2011-02-14 11:36:12

by Ville Tervo

[permalink] [raw]
Subject: [PATCH v2] Bluetooth: Use proper timer for hci command timout

From: Ville Tervo <[email protected]>

Use proper timer instead of hci command flow control to timeout
failed hci commands. Otherwise stack ends up sending commands
when flow control is used to block new commands.

2010-09-01 18:29:41.592132 < HCI Command: Remote Name Request (0x01|0x0019) plen 10
bdaddr 00:16:CF:E1:C7:D7 mode 2 clkoffset 0x0000
2010-09-01 18:29:41.592681 > HCI Event: Command Status (0x0f) plen 4
Remote Name Request (0x01|0x0019) status 0x00 ncmd 0
2010-09-01 18:29:51.022033 < HCI Command: Remote Name Request Cancel (0x01|0x001a) plen 6
bdaddr 00:16:CF:E1:C7:D7

Signed-off-by: Ville Tervo <[email protected]>
---
include/net/bluetooth/hci.h | 3 +++
include/net/bluetooth/hci_core.h | 2 +-
net/bluetooth/hci_core.c | 22 ++++++++++++++++------
net/bluetooth/hci_event.c | 6 ++++++
4 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 4bee030..918af32 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -119,6 +119,7 @@ enum {
#define HCI_PAIRING_TIMEOUT (60000) /* 60 seconds */
#define HCI_IDLE_TIMEOUT (6000) /* 6 seconds */
#define HCI_INIT_TIMEOUT (10000) /* 10 seconds */
+#define HCI_CMD_TIMEOUT (1000) /* 1 seconds */

/* HCI data types */
#define HCI_COMMAND_PKT 0x01
@@ -242,6 +243,8 @@ enum {
#define HCI_AT_GENERAL_BONDING_MITM 0x05

/* ----- HCI Commands ---- */
+#define HCI_OP_NOP 0x0000
+
#define HCI_OP_INQUIRY 0x0401
struct hci_cp_inquiry {
__u8 lap[3];
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 6163bff..51dd73b 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -128,7 +128,6 @@ struct hci_dev {
unsigned int acl_pkts;
unsigned int sco_pkts;

- unsigned long cmd_last_tx;
unsigned long acl_last_tx;
unsigned long sco_last_tx;

@@ -138,6 +137,7 @@ struct hci_dev {
struct work_struct power_off;
struct timer_list off_timer;

+ struct timer_list cmd_timer;
struct tasklet_struct cmd_task;
struct tasklet_struct rx_task;
struct tasklet_struct tx_task;
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 2f00322..069c2bc 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -41,6 +41,7 @@
#include <linux/interrupt.h>
#include <linux/notifier.h>
#include <linux/rfkill.h>
+#include <linux/timer.h>
#include <net/sock.h>

#include <asm/system.h>
@@ -611,6 +612,7 @@ static int hci_dev_do_close(struct hci_dev *hdev)

/* Drop last sent command */
if (hdev->sent_cmd) {
+ del_timer_sync(&hdev->cmd_timer);
kfree_skb(hdev->sent_cmd);
hdev->sent_cmd = NULL;
}
@@ -1054,6 +1056,16 @@ int hci_remove_link_key(struct hci_dev *hdev, bdaddr_t *bdaddr)
return 0;
}

+/* HCI command timer function */
+static void hci_cmd_timer(unsigned long arg)
+{
+ struct hci_dev *hdev = (void *) arg;
+
+ BT_ERR("%s command tx timeout", hdev->name);
+ atomic_set(&hdev->cmd_cnt, 1);
+ tasklet_schedule(&hdev->cmd_task);
+}
+
/* Register HCI device */
int hci_register_dev(struct hci_dev *hdev)
{
@@ -1100,6 +1112,8 @@ int hci_register_dev(struct hci_dev *hdev)
skb_queue_head_init(&hdev->cmd_q);
skb_queue_head_init(&hdev->raw_q);

+ setup_timer(&hdev->cmd_timer, hci_cmd_timer, (unsigned long) hdev);
+
for (i = 0; i < NUM_REASSEMBLY; i++)
hdev->reassembly[i] = NULL;

@@ -1936,11 +1950,6 @@ static void hci_cmd_task(unsigned long arg)

BT_DBG("%s cmd %d", hdev->name, atomic_read(&hdev->cmd_cnt));

- if (!atomic_read(&hdev->cmd_cnt) && time_after(jiffies, hdev->cmd_last_tx + HZ)) {
- BT_ERR("%s command tx timeout", hdev->name);
- atomic_set(&hdev->cmd_cnt, 1);
- }
-
/* Send queued commands */
if (atomic_read(&hdev->cmd_cnt)) {
skb = skb_dequeue(&hdev->cmd_q);
@@ -1953,7 +1962,8 @@ static void hci_cmd_task(unsigned long arg)
if (hdev->sent_cmd) {
atomic_dec(&hdev->cmd_cnt);
hci_send_frame(skb);
- hdev->cmd_last_tx = jiffies;
+ mod_timer(&hdev->cmd_timer,
+ jiffies + msecs_to_jiffies(HCI_CMD_TIMEOUT));
} else {
skb_queue_head(&hdev->cmd_q, skb);
tasklet_schedule(&hdev->cmd_task);
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index cee46cb..3836fd3 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -1672,6 +1672,9 @@ static inline void hci_cmd_complete_evt(struct hci_dev *hdev, struct sk_buff *sk
break;
}

+ if (ev->opcode != HCI_OP_NOP)
+ del_timer(&hdev->cmd_timer);
+
if (ev->ncmd) {
atomic_set(&hdev->cmd_cnt, 1);
if (!skb_queue_empty(&hdev->cmd_q))
@@ -1743,6 +1746,9 @@ static inline void hci_cmd_status_evt(struct hci_dev *hdev, struct sk_buff *skb)
break;
}

+ if (ev->opcode != HCI_OP_NOP)
+ del_timer(&hdev->cmd_timer);
+
if (ev->ncmd) {
atomic_set(&hdev->cmd_cnt, 1);
if (!skb_queue_empty(&hdev->cmd_q))
--
1.7.1



2011-02-14 14:40:03

by Gustavo Padovan

[permalink] [raw]
Subject: Re: [PATCH v2] Bluetooth: Use proper timer for hci command timout

Hi Ville,

* [email protected] <[email protected]> [2011-02-14 13:36:12 +0200]:

> From: Ville Tervo <[email protected]>
>
> Use proper timer instead of hci command flow control to timeout
> failed hci commands. Otherwise stack ends up sending commands
> when flow control is used to block new commands.
>
> 2010-09-01 18:29:41.592132 < HCI Command: Remote Name Request (0x01|0x0019) plen 10
> bdaddr 00:16:CF:E1:C7:D7 mode 2 clkoffset 0x0000
> 2010-09-01 18:29:41.592681 > HCI Event: Command Status (0x0f) plen 4
> Remote Name Request (0x01|0x0019) status 0x00 ncmd 0
> 2010-09-01 18:29:51.022033 < HCI Command: Remote Name Request Cancel (0x01|0x001a) plen 6
> bdaddr 00:16:CF:E1:C7:D7
>
> Signed-off-by: Ville Tervo <[email protected]>
> ---
> include/net/bluetooth/hci.h | 3 +++
> include/net/bluetooth/hci_core.h | 2 +-
> net/bluetooth/hci_core.c | 22 ++++++++++++++++------
> net/bluetooth/hci_event.c | 6 ++++++
> 4 files changed, 26 insertions(+), 7 deletions(-)

Patch has been applied. Thanks.

--
Gustavo F. Padovan
http://profusion.mobi