The flags entry is there to tell the user that some
optional information is available.
Since we report the iova_pgsizes signal it to the user
by setting the flags to VFIO_IOMMU_INFO_PGSIZES.
Signed-off-by: Pierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There is really no way to safely give a user full access to a DMA
capable device without an IOMMU to protect the host system. There is
also no way to provide DMA translation, for use cases such as device
assignment to virtual machines. However, there are still those users
that want userspace drivers even under those conditions. The UIO
driver exists for this use case, but does not provide the degree of
device access and programming that VFIO has. In an effort to avoid
code duplication, this introduces a No-IOMMU mode for VFIO.
This mode requires building VFIO with CONFIG_VFIO_NOIOMMU and enabling
the "enable_unsafe_noiommu_mode" option on the vfio driver. This
should make it very clear that this mode is not safe. Additionally,
CAP_SYS_RAWIO privileges are necessary to work with groups and
containers using this mode. Groups making use of this support are
named /dev/vfio/noiommu-$GROUP and can only make use of the special
VFIO_NOIOMMU_IOMMU for the container. Use of this mode, specifically
binding a device without a native IOMMU group to a VFIO bus driver
will taint the kernel and should therefore not be considered
supported. This patch includes no-iommu support for the vfio-pci bus
driver only.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
This loop ends with count set to -1 and not zero so the warning message
isn't printed when it should be. I've fixed this by change the postop
to a preop.
Fixes: 0990822c98 ('VFIO: platform: reset: AMD xgbe reset module')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Revert commit 033291eccb ("vfio: Include No-IOMMU mode") due to lack
of a user. This was originally intended to fill a need for the DPDK
driver, but uptake has been slow so rather than support an unproven
kernel interface revert it and revisit when userspace catches up.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The first argument to the WARN() macro has to be a condition. I'm sort
of disappointed that this code doesn't generate a compiler warning. I
guess -Wformat-extra-args doesn't work in the kernel.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
request_module already takes format strings, so no need to duplicate
the effort.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This pci_error_handlers structure is never modified, like all the other
pci_error_handlers structures, so declare it as const.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
platform_driver does not need to set an owner because
platform_driver_register() will set it.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
- Use kernel interfaces for VPD emulation (Alex Williamson)
- Platform fix for releasing IRQs (Eric Auger)
- Type1 IOMMU always advertises PAGE_SIZE support when smaller
mapping sizes are available (Eric Auger)
- Platform fixes for incorrectly using copies of structures rather
than pointers to structures (James Morse)
- Rework platform reset modules, fix leak, and add AMD xgbe reset
module (Eric Auger)
- Fix vfio_device_get_from_name() return value (Joerg Roedel)
- No-IOMMU interface (Alex Williamson)
- Fix potential out of bounds array access in PCI config handling
(Dan Carpenter)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=bI62
-----END PGP SIGNATURE-----
Merge tag 'vfio-v4.4-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
- Use kernel interfaces for VPD emulation (Alex Williamson)
- Platform fix for releasing IRQs (Eric Auger)
- Type1 IOMMU always advertises PAGE_SIZE support when smaller mapping
sizes are available (Eric Auger)
- Platform fixes for incorrectly using copies of structures rather than
pointers to structures (James Morse)
- Rework platform reset modules, fix leak, and add AMD xgbe reset
module (Eric Auger)
- Fix vfio_device_get_from_name() return value (Joerg Roedel)
- No-IOMMU interface (Alex Williamson)
- Fix potential out of bounds array access in PCI config handling (Dan
Carpenter)
* tag 'vfio-v4.4-rc1' of git://github.com/awilliam/linux-vfio:
vfio/pci: make an array larger
vfio: Include No-IOMMU mode
vfio: Fix bug in vfio_device_get_from_name()
VFIO: platform: reset: AMD xgbe reset module
vfio: platform: reset: calxedaxgmac: fix ioaddr leak
vfio: platform: add dev_info on device reset
vfio: platform: use list of registered reset function
vfio: platform: add compat in vfio_platform_device
vfio: platform: reset: calxedaxgmac: add reset function registration
vfio: platform: introduce module_vfio_reset_handler macro
vfio: platform: add capability to register a reset function
vfio: platform: introduce vfio-platform-base module
vfio/platform: store mapped memory in region, instead of an on-stack copy
vfio/type1: handle case where IOMMU does not support PAGE_SIZE size
VFIO: platform: clear IRQ_NOAUTOEN when de-assigning the IRQ
vfio/pci: Use kernel VPD access functions
vfio: Whitelist PCI bridges
Smatch complains about a possible out of bounds error:
drivers/vfio/pci/vfio_pci_config.c:1241 vfio_cap_init()
error: buffer overflow 'pci_cap_length' 20 <= 20
The problem is that pci_cap_length[] was defined as large enough to
hold "PCI_CAP_ID_AF + 1" elements. The code in vfio_cap_init() assumes
it has PCI_CAP_ID_MAX + 1 elements. Originally, PCI_CAP_ID_AF and
PCI_CAP_ID_MAX were the same but then we introduced PCI_CAP_ID_EA in
commit f80b0ba959 ("PCI: Add Enhanced Allocation register entries")
so now the array is too small.
Let's fix this by making the array size PCI_CAP_ID_MAX + 1. And let's
make a similar change to pci_ext_cap_length[] for consistency. Also
both these arrays can be made const.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There is really no way to safely give a user full access to a DMA
capable device without an IOMMU to protect the host system. There is
also no way to provide DMA translation, for use cases such as device
assignment to virtual machines. However, there are still those users
that want userspace drivers even under those conditions. The UIO
driver exists for this use case, but does not provide the degree of
device access and programming that VFIO has. In an effort to avoid
code duplication, this introduces a No-IOMMU mode for VFIO.
This mode requires building VFIO with CONFIG_VFIO_NOIOMMU and enabling
the "enable_unsafe_noiommu_mode" option on the vfio driver. This
should make it very clear that this mode is not safe. Additionally,
CAP_SYS_RAWIO privileges are necessary to work with groups and
containers using this mode. Groups making use of this support are
named /dev/vfio/noiommu-$GROUP and can only make use of the special
VFIO_NOIOMMU_IOMMU for the container. Use of this mode, specifically
binding a device without a native IOMMU group to a VFIO bus driver
will taint the kernel and should therefore not be considered
supported. This patch includes no-iommu support for the vfio-pci bus
driver only.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
The vfio_device_get_from_name() function might return a
non-NULL pointer, when called with a device name that is not
found in the list. This causes undefined behavior, in my
case calling an invalid function pointer later on:
kernel tried to execute NX-protected page - exploit attempt? (uid: 0)
BUG: unable to handle kernel paging request at ffff8800cb3ddc08
[...]
Call Trace:
[<ffffffffa03bd733>] ? vfio_group_fops_unl_ioctl+0x253/0x410 [vfio]
[<ffffffff811efc4d>] do_vfs_ioctl+0x2cd/0x4c0
[<ffffffff811f9657>] ? __fget+0x77/0xb0
[<ffffffff811efeb9>] SyS_ioctl+0x79/0x90
[<ffffffff81001bb0>] ? syscall_return_slowpath+0x50/0x130
[<ffffffff8167f776>] entry_SYSCALL_64_fastpath+0x16/0x75
Fix the issue by returning NULL when there is no device with
the requested name in the list.
Cc: stable@vger.kernel.org # v4.2+
Fixes: 4bc94d5dc9 ("vfio: Fix lockdep issue")
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch introduces a module that registers and implements a low-level
reset function for the AMD XGBE device.
it performs the following actions:
- reset the PHY
- disable auto-negotiation
- disable & clear auto-negotiation IRQ
- soft-reset the MAC
Those tiny pieces of code are inherited from the native xgbe driver.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In the current code the vfio_platform_region is copied on the stack.
As a consequence the ioaddr address is not iounmapped in the vfio
platform driver (vfio_platform_regions_cleanup). The patch uses the
pointer to the region instead.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
It might be helpful for the end-user to check the device reset
function was found by the vfio platform reset framework.
Lets store a pointer to the struct device in vfio_platform_device
and trace when the reset function is called or not found.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Remove the static lookup table and use the dynamic list of registered
reset functions instead. Also load the reset module through its alias.
The reset struct module pointer is stored in vfio_platform_device.
We also remove the useless struct device pointer parameter in
vfio_platform_get_reset.
This patch fixes the issue related to the usage of __symbol_get, which
besides from being moot, prevented compilation with CONFIG_MODULES
disabled.
Also usage of MODULE_ALIAS makes possible to add a new reset module
without needing to update the framework. This was suggested by Arnd.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Let's retrieve the compatibility string on probe and store it
in the vfio_platform_device struct
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch adds the reset function registration/unregistration.
This is handled through the module_vfio_reset_handler macro. This
latter also defines a MODULE_ALIAS which simplifies the load from
vfio-platform.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The module_vfio_reset_handler macro
- define a module alias
- implement module init/exit function which respectively registers
and unregisters the reset function.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In preparation for subsequent changes in reset function lookup,
lets introduce a dynamic list of reset combos (compat string,
reset module, reset function). The list can be populated/voided with
vfio_platform_register/unregister_reset. Those are not yet used in
this patch.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
To prepare for vfio platform reset rework let's build
vfio_platform_common.c and vfio_platform_irq.c in a separate
module from vfio-platform and vfio-amba. This makes possible
to have separate module inits and works around a race between
platform driver init and vfio reset module init: that way we
make sure symbols exported by base are available when vfio-platform
driver gets probed.
The open/release being implemented in the base module, the ref
count is applied to the parent module instead.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio_platform_{read,write}_mmio() call ioremap_nocache() to map
a region of io memory, which they store in struct vfio_platform_region to
be eventually re-used, or unmapped by vfio_platform_regions_cleanup().
These functions receive a copy of their struct vfio_platform_region
argument on the stack - so these mapped areas are always allocated, and
always leaked.
Pass this argument as a pointer instead.
Fixes: 6e3f264560 "vfio/platform: read and write support for the device fd"
Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Tested-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Current vfio_pgsize_bitmap code hides the supported IOMMU page
sizes smaller than PAGE_SIZE. As a result, in case the IOMMU
does not support PAGE_SIZE page, the alignment check on map/unmap
is done with larger page sizes, if any. This can fail although
mapping could be done with pages smaller than PAGE_SIZE.
This patch modifies vfio_pgsize_bitmap implementation so that,
in case the IOMMU supports page sizes smaller than PAGE_SIZE
we pretend PAGE_SIZE is supported and hide sub-PAGE_SIZE sizes.
That way the user will be able to map/unmap buffers whose size/
start address is aligned with PAGE_SIZE. Pinning code uses that
granularity while iommu driver can use the sub-PAGE_SIZE size
to map the buffer.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The vfio platform driver currently sets the IRQ_NOAUTOEN before
doing the request_irq to properly handle the user masking. However
it does not clear it when de-assigning the IRQ. This brings issues
when loading the native driver again which may not explicitly enable
the IRQ. This problem was observed with xgbe driver.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The PCI VPD capability operates on a set of window registers in PCI
config space. Writing to the address register triggers either a read
or write, depending on the setting of the PCI_VPD_ADDR_F bit within
the address register. The data register provides either the source
for writes or the target for reads.
This model is susceptible to being broken by concurrent access, for
which the kernel has adopted a set of access functions to serialize
these registers. Additionally, commits like 932c435cab ("PCI: Add
dev_flags bit to access VPD through function 0") and 7aa6ca4d39
("PCI: Add VPD function 0 quirk for Intel Ethernet devices") indicate
that VPD registers can be shared between functions on multifunction
devices creating dependencies between otherwise independent devices.
Fortunately it's quite easy to emulate the VPD registers, simply
storing copies of the address and data registers in memory and
triggering a VPD read or write on writes to the address register.
