Signed-off-by: Sergei Shtepa <sergei.sht...@veeam.com>
---
 drivers/md/dm-snap.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 11890db71f3f..81e8e3bb6d25 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -2685,11 +2685,18 @@ static int origin_map(struct dm_target *ti, struct bio 
*bio)
        if (bio_data_dir(bio) != WRITE)
                return DM_MAPIO_REMAPPED;
 
-       available_sectors = o->split_boundary -
-               ((unsigned)bio->bi_iter.bi_sector & (o->split_boundary - 1));
+       /*
+        * If no snapshot is connected to origin, then split_boundary
+        * will be set to zero. In this case, we don't need to split a bio.
+        */
+       if (o->split_boundary) {
+               available_sectors = o->split_boundary -
+                       ((unsigned int)bio->bi_iter.bi_sector &
+                               (o->split_boundary - 1));
 
-       if (bio_sectors(bio) > available_sectors)
-               dm_accept_partial_bio(bio, available_sectors);
+               if (bio_sectors(bio) > available_sectors)
+                       dm_accept_partial_bio(bio, available_sectors);
+       }
 
        /* Only tell snapshots if this is a write */
        return do_origin(o->dev, bio, true);
-- 
2.20.1

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