Re: [RFC 1/2] ext3: enlarge blocksize and fix rec_len overflow

Hi Andreas,

Andreas Dilger wrote:
> 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.  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.

Then why not introduce a little symmetry by making max rec_len 2**15 and
treat big directory blocks as an array of smaller ones?  I dimly recall
the page-cache oriented Ext2 dir code already does this.

Regards,

Daniel