Re: [RFC PATCH 0/7] xfs: add reflink & dedupe support for fsdax.

Christoph Hellwig
2019-10-09T06:31:47Z

Btw, I just had a chat with Dan last week on this. And he pointed out
that while this series deals with the read/write path issues of
reflink on DAX it doesn't deal with the mmap side issue that
page->mapping and page->index can point back to exactly one file.

I think we want a few xfstests that reflink a file and then use the
different links using mmap, as that should blow up pretty reliably.