2 * Copyright (C) ST-Ericsson AB 2010
3 * Author: Sjur Brendeland sjur.brandeland@stericsson.com
4 * License terms: GNU General Public License (GPL) version 2
7 #define pr_fmt(fmt) KBUILD_MODNAME ":%s(): " fmt, __func__
10 #include <linux/init.h>
11 #include <linux/module.h>
12 #include <linux/sched.h>
13 #include <linux/spinlock.h>
14 #include <linux/mutex.h>
15 #include <linux/list.h>
16 #include <linux/wait.h>
17 #include <linux/poll.h>
18 #include <linux/tcp.h>
19 #include <linux/uaccess.h>
20 #include <linux/debugfs.h>
21 #include <linux/caif/caif_socket.h>
22 #include <linux/pkt_sched.h>
24 #include <net/tcp_states.h>
25 #include <net/caif/caif_layer.h>
26 #include <net/caif/caif_dev.h>
27 #include <net/caif/cfpkt.h>
29 MODULE_LICENSE("GPL");
30 MODULE_ALIAS_NETPROTO(AF_CAIF);
33 * CAIF state is re-using the TCP socket states.
34 * caif_states stored in sk_state reflect the state as reported by
35 * the CAIF stack, while sk_socket->state is the state of the socket.
38 CAIF_CONNECTED = TCP_ESTABLISHED,
39 CAIF_CONNECTING = TCP_SYN_SENT,
40 CAIF_DISCONNECTED = TCP_CLOSE
43 #define TX_FLOW_ON_BIT 1
44 #define RX_FLOW_ON_BIT 2
47 struct sock sk; /* must be first member */
50 struct caif_connect_request conn_req;
51 struct mutex readlock;
52 struct dentry *debugfs_socket_dir;
53 int headroom, tailroom, maxframe;
56 static int rx_flow_is_on(struct caifsock *cf_sk)
58 return test_bit(RX_FLOW_ON_BIT,
59 (void *) &cf_sk->flow_state);
62 static int tx_flow_is_on(struct caifsock *cf_sk)
64 return test_bit(TX_FLOW_ON_BIT,
65 (void *) &cf_sk->flow_state);
68 static void set_rx_flow_off(struct caifsock *cf_sk)
70 clear_bit(RX_FLOW_ON_BIT,
71 (void *) &cf_sk->flow_state);
74 static void set_rx_flow_on(struct caifsock *cf_sk)
76 set_bit(RX_FLOW_ON_BIT,
77 (void *) &cf_sk->flow_state);
80 static void set_tx_flow_off(struct caifsock *cf_sk)
82 clear_bit(TX_FLOW_ON_BIT,
83 (void *) &cf_sk->flow_state);
86 static void set_tx_flow_on(struct caifsock *cf_sk)
88 set_bit(TX_FLOW_ON_BIT,
89 (void *) &cf_sk->flow_state);
92 static void caif_read_lock(struct sock *sk)
94 struct caifsock *cf_sk;
95 cf_sk = container_of(sk, struct caifsock, sk);
96 mutex_lock(&cf_sk->readlock);
99 static void caif_read_unlock(struct sock *sk)
101 struct caifsock *cf_sk;
102 cf_sk = container_of(sk, struct caifsock, sk);
103 mutex_unlock(&cf_sk->readlock);
106 static int sk_rcvbuf_lowwater(struct caifsock *cf_sk)
108 /* A quarter of full buffer is used a low water mark */
109 return cf_sk->sk.sk_rcvbuf / 4;
112 static void caif_flow_ctrl(struct sock *sk, int mode)
114 struct caifsock *cf_sk;
115 cf_sk = container_of(sk, struct caifsock, sk);
116 if (cf_sk->layer.dn && cf_sk->layer.dn->modemcmd)
117 cf_sk->layer.dn->modemcmd(cf_sk->layer.dn, mode);
121 * Copied from sock.c:sock_queue_rcv_skb(), but changed so packets are
122 * not dropped, but CAIF is sending flow off instead.
