Re: [PATCH v2 2/2] staging: erofs: fix i_blocks calculation

[Chao Yu]

On 2019/5/28 10:36, Gao Xiang wrote:
> For compressed files, i_blocks should not be calculated
> by using i_size. i_u.compressed_blocks is used instead.
> 
> In addition, i_blocks was miscalculated for non-compressed
> files previously, fix it as well.
> 
> Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
> ---
> change log v2:
>  - fix description in commit message
>  - fix to 'inode->i_blocks = nblks << LOG_SECTORS_PER_BLOCK'
> 
> Thanks,
> Gao Xiang
> 
>  drivers/staging/erofs/inode.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/staging/erofs/inode.c b/drivers/staging/erofs/inode.c
> index 8da144943ed6..6e67e018784e 100644
> --- a/drivers/staging/erofs/inode.c
> +++ b/drivers/staging/erofs/inode.c
> @@ -20,6 +20,7 @@ static int read_inode(struct inode *inode, void *data)
>  	struct erofs_vnode *vi = EROFS_V(inode);
>  	struct erofs_inode_v1 *v1 = data;
>  	const unsigned int advise = le16_to_cpu(v1->i_advise);
> +	erofs_blk_t nblks = 0;
>  
>  	vi->data_mapping_mode = __inode_data_mapping(advise);
>  
> @@ -60,6 +61,10 @@ static int read_inode(struct inode *inode, void *data)
>  			le32_to_cpu(v2->i_ctime_nsec);
>  
>  		inode->i_size = le64_to_cpu(v2->i_size);
> +
> +		/* total blocks for compressed files */
> +		if (vi->data_mapping_mode == EROFS_INODE_LAYOUT_COMPRESSION)
> +			nblks = v2->i_u.compressed_blocks;

Xiang,

It needs to use le32_to_cpu(). ;)

>  	} else if (__inode_version(advise) == EROFS_INODE_LAYOUT_V1) {
>  		struct erofs_sb_info *sbi = EROFS_SB(inode->i_sb);
>  
> @@ -90,6 +95,8 @@ static int read_inode(struct inode *inode, void *data)
>  			sbi->build_time_nsec;
>  
>  		inode->i_size = le32_to_cpu(v1->i_size);
> +		if (vi->data_mapping_mode == EROFS_INODE_LAYOUT_COMPRESSION)
> +			nblks = v1->i_u.compressed_blocks;

Ditto.

Thanks,

>  	} else {
>  		errln("unsupported on-disk inode version %u of nid %llu",
>  		      __inode_version(advise), vi->nid);
> @@ -97,8 +104,11 @@ static int read_inode(struct inode *inode, void *data)
>  		return -EIO;
>  	}
>  
> -	/* measure inode.i_blocks as the generic filesystem */
> -	inode->i_blocks = ((inode->i_size - 1) >> 9) + 1;
> +	if (!nblks)
> +		/* measure inode.i_blocks as generic filesystems */
> +		inode->i_blocks = roundup(inode->i_size, EROFS_BLKSIZ) >> 9;
> +	else
> +		inode->i_blocks = nblks << LOG_SECTORS_PER_BLOCK;
>  	return 0;
>  }
>  
>