[v4,0/5] remove libxenctrl usage from xenstored

Message

Jürgen Groß Dec. 17, 2024, 11:12 a.m. UTC

Xenstored is using libxenctrl for only one purpose: to get information
about state of domains.

This patch series is removing that dependency by introducing a new
stable interface which can be used by xenstored instead.

There was a RFC series sent out 3 years ago, which I have taken as a
base and by addressing all comments from back then.

The main differences since that RFC series are:

- Instead of introducing an new main hypercall for a stable management
  interface I have just added a new domctl sub-op, as requested in 2021.

- I have added a new library libxenmanage for easy use of the new
  stable hypervisor interface. Main motivation for adding the library
  was the recent attempt to decouple oxenstored from the Xen git tree.
  By using the new library, oxenstored could benefit in the same way as
  xenstored from the new interface: it would be possible to rely on
  stable libraries only.

- Mini-OS has gained some more config options recently, so it was rather
  easy to make xenstore[pvh]-stubdom independent from libxenctrl, too.

- By moving the CPU barrier definitions out of xenctrl.h into a new
  dedicated header xenstored code no longer needs to #include xenctrl.h,
  thus removing any xenctrl reference from xenstored code.

Please note that the last patch can be committed only after the related
Mini-OS patch "config: add support for libxenmanage" has gone in AND
the Mini-OS commit-id has been updated in Config.mk accordingly! The
Mini-OS patch has been Acked already, so it can go in as soon as patch
4 of this series (the one introducing libxenmanage) has been committed.

Changes in V2:
- new patch 1
- former patch 5 mover earlier, now patch 2 (can go in without the rest
  of the series)
- addressed comments

Changes in V3:
- addressed comments

Changes in V4:
- patches 1 and 3 of V3 dropped, as already committed
- addressed comments

Juergen Gross (5):
  tools: add a dedicated header file for barrier definitions
  xen: add bitmap to indicate per-domain state changes
  xen: add new domctl get_changed_domain
  tools/libs: add a new libxenmanage library
  tools/xenstored: use new stable interface instead of libxenctrl

 stubdom/Makefile                       |   8 +-
 stubdom/mini-os.mk                     |   1 +
 tools/9pfsd/io.c                       |   5 +-
 tools/flask/policy/modules/dom0.te     |   2 +-
 tools/flask/policy/modules/xen.if      |   4 +-
 tools/flask/policy/modules/xenstore.te |   1 +
 tools/include/xen-barrier.h            |  39 ++++++
 tools/include/xenctrl.h                |  28 +----
 tools/include/xenmanage.h              |  92 ++++++++++++++
 tools/libs/Makefile                    |   1 +
 tools/libs/ctrl/Makefile               |   2 +-
 tools/libs/manage/Makefile             |  10 ++
 tools/libs/manage/Makefile.common      |   3 +
 tools/libs/manage/core.c               | 168 +++++++++++++++++++++++++
 tools/libs/manage/libxenmanage.map     |   8 ++
 tools/libs/uselibs.mk                  |   2 +
 tools/xenstored/Makefile               |   2 +-
 tools/xenstored/Makefile.common        |   2 +-
 tools/xenstored/core.h                 |   1 -
 tools/xenstored/domain.c               |  52 +++-----
 tools/xenstored/lu.c                   |   1 +
 tools/xenstored/lu_daemon.c            |   1 +
 xen/common/domain.c                    | 130 +++++++++++++++++++
 xen/common/domctl.c                    |  18 ++-
 xen/common/event_channel.c             |  26 +++-
 xen/include/public/domctl.h            |  26 ++++
 xen/include/xen/event.h                |   7 ++
 xen/include/xen/sched.h                |   5 +
 xen/include/xsm/dummy.h                |   8 ++
 xen/include/xsm/xsm.h                  |   6 +
 xen/xsm/dummy.c                        |   1 +
 xen/xsm/flask/hooks.c                  |   7 ++
 xen/xsm/flask/policy/access_vectors    |   2 +
 33 files changed, 595 insertions(+), 74 deletions(-)
 create mode 100644 tools/include/xen-barrier.h
 create mode 100644 tools/include/xenmanage.h
 create mode 100644 tools/libs/manage/Makefile
 create mode 100644 tools/libs/manage/Makefile.common
 create mode 100644 tools/libs/manage/core.c
 create mode 100644 tools/libs/manage/libxenmanage.map