xref: /openbmc/linux/net/iucv/af_iucv.c (revision 9d56dd3b083a3bec56e9da35ce07baca81030b03)
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/iucv.h>
31 #include <net/iucv/af_iucv.h>
32 
33 #define VERSION "1.1"
34 
35 static char iucv_userid[80];
36 
37 static const struct proto_ops iucv_sock_ops;
38 
39 static struct proto iucv_proto = {
40 	.name		= "AF_IUCV",
41 	.owner		= THIS_MODULE,
42 	.obj_size	= sizeof(struct iucv_sock),
43 };
44 
45 /* special AF_IUCV IPRM messages */
46 static const u8 iprm_shutdown[8] =
47 	{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
48 
49 #define TRGCLS_SIZE	(sizeof(((struct iucv_message *)0)->class))
50 
51 /* macros to set/get socket control buffer at correct offset */
52 #define CB_TAG(skb)	((skb)->cb)		/* iucv message tag */
53 #define CB_TAG_LEN	(sizeof(((struct iucv_message *) 0)->tag))
54 #define CB_TRGCLS(skb)	((skb)->cb + CB_TAG_LEN) /* iucv msg target class */
55 #define CB_TRGCLS_LEN	(TRGCLS_SIZE)
56 
57 #define __iucv_sock_wait(sk, condition, timeo, ret)			\
58 do {									\
59 	DEFINE_WAIT(__wait);						\
60 	long __timeo = timeo;						\
61 	ret = 0;							\
62 	prepare_to_wait(sk->sk_sleep, &__wait, TASK_INTERRUPTIBLE);	\
63 	while (!(condition)) {						\
64 		if (!__timeo) {						\
65 			ret = -EAGAIN;					\
66 			break;						\
67 		}							\
68 		if (signal_pending(current)) {				\
69 			ret = sock_intr_errno(__timeo);			\
70 			break;						\
71 		}							\
72 		release_sock(sk);					\
73 		__timeo = schedule_timeout(__timeo);			\
74 		lock_sock(sk);						\
75 		ret = sock_error(sk);					\
76 		if (ret)						\
77 			break;						\
78 	}								\
79 	finish_wait(sk->sk_sleep, &__wait);				\
80 } while (0)
81 
82 #define iucv_sock_wait(sk, condition, timeo)				\
83 ({									\
84 	int __ret = 0;							\
85 	if (!(condition))						\
86 		__iucv_sock_wait(sk, condition, timeo, __ret);		\
87 	__ret;								\
88 })
89 
90 static void iucv_sock_kill(struct sock *sk);
91 static void iucv_sock_close(struct sock *sk);
92 
93 /* Call Back functions */
94 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
95 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
96 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
97 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
98 				 u8 ipuser[16]);
99 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
100 static void iucv_callback_shutdown(struct iucv_path *, u8 ipuser[16]);
101 
102 static struct iucv_sock_list iucv_sk_list = {
103 	.lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
104 	.autobind_name = ATOMIC_INIT(0)
105 };
106 
107 static struct iucv_handler af_iucv_handler = {
108 	.path_pending	  = iucv_callback_connreq,
109 	.path_complete	  = iucv_callback_connack,
110 	.path_severed	  = iucv_callback_connrej,
111 	.message_pending  = iucv_callback_rx,
112 	.message_complete = iucv_callback_txdone,
113 	.path_quiesced	  = iucv_callback_shutdown,
114 };
115 
116 static inline void high_nmcpy(unsigned char *dst, char *src)
117 {
118        memcpy(dst, src, 8);
119 }
120 
121 static inline void low_nmcpy(unsigned char *dst, char *src)
122 {
123        memcpy(&dst[8], src, 8);
124 }
125 
126 static int afiucv_pm_prepare(struct device *dev)
127 {
128 #ifdef CONFIG_PM_DEBUG
129 	printk(KERN_WARNING "afiucv_pm_prepare\n");
130 #endif
131 	return 0;
132 }
133 
134 static void afiucv_pm_complete(struct device *dev)
135 {
136 #ifdef CONFIG_PM_DEBUG
137 	printk(KERN_WARNING "afiucv_pm_complete\n");
138 #endif
139 	return;
140 }
141 
142 /**
143  * afiucv_pm_freeze() - Freeze PM callback
144  * @dev:	AFIUCV dummy device
145  *
146  * Sever all established IUCV communication pathes
147  */
148 static int afiucv_pm_freeze(struct device *dev)
149 {
150 	struct iucv_sock *iucv;
151 	struct sock *sk;
152 	struct hlist_node *node;
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, node, &iucv_sk_list.head) {
160 		iucv = iucv_sk(sk);
161 		skb_queue_purge(&iucv->send_skb_q);
162 		skb_queue_purge(&iucv->backlog_skb_q);
163 		switch (sk->sk_state) {
164 		case IUCV_SEVERED:
165 		case IUCV_DISCONN:
166 		case IUCV_CLOSING:
167 		case IUCV_CONNECTED:
168 			if (iucv->path) {
169 				err = iucv_path_sever(iucv->path, NULL);
170 				iucv_path_free(iucv->path);
171 				iucv->path = NULL;
172 			}
173 			break;
174 		case IUCV_OPEN:
175 		case IUCV_BOUND:
176 		case IUCV_LISTEN:
177 		case IUCV_CLOSED:
178 		default:
179 			break;
180 		}
181 	}
182 	read_unlock(&iucv_sk_list.lock);
183 	return err;
184 }
185 
186 /**
187  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
188  * @dev:	AFIUCV dummy device
189  *
190  * socket clean up after freeze
191  */
192 static int afiucv_pm_restore_thaw(struct device *dev)
193 {
194 	struct iucv_sock *iucv;
195 	struct sock *sk;
196 	struct hlist_node *node;
197 
198 #ifdef CONFIG_PM_DEBUG
199 	printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
200 #endif
201 	read_lock(&iucv_sk_list.lock);
202 	sk_for_each(sk, node, &iucv_sk_list.head) {
203 		iucv = iucv_sk(sk);
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_SEVERED:
212 		case IUCV_CLOSING:
213 		case IUCV_LISTEN:
214 		case IUCV_BOUND:
215 		case IUCV_OPEN:
216 		default:
217 			break;
218 		}
219 	}
220 	read_unlock(&iucv_sk_list.lock);
221 	return 0;
222 }
223 
224 static const struct dev_pm_ops afiucv_pm_ops = {
225 	.prepare = afiucv_pm_prepare,
226 	.complete = afiucv_pm_complete,
227 	.freeze = afiucv_pm_freeze,
228 	.thaw = afiucv_pm_restore_thaw,
229 	.restore = afiucv_pm_restore_thaw,
230 };
231 
232 static struct device_driver af_iucv_driver = {
233 	.owner = THIS_MODULE,
234 	.name = "afiucv",
235 	.bus  = &iucv_bus,
236 	.pm   = &afiucv_pm_ops,
237 };
238 
239 /* dummy device used as trigger for PM functions */
240 static struct device *af_iucv_dev;
241 
242 /**
243  * iucv_msg_length() - Returns the length of an iucv message.
