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TOMOYO Linux Cross Reference
Linux/net/iucv/af_iucv.c

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  1 /*
  2  *  IUCV protocol stack for Linux on zSeries
  3  *
  4  *  Copyright IBM Corp. 2006, 2009
  5  *
  6  *  Author(s):  Jennifer Hunt <jenhunt@us.ibm.com>
  7  *              Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
  8  *  PM functions:
  9  *              Ursula Braun <ursula.braun@de.ibm.com>
 10  */
 11 
 12 #define KMSG_COMPONENT "af_iucv"
 13 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 14 
 15 #include <linux/module.h>
 16 #include <linux/types.h>
 17 #include <linux/list.h>
 18 #include <linux/errno.h>
 19 #include <linux/kernel.h>
 20 #include <linux/sched.h>
 21 #include <linux/slab.h>
 22 #include <linux/skbuff.h>
 23 #include <linux/init.h>
 24 #include <linux/poll.h>
 25 #include <net/sock.h>
 26 #include <asm/ebcdic.h>
 27 #include <asm/cpcmd.h>
 28 #include <linux/kmod.h>
 29 
 30 #include <net/iucv/af_iucv.h>
 31 
 32 #define VERSION "1.2"
 33 
 34 static char iucv_userid[80];
 35 
 36 static const struct proto_ops iucv_sock_ops;
 37 
 38 static struct proto iucv_proto = {
 39         .name           = "AF_IUCV",
 40         .owner          = THIS_MODULE,
 41         .obj_size       = sizeof(struct iucv_sock),
 42 };
 43 
 44 static struct iucv_interface *pr_iucv;
 45 
 46 /* special AF_IUCV IPRM messages */
 47 static const u8 iprm_shutdown[8] =
 48         {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01};
 49 
 50 #define TRGCLS_SIZE     (sizeof(((struct iucv_message *)0)->class))
 51 
 52 /* macros to set/get socket control buffer at correct offset */
 53 #define CB_TAG(skb)     ((skb)->cb)             /* iucv message tag */
 54 #define CB_TAG_LEN      (sizeof(((struct iucv_message *) 0)->tag))
 55 #define CB_TRGCLS(skb)  ((skb)->cb + CB_TAG_LEN) /* iucv msg target class */
 56 #define CB_TRGCLS_LEN   (TRGCLS_SIZE)
 57 
 58 #define __iucv_sock_wait(sk, condition, timeo, ret)                     \
 59 do {                                                                    \
 60         DEFINE_WAIT(__wait);                                            \
 61         long __timeo = timeo;                                           \
 62         ret = 0;                                                        \
 63         prepare_to_wait(sk_sleep(sk), &__wait, TASK_INTERRUPTIBLE);     \
 64         while (!(condition)) {                                          \
 65                 if (!__timeo) {                                         \
 66                         ret = -EAGAIN;                                  \
 67                         break;                                          \
 68                 }                                                       \
 69                 if (signal_pending(current)) {                          \
 70                         ret = sock_intr_errno(__timeo);                 \
 71                         break;                                          \
 72                 }                                                       \
 73                 release_sock(sk);                                       \
 74                 __timeo = schedule_timeout(__timeo);                    \
 75                 lock_sock(sk);                                          \
 76                 ret = sock_error(sk);                                   \
 77                 if (ret)                                                \
 78                         break;                                          \
 79         }                                                               \
 80         finish_wait(sk_sleep(sk), &__wait);                             \
 81 } while (0)
 82 
 83 #define iucv_sock_wait(sk, condition, timeo)                            \
 84 ({                                                                      \
 85         int __ret = 0;                                                  \
 86         if (!(condition))                                               \
 87                 __iucv_sock_wait(sk, condition, timeo, __ret);          \
 88         __ret;                                                          \
 89 })
 90 
 91 static void iucv_sock_kill(struct sock *sk);
 92 static void iucv_sock_close(struct sock *sk);
 93 static void iucv_sever_path(struct sock *, int);
 94 
 95 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
 96         struct packet_type *pt, struct net_device *orig_dev);
 97 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
 98                    struct sk_buff *skb, u8 flags);
 99 static void afiucv_hs_callback_txnotify(struct sk_buff *, enum iucv_tx_notify);
100 
101 /* Call Back functions */
102 static void iucv_callback_rx(struct iucv_path *, struct iucv_message *);
103 static void iucv_callback_txdone(struct iucv_path *, struct iucv_message *);
104 static void iucv_callback_connack(struct iucv_path *, u8 ipuser[16]);
105 static int iucv_callback_connreq(struct iucv_path *, u8 ipvmid[8],
106                                  u8 ipuser[16]);
107 static void iucv_callback_connrej(struct iucv_path *, u8 ipuser[16]);
108 static void iucv_callback_shutdown(struct iucv_path *, u8 ipuser[16]);
109 
110 static struct iucv_sock_list iucv_sk_list = {
111         .lock = __RW_LOCK_UNLOCKED(iucv_sk_list.lock),
112         .autobind_name = ATOMIC_INIT(0)
113 };
114 
115 static struct iucv_handler af_iucv_handler = {
116         .path_pending     = iucv_callback_connreq,
117         .path_complete    = iucv_callback_connack,
118         .path_severed     = iucv_callback_connrej,
119         .message_pending  = iucv_callback_rx,
120         .message_complete = iucv_callback_txdone,
121         .path_quiesced    = iucv_callback_shutdown,
122 };
123 
124 static inline void high_nmcpy(unsigned char *dst, char *src)
125 {
126        memcpy(dst, src, 8);
127 }
128 
129 static inline void low_nmcpy(unsigned char *dst, char *src)
130 {
131        memcpy(&dst[8], src, 8);
132 }
133 
134 static int afiucv_pm_prepare(struct device *dev)
135 {
136 #ifdef CONFIG_PM_DEBUG
137         printk(KERN_WARNING "afiucv_pm_prepare\n");
138 #endif
139         return 0;
140 }
141 
142 static void afiucv_pm_complete(struct device *dev)
143 {
144 #ifdef CONFIG_PM_DEBUG
145         printk(KERN_WARNING "afiucv_pm_complete\n");
146 #endif
147 }
148 
149 /**
150  * afiucv_pm_freeze() - Freeze PM callback
151  * @dev:        AFIUCV dummy device
152  *
153  * Sever all established IUCV communication pathes
154  */
155 static int afiucv_pm_freeze(struct device *dev)
156 {
157         struct iucv_sock *iucv;
158         struct sock *sk;
159         struct hlist_node *node;
160         int err = 0;
161 
162 #ifdef CONFIG_PM_DEBUG
163         printk(KERN_WARNING "afiucv_pm_freeze\n");
164 #endif
165         read_lock(&iucv_sk_list.lock);
166         sk_for_each(sk, node, &iucv_sk_list.head) {
167                 iucv = iucv_sk(sk);
168                 switch (sk->sk_state) {
169                 case IUCV_DISCONN:
170                 case IUCV_CLOSING:
171                 case IUCV_CONNECTED:
172                         iucv_sever_path(sk, 0);
173                         break;
174                 case IUCV_OPEN:
175                 case IUCV_BOUND:
176                 case IUCV_LISTEN:
177                 case IUCV_CLOSED:
178                 default:
179                         break;
180                 }
181                 skb_queue_purge(&iucv->send_skb_q);
182                 skb_queue_purge(&iucv->backlog_skb_q);
183         }
184         read_unlock(&iucv_sk_list.lock);
185         return err;
186 }
187 
188 /**
189  * afiucv_pm_restore_thaw() - Thaw and restore PM callback
190  * @dev:        AFIUCV dummy device
191  *
192  * socket clean up after freeze
193  */
194 static int afiucv_pm_restore_thaw(struct device *dev)
195 {
196         struct sock *sk;
197         struct hlist_node *node;
198 
199 #ifdef CONFIG_PM_DEBUG
200         printk(KERN_WARNING "afiucv_pm_restore_thaw\n");
201 #endif
202         read_lock(&iucv_sk_list.lock);
203         sk_for_each(sk, node, &iucv_sk_list.head) {
204                 switch (sk->sk_state) {
205                 case IUCV_CONNECTED:
206                         sk->sk_err = EPIPE;
207                         sk->sk_state = IUCV_DISCONN;
208                         sk->sk_state_change(sk);
209                         break;
210                 case IUCV_DISCONN:
211                 case IUCV_CLOSING:
212                 case IUCV_LISTEN:
213                 case IUCV_BOUND:
214                 case IUCV_OPEN:
215                 default:
216                         break;
217                 }
218         }
219         read_unlock(&iucv_sk_list.lock);
220         return 0;
221 }
222 
223 static const struct dev_pm_ops afiucv_pm_ops = {
224         .prepare = afiucv_pm_prepare,
225         .complete = afiucv_pm_complete,
226         .freeze = afiucv_pm_freeze,
227         .thaw = afiucv_pm_restore_thaw,
228         .restore = afiucv_pm_restore_thaw,
229 };
230 
231 static struct device_driver af_iucv_driver = {
232         .owner = THIS_MODULE,
233         .name = "afiucv",
234         .bus  = NULL,
235         .pm   = &afiucv_pm_ops,
236 };
237 
238 /* dummy device used as trigger for PM functions */
239 static struct device *af_iucv_dev;
240 
241 /**
242  * iucv_msg_length() - Returns the length of an iucv message.
243  * @msg:        Pointer to struct iucv_message, MUST NOT be NULL
244  *
245  * The function returns the length of the specified iucv message @msg of data
246  * stored in a buffer and of data stored in the parameter list (PRMDATA).
247  *
248  * For IUCV_IPRMDATA, AF_IUCV uses the following convention to transport socket
249  * data:
250  *      PRMDATA[0..6]   socket data (max 7 bytes);
251  *      PRMDATA[7]      socket data length value (len is 0xff - PRMDATA[7])
252  *
253  * The socket data length is computed by subtracting the socket data length
254  * value from 0xFF.
255  * If the socket data len is greater 7, then PRMDATA can be used for special
256  * notifications (see iucv_sock_shutdown); and further,
257  * if the socket data len is > 7, the function returns 8.
258  *
259  * Use this function to allocate socket buffers to store iucv message data.
260  */
261 static inline size_t iucv_msg_length(struct iucv_message *msg)
262 {
263         size_t datalen;
264 
265         if (msg->flags & IUCV_IPRMDATA) {
266                 datalen = 0xff - msg->rmmsg[7];
267                 return (datalen < 8) ? datalen : 8;
268         }
269         return msg->length;
270 }
271 
272 /**
273  * iucv_sock_in_state() - check for specific states
274  * @sk:         sock structure
275  * @state:      first iucv sk state
276  * @state:      second iucv sk state
277  *
278  * Returns true if the socket in either in the first or second state.
279  */
280 static int iucv_sock_in_state(struct sock *sk, int state, int state2)
281 {
282         return (sk->sk_state == state || sk->sk_state == state2);
283 }
284 
285 /**
286  * iucv_below_msglim() - function to check if messages can be sent
287  * @sk:         sock structure
288  *
289  * Returns true if the send queue length is lower than the message limit.
290  * Always returns true if the socket is not connected (no iucv path for
291  * checking the message limit).
292  */
293 static inline int iucv_below_msglim(struct sock *sk)
294 {
295         struct iucv_sock *iucv = iucv_sk(sk);
296 
297         if (sk->sk_state != IUCV_CONNECTED)
298                 return 1;
299         if (iucv->transport == AF_IUCV_TRANS_IUCV)
300                 return (skb_queue_len(&iucv->send_skb_q) < iucv->path->msglim);
301         else
302                 return ((atomic_read(&iucv->msg_sent) < iucv->msglimit_peer) &&
303                         (atomic_read(&iucv->pendings) <= 0));
304 }
305 
306 /**
307  * iucv_sock_wake_msglim() - Wake up thread waiting on msg limit
308  */
309 static void iucv_sock_wake_msglim(struct sock *sk)
310 {
311         struct socket_wq *wq;
312 
313         rcu_read_lock();
314         wq = rcu_dereference(sk->sk_wq);
315         if (wq_has_sleeper(wq))
316                 wake_up_interruptible_all(&wq->wait);
317         sk_wake_async(sk, SOCK_WAKE_SPACE, POLL_OUT);
318         rcu_read_unlock();
319 }
320 
321 /**
322  * afiucv_hs_send() - send a message through HiperSockets transport
323  */
324 static int afiucv_hs_send(struct iucv_message *imsg, struct sock *sock,
325                    struct sk_buff *skb, u8 flags)
326 {
327         struct iucv_sock *iucv = iucv_sk(sock);
328         struct af_iucv_trans_hdr *phs_hdr;
329         struct sk_buff *nskb;
330         int err, confirm_recv = 0;
331 
332         memset(skb->head, 0, ETH_HLEN);
333         phs_hdr = (struct af_iucv_trans_hdr *)skb_push(skb,
334                                         sizeof(struct af_iucv_trans_hdr));
335         skb_reset_mac_header(skb);
336         skb_reset_network_header(skb);
337         skb_push(skb, ETH_HLEN);
338         skb_reset_mac_header(skb);
339         memset(phs_hdr, 0, sizeof(struct af_iucv_trans_hdr));
340 
341         phs_hdr->magic = ETH_P_AF_IUCV;
342         phs_hdr->version = 1;
343         phs_hdr->flags = flags;
344         if (flags == AF_IUCV_FLAG_SYN)
345                 phs_hdr->window = iucv->msglimit;
346         else if ((flags == AF_IUCV_FLAG_WIN) || !flags) {
347                 confirm_recv = atomic_read(&iucv->msg_recv);
348                 phs_hdr->window = confirm_recv;
349                 if (confirm_recv)
350                         phs_hdr->flags = phs_hdr->flags | AF_IUCV_FLAG_WIN;
351         }
352         memcpy(phs_hdr->destUserID, iucv->dst_user_id, 8);
353         memcpy(phs_hdr->destAppName, iucv->dst_name, 8);
354         memcpy(phs_hdr->srcUserID, iucv->src_user_id, 8);
355         memcpy(phs_hdr->srcAppName, iucv->src_name, 8);
356         ASCEBC(phs_hdr->destUserID, sizeof(phs_hdr->destUserID));
357         ASCEBC(phs_hdr->destAppName, sizeof(phs_hdr->destAppName));
358         ASCEBC(phs_hdr->srcUserID, sizeof(phs_hdr->srcUserID));
359         ASCEBC(phs_hdr->srcAppName, sizeof(phs_hdr->srcAppName));
360         if (imsg)
361                 memcpy(&phs_hdr->iucv_hdr, imsg, sizeof(struct iucv_message));
362 
363         skb->dev = iucv->hs_dev;
364         if (!skb->dev)
365                 return -ENODEV;
366         if (!(skb->dev->flags & IFF_UP) || !netif_carrier_ok(skb->dev))
367                 return -ENETDOWN;
368         if (skb->len > skb->dev->mtu) {
369                 if (sock->sk_type == SOCK_SEQPACKET)
370                         return -EMSGSIZE;
371                 else
372                         skb_trim(skb, skb->dev->mtu);
373         }
374         skb->protocol = ETH_P_AF_IUCV;
375         nskb = skb_clone(skb, GFP_ATOMIC);
376         if (!nskb)
377                 return -ENOMEM;
378         skb_queue_tail(&iucv->send_skb_q, nskb);
379         err = dev_queue_xmit(skb);
380         if (net_xmit_eval(err)) {
381                 skb_unlink(nskb, &iucv->send_skb_q);
382                 kfree_skb(nskb);
383         } else {
384                 atomic_sub(confirm_recv, &iucv->msg_recv);
385                 WARN_ON(atomic_read(&iucv->msg_recv) < 0);
386         }
387         return net_xmit_eval(err);
388 }
389 
390 static struct sock *__iucv_get_sock_by_name(char *nm)
391 {
392         struct sock *sk;
393         struct hlist_node *node;
394 
395         sk_for_each(sk, node, &iucv_sk_list.head)
396                 if (!memcmp(&iucv_sk(sk)->src_name, nm, 8))
397                         return sk;
398 
399         return NULL;
400 }
401 
402 static void iucv_sock_destruct(struct sock *sk)
403 {
404         skb_queue_purge(&sk->sk_receive_queue);
405         skb_queue_purge(&sk->sk_error_queue);
406 
407         sk_mem_reclaim(sk);
408 
409         if (!sock_flag(sk, SOCK_DEAD)) {
410                 pr_err("Attempt to release alive iucv socket %p\n", sk);
411                 return;
412         }
413 
414         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
415         WARN_ON(atomic_read(&sk->sk_wmem_alloc));
416         WARN_ON(sk->sk_wmem_queued);
417         WARN_ON(sk->sk_forward_alloc);
418 }
419 
420 /* Cleanup Listen */
421 static void iucv_sock_cleanup_listen(struct sock *parent)
422 {
423         struct sock *sk;
424 
425         /* Close non-accepted connections */
426         while ((sk = iucv_accept_dequeue(parent, NULL))) {
427                 iucv_sock_close(sk);
428                 iucv_sock_kill(sk);
429         }
430 
431         parent->sk_state = IUCV_CLOSED;
432 }
433 
434 /* Kill socket (only if zapped and orphaned) */
435 static void iucv_sock_kill(struct sock *sk)
436 {
437         if (!sock_flag(sk, SOCK_ZAPPED) || sk->sk_socket)
438                 return;
439 
440         iucv_sock_unlink(&iucv_sk_list, sk);
441         sock_set_flag(sk, SOCK_DEAD);
442         sock_put(sk);
443 }
444 
445 /* Terminate an IUCV path */
446 static void iucv_sever_path(struct sock *sk, int with_user_data)
447 {
448         unsigned char user_data[16];
449         struct iucv_sock *iucv = iucv_sk(sk);
450         struct iucv_path *path = iucv->path;
451 
452         if (iucv->path) {
453                 iucv->path = NULL;
454                 if (with_user_data) {
455                         low_nmcpy(user_data, iucv->src_name);
456                         high_nmcpy(user_data, iucv->dst_name);
457                         ASCEBC(user_data, sizeof(user_data));
458                         pr_iucv->path_sever(path, user_data);
459                 } else
460                         pr_iucv->path_sever(path, NULL);
461                 iucv_path_free(path);
462         }
463 }
464 
465 /* Send FIN through an IUCV socket for HIPER transport */
466 static int iucv_send_ctrl(struct sock *sk, u8 flags)
467 {
468         int err = 0;
469         int blen;
470         struct sk_buff *skb;
471 
472         blen = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
473         skb = sock_alloc_send_skb(sk, blen, 1, &err);
474         if (skb) {
475                 skb_reserve(skb, blen);
476                 err = afiucv_hs_send(NULL, sk, skb, flags);
477         }
478         return err;
479 }
480 
481 /* Close an IUCV socket */
482 static void iucv_sock_close(struct sock *sk)
483 {
484         struct iucv_sock *iucv = iucv_sk(sk);
485         unsigned long timeo;
486         int err = 0;
487 
488         lock_sock(sk);
489 
490         switch (sk->sk_state) {
491         case IUCV_LISTEN:
492                 iucv_sock_cleanup_listen(sk);
493                 break;
494 
495         case IUCV_CONNECTED:
496                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
497                         err = iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
498                         sk->sk_state = IUCV_DISCONN;
499                         sk->sk_state_change(sk);
500                 }
501         case IUCV_DISCONN:   /* fall through */
502                 sk->sk_state = IUCV_CLOSING;
503                 sk->sk_state_change(sk);
504 
505                 if (!err && !skb_queue_empty(&iucv->send_skb_q)) {
506                         if (sock_flag(sk, SOCK_LINGER) && sk->sk_lingertime)
507                                 timeo = sk->sk_lingertime;
508                         else
509                                 timeo = IUCV_DISCONN_TIMEOUT;
510                         iucv_sock_wait(sk,
511                                         iucv_sock_in_state(sk, IUCV_CLOSED, 0),
512                                         timeo);
513                 }
514 
515         case IUCV_CLOSING:   /* fall through */
516                 sk->sk_state = IUCV_CLOSED;
517                 sk->sk_state_change(sk);
518 
519                 sk->sk_err = ECONNRESET;
520                 sk->sk_state_change(sk);
521 
522                 skb_queue_purge(&iucv->send_skb_q);
523                 skb_queue_purge(&iucv->backlog_skb_q);
524 
525         default:   /* fall through */
526                 iucv_sever_path(sk, 1);
527         }
528 
529         if (iucv->hs_dev) {
530                 dev_put(iucv->hs_dev);
531                 iucv->hs_dev = NULL;
532                 sk->sk_bound_dev_if = 0;
533         }
534 
535         /* mark socket for deletion by iucv_sock_kill() */
536         sock_set_flag(sk, SOCK_ZAPPED);
537 
538         release_sock(sk);
539 }
540 
541 static void iucv_sock_init(struct sock *sk, struct sock *parent)
542 {
543         if (parent)
544                 sk->sk_type = parent->sk_type;
545 }
546 
547 static struct sock *iucv_sock_alloc(struct socket *sock, int proto, gfp_t prio)
548 {
549         struct sock *sk;
550         struct iucv_sock *iucv;
551 
552         sk = sk_alloc(&init_net, PF_IUCV, prio, &iucv_proto);
553         if (!sk)
554                 return NULL;
555         iucv = iucv_sk(sk);
556 
557         sock_init_data(sock, sk);
558         INIT_LIST_HEAD(&iucv->accept_q);
559         spin_lock_init(&iucv->accept_q_lock);
560         skb_queue_head_init(&iucv->send_skb_q);
561         INIT_LIST_HEAD(&iucv->message_q.list);
562         spin_lock_init(&iucv->message_q.lock);
563         skb_queue_head_init(&iucv->backlog_skb_q);
564         iucv->send_tag = 0;
565         atomic_set(&iucv->pendings, 0);
566         iucv->flags = 0;
567         iucv->msglimit = 0;
568         atomic_set(&iucv->msg_sent, 0);
569         atomic_set(&iucv->msg_recv, 0);
570         iucv->path = NULL;
571         iucv->sk_txnotify = afiucv_hs_callback_txnotify;
572         memset(&iucv->src_user_id , 0, 32);
573         if (pr_iucv)
574                 iucv->transport = AF_IUCV_TRANS_IUCV;
575         else
576                 iucv->transport = AF_IUCV_TRANS_HIPER;
577 
578         sk->sk_destruct = iucv_sock_destruct;
579         sk->sk_sndtimeo = IUCV_CONN_TIMEOUT;
580         sk->sk_allocation = GFP_DMA;
581 
582         sock_reset_flag(sk, SOCK_ZAPPED);
583 
584         sk->sk_protocol = proto;
585         sk->sk_state    = IUCV_OPEN;
586 
587         iucv_sock_link(&iucv_sk_list, sk);
588         return sk;
589 }
590 
591 /* Create an IUCV socket */
592 static int iucv_sock_create(struct net *net, struct socket *sock, int protocol,
593                             int kern)
594 {
595         struct sock *sk;
596 
597         if (protocol && protocol != PF_IUCV)
598                 return -EPROTONOSUPPORT;
599 
600         sock->state = SS_UNCONNECTED;
601 
602         switch (sock->type) {
603         case SOCK_STREAM:
604                 sock->ops = &iucv_sock_ops;
605                 break;
606         case SOCK_SEQPACKET:
607                 /* currently, proto ops can handle both sk types */
608                 sock->ops = &iucv_sock_ops;
609                 break;
610         default:
611                 return -ESOCKTNOSUPPORT;
612         }
613 
614         sk = iucv_sock_alloc(sock, protocol, GFP_KERNEL);
615         if (!sk)
616                 return -ENOMEM;
617 
618         iucv_sock_init(sk, NULL);
619 
620         return 0;
621 }
622 
623 void iucv_sock_link(struct iucv_sock_list *l, struct sock *sk)
624 {
625         write_lock_bh(&l->lock);
626         sk_add_node(sk, &l->head);
627         write_unlock_bh(&l->lock);
628 }
629 
630 void iucv_sock_unlink(struct iucv_sock_list *l, struct sock *sk)
631 {
632         write_lock_bh(&l->lock);
633         sk_del_node_init(sk);
634         write_unlock_bh(&l->lock);
635 }
636 
637 void iucv_accept_enqueue(struct sock *parent, struct sock *sk)
638 {
639         unsigned long flags;
640         struct iucv_sock *par = iucv_sk(parent);
641 
642         sock_hold(sk);
643         spin_lock_irqsave(&par->accept_q_lock, flags);
644         list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
645         spin_unlock_irqrestore(&par->accept_q_lock, flags);
646         iucv_sk(sk)->parent = parent;
647         sk_acceptq_added(parent);
648 }
649 
650 void iucv_accept_unlink(struct sock *sk)
651 {
