* fix 11400
* persist failed-recovery quarantine and harden rollback
- record the unavailable state in a .unavailable marker, fsync it, and
re-arm it on load so a restart cannot serve an unverified pair
- quarantine the volume so heartbeats stop advertising it
- block MarkVolumeWritable while unavailable, rechecked under noWriteLock
- fail every request of a failed batch, not only the succeeded ones
- restore the needle map and truncate .dat on inline fsync rollback failure
- add truncateIndex for the sorted-file needle map
- mirror the fail-closed semantics in the Rust volume server
* volume: erase rolled-back mappings instead of leaving tombstones
A rolled-back batch or failed inline write used Delete() to undo a
needle that did not exist beforehand, leaving a tombstoned map entry
whose stale offset makes the next write to that needle fail reading a
header that no longer exists. Add removeMapping/restoreMapping to the
mappers so recovery erases entries that were absent before the batch
and reinstates the exact prior offset/size for ones that were,
including tombstones. The index row still goes through Delete so a
replay forgets the needle.
* volume: gate bulk readers on unavailable and fsync the marker's dir
- fsync_dir(&self.dir) synced the volume dir's parent, not the dir
holding .unavailable; pass the marker path so the create survives
a host crash
- export UnavailableError and check it in ReadAllNeedles,
VolumeTailSender, VolumeIncrementalCopy, and IncrementalBackup so
replica-sync paths cannot stream or append data from an unverified
.dat/.idx pair; mirror on the Rust side via read_dat_slice,
read_all_needles, dat_scan_plan, and the incremental-copy handler
* volume: drop issue references from comments near touched code
* volume: stop active scans when the volume becomes unavailable
The stream entry-point checks ran once per RPC, so a volume quarantined
by a failed recovery mid-scan kept serving data. Recheck availability
per needle/chunk on the detached read paths: tail scan and heartbeat,
read-all, incremental copy, incremental backup writes, and the Rust
StreamingBody chunk reads. Rust incremental copy also rejects a
quarantined volume before sync_to_disk touches the backend.
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Co-authored-by: Chris Lu <chris.lu@gmail.com>
This is useful for doing backups on the data so we can accurately store the
last modified time, the compression state, and verify the crc.
Previously we were doing VolumeNeedleStatus and then an HTTP request which
needlessly read from the dat file twice.
