scsi/arm/queue.c

3  *  linux/drivers/acorn/scsi/queue.c: queue handling primitives
50 #include "queue.h"
55  * Function: void queue_initialise (Queue_t *queue)
56  * Purpose : initialise a queue
57  * Params  : queue - queue to initialise
59 int queue_initialise (Queue_t *queue)
64 	spin_lock_init(&queue->queue_lock);
65 	INIT_LIST_HEAD(&queue->head);
66 	INIT_LIST_HEAD(&queue->free);
74 	queue->alloc = q = kmalloc_array(nqueues, sizeof(QE_t), GFP_KERNEL);
79 			list_add(&q->list, &queue->free);
83 	return queue->alloc != NULL;
87  * Function: void queue_free (Queue_t *queue)
88  * Purpose : free a queue
89  * Params  : queue - queue to free
91 void queue_free (Queue_t *queue)
93 	if (!list_empty(&queue->head))
94 		printk(KERN_WARNING "freeing non-empty queue %p\n", queue);
95 	kfree(queue->alloc);
100  * Function: int __queue_add(Queue_t *queue, struct scsi_cmnd *SCpnt, int head)
101  * Purpose : Add a new command onto a queue, adding REQUEST_SENSE to head.
102  * Params  : queue - destination queue
104  *	     head  - add command to head of queue
107 int __queue_add(Queue_t *queue, struct scsi_cmnd *SCpnt, int head)
114 	spin_lock_irqsave(&queue->queue_lock, flags);
115 	if (list_empty(&queue->free))
118 	l = queue->free.next;
128 		list_add(l, &queue->head);
130 		list_add_tail(l, &queue->head);
134 	spin_unlock_irqrestore(&queue->queue_lock, flags);
138 static struct scsi_cmnd *__queue_remove(Queue_t *queue, struct list_head *ent)
150 	list_add(ent, &queue->free);
156  * Function: struct scsi_cmnd *queue_remove_exclude (queue, exclude)
157  * Purpose : remove a SCSI command from a queue
158  * Params  : queue   - queue to remove command from
162 struct scsi_cmnd *queue_remove_exclude(Queue_t *queue, unsigned long *exclude)
168 	spin_lock_irqsave(&queue->queue_lock, flags);
169 	list_for_each(l, &queue->head) {
173 			SCpnt = __queue_remove(queue, l);
177 	spin_unlock_irqrestore(&queue->queue_lock, flags);
183  * Function: struct scsi_cmnd *queue_remove (queue)
184  * Purpose : removes first SCSI command from a queue
185  * Params  : queue   - queue to remove command from
188 struct scsi_cmnd *queue_remove(Queue_t *queue)
193 	spin_lock_irqsave(&queue->queue_lock, flags);
194 	if (!list_empty(&queue->head))
195 		SCpnt = __queue_remove(queue, queue->head.next);
196 	spin_unlock_irqrestore(&queue->queue_lock, flags);
202  * Function: struct scsi_cmnd *queue_remove_tgtluntag (queue, target, lun, tag)
203  * Purpose : remove a SCSI command from the queue for a specified target/lun/tag
204  * Params  : queue  - queue to remove command from
210 struct scsi_cmnd *queue_remove_tgtluntag(Queue_t *queue, int target, int lun,
217 	spin_lock_irqsave(&queue->queue_lock, flags);
218 	list_for_each(l, &queue->head) {
222 			SCpnt = __queue_remove(queue, l);
226 	spin_unlock_irqrestore(&queue->queue_lock, flags);
232  * Function: queue_remove_all_target(queue, target)
233  * Purpose : remove all SCSI commands from the queue for a specified target
234  * Params  : queue  - queue to remove command from
238 void queue_remove_all_target(Queue_t *queue, int target)
243 	spin_lock_irqsave(&queue->queue_lock, flags);
244 	list_for_each(l, &queue->head) {
247 			__queue_remove(queue, l);
249 	spin_unlock_irqrestore(&queue->queue_lock, flags);
253  * Function: int queue_probetgtlun (queue, target, lun)
254  * Purpose : check to see if we have a command in the queue for the specified
256  * Params  : queue  - queue to look in
261 int queue_probetgtlun (Queue_t *queue, int target, int lun)
267 	spin_lock_irqsave(&queue->queue_lock, flags);
268 	list_for_each(l, &queue->head) {
275 	spin_unlock_irqrestore(&queue->queue_lock, flags);
281  * Function: int queue_remove_cmd(Queue_t *queue, struct scsi_cmnd *SCpnt)
283  * Params  : queue - queue to look in
287 int queue_remove_cmd(Queue_t *queue, struct scsi_cmnd *SCpnt)
293 	spin_lock_irqsave(&queue->queue_lock, flags);
294 	list_for_each(l, &queue->head) {
297 			__queue_remove(queue, l);
302 	spin_unlock_irqrestore(&queue->queue_lock, flags);