bind an unbound socket */
698 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
699 			  int addr_len)
700 {
701 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
702 	struct sock *sk = sock->sk;
703 	struct iucv_sock *iucv;
704 	int err = 0;
705 	struct net_device *dev;
706 	char uid[9];
707 
708 	/* Verify the input sockaddr */
709 	if (!addr || addr->sa_family != AF_IUCV)
710 		return -EINVAL;
711 
712 	lock_sock(sk);
713 	if (sk->sk_state != IUCV_OPEN) {
714 		err = -EBADFD;
715 		goto done;
716 	}
717 
718 	write_lock_bh(&iucv_sk_list.lock);
719 
720 	iucv = iucv_sk(sk);
721 	if (__iucv_get_sock_by_name(sa->siucv_name)) {
722 		err = -EADDRINUSE;
723 		goto done_unlock;
724 	}
725 	if (iucv->path)
726 		goto done_unlock;
727 
728 	/* Bind the socket */
729 
730 	if (pr_iucv)
731 		if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
732 			goto vm_bind; /* VM IUCV transport */
733 
734 	/* try hiper transport */
735 	memcpy(uid, sa->siucv_user_id, sizeof(uid));
736 	ASCEBC(uid, 8);
737 	rcu_read_lock();
738 	for_each_netdev_rcu(&init_net, dev) {
739 		if (!memcmp(dev->perm_addr, uid, 8)) {
740 			memcpy(iucv->src_name, sa->siucv_name, 8);
741 			memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
742 			sock->sk->sk_bound_dev_if = dev->ifindex;
743 			sk->sk_state = IUCV_BOUND;
744 			iucv->transport = AF_IUCV_TRANS_HIPER;
745 			if (!iucv->msglimit)
746 				iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
747 			rcu_read_unlock();
748 			goto done_unlock;
749 		}
750 	}
751 	rcu_read_unlock();
752 vm_bind:
753 	if (pr_iucv) {
754 		/* use local userid for backward compat */
755 		memcpy(iucv->src_name, sa->siucv_name, 8);
756 		memcpy(iucv->src_user_id, iucv_userid, 8);
757 		sk->sk_state = IUCV_BOUND;
758 		iucv->transport = AF_IUCV_TRANS_IUCV;
759 		if (!iucv->msglimit)
760 			iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
761 		goto done_unlock;
762 	}
763 	/* found no dev to bind */
764 	err = -ENODEV;
765 done_unlock:
766 	/* Release the socket list lock */
767 	write_unlock_bh(&iucv_sk_list.lock);
768 done:
769 	release_sock(sk);
770 	return err;
771 }
772 
773 /* Automatically bind an unbound socket */
774 static int iucv_sock_autobind(struct sock *sk)
775 {
776 	struct iucv_sock *iucv = iucv_sk(sk);
777 	char query_buffer[80];
778 	char name[12];
779 	int err = 0;
780 
781 	/* Set the userid and name */
782 	cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
783 	if (unlikely(err))
784 		return -EPROTO;
785 
786 	memcpy(iucv->src_user_id, query_buffer, 8);
787 
788 	write_lock_bh(&iucv_sk_list.lock);
789 
790 	sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
791 	while (__iucv_get_sock_by_name(name)) {
792 		sprintf(name, "%08x",
793 			atomic_inc_return(&iucv_sk_list.autobind_name));
794 	}
795 
796 	write_unlock_bh(&iucv_sk_list.lock);
797 
798 	memcpy(&iucv->src_name, name, 8);
799 
800 	if (!iucv->msglimit)
801 		iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
802 
803 	return err;
804 }
805 
806 static int afiucv_hs_connect(struct socket *sock)
807 {
808 	struct sock *sk = sock->sk;
809 	struct sk_buff *skb;
810 	int blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
811 	int err = 0;
812 
813 	/* send syn */
814 	skb = sock_alloc_send_skb(sk, blen, 1, &err);
815 	if (!skb) {
816 		err = -ENOMEM;
817 		goto done;
818 	}
819 	skb->dev = NULL;
820 	skb_reserve(skb, blen);
821 	err = afiucv_hs_send(NULL, sk, skb, AF_IUCV_FLAG_SYN);
822 done:
823 	return err;
824 }
825 
826 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
827 {
828 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
829 	struct sock *sk = sock->sk;
830 	struct iucv_sock *iucv = iucv_sk(sk);
831 	unsigned char user_data[16];
832 	int err;
833 
834 	high_nmcpy(user_data, sa->siucv_name);
835 	low_nmcpy(user_data, iucv->src_name);
836 	ASCEBC(user_data, sizeof(user_data));
837 
838 	/* Create path. */
839 	iucv->path = iucv_path_alloc(iucv->msglimit,
840 				     IUCV_IPRMDATA, GFP_KERNEL);
841 	if (!iucv->path) {
842 		err = -ENOMEM;
843 		goto done;
844 	}
845 	err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
846 				    sa->siucv_user_id, NULL, user_data,
847 				    sk);
848 	if (err) {
849 		iucv_path_free(iucv->path);
850 		iucv->path = NULL;
851 		switch (err) {
852 		case 0x0b:	/* Target communicator is not logged on */
853 			err = -ENETUNREACH;
854 			break;
855 		case 0x0d:	/* Max connections for this guest exceeded */
856 		case 0x0e:	/* Max connections for target guest exceeded */
857 			err = -EAGAIN;
858 			break;
859 		case 0x0f:	/* Missing IUCV authorization */
860 			err = -EACCES;
861 			break;
862 		default:
863 			err = -ECONNREFUSED;
864 			break;
865 		}
866 	}
867 done:
868 	return err;
869 }
870 
871 /* Connect an unconnected socket */
872 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
873 			     int alen, int flags)
874 {
875 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
876 	struct sock *sk = sock->sk;
877 	struct iucv_sock *iucv = iucv_sk(sk);
878 	int err;
879 
880 	if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
881 		return -EINVAL;
882 
883 	if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
884 		return -EBADFD;
885 
886 	if (sk->sk_state == IUCV_OPEN &&
887 	    iucv->transport == AF_IUCV_TRANS_HIPER)
888 		return -EBADFD; /* explicit bind required */
889 
890 	if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
891 		return -EINVAL;
892 
893 	if (sk->sk_state == IUCV_OPEN) {
894 		err = iucv_sock_autobind(sk);
895 		if (unlikely(err))
896 			return err;
897 	}
898 
899 	lock_sock(sk);
900 
901 	/* Set the destination information */
902 	memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
903 	memcpy(iucv->dst_name, sa->siucv_name, 8);
904 
905 	if (iucv->transport == AF_IUCV_TRANS_HIPER)
906 		err = afiucv_hs_connect(sock);
907 	else
908 		err = afiucv_path_connect(sock, addr);
909 	if (err)
910 		goto done;
911 
912 	if (sk->sk_state != IUCV_CONNECTED)
913 		err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
914 							    IUCV_DISCONN),
915 				     sock_sndtimeo(sk, flags & O_NONBLOCK));
916 
917 	if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
918 		err = -ECONNREFUSED;
919 
920 	if (err && iucv->transport == AF_IUCV_TRANS_IUCV) {
921 		pr_iucv->path_sever(iucv->path, NULL);
922 		iucv_path_free(iucv->path);
923 		iucv->path = NULL;
924 	}
925 
926 done:
927 	release_sock(sk);
928 	return err;
929 }
930 
931 /* Move a socket into listening state. */
932 static int iucv_sock_listen(struct socket *sock, int backlog)
933 {
934 	struct sock *sk = sock->sk;
935 	int err;
936 
937 	lock_sock(sk);
938 
939 	err = -EINVAL;
940 	if (sk->sk_state != IUCV_BOUND)
941 		goto done;
942 
943 	if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
944 		goto done;
945 
946 	sk->sk_max_ack_backlog = backlog;
947 	sk->sk_ack_backlog = 0;
948 	sk->sk_state = IUCV_LISTEN;
949 	err = 0;
950 
951 done:
952 	release_sock(sk);
953 	return err;
954 }
955 
956 /* Accept a pending connection */
957 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
958 			    int flags)
959 {
960 	DECLARE_WAITQUEUE(wait, current);
961 	struct sock *sk = sock->sk, *nsk;
962 	long timeo;
963 	int err = 0;
964 
965 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
966 
967 	if (sk->sk_state != IUCV_LISTEN) {
968 		err = -EBADFD;
969 		goto done;
970 	}
971 
972 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
973 
974 	/* Wait for an incoming connection */
975 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
976 	while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
977 		set_current_state(TASK_INTERRUPTIBLE);
978 		if (!timeo) {
979 			err = -EAGAIN;
980 			break;
981 		}
982 
983 		release_sock(sk);
984 		timeo = schedule_timeout(timeo);
985 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
986 
987 		if (sk->sk_state != IUCV_LISTEN) {
988 			err = -EBADFD;
989 			break;
990 		}
991 
992 		if (signal_pending(current)) {
993 			err = sock_intr_errno(timeo);
994 			break;
995 		}
996 	}
997 
998 	set_current_state(TASK_RUNNING);
999 	remove_wait_queue(sk_sleep(sk), &wait);
1000 
1001 	if (err)
1002 		goto done;
1003 
1004 	newsock->state = SS_CONNECTED;
1005 
1006 done:
1007 	release_sock(sk);
1008 	return err;
1009 }
1010 
1011 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
1012 			     int *len, int peer)
1013 {
1014 	struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
1015 	struct sock *sk = sock->sk;
1016 	struct iucv_sock *iucv = iucv_sk(sk);
1017 
1018 	addr->sa_family = AF_IUCV;
1019 	*len = sizeof(struct sockaddr_iucv);
1020 
1021 	if (peer) {
1022 		memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
1023 		memcpy(siucv->siucv_name, iucv->dst_name, 8);
1024 	} else {
1025 		memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
1026 		memcpy(siucv->siucv_name, iucv->src_name, 8);
1027 	}
1028 	memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
1029 	memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
1030 	memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
1031 
1032 	return 0;
1033 }
1034 
1035 /**
1036  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1037  * @path:	IUCV path
1038  * @msg:	Pointer to a struct iucv_message
1039  * @skb:	The socket data to send, skb->len MUST BE <= 7
1040  *
1041  * Send the socket data in the parameter list in the iucv message
1042  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1043  * list and the socket data len at index 7 (last byte).
1044  * See also iucv_msg_length().
1045  *
1046  * Returns the error code from the iucv_message_send() call.
1047  */
1048 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1049 			  struct sk_buff *skb)
1050 {
1051 	u8 prmdata[8];
1052 
1053 	memcpy(prmdata, (void *) skb->data, skb->len);
1054 	prmdata[7] = 0xff - (u8) skb->len;
1055 	return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1056 				 (void *) prmdata, 8);
1057 }
1058 
1059 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
1060 			     struct msghdr *msg, size_t len)
1061 {
1062 	struct sock *sk = sock->sk;
1063 	struct iucv_sock *iucv = iucv_sk(sk);
1064 	struct sk_buff *skb;
1065 	struct iucv_message txmsg;
1066 	struct cmsghdr *cmsg;
1067 	int cmsg_done;
1068 	long timeo;
1069 	char user_id[9];
1070 	char appl_id[9];
1071 	int err;
1072 	int noblock = msg->msg_flags & MSG_DONTWAIT;
1073 
1074 	err = sock_error(sk);
1075 	if (err)
1076 		return err;
1077 
1078 	if (msg->msg_flags & MSG_OOB)
1079 		return -EOPNOTSUPP;
1080 
1081 	/* SOCK_SEQPACKET: we do not support segmented records */
1082 	if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1083 		return -EOPNOTSUPP;
1084 
1085 	lock_sock(sk);
1086 
1087 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1088 		err = -EPIPE;
1089 		goto out;
1090 	}
1091 
1092 	/* Return if the socket is not in connected state */
1093 	if (sk->sk_state != IUCV_CONNECTED) {
1094 		err = -ENOTCONN;
1095 		goto out;
1096 	}
1097 
1098 	/* initialize defaults */
1099 	cmsg_done   = 0;	/* check for duplicate headers */
1100 	txmsg.class = 0;
1101 
1102 	/* iterate over control messages */
1103 	for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
1104 		cmsg = CMSG_NXTHDR(msg, cmsg)) {
1105 
1106 		if (!CMSG_OK(msg, cmsg)) {
1107 			err = -EINVAL;
1108 			goto out;
1109 		}
1110 
1111 		if (cmsg->cmsg_level != SOL_IUCV)
1112 			continue;
1113 
1114 		if (cmsg->cmsg_type & cmsg_done) {
1115 			err = -EINVAL;
1116 			goto out;
1117 		}
1118 		cmsg_done |= cmsg->cmsg_type;
1119 
1120 		switch (cmsg->cmsg_type) {
1121 		case SCM_IUCV_TRGCLS:
1122 			if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1123 				err = -EINVAL;
1124 				goto out;
1125 			}
1126 
1127 			/* set iucv message target class */
1128 			memcpy(&txmsg.class,
1129 				(void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1130 
1131 			break;
1132 
1133 		default:
1134 			err = -EINVAL;
