[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <m3sld636g0.fsf@bzzz.home.net>
Date: Fri, 16 Feb 2007 10:30:39 +0300
From: Alex Tomas <alex@...sterfs.com>
To: Andrew Morton <akpm@...ux-foundation.org>
Cc: Alex Tomas <alex@...sterfs.com>, Eric Sandeen <sandeen@...hat.com>,
"Theodore Ts'o" <tytso@....edu>,
"linux-ext4@...r.kernel.org" <linux-ext4@...r.kernel.org>
Subject: Re: booked-page-flag.patch
>>>>> Andrew Morton (AM) writes:
-> get_block(with BH_Delay) can be used to signal
>> filesystem that no actual allocation is required.
>> so, aware filesystem can just reserve space. then
-> writepages() should walk through the pages like
>> it does currently, collect contiugous sequences
>> and again call ->get_block(w/o BH_Delay) with b_size
>> covering all contiguous pages ...
>>
AM> That sounds like it'd work, yes.
AM> Except for an address_space which is using delayed allocation, its
-> prepare_write wouldn't call get_block at all, so perhaps that isn't
AM> needed.
hmm. I thought it has to call get_block() at least to know whether
the block is already allocated. and I was going to reserve space
in prepare_write for which some fs-specific method is needed becase
only fs knows how much metadata it'd need.
thanks, Alex
-
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists