Re: [PATCH 1/5 v2] blk-mq: Add prep/unprep support

From: Matias Bjorling <m@bjorling.me>
To: Christoph Hellwig <hch@infradead.org>
Cc: keith.busch@intel.com, javier@paletta.io,
	linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
	axboe@fb.com, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 1/5 v2] blk-mq: Add prep/unprep support
Date: Sun, 19 Apr 2015 20:12:58 +0200	[thread overview]
Message-ID: <5533F02A.6020208@bjorling.me> (raw)
In-Reply-To: <20150418201610.GB20311@infradead.org>

> On Sat, Apr 18, 2015 at 08:45:19AM +0200, Matias Bjorling wrote:
<snip>
>> The reason it shouldn't be under the a single block device, is that a target
>> should be able to provide a global address space.
>> That allows the address
>> space to grow/shrink dynamically with the disks. Allowing a continuously
>> growing address space, where disks can be added/removed as requirements grow
>> or flash ages. Not on a sector level, but on a flash block level.
>
> I don't understand what you mean with a single block device here, but I
> suspect we're talking past each other somehow.

Sorry. I meant that several block devices should form a single address 
space (exposed as a single block device), consisting of all the flash 
blocks. Applications could then get/put from that.

Thanks for your feedback. I'll push the pieces around and make the 
integration self-contained outside of the block layer.