[PATCH v5 0/3] Enable use of L2CAP_MODE_EXT_FLOWCTL

[PATCH v5 0/3] Enable use of L2CAP_MODE_EXT_FLOWCTL

[Luiz Augusto von Dentz]

From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

This enables use of BT_MODE_EXT_FLOWCTL with BT_MODE socketopt, in
addition to that add support for DEFER_SETUP to be used with client
sockets so they can be grouped and sent together.

BT_MODE is not compatible with L2CAP_OPTIONS so attempting to use them
both will cause an error to be returned to the applicatio.

This has been tested by introducing support for L2CAP_MODE_EXT_FLOWCTL
into l2cap-tester which now produces the following trace:

Enable ecred PDUs:
#echo 1 > /sys/module/bluetooth/parameters/enable_ecred

#sudo tools/l2cap-tester -p "L2CAP Ext-Flowctl"
L2CAP Ext-Flowctl Client - Success - init
  Read Index List callback
    Status: 0x00
  New hciemu instance created
  Index Added callback
    Index: 0x0000
  Read Info callback
    Status: 0x00
    Address: 00:AA:01:00:00:00
    Version: 0x09
    Manufacturer: 0x003f
    Supported settings: 0x0001be1b
    Current settings: 0x00000200
    Class: 0x000000
    Name:
    Short name:
L2CAP Ext-Flowctl Client - Success - setup
  Powering on controller
  Controller powered on
  Client set connectable status 0x00
L2CAP Ext-Flowctl Client - Success - setup complete
L2CAP Ext-Flowctl Client - Success - run
  Connect in progress
  Successfully connected
L2CAP Ext-Flowctl Client - Success - test passed
L2CAP Ext-Flowctl Client - Success - teardown
  Index Removed callback
    Index: 0x0000
L2CAP Ext-Flowctl Client - Success - teardown complete
L2CAP Ext-Flowctl Client - Success - done

L2CAP Ext-Flowctl Client, Direct Advertising - Success - init
  Read Index List callback
    Status: 0x00
  New hciemu instance created
  Index Added callback
    Index: 0x0000
  Read Info callback
    Status: 0x00
    Address: 00:AA:01:00:00:00
    Version: 0x09
    Manufacturer: 0x003f
    Supported settings: 0x0001be1b
    Current settings: 0x00000200
    Class: 0x000000
    Name:
    Short name:
L2CAP Ext-Flowctl Client, Direct Advertising - Success - setup
  Powering on controller
  Controller powered on
  Client set connectable status 0x00
L2CAP Ext-Flowctl Client, Direct Advertising - Success - setup complete
L2CAP Ext-Flowctl Client, Direct Advertising - Success - run
  Connect in progress
  Received advertising parameters HCI command
L2CAP Ext-Flowctl Client, Direct Advertising - Success - test passed
L2CAP Ext-Flowctl Client, Direct Advertising - Success - teardown
  Index Removed callback
    Index: 0x0000
L2CAP Ext-Flowctl Client, Direct Advertising - Success - teardown complete
L2CAP Ext-Flowctl Client, Direct Advertising - Success - done

L2CAP Ext-Flowctl Client SMP - Success - init
  Read Index List callback
    Status: 0x00
  New hciemu instance created
  Index Added callback
    Index: 0x0000
  Read Info callback
    Status: 0x00
    Address: 00:AA:01:00:00:00
    Version: 0x09
    Manufacturer: 0x003f
    Supported settings: 0x0001be1b
    Current settings: 0x00000200
    Class: 0x000000
    Name:
    Short name:
L2CAP Ext-Flowctl Client SMP - Success - setup
  Powering on controller
  Controller powered on
  Client set connectable status 0x00
L2CAP Ext-Flowctl Client SMP - Success - setup complete
L2CAP Ext-Flowctl Client SMP - Success - run
  Connect in progress
  Successfully connected
L2CAP Ext-Flowctl Client SMP - Success - test passed
L2CAP Ext-Flowctl Client SMP - Success - teardown
  Index Removed callback
    Index: 0x0000
L2CAP Ext-Flowctl Client SMP - Success - teardown complete
L2CAP Ext-Flowctl Client SMP - Success - done

L2CAP Ext-Flowctl Client - Command Reject - init
  Read Index List callback
    Status: 0x00
  New hciemu instance created
  Index Added callback
    Index: 0x0000
  Read Info callback
    Status: 0x00
    Address: 00:AA:01:00:00:00
    Version: 0x09
    Manufacturer: 0x003f
    Supported settings: 0x0001be1b
    Current settings: 0x00000200
    Class: 0x000000
    Name:
    Short name:
L2CAP Ext-Flowctl Client - Command Reject - setup
  Powering on controller
  Controller powered on
  Client set connectable status 0x00
L2CAP Ext-Flowctl Client - Command Reject - setup complete
L2CAP Ext-Flowctl Client - Command Reject - run
  Connect in progress
  New connection with handle 0x002a
  Connect failed: Connection refused (111)
L2CAP Ext-Flowctl Client - Command Reject - test passed
L2CAP Ext-Flowctl Client - Command Reject - teardown
  Index Removed callback
    Index: 0x0000
L2CAP Ext-Flowctl Client - Command Reject - teardown complete
L2CAP Ext-Flowctl Client - Command Reject - done

L2CAP Ext-Flowctl Client - Open two sockets - init
  Read Index List callback
    Status: 0x00
  New hciemu instance created
  Index Added callback
    Index: 0x0000
  Read Info callback
    Status: 0x00
    Address: 00:AA:01:00:00:00
    Version: 0x09
    Manufacturer: 0x003f
    Supported settings: 0x0001be1b
    Current settings: 0x00000200
    Class: 0x000000
    Name:
    Short name:
L2CAP Ext-Flowctl Client - Open two sockets - setup
  Powering on controller
  Controller powered on
L2CAP Ext-Flowctl Client - Open two sockets - setup complete
L2CAP Ext-Flowctl Client - Open two sockets - run
  Connect in progress, sk = 19 (deferred)
  HCI Command 0x200b length 7
  HCI Command 0x200c length 2
  Connect in progress, sk = 20
  Client set connectable status 0x00
  HCI Command 0x200c length 2
  HCI Command 0x200d length 25
  HCI Command 0x2016 length 2
  Successfully connected
  Successfully connected
L2CAP Ext-Flowctl Client - Open two sockets - test passed
L2CAP Ext-Flowctl Client - Open two sockets - teardown
  Index Removed callback
    Index: 0x0000
L2CAP Ext-Flowctl Client - Open two sockets - teardown complete
L2CAP Ext-Flowctl Client - Open two sockets - done

L2CAP Ext-Flowctl Client - Open two sockets close one - init
  Read Index List callback
    Status: 0x00
  New hciemu instance created
  Index Added callback
    Index: 0x0000
  Read Info callback
    Status: 0x00
    Address: 00:AA:01:00:00:00
    Version: 0x09
    Manufacturer: 0x003f
    Supported settings: 0x0001be1b
    Current settings: 0x00000200
    Class: 0x000000
    Name:
    Short name:
L2CAP Ext-Flowctl Client - Open two sockets close one - setup
  Powering on controller
  Controller powered on
L2CAP Ext-Flowctl Client - Open two sockets close one - setup complete
L2CAP Ext-Flowctl Client - Open two sockets close one - run
  Connect in progress, sk = 19 (deferred)
  HCI Command 0x200b length 7
  HCI Command 0x200c length 2
  Connect in progress, sk = 20
  Closing first socket! -1
  Client set connectable status 0x00
  HCI Command 0x200c length 2
  HCI Command 0x200d length 25
  HCI Command 0x2016 length 2
  Successfully connected
L2CAP Ext-Flowctl Client - Open two sockets close one - test passed
L2CAP Ext-Flowctl Client - Open two sockets close one - teardown
  Index Removed callback
    Index: 0x0000
L2CAP Ext-Flowctl Client - Open two sockets close one - teardown complete
L2CAP Ext-Flowctl Client - Open two sockets close one - done


Test Summary
------------
L2CAP Ext-Flowctl Client - Success                   Passed       0.068 seconds
L2CAP Ext-Flowctl Client, Direct Advertising - Success Passed       0.023 seconds
L2CAP Ext-Flowctl Client SMP - Success               Passed       0.027 seconds
L2CAP Ext-Flowctl Client - Command Reject            Passed       0.046 seconds
L2CAP Ext-Flowctl Client - Open two sockets          Passed       0.014 seconds
L2CAP Ext-Flowctl Client - Open two sockets close one Passed       0.066 seconds
Total: 6, Passed: 6 (100.0%), Failed: 0, Not Run: 0
Overall execution time: 0.247 seconds

Luiz Augusto von Dentz (3):
  Bluetooth: L2CAP: Add get_peer_pid callback
  Bluetooth: L2CAP: Use DEFER_SETUP to group ECRED connections
  Bluetooth: Add BT_MODE socket option

 include/net/bluetooth/bluetooth.h |  11 +++
 include/net/bluetooth/l2cap.h     |   5 ++
 net/bluetooth/l2cap_core.c        | 136 +++++++++++++++++++++++++++---
 net/bluetooth/l2cap_sock.c        | 104 +++++++++++++++++++++++
 4 files changed, 246 insertions(+), 10 deletions(-)

-- 
2.21.1

[PATCH v5 1/3] Bluetooth: L2CAP: Add get_peer_pid callback

[Luiz Augusto von Dentz]

From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

This adds a callback to read the socket pid.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 include/net/bluetooth/l2cap.h | 1 +
 net/bluetooth/l2cap_sock.c    | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 537aaead259f..2d7d28474d34 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -660,6 +660,7 @@ struct l2cap_ops {
 	void			(*suspend) (struct l2cap_chan *chan);
 	void			(*set_shutdown) (struct l2cap_chan *chan);
 	long			(*get_sndtimeo) (struct l2cap_chan *chan);
+	struct pid		*(*get_peer_pid) (struct l2cap_chan *chan);
 	struct sk_buff		*(*alloc_skb) (struct l2cap_chan *chan,
 					       unsigned long hdr_len,
 					       unsigned long len, int nb);
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 40fb10b591bd..117ba20ea194 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -1504,6 +1504,13 @@ static long l2cap_sock_get_sndtimeo_cb(struct l2cap_chan *chan)
 	return sk->sk_sndtimeo;
 }
 
+static struct pid *l2cap_sock_get_peer_pid_cb(struct l2cap_chan *chan)
+{
+	struct sock *sk = chan->data;
+
+	return sk->sk_peer_pid;
+}
+
 static void l2cap_sock_suspend_cb(struct l2cap_chan *chan)
 {
 	struct sock *sk = chan->data;
@@ -1525,6 +1532,7 @@ static const struct l2cap_ops l2cap_chan_ops = {
 	.suspend		= l2cap_sock_suspend_cb,
 	.set_shutdown		= l2cap_sock_set_shutdown_cb,
 	.get_sndtimeo		= l2cap_sock_get_sndtimeo_cb,
+	.get_peer_pid		= l2cap_sock_get_peer_pid_cb,
 	.alloc_skb		= l2cap_sock_alloc_skb_cb,
 };
 
-- 
2.21.1

[PATCH v5 2/3] Bluetooth: L2CAP: Use DEFER_SETUP to group ECRED connections

[Luiz Augusto von Dentz]

From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

This uses the DEFER_SETUP flag to group channels with
L2CAP_CREDIT_BASED_CONNECTION_REQ.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 include/net/bluetooth/l2cap.h |   4 +
 net/bluetooth/l2cap_core.c    | 136 +++++++++++++++++++++++++++++++---
 2 files changed, 130 insertions(+), 10 deletions(-)

diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 2d7d28474d34..dada14d0622c 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -47,6 +47,7 @@
 #define L2CAP_DEFAULT_ACC_LAT		0xFFFFFFFF
 #define L2CAP_BREDR_MAX_PAYLOAD		1019    /* 3-DH5 packet */
 #define L2CAP_LE_MIN_MTU		23
+#define L2CAP_ECRED_CONN_SCID_MAX	5
 
 #define L2CAP_DISC_TIMEOUT		msecs_to_jiffies(100)
 #define L2CAP_DISC_REJ_TIMEOUT		msecs_to_jiffies(5000)
@@ -984,6 +985,9 @@ void l2cap_chan_set_defaults(struct l2cap_chan *chan);
 int l2cap_ertm_init(struct l2cap_chan *chan);
 void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan);
 void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan);
+typedef void (*l2cap_chan_func_t)(struct l2cap_chan *chan, void *data);
+void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
+		     void *data);
 void l2cap_chan_del(struct l2cap_chan *chan, int err);
 void l2cap_send_conn_req(struct l2cap_chan *chan);
 void l2cap_move_start(struct l2cap_chan *chan);
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 5e6e35ab44dd..9f699d09d973 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -678,6 +678,29 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err)
 }
 EXPORT_SYMBOL_GPL(l2cap_chan_del);
 
