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 <asm/atomic.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
46 static struct dentry *debugfsdir;
48 #ifdef CONFIG_DEBUG_FS
49 struct debug_fs_counter {
50 atomic_t caif_nr_socks;
51 atomic_t num_connect_req;
52 atomic_t num_connect_resp;
53 atomic_t num_connect_fail_resp;
54 atomic_t num_disconnect;
55 atomic_t num_remote_shutdown_ind;
56 atomic_t num_tx_flow_off_ind;
57 atomic_t num_tx_flow_on_ind;
58 atomic_t num_rx_flow_off;
59 atomic_t num_rx_flow_on;
61 static struct debug_fs_counter cnt;
62 #define dbfs_atomic_inc(v) atomic_inc(v)
63 #define dbfs_atomic_dec(v) atomic_dec(v)
65 #define dbfs_atomic_inc(v)
66 #define dbfs_atomic_dec(v)
70 struct sock sk; /* must be first member */
72 char name[CAIF_LAYER_NAME_SZ]; /* Used for debugging */
74 struct caif_connect_request conn_req;
75 struct mutex readlock;
76 struct dentry *debugfs_socket_dir;
77 int headroom, tailroom, maxframe;
80 static int rx_flow_is_on(struct caifsock *cf_sk)
82 return test_bit(RX_FLOW_ON_BIT,
83 (void *) &cf_sk->flow_state);
86 static int tx_flow_is_on(struct caifsock *cf_sk)
88 return test_bit(TX_FLOW_ON_BIT,
89 (void *) &cf_sk->flow_state);
92 static void set_rx_flow_off(struct caifsock *cf_sk)
94 clear_bit(RX_FLOW_ON_BIT,
95 (void *) &cf_sk->flow_state);
98 static void set_rx_flow_on(struct caifsock *cf_sk)
100 set_bit(RX_FLOW_ON_BIT,
101 (void *) &cf_sk->flow_state);
104 static void set_tx_flow_off(struct caifsock *cf_sk)
106 clear_bit(TX_FLOW_ON_BIT,
107 (void *) &cf_sk->flow_state);
110 static void set_tx_flow_on(struct caifsock *cf_sk)
112 set_bit(TX_FLOW_ON_BIT,
113 (void *) &cf_sk->flow_state);
116 static void caif_read_lock(struct sock *sk)
118 struct caifsock *cf_sk;
119 cf_sk = container_of(sk, struct caifsock, sk);
120 mutex_lock(&cf_sk->readlock);
123 static void caif_read_unlock(struct sock *sk)
125 struct caifsock *cf_sk;
126 cf_sk = container_of(sk, struct caifsock, sk);
127 mutex_unlock(&cf_sk->readlock);
130 static int sk_rcvbuf_lowwater(struct caifsock *cf_sk)
132 /* A quarter of full buffer is used a low water mark */
133 return cf_sk->sk.sk_rcvbuf / 4;
136 static void caif_flow_ctrl(struct sock *sk, int mode)
138 struct caifsock *cf_sk;
139 cf_sk = container_of(sk, struct caifsock, sk);
140 if (cf_sk->layer.dn && cf_sk->layer.dn->modemcmd)
141 cf_sk->layer.dn->modemcmd(cf_sk->layer.dn, mode);
145 * Copied from sock.c:sock_queue_rcv_skb(), but changed so packets are
146 * not dropped, but CAIF is sending flow off instead.
148 static int caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
153 struct sk_buff_head *list = &sk->sk_receive_queue;
154 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
156 if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
157 (unsigned)sk->sk_rcvbuf && rx_flow_is_on(cf_sk)) {
158 pr_debug("sending flow OFF (queue len = %d %d)\n",
159 atomic_read(&cf_sk->sk.sk_rmem_alloc),
160 sk_rcvbuf_lowwater(cf_sk));
161 set_rx_flow_off(cf_sk);
162 dbfs_atomic_inc(&cnt.num_rx_flow_off);
163 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
166 err = sk_filter(sk, skb);
169 if (!sk_rmem_schedule(sk, skb->truesize) && rx_flow_is_on(cf_sk)) {
170 set_rx_flow_off(cf_sk);
171 pr_debug("sending flow OFF due to rmem_schedule\n");
172 dbfs_atomic_inc(&cnt.num_rx_flow_off);
173 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_OFF_REQ);
176 skb_set_owner_r(skb, sk);
177 /* Cache the SKB length before we tack it onto the receive
178 * queue. Once it is added it no longer belongs to us and
179 * may be freed by other threads of control pulling packets
183 spin_lock_irqsave(&list->lock, flags);
184 if (!sock_flag(sk, SOCK_DEAD))
185 __skb_queue_tail(list, skb);
186 spin_unlock_irqrestore(&list->lock, flags);
188 if (!sock_flag(sk, SOCK_DEAD))
189 sk->sk_data_ready(sk, skb_len);
195 /* Packet Receive Callback function called from CAIF Stack */
196 static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt)
198 struct caifsock *cf_sk;
201 cf_sk = container_of(layr, struct caifsock, layer);
202 skb = cfpkt_tonative(pkt);
204 if (unlikely(cf_sk->sk.sk_state != CAIF_CONNECTED)) {
208 caif_queue_rcv_skb(&cf_sk->sk, skb);
212 /* Packet Control Callback function called from CAIF */
213 static void caif_ctrl_cb(struct cflayer *layr,
214 enum caif_ctrlcmd flow,
217 struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
219 case CAIF_CTRLCMD_FLOW_ON_IND:
220 /* OK from modem to start sending again */
221 dbfs_atomic_inc(&cnt.num_tx_flow_on_ind);
222 set_tx_flow_on(cf_sk);
223 cf_sk->sk.sk_state_change(&cf_sk->sk);
226 case CAIF_CTRLCMD_FLOW_OFF_IND:
227 /* Modem asks us to shut up */
228 dbfs_atomic_inc(&cnt.num_tx_flow_off_ind);
229 set_tx_flow_off(cf_sk);
230 cf_sk->sk.sk_state_change(&cf_sk->sk);
233 case CAIF_CTRLCMD_INIT_RSP:
234 /* We're now connected */
235 dbfs_atomic_inc(&cnt.num_connect_resp);
236 cf_sk->sk.sk_state = CAIF_CONNECTED;
237 set_tx_flow_on(cf_sk);
238 cf_sk->sk.sk_state_change(&cf_sk->sk);
241 case CAIF_CTRLCMD_DEINIT_RSP:
242 /* We're now disconnected */
243 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
244 cf_sk->sk.sk_state_change(&cf_sk->sk);
245 cfcnfg_release_adap_layer(&cf_sk->layer);
248 case CAIF_CTRLCMD_INIT_FAIL_RSP:
249 /* Connect request failed */
250 dbfs_atomic_inc(&cnt.num_connect_fail_resp);
251 cf_sk->sk.sk_err = ECONNREFUSED;
252 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
253 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
255 * Socket "standards" seems to require POLLOUT to
256 * be set at connect failure.
258 set_tx_flow_on(cf_sk);
259 cf_sk->sk.sk_state_change(&cf_sk->sk);
262 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
263 /* Modem has closed this connection, or device is down. */
264 dbfs_atomic_inc(&cnt.num_remote_shutdown_ind);
265 cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
266 cf_sk->sk.sk_err = ECONNRESET;
267 set_rx_flow_on(cf_sk);
268 cf_sk->sk.sk_error_report(&cf_sk->sk);
272 pr_debug("Unexpected flow command %d\n", flow);
276 static void caif_check_flow_release(struct sock *sk)
278 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
280 if (rx_flow_is_on(cf_sk))
283 if (atomic_read(&sk->sk_rmem_alloc) <= sk_rcvbuf_lowwater(cf_sk)) {
284 dbfs_atomic_inc(&cnt.num_rx_flow_on);
285 set_rx_flow_on(cf_sk);
286 caif_flow_ctrl(sk, CAIF_MODEMCMD_FLOW_ON_REQ);
291 * Copied from unix_dgram_recvmsg, but removed credit checks,
292 * changed locking, address handling and added MSG_TRUNC.
