Re: [PATCH] only irq-safe atomic ops

Steve Lord
2002-02-25T19:49:31Z

On Mon, 2002-02-25 at 13:42, Andrew Morton wrote:
> Stephen Lord wrote:
> >
> > Yep, bio just made it easier to get larger requests.
> >
>
> Which promptly go kersplat when you feed them into
> submit_bio():
>
> BUG_ON(bio_sectors(bio) > q->max_sectors);
>
> Given that I'm hand-rolling a monster bio, I need to know
> when to wrap it up and send it off, to avoid creating a bio
> which is larger than the target device will accept. I'm currently
> using the below patch. Am I right that this is missing API
> functionality, or did I miss something?
>

I don't run into that one, but probably because I limit xfs to
use BIO_MAX_SECTORS, take a look at ll_rw_kio to see how that
splits things up. This of course does not take into account
any further restriction in an underlying queue.

Steve

--

Steve Lord voice: +1-651-683-3511
Principal Engineer, Filesystem Software email: lord@sgi.com