1135 			goto out;
1136 			break;
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 		skb = sock_alloc_send_skb(sk,
1146 			len + sizeof(struct af_iucv_trans_hdr) + ETH_HLEN,
1147 			noblock, &err);
1148 	else
1149 		skb = sock_alloc_send_skb(sk, len, noblock, &err);
1150 	if (!skb)
1151 		goto out;
1152 	if (iucv->transport == AF_IUCV_TRANS_HIPER)
1153 		skb_reserve(skb, sizeof(struct af_iucv_trans_hdr) + ETH_HLEN);
1154 	if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
1155 		err = -EFAULT;
1156 		goto fail;
1157 	}
1158 
1159 	/* wait if outstanding messages for iucv path has reached */
1160 	timeo = sock_sndtimeo(sk, noblock);
1161 	err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1162 	if (err)
1163 		goto fail;
1164 
1165 	/* return -ECONNRESET if the socket is no longer connected */
1166 	if (sk->sk_state != IUCV_CONNECTED) {
1167 		err = -ECONNRESET;
1168 		goto fail;
1169 	}
1170 
1171 	/* increment and save iucv message tag for msg_completion cbk */
1172 	txmsg.tag = iucv->send_tag++;
1173 	memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);
1174 	if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1175 		atomic_inc(&iucv->msg_sent);
1176 		err = afiucv_hs_send(&txmsg, sk, skb, 0);
1177 		if (err) {
1178 			atomic_dec(&iucv->msg_sent);
1179 			goto fail;
1180 		}
1181 		goto release;
1182 	}
1183 	skb_queue_tail(&iucv->send_skb_q, skb);
1184 
1185 	if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
1186 	      && skb->len <= 7) {
1187 		err = iucv_send_iprm(iucv->path, &txmsg, skb);
1188 
1189 		/* on success: there is no message_complete callback
1190 		 * for an IPRMDATA msg; remove skb from send queue */
1191 		if (err == 0) {
1192 			skb_unlink(skb, &iucv->send_skb_q);
1193 			kfree_skb(skb);
1194 		}
1195 
1196 		/* this error should never happen since the
1197 		 * IUCV_IPRMDATA path flag is set... sever path */
1198 		if (err == 0x15) {
1199 			pr_iucv->path_sever(iucv->path, NULL);
1200 			skb_unlink(skb, &iucv->send_skb_q);
1201 			err = -EPIPE;
1202 			goto fail;
1203 		}
1204 	} else
1205 		err = pr_iucv->message_send(iucv->path, &txmsg, 0, 0,
1206 					(void *) skb->data, skb->len);
1207 	if (err) {
1208 		if (err == 3) {
1209 			user_id[8] = 0;
1210 			memcpy(user_id, iucv->dst_user_id, 8);
1211 			appl_id[8] = 0;
1212 			memcpy(appl_id, iucv->dst_name, 8);
1213 			pr_err("Application %s on z/VM guest %s"
1214 				" exceeds message limit\n",
1215 				appl_id, user_id);
1216 			err = -EAGAIN;
1217 		} else
1218 			err = -EPIPE;
1219 		skb_unlink(skb, &iucv->send_skb_q);
1220 		goto fail;
1221 	}
1222 
1223 release:
1224 	release_sock(sk);
1225 	return len;
1226 
1227 fail:
1228 	kfree_skb(skb);
1229 out:
1230 	release_sock(sk);
1231 	return err;
1232 }
1233 
1234 /* iucv_fragment_skb() - Fragment a single IUCV message into multiple skb's
1235  *
1236  * Locking: must be called with message_q.lock held
1237  */
1238 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
1239 {
1240 	int dataleft, size, copied = 0;
1241 	struct sk_buff *nskb;
1242 
1243 	dataleft = len;
1244 	while (dataleft) {
1245 		if (dataleft >= sk->sk_rcvbuf / 4)
1246 			size = sk->sk_rcvbuf / 4;
1247 		else
1248 			size = dataleft;
1249 
1250 		nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
1251 		if (!nskb)
1252 			return -ENOMEM;
1253 
1254 		/* copy target class to control buffer of new skb */
1255 		memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);
1256 
1257 		/* copy data fragment */
1258 		memcpy(nskb->data, skb->data + copied, size);
1259 		copied += size;
1260 		dataleft -= size;
1261 
1262 		skb_reset_transport_header(nskb);
1263 		skb_reset_network_header(nskb);
1264 		nskb->len = size;
1265 
1266 		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
1267 	}
1268 
1269 	return 0;
1270 }
1271 
1272 /* iucv_process_message() - Receive a single outstanding IUCV message
1273  *
1274  * Locking: must be called with message_q.lock held
1275  */
1276 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1277 				 struct iucv_path *path,
1278 				 struct iucv_message *msg)
1279 {
1280 	int rc;
1281 	unsigned int len;
1282 
1283 	len = iucv_msg_length(msg);
1284 
1285 	/* store msg target class in the second 4 bytes of skb ctrl buffer */
1286 	/* Note: the first 4 bytes are reserved for msg tag */
1287 	memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);
1288 
1289 	/* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1290 	if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1291 		if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1292 			skb->data = NULL;
1293 			skb->len = 0;
1294 		}
1295 	} else {
1296 		rc = pr_iucv->message_receive(path, msg,
1297 					      msg->flags & IUCV_IPRMDATA,
1298 					      skb->data, len, NULL);
1299 		if (rc) {
1300 			kfree_skb(skb);
1301 			return;
1302 		}
1303 		/* we need to fragment iucv messages for SOCK_STREAM only;
1304 		 * for SOCK_SEQPACKET, it is only relevant if we support
1305 		 * record segmentation using MSG_EOR (see also recvmsg()) */
1306 		if (sk->sk_type == SOCK_STREAM &&
1307 		    skb->truesize >= sk->sk_rcvbuf / 4) {
1308 			rc = iucv_fragment_skb(sk, skb, len);
1309 			kfree_skb(skb);
1310 			skb = NULL;
1311 			if (rc) {
1312 				pr_iucv->path_sever(path, NULL);
1313 				return;
1314 			}
1315 			skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
1316 		} else {
1317 			skb_reset_transport_header(skb);
1318 			skb_reset_network_header(skb);
1319 			skb->len = len;
1320 		}
1321 	}
1322 
1323 	if (sock_queue_rcv_skb(sk, skb))
1324 		skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1325 }
1326 
1327 /* iucv_process_message_q() - Process outstanding IUCV messages
1328  *
1329  * Locking: must be called with message_q.lock held
1330  */
1331 static void iucv_process_message_q(struct sock *sk)
1332 {
1333 	struct iucv_sock *iucv = iucv_sk(sk);
1334 	struct sk_buff *skb;
1335 	struct sock_msg_q *p, *n;
1336 
