Re: DMA memory limitation?

[Vasu Varma P V]

but we have a macro in include/asm-i386/dma.h,
MAX_DMA_ADDRESS  (PAGE_OFFSET+0x1000000).

if i change it to a higher value, i am able to get more dma
memory. Is there any way i can change this without compiling
the kernel?

Arjan van de Ven wrote:

> Vasu Varma P V wrote:
> >
> > Hi,
> >
> > Is there any limitation on DMA memory we can allocate using
> > kmalloc(size, GFP_DMA)? I am not able to acquire more than
> > 14MB of the mem using this on my PCI SMP box with 256MB ram.
> > I think there is restriction on ISA boards of 16MB.
> > Can we increase it ?
>
> Why?
> YOu don't have to allocate GFP_DMA memory for PCI cards!
> GFP_DMA is for ISA cards only