[AF_IUCV]: postpone receival of iucv-packets
[linux-2.6.git] / net / iucv / af_iucv.c
1 /*
2  *  linux/net/iucv/af_iucv.c
3  *
4  *  IUCV protocol stack for Linux on zSeries
5  *
6  *  Copyright 2006 IBM Corporation
7  *
8  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
9  */
10
11 #include <linux/module.h>
12 #include <linux/types.h>
13 #include <linux/list.h>
14 #include <linux/errno.h>
15 #include <linux/kernel.h>
16 #include <linux/sched.h>
17 #include <linux/slab.h>
18 #include <linux/skbuff.h>
19 #include <linux/init.h>
20 #include <linux/poll.h>
21 #include <net/sock.h>
22 #include <asm/ebcdic.h>
23 #include <asm/cpcmd.h>
24 #include <linux/kmod.h>
25
26 #include <net/iucv/iucv.h>
27 #include <net/iucv/af_iucv.h>
28
29 #define CONFIG_IUCV_SOCK_DEBUG 1
30
31 #define IPRMDATA 0x80
32 #define VERSION "1.0"
33
34 static char iucv_userid[80];
35
36 static 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 void iucv_sock_kill(struct sock *sk);
45 static void iucv_sock_close(struct sock *sk);
46
47 /* Call Back functions */
48 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
49 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
50 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
51 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
52                                  u8 ipuser[16]);
53 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
54
55 static struct iucv_sock_list iucv_sk_list = {
56         .lock = RW_LOCK_UNLOCKED,
57         .autobind_name = ATOMIC_INIT(0)
58 };
59
60 static struct iucv_handler af_iucv_handler = {
61         .path_pending     = iucv_callback_connreq,
62         .path_complete    = iucv_callback_connack,
63         .path_severed     = iucv_callback_connrej,
64         .message_pending  = iucv_callback_rx,
65         .message_complete = iucv_callback_txdone
66 };
67
68 static inline void high_nmcpy(unsigned char *dst, char *src)
69 {
70        memcpy(dst, src, 8);
71 }
72
73 static inline void low_nmcpy(unsigned char *dst, char *src)
74 {
75        memcpy(&dst[8], src, 8);
76 }
77
78 /* Timers */
79 static void iucv_sock_timeout(unsigned long arg)
80 {
81         struct sock *sk = (struct sock *)arg;
82
83         bh_lock_sock(sk);
84         sk->sk_err = ETIMEDOUT;
85         sk->sk_state_change(sk);
86         bh_unlock_sock(sk);
87
88         iucv_sock_kill(sk);
89         sock_put(sk);
90 }
91
92 static void iucv_sock_clear_timer(struct sock *sk)
93 {
94         sk_stop_timer(sk, &sk->sk_timer);
95 }
96
97 static void iucv_sock_init_timer(struct sock *sk)
98 {
99         init_timer(&sk->sk_timer);
100         sk->sk_timer.function = iucv_sock_timeout;
101         sk->sk_timer.data = (unsigned long)sk;
102 }
103
104 static struct sock *__iucv_get_sock_by_name(char *nm)
105 {
106         struct sock *sk;
107         struct hlist_node *node;
108
109         sk_for_each(sk, node, &iucv_sk_list.head)
110                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
111                         return sk;
112
113         return NULL;
114 }
115
116 static void iucv_sock_destruct(struct sock *sk)
117 {
118         skb_queue_purge(&sk->sk_receive_queue);
119         skb_queue_purge(&sk->sk_write_queue);
120 }
121
122 /* Cleanup Listen */
123 static void iucv_sock_cleanup_listen(struct sock *parent)
124 {
125         struct sock *sk;
126
127         /* Close non-accepted connections */
128         while ((sk = iucv_accept_dequeue(parent, NULL))) {
129                 iucv_sock_close(sk);
130                 iucv_sock_kill(sk);
131         }
132
133         parent->sk_state = IUCV_CLOSED;
134         sock_set_flag(parent, SOCK_ZAPPED);
135 }
136
137 /* Kill socket */
138 static void iucv_sock_kill(struct sock *sk)
139 {
140         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
141                 return;
142
143         iucv_sock_unlink(&iucv_sk_list, sk);
144         sock_set_flag(sk, SOCK_DEAD);
145         sock_put(sk);
146 }
147
148 /* Close an IUCV socket */
149 static void iucv_sock_close(struct sock *sk)
150 {
151         unsigned char user_data[16];
152         struct iucv_sock *iucv = iucv_sk(sk);
153         int err;
154         unsigned long timeo;
155
156         iucv_sock_clear_timer(sk);
157         lock_sock(sk);
158
159         switch (sk->sk_state) {
160         case IUCV_LISTEN:
161                 iucv_sock_cleanup_listen(sk);
162                 break;
163
164         case IUCV_CONNECTED:
165         case IUCV_DISCONN:
166                 err = 0;
167
168                 sk->sk_state = IUCV_CLOSING;
169                 sk->sk_state_change(sk);
170
171                 if (!skb_queue_empty(&iucv->send_skb_q)) {
172                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
173                                 timeo = sk->sk_lingertime;
174                         else
175                                 timeo = IUCV_DISCONN_TIMEOUT;
176                         err = iucv_sock_wait_state(sk, IUCV_CLOSED, 0, timeo);
177                 }
178
179                 sk->sk_state = IUCV_CLOSED;
180                 sk->sk_state_change(sk);
181
182                 if (iucv->path) {
183                         low_nmcpy(user_data, iucv->src_name);
184                         high_nmcpy(user_data, iucv->dst_name);
185                         ASCEBC(user_data, sizeof(user_data));
