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-rw-r--r--net/caif/caif_socket.c1252
1 files changed, 1252 insertions, 0 deletions
diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c
new file mode 100644
index 0000000..c3a70c5
--- /dev/null
+++ b/net/caif/caif_socket.c
@@ -0,0 +1,1252 @@
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Author: Sjur Brendeland sjur.brandeland@stericsson.com
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+#include <linux/poll.h>
+#include <linux/tcp.h>
+#include <linux/uaccess.h>
+#include <linux/mutex.h>
+#include <linux/debugfs.h>
+#include <linux/caif/caif_socket.h>
+#include <asm/atomic.h>
+#include <net/sock.h>
+#include <net/tcp_states.h>
+#include <net/caif/caif_layer.h>
+#include <net/caif/caif_dev.h>
+#include <net/caif/cfpkt.h>
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(AF_CAIF);
+
+#define CAIF_DEF_SNDBUF (CAIF_MAX_PAYLOAD_SIZE*10)
+#define CAIF_DEF_RCVBUF (CAIF_MAX_PAYLOAD_SIZE*100)
+
+/*
+ * CAIF state is re-using the TCP socket states.
+ * caif_states stored in sk_state reflect the state as reported by
+ * the CAIF stack, while sk_socket->state is the state of the socket.
+ */
+enum caif_states {
+ CAIF_CONNECTED = TCP_ESTABLISHED,
+ CAIF_CONNECTING = TCP_SYN_SENT,
+ CAIF_DISCONNECTED = TCP_CLOSE
+};
+
+#define TX_FLOW_ON_BIT 1
+#define RX_FLOW_ON_BIT 2
+
+static struct dentry *debugfsdir;
+
+#ifdef CONFIG_DEBUG_FS
+struct debug_fs_counter {
+ atomic_t caif_nr_socks;
+ atomic_t num_connect_req;
+ atomic_t num_connect_resp;
+ atomic_t num_connect_fail_resp;
+ atomic_t num_disconnect;
+ atomic_t num_remote_shutdown_ind;
+ atomic_t num_tx_flow_off_ind;
+ atomic_t num_tx_flow_on_ind;
+ atomic_t num_rx_flow_off;
+ atomic_t num_rx_flow_on;
+};
+struct debug_fs_counter cnt;
+#define dbfs_atomic_inc(v) atomic_inc(v)
+#define dbfs_atomic_dec(v) atomic_dec(v)
+#else
+#define dbfs_atomic_inc(v)
+#define dbfs_atomic_dec(v)
+#endif
+
+struct caifsock {
+ struct sock sk; /* must be first member */
+ struct cflayer layer;
+ char name[CAIF_LAYER_NAME_SZ]; /* Used for debugging */
+ u32 flow_state;
+ struct caif_connect_request conn_req;
+ struct mutex readlock;
+ struct dentry *debugfs_socket_dir;
+};
+
+static int rx_flow_is_on(struct caifsock *cf_sk)
+{
+ return test_bit(RX_FLOW_ON_BIT,
+ (void *) &cf_sk->flow_state);
+}
+
+static int tx_flow_is_on(struct caifsock *cf_sk)
+{
+ return test_bit(TX_FLOW_ON_BIT,
+ (void *) &cf_sk->flow_state);
+}
+
+static void set_rx_flow_off(struct caifsock *cf_sk)
+{
+ clear_bit(RX_FLOW_ON_BIT,
+ (void *) &cf_sk->flow_state);
+}
+
+static void set_rx_flow_on(struct caifsock *cf_sk)
+{
+ set_bit(RX_FLOW_ON_BIT,
+ (void *) &cf_sk->flow_state);
+}
+
+static void set_tx_flow_off(struct caifsock *cf_sk)
+{
+ clear_bit(TX_FLOW_ON_BIT,
+ (void *) &cf_sk->flow_state);
+}
+
+static void set_tx_flow_on(struct caifsock *cf_sk)
+{
+ set_bit(TX_FLOW_ON_BIT,
+ (void *) &cf_sk->flow_state);
+}
+
+static void caif_read_lock(struct sock *sk)
+{
+ struct caifsock *cf_sk;
+ cf_sk = container_of(sk, struct caifsock, sk);
+ mutex_lock(&cf_sk->readlock);
+}
+
+static void caif_read_unlock(struct sock *sk)
+{
+ struct caifsock *cf_sk;
+ cf_sk = container_of(sk, struct caifsock, sk);
+ mutex_unlock(&cf_sk->readlock);
+}
+
+int sk_rcvbuf_lowwater(struct caifsock *cf_sk)
+{
+ /* A quarter of full buffer is used a low water mark */
+ return cf_sk->sk.sk_rcvbuf / 4;
+}
+
+void caif_flow_ctrl(struct sock *sk, int mode)
+{
+ struct caifsock *cf_sk;
+ cf_sk = container_of(sk, struct caifsock, sk);
+ if (cf_sk->layer.dn)
+ cf_sk->layer.dn->modemcmd(cf_sk->layer.dn, mode);
+}
+
+/*
+ * Copied from sock.c:sock_queue_rcv_skb(), but changed so packets are
+ * not dropped, but CAIF is sending flow off instead.
