iommu/amd: Implement flush queue
With the flush queue the IOMMU TLBs will not be flushed at
every dma-ops unmap operation. The unmapped ranges will be
queued and flushed at once, when the queue is full. This
makes unmapping operations a lot faster (on average) and
restores the performance of the old address allocator.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 0884b12..a8e4c5a 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -2120,6 +2120,66 @@
*
*****************************************************************************/
+static void __queue_flush(struct flush_queue *queue)
+{
+ struct protection_domain *domain;
+ unsigned long flags;
+ int idx;
+
+ /* First flush TLB of all known domains */
+ spin_lock_irqsave(&amd_iommu_pd_lock, flags);
+ list_for_each_entry(domain, &amd_iommu_pd_list, list)
+ domain_flush_tlb(domain);
+ spin_unlock_irqrestore(&amd_iommu_pd_lock, flags);
+
+ /* Wait until flushes have completed */
+ domain_flush_complete(NULL);
+
+ for (idx = 0; idx < queue->next; ++idx) {
+ struct flush_queue_entry *entry;
+
+ entry = queue->entries + idx;
+
+ free_iova_fast(&entry->dma_dom->iovad,
+ entry->iova_pfn,
+ entry->pages);
+
+ /* Not really necessary, just to make sure we catch any bugs */
+ entry->dma_dom = NULL;
+ }
+
+ queue->next = 0;
+}
+
+static void queue_add(struct dma_ops_domain *dma_dom,
+ unsigned long address, unsigned long pages)
+{
+ struct flush_queue_entry *entry;
+ struct flush_queue *queue;
+ unsigned long flags;
+ int idx;
+
+ pages = __roundup_pow_of_two(pages);
+ address >>= PAGE_SHIFT;
+
+ queue = get_cpu_ptr(&flush_queue);
+ spin_lock_irqsave(&queue->lock, flags);
+
+ if (queue->next == FLUSH_QUEUE_SIZE)
+ __queue_flush(queue);
+
+ idx = queue->next++;
+ entry = queue->entries + idx;
+
+ entry->iova_pfn = address;
+ entry->pages = pages;
+ entry->dma_dom = dma_dom;
+
+ spin_unlock_irqrestore(&queue->lock, flags);
+ put_cpu_ptr(&flush_queue);
+}
+
+
/*
* In the dma_ops path we only have the struct device. This function
* finds the corresponding IOMMU, the protection domain and the
@@ -2258,10 +2318,13 @@
start += PAGE_SIZE;
}
- domain_flush_tlb(&dma_dom->domain);
- domain_flush_complete(&dma_dom->domain);
-
- dma_ops_free_iova(dma_dom, dma_addr, pages);
+ if (amd_iommu_unmap_flush) {
+ dma_ops_free_iova(dma_dom, dma_addr, pages);
+ domain_flush_tlb(&dma_dom->domain);
+ domain_flush_complete(&dma_dom->domain);
+ } else {
+ queue_add(dma_dom, dma_addr, pages);
+ }
}
/*