[mirror_ubuntu-artful-kernel.git] / include / linux / elevator.h

#ifndef _LINUX_ELEVATOR_H
#define _LINUX_ELEVATOR_H

#include <linux/percpu.h>
#include <linux/hashtable.h>

#ifdef CONFIG_BLOCK

struct io_cq;
struct elevator_type;
#ifdef CONFIG_BLK_DEBUG_FS
struct blk_mq_debugfs_attr;
#endif

/*
 * Return values from elevator merger
 */
enum elv_merge {
	ELEVATOR_NO_MERGE	= 0,
	ELEVATOR_FRONT_MERGE	= 1,
	ELEVATOR_BACK_MERGE	= 2,
	ELEVATOR_DISCARD_MERGE	= 3,
};

typedef enum elv_merge (elevator_merge_fn) (struct request_queue *, struct request **,
				 struct bio *);

typedef void (elevator_merge_req_fn) (struct request_queue *, struct request *, struct request *);

typedef void (elevator_merged_fn) (struct request_queue *, struct request *, enum elv_merge);

typedef int (elevator_allow_bio_merge_fn) (struct request_queue *,
					   struct request *, struct bio *);

typedef int (elevator_allow_rq_merge_fn) (struct request_queue *,
					  struct request *, struct request *);

typedef void (elevator_bio_merged_fn) (struct request_queue *,
						struct request *, struct bio *);

typedef int (elevator_dispatch_fn) (struct request_queue *, int);

typedef void (elevator_add_req_fn) (struct request_queue *, struct request *);
typedef struct request *(elevator_request_list_fn) (struct request_queue *, struct request *);
typedef void (elevator_completed_req_fn) (struct request_queue *, struct request *);
typedef int (elevator_may_queue_fn) (struct request_queue *, unsigned int);

typedef void (elevator_init_icq_fn) (struct io_cq *);
typedef void (elevator_exit_icq_fn) (struct io_cq *);
typedef int (elevator_set_req_fn) (struct request_queue *, struct request *,
				   struct bio *, gfp_t);
typedef void (elevator_put_req_fn) (struct request *);
typedef void (elevator_activate_req_fn) (struct request_queue *, struct request *);
typedef void (elevator_deactivate_req_fn) (struct request_queue *, struct request *);

typedef int (elevator_init_fn) (struct request_queue *,
				struct elevator_type *e);
typedef void (elevator_exit_fn) (struct elevator_queue *);
typedef void (elevator_registered_fn) (struct request_queue *);

struct elevator_ops
{
	elevator_merge_fn *elevator_merge_fn;
	elevator_merged_fn *elevator_merged_fn;
	elevator_merge_req_fn *elevator_merge_req_fn;
	elevator_allow_bio_merge_fn *elevator_allow_bio_merge_fn;
	elevator_allow_rq_merge_fn *elevator_allow_rq_merge_fn;
	elevator_bio_merged_fn *elevator_bio_merged_fn;

	elevator_dispatch_fn *elevator_dispatch_fn;
	elevator_add_req_fn *elevator_add_req_fn;
	elevator_activate_req_fn *elevator_activate_req_fn;
	elevator_deactivate_req_fn *elevator_deactivate_req_fn;

	elevator_completed_req_fn *elevator_completed_req_fn;

	elevator_request_list_fn *elevator_former_req_fn;
	elevator_request_list_fn *elevator_latter_req_fn;

	elevator_init_icq_fn *elevator_init_icq_fn;	/* see iocontext.h */
	elevator_exit_icq_fn *elevator_exit_icq_fn;	/* ditto */

	elevator_set_req_fn *elevator_set_req_fn;
	elevator_put_req_fn *elevator_put_req_fn;

	elevator_may_queue_fn *elevator_may_queue_fn;

	elevator_init_fn *elevator_init_fn;
	elevator_exit_fn *elevator_exit_fn;
	elevator_registered_fn *elevator_registered_fn;
};

struct blk_mq_alloc_data;
struct blk_mq_hw_ctx;

struct elevator_mq_ops {
	int (*init_sched)(struct request_queue *, struct elevator_type *);
	void (*exit_sched)(struct elevator_queue *);
	int (*init_hctx)(struct blk_mq_hw_ctx *, unsigned int);
	void (*exit_hctx)(struct blk_mq_hw_ctx *, unsigned int);

