svn commit: r348650 - stable/12/sys/dev/xdma

[Ruslan Bukin]

Author: br
Date: Tue Jun  4 17:42:47 2019
New Revision: 348650
URL: https://svnweb.freebsd.org/changeset/base/348650

Log:
  MFC r348364:
  
  Don't copy the data from bounce buffer back to the mbuf if channel does
  not use bounce buffering.
  
  Sponsored by:	DARPA, AFRL

Modified:
  stable/12/sys/dev/xdma/xdma_sg.c

Modified: stable/12/sys/dev/xdma/xdma_sg.c
==============================================================================
--- stable/12/sys/dev/xdma/xdma_sg.c	Tue Jun  4 17:39:46 2019	(r348649)
+++ stable/12/sys/dev/xdma/xdma_sg.c	Tue Jun  4 17:42:47 2019	(r348650)
@@ -345,7 +345,8 @@ xchan_seg_done(xdma_channel_t *xchan,
 				    BUS_DMASYNC_POSTREAD);
 			bus_dmamap_unload(xchan->dma_tag_bufs, b->map);
 		} else {
-			if (xr->req_type == XR_TYPE_MBUF &&
+			if ((xchan->caps & XCHAN_CAP_NOBUFS) == 0 &&
+			    xr->req_type == XR_TYPE_MBUF &&
 			    xr->direction == XDMA_DEV_TO_MEM)
 				m_copyback(xr->m, 0, st->transferred,
 				    (void *)xr->buf.vaddr);