This change is important to do a proper resource cleanup. We decided
to do this repetitive approach as VirtioCommon can't implement Drop
without major changes to the corresponding code. Also, devices such as
Net can't easily use the epoll_threads-abstraction from VirtioCommon as
it has multiple threads with different semantics.
Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
The information about the identifier related to a Snapshot is only
relevant from the BTreeMap perspective, which is why we can get rid of
the duplicated identifier in every Snapshot structure.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Following the new restore design, it is not appropriate to set every
virtio device threads into a paused state after they've been started.
This is why we remove the line of code pausing the devices only after
they've been restored, and replace it with a small patch in every virtio
device implementation. When a virtio device is created as part of a
restored VM, the associated "paused" boolean is set to true. This
ensures the corresponding thread will be directly parked when being
started, avoiding the thread to be in a different state than the one it
was on the source VM during the snapshot.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Since the processing of the console inputs was moved from the VMM thread
to the virtio-console thread (#3061), we have been using the 'FILE_EVENT'
to handle input from stdin/pty/file, which made 'INPUT_EVENT' obsoleted.
Signed-off-by: Bo Chen <chen.bo@intel.com>
Following the new design proposal to improve the restore codepath when
migrating a VM, all virtio devices are supplied with an optional state
they can use to restore from. The restore() implementation every device
was providing has been removed in order to prevent from going through
the restoration twice.
Here is the list of devices now following the new restore design:
- Block (virtio-block)
- Net (virtio-net)
- Rng (virtio-rng)
- Fs (vhost-user-fs)
- Blk (vhost-user-block)
- Net (vhost-user-net)
- Pmem (virtio-pmem)
- Vsock (virtio-vsock)
- Mem (virtio-mem)
- Balloon (virtio-balloon)
- Watchdog (virtio-watchdog)
- Vdpa (vDPA)
- Console (virtio-console)
- Iommu (virtio-iommu)
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The the number of queues and associated events is known and fixed. We
can define and use each of them explicitly and avoid using vector (and
hence direct indexing), which is cleaner and slightly more efficient.
Signed-off-by: Bo Chen <chen.bo@intel.com>
Through multiple changes, this patch aims at providing a reliable
solution for detecting the state of the PTY's connection. Being able to
find out when the other end of the PTY is connected is essential to
prevent the loss of data being output through the PTY. When the PTY
isn't connected, the output is buffered through the SerialBuffer, the
same solution that was created for the serial port initially.
Fixes#4521
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Now that we rely on pop_descriptor_chain() rather than iter() to iterate
over a queue, there's no more borrow on the queue itself, meaning we can
invoke add_used() directly for the iteration loop. This simplifies the
processing of the queues for each virtio device, and bring some possible
performance improvement given we don't have to iterate twice over the
list of descriptors to invoke add_used().
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Using pop_descriptor_chain() is much more appropriate than iter() since
it recreates the iterator every time, avoiding the queue to be borrowed
and allowing the virtio-net implementation to match all the other ones.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
The new virtio-queue version introduced some breaking changes which need
to be addressed so that Cloud Hypervisor can still work with this
version.
The most important change is about removing a handle to the guest memory
from the Queue, meaning the caller has to provide the guest memory
handle for multiple methods from the QueueT trait.
One interesting aspect is that QueueT has been widely extended to
provide every getter and setter we need to access and update the Queue
structure without having direct access to its internal fields.
This patch ports all the virtio and vhost-user devices to this new crate
definition. It also updates both vhost-user-block and vhost-user-net
backends based on the updated vhost-user-backend crate. It also updates
the fuzz directory.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Instead of passing separately a list of Queues and the equivalent list
of EventFds, we consolidate these two through a tuple along with the
queue index.
The queue index can be very useful if looking for the actual index
related to the queue, no matter if other queues have been enabled or
not.
It's also convenient to have the EventFd associated with the Queue so
that we don't have to carry two lists with the same amount of items.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Renaming translate() to translate_gva() to clarify we want to translate
a GVA address into a GPA.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
This new trait simplifies the address translation of a GuestAddress by
having GuestAddress implementing it.
The three crates virtio-devices, block_util and net_util have been
updated accordingly to rely on this new trait, helping with code
readability and limiting the amount of duplicated code.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Moving the whole codebase to rely on the AccessPlatform definition from
vm-virtio so that we can fully remove it from virtio-queue crate.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Since we're trying to move away from the translation happening in the
virtio-queue crate, the device itself is performing the address
translation when needed.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Instead of relying on the virtio-queue crate to store the information
about the MSI-X vectors for each queue, we handle this directly from the
PCI transport layer.
This is the first step in getting closer to the upstream version of
virtio-queue so that we can eventually move fully to the upstream
version.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Relying on the vm-virtio/virtio-queue crate from rust-vmm which has been
copied inside the Cloud Hypervisor tree, the entire codebase is moved to
the new definition of a Queue and other related structures.
The reason for this move is to follow the upstream until we get some
agreement for the patches that we need on top of that to make it
properly work with Cloud Hypervisor.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
When a pty is resized (using the TIOCSWINSZ ioctl -- see ioctl_tty(2)),
the kernel will send a SIGWINCH signal to the pty's foreground process
group to notify it of the resize. This is the only way to be notified
by the kernel of a pty resize.
We can't just make the cloud-hypervisor process's process group the
foreground process group though, because a process can only set the
foreground process group of its controlling terminal, and
cloud-hypervisor's controlling terminal will often be the terminal the
user is running it in. To work around this, we fork a subprocess in a
new process group, and set its process group to be the foreground
process group of the pty. The subprocess additionally must be running
in a new session so that it can have a different controlling
terminal. This subprocess writes a byte to a pipe every time the pty
is resized, and the virtio-console device can listen for this in its
epoll loop.
Alternatives I considered were to have the subprocess just send
SIGWINCH to its parent, and to use an eventfd instead of a pipe.
I decided against the signal approach because re-purposing a signal
that has a very specific meaning (even if this use was only slightly
different to its normal meaning) felt unclean, and because it would
have required using pidfds to avoid race conditions if
cloud-hypervisor had terminated, which added complexity. I decided
against using an eventfd because using a pipe instead allows the child
to be notified (via poll(2)) when nothing is reading from the pipe any
more, meaning it can be reliably notified of parent death and
terminate itself immediately.
I used clone3(2) instead of fork(2) because without
CLONE_CLEAR_SIGHAND the subprocess would inherit signal-hook's signal
handlers, and there's no other straightforward way to restore all signal
handlers to their defaults in the child process. The only way to do
it would be to iterate through all possible signals, or maintain a
global list of monitored signals ourselves (vmm:vm::HANDLED_SIGNALS is
insufficient because it doesn't take into account e.g. the SIGSYS
signal handler that catches seccomp violations).
Signed-off-by: Alyssa Ross <hi@alyssa.is>
This prepares us to be able to handle console resizes in the console
device's epoll loop, which we'll have to do if the output is a pty,
since we won't get SIGWINCH from it.
Signed-off-by: Alyssa Ross <hi@alyssa.is>
Introduce a common solution for spawning the virtio threads which will
make it easier to add the panic handling.
During this effort I discovered that there were no seccomp filters
registered for the vhost-user-net thread nor the vhost-user-block
thread. This change also incorporates basic seccomp filters for those as
part of the refactoring.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Move the processing of the input from stdin, PTY or file from the VMM
thread to the existing virtio-console thread. The handling of the resize
of a virtio-console has not changed but the name of the struct used to
support that has been renamed to reflect its usage.
Fixes: #3060
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
We are relying on applying empty 'seccomp' filters to support the
'--seccomp false' option, which will be treated as an error with the
updated 'seccompiler' crate. This patch fixes this issue by explicitly
checking whether the 'seccomp' filter is empty before applying the
filter.
Signed-off-by: Bo Chen <chen.bo@intel.com>
As the first step to complete live-migration with tracking dirty-pages
written by the VMM, this commit patches the dependent vm-memory crate to
the upstream version with the dirty-page-tracking capability. Most
changes are due to the updated `GuestMemoryMmap`, `GuestRegionMmap`, and
`MmapRegion` structs which are taking an additional generic type
parameter to specify what 'bitmap backend' is used.
The above changes should be transparent to the rest of the code base,
e.g. all unit/integration tests should pass without additional changes.
Signed-off-by: Bo Chen <chen.bo@intel.com>
Add a helper to VirtioCommon which returns duplicates of the EventFds
for kill and pause event.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
In order to support using Versionize for state structures it is necessary
to use simpler, primitive, data types in the state definitions used for
snapshot restore.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
With current serde_derive it is possible to #[derive(Serialize)] on
packed structures if they implement Copy. This allows the removal of the
manual equivalent code.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Simplify snapshot & restore code by using generics to specify helper
functions that take / make a Serialize / Deserialize struct
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
error: name `TYPE_UNKNOWN` contains a capitalized acronym
--> vm-virtio/src/lib.rs:48:5
|
48 | TYPE_UNKNOWN = 0xFF,
| ^^^^^^^^^^^^ help: consider making the acronym lowercase, except the initial letter: `Type_Unknown`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#upper_case_acronyms
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
If the function can never return an error this is now a clippy failure:
error: this function's return value is unnecessarily wrapped by `Result`
--> virtio-devices/src/watchdog.rs:215:5
|
215 | / fn set_state(&mut self, state: &WatchdogState) -> io::Result<()> {
216 | | self.common.avail_features = state.avail_features;
217 | | self.common.acked_features = state.acked_features;
218 | | // When restoring enable the watchdog if it was previously enabled. We reset the timer
... |
223 | | Ok(())
224 | | }
| |_____^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#unnecessary_wraps
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Even though the driver can provide fewer queues than those advertised
for some device types their is a minimum number that is required for
operation.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Rather than having to give and return the ioeventfd used for a device
clone them each time. This will make it simpler when we start handling
the driver enabling fewer queues than advertised by the device.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
In order to make the thread naming more useful derive their name from
the device id (which can be supplied by the user) and a device specific
suffix that has details of the individual queue (or queue pair.)
e.g.
rob@artemis:~$ pstree -p -c -l -t `pidof cloud-hypervisor`
cloud-hyperviso(27501)─┬─{_console}(27525)
├─{_disk0_q0}(27529)
├─{_disk0_q1}(27532)
├─{_net1_ctrl}(27533)
├─{_net1_qp0}(27534)
├─{_net1_qp1}(27535)
├─{_rng}(27526)
├─{http-server}(27504)
├─{seccomp_signal_}(27502)
├─{signal_handler}(27523)
├─{vcpu0}(27520)
├─{vcpu1}(27522)
└─{vmm}(27503)
Fixes: #2077
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
When a total ordering between multiple atomic variables is not required
then use Ordering::Acquire with atomic loads and Ordering::Release with
atomic stores.
This will improve performance as this does not require a memory fence
on x86_64 which Ordering::SeqCst will use.
Add a comment to the code in the vCPU handling code where it operates on
multiple atomics to explain why Ordering::SeqCst is required.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
In order to simplify the transition to VirtioCommon and to avoid needing
to set empty fields derive Default for VirtioCommon.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
