ext4: on a remount, only log the ro or r/w state when it has changed

[ Upstream commit d7b0befd09320e3356a75cb96541c030515e7f5f ]

A user complained that a message such as:

EXT4-fs (nvme0n1p3): re-mounted UUID ro. Quota mode: none.

implied that the file system was previously mounted read/write and was
now remounted read-only, when it could have been some other mount
state that had changed by the "mount -o remount" operation.  Fix this
by only logging "ro"or "r/w" when it has changed.

https://bugzilla.kernel.org/show_bug.cgi?id=219132

Signed-off-by: Nicolas Bretz <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
(cherry picked from commit 37ac2434aae16b4a36fec163edc2928a7acf599c)
Signed-off-by: Jack Vogel <[email protected]>

Author: nicbretz

fs/ext4/super.c

@@ -6744,6 +6744,7 @@ static int ext4_reconfigure(struct fs_context *fc)
 {
 	struct super_block *sb = fc->root->d_sb;
 	int ret;
+	bool old_ro = sb_rdonly(sb);
 
 	fc->s_fs_info = EXT4_SB(sb);
 
@@ -6755,9 +6756,9 @@ static int ext4_reconfigure(struct fs_context *fc)
 	if (ret < 0)
 		return ret;
 
-	ext4_msg(sb, KERN_INFO, "re-mounted %pU %s. Quota mode: %s.",
-		 &sb->s_uuid, sb_rdonly(sb) ? "ro" : "r/w",
-		 ext4_quota_mode(sb));
+	ext4_msg(sb, KERN_INFO, "re-mounted %pU%s.",
+		 &sb->s_uuid,
+		 (old_ro != sb_rdonly(sb)) ? (sb_rdonly(sb) ? " ro" : " r/w") : "");
 
 	return 0;
 }