652         unsigned long flags;
653         struct iucv_sock *par = iucv_sk(iucv_sk(sk)->parent);
654 
655         spin_lock_irqsave(&par->accept_q_lock, flags);
656         list_del_init(&iucv_sk(sk)->accept_q);
657         spin_unlock_irqrestore(&par->accept_q_lock, flags);
658         sk_acceptq_removed(iucv_sk(sk)->parent);
659         iucv_sk(sk)->parent = NULL;
660         sock_put(sk);
661 }
662 
663 struct sock *iucv_accept_dequeue(struct sock *parent, struct socket *newsock)
664 {
665         struct iucv_sock *isk, *n;
666         struct sock *sk;
667 
668         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
669                 sk = (struct sock *) isk;
670                 lock_sock(sk);
671 
672                 if (sk->sk_state == IUCV_CLOSED) {
673                         iucv_accept_unlink(sk);
674                         release_sock(sk);
675                         continue;
676                 }
677 
678                 if (sk->sk_state == IUCV_CONNECTED ||
679                     sk->sk_state == IUCV_DISCONN ||
680                     !newsock) {
681                         iucv_accept_unlink(sk);
682                         if (newsock)
683                                 sock_graft(sk, newsock);
684 
685                         release_sock(sk);
686                         return sk;
687                 }
688 
689                 release_sock(sk);
690         }
691         return NULL;
692 }
693 
694 /* Bind an unbound socket */
695 static int iucv_sock_bind(struct socket *sock, struct sockaddr *addr,
696                           int addr_len)
697 {
698         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
699         struct sock *sk = sock->sk;
700         struct iucv_sock *iucv;
701         int err = 0;
702         struct net_device *dev;
703         char uid[9];
704 
705         /* Verify the input sockaddr */
706         if (!addr || addr->sa_family != AF_IUCV)
707                 return -EINVAL;
708 
709         lock_sock(sk);
710         if (sk->sk_state != IUCV_OPEN) {
711                 err = -EBADFD;
712                 goto done;
713         }
714 
715         write_lock_bh(&iucv_sk_list.lock);
716 
717         iucv = iucv_sk(sk);
718         if (__iucv_get_sock_by_name(sa->siucv_name)) {
719                 err = -EADDRINUSE;
720                 goto done_unlock;
721         }
722         if (iucv->path)
723                 goto done_unlock;
724 
725         /* Bind the socket */
726         if (pr_iucv)
727                 if (!memcmp(sa->siucv_user_id, iucv_userid, 8))
728                         goto vm_bind; /* VM IUCV transport */
729 
730         /* try hiper transport */
731         memcpy(uid, sa->siucv_user_id, sizeof(uid));
732         ASCEBC(uid, 8);
733         rcu_read_lock();
734         for_each_netdev_rcu(&init_net, dev) {
735                 if (!memcmp(dev->perm_addr, uid, 8)) {
736                         memcpy(iucv->src_name, sa->siucv_name, 8);
737                         memcpy(iucv->src_user_id, sa->siucv_user_id, 8);
738                         sk->sk_bound_dev_if = dev->ifindex;
739                         iucv->hs_dev = dev;
740                         dev_hold(dev);
741                         sk->sk_state = IUCV_BOUND;
742                         iucv->transport = AF_IUCV_TRANS_HIPER;
743                         if (!iucv->msglimit)
744                                 iucv->msglimit = IUCV_HIPER_MSGLIM_DEFAULT;
745                         rcu_read_unlock();
746                         goto done_unlock;
747                 }
748         }
749         rcu_read_unlock();
750 vm_bind:
751         if (pr_iucv) {
752                 /* use local userid for backward compat */
753                 memcpy(iucv->src_name, sa->siucv_name, 8);
754                 memcpy(iucv->src_user_id, iucv_userid, 8);
755                 sk->sk_state = IUCV_BOUND;
756                 iucv->transport = AF_IUCV_TRANS_IUCV;
757                 if (!iucv->msglimit)
758                         iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
759                 goto done_unlock;
760         }
761         /* found no dev to bind */
762         err = -ENODEV;
763 done_unlock:
764         /* Release the socket list lock */
765         write_unlock_bh(&iucv_sk_list.lock);
766 done:
767         release_sock(sk);
768         return err;
769 }
770 
771 /* Automatically bind an unbound socket */
772 static int iucv_sock_autobind(struct sock *sk)
773 {
774         struct iucv_sock *iucv = iucv_sk(sk);
775         char name[12];
776         int err = 0;
777 
778         if (unlikely(!pr_iucv))
779                 return -EPROTO;
780 
781         memcpy(iucv->src_user_id, iucv_userid, 8);
782 
783         write_lock_bh(&iucv_sk_list.lock);
784 
785         sprintf(name, "%08x", atomic_inc_return(&iucv_sk_list.autobind_name));
786         while (__iucv_get_sock_by_name(name)) {
787                 sprintf(name, "%08x",
788                         atomic_inc_return(&iucv_sk_list.autobind_name));
789         }
790 
791         write_unlock_bh(&iucv_sk_list.lock);
792 
793         memcpy(&iucv->src_name, name, 8);
794 
795         if (!iucv->msglimit)
796                 iucv->msglimit = IUCV_QUEUELEN_DEFAULT;
797 
798         return err;
799 }
800 
801 static int afiucv_path_connect(struct socket *sock, struct sockaddr *addr)
802 {
803         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
804         struct sock *sk = sock->sk;
805         struct iucv_sock *iucv = iucv_sk(sk);
806         unsigned char user_data[16];
807         int err;
808 
809         high_nmcpy(user_data, sa->siucv_name);
810         low_nmcpy(user_data, iucv->src_name);
811         ASCEBC(user_data, sizeof(user_data));
812 
813         /* Create path. */
814         iucv->path = iucv_path_alloc(iucv->msglimit,
815                                      IUCV_IPRMDATA, GFP_KERNEL);
816         if (!iucv->path) {
817                 err = -ENOMEM;
818                 goto done;
819         }
820         err = pr_iucv->path_connect(iucv->path, &af_iucv_handler,
821                                     sa->siucv_user_id, NULL, user_data,
822                                     sk);
823         if (err) {
824                 iucv_path_free(iucv->path);
825                 iucv->path = NULL;
826                 switch (err) {
827                 case 0x0b:      /* Target communicator is not logged on */
828                         err = -ENETUNREACH;
829                         break;
830                 case 0x0d:      /* Max connections for this guest exceeded */
831                 case 0x0e:      /* Max connections for target guest exceeded */
832                         err = -EAGAIN;
833                         break;
834                 case 0x0f:      /* Missing IUCV authorization */
835                         err = -EACCES;
836                         break;
837                 default:
838                         err = -ECONNREFUSED;
839                         break;
840                 }
841         }
842 done:
843         return err;
844 }
845 
846 /* Connect an unconnected socket */
847 static int iucv_sock_connect(struct socket *sock, struct sockaddr *addr,
848                              int alen, int flags)
849 {
850         struct sockaddr_iucv *sa = (struct sockaddr_iucv *) addr;
851         struct sock *sk = sock->sk;
852         struct iucv_sock *iucv = iucv_sk(sk);
853         int err;
854 
855         if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv))
856                 return -EINVAL;
857 
858         if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)
859                 return -EBADFD;
860 
861         if (sk->sk_state == IUCV_OPEN &&
862             iucv->transport == AF_IUCV_TRANS_HIPER)
863                 return -EBADFD; /* explicit bind required */
864 
865         if (sk->sk_type != SOCK_STREAM && sk->sk_type != SOCK_SEQPACKET)
866                 return -EINVAL;
867 
868         if (sk->sk_state == IUCV_OPEN) {
869                 err = iucv_sock_autobind(sk);
870                 if (unlikely(err))
871                         return err;
872         }
873 
874         lock_sock(sk);
875 
876         /* Set the destination information */
877         memcpy(iucv->dst_user_id, sa->siucv_user_id, 8);
878         memcpy(iucv->dst_name, sa->siucv_name, 8);
879 
880         if (iucv->transport == AF_IUCV_TRANS_HIPER)
881                 err = iucv_send_ctrl(sock->sk, AF_IUCV_FLAG_SYN);
882         else
883                 err = afiucv_path_connect(sock, addr);
884         if (err)
885                 goto done;
886 
887         if (sk->sk_state != IUCV_CONNECTED)
888                 err = iucv_sock_wait(sk, iucv_sock_in_state(sk, IUCV_CONNECTED,
889                                                             IUCV_DISCONN),
890                                      sock_sndtimeo(sk, flags & O_NONBLOCK));
891 
892         if (sk->sk_state == IUCV_DISCONN || sk->sk_state == IUCV_CLOSED)
893                 err = -ECONNREFUSED;
894 
895         if (err && iucv->transport == AF_IUCV_TRANS_IUCV)
896                 iucv_sever_path(sk, 0);
897 
898 done:
899         release_sock(sk);
900         return err;
901 }
902 
903 /* Move a socket into listening state. */
904 static int iucv_sock_listen(struct socket *sock, int backlog)
905 {
906         struct sock *sk = sock->sk;
907         int err;
908 
909         lock_sock(sk);
910 
911         err = -EINVAL;
912         if (sk->sk_state != IUCV_BOUND)
913                 goto done;
914 
915         if (sock->type != SOCK_STREAM && sock->type != SOCK_SEQPACKET)
916                 goto done;
917 
918         sk->sk_max_ack_backlog = backlog;
919         sk->sk_ack_backlog = 0;
920         sk->sk_state = IUCV_LISTEN;
921         err = 0;
922 
923 done:
924         release_sock(sk);
925         return err;
926 }
927 
928 /* Accept a pending connection */
929 static int iucv_sock_accept(struct socket *sock, struct socket *newsock,
930                             int flags)
931 {
932         DECLARE_WAITQUEUE(wait, current);
933         struct sock *sk = sock->sk, *nsk;
934         long timeo;
935         int err = 0;
936 
937         lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
938 
939         if (sk->sk_state != IUCV_LISTEN) {
940                 err = -EBADFD;
941                 goto done;
942         }
943 
944         timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
945 
946         /* Wait for an incoming connection */
947         add_wait_queue_exclusive(sk_sleep(sk), &wait);
948         while (!(nsk = iucv_accept_dequeue(sk, newsock))) {
949                 set_current_state(TASK_INTERRUPTIBLE);
950                 if (!timeo) {
951                         err = -EAGAIN;
952                         break;
953                 }
954 
955                 release_sock(sk);
956                 timeo = schedule_timeout(timeo);
957                 lock_sock_nested(sk, SINGLE_DEPTH_NESTING);
958 
959                 if (sk->sk_state != IUCV_LISTEN) {
960                         err = -EBADFD;
961                         break;
962                 }
963 
964                 if (signal_pending(current)) {
965                         err = sock_intr_errno(timeo);
966                         break;
967                 }
968         }
969 
970         set_current_state(TASK_RUNNING);
971         remove_wait_queue(sk_sleep(sk), &wait);
972 
973         if (err)
974                 goto done;
975 
976         newsock->state = SS_CONNECTED;
977 
978 done:
979         release_sock(sk);
980         return err;
981 }
982 
983 static int iucv_sock_getname(struct socket *sock, struct sockaddr *addr,
984                              int *len, int peer)
985 {
986         struct sockaddr_iucv *siucv = (struct sockaddr_iucv *) addr;
987         struct sock *sk = sock->sk;
988         struct iucv_sock *iucv = iucv_sk(sk);
989 
990         addr->sa_family = AF_IUCV;
991         *len = sizeof(struct sockaddr_iucv);
992 
993         if (peer) {
994                 memcpy(siucv->siucv_user_id, iucv->dst_user_id, 8);
995                 memcpy(siucv->siucv_name, iucv->dst_name, 8);
996         } else {
997                 memcpy(siucv->siucv_user_id, iucv->src_user_id, 8);
998                 memcpy(siucv->siucv_name, iucv->src_name, 8);
999         }
1000         memset(&siucv->siucv_port, 0, sizeof(siucv->siucv_port));
1001         memset(&siucv->siucv_addr, 0, sizeof(siucv->siucv_addr));
1002         memset(&siucv->siucv_nodeid, 0, sizeof(siucv->siucv_nodeid));
1003 
1004         return 0;
1005 }
1006 
1007 /**
1008  * iucv_send_iprm() - Send socket data in parameter list of an iucv message.
