Re: [PATCH v4 4/4] Bluetooth: Support the quality report events

From: Marcel Holtmann
Date: Fri Jul 30 2021 - 10:27:44 EST


Hi Joseph,

> This patch allows a user space process to enable/disable the quality
> report events dynamically through the set experimental feature mgmt
> interface if CONFIG_BT_FEATURE_QUALITY_REPORT is enabled.
>
> Since the quality report feature needs to invoke the callback function
> provided by the driver, i.e., hdev->set_quality_report, a valid
> controller index is required.
>
> Reviewed-by: Miao-chen Chou <mcchou@xxxxxxxxxxxx>
> Signed-off-by: Joseph Hwang <josephsih@xxxxxxxxxxxx>
> ---
>
> (no changes since v1)
>
> include/net/bluetooth/hci.h | 4 ++
> include/net/bluetooth/hci_core.h | 22 ++++--
> net/bluetooth/Kconfig | 11 +++
> net/bluetooth/mgmt.c | 118 ++++++++++++++++++++++++++++++-
> 4 files changed, 148 insertions(+), 7 deletions(-)
>
> diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
> index b80415011dcd..2811b60e1acc 100644
> --- a/include/net/bluetooth/hci.h
> +++ b/include/net/bluetooth/hci.h
> @@ -331,6 +331,10 @@ enum {
> HCI_CMD_PENDING,
> HCI_FORCE_NO_MITM,
>
> +#ifdef CONFIG_BT_FEATURE_QUALITY_REPORT
> + HCI_QUALITY_REPORT,
> +#endif
> +
> __HCI_NUM_FLAGS,
> };
>
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index a53e94459ecd..c25de25a7036 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -605,6 +605,9 @@ struct hci_dev {
> int (*set_bdaddr)(struct hci_dev *hdev, const bdaddr_t *bdaddr);
> void (*cmd_timeout)(struct hci_dev *hdev);
> bool (*prevent_wake)(struct hci_dev *hdev);
> +#ifdef CONFIG_BT_FEATURE_QUALITY_REPORT
> + int (*set_quality_report)(struct hci_dev *hdev, bool enable);
> +#endif
> };
>
> #define HCI_PHY_HANDLE(handle) (handle & 0xff)
> @@ -752,12 +755,19 @@ extern struct mutex hci_cb_list_lock;
> #define hci_dev_test_and_clear_flag(hdev, nr) test_and_clear_bit((nr), (hdev)->dev_flags)
> #define hci_dev_test_and_change_flag(hdev, nr) test_and_change_bit((nr), (hdev)->dev_flags)
>
> -#define hci_dev_clear_volatile_flags(hdev) \
> - do { \
> - hci_dev_clear_flag(hdev, HCI_LE_SCAN); \
> - hci_dev_clear_flag(hdev, HCI_LE_ADV); \
> - hci_dev_clear_flag(hdev, HCI_LL_RPA_RESOLUTION);\
> - hci_dev_clear_flag(hdev, HCI_PERIODIC_INQ); \
> +#ifdef CONFIG_BT_FEATURE_QUALITY_REPORT
> +#define hci_dev_clear_flag_quality_report(x) { hci_dev_clear_flag(hdev, x); }
> +#else
> +#define hci_dev_clear_flag_quality_report(x) {}
> +#endif
> +
> +#define hci_dev_clear_volatile_flags(hdev) \
> + do { \
> + hci_dev_clear_flag(hdev, HCI_LE_SCAN); \
> + hci_dev_clear_flag(hdev, HCI_LE_ADV); \
> + hci_dev_clear_flag(hdev, HCI_LL_RPA_RESOLUTION); \
> + hci_dev_clear_flag(hdev, HCI_PERIODIC_INQ); \
> + hci_dev_clear_flag_quality_report(HCI_QUALITY_REPORT) \
> } while (0)
>

we are not doing a CONFIG_BT_FEATURE_QUALITY_REPORT here then. This is getting out of control. What is the harm of always adding this feature? I don’t see a large size impact.