+static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
+			      void *data)
+{
+	struct l2cap_chan *chan;
+
+	list_for_each_entry(chan, &conn->chan_l, list) {
+		func(chan, data);
+	}
+}
+
+void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
+		     void *data)
+{
+	if (!conn)
+		return;
+
+	mutex_lock(&conn->chan_lock);
+	__l2cap_chan_list(conn, func, data);
+	mutex_unlock(&conn->chan_lock);
+}
+
+EXPORT_SYMBOL_GPL(l2cap_chan_list);
+
 static void l2cap_conn_update_id_addr(struct work_struct *work)
 {
 	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
@@ -1356,29 +1379,79 @@ static void l2cap_le_connect(struct l2cap_chan *chan)
 		       sizeof(req), &req);
 }
 
-static void l2cap_ecred_connect(struct l2cap_chan *chan)
-{
-	struct l2cap_conn *conn = chan->conn;
+struct l2cap_ecred_conn_data {
 	struct {
 		struct l2cap_ecred_conn_req req;
-		__le16 scid;
+		__le16 scid[5];
 	} __packed pdu;
+	struct l2cap_chan *chan;
+	struct pid *pid;
+	int count;
+};
+
+static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data)
+{
+	struct l2cap_ecred_conn_data *conn = data;
+	struct pid *pid;
+
+	if (chan == conn->chan)
+		return;
+
+	if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags))
+		return;
+
+	pid = chan->ops->get_peer_pid(chan);
+
+	/* Only add deferred channels with the same PID/PSM */
+	if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident ||
+	    chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
+		return;
+
+	if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
+		return;
+
+	l2cap_ecred_init(chan, 0);
+
+	/* Set the same ident so we can match on the rsp */
+	chan->ident = conn->chan->ident;
+
+	/* Include all channels deferred */
+	conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid);
+
+	conn->count++;
+}
+
+static void l2cap_ecred_connect(struct l2cap_chan *chan)
+{
+	struct l2cap_conn *conn = chan->conn;
+	struct l2cap_ecred_conn_data data;
+
+	if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
+		return;
 
 	if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
 		return;
 
 	l2cap_ecred_init(chan, 0);
 
-	pdu.req.psm     = chan->psm;
-	pdu.req.mtu     = cpu_to_le16(chan->imtu);
-	pdu.req.mps     = cpu_to_le16(chan->mps);
-	pdu.req.credits = cpu_to_le16(chan->rx_credits);
-	pdu.scid        = cpu_to_le16(chan->scid);
+	data.pdu.req.psm     = chan->psm;
+	data.pdu.req.mtu     = cpu_to_le16(chan->imtu);
+	data.pdu.req.mps     = cpu_to_le16(chan->mps);
+	data.pdu.req.credits = cpu_to_le16(chan->rx_credits);
+	data.pdu.scid[0]     = cpu_to_le16(chan->scid);
 
 	chan->ident = l2cap_get_ident(conn);
+	data.pid = chan->ops->get_peer_pid(chan);
+
+	data.count = 1;
+	data.chan = chan;
+	data.pid = chan->ops->get_peer_pid(chan);
+
+	__l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data);
 
 	l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ,
-		       sizeof(pdu), &pdu);
+		       sizeof(data.pdu.req) + data.count * sizeof(__le16),
+		       &data.pdu);
 }
 
 static void l2cap_le_start(struct l2cap_chan *chan)
@@ -7694,6 +7767,33 @@ static bool is_valid_psm(u16 psm, u8 dst_type) {
 	return ((psm & 0x0101) == 0x0001);
 }
 
+struct l2cap_chan_data {
+	struct l2cap_chan *chan;
+	struct pid *pid;
+	int count;
+};
+
+static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data)
+{
+	struct l2cap_chan_data *d = data;
+	struct pid *pid;
+
+	if (chan == d->chan)
+		return;
+
+	if (!test_bit(FLAG_DEFER_SETUP, &chan->flags))
+		return;
+
+	pid = chan->ops->get_peer_pid(chan);
+
+	/* Only count deferred channels with the same PID/PSM */
+	if (d->pid != pid || chan->psm != d->chan->psm || chan->ident ||
+	    chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
+		return;
+
+	d->count++;
+}
+
 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
 		       bdaddr_t *dst, u8 dst_type)
 {
@@ -7813,6 +7913,22 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
 		goto done;
 	}
 
+	if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
+		struct l2cap_chan_data data;
+
+		data.chan = chan;
+		data.pid = chan->ops->get_peer_pid(chan);
+		data.count = 0;
+
+		l2cap_chan_list(conn, l2cap_chan_by_pid, &data);
+		/* Check if there isn't too many channels being connected */
+		if (!(data.count < L2CAP_ECRED_CONN_SCID_MAX - 1)) {
+			hci_conn_drop(hcon);
+			err = -EPROTO;
+			goto done;
+		}
+	}
+
 	mutex_lock(&conn->chan_lock);
 	l2cap_chan_lock(chan);
 
-- 
2.21.1

[PATCH v5 3/3] Bluetooth: Add BT_MODE socket option

[Luiz Augusto von Dentz]

From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

This adds BT_MODE socket option which can be used to set L2CAP modes,
including modes only supported over LE which were not supported using
the L2CAP_OPTIONS.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 include/net/bluetooth/bluetooth.h |   8 ++
 include/net/bluetooth/l2cap.h     |   6 ++
 net/bluetooth/l2cap_sock.c        | 124 ++++++++++++++++++++++++++++++
 3 files changed, 138 insertions(+)

diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
index 1576353a2773..3fa7b1e3c5d9 100644
--- a/include/net/bluetooth/bluetooth.h
+++ b/include/net/bluetooth/bluetooth.h
@@ -139,6 +139,14 @@ struct bt_voice {
 #define BT_PHY_LE_CODED_TX	0x00002000
 #define BT_PHY_LE_CODED_RX	0x00004000
 
+#define BT_MODE			15
+
+#define BT_MODE_BASIC		0x00
+#define BT_MODE_ERTM		0x01
+#define BT_MODE_STREAMING	0x02
+#define BT_MODE_LE_FLOWCTL	0x03
+#define BT_MODE_EXT_FLOWCTL	0x04
+
 __printf(1, 2)
 void bt_info(const char *fmt, ...);
 __printf(1, 2)
diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index dada14d0622c..56f727ba23bd 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -720,9 +720,15 @@ struct l2cap_user {
 /* ----- L2CAP socket info ----- */
 #define l2cap_pi(sk) ((struct l2cap_pinfo *) sk)
 
