[vm 0/4] replace remap_page_range() with remap_pfn_range()

[William Lee Irwin III <wli@holomorphy.com>]

On Thu, Sep 23, 2004 at 06:22:22PM -0500, John Fusco wrote:
> I have a problem and I would like some comments on how to fix it.
> I have a custom PCI-X device installed in an IA32 system.  The device 
> expects to see a flat contiguous address space on the host, from which 
> it reads and sends its data.  The technique I used is right out of the 
> O'Reilly Device Drivers book, which is to hide memory from the kernel 
> with the 'mem=YYY' boot parameter.  I then provide a mmap method to map 
> the contiguous (hidden) memory into user space via a call to 
> 'remap_page_range'.
> Everything worked great until we decided that we needed to install 6GB 
> in this system.  The problem is that remap_page_range() uses an unsigned 
> long as the parameter for a physical address.  On IA32, an unsigned long 
> is 32-bits, but the IA32 is capable of addressing well over 4GB of RAM.  
> So physical addresses on IA32 must be larger than 32 bits.

Do these patches work for you? Compiletested on sparc64.


-- wli