Commit Graph
7 Commits
Author SHA1 Message Date
6fb21c9ec0 filer: copy a remote-only entry on the remote when renaming it (#11709)
* filer: copy a remote-only entry on the remote when renaming it

Renaming a file under a remote.mount whose content exists only on the
remote (never cached, or remote.uncache'd) lost it: the new entry kept
the old RemoteEntry, deleting the old entry deleted the old object, and
with no chunks nothing ever wrote the new key. filer.remote.sync could
not finish the rename either, since the old object was already gone.

moveSelfEntry now copies such an entry's object to the new key before
it touches anything, and the new entry gets the RemoteEntry of the
copy. The copy is a new optional RemoteStorageObjectCopier interface,
implemented for S3 with CopyObject up to 5 GB and UploadPartCopy above
that; the multipart copy carries the source's metadata and, where the
remote supports tagging, its tags. When an existing target is
overwritten, its delete keeps the remote object (the copy replaced it)
and its event is marked metadata-only so the sync leaves it alone too.

A remote-only rename that leaves its mount, or whose remote cannot
copy, is refused instead of deleting the only copy. Empty entries and
entries with local data rename as before.

UpdateFileMetadata builds its copy source with the same helper, which
escapes each key segment and keeps the slashes.

* filer: delete a copied rename's old object only after the commit

Review follow-ups:

- The old key of a copied remote-only entry, and the old directory of a
  rename that copied one, are now deleted once the rename has committed.
  A rename that fails after the copy leaves the source entry and its
  object in place, plus an extra object at the new key.
- Every part of a multipart copy is conditioned on the ETag the copy
  started from, so an object overwritten mid-copy fails the copy
  instead of mixing versions.
- Both copy paths keep the source's server-side encryption settings.
- filer.remote.sync no longer deletes a key that a remote-only entry
  holds by the time the delete event is processed: a file deleted and
  then replaced by a remote-only rename has its content only there.

* filer: do not sweep the old prefix of a directory rename that copied

Removing the old directory on the remote deletes everything under its
prefix. Run after the commit, that could also take an object another
rename copied in under the same path meanwhile. When a child was copied,
leave the prefix alone and delete only the copied children's old keys.

* filer: keep an old key a remote-only entry has retaken by cleanup time

A directory rename does not lock its children's paths, so between the
commit and the deferred delete of a copied child's old key another
rename can put a remote-only entry there, whose content is then only in
that object. Check the store before deleting.

* filer: keep a renamed entry's old object when the path lookup fails

The deferred delete must only run once the lookup shows no remote-only
entry at the old path. A failed lookup shows nothing, and an extra
object loses nothing.

* filer: copy over a remote-only rename target only after the commit

Copying the source object onto the target's key before the transaction
committed destroyed the target's only content, which a rolled-back
commit cannot restore. When the target is remote-only the copy now runs
after the commit: the new entry keeps the old key's stamp until the copy
lands and re-stamps it, the target's object is kept meanwhile, and a
failed copy keeps the old object so remote.sync can finish it.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* remote.sync: match the delete event's etag before deleting the object

A rename can copy another entry's content onto a key between the filer's
check and the remote delete, and the delete then removes the copy. The
delete event carries the object's etag; delete only when the live object
still matches it.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* filer: finish a rename's remote work outside the committed transaction

The SQL stores keep the transaction in the context and refuse every
call through it once it has committed. The work that runs after
CommitTransaction used that context, so on postgres2 the deferred
old-key delete could not look up the old path and kept the object, and
finishRemoteCopies could not read or stamp the entry. Both failed with
"sql: transaction has already been committed or rolled back" on every
copied rename; remote.sync cleaned up after them.

Keep the context from before the transaction for the work after the
commit. The rename test store gets a strict mode that fails calls
through a committed transaction the way database/sql does.

* filer: carry a deferred copy's stamp in the rename event; delete orphaned uploads

- The deferred copy stamps the entry with a plain UpdateEntry, which
  publishes no event, so the queued rename event still carried the old
  key's stamp to peer filers and subscribers. Give it the copy's
  RemoteEntry before it is sent. The two notify loops share the code now.
- remote.sync kept any object whose ETag changed since the delete. With
  no entry at the path that is an upload which finished after the
  delete, and keeping it leaves it on the remote for good. Look up the
  path first and keep a changed object only when an entry holds it.

* remote.sync: keep a changed object even with no entry at its path

Deleting a changed object when no entry holds the path also deletes a
copy a directory rename has written but not yet made visible, while a
delete of that path waits in the sync; the rename then removes the old
key and the content is gone. Keep any object whose ETag changed since
the delete, as before. An upload that finishes after the delete leaks
its object instead, which is the cheaper failure.