+#define L2CAP_PI_OPTION_UNSET		0x00
+#define L2CAP_PI_OPTION_LEGACY		0x01
+#define L2CAP_PI_OPTION_BT_MODE		0x02
+
 struct l2cap_pinfo {
 	struct bt_sock		bt;
 	struct l2cap_chan	*chan;
+	u8			option;
+	u8			bt_mode;
 	struct sk_buff		*rx_busy_skb;
 };
 
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 117ba20ea194..0a57101fe273 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -424,6 +424,14 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname,
 			break;
 		}
 
+		/* Check if BT_MODE was used which is not compatible with
+		 * L2CAP_OPTIONS.
+		 */
+		if (l2cap_pi(sk)->option == L2CAP_PI_OPTION_BT_MODE) {
+			err = -EINVAL;
+			break;
+		}
+
 		memset(&opts, 0, sizeof(opts));
 		opts.imtu     = chan->imtu;
 		opts.omtu     = chan->omtu;
@@ -624,6 +632,29 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
 			err = -EFAULT;
 		break;
 
+	case BT_MODE:
+		if (!enable_ecred) {
+			err = -ENOPROTOOPT;
+			break;
+		}
+
+		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
+			err = -EINVAL;
+			break;
+		}
+
+		/* Check if L2CAP_OPTIONS was used which is not compatible with
+		 * BT_MODE.
+		 */
+		if (l2cap_pi(sk)->option == L2CAP_PI_OPTION_LEGACY) {
+			err = -EINVAL;
+			break;
+		}
+
+		if (put_user(l2cap_pi(sk)->bt_mode, (u8 __user *) optval))
+			err = -EFAULT;
+		break;
+
 	default:
 		err = -ENOPROTOOPT;
 		break;
@@ -674,6 +705,14 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname,
 			break;
 		}
 
+		/* Check if BT_MODE was used which is not compatible with
+		 * L2CAP_OPTIONS.
+		 */
+		if (l2cap_pi(sk)->option == L2CAP_PI_OPTION_BT_MODE) {
+			err = -EINVAL;
+			break;
+		}
+
 		opts.imtu     = chan->imtu;
 		opts.omtu     = chan->omtu;
 		opts.flush_to = chan->flush_to;
@@ -715,6 +754,8 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname,
 			break;
 		}
 
+		l2cap_pi(sk)->option = L2CAP_PI_OPTION_LEGACY;
+
 		BT_DBG("mode 0x%2.2x", chan->mode);
 
 		chan->imtu = opts.imtu;
@@ -763,6 +804,45 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname,
 	return err;
 }
 
+static int l2cap_set_mode(struct l2cap_chan *chan, u8 mode)
+{
+	switch (mode) {
+	case BT_MODE_BASIC:
+		if (bdaddr_type_is_le(chan->src_type))
+			return -EINVAL;
+		mode = L2CAP_MODE_BASIC;
+		clear_bit(CONF_STATE2_DEVICE, &chan->conf_state);
+		break;
+	case BT_MODE_ERTM:
+		if (!disable_ertm || bdaddr_type_is_le(chan->src_type))
+			return -EINVAL;
+		mode = L2CAP_MODE_ERTM;
+		break;
+	case BT_MODE_STREAMING:
+		if (!disable_ertm || bdaddr_type_is_le(chan->src_type))
+			return -EINVAL;
+		mode = L2CAP_MODE_STREAMING;
+		break;
+	case BT_MODE_LE_FLOWCTL:
+		if (!bdaddr_type_is_le(chan->src_type))
+			return -EINVAL;
+		mode = L2CAP_MODE_LE_FLOWCTL;
+		break;
+	case BT_MODE_EXT_FLOWCTL:
+		/* TODO: Add support for ECRED PDUs to BR/EDR */
+		if (!bdaddr_type_is_le(chan->src_type))
+			return -EINVAL;
+		mode = L2CAP_MODE_EXT_FLOWCTL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	chan->mode = mode;
+
+	return 0;
+}
+
 static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname,
 				 char __user *optval, unsigned int optlen)
 {
@@ -968,6 +1048,50 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname,
 
 		break;
 
+	case BT_MODE:
+		if (!enable_ecred) {
+			err = -ENOPROTOOPT;
+			break;
+		}
+
+		BT_DBG("sk->sk_state %u", sk->sk_state);
+
+		if (sk->sk_state != BT_BOUND) {
+			err = -EINVAL;
+			break;
+		}
+
+		if (chan->chan_type != L2CAP_CHAN_CONN_ORIENTED) {
+			err = -EINVAL;
+			break;
+		}
+
+		/* Check if L2CAP_OPTIONS was used which is not compatible with
+		 * BT_MODE.
+		 */
+		if (l2cap_pi(sk)->option == L2CAP_PI_OPTION_LEGACY) {
+			err = -EINVAL;
+			break;
+		}
+
+		if (get_user(opt, (u8 __user *) optval)) {
+			err = -EFAULT;
+			break;
+		}
+
+		BT_DBG("opt %u", opt);
+
+		err = l2cap_set_mode(chan, opt);
+		if (err)
+			break;
+
+		l2cap_pi(sk)->option = L2CAP_PI_OPTION_BT_MODE;
+		l2cap_pi(sk)->bt_mode = opt;
+
+		BT_DBG("mode 0x%2.2x", chan->mode);
+
+		break;
+
 	default:
 		err = -ENOPROTOOPT;
 		break;
-- 
2.21.1

Re: [PATCH v5 3/3] Bluetooth: Add BT_MODE socket option

[Marcel Holtmann]

