remote_tx_win is intended to be set on receipt of an L2CAP
configuration request.  The value is used to determine the size of the
transmit window on the remote side of an ERTM connection, so L2CAP
can stop sending frames when that remote window is full.

An incorrect remote_tx_win value will cause the stack to not fully
utilize the tx window (performance impact), or to overfill the remote
tx window (causing dropped frames or a disconnect).

This patch removes an extra setting of remote_tx_win when a
configuration response is received.  The transmit window has a
different meaning in a response - it is an informational value
less than or equal to the local tx_win.
Signed-off-by: NMat Martineau <mathewm@codeaurora.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Incoming configuration values must be converted to native CPU order
before use.  This fixes a bug where a little-endian MPS value is
compared to a native CPU value.  On big-endian processors, this
can cause ERTM and streaming mode segmentation to produce PDUs
that are larger than the remote stack is expecting, or that would
produce fragmented skbs that the current FCS code cannot handle.
Signed-off-by: NMat Martineau <mathewm@codeaurora.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Check result code of L2CAP information response. Otherwise
it would read invalid feature mask and access invalid memory.
Signed-off-by: NVille Tervo <ville.tervo@nokia.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

If the remote side doesn't support Enhanced Retransmission Mode neither
Streaming Mode, we shall not send the RFC option.

Some devices that only supports Basic Mode do not understanding the RFC
option. This patch fixes the regression found with these devices.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

rfcomm_cleanup_ttys() is also called from rfcomm_init(), so it can't
have __exit.
Reported-by: NMat Martineau <mathewm@codeaurora.org>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The bdaddr in the list root is completely unused and just
taking up space.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Tested-by: NJohan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Those annotation save memory and space on the binary. __init code is
discarded just after execute and __exit code is discarded if the module
is built into the kernel image or unload of modules is not allowed.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Testing first we avoid enter the loop when count = 0.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Certain headsets such as the Motorola H350 will reject SCO and eSCO
connection requests while the ACL is transitioning from sniff mode
to active mode. Add synchronization so that SCO and eSCO connection
requests will wait until the ACL has fully transitioned to active mode.

< HCI Command: Exit Sniff Mode (0x02|0x0004) plen 2
    handle 12
> HCI Event: Command Status (0x0f) plen 4
    Exit Sniff Mode (0x02|0x0004) status 0x00 ncmd 1
< HCI Command:  Setup Synchronous Connection (0x01|0x0028) plen 17
    handle 12 voice setting 0x0040
> HCI Event: Command Status (0x0f) plen 4
    Setup Synchronous Connection (0x01|0x0028) status 0x00 ncmd 1
> HCI Event: Number of Completed Packets (0x13) plen 5
    handle 12 packets 1
> HCI Event: Mode Change (0x14) plen 6
    status 0x00 handle 12 mode 0x00 interval 0
    Mode: Active
> HCI Event: Synchronous Connect Complete (0x2c) plen 17
    status 0x10 handle 14 bdaddr 00:1A:0E:50:28:A4 type SCO
    Error: Connection Accept Timeout Exceeded
Signed-off-by: NRon Shaffer <rshaffer@codeaurora.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Change the enable_ertm param to disable_ertm and default value to 0. That
means that L2CAP Extended features are enabled by default now.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

memmory -> memory
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Implemented frame reassembly implementation for reassembling fragments
received from stream.
Signed-off-by: NSuraj Sumangala <suraj@atheros.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Modified packet based reassembly function hci_recv_fragment() to use
hci_reassembly()
Signed-off-by: NSuraj Sumangala <suraj@atheros.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Implements feature to reassemble received HCI frames from any input stream
Signed-off-by: NSuraj Sumangala <suraj@atheros.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Additional reassembly buffer to keep track of stream reasembly
Signed-off-by: NSuraj Sumangala <suraj@atheros.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

We did some changes on the L2CAP configuration process and its behaviour
is bit different now. That justifies a updated on the L2CAP version.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Copyright for the time I worked on L2CAP during the Google Summer of Code
program.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Purely a cosmetic change, it doesn't change the code flow.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Probably a typo error. We were using the wrong struct to get size.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The extended L2CAP features requires that one should initiate a
ConfigReq after send the ConnectionRsp. This patch changes the behaviour
of the configuration process of our stack.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

L2CAP only deals with ACL links. EINVAL should be returned otherwise.
Signed-off-by: NJoão Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Signed-off-by: NJoão Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Signed-off-by: NJoão Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

When the socket is in a bad state EBADFD is more appropriate then EINVAL.
Signed-off-by: NJoão Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

When we try to send a message bigger than the outgoing MTU value
EMSGSIZE (message too long) should be returned.
Signed-off-by: NJoão Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

It doesn't make sense to have a return value since we always set it
to 0.
Signed-off-by: NJoão Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Return a proper error value if socket is already connected.
Signed-off-by: NJoão Paulo Rechi Vita <jprvita@profusion.mobi>
Acked-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Now we also check if can push skb userspace just after receive a new
skb instead of only wait the l2cap_busy_work wake up from time to time
to check the local busy condition.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

backlog queue is the canonical mechanism to avoid race conditions due
interrupts in bottom half context. After the socket lock is released the
net core take care of push all skb in its backlog queue.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Using a lock to deal with the ERTM race condition - interruption with
new data from the hci layer - is wrong. We should use the native skb
backlog queue.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

If such event happens we shall reply with a Command Reject, because we are
not expecting any configure request.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

When mode is mandatory we shall not send connect request and report this
to the userspace as well.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Since now we have checks for the supported mode before on
l2cap_info_rsp we can remove the check for it here.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

If our mode is Basic Mode we have to refuse any ConfigRsp that proposes
a different mode.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The Profile Tuning Suite requires that we send a RFC containing the
Basic Mode configuration when requesting Basic Mode.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

If we choose to use Basic Mode then we have to refuse the received mode
and propose Basic Mode again.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

If the device is a STATE 2 then it should disconnect the channel if the
remote device propose a mode different from its mandatory mode.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

If the socket type is SOCK_STREAM we set Enhanced Retransmisson Mode or
Streaming Mode as mandatory. That means that we will close the channel
if the other side doesn't support or request the the mandatory mode.
Basic mode can't be set as mandatory.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: NJoão Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

l2cap_send_sframe() already set the F-bit if we set L2CAP_CONN_SEND_FBIT
and unset L2CAP_CONN_SEND_FBIT after send the F-bit.
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Reviewed-by: NJoão Paulo Rechi Vita <jprvita@profusion.mobi>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>