Without locking userspace can trigger a UAF by racing
KVM_DEV_VFIO_GROUP_DEL with VFIO_GROUP_GET_DEVICE_FD:
CPU1 CPU2
ioctl(KVM_DEV_VFIO_GROUP_DEL)
ioctl(VFIO_GROUP_GET_DEVICE_FD)
vfio_group_get_device_fd
open_device()
intel_vgpu_open_device()
vfio_register_notifier()
vfio_register_group_notifier()
blocking_notifier_call_chain(&group->notifier,
VFIO_GROUP_NOTIFY_SET_KVM, group->kvm);
set_kvm()
group->kvm = NULL
close()
kfree(kvm)
intel_vgpu_group_notifier()
vdev->kvm = data
[..]
kvm_get_kvm(vgpu->kvm);
// UAF!
Add a simple rwsem in the group to protect the kvm while the notifier is
using it.
Note this doesn't fix the race internal to i915 where userspace can
trigger two VFIO_GROUP_NOTIFY_SET_KVM's before we reach a consumer of
vgpu->kvm and trigger this same UAF, it just makes the notifier
self-consistent.
Fixes: ccd46dbae7 ("vfio: support notifier chain in vfio_group")
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Tested-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/1-v2-d035a1842d81+1bf-vfio_group_locking_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
VFIO PCI does a security check as part of hot reset to prove that the user
has permission to manipulate all the devices that will be impacted by the
reset.
Use a new API vfio_file_has_dev() to perform this security check against
the struct file directly and remove the vfio_group from VFIO PCI.
Since VFIO PCI was the last user of vfio_group_get_external_user() and
vfio_group_put_external_user() remove it as well.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/8-v3-f7729924a7ea+25e33-vfio_kvm_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Just change the argument from struct vfio_group to struct file *.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/6-v3-f7729924a7ea+25e33-vfio_kvm_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Instead of a general extension check change the function into a limited
test if the iommu_domain has enforced coherency, which is the only thing
kvm needs to query.
Make the new op self contained by properly refcounting the container
before touching it.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/5-v3-f7729924a7ea+25e33-vfio_kvm_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio_group_fops_open() ensures there is only ever one struct file open for
any struct vfio_group at any time:
/* Do we need multiple instances of the group open? Seems not. */
opened = atomic_cmpxchg(&group->opened, 0, 1);
if (opened) {
vfio_group_put(group);
return -EBUSY;
Therefor the struct file * can be used directly to search the list of VFIO
groups that KVM keeps instead of using the
vfio_external_group_match_file() callback to try to figure out if the
passed in FD matches the list or not.
Delete vfio_external_group_match_file().
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/4-v3-f7729924a7ea+25e33-vfio_kvm_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The only caller wants to get a pointer to the struct iommu_group
associated with the VFIO group file. Instead of returning the group ID
then searching sysfs for that string to get the struct iommu_group just
directly return the iommu_group pointer already held by the vfio_group
struct.
It already has a safe lifetime due to the struct file kref, the vfio_group
and thus the iommu_group cannot be destroyed while the group file is open.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v3-f7729924a7ea+25e33-vfio_kvm_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that the iommu core takes care of isolation there is no race between
driver attach and container unset. Once iommu_group_release_dma_owner()
returns the device can immediately be re-used.
Remove this mechanism.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/0-v1-a1e8791d795b+6b-vfio_container_q_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The last user of this function is in PCI callbacks that want to convert
their struct pci_dev to a vfio_device. Instead of searching use the
vfio_device available trivially through the drvdata.
When a callback in the device_driver is called, the caller must hold the
device_lock() on dev. The purpose of the device_lock is to prevent
remove() from being called (see __device_release_driver), and allow the
driver to safely interact with its drvdata without races.
The PCI core correctly follows this and holds the device_lock() when
calling error_detected (see report_error_detected) and
sriov_configure (see sriov_numvfs_store).
Further, since the drvdata holds a positive refcount on the vfio_device
any access of the drvdata, under the device_lock(), from a driver callback
needs no further protection or refcounting.
Thus the remark in the vfio_device_get_from_dev() comment does not apply
here, VFIO PCI drivers all call vfio_unregister_group_dev() from their
remove callbacks under the device_lock() and cannot race with the
remaining callers.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/2-v4-c841817a0349+8f-vfio_get_from_dev_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Having a consistent pointer in the drvdata will allow the next patch to
make use of the drvdata from some of the core code helpers.
Use a WARN_ON inside vfio_pci_core_register_device() to detect drivers
that miss this.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1-v4-c841817a0349+8f-vfio_get_from_dev_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
When the open_device() op is called the container_users is incremented and
held incremented until close_device(). Thus, so long as drivers call
functions within their open_device()/close_device() region they do not
need to worry about the container_users.
These functions can all only be called between open_device() and
close_device():
vfio_pin_pages()
vfio_unpin_pages()
vfio_dma_rw()
vfio_register_notifier()
vfio_unregister_notifier()
Eliminate the calls to vfio_group_add_container_user() and add
vfio_assert_device_open() to detect driver mis-use. This causes the
close_device() op to check device->open_count so always leave it elevated
while calling the op.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/7-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that callers have been updated to use the vfio_device APIs the driver
facing group interface is no longer used, delete it:
- vfio_group_get_external_user_from_dev()
- vfio_group_pin_pages()
- vfio_group_unpin_pages()
- vfio_group_iommu_domain()
--
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/6-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Every caller has a readily available vfio_device pointer, use that instead
of passing in a generic struct device. Change vfio_dma_rw() to take in the
struct vfio_device and move the container users that would have been held
by vfio_group_get_external_user_from_dev() to vfio_dma_rw() directly, like
vfio_pin/unpin_pages().
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/4-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Every caller has a readily available vfio_device pointer, use that instead
of passing in a generic struct device. The struct vfio_device already
contains the group we need so this avoids complexity, extra refcountings,
and a confusing lifecycle model.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
All callers have a struct vfio_device trivially available, pass it in
directly and avoid calling the expensive vfio_group_get_from_dev().
