* mount: propagate request context through metadata lookups
The FUSE interrupt channel never reached the filer RPC: lookupEntry ran
its LookupEntry under context.Background(), so a stalled filer parked
ops like ListXAttr forever even after the kernel gave up on them.
Thread a context from each op's cancel channel through
maybeReadEntry, maybeLoadEntry, lookupEntry, ensureDirectoryVisited and
waitForPendingAsyncFlush; the existing withFilerClient attempt bound
turns it into both an interrupt and a deadline. A caller cancellation
now surfaces as EINTR instead of waiting out the RPC.
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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
* mount: reuse ctxFromCancel for the read path's interrupt bridge
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
* mount: regression tests for canceled and stalled filer lookups
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
* mount: thread ctx through AcquireHandle
Open, Create and Mknod all carry the request's cancel channel; let it
bound the pending-flush wait and metadata load inside AcquireHandle too.
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
* mount: keep flush waits and write sequences uninterruptible
The cancel-derived context must only cover metadata reads: an
interrupted Unlink or Rename that skips the pending-flush wait can
race the async write back into existence, and Link/Rename mutations
that run under a canceled context abort mid-sequence, strand the
rollback, and leave wrong hard-link counts. Restore the blocking flush
wait and run each op's write phase on context.Background(). Rmdir and
Unlink also propagate EINTR from the parent lookup instead of
proceeding past a permission check the interrupt prevented.
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
* mount: interrupt shared directory builds and directory reads
Waiters behind another request's singleflight directory build blocked
until it finished even when interrupted; switch the wait to DoChan so
the request context can abandon it. ReadDir paths now carry the
request context through EnsureListingFresh, cache listings and direct
reads, and map its cancellation to EINTR rather than EIO.
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
* mount: assert exact statuses in filer-stall regression tests
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
* mount: let read-side flush waits release on interrupt
waitForPendingAsyncFlush reports whether the flush actually finished:
lookupEntry and AcquireHandle return EINTR when the request is
abandoned mid-wait, while Unlink and Rename keep waiting on
context.Background() so the delete/rename still sees the flushed
state.
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
* mount: propagate interrupt through remaining lookup checks
Rename's source and destination permission lookups now return EINTR
on interrupt instead of skipping checkStickyBit or masking an
existing target, and the readdir preload visit maps cancellation to
EINTR like the other branches.
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
* mount: fail closed on errored rename prerequisite lookups
* mount: stop rmdir on interrupted target lookup, fail closed on dir lookup errors
---------
Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
readdir built dirPath.Child(name) for every child while entry.FullPath was
already that exact string, from NewFullPath in the meta cache store or from
FromPbEntry on the read-through path. One allocation per entry, and on a wide
tree with long paths that is most of what a listing allocates.
BenchmarkReadDirectory/kernel_readdirplus over 200k entries: 2,039,656 ->
1,839,318 allocs/op, 174.5 -> 167.8 MB/op, 152.6 -> 135.1 ms/op.
The cached readdir trims the head of the handle's entry stream as the
client walks past it; the read-through path never did, so a directory
too large to cache -- the only kind that takes that path -- was held
whole in the handle for the length of the walk. Hoist the trim to cover
both paths.
* mount: size the direct listing slice from the batch, not the offset
The limit passed here is skipCount+batchSize when a client resumes a
fresh handle partway through a directory, so preallocating for it turns
the client's cookie into an allocation: a readdir at offset 3,000,000
reserves 24MB before the first entry arrives, and an offset near the
uint32 ceiling asks makeslice for ~4.29e9 elements.
* mount: stop replaying a directory that shrank past the resume offset
A client that opens a fresh handle and resumes at a cookie from an
earlier, larger listing gets a preload that cannot reach the entry before
that offset. The resume name was then left empty and the follow-up batch
listed from the directory's first child again, so the client was handed
every name a second time.
The stream always runs from the first child, so failing to reach that
entry means the directory is simply shorter than the offset. That is the
end of it.
* mount: page a directory from where the store reached
The batch loader treated a short batch as the end of the directory, but
the meta cache drops an expired child after the store has already spent
it against the limit, so a batch that filled up could still deliver fewer
entries than asked for. A directory with a handful of expired children
would stop listing early and hide every child behind them; a whole batch
of expired ones truncated the listing to nothing.
ListDirectoryEntries now reports the name the store itself reached. That
is both the sound end-of-directory signal -- the store returning nothing
-- and the right cursor, since resuming from the last visible name would
re-read the dropped children every round and never get past a batch that
was entirely expired.
* mount: drop the entries a directory walk has already passed
entryStreamOffset was only ever written by reset, so the stream a handle
holds grew for the life of the walk and a directory was retained whole
even though nothing could read the entries behind the client's position
again. A 10M-entry walk parked millions of entries per handle, and
NFS-Ganesha opens several on the same directory.
Offsets index into the stream from entryStreamOffset, so advancing the
two together keeps them lined up. One entry is held back because the next
batch resumes from the name immediately before the offset. Seeking back
behind what is still held now restarts the directory, which is what the
offset scheme can honestly support -- it previously returned nothing.
