From: Zhao Heming <heming.zhao@suse.com>
Date: Mon, 5 Oct 2020 16:00:23 +0000 (+0800)
Subject: md/bitmap: md_bitmap_read_sb uses wrong bitmap blocks
X-Git-Tag: v5.10-rc1~165^2^2~4
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a913096decbf4101271e7d87b9affb1454bb7676;p=thirdparty%2Fkernel%2Flinux.git

md/bitmap: md_bitmap_read_sb uses wrong bitmap blocks

The patched code is used to get chunks number, should use round-up div
to replace current sector_div. The same code is in md_bitmap_resize():
```
chunks = DIV_ROUND_UP_SECTOR_T(blocks, 1 << chunkshift);
```

Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
---

diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
index 55b757a223a4f..cd9a12ca281d3 100644
--- a/drivers/md/md-bitmap.c
+++ b/drivers/md/md-bitmap.c
@@ -606,8 +606,8 @@ re_read:
 	if (bitmap->cluster_slot >= 0) {
 		sector_t bm_blocks = bitmap->mddev->resync_max_sectors;
 
-		sector_div(bm_blocks,
-			   bitmap->mddev->bitmap_info.chunksize >> 9);
+		bm_blocks = DIV_ROUND_UP_SECTOR_T(bm_blocks,
+			   (bitmap->mddev->bitmap_info.chunksize >> 9));
 		/* bits to bytes */
 		bm_blocks = ((bm_blocks+7) >> 3) + sizeof(bitmap_super_t);
 		/* to 4k blocks */