Add a new mode argument to qemu_savevm_state() and qemu_loadvm_state() that
can customize the operation. Define the VMS_MIGRATE and VMS_SNAPSHOT modes
for the existing live migration and snapshot capabilities.
Provide a mode mask for vmstate handlers. A handler is only processed by
SAVEVM_FOREACH if its mask includes the savevm_state.mode. Unmodified
handler declarations have a zero mask field, which implicitly enables the
handler for all modes.
No functional change for the VMS_MIGRATE and VMS_SNAPSHOT modes.
Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
---
include/migration/register.h | 3 +++
include/migration/vmstate.h | 9 ++++++++
migration/migration.c | 4 ++--
migration/savevm.c | 51 +++++++++++++++++++++++++++++++++++---------
migration/savevm.h | 4 +++-
5 files changed, 58 insertions(+), 13 deletions(-)
diff --git a/include/migration/register.h b/include/migration/register.h
index c1dcff0..c030a10 100644
--- a/include/migration/register.h
+++ b/include/migration/register.h
@@ -17,6 +17,9 @@
#include "hw/vmstate-if.h"
typedef struct SaveVMHandlers {
+ /* Mask of VMStateMode's that should use this handler */
+ unsigned mode_mask;
+
/* This runs inside the iothread lock. */
SaveStateHandler *save_state;
diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h
index f68ed7d..fa575f9 100644
--- a/include/migration/vmstate.h
+++ b/include/migration/vmstate.h
@@ -158,6 +158,12 @@ typedef enum {
MIG_PRI_MAX,
} MigrationPriority;
+typedef enum {
+ VMS_MIGRATE = (1U << 1),
+ VMS_SNAPSHOT = (1U << 2),
+ VMS_MODE_ALL = ~0U
+} VMStateMode;
+
struct VMStateField {
const char *name;
const char *err_hint;
@@ -182,6 +188,7 @@ struct VMStateDescription {
int minimum_version_id;
int minimum_version_id_old;
MigrationPriority priority;
+ unsigned mode_mask;
LoadStateHandler *load_state_old;
int (*pre_load)(void *opaque);
int (*post_load)(void *opaque, int version_id);
@@ -1215,4 +1222,6 @@ void vmstate_register_ram_global(struct MemoryRegion
*memory);
bool vmstate_check_only_migratable(const VMStateDescription *vmsd);
+void savevm_set_mode(VMStateMode mode);
+
#endif
diff --git a/migration/migration.c b/migration/migration.c
index 2ed9923..e3d0899 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -465,7 +465,7 @@ static void process_incoming_migration_co(void *opaque)
postcopy_state_set(POSTCOPY_INCOMING_NONE);
migrate_set_state(&mis->state, MIGRATION_STATUS_NONE,
MIGRATION_STATUS_ACTIVE);
- ret = qemu_loadvm_state(mis->from_src_file);
+ ret = qemu_loadvm_state(mis->from_src_file, VMS_MIGRATE);
ps = postcopy_state_get();
trace_process_incoming_migration_co_end(ret, ps);
@@ -3414,7 +3414,7 @@ static void *migration_thread(void *opaque)
object_ref(OBJECT(s));
update_iteration_initial_status(s);
-
+ savevm_set_mode(VMS_MIGRATE);
qemu_savevm_state_header(s->to_dst_file);
/*
diff --git a/migration/savevm.c b/migration/savevm.c
index a07fcad..ce02b6b 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -256,6 +256,7 @@ typedef struct SaveState {
const char *name;
uint32_t target_page_bits;
uint32_t caps_count;
+ VMStateMode mode;
MigrationCapability *capabilities;
QemuUUID uuid;
} SaveState;
@@ -266,16 +267,15 @@ static SaveState savevm_state = {
.global_section_id = 0,
};
-/*
- * The FOREACH macros will filter handlers based on the current operation when
- * additional conditions are added in a subsequent patch.
- */
+/* The FOREACH macros filter handlers based on the current operation. */
#define SAVEVM_FOREACH(se, entry) \
QTAILQ_FOREACH(se, &savevm_state.handlers, entry) \
+ if (savevm_state.mode & mode_mask(se))
#define SAVEVM_FOREACH_SAFE(se, entry, new_se) \
QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se) \
+ if (savevm_state.mode & mode_mask(se))
/* The FORALL macros unconditionally loop over all handlers. */
@@ -285,6 +285,33 @@ static SaveState savevm_state = {
#define SAVEVM_FORALL_SAFE(se, entry, new_se) \
QTAILQ_FOREACH_SAFE(se, &savevm_state.handlers, entry, new_se)
+/*
+ * Set the current mode to be used for filtering savevm handlers in
+ * SAVEVM_FOREACH.
