On Apr 12, 2017, at 1:26 AM, Jan Kara <jack@suse.cz> wrote:
> 
> Currently we set IMMUTABLE and NOATIME flags on quota files to stop
> userspace from messing with them. Now that all filesystems set these
> flags in their quota_on handlers, we can stop setting the flags in
> generic quota code. This will allow filesystems to stop copying i_flags
> to their on-disk flags on various occasions.
> 
> Signed-off-by: Jan Kara <jack@suse.cz>

Reviewed-by: Andreas Dilger <adilger@dilger.ca>

> ---
> fs/quota/dquot.c | 19 +++++--------------
> 1 file changed, 5 insertions(+), 14 deletions(-)
> 
> diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
> index 74b489e3714d..7e94cb0ecdde 100644
> --- a/fs/quota/dquot.c
> +++ b/fs/quota/dquot.c
> @@ -2188,8 +2188,7 @@ int dquot_disable(struct super_block *sb, int type, unsigned int flags)
> 		/* This can happen when suspending quotas on remount-ro... */
> 		if (toputinode[cnt] && !sb_has_quota_loaded(sb, cnt)) {
> 			inode_lock(toputinode[cnt]);
> -			toputinode[cnt]->i_flags &= ~(S_IMMUTABLE |
> -				  S_NOATIME | S_NOQUOTA);
> +			toputinode[cnt]->i_flags &= ~S_NOQUOTA;
> 			truncate_inode_pages(&toputinode[cnt]->i_data, 0);
> 			inode_unlock(toputinode[cnt]);
> 			mark_inode_dirty_sync(toputinode[cnt]);
> @@ -2237,7 +2236,6 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
> 	struct super_block *sb = inode->i_sb;
> 	struct quota_info *dqopt = sb_dqopt(sb);
> 	int error;
> -	int oldflags = -1;
> 
> 	if (!fmt)
> 		return -ESRCH;
> @@ -2285,9 +2283,7 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
> 		 * possible) Also nobody should write to the file - we use
> 		 * special IO operations which ignore the immutable bit. */
> 		inode_lock(inode);
> -		oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE |
> -					     S_NOQUOTA);
> -		inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE;
> +		inode->i_flags |= S_NOQUOTA;
> 		inode_unlock(inode);
> 		/*
> 		 * When S_NOQUOTA is set, remove dquot references as no more
> @@ -2329,14 +2325,9 @@ static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
> 	dqopt->files[type] = NULL;
> 	iput(inode);
> out_file_flags:
> -	if (oldflags != -1) {
> -		inode_lock(inode);
> -		/* Set the flags back (in the case of accidental quotaon()
> -		 * on a wrong file we don't want to mess up the flags) */
> -		inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE);
> -		inode->i_flags |= oldflags;
> -		inode_unlock(inode);
> -	}
> +	inode_lock(inode);
> +	inode->i_flags &= ~S_NOQUOTA;
> +	inode_unlock(inode);
> out_fmt:
> 	put_quota_format(fmt);
> 
> --
> 2.12.0
> 


Cheers, Andreas