2 * Copyright (C) ST-Ericsson AB 2010
3 * Author: Sjur Brendeland
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/signal.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 void caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
128 struct sk_buff_head *list = &sk->sk_receive_queue;
129 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)) {
134 net_dbg_ratelimited("sending flow OFF (queue len = %d %d)\n",
135 atomic_read(&cf_sk->sk.sk_rmem_alloc),
136 sk_rcvbuf_lowwater(cf_sk));
137 set_rx_flow_off(cf_sk);
138 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
141 err = sk_filter(sk, skb);
145 if (!sk_rmem_schedule(sk, skb, skb->truesize) && rx_flow_is_on(cf_sk)) {
146 set_rx_flow_off(cf_sk);
147 net_dbg_ratelimited("sending flow OFF due to rmem_schedule\n");
148 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
151 skb_set_owner_r(skb, sk);
152 spin_lock_irqsave(&list->lock, flags);
153 queued = !sock_flag(sk, SOCK_DEAD);
155 __skb_queue_tail(list, skb);
156 spin_unlock_irqrestore(&list->lock, flags);
159 sk->sk_data_ready(sk);
164 /* Packet Receive Callback function called from CAIF Stack */
165 static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt)
167 struct caifsock *cf_sk;
170 cf_sk = container_of(layr, struct caifsock, layer);
171 skb = cfpkt_tonative(pkt);
173 if (unlikely(cf_sk->sk.sk_state != CAIF_CONNECTED)) {
177 caif_queue_rcv_skb(&cf_sk->sk, skb);
181 static void cfsk_hold(struct cflayer *layr)
183 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
184 sock_hold(&cf_sk->sk);
187 static void cfsk_put(struct cflayer *layr)
189 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
190 sock_put(&cf_sk->sk);
193 /* Packet Control Callback function called from CAIF */
194 static void caif_ctrl_cb(struct cflayer *layr,
195 enum caif_ctrlcmd flow,
198 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
200 case CAIF_CTRLCMD_FLOW_ON_IND:
201 /* OK from modem to start sending again */
202 set_tx_flow_on(cf_sk);
203 cf_sk->sk.sk_state_change(&cf_sk->sk);
206 case CAIF_CTRLCMD_FLOW_OFF_IND:
207 /* Modem asks us to shut up */
208 set_tx_flow_off(cf_sk);
209 cf_sk->sk.sk_state_change(&cf_sk->sk);
212 case CAIF_CTRLCMD_INIT_RSP:
213 /* We're now connected */
214 caif_client_register_refcnt(&cf_sk->layer,
215 cfsk_hold, cfsk_put);
216 cf_sk->sk.sk_state = CAIF_CONNECTED;
217 set_tx_flow_on(cf_sk);
218 cf_sk->sk.sk_shutdown = 0;
219 cf_sk->sk.sk_state_change(&cf_sk->sk);
222 case CAIF_CTRLCMD_DEINIT_RSP:
223 /* We're now disconnected */
224 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
225 cf_sk->sk.sk_state_change(&cf_sk->sk);
228 case CAIF_CTRLCMD_INIT_FAIL_RSP:
229 /* Connect request failed */
230 cf_sk->sk.sk_err = ECONNREFUSED;
231 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
232 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
234 * Socket "standards" seems to require POLLOUT to
235 * be set at connect failure.
237 set_tx_flow_on(cf_sk);
238 cf_sk->sk.sk_state_change(&cf_sk->sk);
241 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
242 /* Modem has closed this connection, or device is down. */
243 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
244 cf_sk->sk.sk_err = ECONNRESET;
245 set_rx_flow_on(cf_sk);
246 cf_sk->sk.sk_error_report(&cf_sk->sk);
250 pr_debug("Unexpected flow command %d\n", flow);
254 static void caif_check_flow_release(struct sock *sk)
256 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
258 if (rx_flow_is_on(cf_sk))
261 if (atomic_read(&sk->sk_rmem_alloc) <= sk_rcvbuf_lowwater(cf_sk)) {
262 set_rx_flow_on(cf_sk);
263 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_ON_REQ);
268 * Copied from unix_dgram_recvmsg, but removed credit checks,
269 * changed locking, address handling and added MSG_TRUNC.
