Zygo Blaxell d384f3eec0 roots: ignore subvol when it is read-only and send workaround is enabled ...

Previously, when the bees send workaround is enabled, bees would
immediately advance the subvol's crawl status as if the entire subvol
had been scanned.

If the subvol is later made read-write, or if the workaround is disabled,
bees sees that the subvol has already been marked as scanned.  This is
an unfortunate result if the subvol is inadvertently marked read-only
or if bees is inadvertently run with the send workaround disabled.

Instead, (almost) completely ignore the subvol:  don't advance the crawl
pointer, don't consider the subvol in the list if searchable roots, and
don't consider the subvol when calculating min_transid for new subvols.

The "almost" part is:  if the subvol scan has not yet started, keep its
start timestamp current so it won't mess up subvol traversal performance
metrics.

Also handle exceptions while determining whether a subvol is read-only,
as those apparently do happen.

Signed-off-by: Zygo Blaxell <bees@furryterror.org>

2021-10-31 19:42:01 -04:00

36 KiB

Raw Blame History

View Raw