fs/proc/task_mmu: indicate PM_FILE for PMD-mapped file THP

Patch series "fs/proc: move page_mapcount() to fs/proc/internal.h".

With all other page_mapcount() users in the tree gone, move
page_mapcount() to fs/proc/internal.h, rename it and extend the
documentation to prevent future (ab)use.

... of course, I find some issues while working on that code that I sort
first ;)

We'll now only end up calling page_mapcount() [now
folio_precise_page_mapcount()] on pages mapped via present page table
entries.  Except for /proc/kpagecount, that still does questionable
things, but we'll leave that legacy interface as is for now.

Did a quick sanity check.  Likely we would want some better selfestest for
/proc/$/pagemap + smaps.  I'll see if I can find some time to write some
more.


This patch (of 6):

Looks like we never taught pagemap_pmd_range() about the existence of
PMD-mapped file THPs.  Seems to date back to the times when we first added
support for non-anon THPs in the form of shmem THP.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: David Hildenbrand <[email protected]>
Fixes: 800d8c63b2e9 ("shmem: add huge pages support")
Acked-by: Kirill A. Shutemov <[email protected]>
Reviewed-by: Lance Yang <[email protected]>
Reviewed-by: Oscar Salvador <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions