xref: /openbmc/linux/net/iucv/af_iucv.c (revision 1c2f87c2)
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 #define __iucv_sock_wait(sk, condition, timeo, ret)			\
53 do {									\
54 	DEFINE_WAIT(__wait);						\
55 	long __timeo = timeo;						\
56 	ret = 0;							\
57 	prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE);	\
58 	while (!(condition)) {						\
59 		if (!__timeo) {						\
60 			ret = -EAGAIN;					\
61 			break;						\
62 		}							\
63 		if (signal_pending(current)) {				\
64 			ret = sock_intr_errno(__timeo);			\
65 			break;						\
66 		}							\
67 		release_sock(sk);					\
68 		__timeo = schedule_timeout(__timeo);			\
69 		lock_sock(sk);						\
70 		ret = sock_error(sk);					\
71 		if (ret)						\
72 			break;						\
73 	}								\
74 	finish_wait(sk_sleep(sk), &__wait);				\
75 } while (0)
76 
77 #define iucv_sock_wait(sk, condition, timeo)				\
78 ({									\
79 	int __ret = 0;							\
80 	if (!(condition))						\
81 		__iucv_sock_wait(sk, condition, timeo, __ret);		\
82 	__ret;								\
83 })
84 
85 static void iucv_sock_kill(struct sock *sk);
86 static void iucv_sock_close(struct sock *sk);
87 static void iucv_sever_path(struct sock *, int);
88 
89 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
90 	struct packet_type *pt, struct net_device *orig_dev);
91 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
92 		   struct sk_buff *skb, u8 flags);
93 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
94 
95 /* Call Back functions */
96 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
97 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
98 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
99 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
100 				 u8 ipuser[16]);
101 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
102 static void iucv_callback_shutdown(struct iucv_path *, u8 ipuser[16]);
103 
104 static struct iucv_sock_list iucv_sk_list = {
105 	.lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
106 	.autobind_name = ATOMIC_INIT(0)
107 };
108 
109 static struct iucv_handler af_iucv_handler = {
110 	.path_pending	  = iucv_callback_connreq,
111 	.path_complete	  = iucv_callback_connack,
112 	.path_severed	  = iucv_callback_connrej,
113 	.message_pending  = iucv_callback_rx,
114 	.message_complete = iucv_callback_txdone,
115 	.path_quiesced	  = iucv_callback_shutdown,
116 };
117 
118 static inline void high_nmcpy(unsigned char *dst, char *src)
119 {
120        memcpy(dst, src, 8);
121 }
122 
123 static inline void low_nmcpy(unsigned char *dst, char *src)
124 {
125        memcpy(&dst[8], src, 8);
126 }
127 
128 static int afiucv_pm_prepare(struct device *dev)
129 {
130 #ifdef CONFIG_PM_DEBUG
131 	printk(KERN_WARNING "afiucv_pm_prepare\n");
132 #endif
133 	return 0;
134 }
135 
136 static void afiucv_pm_complete(struct device *dev)
137 {
138 #ifdef CONFIG_PM_DEBUG
139 	printk(KERN_WARNING "afiucv_pm_complete\n");
140 #endif
141 }
142 
143 /**
144  * afiucv_pm_freeze() - Freeze PM callback
145  * @dev:	AFIUCV dummy device
146  *
147  * Sever all established IUCV communication pathes
148  */
149 static int afiucv_pm_freeze(struct device *dev)
150 {
151 	struct iucv_sock *iucv;
152 	struct sock *sk;
153 	int err = 0;
154 
155 #ifdef CONFIG_PM_DEBUG
156 	printk(KERN_WARNING "afiucv_pm_freeze\n");
157 #endif
158 	read_lock(&iucv_sk_list.lock);
159 	sk_for_each(sk, &iucv_sk_list.head) {
160 		iucv = iucv_sk(sk);
161 		switch (sk->sk_state) {
162 		case IUCV_DISCONN:
163 		case IUCV_CLOSING:
164 		case IUCV_CONNECTED:
165 			iucv_sever_path(sk, 0);
166 			break;
167 		case IUCV_OPEN:
168 		case IUCV_BOUND:
169 		case IUCV_LISTEN:
170 		case IUCV_CLOSED:
171 		default:
172 			break;
173 		}
174 		skb_queue_purge(&iucv->send_skb_q);
175 		skb_queue_purge(&iucv->backlog_skb_q);
176 	}
177 	read_unlock(&iucv_sk_list.lock);
178 	return err;
179 }
180 
181 /**
182  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
183  * @dev:	AFIUCV dummy device
184  *
185  * socket clean up after freeze
186  */
187 static int afiucv_pm_restore_thaw(struct device *dev)
188 {
189 	struct sock *sk;
190 
191 #ifdef CONFIG_PM_DEBUG
192 	printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
193 #endif
194 	read_lock(&iucv_sk_list.lock);
195 	sk_for_each(sk, &iucv_sk_list.head) {
196 		switch (sk->sk_state) {
197 		case IUCV_CONNECTED:
198 			sk->sk_err = EPIPE;
199 			sk->sk_state = IUCV_DISCONN;
200 			sk->sk_state_change(sk);
201 			break;
202 		case IUCV_DISCONN:
203 		case IUCV_CLOSING:
204 		case IUCV_LISTEN:
205 		case IUCV_BOUND:
206 		case IUCV_OPEN:
207 		default:
208 			break;
209 		}
210 	}
211 	read_unlock(&iucv_sk_list.lock);
212 	return 0;
213 }
214 
215 static const struct dev_pm_ops afiucv_pm_ops = {
216 	.prepare = afiucv_pm_prepare,
217 	.complete = afiucv_pm_complete,
218 	.freeze = afiucv_pm_freeze,
219 	.thaw = afiucv_pm_restore_thaw,
220 	.restore = afiucv_pm_restore_thaw,
221 };
222 
223 static struct device_driver af_iucv_driver = {
224 	.owner = THIS_MODULE,
225 	.name = "afiucv",
226 	.bus  = NULL,
227 	.pm   = &afiucv_pm_ops,
228 };
229 
230 /* dummy device used as trigger for PM functions */
231 static struct device *af_iucv_dev;
232 
233 /**
234  * iucv_msg_length() - Returns the length of an iucv message.
235  * @msg:	Pointer to struct iucv_message, MUST NOT be NULL
236  *
237  * The function returns the length of the specified iucv message @msg of data
238  * stored in a buffer and of data stored in the parameter list (PRMDATA).
239  *
240  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
241  * data:
242  *	PRMDATA[0..6]	socket data (max 7 bytes);
243  *	PRMDATA[7]	socket data length value (len is 0xff - PRMDATA[7])
244  *
245  * The socket data length is computed by subtracting the socket data length
246  * value from 0xFF.
247  * If the socket data len is greater 7, then PRMDATA can be used for special
248  * notifications (see iucv_sock_shutdown); and further,
249  * if the socket data len is > 7, the function returns 8.
250  *
251  * Use this function to allocate socket buffers to store iucv message data.
252  */
253 static inline size_t iucv_msg_length(struct iucv_message *msg)
254 {
255 	size_t datalen;
256 
257 	if (msg->flags & IUCV_IPRMDATA) {
258 		datalen = 0xff - msg->rmmsg[7];
259 		return (datalen < 8) ? datalen : 8;
260 	}
261 	return msg->length;
262 }
263 
264 /**
265  * iucv_sock_in_state() - check for specific states
266  * @sk:		sock structure
267  * @state:	first iucv sk state
268  * @state:	second iucv sk state
269  *
270  * Returns true if the socket in either in the first or second state.
271  */
272 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
273 {
274 	return (sk->sk_state == state || sk->sk_state == state2);
275 }
276 
277 /**
278  * iucv_below_msglim() - function to check if messages can be sent
279  * @sk:		sock structure
280  *
281  * Returns true if the send queue length is lower than the message limit.
282  * Always returns true if the socket is not connected (no iucv path for
283  * checking the message limit).
