PCI/ATS: Handle sharing of PF PASID Capability with all VFs (2b0ae7cc) · Commits · 戴 / test

Per PCIe r5.0, sec 9.3.7.14, if a PF implements the PASID Capability, the PF PASID configuration is shared by its VFs. VFs must not implement their own PASID Capability. Since VFs don't have a PASID Capability, pci_enable_pasid() always failed, which caused IOMMU setup to fail. Update the PASID interfaces so for VFs they reflect the state of the PF PASID. [bhelgaas: rebase without pasid_cap caching, commit log] Suggested-by:

Ashok Raj <ashok.raj@intel.com> Link: https://lore.kernel.org/r/8ba1ac192e4ac737508b6ac15002158e176bab91.1567029860.git.sathyanarayanan.kuppuswamy@linux.intel.com Link: https://lore.kernel.org/r/20190905193146.90250-3-helgaas@kernel.org Signed-off-by:

Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com> Signed-off-by:

Bjorn Helgaas <bhelgaas@google.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Keith Busch <keith.busch@intel.com>

drivers/pci/ats.c

+23 −0

Original line number	Diff line number	Diff line
		@@ -346,6 +346,16 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
		u16 control, supported;
		int pos;

		/*
		* VFs must not implement the PASID Capability, but if a PF
		* supports PASID, its VFs share the PF PASID configuration.
		*/
		if (pdev->is_virtfn) {
		if (pci_physfn(pdev)->pasid_enabled)
		return 0;
		return -EINVAL;
		}

		if (WARN_ON(pdev->pasid_enabled))
		return -EBUSY;

		@@ -383,6 +393,10 @@ void pci_disable_pasid(struct pci_dev *pdev)
		u16 control = 0;
		int pos;

		/* VFs share the PF PASID configuration */
		if (pdev->is_virtfn)
		return;

		if (WARN_ON(!pdev->pasid_enabled))
		return;

		@@ -405,6 +419,9 @@ void pci_restore_pasid_state(struct pci_dev *pdev)
		u16 control;
		int pos;

		if (pdev->is_virtfn)
		return;

		if (!pdev->pasid_enabled)
		return;

		@@ -432,6 +449,9 @@ int pci_pasid_features(struct pci_dev *pdev)
		u16 supported;
		int pos;

		if (pdev->is_virtfn)
		pdev = pci_physfn(pdev);

		pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
		if (!pos)
		return -EINVAL;
		@@ -458,6 +478,9 @@ int pci_max_pasids(struct pci_dev *pdev)
		u16 supported;
		int pos;

		if (pdev->is_virtfn)
		pdev = pci_physfn(pdev);

		pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
		if (!pos)
		return -EINVAL;

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