block: move elevator.h to block/

Except for the features passed to blk_queue_required_elevator_features,
elevator.h is only needed internally to the block layer.  Move the
ELEVATOR_F_* definitions to blkdev.h, and the move elevator.h to
block/, dropping all the spurious includes outside of that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

2 files changed, 9 insertions, 182 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 4bcbb1ae2d66..d815238f61ed 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -251,8 +251,6 @@ static inline unsigned short req_get_ioprio(struct request *req)
 	return req->ioprio;
 }
 
-#include <linux/elevator.h>
-
 struct bio_vec;
 
 enum blk_eh_timer_return {
@@ -1124,6 +1122,15 @@ extern void blk_queue_dma_alignment(struct request_queue *, int);
 extern void blk_queue_update_dma_alignment(struct request_queue *, int);
 extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
 extern void blk_queue_write_cache(struct request_queue *q, bool enabled, bool fua);
+
+/*
+ * Elevator features for blk_queue_required_elevator_features:
+ */
+/* Supports zoned block devices sequential write constraint */
+#define ELEVATOR_F_ZBD_SEQ_WRITE	(1U << 0)
+/* Supports scheduling on multiple hardware queues */
+#define ELEVATOR_F_MQ_AWARE		(1U << 1)
+
 extern void blk_queue_required_elevator_features(struct request_queue *q,
 						 unsigned int features);
 extern bool blk_queue_can_use_dma_map_merging(struct request_queue *q,
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
deleted file mode 100644
index 80633f3b600c..000000000000
--- a/include/linux/elevator.h
+++ /dev/null
@@ -1,180 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#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,
-};
-
-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);
-	void (*depth_updated)(struct blk_mq_hw_ctx *);
-
-	bool (*allow_merge)(struct request_queue *, struct request *, struct bio *);
-	bool (*bio_merge)(struct request_queue *, struct bio *, unsigned int);
-	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 *);
-	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 *, u64);
-	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 */
-	struct elevator_mq_ops ops;
-
-	size_t icq_size;	/* see iocontext.h */
-	size_t icq_align;	/* ditto */
-	struct elv_fs_entry *elevator_attrs;
-	const char *elevator_name;
-	const char *elevator_alias;
-	const unsigned int elevator_features;
-	struct module *elevator_owner;
-#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;
-	DECLARE_HASHTABLE(hash, ELV_HASH_BITS);
-};
-
-/*
- * block elevator interface
- */
-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 bool elv_attempt_insert_merge(struct request_queue *, struct request *,
-				     struct list_head *);
-extern struct request *elv_former_request(struct request_queue *, struct request *);
-extern struct request *elv_latter_request(struct request_queue *, struct request *);
-void elevator_init_mq(struct request_queue *q);
-
-/*
- * io scheduler registration
- */
-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 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
-
-#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)
-
-/*
- * Elevator features.
- */
-
-/* Supports zoned block devices sequential write constraint */
-#define ELEVATOR_F_ZBD_SEQ_WRITE	(1U << 0)
-/* Supports scheduling on multiple hardware queues */
-#define ELEVATOR_F_MQ_AWARE		(1U << 1)
-
-#endif /* CONFIG_BLOCK */
-#endif