+ */
+int caif_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
+{
+ int err;
+ int skb_len;
+ unsigned long flags;
+ struct sk_buff_head *list = &sk->sk_receive_queue;
+ struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+
+ if (atomic_read(&sk->sk_rmem_alloc) + skb->truesize >=
+ (unsigned)sk->sk_rcvbuf && rx_flow_is_on(cf_sk)) {
+ trace_printk("CAIF: %s():"
+ " sending flow OFF (queue len = %d %d)\n",
+ __func__,
+ atomic_read(&cf_sk->sk.sk_rmem_alloc),
+ sk_rcvbuf_lowwater(cf_sk));
+ set_rx_flow_off(cf_sk);
+ if (cf_sk->layer.dn)
+ cf_sk->layer.dn->modemcmd(cf_sk->layer.dn,
+ CAIF_MODEMCMD_FLOW_OFF_REQ);
+ }
+
+ err = sk_filter(sk, skb);
+ if (err)
+ return err;
+ if (!sk_rmem_schedule(sk, skb->truesize) && rx_flow_is_on(cf_sk)) {
+ set_rx_flow_off(cf_sk);
+ trace_printk("CAIF: %s():"
+ " sending flow OFF due to rmem_schedule\n",
+ __func__);
+ if (cf_sk->layer.dn)
+ cf_sk->layer.dn->modemcmd(cf_sk->layer.dn,
+ CAIF_MODEMCMD_FLOW_OFF_REQ);
+ }
+ skb->dev = NULL;
+ skb_set_owner_r(skb, sk);
+ /* Cache the SKB length before we tack it onto the receive
+ * queue. Once it is added it no longer belongs to us and
+ * may be freed by other threads of control pulling packets
+ * from the queue.
+ */
+ skb_len = skb->len;
+ spin_lock_irqsave(&list->lock, flags);
+ if (!sock_flag(sk, SOCK_DEAD))
+ __skb_queue_tail(list, skb);
+ spin_unlock_irqrestore(&list->lock, flags);
+
+ if (!sock_flag(sk, SOCK_DEAD))
+ sk->sk_data_ready(sk, skb_len);
+ else
+ kfree_skb(skb);
+ return 0;
+}
+
+/* Packet Receive Callback function called from CAIF Stack */
+static int caif_sktrecv_cb(struct cflayer *layr, struct cfpkt *pkt)
+{
+ struct caifsock *cf_sk;
+ struct sk_buff *skb;
+
+ cf_sk = container_of(layr, struct caifsock, layer);
+ skb = cfpkt_tonative(pkt);
+
+ if (unlikely(cf_sk->sk.sk_state != CAIF_CONNECTED)) {
+ cfpkt_destroy(pkt);
+ return 0;
+ }
+ caif_queue_rcv_skb(&cf_sk->sk, skb);
+ return 0;
+}
+
+/* Packet Control Callback function called from CAIF */
+static void caif_ctrl_cb(struct cflayer *layr,
+ enum caif_ctrlcmd flow,
+ int phyid)
+{
+ struct caifsock *cf_sk = container_of(layr, struct caifsock, layer);
+ switch (flow) {
+ case CAIF_CTRLCMD_FLOW_ON_IND:
+ /* OK from modem to start sending again */
+ dbfs_atomic_inc(&cnt.num_tx_flow_on_ind);
+ set_tx_flow_on(cf_sk);
+ cf_sk->sk.sk_state_change(&cf_sk->sk);
+ break;
+
+ case CAIF_CTRLCMD_FLOW_OFF_IND:
+ /* Modem asks us to shut up */
+ dbfs_atomic_inc(&cnt.num_tx_flow_off_ind);
+ set_tx_flow_off(cf_sk);
+ cf_sk->sk.sk_state_change(&cf_sk->sk);
+ break;
+
+ case CAIF_CTRLCMD_INIT_RSP:
+ /* We're now connected */
+ dbfs_atomic_inc(&cnt.num_connect_resp);
+ cf_sk->sk.sk_state = CAIF_CONNECTED;
+ set_tx_flow_on(cf_sk);
+ cf_sk->sk.sk_state_change(&cf_sk->sk);
+ break;
+
+ case CAIF_CTRLCMD_DEINIT_RSP:
+ /* We're now disconnected */
+ cf_sk->sk.sk_state = CAIF_DISCONNECTED;
+ cf_sk->sk.sk_state_change(&cf_sk->sk);
+ cfcnfg_release_adap_layer(&cf_sk->layer);
+ break;
+
+ case CAIF_CTRLCMD_INIT_FAIL_RSP:
+ /* Connect request failed */
+ dbfs_atomic_inc(&cnt.num_connect_fail_resp);
+ cf_sk->sk.sk_err = ECONNREFUSED;
+ cf_sk->sk.sk_state = CAIF_DISCONNECTED;
+ cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
+ /*
+ * Socket "standards" seems to require POLLOUT to
+ * be set at connect failure.
+ */
+ set_tx_flow_on(cf_sk);
+ cf_sk->sk.sk_state_change(&cf_sk->sk);
+ break;
+
+ case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND:
+ /* Modem has closed this connection, or device is down. */
+ dbfs_atomic_inc(&cnt.num_remote_shutdown_ind);
+ cf_sk->sk.sk_shutdown = SHUTDOWN_MASK;
+ cf_sk->sk.sk_err = ECONNRESET;
+ set_rx_flow_on(cf_sk);
+ cf_sk->sk.sk_error_report(&cf_sk->sk);
+ break;
+
+ default:
+ pr_debug("CAIF: %s(): Unexpected flow command %d\n",
+ __func__, flow);
+ }
+}
+
+static void caif_check_flow_release(struct sock *sk)
+{
+ struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+
+ if (cf_sk->layer.dn == NULL || cf_sk->layer.dn->modemcmd == NULL)
+ return;
+ if (rx_flow_is_on(cf_sk))
+ return;
+
+ if (atomic_read(&sk->sk_rmem_alloc) <= sk_rcvbuf_lowwater(cf_sk)) {
+ dbfs_atomic_inc(&cnt.num_rx_flow_on);
+ set_rx_flow_on(cf_sk);
+ cf_sk->layer.dn->modemcmd(cf_sk->layer.dn,
+ CAIF_MODEMCMD_FLOW_ON_REQ);
+ }
+}
+/*
+ * Copied from sock.c:sock_queue_rcv_skb(), and added check that user buffer
+ * has sufficient size.
