From f07e4629a7c58407f903810a038660c88c6a6315 Mon Sep 17 00:00:00 2001

From: Thomas Huth <thuth@redhat.com>

Date: Fri, 8 Jul 2022 20:49:01 +0200

Subject: [PATCH 08/17] pc-bios/s390-ccw/virtio-blkdev: Simplify/fix

 virtio_ipl_disk_is_valid()

RH-Author: Thomas Huth <thuth@redhat.com>

RH-MergeRequest: 106: pc-bios/s390-ccw: Fix boot from disks with 4k sectors that do not have the typical DASD geometry

RH-Commit: [3/10] fb06830a3e50d9da3d84913b50bb227865cc44b3 (thuth/qemu-kvm-cs9)

RH-Bugzilla: 2098077

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/2098077

commit bbf615f7b707f009ef8e757d170902ad33b90644

Author: Thomas Huth <thuth@redhat.com>

Date:   Mon Jul 4 13:18:55 2022 +0200

    pc-bios/s390-ccw/virtio-blkdev: Simplify/fix virtio_ipl_disk_is_valid()

    The s390-ccw bios fails to boot if the boot disk is a virtio-blk

    disk with a sector size of 4096. For example:

     dasdfmt -b 4096 -d cdl -y -p -M quick /dev/dasdX

     fdasd -a /dev/dasdX

     install a guest onto /dev/dasdX1 using virtio-blk

     qemu-system-s390x -nographic -hda /dev/dasdX1

    The bios then bails out with:

     ! Cannot read block 0 !

    Looking at virtio_ipl_disk_is_valid() and especially the function

    virtio_disk_is_scsi(), it does not really make sense that we expect

    only such a limited disk geometry (like a block size of 512) for

    our boot disks. Let's relax the check and allow everything that

    remotely looks like a sane disk.

    Message-Id: <20220704111903.62400-5-thuth@redhat.com>

    Reviewed-by: Eric Farman <farman@linux.ibm.com>

    Signed-off-by: Thomas Huth <thuth@redhat.com>

Signed-off-by: Thomas Huth <thuth@redhat.com>

---

 pc-bios/s390-ccw/virtio-blkdev.c | 41 ++++++--------------------------

 pc-bios/s390-ccw/virtio.h        |  2 --

 2 files changed, 7 insertions(+), 36 deletions(-)

diff --git a/pc-bios/s390-ccw/virtio-blkdev.c b/pc-bios/s390-ccw/virtio-blkdev.c

index 6483307630..7e13155589 100644

--- a/pc-bios/s390-ccw/virtio-blkdev.c

+++ b/pc-bios/s390-ccw/virtio-blkdev.c

@@ -166,46 +166,19 @@ void virtio_assume_eckd(void)

         virtio_eckd_sectors_for_block_size(vdev->config.blk.blk_size);

 }

-bool virtio_disk_is_scsi(void)

-{

-    VDev *vdev = virtio_get_device();

-

-    if (vdev->guessed_disk_nature == VIRTIO_GDN_SCSI) {

-        return true;

-    }

-    switch (vdev->senseid.cu_model) {

-    case VIRTIO_ID_BLOCK:

-        return (vdev->config.blk.geometry.heads == 255)

-            && (vdev->config.blk.geometry.sectors == 63)

-            && (virtio_get_block_size()  == VIRTIO_SCSI_BLOCK_SIZE);

-    case VIRTIO_ID_SCSI:

-        return true;

-    }

-    return false;

-}

-

-bool virtio_disk_is_eckd(void)

+bool virtio_ipl_disk_is_valid(void)

 {

+    int blksize = virtio_get_block_size();

     VDev *vdev = virtio_get_device();

-    const int block_size = virtio_get_block_size();

-    if (vdev->guessed_disk_nature == VIRTIO_GDN_DASD) {

+    if (vdev->guessed_disk_nature == VIRTIO_GDN_SCSI ||

+        vdev->guessed_disk_nature == VIRTIO_GDN_DASD) {

         return true;

     }

-    switch (vdev->senseid.cu_model) {

-    case VIRTIO_ID_BLOCK:

-        return (vdev->config.blk.geometry.heads == 15)

-            && (vdev->config.blk.geometry.sectors ==

-                virtio_eckd_sectors_for_block_size(block_size));

-    case VIRTIO_ID_SCSI:

-        return false;

-    }

-    return false;

-}

-bool virtio_ipl_disk_is_valid(void)

-{

-    return virtio_disk_is_scsi() || virtio_disk_is_eckd();

+    return (vdev->senseid.cu_model == VIRTIO_ID_BLOCK ||

+            vdev->senseid.cu_model == VIRTIO_ID_SCSI) &&

+           blksize >= 512 && blksize <= 4096;

 }

 int virtio_get_block_size(void)

diff --git a/pc-bios/s390-ccw/virtio.h b/pc-bios/s390-ccw/virtio.h

index 9e410bde6f..241730effe 100644

--- a/pc-bios/s390-ccw/virtio.h

+++ b/pc-bios/s390-ccw/virtio.h

@@ -186,8 +186,6 @@ void virtio_assume_scsi(void);

 void virtio_assume_eckd(void);

 void virtio_assume_iso9660(void);

-extern bool virtio_disk_is_scsi(void);

-extern bool virtio_disk_is_eckd(void);

 extern bool virtio_ipl_disk_is_valid(void);

 extern int virtio_get_block_size(void);

 extern uint8_t virtio_get_heads(void);

-- 

2.31.1