Hi Luiz,

> This adds BT_MODE socket option which can be used to set L2CAP modes,
> including modes only supported over LE which were not supported using
> the L2CAP_OPTIONS.
> 
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> ---
> include/net/bluetooth/bluetooth.h |   8 ++
> include/net/bluetooth/l2cap.h     |   6 ++
> net/bluetooth/l2cap_sock.c        | 124 ++++++++++++++++++++++++++++++
> 3 files changed, 138 insertions(+)
> 
> diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
> index 1576353a2773..3fa7b1e3c5d9 100644
> --- a/include/net/bluetooth/bluetooth.h
> +++ b/include/net/bluetooth/bluetooth.h
> @@ -139,6 +139,14 @@ struct bt_voice {
> #define BT_PHY_LE_CODED_TX	0x00002000
> #define BT_PHY_LE_CODED_RX	0x00004000
> 
> +#define BT_MODE			15
> +
> +#define BT_MODE_BASIC		0x00
> +#define BT_MODE_ERTM		0x01
> +#define BT_MODE_STREAMING	0x02
> +#define BT_MODE_LE_FLOWCTL	0x03
> +#define BT_MODE_EXT_FLOWCTL	0x04
> +
> __printf(1, 2)
> void bt_info(const char *fmt, ...);
> __printf(1, 2)
> diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
> index dada14d0622c..56f727ba23bd 100644
> --- a/include/net/bluetooth/l2cap.h
> +++ b/include/net/bluetooth/l2cap.h
> @@ -720,9 +720,15 @@ struct l2cap_user {
> /* ----- L2CAP socket info ----- */
> #define l2cap_pi(sk) ((struct l2cap_pinfo *) sk)
> 
> +#define L2CAP_PI_OPTION_UNSET		0x00
> +#define L2CAP_PI_OPTION_LEGACY		0x01
> +#define L2CAP_PI_OPTION_BT_MODE		0x02
> +
> struct l2cap_pinfo {
> 	struct bt_sock		bt;
> 	struct l2cap_chan	*chan;
> +	u8			option;
> +	u8			bt_mode;
> 	struct sk_buff		*rx_busy_skb;
> };

why do you want to store bt_mode here. Whatever we have in l2cap_chan should be plenty.

I also looked at l2cap_sock_setsockopt_old and if you use L2CAP_OPTIONS and want to read BT_MODE, then everything should be fine. Same as setting BT_MODE (except EXT_FLOWCTL) and then reading L2CAP_OPTIONS is fine as well. We can all translate this properly and with have EINVAL return errors for not supported / disabled modes.

So the only time L2CAP_OPTIONS read should fail is if you use BT_MODE with EXT_FLOWCTL as mode. So you can just check the mode set in l2cap_chan. And we start using our new mode definition there and then convert it for L2CAP_OPTIONS.

Regards

Marcel

Re: [PATCH v5 2/3] Bluetooth: L2CAP: Use DEFER_SETUP to group ECRED connections

[Marcel Holtmann]

Hi Luiz,

> This uses the DEFER_SETUP flag to group channels with
> L2CAP_CREDIT_BASED_CONNECTION_REQ.
> 
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> ---
> include/net/bluetooth/l2cap.h |   4 +
> net/bluetooth/l2cap_core.c    | 136 +++++++++++++++++++++++++++++++---
> 2 files changed, 130 insertions(+), 10 deletions(-)
> 
> diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
> index 2d7d28474d34..dada14d0622c 100644
> --- a/include/net/bluetooth/l2cap.h
> +++ b/include/net/bluetooth/l2cap.h
> @@ -47,6 +47,7 @@
> #define L2CAP_DEFAULT_ACC_LAT		0xFFFFFFFF
> #define L2CAP_BREDR_MAX_PAYLOAD		1019    /* 3-DH5 packet */
> #define L2CAP_LE_MIN_MTU		23
> +#define L2CAP_ECRED_CONN_SCID_MAX	5
> 
> #define L2CAP_DISC_TIMEOUT		msecs_to_jiffies(100)
> #define L2CAP_DISC_REJ_TIMEOUT		msecs_to_jiffies(5000)
> @@ -984,6 +985,9 @@ void l2cap_chan_set_defaults(struct l2cap_chan *chan);
> int l2cap_ertm_init(struct l2cap_chan *chan);
> void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan);
> void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan);
> +typedef void (*l2cap_chan_func_t)(struct l2cap_chan *chan, void *data);
> +void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
> +		     void *data);
> void l2cap_chan_del(struct l2cap_chan *chan, int err);
> void l2cap_send_conn_req(struct l2cap_chan *chan);
> void l2cap_move_start(struct l2cap_chan *chan);
> diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
> index 5e6e35ab44dd..9f699d09d973 100644
> --- a/net/bluetooth/l2cap_core.c
> +++ b/net/bluetooth/l2cap_core.c
> @@ -678,6 +678,29 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err)
> }
> EXPORT_SYMBOL_GPL(l2cap_chan_del);
> 
> +static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
> +			      void *data)
> +{
> +	struct l2cap_chan *chan;
> +
> +	list_for_each_entry(chan, &conn->chan_l, list) {
> +		func(chan, data);
> +	}
> +}
> +
> +void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
> +		     void *data)
> +{
> +	if (!conn)
> +		return;
> +
> +	mutex_lock(&conn->chan_lock);
> +	__l2cap_chan_list(conn, func, data);
> +	mutex_unlock(&conn->chan_lock);
> +}
> +
> +EXPORT_SYMBOL_GPL(l2cap_chan_list);
> +
> static void l2cap_conn_update_id_addr(struct work_struct *work)
> {
> 	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
> @@ -1356,29 +1379,79 @@ static void l2cap_le_connect(struct l2cap_chan *chan)
> 		       sizeof(req), &req);
> }
> 
> -static void l2cap_ecred_connect(struct l2cap_chan *chan)
> -{
> -	struct l2cap_conn *conn = chan->conn;
> +struct l2cap_ecred_conn_data {
> 	struct {
> 		struct l2cap_ecred_conn_req req;
> -		__le16 scid;
> +		__le16 scid[5];
> 	} __packed pdu;
> +	struct l2cap_chan *chan;
> +	struct pid *pid;
> +	int count;
> +};
> +
> +static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data)
> +{
> +	struct l2cap_ecred_conn_data *conn = data;
> +	struct pid *pid;
> +
> +	if (chan == conn->chan)
> +		return;
> +
> +	if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags))
> +		return;
> +
> +	pid = chan->ops->get_peer_pid(chan);
> +
> +	/* Only add deferred channels with the same PID/PSM */
> +	if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident ||
> +	    chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
> +		return;
> +
> +	if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
> +		return;
> +
> +	l2cap_ecred_init(chan, 0);
> +
> +	/* Set the same ident so we can match on the rsp */
> +	chan->ident = conn->chan->ident;
> +
> +	/* Include all channels deferred */
> +	conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid);
> +
> +	conn->count++;
> +}
> +
> +static void l2cap_ecred_connect(struct l2cap_chan *chan)
> +{
> +	struct l2cap_conn *conn = chan->conn;
> +	struct l2cap_ecred_conn_data data;
> +
> +	if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
> +		return;
> 
> 	if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
> 		return;
> 
> 	l2cap_ecred_init(chan, 0);
> 
> -	pdu.req.psm     = chan->psm;
> -	pdu.req.mtu     = cpu_to_le16(chan->imtu);
> -	pdu.req.mps     = cpu_to_le16(chan->mps);
> -	pdu.req.credits = cpu_to_le16(chan->rx_credits);
> -	pdu.scid        = cpu_to_le16(chan->scid);
> +	data.pdu.req.psm     = chan->psm;
> +	data.pdu.req.mtu     = cpu_to_le16(chan->imtu);
> +	data.pdu.req.mps     = cpu_to_le16(chan->mps);
> +	data.pdu.req.credits = cpu_to_le16(chan->rx_credits);
> +	data.pdu.scid[0]     = cpu_to_le16(chan->scid);
> 
> 	chan->ident = l2cap_get_ident(conn);
> +	data.pid = chan->ops->get_peer_pid(chan);
> +
> +	data.count = 1;
> +	data.chan = chan;
> +	data.pid = chan->ops->get_peer_pid(chan);
> +
> +	__l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data);
> 
> 	l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ,
> -		       sizeof(pdu), &pdu);
> +		       sizeof(data.pdu.req) + data.count * sizeof(__le16),
> +		       &data.pdu);
> }
> 
> static void l2cap_le_start(struct l2cap_chan *chan)
> @@ -7694,6 +7767,33 @@ static bool is_valid_psm(u16 psm, u8 dst_type) {
> 	return ((psm & 0x0101) == 0x0001);
> }
> 
> +struct l2cap_chan_data {
> +	struct l2cap_chan *chan;
> +	struct pid *pid;
> +	int count;
> +};
> +
> +static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data)
> +{
> +	struct l2cap_chan_data *d = data;
> +	struct pid *pid;
> +
> +	if (chan == d->chan)
> +		return;
> +
> +	if (!test_bit(FLAG_DEFER_SETUP, &chan->flags))
> +		return;
> +
> +	pid = chan->ops->get_peer_pid(chan);
> +
> +	/* Only count deferred channels with the same PID/PSM */
> +	if (d->pid != pid || chan->psm != d->chan->psm || chan->ident ||
> +	    chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
> +		return;
> +
> +	d->count++;
> +}
> +
> int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
> 		       bdaddr_t *dst, u8 dst_type)
> {
> @@ -7813,6 +7913,22 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
> 		goto done;
> 	}
> 
> +	if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
> +		struct l2cap_chan_data data;
> +
> +		data.chan = chan;
> +		data.pid = chan->ops->get_peer_pid(chan);
> +		data.count = 0;
> +
> +		l2cap_chan_list(conn, l2cap_chan_by_pid, &data);