124 static int caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
129 struct sk_buff_head *list = &sk->sk_receive_queue;
130 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
132 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
133 (unsigned int)sk->sk_rcvbuf && rx_flow_is_on(cf_sk)) {
135 pr_debug("sending flow OFF (queue len = %d %d)\n",
136 atomic_read(&cf_sk->sk.sk_rmem_alloc),
137 sk_rcvbuf_lowwater(cf_sk));
138 set_rx_flow_off(cf_sk);
139 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
142 err = sk_filter(sk, skb);
145 if (!sk_rmem_schedule(sk, skb->truesize) && rx_flow_is_on(cf_sk)) {
146 set_rx_flow_off(cf_sk);
148 pr_debug("sending flow OFF due to rmem_schedule\n");
149 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
152 skb_set_owner_r(skb, sk);
153 /* Cache the SKB length before we tack it onto the receive
154 * queue. Once it is added it no longer belongs to us and
155 * may be freed by other threads of control pulling packets
159 spin_lock_irqsave(&list->lock, flags);
160 if (!sock_flag(sk, SOCK_DEAD))
161 __skb_queue_tail(list, skb);
162 spin_unlock_irqrestore(&list->lock, flags);
164 if (!sock_flag(sk, SOCK_DEAD))
165 sk->sk_data_ready(sk, skb_len);
171 /* Packet Receive Callback function called from CAIF Stack */
172 static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt)
174 struct caifsock *cf_sk;
177 cf_sk = container_of(layr, struct caifsock, layer);
178 skb = cfpkt_tonative(pkt);
180 if (unlikely(cf_sk->sk.sk_state != CAIF_CONNECTED)) {
184 caif_queue_rcv_skb(&cf_sk->sk, skb);
188 static void cfsk_hold(struct cflayer *layr)
190 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
191 sock_hold(&cf_sk->sk);
194 static void cfsk_put(struct cflayer *layr)
196 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
197 sock_put(&cf_sk->sk);
200 /* Packet Control Callback function called from CAIF */
201 static void caif_ctrl_cb(struct cflayer *layr,
202 enum caif_ctrlcmd flow,
205 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
207 case CAIF_CTRLCMD_FLOW_ON_IND:
208 /* OK from modem to start sending again */
209 set_tx_flow_on(cf_sk);
210 cf_sk->sk.sk_state_change(&cf_sk->sk);
213 case CAIF_CTRLCMD_FLOW_OFF_IND:
214 /* Modem asks us to shut up */
215 set_tx_flow_off(cf_sk);
216 cf_sk->sk.sk_state_change(&cf_sk->sk);
219 case CAIF_CTRLCMD_INIT_RSP:
220 /* We're now connected */
221 caif_client_register_refcnt(&cf_sk->layer,
222 cfsk_hold, cfsk_put);
223 cf_sk->sk.sk_state = CAIF_CONNECTED;
224 set_tx_flow_on(cf_sk);
225 cf_sk->sk.sk_state_change(&cf_sk->sk);
228 case CAIF_CTRLCMD_DEINIT_RSP:
229 /* We're now disconnected */
230 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
231 cf_sk->sk.sk_state_change(&cf_sk->sk);
234 case CAIF_CTRLCMD_INIT_FAIL_RSP:
235 /* Connect request failed */
236 cf_sk->sk.sk_err = ECONNREFUSED;
237 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
238 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
240 * Socket "standards" seems to require POLLOUT to
241 * be set at connect failure.
243 set_tx_flow_on(cf_sk);
244 cf_sk->sk.sk_state_change(&cf_sk->sk);
247 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
248 /* Modem has closed this connection, or device is down. */
249 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
250 cf_sk->sk.sk_err = ECONNRESET;
251 set_rx_flow_on(cf_sk);
252 cf_sk->sk.sk_error_report(&cf_sk->sk);
256 pr_debug("Unexpected flow command %d\n", flow);
260 static void caif_check_flow_release(struct sock *sk)
262 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
264 if (rx_flow_is_on(cf_sk))
267 if (atomic_read(&sk->sk_rmem_alloc) <= sk_rcvbuf_lowwater(cf_sk)) {
268 set_rx_flow_on(cf_sk);
269 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_ON_REQ);
274 * Copied from unix_dgram_recvmsg, but removed credit checks,
275 * changed locking, address handling and added MSG_TRUNC.
