Following vhost-user specification, replace
all uses of master/slave with backend/frontend
in the vhost crate.
Signed-off-by: Albert Esteve <aesteve@redhat.com>
`extract_request_body()` assumes these types are POD as a safety
invariant, which is only possible if `VhostUserMsgValidator` is itself
an `unsafe trait` or depends on an `unsafe trait` with the correct
invariants.
`VhostUserMemoryRegion` is the only type that implemented
`VhostUserMsgValidator` and did not yet implement `ByteValued`
Signed-off-by: Manish Goregaokar <manishsmail@gmail.com>
Commit 8a4ba9d ("vhost-user-backend: fetch 'used' index from guest")
fixes an issue introduced in v0.10.0 that affects all vhost-user
backends like virtiofsd [1] or rust-vmm's vhost-device.
I easily reproduced the problem with vhost-device-vsock as well:
just restart the guest kernel and the device no longer works.
[1] https://gitlab.com/virtio-fs/virtiofsd/-/issues/120
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
commit 958cdec2b8 stopped GET_VRING_BASE
from resetting the vring. This was required because when the VM is
stopped/resumed the index will be 0 instead of the correct value.
However, after the guest driver changes, for instance, after reboot,
the 'used' index should be reset to 0. The bug fixed in that commit had
the unintended side effect of setting the 'used' index to 0 after a
driver change.
QEMU's vhost-user library sets the 'used' index when receiving
SET_VRING_ADDR, _probably_ to make sure that the VQ is configured.
Perhaps the appropriate place is when receiving the first kick.
A better solution would be to send the 'used' index in SET_VRING_BASE,
as is done when using packed VQs.
To keep compatibility with QEMU and just in case, any implementation
expects the 'used' index to be set when receiving SET_VRING_ADDR let's
fetch the 'used' index from the guest when receiving that message.
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Signed-off-by: German Maglione <gmaglione@redhat.com>
In the previous commit I forgot to update the version in
vhost/Cargo.toml, let's set it to 0.8.1
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
We experienced a small dependency issue with the `vm-memory` crate
features, let's release this version to fix it.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Since 4029089f ('vhost: Add support for Xen memory mappings') the
feature backend-mmap of the vm-memory crate is no longer just a
dev-dependency, as we're unconditionally importing GuestMemoryMmap from
'src/backend.rs'. Make it a general build dependency.
Signed-off-by: Sergio Lopez <slp@redhat.com>
Release a new version with Xen support.
We broke the build with the default features, but not yet made the
release, so this should be the real release.
Fixes: b128901 ("vhost: Release v0.8.0")
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
The `vhost-user` feature isn't enabled by default and using it without
protection in backend.rs makes the vhost only build fails.
Fix it by protecting it with the `#[cfg]` block.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Migrate to a newer version of the vhost and other dependencies and add
support for xen memory mappings. Add a corresponding xen feature for
vhost-user-backend crate.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Automatically enable the VhostUserProtocolFeatures::XEN_MMAP feature for
backends for Xen specific builds. With these the backends don't need to
enable this feature and can directly support Xen.
Suggested-by: Erik Schilling <erik.schilling@linaro.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The vm-memory crate now supports Xen specific memory mappings via a
special feature: "xen".
Add a corresponding feature for vhost crate and add support for Xen
memory regions. Update various dependencies to align to the same version
of vm-memory crate.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
No need to repeat the struct definition here. The only purpose is to
register an event_fd at epoll if one exists.
Signed-off-by: Erik Schilling <erik.schilling@linaro.org>
A lot of tests are creating objects of this structure directly, it would
be better if they all use a function instead to do so.
This will also be beneficial for future commits where more fields will
be added to this structure.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
VhostUserSingleMemoryRegion contains an extra padding before
VhostUserMemoryRegion, and everything else remains the same. Lets reuse
the same structure instead of duplicating implementation here.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The spec specifies that on receiving `GET_VRING_BASE` the backend should
stop the vring, but not that it must be reset. This is intended for
`VHOST_USER_RESET_DEVICE`, also in this case the spec makes a
difference between stopping and disabling the ring.
The spec also doesn't forbid to send `VHOST_USER_SET_VRING_ENABLE` to
enable the vring after receiving `GET_VRING_BASE` or sending more
`GET_VRING_BASE` messages, which would always respond 0. Moreover, qemu
doesn't reset the vring either.
