static LIST_HEAD(chan_list);
static DEFINE_RWLOCK(chan_list_lock);
-static u16 le_max_credits = L2CAP_LE_MAX_CREDITS;
-
static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
u8 code, u8 ident, u16 dlen, void *data);
static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
chan->sdu_last_frag = NULL;
chan->sdu_len = 0;
chan->tx_credits = 0;
- chan->rx_credits = le_max_credits;
/* Derive MPS from connection MTU to stop HCI fragmentation */
chan->mps = min_t(u16, chan->imtu, chan->conn->mtu - L2CAP_HDR_SIZE);
+ /* Give enough credits for a full packet */
+ chan->rx_credits = (chan->imtu / chan->mps) + 1;
skb_queue_head_init(&chan->tx_q);
}
struct l2cap_le_credits pkt;
u16 return_credits;
- /* We return more credits to the sender only after the amount of
- * credits falls below half of the initial amount.
- */
- if (chan->rx_credits >= (le_max_credits + 1) / 2)
- return;
+ return_credits = ((chan->imtu / chan->mps) + 1) - chan->rx_credits;
- return_credits = le_max_credits - chan->rx_credits;
+ if (!return_credits)
+ return;
BT_DBG("chan %p returning %u credits to sender", chan, return_credits);
l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
}
+static int l2cap_le_recv(struct l2cap_chan *chan, struct sk_buff *skb)
+{
+ int err;
+
+ BT_DBG("SDU reassemble complete: chan %p skb->len %u", chan, skb->len);
+
+ /* Wait recv to confirm reception before updating the credits */
+ err = chan->ops->recv(chan, skb);
+
+ /* Update credits whenever an SDU is received */
+ l2cap_chan_le_send_credits(chan);
+
+ return err;
+}
+
static int l2cap_le_data_rcv(struct l2cap_chan *chan, struct sk_buff *skb)
{
int err;
chan->rx_credits--;
BT_DBG("rx_credits %u -> %u", chan->rx_credits + 1, chan->rx_credits);
- l2cap_chan_le_send_credits(chan);
+ /* Update if remote had run out of credits, this should only happens
+ * if the remote is not using the entire MPS.
+ */
+ if (!chan->rx_credits)
+ l2cap_chan_le_send_credits(chan);
err = 0;
}
if (skb->len == sdu_len)
- return chan->ops->recv(chan, skb);
+ return l2cap_le_recv(chan, skb);
chan->sdu = skb;
chan->sdu_len = sdu_len;
skb = NULL;
if (chan->sdu->len == chan->sdu_len) {
- err = chan->ops->recv(chan, chan->sdu);
+ err = l2cap_le_recv(chan, chan->sdu);
if (!err) {
chan->sdu = NULL;
chan->sdu_last_frag = NULL;
l2cap_debugfs = debugfs_create_file("l2cap", 0444, bt_debugfs,
NULL, &l2cap_debugfs_fops);
- debugfs_create_u16("l2cap_le_max_credits", 0644, bt_debugfs,
- &le_max_credits);
-
return 0;
}