net: remove skb_orphan_try()
[pandora-kernel.git] / net / iucv / af_iucv.c
1 /*
2  *  IUCV protocol stack for Linux on zSeries
3  *
4  *  Copyright IBM Corp. 2006, 2009
5  *
6  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
7  *              Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
8  *  PM functions:
9  *              Ursula Braun <ursula.braun@de.ibm.com>
10  */
11
12 #define KMSG_COMPONENT "af_iucv"
13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
14
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <linux/list.h>
18 #include <linux/errno.h>
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
21 #include <linux/slab.h>
22 #include <linux/skbuff.h>
23 #include <linux/init.h>
24 #include <linux/poll.h>
25 #include <net/sock.h>
26 #include <asm/ebcdic.h>
27 #include <asm/cpcmd.h>
28 #include <linux/kmod.h>
29
30 #include <net/iucv/af_iucv.h>
31
32 #define VERSION "1.2"
33
34 static char iucv_userid[80];
35
36 static const struct proto_ops iucv_sock_ops;
37
38 static struct proto iucv_proto = {
39         .name           = "AF_IUCV",
40         .owner          = THIS_MODULE,
41         .obj_size       = sizeof(struct iucv_sock),
42 };
43
44 static struct iucv_interface *pr_iucv;
45
46 /* special AF_IUCV IPRM messages */
47 static const u8 iprm_shutdown[8] =
48         {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
49
50 #define TRGCLS_SIZE     (sizeof(((struct iucv_message *)0)->class))
51
52 /* macros to set/get socket control buffer at correct offset */
53 #define CB_TAG(skb)     ((skb)->cb)             /* iucv message tag */
54 #define CB_TAG_LEN      (sizeof(((struct iucv_message *) 0)->tag))
55 #define CB_TRGCLS(skb)  ((skb)->cb + CB_TAG_LEN) /* iucv msg target class */
56 #define CB_TRGCLS_LEN   (TRGCLS_SIZE)
57
58 #define __iucv_sock_wait(sk, condition, timeo, ret)                     \
59 do {                                                                    \
60         DEFINE_WAIT(__wait);                                            \
61         long __timeo = timeo;                                           \
62         ret = 0;                                                        \
63         prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE);     \
64         while (!(condition)) {                                          \
65                 if (!__timeo) {                                         \
66                         ret = -EAGAIN;                                  \
67                         break;                                          \
68                 }                                                       \
69                 if (signal_pending(current)) {                          \
70                         ret = sock_intr_errno(__timeo);                 \
71                         break;                                          \
72                 }                                                       \
73                 release_sock(sk);                                       \
74                 __timeo = schedule_timeout(__timeo);                    \
75                 lock_sock(sk);                                          \
76                 ret = sock_error(sk);                                   \
77                 if (ret)                                                \
78                         break;                                          \
79         }                                                               \
80         finish_wait(sk_sleep(sk), &__wait);                             \
81 } while (0)
82
83 #define iucv_sock_wait(sk, condition, timeo)                            \
84 ({                                                                      \
85         int __ret = 0;                                                  \
86         if (!(condition))                                               \
87                 __iucv_sock_wait(sk, condition, timeo, __ret);          \
88         __ret;                                                          \
89 })
90
91 static void iucv_sock_kill(struct sock *sk);
92 static void iucv_sock_close(struct sock *sk);
93
94 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
95         struct packet_type *pt, struct net_device *orig_dev);
96 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
97                    struct sk_buff *skb, u8 flags);
98 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
99
100 /* Call Back functions */
101 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
102 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
103 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
104 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
105                                  u8 ipuser[16]);
106 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
107 static void iucv_callback_shutdown(struct iucv_path *, u8 ipuser[16]);
108
109 static struct iucv_sock_list iucv_sk_list = {
110         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
111         .autobind_name = ATOMIC_INIT(0)
112 };
113
114 static struct iucv_handler af_iucv_handler = {
115         .path_pending     = iucv_callback_connreq,
116         .path_complete    = iucv_callback_connack,
117         .path_severed     = iucv_callback_connrej,
118         .message_pending  = iucv_callback_rx,
119         .message_complete = iucv_callback_txdone,
120         .path_quiesced    = iucv_callback_shutdown,
121 };
122
123 static inline void high_nmcpy(unsigned char *dst, char *src)
124 {
125        memcpy(dst, src, 8);
126 }
127
128 static inline void low_nmcpy(unsigned char *dst, char *src)
129 {
130        memcpy(&dst[8], src, 8);
131 }
132
133 static int afiucv_pm_prepare(struct device *dev)
134 {
135 #ifdef CONFIG_PM_DEBUG
136         printk(KERN_WARNING "afiucv_pm_prepare\n");
137 #endif
138         return 0;
139 }
140
141 static void afiucv_pm_complete(struct device *dev)
142 {
143 #ifdef CONFIG_PM_DEBUG
144         printk(KERN_WARNING "afiucv_pm_complete\n");
145 #endif
146 }
147
148 /**
149  * afiucv_pm_freeze() - Freeze PM callback
150  * @dev:        AFIUCV dummy device
151  *
152  * Sever all established IUCV communication pathes
153  */
154 static int afiucv_pm_freeze(struct device *dev)
155 {
156         struct iucv_sock *iucv;
157         struct sock *sk;
158         struct hlist_node *node;
159         int err = 0;
160
161 #ifdef CONFIG_PM_DEBUG
162         printk(KERN_WARNING "afiucv_pm_freeze\n");
163 #endif
164         read_lock(&iucv_sk_list.lock);
165         sk_for_each(sk, node, &iucv_sk_list.head) {
166                 iucv = iucv_sk(sk);
167                 skb_queue_purge(&iucv->send_skb_q);
168                 skb_queue_purge(&iucv->backlog_skb_q);
169                 switch (sk->sk_state) {
170                 case IUCV_SEVERED:
171                 case IUCV_DISCONN:
172                 case IUCV_CLOSING:
173                 case IUCV_CONNECTED:
174                         if (iucv->path) {
175                                 err = pr_iucv->path_sever(iucv->path, NULL);
176                                 iucv_path_free(iucv->path);
177                                 iucv->path = NULL;
178                         }
179                         break;
180                 case IUCV_OPEN:
181                 case IUCV_BOUND:
182                 case IUCV_LISTEN:
183                 case IUCV_CLOSED:
184                 default:
185                         break;
186                 }
187         }
188         read_unlock(&iucv_sk_list.lock);
189         return err;
190 }
191
192 /**
193  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
194  * @dev:        AFIUCV dummy device
195  *
196  * socket clean up after freeze
197  */
198 static int afiucv_pm_restore_thaw(struct device *dev)
199 {
200         struct sock *sk;
201         struct hlist_node *node;
202
203 #ifdef CONFIG_PM_DEBUG
204         printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
205 #endif
206         read_lock(&iucv_sk_list.lock);
207         sk_for_each(sk, node, &iucv_sk_list.head) {
208                 switch (sk->sk_state) {
209                 case IUCV_CONNECTED:
210                         sk->sk_err = EPIPE;
211                         sk->sk_state = IUCV_DISCONN;
212                         sk->sk_state_change(sk);
213                         break;
214                 case IUCV_DISCONN:
215                 case IUCV_SEVERED:
216                 case IUCV_CLOSING:
217                 case IUCV_LISTEN:
218                 case IUCV_BOUND:
219                 case IUCV_OPEN:
220                 default:
221                         break;
222                 }
223         }
224         read_unlock(&iucv_sk_list.lock);
225         return 0;
226 }
227
228 static const struct dev_pm_ops afiucv_pm_ops = {
229         .prepare = afiucv_pm_prepare,
230         .complete = afiucv_pm_complete,
231         .freeze = afiucv_pm_freeze,
232         .thaw = afiucv_pm_restore_thaw,
233         .restore = afiucv_pm_restore_thaw,
234 };
235
236 static struct device_driver af_iucv_driver = {
237         .owner = THIS_MODULE,
238         .name = "afiucv",
239         .bus  = NULL,
240         .pm   = &afiucv_pm_ops,
241 };
242
243 /* dummy device used as trigger for PM functions */
244 static struct device *af_iucv_dev;
245
246 /**
247  * iucv_msg_length() - Returns the length of an iucv message.
248  * @msg:        Pointer to struct iucv_message, MUST NOT be NULL
249  *
250  * The function returns the length of the specified iucv message @msg of data
251  * stored in a buffer and of data stored in the parameter list (PRMDATA).
252  *
253  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
254  * data:
255  *      PRMDATA[0..6]   socket data (max 7 bytes);
256  *      PRMDATA[7]      socket data length value (len is 0xff - PRMDATA[7])
257  *
258  * The socket data length is computed by subtracting the socket data length
259  * value from 0xFF.
260  * If the socket data len is greater 7, then PRMDATA can be used for special
261  * notifications (see iucv_sock_shutdown); and further,
262  * if the socket data len is > 7, the function returns 8.
263  *
264  * Use this function to allocate socket buffers to store iucv message data.
265  */
266 static inline size_t iucv_msg_length(struct iucv_message *msg)
267 {
268         size_t datalen;
269
270         if (msg->flags & IUCV_IPRMDATA) {
271                 datalen = 0xff - msg->rmmsg[7];
272                 return (datalen < 8) ? datalen : 8;
273         }
274         return msg->length;
275 }
276
277 /**
278  * iucv_sock_in_state() - check for specific states
279  * @sk:         sock structure
280  * @state:      first iucv sk state
281  * @state:      second iucv sk state
282  *
283  * Returns true if the socket in either in the first or second state.
