linux-ext4 - [PATCH 05/11] quota: Stop setting IMMUTABLE and NOATIME flags on quota files

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Date:   Wed, 12 Apr 2017 09:26:05 +0200
From:   Jan Kara <jack@...e.cz>
To:     <linux-fsdevel@...r.kernel.org>
Cc:     <linux-ext4@...r.kernel.org>, <reiserfs-devel@...r.kernel.org>,
        jfs-discussion@...ts.sourceforge.net, Jan Kara <jack@...e.cz>
Subject: [PATCH 05/11] quota: Stop setting IMMUTABLE and NOATIME flags on quota files

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@...e.cz>
---
 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