Re: [PATCH v2] f2fs: fix to set noatime and immutable flag for quota file

Jaegeuk Kim
2023-05-26T17:05:10Z

On 05/25, Chao Yu wrote:
> We should set noatime bit for quota files, since no one cares about
> atime of quota file, and we should set immutalbe bit as well, due to
> nobody should write to the file through exported interfaces.
>
> Meanwhile this patch use inode_lock to avoid race condition during
> inode->i_flags, f2fs_inode->i_flags update.
>
> Signed-off-by: Chao Yu <chao@kernel.org>
> ---
> v2:
> - fix to detect i_flags status correctly.
> fs/f2fs/super.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> index 51812f459581..1cf84c993d7c 100644
> --- a/fs/f2fs/super.c
> +++ b/fs/f2fs/super.c
> @@ -2763,7 +2763,17 @@ static int f2fs_quota_enable(struct super_block *sb, int type, int format_id,
> }
>
> /* Don't account quota for quota files to avoid recursion */
> + inode_lock(qf_inode);
> qf_inode->i_flags |= S_NOQUOTA;
> +
> + if (!(F2FS_I(qf_inode)->i_flags & F2FS_NOATIME_FL) ||
> + !(F2FS_I(qf_inode)->i_flags & F2FS_IMMUTABLE_FL)) {

What about this?

if ((F2FS_I(qf_inode)->i_flags & qf_flag) != qf_flag)

> + F2FS_I(qf_inode)->i_flags |=
> + F2FS_NOATIME_FL | F2FS_IMMUTABLE_FL;
> + f2fs_set_inode_flags(qf_inode);
> + }
> + inode_unlock(qf_inode);
> +
> err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
> iput(qf_inode);
> return err;
> --
> 2.40.1