271 static int caif_seqpkt_recvmsg(struct socket *sock, struct msghdr *m,
272 size_t len, int flags)
275 struct sock *sk = sock->sk;
284 skb = skb_recv_datagram(sk, flags, 0 , &ret);
289 m->msg_flags |= MSG_TRUNC;
293 ret = skb_copy_datagram_msg(skb, 0, m, copylen);
297 ret = (flags & MSG_TRUNC) ? skb->len : copylen;
299 skb_free_datagram(sk, skb);
300 caif_check_flow_release(sk);
308 /* Copied from unix_stream_wait_data, identical except for lock call. */
309 static long caif_stream_data_wait(struct sock *sk, long timeo)
315 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
317 if (!skb_queue_empty(&sk->sk_receive_queue) ||
319 sk->sk_state != CAIF_CONNECTED ||
320 sock_flag(sk, SOCK_DEAD) ||
321 (sk->sk_shutdown & RCV_SHUTDOWN) ||
322 signal_pending(current) ||
326 sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
328 timeo = schedule_timeout(timeo);
331 if (sock_flag(sk, SOCK_DEAD))
334 sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
337 finish_wait(sk_sleep(sk), &wait);
344 * Copied from unix_stream_recvmsg, but removed credit checks,
345 * changed locking calls, changed address handling.
347 static int caif_stream_recvmsg(struct socket *sock, struct msghdr *msg,
348 size_t size, int flags)
350 struct sock *sk = sock->sk;
361 * Lock the socket to prevent queue disordering
362 * while sleeps in memcpy_tomsg
365 if (sk->sk_state == CAIF_CONNECTING)
369 target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
370 timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
377 if (sock_flag(sk, SOCK_DEAD)) {
381 skb = skb_dequeue(&sk->sk_receive_queue);
382 caif_check_flow_release(sk);
385 if (copied >= target)
388 * POSIX 1003.1g mandates this order.
390 err = sock_error(sk);
394 if (sk->sk_shutdown & RCV_SHUTDOWN)
398 if (sk->sk_state != CAIF_CONNECTED)
400 if (sock_flag(sk, SOCK_DEAD))
409 caif_read_unlock(sk);
411 timeo = caif_stream_data_wait(sk, timeo);
413 if (signal_pending(current)) {
414 err = sock_intr_errno(timeo);
424 chunk = min_t(unsigned int, skb->len, size);
425 if (memcpy_to_msg(msg, skb->data, chunk)) {
426 skb_queue_head(&sk->sk_receive_queue, skb);
434 /* Mark read part of skb as used */
435 if (!(flags & MSG_PEEK)) {
436 skb_pull(skb, chunk);
438 /* put the skb back if we didn't use it up. */
440 skb_queue_head(&sk->sk_receive_queue, skb);
447 * It is questionable, see note in unix_dgram_recvmsg.
449 /* put message back and return */
450 skb_queue_head(&sk->sk_receive_queue, skb);
454 caif_read_unlock(sk);
457 return copied ? : err;
461 * Copied from sock.c:sock_wait_for_wmem, but change to wait for
462 * CAIF flow-on and sock_writable.
464 static long caif_wait_for_flow_on(struct caifsock *cf_sk,
465 int wait_writeable, long timeo, int *err)
467 struct sock *sk = &cf_sk->sk;
471 if (tx_flow_is_on(cf_sk) &&
472 (!wait_writeable || sock_writeable(&cf_sk->sk)))
478 if (signal_pending(current))
480 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
482 if (sk->sk_shutdown & SHUTDOWN_MASK)
488 if (cf_sk->sk.sk_state != CAIF_CONNECTED)
490 timeo = schedule_timeout(timeo);
492 finish_wait(sk_sleep(sk), &wait);
497 * Transmit a SKB. The device may temporarily request re-transmission
498 * by returning EAGAIN.
500 static int transmit_skb(struct sk_buff *skb, struct caifsock *cf_sk,
501 int noblock, long timeo)
505 pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
506 memset(skb->cb, 0, sizeof(struct caif_payload_info));
507 cfpkt_set_prio(pkt, cf_sk->sk.sk_priority);
509 if (cf_sk->layer.dn == NULL) {
514 return cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
517 /* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
518 static int caif_seqpkt_sendmsg(struct socket *sock, struct msghdr *msg,
521 struct sock *sk = sock->sk;
522 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
525 struct sk_buff *skb = NULL;
529 ret = sock_error(sk);
534 if (msg->msg_flags&MSG_OOB)
538 if (msg->msg_namelen)
542 if (unlikely(msg->msg_iter.nr_segs == 0) ||
543 unlikely(msg->msg_iter.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_from_msg(skb_put(skb, len), msg, 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 socket *sock, struct msghdr *msg,
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_from_msg(skb_put(skb, size), msg, 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 (addr_len < offsetofend(struct sockaddr, sa_family))
763 if (uaddr->sa_family != AF_CAIF)
766 switch (sock->state) {
768 /* Normal case, a fresh connect */
769 caif_assert(sk->sk_state == CAIF_DISCONNECTED);
772 switch (sk->sk_state) {
774 sock->state = SS_CONNECTED;
777 case CAIF_DISCONNECTED:
778 /* Reconnect allowed */
780 case CAIF_CONNECTING:
782 if (flags & O_NONBLOCK)
788 caif_assert(sk->sk_state == CAIF_CONNECTED ||
789 sk->sk_state == CAIF_DISCONNECTED);
790 if (sk->sk_shutdown & SHUTDOWN_MASK) {
791 /* Allow re-connect after SHUTDOWN_IND */
792 caif_disconnect_client(sock_net(sk), &cf_sk->layer);
793 caif_free_client(&cf_sk->layer);
796 /* No reconnect on a seqpacket socket */
799 case SS_DISCONNECTING:
801 caif_assert(1); /*Should never happen */
804 sk->sk_state = CAIF_DISCONNECTED;
805 sock->state = SS_UNCONNECTED;
806 sk_stream_kill_queues(&cf_sk->sk);
809 if (addr_len != sizeof(struct sockaddr_caif))
812 memcpy(&cf_sk->conn_req.sockaddr, uaddr,
813 sizeof(struct sockaddr_caif));
815 /* Move to connecting socket, start sending Connect Requests */
816 sock->state = SS_CONNECTING;
817 sk->sk_state = CAIF_CONNECTING;
819 /* Check priority value comming from socket */
820 /* if priority value is out of range it will be ajusted */
821 if (cf_sk->sk.sk_priority > CAIF_PRIO_MAX)
822 cf_sk->conn_req.priority = CAIF_PRIO_MAX;
823 else if (cf_sk->sk.sk_priority < CAIF_PRIO_MIN)
824 cf_sk->conn_req.priority = CAIF_PRIO_MIN;
826 cf_sk->conn_req.priority = cf_sk->sk.sk_priority;
828 /*ifindex = id of the interface.*/
829 cf_sk->conn_req.ifindex = cf_sk->sk.sk_bound_dev_if;
831 cf_sk->layer.receive = caif_sktrecv_cb;
833 err = caif_connect_client(sock_net(sk), &cf_sk->conn_req,
834 &cf_sk->layer, &ifindex, &headroom, &tailroom);
837 cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
838 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
844 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
849 cf_sk->headroom = LL_RESERVED_SPACE_EXTRA(dev, headroom);
853 cf_sk->tailroom = tailroom;
854 cf_sk->maxframe = mtu - (headroom + tailroom);
855 if (cf_sk->maxframe < 1) {
856 pr_warn("CAIF Interface MTU too small (%d)\n", dev->mtu);
864 if (sk->sk_state != CAIF_CONNECTED && (flags & O_NONBLOCK))
867 timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
871 timeo = wait_event_interruptible_timeout(*sk_sleep(sk),
872 sk->sk_state != CAIF_CONNECTING,
876 goto out; /* -ERESTARTSYS */
879 if (timeo == 0 && sk->sk_state != CAIF_CONNECTED)
881 if (sk->sk_state != CAIF_CONNECTED) {
882 sock->state = SS_UNCONNECTED;
883 err = sock_error(sk);
888 sock->state = SS_CONNECTED;
896 * caif_release() - Disconnect a CAIF Socket
897 * Copied and modified af_irda.c:irda_release().
