Merge tag 'bcachefs-2025-06-26' of git://evilpiepirate.org/bcachefs

Pull bcachefs fixes from Kent Overstreet:

 - Lots of small check/repair fixes, primarily in subvol loop and
   directory structure loop (when involving snapshots).

 - Fix a few 6.16 regressions: rare UAF in the foreground allocator path
   when taking a transaction restart from the transaction bump
   allocator, and some small fallout from the change to log the error
   being corrected in the journal when repairing errors, also some
   fallout from the btree node read error logging improvements.

   (Alan, Bharadwaj)

 - New option: journal_rewind

   This lets the entire filesystem be reset to an earlier point in time.

   Note that this is only a disaster recovery tool, and right now there
   are major caveats to using it (discards should be disabled, in
   particular), but it successfully restored the filesystem of one of
   the users who was bit by the subvolume deletion bug and didn't have
   backups. I'll likely be making some changes to the discard path in
   the future to make this a reliable recovery tool.

 - Some new btree iterator tracepoints, for tracking down some
   livelock-ish behaviour we've been seeing in the main data write path.

* tag 'bcachefs-2025-06-26' of git://evilpiepirate.org/bcachefs: (51 commits)
  bcachefs: Plumb correct ip to trans_relock_fail tracepoint
  bcachefs: Ensure we rewind to run recovery passes
  bcachefs: Ensure btree node scan runs before checking for scanned nodes
  bcachefs: btree_root_unreadable_and_scan_found_nothing should not be autofix
  bcachefs: fix bch2_journal_keys_peek_prev_min() underflow
  bcachefs: Use wait_on_allocator() when allocating journal
  bcachefs: Check for bad write buffer key when moving from journal
  bcachefs: Don't unlock the trans if ret doesn't match BCH_ERR_operation_blocked
  bcachefs: Fix range in bch2_lookup_indirect_extent() error path
  bcachefs: fix spurious error_throw
  bcachefs: Add missing bch2_err_class() to fileattr_set()
  bcachefs: Add missing key type checks to check_snapshot_exists()
  bcachefs: Don't log fsck err in the journal if doing repair elsewhere
  bcachefs: Fix *__bch2_trans_subbuf_alloc() error path
  bcachefs: Fix missing newlines before ero
  bcachefs: fix spurious error in read_btree_roots()
  bcachefs: fsck: Fix oops in key_visible_in_snapshot()
  bcachefs: fsck: fix unhandled restart in topology repair
  bcachefs: fsck: Fix check_directory_structure when no check_dirents
  bcachefs: Fix restart handling in btree_node_scrub_work()
  ...