Commit f7b0c4ce authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Flush IOTLB for untrusted device in time 



By default, for performance consideration, Intel IOMMU
driver won't flush IOTLB immediately after a buffer is
unmapped. It schedules a thread and flushes IOTLB in a
batched mode. This isn't suitable for untrusted device
since it still can access the memory even if it isn't
supposed to do so.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Tested-by: default avatarXu Pengfei <pengfei.xu@intel.com>
Tested-by: default avatarMika Westerberg <mika.westerberg@intel.com>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent be068fa2

drivers/iommu/intel-iommu.c

+5 −1
Original line number Diff line number Diff line
@@ -3729,6 +3729,7 @@ static void intel_unmap(struct device *dev, dma_addr_t dev_addr, size_t size) 
	unsigned long iova_pfn;

	struct intel_iommu *iommu;

	struct page *freelist;

	struct pci_dev *pdev = NULL;



	domain = find_domain(dev);

	BUG_ON(!domain);
@@ -3741,11 +3742,14 @@ static void intel_unmap(struct device *dev, dma_addr_t dev_addr, size_t size) 
	start_pfn = mm_to_dma_pfn(iova_pfn);

	last_pfn = start_pfn + nrpages - 1;



	if (dev_is_pci(dev))

		pdev = to_pci_dev(dev);



	dev_dbg(dev, "Device unmapping: pfn %lx-%lx\n", start_pfn, last_pfn);



	freelist = domain_unmap(domain, start_pfn, last_pfn);



	if (intel_iommu_strict) {

	if (intel_iommu_strict || (pdev && pdev->untrusted)) {

		iommu_flush_iotlb_psi(iommu, domain, start_pfn,

				      nrpages, !freelist, 0);

		/* free iova */