diff options
Diffstat (limited to 'drivers/input/input.c')
| -rw-r--r-- | drivers/input/input.c | 36 |
1 files changed, 15 insertions, 21 deletions
diff --git a/drivers/input/input.c b/drivers/input/input.c index 3070c7aa1237..2f2b020cd629 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -65,16 +65,16 @@ static int input_defuzz_abs_event(int value, int old_val, int fuzz) /* * Pass event through all open handles. This function is called with - * dev->event_lock held and interrupts disabled. Because of that we - * do not need to use rcu_read_lock() here although we are using RCU - * to access handle list. Note that because of that write-side uses - * synchronize_sched() instead of synchronize_ru(). + * dev->event_lock held and interrupts disabled. */ static void input_pass_event(struct input_dev *dev, unsigned int type, unsigned int code, int value) { - struct input_handle *handle = rcu_dereference(dev->grab); + struct input_handle *handle; + + rcu_read_lock(); + handle = rcu_dereference(dev->grab); if (handle) handle->handler->event(handle, type, code, value); else @@ -82,6 +82,7 @@ static void input_pass_event(struct input_dev *dev, if (handle->open) handle->handler->event(handle, type, code, value); + rcu_read_unlock(); } /* @@ -293,9 +294,11 @@ void input_inject_event(struct input_handle *handle, if (is_event_supported(type, dev->evbit, EV_MAX)) { spin_lock_irqsave(&dev->event_lock, flags); + rcu_read_lock(); grab = rcu_dereference(dev->grab); if (!grab || grab == handle) input_handle_event(dev, type, code, value); + rcu_read_unlock(); spin_unlock_irqrestore(&dev->event_lock, flags); } @@ -325,11 +328,7 @@ int input_grab_device(struct input_handle *handle) } rcu_assign_pointer(dev->grab, handle); - /* - * Not using synchronize_rcu() because read-side is protected - * by a spinlock with interrupts off instead of rcu_read_lock(). - */ - synchronize_sched(); + synchronize_rcu(); out: mutex_unlock(&dev->mutex); @@ -344,7 +343,7 @@ static void __input_release_device(struct input_handle *handle) if (dev->grab == handle) { rcu_assign_pointer(dev->grab, NULL); /* Make sure input_pass_event() notices that grab is gone */ - synchronize_sched(); + synchronize_rcu(); list_for_each_entry(handle, &dev->h_list, d_node) if (handle->open && handle->handler->start) @@ -404,7 +403,7 @@ int input_open_device(struct input_handle *handle) * Make sure we are not delivering any more events * through this handle */ - synchronize_sched(); + synchronize_rcu(); } } @@ -451,11 +450,11 @@ void input_close_device(struct input_handle *handle) if (!--handle->open) { /* - * synchronize_sched() makes sure that input_pass_event() + * synchronize_rcu() makes sure that input_pass_event() * completed and that no more input events are delivered * through this handle */ - synchronize_sched(); + synchronize_rcu(); } mutex_unlock(&dev->mutex); @@ -1477,12 +1476,7 @@ int input_register_handle(struct input_handle *handle) return error; list_add_tail_rcu(&handle->d_node, &dev->h_list); mutex_unlock(&dev->mutex); - /* - * We don't use synchronize_rcu() here because we rely - * on dev->event_lock to protect read-side critical - * section in input_pass_event(). - */ - synchronize_sched(); + synchronize_rcu(); /* * Since we are supposed to be called from ->connect() @@ -1521,7 +1515,7 @@ void input_unregister_handle(struct input_handle *handle) mutex_lock(&dev->mutex); list_del_rcu(&handle->d_node); mutex_unlock(&dev->mutex); - synchronize_sched(); + synchronize_rcu(); } EXPORT_SYMBOL(input_unregister_handle); |