[PATCH v5 4/5] Bluetooth: advmon offload MSFT handle controller reset

From: Archie Pusaka
Date: Tue Dec 22 2020 - 05:28:15 EST


From: Archie Pusaka <apusaka@xxxxxxxxxxxx>

When the controller is powered off, the registered advertising monitor
is removed from the controller. This patch handles the re-registration
of those monitors when the power is on.

Signed-off-by: Archie Pusaka <apusaka@xxxxxxxxxxxx>
Reviewed-by: Miao-chen Chou <mcchou@xxxxxxxxxxxx>
Reviewed-by: Yun-Hao Chung <howardchung@xxxxxxxxxx>

---

Changes in v5:
* Discard struct flags on msft_data and use it's members directly

net/bluetooth/msft.c | 76 +++++++++++++++++++++++++++++++++++++++++---
1 file changed, 71 insertions(+), 5 deletions(-)

diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
index f5aa0e3b1b9b..d25c6936daa4 100644
--- a/net/bluetooth/msft.c
+++ b/net/bluetooth/msft.c
@@ -82,8 +82,12 @@ struct msft_data {
struct list_head handle_map;
__u16 pending_add_handle;
__u16 pending_remove_handle;
+ __u8 reregistering;
};

+static int __msft_add_monitor_pattern(struct hci_dev *hdev,
+ struct adv_monitor *monitor);
+
bool msft_monitor_supported(struct hci_dev *hdev)
{
return !!(msft_get_features(hdev) & MSFT_FEATURE_MASK_LE_ADV_MONITOR);
@@ -134,6 +138,35 @@ static bool read_supported_features(struct hci_dev *hdev,
return false;
}

+/* This function requires the caller holds hdev->lock */
+static void reregister_monitor_on_restart(struct hci_dev *hdev, int handle)
+{
+ struct adv_monitor *monitor;
+ struct msft_data *msft = hdev->msft_data;
+ int err;
+
+ while (1) {
+ monitor = idr_get_next(&hdev->adv_monitors_idr, &handle);
+ if (!monitor) {
+ /* All monitors have been reregistered */
+ msft->reregistering = false;
+ hci_update_background_scan(hdev);
+ return;
+ }
+
+ msft->pending_add_handle = (u16)handle;
+ err = __msft_add_monitor_pattern(hdev, monitor);
+
+ /* If success, we return and wait for monitor added callback */
+ if (!err)
+ return;
+
+ /* Otherwise remove the monitor and keep registering */
+ hci_free_adv_monitor(hdev, monitor);
+ handle++;
+ }
+}
+
void msft_do_open(struct hci_dev *hdev)
{
struct msft_data *msft;
@@ -154,12 +187,18 @@ void msft_do_open(struct hci_dev *hdev)

INIT_LIST_HEAD(&msft->handle_map);
hdev->msft_data = msft;
+
+ if (msft_monitor_supported(hdev)) {
+ msft->reregistering = true;
+ reregister_monitor_on_restart(hdev, 0);
+ }
}

void msft_do_close(struct hci_dev *hdev)
{
struct msft_data *msft = hdev->msft_data;
struct msft_monitor_advertisement_handle_data *handle_data, *tmp;
+ struct adv_monitor *monitor;

if (!msft)
return;
@@ -169,6 +208,12 @@ void msft_do_close(struct hci_dev *hdev)
hdev->msft_data = NULL;

list_for_each_entry_safe(handle_data, tmp, &msft->handle_map, list) {
+ monitor = idr_find(&hdev->adv_monitors_idr,
+ handle_data->mgmt_handle);
+
+ if (monitor && monitor->state == ADV_MONITOR_STATE_OFFLOADED)
+ monitor->state = ADV_MONITOR_STATE_REGISTERED;
+
list_del(&handle_data->list);
kfree(handle_data);
}
@@ -282,9 +327,15 @@ static void msft_le_monitor_advertisement_cb(struct hci_dev *hdev,
if (status && monitor)
hci_free_adv_monitor(hdev, monitor);

+ /* If in restart/reregister sequence, keep registering. */
+ if (msft->reregistering)
+ reregister_monitor_on_restart(hdev,
+ msft->pending_add_handle + 1);
+
hci_dev_unlock(hdev);

- hci_add_adv_patterns_monitor_complete(hdev, status);
+ if (!msft->reregistering)
+ hci_add_adv_patterns_monitor_complete(hdev, status);
}

static void msft_le_cancel_monitor_advertisement_cb(struct hci_dev *hdev,
@@ -374,7 +425,8 @@ static bool msft_monitor_pattern_valid(struct adv_monitor *monitor)
}

/* This function requires the caller holds hdev->lock */
-int msft_add_monitor_pattern(struct hci_dev *hdev, struct adv_monitor *monitor)
+static int __msft_add_monitor_pattern(struct hci_dev *hdev,
+ struct adv_monitor *monitor)
{
struct msft_cp_le_monitor_advertisement *cp;
struct msft_le_monitor_advertisement_pattern_data *pattern_data;
@@ -387,9 +439,6 @@ int msft_add_monitor_pattern(struct hci_dev *hdev, struct adv_monitor *monitor)
u8 pattern_count = 0;
int err = 0;

- if (!msft)
- return -EOPNOTSUPP;
-
if (!msft_monitor_pattern_valid(monitor))
return -EINVAL;

@@ -434,6 +483,20 @@ int msft_add_monitor_pattern(struct hci_dev *hdev, struct adv_monitor *monitor)
return err;
}

+/* This function requires the caller holds hdev->lock */
+int msft_add_monitor_pattern(struct hci_dev *hdev, struct adv_monitor *monitor)
+{
+ struct msft_data *msft = hdev->msft_data;
+
+ if (!msft)
+ return -EOPNOTSUPP;
+
+ if (msft->reregistering)
+ return -EBUSY;
+
+ return __msft_add_monitor_pattern(hdev, monitor);
+}
+
/* This function requires the caller holds hdev->lock */
int msft_remove_monitor(struct hci_dev *hdev, struct adv_monitor *monitor,
u16 handle)
@@ -447,6 +510,9 @@ int msft_remove_monitor(struct hci_dev *hdev, struct adv_monitor *monitor,
if (!msft)
return -EOPNOTSUPP;

+ if (msft->reregistering)
+ return -EBUSY;
+
handle_data = msft_find_handle_data(hdev, monitor->handle, true);

/* If no matched handle, just remove without telling controller */
--
2.29.2.729.g45daf8777d-goog