899 static int caif_release(struct socket *sock)
901 struct sock *sk = sock->sk;
902 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
907 set_tx_flow_off(cf_sk);
910 * Ensure that packets are not queued after this point in time.
911 * caif_queue_rcv_skb checks SOCK_DEAD holding the queue lock,
912 * this ensures no packets when sock is dead.
914 spin_lock_bh(&sk->sk_receive_queue.lock);
915 sock_set_flag(sk, SOCK_DEAD);
916 spin_unlock_bh(&sk->sk_receive_queue.lock);
919 WARN_ON(IS_ERR(cf_sk->debugfs_socket_dir));
920 debugfs_remove_recursive(cf_sk->debugfs_socket_dir);
922 lock_sock(&(cf_sk->sk));
923 sk->sk_state = CAIF_DISCONNECTED;
924 sk->sk_shutdown = SHUTDOWN_MASK;
926 caif_disconnect_client(sock_net(sk), &cf_sk->layer);
927 cf_sk->sk.sk_socket->state = SS_DISCONNECTING;
928 wake_up_interruptible_poll(sk_sleep(sk), POLLERR|POLLHUP);
931 sk_stream_kill_queues(&cf_sk->sk);
937 /* Copied from af_unix.c:unix_poll(), added CAIF tx_flow handling */
938 static unsigned int caif_poll(struct file *file,
939 struct socket *sock, poll_table *wait)
941 struct sock *sk = sock->sk;
943 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
945 sock_poll_wait(file, sk_sleep(sk), wait);
948 /* exceptional events? */
951 if (sk->sk_shutdown == SHUTDOWN_MASK)
953 if (sk->sk_shutdown & RCV_SHUTDOWN)
957 if (!skb_queue_empty_lockless(&sk->sk_receive_queue) ||
958 (sk->sk_shutdown & RCV_SHUTDOWN))
959 mask |= POLLIN | POLLRDNORM;
962 * we set writable also when the other side has shut down the
963 * connection. This prevents stuck sockets.
965 if (sock_writeable(sk) && tx_flow_is_on(cf_sk))
966 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
971 static const struct proto_ops caif_seqpacket_ops = {
973 .owner = THIS_MODULE,
974 .release = caif_release,
975 .bind = sock_no_bind,
976 .connect = caif_connect,
977 .socketpair = sock_no_socketpair,
978 .accept = sock_no_accept,
979 .getname = sock_no_getname,
981 .ioctl = sock_no_ioctl,
982 .listen = sock_no_listen,
983 .shutdown = sock_no_shutdown,
984 .setsockopt = setsockopt,
985 .getsockopt = sock_no_getsockopt,
986 .sendmsg = caif_seqpkt_sendmsg,
987 .recvmsg = caif_seqpkt_recvmsg,
988 .mmap = sock_no_mmap,
989 .sendpage = sock_no_sendpage,
992 static const struct proto_ops caif_stream_ops = {
994 .owner = THIS_MODULE,
995 .release = caif_release,
996 .bind = sock_no_bind,
997 .connect = caif_connect,
998 .socketpair = sock_no_socketpair,
999 .accept = sock_no_accept,
1000 .getname = sock_no_getname,
1002 .ioctl = sock_no_ioctl,
1003 .listen = sock_no_listen,
1004 .shutdown = sock_no_shutdown,
1005 .setsockopt = setsockopt,
1006 .getsockopt = sock_no_getsockopt,
1007 .sendmsg = caif_stream_sendmsg,
1008 .recvmsg = caif_stream_recvmsg,
1009 .mmap = sock_no_mmap,
1010 .sendpage = sock_no_sendpage,
1013 /* This function is called when a socket is finally destroyed. */
1014 static void caif_sock_destructor(struct sock *sk)