+ */
+
+static int caif_seqpkt_recvmsg(struct kiocb *iocb, struct socket *sock,
+ struct msghdr *m, size_t buf_len, int flags)
+
+{
+ struct sock *sk = sock->sk;
+ struct sk_buff *skb;
+ int ret = 0;
+ int len;
+
+ if (unlikely(!buf_len))
+ return -EINVAL;
+
+ skb = skb_recv_datagram(sk, flags, 0 , &ret);
+ if (!skb)
+ goto read_error;
+
+ len = skb->len;
+
+ if (skb && skb->len > buf_len && !(flags & MSG_PEEK)) {
+ len = buf_len;
+ /*
+ * Push skb back on receive queue if buffer too small.
+ * This has a built-in race where multi-threaded receive
+ * may get packet in wrong order, but multiple read does
+ * not really guarantee ordered delivery anyway.
+ * Let's optimize for speed without taking locks.
+ */
+
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ ret = -EMSGSIZE;
+ goto read_error;
+ }
+
+ ret = skb_copy_datagram_iovec(skb, 0, m->msg_iov, len);
+ if (ret)
+ goto read_error;
+
+ skb_free_datagram(sk, skb);
+
+ caif_check_flow_release(sk);
+
+ return len;
+
+read_error:
+ return ret;
+}
+
+
+/* Copied from unix_stream_wait_data, identical except for lock call. */
+static long caif_stream_data_wait(struct sock *sk, long timeo)
+{
+ DEFINE_WAIT(wait);
+ lock_sock(sk);
+
+ for (;;) {
+ prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+
+ if (!skb_queue_empty(&sk->sk_receive_queue) ||
+ sk->sk_err ||
+ sk->sk_state != CAIF_CONNECTED ||
+ sock_flag(sk, SOCK_DEAD) ||
+ (sk->sk_shutdown & RCV_SHUTDOWN) ||
+ signal_pending(current) ||
+ !timeo)
+ break;
+
+ set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+ release_sock(sk);
+ timeo = schedule_timeout(timeo);
+ lock_sock(sk);
+ clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+ }
+
+ finish_wait(sk_sleep(sk), &wait);
+ release_sock(sk);
+ return timeo;
+}
+
+
+/*
+ * Copied from unix_stream_recvmsg, but removed credit checks,
+ * changed locking calls, changed address handling.
+ */
+static int caif_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
+ struct msghdr *msg, size_t size,
+ int flags)
+{
+ struct sock *sk = sock->sk;
+ int copied = 0;
+ int target;
+ int err = 0;
+ long timeo;
+
+ err = -EOPNOTSUPP;
+ if (flags&MSG_OOB)
+ goto out;
+
+ msg->msg_namelen = 0;
+
+ /*
+ * Lock the socket to prevent queue disordering
+ * while sleeps in memcpy_tomsg
+ */
+ err = -EAGAIN;
+ if (sk->sk_state == CAIF_CONNECTING)
+ goto out;
+
+ caif_read_lock(sk);
+ target = sock_rcvlowat(sk, flags&MSG_WAITALL, size);
+ timeo = sock_rcvtimeo(sk, flags&MSG_DONTWAIT);
+
+ do {
+ int chunk;
+ struct sk_buff *skb;
+
+ lock_sock(sk);
+ skb = skb_dequeue(&sk->sk_receive_queue);
+ caif_check_flow_release(sk);
+
+ if (skb == NULL) {
+ if (copied >= target)
+ goto unlock;
+ /*
+ * POSIX 1003.1g mandates this order.
+ */
+ err = sock_error(sk);
+ if (err)
+ goto unlock;
+ err = -ECONNRESET;
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ goto unlock;
+
+ err = -EPIPE;
+ if (sk->sk_state != CAIF_CONNECTED)
+ goto unlock;
+ if (sock_flag(sk, SOCK_DEAD))
+ goto unlock;
+
+ release_sock(sk);
+
+ err = -EAGAIN;
+ if (!timeo)
+ break;
+
+ caif_read_unlock(sk);
+
+ timeo = caif_stream_data_wait(sk, timeo);
+
+ if (signal_pending(current)) {
+ err = sock_intr_errno(timeo);
+ goto out;
+ }
+ caif_read_lock(sk);
+ continue;
+unlock:
+ release_sock(sk);
+ break;
+ }
+ release_sock(sk);
+ chunk = min_t(unsigned int, skb->len, size);
+ if (memcpy_toiovec(msg->msg_iov, skb->data, chunk)) {
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ if (copied == 0)
+ copied = -EFAULT;
+ break;
+ }
+ copied += chunk;
+ size -= chunk;
+
+ /* Mark read part of skb as used */
+ if (!(flags & MSG_PEEK)) {
+ skb_pull(skb, chunk);
+
+ /* put the skb back if we didn't use it up. */
+ if (skb->len) {
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ break;
+ }
+ kfree_skb(skb);
+
+ } else {
+ /*
+ * It is questionable, see note in unix_dgram_recvmsg.
+ */
+ /* put message back and return */
+ skb_queue_head(&sk->sk_receive_queue, skb);
+ break;
+ }
+ } while (size);
+ caif_read_unlock(sk);
+
+out:
+ return copied ? : err;
+}
+
+/*
+ * Copied from sock.c:sock_wait_for_wmem, but change to wait for
+ * CAIF flow-on and sock_writable.
