1 files changed, 93 insertions, 0 deletions
diff --git a/include/block/block-copy.h b/include/block/block-copy.h
new file mode 100644
index 0000000000..e2e135ff1b
--- /dev/null
+++ b/include/block/block-copy.h
@@ -0,0 +1,93 @@
+/*
+ * block_copy API
+ *
+ * Copyright (C) 2013 Proxmox Server Solutions
+ * Copyright (c) 2019 Virtuozzo International GmbH.
+ *
+ * Authors:
+ *  Dietmar Maurer (dietmar@proxmox.com)
+ *  Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef BLOCK_COPY_H
+#define BLOCK_COPY_H
+
+#include "block/block.h"
+
+typedef struct BlockCopyInFlightReq {
+    int64_t start_byte;
+    int64_t end_byte;
+    QLIST_ENTRY(BlockCopyInFlightReq) list;
+    CoQueue wait_queue; /* coroutines blocked on this request */
+} BlockCopyInFlightReq;
+
+typedef void (*ProgressBytesCallbackFunc)(int64_t bytes, void *opaque);
+typedef void (*ProgressResetCallbackFunc)(void *opaque);
+typedef struct BlockCopyState {
+    /*
+     * BdrvChild objects are not owned or managed by block-copy. They are
+     * provided by block-copy user and user is responsible for appropriate
+     * permissions on these children.
+     */
+    BdrvChild *source;
+    BdrvChild *target;
+    BdrvDirtyBitmap *copy_bitmap;
+    int64_t cluster_size;
+    bool use_copy_range;
+    int64_t copy_range_size;
+    uint64_t len;
+    QLIST_HEAD(, BlockCopyInFlightReq) inflight_reqs;
+
+    BdrvRequestFlags write_flags;
+
+    /*
+     * skip_unallocated:
+     *
+     * Used by sync=top jobs, which first scan the source node for unallocated
+     * areas and clear them in the copy_bitmap.  During this process, the bitmap
+     * is thus not fully initialized: It may still have bits set for areas that
+     * are unallocated and should actually not be copied.
+     *
+     * This is indicated by skip_unallocated.
+     *
+     * In this case, block_copy() will query the source’s allocation status,
+     * skip unallocated regions, clear them in the copy_bitmap, and invoke
+     * block_copy_reset_unallocated() every time it does.
+     */
+    bool skip_unallocated;
+
+    /* progress_bytes_callback: called when some copying progress is done. */
+    ProgressBytesCallbackFunc progress_bytes_callback;
+
+    /*
+     * progress_reset_callback: called when some bytes reset from copy_bitmap
+     * (see @skip_unallocated above). The callee is assumed to recalculate how
+     * many bytes remain based on the dirty bit count of copy_bitmap.
+     */
+    ProgressResetCallbackFunc progress_reset_callback;
+    void *progress_opaque;
+} BlockCopyState;
+
+BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
+                                     int64_t cluster_size,
+                                     BdrvRequestFlags write_flags,
+                                     Error **errp);
+
+void block_copy_set_callbacks(
+        BlockCopyState *s,
+        ProgressBytesCallbackFunc progress_bytes_callback,
+        ProgressResetCallbackFunc progress_reset_callback,
+        void *progress_opaque);
+
+void block_copy_state_free(BlockCopyState *s);
+
+int64_t block_copy_reset_unallocated(BlockCopyState *s,
+                                     int64_t offset, int64_t *count);
+
+int coroutine_fn block_copy(BlockCopyState *s, int64_t start, uint64_t bytes,
+                            bool *error_is_read);
+
+#endif /* BLOCK_COPY_H */