#ifndef _SCSI_SCSI_CMND_H
  #define _SCSI_SCSI_CMND_H
  
  #include <linux/dma-mapping.h>

  #include <linux/blkdev.h>

  #include <linux/list.h>
  #include <linux/types.h>

  #include <linux/timer.h>

  #include <linux/scatterlist.h>

  struct Scsi_Host;

  struct scsi_device;

  /*
   * MAX_COMMAND_SIZE is:
   * The longest fixed-length SCSI CDB as per the SCSI standard.
   * fixed-length means: commands that their size can be determined
   * by their opcode and the CDB does not carry a length specifier, (unlike
   * the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly
   * true and the SCSI standard also defines extended commands and
   * vendor specific commands that can be bigger than 16 bytes. The kernel
   * will support these using the same infrastructure used for VARLEN CDB's.
   * So in effect MAX_COMMAND_SIZE means the maximum size command scsi-ml
   * supports without specifying a cmd_len by ULD's
   */
  #define MAX_COMMAND_SIZE 16
  #if (MAX_COMMAND_SIZE > BLK_MAX_CDB)
  # error MAX_COMMAND_SIZE can not be bigger than BLK_MAX_CDB
  #endif

  struct scsi_data_buffer {
  	struct sg_table table;
  	unsigned length;
  	int resid;
  };

  
  /* embedded in scsi_cmnd */
  struct scsi_pointer {
  	char *ptr;		/* data pointer */
  	int this_residual;	/* left in this buffer */
  	struct scatterlist *buffer;	/* which buffer */
  	int buffers_residual;	/* how many buffers left */
  
          dma_addr_t dma_handle;
  
  	volatile int Status;
  	volatile int Message;
  	volatile int have_data_in;
  	volatile int sent_command;
  	volatile int phase;
  };
  
  struct scsi_cmnd {

  	struct scsi_device *device;

  	struct list_head list;  /* scsi_cmnd participates in queue lists */

  	struct list_head eh_entry; /* entry for the host eh_cmd_q */

  	int eh_eflags;		/* Used by error handlr */

  
  	/*

  	 * A SCSI Command is assigned a nonzero serial_number before passed
  	 * to the driver's queue command function.  The serial_number is
  	 * cleared when scsi_done is entered indicating that the command

  	 * has been completed.  It is a bug for LLDDs to use this number
  	 * for purposes other than printk (and even that is only useful
  	 * for debugging).

  	 */
  	unsigned long serial_number;

  	/*
  	 * This is set to jiffies as it was when the command was first
  	 * allocated.  It is used to time how long the command has
  	 * been outstanding
  	 */
  	unsigned long jiffies_at_alloc;

  
  	int retries;
  	int allowed;

  	unsigned char prot_op;
  	unsigned char prot_type;

  	unsigned short cmd_len;

  	enum dma_data_direction sc_data_direction;

  
  	/* These elements define the operation we are about to perform */

  	unsigned char *cmnd;

  
  	/* These elements define the operation we ultimately want to perform */

  	struct scsi_data_buffer sdb;

  	struct scsi_data_buffer *prot_sdb;

  	unsigned underflow;	/* Return error if less than
  				   this amount is transferred */

  
  	unsigned transfersize;	/* How much we are guaranteed to
  				   transfer with each SCSI transfer
  				   (ie, between disconnect / 
  				   reconnects.   Probably == sector
  				   size */

  	struct request *request;	/* The command we are
  				   	   working on */
  
  #define SCSI_SENSE_BUFFERSIZE 	96

  	unsigned char *sense_buffer;

  				/* obtained by REQUEST SENSE when
  				 * CHECK CONDITION is received on original
  				 * command (auto-sense) */

  
  	/* Low-level done function - can be used by low-level driver to point
  	 *        to completion function.  Not used by mid/upper level code. */
  	void (*scsi_done) (struct scsi_cmnd *);
  
  	/*
  	 * The following fields can be written to by the host specific code. 
  	 * Everything else should be left alone. 
  	 */
  	struct scsi_pointer SCp;	/* Scratchpad used by some host adapters */
  
  	unsigned char *host_scribble;	/* The host adapter is allowed to

  					 * call scsi_malloc and get some memory
  					 * and hang it here.  The host adapter
  					 * is also expected to call scsi_free
  					 * to release this memory.  (The memory
  					 * obtained by scsi_malloc is guaranteed
  					 * to be at an address < 16Mb). */

  
  	int result;		/* Status code from lower level driver */
  
  	unsigned char tag;	/* SCSI-II queued command tag */

  };

  extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t);

  extern struct scsi_cmnd *__scsi_get_command(struct Scsi_Host *, gfp_t);

  extern void scsi_put_command(struct scsi_cmnd *);

  extern void __scsi_put_command(struct Scsi_Host *, struct scsi_cmnd *,
  			       struct device *);

  extern void scsi_finish_command(struct scsi_cmnd *cmd);

  extern void *scsi_kmap_atomic_sg(struct scatterlist *sg, int sg_count,
  				 size_t *offset, size_t *len);
  extern void scsi_kunmap_atomic_sg(void *virt);

  extern int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask);
  extern void scsi_release_buffers(struct scsi_cmnd *cmd);