* filer: read a pending remote rename copy from the source key

A remote-only rename over a remote-only target commits before its copy
lands, so reads on the new path served the target's old object until the
copy stamped the entry — and indefinitely when the copy failed without
remote.sync running. The committed entry now records the renamed-from
path, and remote-only reads resolve that object's key while the stamp
is pending; the copy's stamp and the sync's completion stamp both clear
the marker.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* filer: stamp the rename event with the deferred copy's result

A remote-only rename over a remote-only target queued the new entry's
event with the source's stamp before the deferred copy ran. Peers
replaying it saved a stamp the copy had already superseded, and the
sync serving such a peer rejected the destination as a match and tried
to copy the deleted source. The event now carries the copy's result
and drops the pending-source marker once it lands.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* remote.sync: delete only the object the event's stamp describes

An object at a deleted key is not always the one the delete meant: a
rename copy can land before its filer entry is visible, and a rewrite
can upload over it. When the event recorded no remote stamp, or the
live stat cannot confirm the recorded etag, the delete now keeps the
object instead of treating it as a late upload.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* filer: tighten the pending rename source marker

Follow-ups to reading a pending remote rename copy from its source key:

- Only the filer sets the marker. The HTTP upload and tagging handlers
  store Seaweed-* request headers as extended attributes, so they skip
  this one, and a marker that leads out of the entry's own mount is
  ignored, so it cannot point reads at another remote.
- A pending entry renamed again copies from the marker's source, not
  from its own key, which still holds the old target's bytes. A further
  deferred rename keeps naming the original source; an immediate copy
  clears the marker.
- When remote.sync finds the destination already holding the content,
  it stamps the entry (clearing the marker) before deleting the source,
  and deletes the source only once the entry no longer reads it.
- A read that resolved the source just before the copy finished and
  the source went away retries with the entry as it is now.

* filer, remote.sync: follow a pending rename's source across renames

When a remote-only entry is renamed over another remote-only file and
the deferred copy fails, it reads the source key through its marker.
Renamed again the same way, the marker keeps naming that source, but:

- remote.sync completed each rename from the event's old key. For the
  second one that is the first target's old object, which it copied
  over the destination before clearing the marker. It now copies from
  the source the entry's marker names.
- For the first rename it found no entry at the new path and deleted
  the old key, which the later entry still reads. When the event's new
  entry carried a marker and the path is gone, it now leaves the key to
  the entry that moved on.
- When the filer copies a pending entry immediately on a later rename,
  it now also releases the source the copy read, after the commit and
  with the same checks as the old key.

* remote.sync: release a pending rename's source, the filer leaves it

The filer deleted a pending entry's source after copying it on a later
rename, but that rename locks only its own paths: another rename can
copy onto the source key before its entry is visible, and the cleanup
then deleted that copy. And deleting a pending entry never released its
source at all.

The filer now leaves marked sources alone. remote.sync releases one
when the pending entry is deleted, or when a later rename was copied
right away, and only while the live object is still the one the
entry's stamp describes and no remote-only entry holds the path: a
copy that landed there since has a different ETag and is kept.

* remote.sync: release a pending source when the renamed entry is cached

A rename copied right away left its pending source to remote.sync,
which released it only while the destination was still remote-only.
Cached before the sync got there, the destination took the other path
and the source stayed on the remote for good. Release it there too,
with the same checks.

* remote.sync: release a pending source only after the destination is safe

e6d6438 released the source a renamed entry's old version read before
the destination was uploaded. A cached destination that still carried
the pending marker then had nothing behind it: had its upload failed,
remote.uncache could drop its chunks and leave it reading a deleted
source. Release the source only after the upload is stamped, and only
when the entry no longer reads through a marker.

* remote.sync: delete a rename's old key only if it is still the renamed content

completeRemoteOnlyRename deleted the old key once the destination held
the content. Another rename onto the vacated path can copy its object
there before the sync reaches the first rename, and that copy was then
deleted with it. Delete the old key only while the live object is still
the one the renamed entry's stamp describes.

Also keep the pending-source marker out of DELETE ?tagging, which
clears every Seaweed-* attribute: the marker is not a tag, and losing it
points reads back at the old target's bytes.

* remote.sync: compare a rename's old key against the source's own stamp

A retry can find the renamed entry already stamped with the copy, and a
copy of a multipart source has another ETag, so the unchanged source
was kept and stayed on the remote. Carry the stamp the event recorded
for the source (or the pending entry's, for a marked source) and compare
against that.

---------

Co-authored-by: Chris Lu <chrislusf@users.noreply.github.com>
Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
2026-10-12 19:21:54 +08:00
Chris Lu cda43f1976 filer: do not 404 a TUS session on a transient chunk-load failure (#11153)
* filer: do not 404 a TUS session on a transient chunk-load failure

readTusSessionInfo already proved the session exists before
loadTusSessionChunks is called, so a failure there is a read failure,
not evidence the session is gone: a volume-server timeout or a
canceled request context surfaces through ListDirectoryEntries the
same way a missing session would.

Every such error was mapped to writeTusSessionNotFound, answering 404
to HEAD/PATCH and 204 to DELETE. A spec-compliant TUS client trusts
that and discards the session, orphaning every chunk it had committed
until the 24h expiry sweep, or forever if it never issues a DELETE.

Only an error matching filer_pb.ErrNotFound is now reported as not
found; anything else answers 500 so the client retries against the
same session instead of abandoning it.

* test: cover a TUS session's transient chunk-load failure

Adds a listErr hook to the in-memory test store, alongside the
existing commitErr/deleteErr, to simulate a store or RPC failure from
ListDirectoryEntries.

HEAD, PATCH and DELETE against a live session all answer with a
server error instead of a not-found status when the chunk listing
fails transiently, and the session is left on disk untouched. A
listing failure that genuinely means not found, filer_pb.ErrNotFound,
still answers 404 (204 for DELETE).
2026-09-04 16:39:24 -07:00
Chris Lu 44115c1051 filer: stop TUS uploads from turning into garbage (#10945)
* filer: store TUS sub-chunks through the regular chunk writer

A TUS sub-chunk was written with one assigned file id, retried up to
three times against that same id, and abandoned on failure: an attempt
that had landed on some replicas left a needle no session record and no
entry ever references, unreclaimable by vacuum.

dataToChunkWithSSE, which the regular write path uses per chunk, assigns
a fresh file id per attempt and hands back the file ids of failed
attempts, which are now freed the way the regular write path frees them.

* filer: retry a chunk write on a fresh volume when the server 5xxs

The filer's chunk writer assigns a fresh file id per attempt but only
retried transient network errors, so a volume filling up and turning
read-only mid-write failed the whole request even though the very next
assignment would have landed elsewhere. Every other write client already
routes this through ShouldReassignUpload; the filer's own write path now
does the same, for regular uploads and TUS sub-chunks alike.

* filer: export the chunk deletion queue

The filer test harness in weed/server builds filer.Filer as a struct
literal, so any code path reaching DeleteChunks dereferenced a nil
queue. Exported like the neighboring DeletionRetryQueue so the harness
can arm it.

* filer: complete a TUS upload whose chunk records overlap

A PATCH retried while its predecessor was still storing a sub-chunk -
a proxy timeout with an immediate retry is enough - records the same
range twice. HEAD computes Upload-Offset as the covered watermark and
reported the upload fully received, but completion demanded exactly
adjacent records and failed every attempt: the client concluded success
from offset == length, no entry was created, and the session eventually
expired, turning the entire upload into deleted needles for the vacuum
to chew through.

Completion now validates gapless coverage with the same watermark HEAD
uses. A record extending coverage joins the entry - the read path
resolves partial overlaps by ModifiedTsNs, and the raced copies carry
identical bytes - while a fully covered duplicate is freed once the
entry lands.

* filer: allow one mutating TUS request per session at a time

Nothing stopped two PATCHes from writing the same range concurrently:
both loaded the same offset, both passed the conflict check, and both
recorded their sub-chunks. A client whose request timed out in a proxy
retries immediately while the server side is still storing the buffered
sub-chunk, which is exactly that race.

A session now accepts one PATCH or DELETE at a time, the way tusd locks
uploads; a concurrent one is refused with 423 Locked, which TUS clients
retry, and HEAD keeps answering so progress polling is unaffected. The
chunk state is loaded under the claim, so a retried PATCH sees every
record its predecessor left and conflicts cleanly instead of duplicating
data.

* test: cover a TUS PATCH raced by its own retry

Stalls a PATCH mid-body over a raw connection, retries the same range
while it is in flight, and expects the retry refused with 423 Locked;
the upload then resumes from the reported offset and the final content
must be intact.

* filer: never free a TUS duplicate the entry still references

Coverage is computed from ranges, so a record fully covered by another
is treated as a duplicate no matter which needle it names. A malformed
record naming a file id the entry keeps would have had that needle freed
right after the entry landed - the corruption this change set exists to
stop. The duplicates are now freed in one batch, skipping any file id
the entry references; their records go with the session directory.

* test: bound the raw TUS connection reads

http.ReadResponse on the stalled PATCH's connection blocked until the
whole go test timeout if the filer never answered.

* filer: free the needles of chunk write attempts a retry replaced

A volume server stores the needle locally and only then fans out to the
replicas, so a replication failure 5xxs with the data already written.
Each attempt assigns its own file id, so once a later attempt lands
elsewhere nothing references the earlier ones: the caller only sees the
chunk that succeeded, and the failed ids were dropped.

They are now freed the way the caller frees them when the whole write
fails. Retrying on a 5xx makes this reachable on every read-only or full
volume, which is exactly the condition that filled the reporter's
volumes.
2026-08-25 09:24:51 -07:00
Chris Lu f46b2a1925 Stop the filer test helpers from pinning gigabytes of log buffers (#10560)
* log buffer: wake the interval loop on shutdown instead of sleeping through it

loopInterval parked in time.Sleep(flushInterval) and only re-checked
IsStopping when it woke, so a buffer shut down early kept both loop
goroutines - and the PreviousBufferCount+1 slabs of BufferSize they
reach - alive for up to a full interval afterwards. Select on shutdownCh
against a ticker instead, and give the loops a WaitGroup so a test can
observe that they exit.

* test: release the filers the server tests build

Every helper here left its filer's meta log buffer running, so each test
pinned PreviousBufferCount+1 buffers of BufferSize for the rest of the
run: ~3.5GB of live heap across the package, which overruns the address
space on linux/386 and kills the 32-bit job with an out-of-memory throw.

Thread the test through the helpers so the buffer is shut down on
cleanup, and shut the subscribe harness's filer down outright - its
deletion loop keeps the whole filer reachable otherwise. That harness
quiesces its flush path first, since Filer.Shutdown closes the store a
flush still in flight would write through.
2026-08-04 11:38:38 -07:00
Chris Lu 47b491b53c mount: version open file handles by filer log position (#10403)
* filer: stamp a log position on lookup and remote-cache responses

Metadata events are logged after their store write and stamped with the
filer clock. Reading that clock before serving an entry therefore gives
a timestamp with a causal guarantee: every event at or below it is
reflected in the returned entry. Clients caching filer state can use it
as the entry's version to order the response against subscription
events, including events committed before the call but delivered after
it.

* mount: version open file handles by filer log position

A subscription event refreshing an open handle did a second lookup; a
transient failure left the handle pinned to its old entry with no
retry, since the subscription cursor had already advanced. The deeper
problem is ordering: the handle is a cache written by three unordered
channels — the async invalidation worker, local mutation acks, and
open-time lookups — and overwriting cached state safely requires
knowing which write is newer.

The filer log timestamp is that order, and it now travels with every
value instead of being derived out of band. Events carry it natively;
lookup and remote-cache responses carry the log position stamped before
the serving read; mutation acks carry it in their returned event; and
the local store pairs each read with a version cursor advanced under
the same lock as the store write. Each handle records the version its
entry reflects, and one rule replaces the per-site reasoning: state at
or below the handle's version is old news and must not be installed.

The invalidation itself applies the event's own entry — no lookup, so
no transient-failure window — except under a cached parent, where the
store entry is the ordered merge of the event and anything applied
since, and its version outranks the event's. An uncached parent
receives no store writes, so a hit there would be a stale leftover
masking the event. A vacated path (delete, rename away) keeps the last
entry so unlinked-but-open reads still work. Directory builds version
the completed directory at the listing snapshot and re-invalidate
buffered events at that version, since their mid-build refresh ran
against an incomplete store.

The tests replay every race this replaces machinery for: rollback of a
newer local flush (queued, cached, and read-through), stale leftovers
under uncached parents, the build window including abort, handles
opened after an event was queued, events landing mid-lookup, and
undelivered events at remote-cache time across a filer failover.

* filer: serialize the log position fence with mutations, stamp mutation acks

The fence stamped before an unlocked entry read could precede state the
read returned: a mutation writes storage first and assigns its event
timestamp only at notify time, so a lookup racing that window handed
the mount an entry newer than its fence, and the event's later delivery
looked like fresh news — destroying dirty pages for a change the handle
already had. The mutation handlers already hold an exclusive per-path
lock across read, write, and notify; the lookup and remote-cache reads
now take it shared around the stamp and the read, making the fence
exact: everything at or below it is in the entry, nothing above it is.

A no-change update returns success without an event, leaving the mount
nothing to fence with even though the response confirms current state.
Create and update acks now carry a log position stamped under the same
lock, and the mount falls back to it whenever the ack has no event.

Also regenerate the VT marshalers, which the earlier generation missed:
without them a VT round-trip silently zeroed every log position.

* java: sync filer.proto

* mount: scope store versions to what they vouch for; atomic handle install

The store's version cursor claimed too much. Advanced by local mutation
acks and directory listing snapshots, it inflated the version of store
reads for unrelated paths whose events the subscription still owed, and
those events were then fenced out permanently. The cursor now tracks
subscription progress only — events arrive in log order, so everything
at or below it has been delivered for every path — and a completed
listing records its snapshot as a per-directory floor instead of a
global claim. Local acks never touch it: they version their own handle
directly. Buffered build events advance the cursor at delivery, since
their store write may never happen (abort) while their invalidation is
already queued; their read-through directory pairs no store read with
it, and rename fragments are applied first.

Concurrent first opens raced: a slower opener's older lookup could
overwrite the newer entry a faster opener had installed, while the
monotonic version kept the newer timestamp — an old entry fenced at a
new version, immune to every correcting event. Entry and version are
now installed as one decision under the handle map lock, and an install
that does not outrank the handle's version is dropped.

The remote-cache commit also escaped the fence: it wrote storage and
notified without the path lock, so a lookup's shared-locked fence and
read could land between the two and hand out the cached state
under-versioned. The commit now re-reads and writes under the exclusive
path lock, and backs off entirely when the entry changed during the
download — the concurrent writer supersedes the cached content.

* mount: floors gate store applies; installs respect handle users; renames join the fence

A directory floor certifies the listing state as of its snapshot, but a
delayed event at or below the floor was still applied to the store —
rolling the content back to pre-snapshot state while the floor kept
claiming the snapshot version, so the correcting events were fenced out
of every future read. Events are now gated against the affected
directory's floor, each half of a rename independently.

Fences are lower bounds: a listing or lookup can include a mutation
whose event has not been delivered yet, and that event later passes
every gate carrying state the handle already holds. Such a re-delivery
now advances the version without destroying dirty pages or reinstalling
the entry — invalidating local writes over a no-op was the real damage
in every remaining under-fence window, including the unlocked listing
snapshot, which no per-path lock can serialize.

The concurrent-open install moved from the map lock to the handle lock
every reader, writer, and invalidation synchronizes on, and rejects
what cannot improve the handle: dirty state (local writes would be
lost), unversioned lookup responses (they cannot outrank anything, and
two zero-version opens must not overwrite each other), and anything not
strictly newer. New handles are still fully initialized before the map
exposes them.

Renames committed metadata and emitted events with no path lock, so a
lookup could read the renamed state under a fence preceding its events.
Both rename handlers now hold the source and destination locks, ordered
by path, across commit and notification; descendants of a renamed
directory are not individually locked and rely on the no-op re-delivery
handling above.