284  */
285 static inline int iucv_below_msglim(struct sock *sk)
286 {
287 	struct iucv_sock *iucv = iucv_sk(sk);
288 
289 	if (sk->sk_state != IUCV_CONNECTED)
290 		return 1;
291 	if (iucv->transport == AF_IUCV_TRANS_IUCV)
292 		return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
293 	else
294 		return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
295 			(atomic_read(&iucv->pendings) <= 0));
296 }
297 
298 /**
299  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
300  */
301 static void iucv_sock_wake_msglim(struct sock *sk)
302 {
303 	struct socket_wq *wq;
304 
305 	rcu_read_lock();
306 	wq = rcu_dereference(sk->sk_wq);
307 	if (wq_has_sleeper(wq))
308 		wake_up_interruptible_all(&wq->wait);
309 	sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
310 	rcu_read_unlock();
311 }
312 
313 /**
314  * afiucv_hs_send() - send a message through HiperSockets transport
315  */
316 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
317 		   struct sk_buff *skb, u8 flags)
318 {
319 	struct iucv_sock *iucv = iucv_sk(sock);
320 	struct af_iucv_trans_hdr *phs_hdr;
321 	struct sk_buff *nskb;
322 	int err, confirm_recv = 0;
323 
324 	memset(skb->head, 0, ETH_HLEN);
325 	phs_hdr = (struct af_iucv_trans_hdr *)skb_push(skb,
326 					sizeof(struct af_iucv_trans_hdr));
327 	skb_reset_mac_header(skb);
328 	skb_reset_network_header(skb);
329 	skb_push(skb, ETH_HLEN);
330 	skb_reset_mac_header(skb);
331 	memset(phs_hdr, 0, sizeof(struct af_iucv_trans_hdr));
332 
333 	phs_hdr->magic = ETH_P_AF_IUCV;
334 	phs_hdr->version = 1;
335 	phs_hdr->flags = flags;
336 	if (flags == AF_IUCV_FLAG_SYN)
337 		phs_hdr->window = iucv->msglimit;
338 	else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
339 		confirm_recv = atomic_read(&iucv->msg_recv);
340 		phs_hdr->window = confirm_recv;
341 		if (confirm_recv)
342 			phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
343 	}
344 	memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
345 	memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
346 	memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
347 	memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
348 	ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
349 	ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
350 	ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
351 	ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
352 	if (imsg)
353 		memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
354 
355 	skb->dev = iucv->hs_dev;
356 	if (!skb->dev)
357 		return -ENODEV;
358 	if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev))
359 		return -ENETDOWN;
360 	if (skb->len > skb->dev->mtu) {
361 		if (sock->sk_type == SOCK_SEQPACKET)
362 			return -EMSGSIZE;
363 		else
364 			skb_trim(skb, skb->dev->mtu);
365 	}
366 	skb->protocol = ETH_P_AF_IUCV;
367 	nskb = skb_clone(skb, GFP_ATOMIC);
368 	if (!nskb)
369 		return -ENOMEM;
370 	skb_queue_tail(&iucv->send_skb_q, nskb);
371 	err = dev_queue_xmit(skb);
372 	if (net_xmit_eval(err)) {
373 		skb_unlink(nskb, &iucv->send_skb_q);
374 		kfree_skb(nskb);
375 	} else {
376 		atomic_sub(confirm_recv, &iucv->msg_recv);
377 		WARN_ON(atomic_read(&iucv->msg_recv) < 0);
378 	}
379 	return net_xmit_eval(err);
380 }
381 
382 static struct sock *__iucv_get_sock_by_name(char *nm)
383 {
384 	struct sock *sk;
385 
386 	sk_for_each(sk, &iucv_sk_list.head)
387 		if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
388 			return sk;
389 
390 	return NULL;
391 }
392 
393 static void iucv_sock_destruct(struct sock *sk)
394 {
395 	skb_queue_purge(&sk->sk_receive_queue);
396 	skb_queue_purge(&sk->sk_error_queue);
397 
398 	sk_mem_reclaim(sk);
399 
400 	if (!sock_flag(sk, SOCK_DEAD)) {
401 		pr_err("Attempt to release alive iucv socket %p\n", sk);
402 		return;
403 	}
404 
405 	WARN_ON(atomic_read(&sk->sk_rmem_alloc));
406 	WARN_ON(atomic_read(&sk->sk_wmem_alloc));
407 	WARN_ON(sk->sk_wmem_queued);
408 	WARN_ON(sk->sk_forward_alloc);
409 }
410 
411 /* Cleanup Listen */
412 static void iucv_sock_cleanup_listen(struct sock *parent)
413 {
414 	struct sock *sk;
415 
416 	/* Close non-accepted connections */
417 	while ((sk = iucv_accept_dequeue(parent, NULL))) {
418 		iucv_sock_close(sk);
419 		iucv_sock_kill(sk);
420 	}
421 
422 	parent->sk_state = IUCV_CLOSED;
423 }
424 
425 /* Kill socket (only if zapped and orphaned) */
426 static void iucv_sock_kill(struct sock *sk)
427 {
428 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
429 		return;
430 
431 	iucv_sock_unlink(&iucv_sk_list, sk);
432 	sock_set_flag(sk, SOCK_DEAD);
433 	sock_put(sk);
434 }
435 
436 /* Terminate an IUCV path */
437 static void iucv_sever_path(struct sock *sk, int with_user_data)
438 {
439 	unsigned char user_data[16];
440 	struct iucv_sock *iucv = iucv_sk(sk);
441 	struct iucv_path *path = iucv->path;
442 
443 	if (iucv->path) {
444 		iucv->path = NULL;
445 		if (with_user_data) {
446 			low_nmcpy(user_data, iucv->src_name);
447 			high_nmcpy(user_data, iucv->dst_name);
448 			ASCEBC(user_data, sizeof(user_data));
449 			pr_iucv->path_sever(path, user_data);
450 		} else
451 			pr_iucv->path_sever(path, NULL);
452 		iucv_path_free(path);
453 	}
454 }
455 
456 /* Send FIN through an IUCV socket for HIPER transport */
457 static int iucv_send_ctrl(struct sock *sk, u8 flags)
458 {
459 	int err = 0;
460 	int blen;
461 	struct sk_buff *skb;
462 
463 	blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
464 	skb = sock_alloc_send_skb(sk, blen, 1, &err);
465 	if (skb) {
466 		skb_reserve(skb, blen);
467 		err = afiucv_hs_send(NULL, sk, skb, flags);
468 	}
469 	return err;
470 }
471 
472 /* Close an IUCV socket */
473 static void iucv_sock_close(struct sock *sk)
474 {
475 	struct iucv_sock *iucv = iucv_sk(sk);
476 	unsigned long timeo;
477 	int err = 0;
478 
479 	lock_sock(sk);
480 
481 	switch (sk->sk_state) {
482 	case IUCV_LISTEN:
483 		iucv_sock_cleanup_listen(sk);
484 		break;
485 
486 	case IUCV_CONNECTED:
487 		if (iucv->transport == AF_IUCV_TRANS_HIPER) {
488 			err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
489 			sk->sk_state = IUCV_DISCONN;
490 			sk->sk_state_change(sk);
491 		}
492 	case IUCV_DISCONN:   /* fall through */
493 		sk->sk_state = IUCV_CLOSING;
494 		sk->sk_state_change(sk);
495 
496 		if (!err && !skb_queue_empty(&iucv->send_skb_q)) {
497 			if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
498 				timeo = sk->sk_lingertime;
499 			else
500 				timeo = IUCV_DISCONN_TIMEOUT;
501 			iucv_sock_wait(sk,
502 					iucv_sock_in_state(sk, IUCV_CLOSED, 0),
503 					timeo);
504 		}
505 
506 	case IUCV_CLOSING:   /* fall through */
507 		sk->sk_state = IUCV_CLOSED;
508 		sk->sk_state_change(sk);
509 
510 		sk->sk_err = ECONNRESET;
511 		sk->sk_state_change(sk);
512 
513 		skb_queue_purge(&iucv->send_skb_q);
514 		skb_queue_purge(&iucv->backlog_skb_q);
515 
516 	default:   /* fall through */
517 		iucv_sever_path(sk, 1);
518 	}
519 
520 	if (iucv->hs_dev) {
521 		dev_put(iucv->hs_dev);
522 		iucv->hs_dev = NULL;
523 		sk->sk_bound_dev_if = 0;
524 	}
525 
526 	/* mark socket for deletion by iucv_sock_kill() */
527 	sock_set_flag(sk, SOCK_ZAPPED);
528 
529 	release_sock(sk);
530 }
531 
532 static void iucv_sock_init(struct sock *sk, struct sock *parent)
533 {
534 	if (parent)
535 		sk->sk_type = parent->sk_type;
536 }
537 
538 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
539 {
540 	struct sock *sk;
541 	struct iucv_sock *iucv;
542 
543 	sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
544 	if (!sk)
545 		return NULL;
546 	iucv = iucv_sk(sk);
547 
548 	sock_init_data(sock, sk);
549 	INIT_LIST_HEAD(&iucv->accept_q);
550 	spin_lock_init(&iucv->accept_q_lock);
551 	skb_queue_head_init(&iucv->send_skb_q);
552 	INIT_LIST_HEAD(&iucv->message_q.list);
553 	spin_lock_init(&iucv->message_q.lock);
554 	skb_queue_head_init(&iucv->backlog_skb_q);
555 	iucv->send_tag = 0;
556 	atomic_set(&iucv->pendings, 0);
557 	iucv->flags = 0;
558 	iucv->msglimit = 0;
559 	atomic_set(&iucv->msg_sent, 0);
560 	atomic_set(&iucv->msg_recv, 0);
561 	iucv->path = NULL;
562 	iucv->sk_txnotify = afiucv_hs_callback_txnotify;
563 	memset(&iucv->src_user_id , 0, 32);
564 	if (pr_iucv)
565 		iucv->transport = AF_IUCV_TRANS_IUCV;
566 	else
567 		iucv->transport = AF_IUCV_TRANS_HIPER;
568 
569 	sk->sk_destruct = iucv_sock_destruct;
570 	sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
571 	sk->sk_allocation = GFP_DMA;
572 
573 	sock_reset_flag(sk, SOCK_ZAPPED);
574 
575 	sk->sk_protocol = proto;
576 	sk->sk_state	= IUCV_OPEN;
577 
578 	iucv_sock_link(&iucv_sk_list, sk);
579 	return sk;
580 }
581 
582 /* Create an IUCV socket */
583 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
584 			    int kern)
585 {
586 	struct sock *sk;
587 
588 	if (protocol && protocol != PF_IUCV)
589 		return -EPROTONOSUPPORT;
590 
591 	sock->state = SS_UNCONNECTED;
592 
593 	switch (sock->type) {
594 	case SOCK_STREAM:
595 		sock->ops = &iucv_sock_ops;
596 		break;
597 	case SOCK_SEQPACKET:
598 		/* currently, proto ops can handle both sk types */
599 		sock->ops = &iucv_sock_ops;
600 		break;
601 	default:
602 		return -ESOCKTNOSUPPORT;
603 	}
604 
605 	sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
606 	if (!sk)
607 		return -ENOMEM;
608 
609 	iucv_sock_init(sk, NULL);
610 
611 	return 0;
612 }
613 
614 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
615 {
616 	write_lock_bh(&l->lock);
617 	sk_add_node(sk, &l->head);
618 	write_unlock_bh(&l->lock);
619 }
620 
621 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
622 {
623 	write_lock_bh(&l->lock);
624 	sk_del_node_init(sk);
625 	write_unlock_bh(&l->lock);
626 }
627 
628 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
629 {
630 	unsigned long flags;
631 	struct iucv_sock *par = iucv_sk(parent);
632 
633 	sock_hold(sk);
634 	spin_lock_irqsave(&par->accept_q_lock, flags);
635 	list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
636 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
637 	iucv_sk(sk)->parent = parent;
638 	sk_acceptq_added(parent);
639 }
640 
641 void iucv_accept_unlink(struct sock *sk)
642 {
643 	unsigned long flags;
644 	struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
645 
646 	spin_lock_irqsave(&par->accept_q_lock, flags);
647 	list_del_init(&iucv_sk(sk)->accept_q);
648 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
649 	sk_acceptq_removed(iucv_sk(sk)->parent);
650 	iucv_sk(sk)->parent = NULL;
651 	sock_put(sk);
652 }
653 
654 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
655 {
656 	struct iucv_sock *isk, *n;
657 	struct sock *sk;
658 
659 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
660 		sk = (struct sock *) isk;
661 		lock_sock(sk);
662 
663 		if (sk->sk_state == IUCV_CLOSED) {
664 			iucv_accept_unlink(sk);
665 			release_sock(sk);
666 			continue;
667 		}
668 
669 		if (sk->sk_state == IUCV_CONNECTED ||
670 		    sk->sk_state == IUCV_DISCONN ||
671 		    !newsock) {
672 			iucv_accept_unlink(sk);
673 			if (newsock)
674 				sock_graft(sk, newsock);
675 
676 			release_sock(sk);
677 			return sk;
678 		}
679 
680 		release_sock(sk);
681 	}
682 	return NULL;
683 }
684 
685 /* Bind an unbound socket */
686 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
687 			  int addr_len)
688 {
689 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
690 	struct sock *sk = sock->sk;
691 	struct iucv_sock *iucv;
692 	int err = 0;
693 	struct net_device *dev;
694 	char uid[9];
695 
696 	/* Verify the input sockaddr */
697 	if (!addr || addr->sa_family != AF_IUCV)
698 		return -EINVAL;
699 
700 	lock_sock(sk);
701 	if (sk->sk_state != IUCV_OPEN) {
702 		err = -EBADFD;
703 		goto done;
704 	}
705 
706 	write_lock_bh(&iucv_sk_list.lock);
707 
708 	iucv = iucv_sk(sk);
709 	if (__iucv_get_sock_by_name(sa->siucv_name)) {
710 		err = -EADDRINUSE;
711 		goto done_unlock;
712 	}
713 	if (iucv->path)
714 		goto done_unlock;
715 
716 	/* Bind the socket */
717 	if (pr_iucv)
718 		if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
719 			goto vm_bind; /* VM IUCV transport */
720 
721 	/* try hiper transport */
722 	memcpy(uid, sa->siucv_user_id, sizeof(uid));
723 	ASCEBC(uid, 8);
724 	rcu_read_lock();
725 	for_each_netdev_rcu(&init_net, dev) {
726 		if (!memcmp(dev->perm_addr, uid, 8)) {
727 			memcpy(iucv->src_name, sa->siucv_name, 8);
728 			memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
729 			sk->sk_bound_dev_if = dev->ifindex;
730 			iucv->hs_dev = dev;
731 			dev_hold(dev);
732 			sk->sk_state = IUCV_BOUND;
733 			iucv->transport = AF_IUCV_TRANS_HIPER;
734 			if (!iucv->msglimit)
735 				iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
736 			rcu_read_unlock();
737 			goto done_unlock;
738 		}
739 	}
740 	rcu_read_unlock();
741 vm_bind:
742 	if (pr_iucv) {
743 		/* use local userid for backward compat */
744 		memcpy(iucv->src_name, sa->siucv_name, 8);
745 		memcpy(iucv->src_user_id, iucv_userid, 8);
746 		sk->sk_state = IUCV_BOUND;
747 		iucv->transport = AF_IUCV_TRANS_IUCV;
748 		if (!iucv->msglimit)
749 			iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
750 		goto done_unlock;
751 	}
752 	/* found no dev to bind */
753 	err = -ENODEV;
754 done_unlock:
755 	/* Release the socket list lock */
756 	write_unlock_bh(&iucv_sk_list.lock);
757 done:
758 	release_sock(sk);
759 	return err;
760 }
761 
762 /* Automatically bind an unbound socket */
763 static int iucv_sock_autobind(struct sock *sk)
764 {
765 	struct iucv_sock *iucv = iucv_sk(sk);
766 	char name[12];
767 	int err = 0;
768 
769 	if (unlikely(!pr_iucv))
770 		return -EPROTO;
771 
772 	memcpy(iucv->src_user_id, iucv_userid, 8);
773 
774 	write_lock_bh(&iucv_sk_list.lock);
775 
776 	sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
777 	while (__iucv_get_sock_by_name(name)) {
778 		sprintf(name, "%08x",
779 			atomic_inc_return(&iucv_sk_list.autobind_name));
780 	}
781 
782 	write_unlock_bh(&iucv_sk_list.lock);
783 
784 	memcpy(&iucv->src_name, name, 8);
785 
786 	if (!iucv->msglimit)
787 		iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
788 
789 	return err;
790 }
791 
792 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
793 {
794 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
795 	struct sock *sk = sock->sk;
796 	struct iucv_sock *iucv = iucv_sk(sk);
797 	unsigned char user_data[16];
798 	int err;
799 
800 	high_nmcpy(user_data, sa->siucv_name);
801 	low_nmcpy(user_data, iucv->src_name);
802 	ASCEBC(user_data, sizeof(user_data));
803 
804 	/* Create path. */
805 	iucv->path = iucv_path_alloc(iucv->msglimit,
806 				     IUCV_IPRMDATA, GFP_KERNEL);
807 	if (!iucv->path) {
808 		err = -ENOMEM;
809 		goto done;
810 	}
811 	err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
812 				    sa->siucv_user_id, NULL, user_data,
813 				    sk);
814 	if (err) {
815 		iucv_path_free(iucv->path);
816 		iucv->path = NULL;
817 		switch (err) {
818 		case 0x0b:	/* Target communicator is not logged on */
819 			err = -ENETUNREACH;
820 			break;
821 		case 0x0d:	/* Max connections for this guest exceeded */
822 		case 0x0e:	/* Max connections for target guest exceeded */
823 			err = -EAGAIN;
824 			break;
825 		case 0x0f:	/* Missing IUCV authorization */
826 			err = -EACCES;
827 			break;
828 		default:
829 			err = -ECONNREFUSED;
830 			break;
831 		}
832 	}
833 done:
834 	return err;
835 }
836 
837 /* Connect an unconnected socket */
838 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
839 			     int alen, int flags)
840 {
841 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
842 	struct sock *sk = sock->sk;
843 	struct iucv_sock *iucv = iucv_sk(sk);
844 	int err;
845 
846 	if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
847 		return -EINVAL;
848 
849 	if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
850 		return -EBADFD;
851 
852 	if (sk->sk_state == IUCV_OPEN &&
853 	    iucv->transport == AF_IUCV_TRANS_HIPER)
854 		return -EBADFD; /* explicit bind required */
855 
856 	if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
857 		return -EINVAL;
858 
859 	if (sk->sk_state == IUCV_OPEN) {
860 		err = iucv_sock_autobind(sk);
861 		if (unlikely(err))
862 			return err;
863 	}
864 
865 	lock_sock(sk);
866 
867 	/* Set the destination information */
868 	memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
869 	memcpy(iucv->dst_name, sa->siucv_name, 8);
870 
871 	if (iucv->transport == AF_IUCV_TRANS_HIPER)
872 		err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
873 	else
874 		err = afiucv_path_connect(sock, addr);
875 	if (err)
876 		goto done;
877 
878 	if (sk->sk_state != IUCV_CONNECTED)
879 		err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
880 							    IUCV_DISCONN),
881 				     sock_sndtimeo(sk, flags & O_NONBLOCK));
882 
883 	if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
884 		err = -ECONNREFUSED;
885 
886 	if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
887 		iucv_sever_path(sk, 0);
888 
889 done:
890 	release_sock(sk);
891 	return err;
892 }
893 
894 /* Move a socket into listening state. */
895 static int iucv_sock_listen(struct socket *sock, int backlog)
896 {
897 	struct sock *sk = sock->sk;
898 	int err;
899 
900 	lock_sock(sk);
901 
902 	err = -EINVAL;
903 	if (sk->sk_state != IUCV_BOUND)
904 		goto done;
905 
906 	if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
907 		goto done;
908 
909 	sk->sk_max_ack_backlog = backlog;
910 	sk->sk_ack_backlog = 0;
911 	sk->sk_state = IUCV_LISTEN;
912 	err = 0;
913 
914 done:
915 	release_sock(sk);
916 	return err;
917 }
918 
919 /* Accept a pending connection */
920 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
921 			    int flags)
922 {
923 	DECLARE_WAITQUEUE(wait, current);
924 	struct sock *sk = sock->sk, *nsk;
925 	long timeo;
926 	int err = 0;
927 
928 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
929 
930 	if (sk->sk_state != IUCV_LISTEN) {
931 		err = -EBADFD;
932 		goto done;
933 	}
934 
935 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
936 
937 	/* Wait for an incoming connection */
938 	add_wait_queue_exclusive(sk_sleep(sk), &wait);
939 	while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
940 		set_current_state(TASK_INTERRUPTIBLE);
941 		if (!timeo) {
942 			err = -EAGAIN;
943 			break;
944 		}
945 
946 		release_sock(sk);
947 		timeo = schedule_timeout(timeo);
948 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
949 
950 		if (sk->sk_state != IUCV_LISTEN) {
951 			err = -EBADFD;
952 			break;
953 		}
954 
955 		if (signal_pending(current)) {
956 			err = sock_intr_errno(timeo);
957 			break;
958 		}
959 	}
960 
961 	set_current_state(TASK_RUNNING);
962 	remove_wait_queue(sk_sleep(sk), &wait);
963 
964 	if (err)
965 		goto done;
966 
967 	newsock->state = SS_CONNECTED;
968 
969 done:
970 	release_sock(sk);
971 	return err;
972 }
973 
974 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
975 			     int *len, int peer)
976 {
977 	struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
978 	struct sock *sk = sock->sk;
979 	struct iucv_sock *iucv = iucv_sk(sk);
980 
981 	addr->sa_family = AF_IUCV;
982 	*len = sizeof(struct sockaddr_iucv);
983 
984 	if (peer) {
985 		memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
986 		memcpy(siucv->siucv_name, iucv->dst_name, 8);
987 	} else {
988 		memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
989 		memcpy(siucv->siucv_name, iucv->src_name, 8);
990 	}
991 	memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
992 	memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
993 	memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
994 
995 	return 0;
996 }
997 
998 /**
999  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1000  * @path:	IUCV path
1001  * @msg:	Pointer to a struct iucv_message
1002  * @skb:	The socket data to send, skb->len MUST BE <= 7
1003  *
1004  * Send the socket data in the parameter list in the iucv message
1005  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1006  * list and the socket data len at index 7 (last byte).