  extern int scsi_dma_map(struct scsi_cmnd *cmd);
  extern void scsi_dma_unmap(struct scsi_cmnd *cmd);

  struct scsi_cmnd *scsi_allocate_command(gfp_t gfp_mask);
  void scsi_free_command(gfp_t gfp_mask, struct scsi_cmnd *cmd);

  static inline unsigned scsi_sg_count(struct scsi_cmnd *cmd)
  {
  	return cmd->sdb.table.nents;
  }
  
  static inline struct scatterlist *scsi_sglist(struct scsi_cmnd *cmd)
  {
  	return cmd->sdb.table.sgl;
  }
  
  static inline unsigned scsi_bufflen(struct scsi_cmnd *cmd)
  {
  	return cmd->sdb.length;
  }

  
  static inline void scsi_set_resid(struct scsi_cmnd *cmd, int resid)
  {

  	cmd->sdb.resid = resid;

  }
  
  static inline int scsi_get_resid(struct scsi_cmnd *cmd)
  {

  	return cmd->sdb.resid;

  }
  
  #define scsi_for_each_sg(cmd, sg, nseg, __i)			\

  	for_each_sg(scsi_sglist(cmd), sg, nseg, __i)

  static inline int scsi_bidi_cmnd(struct scsi_cmnd *cmd)
  {
  	return blk_bidi_rq(cmd->request) &&
  		(cmd->request->next_rq->special != NULL);
  }
  
  static inline struct scsi_data_buffer *scsi_in(struct scsi_cmnd *cmd)
  {
  	return scsi_bidi_cmnd(cmd) ?
  		cmd->request->next_rq->special : &cmd->sdb;
  }
  
  static inline struct scsi_data_buffer *scsi_out(struct scsi_cmnd *cmd)
  {
  	return &cmd->sdb;
  }

  static inline int scsi_sg_copy_from_buffer(struct scsi_cmnd *cmd,
  					   void *buf, int buflen)
  {
  	return sg_copy_from_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
  				   buf, buflen);
  }
  
  static inline int scsi_sg_copy_to_buffer(struct scsi_cmnd *cmd,
  					 void *buf, int buflen)
  {
  	return sg_copy_to_buffer(scsi_sglist(cmd), scsi_sg_count(cmd),
  				 buf, buflen);
  }

  /*
   * The operations below are hints that tell the controller driver how
   * to handle I/Os with DIF or similar types of protection information.
   */
  enum scsi_prot_operations {
  	/* Normal I/O */
  	SCSI_PROT_NORMAL = 0,
  
  	/* OS-HBA: Protected, HBA-Target: Unprotected */
  	SCSI_PROT_READ_INSERT,
  	SCSI_PROT_WRITE_STRIP,
  
  	/* OS-HBA: Unprotected, HBA-Target: Protected */
  	SCSI_PROT_READ_STRIP,
  	SCSI_PROT_WRITE_INSERT,
  
  	/* OS-HBA: Protected, HBA-Target: Protected */
  	SCSI_PROT_READ_PASS,
  	SCSI_PROT_WRITE_PASS,

  };
  
  static inline void scsi_set_prot_op(struct scsi_cmnd *scmd, unsigned char op)
  {
  	scmd->prot_op = op;
  }
  
  static inline unsigned char scsi_get_prot_op(struct scsi_cmnd *scmd)
  {
  	return scmd->prot_op;
  }
  
  /*
   * The controller usually does not know anything about the target it
   * is communicating with.  However, when DIX is enabled the controller
   * must be know target type so it can verify the protection
   * information passed along with the I/O.
   */
  enum scsi_prot_target_type {
  	SCSI_PROT_DIF_TYPE0 = 0,
  	SCSI_PROT_DIF_TYPE1,
  	SCSI_PROT_DIF_TYPE2,
  	SCSI_PROT_DIF_TYPE3,
  };
  
  static inline void scsi_set_prot_type(struct scsi_cmnd *scmd, unsigned char type)
  {
  	scmd->prot_type = type;
  }
  
  static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd)
  {
  	return scmd->prot_type;
  }
  
  static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd)
  {

  	return blk_rq_pos(scmd->request);

  }

  static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)
  {
  	return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0;
  }
  
  static inline struct scatterlist *scsi_prot_sglist(struct scsi_cmnd *cmd)
  {
  	return cmd->prot_sdb ? cmd->prot_sdb->table.sgl : NULL;
  }
  
  static inline struct scsi_data_buffer *scsi_prot(struct scsi_cmnd *cmd)
  {
  	return cmd->prot_sdb;
  }
  
  #define scsi_for_each_prot_sg(cmd, sg, nseg, __i)		\
  	for_each_sg(scsi_prot_sglist(cmd), sg, nseg, __i)

  static inline void set_msg_byte(struct scsi_cmnd *cmd, char status)
  {
  	cmd->result |= status << 8;
  }
  
  static inline void set_host_byte(struct scsi_cmnd *cmd, char status)
  {
  	cmd->result |= status << 16;
  }
  
  static inline void set_driver_byte(struct scsi_cmnd *cmd, char status)
  {
  	cmd->result |= status << 24;
  }

  #endif /* _SCSI_SCSI_CMND_H */