Commit 6a62924c authored by Robin Murphy's avatar Robin Murphy Committed by Jakub Kicinski
Browse files

sfc: Stop using iommu_present() 



Even if an IOMMU might be present for some PCI segment in the system,
that doesn't necessarily mean it provides translation for the device
we care about. It appears that what we care about here is specifically
whether DMA mapping ops involve any IOMMU overhead or not, so check for
translation actually being active for our device.

Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
Acked-by: default avatarEdward Cree <ecree.xilinx@gmail.com>
Link: https://lore.kernel.org/r/7350f957944ecfce6cce90f422e3992a1f428775.1649166055.git.robin.murphy@arm.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent e9f656b7

drivers/net/ethernet/sfc/falcon/rx.c

+3 −1
Original line number Diff line number Diff line
@@ -718,12 +718,14 @@ static void ef4_init_rx_recycle_ring(struct ef4_nic *efx, 
				     struct ef4_rx_queue *rx_queue)

{

	unsigned int bufs_in_recycle_ring, page_ring_size;

	struct iommu_domain __maybe_unused *domain;



	/* Set the RX recycle ring size */

#ifdef CONFIG_PPC64

	bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;

#else

	if (iommu_present(&pci_bus_type))

	domain = iommu_get_domain_for_dev(&efx->pci_dev->dev);

	if (domain && domain->type != IOMMU_DOMAIN_IDENTITY)

		bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_IOMMU;

	else

		bufs_in_recycle_ring = EF4_RECYCLE_RING_SIZE_NOIOMMU;