1007  * See also iucv_msg_length().
1008  *
1009  * Returns the error code from the iucv_message_send() call.
1010  */
1011 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1012 			  struct sk_buff *skb)
1013 {
1014 	u8 prmdata[8];
1015 
1016 	memcpy(prmdata, (void *) skb->data, skb->len);
1017 	prmdata[7] = 0xff - (u8) skb->len;
1018 	return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1019 				 (void *) prmdata, 8);
1020 }
1021 
1022 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
1023 			     struct msghdr *msg, size_t len)
1024 {
1025 	struct sock *sk = sock->sk;
1026 	struct iucv_sock *iucv = iucv_sk(sk);
1027 	struct sk_buff *skb;
1028 	struct iucv_message txmsg;
1029 	struct cmsghdr *cmsg;
1030 	int cmsg_done;
1031 	long timeo;
1032 	char user_id[9];
1033 	char appl_id[9];
1034 	int err;
1035 	int noblock = msg->msg_flags & MSG_DONTWAIT;
1036 
1037 	err = sock_error(sk);
1038 	if (err)
1039 		return err;
1040 
1041 	if (msg->msg_flags & MSG_OOB)
1042 		return -EOPNOTSUPP;
1043 
1044 	/* SOCK_SEQPACKET: we do not support segmented records */
1045 	if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1046 		return -EOPNOTSUPP;
1047 
1048 	lock_sock(sk);
1049 
1050 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
1051 		err = -EPIPE;
1052 		goto out;
1053 	}
1054 
1055 	/* Return if the socket is not in connected state */
1056 	if (sk->sk_state != IUCV_CONNECTED) {
1057 		err = -ENOTCONN;
1058 		goto out;
1059 	}
1060 
1061 	/* initialize defaults */
1062 	cmsg_done   = 0;	/* check for duplicate headers */
1063 	txmsg.class = 0;
1064 
1065 	/* iterate over control messages */
1066 	for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
1067 		cmsg = CMSG_NXTHDR(msg, cmsg)) {
1068 
1069 		if (!CMSG_OK(msg, cmsg)) {
1070 			err = -EINVAL;
1071 			goto out;
1072 		}
1073 
1074 		if (cmsg->cmsg_level != SOL_IUCV)
1075 			continue;
1076 
1077 		if (cmsg->cmsg_type & cmsg_done) {
1078 			err = -EINVAL;
1079 			goto out;
1080 		}
1081 		cmsg_done |= cmsg->cmsg_type;
1082 
1083 		switch (cmsg->cmsg_type) {
1084 		case SCM_IUCV_TRGCLS:
1085 			if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1086 				err = -EINVAL;
1087 				goto out;
1088 			}
1089 
1090 			/* set iucv message target class */
1091 			memcpy(&txmsg.class,
1092 				(void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1093 
1094 			break;
1095 
1096 		default:
1097 			err = -EINVAL;
1098 			goto out;
1099 			break;
1100 		}
1101 	}
1102 
1103 	/* allocate one skb for each iucv message:
1104 	 * this is fine for SOCK_SEQPACKET (unless we want to support
1105 	 * segmented records using the MSG_EOR flag), but
1106 	 * for SOCK_STREAM we might want to improve it in future */
1107 	if (iucv->transport == AF_IUCV_TRANS_HIPER)
1108 		skb = sock_alloc_send_skb(sk,
1109 			len + sizeof(struct af_iucv_trans_hdr) + ETH_HLEN,
1110 			noblock, &err);
1111 	else
1112 		skb = sock_alloc_send_skb(sk, len, noblock, &err);
1113 	if (!skb) {
1114 		err = -ENOMEM;
1115 		goto out;
1116 	}
1117 	if (iucv->transport == AF_IUCV_TRANS_HIPER)
1118 		skb_reserve(skb, sizeof(struct af_iucv_trans_hdr) + ETH_HLEN);
1119 	if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
1120 		err = -EFAULT;
1121 		goto fail;
1122 	}
1123 
1124 	/* wait if outstanding messages for iucv path has reached */
1125 	timeo = sock_sndtimeo(sk, noblock);
1126 	err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1127 	if (err)
1128 		goto fail;
1129 
1130 	/* return -ECONNRESET if the socket is no longer connected */
1131 	if (sk->sk_state != IUCV_CONNECTED) {
1132 		err = -ECONNRESET;
1133 		goto fail;
1134 	}
1135 
1136 	/* increment and save iucv message tag for msg_completion cbk */
1137 	txmsg.tag = iucv->send_tag++;
1138 	IUCV_SKB_CB(skb)->tag = txmsg.tag;
1139 
1140 	if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1141 		atomic_inc(&iucv->msg_sent);
1142 		err = afiucv_hs_send(&txmsg, sk, skb, 0);
1143 		if (err) {
1144 			atomic_dec(&iucv->msg_sent);
1145 			goto fail;
1146 		}
1147 		goto release;
1148 	}
1149 	skb_queue_tail(&iucv->send_skb_q, skb);
1150 
1151 	if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
1152 	      && skb->len <= 7) {
1153 		err = iucv_send_iprm(iucv->path, &txmsg, skb);
1154 
1155 		/* on success: there is no message_complete callback
1156 		 * for an IPRMDATA msg; remove skb from send queue */
1157 		if (err == 0) {
1158 			skb_unlink(skb, &iucv->send_skb_q);
1159 			kfree_skb(skb);
1160 		}
1161 
1162 		/* this error should never happen since the
1163 		 * IUCV_IPRMDATA path flag is set... sever path */
1164 		if (err == 0x15) {
1165 			pr_iucv->path_sever(iucv->path, NULL);
1166 			skb_unlink(skb, &iucv->send_skb_q);
1167 			err = -EPIPE;
1168 			goto fail;
1169 		}
1170 	} else
1171 		err = pr_iucv->message_send(iucv->path, &txmsg, 0, 0,
1172 					(void *) skb->data, skb->len);
1173 	if (err) {
1174 		if (err == 3) {
1175 			user_id[8] = 0;
1176 			memcpy(user_id, iucv->dst_user_id, 8);
1177 			appl_id[8] = 0;
1178 			memcpy(appl_id, iucv->dst_name, 8);
1179 			pr_err("Application %s on z/VM guest %s"
1180 				" exceeds message limit\n",
1181 				appl_id, user_id);
1182 			err = -EAGAIN;
1183 		} else
1184 			err = -EPIPE;
1185 		skb_unlink(skb, &iucv->send_skb_q);
1186 		goto fail;
1187 	}
1188 
1189 release:
1190 	release_sock(sk);
1191 	return len;
1192 
1193 fail:
1194 	kfree_skb(skb);
1195 out:
1196 	release_sock(sk);
1197 	return err;
1198 }
1199 
1200 /* iucv_fragment_skb() - Fragment a single IUCV message into multiple skb's
1201  *
1202  * Locking: must be called with message_q.lock held
1203  */
1204 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
1205 {
1206 	int dataleft, size, copied = 0;
1207 	struct sk_buff *nskb;
1208 
1209 	dataleft = len;
1210 	while (dataleft) {
1211 		if (dataleft >= sk->sk_rcvbuf / 4)
1212 			size = sk->sk_rcvbuf / 4;
1213 		else
1214 			size = dataleft;
1215 
1216 		nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
1217 		if (!nskb)
1218 			return -ENOMEM;
1219 
1220 		/* copy target class to control buffer of new skb */
1221 		IUCV_SKB_CB(nskb)->class = IUCV_SKB_CB(skb)->class;
1222 
1223 		/* copy data fragment */
1224 		memcpy(nskb->data, skb->data + copied, size);
1225 		copied += size;
1226 		dataleft -= size;
1227 
1228 		skb_reset_transport_header(nskb);
1229 		skb_reset_network_header(nskb);
1230 		nskb->len = size;
1231 
1232 		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
1233 	}
1234 
1235 	return 0;
1236 }
1237 
1238 /* iucv_process_message() - Receive a single outstanding IUCV message
1239  *
1240  * Locking: must be called with message_q.lock held
1241  */
1242 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1243 				 struct iucv_path *path,
1244 				 struct iucv_message *msg)
1245 {
1246 	int rc;
1247 	unsigned int len;
1248 
1249 	len = iucv_msg_length(msg);
1250 
1251 	/* store msg target class in the second 4 bytes of skb ctrl buffer */
1252 	/* Note: the first 4 bytes are reserved for msg tag */
1253 	IUCV_SKB_CB(skb)->class = msg->class;
1254 
1255 	/* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1256 	if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1257 		if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1258 			skb->data = NULL;
1259 			skb->len = 0;
1260 		}
1261 	} else {
1262 		rc = pr_iucv->message_receive(path, msg,
1263 					      msg->flags & IUCV_IPRMDATA,
1264 					      skb->data, len, NULL);
1265 		if (rc) {
1266 			kfree_skb(skb);
1267 			return;
1268 		}
1269 		/* we need to fragment iucv messages for SOCK_STREAM only;
1270 		 * for SOCK_SEQPACKET, it is only relevant if we support
1271 		 * record segmentation using MSG_EOR (see also recvmsg()) */
1272 		if (sk->sk_type == SOCK_STREAM &&
1273 		    skb->truesize >= sk->sk_rcvbuf / 4) {
1274 			rc = iucv_fragment_skb(sk, skb, len);
1275 			kfree_skb(skb);
1276 			skb = NULL;
1277 			if (rc) {
1278 				pr_iucv->path_sever(path, NULL);
1279 				return;
1280 			}
1281 			skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
1282 		} else {
1283 			skb_reset_transport_header(skb);
1284 			skb_reset_network_header(skb);
1285 			skb->len = len;
1286 		}
1287 	}
1288 
1289 	IUCV_SKB_CB(skb)->offset = 0;
1290 	if (sock_queue_rcv_skb(sk, skb))
1291 		skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1292 }
