cutils: add qemu_pstrcmp0()

[qemu.git] / block / snapshot.c

diff --git a/block/snapshot.c b/block/snapshot.c
index 85855995793bf4063e61290c643b03799e8c70f2..3218a542df833170b4da85f91c726131651d6894 100644 (file)
--- a/block/snapshot.c
+++ b/block/snapshot.c
@@ -25,9 +25,12 @@
 #include "qemu/osdep.h"
 #include "block/snapshot.h"
 #include "block/block_int.h"
+#include "block/qdict.h"
 #include "qapi/error.h"
+#include "qapi/qmp/qdict.h"
 #include "qapi/qmp/qerror.h"
 #include "qapi/qmp/qstring.h"
+#include "qemu/option.h"
 
 QemuOptsList internal_snapshot_opts = {
     .name = "snapshot",
@@ -182,25 +185,16 @@ int bdrv_snapshot_goto(BlockDriverState *bs,
 {
     BlockDriver *drv = bs->drv;
     int ret, open_ret;
-    int64_t len;
 
     if (!drv) {
         error_setg(errp, "Block driver is closed");
         return -ENOMEDIUM;
     }
 
-    len = bdrv_getlength(bs);
-    if (len < 0) {
-        error_setg_errno(errp, -len, "Cannot get block device size");
-        return len;
+    if (!QLIST_EMPTY(&bs->dirty_bitmaps)) {
+        error_setg(errp, "Device has active dirty bitmaps");
+        return -EBUSY;
     }
-    /* We should set all bits in all enabled dirty bitmaps, because dirty
-     * bitmaps reflect active state of disk and snapshot switch operation
-     * actually dirties active state.
-     * TODO: It may make sense not to set all bits but analyze block status of
-     * current state and destination snapshot and do not set bits corresponding
-     * to both-zero or both-unallocated areas. */
-    bdrv_set_dirty(bs, 0, len);
 
     if (drv->bdrv_snapshot_goto) {
         ret = drv->bdrv_snapshot_goto(bs, snapshot_id);
@@ -221,16 +215,18 @@ int bdrv_snapshot_goto(BlockDriverState *bs,
         bdrv_ref(file);
 
         qdict_extract_subqdict(options, &file_options, "file.");
-        QDECREF(file_options);
+        qobject_unref(file_options);
         qdict_put_str(options, "file", bdrv_get_node_name(file));
 
-        drv->bdrv_close(bs);
+        if (drv->bdrv_close) {
+            drv->bdrv_close(bs);
+        }
         bdrv_unref_child(bs, bs->file);
         bs->file = NULL;
 
         ret = bdrv_snapshot_goto(file, snapshot_id, errp);
         open_ret = drv->bdrv_open(bs, options, bs->open_flags, &local_err);
-        QDECREF(options);
+        qobject_unref(options);
         if (open_ret < 0) {
             bdrv_unref(file);
             bs->drv = NULL;