[PATCH v4 00/16] Prepare slab for memdescs

["Matthew Wilcox (Oracle)" <willy@infradead.org>]

When we separate struct folio, struct page and struct slab from each
other, converting to folios then to slabs will be nonsense.  It made
sense under the 'folio is just a head page' interpretation, but with
full separation, page_folio() will return NULL for a page which belongs
to a slab.

This patch series removes almost all mentions of folio from slab.
There are a few folio_test_slab() invocations left around the tree that
I haven't decided how to handle yet.  We're not yet quite at the point
of separately allocating struct slab, but that's what I'll be working
on next.

v4:
 - Rebased on next-20251110 + a couple of fixes
 - Fixed compilation warnings when CONFIG_MEMCG not set
 - Picked up R-b tags from Harry (thanks!)
 - Restored the order of slab vs large_kmalloc tests (Vlastimil)
 - Removed setting of LargeKmalloc on tail pages (Vlastimil)
 - Restored handling of non-slab, non-kmalloc checks in
   check_heap_object() (me)

Matthew Wilcox (Oracle) (16):
  slab: Reimplement page_slab()
  slab: Remove folio references from __ksize()
  slab: Remove folio references in memcg_slab_post_charge()
  slab: Remove folio references in slab alloc/free
  slab: Remove folio references from ___kmalloc_large_node()
  slab: Remove folio references from free_large_kmalloc()
  slab: Remove folio references from kvfree_rcu_cb()
  slab: Remove folio references from kfree()
  slab: Remove folio references from __do_krealloc()
  slab: Remove folio references from build_detached_freelist()
  slab: Remove folio references from kfree_rcu_sheaf()
  slab: Remove folio references from kfree_nolock()
  usercopy: Remove folio references from check_heap_object()
  memcg: Convert mem_cgroup_from_obj_folio() to
    mem_cgroup_from_obj_slab()
  kasan: Remove references to folio in __kasan_mempool_poison_object()
  slab: Remove references to folios from virt_to_slab()

 include/linux/page-flags.h |  16 +----
 mm/kasan/common.c          |  12 ++--
 mm/kfence/core.c           |  14 ++--
 mm/memcontrol.c            |  36 ++++------
 mm/slab.h                  |  58 ++++++++--------
 mm/slab_common.c           |  29 ++++----
 mm/slub.c                  | 137 +++++++++++++++++++------------------
 mm/usercopy.c              |  24 ++++---
 8 files changed, 153 insertions(+), 173 deletions(-)

-- 
2.47.2