On 2/4/21 1:04 PM, Axel Rasmussen wrote: > On Thu, Feb 4, 2021 at 11:57 AM Randy Dunlap <rdunlap@xxxxxxxxxxxxx> wrote: >> >> Hi Axel- >> >> one typo found: >> >> On 2/4/21 10:34 AM, Axel Rasmussen wrote: >>> Reword / reorganize things a little bit into "lists", so new features / >>> modes / ioctls can sort of just be appended. >> >> Good plan. >> >>> >>> Signed-off-by: Axel Rasmussen <axelrasmussen@xxxxxxxxxx> >>> --- >>> Documentation/admin-guide/mm/userfaultfd.rst | 107 ++++++++++++------- >>> 1 file changed, 66 insertions(+), 41 deletions(-) >>> >>> diff --git a/Documentation/admin-guide/mm/userfaultfd.rst b/Documentation/admin-guide/mm/userfaultfd.rst >>> index 65eefa66c0ba..cfd3daf59d0e 100644 >>> --- a/Documentation/admin-guide/mm/userfaultfd.rst >>> +++ b/Documentation/admin-guide/mm/userfaultfd.rst >> >> [snip] >> >>> - >>> -Once the ``userfaultfd`` has been enabled the ``UFFDIO_REGISTER`` ioctl should >>> -be invoked (if present in the returned ``uffdio_api.ioctls`` bitmask) to >>> -register a memory range in the ``userfaultfd`` by setting the >>> +events, except page fault notifications, may be generated: >>> + >>> +- The ``UFFD_FEATURE_EVENT_*`` flags indicate that various other events >>> + other than page faults are supported. These events are described in more >>> + detail below in the `Non-cooperative userfaultfd`_ section. >>> + >>> +- ``UFFD_FEATURE_MISSING_HUGETLBFS`` and ``UFFD_FEATURE_MISSING_SHMEM`` >>> + indicate that the kernel supports ``UFFDIO_REGISTER_MODE_MISSING`` >>> + registrations for hugetlbfs and shared memory (covering all shmem APIs, >>> + i.e. tmpfs, ``IPCSHM``, ``/dev/zero``, ``MAP_SHARED``, ``memfd_create``, >>> + etc) virtual memory areas, respectively. >>> + >>> +- ``UFFD_FEATURE_MINOR_HUGETLBFS`` indicates that the kernel supports >>> + ``UFFDIO_REGISTER_MODE_MINOR`` registration for hugetlbfs virtual memory >>> + areas. >>> + >>> +The userland application should set the feature flags it intends to use >> >> (ah, userspace has moved to userland temporarily. :) > > For better or worse, other parts of the document I'm not touching also > use this wording. Maybe we should s/userland/userspace/g, but perhaps > better done as a separate commit to keep this diff focused? > Anecdotally, the use of "userland" doesn't seem to be completely > unprecedented (e.g. grep -r "userland" | wc -l yields 566 matches in > the kernel tree). > > I don't have strong feelings, and I was amused by picturing some > Shire-esque countryside with a friendly sign that reads: ~userland > welcomes you~. :) I'm OK with not changing it. Up to you. -- ~Randy