284  */
285 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
286 {
287         return (sk->sk_state == state || sk->sk_state == state2);
288 }
289
290 /**
291  * iucv_below_msglim() - function to check if messages can be sent
292  * @sk:         sock structure
293  *
294  * Returns true if the send queue length is lower than the message limit.
295  * Always returns true if the socket is not connected (no iucv path for
296  * checking the message limit).
297  */
298 static inline int iucv_below_msglim(struct sock *sk)
299 {
300         struct iucv_sock *iucv = iucv_sk(sk);
301
302         if (sk->sk_state != IUCV_CONNECTED)
303                 return 1;
304         if (iucv->transport == AF_IUCV_TRANS_IUCV)
305                 return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
306         else
307                 return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
308                         (atomic_read(&iucv->pendings) <= 0));
309 }
310
311 /**
312  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
313  */
314 static void iucv_sock_wake_msglim(struct sock *sk)
315 {
316         struct socket_wq *wq;
317
318         rcu_read_lock();
319         wq = rcu_dereference(sk->sk_wq);
320         if (wq_has_sleeper(wq))
321                 wake_up_interruptible_all(&wq->wait);
322         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
323         rcu_read_unlock();
324 }
325
326 /**
327  * afiucv_hs_send() - send a message through HiperSockets transport
328  */
329 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
330                    struct sk_buff *skb, u8 flags)
331 {
332         struct net *net = sock_net(sock);
333         struct iucv_sock *iucv = iucv_sk(sock);
334         struct af_iucv_trans_hdr *phs_hdr;
335         struct sk_buff *nskb;
336         int err, confirm_recv = 0;
337
338         memset(skb->head, 0, ETH_HLEN);
339         phs_hdr = (struct af_iucv_trans_hdr *)skb_push(skb,
340                                         sizeof(struct af_iucv_trans_hdr));
341         skb_reset_mac_header(skb);
342         skb_reset_network_header(skb);
343         skb_push(skb, ETH_HLEN);
344         skb_reset_mac_header(skb);
345         memset(phs_hdr, 0, sizeof(struct af_iucv_trans_hdr));
346
347         phs_hdr->magic = ETH_P_AF_IUCV;
348         phs_hdr->version = 1;
349         phs_hdr->flags = flags;
350         if (flags == AF_IUCV_FLAG_SYN)
351                 phs_hdr->window = iucv->msglimit;
352         else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
353                 confirm_recv = atomic_read(&iucv->msg_recv);
354                 phs_hdr->window = confirm_recv;
355                 if (confirm_recv)
356                         phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
357         }
358         memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
359         memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
360         memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
361         memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
362         ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
363         ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
364         ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
365         ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
366         if (imsg)
367                 memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
368
369         rcu_read_lock();
370         skb->dev = dev_get_by_index_rcu(net, sock->sk_bound_dev_if);
371         rcu_read_unlock();
372         if (!skb->dev)
373                 return -ENODEV;
374         if (!(skb->dev->flags & IFF_UP))
375                 return -ENETDOWN;
376         if (skb->len > skb->dev->mtu) {
377                 if (sock->sk_type == SOCK_SEQPACKET)
378                         return -EMSGSIZE;
379                 else
380                         skb_trim(skb, skb->dev->mtu);
381         }
382         skb->protocol = ETH_P_AF_IUCV;
383         nskb = skb_clone(skb, GFP_ATOMIC);
384         if (!nskb)
385                 return -ENOMEM;
386         skb_queue_tail(&iucv->send_skb_q, nskb);
387         err = dev_queue_xmit(skb);
388         if (err) {
389                 skb_unlink(nskb, &iucv->send_skb_q);
390                 kfree_skb(nskb);
391         } else {
392                 atomic_sub(confirm_recv, &iucv->msg_recv);
393                 WARN_ON(atomic_read(&iucv->msg_recv) < 0);
394         }
395         return err;
396 }
397
398 /* Timers */
399 static void iucv_sock_timeout(unsigned long arg)
400 {
401         struct sock *sk = (struct sock *)arg;
402
403         bh_lock_sock(sk);
404         sk->sk_err = ETIMEDOUT;
405         sk->sk_state_change(sk);
406         bh_unlock_sock(sk);
407
408         iucv_sock_kill(sk);
409         sock_put(sk);
410 }
411
412 static void iucv_sock_clear_timer(struct sock *sk)
413 {
414         sk_stop_timer(sk, &sk->sk_timer);
415 }
416
417 static struct sock *__iucv_get_sock_by_name(char *nm)
418 {
419         struct sock *sk;
420         struct hlist_node *node;
421
422         sk_for_each(sk, node, &iucv_sk_list.head)
423                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
424                         return sk;
425
426         return NULL;
427 }
428
429 static void iucv_sock_destruct(struct sock *sk)
430 {
431         skb_queue_purge(&sk->sk_receive_queue);
432         skb_queue_purge(&sk->sk_write_queue);
433 }
434
435 /* Cleanup Listen */
436 static void iucv_sock_cleanup_listen(struct sock *parent)
437 {
438         struct sock *sk;
439
440         /* Close non-accepted connections */
441         while ((sk = iucv_accept_dequeue(parent, NULL))) {
442                 iucv_sock_close(sk);
443                 iucv_sock_kill(sk);
444         }
445
446         parent->sk_state = IUCV_CLOSED;
447 }
448
449 /* Kill socket (only if zapped and orphaned) */
450 static void iucv_sock_kill(struct sock *sk)
451 {
452         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
453                 return;
454
455         iucv_sock_unlink(&iucv_sk_list, sk);
456         sock_set_flag(sk, SOCK_DEAD);
457         sock_put(sk);
458 }
459
460 /* Close an IUCV socket */
461 static void iucv_sock_close(struct sock *sk)
462 {
463         unsigned char user_data[16];
464         struct iucv_sock *iucv = iucv_sk(sk);
465         unsigned long timeo;
466         int err, blen;
467         struct sk_buff *skb;
468
469         iucv_sock_clear_timer(sk);
470         lock_sock(sk);
471
472         switch (sk->sk_state) {
473         case IUCV_LISTEN:
474                 iucv_sock_cleanup_listen(sk);
475                 break;
476
477         case IUCV_CONNECTED:
478                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
479                         /* send fin */
480                         blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
481                         skb = sock_alloc_send_skb(sk, blen, 1, &err);
482                         if (skb) {
483                                 skb_reserve(skb,
484                                         sizeof(struct af_iucv_trans_hdr) +
485                                         ETH_HLEN);
486                                 err = afiucv_hs_send(NULL, sk, skb,
487                                                      AF_IUCV_FLAG_FIN);
488                         }
489                         sk->sk_state = IUCV_DISCONN;
490                         sk->sk_state_change(sk);
491                 }
492         case IUCV_DISCONN:
493                 sk->sk_state = IUCV_CLOSING;
494                 sk->sk_state_change(sk);
495
496                 if (!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                 if (iucv->path) {
511                         low_nmcpy(user_data, iucv->src_name);
512                         high_nmcpy(user_data, iucv->dst_name);
513                         ASCEBC(user_data, sizeof(user_data));
514                         pr_iucv->path_sever(iucv->path, user_data);
515                         iucv_path_free(iucv->path);
516                         iucv->path = NULL;
517                 }
518
519                 sk->sk_err = ECONNRESET;
520                 sk->sk_state_change(sk);
521
522                 skb_queue_purge(&iucv->send_skb_q);
523                 skb_queue_purge(&iucv->backlog_skb_q);
524                 break;
525
526         default:
527                 /* nothing to do here */
528                 break;
529         }
530
531         /* mark socket for deletion by iucv_sock_kill() */
532         sock_set_flag(sk, SOCK_ZAPPED);
533
534         release_sock(sk);
535 }
536
537 static void iucv_sock_init(struct sock *sk, struct sock *parent)
538 {
539         if (parent)
540                 sk->sk_type = parent->sk_type;
541 }
542
543 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
544 {
545         struct sock *sk;
546         struct iucv_sock *iucv;
547
548         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
549         if (!sk)
550                 return NULL;
551         iucv = iucv_sk(sk);
552
553         sock_init_data(sock, sk);
554         INIT_LIST_HEAD(&iucv->accept_q);
555         spin_lock_init(&iucv->accept_q_lock);
556         skb_queue_head_init(&iucv->send_skb_q);
557         INIT_LIST_HEAD(&iucv->message_q.list);
558         spin_lock_init(&iucv->message_q.lock);
559         skb_queue_head_init(&iucv->backlog_skb_q);
560         iucv->send_tag = 0;
561         atomic_set(&iucv->pendings, 0);
562         iucv->flags = 0;
563         iucv->msglimit = 0;
564         atomic_set(&iucv->msg_sent, 0);
565         atomic_set(&iucv->msg_recv, 0);
566         iucv->path = NULL;
567         iucv->sk_txnotify = afiucv_hs_callback_txnotify;
568         memset(&iucv->src_user_id , 0, 32);
569         if (pr_iucv)
570                 iucv->transport = AF_IUCV_TRANS_IUCV;
571         else
572                 iucv->transport = AF_IUCV_TRANS_HIPER;
573
574         sk->sk_destruct = iucv_sock_destruct;
575         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
576         sk->sk_allocation = GFP_DMA;
577
578         sock_reset_flag(sk, SOCK_ZAPPED);
579
580         sk->sk_protocol = proto;
581         sk->sk_state    = IUCV_OPEN;
582
583         setup_timer(&sk->sk_timer, iucv_sock_timeout, (unsigned long)sk);
584
585         iucv_sock_link(&iucv_sk_list, sk);
586         return sk;
587 }
588
589 /* Create an IUCV socket */
590 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
591                             int kern)
592 {
593         struct sock *sk;
594
595         if (protocol && protocol != PF_IUCV)
596                 return -EPROTONOSUPPORT;
597
598         sock->state = SS_UNCONNECTED;
599
600         switch (sock->type) {
601         case SOCK_STREAM:
602                 sock->ops = &iucv_sock_ops;
603                 break;
604         case SOCK_SEQPACKET:
605                 /* currently, proto ops can handle both sk types */
606                 sock->ops = &iucv_sock_ops;
607                 break;
608         default:
609                 return -ESOCKTNOSUPPORT;
610         }
611
612         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
613         if (!sk)
614                 return -ENOMEM;
615
616         iucv_sock_init(sk, NULL);
617
618         return 0;
619 }
620
621 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
622 {
623         write_lock_bh(&l->lock);
