On Fri, Jul 10, 2020 at 12:35:43AM +0530, Kanchan Joshi wrote: > Append required special treatment (conversion for sector to bytes) for > io_uring. > And we were planning a user-space wrapper to abstract that. > > But good part (as it seems now) was: append result went along with cflags at > virtually no additional cost. And uring code changes became super > clean/minimal > with further revisions. > While indirect-offset requires doing allocation/mgmt in application, > io-uring submission > and in completion path (which seems trickier), and those CQE flags > still get written > user-space and serve no purpose for append-write.
I have to say that storing the results in the CQE generally make so much more sense. I wonder if we need a per-fd "large CGE" flag that adds two extra u64s to the CQE, and some ops just require this version.