/*
   * Internal header file for device mapper
   *
   * Copyright (C) 2016 Red Hat, Inc. All rights reserved.
   *
   * This file is released under the LGPL.
   */
  
  #ifndef DM_RQ_INTERNAL_H
  #define DM_RQ_INTERNAL_H
  
  #include <linux/bio.h>
  #include <linux/kthread.h>
  
  #include "dm-stats.h"
  
  struct mapped_device;
  
  /*
   * One of these is allocated per request.
   */
  struct dm_rq_target_io {
  	struct mapped_device *md;
  	struct dm_target *ti;
  	struct request *orig, *clone;
  	struct kthread_work work;
  	int error;
  	union map_info info;
  	struct dm_stats_aux stats_aux;
  	unsigned long duration_jiffies;
  	unsigned n_sectors;
  };
  
  /*
   * For request-based dm - the bio clones we allocate are embedded in these
   * structs.
   *
   * We allocate these with bio_alloc_bioset, using the front_pad parameter when
   * the bioset is created - this means the bio has to come at the end of the
   * struct.
   */
  struct dm_rq_clone_bio_info {
  	struct bio *orig;
  	struct dm_rq_target_io *tio;
  	struct bio clone;
  };
  
  bool dm_use_blk_mq_default(void);
  bool dm_use_blk_mq(struct mapped_device *md);
  
  int dm_old_init_request_queue(struct mapped_device *md);

  int dm_mq_init_request_queue(struct mapped_device *md, struct dm_table *t);

  void dm_mq_cleanup_mapped_device(struct mapped_device *md);
  
  void dm_start_queue(struct request_queue *q);
  void dm_stop_queue(struct request_queue *q);

  void dm_mq_kick_requeue_list(struct mapped_device *md);

  unsigned dm_get_reserved_rq_based_ios(void);
  
  ssize_t dm_attr_rq_based_seq_io_merge_deadline_show(struct mapped_device *md, char *buf);
  ssize_t dm_attr_rq_based_seq_io_merge_deadline_store(struct mapped_device *md,
  						     const char *buf, size_t count);
  
  #endif