Put an empty line after this. It gives emphasis to the comment.

> +		/* Check if there isn't too many channels being connected */
> +		if (!(data.count < L2CAP_ECRED_CONN_SCID_MAX - 1)) {

If (data.count > L2CAP_ECRED_CONN_SCID_MIX) ???

> +			hci_conn_drop(hcon);
> +			err = -EPROTO;
> +			goto done;
> +		}
> +	}
> +
> 	mutex_lock(&conn->chan_lock);
> 	l2cap_chan_lock(chan);

Regards

Marcel

Re: [PATCH v5 1/3] Bluetooth: L2CAP: Add get_peer_pid callback

[Marcel Holtmann]

Hi Luiz,

> This adds a callback to read the socket pid.
> 
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> ---
> include/net/bluetooth/l2cap.h | 1 +
> net/bluetooth/l2cap_sock.c    | 8 ++++++++
> 2 files changed, 9 insertions(+)

patch has been applied to bluetooth-next tree.

Regards

Marcel

Re: [PATCH v5 3/3] Bluetooth: Add BT_MODE socket option

[Luiz Augusto von Dentz]

Hi Marcel,

On Tue, Mar 24, 2020 at 1:44 AM Marcel Holtmann <marcel@holtmann.org> wrote:
>
> Hi Luiz,
>
> > This adds BT_MODE socket option which can be used to set L2CAP modes,
> > including modes only supported over LE which were not supported using
> > the L2CAP_OPTIONS.
> >
> > Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> > ---
> > include/net/bluetooth/bluetooth.h |   8 ++
> > include/net/bluetooth/l2cap.h     |   6 ++
> > net/bluetooth/l2cap_sock.c        | 124 ++++++++++++++++++++++++++++++
> > 3 files changed, 138 insertions(+)
> >
> > diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
> > index 1576353a2773..3fa7b1e3c5d9 100644
> > --- a/include/net/bluetooth/bluetooth.h
> > +++ b/include/net/bluetooth/bluetooth.h
> > @@ -139,6 +139,14 @@ struct bt_voice {
> > #define BT_PHY_LE_CODED_TX    0x00002000
> > #define BT_PHY_LE_CODED_RX    0x00004000
> >
> > +#define BT_MODE                      15
> > +
> > +#define BT_MODE_BASIC                0x00
> > +#define BT_MODE_ERTM         0x01
> > +#define BT_MODE_STREAMING    0x02
> > +#define BT_MODE_LE_FLOWCTL   0x03
> > +#define BT_MODE_EXT_FLOWCTL  0x04
> > +
> > __printf(1, 2)
> > void bt_info(const char *fmt, ...);
> > __printf(1, 2)
> > diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
> > index dada14d0622c..56f727ba23bd 100644
> > --- a/include/net/bluetooth/l2cap.h
> > +++ b/include/net/bluetooth/l2cap.h
> > @@ -720,9 +720,15 @@ struct l2cap_user {
> > /* ----- L2CAP socket info ----- */
> > #define l2cap_pi(sk) ((struct l2cap_pinfo *) sk)
> >
> > +#define L2CAP_PI_OPTION_UNSET                0x00
> > +#define L2CAP_PI_OPTION_LEGACY               0x01
> > +#define L2CAP_PI_OPTION_BT_MODE              0x02
> > +
> > struct l2cap_pinfo {
> >       struct bt_sock          bt;
> >       struct l2cap_chan       *chan;
> > +     u8                      option;
> > +     u8                      bt_mode;
> >       struct sk_buff          *rx_busy_skb;
> > };
>
> why do you want to store bt_mode here. Whatever we have in l2cap_chan should be plenty.

Ive thought it would be cleaner to mess with types that comes from the
spec itself so l2cap_chan would continue to use them.

