By looking at Linux kernel boot time, we identified that a lot of time
was spent registering and unregistering IRQ fds to KVM. This is not
efficient and certainly not a wrong behavior from the Linux kernel,
but rather a problem with the Cloud-Hypervisor's implementation of
MSI-X.
The way to fix this issue is by ensuring the initial conditions are
correct, which means the entire MSI-X vector table must be disabled
and masked. Additionally, each vector must be individually masked.
With these correct conditions, Linux won't start masking interrupt
vectors, and later unmask them since they will be seen as masked from
the beginning. This means the OS will simply have to unmask them when
needed, avoiding the extra operation.
Another aspect of this patch is to prevent Cloud-Hypervisor from
enabling (by registering IRQ fd) all vectors when either the global
'mask' or 'enable' bits are set. Instead, we can simply let the mask()
and unmask() operations take care of it if needed.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Misspellings were identified by https://github.com/marketplace/actions/check-spelling
* Initial corrections suggested by Google Sheets
* Additional corrections by Google Chrome auto-suggest
* Some manual corrections
Signed-off-by: Josh Soref <jsoref@users.noreply.github.com>
This removes the dependency of the pci crate on the devices crate which
now only contains the device implementations themselves.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
There will be some cases where the implementation of the snapshot()
function from the Snapshottable trait will require to modify some
internal data, therefore we make this possible by updating the trait
definition with snapshot(&mut self).
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This simplies some of the handling for PCI BARs particularly with
respect to snapshot and restore. No attempt has been made to handle the
64-bit bar handling in a different manner to that which was used before.
Fixes: #1153
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
In this commit we saved the BDF of a PCI device and set it to "devid"
in GSI routing entry, because this field is mandatory for GICv3-ITS.
Signed-off-by: Michael Zhao <michael.zhao@arm.com>
The type is now hypervisor::Vm. Switch from KVM specific name vm_fd to a
generic name just like 8186a8eee6 ("vmm: interrupt: Rename vm_fd").
No functional change.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
Start moving the vmm, arch and pci crates to being hypervisor agnostic
by using the hypervisor trait and abstractions. This is not a complete
switch and there are still some remaining KVM dependencies.
Signed-off-by: Muminul Islam <muislam@microsoft.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Currently, not every feature of the cloud-hypervisor is enabled
on AArch64, which means that on AArch64 machines, the
`run_unit_tests.sh` needs to be tailored and some unit test cases
should be run on x86_64 only.
Also this commit fixes the typo and unifies `Arm64` and `AArch64`
in the AArch64 document.
Signed-off-by: Henry Wang <Henry.Wang@arm.com>
cloud-hypervisor: 763.978581807s: ERROR:pci/src/vfio.rs:651 -- failed to remove all guest memory regions from iommu table
when poweroff a vm with vfio device, clh will finally remove all guest memory region from iommu table
with the method unset_dma_map, not method setup_dma_map.
Signed-off-by: LiYa'nan <oliverliyn@gmail.com>
There is a much stronger PCI dependency from vfio_pci.rs than a VFIO one
from pci/src/vfio.rs. It seems more natural to have the PCI specific
VFIO implementation in the PCI crate rather than the other way around.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
In order to let the PciBus user choose where a device should be placed
on the bus, a new function get_device_id() is introduced. This will be
helpful in the context of snapshot/restore as the caller will be able to
place the PCI devices on the same slot they were placed before the
snapshot was taken.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The PCI configuration from each PCI device is modified at runtime as we
can expect the guest OS to write to some PCI capability structure, or
move the BAR to a different location in the guest address space.
For all the reasons why such configuration might differ from the initial
configuration, we must store the registers values to be able to restore
them with the right values whenever a PCI device is being restored.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to restore devices relying on MSI-X, the MsixConfig structure
must be restored with the correct values. Additionally, the KVM routes
must be restored so that interrupts can be delivered through KVM the way
they were configured before the snapshot was taken.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
When reporting the BAR size it is necessary to return a value that is
encoded such that all the bits are set that represent the mask of the
natural alignment of the field.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Add support for specifying the PCI revision in the PCI configuration and
populate this with the value of 1 for virtio-pci devices.
The virtio-pci specification is slightly ambiguous only saying that
transitional (i.e. devices that support legacy and virtio 1.0) should
set this to 0. In practice it seems that software expects the revision
to be set to 1 for modern only devices.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
By using a Vec to hold the list of devices on the PciBus, there's a
problem when we use unplug. Indeed, the vector of devices gets reduced
and if the unplugged device was not the last one from the list, every
other device after this one is shifted on the bus.
To solve this problem, a HashMap is used. This allows to keep track of
the exact place where each device stands on the bus.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The point of this new method is to let the caller decide when the
implementation of the PciDevice should free the BARs previously
allocated through the other method allocate_bars().
This provides a way to perform proper cleanup for any PCI device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Upon removal of a PCI device, make sure we don't hold onto the device ID
as it could be reused for another device later.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to handle the case where devices are very often plugged and
unplugged from a VM, we need to handle the PCI device ID allocation
better.
Any PCI device could be removed, which means we cannot simply rely on
the vector size to give the next available PCI device ID.
