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There's a number of tasks that need the state of a zpci device
to be stable. Other tasks need to be synchronized as they change the state.
State changes could be generated by the system as availability or error
events, or be requested by the user through manipulations in sysfs.
Some other actions accessible through sysfs - like device resets - need the
state to be stable.
Unsynchronized state handling could lead to unusable devices. This has
been observed in cases of concurrent state changes through systemd udev
rules and DPM boot control. Some breakage can be provoked by artificial
tests, e.g. through repetitively injecting "recover" on a PCI function
through sysfs while running a "hotplug remove/add" in a loop through a
PCI slot's "power" attribute in sysfs. After a few iterations this could
result in a kernel oops.
So introduce a new mutex "state_lock" to guard the state property of the
struct zpci_dev. Acquire this lock in all task that modify the state:
- hotplug add and remove, through the PCI hotplug slot entry,
- avaiability events, as reported by the platform,
- error events, as reported by the platform,
- during device resets, explicit through sysfs requests or
implict through the common PCI layer.
Break out an inner _do_recover() routine out of recover_store() to
separte the necessary synchronizations from the actual manipulations of
the zpci_dev required for the reset.
With the following changes I was able to run the inject loops for hours
without hitting an error.
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
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Since this guards only the Function Measurement Block, rename from
generic lock to fmb_lock in preparation to introduce another lock
that guards the state member
Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
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Together with enabling the Function Measurement Block
zpci_fmb_enable_device() also resets the software counters. This allows
to use "echo 0 > /sys/kernel/debug/pci/<dev>/statistics" followed by
echo "1 > /../statistics" to reset all counters. In commit c76c067e488c
("s390/pci: Use dma-iommu layer") this use of the now obsolete counters
in struct zpci_device was missed as was their removal. Fix this by
resetting the new counters and removing the old ones.
Fixes: c76c067e488c ("s390/pci: Use dma-iommu layer")
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20231004-dma_iommu_fix-v1-1-129777cd8232@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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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>
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I/O translation tables on s390 use 8 byte page table entries and tables
which are allocated lazily but only freed when the entire I/O
translation table is torn down. Also each IOVA can at any time only
translate to one physical address Furthermore I/O table accesses by the
IOMMU hardware are cache coherent. With a bit of care we can thus use
atomic updates to manipulate the translation table without having to use
a global lock at all. This is done analogous to the existing I/O
translation table handling code used on Intel and AMD x86 systems.
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20221109142903.4080275-6-schnelle@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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The s390_domain->devices list is only added to when new devices are
attached but is iterated through in read-only fashion for every mapping
operation as well as for I/O TLB flushes and thus in performance
critical code causing contention on the s390_domain->list_lock.
Fortunately such a read-mostly linked list is a standard use case for
RCU. This change closely follows the example fpr RCU protected list
given in Documentation/RCU/listRCU.rst.
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20221109142903.4080275-4-schnelle@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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If a zPCI device is in the error state while switching IOMMU domains
zpci_register_ioat() will fail and we would end up with the device not
attached to any domain. In this state since zdev->dma_table == NULL
a reset via zpci_hot_reset_device() would wrongfully re-initialize the
device for DMA API usage using zpci_dma_init_device(). As automatic
recovery is currently disabled while attached to an IOMMU domain this
only affects slot resets triggered through other means but will affect
automatic recovery once we switch to using dma-iommu.
Additionally with that switch common code expects attaching to the
default domain to always work so zpci_register_ioat() should only fail
if there is no chance to recover anyway, e.g. if the device has been
unplugged.
Improve the robustness of attach by specifically looking at the status
returned by zpci_mod_fc() to determine if the device is unavailable and
in this case simply ignore the error. Once the device is reset
zpci_hot_reset_device() will then correctly set the domain's DMA
translation tables.
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20221109142903.4080275-2-schnelle@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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The struct s390_domain_device serves the sole purpose as list entry for
the devices list of a struct s390_domain. As it contains no additional
information besides a list_head and a pointer to the struct zpci_dev we
can simplify things and just thread the device list through struct
zpci_dev directly. This removes the need to allocate during domain
attach and gets rid of one level of indirection during mapping
operations.
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20221025115657.1666860-3-schnelle@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
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This field was added in commit 44510d6fa0c0 ("s390/pci: Handling
multifunctions") but is an unused remnant of an earlier version where
the devices on the virtual bus were connected in a linked list instead
of a fixed 256 entry array of pointers.