1016 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
1017 caif_assert(!refcount_read(&sk->sk_wmem_alloc));
1018 caif_assert(sk_unhashed(sk));
1019 caif_assert(!sk->sk_socket);
1020 if (!sock_flag(sk, SOCK_DEAD)) {
1021 pr_debug("Attempt to release alive CAIF socket: %p\n", sk);
1024 sk_stream_kill_queues(&cf_sk->sk);
1025 WARN_ON(sk->sk_forward_alloc);
1026 caif_free_client(&cf_sk->layer);
1029 static int caif_create(struct net *net, struct socket *sock, int protocol,
1032 struct sock *sk = NULL;
1033 struct caifsock *cf_sk = NULL;
1034 static struct proto prot = {.name = "PF_CAIF",
1035 .owner = THIS_MODULE,
1036 .obj_size = sizeof(struct caifsock),
1039 if (!capable(CAP_SYS_ADMIN) && !capable(CAP_NET_ADMIN))
1042 * The sock->type specifies the socket type to use.
1043 * The CAIF socket is a packet stream in the sense
1044 * that it is packet based. CAIF trusts the reliability
1045 * of the link, no resending is implemented.
1047 if (sock->type == SOCK_SEQPACKET)
1048 sock->ops = &caif_seqpacket_ops;
1049 else if (sock->type == SOCK_STREAM)
1050 sock->ops = &caif_stream_ops;
1052 return -ESOCKTNOSUPPORT;
1054 if (protocol < 0 || protocol >= CAIFPROTO_MAX)
1055 return -EPROTONOSUPPORT;
1057 * Set the socket state to unconnected. The socket state
1058 * is really not used at all in the net/core or socket.c but the
1059 * initialization makes sure that sock->state is not uninitialized.
1061 sk = sk_alloc(net, PF_CAIF, GFP_KERNEL, &prot, kern);
1065 cf_sk = container_of(sk, struct caifsock, sk);
1067 /* Store the protocol */
1068 sk->sk_protocol = (unsigned char) protocol;
1070 /* Initialize default priority for well-known cases */
1073 sk->sk_priority = TC_PRIO_CONTROL;
1076 sk->sk_priority = TC_PRIO_INTERACTIVE_BULK;
1079 sk->sk_priority = TC_PRIO_BESTEFFORT;
1083 * Lock in order to try to stop someone from opening the socket
1086 lock_sock(&(cf_sk->sk));
1088 /* Initialize the nozero default sock structure data. */
1089 sock_init_data(sock, sk);
1090 sk->sk_destruct = caif_sock_destructor;
1092 mutex_init(&cf_sk->readlock); /* single task reading lock */
1093 cf_sk->layer.ctrlcmd = caif_ctrl_cb;
1094 cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
1095 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
1097 set_tx_flow_off(cf_sk);
1098 set_rx_flow_on(cf_sk);
1100 /* Set default options on configuration */
1101 cf_sk->conn_req.link_selector = CAIF_LINK_LOW_LATENCY;
1102 cf_sk->conn_req.protocol = protocol;
1103 release_sock(&cf_sk->sk);
1108 static const struct net_proto_family caif_family_ops = {
1110 .create = caif_create,
1111 .owner = THIS_MODULE,
1114 static int __init caif_sktinit_module(void)
1116 return sock_register(&caif_family_ops);
1119 static void __exit caif_sktexit_module(void)
1121 sock_unregister(PF_CAIF);
1123 module_init(caif_sktinit_module);
1124 module_exit(caif_sktexit_module);