svn commit: r239132 - head/sys/geom

[Jim Harris]

Author: jimharris
Date: Tue Aug  7 20:16:10 2012
New Revision: 239132
URL: http://svn.freebsd.org/changeset/base/239132

Log:
  Clone BIO_ORDERED flag, for disk drivers (namely CAM) that try to
   consume it.
  
  Sponsored by: Intel
  Discussed with: gibbs, scottl

Modified:
  head/sys/geom/geom_io.c

Modified: head/sys/geom/geom_io.c
==============================================================================
--- head/sys/geom/geom_io.c	Tue Aug  7 18:50:33 2012	(r239131)
+++ head/sys/geom/geom_io.c	Tue Aug  7 20:16:10 2012	(r239132)
@@ -177,6 +177,12 @@ g_clone_bio(struct bio *bp)
 	if (bp2 != NULL) {
 		bp2->bio_parent = bp;
 		bp2->bio_cmd = bp->bio_cmd;
+		/*
+		 *  BIO_ORDERED flag may be used by disk drivers to enforce
+		 *  ordering restrictions, so this flag needs to be cloned.
+		 *  Other bio flags are not suitable for cloning.
+		 */
+		bp2->bio_flags = bp->bio_flags & BIO_ORDERED;
 		bp2->bio_length = bp->bio_length;
 		bp2->bio_offset = bp->bio_offset;
 		bp2->bio_data = bp->bio_data;