Re: [PATCH 1/2] [md/bitmap] md_bitmap_read_sb use wrong bitmap blocks

["heming.zhao@suse.com" <heming.zhao@suse.com>]

very sorry for my mistake.

the patch should be change from:
```
-		sector_div(bm_blocks,
+		DIV_ROUND_UP_SECTOR_T(bm_blocks,
   			   bitmap->mddev->bitmap_info.chunksize >> 9);
```

to
```
-               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));
```

If my patch would be accepted, I will send v2 patch including above lines.


On 10/4/20 12:11 AM, Zhao Heming wrote:
> 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>
> ---
>   drivers/md/md-bitmap.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c
> index 593fe15..1efd2b4 100644
> --- a/drivers/md/md-bitmap.c
> +++ b/drivers/md/md-bitmap.c
> @@ -605,7 +605,7 @@ static int md_bitmap_read_sb(struct bitmap *bitmap)
>   	if (bitmap->cluster_slot >= 0) {
>   		sector_t bm_blocks = bitmap->mddev->resync_max_sectors;
>   
> -		sector_div(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);
>