block: use bdrv_get_device_or_node_name() in error messages

There are several error messages that identify a BlockDriverState by
its device name. However those errors can be produced in nodes that
don't have a device name associated.

In those cases we should use bdrv_get_device_or_node_name() to fall
back to the node name and produce a more meaningful message. The
messages are also updated to use the more generic term 'node' instead
of 'device'.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 9823a1f0514fdb0692e92868661c38a9e00a12d6.1428485266.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/block.c b/block.c
index cc8010e..002972a 100644
--- a/block.c
+++ b/block.c
@@ -1231,8 +1231,8 @@
         bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
     } else if (backing_hd) {
         error_setg(&bs->backing_blocker,
-                   "device is used as backing hd of '%s'",
-                   bdrv_get_device_name(bs));
+                   "node is used as backing hd of '%s'",
+                   bdrv_get_device_or_node_name(bs));
     }
 
     bs->backing_hd = backing_hd;
@@ -1819,8 +1819,8 @@
      * to r/w */
     if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) &&
         reopen_state->flags & BDRV_O_RDWR) {
-        error_set(errp, QERR_DEVICE_IS_READ_ONLY,
-                  bdrv_get_device_name(reopen_state->bs));
+        error_setg(errp, "Node '%s' is read only",
+                   bdrv_get_device_or_node_name(reopen_state->bs));
         goto error;
     }
 
@@ -1846,9 +1846,9 @@
     } else {
         /* It is currently mandatory to have a bdrv_reopen_prepare()
          * handler for each supported drv. */
-        error_set(errp, QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
-                  drv->format_name, bdrv_get_device_name(reopen_state->bs),
-                 "reopening of file");
+        error_setg(errp, "Block format '%s' used by node '%s' "
+                   "does not support reopening files", drv->format_name,
+                   bdrv_get_device_or_node_name(reopen_state->bs));
         ret = -1;
         goto error;
     }
@@ -3824,8 +3824,8 @@
 {
     if (key) {
         if (!bdrv_is_encrypted(bs)) {
-            error_setg(errp, "Device '%s' is not encrypted",
-                      bdrv_get_device_name(bs));
+            error_setg(errp, "Node '%s' is not encrypted",
+                      bdrv_get_device_or_node_name(bs));
         } else if (bdrv_set_key(bs, key) < 0) {
             error_set(errp, QERR_INVALID_PASSWORD);
         }
@@ -3833,7 +3833,7 @@
         if (bdrv_key_required(bs)) {
             error_set(errp, ERROR_CLASS_DEVICE_ENCRYPTED,
                       "'%s' (%s) is encrypted",
-                      bdrv_get_device_name(bs),
+                      bdrv_get_device_or_node_name(bs),
                       bdrv_get_encrypted_filename(bs));
         }
     }
@@ -5633,8 +5633,8 @@
     if (!QLIST_EMPTY(&bs->op_blockers[op])) {
         blocker = QLIST_FIRST(&bs->op_blockers[op]);
         if (errp) {
-            error_setg(errp, "Device '%s' is busy: %s",
-                       bdrv_get_device_name(bs),
+            error_setg(errp, "Node '%s' is busy: %s",
+                       bdrv_get_device_or_node_name(bs),
                        error_get_pretty(blocker->reason));
         }
         return true;