1293 
1294 /* iucv_process_message_q() - Process outstanding IUCV messages
1295  *
1296  * Locking: must be called with message_q.lock held
1297  */
1298 static void iucv_process_message_q(struct sock *sk)
1299 {
1300 	struct iucv_sock *iucv = iucv_sk(sk);
1301 	struct sk_buff *skb;
1302 	struct sock_msg_q *p, *n;
1303 
1304 	list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1305 		skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1306 		if (!skb)
1307 			break;
1308 		iucv_process_message(sk, skb, p->path, &p->msg);
1309 		list_del(&p->list);
1310 		kfree(p);
1311 		if (!skb_queue_empty(&iucv->backlog_skb_q))
1312 			break;
1313 	}
1314 }
1315 
1316 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1317 			     struct msghdr *msg, size_t len, int flags)
1318 {
1319 	int noblock = flags & MSG_DONTWAIT;
1320 	struct sock *sk = sock->sk;
1321 	struct iucv_sock *iucv = iucv_sk(sk);
1322 	unsigned int copied, rlen;
1323 	struct sk_buff *skb, *rskb, *cskb;
1324 	int err = 0;
1325 	u32 offset;
1326 
1327 	if ((sk->sk_state == IUCV_DISCONN) &&
1328 	    skb_queue_empty(&iucv->backlog_skb_q) &&
1329 	    skb_queue_empty(&sk->sk_receive_queue) &&
1330 	    list_empty(&iucv->message_q.list))
1331 		return 0;
1332 
1333 	if (flags & (MSG_OOB))
1334 		return -EOPNOTSUPP;
1335 
1336 	/* receive/dequeue next skb:
1337 	 * the function understands MSG_PEEK and, thus, does not dequeue skb */
1338 	skb = skb_recv_datagram(sk, flags, noblock, &err);
1339 	if (!skb) {
1340 		if (sk->sk_shutdown & RCV_SHUTDOWN)
1341 			return 0;
1342 		return err;
1343 	}
1344 
1345 	offset = IUCV_SKB_CB(skb)->offset;
1346 	rlen   = skb->len - offset;		/* real length of skb */
1347 	copied = min_t(unsigned int, rlen, len);
1348 	if (!rlen)
1349 		sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1350 
1351 	cskb = skb;
1352 	if (skb_copy_datagram_iovec(cskb, offset, msg->msg_iov, copied)) {
1353 		if (!(flags & MSG_PEEK))
1354 			skb_queue_head(&sk->sk_receive_queue, skb);
1355 		return -EFAULT;
1356 	}
1357 
1358 	/* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1359 	if (sk->sk_type == SOCK_SEQPACKET) {
1360 		if (copied < rlen)
1361 			msg->msg_flags |= MSG_TRUNC;
1362 		/* each iucv message contains a complete record */
1363 		msg->msg_flags |= MSG_EOR;
1364 	}
1365 
1366 	/* create control message to store iucv msg target class:
1367 	 * get the trgcls from the control buffer of the skb due to
1368 	 * fragmentation of original iucv message. */
1369 	err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1370 		       sizeof(IUCV_SKB_CB(skb)->class),
1371 		       (void *)&IUCV_SKB_CB(skb)->class);
1372 	if (err) {
1373 		if (!(flags & MSG_PEEK))
1374 			skb_queue_head(&sk->sk_receive_queue, skb);
1375 		return err;
1376 	}
1377 
1378 	/* Mark read part of skb as used */
1379 	if (!(flags & MSG_PEEK)) {
1380 
1381 		/* SOCK_STREAM: re-queue skb if it contains unreceived data */
1382 		if (sk->sk_type == SOCK_STREAM) {
1383 			if (copied < rlen) {
1384 				IUCV_SKB_CB(skb)->offset = offset + copied;
1385 				skb_queue_head(&sk->sk_receive_queue, skb);
1386 				goto done;
1387 			}
1388 		}
1389 
1390 		kfree_skb(skb);
1391 		if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1392 			atomic_inc(&iucv->msg_recv);
1393 			if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1394 				WARN_ON(1);
1395 				iucv_sock_close(sk);
1396 				return -EFAULT;
1397 			}
1398 		}
1399 
1400 		/* Queue backlog skbs */
1401 		spin_lock_bh(&iucv->message_q.lock);
1402 		rskb = skb_dequeue(&iucv->backlog_skb_q);
1403 		while (rskb) {
1404 			IUCV_SKB_CB(rskb)->offset = 0;
1405 			if (sock_queue_rcv_skb(sk, rskb)) {
1406 				skb_queue_head(&iucv->backlog_skb_q,
1407 						rskb);
1408 				break;
1409 			} else {
1410 				rskb = skb_dequeue(&iucv->backlog_skb_q);
1411 			}
1412 		}
1413 		if (skb_queue_empty(&iucv->backlog_skb_q)) {
1414 			if (!list_empty(&iucv->message_q.list))
1415 				iucv_process_message_q(sk);
1416 			if (atomic_read(&iucv->msg_recv) >=
1417 							iucv->msglimit / 2) {
1418 				err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1419 				if (err) {
1420 					sk->sk_state = IUCV_DISCONN;
1421 					sk->sk_state_change(sk);
1422 				}
1423 			}
1424 		}
1425 		spin_unlock_bh(&iucv->message_q.lock);
1426 	}
1427 
1428 done:
1429 	/* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1430 	if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1431 		copied = rlen;
1432 
1433 	return copied;
1434 }
1435 
1436 static inline unsigned int iucv_accept_poll(struct sock *parent)
1437 {
1438 	struct iucv_sock *isk, *n;
1439 	struct sock *sk;
1440 
1441 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1442 		sk = (struct sock *) isk;
1443 
1444 		if (sk->sk_state == IUCV_CONNECTED)
1445 			return POLLIN | POLLRDNORM;
1446 	}
1447 
1448 	return 0;
1449 }
1450 
1451 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1452 			    poll_table *wait)
1453 {
1454 	struct sock *sk = sock->sk;
1455 	unsigned int mask = 0;
1456 
1457 	sock_poll_wait(file, sk_sleep(sk), wait);
1458 
1459 	if (sk->sk_state == IUCV_LISTEN)
1460 		return iucv_accept_poll(sk);
1461 
1462 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1463 		mask |= POLLERR |
1464 			(sock_flag(sk, SOCK_SELECT_ERR_QUEUE) ? POLLPRI : 0);
1465 
1466 	if (sk->sk_shutdown & RCV_SHUTDOWN)
1467 		mask |= POLLRDHUP;
1468 
1469 	if (sk->sk_shutdown == SHUTDOWN_MASK)
1470 		mask |= POLLHUP;
1471 
1472 	if (!skb_queue_empty(&sk->sk_receive_queue) ||
1473 	    (sk->sk_shutdown & RCV_SHUTDOWN))
1474 		mask |= POLLIN | POLLRDNORM;
1475 
1476 	if (sk->sk_state == IUCV_CLOSED)
1477 		mask |= POLLHUP;
1478 
1479 	if (sk->sk_state == IUCV_DISCONN)
1480 		mask |= POLLIN;
1481 
1482 	if (sock_writeable(sk) && iucv_below_msglim(sk))
1483 		mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1484 	else
1485 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1486 
1487 	return mask;
1488 }
1489 
1490 static int iucv_sock_shutdown(struct socket *sock, int how)
1491 {
1492 	struct sock *sk = sock->sk;
1493 	struct iucv_sock *iucv = iucv_sk(sk);
1494 	struct iucv_message txmsg;
1495 	int err = 0;
1496 
1497 	how++;
1498 
1499 	if ((how & ~SHUTDOWN_MASK) || !how)
1500 		return -EINVAL;
1501 
1502 	lock_sock(sk);
1503 	switch (sk->sk_state) {
1504 	case IUCV_LISTEN:
1505 	case IUCV_DISCONN:
1506 	case IUCV_CLOSING:
1507 	case IUCV_CLOSED:
1508 		err = -ENOTCONN;
1509 		goto fail;
1510 	default:
1511 		break;
1512 	}
1513 
1514 	if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1515 		if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1516 			txmsg.class = 0;
1517 			txmsg.tag = 0;
1518 			err = pr_iucv->message_send(iucv->path, &txmsg,
1519 				IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1520 			if (err) {
1521 				switch (err) {
1522 				case 1:
1523 					err = -ENOTCONN;
1524 					break;
1525 				case 2:
1526 					err = -ECONNRESET;
1527 					break;
1528 				default:
1529 					err = -ENOTCONN;
1530 					break;
1531 				}
1532 			}
1533 		} else
1534 			iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1535 	}
1536 
1537 	sk->sk_shutdown |= how;
1538 	if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1539 		if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1540 			err = pr_iucv->path_quiesce(iucv->path, NULL);
1541 			if (err)
1542 				err = -ENOTCONN;
1543 /*			skb_queue_purge(&sk->sk_receive_queue); */
1544 		}
1545 		skb_queue_purge(&sk->sk_receive_queue);
1546 	}
1547 
1548 	/* Wake up anyone sleeping in poll */
1549 	sk->sk_state_change(sk);
1550 
1551 fail:
1552 	release_sock(sk);
1553 	return err;
1554 }
1555 
1556 static int iucv_sock_release(struct socket *sock)
1557 {
1558 	struct sock *sk = sock->sk;
1559 	int err = 0;
1560 
1561 	if (!sk)
1562 		return 0;
1563 
1564 	iucv_sock_close(sk);
1565 
1566 	sock_orphan(sk);
1567 	iucv_sock_kill(sk);
1568 	return err;
1569 }
1570 
1571 /* getsockopt and setsockopt */
1572 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1573 				char __user *optval, unsigned int optlen)
1574 {
1575 	struct sock *sk = sock->sk;
1576 	struct iucv_sock *iucv = iucv_sk(sk);
1577 	int val;
1578 	int rc;
1579 
1580 	if (level != SOL_IUCV)
1581 		return -ENOPROTOOPT;
1582 
1583 	if (optlen < sizeof(int))
1584 		return -EINVAL;
