linux-kernel - Re: [PATCH RESEND] udf: extent cache implementation for manipulating block map

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <20120822100826.GB20640@quack.suse.cz>
Date:	Wed, 22 Aug 2012 12:08:26 +0200
From:	Jan Kara <jack@...e.cz>
To:	Namjae Jeon <linkinjeon@...il.com>
Cc:	Jan Kara <jack@...e.cz>, akpm@...ux-foundation.org,
	linux-kernel@...r.kernel.org,
	Namjae Jeon <namjae.jeon@...sung.com>,
	Ashish Sangwan <a.sangwan@...sung.com>,
	Bonggil Bak <bgbak@...sung.com>
Subject: Re: [PATCH RESEND] udf: extent cache implementation for
 manipulating block map

On Wed 22-08-12 19:02:26, Namjae Jeon wrote:
> 2012/8/21, Jan Kara <jack@...e.cz>:
> Hi. Jan.
> Okay, We are trying to do it from your comment.
> 1. Change udf_ext_cache structure to following which would also include *bh.
> struct udf_ext_cache {
> 
> /* Position of the cached extent */
> struct extent_position epos;
> 
> /* Logical block where cached extent starts */
> sector_t block;
> };
  OK.

> 2. Remove call to brelse(epos.bh) from all the callers of inode_bmap()
> and move it to udf_evict_inode()
  It might be easier to keep brelse() where it is and add get_bh() to
udf_add_extent_cache() and brelse() to udf_clear_extent_cache(). It is then
easier to audit we don't leak bh references...

> 3. As now we are not caching elen, etype and eloc, we have to change
> the cache_hit logic in inode_bmap.
> The call to function udf_next_aext is now necessary from inode_bmap.
  Yes.

> 4. Remove call to udf_clear_extent_cache() from udf_get_block as with
> new scheme, it is not required.
  You still need this when you write before the cached location (e.g. when
the file has holes, and you write into them, extents will shift).


								Honza
-- 
Jan Kara <jack@...e.cz>
SUSE Labs, CR
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/