624         sk_add_node(sk, &l->head);
625         write_unlock_bh(&l->lock);
626 }
627
628 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
629 {
630         write_lock_bh(&l->lock);
631         sk_del_node_init(sk);
632         write_unlock_bh(&l->lock);
633 }
634
635 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
636 {
637         unsigned long flags;
638         struct iucv_sock *par = iucv_sk(parent);
639
640         sock_hold(sk);
641         spin_lock_irqsave(&par->accept_q_lock, flags);
642         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
643         spin_unlock_irqrestore(&par->accept_q_lock, flags);
644         iucv_sk(sk)->parent = parent;
645         sk_acceptq_added(parent);
646 }
647
648 void iucv_accept_unlink(struct sock *sk)
649 {
650         unsigned long flags;
651         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
652
653         spin_lock_irqsave(&par->accept_q_lock, flags);
654         list_del_init(&iucv_sk(sk)->accept_q);
655         spin_unlock_irqrestore(&par->accept_q_lock, flags);
656         sk_acceptq_removed(iucv_sk(sk)->parent);
657         iucv_sk(sk)->parent = NULL;
658         sock_put(sk);
659 }
660
661 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
662 {
663         struct iucv_sock *isk, *n;
664         struct sock *sk;
665
666         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
667                 sk = (struct sock *) isk;
668                 lock_sock(sk);
669
670                 if (sk->sk_state == IUCV_CLOSED) {
671                         iucv_accept_unlink(sk);
672                         release_sock(sk);
673                         continue;
674                 }
675
676                 if (sk->sk_state == IUCV_CONNECTED ||
677                     sk->sk_state == IUCV_SEVERED ||
678                     sk->sk_state == IUCV_DISCONN ||     /* due to PM restore */
679                     !newsock) {
680                         iucv_accept_unlink(sk);
681                         if (newsock)
682                                 sock_graft(sk, newsock);
683
684                         if (sk->sk_state == IUCV_SEVERED)
685                                 sk->sk_state = IUCV_DISCONN;
686
687                         release_sock(sk);
688                         return sk;
689                 }
690
691                 release_sock(sk);
692         }
693         return NULL;
694 }
695
696 /* Bind an unbound socket */
697 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
698                           int addr_len)
699 {
700         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
701         struct sock *sk = sock->sk;
702         struct iucv_sock *iucv;
703         int err = 0;
704         struct net_device *dev;
705         char uid[9];
706
707         /* Verify the input sockaddr */
708         if (!addr || addr->sa_family != AF_IUCV)
709                 return -EINVAL;
710
711         lock_sock(sk);
712         if (sk->sk_state != IUCV_OPEN) {
713                 err = -EBADFD;
714                 goto done;
715         }
716
717         write_lock_bh(&iucv_sk_list.lock);
718
719         iucv = iucv_sk(sk);
720         if (__iucv_get_sock_by_name(sa->siucv_name)) {
721                 err = -EADDRINUSE;
722                 goto done_unlock;
723         }
724         if (iucv->path)
725                 goto done_unlock;
726
727         /* Bind the socket */
728
729         if (pr_iucv)
730                 if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
731                         goto vm_bind; /* VM IUCV transport */
732
733         /* try hiper transport */
734         memcpy(uid, sa->siucv_user_id, sizeof(uid));
735         ASCEBC(uid, 8);
736         rcu_read_lock();
737         for_each_netdev_rcu(&init_net, dev) {
738                 if (!memcmp(dev->perm_addr, uid, 8)) {
739                         memcpy(iucv->src_name, sa->siucv_name, 8);
740                         memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
741                         sock->sk->sk_bound_dev_if = dev->ifindex;
742                         sk->sk_state = IUCV_BOUND;
743                         iucv->transport = AF_IUCV_TRANS_HIPER;
744                         if (!iucv->msglimit)
745                                 iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
746                         rcu_read_unlock();
747                         goto done_unlock;
748                 }
749         }
750         rcu_read_unlock();
751 vm_bind:
752         if (pr_iucv) {
753                 /* use local userid for backward compat */
754                 memcpy(iucv->src_name, sa->siucv_name, 8);
755                 memcpy(iucv->src_user_id, iucv_userid, 8);
756                 sk->sk_state = IUCV_BOUND;
757                 iucv->transport = AF_IUCV_TRANS_IUCV;
758                 if (!iucv->msglimit)
759                         iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
760                 goto done_unlock;
761         }
762         /* found no dev to bind */
763         err = -ENODEV;
764 done_unlock:
765         /* Release the socket list lock */
766         write_unlock_bh(&iucv_sk_list.lock);
767 done:
768         release_sock(sk);
769         return err;
770 }
771
772 /* Automatically bind an unbound socket */
773 static int iucv_sock_autobind(struct sock *sk)
774 {
775         struct iucv_sock *iucv = iucv_sk(sk);
776         char query_buffer[80];
777         char name[12];
778         int err = 0;
779
780         /* Set the userid and name */
781         cpcmd("QUERY USERID", query_buffer, sizeof(query_buffer), &err);
782         if (unlikely(err))
783                 return -EPROTO;
784
785         memcpy(iucv->src_user_id, query_buffer, 8);
786
787         write_lock_bh(&iucv_sk_list.lock);
788
789         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
790         while (__iucv_get_sock_by_name(name)) {
791                 sprintf(name, "%08x",
792                         atomic_inc_return(&iucv_sk_list.autobind_name));
793         }
794
795         write_unlock_bh(&iucv_sk_list.lock);
796
797         memcpy(&iucv->src_name, name, 8);
798
799         if (!iucv->msglimit)
800                 iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
801
802         return err;
803 }
804
805 static int afiucv_hs_connect(struct socket *sock)
806 {
807         struct sock *sk = sock->sk;
808         struct sk_buff *skb;
809         int blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
810         int err = 0;
811
812         /* send syn */
813         skb = sock_alloc_send_skb(sk, blen, 1, &err);
814         if (!skb) {
815                 err = -ENOMEM;
816                 goto done;
817         }
818         skb->dev = NULL;
819         skb_reserve(skb, blen);
820         err = afiucv_hs_send(NULL, sk, skb, AF_IUCV_FLAG_SYN);
821 done:
822         return err;
823 }
824
825 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
826 {
827         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
828         struct sock *sk = sock->sk;
829         struct iucv_sock *iucv = iucv_sk(sk);
830         unsigned char user_data[16];
831         int err;
832
833         high_nmcpy(user_data, sa->siucv_name);
834         low_nmcpy(user_data, iucv->src_name);
835         ASCEBC(user_data, sizeof(user_data));
836
837         /* Create path. */
838         iucv->path = iucv_path_alloc(iucv->msglimit,
839                                      IUCV_IPRMDATA, GFP_KERNEL);
840         if (!iucv->path) {
841                 err = -ENOMEM;
842                 goto done;
843         }
844         err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
845                                     sa->siucv_user_id, NULL, user_data,
846                                     sk);
847         if (err) {
848                 iucv_path_free(iucv->path);
849                 iucv->path = NULL;
850                 switch (err) {
851                 case 0x0b:      /* Target communicator is not logged on */
852                         err = -ENETUNREACH;
853                         break;
854                 case 0x0d:      /* Max connections for this guest exceeded */
855                 case 0x0e:      /* Max connections for target guest exceeded */
856                         err = -EAGAIN;
857                         break;
858                 case 0x0f:      /* Missing IUCV authorization */
859                         err = -EACCES;
860                         break;
861                 default:
862                         err = -ECONNREFUSED;
863                         break;
864                 }
865         }
866 done:
867         return err;
868 }
869
870 /* Connect an unconnected socket */
871 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
872                              int alen, int flags)
873 {
874         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
875         struct sock *sk = sock->sk;
876         struct iucv_sock *iucv = iucv_sk(sk);
877         int err;
878
879         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
880                 return -EINVAL;
881
882         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
883                 return -EBADFD;
884
885         if (sk->sk_state == IUCV_OPEN &&
886             iucv->transport == AF_IUCV_TRANS_HIPER)
887                 return -EBADFD; /* explicit bind required */
888
889         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
890                 return -EINVAL;
891
892         if (sk->sk_state == IUCV_OPEN) {
893                 err = iucv_sock_autobind(sk);
894                 if (unlikely(err))
895                         return err;
896         }
897
898         lock_sock(sk);
899
900         /* Set the destination information */
901         memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
902         memcpy(iucv->dst_name, sa->siucv_name, 8);
903
904         if (iucv->transport == AF_IUCV_TRANS_HIPER)
905                 err = afiucv_hs_connect(sock);
906         else
907                 err = afiucv_path_connect(sock, addr);
908         if (err)
909                 goto done;
910
911         if (sk->sk_state != IUCV_CONNECTED)
912                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
913                                                             IUCV_DISCONN),
914                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
915
916         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
917                 err = -ECONNREFUSED;
918
919         if (err && iucv->transport == AF_IUCV_TRANS_IUCV) {
920                 pr_iucv->path_sever(iucv->path, NULL);
921                 iucv_path_free(iucv->path);
922                 iucv->path = NULL;
923         }
924
925 done:
926         release_sock(sk);
927         return err;
928 }
929
930 /* Move a socket into listening state. */
931 static int iucv_sock_listen(struct socket *sock, int backlog)
932 {
933         struct sock *sk = sock->sk;
934         int err;
935
936         lock_sock(sk);
937
938         err = -EINVAL;
939         if (sk->sk_state != IUCV_BOUND)
940                 goto done;
941
942         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
943                 goto done;
944
945         sk->sk_max_ack_backlog = backlog;
946         sk->sk_ack_backlog = 0;
947         sk->sk_state = IUCV_LISTEN;
948         err = 0;
949
950 done:
951         release_sock(sk);
952         return err;
953 }
954
