[Libguestfs] [nbdkit PATCH 0/4] More work with retry safety

I'm still working on another set of patches to have reopen call .finalize/.prepare (so that another filter can safely appear between retry and the plugin), but for tonight, these are the patches I think are ready to go. Eric Blake (4): retry: Handle can_fua and can_fast_zero changes tests: Test retry with different fua/fast-zero flags server: Close backends if a filter's .open fails server: Better documentation of .open ordering docs/nbdkit-filter.pod | 17 +++-- server/backend.c | 5 +- server/connections.c | 2 +- server/filters.c | 8 ++- filters/retry/retry.c | 20 ++++++ tests/test-layers-filter.c | 5 +- tests/test-layers.c | 14 ++-- tests/Makefile.am | 2 + tests/test-retry-zero-flags.sh | 126 +++++++++++++++++++++++++++++++++ 9 files changed, 183 insertions(+), 16 deletions(-) create mode 100755 tests/test-retry-zero-flags.sh -- 2.21.0