With some of the factorization that happened to be able to support VFIO
hotplug, one mistake was made. In case a vIOMMU is created through a
virtio-iommu device, and no matter the "iommu" option value from the
VFIO device parameter, the VFIO device was always placed behind the
virtual IOMMU.
This commit fixes this wrong behavior by making sure the device
configuration is taken into account to decide if it should be attached
or not to the virtual IOMMU.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Add a new id option to the VFIO hotplug command so that it matches the
VFIO coldplug semantic.
This is done by refactoring the existing code for VFIO hotplug, where
VmAddDeviceData structure is replaced by DeviceConfig. This structure is
the one used whenever a VFIO device is coldplugged, which is why it
makes sense to reuse it for the hotplug codepath.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Add the ability to specify the "id" associated with a device, by adding
an extra option to the parameter --device.
This new option is not mandatory, and by default, the VMM will take care
of finding a unique identifier.
If the identifier provided by the user through this new option is not
unique, an error will be thrown and the VM won't be started.
Fixes#881
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The 32 bits MMIO address space is handled separately from the 64 bits
one. For this reason, we need to invoke the appropriate freeing function
to remove a range from this address space.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that PciDevice trait has a dedicated function to remove the bars,
the DeviceManager can invoke this function whenever a PCI device is
unplugged from the VM.
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>
This commit ensures that when a VFIO device is hot-unplugged from the
VM, it is also removed from the VmConfig. This prevents a potential
reboot from creating the device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Add a new field to the DeviceConfig, allowing the VMM to allocate a name
to the VFIO devices.
By identifying a VFIO device with a unique name, we can make sure a user
can properly unplug it at any time.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This commit introduces the new command "remove-device" that will let a
user hot-unplug a VFIO PCI device from an already running VM.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This commit implements the eject function so that a VFIO device will be
removed from any bus it might sit on, and from any list it might be
stored in.
The idea is to reach a point where there is no reference of the device
anywhere in the code, so that the Drop implementation will be invoked
and so that the device will be fully removed from the VMM.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
When the guest OS is done removing a PCI device, it will invoke the _EJ0
method from ACPI, associated with the device. This will trigger a port
IO write to a region known by the VMM. Upon this writing, the VMM will
trap the VM exit and retrieve the written value.
Based on the value, the VMM will invoke its eject_device() method to
finalize the removal of the device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
As we try to keep track of every PCI device related to the VM, we don't
want to have separate lists depending on the concrete type associated
with the PciDevice trait. Also, we want to be able to cast the actual
type into any trait or concrete type.
The most efficient way to solve all these issues is to store every
device as an Arc<dyn Any + Send + Sync>. This gives the ability to
downcast into the appropriate concrete type, and then to cast back into
any trait that we might need.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Add a new list storing the device names across the entire codebase. VFIO
devices are added to the list whenever a new one is created. By default,
each VFIO device is given a name "vfioX" where X is the first available
integer.
Along with this new list of names, another list is created, grouping PCI
device's name with its associated b/d/f. This will be useful to keep
track of the created devices so that we can implement unplug
functionality.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The Vm structure was used to store a strong reference to the IO bus.
This is not needed anymore since the AddressManager is logically the
one holding this strong reference. This has been made possible by the
introduction of Weak references on the Bus structure itself.
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
DeviceManager anymore.
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
CpuManager anymore.
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>
The point is to make sure the DeviceManager holds a strong reference of
each BusDevice inserted on the IO and MMIO buses. This will allow these
buses to hold Weak references onto the BusDevice devices.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The method add_vfio_device() from the DeviceManager needs to be mutable
if we want later to be able to update some internal fields from the
DeviceManager from this same function.
This commit simply takes care of making the necessary changes to change
this function as mutable.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
It's more logical to name the field referring to the DeviceManager as
"device_manager" instead of "devices".
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
By inserting the DeviceManager on the IO bus, we introduced some cyclic
dependency:
DeviceManager ---> AddressManager ---> Bus ---> BusDevice
^ |
| |
+---------------------------------------------+
This cycle needs to be broken by inserting a Weak reference instead of
an Arc (considered as a strong reference).
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Ensures the configuration is updated after a new device has been
hotplugged. In the event of a reboot, this means the new VM will be
started with the new device that had been previously hotplugged.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This commit finalizes the VFIO PCI hotplug support, based on all the
previous commits preparing for it.
One thing to notice, this does not support vIOMMU yet. This means we can
hotplug VFIO PCI devices, but we cannot attach them to an existing or a
new virtio-iommu device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This factorization is very important as it will allow both the standard
codepath and the VFIO PCI hotplug codepath to rely on the same function
to perform the addition of a new VFIO PCI device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Whenever the user wants to hotplug a new VFIO PCI device, the VMM will
have to trigger a hotplug notification through the GED device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This commit introduces the new command "add-device" that will let a user
hotplug a VFIO PCI device to an already running VM.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Through the BusDevice implementation from the DeviceManager, and by
inserting the DeviceManager on the IO bus for a specific IO port range,
the VMM now has the ability to handle PCI device hotplug.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In anticipation of inserting the DeviceManager on the IO/MMIO buses,
the DeviceManager must implement the BusDevice trait.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Create a small method that will perform both hotplug of all the devices
identified by PCIU bitmap, and then perform the hotunplug of all the
devices identified by the PCID bitmap.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The _EJ0 method provides the guest OS a way to notify the VMM that the
device has been properly ejected from the guest OS. Only after this
point, the VMM can fully remove the device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This new PHPR device in the DSDT table introduces some specific
operation regions and the associated fields.
PCIU stands for "PCI up", which identifies PCI devices that must be
added.
PCID stands for "PCI down", which identifies PCI devices that must be
removed.
B0EJ stands for "Bus 0 eject", which identifies which device on the bus
has been ejected by the guest OS.
Thanks to these fields, the VMM and the guest OS can communicate while
performing hotplug/hotunplug operations.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Adds the DVNT method to the PCI0 device in the DSDT table. This new
method is responsible for checking each slot and notify the guest OS if
one of the slots is supposed to be added or removed.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This commit introduces the ACPI support for describing the 32 device
slots attached to the main PCI host bridge.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In anticipation of the support for device hotplug, this commit moves the
DeviceManager object into an Arc<Mutex<>> when the DeviceManager is
being created. The reason is, we need the DeviceManager to implement the
BusDevice trait and then provide it to the IO bus, so that IO accesses
related to device hotplug can be handled correctly.
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>
Recently, vhost_user_block gained the ability of actively polling the
queue, a feature that can be disabled with the poll_queue property.
This change adds this property to DiskConfig, so it can be used
through the "disk" argument.
For the moment, it can only be used when vhost_user=true, but this
will change once virtio-block gets the poll_queue feature too.
Fixes: #787
Signed-off-by: Sergio Lopez <slp@redhat.com>