186                         err = iucv_path_sever(iucv->path, user_data);
187                         iucv_path_free(iucv->path);
188                         iucv->path = NULL;
189                 }
190
191                 sk->sk_err = ECONNRESET;
192                 sk->sk_state_change(sk);
193
194                 skb_queue_purge(&iucv->send_skb_q);
195                 skb_queue_purge(&iucv->backlog_skb_q);
196
197                 sock_set_flag(sk, SOCK_ZAPPED);
198                 break;
199
200         default:
201                 sock_set_flag(sk, SOCK_ZAPPED);
202                 break;
203         }
204
205         release_sock(sk);
206         iucv_sock_kill(sk);
207 }
208
209 static void iucv_sock_init(struct sock *sk, struct sock *parent)
210 {
211         if (parent)
212                 sk->sk_type = parent->sk_type;
213 }
214
215 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
216 {
217         struct sock *sk;
218
219         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto, 1);
220         if (!sk)
221                 return NULL;
222
223         sock_init_data(sock, sk);
224         INIT_LIST_HEAD(&iucv_sk(sk)->accept_q);
225         spin_lock_init(&iucv_sk(sk)->accept_q_lock);
226         skb_queue_head_init(&iucv_sk(sk)->send_skb_q);
227         INIT_LIST_HEAD(&iucv_sk(sk)->message_q.list);
228         spin_lock_init(&iucv_sk(sk)->message_q.lock);
229         skb_queue_head_init(&iucv_sk(sk)->backlog_skb_q);
230         iucv_sk(sk)->send_tag = 0;
231
232         sk->sk_destruct = iucv_sock_destruct;
233         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
234         sk->sk_allocation = GFP_DMA;
235
236         sock_reset_flag(sk, SOCK_ZAPPED);
237
238         sk->sk_protocol = proto;
239         sk->sk_state    = IUCV_OPEN;
240
241         iucv_sock_init_timer(sk);
242
243         iucv_sock_link(&iucv_sk_list, sk);
244         return sk;
245 }
246
247 /* Create an IUCV socket */
248 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol)
249 {
250         struct sock *sk;
251
252         if (sock->type != SOCK_STREAM)
253                 return -ESOCKTNOSUPPORT;
254
255         sock->state = SS_UNCONNECTED;
256         sock->ops = &iucv_sock_ops;
257
258         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
259         if (!sk)
260                 return -ENOMEM;
261
262         iucv_sock_init(sk, NULL);
263
264         return 0;
265 }
266
267 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
268 {
269         write_lock_bh(&l->lock);
270         sk_add_node(sk, &l->head);
271         write_unlock_bh(&l->lock);
272 }
273
274 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
275 {
276         write_lock_bh(&l->lock);
277         sk_del_node_init(sk);
278         write_unlock_bh(&l->lock);
279 }
280
281 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
282 {
283         unsigned long flags;
284         struct iucv_sock *par = iucv_sk(parent);
285
286         sock_hold(sk);
287         spin_lock_irqsave(&par->accept_q_lock, flags);
288         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
289         spin_unlock_irqrestore(&par->accept_q_lock, flags);
290         iucv_sk(sk)->parent = parent;
291         parent->sk_ack_backlog++;
292 }
293
294 void iucv_accept_unlink(struct sock *sk)
295 {
296         unsigned long flags;
297         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
298
299         spin_lock_irqsave(&par->accept_q_lock, flags);
300         list_del_init(&iucv_sk(sk)->accept_q);
301         spin_unlock_irqrestore(&par->accept_q_lock, flags);
302         iucv_sk(sk)->parent->sk_ack_backlog--;
303         iucv_sk(sk)->parent = NULL;
304         sock_put(sk);
305 }
306
307 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
308 {
309         struct iucv_sock *isk, *n;
310         struct sock *sk;
311
312         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
313                 sk = (struct sock *) isk;
314                 lock_sock(sk);
315
316                 if (sk->sk_state == IUCV_CLOSED) {
317                         iucv_accept_unlink(sk);
318                         release_sock(sk);
319                         continue;
320                 }
321
322                 if (sk->sk_state == IUCV_CONNECTED ||
323                     sk->sk_state == IUCV_SEVERED ||
324                     !newsock) {
325                         iucv_accept_unlink(sk);
326                         if (newsock)
327                                 sock_graft(sk, newsock);
328
329                         if (sk->sk_state == IUCV_SEVERED)
330                                 sk->sk_state = IUCV_DISCONN;
331
332                         release_sock(sk);
333                         return sk;
334                 }
335
336                 release_sock(sk);
337         }
338         return NULL;
339 }
340
341 int iucv_sock_wait_state(struct sock *sk, int state, int state2,
342                          unsigned long timeo)
343 {
344         DECLARE_WAITQUEUE(wait, current);
345         int err = 0;
346
347         add_wait_queue(sk->sk_sleep, &wait);
348         while (sk->sk_state != state && sk->sk_state != state2) {
349                 set_current_state(TASK_INTERRUPTIBLE);
350
351                 if (!timeo) {
352                         err = -EAGAIN;
353                         break;
354                 }
355
