Re: [PATCH v2 00/20] Add qemu-storage-daemon

[Kevin Wolf <kwolf@redhat.com>]

[-- Attachment #1: Type: text/plain, Size: 6358 bytes --]

Am 28.02.2020 um 12:16 hat Stefan Hajnoczi geschrieben:
> On Mon, Feb 24, 2020 at 03:29:48PM +0100, Kevin Wolf wrote:
> > This series adds a new tool 'qemu-storage-daemon', which can be used to
> > export and perform operations on block devices. There is some overlap
> > between qemu-img/qemu-nbd and the new qemu-storage-daemon, but there are
> > a few important differences:
> > 
> > * The qemu-storage-daemon has QMP support. The command set is obviously
> >   restricted compared to the system emulator because there is no guest,
> >   but all of the block operations that are not tied to gues devices are
> >   present.
> > 
> >   This means that it can access advanced options or operations that the
> >   qemu-img command line doesn't expose. For example, blockdev-create is
> >   a lot more powerful than 'qemu-img create', and qemu-storage-daemon
> >   allows to execute it without starting a guest.
> > 
> >   Compared to qemu-nbd it means that, for example, block jobs can now be
> >   executed on the server side, and backing chains shared by multiple VMs
> >   can be modified this way.
> > 
> > * The existing tools all have a separately invented one-off syntax for
> >   the job at hand, which usually comes with restrictions compared to the
> >   system emulator. qemu-storage-daemon shares the same syntax with the
> >   system emulator for most options and prefers QAPI based interfaces
> >   where possible (such as --blockdev), so it should be easy to make use
> >   of in libvirt.
> > 
> >   The exception is --chardev, for which not clear design for a QAPIfied
> >   command line exists yet. We'll consider this interface unstable until
> >   we've figured out how to solve it. For now it just uses the same
> >   QemuOpts-based code as the system emulator.
> > 
> > * While this series implements only NBD exports, the storage daemon is
> >   intended to serve multiple protocols and its syntax reflects this. In
> >   the past, we had proposals to add new one-off tools for exporting over
> >   new protocols like FUSE or TCMU.
> > 
> >   With a generic storage daemon, additional export methods have a home
> >   without adding a new tool for each of them.
> > 
> > The plan is to merge qemu-storage-daemon as an experimental feature with
> > a reduced API stability promise in 5.0.
> > 
> > Kevin Wolf (20):
> >   qemu-storage-daemon: Add barebone tool
> >   stubs: Add arch_type
> >   block: Move system emulator QMP commands to block/qapi-sysemu.c
> >   block: Move common QMP commands to block-core QAPI module
> >   block: Move sysemu QMP commands to QAPI block module
> >   qemu-storage-daemon: Add --blockdev option
> >   qapi: Flatten object-add
> >   qemu-storage-daemon: Add --object option
> >   qemu-storage-daemon: Add --nbd-server option
> >   blockdev-nbd: Boxed argument type for nbd-server-add
> >   qemu-storage-daemon: Add --export option
> >   qemu-storage-daemon: Add main loop
> >   qemu-storage-daemon: Add --chardev option
> >   stubs: Update monitor stubs for qemu-storage-daemon
> >   qapi: Create 'pragma' module
> >   monitor: Create QAPIfied monitor_init()
> >   qmp: Fail gracefully if chardev is already in use
> >   hmp: Fail gracefully if chardev is already in use
> >   monitor: Add allow_hmp parameter to monitor_init()
> >   qemu-storage-daemon: Add --monitor option
> > 
> >  qapi/block-core.json                 | 730 +++++++++++++--------------
> >  qapi/block.json                      | 512 +++++++++++--------
> >  qapi/control.json                    |  37 ++
> >  qapi/pragma.json                     |  24 +
> >  qapi/qapi-schema.json                |  25 +-
> >  qapi/qom.json                        |  12 +-
> >  qapi/transaction.json                |   2 +-
> >  configure                            |   2 +-
> >  include/block/nbd.h                  |   1 +
> >  include/monitor/monitor.h            |   6 +-
> >  include/qom/object_interfaces.h      |   7 +
> >  include/sysemu/arch_init.h           |   2 +
> >  block/qapi-sysemu.c                  | 590 ++++++++++++++++++++++
> >  blockdev-nbd.c                       |  40 +-
> >  blockdev.c                           | 559 --------------------
> >  chardev/char.c                       |   8 +-
> >  gdbstub.c                            |   2 +-
> >  hw/block/xen-block.c                 |  11 +-
> >  monitor/hmp-cmds.c                   |  21 +-
> >  monitor/hmp.c                        |   8 +-
> >  monitor/misc.c                       |   2 +
> >  monitor/monitor.c                    |  86 ++--
> >  monitor/qmp-cmds.c                   |   2 +-
> >  monitor/qmp.c                        |  11 +-
> >  qemu-storage-daemon.c                | 340 +++++++++++++
> >  qom/qom-qmp-cmds.c                   |  42 +-
> >  stubs/arch_type.c                    |   4 +
> >  stubs/monitor-core.c                 |  21 +
> >  stubs/monitor.c                      |  17 +-
> >  tests/test-util-sockets.c            |   4 +-
> >  scripts/qapi/gen.py                  |   5 +
> >  Makefile                             |  37 ++
> >  Makefile.objs                        |   9 +
> >  block/Makefile.objs                  |   4 +-
> >  monitor/Makefile.objs                |   2 +
> >  qapi/Makefile.objs                   |   7 +-
> >  qemu-deprecated.texi                 |   4 +
> >  qom/Makefile.objs                    |   1 +
> >  storage-daemon/Makefile.objs         |   1 +
> >  storage-daemon/qapi/Makefile.objs    |   1 +
> >  storage-daemon/qapi/qapi-schema.json |  26 +
> >  stubs/Makefile.objs                  |   2 +
> >  42 files changed, 1955 insertions(+), 1272 deletions(-)
> >  create mode 100644 qapi/pragma.json
> >  create mode 100644 block/qapi-sysemu.c
> >  create mode 100644 qemu-storage-daemon.c
> >  create mode 100644 stubs/arch_type.c
> >  create mode 100644 stubs/monitor-core.c
> >  create mode 100644 storage-daemon/Makefile.objs
> >  create mode 100644 storage-daemon/qapi/Makefile.objs
> >  create mode 100644 storage-daemon/qapi/qapi-schema.json
> 
> I haven't reviewed the patches in detail since they are mostly concerned
> with command-line interfaces and monitor changes.
> 
> Acked-by: Stefan Hajnoczi <stefanha@redhat.com>

Thanks, applied to the block branch.

Kevin

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 801 bytes --]