[PATCH v2 1/2] Bluetooth: Rename L2CAP_CHAN_CONN_FIX_A2MP to L2CAP_CHAN_FIXED

[PATCH v2 1/2] Bluetooth: Rename L2CAP_CHAN_CONN_FIX_A2MP to L2CAP_CHAN_FIXED

[johan.hedberg]

From: Johan Hedberg <johan.hedberg@intel.com>

There's no reason why A2MP should need or deserve its on channel type.
Instead we should be able to group all fixed CID users under a single
channel type and reuse as much code as possible for them. Where CID
specific exceptions are needed the chan-scid value can be used.

This patch renames the current A2MP channel type to a generic one and
thereby paves the way to allow converting ATT and SMP (and any future
fixed channel protocols) to use the new channel type.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
---
 include/net/bluetooth/l2cap.h |  2 +-
 net/bluetooth/a2mp.c          |  8 ++++++--
 net/bluetooth/l2cap_core.c    | 15 ++++++---------
 3 files changed, 13 insertions(+), 12 deletions(-)

diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 85cf40acc47e..ae482f41594a 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -651,7 +651,7 @@ struct l2cap_user {
 #define L2CAP_CHAN_RAW			1
 #define L2CAP_CHAN_CONN_LESS		2
 #define L2CAP_CHAN_CONN_ORIENTED	3
-#define L2CAP_CHAN_CONN_FIX_A2MP	4
+#define L2CAP_CHAN_FIXED		4
 
 /* ----- L2CAP socket info ----- */
 #define l2cap_pi(sk) ((struct l2cap_pinfo *) sk)
diff --git a/net/bluetooth/a2mp.c b/net/bluetooth/a2mp.c
index efcd108822c4..f986b9968bdb 100644
--- a/net/bluetooth/a2mp.c
+++ b/net/bluetooth/a2mp.c
@@ -235,7 +235,7 @@ static int a2mp_discover_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
 			BT_DBG("chan %p state %s", chan,
 			       state_to_string(chan->state));
 
-			if (chan->chan_type == L2CAP_CHAN_CONN_FIX_A2MP)
+			if (chan->scid == L2CAP_CID_A2MP)
 				continue;
 
 			l2cap_chan_lock(chan);
@@ -726,7 +726,11 @@ static struct l2cap_chan *a2mp_chan_open(struct l2cap_conn *conn, bool locked)
 
 	BT_DBG("chan %p", chan);
 
-	chan->chan_type = L2CAP_CHAN_CONN_FIX_A2MP;
+	chan->chan_type = L2CAP_CHAN_FIXED;
+	chan->scid = L2CAP_CID_A2MP;
+	chan->dcid = L2CAP_CID_A2MP;
+	chan->omtu = L2CAP_A2MP_DEFAULT_MTU;
+	chan->imtu = L2CAP_A2MP_DEFAULT_MTU;
 	chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
 
 	chan->ops = &a2mp_chan_ops;
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 138394ad3e51..cd28057d2903 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -519,11 +519,8 @@ void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 		chan->omtu = L2CAP_DEFAULT_MTU;
 		break;
 
-	case L2CAP_CHAN_CONN_FIX_A2MP:
-		chan->scid = L2CAP_CID_A2MP;
-		chan->dcid = L2CAP_CID_A2MP;
-		chan->omtu = L2CAP_A2MP_DEFAULT_MTU;
-		chan->imtu = L2CAP_A2MP_DEFAULT_MTU;
+	case L2CAP_CHAN_FIXED:
+		/* Caller will set CID and CID specific MTU values */
 		break;
 
 	default:
@@ -571,7 +568,7 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err)
 
 		chan->conn = NULL;
 
-		if (chan->chan_type != L2CAP_CHAN_CONN_FIX_A2MP)
+		if (chan->scid != L2CAP_CID_A2MP)
 			hci_conn_drop(conn->hcon);
 
 		if (mgr && mgr->bredr_chan == chan)
@@ -1310,7 +1307,7 @@ static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err)
 		__clear_ack_timer(chan);
 	}
 
-	if (chan->chan_type == L2CAP_CHAN_CONN_FIX_A2MP) {
+	if (chan->scid == L2CAP_CID_A2MP) {
 		l2cap_state_change(chan, BT_DISCONN);
 		return;
 	}
@@ -1508,7 +1505,7 @@ static void l2cap_conn_ready(struct l2cap_conn *conn)
 
 		l2cap_chan_lock(chan);
 
-		if (chan->chan_type == L2CAP_CHAN_CONN_FIX_A2MP) {
+		if (chan->scid == L2CAP_CID_A2MP) {
 			l2cap_chan_unlock(chan);
 			continue;
 		}
@@ -7245,7 +7242,7 @@ int l2cap_security_cfm(struct hci_conn *hcon, u8 status, u8 encrypt)
 		BT_DBG("chan %p scid 0x%4.4x state %s", chan, chan->scid,
 		       state_to_string(chan->state));
 
