On Mon, 12 Mar 2012 11:04:12 +0800 Shaohua Li <shli@fusionio.com> wrote:

> The patches add TRIM support for raid linear/0/1/10. I'll add TRIM support for
> raid 4/5/6 later. The implementation is pretty straightforward and
> self-explained.
> 
> Thanks,
> Shaohua

Thanks.
They look mostly OK.

In raid0.c, I think you'll need to change

		/* Sanity check -- queue functions should prevent this happening */
		if (bio->bi_vcnt != 1 ||
		    bio->bi_idx != 0)
			goto bad_map;

to also allow for 'bi_vcnt == 0' like you did in bio_split.

Also I wonder about handling failure in RAID1.
I think the code will currently treat it like a write error, and
maybe record a bad block (then fail the device is writing the badblock
record fails). Is that what were want?

And of course resync/recovery will mess up the discarded sector information,
so this isn't a complete solution for RAID1.  But  it is a reasonable start.

Thanks,
NeilBrown