	bool (*allow_merge)(struct request_queue *, struct request *, struct bio *);
	bool (*bio_merge)(struct blk_mq_hw_ctx *, struct bio *);
	int (*request_merge)(struct request_queue *q, struct request **, struct bio *);
	void (*request_merged)(struct request_queue *, struct request *, enum elv_merge);
	void (*requests_merged)(struct request_queue *, struct request *, struct request *);
	void (*limit_depth)(unsigned int, struct blk_mq_alloc_data *);
	void (*prepare_request)(struct request *, struct bio *bio);
	void (*finish_request)(struct request *);
	void (*insert_requests)(struct blk_mq_hw_ctx *, struct list_head *, bool);
	struct request *(*dispatch_request)(struct blk_mq_hw_ctx *);
	bool (*has_work)(struct blk_mq_hw_ctx *);
	void (*completed_request)(struct request *);
	void (*started_request)(struct request *);
	void (*requeue_request)(struct request *);
	struct request *(*former_request)(struct request_queue *, struct request *);
	struct request *(*next_request)(struct request_queue *, struct request *);
	void (*init_icq)(struct io_cq *);
	void (*exit_icq)(struct io_cq *);
};

#define ELV_NAME_MAX	(16)

struct elv_fs_entry {
	struct attribute attr;
	ssize_t (*show)(struct elevator_queue *, char *);
	ssize_t (*store)(struct elevator_queue *, const char *, size_t);
};

/*
 * identifies an elevator type, such as AS or deadline
 */
struct elevator_type
{
	/* managed by elevator core */
	struct kmem_cache *icq_cache;

	/* fields provided by elevator implementation */
	union {
		struct elevator_ops sq;
		struct elevator_mq_ops mq;
	} ops;
	size_t icq_size;	/* see iocontext.h */
	size_t icq_align;	/* ditto */
	struct elv_fs_entry *elevator_attrs;
	char elevator_name[ELV_NAME_MAX];
	struct module *elevator_owner;
	bool uses_mq;
#ifdef CONFIG_BLK_DEBUG_FS
	const struct blk_mq_debugfs_attr *queue_debugfs_attrs;
	const struct blk_mq_debugfs_attr *hctx_debugfs_attrs;
#endif

	/* managed by elevator core */
	char icq_cache_name[ELV_NAME_MAX + 6];	/* elvname + "_io_cq" */
	struct list_head list;
};

#define ELV_HASH_BITS 6

void elv_rqhash_del(struct request_queue *q, struct request *rq);
void elv_rqhash_add(struct request_queue *q, struct request *rq);
void elv_rqhash_reposition(struct request_queue *q, struct request *rq);
struct request *elv_rqhash_find(struct request_queue *q, sector_t offset);

/*
 * each queue has an elevator_queue associated with it
 */
struct elevator_queue
{
	struct elevator_type *type;
	void *elevator_data;
	struct kobject kobj;
	struct mutex sysfs_lock;
	unsigned int registered:1;
	unsigned int uses_mq:1;
	DECLARE_HASHTABLE(hash, ELV_HASH_BITS);
};

/*
 * block elevator interface
 */
extern void elv_dispatch_sort(struct request_queue *, struct request *);
extern void elv_dispatch_add_tail(struct request_queue *, struct request *);
extern void elv_add_request(struct request_queue *, struct request *, int);
extern void __elv_add_request(struct request_queue *, struct request *, int);
extern enum elv_merge elv_merge(struct request_queue *, struct request **,
		struct bio *);
extern void elv_merge_requests(struct request_queue *, struct request *,
			       struct request *);
extern void elv_merged_request(struct request_queue *, struct request *,
		enum elv_merge);
extern void elv_bio_merged(struct request_queue *q, struct request *,
				struct bio *);
extern bool elv_attempt_insert_merge(struct request_queue *, struct request *);
extern void elv_requeue_request(struct request_queue *, struct request *);
extern struct request *elv_former_request(struct request_queue *, struct request *);
extern struct request *elv_latter_request(struct request_queue *, struct request *);
extern int elv_register_queue(struct request_queue *q);
extern void elv_unregister_queue(struct request_queue *q);
extern int elv_may_queue(struct request_queue *, unsigned int);
extern void elv_completed_request(struct request_queue *, struct request *);
extern int elv_set_request(struct request_queue *q, struct request *rq,
			   struct bio *bio, gfp_t gfp_mask);
extern void elv_put_request(struct request_queue *, struct request *);
extern void elv_drain_elevator(struct request_queue *);