1337 	list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1338 		skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1339 		if (!skb)
1340 			break;
1341 		iucv_process_message(sk, skb, p->path, &p->msg);
1342 		list_del(&p->list);
1343 		kfree(p);
1344 		if (!skb_queue_empty(&iucv->backlog_skb_q))
1345 			break;
1346 	}
1347 }
1348 
1349 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1350 			     struct msghdr *msg, size_t len, int flags)
1351 {
1352 	int noblock = flags & MSG_DONTWAIT;
1353 	struct sock *sk = sock->sk;
1354 	struct iucv_sock *iucv = iucv_sk(sk);
1355 	unsigned int copied, rlen;
1356 	struct sk_buff *skb, *rskb, *cskb, *sskb;
1357 	int blen;
1358 	int err = 0;
1359 
1360 	if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
1361 	    skb_queue_empty(&iucv->backlog_skb_q) &&
1362 	    skb_queue_empty(&sk->sk_receive_queue) &&
1363 	    list_empty(&iucv->message_q.list))
1364 		return 0;
1365 
1366 	if (flags & (MSG_OOB))
1367 		return -EOPNOTSUPP;
1368 
1369 	/* receive/dequeue next skb:
1370 	 * the function understands MSG_PEEK and, thus, does not dequeue skb */
1371 	skb = skb_recv_datagram(sk, flags, noblock, &err);
1372 	if (!skb) {
1373 		if (sk->sk_shutdown & RCV_SHUTDOWN)
1374 			return 0;
1375 		return err;
1376 	}
1377 
1378 	rlen   = skb->len;		/* real length of skb */
1379 	copied = min_t(unsigned int, rlen, len);
1380 
1381 	cskb = skb;
1382 	if (skb_copy_datagram_iovec(cskb, 0, msg->msg_iov, copied)) {
1383 		if (!(flags & MSG_PEEK))
1384 			skb_queue_head(&sk->sk_receive_queue, skb);
1385 		return -EFAULT;
1386 	}
1387 
1388 	/* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1389 	if (sk->sk_type == SOCK_SEQPACKET) {
1390 		if (copied < rlen)
1391 			msg->msg_flags |= MSG_TRUNC;
1392 		/* each iucv message contains a complete record */
1393 		msg->msg_flags |= MSG_EOR;
1394 	}
1395 
1396 	/* create control message to store iucv msg target class:
1397 	 * get the trgcls from the control buffer of the skb due to
1398 	 * fragmentation of original iucv message. */
1399 	err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1400 			CB_TRGCLS_LEN, CB_TRGCLS(skb));
1401 	if (err) {
1402 		if (!(flags & MSG_PEEK))
1403 			skb_queue_head(&sk->sk_receive_queue, skb);
1404 		return err;
1405 	}
1406 
1407 	/* Mark read part of skb as used */
1408 	if (!(flags & MSG_PEEK)) {
1409 
1410 		/* SOCK_STREAM: re-queue skb if it contains unreceived data */
1411 		if (sk->sk_type == SOCK_STREAM) {
1412 			skb_pull(skb, copied);
1413 			if (skb->len) {
1414 				skb_queue_head(&sk->sk_receive_queue, skb);
1415 				goto done;
1416 			}
1417 		}
1418 
1419 		kfree_skb(skb);
1420 		atomic_inc(&iucv->msg_recv);
1421 
1422 		/* Queue backlog skbs */
1423 		spin_lock_bh(&iucv->message_q.lock);
1424 		rskb = skb_dequeue(&iucv->backlog_skb_q);
1425 		while (rskb) {
1426 			if (sock_queue_rcv_skb(sk, rskb)) {
1427 				skb_queue_head(&iucv->backlog_skb_q,
1428 						rskb);
1429 				break;
1430 			} else {
1431 				rskb = skb_dequeue(&iucv->backlog_skb_q);
1432 			}
1433 		}
1434 		if (skb_queue_empty(&iucv->backlog_skb_q)) {
1435 			if (!list_empty(&iucv->message_q.list))
1436 				iucv_process_message_q(sk);
1437 			if (atomic_read(&iucv->msg_recv) >=
1438 							iucv->msglimit / 2) {
1439 				/* send WIN to peer */
1440 				blen = sizeof(struct af_iucv_trans_hdr) +
1441 					ETH_HLEN;
1442 				sskb = sock_alloc_send_skb(sk, blen, 1, &err);
1443 				if (sskb) {
1444 					skb_reserve(sskb,
1445 						sizeof(struct af_iucv_trans_hdr)
1446 						+ ETH_HLEN);
1447 					err = afiucv_hs_send(NULL, sk, sskb,
1448 							     AF_IUCV_FLAG_WIN);
1449 				}
1450 				if (err) {
1451 					sk->sk_state = IUCV_DISCONN;
1452 					sk->sk_state_change(sk);
1453 				}
1454 			}
1455 		}
1456 		spin_unlock_bh(&iucv->message_q.lock);
1457 	}
1458 
1459 done:
1460 	/* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1461 	if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1462 		copied = rlen;
1463 
1464 	return copied;
1465 }
1466 
1467 static inline unsigned int iucv_accept_poll(struct sock *parent)
1468 {
1469 	struct iucv_sock *isk, *n;
1470 	struct sock *sk;
1471 
1472 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1473 		sk = (struct sock *) isk;
1474 
1475 		if (sk->sk_state == IUCV_CONNECTED)
1476 			return POLLIN | POLLRDNORM;
1477 	}
1478 
1479 	return 0;
1480 }
1481 
1482 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1483 			    poll_table *wait)
1484 {
1485 	struct sock *sk = sock->sk;
1486 	unsigned int mask = 0;
1487 
1488 	sock_poll_wait(file, sk_sleep(sk), wait);
1489 
1490 	if (sk->sk_state == IUCV_LISTEN)
1491 		return iucv_accept_poll(sk);
1492 
1493 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1494 		mask |= POLLERR;
1495 
1496 	if (sk->sk_shutdown & RCV_SHUTDOWN)
1497 		mask |= POLLRDHUP;
1498 
1499 	if (sk->sk_shutdown == SHUTDOWN_MASK)
1500 		mask |= POLLHUP;
1501 
1502 	if (!skb_queue_empty(&sk->sk_receive_queue) ||
1503 	    (sk->sk_shutdown & RCV_SHUTDOWN))
1504 		mask |= POLLIN | POLLRDNORM;
1505 
1506 	if (sk->sk_state == IUCV_CLOSED)
1507 		mask |= POLLHUP;
1508 
1509 	if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
1510 		mask |= POLLIN;
1511 
1512 	if (sock_writeable(sk))
1513 		mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1514 	else
1515 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1516 
1517 	return mask;
1518 }
1519 
1520 static int iucv_sock_shutdown(struct socket *sock, int how)
1521 {
1522 	struct sock *sk = sock->sk;
1523 	struct iucv_sock *iucv = iucv_sk(sk);
1524 	struct iucv_message txmsg;
1525 	int err = 0;
1526 
1527 	how++;
1528 
1529 	if ((how & ~SHUTDOWN_MASK) || !how)
1530 		return -EINVAL;
1531 
1532 	lock_sock(sk);
1533 	switch (sk->sk_state) {
1534 	case IUCV_DISCONN:
1535 	case IUCV_CLOSING:
1536 	case IUCV_SEVERED:
1537 	case IUCV_CLOSED:
1538 		err = -ENOTCONN;
1539 		goto fail;
1540 
1541 	default:
1542 		sk->sk_shutdown |= how;
1543 		break;
1544 	}
1545 