244  * @msg:	Pointer to struct iucv_message, MUST NOT be NULL
245  *
246  * The function returns the length of the specified iucv message @msg of data
247  * stored in a buffer and of data stored in the parameter list (PRMDATA).
248  *
249  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
250  * data:
251  *	PRMDATA[0..6]	socket data (max 7 bytes);
252  *	PRMDATA[7]	socket data length value (len is 0xff - PRMDATA[7])
253  *
254  * The socket data length is computed by substracting the socket data length
255  * value from 0xFF.
256  * If the socket data len is greater 7, then PRMDATA can be used for special
257  * notifications (see iucv_sock_shutdown); and further,
258  * if the socket data len is > 7, the function returns 8.
259  *
260  * Use this function to allocate socket buffers to store iucv message data.
261  */
262 static inline size_t iucv_msg_length(struct iucv_message *msg)
263 {
264 	size_t datalen;
265 
266 	if (msg->flags & IUCV_IPRMDATA) {
267 		datalen = 0xff - msg->rmmsg[7];
268 		return (datalen < 8) ? datalen : 8;
269 	}
270 	return msg->length;
271 }
272 
273 /**
274  * iucv_sock_in_state() - check for specific states
275  * @sk:		sock structure
276  * @state:	first iucv sk state
277  * @state:	second iucv sk state
278  *
279  * Returns true if the socket in either in the first or second state.
280  */
281 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
282 {
283 	return (sk->sk_state == state || sk->sk_state == state2);
284 }
285 
286 /**
287  * iucv_below_msglim() - function to check if messages can be sent
288  * @sk:		sock structure
289  *
290  * Returns true if the send queue length is lower than the message limit.
291  * Always returns true if the socket is not connected (no iucv path for
292  * checking the message limit).
293  */
294 static inline int iucv_below_msglim(struct sock *sk)
295 {
296 	struct iucv_sock *iucv = iucv_sk(sk);
297 
298 	if (sk->sk_state != IUCV_CONNECTED)
299 		return 1;
300 	return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
301 }
302 
303 /**
304  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
305  */
306 static void iucv_sock_wake_msglim(struct sock *sk)
307 {
308 	read_lock(&sk->sk_callback_lock);
309 	if (sk_has_sleeper(sk))
310 		wake_up_interruptible_all(sk->sk_sleep);
311 	sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
312 	read_unlock(&sk->sk_callback_lock);
313 }
314 
315 /* Timers */
316 static void iucv_sock_timeout(unsigned long arg)
317 {
318 	struct sock *sk = (struct sock *)arg;
319 
320 	bh_lock_sock(sk);
321 	sk->sk_err = ETIMEDOUT;
322 	sk->sk_state_change(sk);
323 	bh_unlock_sock(sk);
324 
325 	iucv_sock_kill(sk);
326 	sock_put(sk);
327 }
328 
329 static void iucv_sock_clear_timer(struct sock *sk)
330 {
331 	sk_stop_timer(sk, &sk->sk_timer);
332 }
333 
334 static struct sock *__iucv_get_sock_by_name(char *nm)
335 {
336 	struct sock *sk;
337 	struct hlist_node *node;
338 
339 	sk_for_each(sk, node, &iucv_sk_list.head)
340 		if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
341 			return sk;
342 
343 	return NULL;
344 }
345 
346 static void iucv_sock_destruct(struct sock *sk)
347 {
348 	skb_queue_purge(&sk->sk_receive_queue);
349 	skb_queue_purge(&sk->sk_write_queue);
350 }
351 
352 /* Cleanup Listen */
353 static void iucv_sock_cleanup_listen(struct sock *parent)
354 {
355 	struct sock *sk;
356 
357 	/* Close non-accepted connections */
358 	while ((sk = iucv_accept_dequeue(parent, NULL))) {
359 		iucv_sock_close(sk);
360 		iucv_sock_kill(sk);
361 	}
362 
363 	parent->sk_state = IUCV_CLOSED;
364 }
365 
366 /* Kill socket (only if zapped and orphaned) */
367 static void iucv_sock_kill(struct sock *sk)
368 {
369 	if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
370 		return;
371 
372 	iucv_sock_unlink(&iucv_sk_list, sk);
373 	sock_set_flag(sk, SOCK_DEAD);
374 	sock_put(sk);
375 }
376 
377 /* Close an IUCV socket */
378 static void iucv_sock_close(struct sock *sk)
379 {
380 	unsigned char user_data[16];
381 	struct iucv_sock *iucv = iucv_sk(sk);
382 	int err;
383 	unsigned long timeo;
384 
385 	iucv_sock_clear_timer(sk);
386 	lock_sock(sk);
387 
388 	switch (sk->sk_state) {
389 	case IUCV_LISTEN:
390 		iucv_sock_cleanup_listen(sk);
391 		break;
392 
393 	case IUCV_CONNECTED:
394 	case IUCV_DISCONN:
395 		err = 0;
396 
397 		sk->sk_state = IUCV_CLOSING;
398 		sk->sk_state_change(sk);
399 
400 		if (!skb_queue_empty(&iucv->send_skb_q)) {
401 			if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
402 				timeo = sk->sk_lingertime;
403 			else
404 				timeo = IUCV_DISCONN_TIMEOUT;
405 			err = iucv_sock_wait(sk,
406 					iucv_sock_in_state(sk, IUCV_CLOSED, 0),
407 					timeo);
408 		}
409 
410 	case IUCV_CLOSING:   /* fall through */
411 		sk->sk_state = IUCV_CLOSED;
412 		sk->sk_state_change(sk);
413 
414 		if (iucv->path) {
415 			low_nmcpy(user_data, iucv->src_name);
416 			high_nmcpy(user_data, iucv->dst_name);
417 			ASCEBC(user_data, sizeof(user_data));
418 			err = iucv_path_sever(iucv->path, user_data);
419 			iucv_path_free(iucv->path);
420 			iucv->path = NULL;
421 		}
422 
423 		sk->sk_err = ECONNRESET;
424 		sk->sk_state_change(sk);
425 
426 		skb_queue_purge(&iucv->send_skb_q);
427 		skb_queue_purge(&iucv->backlog_skb_q);
428 		break;
429 
430 	default:
431 		/* nothing to do here */
432 		break;
433 	}
434 
435 	/* mark socket for deletion by iucv_sock_kill() */
436 	sock_set_flag(sk, SOCK_ZAPPED);
437 
438 	release_sock(sk);
439 }
440 
441 static void iucv_sock_init(struct sock *sk, struct sock *parent)
442 {
443 	if (parent)
444 		sk->sk_type = parent->sk_type;
445 }
446 
447 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
448 {
449 	struct sock *sk;
450 
451 	sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
452 	if (!sk)
453 		return NULL;
454 
455 	sock_init_data(sock, sk);
456 	INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
457 	spin_lock_init(&iucv_sk(sk)->accept_q_lock);
458 	skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
459 	INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
