[Qemu-block] [PATCH COLO-Block v6 07/16] Add new block driver interface to connect/disconnect the remote target

[Wen Congyang]

In some cases, we want to connect/disconnect the remote target when
we need, not in bdrv_open()/bdrv_close().

Signed-off-by: Wen Congyang <address@hidden>
Signed-off-by: zhanghailiang <address@hidden>
Signed-off-by: Gonglei <address@hidden>
---
 block.c                   | 24 ++++++++++++++++++++++++
 include/block/block.h     |  3 +++
 include/block/block_int.h |  3 +++
 3 files changed, 30 insertions(+)

diff --git a/block.c b/block.c
index 0b41af4..59071d4 100644
--- a/block.c
+++ b/block.c
@@ -4400,3 +4400,27 @@ BlockAcctStats *bdrv_get_stats(BlockDriverState *bs)
 {
     return &bs->stats;
 }
+
+void bdrv_connect(BlockDriverState *bs, Error **errp)
+{
+    BlockDriver *drv = bs->drv;
+
+    if (drv && drv->bdrv_connect) {
+        drv->bdrv_connect(bs, errp);
+    } else if (bs->file) {
+        bdrv_connect(bs->file, errp);
+    } else {
+        error_setg(errp, "this feature or command is not currently supported");
+    }
+}
+
+void bdrv_disconnect(BlockDriverState *bs)
+{
+    BlockDriver *drv = bs->drv;
+
+    if (drv && drv->bdrv_disconnect) {
+        drv->bdrv_disconnect(bs);
+    } else if (bs->file) {
+        bdrv_disconnect(bs->file);
+    }
+}
diff --git a/include/block/block.h b/include/block/block.h
index 7cdb569..2c2a0cc 100644
--- a/include/block/block.h
+++ b/include/block/block.h
@@ -606,4 +606,7 @@ void bdrv_flush_io_queue(BlockDriverState *bs);
 
 BlockAcctStats *bdrv_get_stats(BlockDriverState *bs);
 
+void bdrv_connect(BlockDriverState *bs, Error **errp);
+void bdrv_disconnect(BlockDriverState *bs);
+
 #endif
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 87fe89a..a3e5372 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -290,6 +290,9 @@ struct BlockDriver {
      */
     int (*bdrv_probe_geometry)(BlockDriverState *bs, HDGeometry *geo);
 
+    void (*bdrv_connect)(BlockDriverState *bs, Error **errp);
+    void (*bdrv_disconnect)(BlockDriverState *bs);
+
     QLIST_ENTRY(BlockDriver) list;
 };
 
-- 
2.4.3