pcmcia: CompactFlash driver for PA Semi Electra boards
[pv_ops_mirror.git] / drivers / scsi / arm / queue.h
blob3c519c9237b27410f07376efa5cf91dbe96916e4
1 /*
2 * linux/drivers/acorn/scsi/queue.h: queue handling
4 * Copyright (C) 1997 Russell King
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10 #ifndef QUEUE_H
11 #define QUEUE_H
13 typedef struct {
14 struct list_head head;
15 struct list_head free;
16 spinlock_t queue_lock;
17 void *alloc; /* start of allocated mem */
18 } Queue_t;
21 * Function: void queue_initialise (Queue_t *queue)
22 * Purpose : initialise a queue
23 * Params : queue - queue to initialise
25 extern int queue_initialise (Queue_t *queue);
28 * Function: void queue_free (Queue_t *queue)
29 * Purpose : free a queue
30 * Params : queue - queue to free
32 extern void queue_free (Queue_t *queue);
35 * Function: struct scsi_cmnd *queue_remove (queue)
36 * Purpose : removes first SCSI command from a queue
37 * Params : queue - queue to remove command from
38 * Returns : struct scsi_cmnd if successful (and a reference), or NULL if no command available
40 extern struct scsi_cmnd *queue_remove (Queue_t *queue);
43 * Function: struct scsi_cmnd *queue_remove_exclude_ref (queue, exclude)
44 * Purpose : remove a SCSI command from a queue
45 * Params : queue - queue to remove command from
46 * exclude - array of busy LUNs
47 * Returns : struct scsi_cmnd if successful (and a reference), or NULL if no command available
49 extern struct scsi_cmnd *queue_remove_exclude(Queue_t *queue,
50 unsigned long *exclude);
52 #define queue_add_cmd_ordered(queue,SCpnt) \
53 __queue_add(queue,SCpnt,(SCpnt)->cmnd[0] == REQUEST_SENSE)
54 #define queue_add_cmd_tail(queue,SCpnt) \
55 __queue_add(queue,SCpnt,0)
57 * Function: int __queue_add(Queue_t *queue, struct scsi_cmnd *SCpnt, int head)
58 * Purpose : Add a new command onto a queue
59 * Params : queue - destination queue
60 * SCpnt - command to add
61 * head - add command to head of queue
62 * Returns : 0 on error, !0 on success
64 extern int __queue_add(Queue_t *queue, struct scsi_cmnd *SCpnt, int head);
67 * Function: struct scsi_cmnd *queue_remove_tgtluntag (queue, target, lun, tag)
68 * Purpose : remove a SCSI command from the queue for a specified target/lun/tag
69 * Params : queue - queue to remove command from
70 * target - target that we want
71 * lun - lun on device
72 * tag - tag on device
73 * Returns : struct scsi_cmnd if successful, or NULL if no command satisfies requirements
75 extern struct scsi_cmnd *queue_remove_tgtluntag(Queue_t *queue, int target,
76 int lun, int tag);
79 * Function: queue_remove_all_target(queue, target)
80 * Purpose : remove all SCSI commands from the queue for a specified target
81 * Params : queue - queue to remove command from
82 * target - target device id
83 * Returns : nothing
85 extern void queue_remove_all_target(Queue_t *queue, int target);
88 * Function: int queue_probetgtlun (queue, target, lun)
89 * Purpose : check to see if we have a command in the queue for the specified
90 * target/lun.
91 * Params : queue - queue to look in
92 * target - target we want to probe
93 * lun - lun on target
94 * Returns : 0 if not found, != 0 if found
96 extern int queue_probetgtlun (Queue_t *queue, int target, int lun);
99 * Function: int queue_remove_cmd (Queue_t *queue, struct scsi_cmnd *SCpnt)
100 * Purpose : remove a specific command from the queues
101 * Params : queue - queue to look in
102 * SCpnt - command to find
103 * Returns : 0 if not found
105 int queue_remove_cmd(Queue_t *queue, struct scsi_cmnd *SCpnt);
107 #endif /* QUEUE_H */