356                 if (signal_pending(current)) {
357                         err = sock_intr_errno(timeo);
358                         break;
359                 }
360
361                 release_sock(sk);
362                 timeo = schedule_timeout(timeo);
363                 lock_sock(sk);
364
365                 err = sock_error(sk);
366                 if (err)
367                         break;
368         }
369         set_current_state(TASK_RUNNING);
370         remove_wait_queue(sk->sk_sleep, &wait);
371         return err;
372 }
373
374 /* Bind an unbound socket */
375 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
376                           int addr_len)
377 {
378         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
379         struct sock *sk = sock->sk;
380         struct iucv_sock *iucv;
381         int err;
382
383         /* Verify the input sockaddr */
384         if (!addr || addr->sa_family != AF_IUCV)
385                 return -EINVAL;
386
387         lock_sock(sk);
388         if (sk->sk_state != IUCV_OPEN) {
389                 err = -EBADFD;
390                 goto done;
391         }
392
393         write_lock_bh(&iucv_sk_list.lock);
394
395         iucv = iucv_sk(sk);
396         if (__iucv_get_sock_by_name(sa->siucv_name)) {
397                 err = -EADDRINUSE;
398                 goto done_unlock;
399         }
400         if (iucv->path) {
401                 err = 0;
402                 goto done_unlock;
403         }
404
405         /* Bind the socket */
406         memcpy(iucv->src_name, sa->siucv_name, 8);
407
408         /* Copy the user id */
409         memcpy(iucv->src_user_id, iucv_userid, 8);
410         sk->sk_state = IUCV_BOUND;
411         err = 0;
412
413 done_unlock:
414         /* Release the socket list lock */
415         write_unlock_bh(&iucv_sk_list.lock);
416 done:
417         release_sock(sk);
418         return err;
419 }
420
421 /* Automatically bind an unbound socket */
422 static int iucv_sock_autobind(struct sock *sk)
423 {
424         struct iucv_sock *iucv = iucv_sk(sk);
425         char query_buffer[80];
426         char name[12];
427         int err = 0;
428
429         /* Set the userid and name */
430         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
431         if (unlikely(err))
432                 return -EPROTO;
433
434         memcpy(iucv->src_user_id, query_buffer, 8);
435
436         write_lock_bh(&iucv_sk_list.lock);
437
438         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
439         while (__iucv_get_sock_by_name(name)) {
440                 sprintf(name, "%08x",
441                         atomic_inc_return(&iucv_sk_list.autobind_name));
442         }
443
444         write_unlock_bh(&iucv_sk_list.lock);
445
446         memcpy(&iucv->src_name, name, 8);
447
448         return err;
449 }
450
451 /* Connect an unconnected socket */
452 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
453                              int alen, int flags)
454 {
455         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
456         struct sock *sk = sock->sk;
457         struct iucv_sock *iucv;
458         unsigned char user_data[16];
459         int err;
460
461         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
462                 return -EINVAL;
463
464         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
465                 return -EBADFD;
466
467         if (sk->sk_type != SOCK_STREAM)
468                 return -EINVAL;
469
470         iucv = iucv_sk(sk);
471
472         if (sk->sk_state == IUCV_OPEN) {
473                 err = iucv_sock_autobind(sk);
474                 if (unlikely(err))
475                         return err;
476         }
477
478         lock_sock(sk);
479
480         /* Set the destination information */
481         memcpy(iucv_sk(sk)->dst_user_id, sa->siucv_user_id, 8);
482         memcpy(iucv_sk(sk)->dst_name, sa->siucv_name, 8);
483
484         high_nmcpy(user_data, sa->siucv_name);
485         low_nmcpy(user_data, iucv_sk(sk)->src_name);
486         ASCEBC(user_data, sizeof(user_data));
487
488         iucv = iucv_sk(sk);
489         /* Create path. */
490         iucv->path = iucv_path_alloc(IUCV_QUEUELEN_DEFAULT,
491                                      IPRMDATA, GFP_KERNEL);
492         err = iucv_path_connect(iucv->path, &af_iucv_handler,
493                                 sa->siucv_user_id, NULL, user_data, sk);
494         if (err) {
495                 iucv_path_free(iucv->path);
496                 iucv->path = NULL;
497                 err = -ECONNREFUSED;
498                 goto done;
499         }
500
501         if (sk->sk_state != IUCV_CONNECTED) {
502                 err = iucv_sock_wait_state(sk, IUCV_CONNECTED, IUCV_DISCONN,
503                                 sock_sndtimeo(sk, flags & O_NONBLOCK));
504         }
505
506         if (sk->sk_state == IUCV_DISCONN) {
507                 release_sock(sk);
508                 return -ECONNREFUSED;
509         }
510 done:
511         release_sock(sk);
512         return err;
513 }
514
515 /* Move a socket into listening state. */
516 static int iucv_sock_listen(struct socket *sock, int backlog)
517 {
518         struct sock *sk = sock->sk;
519         int err;
520
521         lock_sock(sk);
522
523         err = -EINVAL;
524         if (sk->sk_state != IUCV_BOUND || sock->type != SOCK_STREAM)
