Reported by 0-day test infrastructure.

Fixes: ecaa1f6a ("vfio-pci: Add VGA arbiter client")
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

We can save some power by putting devices that are bound to vfio-pci
but not in use by the user in the D3hot power state.  Devices get
woken into D0 when opened by the user.  Resets return the device to
D0, so we need to re-apply the low power state after a bus reset.
It's tempting to try to use D3cold, but we have no reason to inhibit
hotplug of idle devices and we might get into a loop of having the
device disappear before we have a chance to try to use it.

A new module parameter allows this feature to be disabled if there are
devices that misbehave as a result of this change.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

As indicated in the comment, this is not entirely uncommon and
causes user concern for no reason.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

This copies the same support from pci-stub for exactly the same
purpose, enabling a set of PCI IDs to be automatically added to the
driver's dynamic ID table at module load time.  The code here is
pretty simple and both vfio-pci and pci-stub are fairly unique in
being meta drivers, capable of attaching to any device, so there's no
attempt made to generalize the code into pci-core.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

If VFIO VGA access is disabled for the user, either by CONFIG option
or module parameter, we can often opt-out of VGA arbitration.  We can
do this when PCI bridge control of VGA routing is possible.  This
means that we must have a parent bridge and there must only be a
single VGA device below that bridge.  Fortunately this is the typical
case for discrete GPUs.

Doing this allows us to minimize the impact of additional GPUs, in
terms of VGA arbitration, when they are only used via vfio-pci for
non-VGA applications.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Add a module option so that we don't require a CONFIG change and
kernel rebuild to disable VGA support.  Not only can VGA support be
troublesome in itself, but by disabling it we can reduce the impact
to host devices by doing a VGA arbitration opt-out.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

vga_set_legacy_decoding() is defined in drivers/gpu/vga/vgaarb.c,
which is only compiled with CONFIG_VGA_ARB.  A caller would
therefore get an undefined symbol if the VGA arbiter is not
enabled.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>

An unintended consequence of commit 42ac9bd1 ("vfio: initialize
the virqfd workqueue in VFIO generic code") is that the vfio module
is renamed to vfio_core so that it can include both vfio and virqfd.
That's a user visible change that may break module loading scritps
and it imposes eventfd support as a dependency on the core vfio code,
which it's really not.  virqfd is intended to be provided as a service
to vfio bus drivers, so instead of wrapping it into vfio.ko, we can
make it a stand-alone module toggled by vfio bus drivers.  This has
the additional benefit of removing initialization and exit from the
core vfio code.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

The next code fragment "list_for_each_entry" is not depend on "minor". With this
patch, the free of "minor" in "list_for_each_entry" can be reduced, and there is
no functional change.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

With this patch the VFIO user will be able to set an eventfd that can be
used in order to mask and unmask IRQs of platform devices.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Now we have finally completely decoupled virqfd from VFIO_PCI. We can
initialize it from the VFIO generic code, in order to safely use it from
multiple independent VFIO bus drivers.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

The virqfd functionality that is used by VFIO_PCI to implement interrupt
masking and unmasking via an eventfd, is generic enough and can be reused
by another driver. Move it to a separate file in order to allow the code
to be shared.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

VFIO_PCI passes the VFIO device structure *vdev via eventfd to the handler
that implements masking/unmasking of IRQs via an eventfd. We can replace
it in the virqfd infrastructure with an opaque type so we can make use
of the mechanism from other VFIO bus drivers.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

The Virqfd code needs to keep accesses to any struct *virqfd safe, but
this comes into play only when creating or destroying eventfds, so sharing
the same spinlock with the VFIO bus driver is not necessary.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

The functions vfio_pci_virqfd_init and vfio_pci_virqfd_exit are not really
PCI specific, since we plan to reuse the virqfd code with more VFIO drivers
in addition to VFIO_PCI.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
[Baptiste Reynal: Move rename vfio_pci_virqfd_init and vfio_pci_virqfd_exit
from "vfio: add a vfio_ prefix to virqfd_enable and virqfd_disable and export"]
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

We want to reuse virqfd functionality in multiple VFIO drivers; before
moving these functions to core VFIO, add the vfio_ prefix to the
virqfd_enable and virqfd_disable functions, and export them so they can
be used from other modules.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Level sensitive interrupts are exposed as maskable and automasked
interrupts and are masked and disabled automatically when they fire.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
[Baptiste Reynal: Move masked interrupt initialization from "vfio/platform:
trigger an interrupt via eventfd"]
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

This patch allows to set an eventfd for a platform device's interrupt,
and also to trigger the interrupt eventfd from userspace for testing.
Level sensitive interrupts are marked as maskable and are handled in
a later patch. Edge triggered interrupts are not advertised as maskable
and are implemented here using a simple and efficient IRQ handler.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
[Baptiste Reynal: fix masked interrupt initialization]
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

This patch is a skeleton for the VFIO_DEVICE_SET_IRQS IOCTL, around which
most IRQ functionality is implemented in VFIO.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Return information for the interrupts exposed by the device.
This patch extends VFIO_DEVICE_GET_INFO with the number of IRQs
and enables VFIO_DEVICE_GET_IRQ_INFO.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Allow to memory map the MMIO regions of the device so userspace can
directly access them. PIO regions are not being handled at this point.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

VFIO returns a file descriptor which we can use to manipulate the memory
regions of the device. Usually, the user will mmap memory regions that are
addressable on page boundaries, however for memory regions where this is
not the case we cannot provide mmap functionality due to security concerns.
For this reason we also allow to use read and write functions to the file
descriptor pointing to the memory regions.

We implement this functionality only for MMIO regions of platform devices;
PIO regions are not being handled at this point.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

This patch enables the IOCTLs VFIO_DEVICE_GET_REGION_INFO ioctl call,
which allows the user to learn about the available MMIO resources of
a device.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

A VFIO userspace driver will start by opening the VFIO device
that corresponds to an IOMMU group, and will use the ioctl interface
to get the basic device info, such as number of memory regions and
interrupts, and their properties. This patch enables the
VFIO_DEVICE_GET_INFO ioctl call.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
[Baptiste Reynal: added include in vfio_platform_common.c]
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Enable building the VFIO AMBA driver. VFIO_AMBA depends on VFIO_PLATFORM,
since it is sharing a portion of the code, and it is essentially implemented
as a platform device whose resources are discovered via AMBA specific APIs
in the kernel.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Add support for discovering AMBA devices with VFIO and handle them
similarly to Linux platform devices.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Enable building the VFIO PLATFORM driver that allows to use Linux platform
devices with VFIO.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Driver to bind to Linux platform devices, and callbacks to discover their
resources to be used by the main VFIO PLATFORM code.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

This patch forms the common skeleton code for platform devices support
with VFIO. This will include the core functionality of VFIO_PLATFORM,
however binding to the device and discovering the device resources will
be done with the help of a separate file where any Linux platform bus
specific code will reside.

This will allow us to implement support for also discovering AMBA devices
and their resources, but still reuse a large part of the VFIO_PLATFORM
implementation.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
[Baptiste Reynal: added includes in vfio_platform_private.h]
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

Pull drm fix from Dave Airlie:
 "An oops snuck in in an -rc3 patch, this fixes it"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  [PATCH] drm/mm: Fix support 4 GiB and larger ranges

Pull clock framework fixes from Michael Turquette:
 "The clk fixes for 4.0-rc4 comprise three themes.

  First are the usual driver fixes for new regressions since v3.19.

  Second are fixes to the common clock divider type caused by recent
  changes to how we round clock rates.  This affects many clock drivers
  that use this common code.

  Finally there are fixes for drivers that improperly compared struct
  clk pointers (drivers must not deref these pointers).  While some of
  these drivers have done this for a long time, this did not cause a
  problem until we started generating unique struct clk pointers for
  every consumer.  A new function, clk_is_match was introduced to get
  these drivers working again and they are fixed up to no longer deref
  the pointers themselves"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  ASoC: kirkwood: fix struct clk pointer comparing
  ASoC: fsl_spdif: fix struct clk pointer comparing
  ARM: imx: fix struct clk pointer comparing
  clk: introduce clk_is_match
  clk: don't export static symbol
  clk: divider: fix calculation of initial best divider when rounding to closest
  clk: divider: fix selection of divider when rounding to closest
  clk: divider: fix calculation of maximal parent rate for a given divider
  clk: divider: return real rate instead of divider value
  clk: qcom: fix platform_no_drv_owner.cocci warnings
  clk: qcom: fix platform_no_drv_owner.cocci warnings
  clk: qcom: Add PLL4 vote clock
  clk: qcom: lcc-msm8960: Fix PLL rate detection
  clk: qcom: Fix slimbus n and m val offsets
  clk: ti: Fix FAPLL parent enable bit handling

bad argument if(tmp)... in check_free_hole

fix oops: kernel BUG at drivers/gpu/drm/drm_mm.c:305!

[airlied: excellent, this was my task for today].
Signed-off-by: Krzysztof Kolasa <kkolasa@winsoft.pl>
Reviewed-by: Chris wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>

Pull ARM SoC fixes from Arnd Bergmann:
 "This is a rather unpleasantly large set of bug fixes for arm-soc, Most
  of them because of cross-tree dependencies for Exynos where we should
  have figured out the right path to merge things before the merge
  window, and then the maintainer being unable to sort things out in
  time during a business trip.

