On Mon, Mar 21, 2016 at 10:52:35AM -0700, Darrick J. Wong wrote:

quoted

I don't really understand the comment.  But I think you'd be much

I don't know of a block device primitive that corresponds to the "default"
mode of fallocate, as documented in the manpage (i.e. mode == 0).  I agree
that the whole thing could be simplified in the manner you point out below.

SCSI allows 'anchoring' blocks, which is pretty similar to a normal
fallocate, but we don't support anchoring blocks in Linux yet.