460 	spin_lock_init(&iucv_sk(sk)->message_q.lock);
461 	skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
462 	iucv_sk(sk)->send_tag = 0;
463 	iucv_sk(sk)->flags = 0;
464 	iucv_sk(sk)->msglimit = IUCV_QUEUELEN_DEFAULT;
465 	iucv_sk(sk)->path = NULL;
466 	memset(&iucv_sk(sk)->src_user_id , 0, 32);
467 
468 	sk->sk_destruct = iucv_sock_destruct;
469 	sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
470 	sk->sk_allocation = GFP_DMA;
471 
472 	sock_reset_flag(sk, SOCK_ZAPPED);
473 
474 	sk->sk_protocol = proto;
475 	sk->sk_state	= IUCV_OPEN;
476 
477 	setup_timer(&sk->sk_timer, iucv_sock_timeout, (unsigned long)sk);
478 
479 	iucv_sock_link(&iucv_sk_list, sk);
480 	return sk;
481 }
482 
483 /* Create an IUCV socket */
484 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
485 			    int kern)
486 {
487 	struct sock *sk;
488 
489 	if (protocol && protocol != PF_IUCV)
490 		return -EPROTONOSUPPORT;
491 
492 	sock->state = SS_UNCONNECTED;
493 
494 	switch (sock->type) {
495 	case SOCK_STREAM:
496 		sock->ops = &iucv_sock_ops;
497 		break;
498 	case SOCK_SEQPACKET:
499 		/* currently, proto ops can handle both sk types */
500 		sock->ops = &iucv_sock_ops;
501 		break;
502 	default:
503 		return -ESOCKTNOSUPPORT;
504 	}
505 
506 	sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
507 	if (!sk)
508 		return -ENOMEM;
509 
510 	iucv_sock_init(sk, NULL);
511 
512 	return 0;
513 }
514 
515 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
516 {
517 	write_lock_bh(&l->lock);
518 	sk_add_node(sk, &l->head);
519 	write_unlock_bh(&l->lock);
520 }
521 
522 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
523 {
524 	write_lock_bh(&l->lock);
525 	sk_del_node_init(sk);
526 	write_unlock_bh(&l->lock);
527 }
528 
529 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
530 {
531 	unsigned long flags;
532 	struct iucv_sock *par = iucv_sk(parent);
533 
534 	sock_hold(sk);
535 	spin_lock_irqsave(&par->accept_q_lock, flags);
536 	list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
537 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
538 	iucv_sk(sk)->parent = parent;
539 	sk_acceptq_added(parent);
540 }
541 
542 void iucv_accept_unlink(struct sock *sk)
543 {
544 	unsigned long flags;
545 	struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
546 
547 	spin_lock_irqsave(&par->accept_q_lock, flags);
548 	list_del_init(&iucv_sk(sk)->accept_q);
549 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
550 	sk_acceptq_removed(iucv_sk(sk)->parent);
551 	iucv_sk(sk)->parent = NULL;
552 	sock_put(sk);
553 }
554 
555 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
556 {
557 	struct iucv_sock *isk, *n;
558 	struct sock *sk;
559 
560 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
561 		sk = (struct sock *) isk;
562 		lock_sock(sk);
563 
564 		if (sk->sk_state == IUCV_CLOSED) {
565 			iucv_accept_unlink(sk);
566 			release_sock(sk);
567 			continue;
568 		}
569 
570 		if (sk->sk_state == IUCV_CONNECTED ||
571 		    sk->sk_state == IUCV_SEVERED ||
572 		    sk->sk_state == IUCV_DISCONN ||	/* due to PM restore */
573 		    !newsock) {
574 			iucv_accept_unlink(sk);
575 			if (newsock)
576 				sock_graft(sk, newsock);
577 
578 			if (sk->sk_state == IUCV_SEVERED)
579 				sk->sk_state = IUCV_DISCONN;
580 
581 			release_sock(sk);
582 			return sk;
583 		}
584 
585 		release_sock(sk);
586 	}
587 	return NULL;
588 }
589 
590 /* Bind an unbound socket */
591 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
592 			  int addr_len)
593 {
594 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
595 	struct sock *sk = sock->sk;
596 	struct iucv_sock *iucv;
597 	int err;
598 
599 	/* Verify the input sockaddr */
600 	if (!addr || addr->sa_family != AF_IUCV)
601 		return -EINVAL;
602 
603 	lock_sock(sk);
604 	if (sk->sk_state != IUCV_OPEN) {
605 		err = -EBADFD;
606 		goto done;
607 	}
608 
609 	write_lock_bh(&iucv_sk_list.lock);
610 
611 	iucv = iucv_sk(sk);
612 	if (__iucv_get_sock_by_name(sa->siucv_name)) {
613 		err = -EADDRINUSE;
614 		goto done_unlock;
615 	}
616 	if (iucv->path) {
617 		err = 0;
618 		goto done_unlock;
619 	}
620 
621 	/* Bind the socket */
622 	memcpy(iucv->src_name, sa->siucv_name, 8);
623 
624 	/* Copy the user id */
625 	memcpy(iucv->src_user_id, iucv_userid, 8);
626 	sk->sk_state = IUCV_BOUND;
627 	err = 0;
628 
629 done_unlock:
630 	/* Release the socket list lock */
631 	write_unlock_bh(&iucv_sk_list.lock);
632 done:
633 	release_sock(sk);
634 	return err;
635 }
636 
637 /* Automatically bind an unbound socket */
638 static int iucv_sock_autobind(struct sock *sk)
639 {
640 	struct iucv_sock *iucv = iucv_sk(sk);
641 	char query_buffer[80];
642 	char name[12];
643 	int err = 0;
644 
645 	/* Set the userid and name */
646 	cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
647 	if (unlikely(err))
648 		return -EPROTO;
649 
650 	memcpy(iucv->src_user_id, query_buffer, 8);
651 
652 	write_lock_bh(&iucv_sk_list.lock);
653 
654 	sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
655 	while (__iucv_get_sock_by_name(name)) {
656 		sprintf(name, "%08x",
657 			atomic_inc_return(&iucv_sk_list.autobind_name));
658 	}
659 
660 	write_unlock_bh(&iucv_sk_list.lock);
661 
662 	memcpy(&iucv->src_name, name, 8);
663 
664 	return err;
665 }
666 
667 /* Connect an unconnected socket */
668 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
669 			     int alen, int flags)
670 {
671 	struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
672 	struct sock *sk = sock->sk;
673 	struct iucv_sock *iucv;
674 	unsigned char user_data[16];
675 	int err;
676 
677 	if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
678 		return -EINVAL;
679 
680 	if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
681 		return -EBADFD;
682 
683 	if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
684 		return -EINVAL;
685 
686 	if (sk->sk_state == IUCV_OPEN) {
687 		err = iucv_sock_autobind(sk);
688 		if (unlikely(err))
689 			return err;
690 	}
691 
692 	lock_sock(sk);
693 
694 	/* Set the destination information */
