[Qemu-devel] [PATCH V8 10/20] qmp: add interface query-snapshots

[Wenchao Xia <xiawenc@linux.vnet.ibm.com>]

  This interface now return valid internal snapshots for whole vm.

Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
---
 block/qapi.c     |   22 +++++++++++++++++++++
 qapi-schema.json |   14 +++++++++++++
 qmp-commands.hx  |   55 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 91 insertions(+), 0 deletions(-)

diff --git a/block/qapi.c b/block/qapi.c
index 0c3055f..b903dd8 100644
--- a/block/qapi.c
+++ b/block/qapi.c
@@ -14,6 +14,7 @@
 #include "block/qapi.h"
 #include "block/snapshot.h"
 #include "block/block_int.h"
+#include "qmp-commands.h"
 
 /*
  * check whether the snapshot is valid for whole vm.
@@ -180,3 +181,24 @@ int bdrv_query_image_info(BlockDriverState *bs,
     *p_info = info;
     return 0;
 }
+
+SnapshotInfoList *qmp_query_snapshots(Error **errp)
+{
+    BlockDriverState *bs;
+    SnapshotInfoList *list = NULL;
+    int ret;
+
+    /* internal snapshot for whole vm */
+    bs = bdrv_snapshots();
+    if (!bs) {
+        error_setg(errp, "No available block device supports snapshots\n");
+        return NULL;
+    }
+
+    ret = bdrv_query_snapshot_info_list(bs, &list, true, errp);
+    if (ret < 0) {
+        qapi_free_SnapshotInfoList(list);
+        list = NULL;
+    }
+    return list;
+}
diff --git a/qapi-schema.json b/qapi-schema.json
index 28b070f..3710495 100644
--- a/qapi-schema.json
+++ b/qapi-schema.json
@@ -839,6 +839,20 @@
 { 'command': 'query-block', 'returns': ['BlockInfo'] }
 
 ##
+# @query-snapshots:
+#
+# Get a list of internal snapshots for whole virtual machine, only valid
+# internal snapshot will be returned, inconsistent ones will be ignored
+#
+# Returns: a list of @SnapshotInfo describing all consistent virtual machine
+#          snapshots
+#
+# Since: 1.5
+##
+{ 'command': 'query-snapshots',
+  'returns': ['SnapshotInfo'] }
+
+##
 # @BlockDeviceStats:
 #
 # Statistics of a virtual block device or a block backing device.
diff --git a/qmp-commands.hx b/qmp-commands.hx
index 95022e2..d505209 100644
--- a/qmp-commands.hx
+++ b/qmp-commands.hx
@@ -1743,6 +1743,61 @@ EQMP
     },
 
 SQMP
+query-snapshots
+-----------
+
+Show the internal consistent snapshot information
+
+Each snapshot is represented by a json-object. The returned value
+is a json-array of all snapshots
+
+Each json-object contain the following:
+
+- "id": unique snapshot id (json-string)
+- "name": internal snapshot name (json-string)
+- "vm-state-size": size of the VM state in bytes (json-int)
+- "date-sec": UTC date of the snapshot in seconds (json-int)
+- "date-nsec": fractional part in nano seconds to be used with
+               date-sec(json-int)
+- "vm-clock-sec": VM clock relative to boot in seconds (json-int)
+- "vm-clock-nsec": fractional part in nano seconds to be used with
+                   vm-clock-sec (json-int)
+
+Example:
+
+-> { "execute": "query-snapshots" }
+<- {
+      "return":[
+         {
+            "id": "1",
+            "name": "snapshot1",
+            "vm-state-size": 0,
+            "date-sec": 10000200,
+            "date-nsec": 12,
+            "vm-clock-sec": 206,
+            "vm-clock-nsec": 30
+         },
+         {
+            "id": "2",
+            "name": "snapshot2",
+            "vm-state-size": 34000000,
+            "date-sec": 13000200,
+            "date-nsec": 32,
+            "vm-clock-sec": 406,
+            "vm-clock-nsec": 31
+         }
+      ]
+   }
+
+EQMP
+
+    {
+        .name       = "query-snapshots",
+        .args_type  = "",
+        .mhandler.cmd_new = qmp_marshal_input_query_snapshots,
+    },
+
+SQMP
 query-blockstats
 ----------------
 
-- 
1.7.1