On 3/26/19 4:17 PM, Richard W.M. Jones wrote:
The cow filter doesn't support trimming and we should assume the
underlying plugin is fully allocated too. Note that both of these
limitations might be lifted with a more advanced filter
implementation.
However we ought to support this in future because xz files contain
sparseness information, so add a note.
Stale copy-and-paste comment?
Also, since the series is mostly alphabetical, I suspect you're missing
4.5/15 for filters/cache/cache.c (blindly passing through .extents to
the underlying plugin); easiest is probably forcing .can_extents false,
but nicer would be remembering status of portions that we have cached
locally to avoid repeated callouts to the plugin.
ACK for the cow filter.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
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