277 static int caif_seqpkt_recvmsg(struct kiocb *iocb, struct socket *sock,
278 struct msghdr *m, size_t len, int flags)
281 struct sock *sk = sock->sk;
287 if (m->msg_flags&MSG_OOB)
290 skb = skb_recv_datagram(sk, flags, 0 , &ret);
295 m->msg_flags |= MSG_TRUNC;
299 ret = skb_copy_datagram_iovec(skb, 0, m->msg_iov, copylen);
303 ret = (flags & MSG_TRUNC) ? skb->len : copylen;
305 skb_free_datagram(sk, skb);
306 caif_check_flow_release(sk);
314 /* Copied from unix_stream_wait_data, identical except for lock call. */
315 static long caif_stream_data_wait(struct sock *sk, long timeo)
321 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
323 if (!skb_queue_empty(&sk->sk_receive_queue) ||
325 sk->sk_state != CAIF_CONNECTED ||
326 sock_flag(sk, SOCK_DEAD) ||
327 (sk->sk_shutdown & RCV_SHUTDOWN) ||
328 signal_pending(current) ||
332 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
334 timeo = schedule_timeout(timeo);
336 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
339 finish_wait(sk_sleep(sk), &wait);
346 * Copied from unix_stream_recvmsg, but removed credit checks,
347 * changed locking calls, changed address handling.
349 static int caif_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
350 struct msghdr *msg, size_t size,
353 struct sock *sk = sock->sk;
363 msg->msg_namelen = 0;
366 * Lock the socket to prevent queue disordering
367 * while sleeps in memcpy_tomsg
370 if (sk->sk_state == CAIF_CONNECTING)
374 target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
375 timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
382 skb = skb_dequeue(&sk->sk_receive_queue);
383 caif_check_flow_release(sk);
386 if (copied >= target)
389 * POSIX 1003.1g mandates this order.
391 err = sock_error(sk);
395 if (sk->sk_shutdown & RCV_SHUTDOWN)
399 if (sk->sk_state != CAIF_CONNECTED)
401 if (sock_flag(sk, SOCK_DEAD))
410 caif_read_unlock(sk);
412 timeo = caif_stream_data_wait(sk, timeo);
414 if (signal_pending(current)) {
415 err = sock_intr_errno(timeo);
425 chunk = min_t(unsigned int, skb->len, size);
426 if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
427 skb_queue_head(&sk->sk_receive_queue, skb);
435 /* Mark read part of skb as used */
436 if (!(flags & MSG_PEEK)) {
437 skb_pull(skb, chunk);
439 /* put the skb back if we didn't use it up. */
441 skb_queue_head(&sk->sk_receive_queue, skb);
448 * It is questionable, see note in unix_dgram_recvmsg.
450 /* put message back and return */
451 skb_queue_head(&sk->sk_receive_queue, skb);
455 caif_read_unlock(sk);
458 return copied ? : err;
462 * Copied from sock.c:sock_wait_for_wmem, but change to wait for
463 * CAIF flow-on and sock_writable.
465 static long caif_wait_for_flow_on(struct caifsock *cf_sk,
466 int wait_writeable, long timeo, int *err)
468 struct sock *sk = &cf_sk->sk;
472 if (tx_flow_is_on(cf_sk) &&
473 (!wait_writeable || sock_writeable(&cf_sk->sk)))
479 if (signal_pending(current))
481 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
483 if (sk->sk_shutdown & SHUTDOWN_MASK)
489 if (cf_sk->sk.sk_state != CAIF_CONNECTED)
491 timeo = schedule_timeout(timeo);
493 finish_wait(sk_sleep(sk), &wait);
498 * Transmit a SKB. The device may temporarily request re-transmission
499 * by returning EAGAIN.
