[PATCH v2] erofs-utils: avoid the potentially wrong m_plen for big pcluster

[Gao Xiang]

On Mon, Oct 31, 2022 at 10:26:53AM +0800, Yue Hu wrote:
> From: Yue Hu <huyue2 at coolpad.com>
> 
> Keep in sync with the kernel commit 0d53d2e882f9 ("erofs: avoid the
> potentially wrong m_plen for big pcluster").
> 
> Signed-off-by: Yue Hu <huyue2 at coolpad.com>

Reviewed-by: Gao Xiang <hsiangkao at linux.alibaba.com>

Thanks,
Gao Xiang

> ---
> v2: rebase on latest dev branch
> 
>  lib/zmap.c | 16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/lib/zmap.c b/lib/zmap.c
> index 1c6706a..89e9da1 100644
> --- a/lib/zmap.c
> +++ b/lib/zmap.c
> @@ -115,7 +115,7 @@ struct z_erofs_maprecorder {
>  	u8  type, headtype;
>  	u16 clusterofs;
>  	u16 delta[2];
> -	erofs_blk_t pblk, compressedlcs;
> +	erofs_blk_t pblk, compressedblks;
>  	erofs_off_t nextpackoff;
>  	bool partialref;
>  };
> @@ -172,7 +172,7 @@ static int legacy_load_cluster_from_disk(struct z_erofs_maprecorder *m,
>  				DBG_BUGON(1);
>  				return -EFSCORRUPTED;
>  			}
> -			m->compressedlcs = m->delta[0] &
> +			m->compressedblks = m->delta[0] &
>  				~Z_EROFS_VLE_DI_D0_CBLKCNT;
>  			m->delta[0] = 1;
>  		}
> @@ -274,7 +274,7 @@ static int unpack_compacted_index(struct z_erofs_maprecorder *m,
>  				DBG_BUGON(1);
>  				return -EFSCORRUPTED;
>  			}
> -			m->compressedlcs = lo & ~Z_EROFS_VLE_DI_D0_CBLKCNT;
> +			m->compressedblks = lo & ~Z_EROFS_VLE_DI_D0_CBLKCNT;
>  			m->delta[0] = 1;
>  			return 0;
>  		} else if (i + 1 != (int)vcnt) {
> @@ -471,7 +471,7 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
>  	}
>  
>  	lcn = m->lcn + 1;
> -	if (m->compressedlcs)
> +	if (m->compressedblks)
>  		goto out;
>  
>  	err = z_erofs_load_cluster_from_disk(m, lcn, false);
> @@ -480,7 +480,7 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
>  
>  	/*
>  	 * If the 1st NONHEAD lcluster has already been handled initially w/o
> -	 * valid compressedlcs, which means at least it mustn't be CBLKCNT, or
> +	 * valid compressedblks, which means at least it mustn't be CBLKCNT, or
>  	 * an internal implemenatation error is detected.
>  	 *
>  	 * The following code can also handle it properly anyway, but let's
> @@ -496,12 +496,12 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
>  		 * if the 1st NONHEAD lcluster is actually PLAIN or HEAD type
>  		 * rather than CBLKCNT, it's a 1 lcluster-sized pcluster.
>  		 */
> -		m->compressedlcs = 1;
> +		m->compressedblks = 1 << (lclusterbits - LOG_BLOCK_SIZE);
>  		break;
>  	case Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD:
>  		if (m->delta[0] != 1)
>  			goto err_bonus_cblkcnt;
> -		if (m->compressedlcs)
> +		if (m->compressedblks)
>  			break;
>  		/* fallthrough */
>  	default:
> @@ -511,7 +511,7 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
>  		return -EFSCORRUPTED;
>  	}
>  out:
> -	map->m_plen = m->compressedlcs << lclusterbits;
> +	map->m_plen = m->compressedblks << LOG_BLOCK_SIZE;
>  	return 0;
>  err_bonus_cblkcnt:
>  	erofs_err("bogus CBLKCNT @ lcn %lu of nid %llu",
> -- 
> 2.17.1