From ab153d84d9609b4e6f53632a6f14b882e866cb47 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Tue, 25 Nov 2008 03:52:46 -0800 Subject: [PATCH] Revert "hso: Fix free of mutexes still in use." This reverts commit 52429eb216385fdc6969c0112ba8b46cffefaaef. On request from Alan Cox. Signed-off-by: David S. Miller --- drivers/net/usb/hso.c | 110 +++++++++--------------------------------- 1 file changed, 23 insertions(+), 87 deletions(-) diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c index af62f58ffcb..39df44f99d6 100644 --- a/drivers/net/usb/hso.c +++ b/drivers/net/usb/hso.c @@ -230,11 +230,6 @@ 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; @@ -253,7 +248,7 @@ struct hso_device { struct device *dev; struct kref ref; - struct hso_mutex_t *mutex; + struct mutex mutex; }; /* Type of interface */ @@ -369,13 +364,6 @@ 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, @@ -616,34 +604,6 @@ 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) { @@ -1265,9 +1225,7 @@ 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 result1 = 0, result2 = 0; - struct mutex *hso_mutex = NULL; - int refcnt = 1; + int result; /* sanity check */ if (serial == NULL || serial->magic != HSO_SERIAL_MAGIC) { @@ -1276,15 +1234,14 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp) return -ENODEV; } - hso_mutex = &serial->parent->mutex->mutex; - mutex_lock(hso_mutex); + mutex_lock(&serial->parent->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++; - result1 = usb_autopm_get_interface(serial->parent->interface); - if (result1 < 0) + result = usb_autopm_get_interface(serial->parent->interface); + if (result < 0) goto err_out; D1("Opening %d", serial->minor); @@ -1304,10 +1261,11 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp) (unsigned long)serial); INIT_WORK(&serial->retry_unthrottle_workqueue, hso_unthrottle_workfunc); - result2 = hso_start_serial_device(serial->parent, GFP_KERNEL); - if (result2) { + result = hso_start_serial_device(serial->parent, GFP_KERNEL); + if (result) { hso_stop_serial_device(serial->parent); serial->open_count--; + kref_put(&serial->parent->ref, hso_serial_ref_free); } } else { D1("Port was already open"); @@ -1316,16 +1274,11 @@ static int hso_serial_open(struct tty_struct *tty, struct file *filp) usb_autopm_put_interface(serial->parent->interface); /* done */ - if (result1) + if (result) hso_serial_tiocmset(tty, NULL, TIOCM_RTS | TIOCM_DTR, 0); err_out: - 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; + mutex_unlock(&serial->parent->mutex); + return result; } /* close the requested serial port */ @@ -1333,8 +1286,6 @@ 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) { @@ -1342,9 +1293,8 @@ 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); @@ -1352,6 +1302,7 @@ 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) { @@ -1366,11 +1317,8 @@ static void hso_serial_close(struct tty_struct *tty, struct file *filp) if (!usb_gone) usb_autopm_put_interface(serial->parent->interface); - 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)); + + mutex_unlock(&serial->parent->mutex); } /* close the requested serial port */ @@ -2136,12 +2084,8 @@ 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); - hso_dev->mutex = hso_get_free_mutex(); - if (!hso_dev->mutex) { - kfree(hso_dev); - return NULL; - } - mutex_init(&hso_dev->mutex->mutex); + mutex_init(&hso_dev->mutex); + INIT_WORK(&hso_dev->async_get_intf, async_get_intf); INIT_WORK(&hso_dev->async_put_intf, async_put_intf); @@ -2187,7 +2131,7 @@ 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); } @@ -2236,14 +2180,14 @@ 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); + mutex_lock(&hso_dev->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); + mutex_unlock(&hso_dev->mutex); return rv; } @@ -2851,8 +2795,6 @@ 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] @@ -2860,12 +2802,10 @@ static void hso_free_interface(struct usb_interface *interface) hso_dev = dev2ser(serial_table[i]); if (hso_dev->tty) tty_hangup(hso_dev->tty); - hso_mutex = &hso_dev->parent->mutex->mutex; - mutex_lock(hso_mutex); + mutex_lock(&hso_dev->parent->mutex); hso_dev->parent->usb_gone = 1; - refcnt = kref_put(&serial_table[i]->ref, - hso_serial_ref_free); - mutex_unlock(hso_mutex); + mutex_unlock(&hso_dev->parent->mutex); + kref_put(&serial_table[i]->ref, hso_serial_ref_free); } } @@ -2884,9 +2824,6 @@ 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 */ @@ -2986,7 +2923,6 @@ 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; -- 2.41.0