[Qemu-devel] [PATCH 3/7] QemuState: Add additional states

[Luiz Capitulino <lcapitulino@redhat.com>]

Currently, only vm_start() and vm_stop() change the VM state. That's,
the state is only changed when starting or stopping the VM.

This commit adds the qemu_state_set() function, making it possible
to also do state transitions when qemu is stopped or running.

Additional states are also added and the current state is stored.
This is going to be used by the next commits.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
---
 cpus.c      |    1 +
 migration.c |    8 +++++++-
 sysemu.h    |   10 +++++++++-
 vl.c        |   20 ++++++++++++++++++++
 4 files changed, 37 insertions(+), 2 deletions(-)

diff --git a/cpus.c b/cpus.c
index ebbb8b9..48e6ca1 100644
--- a/cpus.c
+++ b/cpus.c
@@ -124,6 +124,7 @@ static void do_vm_stop(QemuState state)
         cpu_disable_ticks();
         vm_running = 0;
         pause_all_vcpus();
+        qemu_state_set(state);
         vm_state_notify(0, state);
         qemu_aio_flush();
         bdrv_flush_all();
diff --git a/migration.c b/migration.c
index 9724ce0..8aacf64 100644
--- a/migration.c
+++ b/migration.c
@@ -72,8 +72,11 @@ void process_incoming_migration(QEMUFile *f)
 
     incoming_expected = false;
 
-    if (autostart)
+    if (autostart) {
         vm_start();
+    } else {
+        qemu_state_set(QSTATE_PRELAUNCH);
+    }
 }
 
 int do_migrate(Monitor *mon, const QDict *qdict, QObject **ret_data)
@@ -394,6 +397,9 @@ void migrate_fd_put_ready(void *opaque)
             }
             state = MIG_STATE_ERROR;
         }
+        if (state == MIG_STATE_COMPLETED) {
+            qemu_state_set(QSTATE_POSTMIGRATE);
+        }
         s->state = state;
         notifier_list_notify(&migration_state_notifiers, NULL);
     }
diff --git a/sysemu.h b/sysemu.h
index 2c3ea3d..32c9abb 100644
--- a/sysemu.h
+++ b/sysemu.h
@@ -11,16 +11,22 @@
 /* vl.c */
 
 typedef enum {
+    QSTATE_NOSTATE,
     QSTATE_DEBUG,         /* qemu is running under gdb */
+    QSTATE_INMIGRATE,     /* paused waiting for an incoming migration */
     QSTATE_INTERROR,      /* paused due to an internal error */
     QSTATE_IOERROR,       /* paused due to an I/O error */
     QSTATE_PAUSED,        /* paused by the user (ie. the 'stop' command) */
+    QSTATE_POSTMIGRATE,   /* paused following a successful migration */
+    QSTATE_PRELAUNCH,     /* qemu was started with -S and haven't started */
     QSTATE_PREMIGRATE,    /* paused preparing to finish migrate */
     QSTATE_RESTVM,        /* paused restoring the VM state */
+    QSTATE_RESTVMFAILED,  /* paused due to a failed attempt to load state */
     QSTATE_RUNNING,       /* qemu is running */
     QSTATE_SAVEVM,        /* paused saving VM state */
     QSTATE_SHUTDOWN,      /* guest shut down and -no-shutdown is in use */
-    QSTATE_WATCHDOG       /* watchdog fired and qemu is configured to pause */
+    QSTATE_WATCHDOG,      /* watchdog fired and qemu is configured to pause */
+    QSTATE_MAX
 } QemuState;
 
 extern const char *bios_name;
@@ -31,6 +37,8 @@ extern uint8_t qemu_uuid[];
 int qemu_uuid_parse(const char *str, uint8_t *uuid);
 #define UUID_FMT "%02hhx%02hhx%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx-%02hhx%02hhx%02hhx%02hhx%02hhx%02hhx"
 
+QemuState qemu_state_get(void);
+void qemu_state_set(QemuState state);
 typedef struct vm_change_state_entry VMChangeStateEntry;
 typedef void VMChangeStateHandler(void *opaque, int running, QemuState state);
 
diff --git a/vl.c b/vl.c
index faa7c5f..2619c8e 100644
--- a/vl.c
+++ b/vl.c
@@ -320,6 +320,22 @@ static int default_driver_check(QemuOpts *opts, void *opaque)
 }
 
 /***********************************************************/
+/* QEMU state */
+
+static QemuState qemu_current_state = QSTATE_NOSTATE;
+
+QemuState qemu_state_get(void)
+{
+    return qemu_current_state;
+}
+
+void qemu_state_set(QemuState state)
+{
+    assert(state < QSTATE_MAX);
+    qemu_current_state = state;
+}
+
+/***********************************************************/
 /* real time host monotonic timer */
 
 /***********************************************************/
@@ -1158,6 +1174,7 @@ void vm_start(void)
     if (!vm_running) {
         cpu_enable_ticks();
         vm_running = 1;
+        qemu_state_set(QSTATE_RUNNING);
         vm_state_notify(1, QSTATE_RUNNING);
         resume_all_vcpus();
         monitor_protocol_event(QEVENT_RESUME, NULL);
@@ -3341,6 +3358,7 @@ int main(int argc, char **argv, char **envp)
     }
 
     if (incoming) {
+        qemu_state_set(QSTATE_INMIGRATE);
         int ret = qemu_start_incoming_migration(incoming);
         if (ret < 0) {
             fprintf(stderr, "Migration failed. Exit code %s(%d), exiting.\n",
@@ -3349,6 +3367,8 @@ int main(int argc, char **argv, char **envp)
         }
     } else if (autostart) {
         vm_start();
+    } else {
+        qemu_state_set(QSTATE_PRELAUNCH);
     }
 
     os_setup_post();
-- 
1.7.6.396.ge0613