This commit adds support for the vhost-user interface to the passt
network backend, enabling high-performance, accelerated networking for
guests using passt.
The passt backend can now operate in a vhost-user mode, where it
communicates with the guest's virtio-net device over a socket pair
using the vhost-user protocol. This offloads the datapath from the
main QEMU loop, significantly improving network performance.
When the vhost-user=on option is used with -netdev passt, the new
vhost initialization path is taken instead of the standard
stream-based connection.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This commit introduces support for passt as a new network backend.
passt is an unprivileged, user-mode networking solution that provides
connectivity for virtual machines by launching an external helper process.
The implementation reuses the generic stream data handling logic. It
launches the passt binary using GSubprocess, passing it a file
descriptor from a socketpair() for communication. QEMU connects to
the other end of the socket pair to establish the network data stream.
The PID of the passt daemon is tracked via a temporary file to
ensure it is terminated when QEMU exits.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Add a chapter to explain how to use passt(1) instead of '-net user'.
passt(1) can be connected to QEMU using UNIX socket or vhost-user.
With vhost-user, migration of the VM is allowed and internal state of
passt(1) is transfered from one side to the other
Bug: https://gitlab.com/qemu-project/qemu/-/issues/2827
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
In the doc sources, we have a few cross-reference targets with odd
names "pcsys_005fxyz". These are the legacy of the semi-automated
conversion of the old info docs to rST (the '005f' is because ASCII
0x5f is '_' and the old info link names had underscores in them).
Remove the targets which nothing links to, and rename the two targets
which are used to something a bit more descriptive.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230421163642.1151904-1-peter.maydell@linaro.org
Reviewed-by: Markus Armbruster <armbru@redhat.com>
