From a VirtioPciDevice perspective, there are two types of BARs, either
the virtio configuration BAR or the SHaredMemory BAR.
The SHaredMemory BAR address comes from the virtio device directly as
the memory region had been previously allocated when the virtio device
has been created. So for this BAR, there's nothing to do when restoring
a VM, since the associated virtio device is already restored with the
appropriate resources, hence the BAR will already be at the right
address.
The remaining configuration BAR is different, as we usually get its
address from the SystemAllocator. This means in case we restore a VM,
we must provide this value, bypassing the allocator. This is what this
commit takes care of, by letting the caller set the base address for the
configuration BAR prior to allocating the BARs.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This gives Cloud-Hypervisor the possibility to snapshot and restore a
VM running with virtio-pci devices attached to it.
The VirtioPciDevice snapshot contains a vector of sub-snapshots to store
and restore information related to MsixConfig, VirtioPciCommonConfig and
PciConfiguration structures, along with snapshot data related to
VirtioPciDevice itself.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This structure contains all the virtio generic information, and as part
of restoring a VM with virtio-pci devices, it is important to restore
these values to ensure the device's proper functioning.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Upon a virtio reset, the driver expects that available and used indexes
will be reset to 0. That's why we need to reset these values from the
VMM for any virtio device that might get reset.
This issue was not detected before because the Vec<Queue> maintained
through VirtioPciDevice or MmioDevice was never updated from the virtio
device thread after the device had been actived. For this reason, upon
reset, both available and used indexes were already at the value 0.
The issue arose when trying to reset a device after the VM was restored.
That's because during the restore, each queue is assigned with the right
available and used indexes before it is passed to the device through the
activate function. And that's why upon reset, each queue was still
assigned with these indexes while it should have been reset to 0.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
All our virtio devices support to be reset, but the virtio-mmio
transport layer was not implemented for it. This patch fixes this
lack of support.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
It's not possible to call UnixListener::Bind() on an existing file so
unlink the created socket when shutting down the Vsock device.
This will allow the VM to be rebooted with a vsock device.
Fixes: #1083
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
It is based off the name from the virtio device attached to this
transport layer.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
It is based off the name from the virtio device attached to this
transport layer.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This identifier is chosen from the DeviceManager so that it will manage
all identifiers across the VM, which will ensure uniqueness.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that all virtio devices are assigned with identifiers, they could
all be removed from the VM. This is not something that we want to allow
because it does not make sense for some devices. That's why based on the
device type, we remove the device or we return an error to the user.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
FS_IO is part of the actions a vhost-user-fs daemon can ask the VMM to
perform on its behalf. It is meant to read/write the content from a file
descriptor directly into a guest memory region. This region can either
be a RAM region or the dedicated cache region for virtio-fs.
The way FS_IO was implemented, it was only expecting the guest physical
address provided through the "cache_offset" field to refer to the cache
region. Unfortunately, this was only implementing FS_IO partially.
This patch extends the existing FS_IO implementation by checking the GPA
against the cache region as a first step, but if it is not part of the
cache region address range, then we fallback onto searching for a RAM
region that could match. If there is a matching RAM region, we retrieve
the corresponding host address to let the VMM read/write from/to it.
Fixes: #1054
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Jose Carlos Venegas Munoz <jose.carlos.venegas.munoz@intel.com>
This patch implements the Snapshottable trait for virtio-console, which
enables migration support for it. A VM with a virtio-console device
attached can be snapshot and then restored without issues.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
This brings the migration support to virtio-pmem device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
The frame buffer must be updated depending on the amount read from it,
which depends on the number and depth of descriptors available at the
time of the processing.
This patch handles this buffer update, and allow for large buffers to be
correctly processed in multiple rounds.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
On the restore path, using the available and used indexes read from
memory to fill the Queue structure was a mistake. Indeed, the available
index is written from the guest and it reflects the last available index
in the descriptor table. But the driver might have queued a lot of
buffers which have not yet been used by the device. This leads to a
situation where the next_avail from Queue is completely different from
the one we can read from memory.
Instead, the right way to determine the next_avail index that should be
used by the device is by relying on the used index from the memory. This
index represents the correct information we're looking for as it has
been updated before the snapshot to let the guest know the next index to
process.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
First, this modifies the existing helpers on how to get indexes for
available and used rings from memory. Instead of updating the queue
through each helper, they are now used as simple getters.