1546 	if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1547 		txmsg.class = 0;
1548 		txmsg.tag = 0;
1549 		err = pr_iucv->message_send(iucv->path, &txmsg, IUCV_IPRMDATA,
1550 					0, (void *) iprm_shutdown, 8);
1551 		if (err) {
1552 			switch (err) {
1553 			case 1:
1554 				err = -ENOTCONN;
1555 				break;
1556 			case 2:
1557 				err = -ECONNRESET;
1558 				break;
1559 			default:
1560 				err = -ENOTCONN;
1561 				break;
1562 			}
1563 		}
1564 	}
1565 
1566 	if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1567 		err = pr_iucv->path_quiesce(iucv->path, NULL);
1568 		if (err)
1569 			err = -ENOTCONN;
1570 
1571 		skb_queue_purge(&sk->sk_receive_queue);
1572 	}
1573 
1574 	/* Wake up anyone sleeping in poll */
1575 	sk->sk_state_change(sk);
1576 
1577 fail:
1578 	release_sock(sk);
1579 	return err;
1580 }
1581 
1582 static int iucv_sock_release(struct socket *sock)
1583 {
1584 	struct sock *sk = sock->sk;
1585 	int err = 0;
1586 
1587 	if (!sk)
1588 		return 0;
1589 
1590 	iucv_sock_close(sk);
1591 
1592 	/* Unregister with IUCV base support */
1593 	if (iucv_sk(sk)->path) {
1594 		pr_iucv->path_sever(iucv_sk(sk)->path, NULL);
1595 		iucv_path_free(iucv_sk(sk)->path);
1596 		iucv_sk(sk)->path = NULL;
1597 	}
1598 
1599 	sock_orphan(sk);
1600 	iucv_sock_kill(sk);
1601 	return err;
1602 }
1603 
1604 /* getsockopt and setsockopt */
1605 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1606 				char __user *optval, unsigned int optlen)
1607 {
1608 	struct sock *sk = sock->sk;
1609 	struct iucv_sock *iucv = iucv_sk(sk);
1610 	int val;
1611 	int rc;
1612 
1613 	if (level != SOL_IUCV)
1614 		return -ENOPROTOOPT;
1615 
1616 	if (optlen < sizeof(int))
1617 		return -EINVAL;
1618 
1619 	if (get_user(val, (int __user *) optval))
1620 		return -EFAULT;
1621 
1622 	rc = 0;
1623 
1624 	lock_sock(sk);
1625 	switch (optname) {
1626 	case SO_IPRMDATA_MSG:
1627 		if (val)
1628 			iucv->flags |= IUCV_IPRMDATA;
1629 		else
1630 			iucv->flags &= ~IUCV_IPRMDATA;
1631 		break;
1632 	case SO_MSGLIMIT:
1633 		switch (sk->sk_state) {
1634 		case IUCV_OPEN:
1635 		case IUCV_BOUND:
1636 			if (val < 1 || val > (u16)(~0))
1637 				rc = -EINVAL;
1638 			else
1639 				iucv->msglimit = val;
1640 			break;
1641 		default:
1642 			rc = -EINVAL;
1643 			break;
1644 		}
1645 		break;
1646 	default:
1647 		rc = -ENOPROTOOPT;
1648 		break;
1649 	}
1650 	release_sock(sk);
1651 
1652 	return rc;
1653 }
1654 
1655 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1656 				char __user *optval, int __user *optlen)
1657 {
1658 	struct sock *sk = sock->sk;
1659 	struct iucv_sock *iucv = iucv_sk(sk);
1660 	int val, len;
1661 
1662 	if (level != SOL_IUCV)
1663 		return -ENOPROTOOPT;
1664 
1665 	if (get_user(len, optlen))
1666 		return -EFAULT;
1667 
1668 	if (len < 0)
1669 		return -EINVAL;
1670 
1671 	len = min_t(unsigned int, len, sizeof(int));
1672 
1673 	switch (optname) {
1674 	case SO_IPRMDATA_MSG:
1675 		val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1676 		break;
1677 	case SO_MSGLIMIT:
1678 		lock_sock(sk);
1679 		val = (iucv->path != NULL) ? iucv->path->msglim	/* connected */
1680 					   : iucv->msglimit;	/* default */
1681 		release_sock(sk);
1682 		break;
1683 	default:
1684 		return -ENOPROTOOPT;
1685 	}
1686 
1687 	if (put_user(len, optlen))
1688 		return -EFAULT;
1689 	if (copy_to_user(optval, &val, len))
1690 		return -EFAULT;
1691 
1692 	return 0;
1693 }
1694 
1695 
1696 /* Callback wrappers - called from iucv base support */
1697 static int iucv_callback_connreq(struct iucv_path *path,
1698 				 u8 ipvmid[8], u8 ipuser[16])
1699 {
1700 	unsigned char user_data[16];
1701 	unsigned char nuser_data[16];
1702 	unsigned char src_name[8];
1703 	struct hlist_node *node;
1704 	struct sock *sk, *nsk;
1705 	struct iucv_sock *iucv, *niucv;
1706 	int err;
1707 
1708 	memcpy(src_name, ipuser, 8);
1709 	EBCASC(src_name, 8);
1710 	/* Find out if this path belongs to af_iucv. */
1711 	read_lock(&iucv_sk_list.lock);
1712 	iucv = NULL;
1713 	sk = NULL;
1714 	sk_for_each(sk, node, &iucv_sk_list.head)
1715 		if (sk->sk_state == IUCV_LISTEN &&
1716 		    !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1717 			/*
1718 			 * Found a listening socket with
1719 			 * src_name == ipuser[0-7].
1720 			 */
1721 			iucv = iucv_sk(sk);
1722 			break;
1723 		}
1724 	read_unlock(&iucv_sk_list.lock);
1725 	if (!iucv)
1726 		/* No socket found, not one of our paths. */
1727 		return -EINVAL;
1728 
1729 	bh_lock_sock(sk);
1730 
1731 	/* Check if parent socket is listening */
1732 	low_nmcpy(user_data, iucv->src_name);
1733 	high_nmcpy(user_data, iucv->dst_name);
1734 	ASCEBC(user_data, sizeof(user_data));
1735 	if (sk->sk_state != IUCV_LISTEN) {
1736 		err = pr_iucv->path_sever(path, user_data);
1737 		iucv_path_free(path);
1738 		goto fail;
1739 	}
1740 
1741 	/* Check for backlog size */
1742 	if (sk_acceptq_is_full(sk)) {
1743 		err = pr_iucv->path_sever(path, user_data);
1744 		iucv_path_free(path);
1745 		goto fail;
1746 	}
1747 
1748 	/* Create the new socket */
1749 	nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1750 	if (!nsk) {
1751 		err = pr_iucv->path_sever(path, user_data);
1752 		iucv_path_free(path);
1753 		goto fail;
1754 	}
1755 
1756 	niucv = iucv_sk(nsk);
1757 	iucv_sock_init(nsk, sk);
1758 
1759 	/* Set the new iucv_sock */
1760 	memcpy(niucv->dst_name, ipuser + 8, 8);
1761 	EBCASC(niucv->dst_name, 8);
1762 	memcpy(niucv->dst_user_id, ipvmid, 8);
1763 	memcpy(niucv->src_name, iucv->src_name, 8);
1764 	memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1765 	niucv->path = path;
1766 
1767 	/* Call iucv_accept */
1768 	high_nmcpy(nuser_data, ipuser + 8);
1769 	memcpy(nuser_data + 8, niucv->src_name, 8);
1770 	ASCEBC(nuser_data + 8, 8);
1771 
1772 	/* set message limit for path based on msglimit of accepting socket */
1773 	niucv->msglimit = iucv->msglimit;
1774 	path->msglim = iucv->msglimit;
1775 	err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1776 	if (err) {
