From 042e966a70789bd3ed450fa4f57016129a34672e Mon Sep 17 00:00:00 2001
From: Thomas Huth <thuth@redhat.com>
Date: Fri, 8 Jul 2022 12:29:50 +0200
Subject: [PATCH 37/37] pc-bios/s390-ccw/virtio-blkdev: Request the right
 feature bits

RH-Author: Thomas Huth <thuth@redhat.com>
RH-MergeRequest: 198: pc-bios/s390-ccw: Fix boot from disks with 4k sectors that do not have the typical DASD geometry
RH-Commit: [9/9] f04835423d648b04f2187ef9890f2d1689e2b57e
RH-Bugzilla: 2098076
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: David Hildenbrand <david@redhat.com>
RH-Acked-by: Cornelia Huck <cohuck@redhat.com>

Bugzilla: http://bugzilla.redhat.com/2098076

commit 9125a314cca4a1838b09305a87d8efb98f80ab67
Author: Thomas Huth <thuth@redhat.com>
Date:   Mon Jul 4 13:19:01 2022 +0200

    pc-bios/s390-ccw/virtio-blkdev: Request the right feature bits

    The virtio-blk code uses the block size and geometry fields in the
    config area. According to the virtio-spec, these have to be negotiated
    with the right feature bits during initialization, otherwise they
    might not be available. QEMU is so far very forgiving and always
    provides them, but we should not rely on this behavior, so let's
    better request them properly via the VIRTIO_BLK_F_GEOMETRY and
    VIRTIO_BLK_F_BLK_SIZE feature bits.

    Message-Id: <20220704111903.62400-11-thuth@redhat.com>
    Signed-off-by: Thomas Huth <thuth@redhat.com>

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 pc-bios/s390-ccw/virtio-blkdev.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pc-bios/s390-ccw/virtio-blkdev.c b/pc-bios/s390-ccw/virtio-blkdev.c
index c175b66a47..8271c47296 100644
--- a/pc-bios/s390-ccw/virtio-blkdev.c
+++ b/pc-bios/s390-ccw/virtio-blkdev.c
@@ -13,6 +13,9 @@
 #include "virtio.h"
 #include "virtio-scsi.h"
 
+#define VIRTIO_BLK_F_GEOMETRY   (1 << 4)
+#define VIRTIO_BLK_F_BLK_SIZE   (1 << 6)
+
 static int virtio_blk_read_many(VDev *vdev, ulong sector, void *load_addr,
                                 int sec_num)
 {
@@ -223,6 +226,7 @@ int virtio_blk_setup_device(SubChannelId schid)
 {
     VDev *vdev = virtio_get_device();
 
+    vdev->guest_features[0] = VIRTIO_BLK_F_GEOMETRY | VIRTIO_BLK_F_BLK_SIZE;
     vdev->schid = schid;
     virtio_setup_ccw(vdev);
 
-- 
2.35.3