[PATCH v4 1/4] Bluetooth: Move discovery state check inside hci_dev_lock()

[PATCH v4 1/4] Bluetooth: Move discovery state check inside hci_dev_lock()

[Jaganath Kanakkassery]

After checking the discovery state, if other thread modifies it
then it will be overwritten by the assignment in the first thread.

Signed-off-by: Jaganath Kanakkassery <jaganath.k@samsung.com>
---
 net/bluetooth/hci_event.c |    9 ++++-----
 net/bluetooth/mgmt.c      |    4 ----
 2 files changed, 4 insertions(+), 9 deletions(-)

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 705078a..97b4828 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -1273,14 +1273,13 @@ static void hci_cc_le_set_scan_enable(struct hci_dev *hdev,
 
 		clear_bit(HCI_LE_SCAN, &hdev->dev_flags);
 
+		hci_dev_lock(hdev);
 		if (hdev->discovery.type == DISCOV_TYPE_INTERLEAVED &&
-		    hdev->discovery.state == DISCOVERY_FINDING) {
+		    hdev->discovery.state == DISCOVERY_FINDING)
 			mgmt_interleaved_discovery(hdev);
-		} else {
-			hci_dev_lock(hdev);
+		else
 			hci_discovery_set_state(hdev, DISCOVERY_STOPPED);
-			hci_dev_unlock(hdev);
-		}
+		hci_dev_unlock(hdev);
 
 		break;
 
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 37add53..a7865ad 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -2333,14 +2333,10 @@ int mgmt_interleaved_discovery(struct hci_dev *hdev)
 
 	BT_DBG("%s", hdev->name);
 
-	hci_dev_lock(hdev);
-
 	err = hci_do_inquiry(hdev, INQUIRY_LEN_BREDR_LE);
 	if (err < 0)
 		hci_discovery_set_state(hdev, DISCOVERY_STOPPED);
 
-	hci_dev_unlock(hdev);
-
 	return err;
 }
 
-- 
1.7.9.5

[PATCH v4 2/4] Bluetooth: Add mgmt_start_discovery_cancelled()

[Jaganath Kanakkassery]

This function can be used to inform userspace that start discovery
is cancelled

Signed-off-by: Jaganath Kanakkassery <jaganath.k@samsung.com>
---
 include/net/bluetooth/hci_core.h |    1 +
 net/bluetooth/mgmt.c             |   19 +++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 014a2ea..d8f68c7 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -1112,6 +1112,7 @@ int mgmt_device_found(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
 int mgmt_remote_name(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
 		     u8 addr_type, s8 rssi, u8 *name, u8 name_len);
 int mgmt_start_discovery_failed(struct hci_dev *hdev, u8 status);
+int mgmt_start_discovery_cancelled(struct hci_dev *hdev);
 int mgmt_stop_discovery_failed(struct hci_dev *hdev, u8 status);
 int mgmt_discovering(struct hci_dev *hdev, u8 discovering);
 int mgmt_interleaved_discovery(struct hci_dev *hdev);
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index a7865ad..3527095 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -3722,6 +3722,25 @@ int mgmt_start_discovery_failed(struct hci_dev *hdev, u8 status)
 	return err;
 }
 
+int mgmt_start_discovery_cancelled(struct hci_dev *hdev)
+{
+	struct pending_cmd *cmd;
+	u8 type;
+	int err;
+
+	cmd = mgmt_pending_find(MGMT_OP_START_DISCOVERY, hdev);
+	if (!cmd)
+		return -ENOENT;
+
+	type = hdev->discovery.type;
+
+	err = cmd_complete(cmd->sk, hdev->id, cmd->opcode, MGMT_STATUS_CANCELLED,
+			   &type, sizeof(type));
+	mgmt_pending_remove(cmd);
+
+	return err;
+}
+
 int mgmt_stop_discovery_failed(struct hci_dev *hdev, u8 status)
 {
 	struct pending_cmd *cmd;
-- 
1.7.9.5

[PATCH v4 3/4] Bluetooth: Change type of "discovering" from u8 to bool

[Jaganath Kanakkassery]

Since the only possible values of discovering is 0 and 1, bool is
more appropriate

