[PATCH] erofs: fix wrong address in erofs_get_block

[Gao Xiang]

Hi Jianan,

On Tue, Dec 08, 2020 at 04:47:50PM +0800, Huang Jianan wrote:
> iblock indicates the number of i_blkbits-sized blocks rather than
> sectors, fix it.
> 
> If the data has a disk mapping, map_bh should be used to read the
> correct data from the device.
> 
> Fixes: 9da681e017a3 ("staging: erofs: support bmap")
> Signed-off-by: Huang Jianan <huangjianan at oppo.com>
> Signed-off-by: Guo Weichao <guoweichao at oppo.com>
> ---
>  fs/erofs/data.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/erofs/data.c b/fs/erofs/data.c
> index 347be146884c..1415fee10180 100644
> --- a/fs/erofs/data.c
> +++ b/fs/erofs/data.c
> @@ -316,7 +316,7 @@ static int erofs_get_block(struct inode *inode, sector_t iblock,
>  			   struct buffer_head *bh, int create)
>  {
>  	struct erofs_map_blocks map = {
> -		.m_la = iblock << 9,
> +		.m_la = iblock << blknr_to_addr(iblock),

Sorry I don't get the point although I think the problem may exist....
I mean is that correct? since it equals to iblocks << (iblock * EROFS_BLKSIZE) ....

Thanks,
Gao Xiang


>  	};
>  	int err;
>  
> @@ -325,7 +325,7 @@ static int erofs_get_block(struct inode *inode, sector_t iblock,
>  		return err;
>  
>  	if (map.m_flags & EROFS_MAP_MAPPED)
> -		bh->b_blocknr = erofs_blknr(map.m_pa);
> +		map_bh(bh, inode->i_sb, erofs_blknr(map.m_pa));
>  
>  	return err;
>  }
> -- 
> 2.25.1
>