Commit Graph

57 Commits

Author SHA1 Message Date
Kevin Tian e19c0b65fe vfio: Rename vfio_device_put() and vfio_device_try_get()
ANBZ: #10925

commit 4a725b8de4 upstream.

With the addition of vfio_put_device() now the names become confusing.

vfio_put_device() is clear from object life cycle p.o.v given kref.

vfio_device_put()/vfio_device_try_get() are helpers for tracking
users on a registered device.

Now rename them:

 - vfio_device_put() -> vfio_device_put_registration()
 - vfio_device_try_get() -> vfio_device_try_get_registration()

Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link:
https://lore.kernel.org/r/20220921104401.38898-15-kevin.tian@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/5474
2025-07-02 03:31:13 +00:00
Alex Williamson 8d7b7a8185 vfio: Introduce interface to flush virqfd inject workqueue
ANBZ: #12616

commit d6f77b5e47855ce4c0a8fbb7b6441d1f9c4db6f3 stable.

[ Upstream commit b620ecbd17 ]

In order to synchronize changes that can affect the thread callback,
introduce an interface to force a flush of the inject workqueue.  The
irqfd pointer is only valid under spinlock, but the workqueue cannot
be flushed under spinlock.  Therefore the flush work for the irqfd is
queued under spinlock.  The vfio_irqfd_cleanup_wq workqueue is re-used
for queuing this work such that flushing the workqueue is also ordered
relative to shutdown.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20240308230557.805580-4-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fixes: CVE-2024-26812
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/4389
2025-03-26 08:41:52 +00:00
Kevin Tian b8aa9d846b vfio: Add helpers for unifying vfio_device life cycle
ANBZ: #10925

commit cb9ff3f3b8 upstream.

The idea is to let vfio core manage the vfio_device life cycle instead
of duplicating the logic cross drivers. This is also a preparatory
step for adding struct device into vfio_device.

New pair of helpers together with a kref in vfio_device:

 - vfio_alloc_device()
 - vfio_put_device()

Drivers can register @init/@release callbacks to manage any private
state wrapping the vfio_device.

However vfio-ccw doesn't fit this model due to a life cycle mess
that its private structure mixes both parent and mdev info hence must
be allocated/freed outside of the life cycle of vfio device.

Per prior discussions this won't be fixed in short term by IBM folks.

Instead of waiting for those modifications introduce another helper
vfio_init_device() so ccw can call it to initialize a pre-allocated
vfio_device.

Further implication of the ccw trick is that vfio_device cannot be
freed uniformly in vfio core. Instead, require *EVERY* driver to
implement @release and free vfio_device inside. Then ccw can choose
to delay the free at its own discretion.

Another trick down the road is that kvzalloc() is used to accommodate
the need of gvt which uses vzalloc() while all others use kzalloc().
So drivers should call a helper vfio_free_device() to free the
vfio_device instead of assuming that kfree() or vfree() is appliable.

Later once the ccw mess is fixed we can remove those tricks and
fully handle structure alloc/free in vfio core.

Existing vfio_{un}init_group_dev() will be deprecated after all
existing usages are converted to the new model.

Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Co-developed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20220921104401.38898-2-kevin.tian@intel.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3855
2024-11-12 13:28:27 +00:00
Yishai Hadas 1ec4a0e132 vfio: Add an option to get migration data size
ANBZ: #10925

commit 4e016f9695 upstream.

Add an option to get migration data size by introducing a new migration
feature named VFIO_DEVICE_FEATURE_MIG_DATA_SIZE.

Upon VFIO_DEVICE_FEATURE_GET the estimated data length that will be
required to complete STOP_COPY is returned.

This option may better enable user space to consider before moving to
STOP_COPY whether it can meet the downtime SLA based on the returned
data.

The patch also includes the implementation for mlx5 and hisi for this
new option to make it feature complete for the existing drivers in this
area.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Longfang Liu <liulongfang@huawei.com>
Link: https://lore.kernel.org/r/20221106174630.25909-2-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3855
2024-11-12 13:28:27 +00:00
Yishai Hadas 65098e4fa3 vfio: Introduce the DMA logging feature support
ANBZ: #10925

commit 80c4b92a2d upstream.

Introduce the DMA logging feature support in the vfio core layer.

It includes the processing of the device start/stop/report DMA logging
UAPIs and calling the relevant driver 'op' to do the work.

