Bluetooth: RFCOMM: Use MTU auto tune logic

This reuse the L2CAP MTU auto logic to select the MTU used for RFCOMM
channels, this should increase the maximum from 1013 to 1021 when 3-DH5
is supported.

Since it does not set an L2CAP MTU we no longer need a debugfs so that
is removed.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/include/net/bluetooth/rfcomm.h b/include/net/bluetooth/rfcomm.h
index da4acef..8d65d2a 100644 (file)
--- a/include/net/bluetooth/rfcomm.h
+++ b/include/net/bluetooth/rfcomm.h
@@ -34,7 +34,6 @@
 #define RFCOMM_DEFAULT_MTU     127
 #define RFCOMM_DEFAULT_CREDITS 7
 
-#define RFCOMM_MAX_L2CAP_MTU   1013
 #define RFCOMM_MAX_CREDITS     40
 
 #define RFCOMM_SKB_HEAD_RESERVE        8

diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index dcecce0..2e20af3 100644 (file)
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -40,7 +40,6 @@
 static bool disable_cfc;
 static bool l2cap_ertm;
 static int channel_mtu = -1;
-static unsigned int l2cap_mtu = RFCOMM_MAX_L2CAP_MTU;
 
 static struct task_struct *rfcomm_thread;
 
@@ -749,7 +748,8 @@ static struct rfcomm_session *rfcomm_session_create(bdaddr_t *src,
        /* Set L2CAP options */
        sk = sock->sk;
        lock_sock(sk);
-       l2cap_pi(sk)->chan->imtu = l2cap_mtu;
+       /* Set MTU to 0 so L2CAP can auto select the MTU */
+       l2cap_pi(sk)->chan->imtu = 0;
        l2cap_pi(sk)->chan->sec_level = sec_level;
        if (l2cap_ertm)
                l2cap_pi(sk)->chan->mode = L2CAP_MODE_ERTM;
@@ -2036,7 +2036,8 @@ static int rfcomm_add_listener(bdaddr_t *ba)
        /* Set L2CAP options */
        sk = sock->sk;
        lock_sock(sk);
-       l2cap_pi(sk)->chan->imtu = l2cap_mtu;
+       /* Set MTU to 0 so L2CAP can auto select the MTU */
+       l2cap_pi(sk)->chan->imtu = 0;
        release_sock(sk);
 
        /* Start listening on the socket */
@@ -2234,9 +2235,6 @@ MODULE_PARM_DESC(disable_cfc, "Disable credit based flow control");
 module_param(channel_mtu, int, 0644);
 MODULE_PARM_DESC(channel_mtu, "Default MTU for the RFCOMM channel");
 
-module_param(l2cap_mtu, uint, 0644);
-MODULE_PARM_DESC(l2cap_mtu, "Default MTU for the L2CAP connection");
-
 module_param(l2cap_ertm, bool, 0644);
 MODULE_PARM_DESC(l2cap_ertm, "Use L2CAP ERTM mode for connection");