Thank you ! I will try kmap/kunmap later. On Fri, Nov 11, 2011 at 4:20 PM, Dave Hylands <dhylands@gmail.com> wrote:
Hi Geraint,
On Thu, Nov 10, 2011 at 8:44 PM, Geraint Yang <geraint0923@gmail.com> wrote:
Hi Dave, Thank you for your help ! Does it mean that I could use all of the memory my computer has? But one of my classmates told me that kernel could only use 1G from a 4G memory.computer...Is there anything I have misunderstood ?
There is a certain amount (exact amount depends on the architecture and configuration) that can be accessed directly all of the time.
Then there is high memory, which can be accessed using kmap/kunmap. See http://linux-mm.org/HighMemory
If you have a 64-bit system, then you can access all of the memory directly.
-- Dave Hylands Shuswap, BC, Canada http://www.davehylands.com
-- Geraint Yang Tsinghua University Department of Computer Science and Technology