lkml.org 
[lkml]   [2009]   [Oct]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 15/41] whiteout: ext2 whiteout support
On 2009-10-21, at 13:19, Valerie Aurora wrote:
> This patch adds whiteout support to EXT2. A whiteout is an empty
> directory
> entry (inode == 0) with the file type set to EXT2_FT_WHT. Therefore it
> allocates space in directories. Due to being implemented as a
> filetype it is
> necessary to have the EXT2_FEATURE_INCOMPAT_FILETYPE flag set.
>
> diff --git a/include/linux/ext2_fs.h b/include/linux/ext2_fs.h
> index 121720d..bd10826 100644
> --- a/include/linux/ext2_fs.h
> +++ b/include/linux/ext2_fs.h
> @@ -189,6 +189,7 @@ struct ext2_group_desc
> +#define EXT2_OPAQUE_FL 0x00040000

Please check in the upstream e2fsprogs ext2_fs.h before defining new
flag
values for ext2/3/4. In this case, 0x40000 conflicts with
EXT4_HUGE_FILE_FL,
which is of course bad.

> @@ -503,10 +504,12 @@ struct ext2_super_block {
> #define EXT2_FEATURE_INCOMPAT_META_BG 0x0010
> +#define EXT2_FEATURE_INCOMPAT_WHITEOUT 0x0020

This one doesn't conflict, probably due to luck, because 0x0040-0x0200
are
already in use for other features. I'm not sure if 0x0020 was
reserved for
some other use, or just skipped to avoid potential conflicts.


Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.



\
 
 \ /
  Last update: 2009-10-21 23:21    [from the cache]
©2003-2011 Jasper Spaans