kernel/linux.git/drivers/pci/ats.c, branch v6.3

PCI: Enable PASID only when ACS RR & UF enabled on upstream path

2022-11-03T14:47:47+00:00

The Requester ID/Process Address Space ID (PASID) combination identifies an address space distinct from the PCI bus address space, e.g., an address space defined by an IOMMU. But the PCIe fabric routes Memory Requests based on the TLP address, ignoring any PASID (PCIe r6.0, sec 2.2.10.4), so a TLP with PASID that SHOULD go upstream to the IOMMU may instead be routed as a P2P Request if its address falls in a bridge window. To ensure that all Memory Requests with PASID are routed upstream, only enable PASID if ACS P2P Request Redirect and Upstream Forwarding are enabled for the path leading to the device. Suggested-by: Jason Gunthorpe Suggested-by: Kevin Tian Signed-off-by: Lu Baolu Acked-by: Bjorn Helgaas Reviewed-by: Jason Gunthorpe Tested-by: Tony Zhu Link: https://lore.kernel.org/r/20221031005917.45690-5-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel

PCI: Allow PASID on fake PCIe devices without TLP prefixes

2021-08-26T19:21:42+00:00

Some systems, e.g., HiSilicon KunPeng920 and KunPeng930, have devices that appear as PCI but are actually on the AMBA bus. Some of these fake PCI devices support a PASID-like feature and they do have a working PASID capability even though they do not use the PCIe Transport Layer Protocol and do not support TLP prefixes. Add a pasid_no_tlp bit for this "PASID works without TLP prefixes" case and update pci_enable_pasid() so it can enable PASID on these devices. Set this bit for HiSilicon KunPeng920 and KunPeng930. [bhelgaas: squashed, commit log] Suggested-by: Bjorn Helgaas Link: https://lore.kernel.org/r/1626144876-11352-2-git-send-email-zhangfei.gao@linaro.org Link: https://lore.kernel.org/r/1626144876-11352-3-git-send-email-zhangfei.gao@linaro.org Signed-off-by: Zhangfei Gao Signed-off-by: Jean-Philippe Brucker Signed-off-by: Zhou Wang Signed-off-by: Bjorn Helgaas

PCI: Fix kernel-doc errors

2021-03-11T23:37:20+00:00

Fix kernel-doc formatting errors, function names that don't match the doc, and some missing parameter documentation. These are reported by: make W=1 drivers/pci/ No functional change intended. [bhelgaas: squashed into one patch since this only changes comments] Link: https://lore.kernel.org/r/20210311001724.423356-1-kw@linux.com Link: https://lore.kernel.org/r/20210311001724.423356-2-kw@linux.com Link: https://lore.kernel.org/r/20210311001724.423356-3-kw@linux.com Link: https://lore.kernel.org/r/20210311001724.423356-4-kw@linux.com Link: https://lore.kernel.org/r/20210311001724.423356-5-kw@linux.com Link: https://lore.kernel.org/r/20210311001724.423356-6-kw@linux.com Link: https://lore.kernel.org/r/20210311001724.423356-7-kw@linux.com Link: https://lore.kernel.org/r/20210311001724.423356-8-kw@linux.com Signed-off-by: Krzysztof Wilczyński Signed-off-by: Bjorn Helgaas

Merge branch 'pci/doc'

2020-08-05T23:24:22+00:00

- Fix several kerneldoc warnings (Krzysztof Kozlowski) * pci/doc: PCI: Fix kerneldoc warnings

PCI: Fix kerneldoc warnings

2020-08-05T23:23:14+00:00

Fix kerneldoc warnings, e.g., $ make W=1 drivers/pci/ drivers/pci/ats.c:196: warning: Function parameter or member 'pdev' not described in 'pci_enable_pri' drivers/pci/ats.c:196: warning: Function parameter or member 'reqs' not described in 'pci_enable_pri' ... Link: https://lore.kernel.org/r/20200729201224.26799-2-krzk@kernel.org Link: https://lore.kernel.org/r/20200729201224.26799-3-krzk@kernel.org Link: https://lore.kernel.org/r/20200729201224.26799-4-krzk@kernel.org Link: https://lore.kernel.org/r/20200729201224.26799-5-krzk@kernel.org Link: https://lore.kernel.org/r/20200729201224.26799-6-krzk@kernel.org Link: https://lore.kernel.org/r/20200729201224.26799-7-krzk@kernel.org Signed-off-by: Krzysztof Kozlowski Signed-off-by: Bjorn Helgaas

PCI/ATS: Add pci_pri_supported() to check device or associated PF

2020-07-24T14:50:41+00:00

For SR-IOV, the PF PRI is shared between the PF and any associated VFs, and the PRI Capability is allowed for PFs but not for VFs. Searching for the PRI Capability on a VF always fails, even if its associated PF supports PRI. Add pci_pri_supported() to check whether device or its associated PF supports PRI. [bhelgaas: commit log, avoid "!!"] Fixes: b16d0cb9e2fc ("iommu/vt-d: Always enable PASID/PRI PCI capabilities before ATS") Link: https://lore.kernel.org/r/1595543849-19692-1-git-send-email-ashok.raj@intel.com Signed-off-by: Ashok Raj Signed-off-by: Bjorn Helgaas Reviewed-by: Lu Baolu Acked-by: Joerg Roedel Cc: stable@vger.kernel.org # v4.4+

PCI/ATS: Only enable ATS for trusted devices

2020-05-27T12:35:41+00:00

Add pci_ats_supported(), which checks whether a device has an ATS capability, and whether it is trusted. A device is untrusted if it is plugged into an external-facing port such as Thunderbolt and could be spoofing an existing device to exploit weaknesses in the IOMMU configuration. PCIe ATS is one such weaknesses since it allows endpoints to cache IOMMU translations and emit transactions with 'Translated' Address Type (10b) that partially bypass the IOMMU translation. The SMMUv3 and VT-d IOMMU drivers already disallow ATS and transactions with 'Translated' Address Type for untrusted devices. Add the check to pci_enable_ats() to let other drivers (AMD IOMMU for now) benefit from it. By checking ats_cap, the pci_ats_supported() helper also returns whether ATS was globally disabled with pci=noats, and could later include more things, for example whether the whole PCIe hierarchy down to the endpoint supports ATS. Signed-off-by: Jean-Philippe Brucker Reviewed-by: Joerg Roedel Acked-by: Bjorn Helgaas Link: https://lore.kernel.org/r/20200520152201.3309416-2-jean-philippe@linaro.org Signed-off-by: Joerg Roedel

PCI/ATS: Export symbols of PASID functions

2020-03-18T21:32:25+00:00

The Arm SMMUv3 driver uses pci_{enable,disable}_pasid() and related functions. Export them to allow the driver to be built as a module. Acked-by: Bjorn Helgaas Signed-off-by: Jean-Philippe Brucker Signed-off-by: Will Deacon

Merge tag 'pci-v5.6-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

2020-02-06T14:17:38+00:00

Pull PCI fixes from Bjorn Helgaas: - Define to_pci_sysdata() always to fix build breakage when !CONFIG_PCI (Jason A. Donenfeld) - Use PF PASID for VFs to fix VF IOMMU bind failures (Kuppuswamy Sathyanarayanan) * tag 'pci-v5.6-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: PCI/ATS: Use PF PASID for VFs x86/PCI: Define to_pci_sysdata() even when !CONFIG_PCI

PCI/ATS: Use PF PASID for VFs

2020-02-05T17:58:08+00:00

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, and VFs must not implement their own PASID Capability. But commit 751035b8dc06 ("PCI/ATS: Cache PASID Capability offset") changed pci_max_pasids() and pci_pasid_features() to use the PASID Capability of the VF device instead of the associated PF device. This leads to IOMMU bind failures when pci_max_pasids() and pci_pasid_features() are called for VFs. In pci_max_pasids() and pci_pasid_features(), always use the PF PASID Capability. Fixes: 751035b8dc06 ("PCI/ATS: Cache PASID Capability offset") Link: https://lore.kernel.org/r/fe891f9755cb18349389609e7fed9940fc5b081a.1580325170.git.sathyanarayanan.kuppuswamy@linux.intel.com Signed-off-by: Kuppuswamy Sathyanarayanan Signed-off-by: Bjorn Helgaas CC: stable@vger.kernel.org # v5.5+