[Qemu-devel] [RFC PATCH 10/14] allow the backing image access the origin BlockDriverState

[Wen Congyang]

Block replication needs this feature.

Signed-off-by: Wen Congyang <address@hidden>
Signed-off-by: zhanghailiang <address@hidden>
Signed-off-by: Gonglei <address@hidden>
---
 block.c                   | 2 ++
 include/block/block_int.h | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/block.c b/block.c
index a7a8932..067c44b 100644
--- a/block.c
+++ b/block.c
@@ -1181,6 +1181,7 @@ void bdrv_set_backing_hd(BlockDriverState *bs, 
BlockDriverState *backing_hd)
     if (bs->backing_hd) {
         assert(bs->backing_blocker);
         bdrv_op_unblock_all(bs->backing_hd, bs->backing_blocker);
+        bs->backing_hd->origin_file = NULL;
     } else if (backing_hd) {
         error_setg(&bs->backing_blocker,
                    "device is used as backing hd of '%s'",
@@ -1193,6 +1194,7 @@ void bdrv_set_backing_hd(BlockDriverState *bs, 
BlockDriverState *backing_hd)
         bs->backing_blocker = NULL;
         goto out;
     }
+    backing_hd->origin_file = bs;
     bs->open_flags &= ~BDRV_O_NO_BACKING;
     pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_hd->filename);
     pstrcpy(bs->backing_format, sizeof(bs->backing_format),
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 603f704..9be13a8 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -360,6 +360,8 @@ struct BlockDriverState {
     char exact_filename[PATH_MAX];
 
     BlockDriverState *backing_hd;
+    /* used by backing image */
+    BlockDriverState *origin_file;
     BlockDriverState *file;
 
     NotifierList close_notifiers;
-- 
2.1.0