Specifically,
Upon start, the core translates the given input ranges into an interval
tree, checks for unexpected overlapping, non aligned ranges and then
pass the translated input to the driver for start tracking the given
ranges.

Upon report, the core translates the given input user space bitmap and
page size into an IOVA kernel bitmap iterator. Then it iterates it and
call the driver to set the corresponding bits for the dirtied pages in a
specific IOVA range.

Upon stop, the driver is called to stop the previous started tracking.

The next patches from the series will introduce the mlx5 driver
implementation for the logging ops.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20220908183448.195262-6-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3855
2024-11-12 13:28:27 +00:00
Yishai Hadas 637abaa571 vfio: Split migration ops from main device ops
ANBZ: #10925

commit 6e97eba8ad upstream.

vfio core checks whether the driver sets some migration op (e.g.
set_state/get_state) and accordingly calls its op.

However, currently mlx5 driver sets the above ops without regards to its
migration caps.

This might lead to unexpected usage/Oops if user space may call to the
above ops even if the driver doesn't support migration. As for example,
the migration state_mutex is not initialized in that case.

The cleanest way to manage that seems to split the migration ops from
the main device ops, this will let the driver setting them separately
from the main ops when it's applicable.

As part of that, validate ops construction on registration and include a
check for VFIO_MIGRATION_STOP_COPY since the uAPI claims it must be set
in migration_flags.

HISI driver was changed as well to match this scheme.

This scheme may enable down the road to come with some extra group of
ops (e.g. DMA log) that can be set without regards to the other options
based on driver caps.

Fixes: 6fadb02126 ("vfio/mlx5: Implement vfio_pci driver for mlx5 devices")
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20220628155910.171454-3-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3855
2024-11-12 13:28:27 +00:00
Jason Gunthorpe eed66fc051 vfio: Extend the device migration protocol with RUNNING_P2P
ANBZ: #10925

commit 8cb3d83b95 upstream.

The RUNNING_P2P state is designed to support multiple devices in the same
VM that are doing P2P transactions between themselves. When in RUNNING_P2P
the device must be able to accept incoming P2P transactions but should not
generate outgoing P2P transactions.

As an optional extension to the mandatory states it is defined as
in between STOP and RUNNING:
   STOP -> RUNNING_P2P -> RUNNING -> RUNNING_P2P -> STOP

For drivers that are unable to support RUNNING_P2P the core code
silently merges RUNNING_P2P and RUNNING together. Unless driver support
is present, the new state cannot be used in SET_STATE.
Drivers that support this will be required to implement 4 FSM arcs
beyond the basic FSM. 2 of the basic FSM arcs become combination
transitions.

Compared to the v1 clarification, NDMA is redefined into FSM states and is
described in terms of the desired P2P quiescent behavior, noting that
halting all DMA is an acceptable implementation.

Link: https://lore.kernel.org/all/20220224142024.147653-11-yishaih@nvidia.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3855
2024-11-12 13:28:27 +00:00
Jason Gunthorpe 02d6235f45 vfio: Define device migration protocol v2
ANBZ: #10925

commit 115dcec65f upstream.

Replace the existing region based migration protocol with an ioctl based
protocol. The two protocols have the same general semantic behaviors, but
the way the data is transported is changed.

This is the STOP_COPY portion of the new protocol, it defines the 5 states
for basic stop and copy migration and the protocol to move the migration
data in/out of the kernel.

Compared to the clarification of the v1 protocol Alex proposed:

https://lore.kernel.org/r/163909282574.728533.7460416142511440919.stgit@omen

This has a few deliberate functional differences:

 - ERROR arcs allow the device function to remain unchanged.

 - The protocol is not required to return to the original state on
   transition failure. Instead userspace can execute an unwind back to
   the original state, reset, or do something else without needing kernel
   support. This simplifies the kernel design and should userspace choose
   a policy like always reset, avoids doing useless work in the kernel
   on error handling paths.

 - PRE_COPY is made optional, userspace must discover it before using it.
   This reflects the fact that the majority of drivers we are aware of
   right now will not implement PRE_COPY.

 - segmentation is not part of the data stream protocol, the receiver
   does not have to reproduce the framing boundaries.

The hybrid FSM for the device_state is described as a Mealy machine by
documenting each of the arcs the driver is required to implement. Defining
the remaining set of old/new device_state transitions as 'combination
transitions' which are naturally defined as taking multiple FSM arcs along
the shortest path within the FSM's digraph allows a complete matrix of
transitions.

A new VFIO_DEVICE_FEATURE of VFIO_DEVICE_FEATURE_MIG_DEVICE_STATE is
defined to replace writing to the device_state field in the region. This
allows returning a brand new FD whenever the requested transition opens
a data transfer session.

The VFIO core code implements the new feature and provides a helper
function to the driver. Using the helper the driver only has to
implement 6 of the FSM arcs and the other combination transitions are
elaborated consistently from those arcs.

A new VFIO_DEVICE_FEATURE of VFIO_DEVICE_FEATURE_MIGRATION is defined to
report the capability for migration and indicate which set of states and
arcs are supported by the device. The FSM provides a lot of flexibility to
make backwards compatible extensions but the VFIO_DEVICE_FEATURE also
allows for future breaking extensions for scenarios that cannot support
even the basic STOP_COPY requirements.

The VFIO_DEVICE_FEATURE_MIG_DEVICE_STATE with the GET option (i.e.
VFIO_DEVICE_FEATURE_GET) can be used to read the current migration state
of the VFIO device.

Data transfer sessions are now carried over a file descriptor, instead of
the region. The FD functions for the lifetime of the data transfer
session. read() and write() transfer the data with normal Linux stream FD
semantics. This design allows future expansion to support poll(),
io_uring, and other performance optimizations.

The complicated mmap mode for data transfer is discarded as current qemu
doesn't take meaningful advantage of it, and the new qemu implementation
avoids substantially all the performance penalty of using a read() on the
region.

Link: https://lore.kernel.org/all/20220224142024.147653-10-yishaih@nvidia.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
[Fixes conflictes]
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3855
2024-11-12 13:28:27 +00:00
Jason Gunthorpe b6d39d5a7d vfio: Have the core code decode the VFIO_DEVICE_FEATURE ioctl
ANBZ: #10925

commit 445ad495f0 upstream.

Invoke a new device op 'device_feature' to handle just the data array
portion of the command. This lifts the ioctl validation to the core code
and makes it simpler for either the core code, or layered drivers, to
implement their own feature values.

Provide vfio_check_feature() to consolidate checking the flags/etc against
what the driver supports.

Link: https://lore.kernel.org/all/20220224142024.147653-9-yishaih@nvidia.com
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3855
2024-11-12 13:28:27 +00:00
Jason Gunthorpe 73bebf1e8a vfio: Remove struct vfio_device_ops open/release
ANBZ: #10925

commit eb24c1007e upstream.

Nothing uses this anymore, delete it.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/14-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3855
2024-11-12 13:28:27 +00:00
Qinyun Tan 78928e80bf Revert "vfio: iommu driver notify callback"
ANBZ: #9152

commit e592296cd6 upstream.

Revert this dead code:
  commit ec5e329 ("vfio: iommu driver notify callback")

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1675184289-267876-8-git-send-email-steven.sistare@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
[Fixes conflicts]
Signed-off-by: Qinyun Tan <qinyuntan@linux.alibaba.com>
Reviewed-by: Guanghui Feng <guanghuifeng@linux.alibaba.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
Link: https://gitee.com/anolis/cloud-kernel/pulls/3258
2024-06-06 05:53:15 +00:00
Jason Gunthorpe a71cd6c2ab vfio: Provide better generic support for open/release vfio_device_ops
ANBZ: #1087

commit 2fd585f4ed upstream.

Currently the driver ops have an open/release pair that is called once
each time a device FD is opened or closed. Add an additional set of
open/close_device() ops which are called when the device FD is opened for
the first time and closed for the last time.

An analysis shows that all of the drivers require this semantic. Some are
open coding it as part of their reflck implementation, and some are just
buggy and miss it completely.

To retain the current semantics PCI and FSL depend on, introduce the idea
of a "device set" which is a grouping of vfio_device's that share the same
lock around opening.

The device set is established by providing a 'set_id' pointer. All
vfio_device's that provide the same pointer will be joined to the same
singleton memory and lock across the whole set. This effectively replaces
the oddly named reflck.

After conversion the set_id will be sourced from:
 - A struct device from a fsl_mc_device (fsl)
 - A struct pci_slot (pci)
 - A struct pci_bus (pci)
 - The struct vfio_device (everything)

The design ensures that the above pointers are live as long as the
vfio_device is registered, so they form reliable unique keys to group
vfio_devices into sets.

This implementation uses xarray instead of searching through the driver
core structures, which simplifies the somewhat tricky locking in this
area.

