Commit graph

35 commits

Author SHA1 Message Date
Heiko Carstens
0f3760d43d s390: Remove unnecessary include <linux/export.h>
Remove include <linux/export.h> from all files which do not contain an
EXPORT_SYMBOL().

See commit 7d95680d64 ("scripts/misc-check: check unnecessary #include
<linux/export.h> when W=1") for more details.

Acked-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-06-17 18:18:02 +02:00
Niklas Schnelle
807c274303 s390/pci: Fix dev.dma_range_map missing sentinel element
The fixed commit sets up dev.dma_range_map but missed that this is
supposed to be an array of struct bus_dma_region with a sentinel element
with the size field set to 0 at the end. This would lead to overruns in
e.g. dma_range_map_min(). It could also result in wrong translations
instead of DMA_MAPPING_ERROR in translate_phys_to_dma() if the paddr
were to not fit in the aperture. Fix this by using the
dma_direct_set_offset() helper which creates a sentinel for us.

Fixes: d236843a69 ("s390/pci: store DMA offset in bus_dma_region")
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20250312-fix_dma_map_alloc-v2-1-530108d9de21@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-31 12:20:44 +02:00
Niklas Schnelle
8691abd3af s390/pci: Fix zpci_bus_is_isolated_vf() for non-VFs
For non-VFs, zpci_bus_is_isolated_vf() should return false because they
aren't VFs. While zpci_iov_find_parent_pf() specifically checks if
a function is a VF, it then simply returns that there is no parent. The
simplistic check for a parent then leads to these functions being
confused with isolated VFs and isolating them on their own domain even
if sibling PFs should share the domain.

Fix this by explicitly checking if a function is not a VF. Note also
that at this point the case where RIDs are ignored is already handled
and in this case all PCI functions get isolated by being detected in
zpci_bus_is_multifunction_root().

Cc: stable@vger.kernel.org
Fixes: 2844ddbd54 ("s390/pci: Fix handling of isolated VFs")
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-03-31 12:20:39 +02:00
Matthew Rosato
d236843a69 s390/pci: store DMA offset in bus_dma_region
PCI devices on s390 have a DMA offset that is reported via CLP.  In
preparation for allowing identity domains, setup the bus_dma_region
for all PCI devices using the reported CLP value.

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Tested-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20250212213418.182902-3-mjrosato@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2025-02-21 12:01:58 +01:00
Niklas Schnelle
2844ddbd54 s390/pci: Fix handling of isolated VFs
In contrast to the commit message of the fixed commit VFs whose parent
PF is not configured are not always isolated, that is put on their own
PCI domain. This is because for VFs to be added to an existing PCI
domain it is enough for that PCI domain to share the same topology ID or
PCHID. Such a matching PCI domain without a parent PF may exist when
a PF from the same PCI card created the domain with the VF being a child
of a different, non accessible, PF. While not causing technical issues
it makes the rules which VFs are isolated inconsistent.

Fix this by explicitly checking that the parent PF exists on the PCI
domain determined by the topology ID or PCHID before registering the VF.
This works because a parent PF which is under control of this Linux
instance must be enabled and configured at the point where its child VFs
appear because otherwise SR-IOV could not have been enabled on the
parent.

Fixes: 25f39d3dcb ("s390/pci: Ignore RID for isolated VFs")
Cc: stable@vger.kernel.org
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2025-02-11 19:35:08 +01:00
Niklas Schnelle
dc287e4c91 s390/pci: Fix SR-IOV for PFs initially in standby
Since commit 25f39d3dcb ("s390/pci: Ignore RID for isolated VFs") PFs
which are not initially configured but in standby are considered
isolated. That is they create only a single function PCI domain. Due to
the PCI domains being created on discovery, this means that even if they
are configured later on, sibling PFs and their child VFs will not be
added to their PCI domain breaking SR-IOV expectations.

The reason the referenced commit ignored standby PFs for the creation of
multi-function PCI subhierarchies, was to work around a PCI domain
renumbering scenario on reboot. The renumbering would occur after
removing a previously in standby PF, whose domain number is used for its
configured sibling PFs and their child VFs, but which itself remained in
standby. When this is followed by a reboot, the sibling PF is used
instead to determine the PCI domain number of it and its child VFs.

In principle it is not possible to know which standby PFs will be
configured later and which may be removed. The PCI domain and root bus
are pre-requisites for hotplug slots so the decision of which functions
belong to which domain can not be postponed. With the renumbering
occurring only in rare circumstances and being generally benign, accept
it as an oddity and fix SR-IOV for initially standby PFs simply by
allowing them to create PCI domains.

Cc: stable@vger.kernel.org
Reviewed-by: Gerd Bayer <gbayer@linux.ibm.com>
Fixes: 25f39d3dcb ("s390/pci: Ignore RID for isolated VFs")
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2025-01-26 17:24:08 +01:00
Linus Torvalds
1746db26f8 pci-v6.13-changes
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Merge tag 'pci-v6.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull PCI updates from Bjorn Helgaas:
 "Enumeration:

   - Make pci_stop_dev() and pci_destroy_dev() safe so concurrent
     callers can't stop a device multiple times, even as we migrate from
     the global pci_rescan_remove_lock to finer-grained locking (Keith
     Busch)

   - Improve pci_walk_bus() implementation by making it recursive and
     moving locking up to avoid need for a 'locked' parameter (Keith
     Busch)

   - Unexport pci_walk_bus_locked(), which is only used internally by
     the PCI core (Keith Busch)

   - Detect some Thunderbolt chips that are built-in and hence
     'trustworthy' by a heuristic since the 'ExternalFacingPort' and
     'usb4-host-interface' ACPI properties are not quite enough (Esther
     Shimanovich)

  Resource management:

   - Use PCI bus addresses (not CPU addresses) in 'ranges' properties
     when building dynamic DT nodes so systems where PCI and CPU
     addresses differ work correctly (Andrea della Porta)

   - Tidy resource sizing and assignment with helpers to reduce
     redundancy (Ilpo Järvinen)

   - Improve pdev_sort_resources() 'bogus alignment' warning to be more
     specific (Ilpo Järvinen)

  Driver binding:

   - Convert driver .remove_new() callbacks to .remove() again to finish
     the conversion from returning 'int' to being 'void' (Sergio
     Paracuellos)

   - Export pcim_request_all_regions(), a managed interface to request
     all BARs (Philipp Stanner)

   - Replace pcim_iomap_regions_request_all() with
     pcim_request_all_regions(), and pcim_iomap_table()[n] with
     pcim_iomap(n), in the following drivers: ahci, crypto qat, crypto
     octeontx2, intel_th, iwlwifi, ntb idt, serial rp2, ALSA korg1212
     (Philipp Stanner)

   - Remove the now unused pcim_iomap_regions_request_all() (Philipp
     Stanner)

   - Export pcim_iounmap_region(), a managed interface to unmap and
     release a PCI BAR (Philipp Stanner)

   - Replace pcim_iomap_regions(mask) with pcim_iomap_region(n), and
     pcim_iounmap_regions(mask) with pcim_iounmap_region(n), in the
     following drivers: fpga dfl-pci, block mtip32xx, gpio-merrifield,
     cavium (Philipp Stanner)

  Error handling:

   - Add sysfs 'reset_subordinate' to reset the entire hierarchy below a
     bridge; previously Secondary Bus Reset could only be used when
     there was a single device below a bridge (Keith Busch)

   - Warn if we reset a running device where the driver didn't register
     pci_error_handlers notification callbacks (Keith Busch)

  ASPM:

   - Disable ASPM L1 before touching L1 PM Substates to follow the spec
     closer and avoid a CPU load timeout on some platforms (Ajay
     Agarwal)

   - Set devices below Intel VMD to D0 before enabling ASPM L1 Substates
     as required per spec for all L1 Substates changes (Jian-Hong Pan)

  Power management:

   - Enable starfive controller runtime PM before probing host bridge
     (Mayank Rana)

   - Enable runtime power management for host bridges (Krishna chaitanya
     chundru)

  Power control:

   - Use of_platform_device_create() instead of of_platform_populate()
     to create pwrctl platform devices so we can control it based on the
     child nodes (Manivannan Sadhasivam)

   - Create pwrctrl platform devices only if there's a relevant power
     supply property (Manivannan Sadhasivam)

   - Add device link from the pwrctl supplier to the PCI dev to ensure
     pwrctl drivers are probed before the PCI dev driver; this avoids a
     race where pwrctl could change device power state while the PCI
     driver was active (Manivannan Sadhasivam)

   - Find pwrctl device for removal with of_find_device_by_node()
     instead of searching all children of the parent (Manivannan
     Sadhasivam)

   - Rename 'pwrctl' to 'pwrctrl' to match new bandwidth controller
     ('bwctrl') and hotplug files (Bjorn Helgaas)

  Bandwidth control:

   - Add read/modify/write locking for Link Control 2, which is used to
     manage Link speed (Ilpo Järvinen)

   - Extract Link Bandwidth Management Status check into
     pcie_lbms_seen(), where it can be shared between the bandwidth
     controller and quirks that use it to help retrain failed links
     (Ilpo Järvinen)

   - Re-add Link Bandwidth notification support with updates to address
     the reasons it was previously reverted (Alexandru Gagniuc, Ilpo
     Järvinen)

   - Add pcie_set_target_speed() and related functionality so drivers
     can manage PCIe Link speed based on thermal or other constraints
     (Ilpo Järvinen)

   - Add a thermal cooling driver to throttle PCIe Links via the
     existing thermal management framework (Ilpo Järvinen)

   - Add a userspace selftest for the PCIe bandwidth controller (Ilpo
     Järvinen)

  PCI device hotplug:

   - Add hotplug controller driver for Marvell OCTEON multi-function
     device where function 0 has a management console interface to
     enable/disable and provision various personalities for the other
     functions (Shijith Thotton)

   - Retain a reference to the pci_bus for the lifetime of a pci_slot to
     avoid a use-after-free when the thunderbolt driver resets USB4 host
     routers on boot, causing hotplug remove/add of downstream docks or
     other devices (Lukas Wunner)

   - Remove unused cpcihp struct cpci_hp_controller_ops.hardware_test
     (Guilherme Giacomo Simoes)

   - Remove unused cpqphp struct ctrl_dbg.ctrl (Christophe JAILLET)