Acked-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Jason J. Herne <jjherne@linux.ibm.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1-v4-8045e76bf00b+13d-vfio_mdev_no_group_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
IOMMU groups have been mandatory for some time now, so a device without
one is necessarily a device without any usable IOMMU, therefore the
iommu_present() check is redundant (or at best unhelpful).
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/537103bbd7246574f37f2c88704d7824a3a889f2.1649160714.git.robin.murphy@arm.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
From Yishai:
This series improves mlx5 live migration driver in few aspects as of
below.
Refactor to enable running migration commands in parallel over the PF
command interface.
To achieve that we exposed from mlx5_core an API to let the VF be
notified before that the PF command interface goes down/up. (e.g. PF
reload upon health recovery).
Once having the above functionality in place mlx5 vfio doesn't need any
more to obtain the global PF lock upon using the command interface but
can rely on the above mechanism to be in sync with the PF.
This can enable parallel VFs migration over the PF command interface
from kernel driver point of view.
In addition,
Moved to use the PF async command mode for the SAVE state command.
This enables returning earlier to user space upon issuing successfully
the command and improve latency by let things run in parallel.
Alex, as this series touches mlx5_core we may need to send this in a
pull request format to VFIO to avoid conflicts before acceptance.
Link: https://lore.kernel.org/all/20220510090206.90374-1-yishaih@nvidia.com
Signed-of-by: Leon Romanovsky <leonro@nvidia.com>
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Merge tag 'mlx5-lm-parallel' of https://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux into v5.19/vfio/next
Improve mlx5 live migration driver
From Yishai:
This series improves mlx5 live migration driver in few aspects as of
below.
Refactor to enable running migration commands in parallel over the PF
command interface.
To achieve that we exposed from mlx5_core an API to let the VF be
notified before that the PF command interface goes down/up. (e.g. PF
reload upon health recovery).
Once having the above functionality in place mlx5 vfio doesn't need any
more to obtain the global PF lock upon using the command interface but
can rely on the above mechanism to be in sync with the PF.
This can enable parallel VFs migration over the PF command interface
from kernel driver point of view.
In addition,
Moved to use the PF async command mode for the SAVE state command.
This enables returning earlier to user space upon issuing successfully
the command and improve latency by let things run in parallel.
Alex, as this series touches mlx5_core we may need to send this in a
pull request format to VFIO to avoid conflicts before acceptance.
Link: https://lore.kernel.org/all/20220510090206.90374-1-yishaih@nvidia.com
Signed-of-by: Leon Romanovsky <leonro@nvidia.com>
Use the PF asynchronous command mode for the SAVE state command.
This enables returning earlier to user space upon issuing successfully
the command and improve latency by let things run in parallel.
Link: https://lore.kernel.org/r/20220510090206.90374-5-yishaih@nvidia.com
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Refactor to enable different VFs to run their commands over the PF
command interface in parallel and to not block one each other.
This is done by not using the global PF lock that was used before but
relying on the VF attach/detach mechanism to sync.
Link: https://lore.kernel.org/r/20220510090206.90374-4-yishaih@nvidia.com
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Manage the VF attach/detach callback from the PF.
This lets the driver to enable parallel VFs migration as will be
introduced in the next patch.
As part of this, reorganize the VF is migratable code to be in a
separate function and rename it to be set_migratable() to match its
functionality.
Link: https://lore.kernel.org/r/20220510090206.90374-3-yishaih@nvidia.com
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
drm/i915 feature pull #2 for v5.19:
Features and functionality:
- Add first set of DG2 PCI IDs for "motherboard down" designs (Matt Roper)
- Add initial RPL-P PCI IDs as ADL-P subplatform (Matt Atwood)
Refactoring and cleanups:
- Power well refactoring and cleanup (Imre)
- GVT-g refactor and mdev API cleanup (Christoph, Jason, Zhi)
- DPLL refactoring and cleanup (Ville)
- VBT panel specific data parsing cleanup (Ville)
- Use drm_mode_init() for on-stack modes (Ville)
Fixes:
- Fix PSR state pipe A/B confusion by clearing more state on disable (José)
- Fix FIFO underruns caused by not taking DRAM channel into account (Vinod)
- Fix FBC flicker on display 11+ by enabling a workaround (José)
- Fix VBT seamless DRRS min refresh rate check (Ville)
- Fix panel type assumption on bogus VBT data (Ville)
- Fix panel data parsing for VBT that misses panel data pointers block (Ville)
- Fix spurious AUX timeout/hotplug handling on LTTPR links (Imre)
Merges:
- Backmerge drm-next (Jani)
- GVT changes (Jani)
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87bkwbkkdo.fsf@intel.com
IOMMU_CACHE means that normal DMAs do not require any additional coherency
mechanism and is the basic uAPI that VFIO exposes to userspace. For
instance VFIO applications like DPDK will not work if additional coherency
operations are required.
Therefore check IOMMU_CAP_CACHE_COHERENCY like vdpa & usnic do before
allowing an IOMMU backed VFIO device to be created.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/4-v3-2cf356649677+a32-intel_no_snoop_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
IOMMU_CACHE means "normal DMA to this iommu_domain's IOVA should be cache
coherent" and is used by the DMA API. The definition allows for special
non-coherent DMA to exist - ie processing of the no-snoop flag in PCIe
TLPs - so long as this behavior is opt-in by the device driver.
The flag is mainly used by the DMA API to synchronize the IOMMU setting
with the expected cache behavior of the DMA master. eg based on
dev_is_dma_coherent() in some case.
For Intel IOMMU IOMMU_CACHE was redefined to mean 'force all DMA to be
cache coherent' which has the practical effect of causing the IOMMU to
ignore the no-snoop bit in a PCIe TLP.
x86 platforms are always IOMMU_CACHE, so Intel should ignore this flag.
Instead use the new domain op enforce_cache_coherency() which causes every
IOPTE created in the domain to have the no-snoop blocking behavior.
Reconfigure VFIO to always use IOMMU_CACHE and call
enforce_cache_coherency() to operate the special Intel behavior.