501 static int transmit_skb(struct sk_buff *skb, struct caifsock *cf_sk,
502 int noblock, long timeo)
506 pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
507 memset(skb->cb, 0, sizeof(struct caif_payload_info));
508 cfpkt_set_prio(pkt, cf_sk->sk.sk_priority);
510 if (cf_sk->layer.dn == NULL) {
515 return cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
518 /* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
519 static int caif_seqpkt_sendmsg(struct kiocb *kiocb, struct socket *sock,
520 struct msghdr *msg, size_t len)
522 struct sock *sk = sock->sk;
523 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
526 struct sk_buff *skb = NULL;
530 ret = sock_error(sk);
535 if (msg->msg_flags&MSG_OOB)
539 if (msg->msg_namelen)
543 if (unlikely(msg->msg_iov->iov_base == NULL))
545 noblock = msg->msg_flags & MSG_DONTWAIT;
547 timeo = sock_sndtimeo(sk, noblock);
548 timeo = caif_wait_for_flow_on(container_of(sk, struct caifsock, sk),
554 if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
555 sock_flag(sk, SOCK_DEAD) ||
556 (sk->sk_shutdown & RCV_SHUTDOWN))
559 /* Error if trying to write more than maximum frame size. */
561 if (len > cf_sk->maxframe && cf_sk->sk.sk_protocol != CAIFPROTO_RFM)
564 buffer_size = len + cf_sk->headroom + cf_sk->tailroom;
567 skb = sock_alloc_send_skb(sk, buffer_size, noblock, &ret);
569 if (!skb || skb_tailroom(skb) < buffer_size)
572 skb_reserve(skb, cf_sk->headroom);
574 ret = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
578 ret = transmit_skb(skb, cf_sk, noblock, timeo);
580 /* skb is already freed */
590 * Copied from unix_stream_sendmsg and adapted to CAIF:
591 * Changed removed permission handling and added waiting for flow on
592 * and other minor adaptations.
594 static int caif_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
595 struct msghdr *msg, size_t len)
597 struct sock *sk = sock->sk;
598 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
605 if (unlikely(msg->msg_flags&MSG_OOB))
608 if (unlikely(msg->msg_namelen))
611 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
612 timeo = caif_wait_for_flow_on(cf_sk, 1, timeo, &err);
614 if (unlikely(sk->sk_shutdown & SEND_SHUTDOWN))
621 if (size > cf_sk->maxframe)
622 size = cf_sk->maxframe;
624 /* If size is more than half of sndbuf, chop up message */
625 if (size > ((sk->sk_sndbuf >> 1) - 64))
626 size = (sk->sk_sndbuf >> 1) - 64;
628 if (size > SKB_MAX_ALLOC)
629 size = SKB_MAX_ALLOC;
631 skb = sock_alloc_send_skb(sk,
632 size + cf_sk->headroom +
634 msg->msg_flags&MSG_DONTWAIT,
639 skb_reserve(skb, cf_sk->headroom);
641 * If you pass two values to the sock_alloc_send_skb
642 * it tries to grab the large buffer with GFP_NOFS
643 * (which can fail easily), and if it fails grab the
644 * fallback size buffer which is under a page and will
647 size = min_t(int, size, skb_tailroom(skb));
649 err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
654 err = transmit_skb(skb, cf_sk,
655 msg->msg_flags&MSG_DONTWAIT, timeo);
657 /* skb is already freed */
666 if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL))
667 send_sig(SIGPIPE, current, 0);
673 static int setsockopt(struct socket *sock,
674 int lvl, int opt, char __user *ov, unsigned int ol)
676 struct sock *sk = sock->sk;
677 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
680 if (cf_sk->sk.sk_socket->state != SS_UNCONNECTED)
684 case CAIFSO_LINK_SELECT:
685 if (ol < sizeof(int))
689 if (copy_from_user(&linksel, ov, sizeof(int)))
691 lock_sock(&(cf_sk->sk));
692 cf_sk->conn_req.link_selector = linksel;
693 release_sock(&cf_sk->sk);
696 case CAIFSO_REQ_PARAM:
699 if (cf_sk->sk.sk_protocol != CAIFPROTO_UTIL)
701 lock_sock(&(cf_sk->sk));
702 if (ol > sizeof(cf_sk->conn_req.param.data) ||
703 copy_from_user(&cf_sk->conn_req.param.data, ov, ol)) {
704 release_sock(&cf_sk->sk);
707 cf_sk->conn_req.param.size = ol;
708 release_sock(&cf_sk->sk);
722 * caif_connect() - Connect a CAIF Socket
723 * Copied and modified af_irda.c:irda_connect().