* mount: per-entry store versions replace the cursor and directory floors

The store's aggregate versions — a global subscription cursor and
per-directory listing floors — were versions at coarser granularity
than the values they described, and every over-claiming bug in this
series traced to that gap: an aggregate vouching for state its source
never saw. Each store entry now carries the filer log position of the
write that produced it — the event that applied it, or the listing
snapshot that inserted it, recorded in the store's key-value space
under the same lock as the entry write. The store becomes what the
handle already is: a last-writer-wins register with one rule, install
only what outranks the current claim.

The cursor, the floors, their advancement rules, the pairing ordering
constraint, and the floor gating all collapse into that rule. Applies
are gated per entry, each half of a rename independently; an
unversioned local write clears the claim its content no longer proves;
version records lingering after a bulk folder wipe cannot fence a
recreate, since a claim only blocks while its entry exists. Listing
inserts are stamped at build completion, before the buffered replay so
newer replayed events override the stamp.

Filer side, the fence dance every versioned read must perform is now a
single choke point, fencedFindEntry, so a future read RPC gets the
lock-serialized stamp by construction rather than by convention.

* mount: judge no-op re-deliveries against an immutable base, not the live entry

The equal-state skip compared the incoming event to the live handle
entry, but local writes mutate the live entry — size, timestamps,
chunks — so a delayed event re-delivering the base the handle was
opened with no longer matched, and the installer destroyed the dirty
pages and rolled the entry back over nothing new. The handle now keeps
an immutable snapshot of the filer state it last installed or
acknowledged, refreshed at every install and mutation ack (flush acks
snapshot the request entry before the id mapping mutates it), and the
no-op judgment runs against that base: an event carrying the base
brings nothing, whatever the live entry has diverged to since.

* mount: tombstones for versioned deletes, absence floors, copy enrollment

Four gaps in the per-entry version protocol, all the same shape: a
versioned fact with nothing carrying its version.

A deletion is a fact about a path with no entry left to hold it —
clearing the record let a delayed older event resurrect the deleted
path, permanently, since the deletion's own redelivery is
dedup-suppressed. Versioned deletes now leave a tombstone record that
fences without an entry; renames tombstone their source the same way.
Plain records still only block while their entry exists, so records
lingering after a bulk folder wipe cannot fence a recreate.

A completed listing proves absences as well as presences: a name it
omitted was deleted as of the snapshot, and a delayed create below the
snapshot re-creates it. The snapshot is kept per directory strictly as
an absence fence, consulted only when a path has neither an entry nor
a version record — present entries carry their own versions and never
touch it, which is what separates this from the over-claiming floor it
replaces.

A rebuild against a pre-upgrade filer returns no snapshot; stamping
now clears the children's records in that case, so a reinserted entry
cannot reactivate the stale claim its previous incarnation left
behind and reject valid events below it.

Server-side copies installed the copied entry without enrolling in the
base protocol, so the copy's own event differed from the stale
pre-copy base and destroyed writes made to the destination after the
copy. The install now refreshes the base and takes its version from
the fenced readback.

* mount: deletion facts outlive the cache's knowledge of the entry

A versioned delete of a path the store held no entry for recorded
nothing, so a delayed older event recreated the path — permanently,
with the deletion's redelivery dedup-suppressed. The tombstone is now
written whenever a versioned event vacates a path: the deletion is a
fact about the path, not about what this cache happened to hold.

For an absent entry, the listing's absence floor now speaks whatever
older record remains: a tombstone at one position does not exhaust
what is known about the path when a newer snapshot has confirmed the
name still absent, and an event between the two was slipping past
both.

A committed copy whose readback failed installed a synthesized base
with local timestamps; the copy's real event legitimately differs from
it, and was read as foreign state — destroying writes made to the
destination after the copy. The handle now marks that its own event is
en route and adopts that event's state as the base without touching
the live entry or the dirty pages; the adoption is one-shot, so a
genuinely foreign event still invalidates.

* mount: authoritative acks cancel pending event adoption; tombstones scoped and pruned

The copy-event adoption flag could outlive its purpose: a flush after
the failed readback installs a newer base and advances the version, the
copy's own event is then version gated without consuming the flag, and
the next genuinely foreign event was silently adopted — base advanced,
live entry and dirty pages untouched — leaving the mount to later
overwrite that remote change. Every local acknowledgment now installs
its base through one helper that also cancels any pending adoption: the
ack supersedes the mutation the adoption was waiting for.

Tombstones were written for every versioned delete under the mount and
survived directory eviction by design, growing LevelDB with historical
deletions on delete-heavy mounts. They are now scoped to directories
whose cached state the fence actually protects — an uncached parent
never serves from the store nor applies the resurrecting insert — and a
completed listing prunes the direct-child tombstones its absence floor
supersedes, leaving only those above the snapshot. The store gains a
key-prefix visitor for the sweep.

* mount: acked saves install their value; trailer snapshots; direct-child prune range

A version must never advance without its value. saveEntry stamped any
open handle with the acknowledgment's version, but a handle opened
while the save was in flight holds the pre-mutation entry — stamping it
fenced out the events carrying the state it lacked, permanently, with
the local apply performing no invalidation and the redelivery
deduplicated. The acknowledged entry is now installed together with its
version, through the same guarded install the racing-open path uses:
under the handle lock, only when it outranks the handle, never over
dirty local writes.