1585 
1586 	if (get_user(val, (int __user *) optval))
1587 		return -EFAULT;
1588 
1589 	rc = 0;
1590 
1591 	lock_sock(sk);
1592 	switch (optname) {
1593 	case SO_IPRMDATA_MSG:
1594 		if (val)
1595 			iucv->flags |= IUCV_IPRMDATA;
1596 		else
1597 			iucv->flags &= ~IUCV_IPRMDATA;
1598 		break;
1599 	case SO_MSGLIMIT:
1600 		switch (sk->sk_state) {
1601 		case IUCV_OPEN:
1602 		case IUCV_BOUND:
1603 			if (val < 1 || val > (u16)(~0))
1604 				rc = -EINVAL;
1605 			else
1606 				iucv->msglimit = val;
1607 			break;
1608 		default:
1609 			rc = -EINVAL;
1610 			break;
1611 		}
1612 		break;
1613 	default:
1614 		rc = -ENOPROTOOPT;
1615 		break;
1616 	}
1617 	release_sock(sk);
1618 
1619 	return rc;
1620 }
1621 
1622 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1623 				char __user *optval, int __user *optlen)
1624 {
1625 	struct sock *sk = sock->sk;
1626 	struct iucv_sock *iucv = iucv_sk(sk);
1627 	unsigned int val;
1628 	int len;
1629 
1630 	if (level != SOL_IUCV)
1631 		return -ENOPROTOOPT;
1632 
1633 	if (get_user(len, optlen))
1634 		return -EFAULT;
1635 
1636 	if (len < 0)
1637 		return -EINVAL;
1638 
1639 	len = min_t(unsigned int, len, sizeof(int));
1640 
1641 	switch (optname) {
1642 	case SO_IPRMDATA_MSG:
1643 		val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1644 		break;
1645 	case SO_MSGLIMIT:
1646 		lock_sock(sk);
1647 		val = (iucv->path != NULL) ? iucv->path->msglim	/* connected */
1648 					   : iucv->msglimit;	/* default */
1649 		release_sock(sk);
1650 		break;
1651 	case SO_MSGSIZE:
1652 		if (sk->sk_state == IUCV_OPEN)
1653 			return -EBADFD;
1654 		val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1655 				sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1656 				0x7fffffff;
1657 		break;
1658 	default:
1659 		return -ENOPROTOOPT;
1660 	}
1661 
1662 	if (put_user(len, optlen))
1663 		return -EFAULT;
1664 	if (copy_to_user(optval, &val, len))
1665 		return -EFAULT;
1666 
1667 	return 0;
1668 }
1669 
1670 
1671 /* Callback wrappers - called from iucv base support */
1672 static int iucv_callback_connreq(struct iucv_path *path,
1673 				 u8 ipvmid[8], u8 ipuser[16])
1674 {
1675 	unsigned char user_data[16];
1676 	unsigned char nuser_data[16];
1677 	unsigned char src_name[8];
1678 	struct sock *sk, *nsk;
1679 	struct iucv_sock *iucv, *niucv;
1680 	int err;
1681 
1682 	memcpy(src_name, ipuser, 8);
1683 	EBCASC(src_name, 8);
1684 	/* Find out if this path belongs to af_iucv. */
1685 	read_lock(&iucv_sk_list.lock);
1686 	iucv = NULL;
1687 	sk = NULL;
1688 	sk_for_each(sk, &iucv_sk_list.head)
1689 		if (sk->sk_state == IUCV_LISTEN &&
1690 		    !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1691 			/*
1692 			 * Found a listening socket with
1693 			 * src_name == ipuser[0-7].
1694 			 */
1695 			iucv = iucv_sk(sk);
1696 			break;
1697 		}
1698 	read_unlock(&iucv_sk_list.lock);
1699 	if (!iucv)
1700 		/* No socket found, not one of our paths. */
1701 		return -EINVAL;
1702 
1703 	bh_lock_sock(sk);
1704 
1705 	/* Check if parent socket is listening */
1706 	low_nmcpy(user_data, iucv->src_name);
1707 	high_nmcpy(user_data, iucv->dst_name);
1708 	ASCEBC(user_data, sizeof(user_data));
1709 	if (sk->sk_state != IUCV_LISTEN) {
1710 		err = pr_iucv->path_sever(path, user_data);
1711 		iucv_path_free(path);
1712 		goto fail;
1713 	}
1714 
1715 	/* Check for backlog size */
1716 	if (sk_acceptq_is_full(sk)) {
1717 		err = pr_iucv->path_sever(path, user_data);
1718 		iucv_path_free(path);
1719 		goto fail;
1720 	}
1721 
1722 	/* Create the new socket */
1723 	nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1724 	if (!nsk) {
1725 		err = pr_iucv->path_sever(path, user_data);
1726 		iucv_path_free(path);
1727 		goto fail;
1728 	}
1729 
1730 	niucv = iucv_sk(nsk);
1731 	iucv_sock_init(nsk, sk);
1732 
1733 	/* Set the new iucv_sock */
1734 	memcpy(niucv->dst_name, ipuser + 8, 8);
1735 	EBCASC(niucv->dst_name, 8);
1736 	memcpy(niucv->dst_user_id, ipvmid, 8);
1737 	memcpy(niucv->src_name, iucv->src_name, 8);
1738 	memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1739 	niucv->path = path;
1740 
1741 	/* Call iucv_accept */
1742 	high_nmcpy(nuser_data, ipuser + 8);
1743 	memcpy(nuser_data + 8, niucv->src_name, 8);
1744 	ASCEBC(nuser_data + 8, 8);
1745 
1746 	/* set message limit for path based on msglimit of accepting socket */
1747 	niucv->msglimit = iucv->msglimit;
1748 	path->msglim = iucv->msglimit;
1749 	err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1750 	if (err) {
1751 		iucv_sever_path(nsk, 1);
1752 		iucv_sock_kill(nsk);
1753 		goto fail;
1754 	}
1755 
1756 	iucv_accept_enqueue(sk, nsk);
1757 
1758 	/* Wake up accept */
1759 	nsk->sk_state = IUCV_CONNECTED;
1760 	sk->sk_data_ready(sk);
1761 	err = 0;
1762 fail:
1763 	bh_unlock_sock(sk);
1764 	return 0;
1765 }
1766 
1767 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1768 {
1769 	struct sock *sk = path->private;
1770 
1771 	sk->sk_state = IUCV_CONNECTED;
1772 	sk->sk_state_change(sk);
1773 }
1774 
1775 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1776 {
1777 	struct sock *sk = path->private;
1778 	struct iucv_sock *iucv = iucv_sk(sk);
1779 	struct sk_buff *skb;
1780 	struct sock_msg_q *save_msg;
1781 	int len;
1782 
1783 	if (sk->sk_shutdown & RCV_SHUTDOWN) {
1784 		pr_iucv->message_reject(path, msg);
1785 		return;
1786 	}
1787 
1788 	spin_lock(&iucv->message_q.lock);
1789 
1790 	if (!list_empty(&iucv->message_q.list) ||
1791 	    !skb_queue_empty(&iucv->backlog_skb_q))
1792 		goto save_message;
1793 
1794 	len = atomic_read(&sk->sk_rmem_alloc);
1795 	len += SKB_TRUESIZE(iucv_msg_length(msg));
1796 	if (len > sk->sk_rcvbuf)
1797 		goto save_message;
1798 
1799 	skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1800 	if (!skb)
1801 		goto save_message;
1802 
1803 	iucv_process_message(sk, skb, path, msg);
1804 	goto out_unlock;
1805 
1806 save_message:
1807 	save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1808 	if (!save_msg)
1809 		goto out_unlock;
1810 	save_msg->path = path;
1811 	save_msg->msg = *msg;
1812 
1813 	list_add_tail(&save_msg->list, &iucv->message_q.list);
1814 
1815 out_unlock:
1816 	spin_unlock(&iucv->message_q.lock);
1817 }
1818 
1819 static void iucv_callback_txdone(struct iucv_path *path,
1820 				 struct iucv_message *msg)
1821 {
1822 	struct sock *sk = path->private;
1823 	struct sk_buff *this = NULL;
1824 	struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1825 	struct sk_buff *list_skb = list->next;
1826 	unsigned long flags;
1827 
1828 	bh_lock_sock(sk);
1829 	if (!skb_queue_empty(list)) {
1830 		spin_lock_irqsave(&list->lock, flags);
1831 
1832 		while (list_skb != (struct sk_buff *)list) {
1833 			if (msg->tag != IUCV_SKB_CB(list_skb)->tag) {
1834 				this = list_skb;
1835 				break;
1836 			}
1837 			list_skb = list_skb->next;
1838 		}
1839 		if (this)
1840 			__skb_unlink(this, list);
1841 
1842 		spin_unlock_irqrestore(&list->lock, flags);
1843 
1844 		if (this) {
1845 			kfree_skb(this);
1846 			/* wake up any process waiting for sending */
1847 			iucv_sock_wake_msglim(sk);
1848 		}
1849 	}
1850 
1851 	if (sk->sk_state == IUCV_CLOSING) {
1852 		if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1853 			sk->sk_state = IUCV_CLOSED;
1854 			sk->sk_state_change(sk);
1855 		}
1856 	}
1857 	bh_unlock_sock(sk);
1858 
1859 }
1860 
1861 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1862 {
1863 	struct sock *sk = path->private;
1864 
1865 	if (sk->sk_state == IUCV_CLOSED)
1866 		return;
1867 
1868 	bh_lock_sock(sk);
1869 	iucv_sever_path(sk, 1);
1870 	sk->sk_state = IUCV_DISCONN;
1871 
1872 	sk->sk_state_change(sk);
1873 	bh_unlock_sock(sk);
1874 }
1875 
1876 /* called if the other communication side shuts down its RECV direction;
1877  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1878  */
1879 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1880 {
1881 	struct sock *sk = path->private;
1882 
1883 	bh_lock_sock(sk);
1884 	if (sk->sk_state != IUCV_CLOSED) {
1885 		sk->sk_shutdown |= SEND_SHUTDOWN;
1886 		sk->sk_state_change(sk);
1887 	}
1888 	bh_unlock_sock(sk);
1889 }
1890 
1891 /***************** HiperSockets transport callbacks ********************/
1892 static void afiucv_swap_src_dest(struct sk_buff *skb)
1893 {
1894 	struct af_iucv_trans_hdr *trans_hdr =
