Subject: Re: CVS commit: src/sys/dev
To: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
From: Christos Zoulas <christos@zoulas.com>
List: source-changes
Date: 03/05/2007 08:58:42
On Mar 5,  2:39pm, yamt@mwd.biglobe.ne.jp (YAMAMOTO Takashi) wrote:
-- Subject: Re: CVS commit: src/sys/dev

| > On Mar 5, 12:57pm, yamt@mwd.biglobe.ne.jp (YAMAMOTO Takashi) wrote:
| > -- Subject: Re: CVS commit: src/sys/dev
| > 
| > | > On Mar 5, 12:29pm, yamt@mwd.biglobe.ne.jp (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.

This is what Cliff Wright said, I did not.

christos