s390x/migration: Monitor commands for storage attributes

Add an "info" monitor command to non-destructively inspect the state of
the storage attributes of the guest, and a normal command to toggle
migration mode (useful for debugging).

Signed-off-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

hmp-commands-info.hx

@@ -775,6 +775,22 @@ STEXI
 @item info skeys @var{address}
 @findex skeys
 Display the value of a storage key (s390 only)
+ETEXI
+
+#if defined(TARGET_S390X)
+    {
+        .name       = "cmma",
+        .args_type  = "addr:l,count:l?",
+        .params     = "address [count]",
+        .help       = "Display the values of the CMMA storage attributes for a range of pages",
+        .cmd        = hmp_info_cmma,
+    },
+#endif
+
+STEXI
+@item info cmma @var{address}
+@findex cmma
+Display the values of the CMMA storage attributes for a range of pages (s390 only)
 ETEXI
 
     {

hmp-commands.hx

@@ -1151,6 +1151,22 @@ STEXI
 @item dump-skeys @var{filename}
 @findex dump-skeys
 Save guest storage keys to a file.
+ETEXI
+
+#if defined(TARGET_S390X)
+    {
+        .name       = "migration_mode",
+        .args_type  = "mode:i",
+        .params     = "mode",
+        .help       = "Enables or disables migration mode\n",
+        .cmd        = hmp_migrationmode,
+    },
+#endif
+
+STEXI
+@item migration_mode @var{mode}
+@findex migration_mode
+Enables or disables migration mode.
 ETEXI
 
     {

hw/s390x/s390-stattrib.c

@@ -11,6 +11,7 @@
 
 #include "qemu/osdep.h"
 #include "hw/boards.h"
+#include "qmp-commands.h"
 #include "migration/qemu-file.h"
 #include "migration/register.h"
 #include "hw/s390x/storage-attributes.h"
@@ -26,6 +27,15 @@
 #define STATTR_FLAG_ERROR   0x04ULL
 #define STATTR_FLAG_DONE    0x08ULL
 
+static S390StAttribState *s390_get_stattrib_device(void)
+{
+    S390StAttribState *sas;
+
+    sas = S390_STATTRIB(object_resolve_path_type("", TYPE_S390_STATTRIB, NULL));
+    assert(sas);
+    return sas;
+}
+
 void s390_stattrib_init(void)
 {
     Object *obj;
@@ -42,6 +52,58 @@ void s390_stattrib_init(void)
     qdev_init_nofail(DEVICE(obj));
 }
 
+/* Console commands: */
+
+void hmp_migrationmode(Monitor *mon, const QDict *qdict)
+{
+    S390StAttribState *sas = s390_get_stattrib_device();
+    S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
+    uint64_t what = qdict_get_int(qdict, "mode");
+    int r;
+
+    r = sac->set_migrationmode(sas, what);
+    if (r < 0) {
+        monitor_printf(mon, "Error: %s", strerror(-r));
+    }
+}
+
+void hmp_info_cmma(Monitor *mon, const QDict *qdict)
+{
+    S390StAttribState *sas = s390_get_stattrib_device();
+    S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
+    uint64_t addr = qdict_get_int(qdict, "addr");
+    uint64_t buflen = qdict_get_try_int(qdict, "count", 8);
+    uint8_t *vals;
+    int cx, len;
+
+    vals = g_try_malloc(buflen);
+    if (!vals) {
+        monitor_printf(mon, "Error: %s\n", strerror(errno));
+        return;
+    }
+
+    len = sac->peek_stattr(sas, addr / TARGET_PAGE_SIZE, buflen, vals);
+    if (len < 0) {
+        monitor_printf(mon, "Error: %s", strerror(-len));
+        goto out;
+    }
+
+    monitor_printf(mon, "  CMMA attributes, "
+                   "pages %" PRIu64 "+%d (0x%" PRIx64 "):\n",
+                   addr / TARGET_PAGE_SIZE, len, addr & ~TARGET_PAGE_MASK);
+    for (cx = 0; cx < len; cx++) {
+        if (cx % 8 == 7) {
+            monitor_printf(mon, "%02x\n", vals[cx]);
+        } else {
+            monitor_printf(mon, "%02x", vals[cx]);
+        }
+    }
+    monitor_printf(mon, "\n");
+
+out:
+    g_free(vals);
+}
+
 /* Migration support: */
 
 static int cmma_load(QEMUFile *f, void *opaque, int version_id)

include/hw/s390x/storage-attributes.h

@@ -13,6 +13,7 @@
 #define S390_STORAGE_ATTRIBUTES_H
 
 #include <hw/qdev.h>
+#include "monitor/monitor.h"
 
 #define TYPE_S390_STATTRIB "s390-storage_attributes"
 #define TYPE_QEMU_S390_STATTRIB "s390-storage_attributes-qemu"
@@ -74,4 +75,7 @@ static inline Object *kvm_s390_stattrib_create(void)
 }
 #endif
 
+void hmp_info_cmma(Monitor *mon, const QDict *qdict);
+void hmp_migrationmode(Monitor *mon, const QDict *qdict);
+
 #endif /* S390_STORAGE_ATTRIBUTES_H */

monitor.c

@@ -81,6 +81,7 @@
 
 #if defined(TARGET_S390X)
 #include "hw/s390x/storage-keys.h"
+#include "hw/s390x/storage-attributes.h"
 #endif
 
 /*