Subject: Re: isa_dmastart return value ignored?
To: Leo Weppelman <>
From: Jason R Thorpe <>
List: tech-kern
Date: 02/22/2001 08:45:34
On Thu, Feb 22, 2001 at 09:15:11AM +0100, Leo Weppelman wrote:

 > A quick grep through dev/isa showed that none of the drivers using
 > isa_dmastart() is actually checking the results. This makes me wonder if
 > I am doing something wrong...

When the DMA map is created, you need to make sure to allocate a bounce
buffer for data that could end up being fragmented across multiple pages.

See the various isadma_machdep.c files or the i386 isa_machdep.c.

        -- Jason R. Thorpe <>