DMA to User-Space

[Jonathan Haws]

> you can also reserve some physical memory at the top of memory and
> dma
> into that.
> of course, this means you have to know how much memory you need
> before
> booting the kernel.

I had thought about that, however can I mmap into memory that area if I have set mem=250M in the boot arguments?  I would plan to DMA to above 250M (up to 256M).  I know that would keep the kernel out of it, but will /dev/mem be able to "see" that memory if I had told the kernel it was not there?

Thanks for the help!

Jonathan