Re: [PATCH v5 06/12] nbd: Update qapi to support exporting multiple bitmaps

Since 'nbd-server-add' is deprecated, and 'block-export-add' is new to 5.2, we can still tweak the interface. Allowing 'bitmaps':['str'] is nicer than 'bitmap':'str'. This wires up the qapi and qemu-nbd changes to permit passing multiple bitmaps as distinct metadata contexts that the NBD client may request, but the actual support for more than one will require a further patch to the server. Signed-off-by: Eric Blake <eblake(a)redhat.com&gt; Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov(a)virtuozzo.com&gt; --- docs/system/deprecated.rst | 4 +++- qapi/block-export.json | 18 ++++++++++++------ blockdev-nbd.c | 13 +++++++++++++ nbd/server.c | 19 +++++++++++++------ qemu-nbd.c | 10 +++++----- 5 files changed, 46 insertions(+), 18 deletions(-) diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst index 905628f3a0cb..d6cd027ac740 100644 --- a/docs/system/deprecated.rst +++ b/docs/system/deprecated.rst @@ -268,7 +268,9 @@ the 'wait' field, which is only applicable to sockets in server mode '''''''''''''''''''''''''''''''''''''''''''''''''''''''' Use the more generic commands ``block-export-add`` and ``block-export-del`` -instead. +instead. As part of this deprecation, it is now preferred to export a +list of dirty bitmaps via ``bitmaps``, rather than a single bitmap via +``bitmap``. Human Monitor Protocol (HMP) commands ------------------------------------- diff --git a/qapi/block-export.json b/qapi/block-export.json index 893d5cde5dfe..c7c749d61097 100644 --- a/qapi/block-export.json +++ b/qapi/block-export.json @@ -74,10 +74,10 @@ # @description: Free-form description of the export, up to 4096 bytes. # (Since 5.0) # -# @bitmap: Also export the dirty bitmap reachable from @device, so the -# NBD client can use NBD_OPT_SET_META_CONTEXT with the -# metadata context name "qemu:dirty-bitmap:NAME" to inspect the -# bitmap. (since 4.0) +# @bitmaps: Also export each of the named dirty bitmaps reachable from +# @device, so the NBD client can use NBD_OPT_SET_META_CONTEXT with +# the metadata context name "qemu:dirty-bitmap:BITMAP" to inspect +# each bitmap. (since 5.2)

# @allocation-depth: Also export the allocation depth map for @device, so # the NBD client can use NBD_OPT_SET_META_CONTEXT with @@ -88,7 +88,7 @@ ## { 'struct': 'BlockExportOptionsNbd', 'data': { '*name': 'str', '*description': 'str', - '*bitmap': 'str', '*allocation-depth': 'bool' } } + '*bitmaps': ['str'], '*allocation-depth': 'bool' } }

# @NbdServerAddOptions: @@ -100,12 +100,18 @@ # @writable: Whether clients should be able to write to the device via the # NBD connection (default false). # +# @bitmap: Also export a single dirty bitmap reachable from @device, so the +# NBD client can use NBD_OPT_SET_META_CONTEXT with the metadata +# context name "qemu:dirty-bitmap:BITMAP" to inspect the bitmap +# (since 4.0). Mutually exclusive with @bitmaps, and newer +# clients should use that instead.

+# # Since: 5.0 ## { 'struct': 'NbdServerAddOptions', 'base': 'BlockExportOptionsNbd', 'data': { 'device': 'str', - '*writable': 'bool' } } + '*writable': 'bool', '*bitmap': 'str' } } ## # @nbd-server-add: