Linux Kernel input evdev

struct evdev { int open; struct input_handle handle; wait_queue_head_t wait; struct evdev_client __rcu *grab; struct list_head client_list; spinlock_t client_lock; /* protects client_list */ struct mutex mutex; struct device dev; struct cdev cdev; bool exist; }; struct evdev_client { unsigned int head; unsigned int tail; unsigned int packet_head; /* [future] position of the first element of next packet */ spinlock_t buffer_lock; /* protects access to buffer, head and tail */ struct fasync_struct *fasync; struct evdev *evdev; struct list_head node; unsigned int clk_type; bool revoked; unsigned long *evmasks[EV_CNT]; unsigned int bufsize; struct input_event buffer[]; };