1009  * @path:       IUCV path
1010  * @msg:        Pointer to a struct iucv_message
1011  * @skb:        The socket data to send, skb->len MUST BE <= 7
1012  *
1013  * Send the socket data in the parameter list in the iucv message
1014  * (IUCV_IPRMDATA). The socket data is stored at index 0 to 6 in the parameter
1015  * list and the socket data len at index 7 (last byte).
1016  * See also iucv_msg_length().
1017  *
1018  * Returns the error code from the iucv_message_send() call.
1019  */
1020 static int iucv_send_iprm(struct iucv_path *path, struct iucv_message *msg,
1021                           struct sk_buff *skb)
1022 {
1023         u8 prmdata[8];
1024 
1025         memcpy(prmdata, (void *) skb->data, skb->len);
1026         prmdata[7] = 0xff - (u8) skb->len;
1027         return pr_iucv->message_send(path, msg, IUCV_IPRMDATA, 0,
1028                                  (void *) prmdata, 8);
1029 }
1030 
1031 static int iucv_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
1032                              struct msghdr *msg, size_t len)
1033 {
1034         struct sock *sk = sock->sk;
1035         struct iucv_sock *iucv = iucv_sk(sk);
1036         struct sk_buff *skb;
1037         struct iucv_message txmsg;
1038         struct cmsghdr *cmsg;
1039         int cmsg_done;
1040         long timeo;
1041         char user_id[9];
1042         char appl_id[9];
1043         int err;
1044         int noblock = msg->msg_flags & MSG_DONTWAIT;
1045 
1046         err = sock_error(sk);
1047         if (err)
1048                 return err;
1049 
1050         if (msg->msg_flags & MSG_OOB)
1051                 return -EOPNOTSUPP;
1052 
1053         /* SOCK_SEQPACKET: we do not support segmented records */
1054         if (sk->sk_type == SOCK_SEQPACKET && !(msg->msg_flags & MSG_EOR))
1055                 return -EOPNOTSUPP;
1056 
1057         lock_sock(sk);
1058 
1059         if (sk->sk_shutdown & SEND_SHUTDOWN) {
1060                 err = -EPIPE;
1061                 goto out;
1062         }
1063 
1064         /* Return if the socket is not in connected state */
1065         if (sk->sk_state != IUCV_CONNECTED) {
1066                 err = -ENOTCONN;
1067                 goto out;
1068         }
1069 
1070         /* initialize defaults */
1071         cmsg_done   = 0;        /* check for duplicate headers */
1072         txmsg.class = 0;
1073 
1074         /* iterate over control messages */
1075         for (cmsg = CMSG_FIRSTHDR(msg); cmsg;
1076                 cmsg = CMSG_NXTHDR(msg, cmsg)) {
1077 
1078                 if (!CMSG_OK(msg, cmsg)) {
1079                         err = -EINVAL;
1080                         goto out;
1081                 }
1082 
1083                 if (cmsg->cmsg_level != SOL_IUCV)
1084                         continue;
1085 
1086                 if (cmsg->cmsg_type & cmsg_done) {
1087                         err = -EINVAL;
1088                         goto out;
1089                 }
1090                 cmsg_done |= cmsg->cmsg_type;
1091 
1092                 switch (cmsg->cmsg_type) {
1093                 case SCM_IUCV_TRGCLS:
1094                         if (cmsg->cmsg_len != CMSG_LEN(TRGCLS_SIZE)) {
1095                                 err = -EINVAL;
1096                                 goto out;
1097                         }
1098 
1099                         /* set iucv message target class */
1100                         memcpy(&txmsg.class,
1101                                 (void *) CMSG_DATA(cmsg), TRGCLS_SIZE);
1102 
1103                         break;
1104 
1105                 default:
1106                         err = -EINVAL;
1107                         goto out;
1108                         break;
1109                 }
1110         }
1111 
1112         /* allocate one skb for each iucv message:
1113          * this is fine for SOCK_SEQPACKET (unless we want to support
1114          * segmented records using the MSG_EOR flag), but
1115          * for SOCK_STREAM we might want to improve it in future */
1116         if (iucv->transport == AF_IUCV_TRANS_HIPER)
1117                 skb = sock_alloc_send_skb(sk,
1118                         len + sizeof(struct af_iucv_trans_hdr) + ETH_HLEN,
1119                         noblock, &err);
1120         else
1121                 skb = sock_alloc_send_skb(sk, len, noblock, &err);
1122         if (!skb) {
1123                 err = -ENOMEM;
1124                 goto out;
1125         }
1126         if (iucv->transport == AF_IUCV_TRANS_HIPER)
1127                 skb_reserve(skb, sizeof(struct af_iucv_trans_hdr) + ETH_HLEN);
1128         if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
1129                 err = -EFAULT;
1130                 goto fail;
1131         }
1132 
1133         /* wait if outstanding messages for iucv path has reached */
1134         timeo = sock_sndtimeo(sk, noblock);
1135         err = iucv_sock_wait(sk, iucv_below_msglim(sk), timeo);
1136         if (err)
1137                 goto fail;
1138 
1139         /* return -ECONNRESET if the socket is no longer connected */
1140         if (sk->sk_state != IUCV_CONNECTED) {
1141                 err = -ECONNRESET;
1142                 goto fail;
1143         }
1144 
1145         /* increment and save iucv message tag for msg_completion cbk */
1146         txmsg.tag = iucv->send_tag++;
1147         memcpy(CB_TAG(skb), &txmsg.tag, CB_TAG_LEN);
1148 
1149         if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1150                 atomic_inc(&iucv->msg_sent);
1151                 err = afiucv_hs_send(&txmsg, sk, skb, 0);
1152                 if (err) {
1153                         atomic_dec(&iucv->msg_sent);
1154                         goto fail;
1155                 }
1156                 goto release;
1157         }
1158         skb_queue_tail(&iucv->send_skb_q, skb);
1159 
1160         if (((iucv->path->flags & IUCV_IPRMDATA) & iucv->flags)
1161               && skb->len <= 7) {
1162                 err = iucv_send_iprm(iucv->path, &txmsg, skb);
1163 
1164                 /* on success: there is no message_complete callback
1165                  * for an IPRMDATA msg; remove skb from send queue */
1166                 if (err == 0) {
1167                         skb_unlink(skb, &iucv->send_skb_q);
1168                         kfree_skb(skb);
1169                 }
1170 
1171                 /* this error should never happen since the
1172                  * IUCV_IPRMDATA path flag is set... sever path */
1173                 if (err == 0x15) {
1174                         pr_iucv->path_sever(iucv->path, NULL);
1175                         skb_unlink(skb, &iucv->send_skb_q);
1176                         err = -EPIPE;
1177                         goto fail;
1178                 }
1179         } else
1180                 err = pr_iucv->message_send(iucv->path, &txmsg, 0, 0,
1181                                         (void *) skb->data, skb->len);
1182         if (err) {
1183                 if (err == 3) {
1184                         user_id[8] = 0;
1185                         memcpy(user_id, iucv->dst_user_id, 8);
1186                         appl_id[8] = 0;
1187                         memcpy(appl_id, iucv->dst_name, 8);
1188                         pr_err("Application %s on z/VM guest %s"
1189                                 " exceeds message limit\n",
1190                                 appl_id, user_id);
1191                         err = -EAGAIN;
1192                 } else
1193                         err = -EPIPE;
1194                 skb_unlink(skb, &iucv->send_skb_q);
1195                 goto fail;
1196         }
1197 
1198 release:
1199         release_sock(sk);
1200         return len;
1201 
1202 fail:
1203         kfree_skb(skb);
1204 out:
1205         release_sock(sk);
1206         return err;
1207 }
1208 
1209 /* iucv_fragment_skb() - Fragment a single IUCV message into multiple skb's
1210  *
1211  * Locking: must be called with message_q.lock held
1212  */
1213 static int iucv_fragment_skb(struct sock *sk, struct sk_buff *skb, int len)
1214 {
1215         int dataleft, size, copied = 0;
1216         struct sk_buff *nskb;
1217 
1218         dataleft = len;
1219         while (dataleft) {
1220                 if (dataleft >= sk->sk_rcvbuf / 4)
1221                         size = sk->sk_rcvbuf / 4;
1222                 else
1223                         size = dataleft;
1224 
1225                 nskb = alloc_skb(size, GFP_ATOMIC | GFP_DMA);
1226                 if (!nskb)
1227                         return -ENOMEM;
1228 
1229                 /* copy target class to control buffer of new skb */
1230                 memcpy(CB_TRGCLS(nskb), CB_TRGCLS(skb), CB_TRGCLS_LEN);
1231 
1232                 /* copy data fragment */
1233                 memcpy(nskb->data, skb->data + copied, size);
1234                 copied += size;
1235                 dataleft -= size;
1236 
1237                 skb_reset_transport_header(nskb);
1238                 skb_reset_network_header(nskb);
1239                 nskb->len = size;
1240 
1241                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, nskb);
1242         }
1243 
1244         return 0;
1245 }
1246 
1247 /* iucv_process_message() - Receive a single outstanding IUCV message
1248  *
1249  * Locking: must be called with message_q.lock held
1250  */
1251 static void iucv_process_message(struct sock *sk, struct sk_buff *skb,
1252                                  struct iucv_path *path,
1253                                  struct iucv_message *msg)
1254 {
1255         int rc;
1256         unsigned int len;
1257 
1258         len = iucv_msg_length(msg);
1259 
1260         /* store msg target class in the second 4 bytes of skb ctrl buffer */
1261         /* Note: the first 4 bytes are reserved for msg tag */
1262         memcpy(CB_TRGCLS(skb), &msg->class, CB_TRGCLS_LEN);
1263 
1264         /* check for special IPRM messages (e.g. iucv_sock_shutdown) */
1265         if ((msg->flags & IUCV_IPRMDATA) && len > 7) {
1266                 if (memcmp(msg->rmmsg, iprm_shutdown, 8) == 0) {
1267                         skb->data = NULL;
1268                         skb->len = 0;
1269                 }
1270         } else {
1271                 rc = pr_iucv->message_receive(path, msg,
1272                                               msg->flags & IUCV_IPRMDATA,
1273                                               skb->data, len, NULL);
1274                 if (rc) {
1275                         kfree_skb(skb);
1276                         return;
1277                 }
1278                 /* we need to fragment iucv messages for SOCK_STREAM only;
1279                  * for SOCK_SEQPACKET, it is only relevant if we support
1280                  * record segmentation using MSG_EOR (see also recvmsg()) */
1281                 if (sk->sk_type == SOCK_STREAM &&
1282                     skb->truesize >= sk->sk_rcvbuf / 4) {
1283                         rc = iucv_fragment_skb(sk, skb, len);
1284                         kfree_skb(skb);
1285                         skb = NULL;
