[Qemu-devel] [RFC V3 2/7] block: Allow the user to define "node-name" option.

[Benoît Canet]

Signed-off-by: Benoit Canet <ben...@irqsave.net>
---
 block.c | 42 +++++++++++++++++++++++++++++++++++++-----
 1 file changed, 37 insertions(+), 5 deletions(-)

diff --git a/block.c b/block.c
index 4f6b36a..3a0cb30 100644
--- a/block.c
+++ b/block.c
@@ -873,6 +873,7 @@ int bdrv_file_open(BlockDriverState **pbs, const char 
*filename,
     const char *drvname;
     bool allow_protocol_prefix = false;
     Error *local_err = NULL;
+    const char *node_name = NULL;
     int ret;
 
     /* NULL means an empty set of options */
@@ -880,7 +881,14 @@ int bdrv_file_open(BlockDriverState **pbs, const char 
*filename,
         options = qdict_new();
     }
 
-    bs = bdrv_new("", "");
+    node_name = qdict_get_try_str(options, "node-name");
+    if (node_name && bdrv_find_node(node_name)) {
+        error_setg(errp, "Duplicate node name");
+        return -EINVAL;
+    }
+    bs = bdrv_new("", node_name ? node_name : "");
+    qdict_del(options, "node-name");
+
     bs->options = options;
     options = qdict_clone_shallow(options);
 
@@ -980,6 +988,7 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict 
*options, Error **errp)
     int back_flags, ret;
     BlockDriver *back_drv = NULL;
     Error *local_err = NULL;
+    const char *node_name = NULL;
 
     if (bs->backing_hd != NULL) {
         QDECREF(options);
@@ -1002,7 +1011,14 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict 
*options, Error **errp)
                                        sizeof(backing_filename));
     }
 
-    bs->backing_hd = bdrv_new("", "");
+    node_name = qdict_get_try_str(options, "node-name");
+    if (node_name && bdrv_find_node(node_name)) {
+        error_setg(errp, "Duplicate node name");
+        QDECREF(options);
+        return -EINVAL;
+    }
+    bs->backing_hd = bdrv_new("", node_name ? node_name : "");
+    qdict_del(options, "node-name");
 
     if (bs->backing_format[0] != '\0') {
         back_drv = bdrv_find_format(bs->backing_format);
@@ -1046,6 +1062,7 @@ int bdrv_open(BlockDriverState *bs, const char *filename, 
QDict *options,
     BlockDriverState *file = NULL;
     QDict *file_options = NULL;
     const char *drvname;
+    const char *node_name = NULL;
     Error *local_err = NULL;
 
     /* NULL means an empty set of options */
@@ -1053,6 +1070,21 @@ int bdrv_open(BlockDriverState *bs, const char 
*filename, QDict *options,
         options = qdict_new();
     }
 
+    node_name = qdict_get_try_str(options, "node-name");
+    if (node_name && bdrv_find_node(node_name)) {
+        error_setg(errp, "Duplicate node name");
+        return -EINVAL;
+    }
+
+    if (node_name) {
+        pstrcpy(bs->node_name, sizeof(bs->node_name), node_name);
+        if (node_name[0] != '\0') {
+            QTAILQ_INSERT_TAIL(&graph_bdrv_states, bs, node_list);
+        }
+    }
+
+    qdict_del(options, "node-name");
+
     bs->options = options;
     options = qdict_clone_shallow(options);
 
@@ -1646,9 +1678,9 @@ static void bdrv_move_feature_fields(BlockDriverState 
*bs_dest,
             bs_src->device_name);
     bs_dest->device_list = bs_src->device_list;
 
-    /* keep the same entry in graph_bdrv_states */
-    pstrcpy(bs_dest->node_name, sizeof(bs_dest->node_name),
-            bs_src->node_name);
+    /* keep the same entry in graph_bdrv_states
+     * We do want to swap name but don't want to swap linked list entries
+     */
     bs_dest->node_list   = bs_src->node_list;
 }
 
-- 
1.8.3.2