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.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)
128 struct sk_buff_head *list = &sk->sk_receive_queue;
129 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
131 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
132 (unsigned int)sk->sk_rcvbuf && rx_flow_is_on(cf_sk)) {
133 net_dbg_ratelimited("sending flow OFF (queue len = %d %d)\n",
134 atomic_read(&cf_sk->sk.sk_rmem_alloc),
135 sk_rcvbuf_lowwater(cf_sk));
136 set_rx_flow_off(cf_sk);
137 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
140 err = sk_filter(sk, skb);
143 if (!sk_rmem_schedule(sk, skb, skb->truesize) && rx_flow_is_on(cf_sk)) {
144 set_rx_flow_off(cf_sk);
145 net_dbg_ratelimited("sending flow OFF due to rmem_schedule\n");
146 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
149 skb_set_owner_r(skb, sk);
150 /* Cache the SKB length before we tack it onto the receive
151 * queue. Once it is added it no longer belongs to us and
152 * may be freed by other threads of control pulling packets
155 spin_lock_irqsave(&list->lock, flags);
156 if (!sock_flag(sk, SOCK_DEAD))
157 __skb_queue_tail(list, skb);
158 spin_unlock_irqrestore(&list->lock, flags);
160 if (!sock_flag(sk, SOCK_DEAD))
161 sk->sk_data_ready(sk);
167 /* Packet Receive Callback function called from CAIF Stack */
168 static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt)
170 struct caifsock *cf_sk;
173 cf_sk = container_of(layr, struct caifsock, layer);
174 skb = cfpkt_tonative(pkt);
176 if (unlikely(cf_sk->sk.sk_state != CAIF_CONNECTED)) {
180 caif_queue_rcv_skb(&cf_sk->sk, skb);
184 static void cfsk_hold(struct cflayer *layr)
186 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
187 sock_hold(&cf_sk->sk);
190 static void cfsk_put(struct cflayer *layr)
192 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
193 sock_put(&cf_sk->sk);
196 /* Packet Control Callback function called from CAIF */
197 static void caif_ctrl_cb(struct cflayer *layr,
198 enum caif_ctrlcmd flow,
201 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
203 case CAIF_CTRLCMD_FLOW_ON_IND:
204 /* OK from modem to start sending again */
205 set_tx_flow_on(cf_sk);
206 cf_sk->sk.sk_state_change(&cf_sk->sk);
209 case CAIF_CTRLCMD_FLOW_OFF_IND:
210 /* Modem asks us to shut up */
211 set_tx_flow_off(cf_sk);
212 cf_sk->sk.sk_state_change(&cf_sk->sk);
215 case CAIF_CTRLCMD_INIT_RSP:
216 /* We're now connected */
217 caif_client_register_refcnt(&cf_sk->layer,
218 cfsk_hold, cfsk_put);
219 cf_sk->sk.sk_state = CAIF_CONNECTED;
220 set_tx_flow_on(cf_sk);
221 cf_sk->sk.sk_shutdown = 0;
222 cf_sk->sk.sk_state_change(&cf_sk->sk);
225 case CAIF_CTRLCMD_DEINIT_RSP:
226 /* We're now disconnected */
227 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
228 cf_sk->sk.sk_state_change(&cf_sk->sk);
231 case CAIF_CTRLCMD_INIT_FAIL_RSP:
232 /* Connect request failed */
233 cf_sk->sk.sk_err = ECONNREFUSED;
234 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
235 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
237 * Socket "standards" seems to require POLLOUT to
238 * be set at connect failure.
240 set_tx_flow_on(cf_sk);
241 cf_sk->sk.sk_state_change(&cf_sk->sk);
244 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
245 /* Modem has closed this connection, or device is down. */
246 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
247 cf_sk->sk.sk_err = ECONNRESET;
248 set_rx_flow_on(cf_sk);
249 cf_sk->sk.sk_error_report(&cf_sk->sk);
253 pr_debug("Unexpected flow command %d\n", flow);
257 static void caif_check_flow_release(struct sock *sk)
259 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
261 if (rx_flow_is_on(cf_sk))
264 if (atomic_read(&sk->sk_rmem_alloc) <= sk_rcvbuf_lowwater(cf_sk)) {
265 set_rx_flow_on(cf_sk);
266 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_ON_REQ);
271 * Copied from unix_dgram_recvmsg, but removed credit checks,
272 * changed locking, address handling and added MSG_TRUNC.
274 static int caif_seqpkt_recvmsg(struct socket *sock, struct msghdr *m,
275 size_t len, int flags)
278 struct sock *sk = sock->sk;
287 skb = skb_recv_datagram(sk, flags, 0 , &ret);
292 m->msg_flags |= MSG_TRUNC;
296 ret = skb_copy_datagram_msg(skb, 0, m, copylen);
300 ret = (flags & MSG_TRUNC) ? skb->len : copylen;
302 skb_free_datagram(sk, skb);
303 caif_check_flow_release(sk);
311 /* Copied from unix_stream_wait_data, identical except for lock call. */
312 static long caif_stream_data_wait(struct sock *sk, long timeo)
318 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
320 if (!skb_queue_empty(&sk->sk_receive_queue) ||
322 sk->sk_state != CAIF_CONNECTED ||
323 sock_flag(sk, SOCK_DEAD) ||
324 (sk->sk_shutdown & RCV_SHUTDOWN) ||
325 signal_pending(current) ||
329 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
331 timeo = schedule_timeout(timeo);
333 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
336 finish_wait(sk_sleep(sk), &wait);
343 * Copied from unix_stream_recvmsg, but removed credit checks,
344 * changed locking calls, changed address handling.
346 static int caif_stream_recvmsg(struct socket *sock, struct msghdr *msg,
347 size_t size, int flags)
349 struct sock *sk = sock->sk;
360 * Lock the socket to prevent queue disordering
361 * while sleeps in memcpy_tomsg
364 if (sk->sk_state == CAIF_CONNECTING)
368 target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
369 timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
376 skb = skb_dequeue(&sk->sk_receive_queue);
377 caif_check_flow_release(sk);
380 if (copied >= target)
383 * POSIX 1003.1g mandates this order.
385 err = sock_error(sk);
389 if (sk->sk_shutdown & RCV_SHUTDOWN)
393 if (sk->sk_state != CAIF_CONNECTED)
395 if (sock_flag(sk, SOCK_DEAD))
404 caif_read_unlock(sk);
406 timeo = caif_stream_data_wait(sk, timeo);
408 if (signal_pending(current)) {
409 err = sock_intr_errno(timeo);
419 chunk = min_t(unsigned int, skb->len, size);
420 if (memcpy_to_msg(msg, skb->data, chunk)) {
421 skb_queue_head(&sk->sk_receive_queue, skb);
429 /* Mark read part of skb as used */
430 if (!(flags & MSG_PEEK)) {
431 skb_pull(skb, chunk);
433 /* put the skb back if we didn't use it up. */
435 skb_queue_head(&sk->sk_receive_queue, skb);
442 * It is questionable, see note in unix_dgram_recvmsg.
444 /* put message back and return */
445 skb_queue_head(&sk->sk_receive_queue, skb);
449 caif_read_unlock(sk);
452 return copied ? : err;
456 * Copied from sock.c:sock_wait_for_wmem, but change to wait for
457 * CAIF flow-on and sock_writable.
459 static long caif_wait_for_flow_on(struct caifsock *cf_sk,
460 int wait_writeable, long timeo, int *err)
462 struct sock *sk = &cf_sk->sk;
466 if (tx_flow_is_on(cf_sk) &&
467 (!wait_writeable || sock_writeable(&cf_sk->sk)))
473 if (signal_pending(current))
475 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
477 if (sk->sk_shutdown & SHUTDOWN_MASK)
483 if (cf_sk->sk.sk_state != CAIF_CONNECTED)
485 timeo = schedule_timeout(timeo);
487 finish_wait(sk_sleep(sk), &wait);
492 * Transmit a SKB. The device may temporarily request re-transmission
493 * by returning EAGAIN.
