Hi, On Mon 21-06-10 08:29:06, Theodore Ts'o wrote: > I've created an updated quota design document here: > > https://ext4.wiki.kernel.org/index.php/Design_For_1st_Class_Quota_in_Ext4 > > No major changes from last time. > > One new thing is a proposed (optional) change to the quota format, > to use the 32-bit dqpb_pad field in the v2r1 on-disk quota structure as > a 32-bit CRC of the quota entry. This would allow the quota system to > detect corrupted quota entries. Jan, what do you think? It might be reasonable to checksum dquots so that we get closer to all-metadata-are-checksummed state. I'm just thinking whether checksumming each dquot is so useful. For example OCFS2 checksums each quota block. That has an advantage that also quota file tree blocks and headers are protected. Also it's possible to use the generic block checksumming framework in JBD2 for this case. OTOH ext4 seems to have chosen to checksum each group descriptor individually so checksumming each dquot structure would seem more consistent. So I don't have a strong opinion which checksumming scheme should be chosen. I just wanted to point out that there's another reasonable option. Generic quota code can easily handle both (including leaving some bytes at the end of each block for checksums as it does for OCFS2 now). Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