525                 goto done;
526
527         sk->sk_max_ack_backlog = backlog;
528         sk->sk_ack_backlog = 0;
529         sk->sk_state = IUCV_LISTEN;
530         err = 0;
531
532 done:
533         release_sock(sk);
534         return err;
535 }
536
537 /* Accept a pending connection */
538 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
539                             int flags)
540 {
541         DECLARE_WAITQUEUE(wait, current);
542         struct sock *sk = sock->sk, *nsk;
543         long timeo;
544         int err = 0;
545
546         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
547
548         if (sk->sk_state != IUCV_LISTEN) {
549                 err = -EBADFD;
550                 goto done;
551         }
552
553         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
554
555         /* Wait for an incoming connection */
556         add_wait_queue_exclusive(sk->sk_sleep, &wait);
557         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
558                 set_current_state(TASK_INTERRUPTIBLE);
559                 if (!timeo) {
560                         err = -EAGAIN;
561                         break;
562                 }
563
564                 release_sock(sk);
565                 timeo = schedule_timeout(timeo);
566                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
567
568                 if (sk->sk_state != IUCV_LISTEN) {
569                         err = -EBADFD;
570                         break;
571                 }
572
573                 if (signal_pending(current)) {
574                         err = sock_intr_errno(timeo);
575                         break;
576                 }
577         }
578
579         set_current_state(TASK_RUNNING);
580         remove_wait_queue(sk->sk_sleep, &wait);
581
582         if (err)
583                 goto done;
584
585         newsock->state = SS_CONNECTED;
586
587 done:
588         release_sock(sk);
589         return err;
590 }
591
592 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
593                              int *len, int peer)
594 {
595         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
596         struct sock *sk = sock->sk;
597
598         addr->sa_family = AF_IUCV;
599         *len = sizeof(struct sockaddr_iucv);
600
601         if (peer) {
602                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->dst_user_id, 8);
603                 memcpy(siucv->siucv_name, &iucv_sk(sk)->dst_name, 8);
604         } else {
605                 memcpy(siucv->siucv_user_id, iucv_sk(sk)->src_user_id, 8);
606                 memcpy(siucv->siucv_name, iucv_sk(sk)->src_name, 8);
607         }
608         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
609         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
610         memset(siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
611
612         return 0;
613 }
614
615 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
616                              struct msghdr *msg, size_t len)
617 {
618         struct sock *sk = sock->sk;
619         struct iucv_sock *iucv = iucv_sk(sk);
620         struct sk_buff *skb;
621         struct iucv_message txmsg;
622         int err;
623
624         err = sock_error(sk);
625         if (err)
626                 return err;
627
628         if (msg->msg_flags & MSG_OOB)
629                 return -EOPNOTSUPP;
630
631         lock_sock(sk);
632
633         if (sk->sk_shutdown & SEND_SHUTDOWN) {
634                 err = -EPIPE;
635                 goto out;
636         }
637
638         if (sk->sk_state == IUCV_CONNECTED) {
639                 if (!(skb = sock_alloc_send_skb(sk, len,
640                                                 msg->msg_flags & MSG_DONTWAIT,
641                                                 &err)))
642                         goto out;
643
644                 if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
645                         err = -EFAULT;
646                         goto fail;
647                 }
648
649                 txmsg.class = 0;
650                 txmsg.tag = iucv->send_tag++;
651                 memcpy(skb->cb, &txmsg.tag, 4);
652                 skb_queue_tail(&iucv->send_skb_q, skb);
653                 err = iucv_message_send(iucv->path, &txmsg, 0, 0,
654                                         (void *) skb->data, skb->len);
655                 if (err) {
656                         if (err == 3)
657                                 printk(KERN_ERR "AF_IUCV msg limit exceeded\n");
658                         skb_unlink(skb, &iucv->send_skb_q);
659                         err = -EPIPE;
660                         goto fail;
661                 }
662
663         } else {
664                 err = -ENOTCONN;
665                 goto out;
666         }
667
668         release_sock(sk);
669         return len;
670
671 fail:
672         kfree_skb(skb);
673 out:
674         release_sock(sk);
675         return err;
676 }
677
678 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
679 {
680         int dataleft, size, copied = 0;
681         struct sk_buff *nskb;
682
683         dataleft = len;
684         while (dataleft) {
685                 if (dataleft >= sk->sk_rcvbuf / 4)
686                         size = sk->sk_rcvbuf / 4;
687                 else