695 	memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
696 	memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
697 
698 	high_nmcpy(user_data, sa->siucv_name);
699 	low_nmcpy(user_data, iucv_sk(sk)->src_name);
700 	ASCEBC(user_data, sizeof(user_data));
701 
702 	iucv = iucv_sk(sk);
703 	/* Create path. */
704 	iucv->path = iucv_path_alloc(iucv->msglimit,
705 				     IUCV_IPRMDATA, GFP_KERNEL);
706 	if (!iucv->path) {
707 		err = -ENOMEM;
708 		goto done;
709 	}
710 	err = iucv_path_connect(iucv->path, &af_iucv_handler,
711 				sa->siucv_user_id, NULL, user_data, sk);
712 	if (err) {
713 		iucv_path_free(iucv->path);
714 		iucv->path = NULL;
715 		switch (err) {
716 		case 0x0b:	/* Target communicator is not logged on */
717 			err = -ENETUNREACH;
718 			break;
719 		case 0x0d:	/* Max connections for this guest exceeded */
720 		case 0x0e:	/* Max connections for target guest exceeded */
721 			err = -EAGAIN;
722 			break;
723 		case 0x0f:	/* Missing IUCV authorization */
724 			err = -EACCES;
725 			break;
726 		default:
727 			err = -ECONNREFUSED;
728 			break;
729 		}
730 		goto done;
731 	}
732 
733 	if (sk->sk_state != IUCV_CONNECTED) {
734 		err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
735 							    IUCV_DISCONN),
736 				     sock_sndtimeo(sk, flags & O_NONBLOCK));
737 	}
738 
739 	if (sk->sk_state == IUCV_DISCONN) {
740 		err = -ECONNREFUSED;
741 	}
742 
743 	if (err) {
744 		iucv_path_sever(iucv->path, NULL);
745 		iucv_path_free(iucv->path);
746 		iucv->path = NULL;
747 	}
748 
749 done:
750 	release_sock(sk);
751 	return err;
752 }
753 
754 /* Move a socket into listening state. */
755 static int iucv_sock_listen(struct socket *sock, int backlog)
756 {
757 	struct sock *sk = sock->sk;
758 	int err;
759 
760 	lock_sock(sk);
761 
762 	err = -EINVAL;
763 	if (sk->sk_state != IUCV_BOUND)
764 		goto done;
765 
766 	if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
767 		goto done;
768 
769 	sk->sk_max_ack_backlog = backlog;
770 	sk->sk_ack_backlog = 0;
771 	sk->sk_state = IUCV_LISTEN;
772 	err = 0;
773 
774 done:
775 	release_sock(sk);
776 	return err;
777 }
778 
779 /* Accept a pending connection */
780 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
781 			    int flags)
782 {
783 	DECLARE_WAITQUEUE(wait, current);
784 	struct sock *sk = sock->sk, *nsk;
785 	long timeo;
786 	int err = 0;
787 
788 	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
789 
790 	if (sk->sk_state != IUCV_LISTEN) {
791 		err = -EBADFD;
792 		goto done;
793 	}
794 
795 	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
796 
797 	/* Wait for an incoming connection */
798 	add_wait_queue_exclusive(sk->sk_sleep, &wait);
799 	while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
800 		set_current_state(TASK_INTERRUPTIBLE);
801 		if (!timeo) {
802 			err = -EAGAIN;
803 			break;
804 		}
805 
806 		release_sock(sk);
807 		timeo = schedule_timeout(timeo);
808 		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
809 
810 		if (sk->sk_state != IUCV_LISTEN) {
811 			err = -EBADFD;
812 			break;
813 		}
814 
815 		if (signal_pending(current)) {
816 			err = sock_intr_errno(timeo);
817 			break;
818 		}
819 	}
820 
821 	set_current_state(TASK_RUNNING);
822 	remove_wait_queue(sk->sk_sleep, &wait);
823 
824 	if (err)
825 		goto done;
826 
827 	newsock->state = SS_CONNECTED;
828 
829 done:
830 	release_sock(sk);
831 	return err;
832 }
833 
834 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
835 			     int *len, int peer)
836 {
837 	struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
838 	struct sock *sk = sock->sk;
839 
840 	addr->sa_family = AF_IUCV;
841 	*len = sizeof(struct sockaddr_iucv);
842 
843 	if (peer) {
844 		memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
845 		memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
846 	} else {
847 		memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
848 		memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
849 	}
850 	memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
851 	memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
852 	memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
853 
854 	return 0;
855 }
856 
857 /**
858  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
859  * @path:	IUCV path
860  * @msg:	Pointer to a struct iucv_message
861  * @skb:	The socket data to send, skb->len MUST BE <= 7
862  *
863  * Send the socket data in the parameter list in the iucv message
864  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
865  * list and the socket data len at index 7 (last byte).
866  * See also iucv_msg_length().
867  *
868  * Returns the error code from the iucv_message_send() call.
869  */
870 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
871 			  struct sk_buff *skb)
872 {
873 	u8 prmdata[8];
874 
875 	memcpy(prmdata, (void *) skb->data, skb->len);
876 	prmdata[7] = 0xff - (u8) skb->len;
877 	return iucv_message_send(path, msg, IUCV_IPRMDATA, 0,
878 				 (void *) prmdata, 8);
879 }
880 
881 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
882 			     struct msghdr *msg, size_t len)
883 {
884 	struct sock *sk = sock->sk;
885 	struct iucv_sock *iucv = iucv_sk(sk);
886 	struct sk_buff *skb;
887 	struct iucv_message txmsg;
888 	struct cmsghdr *cmsg;
889 	int cmsg_done;
890 	long timeo;
891 	char user_id[9];
892 	char appl_id[9];
893 	int err;
894 	int noblock = msg->msg_flags & MSG_DONTWAIT;
895 
896 	err = sock_error(sk);
897 	if (err)
898 		return err;
899 
900 	if (msg->msg_flags & MSG_OOB)
901 		return -EOPNOTSUPP;
902 
903 	/* SOCK_SEQPACKET: we do not support segmented records */
904 	if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
905 		return -EOPNOTSUPP;
906 
907 	lock_sock(sk);
908 
909 	if (sk->sk_shutdown & SEND_SHUTDOWN) {
910 		err = -EPIPE;
911 		goto out;
912 	}
913 
914 	/* Return if the socket is not in connected state */
915 	if (sk->sk_state != IUCV_CONNECTED) {
916 		err = -ENOTCONN;
917 		goto out;
918 	}
919 
920 	/* initialize defaults */
921 	cmsg_done   = 0;	/* check for duplicate headers */
922 	txmsg.class = 0;
923 
924 	/* iterate over control messages */
925 	for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
926 		cmsg = CMSG_NXTHDR(msg, cmsg)) {
927 
928 		if (!CMSG_OK(msg, cmsg)) {
929 			err = -EINVAL;
930 			goto out;
931 		}
932 
933 		if (cmsg->cmsg_level != SOL_IUCV)
934 			continue;
935 
936 		if (cmsg->cmsg_type & cmsg_done) {
937 			err = -EINVAL;
938 			goto out;
939 		}
940 		cmsg_done |= cmsg->cmsg_type;
941 
942 		switch (cmsg->cmsg_type) {
943 		case SCM_IUCV_TRGCLS:
944 			if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
945 				err = -EINVAL;
946 				goto out;
947 			}
948 
949 			/* set iucv message target class */
950 			memcpy(&txmsg.class,
951 				(void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
952 
953 			break;
954 
955 		default:
956 			err = -EINVAL;
957 			goto out;
958 			break;
959 		}
960 	}
961 
962 	/* allocate one skb for each iucv message:
963 	 * this is fine for SOCK_SEQPACKET (unless we want to support
964 	 * segmented records using the MSG_EOR flag), but
965 	 * for SOCK_STREAM we might want to improve it in future */
966 	skb = sock_alloc_send_skb(sk, len, noblock, &err);
967 	if (!skb)
968 		goto out;
969 	if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
970 		err = -EFAULT;
971 		goto fail;
972 	}
973 
974 	/* wait if outstanding messages for iucv path has reached */
975 	timeo = sock_sndtimeo(sk, noblock);
976 	err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
977 	if (err)
978 		goto fail;
979 
980 	/* return -ECONNRESET if the socket is no longer connected */
981 	if (sk->sk_state != IUCV_CONNECTED) {
982 		err = -ECONNRESET;
983 		goto fail;
984 	}
985 
986 	/* increment and save iucv message tag for msg_completion cbk */
987 	txmsg.tag = iucv->send_tag++;
988 	memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);
989 	skb_queue_tail(&iucv->send_skb_q, skb);
990 
991 	if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
992 	      && skb->len <= 7) {
993 		err = iucv_send_iprm(iucv->path, &txmsg, skb);
994 
995 		/* on success: there is no message_complete callback
996 		 * for an IPRMDATA msg; remove skb from send queue */
997 		if (err == 0) {
998 			skb_unlink(skb, &iucv->send_skb_q);
999 			kfree_skb(skb);
1000 		}
1001 
1002 		/* this error should never happen since the
1003 		 * IUCV_IPRMDATA path flag is set... sever path */
1004 		if (err == 0x15) {
1005 			iucv_path_sever(iucv->path, NULL);
1006 			skb_unlink(skb, &iucv->send_skb_q);
1007 			err = -EPIPE;
1008 			goto fail;
1009 		}
1010 	} else
1011 		err = iucv_message_send(iucv->path, &txmsg, 0, 0,
1012 					(void *) skb->data, skb->len);
1013 	if (err) {
1014 		if (err == 3) {
1015 			user_id[8] = 0;
1016 			memcpy(user_id, iucv->dst_user_id, 8);
1017 			appl_id[8] = 0;
1018 			memcpy(appl_id, iucv->dst_name, 8);
1019 			pr_err("Application %s on z/VM guest %s"
1020 				" exceeds message limit\n",
1021 				appl_id, user_id);
1022 			err = -EAGAIN;
1023 		} else
1024 			err = -EPIPE;
1025 		skb_unlink(skb, &iucv->send_skb_q);
1026 		goto fail;
1027 	}
1028 
1029 	release_sock(sk);
1030 	return len;
1031 
1032 fail:
1033 	kfree_skb(skb);
1034 out:
1035 	release_sock(sk);
1036 	return err;
1037 }
1038 
1039 /* iucv_fragment_skb() - Fragment a single IUCV message into multiple skb's
1040  *
1041  * Locking: must be called with message_q.lock held
1042  */
1043 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
1044 {
1045 	int dataleft, size, copied = 0;
1046 	struct sk_buff *nskb;
1047 
1048 	dataleft = len;
1049 	while (dataleft) {
1050 		if (dataleft >= sk->sk_rcvbuf / 4)
1051 			size = sk->sk_rcvbuf / 4;
1052 		else
1053 			size = dataleft;
1054 
1055 		nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
1056 		if (!nskb)
1057 			return -ENOMEM;
1058 
1059 		/* copy target class to control buffer of new skb */
1060 		memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);
1061 
1062 		/* copy data fragment */
1063 		memcpy(nskb->data, skb->data + copied, size);
1064 		copied += size;
1065 		dataleft -= size;
1066 
1067 		skb_reset_transport_header(nskb);
1068 		skb_reset_network_header(nskb);
1069 		nskb->len = size;
1070 
1071 		skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
1072 	}
1073 
1074 	return 0;
1075 }
1076 
1077 /* iucv_process_message() - Receive a single outstanding IUCV message
1078  *
1079  * Locking: must be called with message_q.lock held
1080  */
1081 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1082 				 struct iucv_path *path,
1083 				 struct iucv_message *msg)
1084 {
1085 	int rc;
1086 	unsigned int len;
1087 
1088 	len = iucv_msg_length(msg);
1089 
1090 	/* store msg target class in the second 4 bytes of skb ctrl buffer */
1091 	/* Note: the first 4 bytes are reserved for msg tag */
1092 	memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);
1093 
1094 	/* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1095 	if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1096 		if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1097 			skb->data = NULL;
1098 			skb->len = 0;
1099 		}
1100 	} else {
1101 		rc = iucv_message_receive(path, msg, msg->flags & IUCV_IPRMDATA,
1102 					  skb->data, len, NULL);
1103 		if (rc) {
1104 			kfree_skb(skb);
1105 			return;
1106 		}
1107 		/* we need to fragment iucv messages for SOCK_STREAM only;
1108 		 * for SOCK_SEQPACKET, it is only relevant if we support
1109 		 * record segmentation using MSG_EOR (see also recvmsg()) */
1110 		if (sk->sk_type == SOCK_STREAM &&
1111 		    skb->truesize >= sk->sk_rcvbuf / 4) {
1112 			rc = iucv_fragment_skb(sk, skb, len);
1113 			kfree_skb(skb);
1114 			skb = NULL;
1115 			if (rc) {
1116 				iucv_path_sever(path, NULL);
1117 				return;
1118 			}
1119 			skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
1120 		} else {
1121 			skb_reset_transport_header(skb);
1122 			skb_reset_network_header(skb);
1123 			skb->len = len;
1124 		}
1125 	}
1126 
1127 	if (sock_queue_rcv_skb(sk, skb))
