xref: /linux/net/iucv/af_iucv.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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 static void iucv_sever_path(struct sock *, int);
94 
95 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
96 	struct packet_type *pt, struct net_device *orig_dev);
97 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
98 		   struct sk_buff *skb, u8 flags);
99 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
100 
101 /* Call Back functions */
102 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
103 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
104 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
105 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
106 				 u8 ipuser[16]);
107 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
108 static void iucv_callback_shutdown(struct iucv_path *, u8 ipuser[16]);
109 
110 static struct iucv_sock_list iucv_sk_list = {
111 	.lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
112 	.autobind_name = ATOMIC_INIT(0)
113 };
114 
115 static struct iucv_handler af_iucv_handler = {
116 	.path_pending	  = iucv_callback_connreq,
117 	.path_complete	  = iucv_callback_connack,
118 	.path_severed	  = iucv_callback_connrej,
119 	.message_pending  = iucv_callback_rx,
120 	.message_complete = iucv_callback_txdone,
121 	.path_quiesced	  = iucv_callback_shutdown,
122 };
123 
124 static inline void high_nmcpy(unsigned char *dst, char *src)
125 {
126        memcpy(dst, src, 8);
127 }
128 
129 static inline void low_nmcpy(unsigned char *dst, char *src)
130 {
131        memcpy(&dst[8], src, 8);
132 }
133 
134 static int afiucv_pm_prepare(struct device *dev)
135 {
136 #ifdef CONFIG_PM_DEBUG
137 	printk(KERN_WARNING "afiucv_pm_prepare\n");
138 #endif
139 	return 0;
140 }
141 
142 static void afiucv_pm_complete(struct device *dev)
143 {
144 #ifdef CONFIG_PM_DEBUG
145 	printk(KERN_WARNING "afiucv_pm_complete\n");
146 #endif
147 }
148 
149 /**
150  * afiucv_pm_freeze() - Freeze PM callback
151  * @dev:	AFIUCV dummy device
152  *
153  * Sever all established IUCV communication pathes
154  */
155 static int afiucv_pm_freeze(struct device *dev)
156 {
157 	struct iucv_sock *iucv;
158 	struct sock *sk;
159 	struct hlist_node *node;
160 	int err = 0;
161 
162 #ifdef CONFIG_PM_DEBUG
163 	printk(KERN_WARNING "afiucv_pm_freeze\n");
164 #endif
165 	read_lock(&iucv_sk_list.lock);
166 	sk_for_each(sk, node, &iucv_sk_list.head) {
167 		iucv = iucv_sk(sk);
168 		switch (sk->sk_state) {
169 		case IUCV_DISCONN:
170 		case IUCV_CLOSING:
171 		case IUCV_CONNECTED:
172 			iucv_sever_path(sk, 0);
173 			break;
174 		case IUCV_OPEN:
175 		case IUCV_BOUND:
176 		case IUCV_LISTEN:
177 		case IUCV_CLOSED:
178 		default:
179 			break;
180 		}
181 		skb_queue_purge(&iucv->send_skb_q);
182 		skb_queue_purge(&iucv->backlog_skb_q);
183 	}
184 	read_unlock(&iucv_sk_list.lock);
185 	return err;
186 }
187 
188 /**
189  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
190  * @dev:	AFIUCV dummy device
191  *
192  * socket clean up after freeze
193  */
194 static int afiucv_pm_restore_thaw(struct device *dev)
195 {
196 	struct sock *sk;
197 	struct hlist_node *node;
198 
199 #ifdef CONFIG_PM_DEBUG
200 	printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
201 #endif
202 	read_lock(&iucv_sk_list.lock);
203 	sk_for_each(sk, node, &iucv_sk_list.head) {
204 		switch (sk->sk_state) {
205 		case IUCV_CONNECTED:
206 			sk->sk_err = EPIPE;
207 			sk->sk_state = IUCV_DISCONN;
208 			sk->sk_state_change(sk);
209 			break;
210 		case IUCV_DISCONN:
211 		case IUCV_CLOSING:
212 		case IUCV_LISTEN:
213 		case IUCV_BOUND:
214 		case IUCV_OPEN:
215 		default:
216 			break;
217 		}
218 	}
219 	read_unlock(&iucv_sk_list.lock);
220 	return 0;
221 }
222 
223 static const struct dev_pm_ops afiucv_pm_ops = {
224 	.prepare = afiucv_pm_prepare,
225 	.complete = afiucv_pm_complete,
226 	.freeze = afiucv_pm_freeze,
227 	.thaw = afiucv_pm_restore_thaw,
228 	.restore = afiucv_pm_restore_thaw,
229 };
230 
231 static struct device_driver af_iucv_driver = {
232 	.owner = THIS_MODULE,
233 	.name = "afiucv",
234 	.bus  = NULL,
235 	.pm   = &afiucv_pm_ops,
236 };
237 
238 /* dummy device used as trigger for PM functions */
239 static struct device *af_iucv_dev;
240 
241 /**
242  * iucv_msg_length() - Returns the length of an iucv message.
243  * @msg:	Pointer to struct iucv_message, MUST NOT be NULL
244  *
245  * The function returns the length of the specified iucv message @msg of data
246  * stored in a buffer and of data stored in the parameter list (PRMDATA).
247  *
248  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
249  * data:
250  *	PRMDATA[0..6]	socket data (max 7 bytes);
251  *	PRMDATA[7]	socket data length value (len is 0xff - PRMDATA[7])
252  *
253  * The socket data length is computed by subtracting the socket data length
254  * value from 0xFF.
255  * If the socket data len is greater 7, then PRMDATA can be used for special
256  * notifications (see iucv_sock_shutdown); and further,
257  * if the socket data len is > 7, the function returns 8.
258  *
259  * Use this function to allocate socket buffers to store iucv message data.
260  */
261 static inline size_t iucv_msg_length(struct iucv_message *msg)
262 {
263 	size_t datalen;
264 
265 	if (msg->flags & IUCV_IPRMDATA) {
266 		datalen = 0xff - msg->rmmsg[7];
267 		return (datalen < 8) ? datalen : 8;
268 	}
269 	return msg->length;
270 }
271 
272 /**
273  * iucv_sock_in_state() - check for specific states
274  * @sk:		sock structure
275  * @state:	first iucv sk state
276  * @state:	second iucv sk state
277  *
278  * Returns true if the socket in either in the first or second state.
279  */
280 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
281 {
282 	return (sk->sk_state == state || sk->sk_state == state2);
283 }
284 
285 /**
286  * iucv_below_msglim() - function to check if messages can be sent
287  * @sk:		sock structure
288  *
289  * Returns true if the send queue length is lower than the message limit.
290  * Always returns true if the socket is not connected (no iucv path for
291  * checking the message limit).
292  */
293 static inline int iucv_below_msglim(struct sock *sk)
294 {
295 	struct iucv_sock *iucv = iucv_sk(sk);
296 
297 	if (sk->sk_state != IUCV_CONNECTED)
298 		return 1;
299 	if (iucv->transport == AF_IUCV_TRANS_IUCV)
300 		return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
301 	else
302 		return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
303 			(atomic_read(&iucv->pendings) <= 0));
304 }
305 
306 /**
307  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
308  */
309 static void iucv_sock_wake_msglim(struct sock *sk)
310 {
311 	struct socket_wq *wq;
312 
313 	rcu_read_lock();
314 	wq = rcu_dereference(sk->sk_wq);
315 	if (wq_has_sleeper(wq))
316 		wake_up_interruptible_all(&wq->wait);
317 	sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
318 	rcu_read_unlock();
319 }
320 
321 /**
322  * afiucv_hs_send() - send a message through HiperSockets transport
323  */
324 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
325 		   struct sk_buff *skb, u8 flags)
326 {
327 	struct iucv_sock *iucv = iucv_sk(sock);
328 	struct af_iucv_trans_hdr *phs_hdr;
329 	struct sk_buff *nskb;
330 	int err, confirm_recv = 0;
331 
332 	memset(skb->head, 0, ETH_HLEN);
333 	phs_hdr = (struct af_iucv_trans_hdr *)skb_push(skb,
334 					sizeof(struct af_iucv_trans_hdr));
335 	skb_reset_mac_header(skb);
336 	skb_reset_network_header(skb);
337 	skb_push(skb, ETH_HLEN);
338 	skb_reset_mac_header(skb);
339 	memset(phs_hdr, 0, sizeof(struct af_iucv_trans_hdr));
340 
341 	phs_hdr->magic = ETH_P_AF_IUCV;
342 	phs_hdr->version = 1;
343 	phs_hdr->flags = flags;
344 	if (flags == AF_IUCV_FLAG_SYN)
345 		phs_hdr->window = iucv->msglimit;
346 	else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
347 		confirm_recv = atomic_read(&iucv->msg_recv);
348 		phs_hdr->window = confirm_recv;
349 		if (confirm_recv)
350 			phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
351 	}
352 	memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
353 	memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
354 	memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
355 	memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
356 	ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
357 	ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
358 	ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
359 	ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
360 	if (imsg)
361 		memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
362 
363 	skb->dev = iucv->hs_dev;
364 	if (!skb->dev)
365 		return -ENODEV;
366 	if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev))
367 		return -ENETDOWN;
