[Qemu-devel] [nbdkit PATCH 0/3] nbdkit support for new NBD fast zero

[Eric Blake <eblake@redhat.com>]

See the cross-post cover letter for details:
https://www.redhat.com/archives/libguestfs/2019-August/msg00322.html

Notably, this series did NOT add fast zero support to the file plugin
yet; there, I probably need to do more testing and/or kernel source
code reading to learn whether to mark fallocate() as potentially slow,
as well as to definitely mark ioctl(BLKZEROOUT) as definitely slow.
That will be a followup patch.

Eric Blake (3):
  server: Add internal support for NBDKIT_FLAG_FAST_ZERO
  filters: Add .can_fast_zero hook
  plugins: Add .can_fast_zero hook

 docs/nbdkit-filter.pod                  |  27 ++++--
 docs/nbdkit-plugin.pod                  |  74 +++++++++++---
 docs/nbdkit-protocol.pod                |  11 +++
 filters/delay/nbdkit-delay-filter.pod   |  15 ++-
 filters/log/nbdkit-log-filter.pod       |   2 +-
 filters/nozero/nbdkit-nozero-filter.pod |  41 ++++++--
 plugins/sh/nbdkit-sh-plugin.pod         |  13 ++-
 server/internal.h                       |   2 +
 common/protocol/protocol.h              |  11 ++-
 server/filters.c                        |  33 ++++++-
 server/plugins.c                        |  47 ++++++++-
 server/protocol-handshake.c             |   7 ++
 server/protocol.c                       |  46 +++++++--
 include/nbdkit-common.h                 |   7 +-
 include/nbdkit-filter.h                 |   3 +
 include/nbdkit-plugin.h                 |   2 +
 filters/blocksize/blocksize.c           |  12 +++
 filters/cache/cache.c                   |  20 ++++
 filters/cow/cow.c                       |  20 ++++
 filters/delay/delay.c                   |  28 +++++-
 filters/log/log.c                       |  16 ++--
 filters/nozero/nozero.c                 |  62 +++++++++++-
 filters/truncate/truncate.c             |  15 +++
 plugins/data/data.c                     |  14 ++-
 plugins/full/full.c                     |  12 +--
 plugins/memory/memory.c                 |  14 ++-
 plugins/nbd/nbd.c                       |  28 +++++-
 plugins/null/null.c                     |   8 ++
 plugins/ocaml/ocaml.c                   |  26 ++++-
 plugins/sh/call.c                       |   1 -
 plugins/sh/sh.c                         |  39 ++++++--
 plugins/ocaml/NBDKit.ml                 |  10 +-
 plugins/ocaml/NBDKit.mli                |   2 +
 plugins/rust/src/lib.rs                 |   3 +
 tests/test-eflags.sh                    | 122 +++++++++++++++++++++---
 tests/test-fua.sh                       |   4 +-
 36 files changed, 686 insertions(+), 111 deletions(-)

-- 
2.21.0