495 static int transmit_skb(struct sk_buff *skb, struct caifsock *cf_sk,
496 int noblock, long timeo)
500 pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
501 memset(skb->cb, 0, sizeof(struct caif_payload_info));
502 cfpkt_set_prio(pkt, cf_sk->sk.sk_priority);
504 if (cf_sk->layer.dn == NULL) {
509 return cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
512 /* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
513 static int caif_seqpkt_sendmsg(struct socket *sock, struct msghdr *msg,
516 struct sock *sk = sock->sk;
517 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
520 struct sk_buff *skb = NULL;
524 ret = sock_error(sk);
529 if (msg->msg_flags&MSG_OOB)
533 if (msg->msg_namelen)
537 if (unlikely(msg->msg_iter.iov->iov_base == NULL))
539 noblock = msg->msg_flags & MSG_DONTWAIT;
541 timeo = sock_sndtimeo(sk, noblock);
542 timeo = caif_wait_for_flow_on(container_of(sk, struct caifsock, sk),
548 if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
549 sock_flag(sk, SOCK_DEAD) ||
550 (sk->sk_shutdown & RCV_SHUTDOWN))
553 /* Error if trying to write more than maximum frame size. */
555 if (len > cf_sk->maxframe && cf_sk->sk.sk_protocol != CAIFPROTO_RFM)
558 buffer_size = len + cf_sk->headroom + cf_sk->tailroom;
561 skb = sock_alloc_send_skb(sk, buffer_size, noblock, &ret);
563 if (!skb || skb_tailroom(skb) < buffer_size)
566 skb_reserve(skb, cf_sk->headroom);
568 ret = memcpy_from_msg(skb_put(skb, len), msg, len);
572 ret = transmit_skb(skb, cf_sk, noblock, timeo);
574 /* skb is already freed */
584 * Copied from unix_stream_sendmsg and adapted to CAIF:
585 * Changed removed permission handling and added waiting for flow on
586 * and other minor adaptations.
588 static int caif_stream_sendmsg(struct socket *sock, struct msghdr *msg,
591 struct sock *sk = sock->sk;
592 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
599 if (unlikely(msg->msg_flags&MSG_OOB))
602 if (unlikely(msg->msg_namelen))
605 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
606 timeo = caif_wait_for_flow_on(cf_sk, 1, timeo, &err);
608 if (unlikely(sk->sk_shutdown & SEND_SHUTDOWN))
615 if (size > cf_sk->maxframe)
616 size = cf_sk->maxframe;
618 /* If size is more than half of sndbuf, chop up message */
619 if (size > ((sk->sk_sndbuf >> 1) - 64))
620 size = (sk->sk_sndbuf >> 1) - 64;
622 if (size > SKB_MAX_ALLOC)
623 size = SKB_MAX_ALLOC;
625 skb = sock_alloc_send_skb(sk,
626 size + cf_sk->headroom +
628 msg->msg_flags&MSG_DONTWAIT,
633 skb_reserve(skb, cf_sk->headroom);
635 * If you pass two values to the sock_alloc_send_skb
636 * it tries to grab the large buffer with GFP_NOFS
637 * (which can fail easily), and if it fails grab the
638 * fallback size buffer which is under a page and will
641 size = min_t(int, size, skb_tailroom(skb));
643 err = memcpy_from_msg(skb_put(skb, size), msg, size);
648 err = transmit_skb(skb, cf_sk,
649 msg->msg_flags&MSG_DONTWAIT, timeo);
651 /* skb is already freed */
660 if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL))
661 send_sig(SIGPIPE, current, 0);
667 static int setsockopt(struct socket *sock,
668 int lvl, int opt, char __user *ov, unsigned int ol)
670 struct sock *sk = sock->sk;
671 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
674 if (cf_sk->sk.sk_socket->state != SS_UNCONNECTED)
678 case CAIFSO_LINK_SELECT:
679 if (ol < sizeof(int))
683 if (copy_from_user(&linksel, ov, sizeof(int)))
685 lock_sock(&(cf_sk->sk));
686 cf_sk->conn_req.link_selector = linksel;
687 release_sock(&cf_sk->sk);
690 case CAIFSO_REQ_PARAM:
693 if (cf_sk->sk.sk_protocol != CAIFPROTO_UTIL)
695 lock_sock(&(cf_sk->sk));
696 if (ol > sizeof(cf_sk->conn_req.param.data) ||
697 copy_from_user(&cf_sk->conn_req.param.data, ov, ol)) {
698 release_sock(&cf_sk->sk);
701 cf_sk->conn_req.param.size = ol;
702 release_sock(&cf_sk->sk);
716 * caif_connect() - Connect a CAIF Socket
717 * Copied and modified af_irda.c:irda_connect().