368 	if (skb->len > skb->dev->mtu) {
369 		if (sock->sk_type == SOCK_SEQPACKET)
370 			return -EMSGSIZE;
371 		else
372 			skb_trim(skb, skb->dev->mtu);
373 	}
374 	skb->protocol = ETH_P_AF_IUCV;
375 	nskb = skb_clone(skb, GFP_ATOMIC);
376 	if (!nskb)
377 		return -ENOMEM;
378 	skb_queue_tail(&iucv->send_skb_q, nskb);
379 	err = dev_queue_xmit(skb);
380 	if (net_xmit_eval(err)) {
381 		skb_unlink(nskb, &iucv->send_skb_q);
382 		kfree_skb(nskb);
383 	} else {
384 		atomic_sub(confirm_recv, &iucv->msg_recv);
385 		WARN_ON(atomic_read(&iucv->msg_recv) < 0);
386 	}
387 	return net_xmit_eval(err);
388 }
389 
390 static struct sock *__iucv_get_sock_by_name(char *nm)
391 {
392 	struct sock *sk;
393 	struct hlist_node *node;
394 
395 	sk_for_each(sk, node, &iucv_sk_list.head)
396 		if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
397 			return sk;
398 
399 	return NULL;
400 }
401 
402 static void iucv_sock_destruct(struct sock *sk)
403 {
404 	skb_queue_purge(&sk->sk_receive_queue);
405 	skb_queue_purge(&sk->sk_error_queue);
406 
407 	sk_mem_reclaim(sk);
408 
409 	if (!sock_flag(sk, SOCK_DEAD)) {
410 		pr_err("Attempt to release alive iucv socket %p\n", sk);
411 		return;
412 	}
413 
414 	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
415 	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
416 	WARN_ON(sk->sk_wmem_queued);
417 	WARN_ON(sk->sk_forward_alloc);
418 }
419 
420 /* Cleanup Listen */
421 static void iucv_sock_cleanup_listen(struct sock *parent)
422 {
423 	struct sock *sk;
424 
425 	/* Close non-accepted connections */
426 	while ((sk = iucv_accept_dequeue(parent, NULL))) {
427 		iucv_sock_close(sk);
428 		iucv_sock_kill(sk);
429 	}
430 
431 	parent->sk_state = IUCV_CLOSED;
432 }
433 
434 /* Kill socket (only if zapped and orphaned) */
435 static void iucv_sock_kill(struct sock *sk)
436 {
437 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
438 		return;
439 
440 	iucv_sock_unlink(&iucv_sk_list, sk);
441 	sock_set_flag(sk, SOCK_DEAD);
442 	sock_put(sk);
443 }
444 
445 /* Terminate an IUCV path */
446 static void iucv_sever_path(struct sock *sk, int with_user_data)
447 {
448 	unsigned char user_data[16];
449 	struct iucv_sock *iucv = iucv_sk(sk);
450 	struct iucv_path *path = iucv->path;
451 
452 	if (iucv->path) {
453 		iucv->path = NULL;
454 		if (with_user_data) {
455 			low_nmcpy(user_data, iucv->src_name);
456 			high_nmcpy(user_data, iucv->dst_name);
457 			ASCEBC(user_data, sizeof(user_data));
458 			pr_iucv->path_sever(path, user_data);
459 		} else
460 			pr_iucv->path_sever(path, NULL);
461 		iucv_path_free(path);
462 	}
463 }
464 
465 /* Send FIN through an IUCV socket for HIPER transport */
466 static int iucv_send_ctrl(struct sock *sk, u8 flags)
467 {
468 	int err = 0;
469 	int blen;
470 	struct sk_buff *skb;
471 
472 	blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
473 	skb = sock_alloc_send_skb(sk, blen, 1, &err);
474 	if (skb) {
475 		skb_reserve(skb, blen);
476 		err = afiucv_hs_send(NULL, sk, skb, flags);
477 	}
478 	return err;
479 }
480 
481 /* Close an IUCV socket */
482 static void iucv_sock_close(struct sock *sk)
483 {
484 	struct iucv_sock *iucv = iucv_sk(sk);
485 	unsigned long timeo;
486 	int err = 0;
487 
488 	lock_sock(sk);
489 
490 	switch (sk->sk_state) {
491 	case IUCV_LISTEN:
492 		iucv_sock_cleanup_listen(sk);
493 		break;
494 
495 	case IUCV_CONNECTED:
496 		if (iucv->transport == AF_IUCV_TRANS_HIPER) {
497 			err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
498 			sk->sk_state = IUCV_DISCONN;
499 			sk->sk_state_change(sk);
500 		}
501 	case IUCV_DISCONN:   /* fall through */
502 		sk->sk_state = IUCV_CLOSING;
503 		sk->sk_state_change(sk);
504 
505 		if (!err && !skb_queue_empty(&iucv->send_skb_q)) {
506 			if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
507 				timeo = sk->sk_lingertime;
508 			else
509 				timeo = IUCV_DISCONN_TIMEOUT;
510 			iucv_sock_wait(sk,
511 					iucv_sock_in_state(sk, IUCV_CLOSED, 0),
512 					timeo);
513 		}
514 
515 	case IUCV_CLOSING:   /* fall through */
516 		sk->sk_state = IUCV_CLOSED;
517 		sk->sk_state_change(sk);
518 
519 		sk->sk_err = ECONNRESET;
520 		sk->sk_state_change(sk);
521 
522 		skb_queue_purge(&iucv->send_skb_q);
523 		skb_queue_purge(&iucv->backlog_skb_q);
524 
525 	default:   /* fall through */
526 		iucv_sever_path(sk, 1);
527 	}
528 
529 	if (iucv->hs_dev) {
530 		dev_put(iucv->hs_dev);
531 		iucv->hs_dev = NULL;
532 		sk->sk_bound_dev_if = 0;
533 	}
534 
535 	/* mark socket for deletion by iucv_sock_kill() */
536 	sock_set_flag(sk, SOCK_ZAPPED);
537 
538 	release_sock(sk);
539 }
540 
541 static void iucv_sock_init(struct sock *sk, struct sock *parent)
542 {
543 	if (parent)
544 		sk->sk_type = parent->sk_type;
545 }
546 
547 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
548 {
549 	struct sock *sk;
550 	struct iucv_sock *iucv;
551 
552 	sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
553 	if (!sk)
554 		return NULL;
555 	iucv = iucv_sk(sk);
556 
557 	sock_init_data(sock, sk);
558 	INIT_LIST_HEAD(&iucv->accept_q);
559 	spin_lock_init(&iucv->accept_q_lock);
560 	skb_queue_head_init(&iucv->send_skb_q);
561 	INIT_LIST_HEAD(&iucv->message_q.list);
562 	spin_lock_init(&iucv->message_q.lock);
563 	skb_queue_head_init(&iucv->backlog_skb_q);
564 	iucv->send_tag = 0;
565 	atomic_set(&iucv->pendings, 0);
566 	iucv->flags = 0;
567 	iucv->msglimit = 0;
568 	atomic_set(&iucv->msg_sent, 0);
569 	atomic_set(&iucv->msg_recv, 0);
570 	iucv->path = NULL;
571 	iucv->sk_txnotify = afiucv_hs_callback_txnotify;
572 	memset(&iucv->src_user_id , 0, 32);
573 	if (pr_iucv)
574 		iucv->transport = AF_IUCV_TRANS_IUCV;
575 	else
576 		iucv->transport = AF_IUCV_TRANS_HIPER;
577 
578 	sk->sk_destruct = iucv_sock_destruct;
579 	sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
580 	sk->sk_allocation = GFP_DMA;
581 
582 	sock_reset_flag(sk, SOCK_ZAPPED);
583 
584 	sk->sk_protocol = proto;
585 	sk->sk_state	= IUCV_OPEN;
586 
587 	iucv_sock_link(&iucv_sk_list, sk);
588 	return sk;
589 }
590 
591 /* Create an IUCV socket */
592 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
593 			    int kern)
594 {
595 	struct sock *sk;
596 
597 	if (protocol && protocol != PF_IUCV)
598 		return -EPROTONOSUPPORT;
599 
600 	sock->state = SS_UNCONNECTED;
601 
602 	switch (sock->type) {
603 	case SOCK_STREAM:
604 		sock->ops = &iucv_sock_ops;
605 		break;
606 	case SOCK_SEQPACKET:
607 		/* currently, proto ops can handle both sk types */
608 		sock->ops = &iucv_sock_ops;
609 		break;
610 	default:
611 		return -ESOCKTNOSUPPORT;
612 	}
613 
614 	sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
615 	if (!sk)
616 		return -ENOMEM;
617 
618 	iucv_sock_init(sk, NULL);
619 
620 	return 0;
621 }
622 
623 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
624 {
625 	write_lock_bh(&l->lock);
626 	sk_add_node(sk, &l->head);
627 	write_unlock_bh(&l->lock);
628 }
629 
630 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
631 {
632 	write_lock_bh(&l->lock);
633 	sk_del_node_init(sk);
634 	write_unlock_bh(&l->lock);
635 }
636 
637 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
638 {
639 	unsigned long flags;
640 	struct iucv_sock *par = iucv_sk(parent);
641 
642 	sock_hold(sk);
643 	spin_lock_irqsave(&par->accept_q_lock, flags);
644 	list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
645 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
646 	iucv_sk(sk)->parent = parent;
647 	sk_acceptq_added(parent);
648 }
649 
650 void iucv_accept_unlink(struct sock *sk)
651 {
652 	unsigned long flags;
653 	struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
654 
655 	spin_lock_irqsave(&par->accept_q_lock, flags);
656 	list_del_init(&iucv_sk(sk)->accept_q);
657 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
658 	sk_acceptq_removed(iucv_sk(sk)->parent);
659 	iucv_sk(sk)->parent = NULL;
660 	sock_put(sk);
661 }
662 
663 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
664 {
665 	struct iucv_sock *isk, *n;
666 	struct sock *sk;
667 
668 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
669 		sk = (struct sock *) isk;
670 		lock_sock(sk);
671 
672 		if (sk->sk_state == IUCV_CLOSED) {
673 			iucv_accept_unlink(sk);
674 			release_sock(sk);
675 			continue;
676 		}
677 
678 		if (sk->sk_state == IUCV_CONNECTED ||
679 		    sk->sk_state == IUCV_DISCONN ||
680 		    !newsock) {
681 			iucv_accept_unlink(sk);
682 			if (newsock)
683 				sock_graft(sk, newsock);
684 
685 			release_sock(sk);
686 			return sk;
687 		}
688 
689 		release_sock(sk);
690 	}
691 	return NULL;
692 }
693 
694 /* Bind an unbound socket */
695 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
696 			  int addr_len)
697 {
698 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
699 	struct sock *sk = sock->sk;