955 /* Accept a pending connection */
956 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
957                             int flags)
958 {
959         DECLARE_WAITQUEUE(wait, current);
960         struct sock *sk = sock->sk, *nsk;
961         long timeo;
962         int err = 0;
963
964         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
965
966         if (sk->sk_state != IUCV_LISTEN) {
967                 err = -EBADFD;
968                 goto done;
969         }
970
971         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
972
973         /* Wait for an incoming connection */
974         add_wait_queue_exclusive(sk_sleep(sk), &wait);
975         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
976                 set_current_state(TASK_INTERRUPTIBLE);
977                 if (!timeo) {
978                         err = -EAGAIN;
979                         break;
980                 }
981
982                 release_sock(sk);
983                 timeo = schedule_timeout(timeo);
984                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
985
986                 if (sk->sk_state != IUCV_LISTEN) {
987                         err = -EBADFD;
988                         break;
989                 }
990
991                 if (signal_pending(current)) {
992                         err = sock_intr_errno(timeo);
993                         break;
994                 }
995         }
996
997         set_current_state(TASK_RUNNING);
998         remove_wait_queue(sk_sleep(sk), &wait);
999
1000         if (err)
1001                 goto done;
1002
1003         newsock->state = SS_CONNECTED;
1004
1005 done:
1006         release_sock(sk);
1007         return err;
1008 }
1009
1010 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
1011                              int *len, int peer)
1012 {
1013         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
1014         struct sock *sk = sock->sk;
1015         struct iucv_sock *iucv = iucv_sk(sk);
1016
1017         addr->sa_family = AF_IUCV;
1018         *len = sizeof(struct sockaddr_iucv);
1019
1020         if (peer) {
1021                 memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
1022                 memcpy(siucv->siucv_name, iucv->dst_name, 8);
1023         } else {
1024                 memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
1025                 memcpy(siucv->siucv_name, iucv->src_name, 8);
1026         }
1027         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
1028         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
1029         memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
1030
1031         return 0;
1032 }
1033
1034 /**
1035  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1036  * @path:       IUCV path
1037  * @msg:        Pointer to a struct iucv_message
1038  * @skb:        The socket data to send, skb->len MUST BE <= 7
1039  *
1040  * Send the socket data in the parameter list in the iucv message
1041  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1042  * list and the socket data len at index 7 (last byte).
1043  * See also iucv_msg_length().
1044  *
1045  * Returns the error code from the iucv_message_send() call.
1046  */
1047 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1048                           struct sk_buff *skb)
1049 {
1050         u8 prmdata[8];
1051
1052         memcpy(prmdata, (void *) skb->data, skb->len);
1053         prmdata[7] = 0xff - (u8) skb->len;
1054         return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1055                                  (void *) prmdata, 8);
1056 }
1057
1058 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
1059                              struct msghdr *msg, size_t len)
1060 {
1061         struct sock *sk = sock->sk;
1062         struct iucv_sock *iucv = iucv_sk(sk);
1063         struct sk_buff *skb;
1064         struct iucv_message txmsg;
1065         struct cmsghdr *cmsg;
1066         int cmsg_done;
1067         long timeo;
1068         char user_id[9];
1069         char appl_id[9];
1070         int err;
1071         int noblock = msg->msg_flags & MSG_DONTWAIT;
1072
1073         err = sock_error(sk);
1074         if (err)
1075                 return err;
1076
1077         if (msg->msg_flags & MSG_OOB)
1078                 return -EOPNOTSUPP;
1079
1080         /* SOCK_SEQPACKET: we do not support segmented records */
1081         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1082                 return -EOPNOTSUPP;
1083
1084         lock_sock(sk);
1085
1086         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1087                 err = -EPIPE;
1088                 goto out;
1089         }
1090
1091         /* Return if the socket is not in connected state */
1092         if (sk->sk_state != IUCV_CONNECTED) {
1093                 err = -ENOTCONN;
1094                 goto out;
1095         }
1096
1097         /* initialize defaults */
1098         cmsg_done   = 0;        /* check for duplicate headers */
1099         txmsg.class = 0;
1100
1101         /* iterate over control messages */
1102         for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
1103                 cmsg = CMSG_NXTHDR(msg, cmsg)) {
1104
1105                 if (!CMSG_OK(msg, cmsg)) {
1106                         err = -EINVAL;
1107                         goto out;
1108                 }
1109
1110                 if (cmsg->cmsg_level != SOL_IUCV)
1111                         continue;
1112
1113                 if (cmsg->cmsg_type & cmsg_done) {
1114                         err = -EINVAL;
1115                         goto out;
1116                 }
1117                 cmsg_done |= cmsg->cmsg_type;
1118
1119                 switch (cmsg->cmsg_type) {
1120                 case SCM_IUCV_TRGCLS:
1121                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1122                                 err = -EINVAL;
1123                                 goto out;
1124                         }
1125
1126                         /* set iucv message target class */
1127                         memcpy(&txmsg.class,
1128                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1129
1130                         break;
1131
1132                 default:
1133                         err = -EINVAL;
1134                         goto out;
1135                         break;
1136                 }
1137         }
1138
1139         /* allocate one skb for each iucv message:
1140          * this is fine for SOCK_SEQPACKET (unless we want to support
1141          * segmented records using the MSG_EOR flag), but
1142          * for SOCK_STREAM we might want to improve it in future */
1143         if (iucv->transport == AF_IUCV_TRANS_HIPER)
1144                 skb = sock_alloc_send_skb(sk,
1145                         len + sizeof(struct af_iucv_trans_hdr) + ETH_HLEN,
1146                         noblock, &err);
1147         else
1148                 skb = sock_alloc_send_skb(sk, len, noblock, &err);
1149         if (!skb)
1150                 goto out;
1151         if (iucv->transport == AF_IUCV_TRANS_HIPER)
1152                 skb_reserve(skb, sizeof(struct af_iucv_trans_hdr) + ETH_HLEN);
1153         if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
1154                 err = -EFAULT;
1155                 goto fail;
1156         }
1157
1158         /* wait if outstanding messages for iucv path has reached */
1159         timeo = sock_sndtimeo(sk, noblock);
1160         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1161         if (err)
1162                 goto fail;
1163
1164         /* return -ECONNRESET if the socket is no longer connected */
1165         if (sk->sk_state != IUCV_CONNECTED) {
1166                 err = -ECONNRESET;
1167                 goto fail;
1168         }
1169
1170         /* increment and save iucv message tag for msg_completion cbk */
1171         txmsg.tag = iucv->send_tag++;
1172         memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);
1173         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1174                 atomic_inc(&iucv->msg_sent);
1175                 err = afiucv_hs_send(&txmsg, sk, skb, 0);
1176                 if (err) {
1177                         atomic_dec(&iucv->msg_sent);
1178                         goto fail;
1179                 }
1180                 goto release;
1181         }
1182         skb_queue_tail(&iucv->send_skb_q, skb);
1183
1184         if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
1185               && skb->len <= 7) {
1186                 err = iucv_send_iprm(iucv->path, &txmsg, skb);
1187
1188                 /* on success: there is no message_complete callback
1189                  * for an IPRMDATA msg; remove skb from send queue */
1190                 if (err == 0) {
1191                         skb_unlink(skb, &iucv->send_skb_q);
1192                         kfree_skb(skb);
1193                 }
1194
1195                 /* this error should never happen since the
1196                  * IUCV_IPRMDATA path flag is set... sever path */
1197                 if (err == 0x15) {
1198                         pr_iucv->path_sever(iucv->path, NULL);
1199                         skb_unlink(skb, &iucv->send_skb_q);
1200                         err = -EPIPE;
1201                         goto fail;
1202                 }
1203         } else
1204                 err = pr_iucv->message_send(iucv->path, &txmsg, 0, 0,
1205                                         (void *) skb->data, skb->len);
1206         if (err) {
1207                 if (err == 3) {
1208                         user_id[8] = 0;
1209                         memcpy(user_id, iucv->dst_user_id, 8);
1210                         appl_id[8] = 0;
1211                         memcpy(appl_id, iucv->dst_name, 8);
1212                         pr_err("Application %s on z/VM guest %s"
1213                                 " exceeds message limit\n",
1214                                 appl_id, user_id);
1215                         err = -EAGAIN;
1216                 } else
1217                         err = -EPIPE;
1218                 skb_unlink(skb, &iucv->send_skb_q);
1219                 goto fail;
1220         }
1221
1222 release:
1223         release_sock(sk);
1224         return len;
1225
1226 fail:
1227         kfree_skb(skb);
1228 out:
1229         release_sock(sk);
1230         return err;
1231 }
1232
1233 /* iucv_fragment_skb() - Fragment a single IUCV message into multiple skb's
1234  *
1235  * Locking: must be called with message_q.lock held
1236  */
1237 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
1238 {
1239         int dataleft, size, copied = 0;
1240         struct sk_buff *nskb;
1241
1242         dataleft = len;
1243         while (dataleft) {
1244                 if (dataleft >= sk->sk_rcvbuf / 4)
1245                         size = sk->sk_rcvbuf / 4;
1246                 else
1247                         size = dataleft;
1248
1249                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
1250                 if (!nskb)
1251                         return -ENOMEM;
1252
1253                 /* copy target class to control buffer of new skb */
1254                 memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);
1255
1256                 /* copy data fragment */
1257                 memcpy(nskb->data, skb->data + copied, size);
1258                 copied += size;
