Re: [PATCH v3 1/5] Bluetooth: advmon offload MSFT add rssi support

From: Marcel Holtmann
Date: Mon Dec 21 2020 - 04:48:41 EST


Hi Archie,

> MSFT needs rssi parameter for monitoring advertisement packet,
> therefore we should supply them from mgmt. This adds a new opcode
> to add advertisement monitor with rssi parameters.
>
> Signed-off-by: Archie Pusaka <apusaka@xxxxxxxxxxxx>
> Reviewed-by: Manish Mandlik <mmandlik@xxxxxxxxxxxx>
> Reviewed-by: Miao-chen Chou <mcchou@xxxxxxxxxxxx>
> Reviewed-by: Yun-Hao Chung <howardchung@xxxxxxxxxx>
>
> ---
>
> Changes in v3:
> * Flips the order of rssi and pattern_count on mgmt struct
>
> Changes in v2:
> * Add a new opcode instead of modifying an existing one
>
> include/net/bluetooth/hci_core.h | 9 +++
> include/net/bluetooth/mgmt.h | 16 ++++++
> net/bluetooth/mgmt.c | 99 ++++++++++++++++++++++++--------
> 3 files changed, 101 insertions(+), 23 deletions(-)
>
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 677a8c50b2ad..8b7cf3620938 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -250,8 +250,17 @@ struct adv_pattern {
> __u8 value[HCI_MAX_AD_LENGTH];
> };
>
> +struct adv_rssi_thresholds {
> + __s8 low_threshold;
> + __s8 high_threshold;
> + __u16 low_threshold_timeout;
> + __u16 high_threshold_timeout;
> + __u8 sampling_period;
> +};
> +
> struct adv_monitor {
> struct list_head patterns;
> + struct adv_rssi_thresholds rssi;
> bool active;
> __u16 handle;
> };
> diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
> index f9a6638e20b3..9917b911a4fb 100644
> --- a/include/net/bluetooth/mgmt.h
> +++ b/include/net/bluetooth/mgmt.h
> @@ -821,6 +821,22 @@ struct mgmt_rp_add_ext_adv_data {
> __u8 instance;
> } __packed;
>
> +struct mgmt_adv_rssi_thresholds {
> + __s8 high_threshold;
> + __le16 high_threshold_timeout;
> + __s8 low_threshold;
> + __le16 low_threshold_timeout;
> + __u8 sampling_period;
> +} __packed;
> +

please indent this in a away that it stays readable.

__s8 a
__le16 b
..

> +#define MGMT_OP_ADD_ADV_PATTERNS_MONITOR_RSSI 0x0056
> +struct mgmt_cp_add_adv_patterns_monitor_rssi {
> + struct mgmt_adv_rssi_thresholds rssi;
> + __u8 pattern_count;
> + struct mgmt_adv_pattern patterns[];
> +} __packed;
> +#define MGMT_ADD_ADV_PATTERNS_MONITOR_RSSI_SIZE 8
> +
> #define MGMT_EV_CMD_COMPLETE 0x0001
> struct mgmt_ev_cmd_complete {
> __le16 opcode;
> diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> index fa0f7a4a1d2f..cd574054aa39 100644
> --- a/net/bluetooth/mgmt.c
> +++ b/net/bluetooth/mgmt.c
> @@ -124,6 +124,7 @@ static const u16 mgmt_commands[] = {
> MGMT_OP_REMOVE_ADV_MONITOR,
> MGMT_OP_ADD_EXT_ADV_PARAMS,
> MGMT_OP_ADD_EXT_ADV_DATA,
> + MGMT_OP_ADD_ADV_PATTERNS_MONITOR_RSSI,
> };
>
> static const u16 mgmt_events[] = {
> @@ -4225,22 +4226,40 @@ static int read_adv_mon_features(struct sock *sk, struct hci_dev *hdev,
> return err;
> }
>
> -static int add_adv_patterns_monitor(struct sock *sk, struct hci_dev *hdev,
> - void *data, u16 len)
> +static int __add_adv_patterns_monitor(struct sock *sk, struct hci_dev *hdev,
> + void *data, u16 len, u16 op)
> {
> - struct mgmt_cp_add_adv_patterns_monitor *cp = data;
> + struct mgmt_cp_add_adv_patterns_monitor *cp = NULL;
> + struct mgmt_cp_add_adv_patterns_monitor_rssi *cp_rssi = NULL;
> struct mgmt_rp_add_adv_patterns_monitor rp;
> + struct mgmt_adv_rssi_thresholds *rssi = NULL;
> + struct mgmt_adv_pattern *patterns = NULL;
> struct adv_monitor *m = NULL;
> struct adv_pattern *p = NULL;
> unsigned int mp_cnt = 0, prev_adv_monitors_cnt;
> __u8 cp_ofst = 0, cp_len = 0;
> int err, i;
> + u8 pattern_count;
> + u16 expected_len;
>
> BT_DBG("request for %s", hdev->name);
>
> - if (len <= sizeof(*cp) || cp->pattern_count == 0) {
> - err = mgmt_cmd_status(sk, hdev->id,
> - MGMT_OP_ADD_ADV_PATTERNS_MONITOR,
> + if (op == MGMT_OP_ADD_ADV_PATTERNS_MONITOR_RSSI) {
> + cp_rssi = data;
> + pattern_count = cp_rssi->pattern_count;
> + rssi = &cp_rssi->rssi;
> + patterns = cp_rssi->patterns;
> + expected_len = sizeof(*cp_rssi) +
> + pattern_count * sizeof(*patterns);
> + } else {
> + cp = data;
> + pattern_count = cp->pattern_count;
> + patterns = cp->patterns;
> + expected_len = sizeof(*cp) + pattern_count * sizeof(*patterns);
> + }
> +
> + if (len != expected_len || pattern_count == 0) {
> + err = mgmt_cmd_status(sk, hdev->id, op,
> MGMT_STATUS_INVALID_PARAMS);
> goto failed;
> }
> @@ -4254,21 +4273,40 @@ static int add_adv_patterns_monitor(struct sock *sk, struct hci_dev *hdev,
> INIT_LIST_HEAD(&m->patterns);
> m->active = false;
>
> - for (i = 0; i < cp->pattern_count; i++) {
> + if (rssi) {
> + m->rssi.low_threshold = rssi->low_threshold;
> + m->rssi.low_threshold_timeout =
> + __le16_to_cpu(rssi->low_threshold_timeout);
> + m->rssi.high_threshold = rssi->high_threshold;
> + m->rssi.high_threshold_timeout =
> + __le16_to_cpu(rssi->high_threshold_timeout);
> + m->rssi.sampling_period = rssi->sampling_period;
> + } else {
> + /* Default values. These numbers are the least constricting
> + * parameters for MSFT API to work, so it behaves as if there
> + * are no rssi parameter to consider. May need to be changed
> + * if other API are to be supported.
> + */
> + m->rssi.low_threshold = -127;
> + m->rssi.low_threshold_timeout = 60;
> + m->rssi.high_threshold = -127;
> + m->rssi.high_threshold_timeout = 0;
> + m->rssi.sampling_period = 0;
> + }
> +
> + for (i = 0; i < pattern_count; i++) {
> if (++mp_cnt > HCI_MAX_ADV_MONITOR_NUM_PATTERNS) {
> - err = mgmt_cmd_status(sk, hdev->id,
> - MGMT_OP_ADD_ADV_PATTERNS_MONITOR,
> + err = mgmt_cmd_status(sk, hdev->id, op,
> MGMT_STATUS_INVALID_PARAMS);
> goto failed;
> }
>
> - cp_ofst = cp->patterns[i].offset;
> - cp_len = cp->patterns[i].length;
> + cp_ofst = patterns[i].offset;
> + cp_len = patterns[i].length;
> if (cp_ofst >= HCI_MAX_AD_LENGTH ||
> cp_len > HCI_MAX_AD_LENGTH ||
> (cp_ofst + cp_len) > HCI_MAX_AD_LENGTH) {
> - err = mgmt_cmd_status(sk, hdev->id,
> - MGMT_OP_ADD_ADV_PATTERNS_MONITOR,
> + err = mgmt_cmd_status(sk, hdev->id, op,
> MGMT_STATUS_INVALID_PARAMS);
> goto failed;
> }
> @@ -4279,18 +4317,17 @@ static int add_adv_patterns_monitor(struct sock *sk, struct hci_dev *hdev,
> goto failed;
> }
>
> - p->ad_type = cp->patterns[i].ad_type;
> - p->offset = cp->patterns[i].offset;
> - p->length = cp->patterns[i].length;
> - memcpy(p->value, cp->patterns[i].value, p->length);
> + p->ad_type = patterns[i].ad_type;
> + p->offset = patterns[i].offset;
> + p->length = patterns[i].length;
> + memcpy(p->value, patterns[i].value, p->length);
>
> INIT_LIST_HEAD(&p->list);
> list_add(&p->list, &m->patterns);
> }
>
> - if (mp_cnt != cp->pattern_count) {
> - err = mgmt_cmd_status(sk, hdev->id,
> - MGMT_OP_ADD_ADV_PATTERNS_MONITOR,
> + if (mp_cnt != pattern_count) {
> + err = mgmt_cmd_status(sk, hdev->id, op,
> MGMT_STATUS_INVALID_PARAMS);
> goto failed;
> }
> @@ -4302,8 +4339,7 @@ static int add_adv_patterns_monitor(struct sock *sk, struct hci_dev *hdev,
> err = hci_add_adv_monitor(hdev, m);
> if (err) {
> if (err == -ENOSPC) {
> - mgmt_cmd_status(sk, hdev->id,
> - MGMT_OP_ADD_ADV_PATTERNS_MONITOR,
> + mgmt_cmd_status(sk, hdev->id, op,
> MGMT_STATUS_NO_RESOURCES);
> }
> goto unlock;
> @@ -4316,7 +4352,7 @@ static int add_adv_patterns_monitor(struct sock *sk, struct hci_dev *hdev,
>
> rp.monitor_handle = cpu_to_le16(m->handle);
>
> - return mgmt_cmd_complete(sk, hdev->id, MGMT_OP_ADD_ADV_PATTERNS_MONITOR,
> + return mgmt_cmd_complete(sk, hdev->id, op,
> MGMT_STATUS_SUCCESS, &rp, sizeof(rp));
>
> unlock:
> @@ -4327,6 +4363,20 @@ static int add_adv_patterns_monitor(struct sock *sk, struct hci_dev *hdev,
> return err;
> }
>
> +static int add_adv_patterns_monitor(struct sock *sk, struct hci_dev *hdev,
> + void *data, u16 len)
> +{
> + return __add_adv_patterns_monitor(sk, hdev, data, len,
> + MGMT_OP_ADD_ADV_PATTERNS_MONITOR);
> +}
> +
> +static int add_adv_patterns_monitor_rssi(struct sock *sk, struct hci_dev *hdev,
> + void *data, u16 len)
> +{
> + return __add_adv_patterns_monitor(sk, hdev, data, len,
> + MGMT_OP_ADD_ADV_PATTERNS_MONITOR_RSSI);
> +}
> +

Is this really the best way to handle this. I would put the parameter parsing into these functions and then call the common function.

> static int remove_adv_monitor(struct sock *sk, struct hci_dev *hdev,
> void *data, u16 len)
> {
> @@ -8234,6 +8284,9 @@ static const struct hci_mgmt_handler mgmt_handlers[] = {
> HCI_MGMT_VAR_LEN },
> { add_ext_adv_data, MGMT_ADD_EXT_ADV_DATA_SIZE,
> HCI_MGMT_VAR_LEN },
> + { add_adv_patterns_monitor_rssi,
> + MGMT_ADD_ADV_PATTERNS_MONITOR_RSSI_SIZE,
> + HCI_MGMT_VAR_LEN },
> };

Regards

Marcel