700 	struct iucv_sock *iucv;
701 	int err = 0;
702 	struct net_device *dev;
703 	char uid[9];
704 
705 	/* Verify the input sockaddr */
706 	if (!addr || addr->sa_family != AF_IUCV)
707 		return -EINVAL;
708 
709 	lock_sock(sk);
710 	if (sk->sk_state != IUCV_OPEN) {
711 		err = -EBADFD;
712 		goto done;
713 	}
714 
715 	write_lock_bh(&iucv_sk_list.lock);
716 
717 	iucv = iucv_sk(sk);
718 	if (__iucv_get_sock_by_name(sa->siucv_name)) {
719 		err = -EADDRINUSE;
720 		goto done_unlock;
721 	}
722 	if (iucv->path)
723 		goto done_unlock;
724 
725 	/* Bind the socket */
726 	if (pr_iucv)
727 		if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
728 			goto vm_bind; /* VM IUCV transport */
729 
730 	/* try hiper transport */
731 	memcpy(uid, sa->siucv_user_id, sizeof(uid));
732 	ASCEBC(uid, 8);
733 	rcu_read_lock();
734 	for_each_netdev_rcu(&init_net, dev) {
735 		if (!memcmp(dev->perm_addr, uid, 8)) {
736 			memcpy(iucv->src_name, sa->siucv_name, 8);
737 			memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
738 			sk->sk_bound_dev_if = dev->ifindex;
739 			iucv->hs_dev = dev;
740 			dev_hold(dev);
741 			sk->sk_state = IUCV_BOUND;
742 			iucv->transport = AF_IUCV_TRANS_HIPER;
743 			if (!iucv->msglimit)
744 				iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
745 			rcu_read_unlock();
746 			goto done_unlock;
747 		}
748 	}
749 	rcu_read_unlock();
750 vm_bind:
751 	if (pr_iucv) {
752 		/* use local userid for backward compat */
753 		memcpy(iucv->src_name, sa->siucv_name, 8);
754 		memcpy(iucv->src_user_id, iucv_userid, 8);
755 		sk->sk_state = IUCV_BOUND;
756 		iucv->transport = AF_IUCV_TRANS_IUCV;
757 		if (!iucv->msglimit)
758 			iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
759 		goto done_unlock;
760 	}
761 	/* found no dev to bind */
762 	err = -ENODEV;
763 done_unlock:
764 	/* Release the socket list lock */
765 	write_unlock_bh(&iucv_sk_list.lock);
766 done:
767 	release_sock(sk);
768 	return err;
769 }
770 
771 /* Automatically bind an unbound socket */
772 static int iucv_sock_autobind(struct sock *sk)
773 {
774 	struct iucv_sock *iucv = iucv_sk(sk);
775 	char name[12];
776 	int err = 0;
777 
778 	if (unlikely(!pr_iucv))
779 		return -EPROTO;
780 
781 	memcpy(iucv->src_user_id, iucv_userid, 8);
782 
783 	write_lock_bh(&iucv_sk_list.lock);
784 
785 	sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
786 	while (__iucv_get_sock_by_name(name)) {
787 		sprintf(name, "%08x",
788 			atomic_inc_return(&iucv_sk_list.autobind_name));
789 	}
790 
791 	write_unlock_bh(&iucv_sk_list.lock);
792 
793 	memcpy(&iucv->src_name, name, 8);
794 
795 	if (!iucv->msglimit)
796 		iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
797 
798 	return err;
799 }
800 
801 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
802 {
803 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
804 	struct sock *sk = sock->sk;
805 	struct iucv_sock *iucv = iucv_sk(sk);
806 	unsigned char user_data[16];
807 	int err;
808 
809 	high_nmcpy(user_data, sa->siucv_name);
810 	low_nmcpy(user_data, iucv->src_name);
811 	ASCEBC(user_data, sizeof(user_data));
812 
813 	/* Create path. */
814 	iucv->path = iucv_path_alloc(iucv->msglimit,
815 				     IUCV_IPRMDATA, GFP_KERNEL);
816 	if (!iucv->path) {
817 		err = -ENOMEM;
818 		goto done;
819 	}
820 	err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
821 				    sa->siucv_user_id, NULL, user_data,
822 				    sk);
823 	if (err) {
824 		iucv_path_free(iucv->path);
825 		iucv->path = NULL;
826 		switch (err) {
827 		case 0x0b:	/* Target communicator is not logged on */
828 			err = -ENETUNREACH;
829 			break;
830 		case 0x0d:	/* Max connections for this guest exceeded */
831 		case 0x0e:	/* Max connections for target guest exceeded */
832 			err = -EAGAIN;
833 			break;
834 		case 0x0f:	/* Missing IUCV authorization */
835 			err = -EACCES;
836 			break;
837 		default:
838 			err = -ECONNREFUSED;
839 			break;
840 		}
841 	}
842 done:
843 	return err;
844 }
845 
846 /* Connect an unconnected socket */
847 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
848 			     int alen, int flags)
849 {
850 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
851 	struct sock *sk = sock->sk;
852 	struct iucv_sock *iucv = iucv_sk(sk);
853 	int err;
854 
855 	if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
856 		return -EINVAL;
857 
858 	if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
859 		return -EBADFD;
860 
861 	if (sk->sk_state == IUCV_OPEN &&
862 	    iucv->transport == AF_IUCV_TRANS_HIPER)
863 		return -EBADFD; /* explicit bind required */
864 
865 	if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
866 		return -EINVAL;
867 
868 	if (sk->sk_state == IUCV_OPEN) {
869 		err = iucv_sock_autobind(sk);
870 		if (unlikely(err))
871 			return err;
872 	}
873 
874 	lock_sock(sk);
875 
876 	/* Set the destination information */
877 	memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
878 	memcpy(iucv->dst_name, sa->siucv_name, 8);
879 
880 	if (iucv->transport == AF_IUCV_TRANS_HIPER)
881 		err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
882 	else
883 		err = afiucv_path_connect(sock, addr);
884 	if (err)
885 		goto done;
886 
887 	if (sk->sk_state != IUCV_CONNECTED)
888 		err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
889 							    IUCV_DISCONN),
890 				     sock_sndtimeo(sk, flags & O_NONBLOCK));
891 
892 	if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
893 		err = -ECONNREFUSED;
894 
895 	if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
896 		iucv_sever_path(sk, 0);
897 
898 done:
899 	release_sock(sk);
900 	return err;
901 }
902 
903 /* Move a socket into listening state. */
904 static int iucv_sock_listen(struct socket *sock, int backlog)
905 {
906 	struct sock *sk = sock->sk;
907 	int err;
908 
909 	lock_sock(sk);
910 
911 	err = -EINVAL;
912 	if (sk->sk_state != IUCV_BOUND)
913 		goto done;
914 
915 	if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
916 		goto done;
917 
918 	sk->sk_max_ack_backlog = backlog;
919 	sk->sk_ack_backlog = 0;
920 	sk->sk_state = IUCV_LISTEN;
921 	err = 0;
922 
923 done:
924 	release_sock(sk);
925 	return err;
926 }
927 
928 /* Accept a pending connection */
929 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
930 			    int flags)
931 {
932 	DECLARE_WAITQUEUE(wait, current);
933 	struct sock *sk = sock->sk, *nsk;
934 	long timeo;
935 	int err = 0;
936 
937 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
938 
939 	if (sk->sk_state != IUCV_LISTEN) {
940 		err = -EBADFD;
941 		goto done;
942 	}
943 
944 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
945 
946 	/* Wait for an incoming connection */
947 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
948 	while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
949 		set_current_state(TASK_INTERRUPTIBLE);
950 		if (!timeo) {
951 			err = -EAGAIN;
952 			break;
953 		}
954 
955 		release_sock(sk);
956 		timeo = schedule_timeout(timeo);
957 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
958 
959 		if (sk->sk_state != IUCV_LISTEN) {
960 			err = -EBADFD;
961 			break;
962 		}
963 
964 		if (signal_pending(current)) {
965 			err = sock_intr_errno(timeo);
966 			break;
967 		}
968 	}
969 
970 	set_current_state(TASK_RUNNING);
971 	remove_wait_queue(sk_sleep(sk), &wait);
972 
973 	if (err)
974 		goto done;
975 
976 	newsock->state = SS_CONNECTED;
977 
978 done:
979 	release_sock(sk);
980 	return err;
981 }
982 
983 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
984 			     int *len, int peer)
985 {
986 	struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
987 	struct sock *sk = sock->sk;
988 	struct iucv_sock *iucv = iucv_sk(sk);
989 
990 	addr->sa_family = AF_IUCV;
991 	*len = sizeof(struct sockaddr_iucv);
992 
993 	if (peer) {
994 		memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
995 		memcpy(siucv->siucv_name, iucv->dst_name, 8);
996 	} else {
997 		memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
998 		memcpy(siucv->siucv_name, iucv->src_name, 8);
999 	}
1000 	memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
1001 	memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
1002 	memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
1003 
1004 	return 0;
1005 }
1006 
1007 /**
1008  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1009  * @path:	IUCV path
1010  * @msg:	Pointer to a struct iucv_message
1011  * @skb:	The socket data to send, skb->len MUST BE <= 7
1012  *
1013  * Send the socket data in the parameter list in the iucv message
1014  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1015  * list and the socket data len at index 7 (last byte).
1016  * See also iucv_msg_length().
1017  *
1018  * Returns the error code from the iucv_message_send() call.
