[PATCH RFC server 00/11] vfio-user server in QEMU

[Jagannathan Raman <jag.raman@oracle.com>]

Hi,

This series adds on to the following series from
Elena Ufimtseva <elena.ufimtseva@oracle.com>:
[PATCH RFC 00/19] vfio-user implementation

QEMU enabled out-of-process device emulation with multi-process [1].
multi-process used a custom protocol to interact between the client
and server, which is not desirable.

The vfio-user user protocol [2] implements a VFIO based mechanism to interact
between the client and server. Since VFIO is a well-established specification,
it is preferable in terms of maintenance. It makes sense for multi-process to
switch to the vfio-user protocol.

Nutanix implemented the vfio-user protocol in their libvfio-user library. The
source for this library is located below:
https://github.com/nutanix/libvfio-user

Elena previously sent the patches for the vfio-user client.

This series implements a vfio-user server for QEMU. It includes the
libvfio-user as a git submodule to QEMU, and builds it along with QEMU.

We would like to make the following notes:
  - Some of the existing multi-process code would become obsolete, and would
    need to be removed. This series does not remove them to keep the number
    of patches to a minimum. We will address them subsequently.
  - The libvfio-user library needs json-c package to build. It looks like the
    GitLab CI images used for build test don't have this package. As such it
    causes build failure.

The patches from both series are available in the following github repo:
https://github.com/oracle/qemu.git
The vfio-user-client-server branch provides the same patches along with a
python script (scripts/vfiouser-launcher.py) to launch the VM.

Contributors:
John G Johnson <john.g.johnson@oracle.com>
John Levon <john.levon@nutanix.com>
Thanos Makatos <thanos.makatos@nutanix.com>
Elena Ufimtseva <elena.ufimtseva@oracle.com>
Jagannathan Raman <jag.raman@oracle.com>

We are looking forward to your comments and questions.

Thank you!

[1]: https://patchew.org/QEMU/20210210092628.193785-1-stefanha@redhat.com/
[2]: https://patchwork.kernel.org/project/qemu-devel/patch/20210614104608.212276-1-thanos.makatos@nutanix.com/

Jagannathan Raman (11):
  vfio-user: build library
  vfio-user: define vfio-user object
  vfio-user: instantiate vfio-user context
  vfio-user: find and init PCI device
  vfio-user: run vfio-user context
  vfio-user: handle PCI config space accesses
  vfio-user: handle DMA mappings
  vfio-user: handle PCI BAR accesses
  vfio-user: handle device interrupts
  vfio-user: register handlers to facilitate migration
  vfio-user: acceptance test

 configure                     |  11 +
 meson.build                   |  35 ++
 qapi/qom.json                 |  20 +-
 include/hw/remote/iohub.h     |   2 +
 migration/savevm.h            |   2 +
 hw/remote/iohub.c             |   6 +
 hw/remote/vfio-user-obj.c     | 754 ++++++++++++++++++++++++++++++++++++++++++
 migration/savevm.c            |  63 ++++
 .gitmodules                   |   3 +
 MAINTAINERS                   |   9 +
 hw/remote/meson.build         |   3 +
 hw/remote/trace-events        |  10 +
 libvfio-user                  |   1 +
 tests/acceptance/vfio-user.py |  94 ++++++
 14 files changed, 1011 insertions(+), 2 deletions(-)
 create mode 100644 hw/remote/vfio-user-obj.c
 create mode 160000 libvfio-user
 create mode 100644 tests/acceptance/vfio-user.py

-- 
1.8.3.1