PCI/ATS: Handle sharing of PF PRI Capability with all VFs (9bf49e36) · Commits · 戴 / test

Per PCIe r5.0, sec 9.3.7.11, VFs must not implement the PRI Capability. If the PF implements PRI, it is shared by the VFs. Since VFs don't have a PRI Capability, pci_enable_pri() always failed, which caused IOMMU setup to fail. Update the PRI interfaces so for VFs they reflect the state of the PF PRI. [bhelgaas: rebase without pri_cap caching, commit log] Suggested-by:

Ashok Raj <ashok.raj@intel.com> Link: https://lore.kernel.org/r/b971e31f8695980da8e4a7f93e3b6a3edba3edaa.1567029860.git.sathyanarayanan.kuppuswamy@linux.intel.com Link: https://lore.kernel.org/r/20190905193146.90250-2-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

+24 −0

Original line number	Diff line number	Diff line
		@@ -182,6 +182,17 @@ int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
		u32 max_requests;
		int pos;

		/*
		* VFs must not implement the PRI Capability. If their PF
		* implements PRI, it is shared by the VFs, so if the PF PRI is
		* enabled, it is also enabled for the VF.
		*/
		if (pdev->is_virtfn) {
		if (pci_physfn(pdev)->pri_enabled)
		return 0;
		return -EINVAL;
		}

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

		@@ -218,6 +229,10 @@ void pci_disable_pri(struct pci_dev *pdev)
		u16 control;
		int pos;

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

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

		@@ -243,6 +258,9 @@ void pci_restore_pri_state(struct pci_dev *pdev)
		u32 reqs = pdev->pri_reqs_alloc;
		int pos;

		if (pdev->is_virtfn)
		return;

		if (!pdev->pri_enabled)
		return;

		@@ -267,6 +285,9 @@ int pci_reset_pri(struct pci_dev *pdev)
		u16 control;
		int pos;

		if (pdev->is_virtfn)
		return 0;

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

		@@ -293,6 +314,9 @@ int pci_prg_resp_pasid_required(struct pci_dev *pdev)
		u16 status;
		int pos;

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

		pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
		if (!pos)
		return 0;

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