[RFC,v4,2/3] block: call the snapshot handlers of the protocol drivers

Commit Message

MORITA Kazutaka May 28, 2010, 2:44 a.m. UTC

None

Patch

diff --git a/block.c b/block.c
index da0dc47..cf80dbf 100644
--- a/block.c
+++ b/block.c
@@ -1697,9 +1697,11 @@  int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
     BlockDriver *drv = bs->drv;
     if (!drv)
         return -ENOMEDIUM;
-    if (!drv->bdrv_save_vmstate)
-        return -ENOTSUP;
-    return drv->bdrv_save_vmstate(bs, buf, pos, size);
+    if (drv->bdrv_save_vmstate)
+        return drv->bdrv_save_vmstate(bs, buf, pos, size);
+    if (bs->file)
+        return bdrv_save_vmstate(bs->file, buf, pos, size);
+    return -ENOTSUP;
 }
 
 int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
@@ -1708,9 +1710,11 @@  int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
     BlockDriver *drv = bs->drv;
     if (!drv)
         return -ENOMEDIUM;
-    if (!drv->bdrv_load_vmstate)
-        return -ENOTSUP;
-    return drv->bdrv_load_vmstate(bs, buf, pos, size);
+    if (drv->bdrv_load_vmstate)
+        return drv->bdrv_load_vmstate(bs, buf, pos, size);
+    if (bs->file)
+        return bdrv_load_vmstate(bs->file, buf, pos, size);
+    return -ENOTSUP;
 }
 
 void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event)
@@ -1734,20 +1738,37 @@  int bdrv_snapshot_create(BlockDriverState *bs,
     BlockDriver *drv = bs->drv;
     if (!drv)
         return -ENOMEDIUM;
-    if (!drv->bdrv_snapshot_create)
-        return -ENOTSUP;
-    return drv->bdrv_snapshot_create(bs, sn_info);
+    if (drv->bdrv_snapshot_create)
+        return drv->bdrv_snapshot_create(bs, sn_info);
+    if (bs->file)
+        return bdrv_snapshot_create(bs->file, sn_info);
+    return -ENOTSUP;
 }
 
 int bdrv_snapshot_goto(BlockDriverState *bs,
                        const char *snapshot_id)
 {
     BlockDriver *drv = bs->drv;
+    int ret, open_ret;
+
     if (!drv)
         return -ENOMEDIUM;
-    if (!drv->bdrv_snapshot_goto)
-        return -ENOTSUP;
-    return drv->bdrv_snapshot_goto(bs, snapshot_id);
+    if (drv->bdrv_snapshot_goto)
+        return drv->bdrv_snapshot_goto(bs, snapshot_id);
+
+    if (bs->file) {
+        drv->bdrv_close(bs);
+        ret = bdrv_snapshot_goto(bs->file, snapshot_id);
+        open_ret = drv->bdrv_open(bs, bs->open_flags);
+        if (open_ret < 0) {
+            bdrv_delete(bs->file);
+            bs->drv = NULL;
+            return open_ret;
+        }
+        return ret;
+    }
+
+    return -ENOTSUP;
 }
 
 int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
@@ -1755,9 +1776,11 @@  int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
     BlockDriver *drv = bs->drv;
     if (!drv)
         return -ENOMEDIUM;
-    if (!drv->bdrv_snapshot_delete)
-        return -ENOTSUP;
-    return drv->bdrv_snapshot_delete(bs, snapshot_id);
+    if (drv->bdrv_snapshot_delete)
+        return drv->bdrv_snapshot_delete(bs, snapshot_id);
+    if (bs->file)
+        return bdrv_snapshot_delete(bs->file, snapshot_id);
+    return -ENOTSUP;
 }
 
 int bdrv_snapshot_list(BlockDriverState *bs,
@@ -1766,9 +1789,11 @@  int bdrv_snapshot_list(BlockDriverState *bs,
     BlockDriver *drv = bs->drv;
     if (!drv)
         return -ENOMEDIUM;
-    if (!drv->bdrv_snapshot_list)
-        return -ENOTSUP;
-    return drv->bdrv_snapshot_list(bs, psn_info);
+    if (drv->bdrv_snapshot_list)
+        return drv->bdrv_snapshot_list(bs, psn_info);
+    if (bs->file)
+        return bdrv_snapshot_list(bs->file, psn_info);
+    return -ENOTSUP;
 }
 
 #define NB_SUFFIXES 4