This allows vfio users to avoid seeing spurious register changes from
accesses on other devices and enables the use of shared quirks in the
host kernel. We can theoretically still race with access through
sysfs, but the window of opportunity is much smaller.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Mark Rustad <mark.d.rustad@intel.com>
When determining whether a group is viable, we already allow devices
bound to pcieport. Generalize this to include any PCI bridge device.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch adds the registration/unregistration of an
irq_bypass_producer for MSI/MSIx on vfio pci devices.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Feng Wu <feng.wu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When we open a device file descriptor, we currently have the
following:
vfio_group_get_device_fd()
mutex_lock(&group->device_lock);
open()
...
if (ret)
release()
If we hit that error case, we call the backend driver release path,
which for vfio-pci looks like this:
vfio_pci_release()
vfio_pci_disable()
vfio_pci_try_bus_reset()
vfio_pci_get_devs()
vfio_device_get_from_dev()
vfio_group_get_device()
mutex_lock(&group->device_lock);
Whoops, we've stumbled back onto group.device_lock and created a
deadlock. There's a low likelihood of ever seeing this play out, but
obviously it needs to be fixed. To do that we can use a reference to
the vfio_device for vfio_group_get_device_fd() rather than holding the
lock. There was a loop in this function, theoretically allowing
multiple devices with the same name, but in practice we don't expect
such a thing to happen and the code is already aborting from the loop
with break on any sort of error rather than continuing and only
parsing the first match anyway, so the loop was effectively unused
already.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Fixes: 20f300175a ("vfio/pci: Fix racy vfio_device_get_from_dev() call")
Reported-by: Joerg Roedel <joro@8bytes.org>
Tested-by: Joerg Roedel <jroedel@suse.de>
- Disable the 32-bit vdso when building LE, so we can build with a 64-bit only
toolchain.
- EEH fixes from Gavin & Richard.
- Enable the sys_kcmp syscall from Laurent.
- Sysfs control for fastsleep workaround from Shreyas.
- Expose OPAL events as an irq chip by Alistair.
- MSI ops moved to pci_controller_ops by Daniel.
- Fix for kernel to userspace backtraces for perf from Anton.
- Merge pseries and pseries_le defconfigs from Cyril.
- CXL in-kernel API from Mikey.
- OPAL prd driver from Jeremy.
- Fix for DSCR handling & tests from Anshuman.
- Powernv flash mtd driver from Cyril.
- Dynamic DMA Window support on powernv from Alexey.
- LLVM clang fixes & workarounds from Anton.
- Reworked version of the patch to abort syscalls when transactional.
- Fix the swap encoding to support 4TB, from Aneesh.
- Various fixes as usual.
- Freescale updates from Scott: Highlights include more 8xx optimizations, an
e6500 hugetlb optimization, QMan device tree nodes, t1024/t1023 support, and
various fixes and cleanup.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=d9Wh
-----END PGP SIGNATURE-----
Merge tag 'powerpc-4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux
Pull powerpc updates from Michael Ellerman:
- disable the 32-bit vdso when building LE, so we can build with a
64-bit only toolchain.
- EEH fixes from Gavin & Richard.
- enable the sys_kcmp syscall from Laurent.
- sysfs control for fastsleep workaround from Shreyas.
- expose OPAL events as an irq chip by Alistair.
- MSI ops moved to pci_controller_ops by Daniel.
- fix for kernel to userspace backtraces for perf from Anton.
- merge pseries and pseries_le defconfigs from Cyril.
- CXL in-kernel API from Mikey.
- OPAL prd driver from Jeremy.
- fix for DSCR handling & tests from Anshuman.
- Powernv flash mtd driver from Cyril.
- dynamic DMA Window support on powernv from Alexey.
- LLVM clang fixes & workarounds from Anton.
- reworked version of the patch to abort syscalls when transactional.
- fix the swap encoding to support 4TB, from Aneesh.
- various fixes as usual.
- Freescale updates from Scott: Highlights include more 8xx
optimizations, an e6500 hugetlb optimization, QMan device tree nodes,
t1024/t1023 support, and various fixes and cleanup.
* tag 'powerpc-4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (180 commits)
cxl: Fix typo in debug print
cxl: Add CXL_KERNEL_API config option
powerpc/powernv: Fix wrong IOMMU table in pnv_ioda_setup_bus_dma()
powerpc/mm: Change the swap encoding in pte.
powerpc/mm: PTE_RPN_MAX is not used, remove the same
powerpc/tm: Abort syscalls in active transactions
powerpc/iommu/ioda2: Enable compile with IOV=on and IOMMU_API=off
powerpc/include: Add opal-prd to installed uapi headers
powerpc/powernv: fix construction of opal PRD messages
powerpc/powernv: Increase opal-irqchip initcall priority
powerpc: Make doorbell check preemption safe
powerpc/powernv: pnv_init_idle_states() should only run on powernv
macintosh/nvram: Remove as unused
powerpc: Don't use gcc specific options on clang
powerpc: Don't use -mno-strict-align on clang
powerpc: Only use -mtraceback=no, -mno-string and -msoft-float if toolchain supports it
powerpc: Only use -mabi=altivec if toolchain supports it
powerpc: Fix duplicate const clang warning in user access code
vfio: powerpc/spapr: Support Dynamic DMA windows
vfio: powerpc/spapr: Register memory and define IOMMU v2
...
This patch enables building VFIO platform and derivatives on ARM64.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Tested-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch introduces a module that registers and implements a basic
reset function for the Calxeda xgmac device. This latter basically disables
interrupts and stops DMA transfers.
The reset function code is inherited from the native calxeda xgmac driver.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Tested-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The reset function lookup happens on vfio-platform probe. The reset
module load is requested and a reference to the function symbol is
hold. The reference is released on vfio-platform remove.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Tested-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
A new reset callback is introduced. If this callback is populated,
the reset is invoked on device first open/last close or upon userspace
ioctl. The modality is exposed on VFIO_DEVICE_GET_INFO.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Tested-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This patch introduces the vfio_platform_reset_combo struct that
stores all the information useful to handle the reset modality:
compat string, name of the reset function, name of the module that
implements the reset function. A lookup table of such structures
is added, currently void.
Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Tested-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This adds create/remove window ioctls to create and remove DMA windows.
sPAPR defines a Dynamic DMA windows capability which allows
para-virtualized guests to create additional DMA windows on a PCI bus.
The existing linux kernels use this new window to map the entire guest
memory and switch to the direct DMA operations saving time on map/unmap
requests which would normally happen in a big amounts.
This adds 2 ioctl handlers - VFIO_IOMMU_SPAPR_TCE_CREATE and
VFIO_IOMMU_SPAPR_TCE_REMOVE - to create and remove windows.
Up to 2 windows are supported now by the hardware and by this driver.
This changes VFIO_IOMMU_SPAPR_TCE_GET_INFO handler to return additional
information such as a number of supported windows and maximum number
levels of TCE tables.
DDW is added as a capability, not as a SPAPR TCE IOMMU v2 unique feature
as we still want to support v2 on platforms which cannot do DDW for
the sake of TCE acceleration in KVM (coming soon).
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The existing implementation accounts the whole DMA window in
the locked_vm counter. This is going to be worse with multiple
containers and huge DMA windows. Also, real-time accounting would requite
additional tracking of accounted pages due to the page size difference -
IOMMU uses 4K pages and system uses 4K or 64K pages.
Another issue is that actual pages pinning/unpinning happens on every
DMA map/unmap request. This does not affect the performance much now as
we spend way too much time now on switching context between
guest/userspace/host but this will start to matter when we add in-kernel
DMA map/unmap acceleration.
This introduces a new IOMMU type for SPAPR - VFIO_SPAPR_TCE_v2_IOMMU.
New IOMMU deprecates VFIO_IOMMU_ENABLE/VFIO_IOMMU_DISABLE and introduces
2 new ioctls to register/unregister DMA memory -
VFIO_IOMMU_SPAPR_REGISTER_MEMORY and VFIO_IOMMU_SPAPR_UNREGISTER_MEMORY -
which receive user space address and size of a memory region which
needs to be pinned/unpinned and counted in locked_vm.
New IOMMU splits physical pages pinning and TCE table update
into 2 different operations. It requires:
1) guest pages to be registered first
2) consequent map/unmap requests to work only with pre-registered memory.
For the default single window case this means that the entire guest
(instead of 2GB) needs to be pinned before using VFIO.
When a huge DMA window is added, no additional pinning will be
required, otherwise it would be guest RAM + 2GB.
The new memory registration ioctls are not supported by
VFIO_SPAPR_TCE_IOMMU. Dynamic DMA window and in-kernel acceleration
will require memory to be preregistered in order to work.
The accounting is done per the user process.
This advertises v2 SPAPR TCE IOMMU and restricts what the userspace
can do with v1 or v2 IOMMUs.
In order to support memory pre-registration, we need a way to track
the use of every registered memory region and only allow unregistration
if a region is not in use anymore. So we need a way to tell from what
region the just cleared TCE was from.
This adds a userspace view of the TCE table into iommu_table struct.
It contains userspace address, one per TCE entry. The table is only
allocated when the ownership over an IOMMU group is taken which means
it is only used from outside of the powernv code (such as VFIO).
As v2 IOMMU supports IODA2 and pre-IODA2 IOMMUs (which do not support
DDW API), this creates a default DMA window for IODA2 for consistency.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Before the IOMMU user (VFIO) would take control over the IOMMU table
belonging to a specific IOMMU group. This approach did not allow sharing
tables between IOMMU groups attached to the same container.
This introduces a new IOMMU ownership flavour when the user can not
just control the existing IOMMU table but remove/create tables on demand.
If an IOMMU implements take/release_ownership() callbacks, this lets
the user have full control over the IOMMU group. When the ownership
is taken, the platform code removes all the windows so the caller must
create them.
Before returning the ownership back to the platform code, VFIO
unprograms and removes all the tables it created.
This changes IODA2's onwership handler to remove the existing table
rather than manipulating with the existing one. From now on,
iommu_take_ownership() and iommu_release_ownership() are only called
from the vfio_iommu_spapr_tce driver.
Old-style ownership is still supported allowing VFIO to run on older
P5IOC2 and IODA IO controllers.
No change in userspace-visible behaviour is expected. Since it recreates
TCE tables on each ownership change, related kernel traces will appear
more often.
This adds a pnv_pci_ioda2_setup_default_config() which is called
when PE is being configured at boot time and when the ownership is
passed from VFIO to the platform code.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This extends iommu_table_group_ops by a set of callbacks to support
dynamic DMA windows management.
create_table() creates a TCE table with specific parameters.
it receives iommu_table_group to know nodeid in order to allocate
TCE table memory closer to the PHB. The exact format of allocated
multi-level table might be also specific to the PHB model (not
the case now though).
This callback calculated the DMA window offset on a PCI bus from @num
and stores it in a just created table.
set_window() sets the window at specified TVT index + @num on PHB.
unset_window() unsets the window from specified TVT.
This adds a free() callback to iommu_table_ops to free the memory
(potentially a tree of tables) allocated for the TCE table.
create_table() and free() are supposed to be called once per
VFIO container and set_window()/unset_window() are supposed to be
called for every group in a container.
This adds IOMMU capabilities to iommu_table_group such as default
32bit window parameters and others. This makes use of new values in
vfio_iommu_spapr_tce. IODA1/P5IOC2 do not support DDW so they do not
advertise pagemasks to the userspace.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
At the moment writing new TCE value to the IOMMU table fails with EBUSY
if there is a valid entry already. However PAPR specification allows
the guest to write new TCE value without clearing it first.
Another problem this patch is addressing is the use of pool locks for
external IOMMU users such as VFIO. The pool locks are to protect
DMA page allocator rather than entries and since the host kernel does
not control what pages are in use, there is no point in pool locks and
exchange()+put_page(oldtce) is sufficient to avoid possible races.