1286                         if (rc) {
1287                                 pr_iucv->path_sever(path, NULL);
1288                                 return;
1289                         }
1290                         skb = skb_dequeue(&iucv_sk(sk)->backlog_skb_q);
1291                 } else {
1292                         skb_reset_transport_header(skb);
1293                         skb_reset_network_header(skb);
1294                         skb->len = len;
1295                 }
1296         }
1297 
1298         if (sock_queue_rcv_skb(sk, skb))
1299                 skb_queue_head(&iucv_sk(sk)->backlog_skb_q, skb);
1300 }
1301 
1302 /* iucv_process_message_q() - Process outstanding IUCV messages
1303  *
1304  * Locking: must be called with message_q.lock held
1305  */
1306 static void iucv_process_message_q(struct sock *sk)
1307 {
1308         struct iucv_sock *iucv = iucv_sk(sk);
1309         struct sk_buff *skb;
1310         struct sock_msg_q *p, *n;
1311 
1312         list_for_each_entry_safe(p, n, &iucv->message_q.list, list) {
1313                 skb = alloc_skb(iucv_msg_length(&p->msg), GFP_ATOMIC | GFP_DMA);
1314                 if (!skb)
1315                         break;
1316                 iucv_process_message(sk, skb, p->path, &p->msg);
1317                 list_del(&p->list);
1318                 kfree(p);
1319                 if (!skb_queue_empty(&iucv->backlog_skb_q))
1320                         break;
1321         }
1322 }
1323 
1324 static int iucv_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
1325                              struct msghdr *msg, size_t len, int flags)
1326 {
1327         int noblock = flags & MSG_DONTWAIT;
1328         struct sock *sk = sock->sk;
1329         struct iucv_sock *iucv = iucv_sk(sk);
1330         unsigned int copied, rlen;
1331         struct sk_buff *skb, *rskb, *cskb;
1332         int err = 0;
1333 
1334         if ((sk->sk_state == IUCV_DISCONN) &&
1335             skb_queue_empty(&iucv->backlog_skb_q) &&
1336             skb_queue_empty(&sk->sk_receive_queue) &&
1337             list_empty(&iucv->message_q.list))
1338                 return 0;
1339 
1340         if (flags & (MSG_OOB))
1341                 return -EOPNOTSUPP;
1342 
1343         /* receive/dequeue next skb:
1344          * the function understands MSG_PEEK and, thus, does not dequeue skb */
1345         skb = skb_recv_datagram(sk, flags, noblock, &err);
1346         if (!skb) {
1347                 if (sk->sk_shutdown & RCV_SHUTDOWN)
1348                         return 0;
1349                 return err;
1350         }
1351 
1352         rlen   = skb->len;              /* real length of skb */
1353         copied = min_t(unsigned int, rlen, len);
1354         if (!rlen)
1355                 sk->sk_shutdown = sk->sk_shutdown | RCV_SHUTDOWN;
1356 
1357         cskb = skb;
1358         if (skb_copy_datagram_iovec(cskb, 0, msg->msg_iov, copied)) {
1359                 if (!(flags & MSG_PEEK))
1360                         skb_queue_head(&sk->sk_receive_queue, skb);
1361                 return -EFAULT;
1362         }
1363 
1364         /* SOCK_SEQPACKET: set MSG_TRUNC if recv buf size is too small */
1365         if (sk->sk_type == SOCK_SEQPACKET) {
1366                 if (copied < rlen)
1367                         msg->msg_flags |= MSG_TRUNC;
1368                 /* each iucv message contains a complete record */
1369                 msg->msg_flags |= MSG_EOR;
1370         }
1371 
1372         /* create control message to store iucv msg target class:
1373          * get the trgcls from the control buffer of the skb due to
1374          * fragmentation of original iucv message. */
1375         err = put_cmsg(msg, SOL_IUCV, SCM_IUCV_TRGCLS,
1376                         CB_TRGCLS_LEN, CB_TRGCLS(skb));
1377         if (err) {
1378                 if (!(flags & MSG_PEEK))
1379                         skb_queue_head(&sk->sk_receive_queue, skb);
1380                 return err;
1381         }
1382 
1383         /* Mark read part of skb as used */
1384         if (!(flags & MSG_PEEK)) {
1385 
1386                 /* SOCK_STREAM: re-queue skb if it contains unreceived data */
1387                 if (sk->sk_type == SOCK_STREAM) {
1388                         skb_pull(skb, copied);
1389                         if (skb->len) {
1390                                 skb_queue_head(&sk->sk_receive_queue, skb);
1391                                 goto done;
1392                         }
1393                 }
1394 
1395                 kfree_skb(skb);
1396                 if (iucv->transport == AF_IUCV_TRANS_HIPER) {
1397                         atomic_inc(&iucv->msg_recv);
1398                         if (atomic_read(&iucv->msg_recv) > iucv->msglimit) {
1399                                 WARN_ON(1);
1400                                 iucv_sock_close(sk);
1401                                 return -EFAULT;
1402                         }
1403                 }
1404 
1405                 /* Queue backlog skbs */
1406                 spin_lock_bh(&iucv->message_q.lock);
1407                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1408                 while (rskb) {
1409                         if (sock_queue_rcv_skb(sk, rskb)) {
1410                                 skb_queue_head(&iucv->backlog_skb_q,
1411                                                 rskb);
1412                                 break;
1413                         } else {
1414                                 rskb = skb_dequeue(&iucv->backlog_skb_q);
1415                         }
1416                 }
1417                 if (skb_queue_empty(&iucv->backlog_skb_q)) {
1418                         if (!list_empty(&iucv->message_q.list))
1419                                 iucv_process_message_q(sk);
1420                         if (atomic_read(&iucv->msg_recv) >=
1421                                                         iucv->msglimit / 2) {
1422                                 err = iucv_send_ctrl(sk, AF_IUCV_FLAG_WIN);
1423                                 if (err) {
1424                                         sk->sk_state = IUCV_DISCONN;
1425                                         sk->sk_state_change(sk);
1426                                 }
1427                         }
1428                 }
1429                 spin_unlock_bh(&iucv->message_q.lock);
1430         }
1431 
1432 done:
1433         /* SOCK_SEQPACKET: return real length if MSG_TRUNC is set */
1434         if (sk->sk_type == SOCK_SEQPACKET && (flags & MSG_TRUNC))
1435                 copied = rlen;
1436 
1437         return copied;
1438 }
1439 
1440 static inline unsigned int iucv_accept_poll(struct sock *parent)
1441 {
1442         struct iucv_sock *isk, *n;
1443         struct sock *sk;
1444 
1445         list_for_each_entry_safe(isk, n, &iucv_sk(parent)->accept_q, accept_q) {
1446                 sk = (struct sock *) isk;
1447 
1448                 if (sk->sk_state == IUCV_CONNECTED)
1449                         return POLLIN | POLLRDNORM;
1450         }
1451 
1452         return 0;
1453 }
1454 
1455 unsigned int iucv_sock_poll(struct file *file, struct socket *sock,
1456                             poll_table *wait)
1457 {
1458         struct sock *sk = sock->sk;
1459         unsigned int mask = 0;
1460 
1461         sock_poll_wait(file, sk_sleep(sk), wait);
1462 
1463         if (sk->sk_state == IUCV_LISTEN)
1464                 return iucv_accept_poll(sk);
1465 
1466         if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
1467                 mask |= POLLERR;
1468 
1469         if (sk->sk_shutdown & RCV_SHUTDOWN)
1470                 mask |= POLLRDHUP;
1471 
1472         if (sk->sk_shutdown == SHUTDOWN_MASK)
1473                 mask |= POLLHUP;
1474 
1475         if (!skb_queue_empty(&sk->sk_receive_queue) ||
1476             (sk->sk_shutdown & RCV_SHUTDOWN))
1477                 mask |= POLLIN | POLLRDNORM;
1478 
1479         if (sk->sk_state == IUCV_CLOSED)
1480                 mask |= POLLHUP;
1481 
1482         if (sk->sk_state == IUCV_DISCONN)
1483                 mask |= POLLIN;
1484 
1485         if (sock_writeable(sk) && iucv_below_msglim(sk))
1486                 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
1487         else
1488                 set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
1489 
1490         return mask;
1491 }
1492 
1493 static int iucv_sock_shutdown(struct socket *sock, int how)
1494 {
1495         struct sock *sk = sock->sk;
1496         struct iucv_sock *iucv = iucv_sk(sk);
1497         struct iucv_message txmsg;
1498         int err = 0;
1499 
1500         how++;
1501 
1502         if ((how & ~SHUTDOWN_MASK) || !how)
1503                 return -EINVAL;
1504 
1505         lock_sock(sk);
1506         switch (sk->sk_state) {
1507         case IUCV_LISTEN:
1508         case IUCV_DISCONN:
1509         case IUCV_CLOSING:
1510         case IUCV_CLOSED:
1511                 err = -ENOTCONN;
1512                 goto fail;
1513         default:
1514                 break;
1515         }
1516 
1517         if (how == SEND_SHUTDOWN || how == SHUTDOWN_MASK) {
1518                 if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1519                         txmsg.class = 0;
1520                         txmsg.tag = 0;
1521                         err = pr_iucv->message_send(iucv->path, &txmsg,
1522                                 IUCV_IPRMDATA, 0, (void *) iprm_shutdown, 8);
1523                         if (err) {
1524                                 switch (err) {
1525                                 case 1:
1526                                         err = -ENOTCONN;
1527                                         break;
1528                                 case 2:
1529                                         err = -ECONNRESET;
1530                                         break;
1531                                 default:
1532                                         err = -ENOTCONN;
1533                                         break;
1534                                 }
1535                         }
1536                 } else
1537                         iucv_send_ctrl(sk, AF_IUCV_FLAG_SHT);
1538         }
1539 
1540         sk->sk_shutdown |= how;
1541         if (how == RCV_SHUTDOWN || how == SHUTDOWN_MASK) {
1542                 if (iucv->transport == AF_IUCV_TRANS_IUCV) {
1543                         err = pr_iucv->path_quiesce(iucv->path, NULL);
1544                         if (err)
1545                                 err = -ENOTCONN;
1546 /*                      skb_queue_purge(&sk->sk_receive_queue); */
1547                 }
1548                 skb_queue_purge(&sk->sk_receive_queue);
1549         }
1550 
1551         /* Wake up anyone sleeping in poll */
1552         sk->sk_state_change(sk);
1553 
1554 fail:
1555         release_sock(sk);
1556         return err;
1557 }
1558 
1559 static int iucv_sock_release(struct socket *sock)
1560 {
1561         struct sock *sk = sock->sk;
1562         int err = 0;
1563 
1564         if (!sk)
1565                 return 0;
