Bluetooth: Fix issues where sk_sleep() helper is needed now
[pandora-kernel.git] / net / bluetooth / l2cap.c
index 5a5203f..673a368 100644 (file)
@@ -68,10 +68,14 @@ static u8 l2cap_fixed_chan[8] = { 0x02, };
 
 static const struct proto_ops l2cap_sock_ops;
 
+static struct workqueue_struct *_busy_wq;
+
 static struct bt_sock_list l2cap_sk_list = {
        .lock = __RW_LOCK_UNLOCKED(l2cap_sk_list.lock)
 };
 
+static void l2cap_busy_work(struct work_struct *work);
+
 static void __l2cap_sock_close(struct sock *sk, int reason);
 static void l2cap_sock_close(struct sock *sk);
 static void l2cap_sock_kill(struct sock *sk);
@@ -330,19 +334,19 @@ static inline u8 l2cap_get_ident(struct l2cap_conn *conn)
        return id;
 }
 
-static inline int l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, void *data)
+static inline void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len, void *data)
 {
        struct sk_buff *skb = l2cap_build_cmd(conn, code, ident, len, data);
 
        BT_DBG("code 0x%2.2x", code);
 
        if (!skb)
-               return -ENOMEM;
+               return;
 
-       return hci_send_acl(conn->hcon, skb, 0);
+       hci_send_acl(conn->hcon, skb, 0);
 }
 
-static inline int l2cap_send_sframe(struct l2cap_pinfo *pi, u16 control)
+static inline void l2cap_send_sframe(struct l2cap_pinfo *pi, u16 control)
 {
        struct sk_buff *skb;
        struct l2cap_hdr *lh;
@@ -369,7 +373,7 @@ static inline int l2cap_send_sframe(struct l2cap_pinfo *pi, u16 control)
 
        skb = bt_skb_alloc(count, GFP_ATOMIC);
        if (!skb)
-               return -ENOMEM;
+               return;
 
        lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
        lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
@@ -381,19 +385,20 @@ static inline int l2cap_send_sframe(struct l2cap_pinfo *pi, u16 control)
                put_unaligned_le16(fcs, skb_put(skb, 2));
        }
 
-       return hci_send_acl(pi->conn->hcon, skb, 0);
+       hci_send_acl(pi->conn->hcon, skb, 0);
 }
 
-static inline int l2cap_send_rr_or_rnr(struct l2cap_pinfo *pi, u16 control)
+static inline void l2cap_send_rr_or_rnr(struct l2cap_pinfo *pi, u16 control)
 {
-       if (pi->conn_state & L2CAP_CONN_LOCAL_BUSY)
+       if (pi->conn_state & L2CAP_CONN_LOCAL_BUSY) {
                control |= L2CAP_SUPER_RCV_NOT_READY;
-       else
+               pi->conn_state |= L2CAP_CONN_RNR_SENT;
+       } else
                control |= L2CAP_SUPER_RCV_READY;
 
        control |= pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT;
 
-       return l2cap_send_sframe(pi, control);
+       l2cap_send_sframe(pi, control);
 }
 
 static void l2cap_do_start(struct sock *sk)
@@ -816,6 +821,7 @@ static void l2cap_sock_init(struct sock *sk, struct sock *parent)
        pi->flush_to = L2CAP_DEFAULT_FLUSH_TO;
        skb_queue_head_init(TX_QUEUE(sk));
        skb_queue_head_init(SREJ_QUEUE(sk));
+       skb_queue_head_init(BUSY_QUEUE(sk));
        INIT_LIST_HEAD(SREJ_LIST(sk));
 }
 
@@ -1236,6 +1242,37 @@ static int l2cap_sock_getname(struct socket *sock, struct sockaddr *addr, int *l
        return 0;
 }
 
+static int __l2cap_wait_ack(struct sock *sk)
+{
+       DECLARE_WAITQUEUE(wait, current);
+       int err = 0;
+       int timeo = HZ/5;
+
+       add_wait_queue(sk_sleep(sk), &wait);
+       while ((l2cap_pi(sk)->unacked_frames > 0 && l2cap_pi(sk)->conn)) {
+               set_current_state(TASK_INTERRUPTIBLE);
+
+               if (!timeo)
+                       timeo = HZ/5;
+
+               if (signal_pending(current)) {
+                       err = sock_intr_errno(timeo);
+                       break;
+               }
+
+               release_sock(sk);
+               timeo = schedule_timeout(timeo);
+               lock_sock(sk);
+
+               err = sock_error(sk);
+               if (err)
+                       break;
+       }
+       set_current_state(TASK_RUNNING);
+       remove_wait_queue(sk_sleep(sk), &wait);
+       return err;
+}
+
 static void l2cap_monitor_timeout(unsigned long arg)
 {
        struct sock *sk = (void *) arg;
@@ -1289,18 +1326,13 @@ static void l2cap_drop_acked_frames(struct sock *sk)
        return;
 }
 
-static inline int l2cap_do_send(struct sock *sk, struct sk_buff *skb)
+static inline void l2cap_do_send(struct sock *sk, struct sk_buff *skb)
 {
        struct l2cap_pinfo *pi = l2cap_pi(sk);
-       int err;
 
        BT_DBG("sk %p, skb %p len %d", sk, skb, skb->len);
 