725 * Note : by consulting "errno", the user space caller may learn the cause
726 * of the failure. Most of them are visible in the function, others may come
727 * from subroutines called and are listed here :
728 * o -EAFNOSUPPORT: bad socket family or type.
729 * o -ESOCKTNOSUPPORT: bad socket type or protocol
730 * o -EINVAL: bad socket address, or CAIF link type
731 * o -ECONNREFUSED: remote end refused the connection.
732 * o -EINPROGRESS: connect request sent but timed out (or non-blocking)
733 * o -EISCONN: already connected.
734 * o -ETIMEDOUT: Connection timed out (send timeout)
735 * o -ENODEV: No link layer to send request
736 * o -ECONNRESET: Received Shutdown indication or lost link layer
737 * o -ENOMEM: Out of memory
740 * o sk_state: holds the CAIF_* protocol state, it's updated by
742 * o sock->state: holds the SS_* socket state and is updated by connect and
745 static int caif_connect(struct socket *sock, struct sockaddr *uaddr,
746 int addr_len, int flags)
748 struct sock *sk = sock->sk;
749 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
752 int ifindex, headroom, tailroom;
754 struct net_device *dev;
759 if (uaddr->sa_family != AF_CAIF)
762 switch (sock->state) {
764 /* Normal case, a fresh connect */
765 caif_assert(sk->sk_state == CAIF_DISCONNECTED);
768 switch (sk->sk_state) {
770 sock->state = SS_CONNECTED;
773 case CAIF_DISCONNECTED:
774 /* Reconnect allowed */
776 case CAIF_CONNECTING:
778 if (flags & O_NONBLOCK)
784 caif_assert(sk->sk_state == CAIF_CONNECTED ||
785 sk->sk_state == CAIF_DISCONNECTED);
786 if (sk->sk_shutdown & SHUTDOWN_MASK) {
787 /* Allow re-connect after SHUTDOWN_IND */
788 caif_disconnect_client(sock_net(sk), &cf_sk->layer);
789 caif_free_client(&cf_sk->layer);
792 /* No reconnect on a seqpacket socket */
795 case SS_DISCONNECTING:
797 caif_assert(1); /*Should never happen */
800 sk->sk_state = CAIF_DISCONNECTED;
801 sock->state = SS_UNCONNECTED;
802 sk_stream_kill_queues(&cf_sk->sk);
805 if (addr_len != sizeof(struct sockaddr_caif))
808 memcpy(&cf_sk->conn_req.sockaddr, uaddr,
809 sizeof(struct sockaddr_caif));
811 /* Move to connecting socket, start sending Connect Requests */
812 sock->state = SS_CONNECTING;
813 sk->sk_state = CAIF_CONNECTING;
815 /* Check priority value comming from socket */
816 /* if priority value is out of range it will be ajusted */
817 if (cf_sk->sk.sk_priority > CAIF_PRIO_MAX)
818 cf_sk->conn_req.priority = CAIF_PRIO_MAX;
819 else if (cf_sk->sk.sk_priority < CAIF_PRIO_MIN)
820 cf_sk->conn_req.priority = CAIF_PRIO_MIN;
822 cf_sk->conn_req.priority = cf_sk->sk.sk_priority;
824 /*ifindex = id of the interface.*/
825 cf_sk->conn_req.ifindex = cf_sk->sk.sk_bound_dev_if;
827 cf_sk->layer.receive = caif_sktrecv_cb;
829 err = caif_connect_client(sock_net(sk), &cf_sk->conn_req,
830 &cf_sk->layer, &ifindex, &headroom, &tailroom);
833 cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
834 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
840 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
845 cf_sk->headroom = LL_RESERVED_SPACE_EXTRA(dev, headroom);
849 cf_sk->tailroom = tailroom;
850 cf_sk->maxframe = mtu - (headroom + tailroom);
851 if (cf_sk->maxframe < 1) {
852 pr_warn("CAIF Interface MTU too small (%d)\n", dev->mtu);
860 if (sk->sk_state != CAIF_CONNECTED && (flags & O_NONBLOCK))
863 timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
867 timeo = wait_event_interruptible_timeout(*sk_sleep(sk),
868 sk->sk_state != CAIF_CONNECTING,
872 goto out; /* -ERESTARTSYS */
875 if (timeo == 0 && sk->sk_state != CAIF_CONNECTED)
877 if (sk->sk_state != CAIF_CONNECTED) {
878 sock->state = SS_UNCONNECTED;
879 err = sock_error(sk);
884 sock->state = SS_CONNECTED;
892 * caif_release() - Disconnect a CAIF Socket
893 * Copied and modified af_irda.c:irda_release().