1019  */
1020 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1021 			  struct sk_buff *skb)
1022 {
1023 	u8 prmdata[8];
1024 
1025 	memcpy(prmdata, (void *) skb->data, skb->len);
1026 	prmdata[7] = 0xff - (u8) skb->len;
1027 	return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1028 				 (void *) prmdata, 8);
1029 }
1030 
1031 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
1032 			     struct msghdr *msg, size_t len)
1033 {
1034 	struct sock *sk = sock->sk;
1035 	struct iucv_sock *iucv = iucv_sk(sk);
1036 	struct sk_buff *skb;
1037 	struct iucv_message txmsg;
1038 	struct cmsghdr *cmsg;
1039 	int cmsg_done;
1040 	long timeo;
1041 	char user_id[9];
1042 	char appl_id[9];
1043 	int err;
1044 	int noblock = msg->msg_flags & MSG_DONTWAIT;
1045 
1046 	err = sock_error(sk);
1047 	if (err)
1048 		return err;
1049 
1050 	if (msg->msg_flags & MSG_OOB)
1051 		return -EOPNOTSUPP;
1052 
1053 	/* SOCK_SEQPACKET: we do not support segmented records */
1054 	if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1055 		return -EOPNOTSUPP;
1056 
1057 	lock_sock(sk);
1058 
1059 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1060 		err = -EPIPE;
1061 		goto out;
1062 	}
1063 
1064 	/* Return if the socket is not in connected state */
1065 	if (sk->sk_state != IUCV_CONNECTED) {
1066 		err = -ENOTCONN;
1067 		goto out;
1068 	}
1069 
1070 	/* initialize defaults */
1071 	cmsg_done   = 0;	/* check for duplicate headers */
1072 	txmsg.class = 0;
1073 
1074 	/* iterate over control messages */
1075 	for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
1076 		cmsg = CMSG_NXTHDR(msg, cmsg)) {
1077 
1078 		if (!CMSG_OK(msg, cmsg)) {
1079 			err = -EINVAL;
1080 			goto out;
1081 		}
1082 
1083 		if (cmsg->cmsg_level != SOL_IUCV)
1084 			continue;
1085 
1086 		if (cmsg->cmsg_type & cmsg_done) {
1087 			err = -EINVAL;
1088 			goto out;
1089 		}
1090 		cmsg_done |= cmsg->cmsg_type;
1091 
1092 		switch (cmsg->cmsg_type) {
1093 		case SCM_IUCV_TRGCLS:
1094 			if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1095 				err = -EINVAL;
1096 				goto out;
1097 			}
1098 
1099 			/* set iucv message target class */
1100 			memcpy(&txmsg.class,
1101 				(void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1102 
1103 			break;
1104 
1105 		default:
1106 			err = -EINVAL;
1107 			goto out;
1108 			break;
1109 		}
1110 	}
1111 
1112 	/* allocate one skb for each iucv message:
1113 	 * this is fine for SOCK_SEQPACKET (unless we want to support
1114 	 * segmented records using the MSG_EOR flag), but
1115 	 * for SOCK_STREAM we might want to improve it in future */
1116 	if (iucv->transport == AF_IUCV_TRANS_HIPER)
1117 		skb = sock_alloc_send_skb(sk,
1118 			len + sizeof(struct af_iucv_trans_hdr) + ETH_HLEN,
1119 			noblock, &err);
1120 	else
1121 		skb = sock_alloc_send_skb(sk, len, noblock, &err);
1122 	if (!skb) {
1123 		err = -ENOMEM;
1124 		goto out;
1125 	}
1126 	if (iucv->transport == AF_IUCV_TRANS_HIPER)
1127 		skb_reserve(skb, sizeof(struct af_iucv_trans_hdr) + ETH_HLEN);
1128 	if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
1129 		err = -EFAULT;
1130 		goto fail;
1131 	}
1132 
1133 	/* wait if outstanding messages for iucv path has reached */
1134 	timeo = sock_sndtimeo(sk, noblock);
1135 	err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1136 	if (err)
1137 		goto fail;
1138 
1139 	/* return -ECONNRESET if the socket is no longer connected */
1140 	if (sk->sk_state != IUCV_CONNECTED) {
1141 		err = -ECONNRESET;
1142 		goto fail;
1143 	}
1144 
1145 	/* increment and save iucv message tag for msg_completion cbk */
1146 	txmsg.tag = iucv->send_tag++;
1147 	memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);
1148 
1149 	if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1150 		atomic_inc(&iucv->msg_sent);
1151 		err = afiucv_hs_send(&txmsg, sk, skb, 0);
1152 		if (err) {
1153 			atomic_dec(&iucv->msg_sent);
1154 			goto fail;
1155 		}
1156 		goto release;
1157 	}
1158 	skb_queue_tail(&iucv->send_skb_q, skb);
1159 
1160 	if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
1161 	      && skb->len <= 7) {
1162 		err = iucv_send_iprm(iucv->path, &txmsg, skb);
1163 
1164 		/* on success: there is no message_complete callback
1165 		 * for an IPRMDATA msg; remove skb from send queue */
1166 		if (err == 0) {
1167 			skb_unlink(skb, &iucv->send_skb_q);
1168 			kfree_skb(skb);
1169 		}
1170 
1171 		/* this error should never happen since the
1172 		 * IUCV_IPRMDATA path flag is set... sever path */
1173 		if (err == 0x15) {
1174 			pr_iucv->path_sever(iucv->path, NULL);
1175 			skb_unlink(skb, &iucv->send_skb_q);
1176 			err = -EPIPE;
1177 			goto fail;
1178 		}
1179 	} else
1180 		err = pr_iucv->message_send(iucv->path, &txmsg, 0, 0,
1181 					(void *) skb->data, skb->len);
1182 	if (err) {
1183 		if (err == 3) {
1184 			user_id[8] = 0;
1185 			memcpy(user_id, iucv->dst_user_id, 8);
1186 			appl_id[8] = 0;
1187 			memcpy(appl_id, iucv->dst_name, 8);
1188 			pr_err("Application %s on z/VM guest %s"
1189 				" exceeds message limit\n",
1190 				appl_id, user_id);
1191 			err = -EAGAIN;
1192 		} else
1193 			err = -EPIPE;
1194 		skb_unlink(skb, &iucv->send_skb_q);
1195 		goto fail;
1196 	}
1197 
1198 release:
1199 	release_sock(sk);
1200 	return len;
1201 
1202 fail:
1203 	kfree_skb(skb);
1204 out:
1205 	release_sock(sk);
1206 	return err;
1207 }
1208 
1209 /* iucv_fragment_skb() - Fragment a single IUCV message into multiple skb's
1210  *
1211  * Locking: must be called with message_q.lock held
1212  */
1213 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
1214 {
1215 	int dataleft, size, copied = 0;
1216 	struct sk_buff *nskb;
1217 
1218 	dataleft = len;
1219 	while (dataleft) {
1220 		if (dataleft >= sk->sk_rcvbuf / 4)
1221 			size = sk->sk_rcvbuf / 4;
1222 		else
1223 			size = dataleft;
1224 
1225 		nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
1226 		if (!nskb)
1227 			return -ENOMEM;
1228 
1229 		/* copy target class to control buffer of new skb */
1230 		memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);
1231 
1232 		/* copy data fragment */
1233 		memcpy(nskb->data, skb->data + copied, size);
1234 		copied += size;
1235 		dataleft -= size;
1236 
1237 		skb_reset_transport_header(nskb);
1238 		skb_reset_network_header(nskb);
1239 		nskb->len = size;
1240 
1241 		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
1242 	}
1243 
1244 	return 0;
1245 }
1246 
1247 /* iucv_process_message() - Receive a single outstanding IUCV message
1248  *
1249  * Locking: must be called with message_q.lock held
1250  */
1251 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1252 				 struct iucv_path *path,
1253 				 struct iucv_message *msg)
1254 {
1255 	int rc;
1256 	unsigned int len;
1257 
1258 	len = iucv_msg_length(msg);
1259 
1260 	/* store msg target class in the second 4 bytes of skb ctrl buffer */
1261 	/* Note: the first 4 bytes are reserved for msg tag */
1262 	memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);
1263 
1264 	/* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1265 	if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1266 		if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1267 			skb->data = NULL;
1268 			skb->len = 0;
1269 		}
1270 	} else {
1271 		rc = pr_iucv->message_receive(path, msg,
1272 					      msg->flags & IUCV_IPRMDATA,
1273 					      skb->data, len, NULL);
1274 		if (rc) {
1275 			kfree_skb(skb);
1276 			return;
1277 		}
1278 		/* we need to fragment iucv messages for SOCK_STREAM only;
1279 		 * for SOCK_SEQPACKET, it is only relevant if we support
1280 		 * record segmentation using MSG_EOR (see also recvmsg()) */
1281 		if (sk->sk_type == SOCK_STREAM &&
1282 		    skb->truesize >= sk->sk_rcvbuf / 4) {
1283 			rc = iucv_fragment_skb(sk, skb, len);
1284 			kfree_skb(skb);
1285 			skb = NULL;
1286 			if (rc) {
1287 				pr_iucv->path_sever(path, NULL);
1288 				return;
1289 			}
1290 			skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
1291 		} else {
1292 			skb_reset_transport_header(skb);
1293 			skb_reset_network_header(skb);
1294 			skb->len = len;
1295 		}
1296 	}
1297 
1298 	if (sock_queue_rcv_skb(sk, skb))
1299 		skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1300 }
1301 
1302 /* iucv_process_message_q() - Process outstanding IUCV messages
1303  *
1304  * Locking: must be called with message_q.lock held
1305  */
1306 static void iucv_process_message_q(struct sock *sk)
1307 {
1308 	struct iucv_sock *iucv = iucv_sk(sk);
1309 	struct sk_buff *skb;
1310 	struct sock_msg_q *p, *n;
1311 
1312 	list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1313 		skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1314 		if (!skb)
1315 			break;
1316 		iucv_process_message(sk, skb, p->path, &p->msg);
1317 		list_del(&p->list);
1318 		kfree(p);
1319 		if (!skb_queue_empty(&iucv->backlog_skb_q))
1320 			break;
1321 	}
1322 }
1323 
1324 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1325 			     struct msghdr *msg, size_t len, int flags)
1326 {
1327 	int noblock = flags & MSG_DONTWAIT;
1328 	struct sock *sk = sock->sk;
1329 	struct iucv_sock *iucv = iucv_sk(sk);
1330 	unsigned int copied, rlen;
1331 	struct sk_buff *skb, *rskb, *cskb;
1332 	int err = 0;
1333 
1334 	if ((sk->sk_state == IUCV_DISCONN) &&
1335 	    skb_queue_empty(&iucv->backlog_skb_q) &&
1336 	    skb_queue_empty(&sk->sk_receive_queue) &&
1337 	    list_empty(&iucv->message_q.list))
1338 		return 0;
1339 
1340 	if (flags & (MSG_OOB))
1341 		return -EOPNOTSUPP;
1342 
