md: Fix bitmap offset calculations

The calculations of bitmap offset is incorrect with respect to bits to bytes
conversion.

Also, remove an irrelevant duplicate message.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 3 insertions, 4 deletions

diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index ac79fef68143..e98db04eb4f9 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -575,7 +575,9 @@ re_read:
 
                 sector_div(bm_blocks,
                            bitmap->mddev->bitmap_info.chunksize >> 9);
-                bm_blocks = bm_blocks << 3;
+                /* bits to bytes */
+                bm_blocks = ((bm_blocks+7) >> 3) + sizeof(bitmap_super_t);
+                /* to 4k blocks */
                 bm_blocks = DIV_ROUND_UP_SECTOR_T(bm_blocks, 4096);
                 bitmap->mddev->bitmap_info.offset += bitmap->cluster_slot * (bm_blocks << 3);
                 pr_info("%s:%d bm slot: %d offset: %llu\n", __func__, __LINE__,
@@ -672,9 +674,6 @@ out:
                         goto out_no_sb;
                 }
                 bitmap->cluster_slot = md_cluster_ops->slot_number(bitmap->mddev);
-                pr_info("%s:%d bm slot: %d offset: %llu\n", __func__, __LINE__,
-                        bitmap->cluster_slot,
-                        (unsigned long long)bitmap->mddev->bitmap_info.offset);
                 goto re_read;
         }