[PATCH 4/4] erofs-utils: dump: add some superblock fields

[Gao Xiang]

On 2023/6/9 16:50, Guo Xuenan via Linux-erofs wrote:
> dump.erofs show compression algorithms and sb_extslots,
> and update feature information.
> 
> The proposed super block info is shown as below:
> Filesystem magic number:                      0xE0F5E1E2
> Filesystem blocks:                            4624
> Filesystem inode metadata start block:        0
> Filesystem shared xattr metadata start block: 0
> Filesystem root nid:                          37
> Filesystem compr_algs:                        lz4, lz4hc, lzma
> Filesystem sb_extslots:                       0
> Filesystem inode count:                       6131
> Filesystem created:                           Wed Jun  7 17:15:44 2023
> Filesystem features:                          sb_csum mtime 0padding compr_cfgs big_pcluster
> Filesystem UUID:                              not available
> 
> Signed-off-by: Guo Xuenan <guoxuenan at huawei.com>
> ---
>   dump/main.c              | 11 +++++++++++
>   include/erofs/internal.h |  1 +
>   lib/super.c              |  5 +++++
>   3 files changed, 17 insertions(+)
> 
> diff --git a/dump/main.c b/dump/main.c
> index ae1ffa0..2cb412d 100644
> --- a/dump/main.c
> +++ b/dump/main.c
> @@ -94,12 +94,14 @@ static struct erofsdump_feature feature_lists[] = {
>   	{ true, EROFS_FEATURE_COMPAT_SB_CHKSUM, "sb_csum" },
>   	{ true, EROFS_FEATURE_COMPAT_MTIME, "mtime" },
>   	{ false, EROFS_FEATURE_INCOMPAT_ZERO_PADDING, "0padding" },
> +	{ false, EROFS_FEATURE_INCOMPAT_COMPR_CFGS, "compr_cfgs" },
>   	{ false, EROFS_FEATURE_INCOMPAT_BIG_PCLUSTER, "big_pcluster" },
>   	{ false, EROFS_FEATURE_INCOMPAT_CHUNKED_FILE, "chunked_file" },
>   	{ false, EROFS_FEATURE_INCOMPAT_DEVICE_TABLE, "device_table" },
>   	{ false, EROFS_FEATURE_INCOMPAT_ZTAILPACKING, "ztailpacking" },
>   	{ false, EROFS_FEATURE_INCOMPAT_FRAGMENTS, "fragments" },
>   	{ false, EROFS_FEATURE_INCOMPAT_DEDUPE, "dedupe" },
> +	{ false, EROFS_FEATURE_INCOMPAT_XATTR_PREFIXES, "xattr_prefixes" },
>   };
>   
>   static int erofsdump_readdir(struct erofs_dir_context *ctx);
> @@ -609,6 +611,15 @@ static void erofsdump_show_superblock(void)
>   	if (erofs_sb_has_fragments() && sbi.packed_nid > 0)
>   		fprintf(stdout, "Filesystem packed nid:                        %llu\n",
>   			sbi.packed_nid | 0ULL);
> +	if (erofs_sb_has_compr_cfgs()) {
> +		fprintf(stdout, "Filesystem compr_algs:                        ");
> +		zerofs_print_supported_compressors(stdout, sbi.available_compr_algs);
> +	} else {
> +		fprintf(stdout, "Filesystem lz4_max_dist:                      %u\n",

lz4_max_distance is better, let's keep the on-disk full name.