/*
 * io scheduler registration
 */
extern void __init load_default_elevator_module(void);
extern int elv_register(struct elevator_type *);
extern void elv_unregister(struct elevator_type *);

/*
 * io scheduler sysfs switching
 */
extern ssize_t elv_iosched_show(struct request_queue *, char *);
extern ssize_t elv_iosched_store(struct request_queue *, const char *, size_t);

extern int elevator_init(struct request_queue *, char *);
extern void elevator_exit(struct request_queue *, struct elevator_queue *);
extern bool elv_bio_merge_ok(struct request *, struct bio *);
extern struct elevator_queue *elevator_alloc(struct request_queue *,
					struct elevator_type *);

/*
 * Helper functions.
 */
extern struct request *elv_rb_former_request(struct request_queue *, struct request *);
extern struct request *elv_rb_latter_request(struct request_queue *, struct request *);

/*
 * rb support functions.
 */
extern void elv_rb_add(struct rb_root *, struct request *);
extern void elv_rb_del(struct rb_root *, struct request *);
extern struct request *elv_rb_find(struct rb_root *, sector_t);

/*
 * Insertion selection
 */
#define ELEVATOR_INSERT_FRONT	1
#define ELEVATOR_INSERT_BACK	2
#define ELEVATOR_INSERT_SORT	3
#define ELEVATOR_INSERT_REQUEUE	4
#define ELEVATOR_INSERT_FLUSH	5
#define ELEVATOR_INSERT_SORT_MERGE	6

/*
 * return values from elevator_may_queue_fn
 */
enum {
	ELV_MQUEUE_MAY,
	ELV_MQUEUE_NO,
	ELV_MQUEUE_MUST,
};

#define rq_end_sector(rq)	(blk_rq_pos(rq) + blk_rq_sectors(rq))
#define rb_entry_rq(node)	rb_entry((node), struct request, rb_node)

#define rq_entry_fifo(ptr)	list_entry((ptr), struct request, queuelist)
#define rq_fifo_clear(rq)	list_del_init(&(rq)->queuelist)