Remove the IOMMU_CACHE test from Intel IOMMU.
Ultimately VFIO plumbs the result of enforce_cache_coherency() back into
the x86 platform code through kvm_arch_register_noncoherent_dma() which
controls if the WBINVD instruction is available in the guest. No other
archs implement kvm_arch_register_noncoherent_dma() nor are there any
other known consumers of VFIO_DMA_CC_IOMMU that might be affected by the
user visible result change on non-x86 archs.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/2-v3-2cf356649677+a32-intel_no_snoop_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The iommu core and driver core have been enhanced to avoid unsafe driver
binding to a live group after iommu_group_set_dma_owner(PRIVATE_USER)
has been called. There's no need to register iommu group notifier. This
removes the iommu group notifer which contains BUG_ON() and WARN().
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20220418005000.897664-11-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
commit 60720a0fc6 ("vfio: Add device tracking during unbind") added the
unbound list to plug a problem with KVM where KVM_DEV_VFIO_GROUP_DEL
relied on vfio_group_get_external_user() succeeding to return the
vfio_group from a group file descriptor. The unbound list allowed
vfio_group_get_external_user() to continue to succeed in edge cases.
However commit 5d6dee80a1 ("vfio: New external user group/file match")
deleted the call to vfio_group_get_external_user() during
KVM_DEV_VFIO_GROUP_DEL. Instead vfio_external_group_match_file() is used
to directly match the file descriptor to the group pointer.
This in turn avoids the call down to vfio_dev_viable() during
KVM_DEV_VFIO_GROUP_DEL and also avoids the trouble the first commit was
trying to fix.
There are no other users of vfio_dev_viable() that care about the time
after vfio_unregister_group_dev() returns, so simply delete the
unbound_list entirely.
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20220418005000.897664-10-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
As DMA ownership is claimed for the iommu group when a VFIO group is
added to a VFIO container, the VFIO group viability is guaranteed as long
as group->container_users > 0. Remove those unnecessary group viability
checks which are only hit when group->container_users is not zero.
The only remaining reference is in GROUP_GET_STATUS, which could be called
at any time when group fd is valid. Here we just replace the
vfio_group_viable() by directly calling IOMMU core to get viability status.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20220418005000.897664-9-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Claim group dma ownership when an IOMMU group is set to a container,
and release the dma ownership once the iommu group is unset from the
container.
This change disallows some unsafe bridge drivers to bind to non-ACS
bridges while devices under them are assigned to user space. This is an
intentional enhancement and possibly breaks some existing
configurations. The recommendation to such an affected user would be
that the previously allowed host bridge driver was unsafe for this use
case and to continue to enable assignment of devices within that group,
the driver should be unbound from the bridge device or replaced with the
pci-stub driver.
For any bridge driver, we consider it unsafe if it satisfies any of the
following conditions:
1) The bridge driver uses DMA. Calling pci_set_master() or calling any
kernel DMA API (dma_map_*() and etc.) is an indicate that the
driver is doing DMA.
2) If the bridge driver uses MMIO, it should be tolerant to hostile
userspace also touching the same MMIO registers via P2P DMA
attacks.
If the bridge driver turns out to be a safe one, it could be used as
before by setting the driver's .driver_managed_dma field, just like what
we have done in the pcieport driver.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Link: https://lore.kernel.org/r/20220418005000.897664-8-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The device creator is supposed to use the dev.groups value to add sysfs
files before device_add is called, not call sysfs_create_files() after
device_add() returns. This creates a race with uevent delivery where the
extra attribute will not be visible.
This was being done because the groups had been co-opted by the mdev
driver, now that prior patches have moved the driver's groups to the
struct device_driver the dev.group is properly free for use here.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-34-hch@lst.de
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
The last useful member in this struct is the supported_type_groups, move
it to the mdev_driver and delete mdev_parent_ops.
Replace it with mdev_driver as an argument to mdev_register_device()
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-33-hch@lst.de
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
This is only used by one sample to print a fixed string that is pointless.
In general, having a device driver attach sysfs attributes to the parent
is horrific. This should never happen, and always leads to some kind of
liftime bug as it become very difficult for the sysfs attribute to go back
to any data owned by the device driver.
Remove the general mechanism to create this abuse.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-32-hch@lst.de
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Now that all mdev drivers directly create their own mdev_device driver and
directly register with the vfio core's vfio_device_ops this is all dead
code.
Delete vfio_mdev.c and the mdev_parent_ops members that are connected to
it.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20220411141403.86980-31-hch@lst.de
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
get_pf_vdev() tries to check if a PF is a VFIO PF by looking at the driver:
if (pci_dev_driver(physfn) != pci_dev_driver(vdev->pdev)) {
However now that we have multiple VF and PF drivers this is no longer
reliable.
This means that security tests realted to vf_token can be skipped by
mixing and matching different VFIO PCI drivers.
Instead of trying to use the driver core to find the PF devices maintain a
linked list of all PF vfio_pci_core_device's that we have called
pci_enable_sriov() on.
When registering a VF just search the list to see if the PF is present and
record the match permanently in the struct. PCI core locking prevents a PF
from passing pci_disable_sriov() while VF drivers are attached so the VFIO
owned PF becomes a static property of the VF.
In common cases where vfio does not own the PF the global list remains
empty and the VF's pointer is statically NULL.
This also fixes a lockdep splat from recursive locking of the
vfio_group::device_lock between vfio_device_get_from_name() and
vfio_device_get_from_dev(). If the VF and PF share the same group this
would deadlock.
Fixes: ff53edf6d6 ("vfio/pci: Split the pci_driver code out of vfio_pci_core.c")
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/0-v3-876570980634+f2e8-vfio_vf_token_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Register private handler for pci_error_handlers.reset_done and update
state accordingly.
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Longfang Liu <liulongfang@huawei.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20220308184902.2242-10-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
VMs assigned with HiSilicon ACC VF devices can now perform live migration
if the VF devices are bind to the hisi_acc_vfio_pci driver.
Just like ACC PF/VF drivers this VFIO driver also make use of the HiSilicon
QM interface. QM stands for Queue Management which is a generic IP used by
ACC devices. It provides a generic PCIe interface for the CPU and the ACC
devices to share a group of queues.
QM integrated into an accelerator provides queue management service.
Queues can be assigned to PF and VFs, and queues can be controlled by
unified mailboxes and doorbells.
The QM driver (drivers/crypto/hisilicon/qm.c) provides generic
interfaces to ACC drivers to manage the QM.
Signed-off-by: Longfang Liu <liulongfang@huawei.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Link: https://lore.kernel.org/r/20220308184902.2242-9-shameerali.kolothum.thodi@huawei.com
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
HiSilicon ACC VF device BAR2 region consists of both functional register
space and migration control register space. Unnecessarily exposing the
migration BAR region to the Guest has the potential to prevent/corrupt
the Guest migration.
Hence, introduce a separate struct vfio_device_ops for migration support
which will override the ioctl/read/write/mmap methods to hide the
migration region and limit the Guest access only to the functional
register space.
This will be used in subsequent patches when we add migration support
to the driver.
Please note that it is OK to export the entire VF BAR if migration is
not supported or required as this cannot affect the PF configurations.
Reviewed-by: Longfang Liu <liulongfang@huawei.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220308184902.2242-6-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add a vendor-specific vfio_pci driver for HiSilicon ACC devices.
This will be extended in subsequent patches to add support for VFIO
live migration feature.
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220308184902.2242-5-shameerali.kolothum.thodi@huawei.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Register its own handler for pci_error_handlers.reset_done and update
state accordingly.
Link: https://lore.kernel.org/all/20220224142024.147653-16-yishaih@nvidia.com
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Expose vfio_pci_core_aer_err_detected() to be used by drivers as part of
their pci_error_handlers structure.
Next patch for mlx5 driver will use it.
Link: https://lore.kernel.org/all/20220224142024.147653-15-yishaih@nvidia.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>
This patch adds support for vfio_pci driver for mlx5 devices.
It uses vfio_pci_core to register to the VFIO subsystem and then
implements the mlx5 specific logic in the migration area.
The migration implementation follows the definition from uapi/vfio.h and
uses the mlx5 VF->PF command channel to achieve it.
This patch implements the suspend/resume flows.
Link: https://lore.kernel.org/all/20220224142024.147653-14-yishaih@nvidia.com
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Expose migration commands over the device, it includes: suspend, resume,
get vhca id, query/save/load state.
As part of this adds the APIs and data structure that are needed to manage
the migration data.
Link: https://lore.kernel.org/all/20220224142024.147653-13-yishaih@nvidia.com
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
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>
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>
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>
If 'vfio_pci_core_device::needs_pm_restore' is set (PCI device does
not have No_Soft_Reset bit set in its PMCSR config register), then the
current PCI state will be saved locally in
'vfio_pci_core_device::pm_save' during D0->D3hot transition and same
will be restored back during D3hot->D0 transition. For reset-related
functionalities, vfio driver uses PCI reset API's. These
API's internally change the PCI power state back to D0 first if
the device power state is non-D0. This state change to D0 will happen
without the involvement of vfio driver.
Let's consider the following example:
1. The device is in D3hot.
2. User invokes VFIO_DEVICE_RESET ioctl.
3. pci_try_reset_function() will be called which internally
invokes pci_dev_save_and_disable().
4. pci_set_power_state(dev, PCI_D0) will be called first.
5. pci_save_state() will happen then.
Now, for the devices which has NoSoftRst-, the pci_set_power_state()
can trigger soft reset and the original PCI config state will be lost
at step (4) and this state cannot be restored again. This original PCI
state can include any setting which is performed by SBIOS or host
linux kernel (for example LTR, ASPM L1 substates, etc.). When this
soft reset will be triggered, then all these settings will be reset,
and the device state saved at step (5) will also have this setting
cleared so it cannot be restored. Since the vfio driver only exposes
limited PCI capabilities to its user, so the vfio driver user also
won't have the option to save and restore these capabilities state
either and these original settings will be permanently lost.
For pci_reset_bus() also, we can have the above situation.
The other functions/devices can be in D3hot and the reset will change
the power state of all devices to D0 without the involvement of vfio
driver.
So, before calling any reset-related API's, we need to make sure that
the device state is D0. This is mainly to preserve the state around
soft reset.
For vfio_pci_core_disable(), we use __pci_reset_function_locked()
which internally can use pci_pm_reset() for the function reset.
pci_pm_reset() requires the device power state to be in D0, otherwise
it returns error.
This patch changes the device power state to D0 by invoking
vfio_pci_set_power_state() explicitly before calling any reset related
API's.
Fixes: 51ef3a004b ("vfio/pci: Restore device state on PM transition")
Signed-off-by: Abhishek Sahu <abhsahu@nvidia.com>
Link: https://lore.kernel.org/r/20220217122107.22434-3-abhsahu@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
If 'vfio_pci_core_device::needs_pm_restore' is set (PCI device does
not have No_Soft_Reset bit set in its PMCSR config register), then
the current PCI state will be saved locally in
'vfio_pci_core_device::pm_save' during D0->D3hot transition and same
will be restored back during D3hot->D0 transition.
For saving the PCI state locally, pci_store_saved_state() is being
used and the pci_load_and_free_saved_state() will free the allocated
memory.
But for reset related IOCTLs, vfio driver calls PCI reset-related
API's which will internally change the PCI power state back to D0. So,
when the guest resumes, then it will get the current state as D0 and it
will skip the call to vfio_pci_set_power_state() for changing the
power state to D0 explicitly. In this case, the memory pointed by
'pm_save' will never be freed. In a malicious sequence, the state changing
to D3hot followed by VFIO_DEVICE_RESET/VFIO_DEVICE_PCI_HOT_RESET can be
run in a loop and it can cause an OOM situation.
This patch frees the earlier allocated memory first before overwriting
'pm_save' to prevent the mentioned memory leak.
