linux-master/fs/fcntl.c

874 int fasync_remove_entry(struct file *filp, struct fasync_struct **fapp)
881 	for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
922 struct fasync_struct *fasync_insert_entry(int fd, struct file *filp, struct fasync_struct **fapp, struct fasync_struct *new)
928 	for (fp = fapp; (fa = *fp) != NULL; fp = &fa->fa_next) {
942 	new->fa_next = *fapp;
943 	rcu_assign_pointer(*fapp, new);
956 static int fasync_add_entry(int fd, struct file *filp, struct fasync_struct **fapp)
971 	if (fasync_insert_entry(fd, filp, fapp, new)) {
985 int fasync_helper(int fd, struct file * filp, int on, struct fasync_struct **fapp)
988 		return fasync_remove_entry(filp, fapp);
989 	return fasync_add_entry(fd, filp, fapp);