Signed-off-by: German Maglione <gmaglione@redhat.com>
Clippy warns saying:
error: this `impl` can be derived
Derive them instead to fix those.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
In rust-vmm-ci we are enabling `clippy::undocumented_unsafe_blocks` as
errors, so let's comment all unsafe blocks to avoid failures in the
CI.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Unlike other vhost backends (e.g. vhost-net and vhost-vsock), vDPA
backends can not work with host virtual address (HVA), instead they
expect I/O virtual address (IOVA). The IOVA can be mapped 1:1 with
guest physical address (GPA) when no IOMMU is involved. This is why
the default implementation of `set_vring_addr()` from Trait
`VhostBackend` is no longer working with vDPA backends. To solve this
issue, this patch provides a custom `set_vring_addr()` implementation
for Trait `VhostKernVdpa`.
Fixes: #164
Signed-off-by: Bo Chen <chen.bo@intel.com>
Set up the stage to release vhost v0.7.0 and vhost-user-backend v0.9.0
to accommodate to the new vm-memory, virtio-bindings and virtio-queue
releases.
Signed-off-by: Sergio Lopez <slp@redhat.com>
When the frontend sends the `GET_VRING_BASE` message, we should return
the vring's last available index and stop the vring. To return the
correct value we should not reset the queue before getting its value,
otherwise we will always return 0.
Signed-off-by: German Maglione <gmaglione@redhat.com>
`VhostBackend::set_vring_addr()` receives a vring config data which
contains the addresses of desc table, used ring and avail ring.
`VhostBackend::is_valid()` checks the addresses in the guest address space.
`VHOST_SET_VRING_ADDR` uses the addresses in the host address space.
However, the method doesn't convert those addresses.
To address this issue, the addresses passed by the config are checked in
the guest address space. Then, they are converted by
`VringConfigData::to_vhost_vring_addr()` into the host address space to
setup the vring on the kernel.
Signed-off-by: Xuewei Niu <niuxuewei.nxw@antgroup.com>
There are a lot of slave requests supported by vhost-user protocol, it
isn't just about FS_MAP and FS_UNMAP. Rename the files and declarations
to slave request specific names.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Since VhostUserMsgHeader implements ByteValued, it is supposed to be
safe to construct from any correctly-sized arbitrary byte array.
But that means we can do this:
let bytes = b"\xFF\xFF\xFF\xFF\x00\x00\x00\x00\x00\x00\x00\x00";
let header = VhostUserMsgHeader::<MasterReq>::from_slice(bytes).unwrap();
header.get_code()
constructing an invalid MasterReq, using only functions that are
marked as safe. Constructing an invalid enum value is undefined
behavior in Rust, so this API is unsound. This wasn't considered by
the safety comment in VhostUserMsgHeader::get_code, which only
considered the safety of requests that were valid enum variants.
If the vhost-user frontend process sends a message that the backend
doesn't recognise, that's exactly what will happen, so the UB can be
triggered from an external process (but a trusted one).
To fix this, we need to check whether the value is valid _before_
converting it. Req::is_valid is changed to be a non-instance method,
so it can be called before constructing the Req.
VhostUserMsgHeader::get_code is changed to return a Result, to
accomodate the case where the request number is not a valid value for
R.
Signed-off-by: Alyssa Ross <alyssa.ross@unikie.com>
Now that the values being sent here are properly required to be
ByteValued, we can use the safe functions provided by ByteValued to
convert them into slices, rather than using slice::from_raw_parts.
Signed-off-by: Alyssa Ross <alyssa.ross@unikie.com>
These functions were unsound because it was previously possible to
trigger UB with them, but they were not marked as unsafe.
Struct padding in Rust is uninitialized. So if a struct with padding
had been passed to either of these functions as the body, it would
have resulted in an uninitialized read, which is undefined behavior in
Rust.
By restricting body values to be ByteValued, we avoid this, because
types implementing ByteValued are guaranteed to be convertible to and
from byte slices.
We then need to declare some types to be ByteValued, so that they can
continue to be sent over the socket.
Signed-off-by: Alyssa Ross <alyssa.ross@unikie.com>
It's important to be able to tell the difference between a client
cleanly disconnecting (e.g. if a VM is shut down), and a partial
message transmission. To do this, introduce a new Disconnected error
variant, to be used only when recvmsg() returns 0 when trying to
receive a header, indicating the client disconnected after the last
message.
Signed-off-by: Alyssa Ross <alyssa.ross@unikie.com>
Update dependencies to use recommended versions and version syntax.
See: rust-vmm/community#136
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Convert the vhost git repository into a crate, which hosts vhost crate
for now. Support for vhost-user-backend and other crates will be added
later on.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
