On Tue, 2015-02-03 at 11:35 +0200, Michael S. Tsirkin wrote: > On Tue, Feb 03, 2015 at 06:29:54AM +0000, Nicholas A. Bellinger wrote: > > From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> > > > > Hi MST, Paolo, Al & Co, > > > > Here is -v3 for adding vhost/scsi ANY_LAYOUT + VERSION_1 host feature > > bit support. > > > > It adds a new vhost_virtqueue ->handle_kick() callback to determine the > > start of protection and data payloads iovecs past starting virtio-scsi > > request and response headers, based upon data_direction using iov_iter > > primitives. > > > > It assumes request/CDB and response/sense_buffer headers may span more > > than a single iovec using mm/iov_iter.c logic. > > > > It also allows virtio-scsi headers + T10_PI + Data SGL payloads to span > > the same iovec when pinning user-space memory via get_user_pages_fast() > > code. (Not tested yet) > > > > Based upon Al & HCH's feedback, the patch series has been converted to > > use copy_*_iter() for virtio-scsi header copy. Also, patch #4 has been > > updated to use iov_iter_npages() for sgl_count, and patch #5 updated to > > use iov_iter_advance() for calculating prot_bytes offset to the start > > of data_iter. > > > > v3 changelog: > > - Convert memcpy_toiovecend -> copy_to_iter usage > > - Update vhost_scsi_mapal + friends to use iov_iter > > - Move iov_iter sanity checks into vhost_scsi_calc_sgls > > - Convert vhost_scsi_calc_sgls() to iov_iter_npages() > > - Convert to vhost_scsi_handle_vqal to copy_from_iter usage > > - Update vhost_scsi_handle_vqal comments for iov_iter usage > > - Convert prot_bytes offset to use iov_iter_advance > > - Drop max_niov usage in vhost_scsi_handle_vqal > > - Drop vhost_skip_iovec_bytes in favour of iov_iter > > > > Note the one part that has been left unchanged is vhost_scsi_map_to_sgl() > > into get_user_pages_fast(), for which existing iov_iter_get_pages() code > > will need to allow for a callback to perform the associated scatterlists > > setup from **pages for protection + data payloads. > > I'm not sure it has to be a callback: maybe just add > struct scatterlist *sg parameter and use it if set. > Al, any preference on how this should work..? --nab -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
