Hi MST & Paolo, So I'm currently working on vhost-scsi support for ANY_LAYOUT, and wanted to verify some assumptions based upon your earlier emails.. *) When ANY_LAYOUT is negotiated by vhost-scsi, it's expected that virtio-scsi request + response headers will (always..?) be within a single iovec. *) When ANY_LAYOUT is negotiated by vhost-scsi, it's expected that virtio-scsi request + response headers may be (but not always..?) combined with data-out + data-in payloads into a single iovec. *) When ANY_LAYOUT + T10_PI is negotiated by vhost-scsi, it's expected that PI and data payloads for data-out + data-in may be (but not always..?) within the same iovec. Consequently, both headers + PI + data-payloads may also be within a single iovec. *) Is it still safe to use 'out' + 'in' values from vhost_get_vq_desc() in order to determine the data_direction...? If not, what's the preferred way of determining this information for get_user_pages_fast() permission bits and target_submit_cmd_map_sgls()..? Also, what is required on the QEMU side in order to start generating ANY_LAYOUT style iovecs to verify the WIP changes..? I see hw/scsi/virtio-scsi.c has been converted to accept any_layout=1, but AFAICT the changes where only related to code not shared between hw/scsi/vhost-scsi.c. Thank you, --nab -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