1566 
1567         iucv_sock_close(sk);
1568 
1569         sock_orphan(sk);
1570         iucv_sock_kill(sk);
1571         return err;
1572 }
1573 
1574 /* getsockopt and setsockopt */
1575 static int iucv_sock_setsockopt(struct socket *sock, int level, int optname,
1576                                 char __user *optval, unsigned int optlen)
1577 {
1578         struct sock *sk = sock->sk;
1579         struct iucv_sock *iucv = iucv_sk(sk);
1580         int val;
1581         int rc;
1582 
1583         if (level != SOL_IUCV)
1584                 return -ENOPROTOOPT;
1585 
1586         if (optlen < sizeof(int))
1587                 return -EINVAL;
1588 
1589         if (get_user(val, (int __user *) optval))
1590                 return -EFAULT;
1591 
1592         rc = 0;
1593 
1594         lock_sock(sk);
1595         switch (optname) {
1596         case SO_IPRMDATA_MSG:
1597                 if (val)
1598                         iucv->flags |= IUCV_IPRMDATA;
1599                 else
1600                         iucv->flags &= ~IUCV_IPRMDATA;
1601                 break;
1602         case SO_MSGLIMIT:
1603                 switch (sk->sk_state) {
1604                 case IUCV_OPEN:
1605                 case IUCV_BOUND:
1606                         if (val < 1 || val > (u16)(~0))
1607                                 rc = -EINVAL;
1608                         else
1609                                 iucv->msglimit = val;
1610                         break;
1611                 default:
1612                         rc = -EINVAL;
1613                         break;
1614                 }
1615                 break;
1616         default:
1617                 rc = -ENOPROTOOPT;
1618                 break;
1619         }
1620         release_sock(sk);
1621 
1622         return rc;
1623 }
1624 
1625 static int iucv_sock_getsockopt(struct socket *sock, int level, int optname,
1626                                 char __user *optval, int __user *optlen)
1627 {
1628         struct sock *sk = sock->sk;
1629         struct iucv_sock *iucv = iucv_sk(sk);
1630         unsigned int val;
1631         int len;
1632 
1633         if (level != SOL_IUCV)
1634                 return -ENOPROTOOPT;
1635 
1636         if (get_user(len, optlen))
1637                 return -EFAULT;
1638 
1639         if (len < 0)
1640                 return -EINVAL;
1641 
1642         len = min_t(unsigned int, len, sizeof(int));
1643 
1644         switch (optname) {
1645         case SO_IPRMDATA_MSG:
1646                 val = (iucv->flags & IUCV_IPRMDATA) ? 1 : 0;
1647                 break;
1648         case SO_MSGLIMIT:
1649                 lock_sock(sk);
1650                 val = (iucv->path != NULL) ? iucv->path->msglim /* connected */
1651                                            : iucv->msglimit;    /* default */
1652                 release_sock(sk);
1653                 break;
1654         case SO_MSGSIZE:
1655                 if (sk->sk_state == IUCV_OPEN)
1656                         return -EBADFD;
1657                 val = (iucv->hs_dev) ? iucv->hs_dev->mtu -
1658                                 sizeof(struct af_iucv_trans_hdr) - ETH_HLEN :
1659                                 0x7fffffff;
1660                 break;
1661         default:
1662                 return -ENOPROTOOPT;
1663         }
1664 
1665         if (put_user(len, optlen))
1666                 return -EFAULT;
1667         if (copy_to_user(optval, &val, len))
1668                 return -EFAULT;
1669 
1670         return 0;
1671 }
1672 
1673 
1674 /* Callback wrappers - called from iucv base support */
1675 static int iucv_callback_connreq(struct iucv_path *path,
1676                                  u8 ipvmid[8], u8 ipuser[16])
1677 {
1678         unsigned char user_data[16];
1679         unsigned char nuser_data[16];
1680         unsigned char src_name[8];
1681         struct hlist_node *node;
1682         struct sock *sk, *nsk;
1683         struct iucv_sock *iucv, *niucv;
1684         int err;
1685 
1686         memcpy(src_name, ipuser, 8);
1687         EBCASC(src_name, 8);
1688         /* Find out if this path belongs to af_iucv. */
1689         read_lock(&iucv_sk_list.lock);
1690         iucv = NULL;
1691         sk = NULL;
1692         sk_for_each(sk, node, &iucv_sk_list.head)
1693                 if (sk->sk_state == IUCV_LISTEN &&
1694                     !memcmp(&iucv_sk(sk)->src_name, src_name, 8)) {
1695                         /*
1696                          * Found a listening socket with
1697                          * src_name == ipuser[0-7].
1698                          */
1699                         iucv = iucv_sk(sk);
1700                         break;
1701                 }
1702         read_unlock(&iucv_sk_list.lock);
1703         if (!iucv)
1704                 /* No socket found, not one of our paths. */
1705                 return -EINVAL;
1706 
1707         bh_lock_sock(sk);
1708 
1709         /* Check if parent socket is listening */
1710         low_nmcpy(user_data, iucv->src_name);
1711         high_nmcpy(user_data, iucv->dst_name);
1712         ASCEBC(user_data, sizeof(user_data));
1713         if (sk->sk_state != IUCV_LISTEN) {
1714                 err = pr_iucv->path_sever(path, user_data);
1715                 iucv_path_free(path);
1716                 goto fail;
1717         }
1718 
1719         /* Check for backlog size */
1720         if (sk_acceptq_is_full(sk)) {
1721                 err = pr_iucv->path_sever(path, user_data);
1722                 iucv_path_free(path);
1723                 goto fail;
1724         }
1725 
1726         /* Create the new socket */
1727         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1728         if (!nsk) {
1729                 err = pr_iucv->path_sever(path, user_data);
1730                 iucv_path_free(path);
1731                 goto fail;
1732         }
1733 
1734         niucv = iucv_sk(nsk);
1735         iucv_sock_init(nsk, sk);
1736 
1737         /* Set the new iucv_sock */
1738         memcpy(niucv->dst_name, ipuser + 8, 8);
1739         EBCASC(niucv->dst_name, 8);
1740         memcpy(niucv->dst_user_id, ipvmid, 8);
1741         memcpy(niucv->src_name, iucv->src_name, 8);
1742         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1743         niucv->path = path;
1744 
1745         /* Call iucv_accept */
1746         high_nmcpy(nuser_data, ipuser + 8);
1747         memcpy(nuser_data + 8, niucv->src_name, 8);
1748         ASCEBC(nuser_data + 8, 8);
1749 
1750         /* set message limit for path based on msglimit of accepting socket */
1751         niucv->msglimit = iucv->msglimit;
1752         path->msglim = iucv->msglimit;
1753         err = pr_iucv->path_accept(path, &af_iucv_handler, nuser_data, nsk);
1754         if (err) {
1755                 iucv_sever_path(nsk, 1);
1756                 iucv_sock_kill(nsk);
1757                 goto fail;
1758         }
1759 
1760         iucv_accept_enqueue(sk, nsk);
1761 
1762         /* Wake up accept */
1763         nsk->sk_state = IUCV_CONNECTED;
1764         sk->sk_data_ready(sk, 1);
1765         err = 0;
1766 fail:
1767         bh_unlock_sock(sk);
1768         return 0;
1769 }
1770 
1771 static void iucv_callback_connack(struct iucv_path *path, u8 ipuser[16])
1772 {
1773         struct sock *sk = path->private;
1774 
1775         sk->sk_state = IUCV_CONNECTED;
1776         sk->sk_state_change(sk);
1777 }
1778 
1779 static void iucv_callback_rx(struct iucv_path *path, struct iucv_message *msg)
1780 {
1781         struct sock *sk = path->private;
1782         struct iucv_sock *iucv = iucv_sk(sk);
1783         struct sk_buff *skb;
1784         struct sock_msg_q *save_msg;
1785         int len;
1786 
1787         if (sk->sk_shutdown & RCV_SHUTDOWN) {
1788                 pr_iucv->message_reject(path, msg);
1789                 return;
1790         }
1791 
1792         spin_lock(&iucv->message_q.lock);
1793 
1794         if (!list_empty(&iucv->message_q.list) ||
1795             !skb_queue_empty(&iucv->backlog_skb_q))
1796                 goto save_message;
1797 
1798         len = atomic_read(&sk->sk_rmem_alloc);
1799         len += SKB_TRUESIZE(iucv_msg_length(msg));
1800         if (len > sk->sk_rcvbuf)
1801                 goto save_message;
1802 
1803         skb = alloc_skb(iucv_msg_length(msg), GFP_ATOMIC | GFP_DMA);
1804         if (!skb)
1805                 goto save_message;
1806 
1807         iucv_process_message(sk, skb, path, msg);
1808         goto out_unlock;
1809 
1810 save_message:
1811         save_msg = kzalloc(sizeof(struct sock_msg_q), GFP_ATOMIC | GFP_DMA);
1812         if (!save_msg)
1813                 goto out_unlock;
1814         save_msg->path = path;
1815         save_msg->msg = *msg;
1816 
1817         list_add_tail(&save_msg->list, &iucv->message_q.list);
1818 
1819 out_unlock:
1820         spin_unlock(&iucv->message_q.lock);
1821 }
1822 
1823 static void iucv_callback_txdone(struct iucv_path *path,
1824                                  struct iucv_message *msg)
1825 {
1826         struct sock *sk = path->private;
1827         struct sk_buff *this = NULL;
1828         struct sk_buff_head *list = &iucv_sk(sk)->send_skb_q;
1829         struct sk_buff *list_skb = list->next;
1830         unsigned long flags;
1831 
1832         bh_lock_sock(sk);
1833         if (!skb_queue_empty(list)) {
1834                 spin_lock_irqsave(&list->lock, flags);
1835 
1836                 while (list_skb != (struct sk_buff *)list) {
1837                         if (!memcmp(&msg->tag, CB_TAG(list_skb), CB_TAG_LEN)) {
1838                                 this = list_skb;
1839                                 break;
1840                         }
1841                         list_skb = list_skb->next;
1842                 }
1843                 if (this)
1844                         __skb_unlink(this, list);
1845 
1846                 spin_unlock_irqrestore(&list->lock, flags);
1847 
1848                 if (this) {
1849                         kfree_skb(this);
1850                         /* wake up any process waiting for sending */
1851                         iucv_sock_wake_msglim(sk);
1852                 }
1853         }
1854 
1855         if (sk->sk_state == IUCV_CLOSING) {
1856                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
1857                         sk->sk_state = IUCV_CLOSED;
1858                         sk->sk_state_change(sk);
1859                 }
1860         }
1861         bh_unlock_sock(sk);
1862 
1863 }
1864 
1865 static void iucv_callback_connrej(struct iucv_path *path, u8 ipuser[16])
1866 {
1867         struct sock *sk = path->private;
1868 
1869         if (sk->sk_state == IUCV_CLOSED)
1870                 return;
1871 
1872         bh_lock_sock(sk);
1873         iucv_sever_path(sk, 1);
1874         sk->sk_state = IUCV_DISCONN;
1875 
1876         sk->sk_state_change(sk);
1877         bh_unlock_sock(sk);
1878 }
1879 
1880 /* called if the other communication side shuts down its RECV direction;
1881  * in turn, the callback sets SEND_SHUTDOWN to disable sending of data.