#else /* CONFIG_BLOCK */

static inline void load_default_elevator_module(void) { }

#endif /* CONFIG_BLOCK */
#endif
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_ELEVATOR_H
	2	#define _LINUX_ELEVATOR_H
	3
4a893e83	4	#include <linux/percpu.h>
242d98f0	5	#include <linux/hashtable.h>
4a893e83	6
9361401e DH	7	#ifdef CONFIG_BLOCK
9361401e DH	8
7e5a8794	9	struct io_cq;
d50235b7	10	struct elevator_type;
d332ce09 OS	11	#ifdef CONFIG_BLK_DEBUG_FS
	12	struct blk_mq_debugfs_attr;
	13	#endif
7e5a8794	14
34fe7c05 CH	15	/*
	16	* Return values from elevator merger
	17	*/
	18	enum elv_merge {
	19	ELEVATOR_NO_MERGE = 0,
	20	ELEVATOR_FRONT_MERGE = 1,
	21	ELEVATOR_BACK_MERGE = 2,
1e739730	22	ELEVATOR_DISCARD_MERGE = 3,
34fe7c05 CH	23	};
	24
	25	typedef enum elv_merge (elevator_merge_fn) (struct request_queue , struct request *,
1da177e4 LT	26	struct bio *);
1da177e4 LT	27
165125e1	28	typedef void (elevator_merge_req_fn) (struct request_queue , struct request , struct request *);
1da177e4	29
34fe7c05	30	typedef void (elevator_merged_fn) (struct request_queue , struct request , enum elv_merge);
1da177e4	31
72ef799b TE	32	typedef int (elevator_allow_bio_merge_fn) (struct request_queue *,
	33	struct request , struct bio );
	34
	35	typedef int (elevator_allow_rq_merge_fn) (struct request_queue *,
	36	struct request , struct request );
da775265	37
812d4026 DS	38	typedef void (elevator_bio_merged_fn) (struct request_queue *,
	39	struct request , struct bio );
	40
165125e1	41	typedef int (elevator_dispatch_fn) (struct request_queue *, int);
1da177e4	42
165125e1	43	typedef void (elevator_add_req_fn) (struct request_queue , struct request );
165125e1 JA	44	typedef struct request (elevator_request_list_fn) (struct request_queue , struct request *);
165125e1 JA	45	typedef void (elevator_completed_req_fn) (struct request_queue , struct request );
ef295ecf	46	typedef int (elevator_may_queue_fn) (struct request_queue *, unsigned int);
1da177e4	47
9b84cacd	48	typedef void (elevator_init_icq_fn) (struct io_cq *);
7e5a8794	49	typedef void (elevator_exit_icq_fn) (struct io_cq *);
852c788f TH	50	typedef int (elevator_set_req_fn) (struct request_queue , struct request ,
852c788f TH	51	struct bio *, gfp_t);
bb37b94c	52	typedef void (elevator_put_req_fn) (struct request *);
165125e1 JA	53	typedef void (elevator_activate_req_fn) (struct request_queue , struct request );
165125e1 JA	54	typedef void (elevator_deactivate_req_fn) (struct request_queue , struct request );
1da177e4	55
d50235b7 JM	56	typedef int (elevator_init_fn) (struct request_queue *,
d50235b7 JM	57	struct elevator_type *e);
b374d18a	58	typedef void (elevator_exit_fn) (struct elevator_queue *);
0bb97947	59	typedef void (elevator_registered_fn) (struct request_queue *);
1da177e4 LT	60
	61	struct elevator_ops
	62	{
	63	elevator_merge_fn *elevator_merge_fn;
	64	elevator_merged_fn *elevator_merged_fn;
	65	elevator_merge_req_fn *elevator_merge_req_fn;
72ef799b TE	66	elevator_allow_bio_merge_fn *elevator_allow_bio_merge_fn;
72ef799b TE	67	elevator_allow_rq_merge_fn *elevator_allow_rq_merge_fn;
812d4026	68	elevator_bio_merged_fn *elevator_bio_merged_fn;
1da177e4	69
8922e16c	70	elevator_dispatch_fn *elevator_dispatch_fn;
1da177e4	71	elevator_add_req_fn *elevator_add_req_fn;
8922e16c	72	elevator_activate_req_fn *elevator_activate_req_fn;
1da177e4 LT	73	elevator_deactivate_req_fn *elevator_deactivate_req_fn;
1da177e4 LT	74
1da177e4 LT	75	elevator_completed_req_fn *elevator_completed_req_fn;
	76
	77	elevator_request_list_fn *elevator_former_req_fn;
	78	elevator_request_list_fn *elevator_latter_req_fn;
	79
f1f8cc94 TH	80	elevator_init_icq_fn elevator_init_icq_fn; / see iocontext.h */
f1f8cc94 TH	81	elevator_exit_icq_fn elevator_exit_icq_fn; / ditto */
7e5a8794	82
1da177e4 LT	83	elevator_set_req_fn *elevator_set_req_fn;
	84	elevator_put_req_fn *elevator_put_req_fn;
	85
	86	elevator_may_queue_fn *elevator_may_queue_fn;
	87
	88	elevator_init_fn *elevator_init_fn;
	89	elevator_exit_fn *elevator_exit_fn;
