From e625e50ceee18bc1e3fb1a6375e089405a797a4d Mon Sep 17 00:00:00 2001 From: Marcel Holtmann Date: Wed, 6 May 2020 09:57:52 +0200 Subject: [PATCH] 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: Marcel Holtmann Signed-off-by: Johan Hedberg --- include/net/bluetooth/bluetooth.h | 11 +++++ net/bluetooth/Kconfig | 7 ++++ net/bluetooth/lib.c | 33 +++++++++++++++ net/bluetooth/mgmt.c | 87 +++++++++++++++++++++++++++++++++++++++ 4 files changed, 138 insertions(+) diff --git a/include/net/bluetooth/bluetooth.h b/include/net/bluetooth/bluetooth.h index 3fa7b1e3c5d9..18190055374c 100644 --- a/include/net/bluetooth/bluetooth.h +++ b/include/net/bluetooth/bluetooth.h @@ -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__) diff --git a/net/bluetooth/Kconfig b/net/bluetooth/Kconfig index 9e25c6570170..1d6d243cdde9 100644 --- a/net/bluetooth/Kconfig +++ b/net/bluetooth/Kconfig @@ -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" diff --git a/net/bluetooth/lib.c b/net/bluetooth/lib.c index c09e0a3a0ed9..5326f41a58b7 100644 --- a/net/bluetooth/lib.c +++ b/net/bluetooth/lib.c @@ -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; diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index 3c6be70d98ef..9e8a3cccc6ca 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -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); -- 2.11.0