linux-kernel - Re: [PATCH 11/16] f2fs: add inode operations for special inodes

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]

Date:	Sun, 14 Oct 2012 16:09:05 +0900
From:	Jaegeuk Kim <jaegeuk.kim@...il.com>
To:	Vyacheslav Dubeyko <slava@...eyko.com>
Cc:	Arnd Bergmann <arnd@...db.de>,
	±èÀç±Ø <jaegeuk.kim@...sung.com>,
	viro@...iv.linux.org.uk, 'Theodore Ts'o' <tytso@....edu>,
	gregkh@...uxfoundation.org, linux-kernel@...r.kernel.org,
	chur.lee@...sung.com, cm224.lee@...sung.com,
	jooyoung.hwang@...sung.com
Subject: Re: [PATCH 11/16] f2fs: add inode operations for special inodes

2012-10-14 (ì¼), 02:21 +0400, Vyacheslav Dubeyko:
> On Oct 14, 2012, at 12:52 AM, Arnd Bergmann wrote:
> 
> > On Friday 05 October 2012, ê¹€ìž¬ê·¹ wrote:
> >> +const char *media_ext_lists[] = {
> >> +       "jpg",
> >> +       "gif",
> >> +       "png",
> >> +       "avi",
> >> +       "divx",
> >> +       "mp4",
> >> +       "mp3",
> >> ...
> > 
> >> + * Set multimedia files as cold files for hot/cold data separation
> >> + */
> >> +static inline void set_cold_file(struct inode *inode, const unsigned char *name)
> >> +{
> >> +       const char **extlist = media_ext_lists;
> >> +
> >> +       while (*extlist) {
> >> +               if (!is_multimedia_file(name, *extlist)) {
> >> +                       F2FS_I(inode)->is_cold = 1;
> >> +                       break;
> >> +               }
> >> +               extlist++;
> >> +       }
> >> +}
> > 
> > This is a very clever way of categorizing files by their name, but I wonder if hardcoding
> > the list of file name extensions at in the kernel source is the best strategy. Generally
> > I would consider this to be a policy that should be configurable by the user.
> > 
> > Unfortunately I can't think of a good interface to configure this, but maybe someone
> > else has a useful idea. Maybe the list can be stored in the superblock and get written
> > at mkfs time from the same defaults, but with the option of overriding it using
> > a debugfs tool.
> > 
> 
> By the way, how about extended attributes? It is possible to save in extended attribute a hint about file's content nature during creation operation or later. Moreover, extended attribute gives possibility to change hint after renaming operation, for example.
> 

I think xattr is not a proper way to communicate between file system and
users.
How about fadvise()?

> With the best regards,
> Vyacheslav Dubeyko.
> 
> > 	Arnd
> > --
> > 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/
> 
> --
> 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/

-- 
Jaegeuk Kim
Samsung

--
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/