> /* ----- HCI interface to upper protocols ----- */
> diff --git a/net/bluetooth/Kconfig b/net/bluetooth/Kconfig
> index e0ab4cd7afc3..d63c3cdf2d6f 100644
> --- a/net/bluetooth/Kconfig
> +++ b/net/bluetooth/Kconfig
> @@ -148,4 +148,15 @@ config BT_FEATURE_DEBUG
> This provides an option to enable/disable debugging statements
> at runtime via the experimental features interface.
>
> +config BT_FEATURE_QUALITY_REPORT
> + bool "Runtime option for logging controller quality report events"
> + depends on BT
> + default n
> + help
> + This provides an option to enable/disable controller quality report
> + events logging at runtime via the experimental features interface.
> + The quality report events may include the categories of system
> + exceptions, connections/disconnection, the link quality statistics,
> + etc.
> +
> source "drivers/bluetooth/Kconfig"
> diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> index d1bf5a55ff85..0de089524d74 100644
> --- a/net/bluetooth/mgmt.c
> +++ b/net/bluetooth/mgmt.c
> @@ -3791,6 +3791,14 @@ static const u8 debug_uuid[16] = {
> };
> #endif
>
> +#ifdef CONFIG_BT_FEATURE_QUALITY_REPORT
> +/* 330859bc-7506-492d-9370-9a6f0614037f */
> +static const u8 quality_report_uuid[16] = {
> + 0x7f, 0x03, 0x14, 0x06, 0x6f, 0x9a, 0x70, 0x93,
> + 0x2d, 0x49, 0x06, 0x75, 0xbc, 0x59, 0x08, 0x33,
> +};
> +#endif
> +
> /* 671b10b5-42c0-4696-9227-eb28d1b049d6 */
> static const u8 simult_central_periph_uuid[16] = {
> 0xd6, 0x49, 0xb0, 0xd1, 0x28, 0xeb, 0x27, 0x92,
> @@ -3806,7 +3814,7 @@ static const u8 rpa_resolution_uuid[16] = {
> static int read_exp_features_info(struct sock *sk, struct hci_dev *hdev,
> void *data, u16 data_len)
> {
> - char buf[62]; /* Enough space for 3 features */
> + char buf[82]; /* Enough space for 4 features: 2 + 20 * 4 */
> struct mgmt_rp_read_exp_features_info *rp = (void *)buf;
> u16 idx = 0;
> u32 flags;
> @@ -3850,6 +3858,26 @@ static int read_exp_features_info(struct sock *sk, struct hci_dev *hdev,
> idx++;
> }
>
> +#ifdef CONFIG_BT_FEATURE_QUALITY_REPORT
> + if (hdev) {
> + if (hdev->set_quality_report) {
> + /* BIT(0): indicating if set_quality_report is
> + * supported by controller.
> + */
> + flags = BIT(0);
> +
> + /* BIT(1): indicating if the feature is enabled. */
> + if (hci_dev_test_flag(hdev, HCI_QUALITY_REPORT))
> + flags |= BIT(1);
> + } else {
> + flags = 0;
> + }
> + memcpy(rp->features[idx].uuid, quality_report_uuid, 16);
> + rp->features[idx].flags = cpu_to_le32(flags);
> + idx++;
> + }
> +#endif
> +
> rp->feature_count = cpu_to_le16(idx);
>
> /* After reading the experimental features information, enable
> @@ -3892,6 +3920,23 @@ static int exp_debug_feature_changed(bool enabled, struct sock *skip)
> }
> #endif
>
> +#ifdef CONFIG_BT_FEATURE_QUALITY_REPORT
> +static int exp_quality_report_feature_changed(bool enabled, struct sock *skip)
> +{
> + struct mgmt_ev_exp_feature_changed ev;
> +
> + BT_INFO("enabled %d", enabled);
> +
> + memset(&ev, 0, sizeof(ev));
> + memcpy(ev.uuid, quality_report_uuid, 16);
> + ev.flags = cpu_to_le32(enabled ? BIT(0) : 0);
> +
> + return mgmt_limited_event(MGMT_EV_EXP_FEATURE_CHANGED, NULL,
> + &ev, sizeof(ev),
> + HCI_MGMT_EXP_FEATURE_EVENTS, skip);
> +}
> +#endif
> +
> static int set_exp_feature(struct sock *sk, struct hci_dev *hdev,
> void *data, u16 data_len)
> {
> @@ -4038,6 +4083,77 @@ static int set_exp_feature(struct sock *sk, struct hci_dev *hdev,
> return err;
> }
>
> +#ifdef CONFIG_BT_FEATURE_QUALITY_REPORT
> + if (!memcmp(cp->uuid, quality_report_uuid, 16)) {
> + bool val, changed;
> + int err;
> +
> + /* Command requires to use a valid controller index */
> + if (!hdev)
> + return mgmt_cmd_status(sk, MGMT_INDEX_NONE,
> + MGMT_OP_SET_EXP_FEATURE,
> + MGMT_STATUS_INVALID_INDEX);
> +
> + /* Parameters are limited to a single octet */
> + if (data_len != MGMT_SET_EXP_FEATURE_SIZE + 1)
> + return mgmt_cmd_status(sk, hdev->id,
> + MGMT_OP_SET_EXP_FEATURE,
> + MGMT_STATUS_INVALID_PARAMS);
> +
> + /* Only boolean on/off is supported */
> + if (cp->param[0] != 0x00 && cp->param[0] != 0x01)
> + return mgmt_cmd_status(sk, hdev->id,
> + MGMT_OP_SET_EXP_FEATURE,
> + MGMT_STATUS_INVALID_PARAMS);