It is also not used for the list of busses as that is threaded through
struct zpci_bus not through struct zpci_dev.
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull pci updates from Bjorn Helgaas:
"Enumeration:
- Consolidate duplicated 'next function' scanning and extend to allow
'isolated functions' on s390, similar to existing hypervisors
(Niklas Schnelle)
Resource management:
- Implement pci_iobar_pfn() for sparc, which allows us to remove the
sparc-specific pci_mmap_page_range() and pci_mmap_resource_range().
This removes the ability to map the entire PCI I/O space using
/proc/bus/pci, but we believe that's already been broken since
v2.6.28 (Arnd Bergmann)
- Move common PCI definitions to asm-generic/pci.h and rework others
to be be more specific and more encapsulated in arches that need
them (Stafford Horne)
Power management:
- Convert drivers to new *_PM_OPS macros to avoid need for '#ifdef
CONFIG_PM_SLEEP' or '__maybe_unused' (Bjorn Helgaas)
Virtualization:
- Add ACS quirk for Broadcom BCM5750x multifunction NICs that isolate
the functions but don't advertise an ACS capability (Pavan Chebbi)
Error handling:
- Clear PCI Status register during enumeration in case firmware left
errors logged (Kai-Heng Feng)
- When we have native control of AER, enable error reporting for all
devices that support AER. Previously only a few drivers enabled
this (Stefan Roese)
- Keep AER error reporting enabled for switches. Previously we
enabled this during enumeration but immediately disabled it (Stefan
Roese)
- Iterate over error counters instead of error strings to avoid
printing junk in AER sysfs counters (Mohamed Khalfella)
ASPM:
- Remove pcie_aspm_pm_state_change() so ASPM config changes, e.g.,
via sysfs, are not lost across power state changes (Kai-Heng Feng)
Endpoint framework:
- Don't stop an EPC when unbinding an EPF from it (Shunsuke Mie)
Endpoint embedded DMA controller driver:
- Simplify and clean up support for the DesignWare embedded DMA
(eDMA) controller (Frank Li, Serge Semin)
Broadcom STB PCIe controller driver:
- Avoid config space accesses when link is down because we can't
recover from the CPU aborts these cause (Jim Quinlan)
- Look for power regulators described under Root Ports in DT and
enable them before scanning the secondary bus (Jim Quinlan)
- Disable/enable regulators in suspend/resume (Jim Quinlan)
Freescale i.MX6 PCIe controller driver:
- Simplify and clean up clock and PHY management (Richard Zhu)
- Disable/enable regulators in suspend/resume (Richard Zhu)
- Set PCIE_DBI_RO_WR_EN before writing DBI registers (Richard Zhu)
- Allow speeds faster than Gen2 (Richard Zhu)
- Make link being down a non-fatal error so controller probe doesn't
fail if there are no Endpoints connected (Richard Zhu)
Loongson PCIe controller driver:
- Add ACPI and MCFG support for Loongson LS7A (Huacai Chen)
- Avoid config reads to non-existent LS2K/LS7A devices because a
hardware defect causes machine hangs (Huacai Chen)
- Work around LS7A integrated devices that report incorrect Interrupt
Pin values (Jianmin Lv)
Marvell Aardvark PCIe controller driver:
- Add support for AER and Slot capability on emulated bridge (Pali
Rohár)
MediaTek PCIe controller driver:
- Add Airoha EN7532 to DT binding (John Crispin)
- Allow building of driver for ARCH_AIROHA (Felix Fietkau)
MediaTek PCIe Gen3 controller driver:
- Print decoded LTSSM state when the link doesn't come up (Jianjun
Wang)
NVIDIA Tegra194 PCIe controller driver:
- Convert DT binding to json-schema (Vidya Sagar)
- Add DT bindings and driver support for Tegra234 Root Port and
Endpoint mode (Vidya Sagar)
- Fix some Root Port interrupt handling issues (Vidya Sagar)
- Set default Max Payload Size to 256 bytes (Vidya Sagar)
- Fix Data Link Feature capability programming (Vidya Sagar)
- Extend Endpoint mode support to devices beyond Controller-5 (Vidya
Sagar)
Qualcomm PCIe controller driver:
- Rework clock, reset, PHY power-on ordering to avoid hangs and
improve consistency (Robert Marko, Christian Marangi)
- Move pipe_clk handling to PHY drivers (Dmitry Baryshkov)
- Add IPQ60xx support (Selvam Sathappan Periakaruppan)
- Allow ASPM L1 and substates for 2.7.0 (Krishna chaitanya chundru)
- Add support for more than 32 MSI interrupts (Dmitry Baryshkov)
Renesas R-Car PCIe controller driver:
- Convert DT binding to json-schema (Herve Codina)
- Add Renesas RZ/N1D (R9A06G032) to rcar-gen2 DT binding and driver
(Herve Codina)
Samsung Exynos PCIe controller driver:
- Fix phy-exynos-pcie driver so it follows the 'phy_init() before
phy_power_on()' PHY programming model (Marek Szyprowski)
Synopsys DesignWare PCIe controller driver:
- Simplify and clean up the DWC core extensively (Serge Semin)
- Fix an issue with programming the ATU for regions that cross a 4GB
boundary (Serge Semin)
- Enable the CDM check if 'snps,enable-cdm-check' exists; previously
we skipped it if 'num-lanes' was absent (Serge Semin)
- Allocate a 32-bit DMA-able page to be MSI target instead of using a
driver data structure that may not be addressable with 32-bit
address (Will McVicker)
- Add DWC core support for more than 32 MSI interrupts (Dmitry
Baryshkov)
Xilinx Versal CPM PCIe controller driver:
- Add DT binding and driver support for Versal CPM5 Gen5 Root Port
(Bharat Kumar Gogada)"
* tag 'pci-v5.20-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (150 commits)
PCI: imx6: Support more than Gen2 speed link mode
PCI: imx6: Set PCIE_DBI_RO_WR_EN before writing DBI registers
PCI: imx6: Reformat suspend callback to keep symmetric with resume
PCI: imx6: Move the imx6_pcie_ltssm_disable() earlier
PCI: imx6: Disable clocks in reverse order of enable
PCI: imx6: Do not hide PHY driver callbacks and refine the error handling
PCI: imx6: Reduce resume time by only starting link if it was up before suspend
PCI: imx6: Mark the link down as non-fatal error
PCI: imx6: Move regulator enable out of imx6_pcie_deassert_core_reset()
PCI: imx6: Turn off regulator when system is in suspend mode
PCI: imx6: Call host init function directly in resume
PCI: imx6: Disable i.MX6QDL clock when disabling ref clocks
PCI: imx6: Propagate .host_init() errors to caller
PCI: imx6: Collect clock enables in imx6_pcie_clk_enable()
PCI: imx6: Factor out ref clock disable to match enable
PCI: imx6: Move imx6_pcie_clk_disable() earlier
PCI: imx6: Move imx6_pcie_enable_ref_clk() earlier
PCI: imx6: Move PHY management functions together
PCI: imx6: Move imx6_pcie_grp_offset(), imx6_pcie_configure_type() earlier
PCI: imx6: Convert to NOIRQ_SYSTEM_SLEEP_PM_OPS()
...
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pci_get_legacy_ide_irq() is only used on platforms that support PNP, so
many architectures define it but never use it. Replace uses of it with
ATA_PRIMARY_IRQ() and ATA_SECONDARY_IRQ(), which provide the same
functionality.
Since pci_get_legacy_ide_irq() is no longer used, remove all the
architecture-specific definitions of it as well as asm-generic/pci.h, which
only provides pci_get_legacy_ide_irq()
[bhelgaas: commit log]
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20220722214944.831438-2-shorne@gmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
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These routines will be invoked at the time an s390x vfio-pci device is
associated with a KVM (or when the association is removed), allowing
the zPCI device to enable or disable load/store intepretation mode;
this requires the host zPCI device to inform firmware of the unique
token (GISA designation) that is associated with the owning KVM.
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-17-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
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Initial setup for Adapter Event Notification Interpretation for zPCI
passthrough devices. Specifically, allocate a structure for forwarding of
adapter events and pass the address of this structure to firmware.
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-13-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
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This structure will be used to carry kvm passthrough information related to
zPCI devices.
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-12-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
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Store information about what IOAT designation types are supported by
underlying hardware as well as the largest store block size allowed.
These values will be needed by passthrough.
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-10-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
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For passthrough devices, we will need to know the GISA designation of the
guest if interpretation facilities are to be used. Setup to stash this in
the zdev and set a default of 0 (no GISA designation) for now; a subsequent
patch will set a valid GISA designation for passthrough devices.
