On Wed, 7 Nov 2018 20:15:36 -0800 "Joel Fernandes (Google)" <joel@xxxxxxxxxxxxxxxxx> wrote: > Android uses ashmem for sharing memory regions. We are looking forward > to migrating all usecases of ashmem to memfd so that we can possibly > remove the ashmem driver in the future from staging while also > benefiting from using memfd and contributing to it. Note staging drivers > are also not ABI and generally can be removed at anytime. > > One of the main usecases Android has is the ability to create a region > and mmap it as writeable, then add protection against making any > "future" writes while keeping the existing already mmap'ed > writeable-region active. This allows us to implement a usecase where > receivers of the shared memory buffer can get a read-only view, while > the sender continues to write to the buffer. > See CursorWindow documentation in Android for more details: > https://developer.android.com/reference/android/database/CursorWindow It appears that the memfd_create and fcntl manpages will require updating. Please attend to this at the appropriate time? Actually, it would help the review process if those updates were available now.