This adds an exchange() callback to iommu_table_ops which does the same
thing as set() plus it returns replaced TCE and DMA direction so
the caller can release the pages afterwards. The exchange() receives
a physical address unlike set() which receives linear mapping address;
and returns a physical address as the clear() does.
This implements exchange() for P5IOC2/IODA/IODA2. This adds a requirement
for a platform to have exchange() implemented in order to support VFIO.
This replaces iommu_tce_build() and iommu_clear_tce() with
a single iommu_tce_xchg().
This makes sure that TCE permission bits are not set in TCE passed to
IOMMU API as those are to be calculated by platform code from
DMA direction.
This moves SetPageDirty() to the IOMMU code to make it work for both
VFIO ioctl interface in in-kernel TCE acceleration (when it becomes
available later).
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This adds tce_iommu_take_ownership() and tce_iommu_release_ownership
which call in a loop iommu_take_ownership()/iommu_release_ownership()
for every table on the group. As there is just one now, no change in
behaviour is expected.
At the moment the iommu_table struct has a set_bypass() which enables/
disables DMA bypass on IODA2 PHB. This is exposed to POWERPC IOMMU code
which calls this callback when external IOMMU users such as VFIO are
about to get over a PHB.
The set_bypass() callback is not really an iommu_table function but
IOMMU/PE function. This introduces a iommu_table_group_ops struct and
adds take_ownership()/release_ownership() callbacks to it which are
called when an external user takes/releases control over the IOMMU.
This replaces set_bypass() with ownership callbacks as it is not
necessarily just bypass enabling, it can be something else/more
so let's give it more generic name.
The callbacks is implemented for IODA2 only. Other platforms (P5IOC2,
IODA1) will use the old iommu_take_ownership/iommu_release_ownership API.
The following patches will replace iommu_take_ownership/
iommu_release_ownership calls in IODA2 with full IOMMU table release/
create.
As we here and touching bypass control, this removes
pnv_pci_ioda2_setup_bypass_pe() as it does not do much
more compared to pnv_pci_ioda2_set_bypass. This moves tce_bypass_base
initialization to pnv_pci_ioda2_setup_dma_pe.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
So far one TCE table could only be used by one IOMMU group. However
IODA2 hardware allows programming the same TCE table address to
multiple PE allowing sharing tables.
This replaces a single pointer to a group in a iommu_table struct
with a linked list of groups which provides the way of invalidating
TCE cache for every PE when an actual TCE table is updated. This adds
pnv_pci_link_table_and_group() and pnv_pci_unlink_table_and_group()
helpers to manage the list. However without VFIO, it is still going
to be a single IOMMU group per iommu_table.
This changes iommu_add_device() to add a device to a first group
from the group list of a table as it is only called from the platform
init code or PCI bus notifier and at these moments there is only
one group per table.
This does not change TCE invalidation code to loop through all
attached groups in order to simplify this patch and because
it is not really needed in most cases. IODA2 is fixed in a later
patch.
This should cause no behavioural change.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Modern IBM POWERPC systems support multiple (currently two) TCE tables
per IOMMU group (a.k.a. PE). This adds a iommu_table_group container
for TCE tables. Right now just one table is supported.
This defines iommu_table_group struct which stores pointers to
iommu_group and iommu_table(s). This replaces iommu_table with
iommu_table_group where iommu_table was used to identify a group:
- iommu_register_group();
- iommudata of generic iommu_group;
This removes @data from iommu_table as it_table_group provides
same access to pnv_ioda_pe.
For IODA, instead of embedding iommu_table, the new iommu_table_group
keeps pointers to those. The iommu_table structs are allocated
dynamically.
For P5IOC2, both iommu_table_group and iommu_table are embedded into
PE struct. As there is no EEH and SRIOV support for P5IOC2,
iommu_free_table() should not be called on iommu_table struct pointers
so we can keep it embedded in pnv_phb::p5ioc2.
For pSeries, this replaces multiple calls of kzalloc_node() with a new
iommu_pseries_alloc_group() helper and stores the table group struct
pointer into the pci_dn struct. For release, a iommu_table_free_group()
helper is added.
This moves iommu_table struct allocation from SR-IOV code to
the generic DMA initialization code in pnv_pci_ioda_setup_dma_pe and
pnv_pci_ioda2_setup_dma_pe as this is where DMA is actually initialized.
This change is here because those lines had to be changed anyway.
This should cause no behavioural change.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This is to make extended ownership and multiple groups support patches
simpler for review.
This should cause no behavioural change.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This is a pretty mechanical patch to make next patches simpler.
New tce_iommu_unuse_page() helper does put_page() now but it might skip
that after the memory registering patch applied.
As we are here, this removes unnecessary checks for a value returned
by pfn_to_page() as it cannot possibly return NULL.
This moves tce_iommu_disable() later to let tce_iommu_clear() know if
the container has been enabled because if it has not been, then
put_page() must not be called on TCEs from the TCE table. This situation
is not yet possible but it will after KVM acceleration patchset is
applied.
This changes code to work with physical addresses rather than linear
mapping addresses for better code readability. Following patches will
add an xchg() callback for an IOMMU table which will accept/return
physical addresses (unlike current tce_build()) which will eliminate
redundant conversions.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
At the moment DMA map/unmap requests are handled irrespective to
the container's state. This allows the user space to pin memory which
it might not be allowed to pin.
This adds checks to MAP/UNMAP that the container is enabled, otherwise
-EPERM is returned.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
There moves locked pages accounting to helpers.
Later they will be reused for Dynamic DMA windows (DDW).
This reworks debug messages to show the current value and the limit.
This stores the locked pages number in the container so when unlocking
the iommu table pointer won't be needed. This does not have an effect
now but it will with the multiple tables per container as then we will
allow attaching/detaching groups on fly and we may end up having
a container with no group attached but with the counter incremented.
While we are here, update the comment explaining why RLIMIT_MEMLOCK
might be required to be bigger than the guest RAM. This also prints
pid of the current process in pr_warn/pr_debug.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This makes use of the it_page_size from the iommu_table struct
as page size can differ.
This replaces missing IOMMU_PAGE_SHIFT macro in commented debug code
as recently introduced IOMMU_PAGE_XXX macros do not include
IOMMU_PAGE_SHIFT.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This checks that the TCE table page size is not bigger that the size of
a page we just pinned and going to put its physical address to the table.
Otherwise the hardware gets unwanted access to physical memory between
the end of the actual page and the end of the aligned up TCE page.
Since compound_order() and compound_head() work correctly on non-huge
pages, there is no need for additional check whether the page is huge.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This moves page pinning (get_user_pages_fast()/put_page()) code out of
the platform IOMMU code and puts it to VFIO IOMMU driver where it belongs
to as the platform code does not deal with page pinning.
This makes iommu_take_ownership()/iommu_release_ownership() deal with
the IOMMU table bitmap only.
This removes page unpinning from iommu_take_ownership() as the actual
TCE table might contain garbage and doing put_page() on it is undefined
behaviour.
Besides the last part, the rest of the patch is mechanical.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
[aw: for the vfio related changes]
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Testing the driver for a PCI device is racy, it can be all but
complete in the release path and still report the driver as ours.
Therefore we can't trust drvdata to be valid. This race can sometimes
be seen when one port of a multifunction device is being unbound from
the vfio-pci driver while another function is being released by the
user and attempting a bus reset. The device in the remove path is
found as a dependent device for the bus reset of the release path
device, the driver is still set to vfio-pci, but the drvdata has
already been cleared, resulting in a null pointer dereference.
To resolve this, fix vfio_device_get_from_dev() to not take the
dev_get_drvdata() shortcut and instead traverse through the
iommu_group, vfio_group, vfio_device path to get a reference we
can trust. Once we have that reference, we know the device isn't
in transition and we can test to make sure the driver is still what
we expect, so that we don't interfere with devices we don't own.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The ARM SMMUv3 driver is compatible with the notion of a type-1 IOMMU in
VFIO.
This patch allows VFIO_IOMMU_TYPE1 to be selected if ARM_SMMU_V3=y.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The patch adds one more EEH sub-command (VFIO_EEH_PE_INJECT_ERR)
to inject the specified EEH error, which is represented by
(struct vfio_eeh_pe_err), to the indicated PE for testing purpose.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Commit 13060b64b8 ("vfio: Add and use device request op for vfio
bus drivers") incorrectly makes use of an interruptible timeout.
When interrupted, the signal remains pending resulting in subsequent
timeouts occurring instantly. This makes the loop spin at a much
higher rate than intended.
Instead of making this completely non-interruptible, we can change
this into a sort of interruptible-once behavior and use the "once"
to log debug information. The driver API doesn't allow us to abort
and return an error code.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Fixes: 13060b64b8
Cc: stable@vger.kernel.org # v4.0
Log some clues indicating whether the user is receiving device
request interfaces or not listening. This can help indicate why a
driver unbind is blocked or explain why QEMU automatically unplugged
a device from the VM.
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>
An unintended consequence of commit 42ac9bd18d ("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>
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>
This adds a missing break statement to VFIO_DEVICE_SET_IRQS handler
without which vfio_pci_set_err_trigger() would never be called.
While we are here, add another "break" to VFIO_PCI_REQ_IRQ_INDEX case
so if we add more indexes later, we won't miss it.
Fixes: 6140a8f562 ("vfio-pci: Add device request interface")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Userspace can opt to receive a device request notification,
indicating that the device should be released. This is setup
the same way as the error IRQ and also supports eventfd signaling.
Future support may forcefully remove the device from the user if
the request is ignored.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We want another single vector IRQ index to support signaling of
the device request to userspace. Generalize the error reporting
IRQ index to avoid code duplication.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
When a request is made to unbind a device from a vfio bus driver,
we need to wait for the device to become unused, ie. for userspace
to release the device. However, we have a long standing TODO in
the code to do something proactive to make that happen. To enable
this, we add a request callback on the vfio bus driver struct,
which is intended to signal the user through the vfio device
interface to release the device. Instead of passively waiting for
the device to become unused, we can now pester the user to give
it up.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Move the iommu_group reference from the device to the vfio_group.
This ensures that the iommu_group persists as long as the vfio_group
remains. This can be important if all of the device from an
iommu_group are removed, but we still have an outstanding vfio_group
reference; we can still walk the empty list of devices.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There's a small window between the vfio bus driver calling
vfio_del_group_dev() and the device being completely unbound where
the vfio group appears to be non-viable. This creates a race for
users like QEMU/KVM where the kvm-vfio module tries to get an
external reference to the group in order to match and release an
existing reference, while the device is potentially being removed
from the vfio bus driver. If the group is momentarily non-viable,
kvm-vfio may not be able to release the group reference until VM
shutdown, making the group unusable until that point.
Bridge the gap between device removal from the group and completion
of the driver unbind by tracking it in a list. The device is added
to the list before the bus driver reference is released and removed
using the existing unbind notifier.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
IOMMU operations can be expensive and it's not very difficult for a
user to give us a lot of work to do for a map or unmap operation.
Killing a large VM will vfio assigned devices can result in soft
lockups and IOMMU tracing shows that we can easily spend 80% of our
time with need-resched set. A sprinkling of conf_resched() calls
after map and unmap calls has a very tiny affect on performance
while resulting in traces with <1% of calls overflowing into needs-
resched.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We currently map invalid and reserved pages, such as often occur from
mapping MMIO regions of a VM through the IOMMU, using single pages.
There's really no reason we can't instead follow the methodology we
use for normal pages and find the largest possible physically
contiguous chunk for mapping. The only difference is that we don't
do locked memory accounting for these since they're not back by RAM.
In most applications this will be a very minor improvement, but when
graphics and GPGPU devices are in play, MMIO BARs become non-trivial.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
When unmapping DMA entries we try to rely on the IOMMU API behavior
that allows the IOMMU to unmap a larger area than requested, up to
the size of the original mapping. This works great when the IOMMU
supports superpages *and* they're in use. Otherwise, each PAGE_SIZE
increment is unmapped separately, resulting in poor performance.