Signed-off-by: Jaganath Kanakkassery <jaganath.k@samsung.com>
---
 include/net/bluetooth/hci_core.h |    2 +-
 net/bluetooth/hci_core.c         |    4 ++--
 net/bluetooth/mgmt.c             |    2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index d8f68c7..f20da05 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -1114,7 +1114,7 @@ int mgmt_remote_name(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
 int mgmt_start_discovery_failed(struct hci_dev *hdev, u8 status);
 int mgmt_start_discovery_cancelled(struct hci_dev *hdev);
 int mgmt_stop_discovery_failed(struct hci_dev *hdev, u8 status);
-int mgmt_discovering(struct hci_dev *hdev, u8 discovering);
+int mgmt_discovering(struct hci_dev *hdev, bool discovering);
 int mgmt_interleaved_discovery(struct hci_dev *hdev);
 int mgmt_device_blocked(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 type);
 int mgmt_device_unblocked(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 type);
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 596660d..ce6a696 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -326,12 +326,12 @@ void hci_discovery_set_state(struct hci_dev *hdev, int state)
 	switch (state) {
 	case DISCOVERY_STOPPED:
 		if (hdev->discovery.state != DISCOVERY_STARTING)
-			mgmt_discovering(hdev, 0);
+			mgmt_discovering(hdev, false);
 		break;
 	case DISCOVERY_STARTING:
 		break;
 	case DISCOVERY_FINDING:
-		mgmt_discovering(hdev, 1);
+		mgmt_discovering(hdev, true);
 		break;
 	case DISCOVERY_RESOLVING:
 		break;
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 3527095..ba5ca81 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -3757,7 +3757,7 @@ int mgmt_stop_discovery_failed(struct hci_dev *hdev, u8 status)
 	return err;
 }
 
-int mgmt_discovering(struct hci_dev *hdev, u8 discovering)
+int mgmt_discovering(struct hci_dev *hdev, bool discovering)
 {
 	struct mgmt_ev_discovering ev;
 	struct pending_cmd *cmd;
-- 
1.7.9.5

[PATCH v4 4/4] Bluetooth: Fix stop discovery while in STARTING state

[Jaganath Kanakkassery]

If stop_discovery() is called when discovery state is STARTING, it
will be failed currently. This patch fixes this.

Signed-off-by: Jaganath Kanakkassery <jaganath.k@samsung.com>
---
 include/net/bluetooth/hci_core.h |    1 +
 net/bluetooth/hci_event.c        |   14 ++++++++++++--
 net/bluetooth/mgmt.c             |   12 +++++++++++-
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index f20da05..0a7aa1f 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -64,6 +64,7 @@ struct discovery_state {
 		DISCOVERY_RESOLVING,
 		DISCOVERY_STOPPING,
 	} state;
+	bool discovering;
 	struct list_head	all;	/* All devices found during inquiry */
 	struct list_head	unknown;	/* Name state not known */
 	struct list_head	resolve;	/* Name needs to be resolved */
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 97b4828..c616cbf 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -1259,7 +1259,12 @@ static void hci_cc_le_set_scan_enable(struct hci_dev *hdev,
 		set_bit(HCI_LE_SCAN, &hdev->dev_flags);
 
 		hci_dev_lock(hdev);
-		hci_discovery_set_state(hdev, DISCOVERY_FINDING);
+		if (hdev->discovery.state == DISCOVERY_STOPPING) {
+			hci_cancel_le_scan(hdev);
+			mgmt_start_discovery_cancelled(hdev);
+		} else {
+			hci_discovery_set_state(hdev, DISCOVERY_FINDING);
+		}
 		hci_dev_unlock(hdev);
 		break;
 
@@ -1375,7 +1380,12 @@ static void hci_cs_inquiry(struct hci_dev *hdev, __u8 status)
 	set_bit(HCI_INQUIRY, &hdev->flags);
 
 	hci_dev_lock(hdev);
-	hci_discovery_set_state(hdev, DISCOVERY_FINDING);
+	if (hdev->discovery.state == DISCOVERY_STOPPING) {
+		hci_cancel_inquiry(hdev);
+		mgmt_start_discovery_cancelled(hdev);
+	} else {
+		hci_discovery_set_state(hdev, DISCOVERY_FINDING);
+	}
 	hci_dev_unlock(hdev);
 }
 
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index ba5ca81..d9b1aa1 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -2443,7 +2443,8 @@ static int stop_discovery(struct sock *sk, struct hci_dev *hdev, void *data,
 
 	hci_dev_lock(hdev);
 
-	if (!hci_discovery_active(hdev)) {
+	if (hdev->discovery.state != DISCOVERY_STARTING &&
+	    !hci_discovery_active(hdev)) {
 		err = cmd_complete(sk, hdev->id, MGMT_OP_STOP_DISCOVERY,
 				   MGMT_STATUS_REJECTED, &mgmt_cp->type,
 				   sizeof(mgmt_cp->type));
@@ -2491,6 +2492,10 @@ static int stop_discovery(struct sock *sk, struct hci_dev *hdev, void *data,
 
 		break;
 
+	case DISCOVERY_STARTING:
+		err = 0;
+		break;
+
 	default:
 		BT_DBG("unknown discovery state %u", hdev->discovery.state);
 		err = -EFAULT;
@@ -3777,6 +3782,11 @@ int mgmt_discovering(struct hci_dev *hdev, bool discovering)
 		mgmt_pending_remove(cmd);
 	}
 
+	if (hdev->discovery.discovering == discovering)
+		return 0;
+
+	hdev->discovery.discovering = discovering;
+
 	memset(&ev, 0, sizeof(ev));
 	ev.type = hdev->discovery.type;
 	ev.discovering = discovering;
-- 
1.7.9.5