On 7/8/25 10:35, Gao Xiang wrote:
>
>
> On 2025/7/8 10:30, Hongbo Li wrote:
>>
>>
>> On 2025/7/7 16:47, Chao Yu wrote:
>>> All below functions will do sanity check on m->type, let's move sanity
>>> check to z_erofs_load_compact_lcluster() for cleanup.
>>> - z_erofs_map_blocks_fo
>>> - z_erofs_get_extent_compressedlen
>>> - z_erofs_get_extent_decompressedlen
>>> - z_erofs_extent_lookback
>>>
>>> Signed-off-by: Chao Yu <c...@kernel.org>
>>> ---
>>> fs/erofs/zmap.c | 60 ++++++++++++++++++-------------------------------
>>> 1 file changed, 22 insertions(+), 38 deletions(-)
>>>
>>> diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
>>> index 0bebc6e3a4d7..e530b152e14e 100644
>>> --- a/fs/erofs/zmap.c
>>> +++ b/fs/erofs/zmap.c
>>> @@ -240,6 +240,13 @@ static int z_erofs_load_compact_lcluster(struct
>>> z_erofs_maprecorder *m,
>>> static int z_erofs_load_lcluster_from_disk(struct z_erofs_maprecorder *m,
>>> unsigned int lcn, bool lookahead)
>>> {
>>> + if (m->type >= Z_EROFS_LCLUSTER_TYPE_MAX) {
>>> + erofs_err(m->inode->i_sb, "unknown type %u @ lcn %u of nid %llu",
>>> + m->type, lcn, EROFS_I(m->inode)->nid);
>>> + DBG_BUGON(1);
>>> + return -EOPNOTSUPP;
>>> + }
>>> +
>>
>> Hi, Chao,
>>
>> After moving the condition in here, there is no need to check in
>> z_erofs_extent_lookback, z_erofs_get_extent_compressedlen and
>> z_erofs_get_extent_decompressedlen. Because in z_erofs_map_blocks_fo,
>> the condition has been checked in before. Right?
>
> I've replied some similar question.
>
> Because z_erofs_get_extent_compressedlen and
> z_erofs_get_extent_decompressedlen()
> use the different lcn (lcluster) against z_erofs_map_blocks_fo().
>
> So if a new lcn(lcluster number) is loaded, we'd check if the type is valid.
Yeah, Xiang has noticed that previously [1], the case is as below, so we'd
better check the
condition in z_erofs_load_compact_lcluster() rather than
z_erofs_map_blocks_fo():
- z_erofs_extent_lookback
- z_erofs_load_lcluster_from_disk
- z_erofs_load_full_lcluster
: m->type = advise & Z_EROFS_LI_LCLUSTER_TYPE_MASK;
- z_erofs_load_compact_lcluster
: m->type = type;
[1]
https://lore.kernel.org/linux-erofs/04050888-7abf-40fa-98d6-6215b8ba9...@kernel.org/
Thanks,
>
> Thanks,
> Gao Xiang
>
>
