I am newbie too but to my understanding kernel memory is divided into following memory zones:
DMA_ZONE
NORMAL_ZONE
HIGHMEM_ZONE
and depending on arch of the machine these memory zone range gets defined. e.g. for x86 its 16MB
(24bit ISA address space) and on other platforms say ARM both DMA and NORMAL can be same. hence
kernel assigns its addressable address from 0 to 2^32 address into these different memory zones and
provides helper functions to request memory from these regions.
I am not sure if these ZONES can be changed as per requirement say making x86 DMA zone more than
16 MB. May be linux gurus on this alias could put more light on this.
Regards,
Vipul.
On Mon, Jul 27, 2009 at 6:21 AM, Deepak Vishwakarma <vishwakarma.deepak@xxxxxxxxx> wrote:
Hi guyz,
Need your favour!
How is DMA memory is allocated in kernel space? And how can it be increased?
Regards,
Deepak
