From mboxrd@z Thu Jan  1 00:00:00 1970
From: Edward Shishkin <edward.shishkin@gmail.com>
Subject: Re: [veryRFC] [PATCH 0/2] reiser4: discard before dealloc: first
 approximation.
Date: Thu, 17 Jul 2014 13:14:06 +0200
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To: Ivan Shapovalov <intelfx100@gmail.com>
Cc: reiserfs-devel@vger.kernel.org

On 07/17/2014 11:46 AM, Ivan Shapovalov wrote:
> On Thursday 17 July 2014 at 01:35:20, Edward Shishkin wrote:	
>> On 07/16/2014 01:24 PM, Ivan Shapovalov wrote:
>>> This needs your version of discard algorithm, because blocks inside extents of
>>> discard set are now marked as allocated.
>>
>> OK, I'll try to finish it in weekends..
>>
>>
>>> BTW, have you dropped the case with erase unit size < block size?
>>
>> In my version all erase units are supported except ones which are
>> not a power of 2. We can support all erase units without exceptions,
>> if needed.
> I mean, when erase unit size < block size, erase unit size is forced to be
> exactly one block. Again, this is OK, but in this case any alignment (by
> definition less than one block then) will be dropped and represented as zero,
> and _this_ deserves a warning :)


The case of alignment % block_size != 0 deserves to disable discard
support, because in this case all this science with heads and tails
simply doesn't work.


>
> // btw, as you probably guess, these two patches are completely untested.
>
> Thanks,