From b5a3f9ac5db568ddfb572d11fb4d6a659c0f5bfa Mon Sep 17 00:00:00 2001
From: Dr. David Alan Gilbert (git) <dgilbert@redhat.com>
Date: Wed, 15 Jan 2014 19:42:28 +0100
Subject: [PATCH 02/34] introduce MIG_STATE_CANCELLING state

RH-Author: Dr. David Alan Gilbert (git) <dgilbert@redhat.com>
Message-id: <1389814948-3983-3-git-send-email-dgilbert@redhat.com>
Patchwork-id: 56731
O-Subject: [RHEL-7.0 qemu-kvm PATCH 2/2] introduce MIG_STATE_CANCELLING state
Bugzilla: 1053699
RH-Acked-by: Orit Wasserman <owasserm@redhat.com>
RH-Acked-by: Juan Quintela <quintela@redhat.com>
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>

From: "Zhanghaoyu (A)" <haoyu.zhang@huawei.com>

Introduce MIG_STATE_CANCELLING state to avoid starting a new migration task while the previous one still exist.

Signed-off-by: Zeng Junliang <zengjunliang@huawei.com>
Signed-off-by: Zhang Haoyu <haoyu.zhang@huawei.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
(cherry picked from commit 51cf4c1a99a172679c2949a2d58a2a4ee307b557)

Conflicts:
	migration.c
---
 migration.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 migration.c |   26 ++++++++++++++++----------
 1 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/migration.c b/migration.c
index 735f7ca..21f7247 100644
--- a/migration.c
+++ b/migration.c
@@ -39,6 +39,7 @@ enum {
     MIG_STATE_ERROR = -1,
     MIG_STATE_NONE,
     MIG_STATE_SETUP,
+    MIG_STATE_CANCELLING,
     MIG_STATE_CANCELLED,
     MIG_STATE_ACTIVE,
     MIG_STATE_COMPLETED,
@@ -194,6 +195,7 @@ MigrationInfo *qmp_query_migrate(Error **errp)
         info->has_total_time = false;
         break;
     case MIG_STATE_ACTIVE:
+    case MIG_STATE_CANCELLING:
         info->has_status = true;
         info->status = g_strdup("active");
         info->has_total_time = true;
@@ -280,6 +282,13 @@ void qmp_migrate_set_capabilities(MigrationCapabilityStatusList *params,
 
 /* shared migration helpers */
 
+static void migrate_set_state(MigrationState *s, int old_state, int new_state)
+{
+    if (atomic_cmpxchg(&s->state, old_state, new_state) == new_state) {
+        trace_migrate_set_state(new_state);
+    }
+}
+
 static void migrate_fd_cleanup(void *opaque)
 {
     MigrationState *s = opaque;
@@ -301,18 +310,14 @@ static void migrate_fd_cleanup(void *opaque)
 
     if (s->state != MIG_STATE_COMPLETED) {
         qemu_savevm_state_cancel();
+        if (s->state == MIG_STATE_CANCELLING) {
+            migrate_set_state(s, MIG_STATE_CANCELLING, MIG_STATE_CANCELLED);
+        }
     }
 
     notifier_list_notify(&migration_state_notifiers, s);
 }
 
-static void migrate_set_state(MigrationState *s, int old_state, int new_state)
-{
-    if (atomic_cmpxchg(&s->state, old_state, new_state) == new_state) {
-        trace_migrate_set_state(new_state);
-    }
-}
-
 void migrate_fd_error(MigrationState *s)
 {
     DPRINTF("setting error state\n");
@@ -332,8 +337,8 @@ static void migrate_fd_cancel(MigrationState *s)
         if (old_state != MIG_STATE_SETUP && old_state != MIG_STATE_ACTIVE) {
             break;
         }
-        migrate_set_state(s, old_state, MIG_STATE_CANCELLED);
-    } while (s->state != MIG_STATE_CANCELLED);
+        migrate_set_state(s, old_state, MIG_STATE_CANCELLING);
+    } while (s->state != MIG_STATE_CANCELLING);
 }
 
 void add_migration_state_change_notifier(Notifier *notify)
@@ -418,7 +423,8 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
     }
 #endif
 
-    if (s->state == MIG_STATE_ACTIVE || s->state == MIG_STATE_SETUP) {
+    if (s->state == MIG_STATE_ACTIVE || s->state == MIG_STATE_SETUP ||
+        s->state == MIG_STATE_CANCELLING) {
         error_set(errp, QERR_MIGRATION_ACTIVE);
         return;
     }
-- 
1.7.1