[RFC v4 PATCH 46/49] multi-process/mig: Restore the VMSD in remote process

[Jagannathan Raman <jag.raman@oracle.com>]

From: Elena Ufimtseva <elena.ufimtseva@oracle.com>

The remote process accepts the VMSD from Proxy object and
restores it

Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
---
 New patch in v4

 migration/savevm.c   | 36 ++++++++++++++++++++++++++++++++++++
 migration/savevm.h   |  1 +
 remote/remote-main.c | 34 ++++++++++++++++++++++++++++++++++
 3 files changed, 71 insertions(+)

diff --git a/migration/savevm.c b/migration/savevm.c
index 0c84142..d730cd1 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -2930,3 +2930,39 @@ int qemu_remote_savevm(QEMUFile *f)
 
     return 0;
 }
+
+int qemu_remote_loadvm(QEMUFile *f)
+{
+    uint8_t section_type;
+    int ret = 0;
+
+    qemu_mutex_lock_iothread();
+
+    while (true) {
+        section_type = qemu_get_byte(f);
+
+        if (qemu_file_get_error(f)) {
+            ret = qemu_file_get_error(f);
+            break;
+        }
+
+        switch (section_type) {
+        case QEMU_VM_SECTION_FULL:
+            ret = qemu_loadvm_section_start_full(f, NULL);
+            if (ret < 0) {
+                break;
+            }
+            break;
+        case QEMU_VM_EOF:
+            goto out;
+        default:
+            ret = -EINVAL;
+            goto out;
+        }
+    }
+
+out:
+    qemu_mutex_unlock_iothread();
+
+    return ret;
+}
diff --git a/migration/savevm.h b/migration/savevm.h
index a6582ac..415b72c 100644
--- a/migration/savevm.h
+++ b/migration/savevm.h
@@ -65,5 +65,6 @@ int qemu_loadvm_state_main(QEMUFile *f, MigrationIncomingState *mis);
 int qemu_load_device_state(QEMUFile *f);
 
 int qemu_remote_savevm(QEMUFile *f);
+int qemu_remote_loadvm(QEMUFile *f);
 
 #endif
diff --git a/remote/remote-main.c b/remote/remote-main.c
index 2de5ddf..600c894 100644
--- a/remote/remote-main.c
+++ b/remote/remote-main.c
@@ -81,6 +81,7 @@
 #include "chardev/char.h"
 #include "sysemu/reset.h"
 #include "vl.h"
+#include "migration/misc.h"
 
 static MPQemuLinkState *mpqemu_link;
 
@@ -403,6 +404,30 @@ static void process_start_mig_out(MPQemuMsg *msg)
     qemu_fclose(f);
 }
 
+static int process_start_mig_in(MPQemuMsg *msg)
+{
+    Error *err = NULL;
+    QIOChannel *ioc;
+    QEMUFile *f;
+    int rc = -EINVAL;
+
+    ioc = qio_channel_new_fd(msg->fds[0], &err);
+    if (err) {
+        error_report_err(err);
+        return rc;
+    }
+
+    qio_channel_set_name(QIO_CHANNEL(ioc), "remote-migration-channel");
+
+    f = qemu_fopen_channel_input(ioc);
+
+    rc = qemu_remote_loadvm(f);
+
+    qemu_fclose(f);
+
+    return rc;
+}
+
 static void process_msg(GIOCondition cond, MPQemuChannel *chan)
 {
     MPQemuMsg *msg = NULL;
@@ -498,6 +523,13 @@ static void process_msg(GIOCondition cond, MPQemuChannel *chan)
     case START_MIG_OUT:
         process_start_mig_out(msg);
         break;
+    case START_MIG_IN:
+        if (process_start_mig_in(msg))
+        {
+            error_setg(&err, "Incoming migration failed.");
+            goto finalize_loop;
+        }
+        break;
     case RUNSTATE_SET:
         remote_runstate_set(msg->data1.runstate.state);
         break;
@@ -569,6 +601,8 @@ int main(int argc, char *argv[])
     }
     mpqemu_init_channel(mpqemu_link, &mpqemu_link->mmio, fd);
 
+    migration_object_init();
+
     parse_cmdline(argc - 3, argv + 3, NULL);
 
     mpqemu_link_set_callback(mpqemu_link, process_msg);
-- 
1.8.3.1