fs/f2fs/f2fs.h

397 struct discard_cmd_control {  struct
398 	struct task_struct *f2fs_issue_discard;	/* discard thread */
399 	struct list_head entry_list;		/* 4KB discard entry list */
400 	struct list_head pend_list[MAX_PLIST_NUM];/* store pending entries */
401 	struct list_head wait_list;		/* store on-flushing entries */
402 	struct list_head fstrim_list;		/* in-flight discard from fstrim */
403 	wait_queue_head_t discard_wait_queue;	/* waiting queue for wake-up */
404 	struct mutex cmd_lock;
405 	unsigned int nr_discards;		/* # of discards in the list */
406 	unsigned int max_discards;		/* max. discards to be issued */
407 	unsigned int max_discard_request;	/* max. discard request per round */
408 	unsigned int min_discard_issue_time;	/* min. interval between discard issue */
409 	unsigned int mid_discard_issue_time;	/* mid. interval between discard issue */
410 	unsigned int max_discard_issue_time;	/* max. interval between discard issue */
411 	unsigned int discard_io_aware_gran; /* minimum discard granularity not be aware of I/O */
412 	unsigned int discard_urgent_util;	/* utilization which issue discard proactively */
413 	unsigned int discard_granularity;	/* discard granularity */
414 	unsigned int max_ordered_discard;	/* maximum discard granularity issued by lba order */
415 	unsigned int discard_io_aware;		/* io_aware policy */
416 	unsigned int undiscard_blks;		/* # of undiscard blocks */
417 	unsigned int next_pos;			/* next discard position */
418 	atomic_t issued_discard;		/* # of issued discard */
419 	atomic_t queued_discard;		/* # of queued discard */
420 	atomic_t discard_cmd_cnt;		/* # of cached cmd count */
421 	struct rb_root_cached root;		/* root of discard rb-tree */
422 	bool rbtree_check;			/* config for consistence check */
423 	bool discard_wake;			/* to wake up discard thread */