This results in less kconfig wordage and a simpler understanding of the
required "depends on" to create the menu structure.
The next patch increases the nesting level a lot so this is a nice
preparatory simplification.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-13-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
If VFIO_VIRQFD is required then turn on eventfd automatically.
The majority of kconfig users of the EVENTFD use select not depends on.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-12-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
VFIO_NOIOMMU is supposed to be an element in the VFIO menu, not start
a new menu. Correct this copy-paste mistake.
Fixes: 03a76b60f8 ("vfio: Include No-IOMMU mode")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/0-v1-3f0b685c3679+478-vfio_menuconfig_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
VFIO_IOMMU_TYPE1 does not compile with !MMU:
../drivers/vfio/vfio_iommu_type1.c: In function 'follow_fault_pfn':
../drivers/vfio/vfio_iommu_type1.c:536:22: error: implicit declaration of function 'pte_write'; did you mean 'vfs_write'? [-Werror=implicit-function-declaration]
So require it.
Suggested-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <0-v1-02cb5500df6e+78-vfio_no_mmu_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
As IOMMU_API is a kconfig without a description (eg does not show in the
menu) the correct operator is select not 'depends on'. Using 'depends on'
for this kind of symbol means VFIO is not selectable unless some other
random kconfig has already enabled IOMMU_API for it.
Fixes: cba3345cc4 ("vfio: VFIO core")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <1-v1-df057e0f92c3+91-vfio_arm_compile_test_jgg@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
DPAA2 (Data Path Acceleration Architecture) consists in
mechanisms for processing Ethernet packets, queue management,
accelerators, etc.
The Management Complex (mc) is a hardware entity that manages the DPAA2
hardware resources. It provides an object-based abstraction for software
drivers to use the DPAA2 hardware. The MC mediates operations such as
create, discover, destroy of DPAA2 objects.
The MC provides memory-mapped I/O command interfaces (MC portals) which
DPAA2 software drivers use to operate on DPAA2 objects.
A DPRC is a container object that holds other types of DPAA2 objects.
Each object in the DPRC is a Linux device and bound to a driver.
The MC-bus driver is a platform driver (different from PCI or platform
bus). The DPRC driver does runtime management of a bus instance. It
performs the initial scan of the DPRC and handles changes in the DPRC
configuration (adding/removing objects).
All objects inside a container share the same hardware isolation
context, meaning that only an entire DPRC can be assigned to
a virtual machine.
When a container is assigned to a virtual machine, all the objects
within that container are assigned to that virtual machine.
The DPRC container assigned to the virtual machine is not allowed
to change contents (add/remove objects) by the guest. The restriction
is set by the host and enforced by the mc hardware.
The DPAA2 objects can be directly assigned to the guest. However
the MC portals (the memory mapped command interface to the MC) need
to be emulated because there are commands that configure the
interrupts and the isolation IDs which are virtual in the guest.
Example:
echo vfio-fsl-mc > /sys/bus/fsl-mc/devices/dprc.2/driver_override
echo dprc.2 > /sys/bus/fsl-mc/drivers/vfio-fsl-mc/bind
The dprc.2 is bound to the VFIO driver and all the objects within
dprc.2 are going to be bound to the VFIO driver.
This patch adds the infrastructure for VFIO support for fsl-mc
devices. Subsequent patches will add support for binding and secure
assigning these devices using VFIO.
More details about the DPAA2 objects can be found here:
Documentation/networking/device_drivers/freescale/dpaa2/overview.rst
Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com>
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There are lots of documents under Documentation/*.txt and a few other
orphan documents elsehwere that belong to the driver-API book.
Move them to their right place.
Reviewed-by: Cornelia Huck <cohuck@redhat.com> # vfio-related parts
Acked-by: Logan Gunthorpe <logang@deltatee.com> # switchtec
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make the anon_inodes facility unconditional so that it can be used by core
VFS code and pidfd code.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[christian@brauner.io: adapt commit message to mention pidfds]
Signed-off-by: Christian Brauner <christian@brauner.io>
Currently the type-1 IOMMU instantiation depends on "ARM_SMMU ||
ARM_SMMU_V3", while it applies to other ARM/ARM64 platforms with an
IOMMU (e.g. Renesas VMSA-compatible IPMMUs).
Instead of extending the list of IOMMU types on ARM platforms, replace
the list by "ARM || ARM64", like other architectures do. The feature is
still restricted to ARM/ARM64 platforms with an IOMMU by the dependency
on IOMMU_API.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently the kconfig logic for VFIO_IOMMU_SPAPR_TCE and VFIO_SPAPR_EEH
is broken when SPAPR_TCE_IOMMU=n. Leading to:
warning: (VFIO) selects VFIO_IOMMU_SPAPR_TCE which has unmet direct dependencies (VFIO && SPAPR_TCE_IOMMU)
warning: (VFIO) selects VFIO_IOMMU_SPAPR_TCE which has unmet direct dependencies (VFIO && SPAPR_TCE_IOMMU)
drivers/vfio/vfio_iommu_spapr_tce.c:113:8: error: implicit declaration of function 'mm_iommu_find'
This stems from the fact that VFIO selects VFIO_IOMMU_SPAPR_TCE, and
although it has an if clause, the condition is not correct.
We could fix it by doing select VFIO_IOMMU_SPAPR_TCE if SPAPR_TCE_IOMMU,
but the cleaner fix is to drop the selects and tie VFIO_IOMMU_SPAPR_TCE
to the value of VFIO, and express the dependencies in only once place.
Do the same for VFIO_SPAPR_EEH.
The end result is that the values of VFIO_IOMMU_SPAPR_TCE and
VFIO_SPAPR_EEH follow the value of VFIO, except when SPAPR_TCE_IOMMU=n
and/or EEH=n. Which is exactly what we want to happen.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Design for Mediated Device Driver:
Main purpose of this driver is to provide a common interface for mediated
device management that can be used by different drivers of different
devices.
This module provides a generic interface to create the device, add it to
mediated bus, add device to IOMMU group and then add it to vfio group.
Below is the high Level block diagram, with Nvidia, Intel and IBM devices
as example, since these are the devices which are going to actively use
this module as of now.
+---------------+
| |
| +-----------+ | mdev_register_driver() +--------------+
| | | +<------------------------+ __init() |
| | mdev | | | |
| | bus | +------------------------>+ |<-> VFIO user
| | driver | | probe()/remove() | vfio_mdev.ko | APIs
| | | | | |
| +-----------+ | +--------------+
| |
| MDEV CORE |
| MODULE |
| mdev.ko |
| +-----------+ | mdev_register_device() +--------------+
| | | +<------------------------+ |
| | | | | nvidia.ko |<-> physical
| | | +------------------------>+ | device
| | | | callback +--------------+
| | Physical | |
| | device | | mdev_register_device() +--------------+
| | interface | |<------------------------+ |
| | | | | i915.ko |<-> physical
| | | +------------------------>+ | device
| | | | callback +--------------+
| | | |
| | | | mdev_register_device() +--------------+
| | | +<------------------------+ |
| | | | | ccw_device.ko|<-> physical
| | | +------------------------>+ | device
| | | | callback +--------------+
| +-----------+ |
+---------------+
Core driver provides two types of registration interfaces:
1. Registration interface for mediated bus driver:
/**
* struct mdev_driver - Mediated device's driver
* @name: driver name
* @probe: called when new device created
* @remove:called when device removed
* @driver:device driver structure
*
**/
struct mdev_driver {
const char *name;
int (*probe) (struct device *dev);
void (*remove) (struct device *dev);
struct device_driver driver;
};
Mediated bus driver for mdev device should use this interface to register
and unregister with core driver respectively:
int mdev_register_driver(struct mdev_driver *drv, struct module *owner);
void mdev_unregister_driver(struct mdev_driver *drv);
Mediated bus driver is responsible to add/delete mediated devices to/from
VFIO group when devices are bound and unbound to the driver.
2. Physical device driver interface
This interface provides vendor driver the set APIs to manage physical
device related work in its driver. APIs are :
* dev_attr_groups: attributes of the parent device.
* mdev_attr_groups: attributes of the mediated device.
* supported_type_groups: attributes to define supported type. This is
mandatory field.
* create: to allocate basic resources in vendor driver for a mediated
device. This is mandatory to be provided by vendor driver.
* remove: to free resources in vendor driver when mediated device is
destroyed. This is mandatory to be provided by vendor driver.
* open: open callback of mediated device
* release: release callback of mediated device
* read : read emulation callback.
* write: write emulation callback.
* ioctl: ioctl callback.
* mmap: mmap emulation callback.
Drivers should use these interfaces to register and unregister device to
mdev core driver respectively:
extern int mdev_register_device(struct device *dev,
const struct parent_ops *ops);
extern void mdev_unregister_device(struct device *dev);
There are no locks to serialize above callbacks in mdev driver and
vfio_mdev driver. If required, vendor driver can have locks to serialize
above APIs in their driver.
Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Reviewed-by: Jike Song <jike.song@intel.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@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>
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>
- 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)
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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
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 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>
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>
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>
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>
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>
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>
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>
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>
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>
Jason Gunthorpe