Re: MO-Drive under 2.4.3

Jens Axboe (axboe@suse.de)
Sun, 22 Apr 2001 04:36:18 +0200


On Sun, Apr 22 2001, Alan Cox wrote:
> > a) Put in lots of bigblock special case code in FAT;
> > b) teach submit_bh() or generic_make_request() to transparently reblock
> > bhs < hw_blksize and remove most special cases from FAT. Specifically,
> > it ought to stop pretending in sb->s_blocksize to use 2k blocks when
> > the fs is really tied to 512 byte blocks.
> >
> > I tend to favour b), but which one is more likely to be accepted?
>
> Al Viro suggested c) which was to transparently make it a loopback mount of
> the raw device and let a loopback layer do the work.

... which is basically the same thing, in that we need to support writes
< hardware block size to devices. This is never going to be an efficient
mechanism, the read gathering required for a 512b write on a 2048b media
is scary. Think cd-rw 64kB blocksize for write. Ugh.

-- 
Jens Axboe

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