On Tue, Dec 18, 2018 at 11:16:08PM -0800, Linus Torvalds wrote: > On Tue, Dec 18, 2018, 23:11 Christoph Hellwig <hch@xxxxxxxxxxxxx wrote: > > > > > I think the fd would have to be on the same fs for this interface to > > make sense. But it could be an O_TMPFILE one. And given that ext4 > > already supports a variant of swapext this interface should also work > > with the existing ext4 on disk format. > > > > Why is the merkle tree not just an xattr of the file? Because it is too large for our awkward xattrs interface..