294 static int caif_seqpkt_recvmsg(struct kiocb *iocb, struct socket *sock,
295 struct msghdr *m, size_t len, int flags)
298 struct sock *sk = sock->sk;
304 if (m->msg_flags&MSG_OOB)
307 skb = skb_recv_datagram(sk, flags, 0 , &ret);
312 m->msg_flags |= MSG_TRUNC;
316 ret = skb_copy_datagram_iovec(skb, 0, m->msg_iov, copylen);
320 ret = (flags & MSG_TRUNC) ? skb->len : copylen;
322 skb_free_datagram(sk, skb);
323 caif_check_flow_release(sk);
331 /* Copied from unix_stream_wait_data, identical except for lock call. */
332 static long caif_stream_data_wait(struct sock *sk, long timeo)
338 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
340 if (!skb_queue_empty(&sk->sk_receive_queue) ||
342 sk->sk_state != CAIF_CONNECTED ||
343 sock_flag(sk, SOCK_DEAD) ||
344 (sk->sk_shutdown & RCV_SHUTDOWN) ||
345 signal_pending(current) ||
349 set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
351 timeo = schedule_timeout(timeo);
353 clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
356 finish_wait(sk_sleep(sk), &wait);
363 * Copied from unix_stream_recvmsg, but removed credit checks,
364 * changed locking calls, changed address handling.
366 static int caif_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
367 struct msghdr *msg, size_t size,
370 struct sock *sk = sock->sk;
380 msg->msg_namelen = 0;
383 * Lock the socket to prevent queue disordering
384 * while sleeps in memcpy_tomsg
387 if (sk->sk_state == CAIF_CONNECTING)
391 target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
392 timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
399 skb = skb_dequeue(&sk->sk_receive_queue);
400 caif_check_flow_release(sk);
403 if (copied >= target)
406 * POSIX 1003.1g mandates this order.
408 err = sock_error(sk);
412 if (sk->sk_shutdown & RCV_SHUTDOWN)
416 if (sk->sk_state != CAIF_CONNECTED)
418 if (sock_flag(sk, SOCK_DEAD))
427 caif_read_unlock(sk);
429 timeo = caif_stream_data_wait(sk, timeo);
431 if (signal_pending(current)) {
432 err = sock_intr_errno(timeo);
442 chunk = min_t(unsigned int, skb->len, size);
443 if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
444 skb_queue_head(&sk->sk_receive_queue, skb);
452 /* Mark read part of skb as used */
453 if (!(flags & MSG_PEEK)) {
454 skb_pull(skb, chunk);
456 /* put the skb back if we didn't use it up. */
458 skb_queue_head(&sk->sk_receive_queue, skb);
465 * It is questionable, see note in unix_dgram_recvmsg.
467 /* put message back and return */
468 skb_queue_head(&sk->sk_receive_queue, skb);
472 caif_read_unlock(sk);
475 return copied ? : err;
479 * Copied from sock.c:sock_wait_for_wmem, but change to wait for
480 * CAIF flow-on and sock_writable.
482 static long caif_wait_for_flow_on(struct caifsock *cf_sk,
483 int wait_writeable, long timeo, int *err)
485 struct sock *sk = &cf_sk->sk;
489 if (tx_flow_is_on(cf_sk) &&
490 (!wait_writeable || sock_writeable(&cf_sk->sk)))
496 if (signal_pending(current))
498 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
500 if (sk->sk_shutdown & SHUTDOWN_MASK)
506 if (cf_sk->sk.sk_state != CAIF_CONNECTED)
508 timeo = schedule_timeout(timeo);
510 finish_wait(sk_sleep(sk), &wait);
515 * Transmit a SKB. The device may temporarily request re-transmission
516 * by returning EAGAIN.
