[PATCH v1 00/29] mm/migration: rework movable_ops page migration (part 1)

David Hildenbrand
2025-06-30T13:00:19Z

Based on mm/mm-new.

In the future, as we decouple "struct page" from "struct folio", pages
that support "non-lru page migration" -- movable_ops page migration
such as memory balloons and zsmalloc -- will no longer be folios. They
will not have ->mapping, ->lru, and likely no refcount and no
page lock. But they will have a type and flags :)

This is the first part (other parts not written yet) of decoupling
movable_ops page migration from folio migration.

In this series, we get rid of the ->mapping usage, and start cleaning up
the code + separating it from folio migration.

Migration core will have to be further reworked to not treat movable_ops
pages like folios. This is the first step into that direction.

Heavily tested with virtio-balloon and lightly tested with zsmalloc
on x86-64. Cross-compile-tested.

RFC -> v1:
* Some smaller fixups + comment changes + subject/description updates
* Added ACKs/RBs (hope I didn't miss any)
* "mm/migrate: move movable_ops page handling out of move_to_new_folio()"
-> Fix goto out; vs goto out_unlock_both;
* "mm: remove __folio_test_movable()"
-> Fix page_has_movable_ops() checking wrong page

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Jerrin Shaji George <jerrin.shaji-george@broadcom.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Cc: "Eugenio Pérez" <eperezma@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: Gregory Price <gourry@gourry.net>
Cc: Ying Huang <ying.huang@linux.alibaba.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Xu Xin <xu.xin16@zte.com.cn>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Rik van Riel <riel@surriel.com>
Cc: Harry Yoo <harry.yoo@oracle.com>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>

David Hildenbrand (29):
mm/balloon_compaction: we cannot have isolated pages in the balloon
list
mm/balloon_compaction: convert balloon_page_delete() to
balloon_page_finalize()
mm/zsmalloc: drop PageIsolated() related VM_BUG_ONs
mm/page_alloc: let page freeing clear any set page type
mm/balloon_compaction: make PageOffline sticky until the page is freed
mm/zsmalloc: make PageZsmalloc() sticky until the page is freed
mm/migrate: rename isolate_movable_page() to
isolate_movable_ops_page()
mm/migrate: rename putback_movable_folio() to
putback_movable_ops_page()
mm/migrate: factor out movable_ops page handling into
migrate_movable_ops_page()
mm/migrate: remove folio_test_movable() and folio_movable_ops()
mm/migrate: move movable_ops page handling out of move_to_new_folio()
mm/zsmalloc: stop using __ClearPageMovable()
mm/balloon_compaction: stop using __ClearPageMovable()
mm/migrate: remove __ClearPageMovable()
mm/migration: remove PageMovable()
mm: rename __PageMovable() to page_has_movable_ops()
mm/page_isolation: drop __folio_test_movable() check for large folios
mm: remove __folio_test_movable()
mm: stop storing migration_ops in page->mapping
mm: convert "movable" flag in page->mapping to a page flag
mm: rename PG_isolated to PG_movable_ops_isolated
mm/page-flags: rename PAGE_MAPPING_MOVABLE to PAGE_MAPPING_ANON_KSM
mm/page-alloc: remove PageMappingFlags()
mm/page-flags: remove folio_mapping_flags()
mm: simplify folio_expected_ref_count()
mm: rename PAGE_MAPPING_* to FOLIO_MAPPING_*
docs/mm: convert from "Non-LRU page migration" to "movable_ops page
migration"
mm/balloon_compaction: "movable_ops" doc updates
mm/balloon_compaction: provide single balloon_page_insert() and
balloon_mapping_gfp_mask()

Documentation/mm/page_migration.rst | 39 ++--
arch/powerpc/platforms/pseries/cmm.c | 2 +-
drivers/misc/vmw_balloon.c | 3 +-
drivers/virtio/virtio_balloon.c | 4 +-
fs/proc/page.c | 4 +-
include/linux/balloon_compaction.h | 90 ++++-----
include/linux/fs.h | 2 +-
include/linux/migrate.h | 46 +----
include/linux/mm.h | 4 +-
include/linux/mm_types.h | 1 -
include/linux/page-flags.h | 104 ++++++----
include/linux/pagemap.h | 2 +-
include/linux/zsmalloc.h | 2 +
mm/balloon_compaction.c | 21 ++-
mm/compaction.c | 44 +----
mm/gup.c | 4 +-
mm/internal.h | 2 +-
mm/ksm.c | 4 +-
mm/memory-failure.c | 4 +-
mm/memory_hotplug.c | 8 +-
mm/migrate.c | 271 ++++++++++++++++-----------
mm/page_alloc.c | 12 +-
mm/page_isolation.c | 12 +-
mm/rmap.c | 16 +-
mm/util.c | 6 +-
mm/vmscan.c | 6 +-
mm/zpdesc.h | 15 +-
mm/zsmalloc.c | 29 ++-
28 files changed, 365 insertions(+), 392 deletions(-)

base-commit: 2e462e10265dcdce546cab85a902b716e2b26d9f
--
2.49.0