[Qemu-block] [PATCH 10/18] block/dirty-bitmap: add bdrv_load_dirty_bitmap

[Vladimir Sementsov-Ogievskiy]

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
---
 block/dirty-bitmap.c         | 53 ++++++++++++++++++++++++++++++++++++++++++++
 include/block/block_int.h    |  4 ++++
 include/block/dirty-bitmap.h |  3 +++
 3 files changed, 60 insertions(+)

diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
index 3b7db1d78c..394d4328d5 100644
--- a/block/dirty-bitmap.c
+++ b/block/dirty-bitmap.c
@@ -545,3 +545,56 @@ BdrvDirtyBitmap *bdrv_dirty_bitmap_next(BlockDriverState 
*bs,
     return bitmap == NULL ? QLIST_FIRST(&bs->dirty_bitmaps) :
                             QLIST_NEXT(bitmap, list);
 }
+
+typedef struct BDRVLoadBitmapCo {
+    BlockDriverState *bs;
+    const char *name;
+    Error **errp;
+    BdrvDirtyBitmap *ret;
+    bool in_progress;
+} BDRVLoadBitmapCo;
+
+static void bdrv_load_dity_bitmap_co_entry(void *opaque)
+{
+    BDRVLoadBitmapCo *lbco = opaque;
+    BlockDriver *drv = lbco->bs->drv;
+
+    if (!!drv && !!drv->bdrv_dirty_bitmap_load) {
+        lbco->ret = drv->bdrv_dirty_bitmap_load(lbco->bs, lbco->name,
+                                                lbco->errp);
+    } else if (lbco->bs->file)  {
+        BlockDriverState *bs = lbco->bs;
+        lbco->bs = lbco->bs->file->bs;
+        bdrv_load_dity_bitmap_co_entry(lbco);
+        if (lbco->ret != NULL) {
+            QLIST_REMOVE(lbco->ret, list);
+            QLIST_INSERT_HEAD(&bs->dirty_bitmaps, lbco->ret, list);
+        }
+    } else {
+        lbco->ret = NULL;
+    }
+
+    lbco->in_progress = false;
+}
+
+BdrvDirtyBitmap *bdrv_load_dirty_bitmap(BlockDriverState *bs, const char *name,
+                                        Error **errp)
+{
+    Coroutine *co;
+    BDRVLoadBitmapCo lbco = {
+        .bs = bs,
+        .name = name,
+        .errp = errp,
+        .in_progress = true
+    };
+
+    if (qemu_in_coroutine()) {
+        bdrv_load_dity_bitmap_co_entry(&lbco);
+    } else {
+        co = qemu_coroutine_create(bdrv_load_dity_bitmap_co_entry, &lbco);
+        qemu_coroutine_enter(co);
+        BDRV_POLL_WHILE(bs, lbco.in_progress);
+    }
+
+    return lbco.ret;
+}
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 83a423c580..d3770db539 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -222,6 +222,10 @@ struct BlockDriver {
     int (*bdrv_get_info)(BlockDriverState *bs, BlockDriverInfo *bdi);
     ImageInfoSpecific *(*bdrv_get_specific_info)(BlockDriverState *bs);
 
+    BdrvDirtyBitmap *(*bdrv_dirty_bitmap_load)(BlockDriverState *bs,
+                                               const char *name,
+                                               Error **errp);
+
     int coroutine_fn (*bdrv_save_vmstate)(BlockDriverState *bs,
                                           QEMUIOVector *qiov,
                                           int64_t pos);
diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h
index ff8163ba02..c0c70a8c67 100644
--- a/include/block/dirty-bitmap.h
+++ b/include/block/dirty-bitmap.h
@@ -77,4 +77,7 @@ int64_t bdrv_dirty_bitmap_next_zero(BdrvDirtyBitmap *bitmap, 
uint64_t start);
 BdrvDirtyBitmap *bdrv_dirty_bitmap_next(BlockDriverState *bs,
                                         BdrvDirtyBitmap *bitmap);
 
+BdrvDirtyBitmap *bdrv_load_dirty_bitmap(BlockDriverState *bs, const char *name,
+                                        Error **errp);
+
 #endif
-- 
2.11.0