518 static int transmit_skb(struct sk_buff *skb, struct caifsock *cf_sk,
519 int noblock, long timeo)
523 pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
524 memset(cfpkt_info(pkt), 0, sizeof(struct caif_payload_info));
526 if (cf_sk->layer.dn == NULL)
529 return cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
532 /* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
533 static int caif_seqpkt_sendmsg(struct kiocb *kiocb, struct socket *sock,
534 struct msghdr *msg, size_t len)
536 struct sock *sk = sock->sk;
537 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
540 struct sk_buff *skb = NULL;
544 ret = sock_error(sk);
549 if (msg->msg_flags&MSG_OOB)
553 if (msg->msg_namelen)
557 if (unlikely(msg->msg_iov->iov_base == NULL))
559 noblock = msg->msg_flags & MSG_DONTWAIT;
561 timeo = sock_sndtimeo(sk, noblock);
562 timeo = caif_wait_for_flow_on(container_of(sk, struct caifsock, sk),
568 if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
569 sock_flag(sk, SOCK_DEAD) ||
570 (sk->sk_shutdown & RCV_SHUTDOWN))
573 /* Error if trying to write more than maximum frame size. */
575 if (len > cf_sk->maxframe && cf_sk->sk.sk_protocol != CAIFPROTO_RFM)
578 buffer_size = len + cf_sk->headroom + cf_sk->tailroom;
581 skb = sock_alloc_send_skb(sk, buffer_size, noblock, &ret);
583 if (!skb || skb_tailroom(skb) < buffer_size)
586 skb_reserve(skb, cf_sk->headroom);
588 ret = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
592 ret = transmit_skb(skb, cf_sk, noblock, timeo);
602 * Copied from unix_stream_sendmsg and adapted to CAIF:
603 * Changed removed permission handling and added waiting for flow on
604 * and other minor adaptations.
606 static int caif_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
607 struct msghdr *msg, size_t len)
609 struct sock *sk = sock->sk;
610 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
617 if (unlikely(msg->msg_flags&MSG_OOB))
620 if (unlikely(msg->msg_namelen))
623 timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
624 timeo = caif_wait_for_flow_on(cf_sk, 1, timeo, &err);
626 if (unlikely(sk->sk_shutdown & SEND_SHUTDOWN))
633 if (size > cf_sk->maxframe)
634 size = cf_sk->maxframe;
636 /* If size is more than half of sndbuf, chop up message */
637 if (size > ((sk->sk_sndbuf >> 1) - 64))
638 size = (sk->sk_sndbuf >> 1) - 64;
640 if (size > SKB_MAX_ALLOC)
641 size = SKB_MAX_ALLOC;
643 skb = sock_alloc_send_skb(sk,
644 size + cf_sk->headroom +
646 msg->msg_flags&MSG_DONTWAIT,
651 skb_reserve(skb, cf_sk->headroom);
653 * If you pass two values to the sock_alloc_send_skb
654 * it tries to grab the large buffer with GFP_NOFS
655 * (which can fail easily), and if it fails grab the
656 * fallback size buffer which is under a page and will
659 size = min_t(int, size, skb_tailroom(skb));
661 err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
666 err = transmit_skb(skb, cf_sk,
667 msg->msg_flags&MSG_DONTWAIT, timeo);
678 if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL))
679 send_sig(SIGPIPE, current, 0);
685 static int setsockopt(struct socket *sock,
686 int lvl, int opt, char __user *ov, unsigned int ol)
688 struct sock *sk = sock->sk;
689 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
692 if (cf_sk->sk.sk_socket->state != SS_UNCONNECTED)
696 case CAIFSO_LINK_SELECT:
697 if (ol < sizeof(int))
701 if (copy_from_user(&linksel, ov, sizeof(int)))
703 lock_sock(&(cf_sk->sk));
704 cf_sk->conn_req.link_selector = linksel;
705 release_sock(&cf_sk->sk);
708 case CAIFSO_REQ_PARAM:
711 if (cf_sk->sk.sk_protocol != CAIFPROTO_UTIL)
713 lock_sock(&(cf_sk->sk));
714 if (ol > sizeof(cf_sk->conn_req.param.data) ||
715 copy_from_user(&cf_sk->conn_req.param.data, ov, ol)) {
716 release_sock(&cf_sk->sk);
719 cf_sk->conn_req.param.size = ol;
720 release_sock(&cf_sk->sk);
734 * caif_connect() - Connect a CAIF Socket
735 * Copied and modified af_irda.c:irda_connect().
737 * Note : by consulting "errno", the user space caller may learn the cause
738 * of the failure. Most of them are visible in the function, others may come
739 * from subroutines called and are listed here :
740 * o -EAFNOSUPPORT: bad socket family or type.
741 * o -ESOCKTNOSUPPORT: bad socket type or protocol
742 * o -EINVAL: bad socket address, or CAIF link type
743 * o -ECONNREFUSED: remote end refused the connection.
744 * o -EINPROGRESS: connect request sent but timed out (or non-blocking)
745 * o -EISCONN: already connected.
746 * o -ETIMEDOUT: Connection timed out (send timeout)
747 * o -ENODEV: No link layer to send request
748 * o -ECONNRESET: Received Shutdown indication or lost link layer
749 * o -ENOMEM: Out of memory
752 * o sk_state: holds the CAIF_* protocol state, it's updated by
754 * o sock->state: holds the SS_* socket state and is updated by connect and
757 static int caif_connect(struct socket *sock, struct sockaddr *uaddr,
758 int addr_len, int flags)
760 struct sock *sk = sock->sk;
761 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
764 int ifindex, headroom, tailroom;
766 struct net_device *dev;
771 if (uaddr->sa_family != AF_CAIF)
774 switch (sock->state) {
776 /* Normal case, a fresh connect */
777 caif_assert(sk->sk_state == CAIF_DISCONNECTED);
780 switch (sk->sk_state) {
782 sock->state = SS_CONNECTED;
785 case CAIF_DISCONNECTED:
786 /* Reconnect allowed */
788 case CAIF_CONNECTING:
790 if (flags & O_NONBLOCK)
796 caif_assert(sk->sk_state == CAIF_CONNECTED ||
797 sk->sk_state == CAIF_DISCONNECTED);
798 if (sk->sk_shutdown & SHUTDOWN_MASK) {
799 /* Allow re-connect after SHUTDOWN_IND */
800 caif_disconnect_client(&cf_sk->layer);
803 /* No reconnect on a seqpacket socket */
806 case SS_DISCONNECTING:
808 caif_assert(1); /*Should never happen */
811 sk->sk_state = CAIF_DISCONNECTED;
812 sock->state = SS_UNCONNECTED;
813 sk_stream_kill_queues(&cf_sk->sk);
816 if (addr_len != sizeof(struct sockaddr_caif))
819 memcpy(&cf_sk->conn_req.sockaddr, uaddr,
820 sizeof(struct sockaddr_caif));
822 /* Move to connecting socket, start sending Connect Requests */
823 sock->state = SS_CONNECTING;
824 sk->sk_state = CAIF_CONNECTING;
826 /* Check priority value coming from socket */
827 /* if priority value is out of range it will be ajusted */
828 if (cf_sk->sk.sk_priority > CAIF_PRIO_MAX)
829 cf_sk->conn_req.priority = CAIF_PRIO_MAX;
830 else if (cf_sk->sk.sk_priority < CAIF_PRIO_MIN)
831 cf_sk->conn_req.priority = CAIF_PRIO_MIN;
833 cf_sk->conn_req.priority = cf_sk->sk.sk_priority;
835 /*ifindex = id of the interface.*/
836 cf_sk->conn_req.ifindex = cf_sk->sk.sk_bound_dev_if;
838 dbfs_atomic_inc(&cnt.num_connect_req);
839 cf_sk->layer.receive = caif_sktrecv_cb;
