svn commit: r357172 - in head/sys/geom: . stripe

[Konstantin Belousov]

Author: kib
Date: Mon Jan 27 13:15:16 2020
New Revision: 357172
URL: https://svnweb.freebsd.org/changeset/base/357172

Log:
  Fix aggregating geoms for BIO_SPEEDUP.
  
  If the bio was split into several bios going down, completion computes
  bio_completed of the original bio as sum of the bio_completes of the
  splits.  For BIO_SETUP, bio_length means something different than the
  length. it is the requested speedup amount, and is duplicated into the
  splits, which is in fact reasonable, since we cannot know how the
  previous activity was distributed among subordinate geoms.  Obviously,
  the sum of n bio_length is greater than bio_length for n > 1, which
  triggers assert that bio_length >= bio_completed for e.g. geom_stripe
  and geom_raid3.
  
  Fix this by reassigning bio_completed from bio_length for completed
  BIO_SPEEDED, I do not think it really mattters what we return in
  bio_completed.
  
  Reported and tested by:	pho
  Reviewed by:	imp
  MFC after:	1 week
  Differential revision:	https://reviews.freebsd.org/D23380

Modified:
  head/sys/geom/geom_subr.c
  head/sys/geom/stripe/g_stripe.c

Modified: head/sys/geom/geom_subr.c
==============================================================================
--- head/sys/geom/geom_subr.c	Mon Jan 27 13:12:40 2020	(r357171)
+++ head/sys/geom/geom_subr.c	Mon Jan 27 13:15:16 2020	(r357172)
@@ -1134,8 +1134,11 @@ g_std_done(struct bio *bp)
 	bp2->bio_completed += bp->bio_completed;
 	g_destroy_bio(bp);
 	bp2->bio_inbed++;
-	if (bp2->bio_children == bp2->bio_inbed)
+	if (bp2->bio_children == bp2->bio_inbed) {
+		if (bp2->bio_cmd == BIO_SPEEDUP)
+			bp2->bio_completed = bp2->bio_length;
 		g_io_deliver(bp2, bp2->bio_error);
+	}
 }
 
 /* XXX: maybe this is only g_slice_spoiled */

Modified: head/sys/geom/stripe/g_stripe.c
==============================================================================
--- head/sys/geom/stripe/g_stripe.c	Mon Jan 27 13:12:40 2020	(r357171)
+++ head/sys/geom/stripe/g_stripe.c	Mon Jan 27 13:15:16 2020	(r357172)
@@ -298,6 +298,8 @@ g_stripe_done(struct bio *bp)
 		mtx_unlock(&sc->sc_lock);
 		if (pbp->bio_driver1 != NULL)
 			uma_zfree(g_stripe_zone, pbp->bio_driver1);
+		if (bp->bio_cmd == BIO_SPEEDUP)
+			pbp->bio_completed = pbp->bio_length;
 		g_io_deliver(pbp, pbp->bio_error);
 	} else
 		mtx_unlock(&sc->sc_lock);