   - Use pci_bus_read_dev_vendor_id() instead of hand-coded presence
     detection in cpqphp (Ilpo Järvinen)

   - Simplify cpqphp enumeration, which is already simple-minded and
     doesn't handle devices below hot-added bridges (Ilpo Järvinen)

  Virtualization:

   - Add ACS quirk for Wangxun FF5xxx NICs, which don't advertise an ACS
     capability but do isolate functions as though PCI_ACS_RR and
     PCI_ACS_CR were set, so the functions can be in independent IOMMU
     groups (Mengyuan Lou)

  TLP Processing Hints (TPH):

   - Add and document TLP Processing Hints (TPH) support so drivers can
     enable and disable TPH and the kernel can save/restore TPH
     configuration (Wei Huang)

   - Add TPH Steering Tag support so drivers can retrieve Steering Tag
     values associated with specific CPUs via an ACPI _DSM to improve
     performance by directing DMA writes closer to their consumers (Wei
     Huang)

  Data Object Exchange (DOE):

   - Wait up to 1 second for DOE Busy bit to clear before writing a
     request to the mailbox to avoid failures if the mailbox is still
     busy from a previous transfer (Gregory Price)

  Endpoint framework:

   - Skip attempts to allocate from endpoint controller memory window if
     the requested size is larger than the window (Damien Le Moal)

   - Add and document pci_epc_mem_map() and pci_epc_mem_unmap() to
     handle controller-specific size and alignment constraints, and add
     test cases to the endpoint test driver (Damien Le Moal)

   - Implement dwc pci_epc_ops.align_addr() so pci_epc_mem_map() can
     observe DWC-specific alignment requirements (Damien Le Moal)

   - Synchronously cancel command handler work in endpoint test before
     cleaning up DMA and BARs (Damien Le Moal)

   - Respect endpoint page size in dw_pcie_ep_align_addr() (Niklas
     Cassel)

   - Use dw_pcie_ep_align_addr() in dw_pcie_ep_raise_msi_irq() and
     dw_pcie_ep_raise_msix_irq() instead of open coding the equivalent
     (Niklas Cassel)

   - Avoid NULL dereference if Modem Host Interface Endpoint lacks
     'mmio' DT property (Zhongqiu Han)

   - Release PCI domain ID of Endpoint controller parent (not controller
     itself) and before unregistering the controller, to avoid
     use-after-free (Zijun Hu)

   - Clear secondary (not primary) EPC in pci_epc_remove_epf() when
     removing the secondary controller associated with an NTB (Zijun Hu)

  Cadence PCIe controller driver:

   - Lower severity of 'phy-names' message (Bartosz Wawrzyniak)

  Freescale i.MX6 PCIe controller driver:

   - Fix suspend/resume support on i.MX6QDL, which has a hardware
     erratum that prevents use of L2 (Stefan Eichenberger)

  Intel VMD host bridge driver:

   - Add 0xb60b and 0xb06f Device IDs for client SKUs (Nirmal Patel)

  MediaTek PCIe Gen3 controller driver:

   - Update mediatek-gen3 DT binding to require the exact number of
     clocks for each SoC (Fei Shao)

   - Add support for DT 'max-link-speed' and 'num-lanes' properties to
     restrict the link speed and width (AngeloGioacchino Del Regno)

  Microchip PolarFlare PCIe controller driver:

   - Add DT and driver support for using either of the two PolarFire
     Root Ports (Conor Dooley)

  NVIDIA Tegra194 PCIe controller driver:

   - Move endpoint controller cleanups that depend on refclk from the
     host to the notifier that tells us the host has deasserted PERST#,
     when refclk should be valid (Manivannan Sadhasivam)

  Qualcomm PCIe controller driver:

   - Add qcom SAR2130P DT binding with an additional clock (Dmitry
     Baryshkov)

   - Enable MSI interrupts if 'global' IRQ is supported, since a
     previous commit unintentionally masked them (Manivannan Sadhasivam)

   - Move endpoint controller cleanups that depend on refclk from the
     host to the notifier that tells us the host has deasserted PERST#,
     when refclk should be valid (Manivannan Sadhasivam)

   - Add DT binding and driver support for IPQ9574, with Synopsys IP
     v5.80a and Qcom IP 1.27.0 (devi priya)

   - Move the OPP "operating-points-v2" table from the
     qcom,pcie-sm8450.yaml DT binding to qcom,pcie-common.yaml, where it
     can be used by other Qcom platforms (Qiang Yu)

   - Add 'global' SPI interrupt for events like link-up, link-down to
     qcom,pcie-x1e80100 DT binding so we can start enumeration when the
     link comes up (Qiang Yu)

   - Disable ASPM L0s for qcom,pcie-x1e80100 since the PHY is not tuned
     to support this (Qiang Yu)

   - Add ops_1_21_0 for SC8280X family SoC, which doesn't use the
     'iommu-map' DT property and doesn't need BDF-to-SID translation
     (Qiang Yu)

  Rockchip PCIe controller driver:

   - Define ROCKCHIP_PCIE_AT_SIZE_ALIGN to replace magic 256 endpoint
     .align value (Damien Le Moal)

   - When unmapping an endpoint window, compute the region index instead
     of searching for it, and verify that the address was mapped (Damien
     Le Moal)