-       err = hci_send_acl(pi->conn->hcon, skb, 0);
-       if (err < 0)
-               kfree_skb(skb);
-
-       return err;
+       hci_send_acl(pi->conn->hcon, skb, 0);
 }
 
 static int l2cap_streaming_send(struct sock *sk)
@@ -1308,7 +1340,6 @@ static int l2cap_streaming_send(struct sock *sk)
        struct sk_buff *skb, *tx_skb;
        struct l2cap_pinfo *pi = l2cap_pi(sk);
        u16 control, fcs;
-       int err;
 
        while ((skb = sk->sk_send_head)) {
                tx_skb = skb_clone(skb, GFP_ATOMIC);
@@ -1322,11 +1353,7 @@ static int l2cap_streaming_send(struct sock *sk)
                        put_unaligned_le16(fcs, tx_skb->data + tx_skb->len - 2);
                }
 
-               err = l2cap_do_send(sk, tx_skb);
-               if (err < 0) {
-                       l2cap_send_disconn_req(pi->conn, sk);
-                       return err;
-               }
+               l2cap_do_send(sk, tx_skb);
 
                pi->next_tx_seq = (pi->next_tx_seq + 1) % 64;
 
@@ -1341,48 +1368,44 @@ static int l2cap_streaming_send(struct sock *sk)
        return 0;
 }
 
-static int l2cap_retransmit_frame(struct sock *sk, u8 tx_seq)
+static void l2cap_retransmit_one_frame(struct sock *sk, u8 tx_seq)
 {
        struct l2cap_pinfo *pi = l2cap_pi(sk);
        struct sk_buff *skb, *tx_skb;
        u16 control, fcs;
-       int err;
 
        skb = skb_peek(TX_QUEUE(sk));
-       do {
-               if (bt_cb(skb)->tx_seq != tx_seq) {
-                       if (skb_queue_is_last(TX_QUEUE(sk), skb))
-                               break;
-                       skb = skb_queue_next(TX_QUEUE(sk), skb);
-                       continue;
-               }
+       if (!skb)
+               return;
 
-               if (pi->remote_max_tx &&
-                               bt_cb(skb)->retries == pi->remote_max_tx) {
-                       l2cap_send_disconn_req(pi->conn, sk);
+       do {
+               if (bt_cb(skb)->tx_seq == tx_seq)
                        break;
-               }
 
-               tx_skb = skb_clone(skb, GFP_ATOMIC);
-               bt_cb(skb)->retries++;
-               control = get_unaligned_le16(tx_skb->data + L2CAP_HDR_SIZE);
-               control |= (pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT)
-                               | (tx_seq << L2CAP_CTRL_TXSEQ_SHIFT);
-               put_unaligned_le16(control, tx_skb->data + L2CAP_HDR_SIZE);
+               if (skb_queue_is_last(TX_QUEUE(sk), skb))
+                       return;
 
-               if (pi->fcs == L2CAP_FCS_CRC16) {
-                       fcs = crc16(0, (u8 *)tx_skb->data, tx_skb->len - 2);
-                       put_unaligned_le16(fcs, tx_skb->data + tx_skb->len - 2);
-               }
+       } while ((skb = skb_queue_next(TX_QUEUE(sk), skb)));
 
-               err = l2cap_do_send(sk, tx_skb);
-               if (err < 0) {
-                       l2cap_send_disconn_req(pi->conn, sk);
-                       return err;
-               }
-               break;
-       } while(1);
-       return 0;
+       if (pi->remote_max_tx &&
+                       bt_cb(skb)->retries == pi->remote_max_tx) {
+               l2cap_send_disconn_req(pi->conn, sk);
+               return;
+       }
+
+       tx_skb = skb_clone(skb, GFP_ATOMIC);
+       bt_cb(skb)->retries++;
+       control = get_unaligned_le16(tx_skb->data + L2CAP_HDR_SIZE);
+       control |= (pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT)
+                       | (tx_seq << L2CAP_CTRL_TXSEQ_SHIFT);
+       put_unaligned_le16(control, tx_skb->data + L2CAP_HDR_SIZE);
+
+       if (pi->fcs == L2CAP_FCS_CRC16) {
+               fcs = crc16(0, (u8 *)tx_skb->data, tx_skb->len - 2);
+               put_unaligned_le16(fcs, tx_skb->data + tx_skb->len - 2);
+       }
+
+       l2cap_do_send(sk, tx_skb);
 }
 
 static int l2cap_ertm_send(struct sock *sk)
@@ -1390,7 +1413,7 @@ static int l2cap_ertm_send(struct sock *sk)
        struct sk_buff *skb, *tx_skb;
        struct l2cap_pinfo *pi = l2cap_pi(sk);
        u16 control, fcs;
-       int err, nsent = 0;
+       int nsent = 0;
 
        if (pi->conn_state & L2CAP_CONN_WAIT_F)
                return 0;
@@ -1423,11 +1446,8 @@ static int l2cap_ertm_send(struct sock *sk)
                        put_unaligned_le16(fcs, skb->data + tx_skb->len - 2);
                }
 
