The storage keys are part of the machine memory.

Introduce the TYPE_DUMP_SKEYS_INTERFACE type,
allowing machine using storage keys to dump them
when a DumpSKeysInterface::qmp_dump_skeys() callback
is provided.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 include/hw/s390x/storage-keys.h | 15 +++++++++++++++
 hw/s390x/s390-skeys.c           |  5 +++++
 2 files changed, 20 insertions(+)

diff --git a/include/hw/s390x/storage-keys.h b/include/hw/s390x/storage-keys.h
index 408d2815d4d..fb766d4631b 100644
--- a/include/hw/s390x/storage-keys.h
+++ b/include/hw/s390x/storage-keys.h
@@ -125,4 +125,19 @@ S390SKeysState *s390_get_skeys_device(void);
 void hmp_dump_skeys(Monitor *mon, const QDict *qdict);
 void hmp_info_skeys(Monitor *mon, const QDict *qdict);
 
+#define TYPE_DUMP_SKEYS_INTERFACE "dump-skeys-interface"
+
+typedef struct DumpSKeysInterface DumpSKeysInterface;
+DECLARE_CLASS_CHECKERS(DumpSKeysInterface, DUMP_SKEYS_INTERFACE,
+                       TYPE_DUMP_SKEYS_INTERFACE)
+
+struct DumpSKeysInterface {
+    InterfaceClass parent_class;
+
+    /**
+     * @qmp_dump_skeys: Callback to dump guest's storage keys to @filename.
+     */
+    void (*qmp_dump_skeys)(const char *filename, Error **errp);
+};
+
 #endif /* S390_STORAGE_KEYS_H */
diff --git a/hw/s390x/s390-skeys.c b/hw/s390x/s390-skeys.c
index d50e71b927a..0d3d4f74b4c 100644
--- a/hw/s390x/s390-skeys.c
+++ b/hw/s390x/s390-skeys.c
@@ -474,6 +474,11 @@ static void s390_skeys_class_init(ObjectClass *oc, void *data)
 }
 
 static const TypeInfo s390_skeys_types[] = {
+    {
+        .name           = TYPE_DUMP_SKEYS_INTERFACE,
+        .parent         = TYPE_INTERFACE,
+        .class_size     = sizeof(DumpSKeysInterface),
+    },
     {
         .name           = TYPE_S390_SKEYS,
         .parent         = TYPE_DEVICE,
-- 
2.47.1

On Mon, 2025-03-10 at 16:14 +0100, Philippe Mathieu-Daudé wrote:
> The storage keys are part of the machine memory.
> 
> Introduce the TYPE_DUMP_SKEYS_INTERFACE type,
> allowing machine using storage keys to dump them
> when a DumpSKeysInterface::qmp_dump_skeys() callback
> is provided.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>  include/hw/s390x/storage-keys.h | 15 +++++++++++++++
>  hw/s390x/s390-skeys.c           |  5 +++++
>  2 files changed, 20 insertions(+)

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

On 10/03/2025 16.14, Philippe Mathieu-Daudé wrote:
> The storage keys are part of the machine memory.
> 
> Introduce the TYPE_DUMP_SKEYS_INTERFACE type,
> allowing machine using storage keys to dump them
> when a DumpSKeysInterface::qmp_dump_skeys() callback
> is provided.
> 
> Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
> ---
>   include/hw/s390x/storage-keys.h | 15 +++++++++++++++
>   hw/s390x/s390-skeys.c           |  5 +++++
>   2 files changed, 20 insertions(+)

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