Re: [Ext2-devel] [RFC 1/2] ext3: enlarge blocksize and fix rec_lenoverflow

["Takashi Sato" <sho@tnes.nec.co.jp>]

Hi,

> On Jun 28, 2006  17:50 +0200, Johann Lombardi wrote:
>> ext2/ext3_dir_entry_2 has a 16-bit entry(rec_len) and it would overflow
>> with 64KB blocksize.  This patch prevent from overflow by limiting
>> rec_len to 65532.
> 
> Having a max rec_len of 65532 is rather unfortunate, since the dir
> blocks always need to filled with dir entries.

Oh, that's right.

> 65536 - 65532 = 4, and
> the minimum ext3_dir_entry size is 8 bytes.  I would instead make this
> maybe 64 bytes less so that there is room for a filename in the "tail"
> dir_entry.

What does "64 bytes" mean?
Do you mean that the following dummy entry should be added
at the tail of the directory block?

struct ext3_dir_entry_2 {
 __le32 inode   = 0
 __le16 rec_len = 16
 __u8 name_len  = 4
 __u8 file_type = 0
 char name      = "dir_end"
};

Cheers, sho