840 err = caif_connect_client(&cf_sk->conn_req,
841 &cf_sk->layer, &ifindex, &headroom, &tailroom);
843 cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
844 cf_sk->sk.sk_state = CAIF_DISCONNECTED;
850 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
855 cf_sk->headroom = LL_RESERVED_SPACE_EXTRA(dev, headroom);
859 cf_sk->tailroom = tailroom;
860 cf_sk->maxframe = mtu - (headroom + tailroom);
861 if (cf_sk->maxframe < 1) {
862 pr_warn("CAIF Interface MTU too small (%d)\n", dev->mtu);
870 if (sk->sk_state != CAIF_CONNECTED && (flags & O_NONBLOCK))
873 timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
877 timeo = wait_event_interruptible_timeout(*sk_sleep(sk),
878 sk->sk_state != CAIF_CONNECTING,
882 goto out; /* -ERESTARTSYS */
885 if (timeo == 0 && sk->sk_state != CAIF_CONNECTED)
887 if (sk->sk_state != CAIF_CONNECTED) {
888 sock->state = SS_UNCONNECTED;
889 err = sock_error(sk);
894 sock->state = SS_CONNECTED;
902 * caif_release() - Disconnect a CAIF Socket
903 * Copied and modified af_irda.c:irda_release().
905 static int caif_release(struct socket *sock)
907 struct sock *sk = sock->sk;
908 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
914 set_tx_flow_off(cf_sk);
917 * Ensure that packets are not queued after this point in time.
918 * caif_queue_rcv_skb checks SOCK_DEAD holding the queue lock,
919 * this ensures no packets when sock is dead.
921 spin_lock(&sk->sk_receive_queue.lock);
922 sock_set_flag(sk, SOCK_DEAD);
923 spin_unlock(&sk->sk_receive_queue.lock);
926 dbfs_atomic_inc(&cnt.num_disconnect);
928 if (cf_sk->debugfs_socket_dir != NULL)
929 debugfs_remove_recursive(cf_sk->debugfs_socket_dir);
931 lock_sock(&(cf_sk->sk));
932 sk->sk_state = CAIF_DISCONNECTED;
933 sk->sk_shutdown = SHUTDOWN_MASK;
935 if (cf_sk->sk.sk_socket->state == SS_CONNECTED ||
936 cf_sk->sk.sk_socket->state == SS_CONNECTING)
937 res = caif_disconnect_client(&cf_sk->layer);
939 cf_sk->sk.sk_socket->state = SS_DISCONNECTING;
940 wake_up_interruptible_poll(sk_sleep(sk), POLLERR|POLLHUP);
943 cf_sk->layer.dn = NULL;
944 sk_stream_kill_queues(&cf_sk->sk);
950 /* Copied from af_unix.c:unix_poll(), added CAIF tx_flow handling */
951 static unsigned int caif_poll(struct file *file,
952 struct socket *sock, poll_table *wait)
954 struct sock *sk = sock->sk;
956 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
958 sock_poll_wait(file, sk_sleep(sk), wait);
961 /* exceptional events? */
964 if (sk->sk_shutdown == SHUTDOWN_MASK)
966 if (sk->sk_shutdown & RCV_SHUTDOWN)
970 if (!skb_queue_empty(&sk->sk_receive_queue) ||
971 (sk->sk_shutdown & RCV_SHUTDOWN))
972 mask |= POLLIN | POLLRDNORM;
975 * we set writable also when the other side has shut down the
976 * connection. This prevents stuck sockets.
