[src/trunk]: src/sys/dev/pci fix number of maximum segments in the queue allo...

[jdolecek <jdolecek%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/a786fe29a596
branches:  trunk
changeset: 353588:a786fe29a596
user:      jdolecek <jdolecek%NetBSD.org@localhost>
date:      Sat May 13 20:17:42 2017 +0000

description:
fix number of maximum segments in the queue allocation so that
MAXPHYS-sized tranfer fits inside the indirect descriptor; avoids the
!indirect path in virtio_enqueue_reserve() for these transfers,
which runs out of the vq_entries and triggers XS_RESOURCE_SHORTAGE for
bigger number of outstanding tranfers

fixes PR kern/52199 by MB

diffstat:

 sys/dev/pci/vioscsi.c |  6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diffs (27 lines):

diff -r 7beb66cdbc46 -r a786fe29a596 sys/dev/pci/vioscsi.c
--- a/sys/dev/pci/vioscsi.c     Sat May 13 20:13:26 2017 +0000
+++ b/sys/dev/pci/vioscsi.c     Sat May 13 20:17:42 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vioscsi.c,v 1.16 2017/03/25 23:58:35 christos Exp $    */
+/*     $NetBSD: vioscsi.c,v 1.17 2017/05/13 20:17:42 jdolecek Exp $    */
 /*     $OpenBSD: vioscsi.c,v 1.3 2015/03/14 03:38:49 jsg Exp $ */
 
 /*
@@ -18,7 +18,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vioscsi.c,v 1.16 2017/03/25 23:58:35 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vioscsi.c,v 1.17 2017/05/13 20:17:42 jdolecek Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -154,7 +154,7 @@
 
        for(i=0; i < __arraycount(sc->sc_vqs); i++) {
                rv = virtio_alloc_vq(vsc, &sc->sc_vqs[i], i, MAXPHYS,
-                   1 + howmany(MAXPHYS, NBPG),
+                   VIRTIO_SCSI_MIN_SEGMENTS + howmany(MAXPHYS, NBPG),
                    vioscsi_vq_names[i]);
                if (rv) {
                        aprint_error_dev(sc->sc_dev,