From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dan Williams <dan.j.williams@intel.com>
Subject: Re: [Linux-nvdimm] [PATCH v2] pmem: Initial version of persistent
 memory driver
Date: Thu, 11 Sep 2014 09:31:14 -0700
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Cc: Boaz Harrosh <openosd@gmail.com>,
	Ross Zwisler <ross.zwisler@linux.intel.com>,
	Jens Axboe <axboe@kernel.dk>,
	Matthew Wilcox <matthew.r.wilcox@intel.com>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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To: Boaz Harrosh <boaz@plexistor.com>
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On Thu, Sep 11, 2014 at 3:45 AM, Boaz Harrosh <boaz@plexistor.com> wrote:
> On 09/11/2014 02:01 AM, Dan Williams wrote:
> <>
>>
>> Imagine you want to deploy a policy like "use half of the memory
>> provided by the dimm in slot3, i.e. the only one with a battery".
>> That sort of thing gets unwieldy in a command line string compared to
>> a description table format that we can update at will.
>>
>
> Actually it is easy to do, why? I do this here in the lab all the time.
> with a "command line" with this code you see here.
>
> [DDR3 NvDIMM which means I need memmap=16G\$32G on Kernel command line.
>  Then: modprobe pmem map=8G@32G,4G@44G,...
>  and so on Just as a simple example where 2/4-3/4 addresses are not used.
>  You can have holes in the middle or what ever you want. This here is just
>  a table in comma-separated format. If we need like flags in future we can
>  extend the format to nn@ss:flags, but I do no have any 3rd column yet]

The point I am getting at is not requiring a priori knowledge of the
physical memory map of a system.  Rather, place holder variables to
enable simple dynamic discovery.

> And again I have in the pipe a dynamic interface added on top of
> the module param one. So it will all be there soon. Without reverting
> the old one.

Why start on step 2 when we haven't got agreement on step 1?