[PATCH v3 0/3] mm: clean up folio LRU and swap declarations

[Jianyue Wu]

This is a v2 of the previous single-patch cleanup:

  https://lore.kernel.org/r/20260407110002.204755-1-wujianyue000@xxxxxxxxx

The previous version moved the folio LRU helpers out of mm/swap.c in
one step. Based on review feedback from Johannes, Baoquan and Barry,
split the cleanup into smaller steps:

  - move the page-cluster sysctl next to swap readahead in mm/swap_state.c
  - rename mm/swap.c to mm/folio_lru.c after the swap-specific bits move out
  - move MM-internal reclaim declarations out of include/linux/swap.h

The first patch handles the swap-specific page-cluster state before the
file rename, so the rename commit only carries folio LRU code. The last
patch keeps the LRU helpers used outside mm/ in include/linux/swap.h and
moves the internal reclaim/workingset declarations to mm/internal.h.

This series is based on Christoph Hellwig's swap_ops series, which
moves swap I/O dispatch behind swap_ops and leaves mm/swap.c with less
swap-specific state. That makes the folio LRU cleanup more natural to
split out on top.

  https://lore.kernel.org/r/20260528124559.2566481-1-hch@xxxxxx

Signed-off-by: Jianyue Wu <wujianyue000@xxxxxxxxx>
---
Changes in v3:
- Update MAINTAINERS and documentation after mm/swap.c rename to
  mm/folio_lru.c (per David Hildenbrand's review)
- Move swap_readahead_setup() prototype from include/linux/swap.h to
  mm/swap.h (per Barry Song's review).  swap_readahead_setup() is only
  used inside mm/, and mm/vmscan.c already includes mm/swap.h.
- Add a CONFIG_SWAP=n stub for swap_readahead_setup(), because
  swap_state.o is only built when CONFIG_SWAP is enabled while
  kswapd_init() is built unconditionally.
- Link to v2: https://lore.kernel.org/r/20260531-ch-swap-series-plus-folio-lru-cleanup-v2-0-1b9a4ac255b4@xxxxxxxxx

---
Jianyue Wu (3):
      mm/swap: colocate page-cluster sysctl with swap readahead
      mm: move folio LRU code out of swap
      mm: move reclaim-internal declarations out of swap.h

 Documentation/admin-guide/sysctl/vm.rst |  2 +-
 Documentation/core-api/mm-api.rst       |  2 +-
 MAINTAINERS                             |  3 +-
 include/linux/swap.h                    | 75 +++------------------------------
 mm/Makefile                             |  2 +-
 mm/{swap.c => folio_lru.c}              | 38 +----------------
 mm/internal.h                           | 65 ++++++++++++++++++++++++++++
 mm/memfd.c                              |  1 +
 mm/swap.h                               |  8 +++-
 mm/swap_state.c                         | 37 ++++++++++++++++
 mm/vmscan.c                             |  2 +-
 11 files changed, 121 insertions(+), 114 deletions(-)
---
base-commit: d7be408821acadd7d713d1da16a6742886799114
change-id: 20260531-ch-swap-series-plus-folio-lru-cleanup-d9781c8332dc

Best regards,
-- 
Jianyue Wu <wujianyue000@xxxxxxxxx>