From 523ded71de0c5e66973335bf99a80edfda9f401b Mon Sep 17 00:00:00 2001 From: Alan Stern Date: Thu, 26 Apr 2007 00:12:04 -0700 Subject: device_schedule_callback() needs a module reference This patch (as896b) fixes an oversight in the design of device_schedule_callback(). It is necessary to acquire a reference to the module owning the callback routine, to prevent the module from being unloaded before the callback can run. Signed-off-by: Alan Stern Cc: Satyam Sharma Cc: Neil Brown Cc: Cornelia Huck Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'drivers/base/core.c') diff --git a/drivers/base/core.c b/drivers/base/core.c index f69305c7269..8aa090da1cd 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -480,9 +480,10 @@ void device_remove_bin_file(struct device *dev, struct bin_attribute *attr) EXPORT_SYMBOL_GPL(device_remove_bin_file); /** - * device_schedule_callback - helper to schedule a callback for a device + * device_schedule_callback_owner - helper to schedule a callback for a device * @dev: device. * @func: callback function to invoke later. + * @owner: module owning the callback routine * * Attribute methods must not unregister themselves or their parent device * (which would amount to the same thing). Attempts to do so will deadlock, @@ -493,20 +494,23 @@ EXPORT_SYMBOL_GPL(device_remove_bin_file); * argument in the workqueue's process context. @dev will be pinned until * @func returns. * + * This routine is usually called via the inline device_schedule_callback(), + * which automatically sets @owner to THIS_MODULE. + * * Returns 0 if the request was submitted, -ENOMEM if storage could not - * be allocated. + * be allocated, -ENODEV if a reference to @owner isn't available. * * NOTE: This routine won't work if CONFIG_SYSFS isn't set! It uses an * underlying sysfs routine (since it is intended for use by attribute * methods), and if sysfs isn't available you'll get nothing but -ENOSYS. */ -int device_schedule_callback(struct device *dev, - void (*func)(struct device *)) +int device_schedule_callback_owner(struct device *dev, + void (*func)(struct device *), struct module *owner) { return sysfs_schedule_callback(&dev->kobj, - (void (*)(void *)) func, dev); + (void (*)(void *)) func, dev, owner); } -EXPORT_SYMBOL_GPL(device_schedule_callback); +EXPORT_SYMBOL_GPL(device_schedule_callback_owner); static void klist_children_get(struct klist_node *n) { -- cgit v1.2.3