+ */
+static long caif_wait_for_flow_on(struct caifsock *cf_sk,
+ int wait_writeable, long timeo, int *err)
+{
+ struct sock *sk = &cf_sk->sk;
+ DEFINE_WAIT(wait);
+ for (;;) {
+ *err = 0;
+ if (tx_flow_is_on(cf_sk) &&
+ (!wait_writeable || sock_writeable(&cf_sk->sk)))
+ break;
+ *err = -ETIMEDOUT;
+ if (!timeo)
+ break;
+ *err = -ERESTARTSYS;
+ if (signal_pending(current))
+ break;
+ prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+ *err = -ECONNRESET;
+ if (sk->sk_shutdown & SHUTDOWN_MASK)
+ break;
+ *err = -sk->sk_err;
+ if (sk->sk_err)
+ break;
+ *err = -EPIPE;
+ if (cf_sk->sk.sk_state != CAIF_CONNECTED)
+ break;
+ timeo = schedule_timeout(timeo);
+ }
+ finish_wait(sk_sleep(sk), &wait);
+ return timeo;
+}
+
+/*
+ * Transmit a SKB. The device may temporarily request re-transmission
+ * by returning EAGAIN.
+ */
+static int transmit_skb(struct sk_buff *skb, struct caifsock *cf_sk,
+ int noblock, long timeo)
+{
+ struct cfpkt *pkt;
+ int ret, loopcnt = 0;
+
+ pkt = cfpkt_fromnative(CAIF_DIR_OUT, skb);
+ memset(cfpkt_info(pkt), 0, sizeof(struct caif_payload_info));
+ do {
+
+ ret = -ETIMEDOUT;
+
+ /* Slight paranoia, probably not needed. */
+ if (unlikely(loopcnt++ > 1000)) {
+ pr_warning("CAIF: %s(): transmit retries failed,"
+ " error = %d\n", __func__, ret);
+ break;
+ }
+
+ if (cf_sk->layer.dn != NULL)
+ ret = cf_sk->layer.dn->transmit(cf_sk->layer.dn, pkt);
+ if (likely(ret >= 0))
+ break;
+ /* if transmit return -EAGAIN, then retry */
+ if (noblock && ret == -EAGAIN)
+ break;
+ timeo = caif_wait_for_flow_on(cf_sk, 0, timeo, &ret);
+ if (signal_pending(current)) {
+ ret = sock_intr_errno(timeo);
+ break;
+ }
+ if (ret)
+ break;
+ if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
+ sock_flag(&cf_sk->sk, SOCK_DEAD) ||
+ (cf_sk->sk.sk_shutdown & RCV_SHUTDOWN)) {
+ ret = -EPIPE;
+ cf_sk->sk.sk_err = EPIPE;
+ break;
+ }
+ } while (ret == -EAGAIN);
+ return ret;
+}
+
+/* Copied from af_unix:unix_dgram_sendmsg, and adapted to CAIF */
+static int caif_seqpkt_sendmsg(struct kiocb *kiocb, struct socket *sock,
+ struct msghdr *msg, size_t len)
+{
+ struct sock *sk = sock->sk;
+ struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+ int buffer_size;
+ int ret = 0;
+ struct sk_buff *skb = NULL;
+ int noblock;
+ long timeo;
+ caif_assert(cf_sk);
+ ret = sock_error(sk);
+ if (ret)
+ goto err;
+
+ ret = -EOPNOTSUPP;
+ if (msg->msg_flags&MSG_OOB)
+ goto err;
+
+ ret = -EOPNOTSUPP;
+ if (msg->msg_namelen)
+ goto err;
+
+ ret = -EINVAL;
+ if (unlikely(msg->msg_iov->iov_base == NULL))
+ goto err;
+ noblock = msg->msg_flags & MSG_DONTWAIT;
+
+ buffer_size = len + CAIF_NEEDED_HEADROOM + CAIF_NEEDED_TAILROOM;
+
+ ret = -EMSGSIZE;
+ if (buffer_size > CAIF_MAX_PAYLOAD_SIZE)
+ goto err;
+
+ timeo = sock_sndtimeo(sk, noblock);
+ timeo = caif_wait_for_flow_on(container_of(sk, struct caifsock, sk),
+ 1, timeo, &ret);
+
+ ret = -EPIPE;
+ if (cf_sk->sk.sk_state != CAIF_CONNECTED ||
+ sock_flag(sk, SOCK_DEAD) ||
+ (sk->sk_shutdown & RCV_SHUTDOWN))
+ goto err;
+
+ ret = -ENOMEM;
+ skb = sock_alloc_send_skb(sk, buffer_size, noblock, &ret);
+ if (!skb)
+ goto err;
+ skb_reserve(skb, CAIF_NEEDED_HEADROOM);
+
+ ret = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
+
+ if (ret)
+ goto err;
+ ret = transmit_skb(skb, cf_sk, noblock, timeo);
+ if (ret < 0)
+ goto err;
+ return len;
+err:
+ kfree_skb(skb);
+ return ret;
+}
+
+/*
+ * Copied from unix_stream_sendmsg and adapted to CAIF:
+ * Changed removed permission handling and added waiting for flow on
+ * and other minor adaptations.