1777 		err = pr_iucv->path_sever(path, user_data);
1778 		iucv_path_free(path);
1779 		iucv_sock_kill(nsk);
1780 		goto fail;
1781 	}
1782 
1783 	iucv_accept_enqueue(sk, nsk);
1784 
1785 	/* Wake up accept */
1786 	nsk->sk_state = IUCV_CONNECTED;
1787 	sk->sk_data_ready(sk, 1);
1788 	err = 0;
1789 fail:
1790 	bh_unlock_sock(sk);
1791 	return 0;
1792 }
1793 
1794 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1795 {
1796 	struct sock *sk = path->private;
1797 
1798 	sk->sk_state = IUCV_CONNECTED;
1799 	sk->sk_state_change(sk);
1800 }
1801 
1802 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1803 {
1804 	struct sock *sk = path->private;
1805 	struct iucv_sock *iucv = iucv_sk(sk);
1806 	struct sk_buff *skb;
1807 	struct sock_msg_q *save_msg;
1808 	int len;
1809 
1810 	if (sk->sk_shutdown & RCV_SHUTDOWN) {
1811 		pr_iucv->message_reject(path, msg);
1812 		return;
1813 	}
1814 
1815 	spin_lock(&iucv->message_q.lock);
1816 
1817 	if (!list_empty(&iucv->message_q.list) ||
1818 	    !skb_queue_empty(&iucv->backlog_skb_q))
1819 		goto save_message;
1820 
1821 	len = atomic_read(&sk->sk_rmem_alloc);
1822 	len += SKB_TRUESIZE(iucv_msg_length(msg));
1823 	if (len > sk->sk_rcvbuf)
1824 		goto save_message;
1825 
1826 	skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1827 	if (!skb)
1828 		goto save_message;
1829 
1830 	iucv_process_message(sk, skb, path, msg);
1831 	goto out_unlock;
1832 
1833 save_message:
1834 	save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1835 	if (!save_msg)
1836 		goto out_unlock;
1837 	save_msg->path = path;
1838 	save_msg->msg = *msg;
1839 
1840 	list_add_tail(&save_msg->list, &iucv->message_q.list);
1841 
1842 out_unlock:
1843 	spin_unlock(&iucv->message_q.lock);
1844 }
1845 
1846 static void iucv_callback_txdone(struct iucv_path *path,
1847 				 struct iucv_message *msg)
1848 {
1849 	struct sock *sk = path->private;
1850 	struct sk_buff *this = NULL;
1851 	struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1852 	struct sk_buff *list_skb = list->next;
1853 	unsigned long flags;
1854 
1855 	if (!skb_queue_empty(list)) {
1856 		spin_lock_irqsave(&list->lock, flags);
1857 
1858 		while (list_skb != (struct sk_buff *)list) {
1859 			if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {
1860 				this = list_skb;
1861 				break;
1862 			}
1863 			list_skb = list_skb->next;
1864 		}
1865 		if (this)
1866 			__skb_unlink(this, list);
1867 
1868 		spin_unlock_irqrestore(&list->lock, flags);
1869 
1870 		if (this) {
1871 			kfree_skb(this);
1872 			/* wake up any process waiting for sending */
1873 			iucv_sock_wake_msglim(sk);
1874 		}
1875 	}
1876 	BUG_ON(!this);
1877 
1878 	if (sk->sk_state == IUCV_CLOSING) {
1879 		if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1880 			sk->sk_state = IUCV_CLOSED;
1881 			sk->sk_state_change(sk);
1882 		}
1883 	}
1884 
1885 }
1886 
1887 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1888 {
1889 	struct sock *sk = path->private;
1890 
1891 	if (!list_empty(&iucv_sk(sk)->accept_q))
1892 		sk->sk_state = IUCV_SEVERED;
1893 	else
1894 		sk->sk_state = IUCV_DISCONN;
1895 
1896 	sk->sk_state_change(sk);
1897 }
1898 
1899 /* called if the other communication side shuts down its RECV direction;
1900  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1901  */
1902 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1903 {
1904 	struct sock *sk = path->private;
1905 
1906 	bh_lock_sock(sk);
1907 	if (sk->sk_state != IUCV_CLOSED) {
1908 		sk->sk_shutdown |= SEND_SHUTDOWN;
1909 		sk->sk_state_change(sk);
1910 	}
1911 	bh_unlock_sock(sk);
1912 }
1913 
1914 /***************** HiperSockets transport callbacks ********************/
1915 static void afiucv_swap_src_dest(struct sk_buff *skb)
1916 {
1917 	struct af_iucv_trans_hdr *trans_hdr =
1918 				(struct af_iucv_trans_hdr *)skb->data;
1919 	char tmpID[8];
1920 	char tmpName[8];
1921 
1922 	ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1923 	ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1924 	ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1925 	ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1926 	memcpy(tmpID, trans_hdr->srcUserID, 8);
1927 	memcpy(tmpName, trans_hdr->srcAppName, 8);
1928 	memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1929 	memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1930 	memcpy(trans_hdr->destUserID, tmpID, 8);
1931 	memcpy(trans_hdr->destAppName, tmpName, 8);
1932 	skb_push(skb, ETH_HLEN);
1933 	memset(skb->data, 0, ETH_HLEN);
1934 }
1935 
1936 /**
1937  * afiucv_hs_callback_syn - react on received SYN
1938  **/
1939 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1940 {
1941 	struct sock *nsk;
1942 	struct iucv_sock *iucv, *niucv;
1943 	struct af_iucv_trans_hdr *trans_hdr;
1944 	int err;
1945 
1946 	iucv = iucv_sk(sk);
1947 	trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
1948 	if (!iucv) {
1949 		/* no sock - connection refused */
1950 		afiucv_swap_src_dest(skb);
1951 		trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1952 		err = dev_queue_xmit(skb);
1953 		goto out;
1954 	}
1955 
1956 	nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1957 	bh_lock_sock(sk);
1958 	if ((sk->sk_state != IUCV_LISTEN) ||
1959 	    sk_acceptq_is_full(sk) ||
1960 	    !nsk) {
1961 		/* error on server socket - connection refused */
1962 		if (nsk)
1963 			sk_free(nsk);
1964 		afiucv_swap_src_dest(skb);
1965 		trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1966 		err = dev_queue_xmit(skb);
1967 		bh_unlock_sock(sk);
1968 		goto out;
1969 	}
1970 
1971 	niucv = iucv_sk(nsk);
1972 	iucv_sock_init(nsk, sk);
1973 	niucv->transport = AF_IUCV_TRANS_HIPER;
1974 	niucv->msglimit = iucv->msglimit;
1975 	if (!trans_hdr->window)
1976 		niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1977 	else
1978 		niucv->msglimit_peer = trans_hdr->window;
1979 	memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
1980 	memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
