Commit 61363c14 authored Feb 19, 2019 by Kuppuswamy Sathyanarayanan Committed by Joerg Roedel Feb 26, 2019

iommu/vt-d: Enable ATS only if the device uses page aligned address.

As per Intel vt-d specification, Rev 3.0 (section 7.5.1.1, title "Page
Request Descriptor"), Intel IOMMU page request descriptor only uses
bits[63:12] of the page address. Hence Intel IOMMU driver would only
permit devices that advertise they would only send Page Aligned Requests
to participate in ATS service.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Suggested-by: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

parent 8c938ddc

drivers/iommu/intel-iommu.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1408,6 +1408,7 @@ static void iommu_enable_dev_iotlb(struct device_domain_info *info)
		info->pri_enabled = 1;
		#endif
		if (!pdev->untrusted && info->ats_supported &&
		pci_ats_page_aligned(pdev) &&
		!pci_enable_ats(pdev, VTD_PAGE_SHIFT)) {
		info->ats_enabled = 1;
		domain_update_iotlb(info->domain);

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