/*
* linux/drivers/acorn/scsi/queue.h: queue handling
*
* Copyright (C) 1997 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#ifndef QUEUE_H
#define QUEUE_H
typedef struct {
struct list_head head;
struct list_head free;
spinlock_t queue_lock;
void *alloc; /* start of allocated mem */
} Queue_t;
/*
* Function: void queue_initialise (Queue_t *queue)
* Purpose : initialise a queue
* Params : queue - queue to initialise
*/
extern int queue_initialise (Queue_t *queue);
/*
* Function: void queue_free (Queue_t *queue)
* Purpose : free a queue
* Params : queue - queue to free
*/
extern void queue_free (Queue_t *queue);
/*
* Function: Scsi_Cmnd *queue_remove (queue)
* Purpose : removes first SCSI command from a queue
* Params : queue - queue to remove command from
* Returns : Scsi_Cmnd if successful (and a reference), or NULL if no command available
*/
extern Scsi_Cmnd *queue_remove (Queue_t *queue);
/*
* Function: Scsi_Cmnd *queue_remove_exclude_ref (queue, exclude)
* Purpose : remove a SCSI command from a queue
* Params : queue - queue to remove command from
* exclude - array of busy LUNs
* Returns : Scsi_Cmnd if successful (and a reference), or NULL if no command available
*/
extern Scsi_Cmnd *queue_remove_exclude (Queue_t *queue, unsigned long *exclude);
#define queue_add_cmd_ordered(queue,SCpnt) \
__queue_add(queue,SCpnt,(SCpnt)->cmnd[0] == REQUEST_SENSE)
#define queue_add_cmd_tail(queue,SCpnt) \
__queue_add(queue,SCpnt,0)
/*
* Function: int __queue_add(Queue_t *queue, Scsi_Cmnd *SCpnt, int head)
* Purpose : Add a new command onto a queue
* Params : queue - destination queue
* SCpnt - command to add
* head - add command to head of queue
* Returns : 0 on error, !0 on success
*/
extern int __queue_add(Queue_t *queue, Scsi_Cmnd *SCpnt, int head);
/*
* Function: Scsi_Cmnd *queue_remove_tgtluntag (queue, target, lun, tag)
* Purpose : remove a SCSI command from the queue for a specified target/lun/tag
* Params : queue - queue to remove command from
* target - target that we want
* lun - lun on device
* tag - tag on device
* Returns : Scsi_Cmnd if successful, or NULL if no command satisfies requirements
*/
extern Scsi_Cmnd *queue_remove_tgtluntag (Queue_t *queue, int target, int lun, int tag);
/*
* Function: queue_remove_all_target(queue, target)
* Purpose : remove all SCSI commands from the queue for a specified target
* Params : queue - queue to remove command from
* target - target device id
* Returns : nothing
*/
extern void queue_remove_all_target(Queue_t *queue, int target);
/*
* Function: int queue_probetgtlun (queue, target, lun)
* Purpose : check to see if we have a command in the queue for the specified
* target/lun.
* Params : queue - queue to look in
* target - target we want to probe
* lun - lun on target
* Returns : 0 if not found, != 0 if found
*/
extern int queue_probetgtlun (Queue_t *queue, int target, int lun);
/*
* Function: int queue_remove_cmd (Queue_t *queue, Scsi_Cmnd *SCpnt)
* Purpose : remove a specific command from the queues
* Params : queue - queue to look in
* SCpnt - command to find
* Returns : 0 if not found
*/
int queue_remove_cmd(Queue_t *queue, Scsi_Cmnd *SCpnt);
#endif /* QUEUE_H */