1981 	memcpy(niucv->src_name, iucv->src_name, 8);
1982 	memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1983 	nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
1984 	afiucv_swap_src_dest(skb);
1985 	trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
1986 	trans_hdr->window = niucv->msglimit;
1987 	/* if receiver acks the xmit connection is established */
1988 	err = dev_queue_xmit(skb);
1989 	if (!err) {
1990 		iucv_accept_enqueue(sk, nsk);
1991 		nsk->sk_state = IUCV_CONNECTED;
1992 		sk->sk_data_ready(sk, 1);
1993 	} else
1994 		iucv_sock_kill(nsk);
1995 	bh_unlock_sock(sk);
1996 
1997 out:
1998 	return NET_RX_SUCCESS;
1999 }
2000 
2001 /**
2002  * afiucv_hs_callback_synack() - react on received SYN-ACK
2003  **/
2004 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
2005 {
2006 	struct iucv_sock *iucv = iucv_sk(sk);
2007 	struct af_iucv_trans_hdr *trans_hdr =
2008 					(struct af_iucv_trans_hdr *)skb->data;
2009 
2010 	if (!iucv)
2011 		goto out;
2012 	if (sk->sk_state != IUCV_BOUND)
2013 		goto out;
2014 	bh_lock_sock(sk);
2015 	iucv->msglimit_peer = trans_hdr->window;
2016 	sk->sk_state = IUCV_CONNECTED;
2017 	sk->sk_state_change(sk);
2018 	bh_unlock_sock(sk);
2019 out:
2020 	kfree_skb(skb);
2021 	return NET_RX_SUCCESS;
2022 }
2023 
2024 /**
2025  * afiucv_hs_callback_synfin() - react on received SYN_FIN
2026  **/
2027 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2028 {
2029 	struct iucv_sock *iucv = iucv_sk(sk);
2030 
2031 	if (!iucv)
2032 		goto out;
2033 	if (sk->sk_state != IUCV_BOUND)
2034 		goto out;
2035 	bh_lock_sock(sk);
2036 	sk->sk_state = IUCV_DISCONN;
2037 	sk->sk_state_change(sk);
2038 	bh_unlock_sock(sk);
2039 out:
2040 	kfree_skb(skb);
2041 	return NET_RX_SUCCESS;
2042 }
2043 
2044 /**
2045  * afiucv_hs_callback_fin() - react on received FIN
2046  **/
2047 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2048 {
2049 	struct iucv_sock *iucv = iucv_sk(sk);
2050 
2051 	/* other end of connection closed */
2052 	if (iucv) {
2053 		bh_lock_sock(sk);
2054 		if (!list_empty(&iucv->accept_q))
2055 			sk->sk_state = IUCV_SEVERED;
2056 		else
2057 			sk->sk_state = IUCV_DISCONN;
2058 		sk->sk_state_change(sk);
2059 		bh_unlock_sock(sk);
2060 	}
2061 	kfree_skb(skb);
2062 	return NET_RX_SUCCESS;
2063 }
2064 
2065 /**
2066  * afiucv_hs_callback_win() - react on received WIN
2067  **/
2068 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2069 {
2070 	struct iucv_sock *iucv = iucv_sk(sk);
2071 	struct af_iucv_trans_hdr *trans_hdr =
2072 					(struct af_iucv_trans_hdr *)skb->data;
2073 
2074 	if (!iucv)
2075 		return NET_RX_SUCCESS;
2076 
2077 	if (sk->sk_state != IUCV_CONNECTED)
2078 		return NET_RX_SUCCESS;
2079 
2080 	atomic_sub(trans_hdr->window, &iucv->msg_sent);
2081 	iucv_sock_wake_msglim(sk);
2082 	return NET_RX_SUCCESS;
2083 }
2084 
2085 /**
2086  * afiucv_hs_callback_rx() - react on received data
2087  **/
2088 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2089 {
2090 	struct iucv_sock *iucv = iucv_sk(sk);
2091 
2092 	if (!iucv) {
2093 		kfree_skb(skb);
2094 		return NET_RX_SUCCESS;
2095 	}
2096 
2097 	if (sk->sk_state != IUCV_CONNECTED) {
2098 		kfree_skb(skb);
2099 		return NET_RX_SUCCESS;
2100 	}
2101 
2102 		/* write stuff from iucv_msg to skb cb */
2103 	if (skb->len <= sizeof(struct af_iucv_trans_hdr)) {
2104 		kfree_skb(skb);
2105 		return NET_RX_SUCCESS;
2106 	}
2107 	skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2108 	skb_reset_transport_header(skb);
2109 	skb_reset_network_header(skb);
2110 	spin_lock(&iucv->message_q.lock);
2111 	if (skb_queue_empty(&iucv->backlog_skb_q)) {
2112 		if (sock_queue_rcv_skb(sk, skb)) {
2113 			/* handle rcv queue full */
2114 			skb_queue_tail(&iucv->backlog_skb_q, skb);
2115 		}
2116 	} else
2117 		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2118 	spin_unlock(&iucv->message_q.lock);
2119 	return NET_RX_SUCCESS;
2120 }
2121 
2122 /**
2123  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2124  *                   transport
2125  *                   called from netif RX softirq
2126  **/
2127 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2128 	struct packet_type *pt, struct net_device *orig_dev)
2129 {
2130 	struct hlist_node *node;
2131 	struct sock *sk;
2132 	struct iucv_sock *iucv;
2133 	struct af_iucv_trans_hdr *trans_hdr;
2134 	char nullstring[8];
2135 	int err = 0;
2136 
2137 	skb_pull(skb, ETH_HLEN);
2138 	trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
2139 	EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2140 	EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2141 	EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2142 	EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2143 	memset(nullstring, 0, sizeof(nullstring));
2144 	iucv = NULL;
2145 	sk = NULL;
2146 	read_lock(&iucv_sk_list.lock);
2147 	sk_for_each(sk, node, &iucv_sk_list.head) {
2148 		if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2149 			if ((!memcmp(&iucv_sk(sk)->src_name,
2150 				     trans_hdr->destAppName, 8)) &&
2151 			    (!memcmp(&iucv_sk(sk)->src_user_id,
2152 				     trans_hdr->destUserID, 8)) &&
2153 			    (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2154 			    (!memcmp(&iucv_sk(sk)->dst_user_id,
2155 				     nullstring, 8))) {
2156 				iucv = iucv_sk(sk);
2157 				break;
2158 			}
2159 		} else {
2160 			if ((!memcmp(&iucv_sk(sk)->src_name,
2161 				     trans_hdr->destAppName, 8)) &&
2162 			    (!memcmp(&iucv_sk(sk)->src_user_id,
2163 				     trans_hdr->destUserID, 8)) &&
2164 			    (!memcmp(&iucv_sk(sk)->dst_name,
2165 				     trans_hdr->srcAppName, 8)) &&
2166 			    (!memcmp(&iucv_sk(sk)->dst_user_id,
2167 				     trans_hdr->srcUserID, 8))) {
2168 				iucv = iucv_sk(sk);
2169 				break;
2170 			}
2171 		}
2172 	}
2173 	read_unlock(&iucv_sk_list.lock);
2174 	if (!iucv)
2175 		sk = NULL;
2176 
2177 	/* no sock
2178 	how should we send with no sock
2179 	1) send without sock no send rc checking?