719 * Note : by consulting "errno", the user space caller may learn the cause
720 * of the failure. Most of them are visible in the function, others may come
721 * from subroutines called and are listed here :
722 * o -EAFNOSUPPORT: bad socket family or type.
723 * o -ESOCKTNOSUPPORT: bad socket type or protocol
724 * o -EINVAL: bad socket address, or CAIF link type
725 * o -ECONNREFUSED: remote end refused the connection.
726 * o -EINPROGRESS: connect request sent but timed out (or non-blocking)
727 * o -EISCONN: already connected.
728 * o -ETIMEDOUT: Connection timed out (send timeout)
729 * o -ENODEV: No link layer to send request
730 * o -ECONNRESET: Received Shutdown indication or lost link layer
731 * o -ENOMEM: Out of memory
734 * o sk_state: holds the CAIF_* protocol state, it's updated by
736 * o sock->state: holds the SS_* socket state and is updated by connect and
739 static int caif_connect(struct socket *sock, struct sockaddr *uaddr,
740 int addr_len, int flags)
742 struct sock *sk = sock->sk;
743 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
746 int ifindex, headroom, tailroom;
748 struct net_device *dev;
753 if (uaddr->sa_family != AF_CAIF)
756 switch (sock->state) {
758 /* Normal case, a fresh connect */
759 caif_assert(sk->sk_state == CAIF_DISCONNECTED);
762 switch (sk->sk_state) {
764 sock->state = SS_CONNECTED;
767 case CAIF_DISCONNECTED:
768 /* Reconnect allowed */
770 case CAIF_CONNECTING:
772 if (flags & O_NONBLOCK)
778 caif_assert(sk->sk_state == CAIF_CONNECTED ||
779 sk->sk_state == CAIF_DISCONNECTED);
780 if (sk->sk_shutdown & SHUTDOWN_MASK) {
781 /* Allow re-connect after SHUTDOWN_IND */
782 caif_disconnect_client(sock_net(sk), &cf_sk->layer);
783 caif_free_client(&cf_sk->layer);
786 /* No reconnect on a seqpacket socket */
789 case SS_DISCONNECTING:
791 caif_assert(1); /*Should never happen */
794 sk->sk_state = CAIF_DISCONNECTED;
795 sock->state = SS_UNCONNECTED;
796 sk_stream_kill_queues(&cf_sk->sk);
799 if (addr_len != sizeof(struct sockaddr_caif))
802 memcpy(&cf_sk->conn_req.sockaddr, uaddr,
803 sizeof(struct sockaddr_caif));
805 /* Move to connecting socket, start sending Connect Requests */
806 sock->state = SS_CONNECTING;
807 sk->sk_state = CAIF_CONNECTING;
809 /* Check priority value comming from socket */
810 /* if priority value is out of range it will be ajusted */
811 if (cf_sk->sk.sk_priority > CAIF_PRIO_MAX)
812 cf_sk->conn_req.priority = CAIF_PRIO_MAX;
813 else if (cf_sk->sk.sk_priority < CAIF_PRIO_MIN)
814 cf_sk->conn_req.priority = CAIF_PRIO_MIN;
816 cf_sk->conn_req.priority = cf_sk->sk.sk_priority;
818 /*ifindex = id of the interface.*/
819 cf_sk->conn_req.ifindex = cf_sk->sk.sk_bound_dev_if;
821 cf_sk->layer.receive = caif_sktrecv_cb;
823 err = caif_connect_client(sock_net(sk), &cf_sk->conn_req,
824 &cf_sk->layer, &ifindex, &headroom, &tailroom);
827 cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
828 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
834 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
839 cf_sk->headroom = LL_RESERVED_SPACE_EXTRA(dev, headroom);
843 cf_sk->tailroom = tailroom;
844 cf_sk->maxframe = mtu - (headroom + tailroom);
845 if (cf_sk->maxframe < 1) {
846 pr_warn("CAIF Interface MTU too small (%d)\n", dev->mtu);
854 if (sk->sk_state != CAIF_CONNECTED && (flags & O_NONBLOCK))
857 timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
861 timeo = wait_event_interruptible_timeout(*sk_sleep(sk),
862 sk->sk_state != CAIF_CONNECTING,
866 goto out; /* -ERESTARTSYS */
869 if (timeo == 0 && sk->sk_state != CAIF_CONNECTED)
871 if (sk->sk_state != CAIF_CONNECTED) {
872 sock->state = SS_UNCONNECTED;
873 err = sock_error(sk);
878 sock->state = SS_CONNECTED;
886 * caif_release() - Disconnect a CAIF Socket
887 * Copied and modified af_irda.c:irda_release().