Fixes: 51ef3a004b ("vfio/pci: Restore device state on PM transition")
Signed-off-by: Abhishek Sahu <abhsahu@nvidia.com>
Link: https://lore.kernel.org/r/20220217122107.22434-2-abhsahu@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Variables allocated by kvzalloc should not be freed by kfree.
Because they may be allocated by vmalloc.
So we replace kfree with kvfree here.
Fixes: d6a4c18566 ("vfio iommu: Implementation of ioctl for dirty pages tracking")
Signed-off-by: Jiacheng Shi <billsjc@sjtu.edu.cn>
Link: https://lore.kernel.org/r/20211212091600.2560-1-billsjc@sjtu.edu.cn
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Sparse warns:
sparse warnings: (new ones prefixed by >>)
>> drivers/vfio/pci/vfio_pci_igd.c:146:21: sparse: sparse: incorrect type in assignment (different base types) @@ expected unsigned short [addressable] [usertype] val @@ got restricted __le16 [usertype] @@
drivers/vfio/pci/vfio_pci_igd.c:146:21: sparse: expected unsigned short [addressable] [usertype] val
drivers/vfio/pci/vfio_pci_igd.c:146:21: sparse: got restricted __le16 [usertype]
>> drivers/vfio/pci/vfio_pci_igd.c:161:21: sparse: sparse: incorrect type in assignment (different base types) @@ expected unsigned int [addressable] [usertype] val @@ got restricted __le32 [usertype] @@
drivers/vfio/pci/vfio_pci_igd.c:161:21: sparse: expected unsigned int [addressable] [usertype] val
drivers/vfio/pci/vfio_pci_igd.c:161:21: sparse: got restricted __le32 [usertype]
drivers/vfio/pci/vfio_pci_igd.c:176:21: sparse: sparse: incorrect type in assignment (different base types) @@ expected unsigned short [addressable] [usertype] val @@ got restricted __le16 [usertype] @@
drivers/vfio/pci/vfio_pci_igd.c:176:21: sparse: expected unsigned short [addressable] [usertype] val
drivers/vfio/pci/vfio_pci_igd.c:176:21: sparse: got restricted __le16 [usertype]
These are due to trying to use an unsigned to store the result of
a cpu_to_leXX() conversion. These are small variables, so pointer
tricks are wasteful and casting just generates different sparse
warnings. Store to and copy results from a separate little endian
variable.
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/r/202111290026.O3vehj03-lkp@intel.com/
Link: https://lore.kernel.org/r/163840226123.138003.7668320168896210328.stgit@omen
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Storing a pointer to the MSI descriptor just to track the Linux interrupt
number is daft. Just store the interrupt number and be done with it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20211210221815.207838579@linutronix.de
This is to fix incorrect pointer arithmetic which caused wrong
OpRegion version returned, then VM driver got error to get wanted
VBT block. We need to be safe to return correct data, so force
pointer type for byte access.
Fixes: 49ba1a2976 ("vfio/pci: Add OpRegion 2.0+ Extended VBT support.")
Cc: Colin Xu <colin.xu@gmail.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Dmitry Torokhov <dtor@chromium.org>
Cc: "Xu, Terrence" <terrence.xu@intel.com>
Cc: "Gao, Fred" <fred.gao@intel.com>
Acked-by: Colin Xu <colin.xu@gmail.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: https://lore.kernel.org/r/20211125051328.3359902-1-zhenyuw@linux.intel.com
[aw: line wrap]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio.c abuses (misuses) "/**", which indicates the beginning of
kernel-doc notation in the kernel tree. This causes a bunch of
kernel-doc complaints about this source file, so quieten all of
them by changing all "/**" to "/*".
vfio.c:236: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* IOMMU driver registration
vfio.c:236: warning: missing initial short description on line:
* IOMMU driver registration
vfio.c:295: warning: expecting prototype for Container objects(). Prototype was for vfio_container_get() instead
vfio.c:317: warning: expecting prototype for Group objects(). Prototype was for __vfio_group_get_from_iommu() instead
vfio.c:496: warning: Function parameter or member 'device' not described in 'vfio_device_put'
vfio.c:496: warning: expecting prototype for Device objects(). Prototype was for vfio_device_put() instead
vfio.c:599: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Async device support
vfio.c:599: warning: missing initial short description on line:
* Async device support
vfio.c:693: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* VFIO driver API
vfio.c:693: warning: missing initial short description on line:
* VFIO driver API
vfio.c:835: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Get a reference to the vfio_device for a device. Even if the
vfio.c:835: warning: missing initial short description on line:
* Get a reference to the vfio_device for a device. Even if the
vfio.c:969: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* VFIO base fd, /dev/vfio/vfio
vfio.c:969: warning: missing initial short description on line:
* VFIO base fd, /dev/vfio/vfio
vfio.c:1187: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* VFIO Group fd, /dev/vfio/$GROUP
vfio.c:1187: warning: missing initial short description on line:
* VFIO Group fd, /dev/vfio/$GROUP
vfio.c:1540: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* VFIO Device fd
vfio.c:1540: warning: missing initial short description on line:
* VFIO Device fd
vfio.c:1615: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* External user API, exported by symbols to be linked dynamically.
vfio.c:1615: warning: missing initial short description on line:
* External user API, exported by symbols to be linked dynamically.
vfio.c:1663: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* External user API, exported by symbols to be linked dynamically.
vfio.c:1663: warning: missing initial short description on line:
* External user API, exported by symbols to be linked dynamically.
vfio.c:1742: warning: Function parameter or member 'caps' not described in 'vfio_info_cap_add'
vfio.c:1742: warning: Function parameter or member 'size' not described in 'vfio_info_cap_add'
vfio.c:1742: warning: Function parameter or member 'id' not described in 'vfio_info_cap_add'
vfio.c:1742: warning: Function parameter or member 'version' not described in 'vfio_info_cap_add'
vfio.c:1742: warning: expecting prototype for Sub(). Prototype was for vfio_info_cap_add() instead
vfio.c:2276: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
* Module/class support
vfio.c:2276: warning: missing initial short description on line:
* Module/class support
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Cornelia Huck <cohuck@redhat.com>
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/38a9cb92-a473-40bf-b8f9-85cc5cfc2da4@infradead.org
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Modernize how vfio is creating the group char dev and sysfs presence.