978 if (sock_writeable(sk) && tx_flow_is_on(cf_sk))
979 mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
984 static const struct proto_ops caif_seqpacket_ops = {
986 .owner = THIS_MODULE,
987 .release = caif_release,
988 .bind = sock_no_bind,
989 .connect = caif_connect,
990 .socketpair = sock_no_socketpair,
991 .accept = sock_no_accept,
992 .getname = sock_no_getname,
994 .ioctl = sock_no_ioctl,
995 .listen = sock_no_listen,
996 .shutdown = sock_no_shutdown,
997 .setsockopt = setsockopt,
998 .getsockopt = sock_no_getsockopt,
999 .sendmsg = caif_seqpkt_sendmsg,
1000 .recvmsg = caif_seqpkt_recvmsg,
1001 .mmap = sock_no_mmap,
1002 .sendpage = sock_no_sendpage,
1005 static const struct proto_ops caif_stream_ops = {
1007 .owner = THIS_MODULE,
1008 .release = caif_release,
1009 .bind = sock_no_bind,
1010 .connect = caif_connect,
1011 .socketpair = sock_no_socketpair,
1012 .accept = sock_no_accept,
1013 .getname = sock_no_getname,
1015 .ioctl = sock_no_ioctl,
1016 .listen = sock_no_listen,
1017 .shutdown = sock_no_shutdown,
1018 .setsockopt = setsockopt,
1019 .getsockopt = sock_no_getsockopt,
1020 .sendmsg = caif_stream_sendmsg,
1021 .recvmsg = caif_stream_recvmsg,
1022 .mmap = sock_no_mmap,
1023 .sendpage = sock_no_sendpage,
1026 /* This function is called when a socket is finally destroyed. */
1027 static void caif_sock_destructor(struct sock *sk)
1029 struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
1030 caif_assert(!atomic_read(&sk->sk_wmem_alloc));
1031 caif_assert(sk_unhashed(sk));
1032 caif_assert(!sk->sk_socket);
1033 if (!sock_flag(sk, SOCK_DEAD)) {
1034 pr_info("Attempt to release alive CAIF socket: %p\n", sk);
1037 sk_stream_kill_queues(&cf_sk->sk);
1038 dbfs_atomic_dec(&cnt.caif_nr_socks);
1041 static int caif_create(struct net *net, struct socket *sock, int protocol,
1044 struct sock *sk = NULL;
1045 struct caifsock *cf_sk = NULL;
1046 static struct proto prot = {.name = "PF_CAIF",
1047 .owner = THIS_MODULE,
1048 .obj_size = sizeof(struct caifsock),
1051 if (!capable(CAP_SYS_ADMIN) && !capable(CAP_NET_ADMIN))
1054 * The sock->type specifies the socket type to use.
1055 * The CAIF socket is a packet stream in the sense
1056 * that it is packet based. CAIF trusts the reliability
1057 * of the link, no resending is implemented.
1059 if (sock->type == SOCK_SEQPACKET)
1060 sock->ops = &caif_seqpacket_ops;
1061 else if (sock->type == SOCK_STREAM)
1062 sock->ops = &caif_stream_ops;
1064 return -ESOCKTNOSUPPORT;
1066 if (protocol < 0 || protocol >= CAIFPROTO_MAX)
1067 return -EPROTONOSUPPORT;
1069 * Set the socket state to unconnected. The socket state
1070 * is really not used at all in the net/core or socket.c but the
1071 * initialization makes sure that sock->state is not uninitialized.
