CP-11462 ZOA infrastructure for snapshot reference and hold management#121
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lyriclake wants to merge 3 commits into
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CP-11462 ZOA infrastructure for snapshot reference and hold management#121lyriclake wants to merge 3 commits into
lyriclake wants to merge 3 commits into
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Adds Rust bindings and safe wrappers for two new libzfs_core symbols
introduced in delphix/zfs CP-11462:
- lzc_list_snapshot_refs: enumerates snapshots in a pool that carry the
DS_FIELD_SNAPSHOT_REFERENCE ZAP entry, returning each snapshot's guid
and sender-assigned ref_id. Used by ZOA's child reconciler to recover
missing recv-refs and write missing delete-refs.
- lzc_list_pool_holds: enumerates user holds across every snapshot in a
pool, optionally filtered by tag prefix. Used by ZOA's parent
reconciler with prefix "snapref:" to find and release orphaned holds.
The safe wrappers (Zfs::list_snapshot_refs, Zfs::list_pool_holds)
mirror the existing HoldList iterator pattern. PoolHoldList flattens
the kernel's two-level snap -> { tag -> time } map into a
(snap, tag, created_at) iterator.
Bumps zfs-core and zfs-core-sys to 0.5.1-delphix0.
delphix/rust-libzfs does not have lzc_list_pool_holds in its ZFS kernel interface, so remove the sys binding and the Rust wrapper. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Problem
ZOA's snapshot reference-tracking work (CP-11226 / "remote provisioning")
needs a read-only enumeration from the kernel that no existing
libzfs_coresymbol provides:List every snapshot in a pool that carries the
DS_FIELD_SNAPSHOT_REFERENCEZAP entry, along with itsguidandsender-assigned
ref_id. The child reconciler uses this to recovermissing recv-refs and write missing delete-refs.
The corresponding C symbol
lzc_get_snapshot_refsis added indelphix/zfs CP-11462: https://github.com/delphix/zfs/pull/2232. This PR is the matching rust-libzfs side: without
a safe wrapper ZOA cannot call it.
Solution
Add an FFI declaration for
lzc_get_snapshot_refsinzfs-core-sys/src/bindings.rs, plus a matching safe wrapper inzfs-core/src/lib.rs:Zfs::get_snapshot_refs(fsname)returns aSnapshotRefListwhoseIntoIteratoryieldsSnapshotRef { name, guid, ref_id }triples.The list type mirrors the shape of the existing
HoldList/HoldListIterpair. The binding is hand-added rather than regeneratedso this PR doesn't churn unrelated bindgen output; the next regen
against an updated
libzfs_core.hwill pick it up identically becausegenerate-bindingsalready whitelistslzc_.*.Bumps
zfs-coreandzfs-core-systo0.5.1-delphix0.Testing Done
LIBZFS_CORE_LOOKUP_WITH=link cargo check -p zfs-core— clean.(The 11 warnings emitted are pre-existing
#[cfg(features = ...)]typos, untouched by this PR.)
zfs_object_agent list-snapshot-refs child-poolreturned one entry with the expected(guid, ref_id)after a layered send/recv. The all-pools form (
zfs_object_agent list-snapshot-refswith no args,using
zpool listenumeration) also returned the same entry correctly.pass-through over the C function plus standard nvlist
destructuring; the meaningful coverage lives in the kernel side
and in the consuming reconcilers in zettaobject (CP-11226).