   - When mapping an endpoint window, verify that the address hasn't
     been mapped already (Damien Le Moal)

   - Implement pci_epc_ops.align_addr() for rockchip-ep (Damien Le Moal)

   - Fix MSI IRQ data mapping to observe the alignment constraint, which
     fixes intermittent page faults in memcpy_toio() and memcpy_fromio()
     (Damien Le Moal)

   - Rename rockchip_pcie_parse_ep_dt() to
     rockchip_pcie_ep_get_resources() for consistency with similar DT
     interfaces (Damien Le Moal)

   - Skip the unnecessary link train in rockchip_pcie_ep_probe() and do
     it only in the endpoint start operation (Damien Le Moal)

   - Implement pci_epc_ops.stop_link() to disable link training and
     controller configuration (Damien Le Moal)

   - Attempt link training at 5 GT/s when both partners support it
     (Damien Le Moal)

   - Add a handler for PERST# signal so we can detect host-initiated
     resets and start link training after PERST# is deasserted (Damien
     Le Moal)

  Synopsys DesignWare PCIe controller driver:

   - Clear outbound address on unmap so dw_pcie_find_index() won't match
     an ATU index that was already unmapped (Damien Le Moal)

   - Use of_property_present() instead of of_property_read_bool() when
     testing for presence of non-boolean DT properties (Rob Herring)

   - Advertise 1MB size if endpoint supports Resizable BARs, which was
     inadvertently lost in v6.11 (Niklas Cassel)

  TI J721E PCIe driver:

   - Add PCIe support for J722S SoC (Siddharth Vadapalli)

   - Delay PCIE_T_PVPERL_MS (100 ms), not just PCIE_T_PERST_CLK_US (100
     us), before deasserting PERST# to ensure power and refclk are
     stable (Siddharth Vadapalli)

  TI Keystone PCIe controller driver:

   - Set the 'ti,keystone-pcie' mode so v3.65a devices work in Root
     Complex mode (Kishon Vijay Abraham I)

   - Try to avoid unrecoverable SError for attempts to issue config
     transactions when the link is down; this is racy but the best we
     can do (Kishon Vijay Abraham I)

  Miscellaneous:

   - Reorganize kerneldoc parameter names to match order in function
     signature (Julia Lawall)

   - Fix sysfs reset_method_store() memory leak (Todd Kjos)

   - Simplify pci_create_slot() (Ilpo Järvinen)

   - Fix incorrect printf format specifiers in pcitest (Luo Yifan)"

* tag 'pci-v6.13-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (127 commits)
  PCI: rockchip-ep: Handle PERST# signal in EP mode
  PCI: rockchip-ep: Improve link training
  PCI: rockship-ep: Implement the pci_epc_ops::stop_link() operation
  PCI: rockchip-ep: Refactor endpoint link training enable
  PCI: rockchip-ep: Refactor rockchip_pcie_ep_probe() MSI-X hiding
  PCI: rockchip-ep: Refactor rockchip_pcie_ep_probe() memory allocations
  PCI: rockchip-ep: Rename rockchip_pcie_parse_ep_dt()
  PCI: rockchip-ep: Fix MSI IRQ data mapping
  PCI: rockchip-ep: Implement the pci_epc_ops::align_addr() operation
  PCI: rockchip-ep: Improve rockchip_pcie_ep_map_addr()
  PCI: rockchip-ep: Improve rockchip_pcie_ep_unmap_addr()
  PCI: rockchip-ep: Use a macro to define EP controller .align feature
  PCI: rockchip-ep: Fix address translation unit programming
  PCI/pwrctrl: Rename pwrctrl functions and structures
  PCI/pwrctrl: Rename pwrctl files to pwrctrl
  PCI/pwrctl: Remove pwrctl device without iterating over all children of pwrctl parent
  PCI/pwrctl: Ensure that pwrctl drivers are probed before PCI client drivers
  PCI/pwrctl: Create pwrctl device only if at least one power supply is present
  PCI/pwrctl: Use of_platform_device_create() to create pwrctl devices
  tools: PCI: Fix incorrect printf format specifiers
  ...
2024-11-26 18:05:44 -08:00
Ilpo Järvinen
6eaa83ec22 PCI: Remove unused PCI_SUBTRACTIVE_DECODE
2fe2abf896 ("PCI: augment bus resource table with a list") added
PCI_SUBTRACTIVE_DECODE which is put into the struct pci_bus_resource flags
field but is never read. There seems to never have been users for it.

Remove both PCI_SUBTRACTIVE_DECODE and the flags field from the struct
pci_bus_resource.

Link: https://lore.kernel.org/r/20241017141111.44612-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-10-18 13:34:59 -05:00
Niklas Schnelle
25f39d3dcb s390/pci: Ignore RID for isolated VFs
Ensure that VFs used in isolation, that is with their parent PF not
visible to the configuration but with their RID exposed, are treated
compatibly with existing isolated VF use cases without exposed RID
including RoCE Express VFs. This allows creating configurations where
one LPAR manages PFs while their child VFs are used by other LPARs. This
gives the LPAR managing the PFs a role analogous to that of the
hypervisor in a typical use case of passing child VFs to guests.