1895 				(struct af_iucv_trans_hdr *)skb->data;
1896 	char tmpID[8];
1897 	char tmpName[8];
1898 
1899 	ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1900 	ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1901 	ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1902 	ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1903 	memcpy(tmpID, trans_hdr->srcUserID, 8);
1904 	memcpy(tmpName, trans_hdr->srcAppName, 8);
1905 	memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1906 	memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1907 	memcpy(trans_hdr->destUserID, tmpID, 8);
1908 	memcpy(trans_hdr->destAppName, tmpName, 8);
1909 	skb_push(skb, ETH_HLEN);
1910 	memset(skb->data, 0, ETH_HLEN);
1911 }
1912 
1913 /**
1914  * afiucv_hs_callback_syn - react on received SYN
1915  **/
1916 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1917 {
1918 	struct sock *nsk;
1919 	struct iucv_sock *iucv, *niucv;
1920 	struct af_iucv_trans_hdr *trans_hdr;
1921 	int err;
1922 
1923 	iucv = iucv_sk(sk);
1924 	trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
1925 	if (!iucv) {
1926 		/* no sock - connection refused */
1927 		afiucv_swap_src_dest(skb);
1928 		trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1929 		err = dev_queue_xmit(skb);
1930 		goto out;
1931 	}
1932 
1933 	nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1934 	bh_lock_sock(sk);
1935 	if ((sk->sk_state != IUCV_LISTEN) ||
1936 	    sk_acceptq_is_full(sk) ||
1937 	    !nsk) {
1938 		/* error on server socket - connection refused */
1939 		if (nsk)
1940 			sk_free(nsk);
1941 		afiucv_swap_src_dest(skb);
1942 		trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1943 		err = dev_queue_xmit(skb);
1944 		bh_unlock_sock(sk);
1945 		goto out;
1946 	}
1947 
1948 	niucv = iucv_sk(nsk);
1949 	iucv_sock_init(nsk, sk);
1950 	niucv->transport = AF_IUCV_TRANS_HIPER;
1951 	niucv->msglimit = iucv->msglimit;
1952 	if (!trans_hdr->window)
1953 		niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1954 	else
1955 		niucv->msglimit_peer = trans_hdr->window;
1956 	memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
1957 	memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
1958 	memcpy(niucv->src_name, iucv->src_name, 8);
1959 	memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1960 	nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
1961 	niucv->hs_dev = iucv->hs_dev;
1962 	dev_hold(niucv->hs_dev);
1963 	afiucv_swap_src_dest(skb);
1964 	trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
1965 	trans_hdr->window = niucv->msglimit;
1966 	/* if receiver acks the xmit connection is established */
1967 	err = dev_queue_xmit(skb);
1968 	if (!err) {
1969 		iucv_accept_enqueue(sk, nsk);
1970 		nsk->sk_state = IUCV_CONNECTED;
1971 		sk->sk_data_ready(sk);
1972 	} else
1973 		iucv_sock_kill(nsk);
1974 	bh_unlock_sock(sk);
1975 
1976 out:
1977 	return NET_RX_SUCCESS;
1978 }
1979 
1980 /**
1981  * afiucv_hs_callback_synack() - react on received SYN-ACK
1982  **/
1983 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
1984 {
1985 	struct iucv_sock *iucv = iucv_sk(sk);
1986 	struct af_iucv_trans_hdr *trans_hdr =
1987 					(struct af_iucv_trans_hdr *)skb->data;
1988 
1989 	if (!iucv)
1990 		goto out;
1991 	if (sk->sk_state != IUCV_BOUND)
1992 		goto out;
1993 	bh_lock_sock(sk);
1994 	iucv->msglimit_peer = trans_hdr->window;
1995 	sk->sk_state = IUCV_CONNECTED;
1996 	sk->sk_state_change(sk);
1997 	bh_unlock_sock(sk);
1998 out:
1999 	kfree_skb(skb);
2000 	return NET_RX_SUCCESS;
2001 }
2002 
2003 /**
2004  * afiucv_hs_callback_synfin() - react on received SYN_FIN
2005  **/
2006 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2007 {
2008 	struct iucv_sock *iucv = iucv_sk(sk);
2009 
2010 	if (!iucv)
2011 		goto out;
2012 	if (sk->sk_state != IUCV_BOUND)
2013 		goto out;
2014 	bh_lock_sock(sk);
2015 	sk->sk_state = IUCV_DISCONN;
2016 	sk->sk_state_change(sk);
2017 	bh_unlock_sock(sk);
2018 out:
2019 	kfree_skb(skb);
2020 	return NET_RX_SUCCESS;
2021 }
2022 
2023 /**
2024  * afiucv_hs_callback_fin() - react on received FIN
2025  **/
2026 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2027 {
2028 	struct iucv_sock *iucv = iucv_sk(sk);
2029 
2030 	/* other end of connection closed */
2031 	if (!iucv)
2032 		goto out;
2033 	bh_lock_sock(sk);
2034 	if (sk->sk_state == IUCV_CONNECTED) {
2035 		sk->sk_state = IUCV_DISCONN;
2036 		sk->sk_state_change(sk);
2037 	}
2038 	bh_unlock_sock(sk);
2039 out:
2040 	kfree_skb(skb);
2041 	return NET_RX_SUCCESS;
2042 }
2043 
2044 /**
2045  * afiucv_hs_callback_win() - react on received WIN
2046  **/
2047 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2048 {
2049 	struct iucv_sock *iucv = iucv_sk(sk);
2050 	struct af_iucv_trans_hdr *trans_hdr =
2051 					(struct af_iucv_trans_hdr *)skb->data;
2052 
2053 	if (!iucv)
2054 		return NET_RX_SUCCESS;
2055 
2056 	if (sk->sk_state != IUCV_CONNECTED)
2057 		return NET_RX_SUCCESS;
2058 
2059 	atomic_sub(trans_hdr->window, &iucv->msg_sent);
2060 	iucv_sock_wake_msglim(sk);
2061 	return NET_RX_SUCCESS;
2062 }
2063 
2064 /**
2065  * afiucv_hs_callback_rx() - react on received data
2066  **/
2067 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2068 {
2069 	struct iucv_sock *iucv = iucv_sk(sk);
2070 
2071 	if (!iucv) {
2072 		kfree_skb(skb);
2073 		return NET_RX_SUCCESS;
2074 	}
2075 
2076 	if (sk->sk_state != IUCV_CONNECTED) {
2077 		kfree_skb(skb);
2078 		return NET_RX_SUCCESS;
2079 	}
2080 
2081 	if (sk->sk_shutdown & RCV_SHUTDOWN) {
2082 		kfree_skb(skb);
2083 		return NET_RX_SUCCESS;
2084 	}
2085 
2086 		/* write stuff from iucv_msg to skb cb */
2087 	if (skb->len < sizeof(struct af_iucv_trans_hdr)) {
2088 		kfree_skb(skb);
2089 		return NET_RX_SUCCESS;
2090 	}
2091 	skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2092 	skb_reset_transport_header(skb);
2093 	skb_reset_network_header(skb);
2094 	IUCV_SKB_CB(skb)->offset = 0;
2095 	spin_lock(&iucv->message_q.lock);
2096 	if (skb_queue_empty(&iucv->backlog_skb_q)) {
2097 		if (sock_queue_rcv_skb(sk, skb)) {
2098 			/* handle rcv queue full */
2099 			skb_queue_tail(&iucv->backlog_skb_q, skb);
2100 		}
2101 	} else
2102 		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2103 	spin_unlock(&iucv->message_q.lock);
2104 	return NET_RX_SUCCESS;
2105 }
2106 
2107 /**
2108  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2109  *                   transport
2110  *                   called from netif RX softirq
2111  **/
2112 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2113 	struct packet_type *pt, struct net_device *orig_dev)
2114 {
2115 	struct sock *sk;
2116 	struct iucv_sock *iucv;
2117 	struct af_iucv_trans_hdr *trans_hdr;
2118 	char nullstring[8];
2119 	int err = 0;
2120 
2121 	skb_pull(skb, ETH_HLEN);
2122 	trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
2123 	EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2124 	EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2125 	EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2126 	EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2127 	memset(nullstring, 0, sizeof(nullstring));
2128 	iucv = NULL;
2129 	sk = NULL;
2130 	read_lock(&iucv_sk_list.lock);
2131 	sk_for_each(sk, &iucv_sk_list.head) {
2132 		if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2133 			if ((!memcmp(&iucv_sk(sk)->src_name,
2134 				     trans_hdr->destAppName, 8)) &&
2135 			    (!memcmp(&iucv_sk(sk)->src_user_id,
2136 				     trans_hdr->destUserID, 8)) &&
2137 			    (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2138 			    (!memcmp(&iucv_sk(sk)->dst_user_id,
2139 				     nullstring, 8))) {
2140 				iucv = iucv_sk(sk);
2141 				break;
2142 			}
2143 		} else {
2144 			if ((!memcmp(&iucv_sk(sk)->src_name,
2145 				     trans_hdr->destAppName, 8)) &&
2146 			    (!memcmp(&iucv_sk(sk)->src_user_id,
2147 				     trans_hdr->destUserID, 8)) &&
2148 			    (!memcmp(&iucv_sk(sk)->dst_name,
2149 				     trans_hdr->srcAppName, 8)) &&
2150 			    (!memcmp(&iucv_sk(sk)->dst_user_id,
2151 				     trans_hdr->srcUserID, 8))) {
2152 				iucv = iucv_sk(sk);
2153 				break;
2154 			}
2155 		}
2156 	}
2157 	read_unlock(&iucv_sk_list.lock);
2158 	if (!iucv)
2159 		sk = NULL;
2160 
2161 	/* no sock
2162 	how should we send with no sock
2163 	1) send without sock no send rc checking?
