&f2fs_seq_segment_info_fops, sb);if(test_opt(sbi, DISCARD)) {structrequest_queue*q=bdev_get_queue(sb->s_bdev);if(!blk_queue_discard(q)) f2fs_msg(sb, KERN_WARNING,"mounting with \"discard\" option, but ""the device does not support discard"); } sbi->s_kobj.kset = f2fs_kset...