These days drivers with state should use cdev_device_add() and
cdev_device_del() to manage the cdev and sysfs lifetime.
This API requires the driver to put the struct device and struct cdev
inside its state struct (vfio_group), and then use the usual
device_initialize()/cdev_device_add()/cdev_device_del() sequence.
Split the code to make this possible:
- vfio_group_alloc()/vfio_group_release() are pair'd functions to
alloc/free the vfio_group. release is done under the struct device
kref.
- vfio_create_group()/vfio_group_put() are pairs that manage the
sysfs/cdev lifetime. Once the uses count is zero the vfio group's
userspace presence is destroyed.
- The IDR is replaced with an IDA. container_of(inode->i_cdev)
is used to get back to the vfio_group during fops open. The IDA
assigns unique minor numbers.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/5-v3-2fdfe4ca2cc6+18c-vfio_group_cdev_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The next patch adds a struct device to the struct vfio_group, and it is
confusing/bad practice to have two krefs in the same struct. This kref is
controlling the period when the vfio_group is registered in sysfs, and
visible in the internal lookup. Switch it to a refcount_t instead.
The refcount_dec_and_mutex_lock() is still required because we need
atomicity of the list searches and sysfs presence.
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/4-v3-2fdfe4ca2cc6+18c-vfio_group_cdev_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
If vfio_create_group() searches the group list and returns an already
existing group it does not put back the iommu_group reference that the
caller passed in.
Change the semantic of vfio_create_group() to not move the reference in
from the caller, but instead obtain a new reference inside and leave the
caller's reference alone. The two callers must now call iommu_group_put().
This is an unlikely race as the only caller that could hit it has already
searched the group list before attempting to create the group.
Fixes: cba3345cc4 ("vfio: VFIO core")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v3-2fdfe4ca2cc6+18c-vfio_group_cdev_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Split vfio_group_get_from_iommu() into __vfio_group_get_from_iommu() so
that vfio_create_group() can call it to consolidate this duplicated code.
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/2-v3-2fdfe4ca2cc6+18c-vfio_group_cdev_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
iommu_group_register_notifier()/iommu_group_unregister_notifier() are
built using a blocking_notifier_chain which integrates a rwsem. The
notifier function cannot be running outside its registration.
When considering how the notifier function interacts with create/destroy
of the group there are two fringe cases, the notifier starts before
list_add(&vfio.group_list) and the notifier runs after the kref
becomes 0.
Prior to vfio_create_group() unlocking and returning we have
container_users == 0
device_list == empty
And this cannot change until the mutex is unlocked.
After the kref goes to zero we must also have
container_users == 0
device_list == empty
Both are required because they are balanced operations and a 0 kref means
some caller became unbalanced. Add the missing assertion that
container_users must be zero as well.
These two facts are important because when checking each operation we see:
- IOMMU_GROUP_NOTIFY_ADD_DEVICE
Empty device_list avoids the WARN_ON in vfio_group_nb_add_dev()
0 container_users ends the call
- IOMMU_GROUP_NOTIFY_BOUND_DRIVER
0 container_users ends the call
Finally, we have IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER, which only deletes
items from the unbound list. During creation this list is empty, during
kref == 0 nothing can read this list, and it will be freed soon.
Since the vfio_group_release() doesn't hold the appropriate lock to
manipulate the unbound_list and could race with the notifier, move the
cleanup to directly before the kfree.
This allows deleting all of the deferred group put code.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Liu Yi L <yi.l.liu@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/1-v3-2fdfe4ca2cc6+18c-vfio_group_cdev_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Due to historical reason, some legacy shipped system doesn't follow
OpRegion 2.1 spec but still stick to OpRegion 2.0, in which the extended
VBT is not contiguous after OpRegion in physical address, but any
location pointed by RVDA via absolute address. Also although current
OpRegion 2.1+ systems appears that the extended VBT follows OpRegion,
RVDA is the relative address to OpRegion head, the extended VBT location
may change to non-contiguous to OpRegion. In both cases, it's impossible
to map a contiguous range to hold both OpRegion and the extended VBT and
expose via one vfio region.
The only difference between OpRegion 2.0 and 2.1 is where extended
VBT is stored: For 2.0, RVDA is the absolute address of extended VBT
while for 2.1, RVDA is the relative address of extended VBT to OpRegion
baes, and there is no other difference between OpRegion 2.0 and 2.1.
To support the non-contiguous region case as described, the updated read
op will patch OpRegion version and RVDA on-the-fly accordingly. So that
from vfio igd OpRegion view, only 2.1+ with contiguous extended VBT
after OpRegion is exposed, regardless the underneath host OpRegion is
2.0 or 2.1+. The mechanism makes it possible to support legacy OpRegion
2.0 extended VBT systems with on the market, and support OpRegion 2.1+
where the extended VBT isn't contiguous after OpRegion.
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Hang Yuan <hang.yuan@linux.intel.com>
Cc: Swee Yee Fonn <swee.yee.fonn@intel.com>
Cc: Fred Gao <fred.gao@intel.com>
Signed-off-by: Colin Xu <colin.xu@intel.com>
Link: https://lore.kernel.org/r/20211012124855.52463-1-colin.xu@gmail.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
IS_IOMMU_CAP_DOMAIN_IN_CONTAINER just obsfucated the checks being
performed, so open code it in the callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-16-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The external_domain concept rather misleading and not actually needed.
Replace it with a list of emulated groups in struct vfio_iommu.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-15-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Ensure pgsize_bitmap is always valid by initializing it to PAGE_MASK
in vfio_iommu_type1_open and remove the now pointless update for
the external domain case in vfio_iommu_type1_attach_group, which was
just setting pgsize_bitmap to PAGE_MASK when only external domains
were attached.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210924155705.4258-14-hch@lst.de
[aw: s/ULONG_MAX/PAGE_MASK/ per discussion in link]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Unlike the the type1 IOMMU backend, the SPAPR one does not contain any
support for the magic non-IOMMU backed iommu_group used by mediated
devices, so reject them in ->attach_group.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-13-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Pass the group flags to ->attach_group and remove the messy check for
the bus type.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-12-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The iommu_device field in struct mdev_device has never been used
since it was added more than 2 years ago.
