Subject: Re: Valid use of bus_dma(9)?
To: john heasley <>
From: Jochen Kunz <>
List: tech-kern
Date: 07/22/2004 15:56:53
On Thu, 22 Jul 2004 06:50:09 -0700
john heasley <> wrote:

> > Thus resulting in a double mapping of the previously allocated and maped
> > "x" DMA memory. The physical "y" memory is subregion of the physical "x"
> > memory mapped at a different KVA.
> I believe thats the purpose of
> bus_space(9):
>      Some drivers need to be able to pass a subregion of already-mapped b=
>      space to another driver or module within a driver.  The
>      bus_space_subregion() function allows such subregions to be created.
I am talking about bus_dma(9), not bus_space(9)...