Following patches convert all the drivers.

Intel-SIG: commit 2fd585f4ed vfio: Provide better generic support for open/release
vfio_device_ops.
SIOV VDCM feature backporting.

Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/4-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
[ Fengqian Gao: amend commit log ]
Signed-off-by: Fengqian Gao <fengqian.gao@intel.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
2022-08-02 16:29:09 +08:00
Max Gurtovoy 90fdd417cc vfio: Introduce a vfio_uninit_group_dev() API call
ANBZ: #1087

commit ae03c3771b upstream.

This pairs with vfio_init_group_dev() and allows undoing any state that is
stored in the vfio_device unrelated to registration. Add appropriately
placed calls to all the drivers.

The following patch will use this to add pre-registration state for the
device set.

Intel-SIG: commit ae03c3771b vfio: Introduce a vfio_uninit_group_dev() API call.
SIOV VDCM feature backporting.

Deviation from upstream:
SKip the conflict in sample file:
        samples/vfio-mdev/mbochs.c
        samples/vfio-mdev/mdpy.c
        samples/vfio-mdev/mtty.c
	samples/vfio-mdev/mdpy.c

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
[ Fengqian Gao: amend commit log ]
Signed-off-by: Fengqian Gao <fengqian.gao@intel.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
2022-08-02 16:29:08 +08:00
Jason Gunthorpe 6d2698d96a vfio: Remove device_data from the vfio bus driver API
ANBZ: #1087

commit 1e04ec1420 upstream.

There are no longer any users, so it can go away. Everything is using
container_of now.

Intel-SIG: commit 1e04ec1420 vfio: Remove device_data from the vfio bus driver API.
SIOV VDCM feature backporting.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <14-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
[ Fengqian Gao: amend commit log ]
Signed-off-by: Fengqian Gao <fengqian.gao@intel.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
2022-08-02 16:28:44 +08:00
Jason Gunthorpe 6bc44d5439 vfio: Make vfio_device_ops pass a 'struct vfio_device *' instead of 'void *'
ANBZ: #1087

commit 6df62c5b05 upstream.

This is the standard kernel pattern, the ops associated with a struct get
the struct pointer in for typesafety. The expected design is to use
container_of to cleanly go from the subsystem level type to the driver
level type without having any type erasure in a void *.

Intel-SIG: commit 6df62c5b05 vfio: Make vfio_device_ops pass a
'struct vfio_device *' instead of 'void *'.
SIOV VDCM feature backporting.

Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <12-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
[ Fengqian Gao: amend commit log ]
Signed-off-by: Fengqian Gao <fengqian.gao@intel.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
2022-08-02 16:28:42 +08:00
Jason Gunthorpe 3849574adb vfio/mdev: Use vfio_init/register/unregister_group_dev
ANBZ: #1087

commit 1ae1b20f6f upstream.

mdev gets little benefit because it doesn't actually do anything, however
it is the last user, so move the vfio_init/register/unregister_group_dev()
code here for now.

Intel-SIG: commit 1ae1b20f6f vfio/mdev: Use vfio_init/register/unregister_group_dev.
SIOV VDCM feature backporting.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <10-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
[ Fengqian Gao: amend commit log ]
Signed-off-by: Fengqian Gao <fengqian.gao@intel.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
2022-08-02 16:28:40 +08:00
Jason Gunthorpe 52c040cfed vfio: Split creation of a vfio_device into init and register ops
ANBZ: #1087

commit 0bfc6a4ea6 upstream.

This makes the struct vfio_device part of the public interface so it
can be used with container_of and so forth, as is typical for a Linux
subystem.

This is the first step to bring some type-safety to the vfio interface by
allowing the replacement of 'void *' and 'struct device *' inputs with a
simple and clear 'struct vfio_device *'

For now the self-allocating vfio_add_group_dev() interface is kept so each
user can be updated as a separate patch.

The expected usage pattern is

  driver core probe() function:
     my_device = kzalloc(sizeof(*mydevice));
     vfio_init_group_dev(&my_device->vdev, dev, ops, mydevice);
     /* other driver specific prep */
     vfio_register_group_dev(&my_device->vdev);
     dev_set_drvdata(dev, my_device);

  driver core remove() function:
     my_device = dev_get_drvdata(dev);
     vfio_unregister_group_dev(&my_device->vdev);
     /* other driver specific tear down */
     kfree(my_device);

Allowing the driver to be able to use the drvdata and vfio_device to go
to/from its own data.

