From 2bd92cd2a5f96458519ed4cbbf90d9bd108edcc6 Mon Sep 17 00:00:00 2001 From: Craig Hada Date: Sun, 21 Apr 2013 23:28:18 +0000 Subject: [PATCH] be2net: enable IOMMU pass through for be2net This patch sets the coherent DMA mask to 64-bit after the be2net driver has been acknowledged that the system is 64-bit DMA capable. The coherent DMA mask is examined by the Intel IOMMU driver to determine whether to allow pass through context mapping for all devices. With this patch, the be2net driver combined with be2net compatible hardware provides comparable performance to the case where vt-d is disabled. The main use-case for this change is to decrease the time necessary to copy virtual machine memory during KVM live migration instantiations. This patch was tested on a system that enables the IOMMU in non-coherent mode. Two DMA remapper issues were encountered in the previous version and both patches have been committed. commit ea2447f700cab264019b52e2b417d689e052dcfd commit 2e12bc29fc5a12242d68e11875db3dd58efad9ff Signed-off-by: Craig Hada Signed-off-by: Sathya Perla Signed-off-by: David S. Miller --- drivers/net/ethernet/emulex/benet/be_main.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/emulex/benet/be_main.c b/drivers/net/ethernet/emulex/benet/be_main.c index e773fbaf8d02..21808680b91f 100644 --- a/drivers/net/ethernet/emulex/benet/be_main.c +++ b/drivers/net/ethernet/emulex/benet/be_main.c @@ -4134,6 +4134,11 @@ static int be_probe(struct pci_dev *pdev, const struct pci_device_id *pdev_id) status = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64)); if (!status) { + status = dma_set_coherent_mask(&pdev->dev, DMA_BIT_MASK(64)); + if (status < 0) { + dev_err(&pdev->dev, "dma_set_coherent_mask failed\n"); + goto free_netdev; + } netdev->features |= NETIF_F_HIGHDMA; } else { status = dma_set_mask(&pdev->dev, DMA_BIT_MASK(32)); -- 2.30.2