Revert "iommu/intel-iommu: Enable CONFIG_DMA_DIRECT_OPS=y and clean up intel_{alloc,free}_coherent()"

From: Christoph Hellwig <[email protected]>

commit 7ec916f82c48dcfc115eee2e3e0e6d400e310fc5 upstream.

This commit may cause a less than required dma mask to be used for some allocations, which apparently leads to module load failures for iwlwifi sometimes.

This reverts commit d657c5c73ca987214a6f9436e435b34fc60f332a.

---
Backporting this and submitting this to stable@, because without it, ordinary WiFi is broken on a fairly vanilla Thinkpad P50, on all 4.17 kernels.

 drivers/iommu/Kconfig       |  1 -
 drivers/iommu/intel-iommu.c | 62 +++++++++++++++++++++++++++----------
 2 files changed, 46 insertions(+), 17 deletions(-)

index b38798cc5288..f3a21343e636 100644
@@ -142,7 +142,6 @@ config DMAR_TABLE
 config INTEL_IOMMU
 	bool "Support for Intel IOMMU using DMA Remapping Devices"
 	depends on PCI_MSI && ACPI && (X86 || IA64_GENERIC)
-	select DMA_DIRECT_OPS
 	select IOMMU_API
 	select IOMMU_IOVA
 	select DMAR_TABLE

2.18.0

Thanks, now queued up.

greg k-h