* Different hardware can have different requirements as to what pages
* it can do I/O directly to. A low level driver can call
* blk_queue_bounce_limit to have lower memory pages allocated as bounce
- * buffers for doing I/O to pages residing above @page. By default
- * the block layer sets this to the highest numbered "low" memory page.
+ * buffers for doing I/O to pages residing above @page.
**/
void blk_queue_bounce_limit(request_queue_t *q, u64 dma_addr)
{
unsigned long bounce_pfn = dma_addr >> PAGE_SHIFT;
-
- /*
- * set appropriate bounce gfp mask -- unfortunately we don't have a
- * full 4GB zone, so we have to resort to low memory for any bounces.
- * ISA has its own < 16MB zone.
- */
- if (bounce_pfn < blk_max_low_pfn) {
- BUG_ON(dma_addr < BLK_BOUNCE_ISA);
+ int dma = 0;
+
+ q->bounce_gfp = GFP_NOIO;
+#if BITS_PER_LONG == 64
+ /* Assume anything <= 4GB can be handled by IOMMU.
+ Actually some IOMMUs can handle everything, but I don't
+ know of a way to test this here. */
+ if (bounce_pfn < (0xffffffff>>PAGE_SHIFT))
+ dma = 1;
+ q->bounce_pfn = max_low_pfn;
+#else
+ if (bounce_pfn < blk_max_low_pfn)
+ dma = 1;
+ q->bounce_pfn = bounce_pfn;
+#endif
+ if (dma) {
init_emergency_isa_pool();
q->bounce_gfp = GFP_NOIO | GFP_DMA;
- } else
- q->bounce_gfp = GFP_NOIO;
-
- q->bounce_pfn = bounce_pfn;
+ q->bounce_pfn = bounce_pfn;
+ }
}
EXPORT_SYMBOL(blk_queue_bounce_limit);
return NULL;
q->node = node_id;
- if (blk_init_free_list(q))
- goto out_init;
+ if (blk_init_free_list(q)) {
+ kmem_cache_free(requestq_cachep, q);
+ return NULL;
+ }
/*
* if caller didn't supply a lock, they get per-queue locking with
return q;
}
- blk_cleanup_queue(q);
-out_init:
- kmem_cache_free(requestq_cachep, q);
+ blk_put_queue(q);
return NULL;
}
EXPORT_SYMBOL(blk_init_queue_node);
queue_requests_store(struct request_queue *q, const char *page, size_t count)
{
struct request_list *rl = &q->rq;
+ unsigned long nr;
+ int ret = queue_var_store(&nr, page, count);
+ if (nr < BLKDEV_MIN_RQ)
+ nr = BLKDEV_MIN_RQ;
- int ret = queue_var_store(&q->nr_requests, page, count);
- if (q->nr_requests < BLKDEV_MIN_RQ)
- q->nr_requests = BLKDEV_MIN_RQ;
+ spin_lock_irq(q->queue_lock);
+ q->nr_requests = nr;
blk_queue_congestion_threshold(q);
if (rl->count[READ] >= queue_congestion_on_threshold(q))
blk_clear_queue_full(q, WRITE);
wake_up(&rl->wait[WRITE]);
}
+ spin_unlock_irq(q->queue_lock);
return ret;
}