895 static int caif_release(struct socket *sock)
897 struct sock *sk = sock->sk;
898 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
903 set_tx_flow_off(cf_sk);
906 * Ensure that packets are not queued after this point in time.
907 * caif_queue_rcv_skb checks SOCK_DEAD holding the queue lock,
908 * this ensures no packets when sock is dead.
910 spin_lock_bh(&sk->sk_receive_queue.lock);
911 sock_set_flag(sk, SOCK_DEAD);
912 spin_unlock_bh(&sk->sk_receive_queue.lock);
915 WARN_ON(IS_ERR(cf_sk->debugfs_socket_dir));
916 if (cf_sk->debugfs_socket_dir != NULL)
917 debugfs_remove_recursive(cf_sk->debugfs_socket_dir);
919 lock_sock(&(cf_sk->sk));
920 sk->sk_state = CAIF_DISCONNECTED;
921 sk->sk_shutdown = SHUTDOWN_MASK;
923 caif_disconnect_client(sock_net(sk), &cf_sk->layer);
924 cf_sk->sk.sk_socket->state = SS_DISCONNECTING;
925 wake_up_interruptible_poll(sk_sleep(sk), POLLERR|POLLHUP);
928 sk_stream_kill_queues(&cf_sk->sk);
934 /* Copied from af_unix.c:unix_poll(), added CAIF tx_flow handling */
935 static unsigned int caif_poll(struct file *file,
936 struct socket *sock, poll_table *wait)
938 struct sock *sk = sock->sk;
940 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
942 sock_poll_wait(file, sk_sleep(sk), wait);
945 /* exceptional events? */
948 if (sk->sk_shutdown == SHUTDOWN_MASK)
950 if (sk->sk_shutdown & RCV_SHUTDOWN)
954 if (!skb_queue_empty(&sk->sk_receive_queue) ||
955 (sk->sk_shutdown & RCV_SHUTDOWN))
956 mask |= POLLIN | POLLRDNORM;
959 * we set writable also when the other side has shut down the
960 * connection. This prevents stuck sockets.
