On Tue, Jul 27, 2021 at 08:31:38AM +0200, Christoph Hellwig wrote: > On Mon, Jul 26, 2021 at 09:39:22AM -0700, Darrick J. Wong wrote: > > The documentation needs to be much more explicit about the fact that you > > cannot "break;" your way out of an iomap_iter loop. I think the comment > > should be rewritten along these lines: > > > > "Iterate over filesystem-provided space mappings for the provided file > > range. This function handles cleanup of resources acquired for > > iteration when the filesystem indicates there are no more space > > mappings, which means that this function must be called in a loop that > > continues as long it returns a positive value. If 0 or a negative value > > is returned, the caller must not return to the loop body. Within a loop > > body, there are two ways to break out of the loop body: leave > > @iter.processed unchanged, or set it to the usual negative errno." > > > > Hm. > > Yes, I'll update the documentation. Ok, thanks! > > Clunky, for sure, but at least we still get to use break as the language > > designers intended. > > I can't see any advantage there over just proper documentation. If you > are totally attached to a working break we might have to come up with > a nasty for_each macro that ensures we have a final iomap_apply, but I > doubt it is worth the effort. I was pushing the explicit _break() function as a means to avoid an even fuglier loop macro. --D