1259                 dataleft -= size;
1260
1261                 skb_reset_transport_header(nskb);
1262                 skb_reset_network_header(nskb);
1263                 nskb->len = size;
1264
1265                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
1266         }
1267
1268         return 0;
1269 }
1270
1271 /* iucv_process_message() - Receive a single outstanding IUCV message
1272  *
1273  * Locking: must be called with message_q.lock held
1274  */
1275 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1276                                  struct iucv_path *path,
1277                                  struct iucv_message *msg)
1278 {
1279         int rc;
1280         unsigned int len;
1281
1282         len = iucv_msg_length(msg);
1283
1284         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1285         /* Note: the first 4 bytes are reserved for msg tag */
1286         memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);
1287
1288         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1289         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1290                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1291                         skb->data = NULL;
1292                         skb->len = 0;
1293                 }
1294         } else {
1295                 rc = pr_iucv->message_receive(path, msg,
1296                                               msg->flags & IUCV_IPRMDATA,
1297                                               skb->data, len, NULL);
1298                 if (rc) {
1299                         kfree_skb(skb);
1300                         return;
1301                 }
1302                 /* we need to fragment iucv messages for SOCK_STREAM only;
1303                  * for SOCK_SEQPACKET, it is only relevant if we support
1304                  * record segmentation using MSG_EOR (see also recvmsg()) */
1305                 if (sk->sk_type == SOCK_STREAM &&
1306                     skb->truesize >= sk->sk_rcvbuf / 4) {
1307                         rc = iucv_fragment_skb(sk, skb, len);
1308                         kfree_skb(skb);
1309                         skb = NULL;
1310                         if (rc) {
1311                                 pr_iucv->path_sever(path, NULL);
1312                                 return;
1313                         }
1314                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
1315                 } else {
1316                         skb_reset_transport_header(skb);
1317                         skb_reset_network_header(skb);
1318                         skb->len = len;
1319                 }
1320         }
1321
1322         if (sock_queue_rcv_skb(sk, skb))
1323                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1324 }
1325
1326 /* iucv_process_message_q() - Process outstanding IUCV messages
1327  *
1328  * Locking: must be called with message_q.lock held
1329  */
1330 static void iucv_process_message_q(struct sock *sk)
1331 {
1332         struct iucv_sock *iucv = iucv_sk(sk);
1333         struct sk_buff *skb;
1334         struct sock_msg_q *p, *n;
1335
1336         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1337                 skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1338                 if (!skb)
1339                         break;
1340                 iucv_process_message(sk, skb, p->path, &p->msg);
1341                 list_del(&p->list);
1342                 kfree(p);
1343                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1344                         break;
1345         }
1346 }
1347
1348 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1349                              struct msghdr *msg, size_t len, int flags)
1350 {
1351         int noblock = flags & MSG_DONTWAIT;
1352         struct sock *sk = sock->sk;
1353         struct iucv_sock *iucv = iucv_sk(sk);
1354         unsigned int copied, rlen;
1355         struct sk_buff *skb, *rskb, *cskb, *sskb;
1356         int blen;
1357         int err = 0;
1358
1359         if ((sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED) &&
1360             skb_queue_empty(&iucv->backlog_skb_q) &&
1361             skb_queue_empty(&sk->sk_receive_queue) &&
1362             list_empty(&iucv->message_q.list))
1363                 return 0;
1364
1365         if (flags & (MSG_OOB))
1366                 return -EOPNOTSUPP;
1367
1368         /* receive/dequeue next skb:
1369          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1370         skb = skb_recv_datagram(sk, flags, noblock, &err);
1371         if (!skb) {
1372                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1373                         return 0;
1374                 return err;
1375         }
1376
1377         rlen   = skb->len;              /* real length of skb */
1378         copied = min_t(unsigned int, rlen, len);
1379
1380         cskb = skb;
1381         if (skb_copy_datagram_iovec(cskb, 0, msg->msg_iov, copied)) {
1382                 if (!(flags & MSG_PEEK))
1383                         skb_queue_head(&sk->sk_receive_queue, skb);
1384                 return -EFAULT;
1385         }
1386
1387         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1388         if (sk->sk_type == SOCK_SEQPACKET) {
1389                 if (copied < rlen)
1390                         msg->msg_flags |= MSG_TRUNC;
1391                 /* each iucv message contains a complete record */
1392                 msg->msg_flags |= MSG_EOR;
1393         }
1394
1395         /* create control message to store iucv msg target class:
1396          * get the trgcls from the control buffer of the skb due to
1397          * fragmentation of original iucv message. */
1398         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1399                         CB_TRGCLS_LEN, CB_TRGCLS(skb));
1400         if (err) {
1401                 if (!(flags & MSG_PEEK))
1402                         skb_queue_head(&sk->sk_receive_queue, skb);
1403                 return err;
1404         }
1405
1406         /* Mark read part of skb as used */
1407         if (!(flags & MSG_PEEK)) {
1408
1409                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1410                 if (sk->sk_type == SOCK_STREAM) {
1411                         skb_pull(skb, copied);
1412                         if (skb->len) {
1413                                 skb_queue_head(&sk->sk_receive_queue, skb);
1414                                 goto done;
1415                         }
1416                 }
1417
1418                 kfree_skb(skb);
1419                 atomic_inc(&iucv->msg_recv);
1420
1421                 /* Queue backlog skbs */
1422                 spin_lock_bh(&iucv->message_q.lock);
1423                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1424                 while (rskb) {
1425                         if (sock_queue_rcv_skb(sk, rskb)) {
1426                                 skb_queue_head(&iucv->backlog_skb_q,
1427                                                 rskb);
1428                                 break;
1429                         } else {
1430                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1431                         }
1432                 }
1433                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1434                         if (!list_empty(&iucv->message_q.list))
1435                                 iucv_process_message_q(sk);
1436                         if (atomic_read(&iucv->msg_recv) >=
1437                                                         iucv->msglimit / 2) {
1438                                 /* send WIN to peer */
1439                                 blen = sizeof(struct af_iucv_trans_hdr) +
1440                                         ETH_HLEN;
1441                                 sskb = sock_alloc_send_skb(sk, blen, 1, &err);
1442                                 if (sskb) {
1443                                         skb_reserve(sskb,
1444                                                 sizeof(struct af_iucv_trans_hdr)
1445                                                 + ETH_HLEN);
1446                                         err = afiucv_hs_send(NULL, sk, sskb,
1447                                                              AF_IUCV_FLAG_WIN);
1448                                 }
1449                                 if (err) {
1450                                         sk->sk_state = IUCV_DISCONN;
1451                                         sk->sk_state_change(sk);
1452                                 }
1453                         }
1454                 }
1455                 spin_unlock_bh(&iucv->message_q.lock);
1456         }
1457
1458 done:
1459         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1460         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1461                 copied = rlen;
1462
1463         return copied;
1464 }
1465
1466 static inline unsigned int iucv_accept_poll(struct sock *parent)
1467 {
1468         struct iucv_sock *isk, *n;
1469         struct sock *sk;
1470
1471         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1472                 sk = (struct sock *) isk;
1473
1474                 if (sk->sk_state == IUCV_CONNECTED)
1475                         return POLLIN | POLLRDNORM;
1476         }
1477
1478         return 0;
1479 }
1480
1481 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1482                             poll_table *wait)
1483 {
1484         struct sock *sk = sock->sk;
1485         unsigned int mask = 0;
1486
1487         sock_poll_wait(file, sk_sleep(sk), wait);
1488
1489         if (sk->sk_state == IUCV_LISTEN)
1490                 return iucv_accept_poll(sk);
1491
1492         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1493                 mask |= POLLERR;
1494
1495         if (sk->sk_shutdown & RCV_SHUTDOWN)
1496                 mask |= POLLRDHUP;
1497
1498         if (sk->sk_shutdown == SHUTDOWN_MASK)
1499                 mask |= POLLHUP;
1500
1501         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1502             (sk->sk_shutdown & RCV_SHUTDOWN))
1503                 mask |= POLLIN | POLLRDNORM;
1504
1505         if (sk->sk_state == IUCV_CLOSED)
1506                 mask |= POLLHUP;
1507
1508         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_SEVERED)
1509                 mask |= POLLIN;
1510
1511         if (sock_writeable(sk))
1512                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1513         else
1514                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1515
1516         return mask;
1517 }
1518
1519 static int iucv_sock_shutdown(struct socket *sock, int how)
1520 {
1521         struct sock *sk = sock->sk;
1522         struct iucv_sock *iucv = iucv_sk(sk);
1523         struct iucv_message txmsg;
1524         int err = 0;
1525
1526         how++;
1527
1528         if ((how & ~SHUTDOWN_MASK) || !how)
1529                 return -EINVAL;
1530
1531         lock_sock(sk);
1532         switch (sk->sk_state) {
1533         case IUCV_DISCONN:
1534         case IUCV_CLOSING:
1535         case IUCV_SEVERED:
1536         case IUCV_CLOSED:
1537                 err = -ENOTCONN;
1538                 goto fail;
1539
1540         default:
1541                 sk->sk_shutdown |= how;
1542                 break;
1543         }
1544
