[PATCH v6 0/6] userfaultfd: convert userfaultfd functions to use folios

[Peng Zhang <zhangpeng362@huawei.com>]

From: ZhangPeng <zhangpeng362@huawei.com>

This patch series converts several userfaultfd functions to use folios.

Change log:

v5->v6:
- Remove VM_BUG_ON_FOLIO from mfill_atomic_pte_copy() per Mike Kravetz.
  (patch 1)
- Keep flush_dcache_page() in copy_folio_from_user() to not change the
  behavior of the function, suggested by Vishal Moola. (patch 3)
- Rename copy_user_folio() to copy_user_large_folio(), suggested by Mike
  Kravetz. (patch 5)
- Add RB from Mike Kravetz. (patch 1-4,6)

v4->v5:
- Update commit description and change page_kaddr to kaddr, suggested by
  Matthew Wilcox. (patch 1,6)
- Remove pages_per_huge_page from copy_user_folio(), suggested by
  Matthew Wilcox. (patch 5)
- Add RB from Sidhartha Kumar. (patch 1,3,4)

v3->v4:
- Rebase onto mm-unstable per Andrew Morton. Update commit description
  because some function names are changed. (patch 1,4,6)

v2->v3:
- Split patch 2 into three patches, suggested by Mike Kravetz. (patch
  2-4)
- Add a new patch to convert copy_user_huge_page to copy_user_folio,
  suggested by Mike Kravetz. (patch 5)
- Fix two uninitialized bugs, thanks to Dan Carpenter. (patch 6)
- Do some indenting cleanups.

v1->v2:
Modified patch 2, suggested by Matthew Wilcox:
- Rename copy_large_folio_from_user() to copy_folio_from_user().
- Delete the inner_folio.
- kmap() and kmap_atomic() are converted to kmap_local_page(). Use
  pagefault_disable() to ensure that a deadlock will not occur.
- flush_dcache_folio() is placed outside the loop.

ZhangPeng (6):
  userfaultfd: convert mfill_atomic_pte_copy() to use a folio
  userfaultfd: use kmap_local_page() in copy_huge_page_from_user()
  userfaultfd: convert copy_huge_page_from_user() to
    copy_folio_from_user()
  userfaultfd: convert mfill_atomic_hugetlb() to use a folio
  mm: convert copy_user_huge_page() to copy_user_large_folio()
  userfaultfd: convert mfill_atomic() to use a folio

 include/linux/hugetlb.h  |  4 +-
 include/linux/mm.h       | 14 +++----
 include/linux/shmem_fs.h |  4 +-
 mm/hugetlb.c             | 40 +++++++++---------
 mm/memory.c              | 61 +++++++++++++---------------
 mm/shmem.c               | 16 ++++----
 mm/userfaultfd.c         | 88 ++++++++++++++++++++--------------------
 7 files changed, 109 insertions(+), 118 deletions(-)

-- 
2.25.1