1343 	/* receive/dequeue next skb:
1344 	 * the function understands MSG_PEEK and, thus, does not dequeue skb */
1345 	skb = skb_recv_datagram(sk, flags, noblock, &err);
1346 	if (!skb) {
1347 		if (sk->sk_shutdown & RCV_SHUTDOWN)
1348 			return 0;
1349 		return err;
1350 	}
1351 
1352 	rlen   = skb->len;		/* real length of skb */
1353 	copied = min_t(unsigned int, rlen, len);
1354 	if (!rlen)
1355 		sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1356 
1357 	cskb = skb;
1358 	if (skb_copy_datagram_iovec(cskb, 0, msg->msg_iov, copied)) {
1359 		if (!(flags & MSG_PEEK))
1360 			skb_queue_head(&sk->sk_receive_queue, skb);
1361 		return -EFAULT;
1362 	}
1363 
1364 	/* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1365 	if (sk->sk_type == SOCK_SEQPACKET) {
1366 		if (copied < rlen)
1367 			msg->msg_flags |= MSG_TRUNC;
1368 		/* each iucv message contains a complete record */
1369 		msg->msg_flags |= MSG_EOR;
1370 	}
1371 
1372 	/* create control message to store iucv msg target class:
1373 	 * get the trgcls from the control buffer of the skb due to
1374 	 * fragmentation of original iucv message. */
1375 	err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1376 			CB_TRGCLS_LEN, CB_TRGCLS(skb));
1377 	if (err) {
1378 		if (!(flags & MSG_PEEK))
1379 			skb_queue_head(&sk->sk_receive_queue, skb);
1380 		return err;
1381 	}
1382 
1383 	/* Mark read part of skb as used */
1384 	if (!(flags & MSG_PEEK)) {
1385 
1386 		/* SOCK_STREAM: re-queue skb if it contains unreceived data */
1387 		if (sk->sk_type == SOCK_STREAM) {
1388 			skb_pull(skb, copied);
1389 			if (skb->len) {
1390 				skb_queue_head(&sk->sk_receive_queue, skb);
1391 				goto done;
1392 			}
1393 		}
1394 
1395 		kfree_skb(skb);
1396 		if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1397 			atomic_inc(&iucv->msg_recv);
1398 			if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1399 				WARN_ON(1);
1400 				iucv_sock_close(sk);
1401 				return -EFAULT;
1402 			}
1403 		}
1404 
1405 		/* Queue backlog skbs */
1406 		spin_lock_bh(&iucv->message_q.lock);
1407 		rskb = skb_dequeue(&iucv->backlog_skb_q);
1408 		while (rskb) {
1409 			if (sock_queue_rcv_skb(sk, rskb)) {
1410 				skb_queue_head(&iucv->backlog_skb_q,
1411 						rskb);
1412 				break;
1413 			} else {
1414 				rskb = skb_dequeue(&iucv->backlog_skb_q);
1415 			}
1416 		}
1417 		if (skb_queue_empty(&iucv->backlog_skb_q)) {
1418 			if (!list_empty(&iucv->message_q.list))
1419 				iucv_process_message_q(sk);
1420 			if (atomic_read(&iucv->msg_recv) >=
1421 							iucv->msglimit / 2) {
1422 				err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1423 				if (err) {
1424 					sk->sk_state = IUCV_DISCONN;
1425 					sk->sk_state_change(sk);
1426 				}
1427 			}
1428 		}
1429 		spin_unlock_bh(&iucv->message_q.lock);
1430 	}
1431 
1432 done:
1433 	/* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1434 	if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1435 		copied = rlen;
1436 
1437 	return copied;
1438 }
1439 
1440 static inline unsigned int iucv_accept_poll(struct sock *parent)
1441 {
1442 	struct iucv_sock *isk, *n;
1443 	struct sock *sk;
1444 
1445 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1446 		sk = (struct sock *) isk;
1447 
1448 		if (sk->sk_state == IUCV_CONNECTED)
1449 			return POLLIN | POLLRDNORM;
1450 	}
1451 
1452 	return 0;
1453 }
1454 
1455 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1456 			    poll_table *wait)
1457 {
1458 	struct sock *sk = sock->sk;
1459 	unsigned int mask = 0;
1460 
1461 	sock_poll_wait(file, sk_sleep(sk), wait);
1462 
1463 	if (sk->sk_state == IUCV_LISTEN)
1464 		return iucv_accept_poll(sk);
1465 
1466 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1467 		mask |= POLLERR;
1468 
1469 	if (sk->sk_shutdown & RCV_SHUTDOWN)
1470 		mask |= POLLRDHUP;
1471 
1472 	if (sk->sk_shutdown == SHUTDOWN_MASK)
1473 		mask |= POLLHUP;
1474 
1475 	if (!skb_queue_empty(&sk->sk_receive_queue) ||
1476 	    (sk->sk_shutdown & RCV_SHUTDOWN))
1477 		mask |= POLLIN | POLLRDNORM;
1478 
1479 	if (sk->sk_state == IUCV_CLOSED)
1480 		mask |= POLLHUP;
1481 
1482 	if (sk->sk_state == IUCV_DISCONN)
1483 		mask |= POLLIN;
1484 
1485 	if (sock_writeable(sk) && iucv_below_msglim(sk))
1486 		mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1487 	else
1488 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1489 
1490 	return mask;
1491 }
1492 
1493 static int iucv_sock_shutdown(struct socket *sock, int how)
1494 {
1495 	struct sock *sk = sock->sk;
1496 	struct iucv_sock *iucv = iucv_sk(sk);
1497 	struct iucv_message txmsg;
1498 	int err = 0;
1499 
1500 	how++;
1501 
1502 	if ((how & ~SHUTDOWN_MASK) || !how)
1503 		return -EINVAL;
1504 
1505 	lock_sock(sk);
1506 	switch (sk->sk_state) {
1507 	case IUCV_LISTEN:
1508 	case IUCV_DISCONN:
1509 	case IUCV_CLOSING:
1510 	case IUCV_CLOSED:
1511 		err = -ENOTCONN;
1512 		goto fail;
1513 	default:
1514 		break;
1515 	}
1516 
1517 	if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1518 		if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1519 			txmsg.class = 0;
1520 			txmsg.tag = 0;
1521 			err = pr_iucv->message_send(iucv->path, &txmsg,
1522 				IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1523 			if (err) {
1524 				switch (err) {
1525 				case 1:
1526 					err = -ENOTCONN;
1527 					break;
1528 				case 2:
1529 					err = -ECONNRESET;
1530 					break;
1531 				default:
1532 					err = -ENOTCONN;
1533 					break;
1534 				}
1535 			}
1536 		} else
1537 			iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1538 	}
1539 
1540 	sk->sk_shutdown |= how;
1541 	if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1542 		if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1543 			err = pr_iucv->path_quiesce(iucv->path, NULL);
1544 			if (err)
1545 				err = -ENOTCONN;
1546 /*			skb_queue_purge(&sk->sk_receive_queue); */
1547 		}
1548 		skb_queue_purge(&sk->sk_receive_queue);
1549 	}
1550 
1551 	/* Wake up anyone sleeping in poll */
1552 	sk->sk_state_change(sk);
1553 
1554 fail:
1555 	release_sock(sk);
1556 	return err;
1557 }
1558 
1559 static int iucv_sock_release(struct socket *sock)
1560 {
1561 	struct sock *sk = sock->sk;
1562 	int err = 0;
1563 
1564 	if (!sk)
1565 		return 0;
1566 
1567 	iucv_sock_close(sk);
1568 
1569 	sock_orphan(sk);
1570 	iucv_sock_kill(sk);
1571 	return err;
1572 }
1573 
1574 /* getsockopt and setsockopt */
1575 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1576 				char __user *optval, unsigned int optlen)
1577 {
1578 	struct sock *sk = sock->sk;
1579 	struct iucv_sock *iucv = iucv_sk(sk);
1580 	int val;
1581 	int rc;
1582 
1583 	if (level != SOL_IUCV)
1584 		return -ENOPROTOOPT;
1585 
1586 	if (optlen < sizeof(int))
1587 		return -EINVAL;
1588 
1589 	if (get_user(val, (int __user *) optval))
1590 		return -EFAULT;
1591 
1592 	rc = 0;
1593 
1594 	lock_sock(sk);
1595 	switch (optname) {
1596 	case SO_IPRMDATA_MSG:
1597 		if (val)
1598 			iucv->flags |= IUCV_IPRMDATA;
1599 		else
1600 			iucv->flags &= ~IUCV_IPRMDATA;
1601 		break;
1602 	case SO_MSGLIMIT:
1603 		switch (sk->sk_state) {
1604 		case IUCV_OPEN:
1605 		case IUCV_BOUND:
1606 			if (val < 1 || val > (u16)(~0))
1607 				rc = -EINVAL;
1608 			else
1609 				iucv->msglimit = val;
1610 			break;
1611 		default:
1612 			rc = -EINVAL;
1613 			break;
1614 		}
1615 		break;
1616 	default:
1617 		rc = -ENOPROTOOPT;
1618 		break;
1619 	}
1620 	release_sock(sk);
1621 
1622 	return rc;
1623 }
1624 
1625 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1626 				char __user *optval, int __user *optlen)
1627 {
1628 	struct sock *sk = sock->sk;
1629 	struct iucv_sock *iucv = iucv_sk(sk);
1630 	unsigned int val;
1631 	int len;
1632 
1633 	if (level != SOL_IUCV)
1634 		return -ENOPROTOOPT;
1635 
1636 	if (get_user(len, optlen))
1637 		return -EFAULT;
1638 
1639 	if (len < 0)
1640 		return -EINVAL;
1641 
1642 	len = min_t(unsigned int, len, sizeof(int));
1643 
1644 	switch (optname) {
1645 	case SO_IPRMDATA_MSG:
1646 		val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1647 		break;
1648 	case SO_MSGLIMIT:
1649 		lock_sock(sk);
1650 		val = (iucv->path != NULL) ? iucv->path->msglim	/* connected */
1651 					   : iucv->msglimit;	/* default */
1652 		release_sock(sk);
1653 		break;
1654 	case SO_MSGSIZE:
1655 		if (sk->sk_state == IUCV_OPEN)
1656 			return -EBADFD;
1657 		val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1658 				sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1659 				0x7fffffff;
1660 		break;
1661 	default:
1662 		return -ENOPROTOOPT;
1663 	}
1664 
1665 	if (put_user(len, optlen))
1666 		return -EFAULT;
1667 	if (copy_to_user(optval, &val, len))
1668 		return -EFAULT;
1669 
1670 	return 0;
1671 }
1672 
1673 
1674 /* Callback wrappers - called from iucv base support */
1675 static int iucv_callback_connreq(struct iucv_path *path,
1676 				 u8 ipvmid[8], u8 ipuser[16])
1677 {
1678 	unsigned char user_data[16];
1679 	unsigned char nuser_data[16];
1680 	unsigned char src_name[8];
1681 	struct hlist_node *node;
1682 	struct sock *sk, *nsk;
1683 	struct iucv_sock *iucv, *niucv;
1684 	int err;
1685 
1686 	memcpy(src_name, ipuser, 8);
1687 	EBCASC(src_name, 8);
1688 	/* Find out if this path belongs to af_iucv. */
1689 	read_lock(&iucv_sk_list.lock);
1690 	iucv = NULL;
1691 	sk = NULL;
1692 	sk_for_each(sk, node, &iucv_sk_list.head)
1693 		if (sk->sk_state == IUCV_LISTEN &&
1694 		    !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1695 			/*
1696 			 * Found a listening socket with
1697 			 * src_name == ipuser[0-7].
1698 			 */
1699 			iucv = iucv_sk(sk);
1700 			break;
1701 		}
1702 	read_unlock(&iucv_sk_list.lock);
1703 	if (!iucv)
1704 		/* No socket found, not one of our paths. */
1705 		return -EINVAL;
1706 
1707 	bh_lock_sock(sk);
1708 
1709 	/* Check if parent socket is listening */
1710 	low_nmcpy(user_data, iucv->src_name);
1711 	high_nmcpy(user_data, iucv->dst_name);
1712 	ASCEBC(user_data, sizeof(user_data));
1713 	if (sk->sk_state != IUCV_LISTEN) {
1714 		err = pr_iucv->path_sever(path, user_data);
1715 		iucv_path_free(path);
1716 		goto fail;
1717 	}
1718 
1719 	/* Check for backlog size */
1720 	if (sk_acceptq_is_full(sk)) {
1721 		err = pr_iucv->path_sever(path, user_data);
1722 		iucv_path_free(path);
1723 		goto fail;
1724 	}
1725 
1726 	/* Create the new socket */
1727 	nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1728 	if (!nsk) {
1729 		err = pr_iucv->path_sever(path, user_data);
1730 		iucv_path_free(path);
1731 		goto fail;
1732 	}
1733 
1734 	niucv = iucv_sk(nsk);
1735 	iucv_sock_init(nsk, sk);
1736 
1737 	/* Set the new iucv_sock */
1738 	memcpy(niucv->dst_name, ipuser + 8, 8);
1739 	EBCASC(niucv->dst_name, 8);
1740 	memcpy(niucv->dst_user_id, ipvmid, 8);
1741 	memcpy(niucv->src_name, iucv->src_name, 8);
1742 	memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1743 	niucv->path = path;
1744 
1745 	/* Call iucv_accept */
1746 	high_nmcpy(nuser_data, ipuser + 8);
1747 	memcpy(nuser_data + 8, niucv->src_name, 8);
1748 	ASCEBC(nuser_data + 8, 8);
1749 
1750 	/* set message limit for path based on msglimit of accepting socket */
1751 	niucv->msglimit = iucv->msglimit;
1752 	path->msglim = iucv->msglimit;
1753 	err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1754 	if (err) {
1755 		iucv_sever_path(nsk, 1);
1756 		iucv_sock_kill(nsk);
1757 		goto fail;
1758 	}
1759 
1760 	iucv_accept_enqueue(sk, nsk);
1761 
1762 	/* Wake up accept */
1763 	nsk->sk_state = IUCV_CONNECTED;
1764 	sk->sk_data_ready(sk, 1);
1765 	err = 0;
1766 fail:
1767 	bh_unlock_sock(sk);
1768 	return 0;
1769 }
1770 
1771 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1772 {
1773 	struct sock *sk = path->private;
1774 
1775 	sk->sk_state = IUCV_CONNECTED;
1776 	sk->sk_state_change(sk);
1777 }
1778 
1779 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1780 {
1781 	struct sock *sk = path->private;
1782 	struct iucv_sock *iucv = iucv_sk(sk);
1783 	struct sk_buff *skb;
1784 	struct sock_msg_q *save_msg;
1785 	int len;
1786 
1787 	if (sk->sk_shutdown & RCV_SHUTDOWN) {
1788 		pr_iucv->message_reject(path, msg);
1789 		return;
1790 	}
1791 
1792 	spin_lock(&iucv->message_q.lock);
1793 
1794 	if (!list_empty(&iucv->message_q.list) ||
1795 	    !skb_queue_empty(&iucv->backlog_skb_q))
1796 		goto save_message;
1797 
1798 	len = atomic_read(&sk->sk_rmem_alloc);
1799 	len += SKB_TRUESIZE(iucv_msg_length(msg));
1800 	if (len > sk->sk_rcvbuf)
1801 		goto save_message;
1802 
1803 	skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1804 	if (!skb)
1805 		goto save_message;
1806 
1807 	iucv_process_message(sk, skb, path, msg);
1808 	goto out_unlock;
1809 
1810 save_message:
1811 	save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1812 	if (!save_msg)
1813 		goto out_unlock;
1814 	save_msg->path = path;
1815 	save_msg->msg = *msg;
1816 
1817 	list_add_tail(&save_msg->list, &iucv->message_q.list);
1818 
1819 out_unlock:
1820 	spin_unlock(&iucv->message_q.lock);
1821 }
1822 
1823 static void iucv_callback_txdone(struct iucv_path *path,
1824 				 struct iucv_message *msg)
1825 {
1826 	struct sock *sk = path->private;
1827 	struct sk_buff *this = NULL;
1828 	struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1829 	struct sk_buff *list_skb = list->next;
1830 	unsigned long flags;
1831 
1832 	bh_lock_sock(sk);
1833 	if (!skb_queue_empty(list)) {
1834 		spin_lock_irqsave(&list->lock, flags);
1835 
1836 		while (list_skb != (struct sk_buff *)list) {
1837 			if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {
1838 				this = list_skb;
1839 				break;
1840 			}
1841 			list_skb = list_skb->next;
1842 		}
1843 		if (this)
1844 			__skb_unlink(this, list);
1845 
1846 		spin_unlock_irqrestore(&list->lock, flags);
1847 
1848 		if (this) {
1849 			kfree_skb(this);
1850 			/* wake up any process waiting for sending */
1851 			iucv_sock_wake_msglim(sk);
1852 		}
1853 	}
1854 
1855 	if (sk->sk_state == IUCV_CLOSING) {
1856 		if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1857 			sk->sk_state = IUCV_CLOSED;
1858 			sk->sk_state_change(sk);
1859 		}
1860 	}
1861 	bh_unlock_sock(sk);
1862 
1863 }
1864 
1865 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1866 {
1867 	struct sock *sk = path->private;
1868 
1869 	if (sk->sk_state == IUCV_CLOSED)
1870 		return;
1871 
1872 	bh_lock_sock(sk);
1873 	iucv_sever_path(sk, 1);
1874 	sk->sk_state = IUCV_DISCONN;
1875 
1876 	sk->sk_state_change(sk);
1877 	bh_unlock_sock(sk);
1878 }
1879 
1880 /* called if the other communication side shuts down its RECV direction;
1881  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1882  */
1883 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1884 {
1885 	struct sock *sk = path->private;
1886 
1887 	bh_lock_sock(sk);
1888 	if (sk->sk_state != IUCV_CLOSED) {
1889 		sk->sk_shutdown |= SEND_SHUTDOWN;
1890 		sk->sk_state_change(sk);
1891 	}
1892 	bh_unlock_sock(sk);
1893 }
1894 
1895 /***************** HiperSockets transport callbacks ********************/
1896 static void afiucv_swap_src_dest(struct sk_buff *skb)
1897 {
1898 	struct af_iucv_trans_hdr *trans_hdr =
1899 				(struct af_iucv_trans_hdr *)skb->data;
1900 	char tmpID[8];
1901 	char tmpName[8];
1902 
1903 	ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1904 	ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1905 	ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1906 	ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1907 	memcpy(tmpID, trans_hdr->srcUserID, 8);
1908 	memcpy(tmpName, trans_hdr->srcAppName, 8);
1909 	memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1910 	memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1911 	memcpy(trans_hdr->destUserID, tmpID, 8);
1912 	memcpy(trans_hdr->destAppName, tmpName, 8);
1913 	skb_push(skb, ETH_HLEN);
1914 	memset(skb->data, 0, ETH_HLEN);
1915 }
1916 
1917 /**
1918  * afiucv_hs_callback_syn - react on received SYN
1919  **/
1920 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1921 {
1922 	struct sock *nsk;
1923 	struct iucv_sock *iucv, *niucv;
1924 	struct af_iucv_trans_hdr *trans_hdr;
1925 	int err;
1926 
1927 	iucv = iucv_sk(sk);
1928 	trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
1929 	if (!iucv) {
1930 		/* no sock - connection refused */
1931 		afiucv_swap_src_dest(skb);
1932 		trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1933 		err = dev_queue_xmit(skb);
1934 		goto out;
1935 	}
1936 
1937 	nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1938 	bh_lock_sock(sk);
1939 	if ((sk->sk_state != IUCV_LISTEN) ||
1940 	    sk_acceptq_is_full(sk) ||
1941 	    !nsk) {
1942 		/* error on server socket - connection refused */
1943 		if (nsk)
1944 			sk_free(nsk);
1945 		afiucv_swap_src_dest(skb);
1946 		trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1947 		err = dev_queue_xmit(skb);
1948 		bh_unlock_sock(sk);
1949 		goto out;
1950 	}
1951 
1952 	niucv = iucv_sk(nsk);
1953 	iucv_sock_init(nsk, sk);
1954 	niucv->transport = AF_IUCV_TRANS_HIPER;
1955 	niucv->msglimit = iucv->msglimit;
1956 	if (!trans_hdr->window)
1957 		niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1958 	else
1959 		niucv->msglimit_peer = trans_hdr->window;
1960 	memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
1961 	memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
1962 	memcpy(niucv->src_name, iucv->src_name, 8);
1963 	memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1964 	nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
1965 	niucv->hs_dev = iucv->hs_dev;
1966 	dev_hold(niucv->hs_dev);
1967 	afiucv_swap_src_dest(skb);
1968 	trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
1969 	trans_hdr->window = niucv->msglimit;
1970 	/* if receiver acks the xmit connection is established */
1971 	err = dev_queue_xmit(skb);
1972 	if (!err) {
1973 		iucv_accept_enqueue(sk, nsk);
1974 		nsk->sk_state = IUCV_CONNECTED;
1975 		sk->sk_data_ready(sk, 1);
1976 	} else
1977 		iucv_sock_kill(nsk);
1978 	bh_unlock_sock(sk);
1979 
1980 out:
1981 	return NET_RX_SUCCESS;
1982 }
1983 
1984 /**
1985  * afiucv_hs_callback_synack() - react on received SYN-ACK
1986  **/
1987 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
1988 {
1989 	struct iucv_sock *iucv = iucv_sk(sk);
1990 	struct af_iucv_trans_hdr *trans_hdr =
1991 					(struct af_iucv_trans_hdr *)skb->data;
1992 
1993 	if (!iucv)
1994 		goto out;
1995 	if (sk->sk_state != IUCV_BOUND)
1996 		goto out;
1997 	bh_lock_sock(sk);
1998 	iucv->msglimit_peer = trans_hdr->window;
1999 	sk->sk_state = IUCV_CONNECTED;
2000 	sk->sk_state_change(sk);
2001 	bh_unlock_sock(sk);
2002 out:
2003 	kfree_skb(skb);
2004 	return NET_RX_SUCCESS;
2005 }
2006 
2007 /**
2008  * afiucv_hs_callback_synfin() - react on received SYN_FIN
2009  **/
2010 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2011 {
2012 	struct iucv_sock *iucv = iucv_sk(sk);
2013 
2014 	if (!iucv)
2015 		goto out;
2016 	if (sk->sk_state != IUCV_BOUND)
2017 		goto out;
2018 	bh_lock_sock(sk);
2019 	sk->sk_state = IUCV_DISCONN;
2020 	sk->sk_state_change(sk);
2021 	bh_unlock_sock(sk);
2022 out:
2023 	kfree_skb(skb);
2024 	return NET_RX_SUCCESS;
2025 }
2026 
2027 /**
2028  * afiucv_hs_callback_fin() - react on received FIN
2029  **/
2030 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2031 {
2032 	struct iucv_sock *iucv = iucv_sk(sk);
2033 
2034 	/* other end of connection closed */
2035 	if (!iucv)
2036 		goto out;
2037 	bh_lock_sock(sk);
2038 	if (sk->sk_state == IUCV_CONNECTED) {
2039 		sk->sk_state = IUCV_DISCONN;
2040 		sk->sk_state_change(sk);
2041 	}
2042 	bh_unlock_sock(sk);
2043 out:
2044 	kfree_skb(skb);
2045 	return NET_RX_SUCCESS;
2046 }
2047 
2048 /**
2049  * afiucv_hs_callback_win() - react on received WIN
2050  **/
2051 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2052 {
2053 	struct iucv_sock *iucv = iucv_sk(sk);
2054 	struct af_iucv_trans_hdr *trans_hdr =
2055 					(struct af_iucv_trans_hdr *)skb->data;
2056 
2057 	if (!iucv)
2058 		return NET_RX_SUCCESS;
2059 
2060 	if (sk->sk_state != IUCV_CONNECTED)
2061 		return NET_RX_SUCCESS;
2062 
2063 	atomic_sub(trans_hdr->window, &iucv->msg_sent);
2064 	iucv_sock_wake_msglim(sk);
2065 	return NET_RX_SUCCESS;
2066 }
2067 
2068 /**
2069  * afiucv_hs_callback_rx() - react on received data
2070  **/
2071 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2072 {
2073 	struct iucv_sock *iucv = iucv_sk(sk);
2074 
2075 	if (!iucv) {
2076 		kfree_skb(skb);
2077 		return NET_RX_SUCCESS;
2078 	}
2079 
2080 	if (sk->sk_state != IUCV_CONNECTED) {
2081 		kfree_skb(skb);
2082 		return NET_RX_SUCCESS;
2083 	}
2084 
2085 	if (sk->sk_shutdown & RCV_SHUTDOWN) {
2086 		kfree_skb(skb);
2087 		return NET_RX_SUCCESS;
2088 	}
2089 
2090 		/* write stuff from iucv_msg to skb cb */
2091 	if (skb->len < sizeof(struct af_iucv_trans_hdr)) {
2092 		kfree_skb(skb);
2093 		return NET_RX_SUCCESS;
2094 	}
2095 	skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2096 	skb_reset_transport_header(skb);
2097 	skb_reset_network_header(skb);
2098 	spin_lock(&iucv->message_q.lock);
2099 	if (skb_queue_empty(&iucv->backlog_skb_q)) {
2100 		if (sock_queue_rcv_skb(sk, skb)) {
2101 			/* handle rcv queue full */
2102 			skb_queue_tail(&iucv->backlog_skb_q, skb);
2103 		}
2104 	} else
2105 		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2106 	spin_unlock(&iucv->message_q.lock);
2107 	return NET_RX_SUCCESS;
2108 }
2109 
2110 /**
2111  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2112  *                   transport
2113  *                   called from netif RX softirq
2114  **/
2115 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2116 	struct packet_type *pt, struct net_device *orig_dev)
2117 {
2118 	struct hlist_node *node;
2119 	struct sock *sk;
2120 	struct iucv_sock *iucv;
2121 	struct af_iucv_trans_hdr *trans_hdr;
2122 	char nullstring[8];
2123 	int err = 0;
2124 
2125 	skb_pull(skb, ETH_HLEN);
2126 	trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
2127 	EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2128 	EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2129 	EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2130 	EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2131 	memset(nullstring, 0, sizeof(nullstring));
2132 	iucv = NULL;
2133 	sk = NULL;
2134 	read_lock(&iucv_sk_list.lock);
2135 	sk_for_each(sk, node, &iucv_sk_list.head) {
2136 		if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2137 			if ((!memcmp(&iucv_sk(sk)->src_name,
2138 				     trans_hdr->destAppName, 8)) &&
2139 			    (!memcmp(&iucv_sk(sk)->src_user_id,
2140 				     trans_hdr->destUserID, 8)) &&
2141 			    (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2142 			    (!memcmp(&iucv_sk(sk)->dst_user_id,
2143 				     nullstring, 8))) {
2144 				iucv = iucv_sk(sk);
2145 				break;
2146 			}
2147 		} else {
2148 			if ((!memcmp(&iucv_sk(sk)->src_name,
2149 				     trans_hdr->destAppName, 8)) &&
2150 			    (!memcmp(&iucv_sk(sk)->src_user_id,
2151 				     trans_hdr->destUserID, 8)) &&
2152 			    (!memcmp(&iucv_sk(sk)->dst_name,
2153 				     trans_hdr->srcAppName, 8)) &&
2154 			    (!memcmp(&iucv_sk(sk)->dst_user_id,
2155 				     trans_hdr->srcUserID, 8))) {
2156 				iucv = iucv_sk(sk);
2157 				break;
2158 			}
2159 		}
2160 	}
2161 	read_unlock(&iucv_sk_list.lock);
2162 	if (!iucv)
2163 		sk = NULL;
2164 
2165 	/* no sock
2166 	how should we send with no sock
2167 	1) send without sock no send rc checking?
