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-rw-r--r--drivers/net/usb/hso.c110
1 files changed, 87 insertions, 23 deletions
diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c
index 2c172435495..cc37a2e6717 100644
--- a/drivers/net/usb/hso.c
+++ b/drivers/net/usb/hso.c
@@ -230,6 +230,11 @@ struct hso_serial {
struct work_struct retry_unthrottle_workqueue;
};
+struct hso_mutex_t {
+ struct mutex mutex;
+ u8 allocated;
+};
+
struct hso_device {
union {
struct hso_serial *dev_serial;
@@ -248,7 +253,7 @@ struct hso_device {
struct device *dev;
struct kref ref;
- struct mutex mutex;
+ struct hso_mutex_t *mutex;
};
/* Type of interface */
@@ -364,6 +369,13 @@ static struct hso_device *network_table[HSO_MAX_NET_DEVICES];
static spinlock_t serial_table_lock;
static struct ktermios *hso_serial_termios[HSO_SERIAL_TTY_MINORS];
static struct ktermios *hso_serial_termios_locked[HSO_SERIAL_TTY_MINORS];
+/* hso_mutex_table has to be declared statically as hso_device
+ * is freed in hso_serial_open & hso_serial_close while
+ * the mutex is still in use.
+ */
+#define HSO_NUM_MUTEXES (HSO_SERIAL_TTY_MINORS+HSO_MAX_NET_DEVICES)
+static struct hso_mutex_t hso_mutex_table[HSO_NUM_MUTEXES];
+static spinlock_t hso_mutex_lock;
static const s32 default_port_spec[] = {
HSO_INTF_MUX | HSO_PORT_NETWORK,
@@ -604,6 +616,34 @@ static void set_serial_by_index(unsigned index, struct hso_serial *serial)
spin_unlock_irqrestore(&serial_table_lock, flags);
}
+
+static struct hso_mutex_t *hso_get_free_mutex(void)
+{
+ int index;
+ struct hso_mutex_t *curr_hso_mutex;
+
+ spin_lock(&hso_mutex_lock);
+ for (index = 0; index < HSO_NUM_MUTEXES; index++) {
+ curr_hso_mutex = &hso_mutex_table[index];
+ if (!curr_hso_mutex->allocated) {
+ curr_hso_mutex->allocated = 1;
+ spin_unlock(&hso_mutex_lock);
+ return curr_hso_mutex;
+ }
+ }
+ printk(KERN_ERR "BUG %s: no free hso_mutexs devices in table\n"
+ , __func__);
+ spin_unlock(&hso_mutex_lock);
+ return NULL;
+}
+
+static void hso_free_mutex(struct hso_mutex_t *mutex)
+{
+ spin_lock(&hso_mutex_lock);
+ mutex->allocated = 0;
+ spin_unlock(&hso_mutex_lock);
+}
+
/* log a meaningful explanation of an USB status */
static void log_usb_status(int status, const char *function)
{
@@ -1225,7 +1265,9 @@ void hso_unthrottle_workfunc(struct work_struct *work)
static int hso_serial_open(struct tty_struct *tty, struct file *filp)
{
struct hso_serial *serial = get_serial_by_index(tty->index);
- int result;
+ int result1 = 0, result2 = 0;
+ struct mutex *hso_mutex = NULL;
+ int refcnt = 1;
/* sanity check */
if (serial == NULL || serial->magic != HSO_SERIAL_MAGIC) {
@@ -1234,14 +1276,15 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp)
return -ENODEV;
}
- mutex_lock(&serial->parent->mutex);
+ hso_mutex = &serial->parent->mutex->mutex;
+ mutex_lock(hso_mutex);
/* check for port already opened, if not set the termios */
/* The serial->open count needs to be here as hso_serial_close
* will be called even if hso_serial_open returns -ENODEV.
*/
serial->open_count++;
- result = usb_autopm_get_interface(serial->parent->interface);
- if (result < 0)
+ result1 = usb_autopm_get_interface(serial->parent->interface);
+ if (result1 < 0)
goto err_out;
D1("Opening %d", serial->minor);
@@ -1261,11 +1304,10 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp)
(unsigned long)serial);
INIT_WORK(&serial->retry_unthrottle_workqueue,
hso_unthrottle_workfunc);
- result = hso_start_serial_device(serial->parent, GFP_KERNEL);
- if (result) {
+ result2 = hso_start_serial_device(serial->parent, GFP_KERNEL);
+ if (result2) {
hso_stop_serial_device(serial->parent);
serial->open_count--;
- kref_put(&serial->parent->ref, hso_serial_ref_free);
}
} else {
D1("Port was already open");
@@ -1274,11 +1316,16 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp)
usb_autopm_put_interface(serial->parent->interface);
/* done */
- if (result)
+ if (result1)
hso_serial_tiocmset(tty, NULL, TIOCM_RTS | TIOCM_DTR, 0);
err_out:
- mutex_unlock(&serial->parent->mutex);
- return result;
+ if (result2)
+ refcnt = kref_put(&serial->parent->ref, hso_serial_ref_free);
+ mutex_unlock(hso_mutex);
+ if (refcnt == 0)
+ hso_free_mutex(container_of(hso_mutex,
+ struct hso_mutex_t, mutex));
+ return result1 == 0 ? result2 : result1;
}
/* close the requested serial port */
@@ -1286,6 +1333,8 @@ static void hso_serial_close(struct tty_struct *tty, struct file *filp)
{
struct hso_serial *serial = tty->driver_data;
u8 usb_gone;
+ struct mutex *hso_mutex;
+ int refcnt;
D1("Closing serial port");
if (serial == NULL || serial->magic != HSO_SERIAL_MAGIC) {
@@ -1293,8 +1342,9 @@ static void hso_serial_close(struct tty_struct *tty, struct file *filp)
return;
}
- mutex_lock(&serial->parent->mutex);
usb_gone = serial->parent->usb_gone;
+ hso_mutex = &serial->parent->mutex->mutex;
+ mutex_lock(hso_mutex);
if (!usb_gone)
usb_autopm_get_interface(serial->parent->interface);
@@ -1302,7 +1352,6 @@ static void hso_serial_close(struct tty_struct *tty, struct file *filp)
/* reset the rts and dtr */
/* do the actual close */
serial->open_count--;
- kref_put(&serial->parent->ref, hso_serial_ref_free);
if (serial->open_count <= 0) {
serial->open_count = 0;
if (serial->tty) {
@@ -1317,8 +1366,11 @@ static void hso_serial_close(struct tty_struct *tty, struct file *filp)
if (!usb_gone)
usb_autopm_put_interface(serial->parent->interface);
-
- mutex_unlock(&serial->parent->mutex);
+ refcnt = kref_put(&serial->parent->ref, hso_serial_ref_free);
+ mutex_unlock(hso_mutex);
+ if (refcnt == 0)
+ hso_free_mutex(container_of(hso_mutex,
+ struct hso_mutex_t, mutex));
}
/* close the requested serial port */
@@ -2084,8 +2136,12 @@ static struct hso_device *hso_create_device(struct usb_interface *intf,
hso_dev->usb = interface_to_usbdev(intf);
hso_dev->interface = intf;
kref_init(&hso_dev->ref);
- mutex_init(&hso_dev->mutex);
-
+ hso_dev->mutex = hso_get_free_mutex();
+ if (!hso_dev->mutex) {
+ kfree(hso_dev);
+ return NULL;
+ }
+ mutex_init(&hso_dev->mutex->mutex);
INIT_WORK(&hso_dev->async_get_intf, async_get_intf);
INIT_WORK(&hso_dev->async_put_intf, async_put_intf);
@@ -2131,7 +2187,7 @@ static void hso_free_net_device(struct hso_device *hso_dev)
unregister_netdev(hso_net->net);
free_netdev(hso_net->net);
}
-
+ hso_free_mutex(hso_dev->mutex);
hso_free_device(hso_dev);
}
@@ -2180,14 +2236,14 @@ static int hso_radio_toggle(void *data, enum rfkill_state state)
int enabled = (state == RFKILL_STATE_ON);
int rv;
- mutex_lock(&hso_dev->mutex);
+ mutex_lock(&hso_dev->mutex->mutex);
if (hso_dev->usb_gone)
rv = 0;
else
rv = usb_control_msg(hso_dev->usb, usb_rcvctrlpipe(hso_dev->usb, 0),
enabled ? 0x82 : 0x81, 0x40, 0, 0, NULL, 0,
USB_CTRL_SET_TIMEOUT);
- mutex_unlock(&hso_dev->mutex);
+ mutex_unlock(&hso_dev->mutex->mutex);
return rv;
}
@@ -2795,6 +2851,8 @@ static void hso_free_interface(struct usb_interface *interface)
{
struct hso_serial *hso_dev;
int i;
+ struct mutex *hso_mutex = NULL;
+ int refcnt = 1;
for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++) {
if (serial_table[i]
@@ -2802,10 +2860,12 @@ static void hso_free_interface(struct usb_interface *interface)
hso_dev = dev2ser(serial_table[i]);
if (hso_dev->tty)
tty_hangup(hso_dev->tty);
- mutex_lock(&hso_dev->parent->mutex);
+ hso_mutex = &hso_dev->parent->mutex->mutex;
+ mutex_lock(hso_mutex);
hso_dev->parent->usb_gone = 1;
- mutex_unlock(&hso_dev->parent->mutex);
- kref_put(&serial_table[i]->ref, hso_serial_ref_free);
+ refcnt = kref_put(&serial_table[i]->ref,
+ hso_serial_ref_free);
+ mutex_unlock(hso_mutex);
}
}
@@ -2824,6 +2884,9 @@ static void hso_free_interface(struct usb_interface *interface)
hso_free_net_device(network_table[i]);
}
}
+ if (refcnt == 0)
+ hso_free_mutex(container_of(hso_mutex,
+ struct hso_mutex_t, mutex));
}
/* Helper functions */
@@ -2922,6 +2985,7 @@ static int __init hso_init(void)
/* Initialise the serial table semaphore and table */
spin_lock_init(&serial_table_lock);
+ spin_lock_init(&hso_mutex_lock);
for (i = 0; i < HSO_SERIAL_TTY_MINORS; i++)
serial_table[i] = NULL;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 09:27:50 +0000