Bluetooth: Add handler of MGMT_OP_READ_ADV_MONITOR_FEATURES

This adds the request handler of MGMT_OP_READ_ADV_MONITOR_FEATURES
command. Since the controller-based monitoring is not yet in place, this
report only the supported features but not the enabled features.

The following test was performed.
- Issuing btmgmt advmon-features.
Signed-off-by: Miao-chen Chou <mcchou@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

include/net/bluetooth/hci_core.h

@@ -25,6 +25,7 @@
 #ifndef __HCI_CORE_H
 #define __HCI_CORE_H
 
+#include <linux/idr.h>
 #include <linux/leds.h>
 #include <linux/rculist.h>
 
@@ -237,6 +238,24 @@ struct adv_info {
 #define HCI_MAX_ADV_INSTANCES		5
 #define HCI_DEFAULT_ADV_DURATION	2
 
+struct adv_pattern {
+	struct list_head list;
+	__u8 ad_type;
+	__u8 offset;
+	__u8 length;
+	__u8 value[HCI_MAX_AD_LENGTH];
+};
+
+struct adv_monitor {
+	struct list_head patterns;
+	bool		active;
+	__u16		handle;
+};
+
+#define HCI_MIN_ADV_MONITOR_HANDLE		1
+#define HCI_MAX_ADV_MONITOR_NUM_HANDLES	32
+#define HCI_MAX_ADV_MONITOR_NUM_PATTERNS	16
+
 #define HCI_MAX_SHORT_NAME_LENGTH	10
 
 /* Min encryption key size to match with SMP */
@@ -511,6 +530,9 @@ struct hci_dev {
 	__u16			adv_instance_timeout;
 	struct delayed_work	adv_instance_expire;
 
+	struct idr		adv_monitors_idr;
+	unsigned int		adv_monitors_cnt;
+
 	__u8			irk[16];
 	__u32			rpa_timeout;
 	struct delayed_work	rpa_expired;
@@ -1258,6 +1280,8 @@ int hci_add_adv_instance(struct hci_dev *hdev, u8 instance, u32 flags,
 int hci_remove_adv_instance(struct hci_dev *hdev, u8 instance);
 void hci_adv_instances_set_rpa_expired(struct hci_dev *hdev, bool rpa_expired);
 
+void hci_adv_monitors_clear(struct hci_dev *hdev);
+
 void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb);
 
 void hci_init_sysfs(struct hci_dev *hdev);

net/bluetooth/hci_core.c

@@ -26,7 +26,6 @@
 /* Bluetooth HCI core. */
 
 #include <linux/export.h>
-#include <linux/idr.h>
 #include <linux/rfkill.h>
 #include <linux/debugfs.h>
 #include <linux/crypto.h>
@@ -2996,6 +2995,12 @@ int hci_add_adv_instance(struct hci_dev *hdev, u8 instance, u32 flags,
 	return 0;
 }
 
+/* This function requires the caller holds hdev->lock */
+void hci_adv_monitors_clear(struct hci_dev *hdev)
+{
+	idr_destroy(&hdev->adv_monitors_idr);
+}
+
 struct bdaddr_list *hci_bdaddr_list_lookup(struct list_head *bdaddr_list,
 					 bdaddr_t *bdaddr, u8 type)
 {
@@ -3646,6 +3651,8 @@ int hci_register_dev(struct hci_dev *hdev)
 
 	queue_work(hdev->req_workqueue, &hdev->power_on);
 
+	idr_init(&hdev->adv_monitors_idr);
+
 	return id;
 
 err_wqueue:
@@ -3716,6 +3723,7 @@ void hci_unregister_dev(struct hci_dev *hdev)
 	hci_smp_irks_clear(hdev);
 	hci_remote_oob_data_clear(hdev);
 	hci_adv_instances_clear(hdev);
+	hci_adv_monitors_clear(hdev);
 	hci_bdaddr_list_clear(&hdev->le_white_list);
 	hci_bdaddr_list_clear(&hdev->le_resolv_list);
 	hci_conn_params_clear_all(hdev);

net/bluetooth/mgmt.c

@@ -37,6 +37,7 @@
 #include "smp.h"
 #include "mgmt_util.h"
 #include "mgmt_config.h"
+#include "msft.h"
 
 #define MGMT_VERSION	1
 #define MGMT_REVISION	17
@@ -118,6 +119,7 @@ static const u16 mgmt_commands[] = {
 	MGMT_OP_SET_DEF_RUNTIME_CONFIG,
 	MGMT_OP_GET_DEVICE_FLAGS,
 	MGMT_OP_SET_DEVICE_FLAGS,
+	MGMT_OP_READ_ADV_MONITOR_FEATURES,
 };
 
 static const u16 mgmt_events[] = {
@@ -3973,6 +3975,51 @@ static int set_device_flags(struct sock *sk, struct hci_dev *hdev, void *data,
 				 &cp->addr, sizeof(cp->addr));
 }
 