The pattern also makes it clear that vfio_register_group_dev() must be
last in the sequence, as once it is called the core code can immediately
start calling ops. The init/register gap is provided to allow for the
driver to do setup before ops can be called and thus avoid races.

Intel-SIG: commit 0bfc6a4ea6 vfio: Split creation of a vfio_device
into init and register ops.
SIOV VDCM feature backporting.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Message-Id: <3-v3-225de1400dfc+4e074-vfio1_jgg@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
[ Fengqian Gao: amend commit log ]
Signed-off-by: Fengqian Gao <fengqian.gao@intel.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
2022-08-02 16:28:35 +08:00
Steve Sistare 5556a8bc1c vfio: iommu driver notify callback
ANBZ: #1087

commit ec5e32940c upstream.

Define a vfio_iommu_driver_ops notify callback, for sending events to
the driver.  Drivers are not required to provide the callback, and
may ignore any events.  The handling of events is driver specific.

Define the CONTAINER_CLOSE event, called when the container's file
descriptor is closed.  This event signifies that no further state changes
will occur via container ioctl's.

Intel-SIG: commit ec5e32940c vfio: iommu driver notify callback.
SIOV VDCM feature backporting.

Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
[ Fengqian Gao: amend commit log ]
Signed-off-by: Fengqian Gao <fengqian.gao@intel.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
2022-08-02 16:28:32 +08:00
Lu Baolu 23a3e3710e vfio/type1: Add vfio_group_iommu_domain()
ANBZ: #836

commit bdfae1c9a9 upstream.

Add the API for getting the domain from a vfio group. This could be used
by the physical device drivers which rely on the vfio/mdev framework for
mediated device user level access. The typical use case like below:

	unsigned int pasid;
	struct vfio_group *vfio_group;
	struct iommu_domain *iommu_domain;
	struct device *dev = mdev_dev(mdev);
	struct device *iommu_device = mdev_get_iommu_device(dev);

	if (!iommu_device ||
	    !iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX))
		return -EINVAL;

	vfio_group = vfio_group_get_external_user_from_dev(dev);
	if (IS_ERR_OR_NULL(vfio_group))
		return -EFAULT;

	iommu_domain = vfio_group_iommu_domain(vfio_group);
	if (IS_ERR_OR_NULL(iommu_domain)) {
		vfio_group_put_external_user(vfio_group);
		return -EFAULT;
	}

	pasid = iommu_aux_get_pasid(iommu_domain, iommu_device);
	if (pasid < 0) {
		vfio_group_put_external_user(vfio_group);
		return -EFAULT;
	}

	/* Program device context with pasid value. */
	...

Intel-SIG: commit bdfae1c9a9 vfio/type1: Add vfio_group_iommu_domain().
Necessary interface to support SIOV.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
[ Yi Sun: amend commit log ]
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Reviewed-by: Artie Ding <artie.ding@linux.alibaba.com>
2022-08-01 12:26:02 +00:00
Kirti Wankhede 95fc87b441 vfio: Selective dirty page tracking if IOMMU backed device pins pages
Added a check such that only singleton IOMMU groups can pin pages.
>From the point when vendor driver pins any pages, consider IOMMU group
dirty page scope to be limited to pinned pages.

To optimize to avoid walking list often, added flag
pinned_page_dirty_scope to indicate if all of the vfio_groups for each
vfio_domain in the domain_list dirty page scope is limited to pinned
pages. This flag is updated on first pinned pages request for that IOMMU
group and on attaching/detaching group.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Neo Jia <cjia@nvidia.com>
Reviewed-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-05-28 15:53:29 -06:00
Alex Williamson 48219795e7 Merge branches 'v5.7/vfio/alex-sriov-v3' and 'v5.7/vfio/yan-dma-rw-v4' into v5.7/vfio/next 2020-03-24 09:32:41 -06:00
Alex Williamson 5f3874c2a2 vfio: Include optional device match in vfio_device_ops callbacks
Allow bus drivers to provide their own callback to match a device to
the user provided string.

Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24 09:28:25 -06:00
Yan Zhao 40280cf7e8 vfio: avoid inefficient operations on VFIO group in vfio_pin/unpin_pages
vfio_group_pin_pages() and vfio_group_unpin_pages() are introduced to
avoid inefficient search/check/ref/deref opertions associated with VFIO
group as those in each calling into vfio_pin_pages() and
vfio_unpin_pages().

