From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthew Wilcox <willy@linux.intel.com>
Subject: Re: NVM Mapping API
Date: Fri, 18 May 2012 13:19:01 -0400
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To: James Bottomley <James.Bottomley@HansenPartnership.com>
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On Fri, May 18, 2012 at 04:31:08PM +0100, James Bottomley wrote:
> On Fri, 2012-05-18 at 10:49 -0400, Matthew Wilcox wrote:
> > You're downplaying the complexity of your own solution while overstating
> > the complexity of mine.  Let's compare, using your suggestion of the
> > dmesg buffer.
> 
> I'll give you that one when you tell me how you use your vfs interface
> simply from within the kernel.  Both are always about the same
> complexity in user space ...
> 
> To be honest, I'm not hugely concerned whether the key management API is
> u32 or a string.  What bothers me the most is that there will be
> in-kernel users for whom trying to mmap a file through the vfs will be
> hugely more complex than a simple give me a pointer to this persistent
> region.

Huh?  You snipped the example where I showed exactly that.  The user
calls nvm_map() and gets back a pointer to a kernel mapping for the
persistent region.