Bluetooth: Add support for extended index management command

The Read Extended Contoller Index List command can be used for
retrieving the complete list of local available controllers. This
included configured, unconfigured and also AMP controllers.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>

include/net/bluetooth/mgmt.h

@@ -505,6 +505,17 @@ struct mgmt_cp_start_service_discovery {
 } __packed;
 #define MGMT_START_SERVICE_DISCOVERY_SIZE 4
 
+#define MGMT_OP_READ_EXT_INDEX_LIST	0x003C
+#define MGMT_READ_EXT_INDEX_LIST_SIZE	0
+struct mgmt_rp_read_ext_index_list {
+	__le16	num_controllers;
+	struct {
+		__le16 index;
+		__u8   type;
+		__u8   bus;
+	} entry[0];
+} __packed;
+
 #define MGMT_EV_CMD_COMPLETE		0x0001
 struct mgmt_ev_cmd_complete {
 	__le16	opcode;

net/bluetooth/mgmt.c

@@ -96,6 +96,7 @@ static const u16 mgmt_commands[] = {
 	MGMT_OP_SET_EXTERNAL_CONFIG,
 	MGMT_OP_SET_PUBLIC_ADDRESS,
 	MGMT_OP_START_SERVICE_DISCOVERY,
+	MGMT_OP_READ_EXT_INDEX_LIST,
 };
 
 static const u16 mgmt_events[] = {
@@ -518,6 +519,82 @@ static int read_unconf_index_list(struct sock *sk, struct hci_dev *hdev,
 	return err;
 }
 
+static int read_ext_index_list(struct sock *sk, struct hci_dev *hdev,
+			       void *data, u16 data_len)
+{
+	struct mgmt_rp_read_ext_index_list *rp;
+	struct hci_dev *d;
+	size_t rp_len;
+	u16 count;
+	int err;
+
+	BT_DBG("sock %p", sk);
+
+	read_lock(&hci_dev_list_lock);
+
+	count = 0;
+	list_for_each_entry(d, &hci_dev_list, list) {
+		if (d->dev_type == HCI_BREDR || d->dev_type == HCI_AMP)
+			count++;
+	}
+
+	rp_len = sizeof(*rp) + (sizeof(rp->entry[0]) * count);
+	rp = kmalloc(rp_len, GFP_ATOMIC);
+	if (!rp) {
+		read_unlock(&hci_dev_list_lock);
+		return -ENOMEM;
+	}
+
+	count = 0;
+	list_for_each_entry(d, &hci_dev_list, list) {
+		if (hci_dev_test_flag(d, HCI_SETUP) ||
+		    hci_dev_test_flag(d, HCI_CONFIG) ||
+		    hci_dev_test_flag(d, HCI_USER_CHANNEL))
+			continue;
+
+		/* Devices marked as raw-only are neither configured
+		 * nor unconfigured controllers.
+		 */
+		if (test_bit(HCI_QUIRK_RAW_DEVICE, &d->quirks))
+			continue;
+
+		if (d->dev_type == HCI_BREDR) {
+			if (hci_dev_test_flag(d, HCI_UNCONFIGURED))
+				rp->entry[count].type = 0x01;
+			else
+				rp->entry[count].type = 0x00;
+		} else if (d->dev_type == HCI_AMP) {
+			rp->entry[count].type = 0x02;
+		} else {
+			continue;
+		}
+
+		rp->entry[count].bus = d->bus;
+		rp->entry[count++].index = cpu_to_le16(d->id);
+		BT_DBG("Added hci%u", d->id);
+	}
+
+	rp->num_controllers = cpu_to_le16(count);
+	rp_len = sizeof(*rp) + (sizeof(rp->entry[0]) * count);
+
+	read_unlock(&hci_dev_list_lock);
+
+	/* If this command is called at least once, then all the
+	 * default index and unconfigured index events are disabled
+	 * and from now on only extended index events are used.
+	 */
+	hci_sock_set_flag(sk, HCI_MGMT_EXT_INDEX_EVENTS);
+	hci_sock_clear_flag(sk, HCI_MGMT_INDEX_EVENTS);
+	hci_sock_clear_flag(sk, HCI_MGMT_UNCONF_INDEX_EVENTS);
+
+	err = mgmt_cmd_complete(sk, MGMT_INDEX_NONE,
+				MGMT_OP_READ_EXT_INDEX_LIST, 0, rp, rp_len);
+
+	kfree(rp);
+
+	return err;
+}
+
 static bool is_configured(struct hci_dev *hdev)
 {
 	if (test_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks) &&
@@ -6264,6 +6341,9 @@ static const struct hci_mgmt_handler mgmt_handlers[] = {
 						HCI_MGMT_UNCONFIGURED },
 	{ start_service_discovery, MGMT_START_SERVICE_DISCOVERY_SIZE,
 						HCI_MGMT_VAR_LEN },
+	{ NULL },
+	{ read_ext_index_list,     MGMT_READ_EXT_INDEX_LIST_SIZE,
+						HCI_MGMT_NO_HDEV },
 };
 
 int mgmt_control(struct hci_mgmt_chan *chan, struct sock *sk,