1073 sk = sk_alloc(net, PF_CAIF, GFP_KERNEL, &prot);
1077 cf_sk = container_of(sk, struct caifsock, sk);
1079 /* Store the protocol */
1080 sk->sk_protocol = (unsigned char) protocol;
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->sk.sk_priority= CAIF_PRIO_NORMAL;
1102 cf_sk->conn_req.link_selector = CAIF_LINK_LOW_LATENCY;
1103 cf_sk->conn_req.protocol = protocol;
1104 /* Increase the number of sockets created. */
1105 dbfs_atomic_inc(&cnt.caif_nr_socks);
1106 #ifdef CONFIG_DEBUG_FS
1107 if (!IS_ERR(debugfsdir)) {
1108 /* Fill in some information concerning the misc socket. */
1109 snprintf(cf_sk->name, sizeof(cf_sk->name), "cfsk%d",
1110 atomic_read(&cnt.caif_nr_socks));
1112 cf_sk->debugfs_socket_dir =
1113 debugfs_create_dir(cf_sk->name, debugfsdir);
1114 debugfs_create_u32("sk_state", S_IRUSR | S_IWUSR,
1115 cf_sk->debugfs_socket_dir,
1116 (u32 *) &cf_sk->sk.sk_state);
1117 debugfs_create_u32("flow_state", S_IRUSR | S_IWUSR,
1118 cf_sk->debugfs_socket_dir, &cf_sk->flow_state);
1119 debugfs_create_u32("sk_rmem_alloc", S_IRUSR | S_IWUSR,
1120 cf_sk->debugfs_socket_dir,
1121 (u32 *) &cf_sk->sk.sk_rmem_alloc);
1122 debugfs_create_u32("sk_wmem_alloc", S_IRUSR | S_IWUSR,
1123 cf_sk->debugfs_socket_dir,
1124 (u32 *) &cf_sk->sk.sk_wmem_alloc);
1125 debugfs_create_u32("identity", S_IRUSR | S_IWUSR,
1126 cf_sk->debugfs_socket_dir,
1127 (u32 *) &cf_sk->layer.id);
1130 release_sock(&cf_sk->sk);
1135 static struct net_proto_family caif_family_ops = {
1137 .create = caif_create,
1138 .owner = THIS_MODULE,
1141 static int af_caif_init(void)
1143 int err = sock_register(&caif_family_ops);
1149 static int __init caif_sktinit_module(void)
1151 #ifdef CONFIG_DEBUG_FS
1152 debugfsdir = debugfs_create_dir("caif_sk", NULL);
1153 if (!IS_ERR(debugfsdir)) {
1154 debugfs_create_u32("num_sockets", S_IRUSR | S_IWUSR,
1156 (u32 *) &cnt.caif_nr_socks);
1157 debugfs_create_u32("num_connect_req", S_IRUSR | S_IWUSR,
1159 (u32 *) &cnt.num_connect_req);
1160 debugfs_create_u32("num_connect_resp", S_IRUSR | S_IWUSR,
1162 (u32 *) &cnt.num_connect_resp);
1163 debugfs_create_u32("num_connect_fail_resp", S_IRUSR | S_IWUSR,
1165 (u32 *) &cnt.num_connect_fail_resp);
1166 debugfs_create_u32("num_disconnect", S_IRUSR | S_IWUSR,
1168 (u32 *) &cnt.num_disconnect);
1169 debugfs_create_u32("num_remote_shutdown_ind",
1170 S_IRUSR | S_IWUSR, debugfsdir,
1171 (u32 *) &cnt.num_remote_shutdown_ind);
1172 debugfs_create_u32("num_tx_flow_off_ind", S_IRUSR | S_IWUSR,
1174 (u32 *) &cnt.num_tx_flow_off_ind);
1175 debugfs_create_u32("num_tx_flow_on_ind", S_IRUSR | S_IWUSR,
1177 (u32 *) &cnt.num_tx_flow_on_ind);
1178 debugfs_create_u32("num_rx_flow_off", S_IRUSR | S_IWUSR,
1180 (u32 *) &cnt.num_rx_flow_off);
1181 debugfs_create_u32("num_rx_flow_on", S_IRUSR | S_IWUSR,
1183 (u32 *) &cnt.num_rx_flow_on);
1186 return af_caif_init();
1189 static void __exit caif_sktexit_module(void)
1191 sock_unregister(PF_CAIF);
1192 if (debugfsdir != NULL)
1193 debugfs_remove_recursive(debugfsdir);
1195 module_init(caif_sktinit_module);
1196 module_exit(caif_sktexit_module);