On Mon, Jun 27, 2022 at 03:36:22PM +0800, Ming Lei wrote: > Not mention bio_iter, bvec_iter has been 32 bytes, which is too big to > hold in per-io data structure. With this patch, 8bytes is enough > to rewind one bio if the end sector is fixed.
And with rewind, you're making an assumption about the state the iterator is going to be in when the IO has completed. What if the iterator was never advanced? So say you check for that by saving some other part of the iterator - but that may have legitimately changed too, if the bio was redirected (bi_sector changes) or trimmed (bi_size changes) I still think this is an inherently buggy interface, the way it's being proposed to be used. -- dm-devel mailing list dm-devel@redhat.com https://listman.redhat.com/mailman/listinfo/dm-devel