That's why this patch stores in memory the information about the 32
slots availability. Based on this information, whenever a new slot is
needed, the code can correctly provide an available ID, or simply return
an error because all slots are taken.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Simple function relying on the retain() method from std::Vec, allowing
to remove every occurence of the same device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that the BusDevice devices are stored as Weak references by the IO
and MMIO buses, there's no need to use Weak references from the PciBus
anymore.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
We want to prevent from losing interrupts while they are masked. The
way they can be lost is due to the internals of how they are connected
through KVM. An eventfd is registered to a specific GSI, and then a
route is associated with this same GSI.
The current code adds/removes a route whenever a mask/unmask action
happens. Problem with this approach, KVM will consume the eventfd but
it won't be able to find an associated route and eventually it won't
be able to deliver the interrupt.
That's why this patch introduces a different way of masking/unmasking
the interrupts, simply by registering/unregistering the eventfd with the
GSI. This way, when the vector is masked, the eventfd is going to be
written but nothing will happen because KVM won't consume the event.
Whenever the unmask happens, the eventfd will be registered with a
specific GSI, and if there's some pending events, KVM will trigger them,
based on the route associated with the GSI.
Suggested-by: Liu Jiang <gerry@linux.alibaba.com>
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
We should not assume the offset produced by ECAM is identical to the
CONFIG_ADDRESS register of legacy PCI port io enumeration.
Signed-off-by: Qiu Wenbo <qiuwenbo@phytium.com.cn>
In order to anticipate the need to support more features related to the
access of a device's PCI config space, this commits changes the self
reference in the function read_config_register() to be mutable.
This also brings some more flexibility for any implementation of the
PciDevice trait.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Both InterruptDelivery and InterruptParameters can be removed from the
pci crate as they are not used anymore.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
There's no need for assign_irq() or assign_msix() functions from the
PciDevice trait, as we can see it's never used anywhere in the codebase.
That's why it's better to remove these methods from the trait, and
slightly adapt the existing code.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that KVM specific interrupts are handled through InterruptManager
trait implementation, the pci crate does not need to rely on kvm_ioctls
and kvm_bindings crates.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Based on all the previous changes, we can at this point replace the
entire interrupt management with the implementation of InterruptManager
and InterruptSourceGroup traits.
By using KvmInterruptManager from the DeviceManager, we can provide both
VirtioPciDevice and VfioPciDevice a way to pick the kind of
InterruptSourceGroup they want to create. Because they choose the type
of interrupt to be MSI/MSI-X, they will be given a MsiInterruptGroup.
Both MsixConfig and MsiConfig are responsible for the update of the GSI
routes, which is why, by passing the MsiInterruptGroup to them, they can
still perform the GSI route management without knowing implementation
details. That's where the InterruptSourceGroup is powerful, as it
provides a generic way to manage interrupt, no matter the type of
interrupt and no matter which hypervisor might be in use.
Once the full replacement has been achieved, both SystemAllocator and
KVM specific dependencies can be removed.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Callbacks are not the most Rust idiomatic way of programming. The right
way is to use a Trait to provide multiple implementation of the same
interface.
Additionally, a Trait will allow for multiple functions to be defined
while using callbacks means that a new callback must be introduced for
each new function we want to add.
For these two reasons, the current commit modifies the existing
VirtioInterrupt callback into a Trait of the same name.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
At this point, both MSI and MSI-X handle the KVM GSI routing update,
which means the vfio crate does not have to deal with it anymore.
Therefore, several functions can be removed from the vfio-pci code, as
they are not needed anymore.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that MsiConfig has access to both KVM VmFd and the list of GSI
routes, the update of the KVM GSI routes can be directly done from
MsiConfig instead of specifically from the vfio-pci implementation.
By moving the KVM GSI routes update at the MsiConfig level, any PCI
device such as vfio-pci, virtio-pci, or any other emulated PCI device
can benefit from it, without having to implement it on their own.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The same way we have MsixConfig in charge of managing whatever relates
to MSI-X vectors, we need a MsiConfig structure to manage MSI vectors.
The MsiCap structure is still needed as a low level API, but it is now
part of the MsiConfig which oversees anything related to MSI.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In order to factorize one step further, we let MsixConfig perform the
interrupt enabling/disabling. This is done by registering/unregistering
the KVM irq_fds of all GSI routes related to this device.
And now that MsixConfig is in charge of the irq_fds, vfio-pci must rely
on it to retrieve them and provide them to the vfio driver.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that MsixConfig has access to the irq_fd descriptors associated with
each vector, it can directly write to it anytime it needs to trigger an
interrupt.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that MsixConfig has access to both KVM VmFd and the list of GSI
routes, the update of the KVM GSI routes can be directly done from
MsixConfig instead of specifically from the vfio-pci implementation.
By moving the KVM GSI routes update at the MsixConfig level, both
vfio-pci and virtio-pci (or any other emulated PCI device) can benefit
from it, without having to implement it on their own.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Because MsixConfig will be responsible for updating KVM GSI routes at
some point, it is necessary that it can access the list of routes
contained by gsi_msi_routes.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Because MsixConfig will be responsible for updating the KVM GSI routes
at some point, it must have access to the VmFd to invoke the KVM ioctl
KVM_SET_GSI_ROUTING.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The point here is to let MsixConfig take care of the GSI allocation,
which means the SystemAllocator must be passed from the vmm crate all
the way down to the pci crate.
Once this is done, the GSI allocation and irq_fd creation is performed
by MsixConfig directly.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>