2180 	2) introduce default sock to handle this cases
2181 
2182 	 SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2183 	 data -> send FIN
2184 	 SYN|ACK, SYN|FIN, FIN -> no action? */
2185 
2186 	switch (trans_hdr->flags) {
2187 	case AF_IUCV_FLAG_SYN:
2188 		/* connect request */
2189 		err = afiucv_hs_callback_syn(sk, skb);
2190 		break;
2191 	case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2192 		/* connect request confirmed */
2193 		err = afiucv_hs_callback_synack(sk, skb);
2194 		break;
2195 	case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2196 		/* connect request refused */
2197 		err = afiucv_hs_callback_synfin(sk, skb);
2198 		break;
2199 	case (AF_IUCV_FLAG_FIN):
2200 		/* close request */
2201 		err = afiucv_hs_callback_fin(sk, skb);
2202 		break;
2203 	case (AF_IUCV_FLAG_WIN):
2204 		err = afiucv_hs_callback_win(sk, skb);
2205 		if (skb->len > sizeof(struct af_iucv_trans_hdr))
2206 			err = afiucv_hs_callback_rx(sk, skb);
2207 		else
2208 			kfree(skb);
2209 		break;
2210 	case 0:
2211 		/* plain data frame */
2212 		err = afiucv_hs_callback_rx(sk, skb);
2213 		break;
2214 	default:
2215 		;
2216 	}
2217 
2218 	return err;
2219 }
2220 
2221 /**
2222  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2223  *                                 transport
2224  **/
2225 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2226 					enum iucv_tx_notify n)
2227 {
2228 	struct sock *isk = skb->sk;
2229 	struct sock *sk = NULL;
2230 	struct iucv_sock *iucv = NULL;
2231 	struct sk_buff_head *list;
2232 	struct sk_buff *list_skb;
2233 	struct sk_buff *this = NULL;
2234 	unsigned long flags;
2235 	struct hlist_node *node;
2236 
2237 	read_lock(&iucv_sk_list.lock);
2238 	sk_for_each(sk, node, &iucv_sk_list.head)
2239 		if (sk == isk) {
2240 			iucv = iucv_sk(sk);
2241 			break;
2242 		}
2243 	read_unlock(&iucv_sk_list.lock);
2244 
2245 	if (!iucv)
2246 		return;
2247 
2248 	bh_lock_sock(sk);
2249 	list = &iucv->send_skb_q;
2250 	list_skb = list->next;
2251 	if (skb_queue_empty(list))
2252 		goto out_unlock;
2253 
2254 	spin_lock_irqsave(&list->lock, flags);
2255 	while (list_skb != (struct sk_buff *)list) {
2256 		if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2257 			this = list_skb;
2258 			switch (n) {
2259 			case TX_NOTIFY_OK:
2260 				__skb_unlink(this, list);
2261 				iucv_sock_wake_msglim(sk);
2262 				kfree_skb(this);
2263 				break;
2264 			case TX_NOTIFY_PENDING:
2265 				atomic_inc(&iucv->pendings);
2266 				break;
2267 			case TX_NOTIFY_DELAYED_OK:
2268 				__skb_unlink(this, list);
2269 				atomic_dec(&iucv->pendings);
2270 				if (atomic_read(&iucv->pendings) <= 0)
2271 					iucv_sock_wake_msglim(sk);
2272 				kfree_skb(this);
2273 				break;
2274 			case TX_NOTIFY_UNREACHABLE:
2275 			case TX_NOTIFY_DELAYED_UNREACHABLE:
2276 			case TX_NOTIFY_TPQFULL: /* not yet used */
2277 			case TX_NOTIFY_GENERALERROR:
2278 			case TX_NOTIFY_DELAYED_GENERALERROR:
2279 				__skb_unlink(this, list);
2280 				kfree_skb(this);
2281 				if (!list_empty(&iucv->accept_q))
2282 					sk->sk_state = IUCV_SEVERED;
2283 				else
2284 					sk->sk_state = IUCV_DISCONN;
2285 				sk->sk_state_change(sk);
2286 				break;
2287 			}
2288 			break;
2289 		}
2290 		list_skb = list_skb->next;
2291 	}
2292 	spin_unlock_irqrestore(&list->lock, flags);
2293 
2294 out_unlock:
2295 	bh_unlock_sock(sk);
2296 }
2297 static const struct proto_ops iucv_sock_ops = {
2298 	.family		= PF_IUCV,
2299 	.owner		= THIS_MODULE,
2300 	.release	= iucv_sock_release,
2301 	.bind		= iucv_sock_bind,
2302 	.connect	= iucv_sock_connect,
2303 	.listen		= iucv_sock_listen,
2304 	.accept		= iucv_sock_accept,
2305 	.getname	= iucv_sock_getname,
2306 	.sendmsg	= iucv_sock_sendmsg,
2307 	.recvmsg	= iucv_sock_recvmsg,
2308 	.poll		= iucv_sock_poll,
2309 	.ioctl		= sock_no_ioctl,
2310 	.mmap		= sock_no_mmap,
2311 	.socketpair	= sock_no_socketpair,
2312 	.shutdown	= iucv_sock_shutdown,
2313 	.setsockopt	= iucv_sock_setsockopt,
2314 	.getsockopt	= iucv_sock_getsockopt,
2315 };
2316 
2317 static const struct net_proto_family iucv_sock_family_ops = {
2318 	.family	= AF_IUCV,
2319 	.owner	= THIS_MODULE,
2320 	.create	= iucv_sock_create,
2321 };
2322 
2323 static struct packet_type iucv_packet_type = {
2324 	.type = cpu_to_be16(ETH_P_AF_IUCV),
2325 	.func = afiucv_hs_rcv,
2326 };
2327 
2328 static int afiucv_iucv_init(void)
2329 {
2330 	int err;
2331 
2332 	err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2333 	if (err)
2334 		goto out;
2335 	/* establish dummy device */
2336 	af_iucv_driver.bus = pr_iucv->bus;
2337 	err = driver_register(&af_iucv_driver);
2338 	if (err)
2339 		goto out_iucv;
2340 	af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2341 	if (!af_iucv_dev) {
2342 		err = -ENOMEM;
2343 		goto out_driver;
2344 	}
2345 	dev_set_name(af_iucv_dev, "af_iucv");
2346 	af_iucv_dev->bus = pr_iucv->bus;
2347 	af_iucv_dev->parent = pr_iucv->root;
2348 	af_iucv_dev->release = (void (*)(struct device *))kfree;
2349 	af_iucv_dev->driver = &af_iucv_driver;
2350 	err = device_register(af_iucv_dev);
2351 	if (err)
2352 		goto out_driver;
2353 	return 0;
2354 
2355 out_driver:
2356 	driver_unregister(&af_iucv_driver);
2357 out_iucv:
2358 	pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2359 out:
2360 	return err;
2361 }
2362 
2363 static int __init afiucv_init(void)
2364 {
2365 	int err;
2366 
2367 	if (MACHINE_IS_VM) {
2368 		cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2369 		if (unlikely(err)) {
2370 			WARN_ON(err);
2371 			err = -EPROTONOSUPPORT;
2372 			goto out;
2373 		}
2374 
2375 		pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2376 		if (!pr_iucv) {
2377 			printk(KERN_WARNING "iucv_if lookup failed\n");
2378 			memset(&iucv_userid, 0, sizeof(iucv_userid));
2379 		}
2380 	} else {
2381 		memset(&iucv_userid, 0, sizeof(iucv_userid));
2382 		pr_iucv = NULL;
2383 	}
2384 
2385 	err = proto_register(&iucv_proto, 0);
2386 	if (err)
2387 		goto out;
2388 	err = sock_register(&iucv_sock_family_ops);
2389 	if (err)
2390 		goto out_proto;
2391 
2392 	if (pr_iucv) {
2393 		err = afiucv_iucv_init();
2394 		if (err)
2395 			goto out_sock;
2396 	}
2397 	dev_add_pack(&iucv_packet_type);
2398 	return 0;
2399 
2400 out_sock:
2401 	sock_unregister(PF_IUCV);
2402 out_proto:
2403 	proto_unregister(&iucv_proto);
2404 out:
2405 	if (pr_iucv)
2406 		symbol_put(iucv_if);
2407 	return err;
2408 }
2409 
2410 static void __exit afiucv_exit(void)
2411 {
2412 	if (pr_iucv) {
2413 		device_unregister(af_iucv_dev);
2414 		driver_unregister(&af_iucv_driver);
2415 		pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2416 		symbol_put(iucv_if);
2417 	}
2418 	dev_remove_pack(&iucv_packet_type);
2419 	sock_unregister(PF_IUCV);
2420 	proto_unregister(&iucv_proto);
2421 }
2422 
2423 module_init(afiucv_init);
2424 module_exit(afiucv_exit);
2425 
2426 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2427 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2428 MODULE_VERSION(VERSION);
2429 MODULE_LICENSE("GPL");
2430 MODULE_ALIAS_NETPROTO(PF_IUCV);
2431 
2432