889 static int caif_release(struct socket *sock)
891 struct sock *sk = sock->sk;
892 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
897 set_tx_flow_off(cf_sk);
900 * Ensure that packets are not queued after this point in time.
901 * caif_queue_rcv_skb checks SOCK_DEAD holding the queue lock,
902 * this ensures no packets when sock is dead.
904 spin_lock_bh(&sk->sk_receive_queue.lock);
905 sock_set_flag(sk, SOCK_DEAD);
906 spin_unlock_bh(&sk->sk_receive_queue.lock);
909 WARN_ON(IS_ERR(cf_sk->debugfs_socket_dir));
910 debugfs_remove_recursive(cf_sk->debugfs_socket_dir);
912 lock_sock(&(cf_sk->sk));
913 sk->sk_state = CAIF_DISCONNECTED;
914 sk->sk_shutdown = SHUTDOWN_MASK;
916 caif_disconnect_client(sock_net(sk), &cf_sk->layer);
917 cf_sk->sk.sk_socket->state = SS_DISCONNECTING;
918 wake_up_interruptible_poll(sk_sleep(sk), POLLERR|POLLHUP);
921 sk_stream_kill_queues(&cf_sk->sk);
927 /* Copied from af_unix.c:unix_poll(), added CAIF tx_flow handling */
928 static unsigned int caif_poll(struct file *file,
929 struct socket *sock, poll_table *wait)
931 struct sock *sk = sock->sk;
933 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
935 sock_poll_wait(file, sk_sleep(sk), wait);
938 /* exceptional events? */
941 if (sk->sk_shutdown == SHUTDOWN_MASK)
943 if (sk->sk_shutdown & RCV_SHUTDOWN)
947 if (!skb_queue_empty(&sk->sk_receive_queue) ||
948 (sk->sk_shutdown & RCV_SHUTDOWN))
949 mask |= POLLIN | POLLRDNORM;
952 * we set writable also when the other side has shut down the
953 * connection. This prevents stuck sockets.
955 if (sock_writeable(sk) && tx_flow_is_on(cf_sk))
956 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
961 static const struct proto_ops caif_seqpacket_ops = {
963 .owner = THIS_MODULE,
964 .release = caif_release,
965 .bind = sock_no_bind,
966 .connect = caif_connect,
967 .socketpair = sock_no_socketpair,
968 .accept = sock_no_accept,
969 .getname = sock_no_getname,
971 .ioctl = sock_no_ioctl,
972 .listen = sock_no_listen,
973 .shutdown = sock_no_shutdown,
974 .setsockopt = setsockopt,
975 .getsockopt = sock_no_getsockopt,
976 .sendmsg = caif_seqpkt_sendmsg,
977 .recvmsg = caif_seqpkt_recvmsg,
978 .mmap = sock_no_mmap,
979 .sendpage = sock_no_sendpage,
982 static const struct proto_ops caif_stream_ops = {
984 .owner = THIS_MODULE,
985 .release = caif_release,
986 .bind = sock_no_bind,
987 .connect = caif_connect,
988 .socketpair = sock_no_socketpair,
989 .accept = sock_no_accept,
990 .getname = sock_no_getname,
992 .ioctl = sock_no_ioctl,
993 .listen = sock_no_listen,
994 .shutdown = sock_no_shutdown,
995 .setsockopt = setsockopt,
996 .getsockopt = sock_no_getsockopt,
997 .sendmsg = caif_stream_sendmsg,
998 .recvmsg = caif_stream_recvmsg,
999 .mmap = sock_no_mmap,
1000 .sendpage = sock_no_sendpage,
1003 /* This function is called when a socket is finally destroyed. */
1004 static void caif_sock_destructor(struct sock *sk)
1006 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
1007 caif_assert(!atomic_read(&sk->sk_wmem_alloc));
1008 caif_assert(sk_unhashed(sk));
1009 caif_assert(!sk->sk_socket);
1010 if (!sock_flag(sk, SOCK_DEAD)) {
1011 pr_debug("Attempt to release alive CAIF socket: %p\n", sk);
1014 sk_stream_kill_queues(&cf_sk->sk);
1015 caif_free_client(&cf_sk->layer);
1018 static int caif_create(struct net *net, struct socket *sock, int protocol,
1021 struct sock *sk = NULL;
1022 struct caifsock *cf_sk = NULL;
1023 static struct proto prot = {.name = "PF_CAIF",
1024 .owner = THIS_MODULE,
1025 .obj_size = sizeof(struct caifsock),
1028 if (!capable(CAP_SYS_ADMIN) && !capable(CAP_NET_ADMIN))
1031 * The sock->type specifies the socket type to use.
1032 * The CAIF socket is a packet stream in the sense
1033 * that it is packet based. CAIF trusts the reliability
1034 * of the link, no resending is implemented.
1036 if (sock->type == SOCK_SEQPACKET)
1037 sock->ops = &caif_seqpacket_ops;
1038 else if (sock->type == SOCK_STREAM)
1039 sock->ops = &caif_stream_ops;
1041 return -ESOCKTNOSUPPORT;
1043 if (protocol < 0 || protocol >= CAIFPROTO_MAX)
1044 return -EPROTONOSUPPORT;
1046 * Set the socket state to unconnected. The socket state
1047 * is really not used at all in the net/core or socket.c but the
1048 * initialization makes sure that sock->state is not uninitialized.
1050 sk = sk_alloc(net, PF_CAIF, GFP_KERNEL, &prot);
1054 cf_sk = container_of(sk, struct caifsock, sk);
1056 /* Store the protocol */
1057 sk->sk_protocol = (unsigned char) protocol;
1059 /* Initialize default priority for well-known cases */
1062 sk->sk_priority = TC_PRIO_CONTROL;
1065 sk->sk_priority = TC_PRIO_INTERACTIVE_BULK;
1068 sk->sk_priority = TC_PRIO_BESTEFFORT;
1072 * Lock in order to try to stop someone from opening the socket
1075 lock_sock(&(cf_sk->sk));
1077 /* Initialize the nozero default sock structure data. */
1078 sock_init_data(sock, sk);
1079 sk->sk_destruct = caif_sock_destructor;
1081 mutex_init(&cf_sk->readlock); /* single task reading lock */
1082 cf_sk->layer.ctrlcmd = caif_ctrl_cb;
1083 cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
1084 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
1086 set_tx_flow_off(cf_sk);
1087 set_rx_flow_on(cf_sk);
1089 /* Set default options on configuration */
1090 cf_sk->conn_req.link_selector = CAIF_LINK_LOW_LATENCY;
1091 cf_sk->conn_req.protocol = protocol;
1092 release_sock(&cf_sk->sk);
1097 static struct net_proto_family caif_family_ops = {
1099 .create = caif_create,
1100 .owner = THIS_MODULE,
1103 static int __init caif_sktinit_module(void)
1105 int err = sock_register(&caif_family_ops);
1111 static void __exit caif_sktexit_module(void)
1113 sock_unregister(PF_CAIF);
1115 module_init(caif_sktinit_module);
1116 module_exit(caif_sktexit_module);