+ */
+static int caif_stream_sendmsg(struct kiocb *kiocb, struct socket *sock,
+ struct msghdr *msg, size_t len)
+{
+ struct sock *sk = sock->sk;
+ struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+ int err, size;
+ struct sk_buff *skb;
+ int sent = 0;
+ long timeo;
+
+ err = -EOPNOTSUPP;
+
+ if (unlikely(msg->msg_flags&MSG_OOB))
+ goto out_err;
+
+ if (unlikely(msg->msg_namelen))
+ goto out_err;
+
+ timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
+ timeo = caif_wait_for_flow_on(cf_sk, 1, timeo, &err);
+
+ if (unlikely(sk->sk_shutdown & SEND_SHUTDOWN))
+ goto pipe_err;
+
+ while (sent < len) {
+
+ size = len-sent;
+
+ if (size > CAIF_MAX_PAYLOAD_SIZE)
+ size = CAIF_MAX_PAYLOAD_SIZE;
+
+ /* If size is more than half of sndbuf, chop up message */
+ if (size > ((sk->sk_sndbuf >> 1) - 64))
+ size = (sk->sk_sndbuf >> 1) - 64;
+
+ if (size > SKB_MAX_ALLOC)
+ size = SKB_MAX_ALLOC;
+
+ skb = sock_alloc_send_skb(sk,
+ size + CAIF_NEEDED_HEADROOM
+ + CAIF_NEEDED_TAILROOM,
+ msg->msg_flags&MSG_DONTWAIT,
+ &err);
+ if (skb == NULL)
+ goto out_err;
+
+ skb_reserve(skb, CAIF_NEEDED_HEADROOM);
+ /*
+ * If you pass two values to the sock_alloc_send_skb
+ * it tries to grab the large buffer with GFP_NOFS
+ * (which can fail easily), and if it fails grab the
+ * fallback size buffer which is under a page and will
+ * succeed. [Alan]
+ */
+ size = min_t(int, size, skb_tailroom(skb));
+
+ err = memcpy_fromiovec(skb_put(skb, size), msg->msg_iov, size);
+ if (err) {
+ kfree_skb(skb);
+ goto out_err;
+ }
+ err = transmit_skb(skb, cf_sk,
+ msg->msg_flags&MSG_DONTWAIT, timeo);
+ if (err < 0) {
+ kfree_skb(skb);
+ goto pipe_err;
+ }
+ sent += size;
+ }
+
+ return sent;
+
+pipe_err:
+ if (sent == 0 && !(msg->msg_flags&MSG_NOSIGNAL))
+ send_sig(SIGPIPE, current, 0);
+ err = -EPIPE;
+out_err:
+ return sent ? : err;
+}
+
+static int setsockopt(struct socket *sock,
+ int lvl, int opt, char __user *ov, unsigned int ol)
+{
+ struct sock *sk = sock->sk;
+ struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+ int prio, linksel;
+ struct ifreq ifreq;
+
+ if (cf_sk->sk.sk_socket->state != SS_UNCONNECTED)
+ return -ENOPROTOOPT;
+
+ switch (opt) {
+ case CAIFSO_LINK_SELECT:
+ if (ol < sizeof(int))
+ return -EINVAL;
+ if (lvl != SOL_CAIF)
+ goto bad_sol;
+ if (copy_from_user(&linksel, ov, sizeof(int)))
+ return -EINVAL;
+ lock_sock(&(cf_sk->sk));
+ cf_sk->conn_req.link_selector = linksel;
+ release_sock(&cf_sk->sk);
+ return 0;
+
+ case SO_PRIORITY:
+ if (lvl != SOL_SOCKET)
+ goto bad_sol;
+ if (ol < sizeof(int))
+ return -EINVAL;
+ if (copy_from_user(&prio, ov, sizeof(int)))
+ return -EINVAL;
+ lock_sock(&(cf_sk->sk));
+ cf_sk->conn_req.priority = prio;
+ release_sock(&cf_sk->sk);
+ return 0;
+
+ case SO_BINDTODEVICE:
+ if (lvl != SOL_SOCKET)
+ goto bad_sol;
+ if (ol < sizeof(struct ifreq))
+ return -EINVAL;
+ if (copy_from_user(&ifreq, ov, sizeof(ifreq)))
+ return -EFAULT;
+ lock_sock(&(cf_sk->sk));
+ strncpy(cf_sk->conn_req.link_name, ifreq.ifr_name,
+ sizeof(cf_sk->conn_req.link_name));
+ cf_sk->conn_req.link_name
+ [sizeof(cf_sk->conn_req.link_name)-1] = 0;
+ release_sock(&cf_sk->sk);
+ return 0;
+
+ case CAIFSO_REQ_PARAM:
+ if (lvl != SOL_CAIF)
+ goto bad_sol;
+ if (cf_sk->sk.sk_protocol != CAIFPROTO_UTIL)
+ return -ENOPROTOOPT;
+ lock_sock(&(cf_sk->sk));
+ cf_sk->conn_req.param.size = ol;
+ if (ol > sizeof(cf_sk->conn_req.param.data) ||
+ copy_from_user(&cf_sk->conn_req.param.data, ov, ol)) {
+ release_sock(&cf_sk->sk);
+ return -EINVAL;
+ }
+ release_sock(&cf_sk->sk);
+ return 0;
+
+ default:
+ return -ENOPROTOOPT;
+ }
+
+ return 0;
+bad_sol:
+ return -ENOPROTOOPT;
+
+}
+
+/*
+ * caif_connect() - Connect a CAIF Socket
+ * Copied and modified af_irda.c:irda_connect().
+ *
+ * Note : by consulting "errno", the user space caller may learn the cause
+ * of the failure. Most of them are visible in the function, others may come
+ * from subroutines called and are listed here :
+ * o -EAFNOSUPPORT: bad socket family or type.