-               err = l2cap_do_send(sk, tx_skb);
-               if (err < 0) {
-                       l2cap_send_disconn_req(pi->conn, sk);
-                       return err;
-               }
+               l2cap_do_send(sk, tx_skb);
+
                __mod_retrans_timer();
 
                bt_cb(skb)->tx_seq = pi->next_tx_seq;
@@ -1447,24 +1467,51 @@ static int l2cap_ertm_send(struct sock *sk)
        return nsent;
 }
 
-static int l2cap_send_ack(struct l2cap_pinfo *pi)
+static int l2cap_retransmit_frames(struct sock *sk)
+{
+       struct l2cap_pinfo *pi = l2cap_pi(sk);
+       int ret;
+
+       spin_lock_bh(&pi->send_lock);
+
+       if (!skb_queue_empty(TX_QUEUE(sk)))
+               sk->sk_send_head = TX_QUEUE(sk)->next;
+
+       pi->next_tx_seq = pi->expected_ack_seq;
+       ret = l2cap_ertm_send(sk);
+
+       spin_unlock_bh(&pi->send_lock);
+
+       return ret;
+}
+
+static void l2cap_send_ack(struct l2cap_pinfo *pi)
 {
        struct sock *sk = (struct sock *)pi;
        u16 control = 0;
+       int nframes;
 
        control |= pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT;
 
        if (pi->conn_state & L2CAP_CONN_LOCAL_BUSY) {
                control |= L2CAP_SUPER_RCV_NOT_READY;
-               return l2cap_send_sframe(pi, control);
-       } else if (l2cap_ertm_send(sk) == 0) {
-               control |= L2CAP_SUPER_RCV_READY;
-               return l2cap_send_sframe(pi, control);
+               pi->conn_state |= L2CAP_CONN_RNR_SENT;
+               l2cap_send_sframe(pi, control);
+               return;
        }
-       return 0;
+
+       spin_lock_bh(&pi->send_lock);
+       nframes = l2cap_ertm_send(sk);
+       spin_unlock_bh(&pi->send_lock);
+
+       if (nframes > 0)
+               return;
+
+       control |= L2CAP_SUPER_RCV_READY;
+       l2cap_send_sframe(pi, control);
 }
 
-static int l2cap_send_srejtail(struct sock *sk)
+static void l2cap_send_srejtail(struct sock *sk)
 {
        struct srej_list *tail;
        u16 control;
@@ -1476,8 +1523,6 @@ static int l2cap_send_srejtail(struct sock *sk)
        control |= tail->tx_seq << L2CAP_CTRL_REQSEQ_SHIFT;
 
        l2cap_send_sframe(l2cap_pi(sk), control);
-
-       return 0;
 }
 
 static inline int l2cap_skbuff_fromiovec(struct sock *sk, struct msghdr *msg, int len, int count, struct sk_buff *skb)
@@ -1622,7 +1667,7 @@ static inline int l2cap_sar_segment_sdu(struct sock *sk, struct msghdr *msg, siz
        u16 control;
        size_t size = 0;
 
-       __skb_queue_head_init(&sar_queue);
+       skb_queue_head_init(&sar_queue);
        control = L2CAP_SDU_START;
        skb = l2cap_create_iframe_pdu(sk, msg, pi->remote_mps, control, len);
        if (IS_ERR(skb))
@@ -1654,8 +1699,10 @@ static inline int l2cap_sar_segment_sdu(struct sock *sk, struct msghdr *msg, siz
                size += buflen;
        }
        skb_queue_splice_tail(&sar_queue, TX_QUEUE(sk));
+       spin_lock_bh(&pi->send_lock);
        if (sk->sk_send_head == NULL)
                sk->sk_send_head = sar_queue.next;
+       spin_unlock_bh(&pi->send_lock);
 
        return size;
 }
@@ -1687,10 +1734,12 @@ static int l2cap_sock_sendmsg(struct kiocb *iocb, struct socket *sock, struct ms
        /* Connectionless channel */
        if (sk->sk_type == SOCK_DGRAM) {
                skb = l2cap_create_connless_pdu(sk, msg, len);
-               if (IS_ERR(skb))
+               if (IS_ERR(skb)) {
                        err = PTR_ERR(skb);
-               else
-                       err = l2cap_do_send(sk, skb);
+               } else {
+                       l2cap_do_send(sk, skb);
+                       err = len;
+               }
                goto done;
        }
 
@@ -1709,9 +1758,8 @@ static int l2cap_sock_sendmsg(struct kiocb *iocb, struct socket *sock, struct ms
                        goto done;
                }
 
-               err = l2cap_do_send(sk, skb);
-               if (!err)
-                       err = len;
+               l2cap_do_send(sk, skb);
+               err = len;
                break;
 
        case L2CAP_MODE_ERTM:
@@ -1725,8 +1773,15 @@ static int l2cap_sock_sendmsg(struct kiocb *iocb, struct socket *sock, struct ms
                                goto done;
                        }
                        __skb_queue_tail(TX_QUEUE(sk), skb);
+
+                       if (pi->mode == L2CAP_MODE_ERTM)
+                               spin_lock_bh(&pi->send_lock);
+
                        if (sk->sk_send_head == NULL)
                                sk->sk_send_head = skb;
+
+                       if (pi->mode == L2CAP_MODE_ERTM)
+                               spin_unlock_bh(&pi->send_lock);
                } else {
                /* Segment SDU into multiples PDUs */
                        err = l2cap_sar_segment_sdu(sk, msg, len);
@@ -1734,10 +1789,13 @@ static int l2cap_sock_sendmsg(struct kiocb *iocb, struct socket *sock, struct ms
                                goto done;
                }
 
-               if (pi->mode == L2CAP_MODE_STREAMING)
+               if (pi->mode == L2CAP_MODE_STREAMING) {
                        err = l2cap_streaming_send(sk);
-               else
+               } else {
+                       spin_lock_bh(&pi->send_lock);
                        err = l2cap_ertm_send(sk);
+                       spin_unlock_bh(&pi->send_lock);
+               }
 
                if (err >= 0)
                        err = len;
@@ -2070,6 +2128,9 @@ static int l2cap_sock_shutdown(struct socket *sock, int how)
 
        lock_sock(sk);
        if (!sk->sk_shutdown) {
+               if (l2cap_pi(sk)->mode == L2CAP_MODE_ERTM)
+                       err = __l2cap_wait_ack(sk);
+
                sk->sk_shutdown = SHUTDOWN_MASK;
                l2cap_sock_clear_timer(sk);
                __l2cap_sock_close(sk, 0);
@@ -2297,6 +2358,10 @@ static inline void l2cap_ertm_init(struct sock *sk)
                        l2cap_ack_timeout, (unsigned long) sk);
 
        __skb_queue_head_init(SREJ_QUEUE(sk));
+       __skb_queue_head_init(BUSY_QUEUE(sk));
+       spin_lock_init(&l2cap_pi(sk)->send_lock);
+
+       INIT_WORK(&l2cap_pi(sk)->busy_work, l2cap_busy_work);
 }
 
 static int l2cap_mode_supported(__u8 mode, __u32 feat_mask)
@@ -3064,6 +3129,7 @@ static inline int l2cap_disconnect_req(struct l2cap_conn *conn, struct l2cap_cmd
 
        if (l2cap_pi(sk)->mode == L2CAP_MODE_ERTM) {
                skb_queue_purge(SREJ_QUEUE(sk));
+               skb_queue_purge(BUSY_QUEUE(sk));
                del_timer(&l2cap_pi(sk)->retrans_timer);
                del_timer(&l2cap_pi(sk)->monitor_timer);
                del_timer(&l2cap_pi(sk)->ack_timer);
@@ -3095,6 +3161,7 @@ static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn, struct l2cap_cmd
 
        if (l2cap_pi(sk)->mode == L2CAP_MODE_ERTM) {
                skb_queue_purge(SREJ_QUEUE(sk));
+               skb_queue_purge(BUSY_QUEUE(sk));
                del_timer(&l2cap_pi(sk)->retrans_timer);
                del_timer(&l2cap_pi(sk)->monitor_timer);
                del_timer(&l2cap_pi(sk)->ack_timer);
@@ -3305,13 +3372,18 @@ static inline void l2cap_send_i_or_rr_or_rnr(struct sock *sk)
        if (pi->conn_state & L2CAP_CONN_LOCAL_BUSY) {
                control |= L2CAP_SUPER_RCV_NOT_READY | L2CAP_CTRL_FINAL;
                l2cap_send_sframe(pi, control);
+               pi->conn_state |= L2CAP_CONN_RNR_SENT;
                pi->conn_state &= ~L2CAP_CONN_SEND_FBIT;
        }
 
        if (pi->conn_state & L2CAP_CONN_REMOTE_BUSY && pi->unacked_frames > 0)
                __mod_retrans_timer();
 
+       pi->conn_state &= ~L2CAP_CONN_REMOTE_BUSY;
+
+       spin_lock_bh(&pi->send_lock);
        l2cap_ertm_send(sk);
+       spin_unlock_bh(&pi->send_lock);
 
        if (!(pi->conn_state & L2CAP_CONN_LOCAL_BUSY) &&
                        pi->frames_sent == 0) {
@@ -3320,7 +3392,7 @@ static inline void l2cap_send_i_or_rr_or_rnr(struct sock *sk)
        }
 }
 
-static void l2cap_add_to_srej_queue(struct sock *sk, struct sk_buff *skb, u8 tx_seq, u8 sar)
+static int l2cap_add_to_srej_queue(struct sock *sk, struct sk_buff *skb, u8 tx_seq, u8 sar)
 {
        struct sk_buff *next_skb;
 
@@ -3330,13 +3402,16 @@ static void l2cap_add_to_srej_queue(struct sock *sk, struct sk_buff *skb, u8 tx_
        next_skb = skb_peek(SREJ_QUEUE(sk));
        if (!next_skb) {
                __skb_queue_tail(SREJ_QUEUE(sk), skb);
-               return;
+               return 0;
        }
 
        do {
+               if (bt_cb(next_skb)->tx_seq == tx_seq)
+                       return -EINVAL;
+
                if (bt_cb(next_skb)->tx_seq > tx_seq) {
                        __skb_queue_before(SREJ_QUEUE(sk), next_skb, skb);
-                       return;
+                       return 0;
                }
 
                if (skb_queue_is_last(SREJ_QUEUE(sk), next_skb))
@@ -3345,14 +3420,238 @@ static void l2cap_add_to_srej_queue(struct sock *sk, struct sk_buff *skb, u8 tx_
        } while ((next_skb = skb_queue_next(SREJ_QUEUE(sk), next_skb)));
 
        __skb_queue_tail(SREJ_QUEUE(sk), skb);
+
+       return 0;
 }
 
-static int l2cap_sar_reassembly_sdu(struct sock *sk, struct sk_buff *skb, u16 control)
+static int l2cap_ertm_reassembly_sdu(struct sock *sk, struct sk_buff *skb, u16 control)
+{
+       struct l2cap_pinfo *pi = l2cap_pi(sk);
+       struct sk_buff *_skb;
+       int err;
+
+       switch (control & L2CAP_CTRL_SAR) {
+       case L2CAP_SDU_UNSEGMENTED:
+               if (pi->conn_state & L2CAP_CONN_SAR_SDU)
+                       goto drop;
+
+               err = sock_queue_rcv_skb(sk, skb);
+               if (!err)
+                       return err;
+
+               break;
+
+       case L2CAP_SDU_START:
+               if (pi->conn_state & L2CAP_CONN_SAR_SDU)
+                       goto drop;
+
+               pi->sdu_len = get_unaligned_le16(skb->data);
+
+               if (pi->sdu_len > pi->imtu)
+                       goto disconnect;
+
+               pi->sdu = bt_skb_alloc(pi->sdu_len, GFP_ATOMIC);
+               if (!pi->sdu)
+                       return -ENOMEM;
+
+               /* pull sdu_len bytes only after alloc, because of Local Busy
+                * condition we have to be sure that this will be executed
+                * only once, i.e., when alloc does not fail */
+               skb_pull(skb, 2);
+
+               memcpy(skb_put(pi->sdu, skb->len), skb->data, skb->len);
+
+               pi->conn_state |= L2CAP_CONN_SAR_SDU;
+               pi->partial_sdu_len = skb->len;
+               break;
+
+       case L2CAP_SDU_CONTINUE:
+               if (!(pi->conn_state & L2CAP_CONN_SAR_SDU))
+                       goto disconnect;
+
+               if (!pi->sdu)
+                       goto disconnect;
+
+               pi->partial_sdu_len += skb->len;
+               if (pi->partial_sdu_len > pi->sdu_len)
+                       goto drop;
+
+               memcpy(skb_put(pi->sdu, skb->len), skb->data, skb->len);
+
+               break;
+
+       case L2CAP_SDU_END:
+               if (!(pi->conn_state & L2CAP_CONN_SAR_SDU))
+                       goto disconnect;
+
+               if (!pi->sdu)
+                       goto disconnect;
+
+               if (!(pi->conn_state & L2CAP_CONN_SAR_RETRY)) {
+                       pi->partial_sdu_len += skb->len;
+
+                       if (pi->partial_sdu_len > pi->imtu)
+                               goto drop;
+
+                       if (pi->partial_sdu_len != pi->sdu_len)
+                               goto drop;
+
+                       memcpy(skb_put(pi->sdu, skb->len), skb->data, skb->len);
+               }
+
+               _skb = skb_clone(pi->sdu, GFP_ATOMIC);
+               if (!_skb) {
+                       pi->conn_state |= L2CAP_CONN_SAR_RETRY;
+                       return -ENOMEM;
+               }
+
+               err = sock_queue_rcv_skb(sk, _skb);
+               if (err < 0) {
+                       kfree_skb(_skb);
+                       pi->conn_state |= L2CAP_CONN_SAR_RETRY;
+                       return err;
+               }
+
+               pi->conn_state &= ~L2CAP_CONN_SAR_RETRY;
+               pi->conn_state &= ~L2CAP_CONN_SAR_SDU;
+
+               kfree_skb(pi->sdu);
+               break;
+       }
+
+       kfree_skb(skb);
+       return 0;
+
+drop:
+       kfree_skb(pi->sdu);
+       pi->sdu = NULL;
+
+disconnect:
+       l2cap_send_disconn_req(pi->conn, sk);
+       kfree_skb(skb);
+       return 0;
+}
+
+static void l2cap_busy_work(struct work_struct *work)
+{
+       DECLARE_WAITQUEUE(wait, current);
+       struct l2cap_pinfo *pi =
+               container_of(work, struct l2cap_pinfo, busy_work);
+       struct sock *sk = (struct sock *)pi;
+       int n_tries = 0, timeo = HZ/5, err;
+       struct sk_buff *skb;
+       u16 control;
+
+       lock_sock(sk);
+
+       add_wait_queue(sk_sleep(sk), &wait);
+       while ((skb = skb_peek(BUSY_QUEUE(sk)))) {
+               set_current_state(TASK_INTERRUPTIBLE);
+
+               if (n_tries++ > L2CAP_LOCAL_BUSY_TRIES) {
+                       err = -EBUSY;
+                       l2cap_send_disconn_req(pi->conn, sk);
+                       goto done;
+               }
+
+               if (!timeo)
+                       timeo = HZ/5;
+
+               if (signal_pending(current)) {
+                       err = sock_intr_errno(timeo);
+                       goto done;
+               }
+
+               release_sock(sk);
+               timeo = schedule_timeout(timeo);
+               lock_sock(sk);
+
+               err = sock_error(sk);
+               if (err)
+                       goto done;
+
+               while ((skb = skb_dequeue(BUSY_QUEUE(sk)))) {
+                       control = bt_cb(skb)->sar << L2CAP_CTRL_SAR_SHIFT;
+                       err = l2cap_ertm_reassembly_sdu(sk, skb, control);
+                       if (err < 0) {
+                               skb_queue_head(BUSY_QUEUE(sk), skb);
+                               break;
+                       }
+
+                       pi->buffer_seq = (pi->buffer_seq + 1) % 64;
+               }
+
+               if (!skb)
+                       break;
+       }
+
+       if (!(pi->conn_state & L2CAP_CONN_RNR_SENT))
+               goto done;
+
+       control = pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT;
+       control |= L2CAP_SUPER_RCV_READY | L2CAP_CTRL_POLL;
+       l2cap_send_sframe(pi, control);
+       l2cap_pi(sk)->retry_count = 1;
+
+       del_timer(&pi->retrans_timer);
+       __mod_monitor_timer();
+
+       l2cap_pi(sk)->conn_state |= L2CAP_CONN_WAIT_F;
+
+done:
+       pi->conn_state &= ~L2CAP_CONN_LOCAL_BUSY;
+       pi->conn_state &= ~L2CAP_CONN_RNR_SENT;
+
+       set_current_state(TASK_RUNNING);
+       remove_wait_queue(sk_sleep(sk), &wait);
+
+       release_sock(sk);
+}
+
+static int l2cap_push_rx_skb(struct sock *sk, struct sk_buff *skb, u16 control)
+{
+       struct l2cap_pinfo *pi = l2cap_pi(sk);
+       int sctrl, err;
+
+       if (pi->conn_state & L2CAP_CONN_LOCAL_BUSY) {
+               bt_cb(skb)->sar = control >> L2CAP_CTRL_SAR_SHIFT;
+               __skb_queue_tail(BUSY_QUEUE(sk), skb);
+               return -EBUSY;
+       }
+
+       err = l2cap_ertm_reassembly_sdu(sk, skb, control);
+       if (err >= 0) {
+               pi->buffer_seq = (pi->buffer_seq + 1) % 64;
+               return err;
+       }
+
+       /* Busy Condition */
+       pi->conn_state |= L2CAP_CONN_LOCAL_BUSY;
+       bt_cb(skb)->sar = control >> L2CAP_CTRL_SAR_SHIFT;
+       __skb_queue_tail(BUSY_QUEUE(sk), skb);
+
+       sctrl = pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT;
+       sctrl |= L2CAP_SUPER_RCV_NOT_READY;
+       l2cap_send_sframe(pi, sctrl);
+
+       pi->conn_state |= L2CAP_CONN_RNR_SENT;
+
+       queue_work(_busy_wq, &pi->busy_work);
+
+       return err;
+}
+
+static int l2cap_streaming_reassembly_sdu(struct sock *sk, struct sk_buff *skb, u16 control)
 {
        struct l2cap_pinfo *pi = l2cap_pi(sk);
        struct sk_buff *_skb;
        int err = -EINVAL;
 
+       /*
+        * TODO: We have to notify the userland if some data is lost with the
+        * Streaming Mode.
+        */
+
        switch (control & L2CAP_CTRL_SAR) {
        case L2CAP_SDU_UNSEGMENTED:
                if (pi->conn_state & L2CAP_CONN_SAR_SDU) {
@@ -3447,7 +3746,7 @@ static void l2cap_check_srej_gap(struct sock *sk, u8 tx_seq)
 
                skb = skb_dequeue(SREJ_QUEUE(sk));
                control = bt_cb(skb)->sar << L2CAP_CTRL_SAR_SHIFT;
-               l2cap_sar_reassembly_sdu(sk, skb, control);
+               l2cap_ertm_reassembly_sdu(sk, skb, control);
                l2cap_pi(sk)->buffer_seq_srej =
                        (l2cap_pi(sk)->buffer_seq_srej + 1) % 64;
                tx_seq++;
@@ -3498,12 +3797,14 @@ static inline int l2cap_data_channel_iframe(struct sock *sk, u16 rx_control, str
        u8 tx_seq = __get_txseq(rx_control);
        u8 req_seq = __get_reqseq(rx_control);
        u8 sar = rx_control >> L2CAP_CTRL_SAR_SHIFT;
+       u8 tx_seq_offset, expected_tx_seq_offset;
        int num_to_ack = (pi->tx_win/6) + 1;
        int err = 0;
 
        BT_DBG("sk %p rx_control 0x%4.4x len %d", sk, rx_control, skb->len);
 
-       if (L2CAP_CTRL_FINAL & rx_control) {
+       if (L2CAP_CTRL_FINAL & rx_control &&
+                       l2cap_pi(sk)->conn_state & L2CAP_CONN_WAIT_F) {
                del_timer(&pi->monitor_timer);
                if (pi->unacked_frames > 0)
                        __mod_retrans_timer();
@@ -3516,6 +3817,19 @@ static inline int l2cap_data_channel_iframe(struct sock *sk, u16 rx_control, str
        if (tx_seq == pi->expected_tx_seq)
                goto expected;
 
+       tx_seq_offset = (tx_seq - pi->buffer_seq) % 64;
+       if (tx_seq_offset < 0)
+               tx_seq_offset += 64;
+
+       /* invalid tx_seq */
+       if (tx_seq_offset >= pi->tx_win) {
+               l2cap_send_disconn_req(pi->conn, sk);
+               goto drop;
+       }
+
+       if (pi->conn_state == L2CAP_CONN_LOCAL_BUSY)
+               goto drop;
+
        if (pi->conn_state & L2CAP_CONN_SREJ_SENT) {
                struct srej_list *first;
 
@@ -3535,7 +3849,10 @@ static inline int l2cap_data_channel_iframe(struct sock *sk, u16 rx_control, str
                        }
                } else {
                        struct srej_list *l;
-                       l2cap_add_to_srej_queue(sk, skb, tx_seq, sar);
+
+                       /* duplicated tx_seq */
+                       if (l2cap_add_to_srej_queue(sk, skb, tx_seq, sar) < 0)
+                               goto drop;
 
                        list_for_each_entry(l, SREJ_LIST(sk), list) {
                                if (l->tx_seq == tx_seq) {
@@ -3546,12 +3863,22 @@ static inline int l2cap_data_channel_iframe(struct sock *sk, u16 rx_control, str
                        l2cap_send_srejframe(sk, tx_seq);
                }
        } else {
+               expected_tx_seq_offset =
+                       (pi->expected_tx_seq - pi->buffer_seq) % 64;
+               if (expected_tx_seq_offset < 0)
+                       expected_tx_seq_offset += 64;
+
+               /* duplicated tx_seq */
+               if (tx_seq_offset < expected_tx_seq_offset)
+                       goto drop;
+
                pi->conn_state |= L2CAP_CONN_SREJ_SENT;
 
                INIT_LIST_HEAD(SREJ_LIST(sk));
                pi->buffer_seq_srej = pi->buffer_seq;
 
                __skb_queue_head_init(SREJ_QUEUE(sk));
+               __skb_queue_head_init(BUSY_QUEUE(sk));
                l2cap_add_to_srej_queue(sk, skb, tx_seq, sar);
 
                pi->conn_state |= L2CAP_CONN_SEND_PBIT;
@@ -3573,19 +3900,13 @@ expected:
        if (rx_control & L2CAP_CTRL_FINAL) {
                if (pi->conn_state & L2CAP_CONN_REJ_ACT)
                        pi->conn_state &= ~L2CAP_CONN_REJ_ACT;
-               else {
-                       if (!skb_queue_empty(TX_QUEUE(sk)))
-                               sk->sk_send_head = TX_QUEUE(sk)->next;
-                       pi->next_tx_seq = pi->expected_ack_seq;
-                       l2cap_ertm_send(sk);
-               }
+               else
+                       l2cap_retransmit_frames(sk);
        }
 
-       pi->buffer_seq = (pi->buffer_seq + 1) % 64;
-
-       err = l2cap_sar_reassembly_sdu(sk, skb, rx_control);
+       err = l2cap_push_rx_skb(sk, skb, rx_control);
        if (err < 0)
-               return err;
+               return 0;
 
        __mod_ack_timer();
 
@@ -3594,6 +3915,10 @@ expected:
                l2cap_send_ack(pi);
 
        return 0;
+
+drop:
+       kfree_skb(skb);
+       return 0;
 }
 
 static inline void l2cap_data_channel_rrframe(struct sock *sk, u16 rx_control)
@@ -3613,7 +3938,6 @@ static inline void l2cap_data_channel_rrframe(struct sock *sk, u16 rx_control)
                        l2cap_send_srejtail(sk);
                } else {
                        l2cap_send_i_or_rr_or_rnr(sk);
-                       pi->conn_state &= ~L2CAP_CONN_REMOTE_BUSY;
                }
 
        } else if (rx_control & L2CAP_CTRL_FINAL) {
@@ -3621,12 +3945,8 @@ static inline void l2cap_data_channel_rrframe(struct sock *sk, u16 rx_control)
 
                if (pi->conn_state & L2CAP_CONN_REJ_ACT)
                        pi->conn_state &= ~L2CAP_CONN_REJ_ACT;
-               else {
-                       if (!skb_queue_empty(TX_QUEUE(sk)))
-                               sk->sk_send_head = TX_QUEUE(sk)->next;
-                       pi->next_tx_seq = pi->expected_ack_seq;
-                       l2cap_ertm_send(sk);
-               }
+               else
+                       l2cap_retransmit_frames(sk);
 
        } else {
                if ((pi->conn_state & L2CAP_CONN_REMOTE_BUSY) &&
@@ -3634,10 +3954,13 @@ static inline void l2cap_data_channel_rrframe(struct sock *sk, u16 rx_control)
                        __mod_retrans_timer();
 
                pi->conn_state &= ~L2CAP_CONN_REMOTE_BUSY;
-               if (pi->conn_state & L2CAP_CONN_SREJ_SENT)
+               if (pi->conn_state & L2CAP_CONN_SREJ_SENT) {
                        l2cap_send_ack(pi);
-               else
+               } else {
+                       spin_lock_bh(&pi->send_lock);
                        l2cap_ertm_send(sk);
+                       spin_unlock_bh(&pi->send_lock);
+               }
        }
 }
 
