Commit 177f8f2b authored by Johan Hedberg's avatar Johan Hedberg Committed by Marcel Holtmann

Bluetooth: Add LE L2CAP segmentation support for outgoing data

This patch adds segmentation support for outgoing data packets. Packets
are segmented based on the MTU and MPS values. The l2cap_chan struct
already contains many helpful variables from BR/EDR Enhanced L2CAP which
can be used for this.
Signed-off-by: default avatarJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
parent 837776f7
......@@ -607,6 +607,7 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err)
break;
case L2CAP_MODE_LE_FLOWCTL:
skb_queue_purge(&chan->tx_q);
break;
case L2CAP_MODE_ERTM:
......@@ -1194,12 +1195,24 @@ static void l2cap_move_done(struct l2cap_chan *chan)
}
}
static void l2cap_le_flowctl_start(struct l2cap_chan *chan)
{
chan->sdu = NULL;
chan->sdu_last_frag = NULL;
chan->sdu_len = 0;
skb_queue_head_init(&chan->tx_q);
}
static void l2cap_chan_ready(struct l2cap_chan *chan)
{
/* This clears all conf flags, including CONF_NOT_COMPLETE */
chan->conf_state = 0;
__clear_chan_timer(chan);
if (chan->mode == L2CAP_MODE_LE_FLOWCTL)
l2cap_le_flowctl_start(chan);
chan->state = BT_CONNECTED;
chan->ops->ready(chan);
......@@ -2521,6 +2534,89 @@ static int l2cap_segment_sdu(struct l2cap_chan *chan,
return 0;
}
static struct sk_buff *l2cap_create_le_flowctl_pdu(struct l2cap_chan *chan,
struct msghdr *msg,
size_t len, u16 sdulen)
{
struct l2cap_conn *conn = chan->conn;
struct sk_buff *skb;
int err, count, hlen;
struct l2cap_hdr *lh;
BT_DBG("chan %p len %zu", chan, len);
if (!conn)
return ERR_PTR(-ENOTCONN);
hlen = L2CAP_HDR_SIZE;
if (sdulen)
hlen += L2CAP_SDULEN_SIZE;
count = min_t(unsigned int, (conn->mtu - hlen), len);
skb = chan->ops->alloc_skb(chan, count + hlen,
msg->msg_flags & MSG_DONTWAIT);
if (IS_ERR(skb))
return skb;
/* Create L2CAP header */
lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
lh->cid = cpu_to_le16(chan->dcid);
lh->len = cpu_to_le16(len + (hlen - L2CAP_HDR_SIZE));
if (sdulen)
put_unaligned_le16(sdulen, skb_put(skb, L2CAP_SDULEN_SIZE));
err = l2cap_skbuff_fromiovec(chan, msg, len, count, skb);
if (unlikely(err < 0)) {
kfree_skb(skb);
return ERR_PTR(err);
}
return skb;
}
static int l2cap_segment_le_sdu(struct l2cap_chan *chan,
struct sk_buff_head *seg_queue,
struct msghdr *msg, size_t len)
{
struct sk_buff *skb;
size_t pdu_len;
u16 sdu_len;
BT_DBG("chan %p, msg %p, len %zu", chan, msg, len);
pdu_len = chan->conn->mtu - L2CAP_HDR_SIZE;
pdu_len = min_t(size_t, pdu_len, chan->remote_mps);
sdu_len = len;
pdu_len -= L2CAP_SDULEN_SIZE;
while (len > 0) {
if (len <= pdu_len)
pdu_len = len;
skb = l2cap_create_le_flowctl_pdu(chan, msg, pdu_len, sdu_len);
if (IS_ERR(skb)) {
__skb_queue_purge(seg_queue);
return PTR_ERR(skb);
}
__skb_queue_tail(seg_queue, skb);
len -= pdu_len;
if (sdu_len) {
sdu_len = 0;
pdu_len += L2CAP_SDULEN_SIZE;
}
}
return 0;
}
int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len,
u32 priority)
{
......@@ -2543,10 +2639,39 @@ int l2cap_chan_send(struct l2cap_chan *chan, struct msghdr *msg, size_t len,
switch (chan->mode) {
case L2CAP_MODE_LE_FLOWCTL:
/* Check outgoing MTU */
if (len > chan->omtu)
return -EMSGSIZE;
if (!chan->tx_credits)
return -EAGAIN;
/* fall through */
__skb_queue_head_init(&seg_queue);
err = l2cap_segment_le_sdu(chan, &seg_queue, msg, len);
if (chan->state != BT_CONNECTED) {
__skb_queue_purge(&seg_queue);
err = -ENOTCONN;
}
if (err)
return err;
skb_queue_splice_tail_init(&seg_queue, &chan->tx_q);
while (chan->tx_credits && !skb_queue_empty(&chan->tx_q)) {
l2cap_do_send(chan, skb_dequeue(&chan->tx_q));
chan->tx_credits--;
}
if (!chan->tx_credits)
chan->ops->suspend(chan);
err = len;
break;
case L2CAP_MODE_BASIC:
/* Check outgoing MTU */
if (len > chan->omtu)
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment