Commit e625e50c authored by Marcel Holtmann's avatar Marcel Holtmann
Browse files

Bluetooth: Introduce debug feature when dynamic debug is disabled 



In case dynamic debug is disabled, this feature allows a vendor platform
to provide debug statement printing.

Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: default avatarJohan Hedberg <johan.hedberg@intel.com>
parent a10c907c

include/net/bluetooth/bluetooth.h

+11 −0
Original line number Diff line number Diff line
@@ -153,6 +153,12 @@ __printf(1, 2) 
void bt_warn(const char *fmt, ...);

__printf(1, 2)

void bt_err(const char *fmt, ...);

#if IS_ENABLED(CONFIG_BT_FEATURE_DEBUG)

void bt_dbg_set(bool enable);

bool bt_dbg_get(void);

__printf(1, 2)

void bt_dbg(const char *fmt, ...);

#endif

__printf(1, 2)

void bt_warn_ratelimited(const char *fmt, ...);

__printf(1, 2)
@@ -161,7 +167,12 @@ void bt_err_ratelimited(const char *fmt, ...); 
#define BT_INFO(fmt, ...)	bt_info(fmt "\n", ##__VA_ARGS__)

#define BT_WARN(fmt, ...)	bt_warn(fmt "\n", ##__VA_ARGS__)

#define BT_ERR(fmt, ...)	bt_err(fmt "\n", ##__VA_ARGS__)



#if IS_ENABLED(CONFIG_BT_FEATURE_DEBUG)

#define BT_DBG(fmt, ...)	bt_dbg(fmt "\n", ##__VA_ARGS__)

#else

#define BT_DBG(fmt, ...)	pr_debug(fmt "\n", ##__VA_ARGS__)

#endif



#define bt_dev_info(hdev, fmt, ...)				\

	BT_INFO("%s: " fmt, (hdev)->name, ##__VA_ARGS__)

net/bluetooth/Kconfig

+7 −0
Original line number Diff line number Diff line
@@ -135,4 +135,11 @@ config BT_SELFTEST_SMP 
	  Run test cases for SMP cryptographic functionality, including both

	  legacy SMP as well as the Secure Connections features.



config BT_FEATURE_DEBUG

	bool "Enable runtime option for debugging statements"

	depends on BT && !DYNAMIC_DEBUG

	help

	  This provides an option to enable/disable debugging statements

	  at runtime via the experimental features interface.



source "drivers/bluetooth/Kconfig"

net/bluetooth/lib.c

+33 −0
Original line number Diff line number Diff line
@@ -183,6 +183,39 @@ void bt_err(const char *format, ...) 
}

EXPORT_SYMBOL(bt_err);



#ifdef CONFIG_BT_FEATURE_DEBUG

static bool debug_enable;



void bt_dbg_set(bool enable)

{

	debug_enable = enable;

}



bool bt_dbg_get(void)

{

	return debug_enable;

}



void bt_dbg(const char *format, ...)

{

	struct va_format vaf;

	va_list args;



	if (likely(!debug_enable))

		return;



	va_start(args, format);



	vaf.fmt = format;

	vaf.va = &args;



	printk(KERN_DEBUG pr_fmt("%pV"), &vaf);



	va_end(args);

}

EXPORT_SYMBOL(bt_dbg);

#endif



void bt_warn_ratelimited(const char *format, ...)

{

	struct va_format vaf;

net/bluetooth/mgmt.c

+87 −0
Original line number Diff line number Diff line
@@ -3715,6 +3715,14 @@ static int read_security_info(struct sock *sk, struct hci_dev *hdev, 
				 rp, sizeof(*rp) + sec_len);

}



#ifdef CONFIG_BT_FEATURE_DEBUG

/* d4992530-b9ec-469f-ab01-6c481c47da1c */

static const u8 debug_uuid[16] = {

	0x1c, 0xda, 0x47, 0x1c, 0x48, 0x6c, 0x01, 0xab,

	0x9f, 0x46, 0xec, 0xb9, 0x30, 0x25, 0x99, 0xd4,

};

#endif



static int read_exp_features_info(struct sock *sk, struct hci_dev *hdev,

				  void *data, u16 data_len)

{
@@ -3726,6 +3734,16 @@ static int read_exp_features_info(struct sock *sk, struct hci_dev *hdev, 


	memset(&buf, 0, sizeof(buf));



#ifdef CONFIG_BT_FEATURE_DEBUG

	if (!hdev) {

		u32 flags = bt_dbg_get() ? BIT(0) : 0;



		memcpy(rp->features[idx].uuid, debug_uuid, 16);

		rp->features[idx].flags = cpu_to_le32(flags);

		idx++;

	}

#endif



	rp->feature_count = cpu_to_le16(idx);



	/* After reading the experimental features information, enable
@@ -3738,6 +3756,21 @@ static int read_exp_features_info(struct sock *sk, struct hci_dev *hdev, 
				 0, rp, sizeof(*rp) + (20 * idx));

}



#ifdef CONFIG_BT_FEATURE_DEBUG

static int exp_debug_feature_changed(bool enabled, struct sock *skip)

{

	struct mgmt_ev_exp_feature_changed ev;



	memset(&ev, 0, sizeof(ev));

	memcpy(ev.uuid, debug_uuid, 16);

	ev.flags = cpu_to_le32(enabled ? BIT(0) : 0);



	return mgmt_limited_event(MGMT_EV_EXP_FEATURE_CHANGED, NULL,

				  &ev, sizeof(ev),

				  HCI_MGMT_EXP_FEATURE_EVENTS, skip);

}

#endif



static int set_exp_feature(struct sock *sk, struct hci_dev *hdev,

			   void *data, u16 data_len)

{
@@ -3750,6 +3783,17 @@ static int set_exp_feature(struct sock *sk, struct hci_dev *hdev, 
		memset(rp.uuid, 0, 16);

		rp.flags = cpu_to_le32(0);



#ifdef CONFIG_BT_FEATURE_DEBUG

		if (!hdev) {

			bool changed = bt_dbg_get();



			bt_dbg_set(false);



			if (changed)

				exp_debug_feature_changed(false, sk);

		}

#endif



		hci_sock_set_flag(sk, HCI_MGMT_EXP_FEATURE_EVENTS);



		return mgmt_cmd_complete(sk, hdev ? hdev->id : MGMT_INDEX_NONE,
@@ -3757,6 +3801,49 @@ static int set_exp_feature(struct sock *sk, struct hci_dev *hdev, 
					 &rp, sizeof(rp));

	}



#ifdef CONFIG_BT_FEATURE_DEBUG

	if (!memcmp(cp->uuid, debug_uuid, 16)) {

		bool val, changed;

		int err;



		/* Command requires to use the non-controller index */

		if (hdev)

			return mgmt_cmd_status(sk, hdev->id,

					       MGMT_OP_SET_EXP_FEATURE,

					       MGMT_STATUS_INVALID_INDEX);



		/* Parameters are limited to a single octet */

		if (data_len != MGMT_SET_EXP_FEATURE_SIZE + 1)

			return mgmt_cmd_status(sk, MGMT_INDEX_NONE,

					       MGMT_OP_SET_EXP_FEATURE,

					       MGMT_STATUS_INVALID_PARAMS);



		/* Only boolean on/off is supported */

		if (cp->param[0] != 0x00 && cp->param[0] != 0x01)

			return mgmt_cmd_status(sk, MGMT_INDEX_NONE,

					       MGMT_OP_SET_EXP_FEATURE,

					       MGMT_STATUS_INVALID_PARAMS);



		val = !!cp->param[0];

		changed = val ? !bt_dbg_get() : bt_dbg_get();

		bt_dbg_set(val);



		memcpy(rp.uuid, debug_uuid, 16);

		rp.flags = cpu_to_le32(val ? BIT(0) : 0);



		hci_sock_set_flag(sk, HCI_MGMT_EXP_FEATURE_EVENTS);



		err = mgmt_cmd_complete(sk, MGMT_INDEX_NONE,

					MGMT_OP_SET_EXP_FEATURE, 0,

					&rp, sizeof(rp));



		if (changed)

			exp_debug_feature_changed(val, sk);



		return err;

	}

#endif



	return mgmt_cmd_status(sk, hdev ? hdev->id : MGMT_INDEX_NONE,

			       MGMT_OP_SET_EXP_FEATURE,

			       MGMT_STATUS_NOT_SUPPORTED);