+ * o -ESOCKTNOSUPPORT: bad socket type or protocol
+ * o -EINVAL: bad socket address, or CAIF link type
+ * o -ECONNREFUSED: remote end refused the connection.
+ * o -EINPROGRESS: connect request sent but timed out (or non-blocking)
+ * o -EISCONN: already connected.
+ * o -ETIMEDOUT: Connection timed out (send timeout)
+ * o -ENODEV: No link layer to send request
+ * o -ECONNRESET: Received Shutdown indication or lost link layer
+ * o -ENOMEM: Out of memory
+ *
+ * State Strategy:
+ * o sk_state: holds the CAIF_* protocol state, it's updated by
+ * caif_ctrl_cb.
+ * o sock->state: holds the SS_* socket state and is updated by connect and
+ * disconnect.
+ */
+static int caif_connect(struct socket *sock, struct sockaddr *uaddr,
+ int addr_len, int flags)
+{
+ struct sock *sk = sock->sk;
+ struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+ long timeo;
+ int err;
+ lock_sock(sk);
+
+ err = -EAFNOSUPPORT;
+ if (uaddr->sa_family != AF_CAIF)
+ goto out;
+
+ err = -ESOCKTNOSUPPORT;
+ if (unlikely(!(sk->sk_type == SOCK_STREAM &&
+ cf_sk->sk.sk_protocol == CAIFPROTO_AT) &&
+ sk->sk_type != SOCK_SEQPACKET))
+ goto out;
+ switch (sock->state) {
+ case SS_UNCONNECTED:
+ /* Normal case, a fresh connect */
+ caif_assert(sk->sk_state == CAIF_DISCONNECTED);
+ break;
+ case SS_CONNECTING:
+ switch (sk->sk_state) {
+ case CAIF_CONNECTED:
+ sock->state = SS_CONNECTED;
+ err = -EISCONN;
+ goto out;
+ case CAIF_DISCONNECTED:
+ /* Reconnect allowed */
+ break;
+ case CAIF_CONNECTING:
+ err = -EALREADY;
+ if (flags & O_NONBLOCK)
+ goto out;
+ goto wait_connect;
+ }
+ break;
+ case SS_CONNECTED:
+ caif_assert(sk->sk_state == CAIF_CONNECTED ||
+ sk->sk_state == CAIF_DISCONNECTED);
+ if (sk->sk_shutdown & SHUTDOWN_MASK) {
+ /* Allow re-connect after SHUTDOWN_IND */
+ caif_disconnect_client(&cf_sk->layer);
+ break;
+ }
+ /* No reconnect on a seqpacket socket */
+ err = -EISCONN;
+ goto out;
+ case SS_DISCONNECTING:
+ case SS_FREE:
+ caif_assert(1); /*Should never happen */
+ break;
+ }
+ sk->sk_state = CAIF_DISCONNECTED;
+ sock->state = SS_UNCONNECTED;
+ sk_stream_kill_queues(&cf_sk->sk);
+
+ err = -EINVAL;
+ if (addr_len != sizeof(struct sockaddr_caif) ||
+ !uaddr)
+ goto out;
+
+ memcpy(&cf_sk->conn_req.sockaddr, uaddr,
+ sizeof(struct sockaddr_caif));
+
+ /* Move to connecting socket, start sending Connect Requests */
+ sock->state = SS_CONNECTING;
+ sk->sk_state = CAIF_CONNECTING;
+
+ dbfs_atomic_inc(&cnt.num_connect_req);
+ cf_sk->layer.receive = caif_sktrecv_cb;
+ err = caif_connect_client(&cf_sk->conn_req,
+ &cf_sk->layer);
+ if (err < 0) {
+ cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
+ cf_sk->sk.sk_state = CAIF_DISCONNECTED;
+ goto out;
+ }
+
+ err = -EINPROGRESS;
+wait_connect:
+
+ if (sk->sk_state != CAIF_CONNECTED && (flags & O_NONBLOCK))
+ goto out;
+
+ timeo = sock_sndtimeo(sk, flags & O_NONBLOCK);
+
+ release_sock(sk);
+ err = wait_event_interruptible_timeout(*sk_sleep(sk),
+ sk->sk_state != CAIF_CONNECTING,
+ timeo);
+ lock_sock(sk);
+ if (err < 0)
+ goto out; /* -ERESTARTSYS */
+ if (err == 0 && sk->sk_state != CAIF_CONNECTED) {
+ err = -ETIMEDOUT;
+ goto out;
+ }
+
+ if (sk->sk_state != CAIF_CONNECTED) {
+ sock->state = SS_UNCONNECTED;
+ err = sock_error(sk);
+ if (!err)
+ err = -ECONNREFUSED;
+ goto out;
+ }
+ sock->state = SS_CONNECTED;
+ err = 0;
+out:
+ release_sock(sk);
+ return err;
+}
+
+
+/*
+ * caif_release() - Disconnect a CAIF Socket
+ * Copied and modified af_irda.c:irda_release().
+ */
+static int caif_release(struct socket *sock)
+{
+ struct sock *sk = sock->sk;
+ struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+ int res = 0;
+
+ if (!sk)
+ return 0;
+
+ set_tx_flow_off(cf_sk);
+
+ /*
+ * Ensure that packets are not queued after this point in time.
+ * caif_queue_rcv_skb checks SOCK_DEAD holding the queue lock,
+ * this ensures no packets when sock is dead.