VFIO group is taken as arg directly. The callers combine
search/check/ref/deref operations associated with VFIO group by calling
vfio_group_get_external_user()/vfio_group_get_external_user_from_dev()
beforehand, and vfio_group_put_external_user() afterwards.

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24 09:27:57 -06:00
Yan Zhao 8d46c0cca5 vfio: introduce vfio_dma_rw to read/write a range of IOVAs
vfio_dma_rw will read/write a range of user space memory pointed to by
IOVA into/from a kernel buffer without enforcing pinning the user space
memory.

TODO: mark the IOVAs to user space memory dirty if they are written in
vfio_dma_rw().

Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24 09:27:57 -06:00
Yan Zhao c0560f51cf vfio: allow external user to get vfio group from device
external user calls vfio_group_get_external_user_from_dev() with a device
pointer to get the VFIO group associated with this device.
The VFIO group is checked to be vialbe and have IOMMU set. Then
container user counter is increased and VFIO group reference is hold
to prevent the VFIO group from disposal before external user exits.

when the external user finishes using of the VFIO group, it calls
vfio_group_put_external_user() to dereference the VFIO group and the
container user counter.

Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-03-24 09:27:56 -06:00
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Alex Williamson dda01f787d vfio: Simplify capability helper
The vfio_info_add_capability() helper requires the caller to pass a
capability ID, which it then uses to fill in header fields, assuming
hard coded versions.  This makes for an awkward and rigid interface.
The only thing we want this helper to do is allocate sufficient
space in the caps buffer and chain this capability into the list.
Reduce it to that simple task.

Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-12-20 09:53:54 -07:00
Murilo Opsfelder Araujo bb67b496c3 include/linux/vfio.h: Guard powerpc-specific functions with CONFIG_VFIO_SPAPR_EEH
When CONFIG_EEH=y and CONFIG_VFIO_SPAPR_EEH=n, build fails with the
following:

    drivers/vfio/pci/vfio_pci.o: In function `.vfio_pci_release':
    vfio_pci.c:(.text+0xa98): undefined reference to `.vfio_spapr_pci_eeh_release'
    drivers/vfio/pci/vfio_pci.o: In function `.vfio_pci_open':
    vfio_pci.c:(.text+0x1420): undefined reference to `.vfio_spapr_pci_eeh_open'

In this case, vfio_pci.c should use the empty definitions of
vfio_spapr_pci_eeh_open and vfio_spapr_pci_eeh_release functions.

This patch fixes it by guarding these function definitions with
CONFIG_VFIO_SPAPR_EEH, the symbol that controls whether vfio_spapr_eeh.c is
built, which is where the non-empty versions of these functions are. We need to
make use of IS_ENABLED() macro because CONFIG_VFIO_SPAPR_EEH is a tristate
option.

This issue was found during a randconfig build. Logs are here:

    http://kisskb.ellerman.id.au/kisskb/buildresult/12982362/

Signed-off-by: Murilo Opsfelder Araujo <mopsfelder@gmail.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2017-07-26 13:30:23 -06:00
Linus Torvalds 8c6f5e7359 VFIO updates for v4.13-rc1
- Include Intel XXV710 in INTx workaround (Alex Williamson)
 
  - Make use of ERR_CAST() for error return (Dan Carpenter)
 
  - Fix vfio_group release deadlock from iommu notifier (Alex Williamson)
 
  - Unset KVM-VFIO attributes only on group match (Alex Williamson)
 
  - Fix release path group/file matching with KVM-VFIO (Alex Williamson)
 
  - Remove unnecessary lock uses triggering lockdep splat (Alex Williamson)
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Merge tag 'vfio-v4.13-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - Include Intel XXV710 in INTx workaround (Alex Williamson)

 - Make use of ERR_CAST() for error return (Dan Carpenter)

 - Fix vfio_group release deadlock from iommu notifier (Alex Williamson)

 - Unset KVM-VFIO attributes only on group match (Alex Williamson)

 - Fix release path group/file matching with KVM-VFIO (Alex Williamson)

 - Remove unnecessary lock uses triggering lockdep splat (Alex Williamson)

* tag 'vfio-v4.13-rc1' of git://github.com/awilliam/linux-vfio:
  vfio: Remove unnecessary uses of vfio_container.group_lock
  vfio: New external user group/file match
  kvm-vfio: Decouple only when we match a group
  vfio: Fix group release deadlock
  vfio: Use ERR_CAST() instead of open coding it
  vfio/pci: Add Intel XXV710 to hidden INTx devices
2017-07-13 12:23:54 -07:00
Alex Williamson 5d6dee80a1 vfio: New external user group/file match
At the point where the kvm-vfio pseudo device wants to release its
vfio group reference, we can't always acquire a new reference to make
that happen.  The group can be in a state where we wouldn't allow a
new reference to be added.  This new helper function allows a caller
to match a file to a group to facilitate this.  Given a file and
group, report if they match.  Thus the caller needs to already have a
group reference to match to the file.  This allows the deletion of a
group without acquiring a new reference.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Cc: stable@vger.kernel.org
2017-06-28 13:50:05 -06:00
Ingo Molnar ac6424b981 sched/wait: Rename wait_queue_t => wait_queue_entry_t
Rename:

	wait_queue_t		=>	wait_queue_entry_t

'wait_queue_t' was always a slight misnomer: its name implies that it's a "queue",
but in reality it's a queue *entry*. The 'real' queue is the wait queue head,
which had to carry the name.

Start sorting this out by renaming it to 'wait_queue_entry_t'.

This also allows the real structure name 'struct __wait_queue' to
lose its double underscore and become 'struct wait_queue_entry',
which is the more canonical nomenclature for such data types.

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-20 12:18:27 +02:00
Jike Song ccd46dbae7 vfio: support notifier chain in vfio_group
Beyond vfio_iommu events, users might also be interested in
vfio_group events. For example, if a vfio_group is used along
with Qemu/KVM, whenever kvm pointer is set to/cleared from the
vfio_group, users could be notified.

Currently only VFIO_GROUP_NOTIFY_SET_KVM supported.

Cc: Kirti Wankhede <kwankhede@nvidia.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Jike Song <jike.song@intel.com>
[aw: remove use of new typedef]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-12-01 10:40:05 -07:00
Jike Song 22195cbd34 vfio: vfio_register_notifier: classify iommu notifier
Currently vfio_register_notifier assumes that there is only one
notifier chain, which is in vfio_iommu. However, the user might
also be interested in events other than vfio_iommu, for example,
vfio_group. Refactor vfio_{un}register_notifier implementation
to make it feasible.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Jike Song <jike.song@intel.com>
[aw: merge with commit 816ca69ea9c7 ("vfio: Fix handling of error returned by 'vfio_group_get_from_dev()'"), remove typedef]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-12-01 09:38:47 -07:00
Kirti Wankhede c747f08aea vfio: Introduce vfio_set_irqs_validate_and_prepare()
Vendor driver using mediated device framework would use same mechnism to
validate and prepare IRQs. Introducing this function to reduce code
replication in multiple drivers.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17 08:33:20 -07:00
Kirti Wankhede b3c0a866f1 vfio: Introduce common function to add capabilities
Vendor driver using mediated device framework should use
vfio_info_add_capability() to add capabilities.
Introduced this function to reduce code duplication in vendor drivers.

vfio_info_cap_shift() manipulated a data buffer to add an offset to each
element in a chain. This data buffer is documented in a uapi header.
Changing vfio_info_cap_shift symbol to be available to all drivers.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17 08:33:20 -07:00
Kirti Wankhede c086de818d vfio iommu: Add blocking notifier to notify DMA_UNMAP
Added blocking notifier to IOMMU TYPE1 driver to notify vendor drivers
about DMA_UNMAP.
Exported two APIs vfio_register_notifier() and vfio_unregister_notifier().
Notifier should be registered, if external user wants to use
vfio_pin_pages()/vfio_unpin_pages() APIs to pin/unpin pages.
Vendor driver should use VFIO_IOMMU_NOTIFY_DMA_UNMAP action to invalidate
mappings.

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17 08:33:07 -07:00
Kirti Wankhede 2169037dc3 vfio iommu: Added pin and unpin callback functions to vfio_iommu_driver_ops
Added APIs for pining and unpining set of pages. These call back into
backend iommu module to actually pin and unpin pages.
Added two new callback functions to struct vfio_iommu_driver_ops. Backend
IOMMU module that supports pining and unpinning pages for mdev devices
should provide these functions.