1128 		skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1129 }
1130 
1131 /* iucv_process_message_q() - Process outstanding IUCV messages
1132  *
1133  * Locking: must be called with message_q.lock held
1134  */
1135 static void iucv_process_message_q(struct sock *sk)
1136 {
1137 	struct iucv_sock *iucv = iucv_sk(sk);
1138 	struct sk_buff *skb;
1139 	struct sock_msg_q *p, *n;
1140 
1141 	list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1142 		skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1143 		if (!skb)
1144 			break;
1145 		iucv_process_message(sk, skb, p->path, &p->msg);
1146 		list_del(&p->list);
1147 		kfree(p);
1148 		if (!skb_queue_empty(&iucv->backlog_skb_q))
1149 			break;
1150 	}
1151 }
1152 
1153 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1154 			     struct msghdr *msg, size_t len, int flags)
1155 {
1156 	int noblock = flags & MSG_DONTWAIT;
1157 	struct sock *sk = sock->sk;
1158 	struct iucv_sock *iucv = iucv_sk(sk);
1159 	unsigned int copied, rlen;
1160 	struct sk_buff *skb, *rskb, *cskb;
1161 	int err = 0;
1162 
1163 	if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
1164 	    skb_queue_empty(&iucv->backlog_skb_q) &&
1165 	    skb_queue_empty(&sk->sk_receive_queue) &&
1166 	    list_empty(&iucv->message_q.list))
1167 		return 0;
1168 
1169 	if (flags & (MSG_OOB))
1170 		return -EOPNOTSUPP;
1171 
1172 	/* receive/dequeue next skb:
1173 	 * the function understands MSG_PEEK and, thus, does not dequeue skb */
1174 	skb = skb_recv_datagram(sk, flags, noblock, &err);
1175 	if (!skb) {
1176 		if (sk->sk_shutdown & RCV_SHUTDOWN)
1177 			return 0;
1178 		return err;
1179 	}
1180 
1181 	rlen   = skb->len;		/* real length of skb */
1182 	copied = min_t(unsigned int, rlen, len);
1183 
1184 	cskb = skb;
1185 	if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
1186 		if (!(flags & MSG_PEEK))
1187 			skb_queue_head(&sk->sk_receive_queue, skb);
1188 		return -EFAULT;
1189 	}
1190 
1191 	/* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1192 	if (sk->sk_type == SOCK_SEQPACKET) {
1193 		if (copied < rlen)
1194 			msg->msg_flags |= MSG_TRUNC;
1195 		/* each iucv message contains a complete record */
1196 		msg->msg_flags |= MSG_EOR;
1197 	}
1198 
1199 	/* create control message to store iucv msg target class:
1200 	 * get the trgcls from the control buffer of the skb due to
1201 	 * fragmentation of original iucv message. */
1202 	err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1203 			CB_TRGCLS_LEN, CB_TRGCLS(skb));
1204 	if (err) {
1205 		if (!(flags & MSG_PEEK))
1206 			skb_queue_head(&sk->sk_receive_queue, skb);
1207 		return err;
1208 	}
1209 
1210 	/* Mark read part of skb as used */
1211 	if (!(flags & MSG_PEEK)) {
1212 
1213 		/* SOCK_STREAM: re-queue skb if it contains unreceived data */
1214 		if (sk->sk_type == SOCK_STREAM) {
1215 			skb_pull(skb, copied);
1216 			if (skb->len) {
1217 				skb_queue_head(&sk->sk_receive_queue, skb);
1218 				goto done;
1219 			}
1220 		}
1221 
1222 		kfree_skb(skb);
1223 
1224 		/* Queue backlog skbs */
1225 		spin_lock_bh(&iucv->message_q.lock);
1226 		rskb = skb_dequeue(&iucv->backlog_skb_q);
1227 		while (rskb) {
1228 			if (sock_queue_rcv_skb(sk, rskb)) {
1229 				skb_queue_head(&iucv->backlog_skb_q,
1230 						rskb);
1231 				break;
1232 			} else {
1233 				rskb = skb_dequeue(&iucv->backlog_skb_q);
1234 			}
1235 		}
1236 		if (skb_queue_empty(&iucv->backlog_skb_q)) {
1237 			if (!list_empty(&iucv->message_q.list))
1238 				iucv_process_message_q(sk);
1239 		}
1240 		spin_unlock_bh(&iucv->message_q.lock);
1241 	}
1242 
1243 done:
1244 	/* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1245 	if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1246 		copied = rlen;
1247 
1248 	return copied;
1249 }
1250 
1251 static inline unsigned int iucv_accept_poll(struct sock *parent)
1252 {
1253 	struct iucv_sock *isk, *n;
1254 	struct sock *sk;
1255 
1256 	list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1257 		sk = (struct sock *) isk;
1258 
1259 		if (sk->sk_state == IUCV_CONNECTED)
1260 			return POLLIN | POLLRDNORM;
1261 	}
1262 
1263 	return 0;
1264 }
1265 
1266 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1267 			    poll_table *wait)
1268 {
1269 	struct sock *sk = sock->sk;
1270 	unsigned int mask = 0;
1271 
1272 	sock_poll_wait(file, sk->sk_sleep, wait);
1273 
1274 	if (sk->sk_state == IUCV_LISTEN)
1275 		return iucv_accept_poll(sk);
1276 
1277 	if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1278 		mask |= POLLERR;
1279 
1280 	if (sk->sk_shutdown & RCV_SHUTDOWN)
1281 		mask |= POLLRDHUP;
1282 
1283 	if (sk->sk_shutdown == SHUTDOWN_MASK)
1284 		mask |= POLLHUP;
1285 
1286 	if (!skb_queue_empty(&sk->sk_receive_queue) ||
1287 	    (sk->sk_shutdown & RCV_SHUTDOWN))
1288 		mask |= POLLIN | POLLRDNORM;
1289 
1290 	if (sk->sk_state == IUCV_CLOSED)
1291 		mask |= POLLHUP;
1292 
1293 	if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
1294 		mask |= POLLIN;
1295 
1296 	if (sock_writeable(sk))
1297 		mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1298 	else
1299 		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1300 
1301 	return mask;
1302 }
1303 
1304 static int iucv_sock_shutdown(struct socket *sock, int how)
1305 {
1306 	struct sock *sk = sock->sk;
1307 	struct iucv_sock *iucv = iucv_sk(sk);
1308 	struct iucv_message txmsg;
1309 	int err = 0;
1310 
1311 	how++;
1312 
1313 	if ((how & ~SHUTDOWN_MASK) || !how)
1314 		return -EINVAL;
1315 
1316 	lock_sock(sk);
1317 	switch (sk->sk_state) {
1318 	case IUCV_DISCONN:
1319 	case IUCV_CLOSING:
1320 	case IUCV_SEVERED:
1321 	case IUCV_CLOSED:
1322 		err = -ENOTCONN;
1323 		goto fail;
1324 
1325 	default:
1326 		sk->sk_shutdown |= how;
1327 		break;
1328 	}
1329 
1330 	if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1331 		txmsg.class = 0;
1332 		txmsg.tag = 0;
1333 		err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
1334 					(void *) iprm_shutdown, 8);
1335 		if (err) {
1336 			switch (err) {
1337 			case 1:
1338 				err = -ENOTCONN;
1339 				break;
1340 			case 2:
1341 				err = -ECONNRESET;
1342 				break;
1343 			default:
1344 				err = -ENOTCONN;
1345 				break;
1346 			}
1347 		}
1348 	}
1349 
1350 	if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1351 		err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
1352 		if (err)
1353 			err = -ENOTCONN;
1354 
1355 		skb_queue_purge(&sk->sk_receive_queue);
1356 	}
1357 
1358 	/* Wake up anyone sleeping in poll */
1359 	sk->sk_state_change(sk);
1360 
1361 fail:
1362 	release_sock(sk);
1363 	return err;
1364 }
1365 
1366 static int iucv_sock_release(struct socket *sock)
1367 {
1368 	struct sock *sk = sock->sk;
1369 	int err = 0;
1370 
1371 	if (!sk)
1372 		return 0;
1373 
1374 	iucv_sock_close(sk);
1375 
1376 	/* Unregister with IUCV base support */
1377 	if (iucv_sk(sk)->path) {
1378 		iucv_path_sever(iucv_sk(sk)->path, NULL);
1379 		iucv_path_free(iucv_sk(sk)->path);
1380 		iucv_sk(sk)->path = NULL;
1381 	}
1382 
1383 	sock_orphan(sk);
1384 	iucv_sock_kill(sk);
1385 	return err;
1386 }
1387 
1388 /* getsockopt and setsockopt */
1389 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1390 				char __user *optval, unsigned int optlen)
1391 {
1392 	struct sock *sk = sock->sk;
1393 	struct iucv_sock *iucv = iucv_sk(sk);
1394 	int val;
1395 	int rc;
1396 
1397 	if (level != SOL_IUCV)
1398 		return -ENOPROTOOPT;
1399 
1400 	if (optlen < sizeof(int))
1401 		return -EINVAL;
1402 
1403 	if (get_user(val, (int __user *) optval))
1404 		return -EFAULT;
1405 
1406 	rc = 0;
1407 
1408 	lock_sock(sk);
1409 	switch (optname) {
1410 	case SO_IPRMDATA_MSG:
1411 		if (val)
1412 			iucv->flags |= IUCV_IPRMDATA;
1413 		else
1414 			iucv->flags &= ~IUCV_IPRMDATA;
1415 		break;
1416 	case SO_MSGLIMIT:
1417 		switch (sk->sk_state) {
1418 		case IUCV_OPEN:
1419 		case IUCV_BOUND:
1420 			if (val < 1 || val > (u16)(~0))
1421 				rc = -EINVAL;
1422 			else
1423 				iucv->msglimit = val;
1424 			break;
1425 		default:
1426 			rc = -EINVAL;
1427 			break;
1428 		}
1429 		break;
1430 	default:
1431 		rc = -ENOPROTOOPT;
1432 		break;
1433 	}
1434 	release_sock(sk);
1435 
1436 	return rc;
1437 }
1438 
1439 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1440 				char __user *optval, int __user *optlen)
1441 {
1442 	struct sock *sk = sock->sk;
1443 	struct iucv_sock *iucv = iucv_sk(sk);
1444 	int val, len;
1445 
1446 	if (level != SOL_IUCV)
1447 		return -ENOPROTOOPT;
1448 
1449 	if (get_user(len, optlen))
1450 		return -EFAULT;
1451 
1452 	if (len < 0)
1453 		return -EINVAL;
1454 
1455 	len = min_t(unsigned int, len, sizeof(int));
1456 
1457 	switch (optname) {
1458 	case SO_IPRMDATA_MSG:
1459 		val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1460 		break;
1461 	case SO_MSGLIMIT:
1462 		lock_sock(sk);
1463 		val = (iucv->path != NULL) ? iucv->path->msglim	/* connected */
1464 					   : iucv->msglimit;	/* default */
1465 		release_sock(sk);
1466 		break;
1467 	default:
1468 		return -ENOPROTOOPT;
1469 	}
1470 
1471 	if (put_user(len, optlen))
1472 		return -EFAULT;
1473 	if (copy_to_user(optval, &val, len))
1474 		return -EFAULT;
1475 
1476 	return 0;
1477 }
1478 
1479 
1480 /* Callback wrappers - called from iucv base support */
1481 static int iucv_callback_connreq(struct iucv_path *path,
1482 				 u8 ipvmid[8], u8 ipuser[16])
1483 {
1484 	unsigned char user_data[16];
1485 	unsigned char nuser_data[16];
1486 	unsigned char src_name[8];
1487 	struct hlist_node *node;
1488 	struct sock *sk, *nsk;
1489 	struct iucv_sock *iucv, *niucv;
1490 	int err;
1491 
1492 	memcpy(src_name, ipuser, 8);
1493 	EBCASC(src_name, 8);
1494 	/* Find out if this path belongs to af_iucv. */
1495 	read_lock(&iucv_sk_list.lock);
1496 	iucv = NULL;
1497 	sk = NULL;
1498 	sk_for_each(sk, node, &iucv_sk_list.head)
1499 		if (sk->sk_state == IUCV_LISTEN &&
1500 		    !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1501 			/*
1502 			 * Found a listening socket with
1503 			 * src_name == ipuser[0-7].
1504 			 */
1505 			iucv = iucv_sk(sk);
1506 			break;
1507 		}
1508 	read_unlock(&iucv_sk_list.lock);
1509 	if (!iucv)
1510 		/* No socket found, not one of our paths. */
1511 		return -EINVAL;
1512 
1513 	bh_lock_sock(sk);
1514 
1515 	/* Check if parent socket is listening */
1516 	low_nmcpy(user_data, iucv->src_name);
1517 	high_nmcpy(user_data, iucv->dst_name);
1518 	ASCEBC(user_data, sizeof(user_data));
1519 	if (sk->sk_state != IUCV_LISTEN) {
1520 		err = iucv_path_sever(path, user_data);
1521 		iucv_path_free(path);
1522 		goto fail;
1523 	}
1524 
1525 	/* Check for backlog size */
1526 	if (sk_acceptq_is_full(sk)) {
1527 		err = iucv_path_sever(path, user_data);
1528 		iucv_path_free(path);
1529 		goto fail;
1530 	}
1531 
1532 	/* Create the new socket */
1533 	nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1534 	if (!nsk) {
1535 		err = iucv_path_sever(path, user_data);
1536 		iucv_path_free(path);
1537 		goto fail;
1538 	}
1539 
1540 	niucv = iucv_sk(nsk);
1541 	iucv_sock_init(nsk, sk);
1542 
1543 	/* Set the new iucv_sock */
1544 	memcpy(niucv->dst_name, ipuser + 8, 8);
1545 	EBCASC(niucv->dst_name, 8);
1546 	memcpy(niucv->dst_user_id, ipvmid, 8);
1547 	memcpy(niucv->src_name, iucv->src_name, 8);
1548 	memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1549 	niucv->path = path;
1550 
1551 	/* Call iucv_accept */
1552 	high_nmcpy(nuser_data, ipuser + 8);
1553 	memcpy(nuser_data + 8, niucv->src_name, 8);
1554 	ASCEBC(nuser_data + 8, 8);
1555 
1556 	/* set message limit for path based on msglimit of accepting socket */
1557 	niucv->msglimit = iucv->msglimit;
1558 	path->msglim = iucv->msglimit;
1559 	err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
1560 	if (err) {
1561 		err = iucv_path_sever(path, user_data);
1562 		iucv_path_free(path);
1563 		iucv_sock_kill(nsk);
1564 		goto fail;
1565 	}
1566 
1567 	iucv_accept_enqueue(sk, nsk);
1568 
1569 	/* Wake up accept */
1570 	nsk->sk_state = IUCV_CONNECTED;
1571 	sk->sk_data_ready(sk, 1);
1572 	err = 0;
1573 fail:
1574 	bh_unlock_sock(sk);
1575 	return 0;
1576 }
1577 
1578 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1579 {