1545         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1546                 txmsg.class = 0;
1547                 txmsg.tag = 0;
1548                 err = pr_iucv->message_send(iucv->path, &txmsg, IUCV_IPRMDATA,
1549                                         0, (void *) iprm_shutdown, 8);
1550                 if (err) {
1551                         switch (err) {
1552                         case 1:
1553                                 err = -ENOTCONN;
1554                                 break;
1555                         case 2:
1556                                 err = -ECONNRESET;
1557                                 break;
1558                         default:
1559                                 err = -ENOTCONN;
1560                                 break;
1561                         }
1562                 }
1563         }
1564
1565         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1566                 err = pr_iucv->path_quiesce(iucv->path, NULL);
1567                 if (err)
1568                         err = -ENOTCONN;
1569
1570                 skb_queue_purge(&sk->sk_receive_queue);
1571         }
1572
1573         /* Wake up anyone sleeping in poll */
1574         sk->sk_state_change(sk);
1575
1576 fail:
1577         release_sock(sk);
1578         return err;
1579 }
1580
1581 static int iucv_sock_release(struct socket *sock)
1582 {
1583         struct sock *sk = sock->sk;
1584         int err = 0;
1585
1586         if (!sk)
1587                 return 0;
1588
1589         iucv_sock_close(sk);
1590
1591         /* Unregister with IUCV base support */
1592         if (iucv_sk(sk)->path) {
1593                 pr_iucv->path_sever(iucv_sk(sk)->path, NULL);
1594                 iucv_path_free(iucv_sk(sk)->path);
1595                 iucv_sk(sk)->path = NULL;
1596         }
1597
1598         sock_orphan(sk);
1599         iucv_sock_kill(sk);
1600         return err;
1601 }
1602
1603 /* getsockopt and setsockopt */
1604 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1605                                 char __user *optval, unsigned int optlen)
1606 {
1607         struct sock *sk = sock->sk;
1608         struct iucv_sock *iucv = iucv_sk(sk);
1609         int val;
1610         int rc;
1611
1612         if (level != SOL_IUCV)
1613                 return -ENOPROTOOPT;
1614
1615         if (optlen < sizeof(int))
1616                 return -EINVAL;
1617
1618         if (get_user(val, (int __user *) optval))
1619                 return -EFAULT;
1620
1621         rc = 0;
1622
1623         lock_sock(sk);
1624         switch (optname) {
1625         case SO_IPRMDATA_MSG:
1626                 if (val)
1627                         iucv->flags |= IUCV_IPRMDATA;
1628                 else
1629                         iucv->flags &= ~IUCV_IPRMDATA;
1630                 break;
1631         case SO_MSGLIMIT:
1632                 switch (sk->sk_state) {
1633                 case IUCV_OPEN:
1634                 case IUCV_BOUND:
1635                         if (val < 1 || val > (u16)(~0))
1636                                 rc = -EINVAL;
1637                         else
1638                                 iucv->msglimit = val;
1639                         break;
1640                 default:
1641                         rc = -EINVAL;
1642                         break;
1643                 }
1644                 break;
1645         default:
1646                 rc = -ENOPROTOOPT;
1647                 break;
1648         }
1649         release_sock(sk);
1650
1651         return rc;
1652 }
1653
1654 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1655                                 char __user *optval, int __user *optlen)
1656 {
1657         struct sock *sk = sock->sk;
1658         struct iucv_sock *iucv = iucv_sk(sk);
1659         int val, len;
1660
1661         if (level != SOL_IUCV)
1662                 return -ENOPROTOOPT;
1663
1664         if (get_user(len, optlen))
1665                 return -EFAULT;
1666
1667         if (len < 0)
1668                 return -EINVAL;
1669
1670         len = min_t(unsigned int, len, sizeof(int));
1671
1672         switch (optname) {
1673         case SO_IPRMDATA_MSG:
1674                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1675                 break;
1676         case SO_MSGLIMIT:
1677                 lock_sock(sk);
1678                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1679                                            : iucv->msglimit;    /* default */
1680                 release_sock(sk);
1681                 break;
1682         default:
1683                 return -ENOPROTOOPT;
1684         }
1685
1686         if (put_user(len, optlen))
1687                 return -EFAULT;
1688         if (copy_to_user(optval, &val, len))
1689                 return -EFAULT;
1690
1691         return 0;
1692 }
1693
1694
1695 /* Callback wrappers - called from iucv base support */
1696 static int iucv_callback_connreq(struct iucv_path *path,
1697                                  u8 ipvmid[8], u8 ipuser[16])
1698 {
1699         unsigned char user_data[16];
1700         unsigned char nuser_data[16];
1701         unsigned char src_name[8];
1702         struct hlist_node *node;
1703         struct sock *sk, *nsk;
1704         struct iucv_sock *iucv, *niucv;
1705         int err;
1706
1707         memcpy(src_name, ipuser, 8);
1708         EBCASC(src_name, 8);
1709         /* Find out if this path belongs to af_iucv. */
1710         read_lock(&iucv_sk_list.lock);
1711         iucv = NULL;
1712         sk = NULL;
1713         sk_for_each(sk, node, &iucv_sk_list.head)
1714                 if (sk->sk_state == IUCV_LISTEN &&
1715                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1716                         /*
1717                          * Found a listening socket with
1718                          * src_name == ipuser[0-7].
1719                          */
1720                         iucv = iucv_sk(sk);
1721                         break;
1722                 }
1723         read_unlock(&iucv_sk_list.lock);
1724         if (!iucv)
1725                 /* No socket found, not one of our paths. */
1726                 return -EINVAL;
1727
1728         bh_lock_sock(sk);
1729
1730         /* Check if parent socket is listening */
1731         low_nmcpy(user_data, iucv->src_name);
1732         high_nmcpy(user_data, iucv->dst_name);
1733         ASCEBC(user_data, sizeof(user_data));
1734         if (sk->sk_state != IUCV_LISTEN) {
1735                 err = pr_iucv->path_sever(path, user_data);
1736                 iucv_path_free(path);
1737                 goto fail;
1738         }
1739
1740         /* Check for backlog size */
1741         if (sk_acceptq_is_full(sk)) {
1742                 err = pr_iucv->path_sever(path, user_data);
1743                 iucv_path_free(path);
1744                 goto fail;
1745         }
1746
1747         /* Create the new socket */
1748         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1749         if (!nsk) {
1750                 err = pr_iucv->path_sever(path, user_data);
1751                 iucv_path_free(path);
1752                 goto fail;
1753         }
1754
1755         niucv = iucv_sk(nsk);
1756         iucv_sock_init(nsk, sk);
1757
1758         /* Set the new iucv_sock */
1759         memcpy(niucv->dst_name, ipuser + 8, 8);
1760         EBCASC(niucv->dst_name, 8);
1761         memcpy(niucv->dst_user_id, ipvmid, 8);
1762         memcpy(niucv->src_name, iucv->src_name, 8);
1763         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1764         niucv->path = path;
1765
1766         /* Call iucv_accept */
1767         high_nmcpy(nuser_data, ipuser + 8);
1768         memcpy(nuser_data + 8, niucv->src_name, 8);
1769         ASCEBC(nuser_data + 8, 8);
1770
1771         /* set message limit for path based on msglimit of accepting socket */
1772         niucv->msglimit = iucv->msglimit;
1773         path->msglim = iucv->msglimit;
1774         err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1775         if (err) {
1776                 err = pr_iucv->path_sever(path, user_data);
1777                 iucv_path_free(path);
1778                 iucv_sock_kill(nsk);
1779                 goto fail;
1780         }
1781
1782         iucv_accept_enqueue(sk, nsk);
1783
1784         /* Wake up accept */
1785         nsk->sk_state = IUCV_CONNECTED;
1786         sk->sk_data_ready(sk, 1);
1787         err = 0;
1788 fail:
1789         bh_unlock_sock(sk);
1790         return 0;
1791 }
1792
1793 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1794 {
1795         struct sock *sk = path->private;
1796
1797         sk->sk_state = IUCV_CONNECTED;
1798         sk->sk_state_change(sk);
1799 }
1800
1801 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1802 {
1803         struct sock *sk = path->private;
1804         struct iucv_sock *iucv = iucv_sk(sk);
1805         struct sk_buff *skb;
1806         struct sock_msg_q *save_msg;
1807         int len;
1808
1809         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1810                 pr_iucv->message_reject(path, msg);
1811                 return;
1812         }
1813
1814         spin_lock(&iucv->message_q.lock);
1815
1816         if (!list_empty(&iucv->message_q.list) ||
1817             !skb_queue_empty(&iucv->backlog_skb_q))
1818                 goto save_message;
1819
1820         len = atomic_read(&sk->sk_rmem_alloc);
1821         len += SKB_TRUESIZE(iucv_msg_length(msg));
1822         if (len > sk->sk_rcvbuf)
1823                 goto save_message;
1824
1825         skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1826         if (!skb)
1827                 goto save_message;
1828
1829         iucv_process_message(sk, skb, path, msg);
1830         goto out_unlock;
1831
1832 save_message:
1833         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1834         if (!save_msg)
1835                 goto out_unlock;
1836         save_msg->path = path;
1837         save_msg->msg = *msg;
1838
1839         list_add_tail(&save_msg->list, &iucv->message_q.list);
1840
1841 out_unlock:
1842         spin_unlock(&iucv->message_q.lock);
1843 }
1844
1845 static void iucv_callback_txdone(struct iucv_path *path,
1846                                  struct iucv_message *msg)
1847 {
1848         struct sock *sk = path->private;
1849         struct sk_buff *this = NULL;
1850         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1851         struct sk_buff *list_skb = list->next;
1852         unsigned long flags;
1853
1854         if (!skb_queue_empty(list)) {
1855                 spin_lock_irqsave(&list->lock, flags);
1856
1857                 while (list_skb != (struct sk_buff *)list) {
1858                         if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {
1859                                 this = list_skb;
1860                                 break;
1861                         }
1862                         list_skb = list_skb->next;
1863                 }
1864                 if (this)
1865                         __skb_unlink(this, list);
1866
1867                 spin_unlock_irqrestore(&list->lock, flags);
1868
1869                 if (this) {
1870                         kfree_skb(this);
1871                         /* wake up any process waiting for sending */
1872                         iucv_sock_wake_msglim(sk);
1873                 }
1874         }
1875         BUG_ON(!this);