Instead we can use the IOVA-to-physical-address translation provided
by the IOMMU API and unmap using the largest contiguous physical
memory chunk available, which is also how vfio/type1 would have
mapped the region. For a synthetic 1TB guest VM mapping and shutdown
test on Intel VT-d (2M IOMMU pagesize support), this achieves about
a 30% overall improvement mapping standard 4K pages, regardless of
IOMMU superpage enabling, and about a 40% improvement mapping 2M
hugetlbfs pages when IOMMU superpages are not available. Hugetlbfs
with IOMMU superpages enabled is effectively unchanged.
Unfortunately the same algorithm does not work well on IOMMUs with
fine-grained superpages, like AMD-Vi, costing about 25% extra since
the IOMMU will automatically unmap any power-of-two contiguous
mapping we've provided it. We add a routine and a domain flag to
detect this feature, leaving AMD-Vi unaffected by this unmap
optimization.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Current vfio-pci just supports normal pci device, so vfio_pci_probe() will
return if the pci device is not a normal device. While current code makes a
mistake. PCI_HEADER_TYPE is the offset in configuration space of the device
type, but we use this value to mask the type value.
This patch fixs this by do the check directly on the pci_dev->hdr_type.
Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: stable@vger.kernel.org # v3.6+
- s390 support (Frank Blaschka)
- Enable iommu-type1 for ARM SMMU (Will Deacon)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=1L2V
-----END PGP SIGNATURE-----
Merge tag 'vfio-v3.19-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
- s390 support (Frank Blaschka)
- Enable iommu-type1 for ARM SMMU (Will Deacon)
* tag 'vfio-v3.19-rc1' of git://github.com/awilliam/linux-vfio:
drivers/vfio: allow type-1 IOMMU instantiation on top of an ARM SMMU
vfio: make vfio run on s390
Rename write_msi_msg() to pci_write_msi_msg() to mark it as PCI
specific.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The ARM SMMU driver is compatible with the notion of a type-1 IOMMU in
VFIO.
This patch allows VFIO_IOMMU_TYPE1 to be selected if ARM_SMMU=y.
Signed-off-by: Will Deacon <will.deacon@arm.com>
[aw: update for existing S390 patch]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
add Kconfig switch to hide INTx
add Kconfig switch to let vfio announce PCI BARs are not mapable
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This pull-request includes:
* Change in the IOMMU-API to convert the former iommu_domain_capable
function to just iommu_capable
* Various fixes in handling RMRR ranges for the VT-d driver (one fix
requires a device driver core change which was acked
by Greg KH)
* The AMD IOMMU driver now assigns and deassigns complete alias groups
to fix issues with devices using the wrong PCI request-id
* MMU-401 support for the ARM SMMU driver
* Multi-master IOMMU group support for the ARM SMMU driver
* Various other small fixes all over the place
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=OMOt
-----END PGP SIGNATURE-----
Merge tag 'iommu-updates-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
"This pull-request includes:
- change in the IOMMU-API to convert the former iommu_domain_capable
function to just iommu_capable
- various fixes in handling RMRR ranges for the VT-d driver (one fix
requires a device driver core change which was acked by Greg KH)
- the AMD IOMMU driver now assigns and deassigns complete alias
groups to fix issues with devices using the wrong PCI request-id
- MMU-401 support for the ARM SMMU driver
- multi-master IOMMU group support for the ARM SMMU driver
- various other small fixes all over the place"
* tag 'iommu-updates-v3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (41 commits)
iommu/vt-d: Work around broken RMRR firmware entries
iommu/vt-d: Store bus information in RMRR PCI device path
iommu/vt-d: Only remove domain when device is removed
driver core: Add BUS_NOTIFY_REMOVED_DEVICE event
iommu/amd: Fix devid mapping for ivrs_ioapic override
iommu/irq_remapping: Fix the regression of hpet irq remapping
iommu: Fix bus notifier breakage
iommu/amd: Split init_iommu_group() from iommu_init_device()
iommu: Rework iommu_group_get_for_pci_dev()
iommu: Make of_device_id array const
amd_iommu: do not dereference a NULL pointer address.
iommu/omap: Remove omap_iommu unused owner field
iommu: Remove iommu_domain_has_cap() API function
IB/usnic: Convert to use new iommu_capable() API function
vfio: Convert to use new iommu_capable() API function
kvm: iommu: Convert to use new iommu_capable() API function
iommu/tegra: Convert to iommu_capable() API function
iommu/msm: Convert to iommu_capable() API function
iommu/vt-d: Convert to iommu_capable() API function
iommu/fsl: Convert to iommu_capable() API function
...
Locking both the remove() and release() path results in a deadlock
that should have been obvious. To fix this we can get and hold the
vfio_device reference as we evaluate whether to do a bus/slot reset.
This will automatically block any remove() calls, allowing us to
remove the explict lock. Fixes 61d792562b.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: stable@vger.kernel.org [3.17]
The function should have been exported with EXPORT_SYMBOL_GPL()
as part of commit 92d18a6851 ("drivers/vfio: Fix EEH build error").
Suggested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The MSIx vector table lives in device memory, which may be cleared as
part of a backdoor device reset. This is the case on the IBM IPR HBA
when the BIST is run on the device. When assigned to a QEMU guest,
the guest driver does a pci_save_state(), issues a BIST, then does a
pci_restore_state(). The BIST clears the MSIx vector table, but due
to the way interrupts are configured the pci_restore_state() does not
restore the vector table as expected. Eventually this results in an
EEH error on Power platforms when the device attempts to signal an
interrupt with the zero'd table entry.
Fix the problem by restoring the host cached MSI message prior to
enabling each vector.
Reported-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
VFIO allows devices to be safely handed off to userspace by putting
them behind an IOMMU configured to ensure DMA and interrupt isolation.
This enables userspace KVM clients, such as kvmtool and qemu, to further
map the device into a virtual machine.
With IOMMUs such as the ARM SMMU, it is then possible to provide SMMU
translation services to the guest operating system, which are nested
with the existing translation installed by VFIO. However, enabling this
feature means that the IOMMU driver must be informed that the VFIO domain
is being created for the purposes of nested translation.
This patch adds a new IOMMU type (VFIO_TYPE1_NESTING_IOMMU) to the VFIO
type-1 driver. The new IOMMU type acts identically to the
VFIO_TYPE1v2_IOMMU type, but additionally sets the DOMAIN_ATTR_NESTING
attribute on its IOMMU domains.
Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In PCIe r1.0, sec 5.10.2, bit 0 of the Uncorrectable Error Status, Mask,
and Severity Registers was for "Training Error." In PCIe r1.1, sec 7.10.2,
bit 0 was redefined to be "Undefined."
Rename PCI_ERR_UNC_TRAIN to PCI_ERR_UNC_UND to reflect this change.
No functional change.
[bhelgaas: changelog]
Signed-off-by: Chen, Gong <gong.chen@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The existing vfio_pci_open() fails upon error returned from
vfio_spapr_pci_eeh_open(), which breaks POWER7's P5IOC2 PHB
support which this patch brings back.
The patch fixes the issue by dropping the return value of
vfio_spapr_pci_eeh_open().
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The VFIO related components could be built as dynamic modules.
Unfortunately, CONFIG_EEH can't be configured to "m". The patch
fixes the build errors when configuring VFIO related components
as dynamic modules as follows:
CC [M] drivers/vfio/vfio_iommu_spapr_tce.o
In file included from drivers/vfio/vfio.c:33:0:
include/linux/vfio.h:101:43: warning: ‘struct pci_dev’ declared \
inside parameter list [enabled by default]
:
WRAP arch/powerpc/boot/zImage.pseries
WRAP arch/powerpc/boot/zImage.maple
WRAP arch/powerpc/boot/zImage.pmac
WRAP arch/powerpc/boot/zImage.epapr
MODPOST 1818 modules
ERROR: ".vfio_spapr_iommu_eeh_ioctl" [drivers/vfio/vfio_iommu_spapr_tce.ko]\
undefined!
ERROR: ".vfio_spapr_pci_eeh_open" [drivers/vfio/pci/vfio-pci.ko] undefined!
ERROR: ".vfio_spapr_pci_eeh_release" [drivers/vfio/pci/vfio-pci.ko] undefined!
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Each time a device is released, mark whether a local reset was
successful or whether a bus/slot reset is needed. If a reset is
needed and all of the affected devices are bound to vfio-pci and
unused, allow the reset. This is most useful when the userspace
driver is killed and releases all the devices in an unclean state,
such as when a QEMU VM quits.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Serializing open/release allows us to fix a refcnt error if we fail
to enable the device and lets us prevent devices from being unbound
or opened, giving us an opportunity to do bus resets on release. No
restriction added to serialize binding devices to vfio-pci while the
mutex is held though.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Our current open/release path looks like this:
vfio_pci_open
vfio_pci_enable
pci_enable_device
pci_save_state
pci_store_saved_state
vfio_pci_release
vfio_pci_disable
pci_disable_device
pci_restore_state
pci_enable_device() doesn't modify PCI_COMMAND_MASTER, so if a device
comes to us with it enabled, it persists through the open and gets
stored as part of the device saved state. We then restore that saved
state when released, which can allow the device to attempt to continue
to do DMA. When the group is disconnected from the domain, this will
get caught by the IOMMU, but if there are other devices in the group,
the device may continue running and interfere with the user. Even in
the former case, IOMMUs don't necessarily behave well and a stream of
blocked DMA can result in unpleasant behavior on the host.
Explicitly disable Bus Master as we're enabling the device and
slightly re-work release to make sure that pci_disable_device() is
the last thing that touches the device.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The patch adds new IOCTL commands for sPAPR VFIO container device
to support EEH functionality for PCI devices, which have been passed
through from host to somebody else via VFIO.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Alexander Graf <agraf@suse.de>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
According PCI local bus specification, the register of Message
Control for MSI (offset: 2, length: 2) has bit#0 to enable or
disable MSI logic and it shouldn't be part contributing to the
calculation of MSI interrupt count. The patch fixes the issue.
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Coverity reports use of a tained scalar used as a loop boundary.
For the most part, any values passed from userspace for a DMA mapping
size, IOVA, or virtual address are valid, with some alignment
constraints. The size is ultimately bound by how many pages the user
is able to lock, IOVA is tested by the IOMMU driver when doing a map,
and the virtual address needs to pass get_user_pages. The only
problem I can find is that we do expect the __u64 user values to fit
within our variables, which might not happen on 32bit platforms. Add
a test for this and return error on overflow. Also propagate use of
the type-correct local variables throughout the function.
The above also points to the 'end' variable, which can be zero if
we're operating at the very top of the address space. We try to
account for this, but our loop botches it. Rework the loop to use
the remaining size as our loop condition rather than the IOVA vs end.
Detected by Coverity: CID 714659
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There's nothing we can do different if pci_load_and_free_saved_state()
fails, other than maybe print some log message, but the actual re-load
of the state is an unnecessary step here since we've only just saved
it. We can cleanup a coverity warning and eliminate the unnecessary
step by freeing the state ourselves.
Detected by Coverity: CID 753101
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
When sizing the TPH capability we store the register containing the
table size into the 'dword' variable, but then use the uninitialized
'byte' variable to analyze the size. The table size is also actually
reported as an N-1 value, so correct sizing to account for this.
The round_up() for both TPH and DPA is unnecessary, remove it.
Detected by Coverity: CID 714665 & 715156
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
So there is no point in checking its return value, which will soon
disappear.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
- Allow the vfio-type1 IOMMU to support multiple domains within a container
- Plumb path to query whether all domains are cache-coherent
- Wire query into kvm-vfio device to avoid KVM x86 WBINVD emulation
- Always select CONFIG_ANON_INODES, vfio depends on it (Arnd)
The first patch also makes the vfio-type1 IOMMU driver completely independent
of the bus_type of the devices it's handling, which enables it to be used for
both vfio-pci and a future vfio-platform (and hopefully combinations involving
both simultaneously).
