Re: [PATCH 2/2] i_version update - ext4 part

[Mingming Cao <cmm@us.ibm.com>]

On Fri, 2007-10-05 at 17:28 +0200, Cordenner jean noel wrote:
> This patch update the i_version field of the inode and add a mount
> option to enable this feature. The other condition to enable this
> feature is that the inode size should be 256-bytes.
> 
> Signed-off-by: Jean Noel Cordenner <jean-noel.cordenner@bull.net>
> --- 
>  fs/ext4/inode.c         |    4 +++-
>  fs/ext4/super.c         |    7 ++++++-
>  include/linux/ext4_fs.h |    1 +
>  3 files changed, 10 insertions(+), 2 deletions(-)
> 
> Index: linux-2.6.23-rc8-ext4-i_version/fs/ext4/inode.c
> ===================================================================
> --- linux-2.6.23-rc8-ext4-i_version.orig/fs/ext4/inode.c	2007-10-03
> 18:11:17.000000000 +0200
> +++ linux-2.6.23-rc8-ext4-i_version/fs/ext4/inode.c	2007-10-05
> 10:26:42.000000000 +0200
> @@ -3173,7 +3173,9 @@
>  {
>  	int err = 0;
> 
> -	inode->i_version++;
> +	if (test_opt(inode->i_sb, I_VERSION))
> +		inode_inc_iversion(inode);
> +
>  	/* the do_update_inode consumes one bh->b_count */
>  	get_bh(iloc->bh);
> 
> Index: linux-2.6.23-rc8-ext4-i_version/fs/ext4/super.c
> ===================================================================
> --- linux-2.6.23-rc8-ext4-i_version.orig/fs/ext4/super.c	2007-10-03
> 18:11:17.000000000 +0200
> +++ linux-2.6.23-rc8-ext4-i_version/fs/ext4/super.c	2007-10-03
> 18:17:44.000000000 +0200
> @@ -742,7 +742,7 @@
>  	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
>  	Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
>  	Opt_grpquota, Opt_extents, Opt_noextents, Opt_delalloc,
> -	Opt_mballoc, Opt_nomballoc, Opt_stripe,
> +	Opt_mballoc, Opt_nomballoc, Opt_stripe, Opt_i_version,
>  };
> 
>  static match_table_t tokens = {
> @@ -800,6 +800,7 @@
>  	{Opt_mballoc, "mballoc"},
>  	{Opt_nomballoc, "nomballoc"},
>  	{Opt_stripe, "stripe=%u"},
> +	{Opt_i_version, "i_version"},
>  	{Opt_err, NULL},
>  	{Opt_resize, "resize"},
>  };
> @@ -1161,6 +1162,10 @@
>  				return 0;
>  			sbi->s_stripe = option;
>  			break;
> +		case Opt_i_version:
> +			set_opt (sbi->s_mount_opt, I_VERSION);
> +			sb->s_flags |= MS_I_VERSION;
> +			break;

Need to make sure this flag is cleared if remounted fs without I_VERSION

>  		default:
>  			printk (KERN_ERR
>  				"EXT4-fs: Unrecognized mount option \"%s\" "
> Index: linux-2.6.23-rc8-ext4-i_version/include/linux/ext4_fs.h
> ===================================================================
> --- linux-2.6.23-rc8-ext4-i_version.orig/include/linux/ext4_fs.h
> 2007-10-03 18:11:17.000000000 +0200
> +++ linux-2.6.23-rc8-ext4-i_version/include/linux/ext4_fs.h	2007-10-03
> 18:11:54.000000000 +0200
> @@ -500,6 +500,7 @@
>  #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT	0x1000000 /* Journal Async
> Commit */
>  #define EXT4_MOUNT_DELALLOC		0x2000000 /* Delalloc support */
>  #define EXT4_MOUNT_MBALLOC		0x4000000 /* Buddy allocation support */
> +#define EXT4_MOUNT_I_VERSION		0x8000000 /* i_version support */
>  /* Compatibility, for having both ext2_fs.h and ext4_fs.h included at
> once */
>  #ifndef _LINUX_EXT2_FS_H
>  #define clear_opt(o, opt)		o &= ~EXT4_MOUNT_##opt
> 


I don't see places where this counter is being stored/load to/from disk,
so I assume this is the not the full patch series?


Mingming