2168 	2) introduce default sock to handle this cases
2169 
2170 	 SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2171 	 data -> send FIN
2172 	 SYN|ACK, SYN|FIN, FIN -> no action? */
2173 
2174 	switch (trans_hdr->flags) {
2175 	case AF_IUCV_FLAG_SYN:
2176 		/* connect request */
2177 		err = afiucv_hs_callback_syn(sk, skb);
2178 		break;
2179 	case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2180 		/* connect request confirmed */
2181 		err = afiucv_hs_callback_synack(sk, skb);
2182 		break;
2183 	case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2184 		/* connect request refused */
2185 		err = afiucv_hs_callback_synfin(sk, skb);
2186 		break;
2187 	case (AF_IUCV_FLAG_FIN):
2188 		/* close request */
2189 		err = afiucv_hs_callback_fin(sk, skb);
2190 		break;
2191 	case (AF_IUCV_FLAG_WIN):
2192 		err = afiucv_hs_callback_win(sk, skb);
2193 		if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2194 			kfree_skb(skb);
2195 			break;
2196 		}
2197 		/* fall through and receive non-zero length data */
2198 	case (AF_IUCV_FLAG_SHT):
2199 		/* shutdown request */
2200 		/* fall through and receive zero length data */
2201 	case 0:
2202 		/* plain data frame */
2203 		memcpy(CB_TRGCLS(skb), &trans_hdr->iucv_hdr.class,
2204 		       CB_TRGCLS_LEN);
2205 		err = afiucv_hs_callback_rx(sk, skb);
2206 		break;
2207 	default:
2208 		;
2209 	}
2210 
2211 	return err;
2212 }
2213 
2214 /**
2215  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2216  *                                 transport
2217  **/
2218 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2219 					enum iucv_tx_notify n)
2220 {
2221 	struct sock *isk = skb->sk;
2222 	struct sock *sk = NULL;
2223 	struct iucv_sock *iucv = NULL;
2224 	struct sk_buff_head *list;
2225 	struct sk_buff *list_skb;
2226 	struct sk_buff *nskb;
2227 	unsigned long flags;
2228 	struct hlist_node *node;
2229 
2230 	read_lock_irqsave(&iucv_sk_list.lock, flags);
2231 	sk_for_each(sk, node, &iucv_sk_list.head)
2232 		if (sk == isk) {
2233 			iucv = iucv_sk(sk);
2234 			break;
2235 		}
2236 	read_unlock_irqrestore(&iucv_sk_list.lock, flags);
2237 
2238 	if (!iucv || sock_flag(sk, SOCK_ZAPPED))
2239 		return;
2240 
2241 	list = &iucv->send_skb_q;
2242 	spin_lock_irqsave(&list->lock, flags);
2243 	if (skb_queue_empty(list))
2244 		goto out_unlock;
2245 	list_skb = list->next;
2246 	nskb = list_skb->next;
2247 	while (list_skb != (struct sk_buff *)list) {
2248 		if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2249 			switch (n) {
2250 			case TX_NOTIFY_OK:
2251 				__skb_unlink(list_skb, list);
2252 				kfree_skb(list_skb);
2253 				iucv_sock_wake_msglim(sk);
2254 				break;
2255 			case TX_NOTIFY_PENDING:
2256 				atomic_inc(&iucv->pendings);
2257 				break;
2258 			case TX_NOTIFY_DELAYED_OK:
2259 				__skb_unlink(list_skb, list);
2260 				atomic_dec(&iucv->pendings);
2261 				if (atomic_read(&iucv->pendings) <= 0)
2262 					iucv_sock_wake_msglim(sk);
2263 				kfree_skb(list_skb);
2264 				break;
2265 			case TX_NOTIFY_UNREACHABLE:
2266 			case TX_NOTIFY_DELAYED_UNREACHABLE:
2267 			case TX_NOTIFY_TPQFULL: /* not yet used */
2268 			case TX_NOTIFY_GENERALERROR:
2269 			case TX_NOTIFY_DELAYED_GENERALERROR:
2270 				__skb_unlink(list_skb, list);
2271 				kfree_skb(list_skb);
2272 				if (sk->sk_state == IUCV_CONNECTED) {
2273 					sk->sk_state = IUCV_DISCONN;
2274 					sk->sk_state_change(sk);
2275 				}
2276 				break;
2277 			}
2278 			break;
2279 		}
2280 		list_skb = nskb;
2281 		nskb = nskb->next;
2282 	}
2283 out_unlock:
2284 	spin_unlock_irqrestore(&list->lock, flags);
2285 
2286 	if (sk->sk_state == IUCV_CLOSING) {
2287 		if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
2288 			sk->sk_state = IUCV_CLOSED;
2289 			sk->sk_state_change(sk);
2290 		}
2291 	}
2292 
2293 }
2294 
2295 /*
2296  * afiucv_netdev_event: handle netdev notifier chain events
2297  */
2298 static int afiucv_netdev_event(struct notifier_block *this,
2299 			       unsigned long event, void *ptr)
2300 {
2301 	struct net_device *event_dev = (struct net_device *)ptr;
2302 	struct hlist_node *node;
2303 	struct sock *sk;
2304 	struct iucv_sock *iucv;
2305 
2306 	switch (event) {
2307 	case NETDEV_REBOOT:
2308 	case NETDEV_GOING_DOWN:
2309 		sk_for_each(sk, node, &iucv_sk_list.head) {
2310 			iucv = iucv_sk(sk);
2311 			if ((iucv->hs_dev == event_dev) &&
2312 			    (sk->sk_state == IUCV_CONNECTED)) {
2313 				if (event == NETDEV_GOING_DOWN)
2314 					iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2315 				sk->sk_state = IUCV_DISCONN;
2316 				sk->sk_state_change(sk);
2317 			}
2318 		}
2319 		break;
2320 	case NETDEV_DOWN:
2321 	case NETDEV_UNREGISTER:
2322 	default:
2323 		break;
2324 	}
2325 	return NOTIFY_DONE;
2326 }
2327 
2328 static struct notifier_block afiucv_netdev_notifier = {
2329 	.notifier_call = afiucv_netdev_event,
2330 };
2331 
2332 static const struct proto_ops iucv_sock_ops = {
2333 	.family		= PF_IUCV,
2334 	.owner		= THIS_MODULE,
2335 	.release	= iucv_sock_release,
2336 	.bind		= iucv_sock_bind,
2337 	.connect	= iucv_sock_connect,
2338 	.listen		= iucv_sock_listen,
2339 	.accept		= iucv_sock_accept,
2340 	.getname	= iucv_sock_getname,
2341 	.sendmsg	= iucv_sock_sendmsg,
2342 	.recvmsg	= iucv_sock_recvmsg,
2343 	.poll		= iucv_sock_poll,
2344 	.ioctl		= sock_no_ioctl,
2345 	.mmap		= sock_no_mmap,
2346 	.socketpair	= sock_no_socketpair,
2347 	.shutdown	= iucv_sock_shutdown,
2348 	.setsockopt	= iucv_sock_setsockopt,
2349 	.getsockopt	= iucv_sock_getsockopt,
2350 };
2351 
2352 static const struct net_proto_family iucv_sock_family_ops = {
2353 	.family	= AF_IUCV,
2354 	.owner	= THIS_MODULE,
2355 	.create	= iucv_sock_create,
2356 };
2357 
2358 static struct packet_type iucv_packet_type = {
2359 	.type = cpu_to_be16(ETH_P_AF_IUCV),
2360 	.func = afiucv_hs_rcv,
2361 };
2362 
2363 static int afiucv_iucv_init(void)
2364 {
2365 	int err;
2366 
2367 	err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2368 	if (err)
2369 		goto out;
2370 	/* establish dummy device */
2371 	af_iucv_driver.bus = pr_iucv->bus;
2372 	err = driver_register(&af_iucv_driver);
2373 	if (err)
2374 		goto out_iucv;
2375 	af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2376 	if (!af_iucv_dev) {
2377 		err = -ENOMEM;
2378 		goto out_driver;
2379 	}
2380 	dev_set_name(af_iucv_dev, "af_iucv");
2381 	af_iucv_dev->bus = pr_iucv->bus;
2382 	af_iucv_dev->parent = pr_iucv->root;
2383 	af_iucv_dev->release = (void (*)(struct device *))kfree;
2384 	af_iucv_dev->driver = &af_iucv_driver;
2385 	err = device_register(af_iucv_dev);
2386 	if (err)
2387 		goto out_driver;
2388 	return 0;
2389 
2390 out_driver:
2391 	driver_unregister(&af_iucv_driver);
2392 out_iucv:
2393 	pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2394 out:
2395 	return err;
2396 }
2397 
2398 static int __init afiucv_init(void)
2399 {
2400 	int err;
2401 
2402 	if (MACHINE_IS_VM) {
2403 		cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2404 		if (unlikely(err)) {
2405 			WARN_ON(err);
2406 			err = -EPROTONOSUPPORT;
2407 			goto out;
2408 		}
2409 
2410 		pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2411 		if (!pr_iucv) {
2412 			printk(KERN_WARNING "iucv_if lookup failed\n");
2413 			memset(&iucv_userid, 0, sizeof(iucv_userid));
2414 		}
2415 	} else {
2416 		memset(&iucv_userid, 0, sizeof(iucv_userid));
2417 		pr_iucv = NULL;
2418 	}
2419 
2420 	err = proto_register(&iucv_proto, 0);
2421 	if (err)
2422 		goto out;
2423 	err = sock_register(&iucv_sock_family_ops);
2424 	if (err)
2425 		goto out_proto;
2426 
2427 	if (pr_iucv) {
2428 		err = afiucv_iucv_init();
2429 		if (err)
2430 			goto out_sock;
2431 	} else
2432 		register_netdevice_notifier(&afiucv_netdev_notifier);
2433 	dev_add_pack(&iucv_packet_type);
2434 	return 0;
2435 
2436 out_sock:
2437 	sock_unregister(PF_IUCV);
2438 out_proto:
2439 	proto_unregister(&iucv_proto);
2440 out:
2441 	if (pr_iucv)
2442 		symbol_put(iucv_if);
2443 	return err;
2444 }
2445 
2446 static void __exit afiucv_exit(void)
2447 {
2448 	if (pr_iucv) {
2449 		device_unregister(af_iucv_dev);
2450 		driver_unregister(&af_iucv_driver);
2451 		pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2452 		symbol_put(iucv_if);
2453 	} else
2454 		unregister_netdevice_notifier(&afiucv_netdev_notifier);
2455 	dev_remove_pack(&iucv_packet_type);
2456 	sock_unregister(PF_IUCV);
2457 	proto_unregister(&iucv_proto);
2458 }
2459 
2460 module_init(afiucv_init);
2461 module_exit(afiucv_exit);
2462 
2463 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2464 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2465 MODULE_VERSION(VERSION);
2466 MODULE_LICENSE("GPL");
2467 MODULE_ALIAS_NETPROTO(PF_IUCV);
2468 
2469