Path: utzoo!attcan!uunet!seismo!sundc!pitstop!sun!amdcad!ames!mailrus!bcm!uhnix2!uhnix1!sugar!peter
From: peter@sugar.UUCP (Peter da Silva)
Newsgroups: comp.sys.amiga
Subject: Re: A plea for bad block handling in the file system.
Message-ID: <2026@sugar.UUCP>
Date: 20 May 88 00:15:48 GMT
References: <2009@sugar.UUCP> <7144@swan.ulowell.edu>
Organization: Sugar Land UNIX - Houston, TX
Lines: 45

In article <7144@swan.ulowell.edu>, page@ulowell.UUCP writes:
> peter@sugar.UUCP (Peter da Silva) wrote:
> >I'd just like to make another plea for bad block handling in the filesystem.

> And I'll point out again that it's none of the FS' business what the
> physical device looks like.  Let the driver present a perfect pack to
> the file system.

Since the drivers (demonstrably) don't do this, this is really not
a very good argument.


> >That's where it belongs: not duplicated dozens of times in dozens of drivers.

> Sure, duplicated code in dozens of filesystems.

There are today, and will be as far as I can forsee, a lot more drivers than
filesystems. Also, you (or Commodore, rather) have control over the filesystem.
The drivers are written by dozens of people.

> Not today, but eventually.

I can't see what you could possibly mean by this.

> Protocols in dealing with bad blocks between file systems
> and drivers will expand, and soon everyone on USENET will be
> discussing how to 'standardize' the protocols for filesystems talking
> to drivers, and how bad blocks should be handled.

There's already a protocol by which a driver can tell a filesystem
it's got a bad block. It's called an error.

> >but it's also better because the filesystem has more information
> >about what that bad block *means*... FS should be able to move the
> >block elsewhere.

> So should the driver.  And the beauty is it doesn't care what the data is.

So now you have another layer of complexity between the file and the
hardware. Something else to go wrong. The filesystem already has pointers
to the block. Why not use them?
-- 
-- Peter da Silva      `-_-'      ...!hoptoad!academ!uhnix1!sugar!peter
-- "Have you hugged your U wolf today?" ...!bellcore!tness1!sugar!peter
-- Disclaimer: These may be the official opinions of Hackercorp.