> > On Mon, Jun 09, 2025 at 09:32:20AM +0000, wangtao wrote: > > Are you suggesting adding an ITER_DMABUF type to iov_iter, > > Yes. May I clarify: Do all disk operations require data to pass through memory (reading into memory or writing from memory)? In the block layer, the bio structure uses bio_iov_iter_get_pages to convert iter_type objects into memory-backed bio_vec representations. However, some dmabufs are not memory-based, making page-to-bio_vec conversion impossible. This suggests adding a callback function in dma_buf_ops to handle dmabuf- to-bio_vec conversion. Interestingly, if such a callback exists, the need for a dedicated ITER_DMABUF type might disappear. Would you like to discuss potential implementation tradeoffs here? Regards, Wangtao.