1876
1877         if (sk->sk_state == IUCV_CLOSING) {
1878                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1879                         sk->sk_state = IUCV_CLOSED;
1880                         sk->sk_state_change(sk);
1881                 }
1882         }
1883
1884 }
1885
1886 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1887 {
1888         struct sock *sk = path->private;
1889
1890         if (!list_empty(&iucv_sk(sk)->accept_q))
1891                 sk->sk_state = IUCV_SEVERED;
1892         else
1893                 sk->sk_state = IUCV_DISCONN;
1894
1895         sk->sk_state_change(sk);
1896 }
1897
1898 /* called if the other communication side shuts down its RECV direction;
1899  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1900  */
1901 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1902 {
1903         struct sock *sk = path->private;
1904
1905         bh_lock_sock(sk);
1906         if (sk->sk_state != IUCV_CLOSED) {
1907                 sk->sk_shutdown |= SEND_SHUTDOWN;
1908                 sk->sk_state_change(sk);
1909         }
1910         bh_unlock_sock(sk);
1911 }
1912
1913 /***************** HiperSockets transport callbacks ********************/
1914 static void afiucv_swap_src_dest(struct sk_buff *skb)
1915 {
1916         struct af_iucv_trans_hdr *trans_hdr =
1917                                 (struct af_iucv_trans_hdr *)skb->data;
1918         char tmpID[8];
1919         char tmpName[8];
1920
1921         ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1922         ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1923         ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1924         ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1925         memcpy(tmpID, trans_hdr->srcUserID, 8);
1926         memcpy(tmpName, trans_hdr->srcAppName, 8);
1927         memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1928         memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1929         memcpy(trans_hdr->destUserID, tmpID, 8);
1930         memcpy(trans_hdr->destAppName, tmpName, 8);
1931         skb_push(skb, ETH_HLEN);
1932         memset(skb->data, 0, ETH_HLEN);
1933 }
1934
1935 /**
1936  * afiucv_hs_callback_syn - react on received SYN
1937  **/
1938 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1939 {
1940         struct sock *nsk;
1941         struct iucv_sock *iucv, *niucv;
1942         struct af_iucv_trans_hdr *trans_hdr;
1943         int err;
1944
1945         iucv = iucv_sk(sk);
1946         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
1947         if (!iucv) {
1948                 /* no sock - connection refused */
1949                 afiucv_swap_src_dest(skb);
1950                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1951                 err = dev_queue_xmit(skb);
1952                 goto out;
1953         }
1954
1955         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1956         bh_lock_sock(sk);
1957         if ((sk->sk_state != IUCV_LISTEN) ||
1958             sk_acceptq_is_full(sk) ||
1959             !nsk) {
1960                 /* error on server socket - connection refused */
1961                 if (nsk)
1962                         sk_free(nsk);
1963                 afiucv_swap_src_dest(skb);
1964                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1965                 err = dev_queue_xmit(skb);
1966                 bh_unlock_sock(sk);
1967                 goto out;
1968         }
1969
1970         niucv = iucv_sk(nsk);
1971         iucv_sock_init(nsk, sk);
1972         niucv->transport = AF_IUCV_TRANS_HIPER;
1973         niucv->msglimit = iucv->msglimit;
1974         if (!trans_hdr->window)
1975                 niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1976         else
1977                 niucv->msglimit_peer = trans_hdr->window;
1978         memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
1979         memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
1980         memcpy(niucv->src_name, iucv->src_name, 8);
1981         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1982         nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
1983         afiucv_swap_src_dest(skb);
1984         trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
1985         trans_hdr->window = niucv->msglimit;
1986         /* if receiver acks the xmit connection is established */
1987         err = dev_queue_xmit(skb);
1988         if (!err) {
1989                 iucv_accept_enqueue(sk, nsk);
1990                 nsk->sk_state = IUCV_CONNECTED;
1991                 sk->sk_data_ready(sk, 1);
1992         } else
1993                 iucv_sock_kill(nsk);
1994         bh_unlock_sock(sk);
1995
1996 out:
1997         return NET_RX_SUCCESS;
1998 }
1999
2000 /**
2001  * afiucv_hs_callback_synack() - react on received SYN-ACK
2002  **/
2003 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
2004 {
2005         struct iucv_sock *iucv = iucv_sk(sk);
2006         struct af_iucv_trans_hdr *trans_hdr =
2007                                         (struct af_iucv_trans_hdr *)skb->data;
2008
2009         if (!iucv)
2010                 goto out;
2011         if (sk->sk_state != IUCV_BOUND)
2012                 goto out;
2013         bh_lock_sock(sk);
2014         iucv->msglimit_peer = trans_hdr->window;
2015         sk->sk_state = IUCV_CONNECTED;
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_synfin() - react on received SYN_FIN
2025  **/
2026 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2027 {
2028         struct iucv_sock *iucv = iucv_sk(sk);
2029
2030         if (!iucv)
2031                 goto out;
2032         if (sk->sk_state != IUCV_BOUND)
2033                 goto out;
2034         bh_lock_sock(sk);
2035         sk->sk_state = IUCV_DISCONN;
2036         sk->sk_state_change(sk);
2037         bh_unlock_sock(sk);
2038 out:
2039         kfree_skb(skb);
2040         return NET_RX_SUCCESS;
2041 }
2042
2043 /**
2044  * afiucv_hs_callback_fin() - react on received FIN
2045  **/
2046 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2047 {
2048         struct iucv_sock *iucv = iucv_sk(sk);
2049
2050         /* other end of connection closed */
2051         if (iucv) {
2052                 bh_lock_sock(sk);
2053                 if (!list_empty(&iucv->accept_q))
2054                         sk->sk_state = IUCV_SEVERED;
2055                 else
2056                         sk->sk_state = IUCV_DISCONN;
2057                 sk->sk_state_change(sk);
2058                 bh_unlock_sock(sk);
2059         }
2060         kfree_skb(skb);
2061         return NET_RX_SUCCESS;
2062 }
2063
2064 /**
2065  * afiucv_hs_callback_win() - react on received WIN
2066  **/
2067 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2068 {
2069         struct iucv_sock *iucv = iucv_sk(sk);
2070         struct af_iucv_trans_hdr *trans_hdr =
2071                                         (struct af_iucv_trans_hdr *)skb->data;
2072
2073         if (!iucv)
2074                 return NET_RX_SUCCESS;
2075
2076         if (sk->sk_state != IUCV_CONNECTED)
2077                 return NET_RX_SUCCESS;
2078
2079         atomic_sub(trans_hdr->window, &iucv->msg_sent);
2080         iucv_sock_wake_msglim(sk);
2081         return NET_RX_SUCCESS;
2082 }
2083
2084 /**
2085  * afiucv_hs_callback_rx() - react on received data
2086  **/
2087 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2088 {
2089         struct iucv_sock *iucv = iucv_sk(sk);
2090
2091         if (!iucv) {
2092                 kfree_skb(skb);
2093                 return NET_RX_SUCCESS;
2094         }
2095
2096         if (sk->sk_state != IUCV_CONNECTED) {
2097                 kfree_skb(skb);
2098                 return NET_RX_SUCCESS;
2099         }
2100
2101                 /* write stuff from iucv_msg to skb cb */
2102         if (skb->len <= sizeof(struct af_iucv_trans_hdr)) {
2103                 kfree_skb(skb);
2104                 return NET_RX_SUCCESS;
2105         }
2106         skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2107         skb_reset_transport_header(skb);
2108         skb_reset_network_header(skb);
2109         spin_lock(&iucv->message_q.lock);
2110         if (skb_queue_empty(&iucv->backlog_skb_q)) {
2111                 if (sock_queue_rcv_skb(sk, skb)) {
2112                         /* handle rcv queue full */
2113                         skb_queue_tail(&iucv->backlog_skb_q, skb);
2114                 }
2115         } else
2116                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2117         spin_unlock(&iucv->message_q.lock);
2118         return NET_RX_SUCCESS;
2119 }
2120
2121 /**
2122  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2123  *                   transport
2124  *                   called from netif RX softirq
2125  **/
2126 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2127         struct packet_type *pt, struct net_device *orig_dev)
2128 {
2129         struct hlist_node *node;
2130         struct sock *sk;
2131         struct iucv_sock *iucv;
2132         struct af_iucv_trans_hdr *trans_hdr;
2133         char nullstring[8];
2134         int err = 0;
2135
2136         skb_pull(skb, ETH_HLEN);
2137         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
2138         EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2139         EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2140         EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2141         EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2142         memset(nullstring, 0, sizeof(nullstring));
2143         iucv = NULL;
2144         sk = NULL;
2145         read_lock(&iucv_sk_list.lock);
2146         sk_for_each(sk, node, &iucv_sk_list.head) {
2147                 if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2148                         if ((!memcmp(&iucv_sk(sk)->src_name,
2149                                      trans_hdr->destAppName, 8)) &&
2150                             (!memcmp(&iucv_sk(sk)->src_user_id,
2151                                      trans_hdr->destUserID, 8)) &&
2152                             (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2153                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2154                                      nullstring, 8))) {
2155                                 iucv = iucv_sk(sk);
2156                                 break;
2157                         }
2158                 } else {
2159                         if ((!memcmp(&iucv_sk(sk)->src_name,
2160                                      trans_hdr->destAppName, 8)) &&
2161                             (!memcmp(&iucv_sk(sk)->src_user_id,
2162                                      trans_hdr->destUserID, 8)) &&
2163                             (!memcmp(&iucv_sk(sk)->dst_name,
2164                                      trans_hdr->srcAppName, 8)) &&
2165                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2166                                      trans_hdr->srcUserID, 8))) {
2167                                 iucv = iucv_sk(sk);
2168                                 break;
2169                         }
2170                 }
2171         }
2172         read_unlock(&iucv_sk_list.lock);
2173         if (!iucv)
2174                 sk = NULL;
2175
2176         /* no sock
2177         how should we send with no sock
2178         1) send without sock no send rc checking?