-		if (chan->chan_type == L2CAP_CHAN_CONN_FIX_A2MP) {
+		if (chan->scid == L2CAP_CID_A2MP) {
 			l2cap_chan_unlock(chan);
 			continue;
 		}
-- 
1.8.5.3

[PATCH v2 2/2] Bluetooth: Switch ATT channels to use L2CAP_CHAN_FIXED

[johan.hedberg]

From: Johan Hedberg <johan.hedberg@intel.com>

ATT channels are not connection oriented so having them use
L2CAP_CHAN_CONN_ORIENTED is quite confusing. Instead, use the new
L2CAP_CHAN_FIXED type and ensure that the MTU and CID values get
properly set.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
---
 net/bluetooth/l2cap_core.c | 21 +++++++++------------
 net/bluetooth/l2cap_sock.c |  9 +++++++++
 2 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index cd28057d2903..e5c5c7427c41 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -498,18 +498,10 @@ void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan)
 
 	switch (chan->chan_type) {
 	case L2CAP_CHAN_CONN_ORIENTED:
-		if (conn->hcon->type == LE_LINK) {
-			if (chan->dcid == L2CAP_CID_ATT) {
-				chan->omtu = L2CAP_DEFAULT_MTU;
-				chan->scid = L2CAP_CID_ATT;
-			} else {
-				chan->scid = l2cap_alloc_cid(conn);
-			}
-		} else {
-			/* Alloc CID for connection-oriented socket */
-			chan->scid = l2cap_alloc_cid(conn);
+		/* Alloc CID for connection-oriented socket */
+		chan->scid = l2cap_alloc_cid(conn);
+		if (conn->hcon->type == ACL_LINK)
 			chan->omtu = L2CAP_DEFAULT_MTU;
-		}
 		break;
 
 	case L2CAP_CHAN_CONN_LESS:
@@ -7025,7 +7017,12 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
 		goto done;
 	}
 
-	if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !(psm || cid)) {
+	if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED && !psm) {
+		err = -EINVAL;
+		goto done;
+	}
+
+	if (chan->chan_type == L2CAP_CHAN_FIXED && !cid) {
 		err = -EINVAL;
 		goto done;
 	}
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 4aa6704f0b33..3f8e2a223474 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -101,6 +101,15 @@ static int l2cap_sock_bind(struct socket *sock, struct sockaddr *addr, int alen)
 	if (!bdaddr_type_is_valid(la.l2_bdaddr_type))
 		return -EINVAL;
 
+	if (la.l2_cid) {
+		/* When the socket gets created it defaults to
+		 * CHAN_CONN_ORIENTED, so we need to overwrite the
+		 * default here.
+		 */
+		chan->chan_type = L2CAP_CHAN_FIXED;
+		chan->omtu = L2CAP_DEFAULT_MTU;
+	}
+
 	if (bdaddr_type_is_le(la.l2_bdaddr_type)) {
 		if (!enable_lecoc && la.l2_psm)
 			return -EINVAL;
-- 
1.8.5.3

Re: [PATCH v2 2/2] Bluetooth: Switch ATT channels to use L2CAP_CHAN_FIXED

[Marcel Holtmann]

Hi Johan,

> ATT channels are not connection oriented so having them use
> L2CAP_CHAN_CONN_ORIENTED is quite confusing. Instead, use the new
> L2CAP_CHAN_FIXED type and ensure that the MTU and CID values get
> properly set.
> 
> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
> ---
> net/bluetooth/l2cap_core.c | 21 +++++++++------------
> net/bluetooth/l2cap_sock.c |  9 +++++++++
> 2 files changed, 18 insertions(+), 12 deletions(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel

Re: [PATCH v2 1/2] Bluetooth: Rename L2CAP_CHAN_CONN_FIX_A2MP to L2CAP_CHAN_FIXED

[Marcel Holtmann]

Hi Johan,

> There's no reason why A2MP should need or deserve its on channel type.
> Instead we should be able to group all fixed CID users under a single
> channel type and reuse as much code as possible for them. Where CID
> specific exceptions are needed the chan-scid value can be used.
> 
> This patch renames the current A2MP channel type to a generic one and
> thereby paves the way to allow converting ATT and SMP (and any future
> fixed channel protocols) to use the new channel type.
> 
> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
> ---
> include/net/bluetooth/l2cap.h |  2 +-
> net/bluetooth/a2mp.c          |  8 ++++++--
> net/bluetooth/l2cap_core.c    | 15 ++++++---------
> 3 files changed, 13 insertions(+), 12 deletions(-)

patch has been applied to bluetooth-next tree.

Regards

Marcel