Empty listings return no in-band snapshot — a snapshot-only response
would be read as an entry by older consumers — so directories that end
empty gained no absence floor and their tombstones were never pruned.
The filer now sends the snapshot in the stream trailer, which older
clients ignore, and the client reads it when no in-band snapshot
arrived. Empty directories get real floors, their tombstones prune,
and their buffered replays gain the snapshot filter instead of the
replay-all fallback.

Version records now encode the parent directory and name separated by
a NUL, making a directory's direct children one contiguous key range:
the tombstone prune scans exactly them under the cache lock, instead
of walking every descendant record — the whole store, for root.

* mount: fix dirty-page loss, uid/gid base, download race, copy adopt, leak; dedup

Correctness fixes from the versioned-invalidation review:

- A foreign delete/rename-away of a file held open with unflushed local
  writes destroyed the dirty pages unconditionally. A process may keep
  writing to an unlinked-but-open file and those writes were already
  acknowledged; preserve the pages when the handle is dirty.
- downloadRemoteEntry stored the handle's base with filer-side uid/gid
  while every candidate it is later compared against is in local form,
  so under a non-identity UidGidMapper an unchanged re-delivery looked
  foreign and force-destroyed dirty pages. Map the base to local.
- downloadRemoteEntry wrote the entry/base/version triple under only the
  handle's shared lock, so two concurrent reads of the same remote-only
  file could tear it. Serialize the install with a dedicated mutex
  (invalidation is already excluded by the exclusive handle lock).
- A committed server-side copy whose readback failed adopted the FIRST
  event past the version gate as its base; a foreign write delivered
  first was silently swallowed. Adopt only an event whose content
  matches the synthesized base — the copy's own event — and install any
  other normally.
- The deferred-create path relied on AcquireFileHandle installing the
  passed entry on a pre-existing handle, which the version rework
  dropped. Restore that install in the compat wrapper; the versioned
  open path keeps its gated install.

Growth and hot-path cost:

- Per-entry version records and tombstones leaked when a directory was
  evicted or read-through without a rebuild. An uncached directory
  gates its own inserts, so its records fence nothing; clear a
  directory's child version records when it is wiped for eviction.
- FindEntry paid for the version KvGet on every lookup/getattr cache hit
  and threw it away. FindEntry now reads only the entry; the hot
  lookupEntry cache-hit path skips the version entirely.

Cleanups:

- Extract ackVersionTsNs over the shared response interface, replacing
  the metadata-event-else-log-ts snippet copy-pasted at four ack sites.
- Extract acquireRenamePathLocks, replacing the verbatim sorted
  two-path lock fence in both rename handlers.

* mount: no resurrection on foreign delete, version no-event acks, gate downloads, tighten copy adopt

Follow-ups to the review patches:

- Preserving dirty pages on a foreign delete let the next flush pass the
  isDeleted guard and CreateEntry, resurrecting the remotely-unlinked
  name. Mark the handle deleted in the vacate branch: the open fd can
  still read its buffered writes, but a flush no longer recreates the
  file.
- A no-event acknowledgment (log fence only) synthesized a metadata
  event with TsNs 0, so the cache stored the entry unversioned and an
  older subscriber event rolled it back. Stamp the synthesized event
  with the ack's log position at all four ack sites.
- downloadRemoteEntry serialized its install but did not check the
  version, so an older response arriving last overwrote the entry/base
  while the monotonic version kept the newer value, fencing corrections
  out. Install only when the response is at least as new as the handle.
- sameEntryContent compared only size and chunks, so a foreign chmod
  with unchanged content was adopted as the copy's own event. Compare
  everything except server-assigned timestamps, so a metadata-only
  foreign change installs instead.

* mount: trim comments to the non-obvious why

The versioning work accumulated multi-line comment blocks restating what
the code says. Keep the constraint a reader cannot derive — why a fence
is exact, why a version must not advance without its value, why an
uncached parent's records fence nothing — and drop the rest.

* mount: distinguish rename from delete, tighten the download and adopt gates

- A rename emits a nil old-path invalidation just like an unlink, so the
  vacate branch marked the handle deleted and later writes through the
  already-open descriptor were skipped instead of persisted. Carry the
  delete/rename distinction on the invalidation and mark only an actual
  delete.
- The remote-download install accepted an unversioned response
  regardless of the handle's version, so during a rolling upgrade a
  delayed response could install stale content under a newer version.
  Require the response to be at least as new, with one exception: a
  handle still lacking local chunks takes the content anyway — it cannot
  read without it — but does not claim the response's log position.
- Copy-event adoption returned without installing, so a foreign touch
  arriving before the copy's own event lost its timestamps. Content is
  unchanged either way, so the dirty pages stay valid; a clean handle now
  takes the entry, while a dirty one keeps its diverged version.

* mount: one directory floor instead of a record per child; agree on TTL

Review feedback:

- Build completion wrote one KV record per direct child inside the cache
  write lock, so a large directory stalled every other cache operation
  for O(children) store writes. The directory's listing snapshot already
  covers every child it saw; make that floor the version for any child
  without a record of its own, and a child earns a record only when a
  later event touches it. One map write per build replaces the per-child
  writes, with the same fencing.
- The presence probe read the store directly and so counted a
  TTL-expired entry as present, judging the path by a record describing
  content that has logically vanished. It now applies the same expiry
  the read path does, and an expired path falls back to its directory
  floor.
- Preserve ErrNotFound identity when the commit-time re-read finds the
  object deleted, so callers still surface a 404.
- Assert the rename-away source fence timestamp in the invalidation test.