1882  */
1883 static void iucv_callback_shutdown(struct iucv_path *path, u8 ipuser[16])
1884 {
1885         struct sock *sk = path->private;
1886 
1887         bh_lock_sock(sk);
1888         if (sk->sk_state != IUCV_CLOSED) {
1889                 sk->sk_shutdown |= SEND_SHUTDOWN;
1890                 sk->sk_state_change(sk);
1891         }
1892         bh_unlock_sock(sk);
1893 }
1894 
1895 /***************** HiperSockets transport callbacks ********************/
1896 static void afiucv_swap_src_dest(struct sk_buff *skb)
1897 {
1898         struct af_iucv_trans_hdr *trans_hdr =
1899                                 (struct af_iucv_trans_hdr *)skb->data;
1900         char tmpID[8];
1901         char tmpName[8];
1902 
1903         ASCEBC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
1904         ASCEBC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
1905         ASCEBC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
1906         ASCEBC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
1907         memcpy(tmpID, trans_hdr->srcUserID, 8);
1908         memcpy(tmpName, trans_hdr->srcAppName, 8);
1909         memcpy(trans_hdr->srcUserID, trans_hdr->destUserID, 8);
1910         memcpy(trans_hdr->srcAppName, trans_hdr->destAppName, 8);
1911         memcpy(trans_hdr->destUserID, tmpID, 8);
1912         memcpy(trans_hdr->destAppName, tmpName, 8);
1913         skb_push(skb, ETH_HLEN);
1914         memset(skb->data, 0, ETH_HLEN);
1915 }
1916 
1917 /**
1918  * afiucv_hs_callback_syn - react on received SYN
1919  **/
1920 static int afiucv_hs_callback_syn(struct sock *sk, struct sk_buff *skb)
1921 {
1922         struct sock *nsk;
1923         struct iucv_sock *iucv, *niucv;
1924         struct af_iucv_trans_hdr *trans_hdr;
1925         int err;
1926 
1927         iucv = iucv_sk(sk);
1928         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
1929         if (!iucv) {
1930                 /* no sock - connection refused */
1931                 afiucv_swap_src_dest(skb);
1932                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1933                 err = dev_queue_xmit(skb);
1934                 goto out;
1935         }
1936 
1937         nsk = iucv_sock_alloc(NULL, sk->sk_type, GFP_ATOMIC);
1938         bh_lock_sock(sk);
1939         if ((sk->sk_state != IUCV_LISTEN) ||
1940             sk_acceptq_is_full(sk) ||
1941             !nsk) {
1942                 /* error on server socket - connection refused */
1943                 if (nsk)
1944                         sk_free(nsk);
1945                 afiucv_swap_src_dest(skb);
1946                 trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN;
1947                 err = dev_queue_xmit(skb);
1948                 bh_unlock_sock(sk);
1949                 goto out;
1950         }
1951 
1952         niucv = iucv_sk(nsk);
1953         iucv_sock_init(nsk, sk);
1954         niucv->transport = AF_IUCV_TRANS_HIPER;
1955         niucv->msglimit = iucv->msglimit;
1956         if (!trans_hdr->window)
1957                 niucv->msglimit_peer = IUCV_HIPER_MSGLIM_DEFAULT;
1958         else
1959                 niucv->msglimit_peer = trans_hdr->window;
1960         memcpy(niucv->dst_name, trans_hdr->srcAppName, 8);
1961         memcpy(niucv->dst_user_id, trans_hdr->srcUserID, 8);
1962         memcpy(niucv->src_name, iucv->src_name, 8);
1963         memcpy(niucv->src_user_id, iucv->src_user_id, 8);
1964         nsk->sk_bound_dev_if = sk->sk_bound_dev_if;
1965         niucv->hs_dev = iucv->hs_dev;
1966         dev_hold(niucv->hs_dev);
1967         afiucv_swap_src_dest(skb);
1968         trans_hdr->flags = AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK;
1969         trans_hdr->window = niucv->msglimit;
1970         /* if receiver acks the xmit connection is established */
1971         err = dev_queue_xmit(skb);
1972         if (!err) {
1973                 iucv_accept_enqueue(sk, nsk);
1974                 nsk->sk_state = IUCV_CONNECTED;
1975                 sk->sk_data_ready(sk, 1);
1976         } else
1977                 iucv_sock_kill(nsk);
1978         bh_unlock_sock(sk);
1979 
1980 out:
1981         return NET_RX_SUCCESS;
1982 }
1983 
1984 /**
1985  * afiucv_hs_callback_synack() - react on received SYN-ACK
1986  **/
1987 static int afiucv_hs_callback_synack(struct sock *sk, struct sk_buff *skb)
1988 {
1989         struct iucv_sock *iucv = iucv_sk(sk);
1990         struct af_iucv_trans_hdr *trans_hdr =
1991                                         (struct af_iucv_trans_hdr *)skb->data;
1992 
1993         if (!iucv)
1994                 goto out;
1995         if (sk->sk_state != IUCV_BOUND)
1996                 goto out;
1997         bh_lock_sock(sk);
1998         iucv->msglimit_peer = trans_hdr->window;
1999         sk->sk_state = IUCV_CONNECTED;
2000         sk->sk_state_change(sk);
2001         bh_unlock_sock(sk);
2002 out:
2003         kfree_skb(skb);
2004         return NET_RX_SUCCESS;
2005 }
2006 
2007 /**
2008  * afiucv_hs_callback_synfin() - react on received SYN_FIN
2009  **/
2010 static int afiucv_hs_callback_synfin(struct sock *sk, struct sk_buff *skb)
2011 {
2012         struct iucv_sock *iucv = iucv_sk(sk);
2013 
2014         if (!iucv)
2015                 goto out;
2016         if (sk->sk_state != IUCV_BOUND)
2017                 goto out;
2018         bh_lock_sock(sk);
2019         sk->sk_state = IUCV_DISCONN;
2020         sk->sk_state_change(sk);
2021         bh_unlock_sock(sk);
2022 out:
2023         kfree_skb(skb);
2024         return NET_RX_SUCCESS;
2025 }
2026 
2027 /**
2028  * afiucv_hs_callback_fin() - react on received FIN
2029  **/
2030 static int afiucv_hs_callback_fin(struct sock *sk, struct sk_buff *skb)
2031 {
2032         struct iucv_sock *iucv = iucv_sk(sk);
2033 
2034         /* other end of connection closed */
2035         if (!iucv)
2036                 goto out;
2037         bh_lock_sock(sk);
2038         if (sk->sk_state == IUCV_CONNECTED) {
2039                 sk->sk_state = IUCV_DISCONN;
2040                 sk->sk_state_change(sk);
2041         }
2042         bh_unlock_sock(sk);
2043 out:
2044         kfree_skb(skb);
2045         return NET_RX_SUCCESS;
2046 }
2047 
2048 /**
2049  * afiucv_hs_callback_win() - react on received WIN
2050  **/
2051 static int afiucv_hs_callback_win(struct sock *sk, struct sk_buff *skb)
2052 {
2053         struct iucv_sock *iucv = iucv_sk(sk);
2054         struct af_iucv_trans_hdr *trans_hdr =
2055                                         (struct af_iucv_trans_hdr *)skb->data;
2056 
2057         if (!iucv)
2058                 return NET_RX_SUCCESS;
2059 
2060         if (sk->sk_state != IUCV_CONNECTED)
2061                 return NET_RX_SUCCESS;
2062 
2063         atomic_sub(trans_hdr->window, &iucv->msg_sent);
2064         iucv_sock_wake_msglim(sk);
2065         return NET_RX_SUCCESS;
2066 }
2067 
2068 /**
2069  * afiucv_hs_callback_rx() - react on received data
2070  **/
2071 static int afiucv_hs_callback_rx(struct sock *sk, struct sk_buff *skb)
2072 {
2073         struct iucv_sock *iucv = iucv_sk(sk);
2074 
2075         if (!iucv) {
2076                 kfree_skb(skb);
2077                 return NET_RX_SUCCESS;
2078         }
2079 
2080         if (sk->sk_state != IUCV_CONNECTED) {
2081                 kfree_skb(skb);
2082                 return NET_RX_SUCCESS;
2083         }
2084 
2085         if (sk->sk_shutdown & RCV_SHUTDOWN) {
2086                 kfree_skb(skb);
2087                 return NET_RX_SUCCESS;
2088         }
2089 
2090                 /* write stuff from iucv_msg to skb cb */
2091         if (skb->len < sizeof(struct af_iucv_trans_hdr)) {
2092                 kfree_skb(skb);
2093                 return NET_RX_SUCCESS;
2094         }
2095         skb_pull(skb, sizeof(struct af_iucv_trans_hdr));
2096         skb_reset_transport_header(skb);
2097         skb_reset_network_header(skb);
2098         spin_lock(&iucv->message_q.lock);
2099         if (skb_queue_empty(&iucv->backlog_skb_q)) {
2100                 if (sock_queue_rcv_skb(sk, skb)) {
2101                         /* handle rcv queue full */
2102                         skb_queue_tail(&iucv->backlog_skb_q, skb);
2103                 }
2104         } else
2105                 skb_queue_tail(&iucv_sk(sk)->backlog_skb_q, skb);
2106         spin_unlock(&iucv->message_q.lock);
2107         return NET_RX_SUCCESS;
2108 }
2109 
2110 /**
2111  * afiucv_hs_rcv() - base function for arriving data through HiperSockets
2112  *                   transport
2113  *                   called from netif RX softirq
2114  **/
2115 static int afiucv_hs_rcv(struct sk_buff *skb, struct net_device *dev,
2116         struct packet_type *pt, struct net_device *orig_dev)
2117 {
2118         struct hlist_node *node;
2119         struct sock *sk;
2120         struct iucv_sock *iucv;
2121         struct af_iucv_trans_hdr *trans_hdr;
2122         char nullstring[8];
2123         int err = 0;
2124 
2125         skb_pull(skb, ETH_HLEN);
2126         trans_hdr = (struct af_iucv_trans_hdr *)skb->data;
2127         EBCASC(trans_hdr->destAppName, sizeof(trans_hdr->destAppName));
2128         EBCASC(trans_hdr->destUserID, sizeof(trans_hdr->destUserID));
2129         EBCASC(trans_hdr->srcAppName, sizeof(trans_hdr->srcAppName));
2130         EBCASC(trans_hdr->srcUserID, sizeof(trans_hdr->srcUserID));
2131         memset(nullstring, 0, sizeof(nullstring));
2132         iucv = NULL;
2133         sk = NULL;
2134         read_lock(&iucv_sk_list.lock);
2135         sk_for_each(sk, node, &iucv_sk_list.head) {
2136                 if (trans_hdr->flags == AF_IUCV_FLAG_SYN) {
2137                         if ((!memcmp(&iucv_sk(sk)->src_name,
2138                                      trans_hdr->destAppName, 8)) &&
2139                             (!memcmp(&iucv_sk(sk)->src_user_id,
2140                                      trans_hdr->destUserID, 8)) &&
2141                             (!memcmp(&iucv_sk(sk)->dst_name, nullstring, 8)) &&
2142                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2143                                      nullstring, 8))) {
2144                                 iucv = iucv_sk(sk);
2145                                 break;
2146                         }
2147                 } else {
2148                         if ((!memcmp(&iucv_sk(sk)->src_name,
2149                                      trans_hdr->destAppName, 8)) &&
2150                             (!memcmp(&iucv_sk(sk)->src_user_id,
2151                                      trans_hdr->destUserID, 8)) &&
2152                             (!memcmp(&iucv_sk(sk)->dst_name,
2153                                      trans_hdr->srcAppName, 8)) &&
2154                             (!memcmp(&iucv_sk(sk)->dst_user_id,
2155                                      trans_hdr->srcUserID, 8))) {
2156                                 iucv = iucv_sk(sk);
2157                                 break;
2158                         }
2159                 }
2160         }
2161         read_unlock(&iucv_sk_list.lock);
2162         if (!iucv)
2163                 sk = NULL;
2164 
2165         /* no sock
2166         how should we send with no sock
2167         1) send without sock no send rc checking?