Also, extend mpcific routines to specify this stashed designation as part
of the mpcific command.
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606203325.110625-9-mjrosato@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>
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Commit c1e18c17bda68 ("s390/pci: add zpci_set_irq()/zpci_clear_irq()")
made zpci_set_irq()/zpci_clear_irq() non-static in preparation for using
them in zpci_hot_reset_device(). The version of zpci_hot_reset_device()
that was finally merged however exploits the fact that IRQs and DMA is
implicitly disabled by clp_disable_fh() so the call to zpci_clear_irq()
was never added. There are no other calls outside pci_irq.c so lets make
both functions static.
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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When the platform detects an error on a PCI function or a service action
has been performed it is put in the error state and an error event
notification is provided to the OS.
Currently we treat all error event notifications the same and simply set
pdev->error_state = pci_channel_io_perm_failure requiring user
intervention such as use of the recover attribute to get the device
usable again. Despite requiring a manual step this also has the
disadvantage that the device is completely torn down and recreated
resulting in higher level devices such as a block or network device
being recreated. In case of a block device this also means that it may
need to be removed and added to a software raid even if that could
otherwise survive with a temporary degradation.
This is of course not ideal more so since an error notification with PEC
0x3A indicates that the platform already performed error recovery
successfully or that the error state was caused by a service action that
is now finished.
At least in this case we can assume that the error state can be reset
and the function made usable again. So as not to have the disadvantage
of a full tear down and recreation we need to coordinate this recovery
with the driver. Thankfully there is already a well defined recovery
flow for this described in Documentation/PCI/pci-error-recovery.rst.
The implementation of this is somewhat straight forward and simplified
by the fact that our recovery flow is defined per PCI function. As
a reset we use the newly introduced zpci_hot_reset_device() which also
takes the PCI function out of the error state.
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Acked-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>
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This is done by adding a zpci_hot_reset_device() call which does a low
level reset of the PCI function without changing its higher level
function state. This way it can be used while the zPCI function is bound
to a driver and with DMA tables being controlled either through the
IOMMU or DMA APIs which is prohibited when using zpci_disable_device()
as that drop existing DMA translations.
As this reset, unlike a normal FLR, also calls zpci_clear_irq() we need
to implement arch_restore_msi_irqs() and make sure we re-enable IRQs for
the PCI function if they were previously disabled.
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
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>
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The function handle of a PCI function is updated when disabling or
enabling it as well as when the function's availability changes or it
enters the error state.
Until now this only occurred either while there is no struct pci_dev
associated with the function yet or the function became unavailable.
This meant that leaving a stale function handle in the iomap either
didn't happen because there was no iomap yet or it lead to errors on PCI
access but so would the correct disabled function handle.
In the future a CLP Set PCI Function Disable/Enable cycle during PCI
device recovery may be done while the device is bound to a driver. In
this case we must update the iomap associated with the now-stale
function handle to ensure that the resulting zPCI instruction references
an accurate function handle.
Since the function handle is accessed by the PCI accessor helpers
without locking use READ_ONCE()/WRITE_ONCE() to mark this access and
prevent compiler optimizations that would move the load/store.
With that infrastructure in place let's also properly update the
function handle in the existing cases. This makes sure that in the
future debugging of a zPCI function access through the handle will
show an up to date handle reducing the chance of confusion. Also it
makes sure we have one single place where a zPCI function handle is
updated after initialization.
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
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>
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Since commit 2a671f77ee49 ("s390/pci: fix use after free of zpci_dev")
the reference count of a zpci_dev is incremented between
pcibios_add_device() and pcibios_release_device() which was supposed to
prevent the zpci_dev from being freed while the common PCI code has
access to it. It was missed however that the handling of zPCI
availability events assumed that once zpci_zdev_put() was called no
later availability event would still see the device. With the previously
mentioned commit however this assumption no longer holds and we must
make sure that we only drop the initial long-lived reference the zPCI
subsystem holds exactly once.
Do so by introducing a zpci_device_reserved() function that handles when
a device is reserved. Here we make sure the zpci_dev will not be
considered for further events by removing it from the zpci_list.
This also means that the device actually stays in the
ZPCI_FN_STATE_RESERVED state between the time we know it has been
reserved and the final reference going away. We thus need to consider it
a real state instead of just a conceptual state after the removal. The
final cleanup of PCI resources, removal from zbus, and destruction of
the IOMMU stays in zpci_release_device() to make sure holders of the
reference do see valid data until the release.
Fixes: 2a671f77ee49 ("s390/pci: fix use after free of zpci_dev")
Cc: stable@vger.kernel.org
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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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>
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Currently clp_get_state() and clp_refresh_fh() awkwardly use the
clp_list_pci() callback mechanism to find the entry for a specific FID
and update its zdev, respectively return its state.
This is both needlessly complex and means we are always going through
the entire PCI function list even if the FID has already been found.
Instead lets introduce a clp_find_pci() function to find a specific
entry and share the CLP List PCI request handling code with
clp_list_pci().
With that in place we can also easily make the function handle a simple
out parameter instead of directly altering the zdev allowing easier
access to the updated function handle by the caller.
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>
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Instead of always treating CLP_RC_SETPCIFN_ALRDY as success and blindly
updating the function handle restrict this special handling to the
disable case by moving it into zpci_disable_device() and still treating
it as an error while also updating the function handle such that
a subsequent zpci_disable_device() succeeds or the caller can ignore the
error when aborting is not an option such as for zPCI event 0x304.
Also print this occurrence to the log such that an admin can tell why
a disable operation returned an error.
A mismatch between the state of the underlying device and our view of it
can naturally happen when the device suddenly enters the error state but
we haven't gotten the error notification yet, it must not happen on
enable though.
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>
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Pull the directed vs floating IRQ check into common
zpci_set_irq()/zpci_clear_irq() functions and expose them for the rest
of the zPCI subsystem. Furthermore we add a zdev flag bit to easily
check if IRQs are registered. This is needed for use in resetting a zPCI
function.
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>
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With zpci_configure_device() now always called on a device that has
already been configured on the platform level its name has become
misleading. Rename it to zpci_scan_configured_device() to signify that
the function now only handles the correct scanning of a newly configured
PCI function taking care of the special handling necessary for function
0 and functions parked waiting for a PCI bus that can't be created
without first seeing function 0.
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>
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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>
|
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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>
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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>
|
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A zPCI event with PEC 0x0301 for an existing zPCI device goes through
the same actions as enable_slot(). Similarly a zPCI event with PEC
0x0303 does the same steps as disable_slot().
We can thus unify both actions as zpci_configure_device() respectively
zpci_deconfigure_device().
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>
|
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The current zdev->state mixes the configuration states supported by CLP
with an additional Online state which is used inconsistently to include
enabled zPCI functions which are not yet visible to the common PCI
subsytem. In preparation for a clean separation between architected
configuration states and fine grained function states remove the Online
function state.
Where we previously checked for Online it is more accurate to check if
the function is enabled to avoid an edge case where a disabled device
was still treated as Online. This also simplifies checks whether
a function is configured as this is now directly reflected by its
function state.
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>
|
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In commit 05bc1be6db4b2 ("s390/pci: create zPCI bus") we removed the
pci_dev_put() call matching the earlier pci_get_slot() done as part of
__zpci_event_availability(). This was based on the wrong understanding
that the device_put() done as part of pci_destroy_device() would counter
the pci_get_slot() when it only counters the initial reference. This
same understanding and existing bad example also lead to not doing
a pci_dev_put() in zpci_remove_device().
Since releasing the PCI devices, unlike releasing the PCI slot, does not
print any debug message for testing I added one in pci_release_dev().
This revealed that we are indeed leaking the PCI device on PCI
hotunplug. Further testing also revealed another missing pci_dev_put() in
disable_slot().
Fix this by adding the missing pci_dev_put() in disable_slot() and fix
zpci_remove_device() with the correct pci_dev_put() calls. Also instead
of calling pci_get_slot() in __zpci_event_availability() to determine if
a PCI device is registered and then doing the same again in
zpci_remove_device() do this once in zpci_remove_device() which makes
sure that the pdev in __zpci_event_availability() is only used for the
result of pci_scan_single_device() which does not need a reference count
decremnt as its ownership goes to the PCI bus.
Also move the check if zdev->zbus->bus is set into zpci_remove_device()
since it may be that we're removing a device with devfn != 0 which never
had a PCI bus. So we can still set the pdev->error_state to indicate
that the device is not usable anymore, add a flag to set the error state.
Fixes: 05bc1be6db4b2 ("s390/pci: create zPCI bus")
Cc: <stable@vger.kernel.org> # 5.8+: e1bff843cde6 s390/pci: remove superfluous zdev->zbus check
Cc: <stable@vger.kernel.org> # 5.8+: ba764dd703fe s390/pci: refactor zpci_create_device()
Cc: <stable@vger.kernel.org> # 5.8+
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>
|
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Currently zpci_create_device() is only called in clp_add_pci_device()
which allocates the memory for the struct zpci_dev being created. There
is little separation of concerns as only both functions together can
create a zpci_dev and the only CLP specific code in
clp_add_pci_device() is a call to clp_query_pci_fn().
Improve this by removing clp_add_pci_device() and refactor
zpci_create_device() such that it alone creates and initializes the
zpci_dev given the FID and Function Handle. For this we need to make
clp_query_pci_fn() non-static. While at it remove the function handle
parameter since we can just take that from the zpci_dev. Also move
adding to the zpci_list to after the zdev has been fully created which
eliminates a window where a partially initialized zdev can be found by
get_zdev_by_fid().
Acked-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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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
...
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We'll need to keep track of whether or not the byte string in util_str is
valid and thus needs to be passed to a vfio-pci passthrough device.
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Niklas Schnelle <schnelle@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
|
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In preparation for passing the info on to vfio-pci devices, stash the
supported PCI version for the target device in the zpci_dev.
Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Niklas Schnelle <schnelle@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
|
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arch/s390/pci/pci_bus.h: zpci_bus_init - only declaration left after
commit 05bc1be6db4b ("s390/pci: create zPCI bus")
arch/s390/include/asm/gmap.h: gmap_pte_notify - only declaration left
after commit 4be130a08420 ("s390/mm: add shadow gmap support")
arch/s390/include/asm/pgalloc.h: rcu_table_freelist_finish - only
declaration left after commit 36409f6353fc ("[S390] use generic RCU
page-table freeing code")
arch/s390/include/asm/tlbflush.h: smp_ptlb_all - only declaration left
after commit 5a79859ae0f3 ("s390: remove 31 bit support")
arch/s390/include/asm/vtimer.h: init_cpu_vtimer - only declaration left
after commit b5f87f15e200 ("s390/idle: consolidate idle functions and
definitions")
arch/s390/include/asm/pci.h: zpci_debug_info - only declaration left
after commit 386aa051fb4b ("s390/pci: remove per device debug attribute")
arch/s390/include/asm/vdso.h: vdso_alloc_boot_cpu - only declaration
left after commit 4bff8cb54502 ("s390: convert to GENERIC_VDSO")
arch/s390/include/asm/smp.h: smp_vcpu_scheduled - only declaration left
after commit 67626fadd269 ("s390: enforce CONFIG_SMP")
arch/s390/kernel/entry.h: restart_call_handler - only declaration left
after commit 8b646bd75908 ("[S390] rework smp code")
arch/s390/kernel/entry.h: startup_init_nobss - only declaration left
after commit 2e83e0eb85ca ("s390: clean .bss before running uncompressed
kernel")
arch/s390/kernel/entry.h: s390_early_resume - only declaration left after
commit 394216275c7d ("s390: remove broken hibernate / power management
support")
drivers/s390/char/raw3270.h: raw3270_request_alloc_bootmem - only
declaration left after commit 33403dcfcdfd ("[S390] 3270 console:
convert from bootmem to slab")
drivers/s390/cio/device.h: ccw_device_schedule_sch_unregister - only
declaration left after commit 37de53bb5290 ("[S390] cio: introduce ccw
device todos")
drivers/s390/char/tape.h: tape_hotplug_event - has only declaration
since recorded git history.
drivers/s390/char/tape.h: tape_oper_handler - has only declaration since
recorded git history.
drivers/s390/char/tape.h: tape_noper_handler - has only declaration
since recorded git history.
drivers/s390/char/tape_std.h: tape_std_check_locate - only declaration
left after commit 161beff8f40d ("s390/tape: remove tape block leftovers")
drivers/s390/char/tape_std.h: tape_std_default_handler - has only
declaration since recorded git history.
drivers/s390/char/tape_std.h: tape_std_unexpect_uchk_handler - has only
declaration since recorded git history.
drivers/s390/char/tape_std.h: tape_std_irq - has only declaration since
recorded git history.
