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USB: kill BKL in skeleton driver

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Iet's kill BKL where we can. This is relative to the last patch to the
skeleton driver.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Oliver Neukum
2007-03-01 23:07:32 +01:00
committed by Greg Kroah-Hartman
parent ba35e02bdc
commit 5d9b89b33f
1 changed files with 10 additions and 2 deletions
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12
drivers/usb/usb-skeleton.c
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@@ -34,6 +34,9 @@ static struct usb_device_id skel_table [] = {
}; };
MODULE_DEVICE_TABLE(usb, skel_table); MODULE_DEVICE_TABLE(usb, skel_table);
/* to prevent a race between open and disconnect */
static DEFINE_MUTEX(skel_open_lock);
/* Get a minor range for your devices from the usb maintainer */ /* Get a minor range for your devices from the usb maintainer */
#define USB_SKEL_MINOR_BASE 192 #define USB_SKEL_MINOR_BASE 192
@@ -80,8 +83,10 @@ static int skel_open(struct inode *inode, struct file *file)
subminor = iminor(inode); subminor = iminor(inode);
mutex_lock(&skel_open_lock);
interface = usb_find_interface(&skel_driver, subminor); interface = usb_find_interface(&skel_driver, subminor);
if (!interface) { if (!interface) {
mutex_unlock(&skel_open_lock);
err ("%s - error, can't find device for minor %d", err ("%s - error, can't find device for minor %d",
__FUNCTION__, subminor); __FUNCTION__, subminor);
retval = -ENODEV; retval = -ENODEV;
@@ -90,12 +95,15 @@ static int skel_open(struct inode *inode, struct file *file)
dev = usb_get_intfdata(interface); dev = usb_get_intfdata(interface);
if (!dev) { if (!dev) {
mutex_unlock(&skel_open_lock);
retval = -ENODEV; retval = -ENODEV;
goto exit; goto exit;
} }
/* increment our usage count for the device */ /* increment our usage count for the device */
kref_get(&dev->kref); kref_get(&dev->kref);
/* now we can drop the lock */
mutex_unlock(&skel_open_lock);
/* prevent the device from being autosuspended */ /* prevent the device from being autosuspended */
retval = usb_autopm_get_interface(interface); retval = usb_autopm_get_interface(interface);
@@ -361,14 +369,14 @@ static void skel_disconnect(struct usb_interface *interface)
int minor = interface->minor; int minor = interface->minor;
/* prevent skel_open() from racing skel_disconnect() */ /* prevent skel_open() from racing skel_disconnect() */
lock_kernel(); mutex_lock(&skel_open_lock);
dev = usb_get_intfdata(interface); dev = usb_get_intfdata(interface);
usb_set_intfdata(interface, NULL); usb_set_intfdata(interface, NULL);
/* give back our minor */ /* give back our minor */
usb_deregister_dev(interface, &skel_class); usb_deregister_dev(interface, &skel_class);
unlock_kernel(); mutex_unlock(&skel_open_lock);
/* prevent more I/O from starting */ /* prevent more I/O from starting */
mutex_lock(&dev->io_mutex); mutex_lock(&dev->io_mutex);