Re: [PATCH] log replay should not overwrite newer ondisk inodes

Timothy Shimmin
2007-08-30T08:51:37Z

Timothy Shimmin wrote:
>>> But I'm not sure this is an error...
>>> Hmmmm...I'm a bit confused.
>>> So you are _almost_ combining an error check with a flushiter check?
>>> If one buffer is an inode magic# and the other isn't then we
>>> have an error right - and could report it - but we are not doing
>>> that here.
>> Not exactly. If what's on disk is not an inode but the log item is
>> then that could be because we haven't written the inode to disk yet
>> and we need to perform recovery.
> Yeah, I was thinking about that afterward.
> The item's format which gives the blk# for the buf to read could
> be a block which hasn't been used for an inode yet.
>
Well, if what's on disk is not an inode but some other data
and it happens to have the inode magic# which is remotely possible,
then we are making a bad assumption.
i.e. if we're not sure what the block/buffer should be, then testing the
MAGIC# isn't a guarantee it's an inode then.
Well not for the freeing of inode clusters case I would assume.
Or am I missing something?

--Tim