Since previous commit, copy_range supports max_transfer, so we don't
need to handle it by hand.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/backup.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/block/backup.c b/block/backup.c
index c6a3b2b7bb..228ba9423c 100644
--- a/block/backup.c
+++ b/block/backup.c
@@ -54,7 +54,6 @@ typedef struct BackupBlockJob {
     QLIST_HEAD(, CowRequest) inflight_reqs;
 
     bool use_copy_range;
-    int64_t copy_range_size;
 
     BdrvRequestFlags write_flags;
     bool initializing_bitmap;
@@ -156,12 +155,11 @@ static int coroutine_fn backup_cow_with_offload(BackupBlockJob *job,
     int ret;
     int nr_clusters;
     BlockBackend *blk = job->common.blk;
-    int nbytes;
+    int nbytes = end - start;
     int read_flags = is_write_notifier ? BDRV_REQ_NO_SERIALISING : 0;
 
-    assert(QEMU_IS_ALIGNED(job->copy_range_size, job->cluster_size));
+    assert(end - start < INT_MAX);
     assert(QEMU_IS_ALIGNED(start, job->cluster_size));
-    nbytes = MIN(job->copy_range_size, end - start);
     nr_clusters = DIV_ROUND_UP(nbytes, job->cluster_size);
     bdrv_reset_dirty_bitmap(job->copy_bitmap, start,
                             job->cluster_size * nr_clusters);
@@ -756,11 +754,6 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
     job->copy_bitmap = copy_bitmap;
     copy_bitmap = NULL;
     job->use_copy_range = !compress; /* compression isn't supported for it */
-    job->copy_range_size = MIN_NON_ZERO(blk_get_max_transfer(job->common.blk),
-                                        blk_get_max_transfer(job->target));
-    job->copy_range_size = MAX(job->cluster_size,
-                               QEMU_ALIGN_UP(job->copy_range_size,
-                                             job->cluster_size));
 
     /* Required permissions are already taken with target's blk_new() */
     block_job_add_bdrv(&job->common, "target", target, 0, BLK_PERM_ALL,
-- 
2.18.0

On 09.08.19 17:32, Vladimir Sementsov-Ogievskiy wrote:
> Since previous commit, copy_range supports max_transfer, so we don't
> need to handle it by hand.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  block/backup.c | 11 ++---------
>  1 file changed, 2 insertions(+), 9 deletions(-)

Reviewed-by: Max Reitz <mreitz@redhat.com>