static inline struct fiops_ioc *fiops_cic_lookup(struct fiops_data *fiopsd,
					       struct io_context *ioc)
{
	if (ioc)
		return icq_to_cic(ioc_lookup_icq(ioc, fiopsd->queue));
	return NULL;
}
/**
 * bfq_bic_lookup - search into @ioc a bic associated to @bfqd.
 * @bfqd: the lookup key.
 * @ioc: the io_context of the process doing I/O.
 *
 * Queue lock must be held.
 */
static inline struct bfq_io_cq *bfq_bic_lookup(struct bfq_data *bfqd,
                                               struct io_context *ioc)
{
        if(ioc)
                return icq_to_bic(ioc_lookup_icq(ioc, bfqd->queue));
        return NULL;
}
예제 #3
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/**
 * ioc_create_icq - create and link io_cq
 * @q: request_queue of interest
 * @gfp_mask: allocation mask
 *
 * Make sure io_cq linking %current->io_context and @q exists.  If either
 * io_context and/or icq don't exist, they will be created using @gfp_mask.
 *
 * The caller is responsible for ensuring @ioc won't go away and @q is
 * alive and will stay alive until this function returns.
 */
struct io_cq *ioc_create_icq(struct request_queue *q, gfp_t gfp_mask)
{
	struct elevator_type *et = q->elevator->type;
	struct io_context *ioc;
	struct io_cq *icq;

	/* allocate stuff */
	ioc = create_io_context(current, gfp_mask, q->node);
	if (!ioc)
		return NULL;

	icq = kmem_cache_alloc_node(et->icq_cache, gfp_mask | __GFP_ZERO,
				    q->node);
	if (!icq)
		return NULL;

	if (radix_tree_preload(gfp_mask) < 0) {
		kmem_cache_free(et->icq_cache, icq);
		return NULL;
	}

	icq->ioc = ioc;
	icq->q = q;
	INIT_LIST_HEAD(&icq->q_node);
	INIT_HLIST_NODE(&icq->ioc_node);

	/* lock both q and ioc and try to link @icq */
	spin_lock_irq(q->queue_lock);
	spin_lock(&ioc->lock);

	if (likely(!radix_tree_insert(&ioc->icq_tree, q->id, icq))) {
		hlist_add_head(&icq->ioc_node, &ioc->icq_list);
		list_add(&icq->q_node, &q->icq_list);
		if (et->ops.elevator_init_icq_fn)
			et->ops.elevator_init_icq_fn(icq);
	} else {
		kmem_cache_free(et->icq_cache, icq);
		icq = ioc_lookup_icq(ioc, q);
		if (!icq)
			printk(KERN_ERR "cfq: icq link failed!\n");
	}

	spin_unlock(&ioc->lock);
	spin_unlock_irq(q->queue_lock);
	radix_tree_preload_end();
	return icq;
}