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=mnzO
-----END PGP SIGNATURE-----
Merge tag 'vfio-v3.15-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
"VFIO updates for v3.15 include:
- Allow the vfio-type1 IOMMU to support multiple domains within a
container
- Plumb path to query whether all domains are cache-coherent
- Wire query into kvm-vfio device to avoid KVM x86 WBINVD emulation
- Always select CONFIG_ANON_INODES, vfio depends on it (Arnd)
The first patch also makes the vfio-type1 IOMMU driver completely
independent of the bus_type of the devices it's handling, which
enables it to be used for both vfio-pci and a future vfio-platform
(and hopefully combinations involving both simultaneously)"
* tag 'vfio-v3.15-rc1' of git://github.com/awilliam/linux-vfio:
vfio: always select ANON_INODES
kvm/vfio: Support for DMA coherent IOMMUs
vfio: Add external user check extension interface
vfio/type1: Add extension to test DMA cache coherence of IOMMU
vfio/iommu_type1: Multi-IOMMU domain support
Enumeration
- Increment max correctly in pci_scan_bridge() (Andreas Noever)
- Clarify the "scan anyway" comment in pci_scan_bridge() (Andreas Noever)
- Assign CardBus bus number only during the second pass (Andreas Noever)
- Use request_resource_conflict() instead of insert_ for bus numbers (Andreas Noever)
- Make sure bus number resources stay within their parents bounds (Andreas Noever)
- Remove pci_fixup_parent_subordinate_busnr() (Andreas Noever)
- Check for child busses which use more bus numbers than allocated (Andreas Noever)
- Don't scan random busses in pci_scan_bridge() (Andreas Noever)
- x86: Drop pcibios_scan_root() check for bus already scanned (Bjorn Helgaas)
- x86: Use pcibios_scan_root() instead of pci_scan_bus_with_sysdata() (Bjorn Helgaas)
- x86: Use pcibios_scan_root() instead of pci_scan_bus_on_node() (Bjorn Helgaas)
- x86: Merge pci_scan_bus_on_node() into pcibios_scan_root() (Bjorn Helgaas)
- x86: Drop return value of pcibios_scan_root() (Bjorn Helgaas)
NUMA
- x86: Add x86_pci_root_bus_node() to look up NUMA node from PCI bus (Bjorn Helgaas)
- x86: Use x86_pci_root_bus_node() instead of get_mp_bus_to_node() (Bjorn Helgaas)
- x86: Remove mp_bus_to_node[], set_mp_bus_to_node(), get_mp_bus_to_node() (Bjorn Helgaas)
- x86: Use NUMA_NO_NODE, not -1, for unknown node (Bjorn Helgaas)
- x86: Remove acpi_get_pxm() usage (Bjorn Helgaas)
- ia64: Use NUMA_NO_NODE, not MAX_NUMNODES, for unknown node (Bjorn Helgaas)
- ia64: Remove acpi_get_pxm() usage (Bjorn Helgaas)
- ACPI: Fix acpi_get_node() prototype (Bjorn Helgaas)
Resource management
- i2o: Fix and refactor PCI space allocation (Bjorn Helgaas)
- Add resource_contains() (Bjorn Helgaas)
- Add %pR support for IORESOURCE_UNSET (Bjorn Helgaas)
- Mark resources as IORESOURCE_UNSET if we can't assign them (Bjorn Helgaas)
- Don't clear IORESOURCE_UNSET when updating BAR (Bjorn Helgaas)
- Check IORESOURCE_UNSET before updating BAR (Bjorn Helgaas)
- Don't try to claim IORESOURCE_UNSET resources (Bjorn Helgaas)
- Mark 64-bit resource as IORESOURCE_UNSET if we only support 32-bit (Bjorn Helgaas)
- Don't enable decoding if BAR hasn't been assigned an address (Bjorn Helgaas)
- Add "weak" generic pcibios_enable_device() implementation (Bjorn Helgaas)
- alpha, microblaze, sh, sparc, tile: Use default pcibios_enable_device() (Bjorn Helgaas)
- s390: Use generic pci_enable_resources() (Bjorn Helgaas)
- Don't check resource_size() in pci_bus_alloc_resource() (Bjorn Helgaas)
- Set type in __request_region() (Bjorn Helgaas)
- Check all IORESOURCE_TYPE_BITS in pci_bus_alloc_from_region() (Bjorn Helgaas)
- Change pci_bus_alloc_resource() type_mask to unsigned long (Bjorn Helgaas)
- Log IDE resource quirk in dmesg (Bjorn Helgaas)
- Revert "[PATCH] Insert GART region into resource map" (Bjorn Helgaas)
PCI device hotplug
- Make check_link_active() non-static (Rajat Jain)
- Use link change notifications for hot-plug and removal (Rajat Jain)
- Enable link state change notifications (Rajat Jain)
- Don't disable the link permanently during removal (Rajat Jain)
- Don't check adapter or latch status while disabling (Rajat Jain)
- Disable link notification across slot reset (Rajat Jain)
- Ensure very fast hotplug events are also processed (Rajat Jain)
- Add hotplug_lock to serialize hotplug events (Rajat Jain)
- Remove a non-existent card, regardless of "surprise" capability (Rajat Jain)
- Don't turn slot off when hot-added device already exists (Yijing Wang)
MSI
- Keep pci_enable_msi() documentation (Alexander Gordeev)
- ahci: Fix broken single MSI fallback (Alexander Gordeev)
- ahci, vfio: Use pci_enable_msi_range() (Alexander Gordeev)
- Check kmalloc() return value, fix leak of name (Greg Kroah-Hartman)
- Fix leak of msi_attrs (Greg Kroah-Hartman)
- Fix pci_msix_vec_count() htmldocs failure (Masanari Iida)
Virtualization
- Device-specific ACS support (Alex Williamson)
Freescale i.MX6
- Wait for retraining (Marek Vasut)
Marvell MVEBU
- Use Device ID and revision from underlying endpoint (Andrew Lunn)
- Fix incorrect size for PCI aperture resources (Jason Gunthorpe)
- Call request_resource() on the apertures (Jason Gunthorpe)
- Fix potential issue in range parsing (Jean-Jacques Hiblot)
Renesas R-Car
- Check platform_get_irq() return code (Ben Dooks)
- Add error interrupt handling (Ben Dooks)
- Fix bridge logic configuration accesses (Ben Dooks)
- Register each instance independently (Magnus Damm)
- Break out window size handling (Magnus Damm)
- Make the Kconfig dependencies more generic (Magnus Damm)
Synopsys DesignWare
- Fix RC BAR to be single 64-bit non-prefetchable memory (Mohit Kumar)
Miscellaneous
- Remove unused SR-IOV VF Migration support (Bjorn Helgaas)
- Enable INTx if BIOS left them disabled (Bjorn Helgaas)
- Fix hex vs decimal typo in cpqhpc_probe() (Dan Carpenter)
- Clean up par-arch object file list (Liviu Dudau)
- Set IORESOURCE_ROM_SHADOW only for the default VGA device (Sander Eikelenboom)
- ACPI, ARM, drm, powerpc, pcmcia, PCI: Use list_for_each_entry() for bus traversal (Yijing Wang)
- Fix pci_bus_b() build failure (Paul Gortmaker)
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)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=3mNS
-----END PGP SIGNATURE-----
Merge tag 'pci-v3.15-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI changes from Bjorn Helgaas:
"Enumeration
- Increment max correctly in pci_scan_bridge() (Andreas Noever)
- Clarify the "scan anyway" comment in pci_scan_bridge() (Andreas Noever)
- Assign CardBus bus number only during the second pass (Andreas Noever)
- Use request_resource_conflict() instead of insert_ for bus numbers (Andreas Noever)
- Make sure bus number resources stay within their parents bounds (Andreas Noever)
- Remove pci_fixup_parent_subordinate_busnr() (Andreas Noever)
- Check for child busses which use more bus numbers than allocated (Andreas Noever)
- Don't scan random busses in pci_scan_bridge() (Andreas Noever)
- x86: Drop pcibios_scan_root() check for bus already scanned (Bjorn Helgaas)
- x86: Use pcibios_scan_root() instead of pci_scan_bus_with_sysdata() (Bjorn Helgaas)
- x86: Use pcibios_scan_root() instead of pci_scan_bus_on_node() (Bjorn Helgaas)
- x86: Merge pci_scan_bus_on_node() into pcibios_scan_root() (Bjorn Helgaas)
- x86: Drop return value of pcibios_scan_root() (Bjorn Helgaas)
NUMA
- x86: Add x86_pci_root_bus_node() to look up NUMA node from PCI bus (Bjorn Helgaas)
- x86: Use x86_pci_root_bus_node() instead of get_mp_bus_to_node() (Bjorn Helgaas)
- x86: Remove mp_bus_to_node[], set_mp_bus_to_node(), get_mp_bus_to_node() (Bjorn Helgaas)
- x86: Use NUMA_NO_NODE, not -1, for unknown node (Bjorn Helgaas)
- x86: Remove acpi_get_pxm() usage (Bjorn Helgaas)
- ia64: Use NUMA_NO_NODE, not MAX_NUMNODES, for unknown node (Bjorn Helgaas)
- ia64: Remove acpi_get_pxm() usage (Bjorn Helgaas)
- ACPI: Fix acpi_get_node() prototype (Bjorn Helgaas)
Resource management
- i2o: Fix and refactor PCI space allocation (Bjorn Helgaas)
- Add resource_contains() (Bjorn Helgaas)
- Add %pR support for IORESOURCE_UNSET (Bjorn Helgaas)
- Mark resources as IORESOURCE_UNSET if we can't assign them (Bjorn Helgaas)
- Don't clear IORESOURCE_UNSET when updating BAR (Bjorn Helgaas)
- Check IORESOURCE_UNSET before updating BAR (Bjorn Helgaas)
- Don't try to claim IORESOURCE_UNSET resources (Bjorn Helgaas)
- Mark 64-bit resource as IORESOURCE_UNSET if we only support 32-bit (Bjorn Helgaas)
- Don't enable decoding if BAR hasn't been assigned an address (Bjorn Helgaas)
- Add "weak" generic pcibios_enable_device() implementation (Bjorn Helgaas)
- alpha, microblaze, sh, sparc, tile: Use default pcibios_enable_device() (Bjorn Helgaas)
- s390: Use generic pci_enable_resources() (Bjorn Helgaas)
- Don't check resource_size() in pci_bus_alloc_resource() (Bjorn Helgaas)
- Set type in __request_region() (Bjorn Helgaas)
- Check all IORESOURCE_TYPE_BITS in pci_bus_alloc_from_region() (Bjorn Helgaas)
- Change pci_bus_alloc_resource() type_mask to unsigned long (Bjorn Helgaas)
- Log IDE resource quirk in dmesg (Bjorn Helgaas)
- Revert "[PATCH] Insert GART region into resource map" (Bjorn Helgaas)
PCI device hotplug
- Make check_link_active() non-static (Rajat Jain)
- Use link change notifications for hot-plug and removal (Rajat Jain)
- Enable link state change notifications (Rajat Jain)
- Don't disable the link permanently during removal (Rajat Jain)
- Don't check adapter or latch status while disabling (Rajat Jain)
- Disable link notification across slot reset (Rajat Jain)
- Ensure very fast hotplug events are also processed (Rajat Jain)
- Add hotplug_lock to serialize hotplug events (Rajat Jain)
- Remove a non-existent card, regardless of "surprise" capability (Rajat Jain)
- Don't turn slot off when hot-added device already exists (Yijing Wang)
MSI
- Keep pci_enable_msi() documentation (Alexander Gordeev)
- ahci: Fix broken single MSI fallback (Alexander Gordeev)
- ahci, vfio: Use pci_enable_msi_range() (Alexander Gordeev)
- Check kmalloc() return value, fix leak of name (Greg Kroah-Hartman)
- Fix leak of msi_attrs (Greg Kroah-Hartman)
- Fix pci_msix_vec_count() htmldocs failure (Masanari Iida)
Virtualization
- Device-specific ACS support (Alex Williamson)
Freescale i.MX6
- Wait for retraining (Marek Vasut)
Marvell MVEBU
- Use Device ID and revision from underlying endpoint (Andrew Lunn)
- Fix incorrect size for PCI aperture resources (Jason Gunthorpe)
- Call request_resource() on the apertures (Jason Gunthorpe)
- Fix potential issue in range parsing (Jean-Jacques Hiblot)
Renesas R-Car
- Check platform_get_irq() return code (Ben Dooks)
- Add error interrupt handling (Ben Dooks)
- Fix bridge logic configuration accesses (Ben Dooks)
- Register each instance independently (Magnus Damm)
- Break out window size handling (Magnus Damm)
- Make the Kconfig dependencies more generic (Magnus Damm)
Synopsys DesignWare
- Fix RC BAR to be single 64-bit non-prefetchable memory (Mohit Kumar)
Miscellaneous
- Remove unused SR-IOV VF Migration support (Bjorn Helgaas)
- Enable INTx if BIOS left them disabled (Bjorn Helgaas)
- Fix hex vs decimal typo in cpqhpc_probe() (Dan Carpenter)
- Clean up par-arch object file list (Liviu Dudau)
- Set IORESOURCE_ROM_SHADOW only for the default VGA device (Sander Eikelenboom)
- ACPI, ARM, drm, powerpc, pcmcia, PCI: Use list_for_each_entry() for bus traversal (Yijing Wang)
- Fix pci_bus_b() build failure (Paul Gortmaker)"
* tag 'pci-v3.15-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (108 commits)
Revert "[PATCH] Insert GART region into resource map"
PCI: Log IDE resource quirk in dmesg
PCI: Change pci_bus_alloc_resource() type_mask to unsigned long
PCI: Check all IORESOURCE_TYPE_BITS in pci_bus_alloc_from_region()
resources: Set type in __request_region()
PCI: Don't check resource_size() in pci_bus_alloc_resource()
s390/PCI: Use generic pci_enable_resources()
tile PCI RC: Use default pcibios_enable_device()
sparc/PCI: Use default pcibios_enable_device() (Leon only)
sh/PCI: Use default pcibios_enable_device()
microblaze/PCI: Use default pcibios_enable_device()
alpha/PCI: Use default pcibios_enable_device()
PCI: Add "weak" generic pcibios_enable_device() implementation
PCI: Don't enable decoding if BAR hasn't been assigned an address
PCI: Enable INTx in pci_reenable_device() only when MSI/MSI-X not enabled
PCI: Mark 64-bit resource as IORESOURCE_UNSET if we only support 32-bit
PCI: Don't try to claim IORESOURCE_UNSET resources
PCI: Check IORESOURCE_UNSET before updating BAR
PCI: Don't clear IORESOURCE_UNSET when updating BAR
PCI: Mark resources as IORESOURCE_UNSET if we can't assign them
...