Instead of creating a multifunction struct zpci_bus whenever a PCI
function with RID exposed is discovered only create such a bus for
configured physical functions and only consider multifunction busses
when searching for an existing bus. Additionally only set zdev->devfn to
the devfn part of the RID once the function is added to a multifunction
bus.

This also fixes probing of more than 7 such isolated VFs from the same
physical bus. This is because common PCI code in pci_scan_slot() only
looks for more functions when pdev->multifunction is set which somewhat
counter intutively is not the case for VFs.

Note that PFs are looked at before their child VFs is guaranteed because
we sort the zpci_list by RID ascending.

Reviewed-by: Gerd Bayer <gbayer@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-10 15:32:43 +02:00
Niklas Schnelle
126034faaa s390/pci: Use topology ID for multi-function devices
The newly introduced topology ID (TID) field in the CLP Query PCI
Function explicitly identifies groups of PCI functions whose RIDs belong
to the same (sub-)topology. When available use the TID instead of the
PCHID to match zPCI busses/domains for multi-function devices. Note that
currently only a single PCI bus per TID is supported. This change is
required because in future machines the PCHID will not identify a PCI
card but a specific port in the case of some multi-port NICs while from
a PCI point of view the entire card is a subtopology.

Reviewed-by: Gerd Bayer <gbayer@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-10-10 15:32:43 +02:00
Niklas Schnelle
c76c067e48 s390/pci: Use dma-iommu layer
While s390 already has a standard IOMMU driver and previous changes have
added I/O TLB flushing operations this driver is currently only used for
user-space PCI access such as vfio-pci. For the DMA API s390 instead
utilizes its own implementation in arch/s390/pci/pci_dma.c which drives
the same hardware and shares some code but requires a complex and
fragile hand over between DMA API and IOMMU API use of a device and
despite code sharing still leads to significant duplication and
maintenance effort. Let's utilize the common code DMAP API
implementation from drivers/iommu/dma-iommu.c instead allowing us to
get rid of arch/s390/pci/pci_dma.c.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20230928-dma_iommu-v13-3-9e5fc4dacc36@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-10-02 08:43:00 +02:00
Vasily Gorbik
f62f8b716d Merge branch 'uaccess-inline-asm-cleanup' into features
Heiko Carstens says:

===================
There are a couple of oddities within the s390 uaccess library
functions. Therefore cleanup the whole uaccess.c file.

There is no functional change, only improved readability. The output
of "objdump -Dr" was always compared before/after each patch to make
sure that the generated object file is identical, if that could be
expected. Therefore the series also includes more patches than really
required to cleanup the code.

Furthermore the kunit usercopy tests also still pass.
===================

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-04-04 18:29:28 +02:00
Niklas Schnelle
45e5f0c017 s390/pci: clean up left over special treatment for function zero
Prior to commit 960ac36264 ("s390/pci: allow zPCI zbus without
a function zero") enabling and scanning a PCI function had to
potentially be postponed until the function with devfn zero on that bus
was plugged. While the commit removed the waiting itself extra code to
scan all functions on the PCI bus once function zero appeared was
missed. Remove that code and the outdated comments about waiting for
function zero.

Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20230306151014.60913-5-schnelle@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-03-13 09:16:43 +01:00
Niklas Schnelle
b881208dcd s390/pci: remove redundant pci_bus_add_devices() on new bus
The pci_bus_add_devices() call in zpci_bus_create_pci_bus() is without
function since at this point no device could have been added to the
freshly created PCI bus.

Suggested-by: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20230306151014.60913-4-schnelle@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-03-13 09:16:43 +01:00
Niklas Schnelle
ae83707f39 s390/pci: only add specific device in zpci_bus_scan_device()
As the name suggests zpci_bus_scan_device() is used to scan a specific
device and thus pci_bus_add_device() for that device is sufficient.
Furthermore move this call inside the rescan/remove locking.

Suggested-by: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20230306151014.60913-3-schnelle@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-03-13 09:16:43 +01:00
Niklas Schnelle
ab90950985 PCI: s390: Fix use-after-free of PCI resources with per-function hotplug
On s390 PCI functions may be hotplugged individually even when they
belong to a multi-function device. In particular on an SR-IOV device VFs
may be removed and later re-added.

In commit a50297cf82 ("s390/pci: separate zbus creation from
scanning") it was missed however that struct pci_bus and struct
zpci_bus's resource list retained a reference to the PCI functions MMIO
resources even though those resources are released and freed on
hot-unplug. These stale resources may subsequently be claimed when the
PCI function re-appears resulting in use-after-free.

One idea of fixing this use-after-free in s390 specific code that was
investigated was to simply keep resources around from the moment a PCI
function first appeared until the whole virtual PCI bus created for
a multi-function device disappears. The problem with this however is
that due to the requirement of artificial MMIO addreesses (address
cookies) extra logic is then needed to keep the address cookies
compatible on re-plug. At the same time the MMIO resources semantically
belong to the PCI function so tying their lifecycle to the function
seems more logical.

Instead a simpler approach is to remove the resources of an individually
hot-unplugged PCI function from the PCI bus's resource list while
keeping the resources of other PCI functions on the PCI bus untouched.

This is done by introducing pci_bus_remove_resource() to remove an
individual resource. Similarly the resource also needs to be removed
from the struct zpci_bus's resource list. It turns out however, that
there is really no need to add the MMIO resources to the struct
zpci_bus's resource list at all and instead we can simply use the
zpci_bar_struct's resource pointer directly.

Fixes: a50297cf82 ("s390/pci: separate zbus creation from scanning")
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20230306151014.60913-2-schnelle@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-03-13 09:15:11 +01:00
Niklas Schnelle
960ac36264 s390/pci: allow zPCI zbus without a function zero
Currently the zPCI code blocks PCI bus creation and probing of a zPCI zbus
unless there is a PCI function with devfn 0. This is always the case for
the PCI functions with hidden RID, but may keep PCI functions from a
multi-function PCI device with RID information invisible until the function
0 becomes visible. Worse, as a PCI bus is necessary to even present a PCI
hotplug slot, even that remains invisible.

With the probing of these so-called isolated PCI functions enabled for s390
in common code, this restriction is no longer necessary. On network cards
with multiple ports and a PF per port this also allows using each port on
its own while still providing the physical PCI topology information in the
devfn needed to associate VFs with their parent PF.

Link: https://lore.kernel.org/r/20220628143100.3228092-6-schnelle@linux.ibm.com
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
2022-07-22 16:06:13 -05:00
Niklas Schnelle
1f3f76812d s390/pci: improve DMA translation init and exit
Currently zpci_dma_init_device()/zpci_dma_exit_device() is called as
part of zpci_enable_device()/zpci_disable_device() and errors for
zpci_dma_exit_device() are always ignored even if we could abort.

Improve upon this by moving zpci_dma_exit_device() out of
zpci_disable_device() and check for errors whenever we have a way to
abort the current operation. Note that for example in
zpci_event_hard_deconfigured() the device is expected to be gone so we
really can't abort and proceed even in case of error.

Similarly move the cc == 3 special case out of zpci_unregister_ioat()
and into the callers allowing to abort when finding an already disabled
devices precludes proceeding with the operation.

While we are at it log IOAT register/unregister errors in the s390
debugfs log,

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-08-25 11:03:34 +02:00
Niklas Schnelle
81a076171e s390/pci: reset zdev->zbus on registration failure
On failure to register a struct zpci_dev with a struct zpci_bus we left
a dangling pointer in zdev->zbus. As zpci_create_device() bails if
zpci_bus_device_register() fails this is of no consequence but still bad
practice.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-08-25 11:03:32 +02:00
Niklas Schnelle
14c87ba812 s390/pci: separate zbus registration from scanning
Now that the zbus can be created without being scanned we can go one
step further and make registering a device to a zbus independent from
scanning it. This way the zbus handling becomes much more natural
in that functions can be registered on the zbus to be scanned later more
closely resembling the handling of both real PCI hardware and other
virtual PCI busses like Hyper-V's virtual PCI bus (see for example
drivers/pci/controller/pci-hyperv.c:create_root_hv_pci_bus()).

Having zbus registration separate from scanning allows us to return
fully initialized but still disabled zdevs from zpci_create_device()
which can then be configured just as we would configure a zdev from
standby (minus the SCLP Configure already done by the platform).  There
is still the exception that a PCI function with non-zero devfn can be
plugged before its PCI bus, which depends on the function with zero
devfn, is created. In this case the zdev returend from
zpci_create_device() is still missing its bus, hotplug slot, and
resources which need to be created later but at least it doesn't wait in
the enabled state and can otherwise be treated as initialized.

With this we also separate the initial PCI scan using CLP List PCI
Functions into two phases. In the CLP loop's callback we only register
each function with a virtual zbus creating the latter as needed. Then,
after we have built this virtual PCI topology based on our list of
zbusses, we can make use of the common code functionality to scan each
complete zbus as a separate child bus.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-04-12 12:46:42 +02:00
Niklas Schnelle
0350276168 s390/pci: use mutex not spinlock for zbus list
In a later change we will first collect all PCI functions from the CLP
List PCI functions call, then register them to/creating the relevant
zbus. Then only after we've created our virtual bus structure will we
scan all zbusses iterating over the zbus list. Since scanning is
relatively slow a spinlock is a bad fit for protecting the
loop over the devices on the zbus. Furthermore doing the probing on the
bus we need to use pci_lock_rescan_remove() as devices are added to
the PCI subsystem and that is a mutex which can't be locked nested
inside a spinlock section. Note that the contention of this lock should
be very low either way as zbusses are only added/removed concurrently on
hotplug events.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-04-12 12:46:42 +02:00
Niklas Schnelle
a50297cf82 s390/pci: separate zbus creation from scanning
In the existing code the creation of the PCI bus and the scanning of
function zero all happens in zpci_scan_bus(). This in turn requires
functions to be enabled and their resources to be available before the
PCI bus is even created.

This not only means that functions are enabled long before they are
actually made available to the common PCI subsystem. In case of
functions with non-zero devfn which appeared before the function with
devfn zero they can wait arbitrarily long in this enabled but not
scanned state.

Fix this by separating the creation of the PCI bus from scanning it and
only prepare, that is enable and setup MMIO bus resources, functions
just before they are scanned. As they may be scanned multiple times
track if we already created resources in the zdev.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-04-12 12:46:42 +02:00
Niklas Schnelle
7dc697d6b2 s390/pci: do more bus setup in zpci_bus_scan()
Pull setting the maximum bus speed and multifunction attribute into
zpci_bus_scan() in preparation for handling bus creation separately
from scanning the bus.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-04-12 12:46:41 +02:00
Niklas Schnelle
faf29a4d93 s390/pci: introduce zpci_bus_scan_device()
To match zpci_bus_scan_device() and the PCI common code terminology and
to remove some code duplication, we pull the multiple uses of
pci_scan_single_device() into a function. For now this has the side
effect of adding each device to the PCI bus separately and locking and
unlocking the rescan/remove lock for each instead of just once per bus.
This is clearly less efficient but provides a correct intermediate
behavior until a follow on change does both the adding and scanning only
once per bus.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-04-12 12:46:41 +02:00
Niklas Schnelle
95b3a8b401 s390/pci: move zpci_remove_device() to bus code
The zpci_remove_device() function removes the device from the PCI common
code core which is an operation dealing primarily with the zbus and PCI
bus code. With that and to match an upcoming refactoring of the
symmetric scanning part move it to the bus code.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-03-22 11:36:04 +01:00
Linus Torvalds
fc996db970 VFIO updates for v5.10-rc1
- New fsl-mc vfio bus driver supporting userspace drivers of objects
    within NXP's DPAA2 architecture (Diana Craciun)
 
  - Support for exposing zPCI information on s390 (Matthew Rosato)
 
  - Fixes for "detached" VFs on s390 (Matthew Rosato)
 
  - Fixes for pin-pages and dma-rw accesses (Yan Zhao)
 
  - Cleanups and optimize vconfig regen (Zenghui Yu)
 
  - Fix duplicate irq-bypass token registration (Alex Williamson)
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Merge tag 'vfio-v5.10-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - New fsl-mc vfio bus driver supporting userspace drivers of objects
   within NXP's DPAA2 architecture (Diana Craciun)

 - Support for exposing zPCI information on s390 (Matthew Rosato)

 - Fixes for "detached" VFs on s390 (Matthew Rosato)

 - Fixes for pin-pages and dma-rw accesses (Yan Zhao)

 - Cleanups and optimize vconfig regen (Zenghui Yu)

 - Fix duplicate irq-bypass token registration (Alex Williamson)

* tag 'vfio-v5.10-rc1' of git://github.com/awilliam/linux-vfio: (30 commits)
  vfio iommu type1: Fix memory leak in vfio_iommu_type1_pin_pages
  vfio/pci: Clear token on bypass registration failure
  vfio/fsl-mc: fix the return of the uninitialized variable ret
  vfio/fsl-mc: Fix the dead code in vfio_fsl_mc_set_irq_trigger
  vfio/fsl-mc: Fixed vfio-fsl-mc driver compilation on 32 bit
  MAINTAINERS: Add entry for s390 vfio-pci
  vfio-pci/zdev: Add zPCI capabilities to VFIO_DEVICE_GET_INFO
  vfio/fsl-mc: Add support for device reset
  vfio/fsl-mc: Add read/write support for fsl-mc devices
  vfio/fsl-mc: trigger an interrupt via eventfd
  vfio/fsl-mc: Add irq infrastructure for fsl-mc devices
  vfio/fsl-mc: Added lock support in preparation for interrupt handling
  vfio/fsl-mc: Allow userspace to MMAP fsl-mc device MMIO regions
  vfio/fsl-mc: Implement VFIO_DEVICE_GET_REGION_INFO ioctl call
  vfio/fsl-mc: Implement VFIO_DEVICE_GET_INFO ioctl
  vfio/fsl-mc: Scan DPRC objects on vfio-fsl-mc driver bind
  vfio: Introduce capability definitions for VFIO_DEVICE_GET_INFO
  s390/pci: track whether util_str is valid in the zpci_dev
  s390/pci: stash version in the zpci_dev
  vfio/fsl-mc: Add VFIO framework skeleton for fsl-mc devices
  ...
2020-10-22 13:00:44 -07:00
Matthew Rosato
08b6e22b85 s390/pci: Mark all VFs as not implementing PCI_COMMAND_MEMORY
For s390 we can have VFs that are passed-through without the associated
PF. Firmware provides an emulation layer to allow these devices to
operate independently, but is missing emulation of the Memory Space
Enable bit.  For these as well as linked VFs, set no_command_memory
which specifies these devices do not implement PCI_COMMAND_MEMORY.

Fixes: abafbc551f ("vfio-pci: Invalidate mmaps and block MMIO access on disabled memory")
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-09-22 10:52:00 -06:00
Niklas Schnelle
abb95b7550 s390/pci: consolidate SR-IOV specific code
currently we have multiple #ifdef CONFIG_PCI_IOV blocks spread over
different compliation units and headers, all dealing with SR-IOV
specific behavior.
This violates the style guide which discourages conditionally compiled
code blocks and hinders maintainability by speading SR-IOV functionality
over many files.