+ */
+void savevm_set_mode(VMStateMode mode)
+{
+ savevm_state.mode = mode;
+}
+
+/*
+ * A savevm handler is selected in SAVEVM_FOREACH if its mask overlaps the
+ * current mode. The mask is defined by either the new vmsd interface or the
+ * legacy ops interface. If the mask is zero, it implicily includes all modes.
+ */
+static inline unsigned mode_mask(SaveStateEntry *se)
+{
+ const VMStateDescription *vmsd = se->vmsd;
+ unsigned mask = 0;
+
+ if (vmsd) {
+ mask = vmsd->mode_mask;
+ } else if (se->ops) {
+ mask = se->ops->mode_mask;
+ }
+ return mask ? mask : VMS_MODE_ALL;
+}
+
static bool should_validate_capability(int capability)
{
assert(capability >= 0 && capability < MIGRATION_CAPABILITY__MAX);
@@ -1527,12 +1554,14 @@ void qemu_savevm_state_cleanup(void)
}
}
-static int qemu_savevm_state(QEMUFile *f, Error **errp)
+static int qemu_savevm_state(QEMUFile *f, VMStateMode mode, Error **errp)
{
int ret;
MigrationState *ms = migrate_get_current();
MigrationStatus status;
+ savevm_set_mode(mode);
+
if (migration_is_running(ms->state)) {
error_setg(errp, QERR_MIGRATION_ACTIVE);
return -EINVAL;
@@ -2557,13 +2586,14 @@ out:
return ret;
}
-int qemu_loadvm_state(QEMUFile *f)
+int qemu_loadvm_state(QEMUFile *f, VMStateMode mode)
{
MigrationIncomingState *mis = migration_incoming_get_current();
Error *local_err = NULL;
int ret;
- if (qemu_savevm_state_blocked(&local_err)) {
+ if ((mode & (VMS_SNAPSHOT | VMS_MIGRATE)) &&
+ qemu_savevm_state_blocked(&local_err)) {
error_report_err(local_err);
return -EINVAL;
}
@@ -2736,7 +2766,7 @@ int save_snapshot(const char *name, Error **errp)
error_setg(errp, "Could not open VM state file");
goto the_end;
}
- ret = qemu_savevm_state(f, errp);
+ ret = qemu_savevm_state(f, VMS_SNAPSHOT, errp);
vm_state_size = qemu_ftell(f);
ret2 = qemu_fclose(f);
if (ret < 0) {
@@ -2785,6 +2815,7 @@ void qmp_xen_save_devices_state(const char *filename,
bool has_live, bool live,
int saved_vm_running;
int ret;
+ savevm_set_mode(VMS_MIGRATE);
if (!has_live) {
/* live default to true so old version of Xen tool stack can have a
* successfull live migration */
@@ -2850,7 +2881,7 @@ void qmp_xen_load_devices_state(const char *filename,
Error **errp)
f = qemu_fopen_channel_input(QIO_CHANNEL(ioc));
object_unref(OBJECT(ioc));
- ret = qemu_loadvm_state(f);
+ ret = qemu_loadvm_state(f, VMS_MIGRATE);
qemu_fclose(f);
if (ret < 0) {
error_setg(errp, QERR_IO_ERROR);
@@ -2928,7 +2959,7 @@ int load_snapshot(const char *name, Error **errp)
mis->from_src_file = f;
aio_context_acquire(aio_context);
- ret = qemu_loadvm_state(f);
+ ret = qemu_loadvm_state(f, VMS_SNAPSHOT);
migration_incoming_state_destroy();
aio_context_release(aio_context);
diff --git a/migration/savevm.h b/migration/savevm.h
index ba64a7e..4b7ce91 100644
--- a/migration/savevm.h
+++ b/migration/savevm.h
@@ -14,6 +14,8 @@
#ifndef MIGRATION_SAVEVM_H
#define MIGRATION_SAVEVM_H
+#include "migration/vmstate.h"
+
#define QEMU_VM_FILE_MAGIC 0x5145564d
#define QEMU_VM_FILE_VERSION_COMPAT 0x00000002
#define QEMU_VM_FILE_VERSION 0x00000003
@@ -60,7 +62,7 @@ void qemu_savevm_send_colo_enable(QEMUFile *f);
void qemu_savevm_live_state(QEMUFile *f);
int qemu_save_device_state(QEMUFile *f);
-int qemu_loadvm_state(QEMUFile *f);
+int qemu_loadvm_state(QEMUFile *f, VMStateMode mode);
void qemu_loadvm_state_cleanup(void);
int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis);
int qemu_load_device_state(QEMUFile *f);
--
1.8.3.1