You really need somewhere here is hdev->set_quality_report is set.

> +
> + hci_req_sync_lock(hdev);
> +
> + val = !!cp->param[0];
> + changed = (val != hci_dev_test_flag(hdev, HCI_QUALITY_REPORT));
> +
> + if (!hdev->set_quality_report) {
> + BT_INFO("quality report not supported");
> + err = mgmt_cmd_status(sk, hdev->id,
> + MGMT_OP_SET_EXP_FEATURE,
> + MGMT_STATUS_NOT_SUPPORTED);
> + goto unlock_quality_report;
> + }
> +
> + if (changed) {
> + err = hdev->set_quality_report(hdev, val);
> + if (err) {
> + BT_ERR("set_quality_report value %d err %d",
> + val, err);
> + err = mgmt_cmd_status(sk, hdev->id,
> + MGMT_OP_SET_EXP_FEATURE,
> + MGMT_STATUS_FAILED);
> + goto unlock_quality_report;
> + }
> + if (val)
> + hci_dev_set_flag(hdev, HCI_QUALITY_REPORT);
> + else
> + hci_dev_clear_flag(hdev, HCI_QUALITY_REPORT);
> + }
> +
> + BT_INFO("quality report enable %d changed %d",
> + val, changed);
> +
> + memcpy(rp.uuid, quality_report_uuid, 16);
> + rp.flags = cpu_to_le32(val ? BIT(0) : 0);
> + hci_sock_set_flag(sk, HCI_MGMT_EXP_FEATURE_EVENTS);
> + err = mgmt_cmd_complete(sk, hdev->id,
> + MGMT_OP_SET_EXP_FEATURE, 0,
> + &rp, sizeof(rp));
> +
> + if (changed)
> + exp_quality_report_feature_changed(val, sk);
> +
> +unlock_quality_report:
> + hci_req_sync_unlock(hdev);
> + return err;
> + }
> +#endif
> +
> return mgmt_cmd_status(sk, hdev ? hdev->id : MGMT_INDEX_NONE,
> MGMT_OP_SET_EXP_FEATURE,
> MGMT_STATUS_NOT_SUPPORTED);

Regards

Marcel