Merge tag 'bcachefs-2023-11-29' of

Pull more bcachefs bugfixes from Kent Overstreet:

 - bcache & bcachefs were broken with CFI enabled; patch for closures to
   fix type punning

 - mark erasure coding as extra-experimental; there are incompatible
   disk space accounting changes coming for erasure coding, and I'm
   still seeing checksum errors in some tests

 - several fixes for durability-related issues (durability is a device
   specific setting where we can tell bcachefs that data on a given
   device should be counted as replicated x times)

 - a fix for a rare livelock when a btree node merge then updates a
   parent node that is almost full

 - fix a race in the device removal path, where dropping a pointer in a
   btree node to a device would be clobbered by an in flight btree write
   updating the btree node key on completion

 - fix one SRCU lock hold time warning in the btree gc code - ther's
   still a bunch more of these to fix

 - fix a rare race where we'd start copygc before initializing the "are
   we rw" percpu refcount; copygc would think we were already ro and die

* tag 'bcachefs-2023-11-29' of (23 commits)
  bcachefs: Extra kthread_should_stop() calls for copygc
  bcachefs: Convert gc_alloc_start() to for_each_btree_key2()
  bcachefs: Fix race between btree writes and metadata drop
  bcachefs: move journal seq assertion
  bcachefs: -EROFS doesn't count as move_extent_start_fail
  bcachefs: trace_move_extent_start_fail() now includes errcode
  bcachefs: Fix split_race livelock
  bcachefs: Fix bucket data type for stripe buckets
  bcachefs: Add missing validation for jset_entry_data_usage
  bcachefs: Fix zstd compress workspace size
  bcachefs: bpos is misaligned on big endian
  bcachefs: Fix ec + durability calculation
  bcachefs: Data update path won't accidentaly grow replicas
  bcachefs: deallocate_extra_replicas()
  bcachefs: Proper refcounting for journal_keys
  bcachefs: preserve device path as device name
  bcachefs: Fix an endianness conversion
  bcachefs: Start gc, copygc, rebalance threads after initing writes ref
  bcachefs: Don't stop copygc thread on device resize
  bcachefs: Make sure bch2_move_ratelimit() also waits for move_ops