688                         size = dataleft;
689
690                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
691                 if (!nskb)
692                         return -ENOMEM;
693
694                 memcpy(nskb->data, skb->data + copied, size);
695                 copied += size;
696                 dataleft -= size;
697
698                 skb_reset_transport_header(nskb);
699                 skb_reset_network_header(nskb);
700                 nskb->len = size;
701
702                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
703         }
704
705         return 0;
706 }
707
708 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
709                                  struct iucv_path *path,
710                                  struct iucv_message *msg)
711 {
712         int rc;
713
714         if (msg->flags & IPRMDATA) {
715                 skb->data = NULL;
716                 skb->len = 0;
717         } else {
718                 rc = iucv_message_receive(path, msg, 0, skb->data,
719                                           msg->length, NULL);
720                 if (rc) {
721                         kfree_skb(skb);
722                         return;
723                 }
724                 if (skb->truesize >= sk->sk_rcvbuf / 4) {
725                         rc = iucv_fragment_skb(sk, skb, msg->length);
726                         kfree_skb(skb);
727                         skb = NULL;
728                         if (rc) {
729                                 iucv_path_sever(path, NULL);
730                                 return;
731                         }
732                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
733                 } else {
734                         skb_reset_transport_header(skb);
735                         skb_reset_network_header(skb);
736                         skb->len = msg->length;
737                 }
738         }
739
740         if (sock_queue_rcv_skb(sk, skb))
741                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
742 }
743
744 static void iucv_process_message_q(struct sock *sk)
745 {
746         struct iucv_sock *iucv = iucv_sk(sk);
747         struct sk_buff *skb;
748         struct sock_msg_q *p, *n;
749
750         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
751                 skb = alloc_skb(p->msg.length, GFP_ATOMIC | GFP_DMA);
752                 if (!skb)
753                         break;
754                 iucv_process_message(sk, skb, p->path, &p->msg);
755                 list_del(&p->list);
756                 kfree(p);
757                 if (!skb_queue_empty(&iucv->backlog_skb_q))
758                         break;
759         }
760 }
761
762 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
763                              struct msghdr *msg, size_t len, int flags)
764 {
765         int noblock = flags & MSG_DONTWAIT;
766         struct sock *sk = sock->sk;
767         struct iucv_sock *iucv = iucv_sk(sk);
768         int target, copied = 0;
769         struct sk_buff *skb, *rskb, *cskb;
770         int err = 0;
771
772         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
773             skb_queue_empty(&iucv->backlog_skb_q) &&
774             skb_queue_empty(&sk->sk_receive_queue) &&
775             list_empty(&iucv->message_q.list))
776                 return 0;
777
778         if (flags & (MSG_OOB))
779                 return -EOPNOTSUPP;
780
781         target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
782
783         skb = skb_recv_datagram(sk, flags, noblock, &err);
784         if (!skb) {
785                 if (sk->sk_shutdown & RCV_SHUTDOWN)
786                         return 0;
787                 return err;
788         }
789
790         copied = min_t(unsigned int, skb->len, len);
791
792         cskb = skb;
793         if (memcpy_toiovec(msg->msg_iov, cskb->data, copied)) {
794                 skb_queue_head(&sk->sk_receive_queue, skb);
795                 if (copied == 0)
796                         return -EFAULT;
797                 goto done;
798         }
799
800         len -= copied;
801
802         /* Mark read part of skb as used */
803         if (!(flags & MSG_PEEK)) {
804                 skb_pull(skb, copied);
805
806                 if (skb->len) {
807                         skb_queue_head(&sk->sk_receive_queue, skb);
808                         goto done;
809                 }
810
811                 kfree_skb(skb);
812
813                 /* Queue backlog skbs */
814                 rskb = skb_dequeue(&iucv->backlog_skb_q);
815                 while (rskb) {
816                         if (sock_queue_rcv_skb(sk, rskb)) {
817                                 skb_queue_head(&iucv->backlog_skb_q,
818                                                 rskb);
819                                 break;
820                         } else {
821                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
822                         }
823                 }
824                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
825                         spin_lock_bh(&iucv->message_q.lock);
826                         if (!list_empty(&iucv->message_q.list))
827                                 iucv_process_message_q(sk);
828                         spin_unlock_bh(&iucv->message_q.lock);
829                 }
