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

  /*
   *  BSG helper library
   *
   *  Copyright (C) 2008   James Smart, Emulex Corporation
   *  Copyright (C) 2011   Red Hat, Inc.  All rights reserved.
   *  Copyright (C) 2011   Mike Christie

   */
  #ifndef _BLK_BSG_
  #define _BLK_BSG_
  
  #include <linux/blkdev.h>

  #include <scsi/scsi_request.h>

  
  struct request;
  struct device;
  struct scatterlist;
  struct request_queue;

  typedef int (bsg_job_fn) (struct bsg_job *);
  typedef enum blk_eh_timer_return (bsg_timeout_fn)(struct request *);

  struct bsg_buffer {
  	unsigned int payload_len;
  	int sg_cnt;
  	struct scatterlist *sg_list;
  };
  
  struct bsg_job {
  	struct device *dev;

  	struct kref kref;

  	unsigned int timeout;

  	/* Transport/driver specific request/reply structs */
  	void *request;
  	void *reply;
  
  	unsigned int request_len;
  	unsigned int reply_len;
  	/*
  	 * On entry : reply_len indicates the buffer size allocated for
  	 * the reply.
  	 *
  	 * Upon completion : the message handler must set reply_len
  	 *  to indicates the size of the reply to be returned to the
  	 *  caller.
  	 */
  
  	/* DMA payloads for the request/response */
  	struct bsg_buffer request_payload;
  	struct bsg_buffer reply_payload;

  	int result;
  	unsigned int reply_payload_rcv_len;

  	/* BIDI support */
  	struct request *bidi_rq;
  	struct bio *bidi_bio;

  	void *dd_data;		/* Used for driver-specific storage */
  };
  
  void bsg_job_done(struct bsg_job *job, int result,
  		  unsigned int reply_payload_rcv_len);

  struct request_queue *bsg_setup_queue(struct device *dev, const char *name,

  		bsg_job_fn *job_fn, bsg_timeout_fn *timeout, int dd_job_size);

  void bsg_remove_queue(struct request_queue *q);

  void bsg_job_put(struct bsg_job *job);
  int __must_check bsg_job_get(struct bsg_job *job);

  
  #endif