Based on these new getters, we could create a new helper to determine if
the queue has some available descriptors already queued from the driver
side. This helper is going to be particularly helpful when trying to
determine from a virtio thread if a queue is already loaded with some
available buffers that can be used to send information to the guest.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Since the virtio-fs device is backed by a vhost-user process, it is
important to implement the proper shutdown() function from the
VirtioDevice trait, as vhost-user-blk and vhost-user-net do.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
When hot-unplugging the virtio-pmem from the VM, we don't remove the
associated userspace mapping. This patch will let us fix this in a
following patch. For now, it simply adapts the code so that the Pmem
device knows about the mapping associated with it. By knowing about it,
it can expose it to the caller through the new userspace_mappings()
function.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This will help when we will implement the hot-unplug of the virtio-fs
device, as we will have to remove correctly the userspace mappings
associated with the device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Introduce new getter function to the VirtioDevice trait, as it will
allow the caller to retrieve the list of userspace mappings associated
with the device.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In the context of the shared memory region used by virtio-fs in order to
support DAX feature, the shared region is exposed as a dedicated PCI
BAR, and it is backed by a KVM userspace mapping.
Upon BAR remapping, the BAR is moved to a different location in the
guest address space, and the KVM mapping must be updated accordingly.
Additionally, we need the VirtioDevice to report the updated guest
address through the shared memory region returned by get_shm_regions().
That's why a new setter is added to the VirtioDevice trait, so that
after the mapping has been updated for KVM, we can tell the VirtioDevice
the new guest address the shared region is located at.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
By adding the shared memory regions to the list of BARs, we make sure
the DeviceManager will register it as a BAR on the PCI bus. Without
this, when PCI BAR reprogramming happens, the PCI bus errors since it
does not know about any BAR at the specified address.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Any virtio device relying on the mmio transport layer can be snapshotted
and restored thanks to this new patch. From the MmioDevice perspective,
it is mainly a matter of saving the information about the virtqueues as
the restore path will need them to activate the device (if needed
because it has been activated before being snapshotted).
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
In anticipation for adding snapshot/restore support to virtio devices,
this commit introduces two new helpers updating the available and used
indexes of a queue, relying on the guest memory.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This commit relies on serde to serialize and deserialize the content of
a Queue structure. This will be useful information to store when
implementing snapshot/restore feature for virtio devices.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.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>
Add an accessor to return the underlying VirtioDevice. This is useful
for managing the removal of the device from internal datastructures when
handling virtio-pci device unplug.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
In order to support freeing the memory that is allocated we need to make
sure that we update the internal representation so that free_bars() can
correctly free the memory if the device has its BARs moved.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Implement the free_bars() method from the PciDevice trait which is used
as part of the device removal process. Although there is only one BAR
allocated by VirtioPciDevice simplify the code by using a vector.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Move the release of the managed memory region from the DeviceManager to
the vhost-user-fs device. This ensures that the memory will be freed when
the device is unplugged which will lead to it being Drop()ed.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Move the release of the managed memory region from the DeviceManager to
the virtio-pmem device. This ensures that the memory will be freed when
the device is unplugged which will lead to it being Drop()ed.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
A Snapshottable component can snapshot itself and
provide a MigrationSnapshot payload as a result.
A MigrationSnapshot payload is a map of component IDs to a list of
migration sections (MigrationSection). As component can be made of
several Migratable sub-components (e.g. the DeviceManager and its
device objects), a migration snapshot can be made of multiple snapshot
itself.
A snapshot is a list of migration sections, each section being a
component state snapshot. Having multiple sections allows for easier and
backward compatible migration payload extensions.
Once created, a migratable component snapshot may be transported and this
is what the Transportable trait defines, through 2 methods: send and recv.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Signed-off-by: Yi Sun <yi.y.sun@linux.intel.com>
Return libc::EINVAL instead of custom "Wrong offset" error, as mmap(2)
returns EINVAL when offset/len is invalid.
Signed-off-by: Eryu Guan <eguan@linux.alibaba.com>
In fs_slave_map/unmap/sync, we only made sure offset < cache_size, but
didn't validate (offset + len). We should ensure [offset, offset+len]
is within cache range as well.
Signed-off-by: Eryu Guan <eguan@linux.alibaba.com>
