On 8/30/18 11:36 AM, Christoph Hellwig wrote: > On Thu, Aug 30, 2018 at 11:31:40AM -0500, Eric Sandeen wrote: >> That's no reason to uniquely disallow it for reflinked files, though; >> the problem is universal. It's true for fiemap as well. So I'm not sure >> that's an argument against the patch? > > fiemap at least tells you an extent is shared, bmap does not. yes, so bmap is clearly the wrong interface to use if you want to write directly to a file's blocks. But if you know enough to check the fiemap shared flag, you know enough to not use fibmap for that purpose... -Eric
