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Subject:	Re: Beta Test: CWSDPMI r7 - 4GB support
From:	jimmyliaoo AT gmail DOT com
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> Let's suppose your computer has 4GB physical memory.  Typically between 
> 2.5GB and 3.5GB of that memory is actually below the 4GB address point.  The 
> remaining typically starts at the 4GB address point.  On this computer you 
> could just sbrk() up to 4092K,
> then touch the memory in order (first byte in each 4MB aligned page).  

I think what you want to express is: the remaining memory will be "re-mapped" to above 4GB address via sbrk(). Am I correct ?
 
> If you then look at the physical map, you will very likely
> have at least a 500MB buffer you can configure that actually is above the 
> 4GB address.

Here "at least a 500MB buffer you can configure" means: application(or program) can access this buffer using "indirect" way, am I correct ?
(where indirect way means you have to invoke api(or system call) to get pointer first, then access it...)

If above is correct, then can I get the "physical memory address" of that buffer ?
(the reason I ask is: H/W DMA transfer requires only the physical memory address !)

* To sum up, s/w access that buffer(above 4GB physically) indirectly but h/w access it directly(no transform, no remap)

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