Let's move all of this into a conditionally compiled pci_iov.c file and
local header and prefix SR-IOV specific functions with zpci_iov_*.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-09-14 11:38:34 +02:00
Niklas Schnelle
b97bf44f99 s390/pci: fix PF/VF linking on hot plug
Currently there are four places in which a PCI function is scanned
and made available to drivers:
 1. In pci_scan_root_bus() as part of the initial zbus
    creation.
 2. In zpci_bus_add_devices() when registering
    a device in configured state on a zbus that has already been
    scanned.
 3. When a function is already known to zPCI (in reserved/standby state)
    and configuration is triggered through firmware by PEC 0x301.
 4. When a device is already known to zPCI (in standby/reserved state)
    and configuration is triggered from within Linux using
    enable_slot().

The PF/VF linking step and setting of pdev->is_virtfn introduced with
commit e5794cf1a2 ("s390/pci: create links between PFs and VFs") was
only triggered for the second case, which is where VFs created through
sriov_numvfs usually land. However unlike some other platforms but like
POWER VFs can be individually enabled/disabled through
/sys/bus/pci/slots.

Fix this by doing VF setup as part of pcibios_bus_add_device() which is
called in all of the above cases.

Finally to remove the PF/VF links call the common code
pci_iov_remove_virtfn() function to remove linked VFs.
This takes care of the necessary sysfs cleanup.

Fixes: e5794cf1a2 ("s390/pci: create links between PFs and VFs")
Cc: <stable@vger.kernel.org> # 5.8: 2f0230b2f2: s390/pci: re-introduce zpci_remove_device()
Cc: <stable@vger.kernel.org> # 5.8
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-08-17 13:17:34 +02:00
Niklas Schnelle
3cddb79afc s390/pci: fix zpci_bus_link_virtfn()
We were missing the pci_dev_put() for candidate PFs.  Furhtermore in
discussion with upstream it turns out that somewhat counterintuitively
some common code, in particular the vfio-pci driver, assumes that
pdev->is_virtfn always implies that pdev->physfn is set, i.e. that VFs
are always linked.
While POWER does seem to set pdev->is_virtfn even for unlinked functions
(see comments in arch/powerpc/kernel/eeh.c:eeh_debugfs_break_device())
for now just be safe and only set pdev->is_virtfn on linking.
Also make sure that we only search for parent PFs if the zbus is
multifunction and we thus know the devfn values supplied by firmware
come from the RID.

Fixes: e5794cf1a2 ("s390/pci: create links between PFs and VFs")
Cc: <stable@vger.kernel.org> # 5.8
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-08-17 13:17:18 +02:00
Niklas Schnelle
e5794cf1a2 s390/pci: create links between PFs and VFs
On s390 PCI Virtual Functions (VFs) are scanned by firmware and are made
available to Linux via the hot-plug interface. As such the common code
path of doing the scan directly using the parent Physical Function (PF)
is not used and fenced off with the no_vf_scan attribute.

Even if the partition created the VFs itself e.g. using the sriov_numvfs
attribute of a PF, the PF/VF links thus need to be established after the
fact. To do this when a VF is plugged we scan through all functions on
the same zbus and test whether they are the parent PF in which case we
establish the necessary links.

With these links established there is now no more need to fence off
pci_iov_remove_virtfn() for pdev->no_vf_scan as the common code now
works fine.

Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Link: https://lore.kernel.org/r/20200506154139.90609-3-schnelle@linux.ibm.com
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-20 10:22:51 +02:00
Pierre Morel
d1379279f2 s390/pci: removes wrong PCI multifunction assignment
The assignment of the PCI device multifunction attribute
is set during the PCI device probe.
There is no need to set it here.

Let's do it right and remove this assignment.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-05-06 14:59:20 +02:00
Pierre Morel
44510d6fa0 s390/pci: Handling multifunctions
We allow multiple functions on a single bus.
We suppress the ZPCI_DEVFN definition and replace its
occurences with zpci->devfn.

We verify the number of device during the registration.

There can never be more domains in use than existing
devices, so we do not need to verify the count of domain
after having verified the count of devices.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 13:49:47 +02:00
Pierre Morel
65e450a9f9 s390/pci: Adding bus resource
The current PCI implementation do not provide a bus resource.
This leads to a notice being print at boot.
Let's do it more nicely and provide the bus resource.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 13:49:46 +02:00
Pierre Morel
05bc1be6db s390/pci: create zPCI bus
The zPCI bus is in charge to handle common zPCI resources for
zPCI devices.

Creating the zPCI bus, the PCI bus, the zPCI devices and the
PCI devices and hotplug slots
done in a specific order:
- PCI hotplug slot creation needs a PCI bus
- PCI bus needs a PCI domain
  which is reported by the pci_domain_nr() when setting up the
  host bridge
- PCI domain is set from the zPCI with devfn 0
  this is necessary to have a reproducible enumeration

Therefore we can not create devices or hotplug slots for any PCI
device associated with a zPCI device before having discovered
the function zero of the bus.

The discovery and initialization of devices can be done at several
points in the code:
- On Events, serialized in a thread context
- On initialization, in the kernel init thread context
- When powering on the hotplug slot, in a user thread context

The removal of devices and their parent bus may also be done on
events or for devices when powering down the slot.

To guarantee the existence of the bus and devices until they are
no more needed we use kref in zPCI bus and introduce a reference
count in the zPCI devices.

In this patch the zPCI bus still only accept a device with
a devfn 0.

Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-04-28 13:49:46 +02:00