2164 	2) introduce default sock to handle this cases
2165 
2166 	 SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2167 	 data -> send FIN
2168 	 SYN|ACK, SYN|FIN, FIN -> no action? */
2169 
2170 	switch (trans_hdr->flags) {
2171 	case AF_IUCV_FLAG_SYN:
2172 		/* connect request */
2173 		err = afiucv_hs_callback_syn(sk, skb);
2174 		break;
2175 	case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2176 		/* connect request confirmed */
2177 		err = afiucv_hs_callback_synack(sk, skb);
2178 		break;
2179 	case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2180 		/* connect request refused */
2181 		err = afiucv_hs_callback_synfin(sk, skb);
2182 		break;
2183 	case (AF_IUCV_FLAG_FIN):
2184 		/* close request */
2185 		err = afiucv_hs_callback_fin(sk, skb);
2186 		break;
2187 	case (AF_IUCV_FLAG_WIN):
2188 		err = afiucv_hs_callback_win(sk, skb);
2189 		if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2190 			kfree_skb(skb);
2191 			break;
2192 		}
2193 		/* fall through and receive non-zero length data */
2194 	case (AF_IUCV_FLAG_SHT):
2195 		/* shutdown request */
2196 		/* fall through and receive zero length data */
2197 	case 0:
2198 		/* plain data frame */
2199 		IUCV_SKB_CB(skb)->class = trans_hdr->iucv_hdr.class;
2200 		err = afiucv_hs_callback_rx(sk, skb);
2201 		break;
2202 	default:
2203 		;
2204 	}
2205 
2206 	return err;
2207 }
2208 
2209 /**
2210  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2211  *                                 transport
2212  **/
2213 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2214 					enum iucv_tx_notify n)
2215 {
2216 	struct sock *isk = skb->sk;
2217 	struct sock *sk = NULL;
2218 	struct iucv_sock *iucv = NULL;
2219 	struct sk_buff_head *list;
2220 	struct sk_buff *list_skb;
2221 	struct sk_buff *nskb;
2222 	unsigned long flags;
2223 
2224 	read_lock_irqsave(&iucv_sk_list.lock, flags);
2225 	sk_for_each(sk, &iucv_sk_list.head)
2226 		if (sk == isk) {
2227 			iucv = iucv_sk(sk);
2228 			break;
2229 		}
2230 	read_unlock_irqrestore(&iucv_sk_list.lock, flags);
2231 
2232 	if (!iucv || sock_flag(sk, SOCK_ZAPPED))
2233 		return;
2234 
2235 	list = &iucv->send_skb_q;
2236 	spin_lock_irqsave(&list->lock, flags);
2237 	if (skb_queue_empty(list))
2238 		goto out_unlock;
2239 	list_skb = list->next;
2240 	nskb = list_skb->next;
2241 	while (list_skb != (struct sk_buff *)list) {
2242 		if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2243 			switch (n) {
2244 			case TX_NOTIFY_OK:
2245 				__skb_unlink(list_skb, list);
2246 				kfree_skb(list_skb);
2247 				iucv_sock_wake_msglim(sk);
2248 				break;
2249 			case TX_NOTIFY_PENDING:
2250 				atomic_inc(&iucv->pendings);
2251 				break;
2252 			case TX_NOTIFY_DELAYED_OK:
2253 				__skb_unlink(list_skb, list);
2254 				atomic_dec(&iucv->pendings);
2255 				if (atomic_read(&iucv->pendings) <= 0)
2256 					iucv_sock_wake_msglim(sk);
2257 				kfree_skb(list_skb);
2258 				break;
2259 			case TX_NOTIFY_UNREACHABLE:
2260 			case TX_NOTIFY_DELAYED_UNREACHABLE:
2261 			case TX_NOTIFY_TPQFULL: /* not yet used */
2262 			case TX_NOTIFY_GENERALERROR:
2263 			case TX_NOTIFY_DELAYED_GENERALERROR:
2264 				__skb_unlink(list_skb, list);
2265 				kfree_skb(list_skb);
2266 				if (sk->sk_state == IUCV_CONNECTED) {
2267 					sk->sk_state = IUCV_DISCONN;
2268 					sk->sk_state_change(sk);
2269 				}
2270 				break;
2271 			}
2272 			break;
2273 		}
2274 		list_skb = nskb;
2275 		nskb = nskb->next;
2276 	}
2277 out_unlock:
2278 	spin_unlock_irqrestore(&list->lock, flags);
2279 
2280 	if (sk->sk_state == IUCV_CLOSING) {
2281 		if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
2282 			sk->sk_state = IUCV_CLOSED;
2283 			sk->sk_state_change(sk);
2284 		}
2285 	}
2286 
2287 }
2288 
2289 /*
2290  * afiucv_netdev_event: handle netdev notifier chain events
2291  */
2292 static int afiucv_netdev_event(struct notifier_block *this,
2293 			       unsigned long event, void *ptr)
2294 {
2295 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
2296 	struct sock *sk;
2297 	struct iucv_sock *iucv;
2298 
2299 	switch (event) {
2300 	case NETDEV_REBOOT:
2301 	case NETDEV_GOING_DOWN:
2302 		sk_for_each(sk, &iucv_sk_list.head) {
2303 			iucv = iucv_sk(sk);
2304 			if ((iucv->hs_dev == event_dev) &&
2305 			    (sk->sk_state == IUCV_CONNECTED)) {
2306 				if (event == NETDEV_GOING_DOWN)
2307 					iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2308 				sk->sk_state = IUCV_DISCONN;
2309 				sk->sk_state_change(sk);
2310 			}
2311 		}
2312 		break;
2313 	case NETDEV_DOWN:
2314 	case NETDEV_UNREGISTER:
2315 	default:
2316 		break;
2317 	}
2318 	return NOTIFY_DONE;
2319 }
2320 
2321 static struct notifier_block afiucv_netdev_notifier = {
2322 	.notifier_call = afiucv_netdev_event,
2323 };
2324 
2325 static const struct proto_ops iucv_sock_ops = {
2326 	.family		= PF_IUCV,
2327 	.owner		= THIS_MODULE,
2328 	.release	= iucv_sock_release,
2329 	.bind		= iucv_sock_bind,
2330 	.connect	= iucv_sock_connect,
2331 	.listen		= iucv_sock_listen,
2332 	.accept		= iucv_sock_accept,
2333 	.getname	= iucv_sock_getname,
2334 	.sendmsg	= iucv_sock_sendmsg,
2335 	.recvmsg	= iucv_sock_recvmsg,
2336 	.poll		= iucv_sock_poll,
2337 	.ioctl		= sock_no_ioctl,
2338 	.mmap		= sock_no_mmap,
2339 	.socketpair	= sock_no_socketpair,
2340 	.shutdown	= iucv_sock_shutdown,
2341 	.setsockopt	= iucv_sock_setsockopt,
2342 	.getsockopt	= iucv_sock_getsockopt,
2343 };
2344 
2345 static const struct net_proto_family iucv_sock_family_ops = {
2346 	.family	= AF_IUCV,
2347 	.owner	= THIS_MODULE,
2348 	.create	= iucv_sock_create,
2349 };
2350 
2351 static struct packet_type iucv_packet_type = {
2352 	.type = cpu_to_be16(ETH_P_AF_IUCV),
2353 	.func = afiucv_hs_rcv,
2354 };
2355 
2356 static int afiucv_iucv_init(void)
2357 {
2358 	int err;
2359 
2360 	err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2361 	if (err)
2362 		goto out;
2363 	/* establish dummy device */
2364 	af_iucv_driver.bus = pr_iucv->bus;
2365 	err = driver_register(&af_iucv_driver);
2366 	if (err)
2367 		goto out_iucv;
2368 	af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2369 	if (!af_iucv_dev) {
2370 		err = -ENOMEM;
2371 		goto out_driver;
2372 	}
2373 	dev_set_name(af_iucv_dev, "af_iucv");
2374 	af_iucv_dev->bus = pr_iucv->bus;
2375 	af_iucv_dev->parent = pr_iucv->root;
2376 	af_iucv_dev->release = (void (*)(struct device *))kfree;
2377 	af_iucv_dev->driver = &af_iucv_driver;
2378 	err = device_register(af_iucv_dev);
2379 	if (err)
2380 		goto out_driver;
2381 	return 0;
2382 
2383 out_driver:
2384 	driver_unregister(&af_iucv_driver);
2385 out_iucv:
2386 	pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2387 out:
2388 	return err;
2389 }
2390 
2391 static int __init afiucv_init(void)
2392 {
2393 	int err;
2394 
2395 	if (MACHINE_IS_VM) {
2396 		cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2397 		if (unlikely(err)) {
2398 			WARN_ON(err);
2399 			err = -EPROTONOSUPPORT;
2400 			goto out;
2401 		}
2402 
2403 		pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2404 		if (!pr_iucv) {
2405 			printk(KERN_WARNING "iucv_if lookup failed\n");
2406 			memset(&iucv_userid, 0, sizeof(iucv_userid));
2407 		}
2408 	} else {
2409 		memset(&iucv_userid, 0, sizeof(iucv_userid));
2410 		pr_iucv = NULL;
2411 	}
2412 
2413 	err = proto_register(&iucv_proto, 0);
2414 	if (err)
2415 		goto out;
2416 	err = sock_register(&iucv_sock_family_ops);
2417 	if (err)
2418 		goto out_proto;
2419 
2420 	if (pr_iucv) {
2421 		err = afiucv_iucv_init();
2422 		if (err)
2423 			goto out_sock;
2424 	} else
2425 		register_netdevice_notifier(&afiucv_netdev_notifier);
2426 	dev_add_pack(&iucv_packet_type);
2427 	return 0;
2428 
2429 out_sock:
2430 	sock_unregister(PF_IUCV);
2431 out_proto:
2432 	proto_unregister(&iucv_proto);
2433 out:
2434 	if (pr_iucv)
2435 		symbol_put(iucv_if);
2436 	return err;
2437 }
2438 
2439 static void __exit afiucv_exit(void)
2440 {
2441 	if (pr_iucv) {
2442 		device_unregister(af_iucv_dev);
2443 		driver_unregister(&af_iucv_driver);
2444 		pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2445 		symbol_put(iucv_if);
2446 	} else
2447 		unregister_netdevice_notifier(&afiucv_netdev_notifier);
2448 	dev_remove_pack(&iucv_packet_type);
2449 	sock_unregister(PF_IUCV);
2450 	proto_unregister(&iucv_proto);
2451 }
2452 
2453 module_init(afiucv_init);
2454 module_exit(afiucv_exit);
2455 
2456 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2457 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2458 MODULE_VERSION(VERSION);
2459 MODULE_LICENSE("GPL");
2460 MODULE_ALIAS_NETPROTO(PF_IUCV);
2461 
2462