Also record the tombstone ceiling: distinct deleted names in a cached
directory accumulate until it is rebuilt or evicted, which prunes
everything at or below the new snapshot.

* mount: pin the fence's clock domain instead of letting skew decide

A log-position fence is stamped by one filer's clock under that filer's
in-process lock, so comparing it to an event another filer logged is
comparing two unrelated clocks. The two error directions are not equally
costly: applying an event the fence already covered is a re-apply the
base-equality check absorbs, while skipping one it does not cover leaves
the handle holding exactly the state the event was meant to correct,
with the subscription cursor already past it — the unhealable staleness
this whole PR exists to remove.

So refuse to guess. Fences now carry the signature of the filer that
stamped them, and a handle records it alongside the position. An event
is only fenced out when the filer that logged it is the one that stamped
the fence — the logging filer appends its own signature, so its presence
identifies the clock domain. Events from any other filer are applied.
Positions taken from events keep comparing as before; the subscription
already delivers those in order.

The invalidation callback takes a struct now: it carries the path,
entry, position, delete/rename distinction, and signatures, and was
about to need a fifth positional parameter.

* mount: follow a foreign rename; key page invalidation on content, not equality

- A rename's old-path invalidation now carries the destination, and the
  handle follows the file there: an open fd tracks the inode, and leaving
  it on the old path made its next flush recreate that name instead of
  updating the renamed file.
- Dirty pages overlay content, so only a content change invalidates them.
  Keying that on exact equality meant any timestamp-only event destroyed
  them, which the copy-adoption marker existed to paper over — a foreign
  touch could consume the marker and leave the copy's own event to drop
  the post-copy writes. Comparing content instead makes the marker
  unnecessary, so it is gone: a metadata-only event keeps the overlay,
  and a dirty handle keeps its diverged entry unless foreign content
  supersedes it.
- A remote download response that is merely older is now refused even
  when the handle still lacks chunks; only an unversioned one is taken
  (and claims no position), since an older response's content predates
  what the handle reflects.
- A refused or unversioned download no longer publishes to the metadata
  cache, where a zero-position event would clear the entry's version and
  let an older subscriber event roll the cache back.

* mount: page invalidation keys on content alone; unversioned writes claim no position

- sameEntryContent compared everything but timestamps, so a foreign
  chmod, chown, or xattr change counted as a content change and
  destroyed the dirty-page overlay. It was strict only to serve the
  copy-adoption marker, which is gone; its one caller now asks the
  question it actually needs — did the bytes change — so metadata-only
  events leave the overlay alone.
- A rename over an existing file destroys that file, but its open handle
  was left live and still pointed at the name the renamed source now
  occupies, so its flush could overwrite it. MovePath already reports the
  displaced inode; mark that handle deleted.
- An acknowledgment was refused whenever its position was numerically
  lower, even when a different filer stamped the fence it lost to. Two
  known, differing signatures mean unrelated clocks, so the comparison no
  longer applies there; unknown signatures still compare as before.
- A local write with no log position behind it now records that
  explicitly instead of deleting its version record. Absence means the
  directory listing covers the path, which is why the snapshot floor
  applies; local content the listing never saw must not inherit it, or
  the events that would correct it are fenced out.

* mount: widen the existing lookup functions instead of forking WithVersion twins

The versioning work grew a parallel function for every accessor that
needed to return a log position — lookupEntryWithVersion beside
lookupEntry, maybeLoadEntryWithVersion beside maybeLoadEntry,
FindEntryWithVersion beside FindEntry, AcquireFileHandleWithVersion
beside AcquireFileHandle, advanceEntryVersion beside
advanceEntryVersionTsNs, plus a getPbEntryWithVersion wrapper and an
InsertListedEntriesForTest hook. Two names for one operation is two
places to keep in step, and the split let callers pick the one that
happened to compile.

Each pair is now the single original name carrying the position, with
callers that do not want it discarding it. filer_pb.GetEntry returns the
fence its response already carried rather than a mount-side wrapper
re-issuing the lookup, and InsertEntry takes the position its content
reflects rather than a test-only twin that inserted without one.

The one behavioural knot the merge exposed: AcquireFileHandle had been
installing the entry on a pre-existing handle only in its unversioned
form, which conflated 'the caller is authoritative' with 'the lookup had
no version'. Deferred create is the only caller that means the former,
so it now installs explicitly and the map function just acquires.
2026-07-23 17:44:02 -07:00
Chris Lu bce76e6e21 filer: serialize same-path mutations with a per-path lock (#9639)
CreateEntry is a FindEntry-then-write with no lock, so concurrent creates to the
same path race: OExcl can admit two creators, and a conditional check-then-act
has no atomicity. Add a per-path exclusive lock (util.LockTable, which evicts
idle keys so it stays bounded) on the FilerServer and take it in CreateEntry, so
the existence check and the write are atomic on this filer.