This is a manual revert of commit 7bd50f0cd2
("vfio/type1: Add domain at(de)taching group helpers").
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-11-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Create a new private drivers/vfio/vfio.h header for the interface between
the VFIO core and the iommu drivers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-10-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The read, write and mmap methods are never implemented, so remove them.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-9-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reuse the logic in vfio_noiommu_group_alloc to allocate a fake
single-device iommu group for mediated devices by factoring out a common
function, and replacing the noiommu boolean field in struct vfio_group
with an enum to distinguish the three different kinds of groups.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-8-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Just pass a noiommu argument to vfio_create_group and set up the
->noiommu flag directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-7-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Split the actual noiommu group creation from vfio_iommu_group_get into a
new helper, and open code the rest of vfio_iommu_group_get in its only
caller. This creates an entirely separate and clear code path for the
noiommu group creation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-6-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Factor out a helper to find or allocate the vfio_group to reduce the
spagetthi code in vfio_register_group_dev a little.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-5-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio_noiommu_attach_group has two callers:
1) __vfio_container_attach_groups is called by vfio_ioctl_set_iommu,
which just called vfio_iommu_driver_allowed
2) vfio_group_set_container requires already checks ->noiommu on the
vfio_group, which is propagated from the iommudata in
vfio_create_group
so this check is entirely superflous and can be removed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-4-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Factor out a little helper to make the checks for the noiommu driver less
ugly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-3-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
We don't need to hold a reference to the group in the driver as well as
obtain a reference to the same group as the first thing
vfio_register_group_dev() does.
Since the drivers never use the group move this all into the core code.
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-2-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently when a fsl-mc device is reset, the entire DPRC container
is reset which is very inefficient because the devices within a
container will be reset multiple times.
Add support for individually resetting a device.
Signed-off-by: Diana Craciun <diana.craciun@oss.nxp.com>
Reviewed-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Link: https://lore.kernel.org/r/20210922110530.24736-2-diana.craciun@oss.nxp.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The function prototype is missing an identifier name. Add one.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20210902212631.54260-1-colin.king@canonical.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
- Fix dma-valid return WAITED implementation (Anthony Yznaga)
- SPDX license cleanups (Cai Huoqing)
- Split vfio-pci-core from vfio-pci and enhance PCI driver matching
to support future vendor provided vfio-pci variants (Yishai Hadas,
Max Gurtovoy, Jason Gunthorpe)
- Replace duplicated reflck with core support for managing first
open, last close, and device sets (Jason Gunthorpe, Max Gurtovoy,
Yishai Hadas)
- Fix non-modular mdev support and don't nag about request callback
support (Christoph Hellwig)
- Add semaphore to protect instruction intercept handler and replace
open-coded locks in vfio-ap driver (Tony Krowiak)
- Convert vfio-ap to vfio_register_group_dev() API (Jason Gunthorpe)
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Merge tag 'vfio-v5.15-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson:
- Fix dma-valid return WAITED implementation (Anthony Yznaga)
- SPDX license cleanups (Cai Huoqing)
- Split vfio-pci-core from vfio-pci and enhance PCI driver matching to
support future vendor provided vfio-pci variants (Yishai Hadas, Max
Gurtovoy, Jason Gunthorpe)
- Replace duplicated reflck with core support for managing first open,
last close, and device sets (Jason Gunthorpe, Max Gurtovoy, Yishai
Hadas)
- Fix non-modular mdev support and don't nag about request callback
support (Christoph Hellwig)
- Add semaphore to protect instruction intercept handler and replace
open-coded locks in vfio-ap driver (Tony Krowiak)
- Convert vfio-ap to vfio_register_group_dev() API (Jason Gunthorpe)
* tag 'vfio-v5.15-rc1' of git://github.com/awilliam/linux-vfio: (37 commits)
vfio/pci: Introduce vfio_pci_core.ko
vfio: Use kconfig if XX/endif blocks instead of repeating 'depends on'
vfio: Use select for eventfd
PCI / VFIO: Add 'override_only' support for VFIO PCI sub system
PCI: Add 'override_only' field to struct pci_device_id
vfio/pci: Move module parameters to vfio_pci.c
vfio/pci: Move igd initialization to vfio_pci.c
vfio/pci: Split the pci_driver code out of vfio_pci_core.c
vfio/pci: Include vfio header in vfio_pci_core.h
vfio/pci: Rename ops functions to fit core namings
vfio/pci: Rename vfio_pci_device to vfio_pci_core_device
vfio/pci: Rename vfio_pci_private.h to vfio_pci_core.h
vfio/pci: Rename vfio_pci.c to vfio_pci_core.c
vfio/ap_ops: Convert to use vfio_register_group_dev()
s390/vfio-ap: replace open coded locks for VFIO_GROUP_NOTIFY_SET_KVM notification
s390/vfio-ap: r/w lock for PQAP interception handler function pointer
vfio/type1: Fix vfio_find_dma_valid return
vfio-pci/zdev: Remove repeated verbose license text
vfio: platform: reset: Convert to SPDX identifier
vfio: Remove struct vfio_device_ops open/release
...
Now that vfio_pci has been split into two source modules, one focusing on
the "struct pci_driver" (vfio_pci.c) and a toolbox library of code
(vfio_pci_core.c), complete the split and move them into two different
kernel modules.
As before vfio_pci.ko continues to present the same interface under sysfs
and this change will have no functional impact.
Splitting into another module and adding exports allows creating new HW
specific VFIO PCI drivers that can implement device specific
functionality, such as VFIO migration interfaces or specialized device
requirements.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
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/20210826103912.128972-14-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
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>
Expose an 'override_only' helper macro (i.e.
PCI_DRIVER_OVERRIDE_DEVICE_VFIO) for VFIO PCI sub system and add the
required code to prefix its matching entries with "vfio_" in
modules.alias file.
