migration: Remove load_state_old and minimum_version_id_old

There are no longer any VMStateDescription structs in the tree which
use the load_state_old support for custom handling of incoming
migration from very old QEMU.  Remove the mechanism entirely.

This includes removing one stray useless setting of
minimum_version_id_old in a VMStateDescription with no load_state_old
function, which crept in after the global weeding-out of them in
commit 17e313406126.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20220215175705.3846411-1-peter.maydell@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Francisco Iglesias <francisco.iglesias@xilinx.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

4 files changed, 3 insertions, 18 deletions

diff --git a/docs/devel/migration.rst b/docs/devel/migration.rst
index 2401253482..3e9656d8e0 100644
--- a/docs/devel/migration.rst
+++ b/docs/devel/migration.rst
@@ -389,19 +389,13 @@ Each version is associated with a series of fields saved.  The ``save_state`` al
 the state as the newer version.  But ``load_state`` sometimes is able to
 load state from an older version.
 
-You can see that there are several version fields:
+You can see that there are two version fields:
 
 - ``version_id``: the maximum version_id supported by VMState for that device.
 - ``minimum_version_id``: the minimum version_id that VMState is able to understand
   for that device.
-- ``minimum_version_id_old``: For devices that were not able to port to vmstate, we can
-  assign a function that knows how to read this old state. This field is
-  ignored if there is no ``load_state_old`` handler.
-
-VMState is able to read versions from minimum_version_id to
-version_id.  And the function ``load_state_old()`` (if present) is able to
-load state from minimum_version_id_old to minimum_version_id.  This
-function is deprecated and will be removed when no more users are left.
+
+VMState is able to read versions from minimum_version_id to version_id.
 
 There are *_V* forms of many ``VMSTATE_`` macros to load fields for version dependent fields,
 e.g.
diff --git a/hw/ssi/xlnx-versal-ospi.c b/hw/ssi/xlnx-versal-ospi.c
index 7ecd148fdf..c762e0b367 100644
--- a/hw/ssi/xlnx-versal-ospi.c
+++ b/hw/ssi/xlnx-versal-ospi.c
@@ -1800,7 +1800,6 @@ static const VMStateDescription vmstate_xlnx_versal_ospi = {
     .name = TYPE_XILINX_VERSAL_OSPI,
     .version_id = 1,
     .minimum_version_id = 1,
-    .minimum_version_id_old = 1,
     .fields = (VMStateField[]) {
         VMSTATE_FIFO8(rx_fifo, XlnxVersalOspi),
         VMSTATE_FIFO8(tx_fifo, XlnxVersalOspi),
diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h
index 017c03675c..ad24aa1934 100644
--- a/include/migration/vmstate.h
+++ b/include/migration/vmstate.h
@@ -181,9 +181,7 @@ struct VMStateDescription {
     int unmigratable;
     int version_id;
     int minimum_version_id;
-    int minimum_version_id_old;
     MigrationPriority priority;
-    LoadStateHandler *load_state_old;
     int (*pre_load)(void *opaque);
     int (*post_load)(void *opaque, int version_id);
     int (*pre_save)(void *opaque);
diff --git a/migration/vmstate.c b/migration/vmstate.c
index 05f87cdddc..36ae8b9e19 100644
--- a/migration/vmstate.c
+++ b/migration/vmstate.c
@@ -90,12 +90,6 @@ int vmstate_load_state(QEMUFile *f, const VMStateDescription *vmsd,
         return -EINVAL;
     }
     if  (version_id < vmsd->minimum_version_id) {
-        if (vmsd->load_state_old &&
-            version_id >= vmsd->minimum_version_id_old) {
-            ret = vmsd->load_state_old(f, opaque, version_id);
-            trace_vmstate_load_state_end(vmsd->name, "old path", ret);
-            return ret;
-        }
         error_report("%s: incoming version_id %d is too old "
                      "for local minimum version_id  %d",
                      vmsd->name, version_id, vmsd->minimum_version_id);