drivers/s390/char/tape_std.h: tape_std_error_recovery - has only
declaration since recorded git history.
drivers/s390/char/tape_std.h: tape_std_error_recovery_has_failed -
has only declaration since recorded git history.
drivers/s390/char/tape_std.h: tape_std_error_recovery_succeded - has
only declaration since recorded git history.
drivers/s390/char/tape_std.h: tape_std_error_recovery_do_retry - has
only declaration since recorded git history.
drivers/s390/char/tape_std.h: tape_std_error_recovery_read_opposite -
has only declaration since recorded git history.
drivers/s390/char/tape_std.h: tape_std_error_recovery_HWBUG - has only
declaration since recorded git history.
Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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clp_rescan_pci_devices_simple() is neither simpler than
clp_scan_pci_devices() nor does it really scan PCI devices, in particular
it will neither add newly discovered devices nor remove those which
disappeared.
Instead it only refreshes PCI function handles and also
has just a single callsite in the same translation unit left which
in fact only refreshes one specific function handle identified by
a FID.
Clarify this by renaming the function and its helper to
clp_refresh_fh() respectvely __clp_refresh_fh() and make it take
a fid directly which saves us dealing with the NULL case which
updated all function handles but is not used anymore.
Furthermore since the only callsite is in the same translation unit
make it static.
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>
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there is only one call site of clp_rescan_pci_devices() and
all the function does is call zpci_remove_reserved_devices()
followed by a duplicating clp_scan_pci_devices().
So inline the single call as a call to zpci_remove_reserved_devices()
and clp_scan_pci_devices() and remove the function.
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>
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the only caller of this was removed as part of the suspend/resume
removal so no need to keep this function around.
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>
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With our current support for the new MIO PCI instructions, write
combining/write back MMIO memory can be obtained via the pci_iomap_wc()
and pci_iomap_wc_range() functions.
This is achieved by using the write back address for a specific bar
as provided in clp_store_query_pci_fn()
These functions are however not widely used and instead drivers often
rely on ioremap_wc() and ioremap_prot(), which on other platforms enable
write combining using a PTE flag set through the pgrprot value.
While we do not have a write combining flag in the low order flag bits
of the PTE like x86_64 does, with MIO support, there is a write back bit
in the physical address (bit 1 on z15) and thus also the PTE.
Which bit is used to toggle write back and whether it is available at
all, is however not fixed in the architecture. Instead we get this
information from the CLP Store Logical Processor Characteristics for PCI
command. When the write back bit is not provided we fall back to the
existing behavior.
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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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>
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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>
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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>
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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>
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Firmware provides the bus/devfn part of the PCI addresses of a zPCI
function inside the new field RID of the CLP query PCI function
with a bit to know if this field is available to use.
Let's add these fields to the clp_rsp_query_pci structure,
add corresponding fields to zdev and initialize them.
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>
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Using PCI multifunctions in S390 is a new feature we may want
to ignore to continue provide the same topology as in the past
to userland even if the configuration supports exposing the
topology of a multi-Function device.
A new boolean parameters allows to overwrite the kernel
pci configuration:
- pci=norid when on, disallow the use a new firmware field,
RID, which provides the PCI <bus>:<device>.<function> part
of the PCI address.
To be used in the following patches and satisfy the checkpatch.pl
the variable is exposed in pci.h
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>
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In the future the bus sysdata may not directly point to the
zpci_dev.
In preparation of upcoming patches let us abstract the
access to the zpci_dev from the device inside the pci device.
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>
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Add SysFS attribute that provides the port number for PCI functions
representing a single port of a multi-port device.
Signed-off-by: Alexander Schmidt <alexs@linux.ibm.com>
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>
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When UID checking is enabled a UID value of 0 is invalid and can not be
set by the user. On z/VM it is however used to indicate an unset UID.
Until now, this lead to the behavior that one PCI function could be
attached with UID 0 after which z/VM would prohibit further attachment.
Now if the user then turns off UID checking in z/VM the user could
seemingly attach additional PCI functions that would however not show up
in Linux as that would not be informed of the change in UID checking
mode. This is unexpected and confusing and lead to bug reports against
Linux.
Instead now, if we encounter an unset UID value of 0 treat it as
indicating that UID checking was turned off, switch to automatic domain
allocation, and warn the user of the possible misconfiguration.
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
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