@@ -3654,17 +3977,10 @@ static inline void l2cap_data_channel_rejframe(struct sock *sk, u16 rx_control)
        if (rx_control & L2CAP_CTRL_FINAL) {
                if (pi->conn_state & L2CAP_CONN_REJ_ACT)
                        pi->conn_state &= ~L2CAP_CONN_REJ_ACT;
-               else {
-                       if (!skb_queue_empty(TX_QUEUE(sk)))
-                               sk->sk_send_head = TX_QUEUE(sk)->next;
-                       pi->next_tx_seq = pi->expected_ack_seq;
-                       l2cap_ertm_send(sk);
-               }
+               else
+                       l2cap_retransmit_frames(sk);
        } else {
-               if (!skb_queue_empty(TX_QUEUE(sk)))
-                       sk->sk_send_head = TX_QUEUE(sk)->next;
-               pi->next_tx_seq = pi->expected_ack_seq;
-               l2cap_ertm_send(sk);
+               l2cap_retransmit_frames(sk);
 
                if (pi->conn_state & L2CAP_CONN_WAIT_F)
                        pi->conn_state |= L2CAP_CONN_REJ_ACT;
@@ -3680,8 +3996,12 @@ static inline void l2cap_data_channel_srejframe(struct sock *sk, u16 rx_control)
        if (rx_control & L2CAP_CTRL_POLL) {
                pi->expected_ack_seq = tx_seq;
                l2cap_drop_acked_frames(sk);
-               l2cap_retransmit_frame(sk, tx_seq);
+               l2cap_retransmit_one_frame(sk, tx_seq);
+
+               spin_lock_bh(&pi->send_lock);
                l2cap_ertm_send(sk);
+               spin_unlock_bh(&pi->send_lock);
+
                if (pi->conn_state & L2CAP_CONN_WAIT_F) {
                        pi->srej_save_reqseq = tx_seq;
                        pi->conn_state |= L2CAP_CONN_SREJ_ACT;
@@ -3691,9 +4011,9 @@ static inline void l2cap_data_channel_srejframe(struct sock *sk, u16 rx_control)
                                pi->srej_save_reqseq == tx_seq)
                        pi->conn_state &= ~L2CAP_CONN_SREJ_ACT;
                else
-                       l2cap_retransmit_frame(sk, tx_seq);
+                       l2cap_retransmit_one_frame(sk, tx_seq);
        } else {
-               l2cap_retransmit_frame(sk, tx_seq);
+               l2cap_retransmit_one_frame(sk, tx_seq);
                if (pi->conn_state & L2CAP_CONN_WAIT_F) {
                        pi->srej_save_reqseq = tx_seq;
                        pi->conn_state |= L2CAP_CONN_SREJ_ACT;
@@ -3727,7 +4047,8 @@ static inline int l2cap_data_channel_sframe(struct sock *sk, u16 rx_control, str
 {
        BT_DBG("sk %p rx_control 0x%4.4x len %d", sk, rx_control, skb->len);
 
-       if (L2CAP_CTRL_FINAL & rx_control) {
+       if (L2CAP_CTRL_FINAL & rx_control &&
+                       l2cap_pi(sk)->conn_state & L2CAP_CONN_WAIT_F) {
                del_timer(&l2cap_pi(sk)->monitor_timer);
                if (l2cap_pi(sk)->unacked_frames > 0)
                        __mod_retrans_timer();
@@ -3806,8 +4127,10 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk
                 * Receiver will miss it and start proper recovery
                 * procedures and ask retransmission.
                 */
-               if (len > pi->mps)
+               if (len > pi->mps) {
+                       l2cap_send_disconn_req(pi->conn, sk);
                        goto drop;
+               }
 
                if (l2cap_check_fcs(pi, skb))
                        goto drop;
@@ -3829,13 +4152,17 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk
                }
 
                if (__is_iframe(control)) {
-                       if (len < 4)
+                       if (len < 4) {
+                               l2cap_send_disconn_req(pi->conn, sk);
                                goto drop;
+                       }
 
                        l2cap_data_channel_iframe(sk, control, skb);
                } else {
-                       if (len != 0)
+                       if (len != 0) {
+                               l2cap_send_disconn_req(pi->conn, sk);
                                goto drop;
+                       }
 
                        l2cap_data_channel_sframe(sk, control, skb);
                }
@@ -3866,7 +4193,7 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk
                else
                        pi->expected_tx_seq = (tx_seq + 1) % 64;
 
-               l2cap_sar_reassembly_sdu(sk, skb, control);
+               l2cap_streaming_reassembly_sdu(sk, skb, control);
 
                goto done;
 
@@ -4285,6 +4612,10 @@ static int __init l2cap_init(void)
        if (err < 0)
                return err;
 
+       _busy_wq = create_singlethread_workqueue("l2cap");
+       if (!_busy_wq)
+               goto error;
+
        err = bt_sock_register(BTPROTO_L2CAP, &l2cap_sock_family_ops);
        if (err < 0) {
                BT_ERR("L2CAP socket registration failed");
@@ -4319,6 +4650,9 @@ static void __exit l2cap_exit(void)
 {
        debugfs_remove(l2cap_debugfs);
 
+       flush_workqueue(_busy_wq);
+       destroy_workqueue(_busy_wq);
+
        if (bt_sock_unregister(BTPROTO_L2CAP) < 0)
                BT_ERR("L2CAP socket unregistration failed");