+ */
+ spin_lock(&sk->sk_receive_queue.lock);
+ sock_set_flag(sk, SOCK_DEAD);
+ spin_unlock(&sk->sk_receive_queue.lock);
+ sock->sk = NULL;
+
+ dbfs_atomic_inc(&cnt.num_disconnect);
+
+ if (cf_sk->debugfs_socket_dir != NULL)
+ debugfs_remove_recursive(cf_sk->debugfs_socket_dir);
+
+ lock_sock(&(cf_sk->sk));
+ sk->sk_state = CAIF_DISCONNECTED;
+ sk->sk_shutdown = SHUTDOWN_MASK;
+
+ if (cf_sk->sk.sk_socket->state == SS_CONNECTED ||
+ cf_sk->sk.sk_socket->state == SS_CONNECTING)
+ res = caif_disconnect_client(&cf_sk->layer);
+
+ cf_sk->sk.sk_socket->state = SS_DISCONNECTING;
+ wake_up_interruptible_poll(sk_sleep(sk), POLLERR|POLLHUP);
+
+ sock_orphan(sk);
+ cf_sk->layer.dn = NULL;
+ sk_stream_kill_queues(&cf_sk->sk);
+ release_sock(sk);
+ sock_put(sk);
+ return res;
+}
+
+/* Copied from af_unix.c:unix_poll(), added CAIF tx_flow handling */
+static unsigned int caif_poll(struct file *file,
+ struct socket *sock, poll_table *wait)
+{
+ struct sock *sk = sock->sk;
+ unsigned int mask;
+ struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+
+ sock_poll_wait(file, sk_sleep(sk), wait);
+ mask = 0;
+
+ /* exceptional events? */
+ if (sk->sk_err)
+ mask |= POLLERR;
+ if (sk->sk_shutdown == SHUTDOWN_MASK)
+ mask |= POLLHUP;
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ mask |= POLLRDHUP;
+
+ /* readable? */
+ if (!skb_queue_empty(&sk->sk_receive_queue) ||
+ (sk->sk_shutdown & RCV_SHUTDOWN))
+ mask |= POLLIN | POLLRDNORM;
+
+ /* Connection-based need to check for termination and startup */
+ if (sk->sk_state == CAIF_DISCONNECTED)
+ mask |= POLLHUP;
+
+ /*
+ * we set writable also when the other side has shut down the
+ * connection. This prevents stuck sockets.
+ */
+ if (sock_writeable(sk) && tx_flow_is_on(cf_sk))
+ mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
+
+ return mask;
+}
+
+static const struct proto_ops caif_seqpacket_ops = {
+ .family = PF_CAIF,
+ .owner = THIS_MODULE,
+ .release = caif_release,
+ .bind = sock_no_bind,
+ .connect = caif_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = sock_no_getname,
+ .poll = caif_poll,
+ .ioctl = sock_no_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = setsockopt,
+ .getsockopt = sock_no_getsockopt,
+ .sendmsg = caif_seqpkt_sendmsg,
+ .recvmsg = caif_seqpkt_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+static const struct proto_ops caif_stream_ops = {
+ .family = PF_CAIF,
+ .owner = THIS_MODULE,
+ .release = caif_release,
+ .bind = sock_no_bind,
+ .connect = caif_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = sock_no_accept,
+ .getname = sock_no_getname,
+ .poll = caif_poll,
+ .ioctl = sock_no_ioctl,
+ .listen = sock_no_listen,
+ .shutdown = sock_no_shutdown,
+ .setsockopt = setsockopt,
+ .getsockopt = sock_no_getsockopt,
+ .sendmsg = caif_stream_sendmsg,
+ .recvmsg = caif_stream_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+};
+
+/* This function is called when a socket is finally destroyed. */
+static void caif_sock_destructor(struct sock *sk)
+{
+ struct caifsock *cf_sk = container_of(sk, struct caifsock, sk);
+ caif_assert(!atomic_read(&sk->sk_wmem_alloc));
+ caif_assert(sk_unhashed(sk));
+ caif_assert(!sk->sk_socket);
+ if (!sock_flag(sk, SOCK_DEAD)) {
+ pr_info("Attempt to release alive CAIF socket: %p\n", sk);
+ return;
+ }
+ sk_stream_kill_queues(&cf_sk->sk);
+ dbfs_atomic_dec(&cnt.caif_nr_socks);
+}
+
+static int caif_create(struct net *net, struct socket *sock, int protocol,
+ int kern)
+{
+ struct sock *sk = NULL;
+ struct caifsock *cf_sk = NULL;
+ static struct proto prot = {.name = "PF_CAIF",
+ .owner = THIS_MODULE,
+ .obj_size = sizeof(struct caifsock),
+ };
+
+ if (!capable(CAP_SYS_ADMIN) && !capable(CAP_NET_ADMIN))
+ return -EPERM;
+ /*
+ * The sock->type specifies the socket type to use.
+ * The CAIF socket is a packet stream in the sense
+ * that it is packet based. CAIF trusts the reliability
+ * of the link, no resending is implemented.
+ */
+ if (sock->type == SOCK_SEQPACKET)
+ sock->ops = &caif_seqpacket_ops;
+ else if (sock->type == SOCK_STREAM)
+ sock->ops = &caif_stream_ops;
+ else
+ return -ESOCKTNOSUPPORT;
+
+ if (protocol < 0 || protocol >= CAIFPROTO_MAX)
+ return -EPROTONOSUPPORT;
+ /*
+ * Set the socket state to unconnected. The socket state
+ * is really not used at all in the net/core or socket.c but the
+ * initialization makes sure that sock->state is not uninitialized.