Renamed static functions in vfio_type1_iommu.c to resolve conflicts

Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Neo Jia <cjia@nvidia.com>
Reviewed-by: Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-11-17 08:24:58 -07:00
Alex Williamson d7a8d5ed87 vfio: Add capability chain helpers
Allow sub-modules to easily reallocate a buffer for managing
capability chains for info ioctls.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2016-02-22 16:10:08 -07:00
Alex Williamson 03a76b60f8 vfio: Include No-IOMMU mode
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>
2015-12-21 15:28:11 -07:00
Alex Williamson ae5515d663 Revert: "vfio: Include No-IOMMU mode"
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>
2015-12-04 08:38:42 -07:00
Alex Williamson 033291eccb vfio: Include No-IOMMU mode
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>
2015-11-04 09:56:16 -07:00
Linus Torvalds 8c194f3bd3 VFIO updates for v4.1
- VFIO platform bus driver support (Baptiste Reynal, Antonios Motakis, testing and review by Eric Auger)
  - Split VFIO irqfd support to separate module (Alex Williamson)
  - vfio-pci VGA arbiter client (Alex Williamson)
  - New vfio-pci.ids= module option (Alex Williamson)
  - vfio-pci D3 power state support for idle devices (Alex Williamson)
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Merge tag 'vfio-v4.1-rc1' of git://github.com/awilliam/linux-vfio

Pull VFIO updates from Alex Williamson:

 - VFIO platform bus driver support (Baptiste Reynal, Antonios Motakis,
   testing and review by Eric Auger)

 - Split VFIO irqfd support to separate module (Alex Williamson)

 - vfio-pci VGA arbiter client (Alex Williamson)

 - New vfio-pci.ids= module option (Alex Williamson)

 - vfio-pci D3 power state support for idle devices (Alex Williamson)

* tag 'vfio-v4.1-rc1' of git://github.com/awilliam/linux-vfio: (30 commits)
  vfio-pci: Fix use after free
  vfio-pci: Move idle devices to D3hot power state
  vfio-pci: Remove warning if try-reset fails
  vfio-pci: Allow PCI IDs to be specified as module options
  vfio-pci: Add VGA arbiter client
  vfio-pci: Add module option to disable VGA region access
  vgaarb: Stub vga_set_legacy_decoding()
  vfio: Split virqfd into a separate module for vfio bus drivers
  vfio: virqfd_lock can be static
  vfio: put off the allocation of "minor" in vfio_create_group
  vfio/platform: implement IRQ masking/unmasking via an eventfd
  vfio: initialize the virqfd workqueue in VFIO generic code
  vfio: move eventfd support code for VFIO_PCI to a separate file
  vfio: pass an opaque pointer on virqfd initialization
  vfio: add local lock for virqfd instead of depending on VFIO PCI
  vfio: virqfd: rename vfio_pci_virqfd_init and vfio_pci_virqfd_exit
  vfio: add a vfio_ prefix to virqfd_enable and virqfd_disable and export
  vfio/platform: support for level sensitive interrupts
  vfio/platform: trigger an interrupt via eventfd
  vfio/platform: initial interrupts support code
  ...
2015-04-14 18:06:47 -07:00
Alex Williamson 71be3423a6 vfio: Split virqfd into a separate module for vfio bus drivers
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>
2015-03-17 08:33:38 -06:00
Denys Vlasenko 3876488444 include/stddef.h: Move offsetofend() from vfio.h to a generic kernel header
Suggested by Andy.

Suggested-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Will Drewry <wad@chromium.org>
Link: http://lkml.kernel.org/r/1425912738-559-1-git-send-email-dvlasenk@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-17 09:25:28 +01:00
Antonios Motakis 7e992d6927 vfio: move eventfd support code for VFIO_PCI to a separate file
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>
2015-03-16 14:08:54 -06:00
Alex Williamson 13060b64b8 vfio: Add and use device request op for vfio bus drivers
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>
2015-02-10 12:37:47 -07:00
Alexey Kardashevskiy 9b936c960f drivers/vfio: Enable VFIO if EEH is not supported
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>
2014-08-08 10:39:16 -06:00
Gavin Shan 92d18a6851 drivers/vfio: Fix EEH build error
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>
2014-08-08 10:36:20 -06:00
Gavin Shan 1b69be5e8a drivers/vfio: EEH support for VFIO PCI device
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>
2014-08-05 15:28:48 +10:00
Gavin Shan b13460b920 drivers/vfio: Rework offsetofend()
The macro offsetofend() introduces unnecessary temporary variable
"tmp". The patch avoids that and saves a bit memory in stack.

Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2014-05-30 11:35:54 -06:00