It allows VFIO device drivers to include match entries in the
modules.alias file produced by kbuild that are not used for normal
driver autoprobing and module autoloading. Drivers using these match
entries can be connected to the PCI device manually, by userspace, using
the existing driver_override sysfs.
For example the resulting modules.alias may have:
alias pci:v000015B3d00001021sv*sd*bc*sc*i* mlx5_core
alias vfio_pci:v000015B3d00001021sv*sd*bc*sc*i* mlx5_vfio_pci
alias vfio_pci:v*d*sv*sd*bc*sc*i* vfio_pci
In this example mlx5_core and mlx5_vfio_pci match to the same PCI
device. The kernel will autoload and autobind to mlx5_core but the
kernel and udev mechanisms will ignore mlx5_vfio_pci.
When userspace wants to change a device to the VFIO subsystem it can
implement a generic algorithm:
1) Identify the sysfs path to the device:
/sys/devices/pci0000:00/0000:00:01.0/0000:01:00.0
2) Get the modalias string from the kernel:
$ cat /sys/bus/pci/devices/0000:01:00.0/modalias
pci:v000015B3d00001021sv000015B3sd00000001bc02sc00i00
3) Prefix it with vfio_:
vfio_pci:v000015B3d00001021sv000015B3sd00000001bc02sc00i00
4) Search modules.alias for the above string and select the entry that
has the fewest *'s:
alias vfio_pci:v000015B3d00001021sv*sd*bc*sc*i* mlx5_vfio_pci
5) modprobe the matched module name:
$ modprobe mlx5_vfio_pci
6) cat the matched module name to driver_override:
echo mlx5_vfio_pci > /sys/bus/pci/devices/0000:01:00.0/driver_override
7) unbind device from original module
echo 0000:01:00.0 > /sys/bus/pci/devices/0000:01:00.0/driver/unbind
8) probe PCI drivers (or explicitly bind to mlx5_vfio_pci)
echo 0000:01:00.0 > /sys/bus/pci/drivers_probe
The algorithm is independent of bus type. In future the other buses with
VFIO device drivers, like platform and ACPI, can use this algorithm as
well.
This patch is the infrastructure to provide the information in the
modules.alias to userspace. Convert the only VFIO pci_driver which results
in one new line in the modules.alias:
alias vfio_pci:v*d*sv*sd*bc*sc*i* vfio_pci
Later series introduce additional HW specific VFIO PCI drivers, such as
mlx5_vfio_pci.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> # for pci.h
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-11-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is a preparation before splitting vfio_pci.ko to 2 modules.
As module parameters are a kind of uAPI they need to stay on vfio_pci.ko
to avoid a user visible impact.
For now continue to keep the implementation of these options in
vfio_pci_core.c. Arguably they are vfio_pci functionality, but further
splitting of vfio_pci_core.c will be better done in another series
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-9-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
igd is related to the vfio_pci pci_driver implementation, move it out of
vfio_pci_core.c.
This is preparation for splitting vfio_pci.ko into 2 drivers.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-8-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Split the vfio_pci driver into two logical parts, the 'struct
pci_driver' (vfio_pci.c) which implements "Generic VFIO support for any
PCI device" and a library of code (vfio_pci_core.c) that helps
implementing a struct vfio_device on top of a PCI device.
vfio_pci.ko continues to present the same interface under sysfs and this
change should have no functional impact.
Following patches will turn vfio_pci and vfio_pci_core into a separate
module.
This is a preparation for allowing another module to provide the
pci_driver and allow that module to customize how VFIO is setup, inject
its own operations, and easily extend vendor specific functionality.
At this point the vfio_pci_core still contains a lot of vfio_pci
functionality mixed into it. Following patches will move more of the
large scale items out, but another cleanup series will be needed to get
everything.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
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/20210826103912.128972-7-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The vfio_device structure is embedded into the vfio_pci_core_device
structure, so there is no reason for not including the header file in
the vfio_pci_core header as well.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-6-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is another preparation patch for separating the vfio_pci driver to
a subsystem driver and a generic pci driver. This patch doesn't change
any logic.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-5-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is a preparation patch for separating the vfio_pci driver to a
subsystem driver and a generic pci driver. This patch doesn't change any
logic.
The new vfio_pci_core_device structure will be the main structure of the
core driver and later on vfio_pci_device structure will be the main
structure of the generic vfio_pci driver.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-4-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is a preparation patch for separating the vfio_pci driver to a
subsystem driver and a generic pci driver. This patch doesn't change any
logic.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-3-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This is a preparation patch for separating the vfio_pci driver to a
subsystem driver and a generic pci driver. This patch doesn't change any
logic.
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20210826103912.128972-2-yishaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio_find_dma_valid is defined to return WAITED on success if it was
necessary to wait. However, the loop forgets the WAITED value returned
by vfio_wait() and returns 0 in a later iteration. Fix it.
Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Reviewed-by: Steve Sistare <steven.sistare@oracle.com>
Link: https://lore.kernel.org/r/1629736550-2388-1-git-send-email-anthony.yznaga@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The SPDX and verbose license text are redundant, however in this case
the verbose license indicates a GPL v2 only while SPDX specifies v2+.
Remove the verbose license and correct SPDX to the more restricted
version.
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Link: https://lore.kernel.org/r/20210824003749.1039-1-caihuoqing@baidu.com
[aw: commit log]
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Like vfio_pci_dev_set_try_reset() this code wants to reset all of the
devices in the "reset group" which is the same membership as the device
set.
Instead of trying to reconstruct the device set from the PCI list go
directly from the device set's device list to execute the reset.
The same basic structure as vfio_pci_dev_set_try_reset() is used. The
'vfio_devices' struct is replaced with the device set linked list and we
simply sweep it multiple times under the lock.
This eliminates a memory allocation and get/put traffic and another
improperly locked test of pci_dev_driver().
Reviewed-off-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/10-v4-9ea22c5e6afb+1adf-vfio_reflck_jgg@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Jason Gunthorpe