[Qemu-devel] [PATCH 7/9] global_state: Make section optional

[Juan Quintela]

This section would be sent:

a- for all new machine types
b- for old achine types if section state is different form {running,paused}
   that were the only giving us troubles.

So, in new qemus: it is alwasy there.  In old qemus: they are only
there if it an error has happened, basically stoping on target.

Signed-off-by: Juan Quintela <address@hidden>
---
 hw/i386/pc_piix.c             |  2 ++
 hw/i386/pc_q35.c              |  2 ++
 include/migration/migration.h |  2 +-
 migration/migration.c         | 29 +++++++++++++++++++++++++++++
 4 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index 212e263..5c04784 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -52,6 +52,7 @@
 #ifdef CONFIG_XEN
 #  include <xen/hvm/hvm_info_table.h>
 #endif
+#include "migration/migration.h"

 #define MAX_IDE_BUS 2

@@ -312,6 +313,7 @@ static void pc_init_pci(MachineState *machine)

 static void pc_compat_2_3(MachineState *machine)
 {
+    global_state_set_optional();
 }

 static void pc_compat_2_2(MachineState *machine)
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index e67f2de..cc5827a 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -45,6 +45,7 @@
 #include "hw/usb.h"
 #include "hw/cpu/icc_bus.h"
 #include "qemu/error-report.h"
+#include "migration/migration.h"

 /* ICH9 AHCI has 6 ports */
 #define MAX_SATA_PORTS     6
@@ -291,6 +292,7 @@ static void pc_q35_init(MachineState *machine)

 static void pc_compat_2_3(MachineState *machine)
 {
+    global_state_set_optional();
 }

 static void pc_compat_2_2(MachineState *machine)
diff --git a/include/migration/migration.h b/include/migration/migration.h
index 785c2dc..f939d88 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -183,5 +183,5 @@ size_t ram_control_save_page(QEMUFile *f, ram_addr_t 
block_offset,
 void register_global_state(void);
 void global_state_store(void);
 char *global_state_get_runstate(void);
-
+void global_state_set_optional(void);
 #endif
diff --git a/migration/migration.c b/migration/migration.c
index ab69f81..1035689 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -868,6 +868,7 @@ void migrate_fd_connect(MigrationState *s)
 }

 typedef struct {
+    bool optional;
     int32_t size;
     uint8_t runstate[100];
 } GlobalState;
@@ -888,6 +889,33 @@ char *global_state_get_runstate(void)
     return (char *)global_state.runstate;
 }

+void global_state_set_optional(void)
+{
+    global_state.optional = true;
+}
+
+static bool global_state_needed(void *opaque)
+{
+    GlobalState *s = opaque;
+    char *runstate = (char *)s->runstate;
+
+    /* If it is not optional, it is mandatory */
+
+    if (s->optional == false) {
+        return true;
+    }
+
+    /* If state is running or paused, it is not needed */
+
+    if (strcmp(runstate, "running") == 0 ||
+        strcmp(runstate, "paused") == 0) {
+        return false;
+    }
+
+    /* for any other state it is needed */
+    return true;
+}
+
 static int global_state_post_load(void *opaque, int version_id)
 {
     GlobalState *s = opaque;
@@ -921,6 +949,7 @@ static const VMStateDescription vmstate_globalstate = {
     .minimum_version_id = 1,
     .post_load = global_state_post_load,
     .pre_save = global_state_pre_save,
+    .needed = global_state_needed,
     .fields = (VMStateField[]) {
         VMSTATE_INT32(size, GlobalState),
         VMSTATE_BUFFER(runstate, GlobalState),
-- 
2.4.0