On 1/5/23 12:07 PM, Keith Busch wrote: > From: Keith Busch <kbusch@xxxxxxxxxx> > > ITER_UBUF is a more efficient representation when using single vector > buffers, providing small optimizations over ITER_IOVEC. This series > introduces a helper to set these up, and replaces all applicable users > of import_single_range with the new helper. And since there are no > single range users left after this change, the helper is no longer > needed. > > As noted in v1(*), there are some fundamental differences to how io_uring > compares to read/write/readv/writev. There are only the two affected > file_operations, and they already do not work with io_uring due to their > diverging semantics for vectored vs non-vectored read/write. Therefore, > this series having io_uring prefer ubuf iov_iter isn't introducing new > breakage. Pondering how to stage this, both for later upstream but also for testing. Would probably make the best sense to stage 1-5 separately, and then just punt the remaining ones to the appropriate subsystems. And then 12/12 can go in when they have all been applied. -- Jens Axboe
