The preferred method of initializing structures is to use designated initialisers, as defined by ISO C99, eg:

static struct block_device_operations opt_fops = {
        .open               = opt_open,
        .release            = opt_release,
        .ioctl              = opt_ioctl,
        .check_media_change = opt_media_change,
};
   

This makes it easy to grep for, and makes it clear which structure fields are set. You should do this because it looks cool.