2168         2) introduce default sock to handle this cases
2169 
2170          SYN -> send SYN|ACK in good case, send SYN|FIN in bad case
2171          data -> send FIN
2172          SYN|ACK, SYN|FIN, FIN -> no action? */
2173 
2174         switch (trans_hdr->flags) {
2175         case AF_IUCV_FLAG_SYN:
2176                 /* connect request */
2177                 err = afiucv_hs_callback_syn(sk, skb);
2178                 break;
2179         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_ACK):
2180                 /* connect request confirmed */
2181                 err = afiucv_hs_callback_synack(sk, skb);
2182                 break;
2183         case (AF_IUCV_FLAG_SYN | AF_IUCV_FLAG_FIN):
2184                 /* connect request refused */
2185                 err = afiucv_hs_callback_synfin(sk, skb);
2186                 break;
2187         case (AF_IUCV_FLAG_FIN):
2188                 /* close request */
2189                 err = afiucv_hs_callback_fin(sk, skb);
2190                 break;
2191         case (AF_IUCV_FLAG_WIN):
2192                 err = afiucv_hs_callback_win(sk, skb);
2193                 if (skb->len == sizeof(struct af_iucv_trans_hdr)) {
2194                         kfree_skb(skb);
2195                         break;
2196                 }
2197                 /* fall through and receive non-zero length data */
2198         case (AF_IUCV_FLAG_SHT):
2199                 /* shutdown request */
2200                 /* fall through and receive zero length data */
2201         case 0:
2202                 /* plain data frame */
2203                 memcpy(CB_TRGCLS(skb), &trans_hdr->iucv_hdr.class,
2204                        CB_TRGCLS_LEN);
2205                 err = afiucv_hs_callback_rx(sk, skb);
2206                 break;
2207         default:
2208                 ;
2209         }
2210 
2211         return err;
2212 }
2213 
2214 /**
2215  * afiucv_hs_callback_txnotify() - handle send notifcations from HiperSockets
2216  *                                 transport
2217  **/
2218 static void afiucv_hs_callback_txnotify(struct sk_buff *skb,
2219                                         enum iucv_tx_notify n)
2220 {
2221         struct sock *isk = skb->sk;
2222         struct sock *sk = NULL;
2223         struct iucv_sock *iucv = NULL;
2224         struct sk_buff_head *list;
2225         struct sk_buff *list_skb;
2226         struct sk_buff *nskb;
2227         unsigned long flags;
2228         struct hlist_node *node;
2229 
2230         read_lock_irqsave(&iucv_sk_list.lock, flags);
2231         sk_for_each(sk, node, &iucv_sk_list.head)
2232                 if (sk == isk) {
2233                         iucv = iucv_sk(sk);
2234                         break;
2235                 }
2236         read_unlock_irqrestore(&iucv_sk_list.lock, flags);
2237 
2238         if (!iucv || sock_flag(sk, SOCK_ZAPPED))
2239                 return;
2240 
2241         list = &iucv->send_skb_q;
2242         spin_lock_irqsave(&list->lock, flags);
2243         if (skb_queue_empty(list))
2244                 goto out_unlock;
2245         list_skb = list->next;
2246         nskb = list_skb->next;
2247         while (list_skb != (struct sk_buff *)list) {
2248                 if (skb_shinfo(list_skb) == skb_shinfo(skb)) {
2249                         switch (n) {
2250                         case TX_NOTIFY_OK:
2251                                 __skb_unlink(list_skb, list);
2252                                 kfree_skb(list_skb);
2253                                 iucv_sock_wake_msglim(sk);
2254                                 break;
2255                         case TX_NOTIFY_PENDING:
2256                                 atomic_inc(&iucv->pendings);
2257                                 break;
2258                         case TX_NOTIFY_DELAYED_OK:
2259                                 __skb_unlink(list_skb, list);
2260                                 atomic_dec(&iucv->pendings);
2261                                 if (atomic_read(&iucv->pendings) <= 0)
2262                                         iucv_sock_wake_msglim(sk);
2263                                 kfree_skb(list_skb);
2264                                 break;
2265                         case TX_NOTIFY_UNREACHABLE:
2266                         case TX_NOTIFY_DELAYED_UNREACHABLE:
2267                         case TX_NOTIFY_TPQFULL: /* not yet used */
2268                         case TX_NOTIFY_GENERALERROR:
2269                         case TX_NOTIFY_DELAYED_GENERALERROR:
2270                                 __skb_unlink(list_skb, list);
2271                                 kfree_skb(list_skb);
2272                                 if (sk->sk_state == IUCV_CONNECTED) {
2273                                         sk->sk_state = IUCV_DISCONN;
2274                                         sk->sk_state_change(sk);
2275                                 }
2276                                 break;
2277                         }
2278                         break;
2279                 }
2280                 list_skb = nskb;
2281                 nskb = nskb->next;
2282         }
2283 out_unlock:
2284         spin_unlock_irqrestore(&list->lock, flags);
2285 
2286         if (sk->sk_state == IUCV_CLOSING) {
2287                 if (skb_queue_empty(&iucv_sk(sk)->send_skb_q)) {
2288                         sk->sk_state = IUCV_CLOSED;
2289                         sk->sk_state_change(sk);
2290                 }
2291         }
2292 
2293 }
2294 
2295 /*
2296  * afiucv_netdev_event: handle netdev notifier chain events
2297  */
2298 static int afiucv_netdev_event(struct notifier_block *this,
2299                                unsigned long event, void *ptr)
2300 {
2301         struct net_device *event_dev = (struct net_device *)ptr;
2302         struct hlist_node *node;
2303         struct sock *sk;
2304         struct iucv_sock *iucv;
2305 
2306         switch (event) {
2307         case NETDEV_REBOOT:
2308         case NETDEV_GOING_DOWN:
2309                 sk_for_each(sk, node, &iucv_sk_list.head) {
2310                         iucv = iucv_sk(sk);
2311                         if ((iucv->hs_dev == event_dev) &&
2312                             (sk->sk_state == IUCV_CONNECTED)) {
2313                                 if (event == NETDEV_GOING_DOWN)
2314                                         iucv_send_ctrl(sk, AF_IUCV_FLAG_FIN);
2315                                 sk->sk_state = IUCV_DISCONN;
2316                                 sk->sk_state_change(sk);
2317                         }
2318                 }
2319                 break;
2320         case NETDEV_DOWN:
2321         case NETDEV_UNREGISTER:
2322         default:
2323                 break;
2324         }
2325         return NOTIFY_DONE;
2326 }
2327 
2328 static struct notifier_block afiucv_netdev_notifier = {
2329         .notifier_call = afiucv_netdev_event,
2330 };
2331 
2332 static const struct proto_ops iucv_sock_ops = {
2333         .family         = PF_IUCV,
2334         .owner          = THIS_MODULE,
2335         .release        = iucv_sock_release,
2336         .bind           = iucv_sock_bind,
2337         .connect        = iucv_sock_connect,
2338         .listen         = iucv_sock_listen,
2339         .accept         = iucv_sock_accept,
2340         .getname        = iucv_sock_getname,
2341         .sendmsg        = iucv_sock_sendmsg,
2342         .recvmsg        = iucv_sock_recvmsg,
2343         .poll           = iucv_sock_poll,
2344         .ioctl          = sock_no_ioctl,
2345         .mmap           = sock_no_mmap,
2346         .socketpair     = sock_no_socketpair,
2347         .shutdown       = iucv_sock_shutdown,
2348         .setsockopt     = iucv_sock_setsockopt,
2349         .getsockopt     = iucv_sock_getsockopt,
2350 };
2351 
2352 static const struct net_proto_family iucv_sock_family_ops = {
2353         .family = AF_IUCV,
2354         .owner  = THIS_MODULE,
2355         .create = iucv_sock_create,
2356 };
2357 
2358 static struct packet_type iucv_packet_type = {
2359         .type = cpu_to_be16(ETH_P_AF_IUCV),
2360         .func = afiucv_hs_rcv,
2361 };
2362 
2363 static int afiucv_iucv_init(void)
2364 {
2365         int err;
2366 
2367         err = pr_iucv->iucv_register(&af_iucv_handler, 0);
2368         if (err)
2369                 goto out;
2370         /* establish dummy device */
2371         af_iucv_driver.bus = pr_iucv->bus;
2372         err = driver_register(&af_iucv_driver);
2373         if (err)
2374                 goto out_iucv;
2375         af_iucv_dev = kzalloc(sizeof(struct device), GFP_KERNEL);
2376         if (!af_iucv_dev) {
2377                 err = -ENOMEM;
2378                 goto out_driver;
2379         }
2380         dev_set_name(af_iucv_dev, "af_iucv");
2381         af_iucv_dev->bus = pr_iucv->bus;
2382         af_iucv_dev->parent = pr_iucv->root;
2383         af_iucv_dev->release = (void (*)(struct device *))kfree;
2384         af_iucv_dev->driver = &af_iucv_driver;
2385         err = device_register(af_iucv_dev);
2386         if (err)
2387                 goto out_driver;
2388         return 0;
2389 
2390 out_driver:
2391         driver_unregister(&af_iucv_driver);
2392 out_iucv:
2393         pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2394 out:
2395         return err;
2396 }
2397 
2398 static int __init afiucv_init(void)
2399 {
2400         int err;
2401 
2402         if (MACHINE_IS_VM) {
2403                 cpcmd("QUERY USERID", iucv_userid, sizeof(iucv_userid), &err);
2404                 if (unlikely(err)) {
2405                         WARN_ON(err);
2406                         err = -EPROTONOSUPPORT;
2407                         goto out;
2408                 }
2409 
2410                 pr_iucv = try_then_request_module(symbol_get(iucv_if), "iucv");
2411                 if (!pr_iucv) {
2412                         printk(KERN_WARNING "iucv_if lookup failed\n");
2413                         memset(&iucv_userid, 0, sizeof(iucv_userid));
2414                 }
2415         } else {
2416                 memset(&iucv_userid, 0, sizeof(iucv_userid));
2417                 pr_iucv = NULL;
2418         }
2419 
2420         err = proto_register(&iucv_proto, 0);
2421         if (err)
2422                 goto out;
2423         err = sock_register(&iucv_sock_family_ops);
2424         if (err)
2425                 goto out_proto;
2426 
2427         if (pr_iucv) {
2428                 err = afiucv_iucv_init();
2429                 if (err)
2430                         goto out_sock;
2431         } else
2432                 register_netdevice_notifier(&afiucv_netdev_notifier);
2433         dev_add_pack(&iucv_packet_type);
2434         return 0;
2435 
2436 out_sock:
2437         sock_unregister(PF_IUCV);
2438 out_proto:
2439         proto_unregister(&iucv_proto);
2440 out:
2441         if (pr_iucv)
2442                 symbol_put(iucv_if);
2443         return err;
2444 }
2445 
2446 static void __exit afiucv_exit(void)
2447 {
2448         if (pr_iucv) {
2449                 device_unregister(af_iucv_dev);
2450                 driver_unregister(&af_iucv_driver);
2451                 pr_iucv->iucv_unregister(&af_iucv_handler, 0);
2452                 symbol_put(iucv_if);
2453         } else
2454                 unregister_netdevice_notifier(&afiucv_netdev_notifier);
2455         dev_remove_pack(&iucv_packet_type);
2456         sock_unregister(PF_IUCV);
2457         proto_unregister(&iucv_proto);
2458 }
2459 
2460 module_init(afiucv_init);
2461 module_exit(afiucv_exit);
2462 
2463 MODULE_AUTHOR("Jennifer Hunt <jenhunt@us.ibm.com>");
2464 MODULE_DESCRIPTION("IUCV Sockets ver " VERSION);
2465 MODULE_VERSION(VERSION);
2466 MODULE_LICENSE("GPL");
2467 MODULE_ALIAS_NETPROTO(PF_IUCV);
2468 
2469 

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