Re: floppy driver 2.6.3 question

[Peter T. Breuer]

"Also sprach Jens Axboe:"
> > The floppy driver doesn't notice if the revalidation bio failed or not,
> > btw (and I don't see an easy way of telling, hence my questions as to
> > what the bi_size and bytes_done "really" mean - I can return them).  I
> > suppose it can tell via the drive hardware what the state is. I also
> > suppose reading the first block somehow triggers some kind of partition
> > revision or other magic?
> 
> One way would be ala the attached, see how bio_endio() clears
> BIO_UPTODATE on error.

Very good. Applied. Thanks!

(do get_bio(&bio) before submit_bio(&bio) and do put_bio(&bio)
afterwards and examine bio.flags&BIO_UPTODATE on return from
wait_for_completion between the two).

> > know.  128 requests have just previously been errored due to readahead
> > and the check_media_changed result setting the driver request function
> > to error out requests.  Perhaps we have run out of requests (they're
> > all put_ as far as I can see). Maybe the block layers get tired of
> > talking to a device that errors requests. I'm just feeling my way!
> > Any wild ideas are welcome!
> 
> If the 129th request fails, then that's a pretty good clue that you
> aren't getting the requests freed. Perhaps you are overwriting something
> in the request after allocating it? Always mask change ->flags (don't
> just set it), and don't overwrite ->rl.

Good idea. rl is inviolate, but I set at least |=REQ_NOMERGE sometimes
on flags. And I pass ioctl information in fake requests by setting
the bit just beyond the edge of those currently used (__REQ_BITS) to
indicate its an ioctl and treating it specially in end request. Maybe
on error I forgot to remove the extra bit before doing put_blk_request
..

WIll look.

Thanks again.

Peter
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