block: add 'node-name' field to BLOCK_IMAGE_CORRUPTED

Since this event can occur in nodes that cannot have a device name
associated, include also a field with the node name.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 147cec5b3594f4bec0cb41c98afe5fcbfb67567c.1428485266.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/qcow2.c

@@ -2824,6 +2824,7 @@ void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
                              int64_t size, const char *message_format, ...)
 {
     BDRVQcowState *s = bs->opaque;
+    const char *node_name;
     char *message;
     va_list ap;
 
@@ -2847,8 +2848,11 @@ void qcow2_signal_corruption(BlockDriverState *bs, bool fatal, int64_t offset,
                 "corruption events will be suppressed\n", message);
     }
 
-    qapi_event_send_block_image_corrupted(bdrv_get_device_name(bs), message,
+    node_name = bdrv_get_node_name(bs);
-                                          offset >= 0, offset, size >= 0, size,
+    qapi_event_send_block_image_corrupted(bdrv_get_device_name(bs),
+                                          *node_name != '\0', node_name,
+                                          message, offset >= 0, offset,
+                                          size >= 0, size,
                                           fatal, &error_abort);
     g_free(message);
 

docs/qmp/qmp-events.txt

@@ -31,21 +31,26 @@ Example:
 BLOCK_IMAGE_CORRUPTED
 ---------------------
 
-Emitted when a disk image is being marked corrupt.
+Emitted when a disk image is being marked corrupt. The image can be
+identified by its device or node name. The 'device' field is always
+present for compatibility reasons, but it can be empty ("") if the
+image does not have a device name associated.
 
 Data:
 
-- "device": Device name (json-string)
+- "device":    Device name (json-string)
-- "msg":    Informative message (e.g., reason for the corruption) (json-string)
+- "node-name": Node name (json-string, optional)
-- "offset": If the corruption resulted from an image access, this is the access
+- "msg":       Informative message (e.g., reason for the corruption)
-            offset into the image (json-int)
+               (json-string)
-- "size":   If the corruption resulted from an image access, this is the access
+- "offset":    If the corruption resulted from an image access, this
-            size (json-int)
+               is the access offset into the image (json-int)
+- "size":      If the corruption resulted from an image access, this
+               is the access size (json-int)
 
 Example:
 
 { "event": "BLOCK_IMAGE_CORRUPTED",
-    "data": { "device": "ide0-hd0",
+    "data": { "device": "ide0-hd0", "node-name": "node0",
         "msg": "Prevented active L1 table overwrite", "offset": 196608,
         "size": 65536 },
     "timestamp": { "seconds": 1378126126, "microseconds": 966463 } }

qapi/block-core.json

@@ -1757,7 +1757,11 @@
 #
 # Emitted when a corruption has been detected in a disk image
 #
-# @device: device name
+# @device: device name. This is always present for compatibility
+#          reasons, but it can be empty ("") if the image does not
+#          have a device name associated.
+#
+# @node-name: #optional node name (Since: 2.4)
 #
 # @msg: informative message for human consumption, such as the kind of
 #       corruption being detected. It should not be parsed by machine as it is
@@ -1776,11 +1780,12 @@
 # Since: 1.7
 ##
 { 'event': 'BLOCK_IMAGE_CORRUPTED',
-  'data': { 'device' : 'str',
+  'data': { 'device'     : 'str',
-            'msg'    : 'str',
+            '*node-name' : 'str',
-            '*offset': 'int',
+            'msg'        : 'str',
-            '*size'  : 'int',
+            '*offset'    : 'int',
-            'fatal'  : 'bool' } }
+            '*size'      : 'int',
+            'fatal'      : 'bool' } }
 
 ##
 # @BLOCK_IO_ERROR