2179         2) introduce default sock to handle this cases
2180
2181          SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2182          data -> send FIN
2183          SYN|ACK, SYN|FIN, FIN -> no action? */
2184
2185         switch (trans_hdr->flags) {
2186         case AF_IUCV_FLAG_SYN:
2187                 /* connect request */
2188                 err = afiucv_hs_callback_syn(sk, skb);
2189                 break;
2190         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2191                 /* connect request confirmed */
2192                 err = afiucv_hs_callback_synack(sk, skb);
2193                 break;
2194         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2195                 /* connect request refused */
2196                 err = afiucv_hs_callback_synfin(sk, skb);
2197                 break;
2198         case (AF_IUCV_FLAG_FIN):
2199                 /* close request */
2200                 err = afiucv_hs_callback_fin(sk, skb);
2201                 break;
2202         case (AF_IUCV_FLAG_WIN):
2203                 err = afiucv_hs_callback_win(sk, skb);
2204                 if (skb->len > sizeof(struct af_iucv_trans_hdr))
2205                         err = afiucv_hs_callback_rx(sk, skb);
2206                 else
2207                         kfree(skb);
2208                 break;
2209         case 0:
2210                 /* plain data frame */
2211                 err = afiucv_hs_callback_rx(sk, skb);
2212                 break;
2213         default:
2214                 ;
2215         }
2216
2217         return err;
2218 }
2219
2220 /**
2221  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2222  *                                 transport
2223  **/
2224 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2225                                         enum iucv_tx_notify n)
2226 {
2227         struct sock *isk = skb->sk;
2228         struct sock *sk = NULL;
2229         struct iucv_sock *iucv = NULL;
2230         struct sk_buff_head *list;
2231         struct sk_buff *list_skb;
2232         struct sk_buff *this = NULL;
2233         unsigned long flags;
2234         struct hlist_node *node;
2235
2236         read_lock(&iucv_sk_list.lock);
2237         sk_for_each(sk, node, &iucv_sk_list.head)
2238                 if (sk == isk) {
2239                         iucv = iucv_sk(sk);
2240                         break;
2241                 }
2242         read_unlock(&iucv_sk_list.lock);
2243
2244         if (!iucv)
2245                 return;
2246
2247         bh_lock_sock(sk);
2248         list = &iucv->send_skb_q;
2249         list_skb = list->next;
2250         if (skb_queue_empty(list))
2251                 goto out_unlock;
2252
2253         spin_lock_irqsave(&list->lock, flags);
2254         while (list_skb != (struct sk_buff *)list) {
2255                 if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2256                         this = list_skb;
2257                         switch (n) {
2258                         case TX_NOTIFY_OK:
2259                                 __skb_unlink(this, list);
2260                                 iucv_sock_wake_msglim(sk);
2261                                 kfree_skb(this);
2262                                 break;
2263                         case TX_NOTIFY_PENDING:
2264                                 atomic_inc(&iucv->pendings);
2265                                 break;
2266                         case TX_NOTIFY_DELAYED_OK:
2267                                 __skb_unlink(this, list);
2268                                 atomic_dec(&iucv->pendings);
2269                                 if (atomic_read(&iucv->pendings) <= 0)
2270                                         iucv_sock_wake_msglim(sk);
2271                                 kfree_skb(this);
2272                                 break;
2273                         case TX_NOTIFY_UNREACHABLE:
2274                         case TX_NOTIFY_DELAYED_UNREACHABLE:
2275                         case TX_NOTIFY_TPQFULL: /* not yet used */
2276                         case TX_NOTIFY_GENERALERROR:
2277                         case TX_NOTIFY_DELAYED_GENERALERROR:
2278                                 __skb_unlink(this, list);
2279                                 kfree_skb(this);
2280                                 if (!list_empty(&iucv->accept_q))
2281                                         sk->sk_state = IUCV_SEVERED;
2282                                 else
2283                                         sk->sk_state = IUCV_DISCONN;
2284                                 sk->sk_state_change(sk);
2285                                 break;
2286                         }
2287                         break;
2288                 }
2289                 list_skb = list_skb->next;
2290         }
2291         spin_unlock_irqrestore(&list->lock, flags);
2292
2293 out_unlock:
2294         bh_unlock_sock(sk);
2295 }
2296 static const struct proto_ops iucv_sock_ops = {
2297         .family         = PF_IUCV,
2298         .owner          = THIS_MODULE,
2299         .release        = iucv_sock_release,
2300         .bind           = iucv_sock_bind,
2301         .connect        = iucv_sock_connect,
2302         .listen         = iucv_sock_listen,
2303         .accept         = iucv_sock_accept,
2304         .getname        = iucv_sock_getname,
2305         .sendmsg        = iucv_sock_sendmsg,
2306         .recvmsg        = iucv_sock_recvmsg,
2307         .poll           = iucv_sock_poll,
2308         .ioctl          = sock_no_ioctl,
2309         .mmap           = sock_no_mmap,
2310         .socketpair     = sock_no_socketpair,
2311         .shutdown       = iucv_sock_shutdown,
2312         .setsockopt     = iucv_sock_setsockopt,
2313         .getsockopt     = iucv_sock_getsockopt,
2314 };
2315
2316 static const struct net_proto_family iucv_sock_family_ops = {
2317         .family = AF_IUCV,
2318         .owner  = THIS_MODULE,
2319         .create = iucv_sock_create,
2320 };
2321
2322 static struct packet_type iucv_packet_type = {
2323         .type = cpu_to_be16(ETH_P_AF_IUCV),
2324         .func = afiucv_hs_rcv,
2325 };
2326
2327 static int afiucv_iucv_init(void)
2328 {
2329         int err;
2330
2331         err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2332         if (err)
2333                 goto out;
2334         /* establish dummy device */
2335         af_iucv_driver.bus = pr_iucv->bus;
2336         err = driver_register(&af_iucv_driver);
2337         if (err)
2338                 goto out_iucv;
2339         af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2340         if (!af_iucv_dev) {
2341                 err = -ENOMEM;
2342                 goto out_driver;
2343         }
2344         dev_set_name(af_iucv_dev, "af_iucv");
2345         af_iucv_dev->bus = pr_iucv->bus;
2346         af_iucv_dev->parent = pr_iucv->root;
2347         af_iucv_dev->release = (void (*)(struct device *))kfree;
2348         af_iucv_dev->driver = &af_iucv_driver;
2349         err = device_register(af_iucv_dev);
2350         if (err)
2351                 goto out_driver;
2352         return 0;
2353
2354 out_driver:
2355         driver_unregister(&af_iucv_driver);
2356 out_iucv:
2357         pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2358 out:
2359         return err;
2360 }
2361
2362 static int __init afiucv_init(void)
2363 {
2364         int err;
2365
2366         if (MACHINE_IS_VM) {
2367                 cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2368                 if (unlikely(err)) {
2369                         WARN_ON(err);
2370                         err = -EPROTONOSUPPORT;
2371                         goto out;
2372                 }
2373
2374                 pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2375                 if (!pr_iucv) {
2376                         printk(KERN_WARNING "iucv_if lookup failed\n");
2377                         memset(&iucv_userid, 0, sizeof(iucv_userid));
2378                 }
2379         } else {
2380                 memset(&iucv_userid, 0, sizeof(iucv_userid));
2381                 pr_iucv = NULL;
2382         }
2383
2384         err = proto_register(&iucv_proto, 0);
2385         if (err)
2386                 goto out;
2387         err = sock_register(&iucv_sock_family_ops);
2388         if (err)
2389                 goto out_proto;
2390
2391         if (pr_iucv) {
2392                 err = afiucv_iucv_init();
2393                 if (err)
2394                         goto out_sock;
2395         }
2396         dev_add_pack(&iucv_packet_type);
2397         return 0;
2398
2399 out_sock:
2400         sock_unregister(PF_IUCV);
2401 out_proto:
2402         proto_unregister(&iucv_proto);
2403 out:
2404         if (pr_iucv)
2405                 symbol_put(iucv_if);
2406         return err;
2407 }
2408
2409 static void __exit afiucv_exit(void)
2410 {
2411         if (pr_iucv) {
2412                 device_unregister(af_iucv_dev);
2413                 driver_unregister(&af_iucv_driver);
2414                 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2415                 symbol_put(iucv_if);
2416         }
2417         dev_remove_pack(&iucv_packet_type);
2418         sock_unregister(PF_IUCV);
2419         proto_unregister(&iucv_proto);
2420 }
2421
2422 module_init(afiucv_init);
2423 module_exit(afiucv_exit);
2424
2425 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2426 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2427 MODULE_VERSION(VERSION);
2428 MODULE_LICENSE("GPL");
2429 MODULE_ALIAS_NETPROTO(PF_IUCV);
2430