Re: [PATCH v3 3/3] Bluetooth: Fix stop discovery while in STARTING state

[Marcel Holtmann <marcel@holtmann.org>]

Hi Jaganath,

> 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 d8f68c7..01c723a 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;
> +	u8  discovering;

what is this double spaces for? And why not a bool. Or a better name.

>  	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 0db9d66..6dc275f 100644
> --- a/net/bluetooth/mgmt.c
> +++ b/net/bluetooth/mgmt.c
> @@ -2394,7 +2394,8 @@ 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));
> @@ -2442,6 +2443,10 @@ 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;
> @@ -3720,6 +3725,11 @@ int mgmt_discovering(struct hci_dev *hdev, u8 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;

Regards

Marcel