[PATCH v8 00/20] Initial support for multi-process qemu

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

Hello

This is the v8 of the patchset. Thank you very much for the
detailed feedback for v7. We appreciate your time. We believe
we have address all the comments for v7 in the current series.

The broader items we have addressed in this series are as follows:
- Removed the main channel / control channel.
- Enabled 1:1 mapping between irqfd:PCIDevice, moving away from
  shared interrupt lines to avoid collision between irqfds
- Defined an object type named “remote-object” that connects the
  device with its fd in the remote process. This object limits the
  number of remote devices to 1 per process to alleviate security
  concerns with multiple devices per process. We are addressing the
  authentication mechanism for multiple devices in the
  VFIO-over-socket proposal.

To touch upon the brief history of this project, we posted the
Proof Of Concept patches before the BoF session in 2018.
Subsequently, we posted RFC v1 [1], RFC v2 [2], RFC v3 [3],
RFC v4 [4], v5 [5], v6 [6] and v7 [7] of the patch series.
Following people contributed to the design and
implementation of this project:

Stefan Hajnoczi <stefanha@redhat.com>
Konrad Wilk <konrad.wilk@oracle.com>
Kanth Ghatraju <kanth.ghatraju@oracle.com>
John G Johnson <john.g.johnson@oracle.com>
Elena Ufimtseva <elena.ufimtseva@oracle.com>
Jagannathan Raman <jag.raman@oracle.com>


We would like to thank QEMU community for your feedback in the
design and implementation of this project.

For the full concept writeup about QEMU multi-process, please refer to
docs/devel/qemu-multiprocess.rst. Also see docs/qemu-multiprocess.txt for
usage information.


We welcome all your ideas, concerns, and questions for this patchset.

[POC]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg566538.html
[1]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg602285.html
[2]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg624877.html
[3]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg642000.html
[4]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg655118.html
[5]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg682429.html
[6]: https://www.mail-archive.com/qemu-devel@nongnu.org/msg697484.html
[7]: https://patchew.org/QEMU/cover.1593273671.git.elena.ufimtseva@oracle.com/

Elena Ufimtseva (8):
  multi-process: add qio channel function to transmit
  multi-process: define MPQemuMsg format and transmission functions
  multi-process: add co-routines to communicate with remote
  multi-process: introduce proxy object
  multi-process: Forward PCI config space acceses to the remote process
  multi-process: heartbeat messages to remote
  multi-process: perform device reset in the remote process
  multi-process: add configure and usage information

Jagannathan Raman (11):
  memory: alloc RAM from file at offset
  multi-process: Add config option for multi-process QEMU
  multi-process: setup PCI host bridge for remote device
  multi-process: setup a machine object for remote device process
  multi-process: Initialize message handler in remote device
  multi-process: Associate fd of a PCIDevice with its object
  multi-process: setup memory manager for remote device
  multi-process: PCI BAR read/write handling for proxy & remote
    endpoints
  multi-process: Synchronize remote memory
  multi-process: create IOHUB object to handle irq
  multi-process: Retrieve PCI info from remote process

John G Johnson (1):
  multi-process: add the concept description to
    docs/devel/qemu-multiprocess

 MAINTAINERS                     |  26 ++
 backends/hostmem-memfd.c        |   2 +-
 configure                       |  11 +
 docs/devel/index.rst            |   1 +
 docs/devel/multi-process.rst    | 966 ++++++++++++++++++++++++++++++++++++++++
 docs/multi-process.rst          |  67 +++
 exec.c                          |  11 +-
 hw/Makefile.objs                |   1 +
 hw/i386/Makefile.objs           |   4 +
 hw/i386/remote-memory.c         |  58 +++
 hw/i386/remote-msg.c            | 266 +++++++++++
 hw/i386/remote-obj.c            | 127 ++++++
 hw/i386/remote.c                |  79 ++++
 hw/misc/ivshmem.c               |   3 +-
 hw/pci-host/Makefile.objs       |   1 +
 hw/pci-host/remote.c            |  76 ++++
 hw/pci/Makefile.objs            |   2 +
 hw/pci/memory-sync.c            | 211 +++++++++
 hw/pci/proxy.c                  | 417 +++++++++++++++++
 hw/remote/Makefile.objs         |   1 +
 hw/remote/iohub.c               | 123 +++++
 include/exec/memory.h           |   2 +
 include/exec/ram_addr.h         |   2 +-
 include/hw/i386/remote-memory.h |  19 +
 include/hw/i386/remote-obj.h    |  42 ++
 include/hw/i386/remote.h        |  35 ++
 include/hw/pci-host/remote.h    |  31 ++
 include/hw/pci/memory-sync.h    |  27 ++
 include/hw/pci/pci_ids.h        |   3 +
 include/hw/pci/proxy.h          |  48 ++
 include/hw/remote/iohub.h       |  42 ++
 include/io/channel.h            |  24 +
 include/io/mpqemu-link.h        | 123 +++++
 include/qemu/mmap-alloc.h       |   3 +-
 io/Makefile.objs                |   2 +
 io/channel.c                    |  45 ++
 io/mpqemu-link.c                | 303 +++++++++++++
 scripts/mpqemu-launcher.py      |  49 ++
 softmmu/memory.c                |   3 +-
 util/mmap-alloc.c               |   7 +-
 util/oslib-posix.c              |   2 +-
 41 files changed, 3252 insertions(+), 13 deletions(-)
 create mode 100644 docs/devel/multi-process.rst
 create mode 100644 docs/multi-process.rst
 create mode 100644 hw/i386/remote-memory.c
 create mode 100644 hw/i386/remote-msg.c
 create mode 100644 hw/i386/remote-obj.c
 create mode 100644 hw/i386/remote.c
 create mode 100644 hw/pci-host/remote.c
 create mode 100644 hw/pci/memory-sync.c
 create mode 100644 hw/pci/proxy.c
 create mode 100644 hw/remote/Makefile.objs
 create mode 100644 hw/remote/iohub.c
 create mode 100644 include/hw/i386/remote-memory.h
 create mode 100644 include/hw/i386/remote-obj.h
 create mode 100644 include/hw/i386/remote.h
 create mode 100644 include/hw/pci-host/remote.h
 create mode 100644 include/hw/pci/memory-sync.h
 create mode 100644 include/hw/pci/proxy.h
 create mode 100644 include/hw/remote/iohub.h
 create mode 100644 include/io/mpqemu-link.h
 create mode 100644 io/mpqemu-link.c
 create mode 100755 scripts/mpqemu-launcher.py

-- 
1.8.3.1