[PATCH 0/6] userfaultfd: decouple uffd mode from VMA flags

["Mike Rapoport (Microsoft)" <rppt@kernel.org>]

Currently userfault related VMA flags have multiple meanings:
* identify VMAs that are registered with userfaultfd
* and also how exactly VMA is registered with uffd
* and also communicate kind of user fault between the page fault handler
  and handle_userfault()

Introduce an enum for user fault reasons and move the registration mode
into per VMA vm_uffd_state structure today known as vm_userfaultfd_ctx.

---
Mike Rapoport (Microsoft) (6):
      mm/gup: move gup_can_follow_protnone() to gup.c
      userfaultfd: constify VMA parameter of userfaultfd_*() helpers
      userfaultfd: use userfaultfd_*() helpers instead of open coded flag tests
      userfaultfd: rename vm_userfaultfd_ctx to vm_uffd_state
      userfaultfd: decouple fault reason from VMA flags
      userfaultfd: collapse VM_UFFD_{MISSING,WP,MINOR,RWP} into single VM_UFFD

 Documentation/mm/process_addrs.rst |   4 +-
 fs/proc/task_mmu.c                 |  18 +--
 include/linux/mm.h                 | 105 +++--------------
 include/linux/mm_types.h           |  11 +-
 include/linux/pgtable.h            |   4 +-
 include/linux/userfaultfd_k.h      | 155 ++++++++++++++-----------
 include/trace/events/mmflags.h     |  17 +--
 include/uapi/linux/userfaultfd.h   |   6 +-
 mm/gup.c                           |  39 +++++++
 mm/huge_memory.c                   |   6 +-
 mm/hugetlb.c                       |  12 +-
 mm/khugepaged.c                    |   2 +-
 mm/memory.c                        |  16 +--
 mm/mprotect.c                      |   2 +-
 mm/mremap.c                        |   4 +-
 mm/shmem.c                         |   6 +-
 mm/userfaultfd.c                   | 225 +++++++++++++++++++------------------
 mm/vma.c                           |   4 +-
 mm/vma.h                           |   6 +-
 mm/vma_init.c                      |   4 +-
 tools/testing/vma/include/dup.h    |  20 ++--
 tools/testing/vma/include/stubs.h  |   6 +-
 22 files changed, 323 insertions(+), 349 deletions(-)
---
base-commit: 4b2ae13f3393ef4b4bce0021e8762790354f369f
change-id: 20260823-uffd-vm-flags-v1-ee3e131b381d

--
Sincerely yours,
Mike.