Re: [patch] block highmem zero bounce v14

Jens Axboe
2001-09-16T22:00:16Z

On Sun, Sep 16 2001, Linus Torvalds wrote:
>
> On Sun, 16 Sep 2001, Jens Axboe wrote:
> >
> > It's against 2.4.10-pre9 and can be found right here:
> >
> > *.kernel.org/pub/linux/kernel/people/axboe/patches/2.4.10-pre9/block-highmem-all-14
>
> Jens, what's your feeling about the stability of these things, especially
> wrt weird drivers?

One of the very first decisions I made wrt this patch was to make sure
that weird/old drivers could keep on working exactly the way they do now
and never have to worry about highmem stuff. That basically means
enabling the stuff on a per-driver basis after it's considered safe. The
can_dma_32 for SCSI and highmem for IDE flag serves that purpose. Stand
alone block drivers just use blk_queue_bounce_limit to enable highmem
I/O after blk_init_queue, if they don't they get highmem pages bounced
as they are used too.

That leaves drivers that are 'different', stuff like ide-scsi for
instance. I think I have most of these under control...

> Ie do you think this is really a 2.4.x thing, or early 2.5.x?

Most of it is really a cautious back port of the 2.5 stuff I've been
working on, and with the above considerations it is/was meant as a 2.4
thing :-)

--
Jens Axboe