> I also looked at l2cap_sock_setsockopt_old and if you use L2CAP_OPTIONS and want to read BT_MODE, then everything should be fine. Same as setting BT_MODE (except EXT_FLOWCTL) and then reading L2CAP_OPTIONS is fine as well. We can all translate this properly and with have EINVAL return errors for not supported / disabled modes.
>
> So the only time L2CAP_OPTIONS read should fail is if you use BT_MODE with EXT_FLOWCTL as mode. So you can just check the mode set in l2cap_chan. And we start using our new mode definition there and then convert it for L2CAP_OPTIONS.

Sure, I thought it would be more efficient to not have conversions
back and forth but Im fine either way.

> Regards
>
> Marcel
>


-- 
Luiz Augusto von Dentz

Re: [PATCH v5 3/3] Bluetooth: Add BT_MODE socket option

[Marcel Holtmann]

Hi Luiz,

>>> This adds BT_MODE socket option which can be used to set L2CAP modes,
>>> including modes only supported over LE which were not supported using
>>> the L2CAP_OPTIONS.
>>> 
>>> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
>>> ---
>>> include/net/bluetooth/bluetooth.h |   8 ++
>>> include/net/bluetooth/l2cap.h     |   6 ++
>>> net/bluetooth/l2cap_sock.c        | 124 ++++++++++++++++++++++++++++++
>>> 3 files changed, 138 insertions(+)
>>> 
>>> diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h
>>> index 1576353a2773..3fa7b1e3c5d9 100644
>>> --- a/include/net/bluetooth/bluetooth.h
>>> +++ b/include/net/bluetooth/bluetooth.h
>>> @@ -139,6 +139,14 @@ struct bt_voice {
>>> #define BT_PHY_LE_CODED_TX    0x00002000
>>> #define BT_PHY_LE_CODED_RX    0x00004000
>>> 
>>> +#define BT_MODE                      15
>>> +
>>> +#define BT_MODE_BASIC                0x00
>>> +#define BT_MODE_ERTM         0x01
>>> +#define BT_MODE_STREAMING    0x02
>>> +#define BT_MODE_LE_FLOWCTL   0x03
>>> +#define BT_MODE_EXT_FLOWCTL  0x04
>>> +
>>> __printf(1, 2)
>>> void bt_info(const char *fmt, ...);
>>> __printf(1, 2)
>>> diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
>>> index dada14d0622c..56f727ba23bd 100644
>>> --- a/include/net/bluetooth/l2cap.h
>>> +++ b/include/net/bluetooth/l2cap.h
>>> @@ -720,9 +720,15 @@ struct l2cap_user {
>>> /* ----- L2CAP socket info ----- */
>>> #define l2cap_pi(sk) ((struct l2cap_pinfo *) sk)
>>> 
>>> +#define L2CAP_PI_OPTION_UNSET                0x00
>>> +#define L2CAP_PI_OPTION_LEGACY               0x01
>>> +#define L2CAP_PI_OPTION_BT_MODE              0x02
>>> +
>>> struct l2cap_pinfo {
>>>      struct bt_sock          bt;
>>>      struct l2cap_chan       *chan;
>>> +     u8                      option;
>>> +     u8                      bt_mode;
>>>      struct sk_buff          *rx_busy_skb;
>>> };
>> 
>> why do you want to store bt_mode here. Whatever we have in l2cap_chan should be plenty.
> 
> Ive thought it would be cleaner to mess with types that comes from the
> spec itself so l2cap_chan would continue to use them.

Actually the LE_FLOWCTL and EXT_FLOWCTL are not spec values either. Frankly I don’t care which ones we store right now. I am fine keeping the spec one for now and just translate it to BT_MODE.

>> I also looked at l2cap_sock_setsockopt_old and if you use L2CAP_OPTIONS and want to read BT_MODE, then everything should be fine. Same as setting BT_MODE (except EXT_FLOWCTL) and then reading L2CAP_OPTIONS is fine as well. We can all translate this properly and with have EINVAL return errors for not supported / disabled modes.
>> 
>> So the only time L2CAP_OPTIONS read should fail is if you use BT_MODE with EXT_FLOWCTL as mode. So you can just check the mode set in l2cap_chan. And we start using our new mode definition there and then convert it for L2CAP_OPTIONS.
> 
> Sure, I thought it would be more efficient to not have conversions
> back and forth but Im fine either way.

In the end it makes the code simpler to just do the conversion. And once we add a kernel option to disable setsockopt_old, we have less code.

Regards

Marcel

Re: [PATCH v5 2/3] Bluetooth: L2CAP: Use DEFER_SETUP to group ECRED connections

[Luiz Augusto von Dentz]