+ */
+ sk = sk_alloc(net, PF_CAIF, GFP_KERNEL, &prot);
+ if (!sk)
+ return -ENOMEM;
+
+ cf_sk = container_of(sk, struct caifsock, sk);
+
+ /* Store the protocol */
+ sk->sk_protocol = (unsigned char) protocol;
+
+ /* Sendbuf dictates the amount of outbound packets not yet sent */
+ sk->sk_sndbuf = CAIF_DEF_SNDBUF;
+ sk->sk_rcvbuf = CAIF_DEF_RCVBUF;
+
+ /*
+ * Lock in order to try to stop someone from opening the socket
+ * too early.
+ */
+ lock_sock(&(cf_sk->sk));
+
+ /* Initialize the nozero default sock structure data. */
+ sock_init_data(sock, sk);
+ sk->sk_destruct = caif_sock_destructor;
+
+ mutex_init(&cf_sk->readlock); /* single task reading lock */
+ cf_sk->layer.ctrlcmd = caif_ctrl_cb;
+ cf_sk->sk.sk_socket->state = SS_UNCONNECTED;
+ cf_sk->sk.sk_state = CAIF_DISCONNECTED;
+
+ set_tx_flow_off(cf_sk);
+ set_rx_flow_on(cf_sk);
+
+ /* Set default options on configuration */
+ cf_sk->conn_req.priority = CAIF_PRIO_NORMAL;
+ cf_sk->conn_req.link_selector = CAIF_LINK_LOW_LATENCY;
+ cf_sk->conn_req.protocol = protocol;
+ /* Increase the number of sockets created. */
+ dbfs_atomic_inc(&cnt.caif_nr_socks);
+#ifdef CONFIG_DEBUG_FS
+ if (!IS_ERR(debugfsdir)) {
+ /* Fill in some information concerning the misc socket. */
+ snprintf(cf_sk->name, sizeof(cf_sk->name), "cfsk%d",
+ atomic_read(&cnt.caif_nr_socks));
+
+ cf_sk->debugfs_socket_dir =
+ debugfs_create_dir(cf_sk->name, debugfsdir);
+ debugfs_create_u32("sk_state", S_IRUSR | S_IWUSR,
+ cf_sk->debugfs_socket_dir,
+ (u32 *) &cf_sk->sk.sk_state);
+ debugfs_create_u32("flow_state", S_IRUSR | S_IWUSR,
+ cf_sk->debugfs_socket_dir, &cf_sk->flow_state);
+ debugfs_create_u32("sk_rmem_alloc", S_IRUSR | S_IWUSR,
+ cf_sk->debugfs_socket_dir,
+ (u32 *) &cf_sk->sk.sk_rmem_alloc);
+ debugfs_create_u32("sk_wmem_alloc", S_IRUSR | S_IWUSR,
+ cf_sk->debugfs_socket_dir,
+ (u32 *) &cf_sk->sk.sk_wmem_alloc);
+ debugfs_create_u32("identity", S_IRUSR | S_IWUSR,
+ cf_sk->debugfs_socket_dir,
+ (u32 *) &cf_sk->layer.id);
+ }
+#endif
+ release_sock(&cf_sk->sk);
+ return 0;
+}
+
+
+static struct net_proto_family caif_family_ops = {
+ .family = PF_CAIF,
+ .create = caif_create,
+ .owner = THIS_MODULE,
+};
+
+int af_caif_init(void)
+{
+ int err = sock_register(&caif_family_ops);
+ if (!err)
+ return err;
+ return 0;
+}
+
+static int __init caif_sktinit_module(void)
+{
+#ifdef CONFIG_DEBUG_FS
+ debugfsdir = debugfs_create_dir("caif_sk", NULL);
+ if (!IS_ERR(debugfsdir)) {
+ debugfs_create_u32("num_sockets", S_IRUSR | S_IWUSR,
+ debugfsdir,
+ (u32 *) &cnt.caif_nr_socks);
+ debugfs_create_u32("num_connect_req", S_IRUSR | S_IWUSR,
+ debugfsdir,
+ (u32 *) &cnt.num_connect_req);
+ debugfs_create_u32("num_connect_resp", S_IRUSR | S_IWUSR,
+ debugfsdir,
+ (u32 *) &cnt.num_connect_resp);
+ debugfs_create_u32("num_connect_fail_resp", S_IRUSR | S_IWUSR,
+ debugfsdir,
+ (u32 *) &cnt.num_connect_fail_resp);
+ debugfs_create_u32("num_disconnect", S_IRUSR | S_IWUSR,
+ debugfsdir,
+ (u32 *) &cnt.num_disconnect);
+ debugfs_create_u32("num_remote_shutdown_ind",
+ S_IRUSR | S_IWUSR, debugfsdir,
+ (u32 *) &cnt.num_remote_shutdown_ind);
+ debugfs_create_u32("num_tx_flow_off_ind", S_IRUSR | S_IWUSR,
+ debugfsdir,
+ (u32 *) &cnt.num_tx_flow_off_ind);
+ debugfs_create_u32("num_tx_flow_on_ind", S_IRUSR | S_IWUSR,
+ debugfsdir,
+ (u32 *) &cnt.num_tx_flow_on_ind);
+ debugfs_create_u32("num_rx_flow_off", S_IRUSR | S_IWUSR,
+ debugfsdir,
+ (u32 *) &cnt.num_rx_flow_off);
+ debugfs_create_u32("num_rx_flow_on", S_IRUSR | S_IWUSR,
+ debugfsdir,
+ (u32 *) &cnt.num_rx_flow_on);
+ }
+#endif
+ return af_caif_init();
+}
+
+static void __exit caif_sktexit_module(void)
+{
+ sock_unregister(PF_CAIF);
+ if (debugfsdir != NULL)
+ debugfs_remove_recursive(debugfsdir);
+}
+module_init(caif_sktinit_module);
+module_exit(caif_sktexit_module);
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