[PATCH 17/21] block/block-copy: switch to fully set bitmap by default

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

block-copy has a bit inconvenient interface around dirty bitmap: user
should get pointer to it and than set by hand. We do need a possibility
to share the bitmap with backup job.

But default of empty bitmap is strange. Switch to full-set bitmap by
default. This way we will not care about setting dirty bitmap in
copy-before-write filter when publish it so that it can be used in
separate of backup job.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/backup.c     | 16 +++++++---------
 block/block-copy.c |  1 +
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/block/backup.c b/block/backup.c
index 90cca1ca30..706c54fea1 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -233,18 +233,16 @@ static void backup_init_bcs_bitmap(BackupBlockJob *job)
     BdrvDirtyBitmap *bcs_bitmap = block_copy_dirty_bitmap(job->bcs);
 
     if (job->sync_mode == MIRROR_SYNC_MODE_BITMAP) {
+        bdrv_clear_dirty_bitmap(bcs_bitmap, NULL);
         ret = bdrv_dirty_bitmap_merge_internal(bcs_bitmap, job->sync_bitmap,
                                                NULL, true);
         assert(ret);
-    } else {
-        if (job->sync_mode == MIRROR_SYNC_MODE_TOP) {
-            /*
-             * We can't hog the coroutine to initialize this thoroughly.
-             * Set a flag and resume work when we are able to yield safely.
-             */
-            block_copy_set_skip_unallocated(job->bcs, true);
-        }
-        bdrv_set_dirty_bitmap(bcs_bitmap, 0, job->len);
+    } else if (job->sync_mode == MIRROR_SYNC_MODE_TOP) {
+        /*
+         * We can't hog the coroutine to initialize this thoroughly.
+         * Set a flag and resume work when we are able to yield safely.
+         */
+        block_copy_set_skip_unallocated(job->bcs, true);
     }
 
     estimate = bdrv_get_dirty_count(bcs_bitmap);
diff --git a/block/block-copy.c b/block/block-copy.c
index 9020234c6e..4126f7e8cc 100644
--- a/block/block-copy.c
+++ b/block/block-copy.c
@@ -296,6 +296,7 @@ BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
         return NULL;
     }
     bdrv_disable_dirty_bitmap(copy_bitmap);
+    bdrv_set_dirty_bitmap(copy_bitmap, 0, bdrv_dirty_bitmap_size(copy_bitmap));
 
     /*
      * Why we always set BDRV_REQ_SERIALISING write flag:
-- 
2.29.2