From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Dongjun Shin" <djshin90@gmail.com>
Subject: Re: Proposal to improve filesystem/block snapshot interaction
Date: Tue, 30 Oct 2007 19:49:09 +0900
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Cc: "Greg Banks" <gnb@sgi.com>,
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To: "Arnd Bergmann" <arnd@arndb.de>
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On 10/30/07, Arnd Bergmann <arnd@arndb.de> wrote:
> This make me curious, why would t13 want to invent a new command when
> there is already the erase command from CFA?
>
> It's not exactly the same, but close enough that the proposed BIO_HINT_RELEASE
> should probably be mapped to CFA_ERASE (0xc0) on drives that support it:
> http://t13.org/Documents/UploadedDocuments/technical/d97116r1.pdf
>

I'm not sure about the background.
However, it's definitely a sign that passing the deleted block info
to the flash-based storage is useful.

Anyway, BIO_HINT_RELEASE could destroy the content of the blocks
after being passed to the device. I think that other bio should not be
reordered
accross that hint (just like barrier).

Dongjun