0bb97947	90	elevator_registered_fn *elevator_registered_fn;
1da177e4 LT	91	};
1da177e4 LT	92
bd166ef1 JA	93	struct blk_mq_alloc_data;
	94	struct blk_mq_hw_ctx;
	95
	96	struct elevator_mq_ops {
	97	int (init_sched)(struct request_queue , struct elevator_type *);
	98	void (exit_sched)(struct elevator_queue );
ee056f98 OS	99	int (init_hctx)(struct blk_mq_hw_ctx , unsigned int);
ee056f98 OS	100	void (exit_hctx)(struct blk_mq_hw_ctx , unsigned int);
bd166ef1 JA	101
	102	bool (allow_merge)(struct request_queue , struct request , struct bio );
	103	bool (bio_merge)(struct blk_mq_hw_ctx , struct bio *);
	104	int (request_merge)(struct request_queue q, struct request *, struct bio );
34fe7c05	105	void (request_merged)(struct request_queue , struct request *, enum elv_merge);
bd166ef1	106	void (requests_merged)(struct request_queue , struct request , struct request );
5bbf4e5a CH	107	void (limit_depth)(unsigned int, struct blk_mq_alloc_data );
5bbf4e5a CH	108	void (prepare_request)(struct request , struct bio *bio);
7b9e9361	109	void (finish_request)(struct request );
bd166ef1	110	void (insert_requests)(struct blk_mq_hw_ctx , struct list_head *, bool);
c13660a0	111	struct request (dispatch_request)(struct blk_mq_hw_ctx *);
bd166ef1	112	bool (has_work)(struct blk_mq_hw_ctx );
c05f8525	113	void (completed_request)(struct request );
bd166ef1 JA	114	void (started_request)(struct request );
	115	void (requeue_request)(struct request );
	116	struct request (former_request)(struct request_queue , struct request );
	117	struct request (next_request)(struct request_queue , struct request );
bd166ef1 JA	118	void (init_icq)(struct io_cq );
	119	void (exit_icq)(struct io_cq );
	120	};
	121
1da177e4 LT	122	#define ELV_NAME_MAX (16)
1da177e4 LT	123
e572ec7e AV	124	struct elv_fs_entry {
e572ec7e AV	125	struct attribute attr;
b374d18a JA	126	ssize_t (show)(struct elevator_queue , char *);
b374d18a JA	127	ssize_t (store)(struct elevator_queue , const char *, size_t);
e572ec7e AV	128	};
e572ec7e AV	129
1da177e4 LT	130	/*
	131	* identifies an elevator type, such as AS or deadline
	132	*/
	133	struct elevator_type
	134	{
3d3c2379 TH	135	/* managed by elevator core */
	136	struct kmem_cache *icq_cache;
	137
	138	/* fields provided by elevator implementation */
c51ca6cf JA	139	union {
c51ca6cf JA	140	struct elevator_ops sq;
bd166ef1	141	struct elevator_mq_ops mq;
c51ca6cf	142	} ops;
f1f8cc94 TH	143	size_t icq_size; /* see iocontext.h */
f1f8cc94 TH	144	size_t icq_align; /* ditto */
e572ec7e	145	struct elv_fs_entry *elevator_attrs;
1da177e4 LT	146	char elevator_name[ELV_NAME_MAX];
1da177e4 LT	147	struct module *elevator_owner;
bd166ef1	148	bool uses_mq;
d332ce09 OS	149	#ifdef CONFIG_BLK_DEBUG_FS
	150	const struct blk_mq_debugfs_attr *queue_debugfs_attrs;
	151	const struct blk_mq_debugfs_attr *hctx_debugfs_attrs;
	152	#endif
3d3c2379 TH	153
3d3c2379 TH	154	/* managed by elevator core */
9bd2bbc0	155	char icq_cache_name[ELV_NAME_MAX + 6]; /* elvname + "_io_cq" */
22f746e2	156	struct list_head list;
1da177e4 LT	157	};
1da177e4 LT	158
242d98f0 SL	159	#define ELV_HASH_BITS 6
242d98f0 SL	160
70b3ea05 JA	161	void elv_rqhash_del(struct request_queue q, struct request rq);
	162	void elv_rqhash_add(struct request_queue q, struct request rq);
	163	void elv_rqhash_reposition(struct request_queue q, struct request rq);
	164	struct request elv_rqhash_find(struct request_queue q, sector_t offset);
	165
1da177e4	166	/*
54069588	167	* each queue has an elevator_queue associated with it
1da177e4 LT	168	*/
	169	struct elevator_queue
	170	{
22f746e2	171	struct elevator_type *type;
1da177e4 LT	172	void *elevator_data;
1da177e4 LT	173	struct kobject kobj;
3d1ab40f	174	struct mutex sysfs_lock;
430c62fb	175	unsigned int registered:1;
bd166ef1	176	unsigned int uses_mq:1;
242d98f0	177	DECLARE_HASHTABLE(hash, ELV_HASH_BITS);
1da177e4 LT	178	};
	179
	180	/*
	181	* block elevator interface
	182	*/
165125e1 JA	183	extern void elv_dispatch_sort(struct request_queue , struct request );
165125e1 JA	184	extern void elv_dispatch_add_tail(struct request_queue , struct request );
