forked from luck/tmp_suning_uos_patched
w1: remove race with sysfs file creation
W1 slave sysfs files are created _after_ userspace is notified that the device has been added to the system. Fix that race by moving the creation/remove of the files to the bus notifier that is there for doing this type of thing. Acked-by: Evgeniy Polyakov <zbr@ioremap.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
3e1026b3fa
commit
47eba33a09
111
drivers/w1/w1.c
111
drivers/w1/w1.c
|
@ -587,6 +587,73 @@ static int w1_uevent(struct device *dev, struct kobj_uevent_env *env)
|
|||
return err;
|
||||
}
|
||||
|
||||
/*
|
||||
* Handle sysfs file creation and removal here, before userspace is told that
|
||||
* the device is added / removed from the system
|
||||
*/
|
||||
static int w1_bus_notify(struct notifier_block *nb, unsigned long action,
|
||||
void *data)
|
||||
{
|
||||
struct device *dev = data;
|
||||
struct w1_slave *sl;
|
||||
int err;
|
||||
|
||||
/*
|
||||
* Only care about slave devices at the moment. Yes, we should use a
|
||||
* separate "type" for this, but for now, look at the release function
|
||||
* to know which type it is...
|
||||
*/
|
||||
if (dev->release != w1_slave_release)
|
||||
return 0;
|
||||
|
||||
sl = dev_to_w1_slave(dev);
|
||||
|
||||
switch (action) {
|
||||
case BUS_NOTIFY_ADD_DEVICE:
|
||||
/* Create our sysfs files before userspace is told about it */
|
||||
/* Create "name" entry */
|
||||
err = device_create_file(&sl->dev, &w1_slave_attr_name);
|
||||
if (err < 0) {
|
||||
dev_err(&sl->dev,
|
||||
"sysfs file creation for [%s] failed. err=%d\n",
|
||||
dev_name(&sl->dev), err);
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Create "id" entry */
|
||||
err = device_create_file(&sl->dev, &w1_slave_attr_id);
|
||||
if (err < 0) {
|
||||
dev_err(&sl->dev,
|
||||
"sysfs file creation for [%s] failed. err=%d\n",
|
||||
dev_name(&sl->dev), err);
|
||||
return err;
|
||||
}
|
||||
|
||||
/* if the family driver needs to initialize something... */
|
||||
if (sl->family->fops && sl->family->fops->add_slave &&
|
||||
((err = sl->family->fops->add_slave(sl)) < 0)) {
|
||||
dev_err(&sl->dev,
|
||||
"sysfs file creation for [%s] failed. err=%d\n",
|
||||
dev_name(&sl->dev), err);
|
||||
return err;
|
||||
}
|
||||
|
||||
break;
|
||||
case BUS_NOTIFY_DEL_DEVICE:
|
||||
/* Remove our sysfs files */
|
||||
if (sl->family->fops && sl->family->fops->remove_slave)
|
||||
sl->family->fops->remove_slave(sl);
|
||||
device_remove_file(&sl->dev, &w1_slave_attr_id);
|
||||
device_remove_file(&sl->dev, &w1_slave_attr_name);
|
||||
break;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct notifier_block w1_bus_nb = {
|
||||
.notifier_call = w1_bus_notify,
|
||||
};
|
||||
|
||||
static int __w1_attach_slave_device(struct w1_slave *sl)
|
||||
{
|
||||
int err;
|
||||
|
@ -615,44 +682,13 @@ static int __w1_attach_slave_device(struct w1_slave *sl)
|
|||
return err;
|
||||
}
|
||||
|
||||
/* Create "name" entry */
|
||||
err = device_create_file(&sl->dev, &w1_slave_attr_name);
|
||||
if (err < 0) {
|
||||
dev_err(&sl->dev,
|
||||
"sysfs file creation for [%s] failed. err=%d\n",
|
||||
dev_name(&sl->dev), err);
|
||||
goto out_unreg;
|
||||
}
|
||||
|
||||
/* Create "id" entry */
|
||||
err = device_create_file(&sl->dev, &w1_slave_attr_id);
|
||||
if (err < 0) {
|
||||
dev_err(&sl->dev,
|
||||
"sysfs file creation for [%s] failed. err=%d\n",
|
||||
dev_name(&sl->dev), err);
|
||||
goto out_rem1;
|
||||
}
|
||||
|
||||
/* if the family driver needs to initialize something... */
|
||||
if (sl->family->fops && sl->family->fops->add_slave &&
|
||||
((err = sl->family->fops->add_slave(sl)) < 0)) {
|
||||
dev_err(&sl->dev,
|
||||
"sysfs file creation for [%s] failed. err=%d\n",
|
||||
dev_name(&sl->dev), err);
|
||||
goto out_rem2;
|
||||
}
|
||||
dev_set_uevent_suppress(&sl->dev, false);
|
||||
kobject_uevent(&sl->dev.kobj, KOBJ_ADD);
|
||||
|
||||
list_add_tail(&sl->w1_slave_entry, &sl->master->slist);
|
||||
|
||||
return 0;
|
||||
|
||||
out_rem2:
|
||||
device_remove_file(&sl->dev, &w1_slave_attr_id);
|
||||
out_rem1:
|
||||
device_remove_file(&sl->dev, &w1_slave_attr_name);
|
||||
out_unreg:
|
||||
device_unregister(&sl->dev);
|
||||
return err;
|
||||
}
|
||||
|
||||
static int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn)
|
||||
|
@ -723,16 +759,11 @@ void w1_slave_detach(struct w1_slave *sl)
|
|||
|
||||
list_del(&sl->w1_slave_entry);
|
||||
|
||||
if (sl->family->fops && sl->family->fops->remove_slave)
|
||||
sl->family->fops->remove_slave(sl);
|
||||
|
||||
memset(&msg, 0, sizeof(msg));
|
||||
memcpy(msg.id.id, &sl->reg_num, sizeof(msg.id));
|
||||
msg.type = W1_SLAVE_REMOVE;
|
||||
w1_netlink_send(sl->master, &msg);
|
||||
|
||||
device_remove_file(&sl->dev, &w1_slave_attr_id);
|
||||
device_remove_file(&sl->dev, &w1_slave_attr_name);
|
||||
device_unregister(&sl->dev);
|
||||
|
||||
wait_for_completion(&sl->released);
|
||||
|
@ -1017,6 +1048,10 @@ static int __init w1_init(void)
|
|||
goto err_out_exit_init;
|
||||
}
|
||||
|
||||
retval = bus_register_notifier(&w1_bus_type, &w1_bus_nb);
|
||||
if (retval)
|
||||
goto err_out_bus_unregister;
|
||||
|
||||
retval = driver_register(&w1_master_driver);
|
||||
if (retval) {
|
||||
printk(KERN_ERR
|
||||
|
|
Loading…
Reference in New Issue
Block a user