linux-ext4 - Re: [PATCH V3 0/8] Cleancache: overview

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <4C49ADA3.9060501@vflare.org>
Date:	Fri, 23 Jul 2010 20:26:35 +0530
From:	Nitin Gupta <ngupta@...are.org>
To:	Minchan Kim <minchan.kim@...il.com>
CC:	Dan Magenheimer <dan.magenheimer@...cle.com>,
	chris.mason@...cle.com, viro@...iv.linux.org.uk,
	akpm@...ux-foundation.org, adilger@....com, tytso@....edu,
	mfasheh@...e.com, joel.becker@...cle.com, matthew@....cx,
	linux-btrfs@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-fsdevel@...r.kernel.org, linux-ext4@...r.kernel.org,
	ocfs2-devel@....oracle.com, linux-mm@...ck.org, jeremy@...p.org,
	JBeulich@...ell.com, kurt.hackel@...cle.com, npiggin@...e.de,
	dave.mccracken@...cle.com, riel@...hat.com, avi@...hat.com,
	konrad.wilk@...cle.com
Subject: Re: [PATCH V3 0/8] Cleancache: overview

On 07/23/2010 01:46 PM, Minchan Kim wrote:
> On Fri, Jul 23, 2010 at 4:36 PM, Nitin Gupta <ngupta@...are.org> wrote:
>>
>> 2. I think change in btrfs can be avoided by moving cleancache_get_page()
>> from do_mpage_reapage() to filemap_fault() and this should work for all
>> filesystems. See:
>>
>> handle_pte_fault() -> do_(non)linear_fault() -> __do_fault()
>>                                                -> vma->vm_ops->fault()
>>
>> which is defined as filemap_fault() for all filesystems. If some future
>> filesystem uses its own custom function (why?) then it will have to arrange for
>> call to cleancache_get_page(), if it wants this feature.
> 
> 
> filemap fault works only in case of file-backed page which is mapped
> but don't work not-mapped cache page.  So we could miss cache page by
> read system call if we move it into filemap_fault.
> 
> 

Oh, yes. Then we need cleancache_get_page() call in do_generic_file_read() too.
So, if I am missing anything now, we should now be able to get rid of per-fs
changes.

Thanks,
Nitin
--
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