Enable use of L2CAP_MODE_EXT_FLOWCTL

This adds a callback to read the socket pid.

Signed-off-by Luiz Augusto von Dentz <[email protected]>

---
include/net/bluetooth/l2cap.h | 1 +
net/bluetooth/l2cap_sock.c | 8 ++++++++

2 files changed, 9 insertions(+)

This uses the DEFER_SETUP flag to group channels with L2CAP_CREDIT_BASED_CONNECTION_REQ.

Signed-off-by Luiz Augusto von Dentz <[email protected]>

---
include/net/bluetooth/l2cap.h | 4 +
net/bluetooth/l2cap_core.c | 136 +++++++++++++++++++++++++++++++---

2 files changed, 130 insertions(+), 10 deletions(-)

include/net/bluetooth/l2cap.h +4 -0

index 2d7d28474d34..dada14d0622c 100644
@@ -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);

net/bluetooth/l2cap_core.c +110 -10

index 5e6e35ab44dd..9f699d09d973 100644
@@ -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;

Hi Luiz,

Quoted 191 lines

This uses the DEFER_SETUP flag to group channels with L2CAP_CREDIT_BASED_CONNECTION_REQ.

Signed-off-by Luiz Augusto von Dentz <[email protected]>

---
include/net/bluetooth/l2cap.h | 4 +
net/bluetooth/l2cap_core.c | 136 +++++++++++++++++++++++++++++++---

2 files changed, 130 insertions(+), 10 deletions(-)

include/net/bluetooth/l2cap.h +4 -0

index 2d7d28474d34..dada14d0622c 100644
@@ -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);

net/bluetooth/l2cap_core.c +110 -10

index 5e6e35ab44dd..9f699d09d973 100644
@@ -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;

net/bluetooth/l2cap_core.c int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid, · line 7923

Quoted 10 lines

net/bluetooth/l2cap_core.c +8 -0

      }
 
+     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.

net/bluetooth/l2cap_core.c int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid, · line 7925

Quoted 2 lines

net/bluetooth/l2cap_core.c +2 -0

+             /* 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) ???

net/bluetooth/l2cap_core.c int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid, · line 7933

Quoted 8 lines

net/bluetooth/l2cap_core.c +6 -0

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

Regards

Marcel

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 <[email protected]>

---

include/net/bluetooth/bluetooth.h |   8 ++
include/net/bluetooth/l2cap.h     |   6 ++
net/bluetooth/l2cap_sock.c        | 124 ++++++++++++++++++++++++++++++
3 files changed, 138 insertions(+)

include/net/bluetooth/bluetooth.h +8 -0

index 1576353a2773..3fa7b1e3c5d9 100644
@@ -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)

include/net/bluetooth/l2cap.h +1 -0

index dada14d0622c..56f727ba23bd 100644
@@ -720,9 +720,15 @@ struct l2cap_user {
 /* ----- L2CAP socket info ----- */
 #define l2cap_pi(sk) ((struct l2cap_pinfo *) sk)
 
+#define L2CAP_PI_OPTION_UNSET		0x00

Hi Luiz,

Quoted 38 lines

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 <[email protected]>

---

include/net/bluetooth/bluetooth.h |   8 ++
include/net/bluetooth/l2cap.h     |   6 ++
net/bluetooth/l2cap_sock.c        | 124 ++++++++++++++++++++++++++++++
3 files changed, 138 insertions(+)

include/net/bluetooth/bluetooth.h +8 -0

index 1576353a2773..3fa7b1e3c5d9 100644
@@ -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)

include/net/bluetooth/l2cap.h +0 -0

index dada14d0622c..56f727ba23bd 100644
@@ -720,9 +720,15 @@ struct l2cap_user {
 /* ----- L2CAP socket info ----- */
 #define l2cap_pi(sk) ((struct l2cap_pinfo *) sk)
 

include/net/bluetooth/l2cap.h struct l2cap_user { · line 733

Quoted 11 lines

include/net/bluetooth/l2cap.h +6 -0

+#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

Quoted 38 lines

Quoted 38 lines

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 <[email protected]>

---

include/net/bluetooth/bluetooth.h |   8 ++
include/net/bluetooth/l2cap.h     |   6 ++
net/bluetooth/l2cap_sock.c        | 124 ++++++++++++++++++++++++++++++
3 files changed, 138 insertions(+)

include/net/bluetooth/bluetooth.h +8 -0

index 1576353a2773..3fa7b1e3c5d9 100644
@@ -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)

include/net/bluetooth/l2cap.h +0 -0

index dada14d0622c..56f727ba23bd 100644
@@ -720,9 +720,15 @@ struct l2cap_user {
 /* ----- L2CAP socket info ----- */
 #define l2cap_pi(sk) ((struct l2cap_pinfo *) sk)
 

Quoted 13 lines

include/net/bluetooth/l2cap.h struct l2cap_user { · line 733

Quoted 11 lines

include/net/bluetooth/l2cap.h +6 -0

+#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.

Quoted 3 lines

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.