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Message-ID: <3E7A567E.3080409@zytor.com>
Date: Thu, 20 Mar 2003 16:02:06 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
Organization: Zytor Communications
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To: Joel Becker <Joel.Becker@oracle.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: Larger dev_t and major/minor split
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Joel Becker wrote:
> On Thu, Mar 20, 2003 at 03:06:31PM -0800, H. Peter Anvin wrote:
> 
>>Last I checked, all traditional (inode-based) Unix filesystems,
>>including ext2/3 used block pointers for dev_t.  There are plenty of
>>block pointers; 60 bytes worth.
> 
> 	They do indeed.  But ext2/3 touches that block pointer with
> cpu_to_le32() and friends.  It needs fixing at best, and compatability
> work for already existing partitions.
> 

A few options:

a) Use an inode flag indicating a large dev_t.  This is probably the
best option.

b) Use a sentinel value, e.g. 0xffffffff, to indicate that the major and
minor are in block pointers 1 and 2.

	-hpa


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