+static int read_adv_mon_features(struct sock *sk, struct hci_dev *hdev,
+				 void *data, u16 len)
+{
+	struct adv_monitor *monitor = NULL;
+	struct mgmt_rp_read_adv_monitor_features *rp = NULL;
+	int handle;
+	size_t rp_size = 0;
+	__u32 supported = 0;
+	__u16 num_handles = 0;
+	__u16 handles[HCI_MAX_ADV_MONITOR_NUM_HANDLES];
+
+	BT_DBG("request for %s", hdev->name);
+
+	hci_dev_lock(hdev);
+
+	if (msft_get_features(hdev) & MSFT_FEATURE_MASK_LE_ADV_MONITOR)
+		supported |= MGMT_ADV_MONITOR_FEATURE_MASK_OR_PATTERNS;
+
+	idr_for_each_entry(&hdev->adv_monitors_idr, monitor, handle) {
+		handles[num_handles++] = monitor->handle;
+	}
+
+	hci_dev_unlock(hdev);
+
+	rp_size = sizeof(*rp) + (num_handles * sizeof(u16));
+	rp = kmalloc(rp_size, GFP_KERNEL);
+	if (!rp)
+		return -ENOMEM;
+
+	/* Once controller-based monitoring is in place, the enabled_features
+	 * should reflect the use.
+	 */
+	rp->supported_features = cpu_to_le32(supported);
+	rp->enabled_features = 0;
+	rp->max_num_handles = cpu_to_le16(HCI_MAX_ADV_MONITOR_NUM_HANDLES);
+	rp->max_num_patterns = HCI_MAX_ADV_MONITOR_NUM_PATTERNS;
+	rp->num_handles = cpu_to_le16(num_handles);
+	if (num_handles)
+		memcpy(&rp->handles, &handles, (num_handles * sizeof(u16)));
+
+	return mgmt_cmd_complete(sk, hdev->id,
+				 MGMT_OP_READ_ADV_MONITOR_FEATURES,
+				 MGMT_STATUS_SUCCESS, rp, rp_size);
+}
+
 static void read_local_oob_data_complete(struct hci_dev *hdev, u8 status,
 				         u16 opcode, struct sk_buff *skb)
 {
@@ -7441,6 +7488,7 @@ static const struct hci_mgmt_handler mgmt_handlers[] = {
 						HCI_MGMT_VAR_LEN },
 	{ get_device_flags,        MGMT_GET_DEVICE_FLAGS_SIZE },
 	{ set_device_flags,        MGMT_SET_DEVICE_FLAGS_SIZE },
+	{ read_adv_mon_features,   MGMT_READ_ADV_MONITOR_FEATURES_SIZE },
 };
 
 void mgmt_index_added(struct hci_dev *hdev)

net/bluetooth/msft.c

@@ -139,3 +139,10 @@ void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb)
 
 	bt_dev_dbg(hdev, "MSFT vendor event %u", event);
 }
+
+__u64 msft_get_features(struct hci_dev *hdev)
+{
+	struct msft_data *msft = hdev->msft_data;
+
+	return  msft ? msft->features : 0;
+}

net/bluetooth/msft.h

@@ -3,16 +3,25 @@
  * Copyright (C) 2020 Google Corporation
  */
 
+#define MSFT_FEATURE_MASK_BREDR_RSSI_MONITOR		BIT(0)
+#define MSFT_FEATURE_MASK_LE_CONN_RSSI_MONITOR		BIT(1)
+#define MSFT_FEATURE_MASK_LE_ADV_RSSI_MONITOR		BIT(2)
+#define MSFT_FEATURE_MASK_LE_ADV_MONITOR		BIT(3)
+#define MSFT_FEATURE_MASK_CURVE_VALIDITY		BIT(4)
+#define MSFT_FEATURE_MASK_CONCURRENT_ADV_MONITOR	BIT(5)
+
 #if IS_ENABLED(CONFIG_BT_MSFTEXT)
 
 void msft_do_open(struct hci_dev *hdev);
 void msft_do_close(struct hci_dev *hdev);
 void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb);
+__u64 msft_get_features(struct hci_dev *hdev);
 
 #else
 
 static inline void msft_do_open(struct hci_dev *hdev) {}
 static inline void msft_do_close(struct hci_dev *hdev) {}
 static inline void msft_vendor_evt(struct hci_dev *hdev, struct sk_buff *skb) {}
+static inline __u64 msft_get_features(struct hci_dev *hdev) { return 0; }
 
 #endif