[Qemu-devel] [PATCH RFC v2 7/8] migration: add dirty parameter

[Vladimir Sementsov-Ogievskiy <vsementsov@parallels.com>]

Add dirty parameter to qmp-migrate command. If this parameter is true,
migration/block.c will migrate dirty bitmaps. This parameter can be used
without "blk" parameter to migrate only dirty bitmaps, skipping block
migration.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@parallels.com>
---
 hmp-commands.hx               | 12 +++++++-----
 hmp.c                         |  4 +++-
 include/migration/migration.h |  1 +
 migration/migration.c         |  4 +++-
 qapi-schema.json              |  7 ++++++-
 qmp-commands.hx               |  5 ++++-
 savevm.c                      |  3 ++-
 7 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/hmp-commands.hx b/hmp-commands.hx
index a9be506..c16f93c 100644
--- a/hmp-commands.hx
+++ b/hmp-commands.hx
@@ -902,23 +902,25 @@ ETEXI
 
     {
         .name       = "migrate",
-        .args_type  = "detach:-d,blk:-b,inc:-i,uri:s",
-        .params     = "[-d] [-b] [-i] uri",
+        .args_type  = "detach:-d,blk:-b,inc:-i,dirty:-D,uri:s",
+        .params     = "[-d] [-b] [-i] [-D] uri",
         .help       = "migrate to URI (using -d to not wait for completion)"
 		      "\n\t\t\t -b for migration without shared storage with"
 		      " full copy of disk\n\t\t\t -i for migration without "
-		      "shared storage with incremental copy of disk "
-		      "(base image shared between src and destination)",
+		      "shared storage with incremental copy of disk\n\t\t\t"
+		      " -D for migration of named dirty bitmaps as well\n\t\t\t"
+		      " (base image shared between src and destination)",
         .mhandler.cmd = hmp_migrate,
     },
 
 
 STEXI
-@item migrate [-d] [-b] [-i] @var{uri}
+@item migrate [-d] [-b] [-i] [-D] @var{uri}
 @findex migrate
 Migrate to @var{uri} (using -d to not wait for completion).
 	-b for migration with full copy of disk
 	-i for migration with incremental copy of disk (base image is shared)
+	-D for migration of named dirty bitmaps
 ETEXI
 
     {
diff --git a/hmp.c b/hmp.c
index a269145..0b89ee8 100644
--- a/hmp.c
+++ b/hmp.c
@@ -1347,10 +1347,12 @@ void hmp_migrate(Monitor *mon, const QDict *qdict)
     int detach = qdict_get_try_bool(qdict, "detach", 0);
     int blk = qdict_get_try_bool(qdict, "blk", 0);
     int inc = qdict_get_try_bool(qdict, "inc", 0);
+    int dirty = qdict_get_try_bool(qdict, "dirty", 0);
     const char *uri = qdict_get_str(qdict, "uri");
     Error *err = NULL;
 
-    qmp_migrate(uri, !!blk, blk, !!inc, inc, false, false, &err);
+    qmp_migrate(uri, !!blk, blk, !!inc, inc, !!dirty, dirty,
+                false, false, &err);
     if (err) {
         monitor_printf(mon, "migrate: %s\n", error_get_pretty(err));
         error_free(err);
diff --git a/include/migration/migration.h b/include/migration/migration.h
index 3cb5ba8..48d71d3 100644
--- a/include/migration/migration.h
+++ b/include/migration/migration.h
@@ -37,6 +37,7 @@
 struct MigrationParams {
     bool blk;
     bool shared;
+    bool dirty;
 };
 
 typedef struct MigrationState MigrationState;
diff --git a/migration/migration.c b/migration/migration.c
index c49a05a..e7bb7f3 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -404,7 +404,8 @@ void migrate_del_blocker(Error *reason)
 }
 
 void qmp_migrate(const char *uri, bool has_blk, bool blk,
-                 bool has_inc, bool inc, bool has_detach, bool detach,
+                 bool has_inc, bool inc, bool has_dirty, bool dirty,
+                 bool has_detach, bool detach,
                  Error **errp)
 {
     Error *local_err = NULL;
@@ -414,6 +415,7 @@ void qmp_migrate(const char *uri, bool has_blk, bool blk,
 
     params.blk = has_blk && blk;
     params.shared = has_inc && inc;
+    params.dirty = has_dirty && dirty;
 
     if (s->state == MIG_STATE_ACTIVE || s->state == MIG_STATE_SETUP ||
         s->state == MIG_STATE_CANCELLING) {
diff --git a/qapi-schema.json b/qapi-schema.json
index 1475f69..1d10d6b 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -1656,12 +1656,17 @@
 # @detach: this argument exists only for compatibility reasons and
 #          is ignored by QEMU
 #
+# @dirty: #optional do dirty-bitmaps migration (can be used with or without
+#         @blk parameter)
+#         (since 2.3)
+#
 # Returns: nothing on success
 #
 # Since: 0.14.0
 ##
 { 'command': 'migrate',
-  'data': {'uri': 'str', '*blk': 'bool', '*inc': 'bool', '*detach': 'bool' } }
+  'data': { 'uri': 'str', '*blk': 'bool', '*inc': 'bool', '*dirty': 'bool',
+            '*detach': 'bool' } }
 
 # @xen-save-devices-state:
 #
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 8065715..f8e50ac 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -610,7 +610,7 @@ EQMP
 
     {
         .name       = "migrate",
-        .args_type  = "detach:-d,blk:-b,inc:-i,uri:s",
+        .args_type  = "detach:-d,blk:-b,inc:-i,dirty:-D,uri:s",
         .mhandler.cmd_new = qmp_marshal_input_migrate,
     },
 
@@ -624,6 +624,7 @@ Arguments:
 
 - "blk": block migration, full disk copy (json-bool, optional)
 - "inc": incremental disk copy (json-bool, optional)
+- "dirty": migrate named dirty bitmaps (json-bool, optional)
 - "uri": Destination URI (json-string)
 
 Example:
@@ -638,6 +639,8 @@ Notes:
 (2) All boolean arguments default to false
 (3) The user Monitor's "detach" argument is invalid in QMP and should not
     be used
+(4) The "dirty" argument may be used without "blk", to migrate only dirty
+    bitmaps
 
 EQMP
 
diff --git a/savevm.c b/savevm.c
index 08ec678..a598d1d 100644
--- a/savevm.c
+++ b/savevm.c
@@ -784,7 +784,8 @@ static int qemu_savevm_state(QEMUFile *f)
     int ret;
     MigrationParams params = {
         .blk = 0,
-        .shared = 0
+        .shared = 0,
+        .dirty = 0
     };
 
     if (qemu_savevm_state_blocked(NULL)) {
-- 
1.9.1