Conflicts:
arch/x86/include/asm/topology.h
drivers/ata/ahci.c
The vfio code cannot be built when CONFIG_ANON_INODES is
disabled, so this enforces the symbol to be enabled through
Kconfig.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Commit bf6bddf192 ("mm: introduce compaction and migration for
ballooned pages") introduces page_count(page) into memory compaction
which dereferences page->first_page if PageTail(page).
This results in a very rare NULL pointer dereference on the
aforementioned page_count(page). Indeed, anything that does
compound_head(), including page_count() is susceptible to racing with
prep_compound_page() and seeing a NULL or dangling page->first_page
pointer.
This patch uses Andrea's implementation of compound_trans_head() that
deals with such a race and makes it the default compound_head()
implementation. This includes a read memory barrier that ensures that
if PageTail(head) is true that we return a head page that is neither
NULL nor dangling. The patch then adds a store memory barrier to
prep_compound_page() to ensure page->first_page is set.
This is the safest way to ensure we see the head page that we are
expecting, PageTail(page) is already in the unlikely() path and the
memory barriers are unfortunately required.
Hugetlbfs is the exception, we don't enforce a store memory barrier
during init since no race is possible.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Holger Kiehl <Holger.Kiehl@dwd.de>
Cc: Christoph Lameter <cl@linux.com>
Cc: Rafael Aquini <aquini@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This lets us check extensions, particularly VFIO_DMA_CC_IOMMU using
the external user interface, allowing KVM to probe IOMMU coherency.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that the type1 IOMMU backend can support IOMMU_CACHE, we need to
be able to test whether coherency is currently enforced. Add an
extension for this.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We currently have a problem that we cannot support advanced features
of an IOMMU domain (ex. IOMMU_CACHE), because we have no guarantee
that those features will be supported by all of the hardware units
involved with the domain over its lifetime. For instance, the Intel
VT-d architecture does not require that all DRHDs support snoop
control. If we create a domain based on a device behind a DRHD that
does support snoop control and enable SNP support via the IOMMU_CACHE
mapping option, we cannot then add a device behind a DRHD which does
not support snoop control or we'll get reserved bit faults from the
SNP bit in the pagetables. To add to the complexity, we can't know
the properties of a domain until a device is attached.
We could pass this problem off to userspace and require that a
separate vfio container be used, but we don't know how to handle page
accounting in that case. How do we know that a page pinned in one
container is the same page as a different container and avoid double
billing the user for the page.
The solution is therefore to support multiple IOMMU domains per
container. In the majority of cases, only one domain will be required
since hardware is typically consistent within a system. However, this
provides us the ability to validate compatibility of domains and
support mixed environments where page table flags can be different
between domains.
To do this, our DMA tracking needs to change. We currently try to
coalesce user mappings into as few tracking entries as possible. The
problem then becomes that we lose granularity of user mappings. We've
never guaranteed that a user is able to unmap at a finer granularity
than the original mapping, but we must honor the granularity of the
original mapping. This coalescing code is therefore removed, allowing
only unmaps covering complete maps. The change in accounting is
fairly small here, a typical QEMU VM will start out with roughly a
dozen entries, so it's arguable if this coalescing was ever needed.
We also move IOMMU domain creation to the point where a group is
attached to the container. An interesting side-effect of this is that
we now have access to the device at the time of domain creation and
can probe the devices within the group to determine the bus_type.
This finally makes vfio_iommu_type1 completely device/bus agnostic.
In fact, each IOMMU domain can host devices on different buses managed
by different physical IOMMUs, and present a single DMA mapping
interface to the user. When a new domain is created, mappings are
replayed to bring the IOMMU pagetables up to the state of the current
container. And of course, DMA mapping and unmapping automatically
traverse all of the configured IOMMU domains.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: Varun Sethi <Varun.Sethi@freescale.com>
pci_enable_msix() and pci_enable_msi_block() have been deprecated; use
pci_enable_msix_range() and pci_enable_msi_range() instead.
[bhelgaas: changelog]
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Pull powerpc updates from Ben Herrenschmidt:
"So here's my next branch for powerpc. A bit late as I was on vacation
last week. It's mostly the same stuff that was in next already, I
just added two patches today which are the wiring up of lockref for
powerpc, which for some reason fell through the cracks last time and
is trivial.
The highlights are, in addition to a bunch of bug fixes:
- Reworked Machine Check handling on kernels running without a
hypervisor (or acting as a hypervisor). Provides hooks to handle
some errors in real mode such as TLB errors, handle SLB errors,
etc...
- Support for retrieving memory error information from the service
processor on IBM servers running without a hypervisor and routing
them to the memory poison infrastructure.
- _PAGE_NUMA support on server processors
- 32-bit BookE relocatable kernel support
- FSL e6500 hardware tablewalk support
- A bunch of new/revived board support
- FSL e6500 deeper idle states and altivec powerdown support
You'll notice a generic mm change here, it has been acked by the
relevant authorities and is a pre-req for our _PAGE_NUMA support"
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (121 commits)
powerpc: Implement arch_spin_is_locked() using arch_spin_value_unlocked()
powerpc: Add support for the optimised lockref implementation
powerpc/powernv: Call OPAL sync before kexec'ing
powerpc/eeh: Escalate error on non-existing PE
powerpc/eeh: Handle multiple EEH errors
powerpc: Fix transactional FP/VMX/VSX unavailable handlers
powerpc: Don't corrupt transactional state when using FP/VMX in kernel
powerpc: Reclaim two unused thread_info flag bits
powerpc: Fix races with irq_work
Move precessing of MCE queued event out from syscall exit path.
pseries/cpuidle: Remove redundant call to ppc64_runlatch_off() in cpu idle routines
powerpc: Make add_system_ram_resources() __init
powerpc: add SATA_MV to ppc64_defconfig
powerpc/powernv: Increase candidate fw image size
powerpc: Add debug checks to catch invalid cpu-to-node mappings
powerpc: Fix the setup of CPU-to-Node mappings during CPU online
powerpc/iommu: Don't detach device without IOMMU group
powerpc/eeh: Hotplug improvement
powerpc/eeh: Call opal_pci_reinit() on powernv for restoring config space
powerpc/eeh: Add restore_config operation
...
- Remove unnecessary and dangerous use of device_lock
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1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=t9+R
-----END PGP SIGNATURE-----
Merge tag 'vfio-v3.14-rc1' of git://github.com/awilliam/linux-vfio
Pull vfio update from Alex Williamson:
- convert to misc driver to support module auto loading
- remove unnecessary and dangerous use of device_lock
* tag 'vfio-v3.14-rc1' of git://github.com/awilliam/linux-vfio:
vfio-pci: Don't use device_lock around AER interrupt setup
vfio: Convert control interface to misc driver
misc: Reserve minor for VFIO
PCI resets will attempt to take the device_lock for any device to be
reset. This is a problem if that lock is already held, for instance
in the device remove path. It's not sufficient to simply kill the
user process or skip the reset if called after .remove as a race could
result in the same deadlock. Instead, we handle all resets as "best
effort" using the PCI "try" reset interfaces. This prevents the user
from being able to induce a deadlock by triggering a reset.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
device_lock is much too prone to lockups. For instance if we have a
pending .remove then device_lock is already held. If userspace
attempts to modify AER signaling after that point, a deadlock occurs.
eventfd setup/teardown is already protected in vfio with the igate
mutex. AER is not a high performance interrupt, so we can also use
the same mutex to protect signaling versus setup races.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The powerpc iommu uses a hardcoded page size of 4K. This patch changes
the name of the IOMMU_PAGE_* macros to reflect the hardcoded values. A
future patch will use the existing names to support dynamic page
sizes.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This change allows us to support module auto loading using devname
support in userspace tools. With this, /dev/vfio/vfio will always
be present and opening it will cause the vfio module to load. This
should avoid needing to configure the system to statically load
vfio in order to get libvirt to correctly detect support for it.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
These are set of two capability registers, it's pretty much given that
they're registers, so reflect their purpose in the name.
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
In vfio_iommu_type1.c there is a bug in vfio_dma_do_map, when checking
that pages are not already mapped. Since the check is being done in a
for loop nested within the main loop, breaking out of it does not create
the intended behavior. If the underlying IOMMU driver returns a non-NULL
value, this will be ignored and mapping the DMA range will be attempted
anyway, leading to unpredictable behavior.
This interracts badly with the ARM SMMU driver issue fixed in the patch
that was submitted with the title:
"[PATCH 2/2] ARM: SMMU: return NULL on error in arm_smmu_iova_to_phys"
Both fixes are required in order to use the vfio_iommu_type1 driver
with an ARM SMMU.
This patch refactors the function slightly, in order to also make this
kind of bug less likely.
Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The current VFIO_DEVICE_RESET interface only maps to PCI use cases
where we can isolate the reset to the individual PCI function. This
means the device must support FLR (PCIe or AF), PM reset on D3hot->D0
transition, device specific reset, or be a singleton device on a bus
for a secondary bus reset. FLR does not have widespread support,
PM reset is not very reliable, and bus topology is dictated by the
system and device design. We need to provide a means for a user to
induce a bus reset in cases where the existing mechanisms are not
available or not reliable.
This device specific extension to VFIO provides the user with this
ability. Two new ioctls are introduced:
- VFIO_DEVICE_PCI_GET_HOT_RESET_INFO
- VFIO_DEVICE_PCI_HOT_RESET
The first provides the user with information about the extent of
devices affected by a hot reset. This is essentially a list of
devices and the IOMMU groups they belong to. The user may then
initiate a hot reset by calling the second ioctl. We must be
careful that the user has ownership of all the affected devices
found via the first ioctl, so the second ioctl takes a list of file
descriptors for the VFIO groups affected by the reset. Each group
must have IOMMU protection established for the ioctl to succeed.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Having PCIe/PCI-X capability isn't enough to assume that there are
extended capabilities. Both specs define that the first capability
header is all zero if there are no extended capabilities. Testing
for this avoids an erroneous message about hiding capability 0x0 at
offset 0x100.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
eventfd_fget() tests to see whether the file is an eventfd file, which
we then immediately pass to eventfd_ctx_fileget(), which again tests
whether the file is an eventfd file. Simplify slightly by using
fdget() so that we only test that we're looking at an eventfd once.
fget() could also be used, but fdget() makes use of fget_light() for
another slight optimization.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add the default O_CLOEXEC flag for device file descriptors. This is
generally considered a safer option as it allows the user a race free
option to decide whether file descriptors are inherited across exec,
with the default avoiding file descriptor leaks.
Reported-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Macro get_unused_fd() is used to allocate a file descriptor with
default flags. Those default flags (0) can be "unsafe":
O_CLOEXEC must be used by default to not leak file descriptor
across exec().
Instead of macro get_unused_fd(), functions anon_inode_getfd()
or get_unused_fd_flags() should be used with flags given by userspace.
If not possible, flags should be set to O_CLOEXEC to provide userspace
with a default safe behavor.
In a further patch, get_unused_fd() will be removed so that
new code start using anon_inode_getfd() or get_unused_fd_flags()
with correct flags.
This patch replaces calls to get_unused_fd() with equivalent call to
get_unused_fd_flags(0) to preserve current behavor for existing code.
The hard coded flag value (0) should be reviewed on a per-subsystem basis,
and, if possible, set to O_CLOEXEC.
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Link: http://lkml.kernel.org/r/cover.1376327678.git.ydroneaud@opteya.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
VFIO is designed to be used via ioctls on file descriptors
returned by VFIO.
However in some situations support for an external user is required.
The first user is KVM on PPC64 (SPAPR TCE protocol) which is going to
use the existing VFIO groups for exclusive access in real/virtual mode
on a host to avoid passing map/unmap requests to the user space which
would made things pretty slow.
The protocol includes:
1. do normal VFIO init operation:
- opening a new container;
- attaching group(s) to it;
- setting an IOMMU driver for a container.
When IOMMU is set for a container, all groups in it are
considered ready to use by an external user.
2. User space passes a group fd to an external user.
The external user calls vfio_group_get_external_user()
to verify that:
- the group is initialized;
- IOMMU is set for it.
If both checks passed, vfio_group_get_external_user()
increments the container user counter to prevent
the VFIO group from disposal before KVM exits.
3. The external user calls vfio_external_user_iommu_id()
to know an IOMMU ID. PPC64 KVM uses it to link logical bus
number (LIOBN) with IOMMU ID.
4. When the external KVM finishes, it calls
vfio_group_put_external_user() to release the VFIO group.
This call decrements the container user counter.
Everything gets released.
The "vfio: Limit group opens" patch is also required for the consistency.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
If an attempt is made to unbind a device from vfio-pci while that
device is in use, the request is blocked until the device becomes
unused. Unfortunately, that unbind path still grabs the device_lock,
which certain things like __pci_reset_function() also want to take.
This means we need to try to acquire the locks ourselves and use the
pre-locked version, __pci_reset_function_locked().
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Remove debugging WARN_ON if we get a spurious notify for a group that
no longer exists. No reports of anyone hitting this, but it would
likely be a race and not a bug if they did.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
BUS_NOTIFY_DEL_DEVICE triggers IOMMU drivers to remove devices from
their iommu group, but there's really nothing we can do about it at
this point. If the device is in use, then the vfio sub-driver will
block the device_del from completing until it's released. If the
device is not in use or not owned by a vfio sub-driver, then we
really don't care that it's being removed.
The current code can be triggered just by unloading an sr-iov driver
(ex. igb) while the VFs are attached to vfio-pci because it makes an
incorrect assumption about the ordering of driver remove callbacks
vs the DEL_DEVICE notification.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Largely hugepage support for vfio/type1 iommu and surrounding cleanups and fixes.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.13 (GNU/Linux)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=9+Jh
-----END PGP SIGNATURE-----
Merge tag 'vfio-v3.11' of git://github.com/awilliam/linux-vfio
Pull vfio updates from Alex Williamson:
"Largely hugepage support for vfio/type1 iommu and surrounding cleanups
and fixes"
* tag 'vfio-v3.11' of git://github.com/awilliam/linux-vfio:
vfio/type1: Fix leak on error path
vfio: Limit group opens
vfio/type1: Fix missed frees and zero sized removes
vfio: fix documentation
vfio: Provide module option to disable vfio_iommu_type1 hugepage support
vfio: hugepage support for vfio_iommu_type1
vfio: Convert type1 iommu to use rbtree
Pull powerpc updates from Ben Herrenschmidt:
"This is the powerpc changes for the 3.11 merge window. In addition to
the usual bug fixes and small updates, the main highlights are:
- Support for transparent huge pages by Aneesh Kumar for 64-bit
server processors. This allows the use of 16M pages as transparent
huge pages on kernels compiled with a 64K base page size.
- Base VFIO support for KVM on power by Alexey Kardashevskiy
- Wiring up of our nvram to the pstore infrastructure, including
putting compressed oopses in there by Aruna Balakrishnaiah
- Move, rework and improve our "EEH" (basically PCI error handling
and recovery) infrastructure. It is no longer specific to pseries
but is now usable by the new "powernv" platform as well (no
hypervisor) by Gavin Shan.
- I fixed some bugs in our math-emu instruction decoding and made it
usable to emulate some optional FP instructions on processors with
hard FP that lack them (such as fsqrt on Freescale embedded
processors).
- Support for Power8 "Event Based Branch" facility by Michael
Ellerman. This facility allows what is basically "userspace
interrupts" for performance monitor events.
- A bunch of Transactional Memory vs. Signals bug fixes and HW
breakpoint/watchpoint fixes by Michael Neuling.
And more ... I appologize in advance if I've failed to highlight
something that somebody deemed worth it."
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (156 commits)
pstore: Add hsize argument in write_buf call of pstore_ftrace_call
powerpc/fsl: add MPIC timer wakeup support
powerpc/mpic: create mpic subsystem object
powerpc/mpic: add global timer support
powerpc/mpic: add irq_set_wake support
powerpc/85xx: enable coreint for all the 64bit boards
powerpc/8xx: Erroneous double irq_eoi() on CPM IRQ in MPC8xx
powerpc/fsl: Enable CONFIG_E1000E in mpc85xx_smp_defconfig
powerpc/mpic: Add get_version API both for internal and external use
powerpc: Handle both new style and old style reserve maps
powerpc/hw_brk: Fix off by one error when validating DAWR region end
powerpc/pseries: Support compression of oops text via pstore
powerpc/pseries: Re-organise the oops compression code
pstore: Pass header size in the pstore write callback
powerpc/powernv: Fix iommu initialization again
powerpc/pseries: Inform the hypervisor we are using EBB regs
powerpc/perf: Add power8 EBB support
powerpc/perf: Core EBB support for 64-bit book3s
powerpc/perf: Drop MMCRA from thread_struct
powerpc/perf: Don't enable if we have zero events
...
We also don't handle unpinning zero pages as an error on other exits
so we can fix that inconsistency by rolling in the next conditional
return.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio_group_fops_open attempts to limit concurrent sessions by
disallowing opens once group->container is set. This really doesn't
do what we want and allow for inconsistent behavior, for instance a
group can be opened twice, then a container set giving the user two
file descriptors to the group. But then it won't allow more to be
opened. There's not much reason to have the group opened multiple
times since most access is through devices or the container, so
complete what the original code intended and only allow a single
instance.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
With hugepage support we can only properly aligned and sized ranges.
We only guarantee that we can unmap the same ranges mapped and not
arbitrary sub-ranges. This means we might not free anything or might
free more than requested. The vfio unmap interface started storing
the unmapped size to return to userspace to handle this. This patch
fixes a few places where we don't properly handle those cases, moves
a memory allocation to a place where failure is an option and checks
our loops to make sure we don't get into an infinite loop trying to
remove an overlap.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a module option to vfio_iommu_type1 to disable IOMMU hugepage
support. This causes iommu_map to only be called with single page
mappings, disabling the IOMMU driver's ability to use hugepages.
This option can be enabled by loading vfio_iommu_type1 with
disable_hugepages=1 or dynamically through sysfs. If enabled
dynamically, only new mappings are restricted.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We currently send all mappings to the iommu in PAGE_SIZE chunks,
which prevents the iommu from enabling support for larger page sizes.
We still need to pin pages, which means we step through them in
PAGE_SIZE chunks, but we can batch up contiguous physical memory
chunks to allow the iommu the opportunity to use larger pages. The
approach here is a bit different that the one currently used for
legacy KVM device assignment. Rather than looking at the vma page
size and using that as the maximum size to pass to the iommu, we
instead simply look at whether the next page is physically
contiguous. This means we might ask the iommu to map a 4MB region,
while legacy KVM might limit itself to a maximum of 2MB.
Splitting our mapping path also allows us to be smarter about locked
memory because we can more easily unwind if the user attempts to
exceed the limit. Therefore, rather than assuming that a mapping
will result in locked memory, we test each page as it is pinned to
determine whether it locks RAM vs an mmap'd MMIO region. This should
result in better locking granularity and less locked page fudge
factors in userspace.
The unmap path uses the same algorithm as legacy KVM. We don't want
to track the pfn for each mapping ourselves, but we need the pfn in
order to unpin pages. We therefore ask the iommu for the iova to
physical address translation, ask it to unpin a page, and see how many
pages were actually unpinned. iommus supporting large pages will
often return something bigger than a page here, which we know will be
physically contiguous and we can unpin a batch of pfns. iommus not
supporting large mappings won't see an improvement in batching here as
they only unmap a page at a time.
With this change, we also make a clarification to the API for mapping
and unmapping DMA. We can only guarantee unmaps at the same
granularity as used for the original mapping. In other words,
unmapping a subregion of a previous mapping is not guaranteed and may
result in a larger or smaller unmapping than requested. The size
field in the unmapping structure is updated to reflect this.
Previously this was unmodified on mapping, always returning the the
requested unmap size. This is now updated to return the actual unmap
size on success, allowing userspace to appropriately track mappings.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We need to keep track of all the DMA mappings of an iommu container so
that it can be automatically unmapped when the user releases the file
descriptor. We currently do this using a simple list, where we merge
entries with contiguous iovas and virtual addresses. Using a tree for
this is a bit more efficient and allows us to use common code instead
of inventing our own.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The enables VFIO on the pSeries platform, enabling user space
programs to access PCI devices directly.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
VFIO implements platform independent stuff such as
a PCI driver, BAR access (via read/write on a file descriptor
or direct mapping when possible) and IRQ signaling.
The platform dependent part includes IOMMU initialization
and handling. This implements an IOMMU driver for VFIO
which does mapping/unmapping pages for the guest IO and
provides information about DMA window (required by a POWER
guest).
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
devtmpfs_delete_node() calls devnode() callback with mode==NULL but
vfio still tries to write there.
The patch fixes this.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Changes include extension to support PCI AER notification to userspace, byte granularity of PCI config space and access to unarchitected PCI config space, better protection around IOMMU driver accesses, default file mode fix, and a few misc cleanups.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.13 (GNU/Linux)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=F0Cc
-----END PGP SIGNATURE-----
Merge tag 'vfio-for-v3.10' of git://github.com/awilliam/linux-vfio
Pull vfio updates from Alex Williamson:
"Changes include extension to support PCI AER notification to
userspace, byte granularity of PCI config space and access to
unarchitected PCI config space, better protection around IOMMU driver
accesses, default file mode fix, and a few misc cleanups."
* tag 'vfio-for-v3.10' of git://github.com/awilliam/linux-vfio:
vfio: Set container device mode
vfio: Use down_reads to protect iommu disconnects
vfio: Convert container->group_lock to rwsem
PCI/VFIO: use pcie_flags_reg instead of access PCI-E Capabilities Register
vfio-pci: Enable raw access to unassigned config space
vfio-pci: Use byte granularity in config map
vfio: make local function vfio_pci_intx_unmask_handler() static
VFIO-AER: Vfio-pci driver changes for supporting AER
VFIO: Wrapper for getting reference to vfio_device
Minor 0 is the VFIO container device (/dev/vfio/vfio). On it's own
the container does not provide a user with any privileged access. It
only supports API version check and extension check ioctls. Only by
attaching a VFIO group to the container does it gain any access. Set
the mode of the container to allow access.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
If a group or device is released or a container is unset from a group
it can race against file ops on the container. Protect these with
down_reads to allow concurrent users.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reported-by: Michael S. Tsirkin <mst@redhat.com>
All current users are writers, maintaining current mutual exclusion.
This lets us add read users next.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We now cache the MSI/MSI-X capability offsets in the struct pci_dev,
so no need to find the capabilities again.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
PCI_MSIX_FLAGS_BIRMASK is mis-named because the BIR mask is in the
Table Offset register, not the flags ("Message Control" per spec)
register.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Currently, we use pcie_flags_reg to cache PCI-E Capabilities Register,
because PCI-E Capabilities Register bits are almost read-only. This patch
use pcie_caps_reg() instead of another access PCI-E Capabilities Register.
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Devices like be2net hide registers between the gaps in capabilities
and architected regions of PCI config space. Our choices to support
such devices is to either build an ever growing and unmanageable white
list or rely on hardware isolation to protect us. These registers are
really no different than MMIO or I/O port space registers, which we
don't attempt to regulate, so treat PCI config space in the same way.
Reported-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Gavin Shan <shangw@linux.vnet.ibm.com>
The config map previously used a byte per dword to map regions of
config space to capabilities. Modulo a bug where we round the length
of capabilities down instead of up, this theoretically works well and
saves space so long as devices don't try to hide registers in the gaps
between capabilities. Unfortunately they do exactly that so we need
byte granularity on our config space map. Increase the allocation of
the config map and split accesses at capability region boundaries.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Tested-by: Gavin Shan <shangw@linux.vnet.ibm.com>
The VFIO_DEVICE_SET_IRQS ioctl takes a start and count parameter, both
of which are unsigned. We attempt to bounds check these, but fail to
account for the case where start is a very large number, allowing
start + count to wrap back into the valid range. Bounds check both
start and start + count.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio_pci_intx_unmask_handler() was not declared. It should be static.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The vfio drivers call kmalloc or kzalloc, but do not
include <linux/slab.h>, which causes build errors on
ARM.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: kvm@vger.kernel.org
- New VFIO_SET_IRQ ioctl option to pass the eventfd that is signaled when
an error occurs in the vfio_pci_device
- Register pci_error_handler for the vfio_pci driver
- When the device encounters an error, the error handler registered by
the vfio_pci driver gets invoked by the AER infrastructure
- In the error handler, signal the eventfd registered for the device.
- This results in the qemu eventfd handler getting invoked and
appropriate action taken for the guest.
Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
- Added vfio_device_get_from_dev() as wrapper to get
reference to vfio_device from struct device.
- Added vfio_device_data() as a wrapper to get device_data from
vfio_device.
Signed-off-by: Vijay Mohan Pandarathil <vijaymohan.pandarathil@hp.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Convert to the much saner new idr interface.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The CONFIG_EXPERIMENTAL config item has not carried much meaning for a
while now and is almost always enabled by default. As agreed during the
Linux kernel summit, remove it from any "depends on" lines in Kconfigs.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
PCI defines display class VGA regions at I/O port address 0x3b0, 0x3c0
and MMIO address 0xa0000. As these are non-overlapping, we can ignore
the I/O port vs MMIO difference and expose them both in a single
region. We make use of the VGA arbiter around each access to
configure chipset access as necessary.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We give the user access to change the power state of the device but
certain transitions result in an uninitialized state which the user
cannot resolve. To fix this we need to mark the PowerState field of
the PMCSR register read-only and effect the requested change on behalf
of the user. This has the added benefit that pdev->current_state
remains accurate while controlled by the user.
The primary example of this bug is a QEMU guest doing a reboot where
the device it put into D3 on shutdown and becomes unusable on the next
boot because the device did a soft reset on D3->D0 (NoSoftRst-).
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
pcieport does nice things like manage AER and we know it doesn't do
DMA or expose any user accessible devices on the host. It also keeps
the Memory, I/O, and Busmaster bits enabled, which is pretty handy
when trying to use anyting below it. Devices owned by pcieport cannot
be given to users via vfio, but we can tolerate them not being owned
by vfio-pci.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio_dev_present is meant to give us a wait_event callback so that we
can block removing a device from vfio until it becomes unused. The
root of this check depends on being able to get the iommu group from
the device. Unfortunately if the BUS_NOTIFY_DEL_DEVICE notifier has
fired then the device-group reference is no longer searchable and we
fail the lookup.
We don't need to go to such extents for this though. We have a
reference to the device, from which we can acquire a reference to the
group. We can then use the group reference to search for the device
and properly block removal.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We can actually handle MMIO and I/O port from the same access function
since PCI already does abstraction of this. The ROM BAR only requires
a minor difference, so it gets included too. vfio_pci_config_readwrite
gets renamed for consistency.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The read and write functions are nearly identical, combine them
and convert to a switch statement. This also makes it easy to
narrow the scope of when we use the io/mem accessors in case new
regions are added.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
A read from a range hidden from the user (ex. MSI-X vector table)
attempts to fill the user buffer up to the end of the excluded range
instead of up to the requested count. Fix it.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Cc: stable@vger.kernel.org
Devices making use of PM reset are getting incorrectly identified as
not supporting reset because pci_pm_reset() fails unless the device is
in D0 power state. When first attached to vfio_pci devices are
typically in an unknown power state. We can fix this by explicitly
setting the power state or simply calling pci_enable_device() before
attempting a pci_reset_function(). We need to enable the device
anyway, so move this up in our vfio_pci_enable() function, which also
simplifies the error path a bit.
Note that pci_disable_device() does not explicitly set the power
state, so there's no need to re-order vfio_pci_disable().
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The two labels for error recovery in function vfio_pci_init() is out of
order, so fix it.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Comments from dev_driver_string(),
/* dev->driver can change to NULL underneath us because of unbinding,
* so be careful about accessing it.
*/
So use ACCESS_ONCE() to guard access to dev->driver field.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
On error recovery path in function vfio_create_group(), it should
unregister the IOMMU notifier for the new VFIO group. Otherwise it may
cause invalid memory access later when handling bus notifications.
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Move the device reset to the end of our disable path, the device
should already be stopped from pci_disable_device(). This also allows
us to manipulate the save/restore to avoid the save/reset/restore +
save/restore that we had before.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The virq_disabled flag tracks the userspace view of INTx masking
across interrupt mode changes, but we're not consistently applying
this to the interrupt and masking handler notion of the device.
Currently if the user sets DisINTx while in MSI or MSIX mode, then
returns to INTx mode (ex. rebooting a qemu guest), the hardware has
DisINTx+, but the management of INTx thinks it's enabled, making it
impossible to actually clear DisINTx. Fix this by updating the
handler state when INTx is re-enabled.
Cc: stable@vger.kernel.org
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We need to be ready to recieve an interrupt as soon as we call
request_irq, so our eventfd context setting needs to be moved
earlier. Without this, an interrupt from our device or one
sharing the interrupt line can pass a NULL into eventfd_signal
and oops.
Cc: stable@vger.kernel.org
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Our mmap path mistakely relied on vma->vm_pgoff to get set in
remap_pfn_range. After b3b9c293, that path only applies to
copy-on-write mappings. Set it in our own code.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The VM_RESERVED flag was killed off in commit 314e51b985 ("mm: kill
vma flag VM_RESERVED and mm->reserved_vm counter"), and replaced by the
proper semantic flags (eg "don't core-dump" etc). But there was a new
use of VM_RESERVED that got missed by the merge.
Fix the remaining use of VM_RESERVED in the vfio_pci driver, replacing
the VM_RESERVED flag with VM_DONTEXPAND | VM_DONTDUMP.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation,org>
vfoi-pci supports a mechanism like KVM's irqfd for unmasking an
interrupt through an eventfd. There are two ways to shutdown this
interface: 1) close the eventfd, 2) ioctl (such as disabling the
interrupt). Both of these do the release through a workqueue,
which can result in a segfault if two jobs get queued for the same
virqfd.
Fix this by protecting the pointer to these virqfds by a spinlock.
The vfio pci device will therefore no longer have a reference to it
once the release job is queued under lock. On the ioctl side, we
still flush the workqueue to ensure that any outstanding releases
are completed.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
It's not critical (anymore) since another thread closing the file will block
on ->device_lock before it gets to dropping the final reference, but it's
definitely cleaner that way...
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
we really need to make sure that dropping the last reference happens
under the group->device_lock; otherwise a loop (under device_lock)
might find vfio_device instance that is being freed right now, has
already dropped the last reference and waits on device_lock to exclude
the sucker from the list.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Add PCI device support for VFIO. PCI devices expose regions
for accessing config space, I/O port space, and MMIO areas
of the device. PCI config access is virtualized in the kernel,
allowing us to ensure the integrity of the system, by preventing
various accesses while reducing duplicate support across various
userspace drivers. I/O port supports read/write access while
MMIO also supports mmap of sufficiently sized regions. Support
for INTx, MSI, and MSI-X interrupts are provided using eventfds to
userspace.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This VFIO IOMMU backend is designed primarily for AMD-Vi and Intel
VT-d hardware, but is potentially usable by anything supporting
similar mapping functionality. We arbitrarily call this a Type1
backend for lack of a better name. This backend has no IOVA
or host memory mapping restrictions for the user and is optimized
for relatively static mappings. Mapped areas are pinned into system
memory.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
VFIO is a secure user level driver for use with both virtual machines
and user level drivers. VFIO makes use of IOMMU groups to ensure the
isolation of devices in use, allowing unprivileged user access. It's
intended that VFIO will replace KVM device assignment and UIO drivers
(in cases where the target platform includes a sufficiently capable
IOMMU).
New in this version of VFIO is support for IOMMU groups managed
through the IOMMU core as well as a rework of the API, removing the
group merge interface. We now go back to a model more similar to
original VFIO with UIOMMU support where the file descriptor obtained
from /dev/vfio/vfio allows access to the IOMMU, but only after a
group is added, avoiding the previous privilege issues with this type
of model. IOMMU support is also now fully modular as IOMMUs have
vastly different interface requirements on different platforms. VFIO
users are able to query and initialize the IOMMU model of their
choice.
Please see the follow-on Documentation commit for further description
and usage example.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>