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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Alexey Tarasov <me@lexasoft.ru>
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Date: Thu, 08 Apr 2010 16:24:12 +0200
In-Reply-To: <F2541C05-A42C-486F-9709-56315C2F49FF@lexasoft.ru> (Alexey
	Tarasov's message of "Thu, 8 Apr 2010 18:12:22 +0400")
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Cc: freebsd-current@freebsd.org
Subject: Re: gpart and sector size
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Alexey Tarasov <me@lexasoft.ru> writes:
> Ok, in case of GPT? :-)

I doubt it, but I don't know for sure.

> GPT implementation can be the simplest solution to this problem
> compared to implementing additional ATA commands to determine if disk
> is in Advanced Format.

There are two issues:

1) There is already an ATA command to report both physical and logical
   sector sizes, but the disk lies - it always reports 512/512.

2) The disk may have already been formatted on a system that doesn't
   support 4k sectors, and may contain unaligned partitions and file
   systems, which won't be visible if we forcibly and unconditionally
   use 4k sectors.

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no