/* SPDX-License-Identifier: GPL-2.0 */

  #ifndef INT_BLK_MQ_H
  #define INT_BLK_MQ_H

  #include "blk-stat.h"

  #include "blk-mq-tag.h"

  struct blk_mq_tag_set;

  /**
   * struct blk_mq_ctx - State for a software queue facing the submitting CPUs
   */

  struct blk_mq_ctx {
  	struct {
  		spinlock_t		lock;
  		struct list_head	rq_list;
  	}  ____cacheline_aligned_in_smp;
  
  	unsigned int		cpu;
  	unsigned int		index_hw;

  
  	/* incremented at dispatch time */
  	unsigned long		rq_dispatched[2];
  	unsigned long		rq_merged;
  
  	/* incremented at completion time */
  	unsigned long		____cacheline_aligned_in_smp rq_completed[2];
  
  	struct request_queue	*queue;
  	struct kobject		kobj;

  } ____cacheline_aligned_in_smp;

  void blk_mq_freeze_queue(struct request_queue *q);

  void blk_mq_free_queue(struct request_queue *q);

  int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);

  void blk_mq_wake_waiters(struct request_queue *q);

  bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool);

  void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);

  bool blk_mq_get_driver_tag(struct request *rq);

  struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
  					struct blk_mq_ctx *start);

  
  /*
   * Internal helpers for allocating/freeing the request map
   */

  void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
  		     unsigned int hctx_idx);
  void blk_mq_free_rq_map(struct blk_mq_tags *tags);
  struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
  					unsigned int hctx_idx,
  					unsigned int nr_tags,
  					unsigned int reserved_tags);
  int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
  		     unsigned int hctx_idx, unsigned int depth);

  
  /*
   * Internal helpers for request insertion into sw queues
   */
  void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
  				bool at_head);

  void blk_mq_request_bypass_insert(struct request *rq, bool run_queue);

  void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
  				struct list_head *list);

  /* Used by blk_insert_cloned_request() to issue request directly */

  blk_status_t blk_mq_request_issue_directly(struct request *rq);

  void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
  				    struct list_head *list);

  /*
   * CPU -> queue mappings
   */

  extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);

  static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
  		int cpu)
  {
  	return q->queue_hw_ctx[q->mq_map[cpu]];
  }

  /*

   * sysfs helpers
   */

  extern void blk_mq_sysfs_init(struct request_queue *q);

  extern void blk_mq_sysfs_deinit(struct request_queue *q);

  extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q);

  extern int blk_mq_sysfs_register(struct request_queue *q);
  extern void blk_mq_sysfs_unregister(struct request_queue *q);

  extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);

  void blk_mq_release(struct request_queue *q);

  /**
   * blk_mq_rq_state() - read the current MQ_RQ_* state of a request
   * @rq: target request.
   */

  static inline enum mq_rq_state blk_mq_rq_state(struct request *rq)

  {

  	return READ_ONCE(rq->state);

  }

  static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
  					   unsigned int cpu)
  {
  	return per_cpu_ptr(q->queue_ctx, cpu);
  }
  
  /*
   * This assumes per-cpu software queueing queues. They could be per-node
   * as well, for instance. For now this is hardcoded as-is. Note that we don't
   * care about preemption, since we know the ctx's are persistent. This does
   * mean that we can't rely on ctx always matching the currently running CPU.
   */
  static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
  {
  	return __blk_mq_get_ctx(q, get_cpu());
  }
  
  static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
  {
  	put_cpu();
  }

  struct blk_mq_alloc_data {
  	/* input parameter */
  	struct request_queue *q;

  	blk_mq_req_flags_t flags;

  	unsigned int shallow_depth;

  
  	/* input & output parameter */
  	struct blk_mq_ctx *ctx;
  	struct blk_mq_hw_ctx *hctx;
  };

  static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
  {

  	if (data->flags & BLK_MQ_REQ_INTERNAL)
  		return data->hctx->sched_tags;

  	return data->hctx->tags;
  }

  static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
  {
  	return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
  }

  static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
  {
  	return hctx->nr_ctx && hctx->tags;
  }

  void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,

  		      unsigned int inflight[2]);
  void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
  			 unsigned int inflight[2]);

  static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx)
  {
  	struct request_queue *q = hctx->queue;
  
  	if (q->mq_ops->put_budget)
  		q->mq_ops->put_budget(hctx);
  }

  static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx)

  {
  	struct request_queue *q = hctx->queue;
  
  	if (q->mq_ops->get_budget)
  		return q->mq_ops->get_budget(hctx);

  	return true;

  }

  static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
  					   struct request *rq)
  {
  	blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag);
  	rq->tag = -1;
  
  	if (rq->rq_flags & RQF_MQ_INFLIGHT) {
  		rq->rq_flags &= ~RQF_MQ_INFLIGHT;
  		atomic_dec(&hctx->nr_active);
  	}
  }
  
  static inline void blk_mq_put_driver_tag_hctx(struct blk_mq_hw_ctx *hctx,
  				       struct request *rq)
  {
  	if (rq->tag == -1 || rq->internal_tag == -1)
  		return;
  
  	__blk_mq_put_driver_tag(hctx, rq);
  }
  
  static inline void blk_mq_put_driver_tag(struct request *rq)
  {
  	struct blk_mq_hw_ctx *hctx;
  
  	if (rq->tag == -1 || rq->internal_tag == -1)
  		return;
  
  	hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu);
  	__blk_mq_put_driver_tag(hctx, rq);
  }

  static inline void blk_mq_clear_mq_map(struct blk_mq_tag_set *set)
  {
  	int cpu;
  
  	for_each_possible_cpu(cpu)
  		set->mq_map[cpu] = 0;
  }

  #endif