1580 	struct sock *sk = path->private;
1581 
1582 	sk->sk_state = IUCV_CONNECTED;
1583 	sk->sk_state_change(sk);
1584 }
1585 
1586 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1587 {
1588 	struct sock *sk = path->private;
1589 	struct iucv_sock *iucv = iucv_sk(sk);
1590 	struct sk_buff *skb;
1591 	struct sock_msg_q *save_msg;
1592 	int len;
1593 
1594 	if (sk->sk_shutdown & RCV_SHUTDOWN) {
1595 		iucv_message_reject(path, msg);
1596 		return;
1597 	}
1598 
1599 	spin_lock(&iucv->message_q.lock);
1600 
1601 	if (!list_empty(&iucv->message_q.list) ||
1602 	    !skb_queue_empty(&iucv->backlog_skb_q))
1603 		goto save_message;
1604 
1605 	len = atomic_read(&sk->sk_rmem_alloc);
1606 	len += iucv_msg_length(msg) + sizeof(struct sk_buff);
1607 	if (len > sk->sk_rcvbuf)
1608 		goto save_message;
1609 
1610 	skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1611 	if (!skb)
1612 		goto save_message;
1613 
1614 	iucv_process_message(sk, skb, path, msg);
1615 	goto out_unlock;
1616 
1617 save_message:
1618 	save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1619 	if (!save_msg)
1620 		return;
1621 	save_msg->path = path;
1622 	save_msg->msg = *msg;
1623 
1624 	list_add_tail(&save_msg->list, &iucv->message_q.list);
1625 
1626 out_unlock:
1627 	spin_unlock(&iucv->message_q.lock);
1628 }
1629 
1630 static void iucv_callback_txdone(struct iucv_path *path,
1631 				 struct iucv_message *msg)
1632 {
1633 	struct sock *sk = path->private;
1634 	struct sk_buff *this = NULL;
1635 	struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1636 	struct sk_buff *list_skb = list->next;
1637 	unsigned long flags;
1638 
1639 	if (!skb_queue_empty(list)) {
1640 		spin_lock_irqsave(&list->lock, flags);
1641 
1642 		while (list_skb != (struct sk_buff *)list) {
1643 			if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {
1644 				this = list_skb;
1645 				break;
1646 			}
1647 			list_skb = list_skb->next;
1648 		}
1649 		if (this)
1650 			__skb_unlink(this, list);
1651 
1652 		spin_unlock_irqrestore(&list->lock, flags);
1653 
1654 		if (this) {
1655 			kfree_skb(this);
1656 			/* wake up any process waiting for sending */
1657 			iucv_sock_wake_msglim(sk);
1658 		}
1659 	}
1660 	BUG_ON(!this);
1661 
1662 	if (sk->sk_state == IUCV_CLOSING) {
1663 		if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1664 			sk->sk_state = IUCV_CLOSED;
1665 			sk->sk_state_change(sk);
1666 		}
1667 	}
1668 
1669 }
1670 
1671 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1672 {
1673 	struct sock *sk = path->private;
1674 
1675 	if (!list_empty(&iucv_sk(sk)->accept_q))
1676 		sk->sk_state = IUCV_SEVERED;
1677 	else
1678 		sk->sk_state = IUCV_DISCONN;
1679 
1680 	sk->sk_state_change(sk);
1681 }
1682 
1683 /* called if the other communication side shuts down its RECV direction;
1684  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1685  */
1686 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1687 {
1688 	struct sock *sk = path->private;
1689 
1690 	bh_lock_sock(sk);
1691 	if (sk->sk_state != IUCV_CLOSED) {
1692 		sk->sk_shutdown |= SEND_SHUTDOWN;
1693 		sk->sk_state_change(sk);
1694 	}
1695 	bh_unlock_sock(sk);
1696 }
1697 
1698 static const struct proto_ops iucv_sock_ops = {
1699 	.family		= PF_IUCV,
1700 	.owner		= THIS_MODULE,
1701 	.release	= iucv_sock_release,
1702 	.bind		= iucv_sock_bind,
1703 	.connect	= iucv_sock_connect,
1704 	.listen		= iucv_sock_listen,
1705 	.accept		= iucv_sock_accept,
1706 	.getname	= iucv_sock_getname,
1707 	.sendmsg	= iucv_sock_sendmsg,
1708 	.recvmsg	= iucv_sock_recvmsg,
1709 	.poll		= iucv_sock_poll,
1710 	.ioctl		= sock_no_ioctl,
1711 	.mmap		= sock_no_mmap,
1712 	.socketpair	= sock_no_socketpair,
1713 	.shutdown	= iucv_sock_shutdown,
1714 	.setsockopt	= iucv_sock_setsockopt,
1715 	.getsockopt	= iucv_sock_getsockopt,
1716 };
1717 
1718 static const struct net_proto_family iucv_sock_family_ops = {
1719 	.family	= AF_IUCV,
1720 	.owner	= THIS_MODULE,
1721 	.create	= iucv_sock_create,
1722 };
1723 
1724 static int __init afiucv_init(void)
1725 {
1726 	int err;
1727 
1728 	if (!MACHINE_IS_VM) {
1729 		pr_err("The af_iucv module cannot be loaded"
1730 		       " without z/VM\n");
1731 		err = -EPROTONOSUPPORT;
1732 		goto out;
1733 	}
1734 	cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1735 	if (unlikely(err)) {
1736 		WARN_ON(err);
1737 		err = -EPROTONOSUPPORT;
1738 		goto out;
1739 	}
1740 
1741 	err = iucv_register(&af_iucv_handler, 0);
1742 	if (err)
1743 		goto out;
1744 	err = proto_register(&iucv_proto, 0);
1745 	if (err)
1746 		goto out_iucv;
1747 	err = sock_register(&iucv_sock_family_ops);
1748 	if (err)
1749 		goto out_proto;
1750 	/* establish dummy device */
1751 	err = driver_register(&af_iucv_driver);
1752 	if (err)
1753 		goto out_sock;
1754 	af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
1755 	if (!af_iucv_dev) {
1756 		err = -ENOMEM;
1757 		goto out_driver;
1758 	}
1759 	dev_set_name(af_iucv_dev, "af_iucv");
1760 	af_iucv_dev->bus = &iucv_bus;
1761 	af_iucv_dev->parent = iucv_root;
1762 	af_iucv_dev->release = (void (*)(struct device *))kfree;
1763 	af_iucv_dev->driver = &af_iucv_driver;
1764 	err = device_register(af_iucv_dev);
1765 	if (err)
1766 		goto out_driver;
1767 
1768 	return 0;
1769 
1770 out_driver:
1771 	driver_unregister(&af_iucv_driver);
1772 out_sock:
1773 	sock_unregister(PF_IUCV);
1774 out_proto:
1775 	proto_unregister(&iucv_proto);
1776 out_iucv:
1777 	iucv_unregister(&af_iucv_handler, 0);
1778 out:
1779 	return err;
1780 }
1781 
1782 static void __exit afiucv_exit(void)
1783 {
1784 	device_unregister(af_iucv_dev);
1785 	driver_unregister(&af_iucv_driver);
1786 	sock_unregister(PF_IUCV);
1787 	proto_unregister(&iucv_proto);
1788 	iucv_unregister(&af_iucv_handler, 0);
1789 }
1790 
1791 module_init(afiucv_init);
1792 module_exit(afiucv_exit);
1793 
1794 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1795 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1796 MODULE_VERSION(VERSION);
1797 MODULE_LICENSE("GPL");
1798 MODULE_ALIAS_NETPROTO(PF_IUCV);
1799