[Drbd-dev] [fix] drbd uses wrong API for struct bio

[Philipp Reisner]

Am Dienstag, 25. Januar 2005 00:23 schrieb Lars Marowsky-Bree:
> On 2005-01-23T17:16:33, Lars Marowsky-Bree <lmb at suse.de> wrote:
>
> The attached patch fixes drbds useage of bios up some. The proper fix
> would be to indeed change it over to use bio_alloc(), bio_get/put(),
> bio_add_page(), bio_clone (instead of __bio_clone) et cetera, but that
> fix is too complex for the timeframe I have right now.
>
> This should keep drbd-0.7.8 from oopsing not only on the SLES9 SP1
> kernel but also the recent 2.6.10-ac series.
>
> (I could possibly _code_ it, but it'd be too invasive and I'm weary of
> the side-effects it might have and the QA would take too long. There's a
> number of potential cleanups like further consolidation between
> drbd_prepare_req_write/_read and others, but I'd propose to do that for
> the drbd-0.8 branch instead when we can do away with 2.4.)
>
> Please comment on the patch, I'd be grateful.
>

Hi Lars,

the patch looks good so far. I am really happy that you have choosen
to go the less intrusive way for drbd-07.

Changing it over to alloc_bio() is something for drbd-08.

[...]
  ONLY_IN_26(unsigned int ee_size;)
  ONLY_IN_26(sector_t ee_sector;)
- // THINK: maybe we rather want bio_alloc(GFP_*,1)
+ // TODO: we rather want bio_alloc(GFP_*,1) all through the code!
  ONLY_IN_26(struct bio_vec ee_bvec;)

I am wondering if with a private copy of the bio_vec if we already
have a copy of the IO operations size and start sector that is 
still in place after the IO operation completed.

 -> If this is the case we could drop the ee_size and ee_sector members
    and take them form e.g. ee_bvec 

Jens, I guess you can answer that question  easily.

I will commit it to SVN...

-Philipp
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