Hi Marcel,

On Tue, Mar 24, 2020 at 1:47 AM Marcel Holtmann <marcel@holtmann.org> wrote:
>
> Hi Luiz,
>
> > This uses the DEFER_SETUP flag to group channels with
> > L2CAP_CREDIT_BASED_CONNECTION_REQ.
> >
> > Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> > ---
> > include/net/bluetooth/l2cap.h |   4 +
> > net/bluetooth/l2cap_core.c    | 136 +++++++++++++++++++++++++++++++---
> > 2 files changed, 130 insertions(+), 10 deletions(-)
> >
> > diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
> > index 2d7d28474d34..dada14d0622c 100644
> > --- a/include/net/bluetooth/l2cap.h
> > +++ b/include/net/bluetooth/l2cap.h
> > @@ -47,6 +47,7 @@
> > #define L2CAP_DEFAULT_ACC_LAT         0xFFFFFFFF
> > #define L2CAP_BREDR_MAX_PAYLOAD               1019    /* 3-DH5 packet */
> > #define L2CAP_LE_MIN_MTU              23
> > +#define L2CAP_ECRED_CONN_SCID_MAX    5
> >
> > #define L2CAP_DISC_TIMEOUT            msecs_to_jiffies(100)
> > #define L2CAP_DISC_REJ_TIMEOUT                msecs_to_jiffies(5000)
> > @@ -984,6 +985,9 @@ void l2cap_chan_set_defaults(struct l2cap_chan *chan);
> > int l2cap_ertm_init(struct l2cap_chan *chan);
> > void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan);
> > void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan);
> > +typedef void (*l2cap_chan_func_t)(struct l2cap_chan *chan, void *data);
> > +void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
> > +                  void *data);
> > void l2cap_chan_del(struct l2cap_chan *chan, int err);
> > void l2cap_send_conn_req(struct l2cap_chan *chan);
> > void l2cap_move_start(struct l2cap_chan *chan);
> > diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
> > index 5e6e35ab44dd..9f699d09d973 100644
> > --- a/net/bluetooth/l2cap_core.c
> > +++ b/net/bluetooth/l2cap_core.c
> > @@ -678,6 +678,29 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err)
> > }
> > EXPORT_SYMBOL_GPL(l2cap_chan_del);
> >
> > +static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
> > +                           void *data)
> > +{
> > +     struct l2cap_chan *chan;
> > +
> > +     list_for_each_entry(chan, &conn->chan_l, list) {
> > +             func(chan, data);
> > +     }
> > +}
> > +
> > +void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
> > +                  void *data)
> > +{
> > +     if (!conn)
> > +             return;
> > +
> > +     mutex_lock(&conn->chan_lock);
> > +     __l2cap_chan_list(conn, func, data);
> > +     mutex_unlock(&conn->chan_lock);
> > +}
> > +
> > +EXPORT_SYMBOL_GPL(l2cap_chan_list);
> > +
> > static void l2cap_conn_update_id_addr(struct work_struct *work)
> > {
> >       struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
> > @@ -1356,29 +1379,79 @@ static void l2cap_le_connect(struct l2cap_chan *chan)
> >                      sizeof(req), &req);
> > }
> >
> > -static void l2cap_ecred_connect(struct l2cap_chan *chan)
> > -{
> > -     struct l2cap_conn *conn = chan->conn;
> > +struct l2cap_ecred_conn_data {
> >       struct {
> >               struct l2cap_ecred_conn_req req;
> > -             __le16 scid;
> > +             __le16 scid[5];
> >       } __packed pdu;
> > +     struct l2cap_chan *chan;
> > +     struct pid *pid;
> > +     int count;
> > +};
> > +
> > +static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data)
> > +{
> > +     struct l2cap_ecred_conn_data *conn = data;
> > +     struct pid *pid;
> > +
> > +     if (chan == conn->chan)
> > +             return;
> > +
> > +     if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags))
> > +             return;
> > +
> > +     pid = chan->ops->get_peer_pid(chan);
> > +
> > +     /* Only add deferred channels with the same PID/PSM */
> > +     if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident ||
> > +         chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
> > +             return;
> > +
> > +     if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
> > +             return;
> > +
> > +     l2cap_ecred_init(chan, 0);
> > +
> > +     /* Set the same ident so we can match on the rsp */
> > +     chan->ident = conn->chan->ident;
> > +
> > +     /* Include all channels deferred */
> > +     conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid);
> > +
> > +     conn->count++;
> > +}
> > +
> > +static void l2cap_ecred_connect(struct l2cap_chan *chan)
> > +{
> > +     struct l2cap_conn *conn = chan->conn;
> > +     struct l2cap_ecred_conn_data data;
> > +
> > +     if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
> > +             return;
> >
> >       if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
> >               return;
> >
> >       l2cap_ecred_init(chan, 0);
> >
> > -     pdu.req.psm     = chan->psm;
> > -     pdu.req.mtu     = cpu_to_le16(chan->imtu);
> > -     pdu.req.mps     = cpu_to_le16(chan->mps);
> > -     pdu.req.credits = cpu_to_le16(chan->rx_credits);
> > -     pdu.scid        = cpu_to_le16(chan->scid);
> > +     data.pdu.req.psm     = chan->psm;
> > +     data.pdu.req.mtu     = cpu_to_le16(chan->imtu);
> > +     data.pdu.req.mps     = cpu_to_le16(chan->mps);
> > +     data.pdu.req.credits = cpu_to_le16(chan->rx_credits);
> > +     data.pdu.scid[0]     = cpu_to_le16(chan->scid);
> >
> >       chan->ident = l2cap_get_ident(conn);
> > +     data.pid = chan->ops->get_peer_pid(chan);
> > +
> > +     data.count = 1;
> > +     data.chan = chan;
> > +     data.pid = chan->ops->get_peer_pid(chan);
> > +
> > +     __l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data);
> >
> >       l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ,
> > -                    sizeof(pdu), &pdu);
> > +                    sizeof(data.pdu.req) + data.count * sizeof(__le16),
> > +                    &data.pdu);
> > }
> >
> > static void l2cap_le_start(struct l2cap_chan *chan)
> > @@ -7694,6 +7767,33 @@ static bool is_valid_psm(u16 psm, u8 dst_type) {
> >       return ((psm & 0x0101) == 0x0001);
> > }
> >
> > +struct l2cap_chan_data {
> > +     struct l2cap_chan *chan;
> > +     struct pid *pid;
> > +     int count;
> > +};
> > +
> > +static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data)
> > +{
> > +     struct l2cap_chan_data *d = data;
> > +     struct pid *pid;
> > +
> > +     if (chan == d->chan)
> > +             return;
> > +
> > +     if (!test_bit(FLAG_DEFER_SETUP, &chan->flags))
> > +             return;
> > +
> > +     pid = chan->ops->get_peer_pid(chan);
> > +
> > +     /* Only count deferred channels with the same PID/PSM */
> > +     if (d->pid != pid || chan->psm != d->chan->psm || chan->ident ||
> > +         chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
> > +             return;
> > +
> > +     d->count++;
> > +}
> > +
> > int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
> >                      bdaddr_t *dst, u8 dst_type)
> > {
> > @@ -7813,6 +7913,22 @@ int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
> >               goto done;
> >       }
> >
> > +     if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
> > +             struct l2cap_chan_data data;
> > +
> > +             data.chan = chan;
> > +             data.pid = chan->ops->get_peer_pid(chan);
> > +             data.count = 0;
> > +
> > +             l2cap_chan_list(conn, l2cap_chan_by_pid, &data);
>
> Put an empty line after this. It gives emphasis to the comment.
>
> > +             /* Check if there isn't too many channels being connected */
> > +             if (!(data.count < L2CAP_ECRED_CONN_SCID_MAX - 1)) {
>
> If (data.count > L2CAP_ECRED_CONN_SCID_MIX) ???

We need to take into account the chan itself is not part of the list
yet, so that means data.count + 1 or we initialize the it as 1 a
couple lines before, I will change the logic to use > operation.

> > +                     hci_conn_drop(hcon);
> > +                     err = -EPROTO;
> > +                     goto done;
> > +             }
> > +     }
> > +
> >       mutex_lock(&conn->chan_lock);
> >       l2cap_chan_lock(chan);
>
> Regards
>
> Marcel
>


-- 
Luiz Augusto von Dentz