  The other changes contained here are the usual collection:

  MAINTAINERS file updates
   - Gregory Clement is now a co-maintainer for the legacy Marvell EBU
     platforms
   - A MAINTAINERS entry for the Freescale Vybrid platform that was
     added last year
   - Matt Porter no longer works as a maintainer on Broadcom SoCs

  Build-time issues
   - A compile-time error for at91
   - Several minor DT fixes on at91, imx, exynos, socfpga, and omap
   - The new digicolor platform was not correctly enabled at all

  Configuration issues
   - Two defconfig fix for regressions using USB on versatile express
     and on OMAP3
   - Enabling all 8 CPUs on Allwinner/SUNxi
   - Enabling the new STiH410 platform to be usable

  Bug fixes in platform code
   - A missing barrier for socfpga
   - Fixing LPDDR1 self-refresh mode on at91
   - Fixing RTC interrupt numbers on Exynos3250
   - Fixing a cache-coherency issues in CPU power-down on Exynos5
   - Multiple small OMAP power management fixes"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (69 commits)
  MAINTAINERS: Add myself as co-maintainer to the legacy support of the mvebu SoCs
  ARM: at91: pm_slowclock: fix the compilation error
  ARM: at91/dt: fix USB high-speed clock to select UTMI
  ARM: at91/dt: fix at91 udc compatible strings
  ARM: at91/dt: declare matrix node as a syscon device
  ARM: vexpress: update CONFIG_USB_ISP1760 option
  ARM: digicolor: add the machine directory to Makefile
  ARM: STi: Add STiH410 SoC support
  MAINTAINERS: add Freescale Vybrid SoC
  MAINTAINERS: Remove self as ARM mach-bcm co-maintainer
  ARM: imx6sl-evk: set swbst_reg as vbus's parent reg
  ARM: imx6qdl-sabresd: set swbst_reg as vbus's parent reg
  ARM: at91/dt: at91sam9261: fix clocks and clock-names in udc definition
  ARM: OMAP2+: Fix wl12xx on dm3730-evm with mainline u-boot
  ARM: OMAP: enable TWL4030_USB in omap2plus_defconfig
  ARM: dts: dra7x-evm: avoid possible contention while muxing on CAN lines
  ARM: dts: dra7x-evm: Don't use dcan1_rx.gpio1_15 in DCAN pinctrl
  ARM: dts: am43xx: fix SLEWCTRL_FAST pinctrl binding
  ARM: dts: am33xx: fix SLEWCTRL_FAST pinctrl binding
  ARM: dts: OMAP5: fix polling intervals for thermal zones
  ...

Pull irqchip fixes from Jason Cooper:
 "armada-370-xp:
   - Chained per-cpu interrupts

  gic{,-v3,v3-its}"
   - Various fixes for safer operation"

* tag 'irqchip-fixes-4.0' of git://git.infradead.org/users/jcooper/linux:
  irqchip: gicv3-its: Support safe initialization
  irqchip: gicv3-its: Define macros for GITS_CTLR fields
  irqchip: gicv3-its: Add limitation to page order
  irqchip: gicv3-its: Use 64KB page as default granule
  irqchip: gicv3-its: Zero itt before handling to hardware
  irqchip: gic-v3: Fix out of bounds access to cpu_logical_map
  irqchip: gic: Fix unsafe locking reported by lockdep
  irqchip: gicv3-its: Fix unsafe locking reported by lockdep
  irqchip: gicv3-its: Iterate over PCI aliases to generate ITS configuration
  irqchip: gicv3-its: Allocate enough memory for the full range of DeviceID
  irqchip: gicv3-its: Fix ITS CPU init
  irqchip: armada-370-xp: Fix chained per-cpu interrupts

Pull drm fixes from Dave Airlie:
 "Misc i915, vmwgfx and radeon fixes along with a fix for one of those
  recursive sleep mutex debug cases in the mst code"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/vmwgfx: Fix an issue with the device losing its irq line on module unload
  drm/vmwgfx: Correctly NULLify dma buffer pointer on failure
  drm/vmwgfx: Reorder device takedown somewhat
  drm/vmwgfx: Fix a couple of lock dependency violations
  drm/radeon: drop setting UPLL to sleep mode
  drm/radeon: fix wait to actually occur after the signaling callback
  drm/i915: Prevent TLB error on first execution on SNB
  drm/i915: Do both mt and gen6 style forcewake reset on ivb probe
  drm/i915: Make WAIT_IOCTL negative timeouts be indefinite again
  drm/i915: use in_interrupt() not in_irq() to check context
  drm/mst: fix recursive sleep warning on qlock
  drm: Don't assign fbs for universal cursor support to files

Pull SCSI fix from James Bottomley:
 "This is a simple fix for a domain revalidation crash which has
  recently turned up in the libsas code (applies to mvsas, isc and
  aic94xx)"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  libsas: Fix Kernel Crash in smp_execute_task

Pull file locking bugfix from Jeff Layton:
 "Just a small fix for a potential problem in one of the lease
  tracepoints"

* tag 'locks-v4.0-4' of git://git.samba.org/jlayton/linux:
  locks: fix generic_delete_lease tracepoint to use victim pointer