[PATCH v6 4/4] Bluetooth: Add toggle to switch off interleave scan

From: Howard Chung
Date: Mon Sep 28 2020 - 03:41:48 EST


This patch add a configurable parameter to switch off the interleave
scan feature.

Signed-off-by: Howard Chung <howardchung@xxxxxxxxxx>
Reviewed-by: Alain Michaud <alainm@xxxxxxxxxxxx>
---

Changes in v6:
- Change the type of enable_advmon_interleave_scan to u8

Changes in v4:
- Set EnableAdvMonInterleaveScan default to Disable
- Fix 80 chars limit in mgmt_config.c

include/net/bluetooth/hci_core.h | 1 +
net/bluetooth/hci_core.c | 1 +
net/bluetooth/hci_request.c | 3 ++-
net/bluetooth/mgmt_config.c | 39 +++++++++++++++++++++++---------
4 files changed, 32 insertions(+), 12 deletions(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index cfede18709d8f..63c6d656564a1 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -363,6 +363,7 @@ struct hci_dev {
__u32 clock;
__u16 advmon_allowlist_duration;
__u16 advmon_no_filter_duration;
+ __u8 enable_advmon_interleave_scan;

__u16 devid_source;
__u16 devid_vendor;
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 6c8850149265a..c37b2d5395abc 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -3595,6 +3595,7 @@ struct hci_dev *hci_alloc_dev(void)
/* The default values will be chosen in the future */
hdev->advmon_allowlist_duration = 300;
hdev->advmon_no_filter_duration = 500;
+ hdev->enable_advmon_interleave_scan = 0x00; /* Default to disable */

hdev->sniff_max_interval = 800;
hdev->sniff_min_interval = 80;
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index 4048c82d4257f..23381f263678b 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -1057,7 +1057,8 @@ void hci_req_add_le_passive_scan(struct hci_request *req)
&own_addr_type))
return;

- if (__hci_update_interleaved_scan(hdev))
+ if (hdev->enable_advmon_interleave_scan &&
+ __hci_update_interleaved_scan(hdev))
return;

/* Adding or removing entries from the white list must
diff --git a/net/bluetooth/mgmt_config.c b/net/bluetooth/mgmt_config.c
index 2d3ad288c78ac..f7906c5d7f01a 100644
--- a/net/bluetooth/mgmt_config.c
+++ b/net/bluetooth/mgmt_config.c
@@ -17,6 +17,12 @@
{ cpu_to_le16(hdev->_param_name_) } \
}

+#define HDEV_PARAM_U8(_param_code_, _param_name_) \
+{ \
+ { (_param_code_), sizeof(__u8) }, \
+ { hdev->_param_name_ } \
+}
+
#define HDEV_PARAM_U16_JIFFIES_TO_MSECS(_param_code_, _param_name_) \
{ \
{ cpu_to_le16(_param_code_), sizeof(__u16) }, \
@@ -30,11 +36,12 @@ int read_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
struct mgmt_tlv entry;
union {
/* This is a simplification for now since all values
- * are 16 bits. In the future, this code may need
+ * are fixed bits. In the future, this code may need
* refactoring to account for variable length values
* and properly calculate the required buffer size.
*/
- __le16 value;
+ __le16 value_le16;
+ __u8 value_u8;
};
} __packed params[] = {
/* Please see mgmt-api.txt for documentation of these values */
@@ -69,6 +76,7 @@ int read_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
def_le_autoconnect_timeout),
HDEV_PARAM_U16(0x001d, advmon_allowlist_duration),
HDEV_PARAM_U16(0x001e, advmon_no_filter_duration),
+ HDEV_PARAM_U8(0x001f, enable_advmon_interleave_scan),
};
struct mgmt_rp_read_def_system_config *rp = (void *)params;

@@ -81,7 +89,7 @@ int read_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,

#define TO_TLV(x) ((struct mgmt_tlv *)(x))
#define TLV_GET_LE16(tlv) le16_to_cpu(*((__le16 *)(TO_TLV(tlv)->value)))
-
+#define TLV_GET_U8(tlv) (*((__u8 *)(TO_TLV(tlv)->value)))
int set_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
u16 data_len)
{
@@ -100,6 +108,7 @@ int set_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
const u16 exp_len = sizeof(struct mgmt_tlv) +
len;
const u16 type = le16_to_cpu(TO_TLV(buffer)->type);
+ u8 exp_data_len;

if (buffer_left < exp_len) {
bt_dev_warn(hdev, "invalid len left %d, exp >= %d",
@@ -142,20 +151,25 @@ int set_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
case 0x001b:
case 0x001d:
case 0x001e:
- if (len != sizeof(u16)) {
- bt_dev_warn(hdev, "invalid length %d, exp %zu for type %d",
- len, sizeof(u16), type);
-
- return mgmt_cmd_status(sk, hdev->id,
- MGMT_OP_SET_DEF_SYSTEM_CONFIG,
- MGMT_STATUS_INVALID_PARAMS);
- }
+ exp_data_len = sizeof(u16);
+ break;
+ case 0x001f:
+ exp_data_len = sizeof(u8);
break;
default:
bt_dev_warn(hdev, "unsupported parameter %u", type);
break;
}

+ if (len != exp_data_len) {
+ bt_dev_warn(hdev, "invalid length %d, exp %zu for type %d",
+ len, exp_data_len, type);
+
+ return mgmt_cmd_status(sk, hdev->id,
+ MGMT_OP_SET_DEF_SYSTEM_CONFIG,
+ MGMT_STATUS_INVALID_PARAMS);
+ }
+
buffer_left -= exp_len;
buffer += exp_len;
}
@@ -261,6 +275,9 @@ int set_def_system_config(struct sock *sk, struct hci_dev *hdev, void *data,
case 0x0001e:
hdev->advmon_no_filter_duration = TLV_GET_LE16(buffer);
break;
+ case 0x0001f:
+ hdev->enable_advmon_interleave_scan = TLV_GET_U8(buffer);
+ break;
default:
bt_dev_warn(hdev, "unsupported parameter %u", type);
break;
--
2.28.0.681.g6f77f65b4e-goog