[PATCH 0/6] mm: vma flag tweaks

[Lorenzo Stoakes (Oracle)]

The ongoing work around introducing non-system word VMA flags has
introduced a number of helper functions and macros to make life easier when
working with these flags and to make conversions from the legacy use of
VM_xxx flags more straightforward.

This series improves these to reduce confusion as to what they do and to
improve consistency and readability.

Firstly the series renames vma_flags_test() to vma_flags_test_any() to make
it abundantly clear that this function tests whether any of the flags are
set (as opposed to vma_flags_test_all()).

It then renames vma_desc_test_flags() to vma_desc_test_any() for the same
reason. Note that we drop the 'flags' suffix here, as
vma_desc_test_any_flags() would be cumbersome and 'test' implies a flag
test.

Similarly, we rename vma_test_all_flags() to vma_test_all() for
consistency.

Next, we have a couple of instances (erofs, zonefs) where we are now
testing for vma_desc_test_any(desc, VMA_SHARED_BIT) &&
vma_desc_test_any(desc, VMA_MAYWRITE_BIT).

This is silly, so this series introduces vma_desc_test_all() so these
callers can instead invoke vma_desc_test_all(desc, VMA_SHARED_BIT,
VMA_MAYWRITE_BIT).

We then observe that quite a few instances of vma_flags_test_any() and
vma_desc_test_any() are in fact only testing against a single flag.

Using the _any() variant here is just confusing - 'any' of single item
reads strangely and is liable to cause confusion.

So in these instances the series reintroduces vma_flags_test() and
vma_desc_test() as helpers which test against a single flag.

The fact that vma_flags_t is a struct and that vma_flag_t utilises sparse
to avoid confusion with vm_flags_t makes it impossible for a user to misuse
these helpers without it getting flagged somewhere.

The series also updates __mk_vma_flags() and functions invoked by it to
explicitly mark them always inline to match expectation and to be
consistent with other VMA flag helpers.

It also renames vma_flag_set() to vma_flags_set_flag() (a function only
used by __mk_vma_flags()) to be consistent with other VMA flag helpers.

Finally it updates the VMA tests for each of these changes, and introduces
explicit tests for vma_flags_test() and vma_desc_test() to assert that they
behave as expected.

Lorenzo Stoakes (Oracle) (6):
  mm: rename VMA flag helpers to be more readable
  mm: add vma_desc_test_all() and use it
  mm: always inline __mk_vma_flags() and invoked functions
  mm: reintroduce vma_flags_test() as a singular flag test
  mm: reintroduce vma_desc_test() as a singular flag test
  tools/testing/vma: add test for vma_flags_test(), vma_desc_test()

 drivers/char/mem.c                 |   2 +-
 drivers/dax/device.c               |   2 +-
 fs/erofs/data.c                    |   3 +-
 fs/hugetlbfs/inode.c               |   2 +-
 fs/ntfs3/file.c                    |   2 +-
 fs/resctrl/pseudo_lock.c           |   2 +-
 fs/zonefs/file.c                   |   3 +-
 include/linux/dax.h                |   4 +-
 include/linux/hugetlb_inline.h     |   2 +-
 include/linux/mm.h                 | 100 +++++++++++++++++++++--------
 include/linux/mm_types.h           |   2 +-
 mm/hugetlb.c                       |  12 ++--
 mm/memory.c                        |   2 +-
 mm/secretmem.c                     |   2 +-
 tools/testing/vma/include/custom.h |   5 +-
 tools/testing/vma/include/dup.h    |  48 ++++++++++----
 tools/testing/vma/tests/vma.c      |  58 +++++++++++++----
 17 files changed, 177 insertions(+), 74 deletions(-)

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2.53.0