Subject: Re: SCSI MMC device abstraction and UDF patch for review
To: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
From: Reinoud Zandijk <reinoud@netbsd.org>
List: tech-kern
Date: 12/27/2005 23:56:06
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On Tue, Dec 27, 2005 at 07:22:05AM +0900, YAMAMOTO Takashi wrote:
> > The two stubs for reading are to be integrated in a safeguard mechanism 
> > that orders read and write requests in such a way that it doesn't inflict 
> > adressing issues due to percularities in writing to recordables.
> 
> it also involves redundant memcpy, which can't be solved by B_NOCACHE.

i'd like to remove that redundant memcpy in time yes

> i'd say "safe" == "hide bugs".

hmmm... you got a point

> > > - is udf sector size ("lb_size" in udf_strategy)
> > >   always smaller than or equal to page size?
...
> 
> if it's larger than page size, page-aligned i/o can't be be represented
> in the unit.

I thought that was part of the point of genfs? to fix such things? by 
requesting overlapping sectors? In practice i dont think its a problem but 
i could add an check for lb_size to be a multiple of the page size or 
smaller than the page size to be on the safe side.

Cheers,
Reinoud


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