This is the local serialization point that lets callers route a key's writes to
its owner filer and drop the distributed lock for that key. AppendToEntry keeps
its distributed lock for now; it can move to the per-path lock once its callers
route to the owner.
2026-05-23 14:22:42 -07:00
Chris Lu ced2236cc6 Adjust rename events metadata format (#8854)
* rename metadata events

* fix subscription filter to use NewEntry.Name for rename path matching

The server-side subscription filter constructed the new path using
OldEntry.Name instead of NewEntry.Name when checking if a rename
event's destination matches the subscriber's path prefix. This could
cause events to be incorrectly filtered when a rename changes the
file name.

* fix bucket events to handle rename of bucket directories

onBucketEvents only checked IsCreate and IsDelete. A bucket directory
rename via AtomicRenameEntry now emits a single rename event (both
OldEntry and NewEntry non-nil), which matched neither check. Handle
IsRename by deleting the old bucket and creating the new one.

* fix replicator to handle rename events across directory boundaries

Two issues fixed:

1. The replicator filtered events by checking if the key (old path)
   was under the source directory. Rename events now use the old path
   as key, so renames from outside into the watched directory were
   silently dropped. Now both old and new paths are checked, and
   cross-boundary renames are converted to create or delete.

2. NewParentPath was passed to the sink without remapping to the
   sink's target directory structure, causing the sink to write
   entries at the wrong location. Now NewParentPath is remapped
   alongside the key.

* fix filer sync to handle rename events crossing directory boundaries

The early directory-prefix filter only checked resp.Directory (old
parent). Rename events now carry the old parent as Directory, so
renames from outside the source path into it were dropped before
reaching the existing cross-boundary handling logic. Check both old
and new directories against sourcePath and excludePaths so the
downstream old-key/new-key logic can properly convert these to
create or delete operations.

* fix metadata event path matching

* fix metadata event consumers for rename targets

* Fix replication rename target keys

Logical rename events now reach replication sinks with distinct source and target paths.\n\nHandle non-filer sinks as delete-plus-create on the translated target key, and make the rename fallback path create at the translated target key too.\n\nAdd focused tests covering non-filer renames, filer rename updates, and the fallback path.\n\nCo-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Fix filer sync rename path scoping

Use directory-boundary matching instead of raw prefix checks when classifying source and target paths during filer sync.\n\nAlso apply excludePaths per side so renames across excluded boundaries downgrade cleanly to create/delete instead of being misclassified as in-scope updates.\n\nAdd focused tests for boundary matching and rename classification.\n\nCo-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Fix replicator directory boundary checks

Use directory-boundary matching instead of raw prefix checks when deciding whether a source or target path is inside the watched tree or an excluded subtree.\n\nThis prevents sibling paths such as /foo and /foobar from being misclassified during rename handling, and preserves the earlier rename-target-key fix.\n\nAdd focused tests for boundary matching and rename classification across sibling/excluded directories.\n\nCo-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Fix etc-remote rename-out handling

Use boundary-safe source/target directory membership when classifying metadata events under DirectoryEtcRemote.\n\nThis prevents rename-out events from being processed as config updates, while still treating them as removals where appropriate for the remote sync and remote gateway command paths.\n\nAdd focused tests for update/removal classification and sibling-prefix handling.\n\nCo-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Defer rename events until commit

Queue logical rename metadata events during atomic and streaming renames and publish them only after the transaction commits successfully.\n\nThis prevents subscribers from seeing delete or logical rename events for operations that later fail during delete or commit.\n\nAlso serialize notification.Queue swaps in rename tests and add failure-path coverage.\n\nCo-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Skip descendant rename target lookups

Avoid redundant target lookups during recursive directory renames once the destination subtree is known absent.\n\nThe recursive move path now inserts known-absent descendants directly, and the test harness exercises prefixed directory listing so the optimization is covered by a directory rename regression test.\n\nCo-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* Tighten rename review tests

Return filer_pb.ErrNotFound from the bucket tracking store test stub so it follows the FilerStore contract, and add a webhook filter case for same-name renames across parent directories.\n\nCo-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix HardLinkId format verb in InsertEntryKnownAbsent error

HardLinkId is a byte slice. %d prints each byte as a decimal number
which is not useful for an identifier. Use %x to match the log line
two lines above.

* only skip descendant target lookup when source and dest use same store

moveFolderSubEntries unconditionally passed skipTargetLookup=true for
every descendant. This is safe when all paths resolve to the same
underlying store, but with path-specific store configuration a child's
destination may map to a different backend that already holds an entry
at that path. Use FilerStoreWrapper.SameActualStore to check per-child
and fall back to the full CreateEntry path when stores differ.

* add nil and create edge-case tests for metadata event scope helpers

* extract pathIsEqualOrUnder into util.IsEqualOrUnder

Identical implementations existed in both replication/replicator.go and
command/filer_sync.go. Move to util.IsEqualOrUnder (alongside the
existing FullPath.IsUnder) and remove the duplicates.

* use MetadataEventTargetDirectory for new-side directory in filer sync

The new-side directory checks and sourceNewKey computation used
message.NewParentPath directly. If NewParentPath were empty (legacy
events, older filer versions during rolling upgrades), sourceNewKey
would be wrong (/filename instead of /dir/filename) and the
UpdateEntry parent path rewrite would panic on slice bounds.

Derive targetDir once from MetadataEventTargetDirectory, which falls
back to resp.Directory when NewParentPath is empty, and use it
consistently for all new-side checks and the sink parent path.
2026-03-30 18:25:11 -07:00