7eaceacc JA	185	extern void elv_add_request(struct request_queue , struct request , int);
7eaceacc JA	186	extern void __elv_add_request(struct request_queue , struct request , int);
34fe7c05 CH	187	extern enum elv_merge elv_merge(struct request_queue , struct request *,
34fe7c05 CH	188	struct bio *);
165125e1	189	extern void elv_merge_requests(struct request_queue , struct request ,
1da177e4	190	struct request *);
34fe7c05 CH	191	extern void elv_merged_request(struct request_queue , struct request ,
34fe7c05 CH	192	enum elv_merge);
812d4026 DS	193	extern void elv_bio_merged(struct request_queue q, struct request ,
812d4026 DS	194	struct bio *);
bd166ef1	195	extern bool elv_attempt_insert_merge(struct request_queue , struct request );
165125e1	196	extern void elv_requeue_request(struct request_queue , struct request );
165125e1 JA	197	extern struct request elv_former_request(struct request_queue , struct request *);
	198	extern struct request elv_latter_request(struct request_queue , struct request *);
	199	extern int elv_register_queue(struct request_queue *q);
	200	extern void elv_unregister_queue(struct request_queue *q);
ef295ecf	201	extern int elv_may_queue(struct request_queue *, unsigned int);
165125e1	202	extern void elv_completed_request(struct request_queue , struct request );
852c788f TH	203	extern int elv_set_request(struct request_queue q, struct request rq,
852c788f TH	204	struct bio *bio, gfp_t gfp_mask);
165125e1	205	extern void elv_put_request(struct request_queue , struct request );
26308eab	206	extern void elv_drain_elevator(struct request_queue *);
1da177e4 LT	207
	208	/*
	209	* io scheduler registration
	210	*/
bb813f4c	211	extern void __init load_default_elevator_module(void);
e567bf71	212	extern int elv_register(struct elevator_type *);
1da177e4 LT	213	extern void elv_unregister(struct elevator_type *);
	214
	215	/*
	216	* io scheduler sysfs switching
	217	*/
165125e1 JA	218	extern ssize_t elv_iosched_show(struct request_queue , char );
165125e1 JA	219	extern ssize_t elv_iosched_store(struct request_queue , const char , size_t);
1da177e4	220
165125e1	221	extern int elevator_init(struct request_queue , char );
54d5329d	222	extern void elevator_exit(struct request_queue , struct elevator_queue );
72ef799b	223	extern bool elv_bio_merge_ok(struct request , struct bio );
d50235b7 JM	224	extern struct elevator_queue elevator_alloc(struct request_queue ,
d50235b7 JM	225	struct elevator_type *);
1da177e4	226
2e662b65 JA	227	/*
	228	* Helper functions.
	229	*/
165125e1 JA	230	extern struct request elv_rb_former_request(struct request_queue , struct request *);
165125e1 JA	231	extern struct request elv_rb_latter_request(struct request_queue , struct request *);
2e662b65 JA	232
	233	/*
	234	* rb support functions.
	235	*/
796d5116	236	extern void elv_rb_add(struct rb_root , struct request );
2e662b65 JA	237	extern void elv_rb_del(struct rb_root , struct request );
	238	extern struct request elv_rb_find(struct rb_root , sector_t);
	239
1da177e4 LT	240	/*
	241	* Insertion selection
	242	*/
	243	#define ELEVATOR_INSERT_FRONT 1
	244	#define ELEVATOR_INSERT_BACK 2
	245	#define ELEVATOR_INSERT_SORT 3
797e7dbb	246	#define ELEVATOR_INSERT_REQUEUE 4
ae1b1539	247	#define ELEVATOR_INSERT_FLUSH 5
5e84ea3a	248	#define ELEVATOR_INSERT_SORT_MERGE 6
1da177e4 LT	249
	250	/*
	251	* return values from elevator_may_queue_fn
	252	*/
	253	enum {
	254	ELV_MQUEUE_MAY,
	255	ELV_MQUEUE_NO,
	256	ELV_MQUEUE_MUST,
	257	};
	258
2e46e8b2	259	#define rq_end_sector(rq) (blk_rq_pos(rq) + blk_rq_sectors(rq))
2e662b65	260	#define rb_entry_rq(node) rb_entry((node), struct request, rb_node)
1b47f531	261
1fbfdfcd	262	#define rq_entry_fifo(ptr) list_entry((ptr), struct request, queuelist)
d9a74df5	263	#define rq_fifo_clear(rq) list_del_init(&(rq)->queuelist)
1fbfdfcd	264
bb813f4c TH	265	#else /* CONFIG_BLOCK */
	266
	267	static inline void load_default_elevator_module(void) { }
	268
9361401e	269	#endif /* CONFIG_BLOCK */
1da177e4	270	#endif