962 if (sock_writeable(sk) && tx_flow_is_on(cf_sk))
963 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
968 static const struct proto_ops caif_seqpacket_ops = {
970 .owner = THIS_MODULE,
971 .release = caif_release,
972 .bind = sock_no_bind,
973 .connect = caif_connect,
974 .socketpair = sock_no_socketpair,
975 .accept = sock_no_accept,
976 .getname = sock_no_getname,
978 .ioctl = sock_no_ioctl,
979 .listen = sock_no_listen,
980 .shutdown = sock_no_shutdown,
981 .setsockopt = setsockopt,
982 .getsockopt = sock_no_getsockopt,
983 .sendmsg = caif_seqpkt_sendmsg,
984 .recvmsg = caif_seqpkt_recvmsg,
985 .mmap = sock_no_mmap,
986 .sendpage = sock_no_sendpage,
989 static const struct proto_ops caif_stream_ops = {
991 .owner = THIS_MODULE,
992 .release = caif_release,
993 .bind = sock_no_bind,
994 .connect = caif_connect,
995 .socketpair = sock_no_socketpair,
996 .accept = sock_no_accept,
997 .getname = sock_no_getname,
999 .ioctl = sock_no_ioctl,
1000 .listen = sock_no_listen,
1001 .shutdown = sock_no_shutdown,
1002 .setsockopt = setsockopt,
1003 .getsockopt = sock_no_getsockopt,
1004 .sendmsg = caif_stream_sendmsg,
1005 .recvmsg = caif_stream_recvmsg,
1006 .mmap = sock_no_mmap,
1007 .sendpage = sock_no_sendpage,
1010 /* This function is called when a socket is finally destroyed. */
1011 static void caif_sock_destructor(struct sock *sk)
1013 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
1014 caif_assert(!atomic_read(&sk->sk_wmem_alloc));
1015 caif_assert(sk_unhashed(sk));
1016 caif_assert(!sk->sk_socket);
1017 if (!sock_flag(sk, SOCK_DEAD)) {
1018 pr_debug("Attempt to release alive CAIF socket: %p\n", sk);
1021 sk_stream_kill_queues(&cf_sk->sk);
1022 caif_free_client(&cf_sk->layer);
1025 static int caif_create(struct net *net, struct socket *sock, int protocol,
1028 struct sock *sk = NULL;
1029 struct caifsock *cf_sk = NULL;
1030 static struct proto prot = {.name = "PF_CAIF",
1031 .owner = THIS_MODULE,
1032 .obj_size = sizeof(struct caifsock),
1035 if (!capable(CAP_SYS_ADMIN) && !capable(CAP_NET_ADMIN))
1038 * The sock->type specifies the socket type to use.
1039 * The CAIF socket is a packet stream in the sense
1040 * that it is packet based. CAIF trusts the reliability
1041 * of the link, no resending is implemented.
1043 if (sock->type == SOCK_SEQPACKET)
1044 sock->ops = &caif_seqpacket_ops;
1045 else if (sock->type == SOCK_STREAM)
1046 sock->ops = &caif_stream_ops;
1048 return -ESOCKTNOSUPPORT;
1050 if (protocol < 0 || protocol >= CAIFPROTO_MAX)
1051 return -EPROTONOSUPPORT;
1053 * Set the socket state to unconnected. The socket state
1054 * is really not used at all in the net/core or socket.c but the
1055 * initialization makes sure that sock->state is not uninitialized.
1057 sk = sk_alloc(net, PF_CAIF, GFP_KERNEL, &prot);
1061 cf_sk = container_of(sk, struct caifsock, sk);
1063 /* Store the protocol */
1064 sk->sk_protocol = (unsigned char) protocol;
1066 /* Initialize default priority for well-known cases */
1069 sk->sk_priority = TC_PRIO_CONTROL;
1072 sk->sk_priority = TC_PRIO_INTERACTIVE_BULK;
1075 sk->sk_priority = TC_PRIO_BESTEFFORT;
1079 * Lock in order to try to stop someone from opening the socket
1082 lock_sock(&(cf_sk->sk));
1084 /* Initialize the nozero default sock structure data. */
1085 sock_init_data(sock, sk);
1086 sk->sk_destruct = caif_sock_destructor;
1088 mutex_init(&cf_sk->readlock); /* single task reading lock */
1089 cf_sk->layer.ctrlcmd = caif_ctrl_cb;
1090 cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
1091 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
1093 set_tx_flow_off(cf_sk);
1094 set_rx_flow_on(cf_sk);
1096 /* Set default options on configuration */
1097 cf_sk->conn_req.link_selector = CAIF_LINK_LOW_LATENCY;
1098 cf_sk->conn_req.protocol = protocol;
1099 release_sock(&cf_sk->sk);
1104 static struct net_proto_family caif_family_ops = {
1106 .create = caif_create,
1107 .owner = THIS_MODULE,
1110 static int __init caif_sktinit_module(void)
1112 int err = sock_register(&caif_family_ops);
1118 static void __exit caif_sktexit_module(void)
1120 sock_unregister(PF_CAIF);
1122 module_init(caif_sktinit_module);
1123 module_exit(caif_sktexit_module);