From mboxrd@z Thu Jan  1 00:00:00 1970
From: Carsten Otte <cotte@de.ibm.com>
Subject: Re: [patch 4/6] xip: support non-struct page backed memory
Date: Mon, 03 Mar 2008 09:30:29 +0100
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Cc: Jared Hulbert <jaredeh@gmail.com>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	mschwid2@linux.vnet.ibm.com, heicars2@linux.vnet.ibm.com,
	linux-mm@kvack.org, linux-fsdevel@vger.kernel.org
To: Nick Piggin <npiggin@suse.de>
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Nick Piggin wrote:
> What about 
> int get_xip_mem(mapping, pgoff, create, void **kaddr, unsigned long *pfn)
> 
> get_xip_mem(mapping, pgoff, create, &addr, &pfn);
> if (pagefault)
>     vm_insert_mixed(vma, vaddr, pfn);
> else if (read/write) {
>     memcpy(kaddr, blah, sizeof);
> 
> My simple brd driver can easily do
>  *kaddr = page_address(page);
>  *pfn = page_to_pfn(page);
> 
> This should work for you too?
Looks good to me. Otoh, if there is an easy way to fix virt_to_phys() 
I would like that better.