Re: CVS commit: src/sys/dev

[yamt%mwd.biglobe.ne.jp@localhost (YAMAMOTO Takashi)]

> On Mar 5, 12:57pm, yamt%mwd.biglobe.ne.jp@localhost (YAMAMOTO Takashi) wrote:
> -- Subject: Re: CVS commit: src/sys/dev
> 
> | > On Mar 5, 12:29pm, yamt%mwd.biglobe.ne.jp@localhost (YAMAMOTO Takashi) 
> wrote:
> | > -- Subject: Re: CVS commit: src/sys/dev
> | > 
> | > | > Module Name:  src
> | > | > Committed By: christos
> | > | > Date:         Mon Mar  5 02:55:32 UTC 2007
> | > | > 
> | > | > Modified Files:
> | > | >       src/sys/dev: vnd.c
> | > | > 
> | > | > Log Message:
> | > | > Fix compression problem from Cliff Wright:
> | > | >   Break one: because b_cylinder, and b_resid are one and the same.
> | > | > The work the routine was commented as being its primary function,
> | > | > end of patition adjustment, is wiped out, as at the end of
> | > | > the routine b_cylinder is set, splat, doing a wipe out of the 
> adjustment
> | > | > to b_resid.
> | > | >   Break two: When doing the adjustment, a block count is created from 
> a
> | > | > byte count, a block calculation is done, then the results are 
> compared to
> | > | > the original byte count. i.e. apples to oranges, not blocks to blocks,
> | > | > but blocks to bytes.
> | > | >   Break three: since if all the other drivers that used this routine
> | > | > would have broken as vnd compress did, I must assume they always 
> ignored
> | > | > the results of this routine. So if end of patition adjustment is
> | > | > really required then all these other drivers have been broken for a
> | > | > long time.
> | > | 
> | > | which "routine" are you talking about?
> | > 
> | > bounds_check_with_label()?
> | > 
> | > christos
> | 
> | are you going to fix it?
> 
> I have not decided what the best fix is. Do you have time to look at it?
> 
> christos

i don't even understand what problems you are talking about.
b_cylinder calculation in bounds_check_with_label?

btw, i think the right fix for vnd.c is to make compstrategy not to
use b_resid as an input.

YAMAMOTO Takashi