830
831         } else
832                 skb_queue_head(&sk->sk_receive_queue, skb);
833
834 done:
835         return err ? : copied;
836 }
837
838 static inline unsigned int iucv_accept_poll(struct sock *parent)
839 {
840         struct iucv_sock *isk, *n;
841         struct sock *sk;
842
843         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
844                 sk = (struct sock *) isk;
845
846                 if (sk->sk_state == IUCV_CONNECTED)
847                         return POLLIN | POLLRDNORM;
848         }
849
850         return 0;
851 }
852
853 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
854                             poll_table *wait)
855 {
856         struct sock *sk = sock->sk;
857         unsigned int mask = 0;
858
859         poll_wait(file, sk->sk_sleep, wait);
860
861         if (sk->sk_state == IUCV_LISTEN)
862                 return iucv_accept_poll(sk);
863
864         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
865                 mask |= POLLERR;
866
867         if (sk->sk_shutdown & RCV_SHUTDOWN)
868                 mask |= POLLRDHUP;
869
870         if (sk->sk_shutdown == SHUTDOWN_MASK)
871                 mask |= POLLHUP;
872
873         if (!skb_queue_empty(&sk->sk_receive_queue) ||
874             (sk->sk_shutdown & RCV_SHUTDOWN))
875                 mask |= POLLIN | POLLRDNORM;
876
877         if (sk->sk_state == IUCV_CLOSED)
878                 mask |= POLLHUP;
879
880         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
881                 mask |= POLLIN;
882
883         if (sock_writeable(sk))
884                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
885         else
886                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
887
888         return mask;
889 }
890
891 static int iucv_sock_shutdown(struct socket *sock, int how)
892 {
893         struct sock *sk = sock->sk;
894         struct iucv_sock *iucv = iucv_sk(sk);
895         struct iucv_message txmsg;
896         int err = 0;
897         u8 prmmsg[8] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
898
899         how++;
900
901         if ((how & ~SHUTDOWN_MASK) || !how)
902                 return -EINVAL;
903
904         lock_sock(sk);
905         switch (sk->sk_state) {
906         case IUCV_CLOSED:
907                 err = -ENOTCONN;
908                 goto fail;
909
910         default:
911                 sk->sk_shutdown |= how;
912                 break;
913         }
914
915         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
916                 txmsg.class = 0;
917                 txmsg.tag = 0;
918                 err = iucv_message_send(iucv->path, &txmsg, IUCV_IPRMDATA, 0,
919                                         (void *) prmmsg, 8);
920                 if (err) {
921                         switch (err) {
922                         case 1:
923                                 err = -ENOTCONN;
924                                 break;
925                         case 2:
926                                 err = -ECONNRESET;
927                                 break;
928                         default:
929                                 err = -ENOTCONN;
930                                 break;
931                         }
932                 }
933         }
934
935         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
936                 err = iucv_path_quiesce(iucv_sk(sk)->path, NULL);
937                 if (err)
938                         err = -ENOTCONN;
939
940                 skb_queue_purge(&sk->sk_receive_queue);
941         }
942
943         /* Wake up anyone sleeping in poll */
944         sk->sk_state_change(sk);
945
946 fail:
947         release_sock(sk);
948         return err;
949 }
950
951 static int iucv_sock_release(struct socket *sock)
952 {
953         struct sock *sk = sock->sk;
954         int err = 0;
955
956         if (!sk)
957                 return 0;
958
959         iucv_sock_close(sk);
960
961         /* Unregister with IUCV base support */
962         if (iucv_sk(sk)->path) {
963                 iucv_path_sever(iucv_sk(sk)->path, NULL);
964                 iucv_path_free(iucv_sk(sk)->path);
965                 iucv_sk(sk)->path = NULL;
966         }
967
968         sock_orphan(sk);
969         iucv_sock_kill(sk);
970         return err;
971 }
972
973 /* Callback wrappers - called from iucv base support */
974 static int iucv_callback_connreq(struct iucv_path *path,
975                                  u8 ipvmid[8], u8 ipuser[16])
976 {
977         unsigned char user_data[16];
978         unsigned char nuser_data[16];
979         unsigned char src_name[8];
980         struct hlist_node *node;
981         struct sock *sk, *nsk;
982         struct iucv_sock *iucv, *niucv;
983         int err;
984
985         memcpy(src_name, ipuser, 8);
986         EBCASC(src_name, 8);
987         /* Find out if this path belongs to af_iucv. */
988         read_lock(&iucv_sk_list.lock);
989         iucv = NULL;
990         sk = NULL;
991         sk_for_each(sk, node, &iucv_sk_list.head)
992                 if (sk->sk_state == IUCV_LISTEN &&
993                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
994                         /*
995                          * Found a listening socket with
996                          * src_name == ipuser[0-7].
