[PATCH v6 7/7] Bluetooth: disable advertisement filters during suspend

[Archie Pusaka <apusaka@google.com>]

From: Howard Chung <howardchung@google.com>

This adds logic to disable and reenable advertisement filters during
suspend and resume. After this patch, we would only receive packets from
devices in allow list during suspend.

Signed-off-by: Howard Chung <howardchung@google.com>
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
---

Changes in v6:
* New patch "disable advertisement filters during suspend"

 include/net/bluetooth/hci_core.h |  2 ++
 net/bluetooth/hci_request.c      | 29 +++++++++++++++++++++++++++++
 net/bluetooth/msft.c             | 17 ++++++++++++-----
 net/bluetooth/msft.h             |  3 +++
 4 files changed, 46 insertions(+), 5 deletions(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 29cfc6a2d689..fd1d10fe2f11 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -105,6 +105,8 @@ enum suspend_tasks {
 	SUSPEND_POWERING_DOWN,
 
 	SUSPEND_PREPARE_NOTIFIER,
+
+	SUSPEND_SET_ADV_FILTER,
 	__SUSPEND_NUM_TASKS
 };
 
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index d29a44d77b4e..e55976db4403 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -29,6 +29,7 @@
 
 #include "smp.h"
 #include "hci_request.h"
+#include "msft.h"
 
 #define HCI_REQ_DONE	  0
 #define HCI_REQ_PEND	  1
@@ -1242,6 +1243,29 @@ static void suspend_req_complete(struct hci_dev *hdev, u8 status, u16 opcode)
 		clear_bit(SUSPEND_SCAN_DISABLE, hdev->suspend_tasks);
 		wake_up(&hdev->suspend_wait_q);
 	}
+
+	if (test_bit(SUSPEND_SET_ADV_FILTER, hdev->suspend_tasks)) {
+		clear_bit(SUSPEND_SET_ADV_FILTER, hdev->suspend_tasks);
+		wake_up(&hdev->suspend_wait_q);
+	}
+}
+
+static void hci_req_add_set_adv_filter_enable(struct hci_request *req,
+					      bool enable)
+{
+	struct hci_dev *hdev = req->hdev;
+
+	switch (hci_get_adv_monitor_offload_ext(hdev)) {
+	case HCI_ADV_MONITOR_EXT_MSFT:
+		msft_req_add_set_filter_enable(req, enable);
+		break;
+	default:
+		return;
+	}
+
+	/* No need to block when enabling since it's on resume path */
+	if (hdev->suspended && !enable)
+		set_bit(SUSPEND_SET_ADV_FILTER, hdev->suspend_tasks);
 }
 
 /* Call with hci_dev_lock */
@@ -1301,6 +1325,9 @@ void hci_req_prepare_suspend(struct hci_dev *hdev, enum suspended_state next)
 			hci_req_add_le_scan_disable(&req, false);
 		}
 
+		/* Disable advertisement filters */
+		hci_req_add_set_adv_filter_enable(&req, false);
+
 		/* Mark task needing completion */
 		set_bit(SUSPEND_SCAN_DISABLE, hdev->suspend_tasks);
 
@@ -1340,6 +1367,8 @@ void hci_req_prepare_suspend(struct hci_dev *hdev, enum suspended_state next)
 		hci_req_clear_event_filter(&req);
 		/* Reset passive/background scanning to normal */
 		__hci_update_background_scan(&req);
+		/* Enable all of the advertisement filters */
+		hci_req_add_set_adv_filter_enable(&req, true);
 
 		/* Unpause directed advertising */
 		hdev->advertising_paused = false;
diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
index b2ef654b1d3d..47b104f318e9 100644
--- a/net/bluetooth/msft.c
+++ b/net/bluetooth/msft.c
@@ -579,9 +579,19 @@ int msft_remove_monitor(struct hci_dev *hdev, struct adv_monitor *monitor,
 	return err;
 }
 
-int msft_set_filter_enable(struct hci_dev *hdev, bool enable)
+void msft_req_add_set_filter_enable(struct hci_request *req, bool enable)
 {
+	struct hci_dev *hdev = req->hdev;
 	struct msft_cp_le_set_advertisement_filter_enable cp;
+
+	cp.sub_opcode = MSFT_OP_LE_SET_ADVERTISEMENT_FILTER_ENABLE;
+	cp.enable = enable;
+
+	hci_req_add(req, hdev->msft_opcode, sizeof(cp), &cp);
+}
+
+int msft_set_filter_enable(struct hci_dev *hdev, bool enable)
+{
 	struct hci_request req;
 	struct msft_data *msft = hdev->msft_data;
 	int err;
@@ -589,11 +599,8 @@ int msft_set_filter_enable(struct hci_dev *hdev, bool enable)
 	if (!msft)
 		return -EOPNOTSUPP;
 
-	cp.sub_opcode = MSFT_OP_LE_SET_ADVERTISEMENT_FILTER_ENABLE;
-	cp.enable = enable;
-
 	hci_req_init(&req, hdev);
-	hci_req_add(&req, hdev->msft_opcode, sizeof(cp), &cp);
+	msft_req_add_set_filter_enable(&req, enable);
 	err = hci_req_run_skb(&req, msft_le_set_advertisement_filter_enable_cb);
 
 	return err;
diff --git a/net/bluetooth/msft.h b/net/bluetooth/msft.h
index f8e4d3a6d641..88ed613dfa08 100644
--- a/net/bluetooth/msft.h
+++ b/net/bluetooth/msft.h
@@ -20,6 +20,7 @@ __u64 msft_get_features(struct hci_dev *hdev);
 int msft_add_monitor_pattern(struct hci_dev *hdev, struct adv_monitor *monitor);
 int msft_remove_monitor(struct hci_dev *hdev, struct adv_monitor *monitor,
 			u16 handle);
+void msft_req_add_set_filter_enable(struct hci_request *req, bool enable);
 int msft_set_filter_enable(struct hci_dev *hdev, bool enable);
 
 #else
@@ -46,6 +47,8 @@ static inline int msft_remove_monitor(struct hci_dev *hdev,
 	return -EOPNOTSUPP;
 }
 
+static inline void msft_req_add_set_filter_enable(struct hci_request *req,
+						  bool enable) {}
 static inline int msft_set_filter_enable(struct hci_dev *hdev, bool enable)
 {
 	return -EOPNOTSUPP;
-- 
2.30.0.280.ga3ce27912f-goog