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Message-ID: <b6c5339f0510180812p3ff6d0b1ia204b28c4e50186d@mail.gmail.com>
Date: Tue, 18 Oct 2005 11:12:12 -0400
From: Bob Copeland <email@bobcopeland.com>
To: Anton Altaparmakov <aia21@cam.ac.uk>
Subject: Re: file system block size
Cc: Roushan Ali <roushan.ali@gmail.com>, Nathan Scott <nathans@sgi.com>,
       linux-kernel@vger.kernel.org
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> Indeed, it makes everything harder.  Have a look at ntfs in the kernel
> which has to cope with file system block sizes between 512 bytes and
> several hundred kiB (at least they are in powers of two thank
> goodness...).  You end up not being able to use a lot of generic
> functions as you for example need to lock multiple pages which needs to
> be ordered correctly, etc...  If you look at the latest -mm kernel, the
> ntfs driver there has file write(2) support for any cluster size and you
> will see an example of the multiple page locking problem solution there.

Any chance this will make it into common code?  I also need it for my
filesystem driver (here: http://bobcopeland.com/karma/).  So far I've
only done read side which is not too bad, but as you say writing makes
things complicated.

That, and the extent-supporting mpage_readpages would make me a happy person.

-Bob
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