997                          */
998                         iucv = iucv_sk(sk);
999                         break;
1000                 }
1001         read_unlock(&iucv_sk_list.lock);
1002         if (!iucv)
1003                 /* No socket found, not one of our paths. */
1004                 return -EINVAL;
1005
1006         bh_lock_sock(sk);
1007
1008         /* Check if parent socket is listening */
1009         low_nmcpy(user_data, iucv->src_name);
1010         high_nmcpy(user_data, iucv->dst_name);
1011         ASCEBC(user_data, sizeof(user_data));
1012         if (sk->sk_state != IUCV_LISTEN) {
1013                 err = iucv_path_sever(path, user_data);
1014                 goto fail;
1015         }
1016
1017         /* Check for backlog size */
1018         if (sk_acceptq_is_full(sk)) {
1019                 err = iucv_path_sever(path, user_data);
1020                 goto fail;
1021         }
1022
1023         /* Create the new socket */
1024         nsk = iucv_sock_alloc(NULL, SOCK_STREAM, GFP_ATOMIC);
1025         if (!nsk) {
1026                 err = iucv_path_sever(path, user_data);
1027                 goto fail;
1028         }
1029
1030         niucv = iucv_sk(nsk);
1031         iucv_sock_init(nsk, sk);
1032
1033         /* Set the new iucv_sock */
1034         memcpy(niucv->dst_name, ipuser + 8, 8);
1035         EBCASC(niucv->dst_name, 8);
1036         memcpy(niucv->dst_user_id, ipvmid, 8);
1037         memcpy(niucv->src_name, iucv->src_name, 8);
1038         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1039         niucv->path = path;
1040
1041         /* Call iucv_accept */
1042         high_nmcpy(nuser_data, ipuser + 8);
1043         memcpy(nuser_data + 8, niucv->src_name, 8);
1044         ASCEBC(nuser_data + 8, 8);
1045
1046         path->msglim = IUCV_QUEUELEN_DEFAULT;
1047         err = iucv_path_accept(path, &af_iucv_handler, nuser_data, nsk);
1048         if (err) {
1049                 err = iucv_path_sever(path, user_data);
1050                 goto fail;
1051         }
1052
1053         iucv_accept_enqueue(sk, nsk);
1054
1055         /* Wake up accept */
1056         nsk->sk_state = IUCV_CONNECTED;
1057         sk->sk_data_ready(sk, 1);
1058         err = 0;
1059 fail:
1060         bh_unlock_sock(sk);
1061         return 0;
1062 }
1063
1064 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1065 {
1066         struct sock *sk = path->private;
1067
1068         sk->sk_state = IUCV_CONNECTED;
1069         sk->sk_state_change(sk);
1070 }
1071
1072 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1073 {
1074         struct sock *sk = path->private;
1075         struct iucv_sock *iucv = iucv_sk(sk);
1076         struct sk_buff *skb;
1077         struct sock_msg_q *save_msg;
1078         int len;
1079
1080         if (sk->sk_shutdown & RCV_SHUTDOWN)
1081                 return;
1082
1083         if (!list_empty(&iucv->message_q.list) ||
1084             !skb_queue_empty(&iucv->backlog_skb_q))
1085                 goto save_message;
1086
1087         len = atomic_read(&sk->sk_rmem_alloc);
1088         len += msg->length + sizeof(struct sk_buff);
1089         if (len > sk->sk_rcvbuf)
1090                 goto save_message;
1091
1092         skb = alloc_skb(msg->length, GFP_ATOMIC | GFP_DMA);
1093         if (!skb)
1094                 goto save_message;
1095
1096         spin_lock(&iucv->message_q.lock);
1097         iucv_process_message(sk, skb, path, msg);
1098         spin_unlock(&iucv->message_q.lock);
1099
1100         return;
1101
1102 save_message:
1103         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1104         save_msg->path = path;
1105         save_msg->msg = *msg;
1106
1107         spin_lock(&iucv->message_q.lock);
1108         list_add_tail(&save_msg->list, &iucv->message_q.list);
1109         spin_unlock(&iucv->message_q.lock);
1110 }
1111
1112 static void iucv_callback_txdone(struct iucv_path *path,
1113                                  struct iucv_message *msg)
1114 {
1115         struct sock *sk = path->private;
1116         struct sk_buff *this;
1117         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1118         struct sk_buff *list_skb = list->next;
1119         unsigned long flags;
1120
1121         if (list_skb) {
1122                 spin_lock_irqsave(&list->lock, flags);
1123
1124                 do {
1125                         this = list_skb;
1126                         list_skb = list_skb->next;
1127                 } while (memcmp(&msg->tag, this->cb, 4) && list_skb);
1128
1129                 spin_unlock_irqrestore(&list->lock, flags);
1130
1131                 skb_unlink(this, &iucv_sk(sk)->send_skb_q);
1132                 kfree_skb(this);
1133         }
1134
1135         if (sk->sk_state == IUCV_CLOSING) {
1136                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1137                         sk->sk_state = IUCV_CLOSED;
1138                         sk->sk_state_change(sk);
1139                 }
1140         }
1141
1142 }
1143
1144 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1145 {
1146         struct sock *sk = path->private;
1147
1148         if (!list_empty(&iucv_sk(sk)->accept_q))
1149                 sk->sk_state = IUCV_SEVERED;
1150         else
1151                 sk->sk_state = IUCV_DISCONN;
1152
1153         sk->sk_state_change(sk);
1154 }
1155
1156 static struct proto_ops iucv_sock_ops = {
1157         .family         = PF_IUCV,
1158         .owner          = THIS_MODULE,
1159         .release        = iucv_sock_release,
1160         .bind           = iucv_sock_bind,
1161         .connect        = iucv_sock_connect,
1162         .listen         = iucv_sock_listen,
1163         .accept         = iucv_sock_accept,
1164         .getname        = iucv_sock_getname,
1165         .sendmsg        = iucv_sock_sendmsg,
1166         .recvmsg        = iucv_sock_recvmsg,
1167         .poll           = iucv_sock_poll,
1168         .ioctl          = sock_no_ioctl,
1169         .mmap           = sock_no_mmap,
1170         .socketpair     = sock_no_socketpair,
1171         .shutdown       = iucv_sock_shutdown,
1172         .setsockopt     = sock_no_setsockopt,
1173         .getsockopt     = sock_no_getsockopt
1174 };
1175
1176 static struct net_proto_family iucv_sock_family_ops = {
1177         .family = AF_IUCV,
1178         .owner  = THIS_MODULE,
1179         .create = iucv_sock_create,
1180 };
1181
1182 static int __init afiucv_init(void)
1183 {
1184         int err;
1185
1186         if (!MACHINE_IS_VM) {
1187                 printk(KERN_ERR "AF_IUCV connection needs VM as base\n");
1188                 err = -EPROTONOSUPPORT;
1189                 goto out;
1190         }
1191         cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
1192         if (unlikely(err)) {
1193                 printk(KERN_ERR "AF_IUCV needs the VM userid\n");
1194                 err = -EPROTONOSUPPORT;
1195                 goto out;
1196         }
1197
1198         err = iucv_register(&af_iucv_handler, 0);
1199         if (err)
1200                 goto out;
1201         err = proto_register(&iucv_proto, 0);
1202         if (err)
1203                 goto out_iucv;
1204         err = sock_register(&iucv_sock_family_ops);
1205         if (err)
1206                 goto out_proto;
1207         printk(KERN_INFO "AF_IUCV lowlevel driver initialized\n");
1208         return 0;
1209
1210 out_proto:
1211         proto_unregister(&iucv_proto);
1212 out_iucv:
1213         iucv_unregister(&af_iucv_handler, 0);
1214 out:
1215         return err;
1216 }
1217
1218 static void __exit afiucv_exit(void)
1219 {
1220         sock_unregister(PF_IUCV);
1221         proto_unregister(&iucv_proto);
1222         iucv_unregister(&af_iucv_handler, 0);
1223
1224         printk(KERN_INFO "AF_IUCV lowlevel driver unloaded\n");
1225 }
1226
1227 module_init(afiucv_init);
1228 module_exit(afiucv_exit);
1229
1230 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
1231 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
1232 MODULE_VERSION(VERSION);
1233 MODULE_LICENSE("GPL");
1234 MODULE_ALIAS_NETPROTO(PF_IUCV);